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Cost-effectiveness of a mentorship and quality improvement intervention to enhance the quality of antenatal care at rural health centers in Rwanda.
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To estimate cost-effectiveness of Mentorship, Enhanced Supervision for Healthcare and Quality Improvement (MESH-QI) intervention to strengthen the quality of antenatal care at rural health centers in rural Rwanda.
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The State of Meghalaya, India, has some of the worst newborn health outcomes in the country. State health authorities commissioned an assessment of newborn service delivery to improve services. This study proposes bottleneck analysis (BNA) and quality improvement (QI) methods as a combined method to improve compliance with evidence-based neonatal interventions in newborn health facilities.
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Cost-effectiveness of a mentorship and quality improvement intervention to enhance the quality of antenatal care at rural health centers in Rwanda.
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To estimate cost-effectiveness of Mentorship, Enhanced Supervision for Healthcare and Quality Improvement (MESH-QI) intervention to strengthen the quality of antenatal care at rural health centers in rural Rwanda.
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This study aimed to evaluate the effect of introduction and subsequent withdrawal of the Results-based Financing for Maternal and Newborn Health Initiative (RBF4MNH) in Malawi on utilisation of facility-based childbirths, antenatal care (ANC) and postnatal care (PNC).
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Cost-effectiveness of a mentorship and quality improvement intervention to enhance the quality of antenatal care at rural health centers in Rwanda.
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To estimate cost-effectiveness of Mentorship, Enhanced Supervision for Healthcare and Quality Improvement (MESH-QI) intervention to strengthen the quality of antenatal care at rural health centers in rural Rwanda.
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The Tabora Maternal and Newborn Health Initiative project was a multicomponent intervention to improve maternal and newborn health in the Tabora region of Tanzania. Components included training healthcare providers and community health workers, infrastructure upgrades, and improvements to health management. This study aimed to examine the impact of trainings on four key outcomes: skilled birth attendance, antenatal care, respectful maternity care and patient-provider communication.
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Cost-effectiveness of a mentorship and quality improvement intervention to enhance the quality of antenatal care at rural health centers in Rwanda.
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To estimate cost-effectiveness of Mentorship, Enhanced Supervision for Healthcare and Quality Improvement (MESH-QI) intervention to strengthen the quality of antenatal care at rural health centers in rural Rwanda.
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Monetary incentives are often used to increase the motivation and output of health service providers. However, the focus has generally been on frontline health service providers. Using a cluster randomized trial, we evaluate the effect of monetary incentives provided to community-based volunteers on early initiation of antenatal care (ANC) visits and deliveries in health facilities in communities in Zambia. Monetary incentives were assigned to community-based volunteers in treatment sites, and payments were made for every woman referred or accompanied in the first trimester of pregnancy during January-June 2020. We find a significant increase of about 32 percent in the number of women completing ANC visits in the first trimester but no effect on service coverage rates. The number of women accompanied by community-based volunteers for ANC in the first trimester increased by 33 percent. The number of deliveries in health facilities also increased by 22 percent. These findings suggest that the use of health facilities during the first trimester of pregnancy can be improved by providing community-based volunteers with monetary incentives and that such incentives can also increase deliveries in health facilities, which are key to improving the survival of women and newborns.
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Cost-effectiveness of a mentorship and quality improvement intervention to enhance the quality of antenatal care at rural health centers in Rwanda.
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To estimate cost-effectiveness of Mentorship, Enhanced Supervision for Healthcare and Quality Improvement (MESH-QI) intervention to strengthen the quality of antenatal care at rural health centers in rural Rwanda.
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Antenatal care utilization is one of the means for reducing the high maternal mortality rates in sub-Saharan Africa. This study examined the association between barriers to healthcare access and implementation of the 2016 WHO antenatal care services model among pregnant women seeking antenatal care in selected countries in sub-Saharan Africa.
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HPLC-Mass spectrometry analysis of phenolics comparing traditional bilberry and blueberry liqueurs.
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The purpose of this study was to investigate the differences between the phenolics compositions of bilberry and blueberry liqueurs, to determine whether these are comparable. Both bilberry and blueberry liqueurs have the same name on the market, however they differ in phenolic composition and content. A total of 43 compounds were identified, 36 in the bilberry liqueur, and 21 in the blueberry liqueur. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to identify and quantify these compounds, where they were fragmented to the MS<sup>4</sup> fragments. Anthocyanins were the major phenolics group detected in the bilberry liqueurs, but only the second most abundant phenolics group in the blueberry liqueurs. The most abundant phenolics group in the blueberry liqueurs was hydroxycinnamic acids. The lowest content of individual phenolic compounds was for blueberry liqueur made from whole fruit. This study will provide valuable data to consumers in their choice of a more expensive bilberry liqueur or a cheaper blueberry liqueur.
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The aim of this study was to investigate the modulation of polyphenols profile of blackberry purees by soluble dietary fibres (inulin or pectin), during a simulated in vitro gastrointestinal digestion and large intestine fermentation process. Untargeted profiling evidenced that the free phenolic fraction of blackberry puree was characterized mainly by flavonoids, followed by phenolic acids, lignans and other low molecular weight polyphenols, showing clear differences from the bound phenolic fraction detected. This trend could be related to the interactions of dietary fibre and polyphenols, showing synergistic and/or antagonist effect on the bioactivity of polyphenols. On the other hand, in vitro large intestine fermentation of blackberry purees following in vitro gastrointestinal digestion revealed that the highest inclusion level (10% w/w) of soluble dietary fibres was effective in modulating the bioaccessibility of some phenolic classes (mainly phenolic acids, lignans and flavones) characterizing the blackberry puree. In addition, multivariate statistics following metabolomics-based profiling showed that the interaction between fibres and blackberry purees determined a marked modification of both anthocyanins and flavonols during in vitro large intestine fermentation, thus leading to the formation of low-molecular-weight compounds (such as tyrosol, followed by gallic and benzoic acids).
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HPLC-Mass spectrometry analysis of phenolics comparing traditional bilberry and blueberry liqueurs.
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The purpose of this study was to investigate the differences between the phenolics compositions of bilberry and blueberry liqueurs, to determine whether these are comparable. Both bilberry and blueberry liqueurs have the same name on the market, however they differ in phenolic composition and content. A total of 43 compounds were identified, 36 in the bilberry liqueur, and 21 in the blueberry liqueur. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to identify and quantify these compounds, where they were fragmented to the MS<sup>4</sup> fragments. Anthocyanins were the major phenolics group detected in the bilberry liqueurs, but only the second most abundant phenolics group in the blueberry liqueurs. The most abundant phenolics group in the blueberry liqueurs was hydroxycinnamic acids. The lowest content of individual phenolic compounds was for blueberry liqueur made from whole fruit. This study will provide valuable data to consumers in their choice of a more expensive bilberry liqueur or a cheaper blueberry liqueur.
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Anthocyanins are potent antioxidants that may possess chronic disease preventive properties. Here, rapid, reliable, and reproducible solid-phase extraction, high-performance liquid chromatography (HPLC), and mass spectrometry techniques are described for the isolation, separation, and identification of anthocyanins in human plasma and urine. Recoveries of cyanidin-3-glucoside (C3G) were 91% from water, 71% from plasma, and 81% from urine. Intra- and interday variations for C3G extraction were 9 and 9.1% in plasma and 7.1 and 9.1% in urine and were less than 15% for all anthocyanins from a standardized bilberry extract (mirtoselect). Analysis of mirtoselect by HPLC with UV detection produced spectra with 15 peaks compatible with anthocyanin components found in mirtoselect within a total run time of 15 min. Chromatographic analysis of human urine obtained after an oral dose of mirtoselect yielded 19 anthocyanin peaks. Mass spectrometric analysis employing multiple reaction monitoring suggests the presence of unchanged anthocyanins and anthocyanidin glucuronide metabolites.
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HPLC-Mass spectrometry analysis of phenolics comparing traditional bilberry and blueberry liqueurs.
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The purpose of this study was to investigate the differences between the phenolics compositions of bilberry and blueberry liqueurs, to determine whether these are comparable. Both bilberry and blueberry liqueurs have the same name on the market, however they differ in phenolic composition and content. A total of 43 compounds were identified, 36 in the bilberry liqueur, and 21 in the blueberry liqueur. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to identify and quantify these compounds, where they were fragmented to the MS<sup>4</sup> fragments. Anthocyanins were the major phenolics group detected in the bilberry liqueurs, but only the second most abundant phenolics group in the blueberry liqueurs. The most abundant phenolics group in the blueberry liqueurs was hydroxycinnamic acids. The lowest content of individual phenolic compounds was for blueberry liqueur made from whole fruit. This study will provide valuable data to consumers in their choice of a more expensive bilberry liqueur or a cheaper blueberry liqueur.
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The aim of this study was to establish correlation of chemical composition and antioxidant activity of bilberry plants from Montenegro. Total phenolic, tannin, flavonoid, procyanidin and anthocyanin contents were determined in fruits and leaves extracts using spectrophotometric methods, while the measurements of metal content was carried out in an Inductively Coupled Atomic Emission Spectrometer. Qualitative and quantitative analyses of major phenolics were achieved by HPLC. In the investigated extracts, the most abundant phenolic was chlorogenic acid, followed by protocatechuic acid, while resveratrol, isoquercetin, quecetin and hyperoside were also present in significant quantities. Antioxidant potential was evaluated using two in vitro assays-FRAP and DPPH-being in the accordance with the cyclic voltammetry tests, performed as well. The results revealed that all the investigated extracts were rich in phenolic and essential mineral constituents, with significant antioxidant activity, depending on the polyphenolic and mineral contents, which was confirmed by principal component analysis.
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HPLC-Mass spectrometry analysis of phenolics comparing traditional bilberry and blueberry liqueurs.
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The purpose of this study was to investigate the differences between the phenolics compositions of bilberry and blueberry liqueurs, to determine whether these are comparable. Both bilberry and blueberry liqueurs have the same name on the market, however they differ in phenolic composition and content. A total of 43 compounds were identified, 36 in the bilberry liqueur, and 21 in the blueberry liqueur. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to identify and quantify these compounds, where they were fragmented to the MS<sup>4</sup> fragments. Anthocyanins were the major phenolics group detected in the bilberry liqueurs, but only the second most abundant phenolics group in the blueberry liqueurs. The most abundant phenolics group in the blueberry liqueurs was hydroxycinnamic acids. The lowest content of individual phenolic compounds was for blueberry liqueur made from whole fruit. This study will provide valuable data to consumers in their choice of a more expensive bilberry liqueur or a cheaper blueberry liqueur.
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Black tea infusions are one of the most popular beverages across the world. Their extract composition depends on several factors, brewing time being one of the most important determinants. The aim of the present study was to determine the catechin composition of different black tea infusions using a validated LC electrospray ionization time-of-flight MS method. Additionally, total phenolic content (TPC) and antioxidant activity of infusions were evaluated using Folin-Ciocalteu reagent and stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). An optimized LC-MS method enabled the precise identification of the studied catechins [epicatechin (EC), EC gallate (ECG), epigallocatechin (EGC), and epigallocatechin-3-gallate (EGCG)] and gallic acid (GA). The major catechin in all investigated teas was EGC (25.6 mg/100 cm3 after 4 min of brewing). EC was present at the lowest concentration in all extracts. TPC and antiradical scavenging activity were in a good agreement with catechins and GA content. In general, the longer the brewing time, the higher the concentration of catechin, TPC, and antioxidant activity values. However, it should be noted that after 2 min brewing, most phenolics had already been extracted, and extract composition did not significantly change at a prolonged extraction time.
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HPLC-Mass spectrometry analysis of phenolics comparing traditional bilberry and blueberry liqueurs.
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The purpose of this study was to investigate the differences between the phenolics compositions of bilberry and blueberry liqueurs, to determine whether these are comparable. Both bilberry and blueberry liqueurs have the same name on the market, however they differ in phenolic composition and content. A total of 43 compounds were identified, 36 in the bilberry liqueur, and 21 in the blueberry liqueur. High performance liquid chromatography coupled with mass spectrometry (HPLC-MS) was used to identify and quantify these compounds, where they were fragmented to the MS<sup>4</sup> fragments. Anthocyanins were the major phenolics group detected in the bilberry liqueurs, but only the second most abundant phenolics group in the blueberry liqueurs. The most abundant phenolics group in the blueberry liqueurs was hydroxycinnamic acids. The lowest content of individual phenolic compounds was for blueberry liqueur made from whole fruit. This study will provide valuable data to consumers in their choice of a more expensive bilberry liqueur or a cheaper blueberry liqueur.
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Goji berries are now becoming increasingly popular in the human diet due to their potential health benefits. Unscrupulous traders deliberately mislabel with certain origins to gain illegal profits, which seriously affected the consumers' benefits. In this study, an online ultra-performance liquid chromatography-2,2-diphenyl-1 -picrylhydrazyl-photodiode array detector-electrospray ionization-quadrupole time of flight mass was developed for rapid screening and identification of the antioxidants from Goji berry; then, the antioxidants characteristic fingerprint was established and explored in the origins discrimination of Goji berries from China combined with multivariate statistics analysis. As a result, twenty-eight compounds were screened from Goji berry extract, 19 of which were identified by accurate molecular and ultraviolet information according to references. Principal components analysis and partial least squares discrimination analysis achieved the accurate classification from the four regions, eight compounds were selected as origin-related antioxidant markers with variable importance in projection >1 and one-way analysis of variance (P<0.05), including rutin, rutin di-hexose, P-coumaric acid tri-hexose, dicaffeoylquinic acid isomer, Quercetin-rhamno-di-hexoside, peak14, peak16, and peak27. This study provides a feasible strategy for the geographical origins discrimination of Goji berries based on antioxidant ingredients difference and will be helpful for improving the quality control level of Goji berries.
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A genetic algorithm for optimal assembly of pairwise forced-choice questionnaires.
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The use of multidimensional forced-choice questionnaires has been proposed as a means of improving validity in the assessment of non-cognitive attributes in high-stakes scenarios. However, the reduced precision of trait estimates in this questionnaire format is an important drawback. Accordingly, this article presents an optimization procedure for assembling pairwise forced-choice questionnaires while maximizing posterior marginal reliabilities. This procedure is performed through the adaptation of a known genetic algorithm (GA) for combinatorial problems. In a simulation study, the efficiency of the proposed procedure was compared with a quasi-brute-force (BF) search. For this purpose, five-dimensional item pools were simulated to emulate the real problem of generating a forced-choice personality questionnaire under the five-factor model. Three factors were manipulated: (1) the length of the questionnaire, (2) the relative item pool size with respect to the questionnaire's length, and (3) the true correlations between traits. The recovery of the person parameters for each assembled questionnaire was evaluated through the squared correlation between estimated and true parameters, the root mean square error between the estimated and true parameters, the average difference between the estimated and true inter-trait correlations, and the average standard error for each trait level. The proposed GA offered more accurate trait estimates than the BF search within a reasonable computation time in every simulation condition. Such improvements were especially important when measuring correlated traits and when the relative item pool sizes were higher. A user-friendly online implementation of the algorithm was made available to the users.
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Health programs/services are often bundled, allowing for both substitution and complementarity. We adapt Discrete Choice Experiments to capture bundling, with application to a case study of exercise and nutrition; complementarity arises due to the goal of improving health. Our contributions are (1) to present a menu-based choice experiment to explore bundling; (2) to analyse the menu-based data using an extension of the choice set generation model (GenL) to account for correlations between bundles and component singles. A nationally representative sample of 333 Australians chose between a nutrition program only; exercise program only; both nutrition and exercise programs; or their status quo. Overall, we show that by incorporating the menu choice task and introducing the combined alternative, we capture a significant portion of the population seeking both exercise and nutrition components. We estimate a latent class GenL model, and identify two latent classes: Class 1 preferred to choose programs on offer, and Class 2 was more price sensitive and had a stronger preference for staying with their status quo. We show in the post-estimation analysis that heterogeneity in preferences translates into heterogeneity in the way alternatives are bundled, indicating that the combined offering is appealing to specific classes of individuals who prefer bundling. By implementing the menu choice task, researchers and policymakers can effectively identify, cater to and influence the demand for combined exercise and nutrition options, leading to more targeted and impactful interventions in promoting healthier lifestyle choices.
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A genetic algorithm for optimal assembly of pairwise forced-choice questionnaires.
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The use of multidimensional forced-choice questionnaires has been proposed as a means of improving validity in the assessment of non-cognitive attributes in high-stakes scenarios. However, the reduced precision of trait estimates in this questionnaire format is an important drawback. Accordingly, this article presents an optimization procedure for assembling pairwise forced-choice questionnaires while maximizing posterior marginal reliabilities. This procedure is performed through the adaptation of a known genetic algorithm (GA) for combinatorial problems. In a simulation study, the efficiency of the proposed procedure was compared with a quasi-brute-force (BF) search. For this purpose, five-dimensional item pools were simulated to emulate the real problem of generating a forced-choice personality questionnaire under the five-factor model. Three factors were manipulated: (1) the length of the questionnaire, (2) the relative item pool size with respect to the questionnaire's length, and (3) the true correlations between traits. The recovery of the person parameters for each assembled questionnaire was evaluated through the squared correlation between estimated and true parameters, the root mean square error between the estimated and true parameters, the average difference between the estimated and true inter-trait correlations, and the average standard error for each trait level. The proposed GA offered more accurate trait estimates than the BF search within a reasonable computation time in every simulation condition. Such improvements were especially important when measuring correlated traits and when the relative item pool sizes were higher. A user-friendly online implementation of the algorithm was made available to the users.
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A simple linear-operator model both describes and predicts the dynamics of choice that may underlie the matching relation. We measured inter-food choice within components of a schedule that presented seven different pairs of concurrent variable-interval schedules for 12 food deliveries each with no signals indicating which pair was in force. This measure of local choice was accurately described and predicted as obtained reinforcer sequences shifted it to favor one alternative or the other. The effect of a changeover delay was reflected in one parameter, the asymptote, whereas the effect of a difference in overall rate of food delivery was reflected in the other parameter, rate of approach to the asymptote. The model takes choice as a primary dependent variable, not derived by comparison between alternatives-an approach that agrees with the molar view of behaviour.
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A genetic algorithm for optimal assembly of pairwise forced-choice questionnaires.
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The use of multidimensional forced-choice questionnaires has been proposed as a means of improving validity in the assessment of non-cognitive attributes in high-stakes scenarios. However, the reduced precision of trait estimates in this questionnaire format is an important drawback. Accordingly, this article presents an optimization procedure for assembling pairwise forced-choice questionnaires while maximizing posterior marginal reliabilities. This procedure is performed through the adaptation of a known genetic algorithm (GA) for combinatorial problems. In a simulation study, the efficiency of the proposed procedure was compared with a quasi-brute-force (BF) search. For this purpose, five-dimensional item pools were simulated to emulate the real problem of generating a forced-choice personality questionnaire under the five-factor model. Three factors were manipulated: (1) the length of the questionnaire, (2) the relative item pool size with respect to the questionnaire's length, and (3) the true correlations between traits. The recovery of the person parameters for each assembled questionnaire was evaluated through the squared correlation between estimated and true parameters, the root mean square error between the estimated and true parameters, the average difference between the estimated and true inter-trait correlations, and the average standard error for each trait level. The proposed GA offered more accurate trait estimates than the BF search within a reasonable computation time in every simulation condition. Such improvements were especially important when measuring correlated traits and when the relative item pool sizes were higher. A user-friendly online implementation of the algorithm was made available to the users.
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The application of meta-heuristic algorithms for t-way testing has recently become prevalent. Consequently, many useful meta-heuristic algorithms have been developed on the basis of the implementation of t-way strategies (where t indicates the interaction strength). Mixed results have been reported in the literature to highlight the fact that no single strategy appears to be superior compared with other configurations. The hybridization of two or more algorithms can enhance the overall search capabilities, that is, by compensating the limitation of one algorithm with the strength of others. Thus, hybrid variants of the flower pollination algorithm (FPA) are proposed in the current work. Four hybrid variants of FPA are considered by combining FPA with other algorithmic components. The experimental results demonstrate that FPA hybrids overcome the problems of slow convergence in the original FPA and offers statistically superior performance compared with existing t-way strategies in terms of test suite size.
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A genetic algorithm for optimal assembly of pairwise forced-choice questionnaires.
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The use of multidimensional forced-choice questionnaires has been proposed as a means of improving validity in the assessment of non-cognitive attributes in high-stakes scenarios. However, the reduced precision of trait estimates in this questionnaire format is an important drawback. Accordingly, this article presents an optimization procedure for assembling pairwise forced-choice questionnaires while maximizing posterior marginal reliabilities. This procedure is performed through the adaptation of a known genetic algorithm (GA) for combinatorial problems. In a simulation study, the efficiency of the proposed procedure was compared with a quasi-brute-force (BF) search. For this purpose, five-dimensional item pools were simulated to emulate the real problem of generating a forced-choice personality questionnaire under the five-factor model. Three factors were manipulated: (1) the length of the questionnaire, (2) the relative item pool size with respect to the questionnaire's length, and (3) the true correlations between traits. The recovery of the person parameters for each assembled questionnaire was evaluated through the squared correlation between estimated and true parameters, the root mean square error between the estimated and true parameters, the average difference between the estimated and true inter-trait correlations, and the average standard error for each trait level. The proposed GA offered more accurate trait estimates than the BF search within a reasonable computation time in every simulation condition. Such improvements were especially important when measuring correlated traits and when the relative item pool sizes were higher. A user-friendly online implementation of the algorithm was made available to the users.
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Patients play an increasingly active role in the medical decision making process. Hence, methods for eliciting public preferences have become essential tools for enlightening the choices of health authorities. Discrete choice modelling is the most recently applied technique in the field of health. This article deals with the principle, the strengths and the weaknesses of this method. Often used in English-speaking countries, the discrete choice method has several advantages over other elicitation methods since it allows estimation of marginal utilities. Compliance rates are also higher and more information is provided. Considering these qualities, further research should be undertaken on discrete choice modelling in France.
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A genetic algorithm for optimal assembly of pairwise forced-choice questionnaires.
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The use of multidimensional forced-choice questionnaires has been proposed as a means of improving validity in the assessment of non-cognitive attributes in high-stakes scenarios. However, the reduced precision of trait estimates in this questionnaire format is an important drawback. Accordingly, this article presents an optimization procedure for assembling pairwise forced-choice questionnaires while maximizing posterior marginal reliabilities. This procedure is performed through the adaptation of a known genetic algorithm (GA) for combinatorial problems. In a simulation study, the efficiency of the proposed procedure was compared with a quasi-brute-force (BF) search. For this purpose, five-dimensional item pools were simulated to emulate the real problem of generating a forced-choice personality questionnaire under the five-factor model. Three factors were manipulated: (1) the length of the questionnaire, (2) the relative item pool size with respect to the questionnaire's length, and (3) the true correlations between traits. The recovery of the person parameters for each assembled questionnaire was evaluated through the squared correlation between estimated and true parameters, the root mean square error between the estimated and true parameters, the average difference between the estimated and true inter-trait correlations, and the average standard error for each trait level. The proposed GA offered more accurate trait estimates than the BF search within a reasonable computation time in every simulation condition. Such improvements were especially important when measuring correlated traits and when the relative item pool sizes were higher. A user-friendly online implementation of the algorithm was made available to the users.
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There exist several optimization strategies such as sequential quadratic programming (SQP), iterative dynamic programing (IDP), stochastic-based methods such as differential evolution (DE), genetic algorithm (GA), particle swarm optimization (PSA), and ant colony optimization (ACO) for finding optimal feeding profile(s) during fed-batch fermentations. Here in the present study, flower pollination algorithm (FPA) which is inspired by the pollination process in terrestrial flowering plants has been used for the first time to find the optimal feeding profile(s) during fed-batch fermentations. Single control variable, two control variables and state variable bounded problems were chosen to test the robustness of the FPA for optimal control problems. It was observed that FPA is computationally less intensive in comparison with other stochastic strategies. Thus, obtained results were compared to other studies and it has been found that the FPA converged either to newer optima or closer to the established global optimum for the cases studied.
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Inherent functional dependence among cochlear dose surrogates for stereotactic radiosurgery of vestibular schwannomas.
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Various cochlear dose surrogates have been reported as associated with hearing outcome in studies of stereotactic radiosurgery (SRS) for vestibular schwannomas. In this study, we investigated whether an inherent functional relationship exists among these reported surrogates.
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Radiosurgery is a well-established treatment for vestibular schwannomas (VSs), but it is often difficult to identify which tumors will respond to treatment. We sought to determine whether pretreatment or posttreatment tumor apparent diffusion coefficient (ADC) values could predict tumor control in patients undergoing Gamma Knife radiosurgery (GKRS) and whether these values could differentiate between cases of pseudoprogression and cases of true progression in the early posttreatment period.
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Inherent functional dependence among cochlear dose surrogates for stereotactic radiosurgery of vestibular schwannomas.
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Various cochlear dose surrogates have been reported as associated with hearing outcome in studies of stereotactic radiosurgery (SRS) for vestibular schwannomas. In this study, we investigated whether an inherent functional relationship exists among these reported surrogates.
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Normal brain tissue doses have been shown to be strongly apparatus dependent for multi-target stereotactic radiosurgery. In this study, we investigated whether inter-target dose interplay effects across contemporary radiosurgical treatment platforms are responsible for such an observation.
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Inherent functional dependence among cochlear dose surrogates for stereotactic radiosurgery of vestibular schwannomas.
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Various cochlear dose surrogates have been reported as associated with hearing outcome in studies of stereotactic radiosurgery (SRS) for vestibular schwannomas. In this study, we investigated whether an inherent functional relationship exists among these reported surrogates.
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To study the effect of pre-operative hearing level and tumour size on the hearing outcome of hearing preservation surgery for vestibular schwannoma.
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Inherent functional dependence among cochlear dose surrogates for stereotactic radiosurgery of vestibular schwannomas.
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Various cochlear dose surrogates have been reported as associated with hearing outcome in studies of stereotactic radiosurgery (SRS) for vestibular schwannomas. In this study, we investigated whether an inherent functional relationship exists among these reported surrogates.
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Spontaneous tumor shrinkage during wait-and-scan management of sporadic vestibular schwannoma is generally considered an uncommon phenomenon. However, most data informing this understanding stem from single-slice linear tumor measurements taken in the axial imaging plane. The objective of the current work was to characterize the regression capacity of sporadic vestibular schwannomas using volumetric tumor measurements.
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Inherent functional dependence among cochlear dose surrogates for stereotactic radiosurgery of vestibular schwannomas.
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Various cochlear dose surrogates have been reported as associated with hearing outcome in studies of stereotactic radiosurgery (SRS) for vestibular schwannomas. In this study, we investigated whether an inherent functional relationship exists among these reported surrogates.
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The approach to treating vestibular schwannomas ranges from wait-and-scan policies to micro-and radiosurgery. However, in the past few decades, Stereotac tic Radiosurgery (SRS) has emerged as an approved primary treatment option as well. In this review, we have assessed some of the existing literature on the role of SRS in the management of vestibular schwannomas, and to estimate its efficacy in tumour control and conservation of cranial nerve function.
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Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding.
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The conduction of ammonia/ammonium (NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6. The calculated pK(a) values at the Am6 sites in both the AmtB-GlnK complex and isolated AmtB implies the dominance of an uncharged NH3 state. The GlnK protein binding causes a significant downshift in the Am6 pK(a) value of the AmtB. However, this downshift is perfectly compensated by the reorientation of the protein backbone (carbonyl group of Cys312 from the AmtB part) upon AmtB-GlnK complex formation.
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Human aquaporin10 (hAQP10) is a transmembrane facilitator of both water and glycerol transport in the small intestine. This aquaglyceroporin is located in the apical membrane of enterocytes and is believed to contribute to the passage of water and glycerol through these intestinal absorptive cells. Here we overproduced hAQP10 in the yeast Pichia pastoris and observed that the protein is glycosylated at Asn-133 in the extracellular loop C. This finding confirms one of three predicted glycosylation sites for hAQP10, and its glycosylation is unique for the human aquaporins overproduced in this host. Nonglycosylated protein was isolated using both glycan affinity chromatography and through mutating asparagine 133 to a glutamine. All three forms of hAQP10 where found to facilitate the transport of water, glycerol, erythritol, and xylitol, and glycosylation had little effect on functionality. In contrast, glycosylated hAQP10 showed increased thermostability of 3-6 °C compared with the nonglycosylated protein, suggesting a stabilizing effect of the N-linked glycan. Because only one third of hAQP10 was glycosylated yet the thermostability titration was mono-modal, we suggest that the presence of at least one glycosylated protein within each tetramer is sufficient to convey an enhanced structural stability to the remaining hAQP10 protomers of the tetramer.
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Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding.
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The conduction of ammonia/ammonium (NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6. The calculated pK(a) values at the Am6 sites in both the AmtB-GlnK complex and isolated AmtB implies the dominance of an uncharged NH3 state. The GlnK protein binding causes a significant downshift in the Am6 pK(a) value of the AmtB. However, this downshift is perfectly compensated by the reorientation of the protein backbone (carbonyl group of Cys312 from the AmtB part) upon AmtB-GlnK complex formation.
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Integral membrane proteins of the aquaporin family facilitate rapid water flux across cellular membranes in all domains of life. Although the water-conducting pore is clearly defined in an aquaporin monomer, all aquaporins assemble into stable tetramers. In order to investigate the role of protomer⁻protomer interactions, we analyzed the activity of heterotetramers containing increasing fractions of mutated monomers, which have an impaired oligomerization propensity and activity. In order to enforce interaction between the protomers, we designed and analyzed a genetically fused homotetramer of GlpF, the aquaglyceroporin of the bacterium <i>Escherichia coli</i> (<i>E. coli</i>). However, increasing fractions of the oligomerization-impaired mutant GlpF E43A affected the activity of the GlpF heterotetramer in a nearly linear manner, indicating that the reduced protein activity, caused by the introduced mutations, cannot be fully compensated by simply covalently linking the monomers. Taken together, the results underline the importance of exactly positioned monomer⁻monomer contacts in an assembled GlpF tetramer.
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Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding.
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The conduction of ammonia/ammonium (NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6. The calculated pK(a) values at the Am6 sites in both the AmtB-GlnK complex and isolated AmtB implies the dominance of an uncharged NH3 state. The GlnK protein binding causes a significant downshift in the Am6 pK(a) value of the AmtB. However, this downshift is perfectly compensated by the reorientation of the protein backbone (carbonyl group of Cys312 from the AmtB part) upon AmtB-GlnK complex formation.
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In order to understand the functional significance of the transmembrane domain of TrwB, an integral membrane protein involved in bacterial conjugation, the protein was purified in the native, and also as a truncated soluble form (TrwBDeltaN70). The intact protein (TrwB) binds preferentially purine over pyrimidine nucleotides, NTPs over NDPs, and ribo- over deoxyribonucleotides. In contrast, TrwBDeltaN70 binds uniformly all tested nucleotides. The transmembrane domain has the general effect of making the nucleotide binding site(s) less accessible, but more selective. This is in contrast to other membrane proteins in which most of the protein mass, including the catalytic domain, is outside the membrane, but whose activity is not modified by the presence or absence of the transmembrane segment.
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Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding.
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The conduction of ammonia/ammonium (NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6. The calculated pK(a) values at the Am6 sites in both the AmtB-GlnK complex and isolated AmtB implies the dominance of an uncharged NH3 state. The GlnK protein binding causes a significant downshift in the Am6 pK(a) value of the AmtB. However, this downshift is perfectly compensated by the reorientation of the protein backbone (carbonyl group of Cys312 from the AmtB part) upon AmtB-GlnK complex formation.
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Trimethylamine N-oxide (TMAO) is a naturally occurring protecting osmolyte that stabilizes the folded state of proteins and also counteracts the destabilizing effect of urea on protein stability. Experimentally, it has been inferred that TMAO is preferentially excluded from the vicinity of protein surfaces. Here, we combine computer modeling and experimental measurements to gain an understanding of the mechanism of the protecting effect of TMAO on proteins. We have developed an all-atom molecular model for TMAO that captures the exclusion of TMAO from model compounds and protein surfaces, as a consequence of incorporating realistic TMAO-water interactions through osmotic pressure measurements. Osmotic pressure measurements also suggest no significant attraction between urea and TMAO molecules in solution. To obtain an accurate potential for molecular simulations of protein stability in TMAO solutions, we have explored different ways of parametrizing the protein/osmolyte and osmolyte/osmolyte interactions by scaling charges and the strength of Lennard-Jones interactions and carried out equilibrium folding experiments of Trp-cage miniprotein in the presence of TMAO to guide the parametrization. Our calculations suggest a general principle for preferential interaction behavior of cosolvents with protein surfaces--preferentially excluded osmolytes have repulsive self-interaction given by osmotic coefficient φ > 1, while denaturants, in addition to having attractive interactions with the proteins, have favorable self-interaction given by osmotic coefficient φ < 1, to enable preferential accumulation in the vicinity of proteins.
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Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding.
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The conduction of ammonia/ammonium (NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6. The calculated pK(a) values at the Am6 sites in both the AmtB-GlnK complex and isolated AmtB implies the dominance of an uncharged NH3 state. The GlnK protein binding causes a significant downshift in the Am6 pK(a) value of the AmtB. However, this downshift is perfectly compensated by the reorientation of the protein backbone (carbonyl group of Cys312 from the AmtB part) upon AmtB-GlnK complex formation.
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Quaternary ammonium compounds (QACs) are recognized as membrane active agents widely used as biocides. The main purpose of this work was to investigate the influence of the QAC head group and acyl chain length on their permeability-perturbing power and on their affinity for lipidic membranes. Permeability perturbations were assessed by measuring the release of calcein entrapped inside vesicles. The affinity of QACs for bilayers was investigated by isothermal titration calorimetry (ITC). QACs bearing C(16) chain were found to be more efficient to decrease the membrane permeability than their C(12) analogues. On the other hand, the chemical nature of the ammonium head group has practically no influence on the permeability perturbations caused by QACs bearing C(16) chains. It was difficult to assess the partitioning of the QACs between the aqueous and lipid phases since the ITC signals could also be associated to morphological changes such as vesicle aggregation. For the systems for which reliable thermodynamic parameters could be obtained, the Gibbs energy of transfer was similar to that for the micellization. The entropy variation represented the main contribution to the Gibbs energy, indicating that the insertion of QACs inside lipidic bilayers is driven by hydrophobic interactions.
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Reprint of: Prevention and Control of Hypertension: JACC Health Promotion Series.
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Hypertension, the leading risk factor for cardiovascular disease, originates from combined genetic, environmental, and social determinants. Environmental factors include overweight/obesity, unhealthy diet, excessive dietary sodium, inadequate dietary potassium, insufficient physical activity, and consumption of alcohol. Prevention and control of hypertension can be achieved through targeted and/or population-based strategies. For control of hypertension, the targeted strategy involves interventions to increase awareness, treatment, and control in individuals. Corresponding population-based strategies involve interventions designed to achieve a small reduction in blood pressure (BP) in the entire population. Having a usual source of care, optimizing adherence, and minimizing therapeutic inertia are associated with higher rates of BP control. The Chronic Care Model, a collaborative partnership among the patient, provider, and health system, incorporates a multilevel approach for control of hypertension. Optimizing the prevention, recognition, and care of hypertension requires a paradigm shift to team-based care and the use of strategies known to control BP.
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Following a hypertension symposium in Philadelphia in September 2005, a roundtable was convened to discuss the significance of out-of-office blood pressure. Dr. Marvin Moser of the Yale School of Medicine, New Haven, CT, moderated the panel discussion. Participants included Dr. Raymond Townsend of the University of Pennsylvania School of Medicine, Philadelphia, PA, and Dr. Norman Kaplan of the University of Texas Health Science Center in Dallas, Dallas, TX.
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Reprint of: Prevention and Control of Hypertension: JACC Health Promotion Series.
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Hypertension, the leading risk factor for cardiovascular disease, originates from combined genetic, environmental, and social determinants. Environmental factors include overweight/obesity, unhealthy diet, excessive dietary sodium, inadequate dietary potassium, insufficient physical activity, and consumption of alcohol. Prevention and control of hypertension can be achieved through targeted and/or population-based strategies. For control of hypertension, the targeted strategy involves interventions to increase awareness, treatment, and control in individuals. Corresponding population-based strategies involve interventions designed to achieve a small reduction in blood pressure (BP) in the entire population. Having a usual source of care, optimizing adherence, and minimizing therapeutic inertia are associated with higher rates of BP control. The Chronic Care Model, a collaborative partnership among the patient, provider, and health system, incorporates a multilevel approach for control of hypertension. Optimizing the prevention, recognition, and care of hypertension requires a paradigm shift to team-based care and the use of strategies known to control BP.
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The year 2016 has been impacted essentially by the results of the SPRINT trial published in the end of 2015. This study proposed a systolic blood pressure target of <120 mmHg for all high cardiovascular risk patients. In this review, we shall discuss the impact of this trial and the criticisms that have appeared following its publications. These latter will probably limit its practical application. Moreover, we shall discuss the screening of hypertension in children and adolescents and the possible role of drugs lowering uric acid in hypertensive patients with hyperuricemia.
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Reprint of: Prevention and Control of Hypertension: JACC Health Promotion Series.
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Hypertension, the leading risk factor for cardiovascular disease, originates from combined genetic, environmental, and social determinants. Environmental factors include overweight/obesity, unhealthy diet, excessive dietary sodium, inadequate dietary potassium, insufficient physical activity, and consumption of alcohol. Prevention and control of hypertension can be achieved through targeted and/or population-based strategies. For control of hypertension, the targeted strategy involves interventions to increase awareness, treatment, and control in individuals. Corresponding population-based strategies involve interventions designed to achieve a small reduction in blood pressure (BP) in the entire population. Having a usual source of care, optimizing adherence, and minimizing therapeutic inertia are associated with higher rates of BP control. The Chronic Care Model, a collaborative partnership among the patient, provider, and health system, incorporates a multilevel approach for control of hypertension. Optimizing the prevention, recognition, and care of hypertension requires a paradigm shift to team-based care and the use of strategies known to control BP.
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Tsoupras and colleagues have postulated, in a recent review in <i>Nutrients</i>, that the key to reducing the incidence of cardiovascular disease is to control the activities of inflammatory mediators such as platelet-activating factor (PAF) by diet, exercise, and healthy lifestyle choices [...].
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Reprint of: Prevention and Control of Hypertension: JACC Health Promotion Series.
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Hypertension, the leading risk factor for cardiovascular disease, originates from combined genetic, environmental, and social determinants. Environmental factors include overweight/obesity, unhealthy diet, excessive dietary sodium, inadequate dietary potassium, insufficient physical activity, and consumption of alcohol. Prevention and control of hypertension can be achieved through targeted and/or population-based strategies. For control of hypertension, the targeted strategy involves interventions to increase awareness, treatment, and control in individuals. Corresponding population-based strategies involve interventions designed to achieve a small reduction in blood pressure (BP) in the entire population. Having a usual source of care, optimizing adherence, and minimizing therapeutic inertia are associated with higher rates of BP control. The Chronic Care Model, a collaborative partnership among the patient, provider, and health system, incorporates a multilevel approach for control of hypertension. Optimizing the prevention, recognition, and care of hypertension requires a paradigm shift to team-based care and the use of strategies known to control BP.
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In 1953 when the Nordic School of Public Health was founded, the aim of public health programmes was disease prevention more than health promotion. This was not unusual, since at this time health usually was seen as the opposite of disease and illness. However, with the Ottawa Charter of 1986, the World Health Organization made a crucial change to view health not as a goal in itself but as the means to a full life. In this way, health promotion became a first priority and fundamental action for the modern society. This insight eventually reached NHV and in 2002 - 50 years after the foundation - an associate professorship was established with a focus on health promotion. Nevertheless, the concept of health promotion had been integrated with or mentioned in courses run prior to the new post. Subsequently, a wide spectrum of courses in health promotion was introduced, such as 'Empowerment for Child and Adolescent Health Promotion', 'Salutogenesis--from theory to practice' and 'Health, Stress and Coping'. More than half of all doctoral theses undertaken at NHV during these years had health promotion as their theme. As a derivative, the Nordic Health Promotion Research Network (NHPRN) was established in 2007 with bi-annual meetings at NHV.
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Reprint of: Prevention and Control of Hypertension: JACC Health Promotion Series.
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Hypertension, the leading risk factor for cardiovascular disease, originates from combined genetic, environmental, and social determinants. Environmental factors include overweight/obesity, unhealthy diet, excessive dietary sodium, inadequate dietary potassium, insufficient physical activity, and consumption of alcohol. Prevention and control of hypertension can be achieved through targeted and/or population-based strategies. For control of hypertension, the targeted strategy involves interventions to increase awareness, treatment, and control in individuals. Corresponding population-based strategies involve interventions designed to achieve a small reduction in blood pressure (BP) in the entire population. Having a usual source of care, optimizing adherence, and minimizing therapeutic inertia are associated with higher rates of BP control. The Chronic Care Model, a collaborative partnership among the patient, provider, and health system, incorporates a multilevel approach for control of hypertension. Optimizing the prevention, recognition, and care of hypertension requires a paradigm shift to team-based care and the use of strategies known to control BP.
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Importance of strict blood pressure control in hypertension is stressed in guidelines. But rates of achieving target blood pressure in several surveillance studies are less than 50%. Poor compliance to medication, life style related problems such as obesity, excess salt and alcohol intake, sleep apnea and coadministered drugs such as NSAIDs or licorice, and physicians attitude to blood pressure control can be reasons for resistant hypertension. First step to improve the blood pressure control status is identifying reasons. To solve the identified problems, comprehensive approaches by health professionals are necessary.
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Preventing a data breach from becoming a disaster.
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Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.
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Watch this space! After a varied career and many happy years at Cats Protection, Maggie Roberts took a new turn and, not one to shy away from a challenge, she started a new venture and did a standup comedy course.
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Preventing a data breach from becoming a disaster.
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Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.
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Fundamental misunderstandings about classification can lead scientists down unproductive or dangerous paths, argue Jeffrey Parsons and Yair Wand.
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Preventing a data breach from becoming a disaster.
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Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.
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On 7 July 2008, Wilson Gumbura sought judicial review of a decision by an enforcement officer not to defer his removal from Canada until a decision had been made on his humanitarian and compassionate application.
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Preventing a data breach from becoming a disaster.
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Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.
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Disaster is a risk which health professionals must learn to manage without ever being sure that they will be confronted with it. A health crisis will have potentially significant repercussions within healthcare facilities. Emergency response plans as well as a shared culture enable healthcare workers to face a crisis by being organised.
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Preventing a data breach from becoming a disaster.
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Organisations have traditionally dealt with data breaches by investing in protective measures without a great deal of attention to mitigation of breach consequences and response. Conversely, business continuity (BC) planning has traditionally focused on mitigating disasters, not on preventing them. From a BC planning perspective, organisations need to assume that a data breach is inevitable and plan accordingly. The spate of data breaches in these past few years hit many organisations that were well protected. Those that suffered disastrous consequences as a result of a data breach lacked effective mitigation and response, not protection. The complexity and speed of an effective data breach response require that detailed planning takes place in advance of a breach.
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While the healthcare industry is undergoing disruptive digital transformation, data breaches involving health information are not usually the result of integration of new technologies. Based on published industry reports, fundamental security safeguards are still considered to be lacking with many documented data breaches occurring as the result of device and equipment theft, human error, hacking, ransomware attacks and misuse. Health information is considered to be one of the most attractive targets for cybercriminals due to its inherent sensitivity, but digital investigations of incidents involving health information are often constrained by the lack of the necessary infrastructure forensic readiness. Following the analysis of healthcare data breach causes and threats, we describe the associated digital forensic readiness challenges in the context of the most significant incident causes. With specific focus on privilege misuse, we present a conceptual architecture for forensic audit logging to assist with capture of the relevant digital artefacts in support of possible future digital investigations.
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A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma.
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With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.
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There is insufficient evidence concerning the effect of preoperative continuation of antiplatelet therapy (APT) on intraoperative and postoperative bleeding during liver resection. This study investigated the efficacy and safety of preoperative aspirin continuation on bleeding complications during or after liver resection using propensity score matching (PSM).
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A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma.
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With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.
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To compare the effects of laparoscopic hepatectomy (LH) versus open hepatectomy (OH) on the short-term and long-term outcomes of patients with intrahepatic cholangiocarcinoma (ICC) through a meta-analysis of studies using propensity score-matched cohorts.
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A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma.
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With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.
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Propensity-score methods are increasingly being used to reduce the impact of treatment-selection bias in the estimation of treatment effects using observational data. Commonly used propensity-score methods include covariate adjustment using the propensity score, stratification on the propensity score, and propensity-score matching. Empirical and theoretical research has demonstrated that matching on the propensity score eliminates a greater proportion of baseline differences between treated and untreated subjects than does stratification on the propensity score. However, the analysis of propensity-score-matched samples requires statistical methods appropriate for matched-pairs data. We critically evaluated 47 articles that were published between 1996 and 2003 in the medical literature and that employed propensity-score matching. We found that only two of the articles reported the balance of baseline characteristics between treated and untreated subjects in the matched sample and used correct statistical methods to assess the degree of imbalance. Thirteen (28 per cent) of the articles explicitly used statistical methods appropriate for the analysis of matched data when estimating the treatment effect and its statistical significance. Common errors included using the log-rank test to compare Kaplan-Meier survival curves in the matched sample, using Cox regression, logistic regression, chi-squared tests, t-tests, and Wilcoxon rank sum tests in the matched sample, thereby failing to account for the matched nature of the data. We provide guidelines for the analysis and reporting of studies that employ propensity-score matching.
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A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma.
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With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.
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This retrospective study investigated the predictive value of the Controlling Nutritional Status (CONUT) score in patients with intermediate-stage hepatocellular carcinoma (HCC) who received transarterial chemoembolization (TACE). Nomograms were developed to predict progression-free and overall survival (PFS, OS). The medical data of 228 patients with HCC and treated with TACE were collected. The patients were apportioned to 2 groups according to CONUT score: low or high (<4, ≥4). Univariate and multivariate analyses were performed using Cox regression for OS and PFS. OS and PFS were estimated by the Kaplan-Meier curve and compared with the log-rank test. Nomograms were constructed to predict patient OS and PFS. The nomograms were evaluated for accuracy, discrimination, and efficiency. The cut-off value of CONUT score was 4. The higher the CONUT score, the worse the survival; Kaplan-Meier curves showed significant differences in OS and PFS between the low and high CONUT score groups (<i>P</i> = 0·033, 0·047). The nomograms including CONUT, based on the prognostic factors determined by the univariate and multivariate analyses, to predict survival in HCC after TACE were generated. The CONUT score is an important prognostic factor for both OS and PFS for patients with intermediate HCC who underwent TACE. The cut-off value of the CONUT score was 4. A high CONUT score suggests poor survival outcomes. Nomograms generated based on the CONUT score were good models to predict patient OS and PFS.
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A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma.
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With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.
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Propensity score matching is widely used to determine the effects of treatments in observational studies. Competing risk survival data are common to medical research. However, there is a paucity of propensity score matching studies related to competing risk survival data with missing causes of failure. In this study, we provide guidelines for estimating the treatment effect on the cumulative incidence function when using propensity score matching on competing risk survival data with missing causes of failure. We examined the performances of different methods for imputing the data with missing causes. We then evaluated the gain from the missing cause imputation in an extensive simulation study and applied the proposed data imputation method to the data from a study on the risk of hepatocellular carcinoma in patients with chronic hepatitis B and chronic hepatitis C.
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Scurvy in a patient with AIDS: case report.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30 kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
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Case Report.
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Scurvy in a patient with AIDS: case report.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30 kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
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A case report is presented.
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Scurvy in a patient with AIDS: case report.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30 kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
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Cryptococcosis is the most common fungal disease in HIV-infected persons. It is known as the AIDS-defining illness for 60-70% of HIV-infected patients. Before antiretroviral therapy (ARV) was discovered, fungal and other opportunistic infections were a major problem for people with advanced HIV/AIDS. Presented here is a case of a 43-year-old man who was newly diagnosed HIV, in which he was admitted due to shortness of breath and decreased consciousness. His clinical symptoms, physical examination, laboratory and radiologic findings indicated a <i>Cryptococcus neoformans</i> infection. The patient had received treatment using anti-fungal and ARV that showed a clinical improvement during observation.
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Scurvy in a patient with AIDS: case report.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30 kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
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We report a 3-year-old boy with unilateral proptosis, painful swelling of the right thigh and aphasia. He had radiographic evidence of scurvy in the limbs and bilateral frontal extradural hematomas with a mass lesion in the left orbit on MRI. He was treated with vitamin C and on follow-up 8 weeks later had recovered with no evidence of the orbital mass on clinical or radiological study. Scurvy manifesting as proptosis and extradural hematoma is rare.
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Scurvy in a patient with AIDS: case report.
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We report the case of a 35-year-old homeless alcoholic and illicit drug user, with AIDS, who was admitted to the emergency unit complaining of asthenia and a weight loss of 30 kg over the preceding three months. Clinical and laboratory data confirmed a diagnosis of marasmus, bacterial pneumonia, chorioretinitis caused by Toxoplasma gondii and oral Candida infection. The patient also presented loss of tongue papillae, gingival hypertrophy, perifollicular hyperkeratosis and hemorrhage, coiled, corkscrew-like hair, anemia, hypoalbuminemia, increased C-reactive protein levels and low serum vitamin C levels. The patient developed severe gastric hemorrhage, with hemodynamic instability and terminal disseminated intravascular coagulopathy.
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A 36-year-old African American man with no medical history presented with a recent history of cough and dyspnoea. Initial chest imaging revealed diffuse bilateral lung infiltrates. A subsequent HIV test resulted positive, and he was presumptively diagnosed with AIDS, later confirmed by a CD4 of 88 cells/mm<sup>3</sup> Empiric therapy with trimethoprim-sulfamethoxazole was initiated for presumed <i>Pneumocystis jirovecii</i> pneumonia. The patient's clinical status deteriorated despite treatment. Further workup with chest CT, bronchoscopy and skin biopsy led to a diagnosis of Kaposi sarcoma with pulmonary involvement. Highly active antiretroviral therapy therapy was initiated, along with plans to start chemotherapy. However, the patient's clinical status rapidly declined, leading to respiratory failure and eventual death. This case underlines the importance of maintaining a broad differential in immunocompromised patients presenting with respiratory symptoms.
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Validation of the Alcohol Smoking and Substance Involvement Screening Test (ASSIST) in acute psychiatric inpatients.
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The aims of this study were to examine the psychometric properties of The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) in psychiatric inpatients, due to the scarcity of screening instruments validated in this population. Patients from Hospital Clínic's psychiatric ward (n = 202) completed: ASSIST, Addiction Severity Index (ASI), MINI-International Neuropsychiatric Interview (MINI), Alcohol Use Disorders Identification Test (AUDIT), Fagerström Test for Nicotine Dependence (FTND), Severity of Dependence Scale (SDS), and Drug Abuse Screening Test (DAST). Reliability and validity evidences based on internal structure (Exploratory and Confirmatory Factor Analyses) and on the relation to other variables were obtained. Excellent internal consistency was found for Total Substance Involvement (TSI) (α = .92 and ω = .93) and for Specific Substance Involvement (SSI) scores (α = .88 - .96 and ω = .89 - .95). Analysis of internal structure for tobacco, alcohol and cannabis subscales resulted in unidimensional models with adequate goodness-of-fit indices. ASSIST scores were significantly correlated with those of ASI (r = .795 to r = .953), AUDIT (r = .864), FTND (r = .808), DAST (r = .831), SDS (r = .519) and with "number of diagnoses of abuse/dependence" in MINI-Plus (TSI: r = .857 to r = .862; SSI: r = .646 to r = .834). Receiver operating characteristic analysis (ROC) and Mann-Whitney's U test found good discriminative validity evidences. ASSIST scores showed good reliability and there were validity evidences that support its use for identifying risk levels of tobacco, alcohol and other substance use in psychiatric patients.
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Early detection of risky alcohol use and severe alcohol use disorders (AUDs) is crucial to avoid adverse health consequences. The German "Guidelines on Screening, Diagnosis and Treatment of Alcohol Use Disorders" recommend to routinely screen patients for hazardous alcohol use and to subsequently conduct brief interventions, for example in primary healthcare. For severe AUDs, provision of withdrawal treatment is recommended in inpatient settings if complications are anticipated.
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Validation of the Alcohol Smoking and Substance Involvement Screening Test (ASSIST) in acute psychiatric inpatients.
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The aims of this study were to examine the psychometric properties of The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) in psychiatric inpatients, due to the scarcity of screening instruments validated in this population. Patients from Hospital Clínic's psychiatric ward (n = 202) completed: ASSIST, Addiction Severity Index (ASI), MINI-International Neuropsychiatric Interview (MINI), Alcohol Use Disorders Identification Test (AUDIT), Fagerström Test for Nicotine Dependence (FTND), Severity of Dependence Scale (SDS), and Drug Abuse Screening Test (DAST). Reliability and validity evidences based on internal structure (Exploratory and Confirmatory Factor Analyses) and on the relation to other variables were obtained. Excellent internal consistency was found for Total Substance Involvement (TSI) (α = .92 and ω = .93) and for Specific Substance Involvement (SSI) scores (α = .88 - .96 and ω = .89 - .95). Analysis of internal structure for tobacco, alcohol and cannabis subscales resulted in unidimensional models with adequate goodness-of-fit indices. ASSIST scores were significantly correlated with those of ASI (r = .795 to r = .953), AUDIT (r = .864), FTND (r = .808), DAST (r = .831), SDS (r = .519) and with "number of diagnoses of abuse/dependence" in MINI-Plus (TSI: r = .857 to r = .862; SSI: r = .646 to r = .834). Receiver operating characteristic analysis (ROC) and Mann-Whitney's U test found good discriminative validity evidences. ASSIST scores showed good reliability and there were validity evidences that support its use for identifying risk levels of tobacco, alcohol and other substance use in psychiatric patients.
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Major depression, anxiety disorders, and post-traumatic stress disorder (PTSD) are among the most prevalent comorbid mental disorders in youth addiction treatment. Hence, screening for these internalizing disorders should be part of the standard routine at intake in substance use disorder treatment. We investigated the usefulness of the Depression, Anxiety and Stress Scale (DASS-21) as a screener for this purpose.
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Validation of the Alcohol Smoking and Substance Involvement Screening Test (ASSIST) in acute psychiatric inpatients.
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The aims of this study were to examine the psychometric properties of The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) in psychiatric inpatients, due to the scarcity of screening instruments validated in this population. Patients from Hospital Clínic's psychiatric ward (n = 202) completed: ASSIST, Addiction Severity Index (ASI), MINI-International Neuropsychiatric Interview (MINI), Alcohol Use Disorders Identification Test (AUDIT), Fagerström Test for Nicotine Dependence (FTND), Severity of Dependence Scale (SDS), and Drug Abuse Screening Test (DAST). Reliability and validity evidences based on internal structure (Exploratory and Confirmatory Factor Analyses) and on the relation to other variables were obtained. Excellent internal consistency was found for Total Substance Involvement (TSI) (α = .92 and ω = .93) and for Specific Substance Involvement (SSI) scores (α = .88 - .96 and ω = .89 - .95). Analysis of internal structure for tobacco, alcohol and cannabis subscales resulted in unidimensional models with adequate goodness-of-fit indices. ASSIST scores were significantly correlated with those of ASI (r = .795 to r = .953), AUDIT (r = .864), FTND (r = .808), DAST (r = .831), SDS (r = .519) and with "number of diagnoses of abuse/dependence" in MINI-Plus (TSI: r = .857 to r = .862; SSI: r = .646 to r = .834). Receiver operating characteristic analysis (ROC) and Mann-Whitney's U test found good discriminative validity evidences. ASSIST scores showed good reliability and there were validity evidences that support its use for identifying risk levels of tobacco, alcohol and other substance use in psychiatric patients.
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Psychiatric comorbidity in alcohol use disorders is clearly established, however most studies ignore data on psychiatric symptom counts that do not meet criteria for a diagnosis. We examined psychiatric symptom counts and psychological measures in the domains of anxiety, mood and externalizing pathology in 48 long-term abstinent alcoholics (LTAA) compared to 48 age/gender comparable light/non-drinking controls (NC).
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Validation of the Alcohol Smoking and Substance Involvement Screening Test (ASSIST) in acute psychiatric inpatients.
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The aims of this study were to examine the psychometric properties of The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) in psychiatric inpatients, due to the scarcity of screening instruments validated in this population. Patients from Hospital Clínic's psychiatric ward (n = 202) completed: ASSIST, Addiction Severity Index (ASI), MINI-International Neuropsychiatric Interview (MINI), Alcohol Use Disorders Identification Test (AUDIT), Fagerström Test for Nicotine Dependence (FTND), Severity of Dependence Scale (SDS), and Drug Abuse Screening Test (DAST). Reliability and validity evidences based on internal structure (Exploratory and Confirmatory Factor Analyses) and on the relation to other variables were obtained. Excellent internal consistency was found for Total Substance Involvement (TSI) (α = .92 and ω = .93) and for Specific Substance Involvement (SSI) scores (α = .88 - .96 and ω = .89 - .95). Analysis of internal structure for tobacco, alcohol and cannabis subscales resulted in unidimensional models with adequate goodness-of-fit indices. ASSIST scores were significantly correlated with those of ASI (r = .795 to r = .953), AUDIT (r = .864), FTND (r = .808), DAST (r = .831), SDS (r = .519) and with "number of diagnoses of abuse/dependence" in MINI-Plus (TSI: r = .857 to r = .862; SSI: r = .646 to r = .834). Receiver operating characteristic analysis (ROC) and Mann-Whitney's U test found good discriminative validity evidences. ASSIST scores showed good reliability and there were validity evidences that support its use for identifying risk levels of tobacco, alcohol and other substance use in psychiatric patients.
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To assess recovery of alcohol-related neuropsychological deficits in a group of patients with pure severe alcohol use disorder (AUD) during a detoxification program using the Brief Evaluation of Alcohol-Related Neuropsychological Impairment (BEARNI) test.
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Validation of the Alcohol Smoking and Substance Involvement Screening Test (ASSIST) in acute psychiatric inpatients.
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The aims of this study were to examine the psychometric properties of The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) in psychiatric inpatients, due to the scarcity of screening instruments validated in this population. Patients from Hospital Clínic's psychiatric ward (n = 202) completed: ASSIST, Addiction Severity Index (ASI), MINI-International Neuropsychiatric Interview (MINI), Alcohol Use Disorders Identification Test (AUDIT), Fagerström Test for Nicotine Dependence (FTND), Severity of Dependence Scale (SDS), and Drug Abuse Screening Test (DAST). Reliability and validity evidences based on internal structure (Exploratory and Confirmatory Factor Analyses) and on the relation to other variables were obtained. Excellent internal consistency was found for Total Substance Involvement (TSI) (α = .92 and ω = .93) and for Specific Substance Involvement (SSI) scores (α = .88 - .96 and ω = .89 - .95). Analysis of internal structure for tobacco, alcohol and cannabis subscales resulted in unidimensional models with adequate goodness-of-fit indices. ASSIST scores were significantly correlated with those of ASI (r = .795 to r = .953), AUDIT (r = .864), FTND (r = .808), DAST (r = .831), SDS (r = .519) and with "number of diagnoses of abuse/dependence" in MINI-Plus (TSI: r = .857 to r = .862; SSI: r = .646 to r = .834). Receiver operating characteristic analysis (ROC) and Mann-Whitney's U test found good discriminative validity evidences. ASSIST scores showed good reliability and there were validity evidences that support its use for identifying risk levels of tobacco, alcohol and other substance use in psychiatric patients.
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Substance use disorders (SUD) and associated problems are highly prevalent but often undetected in patients with Severe Mental Illness (SMI). This study investigates the prevalence, under-detection, and variables associated with a high risk of SUD in a Dutch sample of adult outpatient SMI patients (N = 83).
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Using poly(l-lactic acid) and poly(ɛ-caprolactone) blends to fabricate self-expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair.
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Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 295-305, 2019.
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In this study, bioscaffolds using poly(DL-lactide-co-glycolide) acid (PLGA) were fabricated and studied. The gas foaming/salt leaching technique in a batch foaming setup was employed, and the effects of material composition of PLGA on the morphology and mechanical properties using this process were investigated. Two material compositions of PLGA 50/50 and 85/15 were used, and characterization of scaffolds fabricated with these materials showed that a lower relative density can be achieved with an increasing poly(DL-lactide) acid (PDLLA) content; however, higher open-cell porosity was obtained with lower PDLLA content. Furthermore, the effect of PLGA composition on modulus of the scaffolds was minor.
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Using poly(l-lactic acid) and poly(ɛ-caprolactone) blends to fabricate self-expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair.
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Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 295-305, 2019.
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Co- and terpolyesters based on succinic acid and isosorbide in combination with other renewable monomers such as 2,3-butanediol, 1,3-propanediol, and citric acid were synthesized and characterized. Linear polyesters were obtained via melt polycondensation of nonactivated dicarboxylic acids with OH functional monomers. Polymer end functionality (i.e., hydroxyl or carboxylic acid) was controlled by adjusting the monomer stoichiometry. The glass transition temperatures of the resulting polyesters could be effectively adjusted by varying the polymer composition and molar mass. By adding polyfunctional monomers such as trimethylolpropane or citric acid, polyesters with enhanced functionality were obtained. These biobased polyesters displayed functionalities and Tg values in the appropriate range for (powder) coating applications. The polyesters were cross-linked using conventional curing agents. Coatings from branched polyesters--hydroxyl as well as acid functional--showed significantly improved mechanical and chemical resistance compared to those formulated from linear polymers. These renewable polyesters proved to be suitable materials for coating applications with respect to solvent resistance, impact resistance, and hardness.
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Using poly(l-lactic acid) and poly(ɛ-caprolactone) blends to fabricate self-expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair.
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Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 295-305, 2019.
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The objective of this study was to fabricate a novel nano-bioceramics incorporated lysozyme poly (d, l-lactide-co-glycolide) (PLGA) microsphere.
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Using poly(l-lactic acid) and poly(ɛ-caprolactone) blends to fabricate self-expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair.
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Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 295-305, 2019.
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An efficient and metal-catalyst free method of glycopolymer synthesis via thiol/para-fluorine "click" reaction was used to graft acetylated 1-thio-β-D-glucopyranose and 1-thio-β-D-galactopyranose onto a homopolymer of pentafluorostyrene (PFS) as well as onto a block copolymer of styrene and PFS. Subsequent deprotection of the carbohydrate moieties yielded well-defined, sugar-modified polymers (PDI < 1.2). The prepared polymers were not cytotoxic against 3T3 fibroblasts and MC3T3-E1 preosteoblasts. Furthermore, the water-insoluble copolymers were drop-cast and examined as synthetic biocompatible coatings on poly(propylene) substrates for culturing the investigated cell types. Both fibro- and preosteoblasts showed stable adhesion and proliferation on the glycopolymer-coated surfaces.
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Using poly(l-lactic acid) and poly(ɛ-caprolactone) blends to fabricate self-expanding, watertight and biodegradable surgical patches for potential fetoscopic myelomeningocele repair.
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Our study focuses on the development and characterization of a self-expanding, watertight and biodegradable patch for fetoscopic myelomeningocele (MMC) prenatal repair. We fabricated poly(l-lactic acid) (PLA) and poly(ɛ-caprolactone) (PCL) blend films by solution casting. Formulation c with average glass transition temperature of 37.6 ± 1.2°C was chosen for temporospatial recovery. Favorable results from surface studies reflected homogeneous dispersion of polymers in the blend. The cytotoxicity was studied in human foreskin fibroblasts. The blend film was cytocompatible, evidenced by matching percentage of live cells in exposed and control solutions. Subsequently, liquid water permeability experiments confirmed watertight nature of films. Finally, in vitro degradation was investigated in phosphate buffered saline (PBS) and amniotic fluid (AF) separately for 16 weeks. Similar weight loss (n = 6, p = 0.912) and significantly different (n = 3, p = 0.025) surface roughness was observed in PBS and AF, respectively, at 16 weeks. Functional group analysis displayed increasing carbonyl and hydroxyl bonds in PBS and AF, respectively, over time, indicating progression of hydrolytic degradation. Favorable characterization results provide strong evidence to employ PLA-PCL blend films as surgical patches in fetoscopic MMC repair. Designed patch serves as standalone system to successfully tackle impending hurdles of MMC repair and proves to be a superior alternative compared to existing patches. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 295-305, 2019.
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A novel biocompatible dural substitute created using fibrin glue and polyglycolic acid nonwoven fabric was examined for closing ability and histology.
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Remission in rheumatoid arthritis: wishful thinking or clinical reality?
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To review the concept of remission in rheumatoid arthritis (RA), as defined by the Food and Drug Administration (FDA), the American College of Rheumatology (ACR), and the European League Against Rheumatism (EULAR). To delineate differences between significant clinical improvements, very low disease activity, and the achievement of true remission. To evaluate the prevalence of these outcomes with biologic therapy and traditional disease-modifying antirheumatic drugs (DMARD) regimens.
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Accurate diagnosis of rheumatoid arthritis may be difficult early in its course and demands high clinical suspicion, astute examination, and appropriate investigations. Early use of disease-modifying antirheumatic drugs and biologics has improved outcomes but requires close monitoring of disease course and adverse events.
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Remission in rheumatoid arthritis: wishful thinking or clinical reality?
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To review the concept of remission in rheumatoid arthritis (RA), as defined by the Food and Drug Administration (FDA), the American College of Rheumatology (ACR), and the European League Against Rheumatism (EULAR). To delineate differences between significant clinical improvements, very low disease activity, and the achievement of true remission. To evaluate the prevalence of these outcomes with biologic therapy and traditional disease-modifying antirheumatic drugs (DMARD) regimens.
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Over the course of the past 30 years the outlook for patients with rheumatic arthritis (RA) has changed substantially. The careful "wait-and-see" attitude of rheumatologists of the past has been replaced by early and intensive intervention in patients with early RA. These days it is possible to bring about remission in half of all patients with, among others, the new medicines-- the "biologicals". Auto-antibodies are now detectable in the pre-clinical phase of RA; this means that in the future it will be possible to trace people with a raised risk of developing RA.
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Remission in rheumatoid arthritis: wishful thinking or clinical reality?
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To review the concept of remission in rheumatoid arthritis (RA), as defined by the Food and Drug Administration (FDA), the American College of Rheumatology (ACR), and the European League Against Rheumatism (EULAR). To delineate differences between significant clinical improvements, very low disease activity, and the achievement of true remission. To evaluate the prevalence of these outcomes with biologic therapy and traditional disease-modifying antirheumatic drugs (DMARD) regimens.
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Remission has become a realistic goal in the management of rheumatoid arthritis(RA). The 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria focus on early-stage RA, and were specifically designed to address the deficiencies in the 1987 criteria, primarily a lack of sensitivity. However, these criteria are not intended for diagnosis in routine clinical care. RA should be suspected in the patient who presents with inflammatory polyarthritis. Initial evaluation of such patients requires a careful history and physical examination, along with select laboratory testing to identify features that are characteristic of RA or that suggest an alternative diagnosis. Radiographs should also be performed. Further research will eventually lead to more reliable diagnostic and classification criteria for new-onset RA.
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Remission in rheumatoid arthritis: wishful thinking or clinical reality?
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To review the concept of remission in rheumatoid arthritis (RA), as defined by the Food and Drug Administration (FDA), the American College of Rheumatology (ACR), and the European League Against Rheumatism (EULAR). To delineate differences between significant clinical improvements, very low disease activity, and the achievement of true remission. To evaluate the prevalence of these outcomes with biologic therapy and traditional disease-modifying antirheumatic drugs (DMARD) regimens.
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Treatment to a target level of a variable known to be associated with bad disease outcome is a concept that has been applied for many years in several specialties. In rheumatology this has not been the case, primarily because of the complexity of measures assessing disease activity of RA and insufficient knowledge of optimal strategies. Meanhwile, however, our insights into the devastating role of active disease have expanded. In parallel, the use of composite measures of disease activity to control patients tightly and adapt therapy accordingly has provided the evidence that treating RA to a target value of low disease activity or remission conveys significant benefit. The background of the treat-to-target concept and future aspects are discussed.
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Remission in rheumatoid arthritis: wishful thinking or clinical reality?
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To review the concept of remission in rheumatoid arthritis (RA), as defined by the Food and Drug Administration (FDA), the American College of Rheumatology (ACR), and the European League Against Rheumatism (EULAR). To delineate differences between significant clinical improvements, very low disease activity, and the achievement of true remission. To evaluate the prevalence of these outcomes with biologic therapy and traditional disease-modifying antirheumatic drugs (DMARD) regimens.
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Remission is the ultimate goal of the treatment of rheumatoid arthritis (RA). However, the diagnosis of remission might still be vague. Musculoskeletal ultrasound (US) seems to effectively assess synovitis, effusion and bone damage. Thus, its role could be relevant for the diagnosis, monitoring or detection of relapse in the follow-up of RA in remission. The goal of this review of the literature was to clarify the added value of ultrasonography during remission.
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Sonoluminescence and sonochemiluminescence from a microreactor.
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Micromachined pits on a substrate can be used to nucleate and stabilize microbubbles in a liquid exposed to an ultrasonic field. Under suitable conditions, the collapse of these bubbles can result in light emission (sonoluminescence, SL). Hydroxyl radicals (OH()) generated during bubble collapse can react with luminol to produce light (sonochemiluminescence, SCL). SL and SCL intensities were recorded for several regimes related to the pressure amplitude (low and high acoustic power levels) at a given ultrasonic frequency (200kHz) for pure water, and aqueous luminol and propanol solutions. Various arrangements of pits were studied, with the number of pits ranging from no pits (comparable to a classic ultrasound reactor), to three-pits. Where there was more than one pit present, in the high pressure regime the ejected microbubbles combined into linear (two-pits) or triangular (three-pits) bubble clouds (streamers). In all situations where a pit was present on the substrate, the SL was intensified and increased with the number of pits at both low and high power levels. For imaging SL emitting regions, Argon (Ar) saturated water was used under similar conditions. SL emission from aqueous propanol solution (50mM) provided evidence of transient bubble cavitation. Solutions containing 0.1mM luminol were also used to demonstrate the radical production by attaining the SCL emission regions.
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The relevant length scales in sub-nanometer amplitude surface acoustic wave-driven acoustic streaming are demonstrated. We demonstrate the absence of any physical limitations preventing the downscaling of SAW-driven internal streaming to nanoliter microreactors and beyond by extending SAW microfluidics up to operating frequencies in the GHz range. This method is applied to nanoliter scale fluid mixing.
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Sonoluminescence and sonochemiluminescence from a microreactor.
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Micromachined pits on a substrate can be used to nucleate and stabilize microbubbles in a liquid exposed to an ultrasonic field. Under suitable conditions, the collapse of these bubbles can result in light emission (sonoluminescence, SL). Hydroxyl radicals (OH()) generated during bubble collapse can react with luminol to produce light (sonochemiluminescence, SCL). SL and SCL intensities were recorded for several regimes related to the pressure amplitude (low and high acoustic power levels) at a given ultrasonic frequency (200kHz) for pure water, and aqueous luminol and propanol solutions. Various arrangements of pits were studied, with the number of pits ranging from no pits (comparable to a classic ultrasound reactor), to three-pits. Where there was more than one pit present, in the high pressure regime the ejected microbubbles combined into linear (two-pits) or triangular (three-pits) bubble clouds (streamers). In all situations where a pit was present on the substrate, the SL was intensified and increased with the number of pits at both low and high power levels. For imaging SL emitting regions, Argon (Ar) saturated water was used under similar conditions. SL emission from aqueous propanol solution (50mM) provided evidence of transient bubble cavitation. Solutions containing 0.1mM luminol were also used to demonstrate the radical production by attaining the SCL emission regions.
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Seismic velocities and elastic moduli of rocks are known to vary significantly with applied stress, which indicates that these materials exhibit nonlinear elasticity. Monochromatic waves in nonlinear elastic media are known to generate higher harmonics and combinational frequencies. Such effects have the potential to be used for broadening the frequency band of seismic sources, characterization of the subsurface, and safety monitoring of civil engineering infrastructure. However, knowledge on nonlinear seismic effects is still scarce, which impedes the development of their practical applications. To explore the potential of nonlinear seismology, we performed three experiments: two in the field and one in the laboratory. The first field experiment used two vibroseis sources generating signals with two different monochromatic frequencies. The second field experiment used a surface orbital vibrator with two eccentric motors working at different frequencies. In both experiments, the generated wavefield was recorded in a borehole using a fiber-optic distributed acoustic sensing cable. Both experiments showed combinational frequencies, harmonics, and other intermodulation products of the fundamental frequencies both on the surface and at depth. Laboratory experiments replicated the setup of the field test with vibroseis sources and showed similar nonlinear combinations of fundamental frequencies. Amplitudes of the nonlinear signals observed in the laboratory showed variation with the saturating fluid. These results confirm that nonlinear components of the wavefield propagate as body waves, are likely to generate within rock formations, and can be potentially used for reservoir fluid characterization.
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Sonoluminescence and sonochemiluminescence from a microreactor.
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Micromachined pits on a substrate can be used to nucleate and stabilize microbubbles in a liquid exposed to an ultrasonic field. Under suitable conditions, the collapse of these bubbles can result in light emission (sonoluminescence, SL). Hydroxyl radicals (OH()) generated during bubble collapse can react with luminol to produce light (sonochemiluminescence, SCL). SL and SCL intensities were recorded for several regimes related to the pressure amplitude (low and high acoustic power levels) at a given ultrasonic frequency (200kHz) for pure water, and aqueous luminol and propanol solutions. Various arrangements of pits were studied, with the number of pits ranging from no pits (comparable to a classic ultrasound reactor), to three-pits. Where there was more than one pit present, in the high pressure regime the ejected microbubbles combined into linear (two-pits) or triangular (three-pits) bubble clouds (streamers). In all situations where a pit was present on the substrate, the SL was intensified and increased with the number of pits at both low and high power levels. For imaging SL emitting regions, Argon (Ar) saturated water was used under similar conditions. SL emission from aqueous propanol solution (50mM) provided evidence of transient bubble cavitation. Solutions containing 0.1mM luminol were also used to demonstrate the radical production by attaining the SCL emission regions.
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The study of acoustic scattering by single microbubbles has the potential to offer improved signal processing techniques. A microacoustic system that employs a hydrodynamically-focused flow was used to detect radiofrequency (RF) backscatter from single microbubbles. RF data were collected using a commercial scanner. Results are presented for two agents, namely Definity (Lantheus Medical Imaging, N. Billerica, MA, USA) and biSphere (Point Biomedical Corp, San Carlos, CA, USA). The agents were insonified with amplitude-modulated pulses, and it was observed in both agents that a subpopulation of microbubbles did not produce a measurable echo from the first-half amplitude pulse, but did produce a response from the full amplitude pulse and from a subsequent half amplitude pulse. The number of microbubbles in this subpopulation was seen to increase with increasing transmit amplitude. These results do not bear out the simple theory of microbubble-pulse sequence interaction and invite a reassessment of signal processing approaches.
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Sonoluminescence and sonochemiluminescence from a microreactor.
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Micromachined pits on a substrate can be used to nucleate and stabilize microbubbles in a liquid exposed to an ultrasonic field. Under suitable conditions, the collapse of these bubbles can result in light emission (sonoluminescence, SL). Hydroxyl radicals (OH()) generated during bubble collapse can react with luminol to produce light (sonochemiluminescence, SCL). SL and SCL intensities were recorded for several regimes related to the pressure amplitude (low and high acoustic power levels) at a given ultrasonic frequency (200kHz) for pure water, and aqueous luminol and propanol solutions. Various arrangements of pits were studied, with the number of pits ranging from no pits (comparable to a classic ultrasound reactor), to three-pits. Where there was more than one pit present, in the high pressure regime the ejected microbubbles combined into linear (two-pits) or triangular (three-pits) bubble clouds (streamers). In all situations where a pit was present on the substrate, the SL was intensified and increased with the number of pits at both low and high power levels. For imaging SL emitting regions, Argon (Ar) saturated water was used under similar conditions. SL emission from aqueous propanol solution (50mM) provided evidence of transient bubble cavitation. Solutions containing 0.1mM luminol were also used to demonstrate the radical production by attaining the SCL emission regions.
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We demonstrate experimentally, for the first time, the feasibility of passively enhancing fluorescence and Raman signals from diffusely scattering media in a conventional backscattering collection geometry. The method employs transmission of the collimated excitation laser beam through a "unidirectional" dielectric mirror placed directly in front of the sample. This permits laser light that escapes from the sample surface to be reflected back into the sample where it can be more usefully employed in generating Raman and fluorescence signals. This leads to improved Raman signal, higher signal-to-noise ratio, and shorter acquisition times. Feasibility studies performed on standard pharmaceutical tablets and on sheets of Teflon, using a single enhancing element, demonstrate signal enhancement factors of 6 (fluorescence) and 3 (Raman). Potential applications of this simple device include improving quality control of pharmaceutical products, disease diagnosis of biological tissue, forensics, and security screening.
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Sonoluminescence and sonochemiluminescence from a microreactor.
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Micromachined pits on a substrate can be used to nucleate and stabilize microbubbles in a liquid exposed to an ultrasonic field. Under suitable conditions, the collapse of these bubbles can result in light emission (sonoluminescence, SL). Hydroxyl radicals (OH()) generated during bubble collapse can react with luminol to produce light (sonochemiluminescence, SCL). SL and SCL intensities were recorded for several regimes related to the pressure amplitude (low and high acoustic power levels) at a given ultrasonic frequency (200kHz) for pure water, and aqueous luminol and propanol solutions. Various arrangements of pits were studied, with the number of pits ranging from no pits (comparable to a classic ultrasound reactor), to three-pits. Where there was more than one pit present, in the high pressure regime the ejected microbubbles combined into linear (two-pits) or triangular (three-pits) bubble clouds (streamers). In all situations where a pit was present on the substrate, the SL was intensified and increased with the number of pits at both low and high power levels. For imaging SL emitting regions, Argon (Ar) saturated water was used under similar conditions. SL emission from aqueous propanol solution (50mM) provided evidence of transient bubble cavitation. Solutions containing 0.1mM luminol were also used to demonstrate the radical production by attaining the SCL emission regions.
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Passive cavitation detection can be performed to monitor microbubble activity during brain therapy. Microbubbles under ultrasound exposure generate a response characterized by multiple nonlinear emissions. Here, the wide bandwidth of capacitive micromachined ultrasonic transducers (CMUTs) was exploited to monitor the microbubble signature through a rat skull and a macaque skull. The intrinsic nonlinearity of the CMUTs was characterized in receive mode. Indeed, undesirable nonlinear components generated by the CMUTs must be minimized as they can mask the microbubble harmonic response. The microbubble signature at harmonic and ultra-harmonic components (0.5-6 MHz) was successfully extracted through a rat skull using moderate bias voltage.
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Recent divergence in the contributions of tropical and boreal forests to the terrestrial carbon sink.
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Anthropogenic land use and land cover changes (LULCC) have a large impact on the global terrestrial carbon sink, but this effect is not well characterized according to biogeographical region. Here, using state-of-the-art Earth observation data and a dynamic global vegetation model, we estimate the impact of LULCC on the contribution of biomes to the terrestrial carbon sink between 1992 and 2015. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink. CO<sub>2</sub> fertilization was found to be the main driver increasing the terrestrial carbon sink from 1992 to 2015, but the net effect of all drivers (CO<sub>2</sub> fertilization and nitrogen deposition, LULCC and meteorological forcing) caused a reduction and an increase, respectively, in the terrestrial carbon sink for tropical and boreal forests. These diverging trends were not observed when applying a conventional LULCC dataset, but were also evident in satellite passive microwave estimates of aboveground biomass. These datasets thereby converge on the conclusion that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the growing terrestrial carbon sink.
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The forest root-shoot ratio (R/S), i.e., the ratio of belowground to aboveground biomass at the stand level, is widely used in global and regional forest carbon stock estimation and in modeling of the forest carbon cycle. Despite recent advances in understanding forest R/S variations at the individual-tree level, spatial patterns of stand-level forest R/S ratio across the globe and their driving factors remain relatively unknown. Here, we compiled and analyzed an extensive dataset from 873 forest sites worldwide, analyzed and quantified the effects of major environmental and forest growth-related variables on the stand-level R/S ratio. Based on this analysis, we further mapped the spatial pattern of the global forest R/S ratio. Our results show that, globally, variations on the stand-level forest R/S ratio are largely affected by canopy height, latitude, climatic water deficit, forest type and regeneration method, which collectively explain 37% of the variations in R/S ratio. In addition, our results suggest significant intercontinental and national variations in forest R/S ratio. At the continental scale, forest R/S ratio is highest in Oceania and lowest in South America. At the national scale, Australia has the highest forest R/S ratio while Russia has the lowest values. The forest R/S ratio is generally lower in moist tropical regions, but increases when moving to the extra-tropics when seasonality in precipitation increases. The R/S ratio in temperate and boreal regions shows prominent spatial features regulated by forest species composition and regeneration method. We conclude that future changes in environmental, biotic and anthropogenic factors, such as increased climatic water deficit and forest management, might influence the forest R/S ratio, with implications for the global and regional land carbon cycle.
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Recent divergence in the contributions of tropical and boreal forests to the terrestrial carbon sink.
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Anthropogenic land use and land cover changes (LULCC) have a large impact on the global terrestrial carbon sink, but this effect is not well characterized according to biogeographical region. Here, using state-of-the-art Earth observation data and a dynamic global vegetation model, we estimate the impact of LULCC on the contribution of biomes to the terrestrial carbon sink between 1992 and 2015. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink. CO<sub>2</sub> fertilization was found to be the main driver increasing the terrestrial carbon sink from 1992 to 2015, but the net effect of all drivers (CO<sub>2</sub> fertilization and nitrogen deposition, LULCC and meteorological forcing) caused a reduction and an increase, respectively, in the terrestrial carbon sink for tropical and boreal forests. These diverging trends were not observed when applying a conventional LULCC dataset, but were also evident in satellite passive microwave estimates of aboveground biomass. These datasets thereby converge on the conclusion that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the growing terrestrial carbon sink.
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The area burned in the North American boreal forest is controlled by the frequency of mid-tropospheric blocking highs that cause rapid fuel drying. Climate controls the area burned through changing the dynamics of large-scale teleconnection patterns (Pacific Decadal Oscillation/El Niño Southern Oscillation and Arctic Oscillation, PDO/ENSO and AO) that control the frequency of blocking highs over the continent at different time scales. Changes in these teleconnections may be caused by the current global warming. Thus, an increase in temperature alone need not be associated with an increase in area burned in the North American boreal forest. Since the end of the Little Ice Age, the climate has been unusually moist and variable: large fire years have occurred in unusual years, fire frequency has decreased and fire-climate relationships have occurred at interannual to decadal time scales. Prolonged and severe droughts were common in the past and were partly associated with changes in the PDO/ENSO system. Under these conditions, large fire years become common, fire frequency increases and fire-climate relationships occur at decadal to centennial time scales. A suggested return to the drier climate regimes of the past would imply major changes in the temporal dynamics of fire-climate relationships and in area burned, a reduction in the mean age of the forest, and changes in species composition of the North American boreal forest.
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Recent divergence in the contributions of tropical and boreal forests to the terrestrial carbon sink.
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Anthropogenic land use and land cover changes (LULCC) have a large impact on the global terrestrial carbon sink, but this effect is not well characterized according to biogeographical region. Here, using state-of-the-art Earth observation data and a dynamic global vegetation model, we estimate the impact of LULCC on the contribution of biomes to the terrestrial carbon sink between 1992 and 2015. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink. CO<sub>2</sub> fertilization was found to be the main driver increasing the terrestrial carbon sink from 1992 to 2015, but the net effect of all drivers (CO<sub>2</sub> fertilization and nitrogen deposition, LULCC and meteorological forcing) caused a reduction and an increase, respectively, in the terrestrial carbon sink for tropical and boreal forests. These diverging trends were not observed when applying a conventional LULCC dataset, but were also evident in satellite passive microwave estimates of aboveground biomass. These datasets thereby converge on the conclusion that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the growing terrestrial carbon sink.
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Forest disturbances such as drought, fire, and logging affect the forest carbon dynamics and the terrestrial carbon sink. Forest mortality after disturbances creates uncertainties that need to be accounted for to understand forest dynamics and their associated C-sink. We combined data from permanent resampling plots and biomass oriented dendroecological plots to estimate time series of annual woody biomass growth (ABI) in several forests. ABI time series were used to benchmark a vegetation model to analyze dynamics in forest productivity and carbon allocation forced by environmental variability. The model implements source and sink limitations explicitly by dynamically constraining carbon allocation of assimilated photosynthates as a function of temperature and moisture. Bias in tree-ring reconstructed ABI increased back in time from data collection and with increasing disturbance intensity. ABI bias ranged from zero, in open stands without recorded mortality, to over 100% in stands with major disturbances such as thinning or snowstorms. Stand leaf area was still lower than in control plots decades after heavy thinning. Disturbances, species life-history strategy and climatic variability affected carbon-partitioning patterns in trees. Resprouting broadleaves reached maximum biomass growth at earlier ages than nonresprouting conifers. Environmental variability and leaf area explained much variability in woody biomass allocation. Effects of stand competition on C-allocation were mediated by changes in stand leaf area except after major disturbances. Divergence between tree-ring estimated and simulated ABI were caused by unaccounted changes in allocation or misrepresentation of some functional process independently of the model calibration approach. Higher disturbance intensity produced greater modifications of the C-allocation pattern, increasing error in reconstructed biomass dynamics. Legacy effects from disturbances decreased model performance and reduce the potential use of ABI as a proxy to net primary productivity. Trait-based dynamics of C-allocation in response to environmental variability need to be refined in vegetation models.
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Recent divergence in the contributions of tropical and boreal forests to the terrestrial carbon sink.
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Anthropogenic land use and land cover changes (LULCC) have a large impact on the global terrestrial carbon sink, but this effect is not well characterized according to biogeographical region. Here, using state-of-the-art Earth observation data and a dynamic global vegetation model, we estimate the impact of LULCC on the contribution of biomes to the terrestrial carbon sink between 1992 and 2015. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink. CO<sub>2</sub> fertilization was found to be the main driver increasing the terrestrial carbon sink from 1992 to 2015, but the net effect of all drivers (CO<sub>2</sub> fertilization and nitrogen deposition, LULCC and meteorological forcing) caused a reduction and an increase, respectively, in the terrestrial carbon sink for tropical and boreal forests. These diverging trends were not observed when applying a conventional LULCC dataset, but were also evident in satellite passive microwave estimates of aboveground biomass. These datasets thereby converge on the conclusion that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the growing terrestrial carbon sink.
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Tropical ecosystems are under increasing pressure from land-use change and deforestation. Changes in tropical forest cover are expected to affect carbon and water cycling with important implications for climatic stability at global scales. A major roadblock for predicting how tropical deforestation affects climate is the lack of baseline conditions (i.e., prior to human disturbance) of forest-savanna dynamics. To address this limitation, we developed a long-term analysis of forest and savanna distribution across the Amazon-Cerrado transition of central Brazil. We used soil organic carbon isotope ratios as a proxy for changes in woody vegetation cover over time in response to fluctuations in precipitation inferred from speleothem oxygen and strontium stable isotope records. Based on stable isotope signatures and radiocarbon activity of organic matter in soil profiles, we quantified the magnitude and direction of changes in forest and savanna ecosystem cover. Using changes in tree cover measured in 83 different locations for forests and savannas, we developed interpolation maps to assess the coherence of regional changes in vegetation. Our analysis reveals a broad pattern of woody vegetation expansion into savannas and densification within forests and savannas for at least the past ~1,600 years. The rates of vegetation change varied significantly among sampling locations possibly due to variation in local environmental factors that constrain primary productivity. The few instances in which tree cover declined (7.7% of all sampled profiles) were associated with savannas under dry conditions. Our results suggest a regional increase in moisture and expansion of woody vegetation prior to modern deforestation, which could help inform conservation and management efforts for climate change mitigation. We discuss the possible mechanisms driving forest expansion and densification of savannas directly (i.e., increasing precipitation) and indirectly (e.g., decreasing disturbance) and suggest future research directions that have the potential to improve climate and ecosystem models.
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Recent divergence in the contributions of tropical and boreal forests to the terrestrial carbon sink.
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Anthropogenic land use and land cover changes (LULCC) have a large impact on the global terrestrial carbon sink, but this effect is not well characterized according to biogeographical region. Here, using state-of-the-art Earth observation data and a dynamic global vegetation model, we estimate the impact of LULCC on the contribution of biomes to the terrestrial carbon sink between 1992 and 2015. Tropical and boreal forests contributed equally, and with the largest share of the mean global terrestrial carbon sink. CO<sub>2</sub> fertilization was found to be the main driver increasing the terrestrial carbon sink from 1992 to 2015, but the net effect of all drivers (CO<sub>2</sub> fertilization and nitrogen deposition, LULCC and meteorological forcing) caused a reduction and an increase, respectively, in the terrestrial carbon sink for tropical and boreal forests. These diverging trends were not observed when applying a conventional LULCC dataset, but were also evident in satellite passive microwave estimates of aboveground biomass. These datasets thereby converge on the conclusion that LULCC have had a greater impact on tropical forests than previously estimated, causing an increase and decrease of the contributions of boreal and tropical forests, respectively, to the growing terrestrial carbon sink.
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Wildfires strongly regulate carbon (C) cycling and storage in boreal forests and account for almost 10% of global fire C emissions. However, the anticipated effects of climate change on fire regimes may destabilize current C-climate feedbacks and switch the systems to new stability domains. Since most of these forests are located in upland soils where permafrost is widespread, the expected climate warming and drying combined with more active fires may alter the greenhouse gas (GHG) budgets of boreal forests and trigger unprecedented changes in the global C balance. Therefore, a better understanding of the effects of fires on the various spatial and temporal patterns of GHG fluxes of different physical environments (permafrost and nonpermafrost soils) is fundamental to an understanding of the role played by fire in future climate feedbacks. While large amounts of C are released during fires, postfire GHG fluxes play an important role in boreal C budgets over the short and long term. The timescale over which the vegetation cover regenerates seems to drive the recovery of C emissions after both low- and high-severity fires, regardless of fire-induced changes in soil decomposition. In soils underlain by permafrost, fires increase the active layer depth for several years, which may alter the soil dynamics regulating soil GHG exchange. In a scenario of global warming, prolonged exposition of previously immobilized C could result in higher carbon dioxide emission during the early fire succession. However, without knowledge of the contribution of each respiration component combined with assessment of the warming and drying effects on both labile and recalcitrant soil organic matter throughout the soil profile, we cannot advance on the most relevant feedbacks involving fire and permafrost. Fires seem to have either negligible effects on methane (CH<sub>4</sub>) fluxes or a slight increase in CH<sub>4</sub> uptake. However, permafrost thawing driven by climate or fire could turn upland boreal soils into temporary CH<sub>4</sub> sources, depending on how fast the transition from moist to drier soils occurs. Most studies indicate a slight decrease or no significant change in postfire nitrous oxide (N<sub>2</sub>O) fluxes. However, simulations have shown that the temperature sensitivity of denitrification exceeds that of soil respiration; thus, the effects of warming on soil N<sub>2</sub>O emissions may be greater than on C emissions.
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Influence of activation modes on diametral tensile strength of dual-curing resin cements.
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In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).
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This study is aimed at evaluating the flexural strength (FS), fracture toughness (FT), and diametral tensile strength (DTS) of three resin-modified glass-ionomer cements (RMGICs): Ketac Nano, Riva Light Cure, and Fuji II LC. One hundred twenty specimens were prepared from the RMGIC materials (<i>n</i> = 10). The cements were mixed and inserted into different mould sizes according to the test performed: FS: rectangular Teflon mould (32 mm × 3.15 mm × 2 mm); FT: notchless triangular prism (NTP) Teflon mould (6 mm × 6 mm × 6 mm × 12 mm); and DTS: ring road stainless steel mould (6 mm × 3 mm). Specimens were light cured for 20 seconds on each surface and stored in distilled water at 37°C ± 2°C for seven days prior to tests. To evaluate the influence of storage in the mechanical properties of the RMGIs, specimens tested for DTS were stored in distilled water at 37°C ± 2°C for 32 days prior to test. Data were analyzed by ANOVA and Tukey's test (<i>α</i> = 0.05). Fuji II LC presented significantly higher values for all tests employed when compared to Ketac Nano and Riva LC RMGIs. There was no significant difference on DTS before and after the 32-day storage for each material. Fuji II LC presented superior mechanical properties when compared to Ketac Nano, and Riva LC storage showed no influence on the mechanical properties of the RMGI materials tested.
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Influence of activation modes on diametral tensile strength of dual-curing resin cements.
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In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).
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This study evaluated the degree of conversion, the free radical entrapment, and the chemical interaction of self-adhesive resin cements mixed with pure hydroxyapatite, as a function of the polymerization activation mode among a variety of commercial self-adhesive cements.
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Influence of activation modes on diametral tensile strength of dual-curing resin cements.
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In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).
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This study evaluated the effect of C-factor on the bond strength of a resin composite to floor and wall dentin using various adhesive systems.
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Influence of activation modes on diametral tensile strength of dual-curing resin cements.
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In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).
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To assess the effect of different surface pretreatments on the shear bond strength of resin luting material on CAD-CAM composite resins and a polymer-infiltrated ceramic network (PICN).
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Influence of activation modes on diametral tensile strength of dual-curing resin cements.
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In metallic restorations, the polymerization of dual-curing resin cements depends exclusively on chemical activation. The effect of the lack of photoactivation on the strength of these cements has been rarely studied. This study evaluated the influence of activation modes on the diametral tensile strength (DTS) of dual-curing resin cements. Base and catalyst pastes of Panavia F, Variolink II, Scotchbond Resin Cement, Rely X and Enforce were mixed and inserted into cylindrical metal moulds (4 x 2 mm). Cements were either: 1) not exposed to light (chemical activation = self-cured groups) or 2) photoactivated through mylar strips (chemical and photo-activation = dual-cured groups) (n = 10). After a 24 h storage in 37 masculineC distilled water, specimens were subjected to compressive load in a testing machine. A self-curing resin cement (Cement-It) and a zinc phosphate cement served as controls. Comparative analyses were performed: 1) between the activation modes for each dual-curing resin cement, using Students t test; 2) among the self-cured groups of the dual-curing resin cements and the control groups, using one-way ANOVA and Tukeys test (alpha = 0.05). The dual-cured groups of Scotchbond Resin Cement (53.3 MPa), Variolink II (48.4 MPa) and Rely X (51.6 MPa) showed higher DTS than that of self-cured groups (44.6, 40.4 and 44.5 MPa respectively) (p < 0.05). For Enforce (48.5 and 47.8 MPa) and Panavia F (44.0 and 43.3 MPa), no significant difference was found between the activation modes (p > 0.05). The self-cured groups of all the dual-curing resin cements presented statistically the same DTS as that of Cement-It (44.1 MPa) (p > 0.05), and higher DTS than that of zinc phosphate (4.2 MPa). Scotchbond Resin Cement, Variolink II and Rely X depended on photoactivation to achieve maximum DTS. In the absence of light, all the dual-curing resin cements presented higher DTS than that of zinc phosphate and statistically the same as that of Cement-It (p > 0.05).
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This study investigated potential variations in polymerisation of light- and dual-cured (LC and DC) resin cements photoactivated through four CAD/CAM restorative materials as a function of substrate thickness.
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Etomidate is still a valid anesthetic for electroconvulsive therapy.
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Komatsu et al have recently written that the use of etomidate as an anesthetic induction agent for surgery is associated with increased 30-day mortality and cardiovascular morbidity, compared with propofol. Etomidate has long been recognized as suppressing adrenocortical function and, as an infusion over days, has been indicted in increasing intensive care unit patient mortality. Even in single doses, etomidate causes a reduction in cortisol production, although recovery from single-dose suppression is generally prompt. In prospectively evaluating etomidate as an anesthetic for electroconvulsive therapy, Lebowitz et al, in a pilot study, found that 3 times per week, etomidate did not cause adrenocortical suppression that lasted until the following treatment. The steroid responses did not differ from those of methohexital, and no patient demonstrated evidence of cortisol deficiency. Consequently, concerns raised by Komatsu et al about etomidate's safety seem unwarranted when used for electroconvulsive therapy, and their study's conclusions likely relate to issues with their retrospective methodology.
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To report a case of etomidate induced seizure in a patient that received 0.15 mg/kg of etomidate for a procedural sedation which resolved without intervention.
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Etomidate is still a valid anesthetic for electroconvulsive therapy.
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Komatsu et al have recently written that the use of etomidate as an anesthetic induction agent for surgery is associated with increased 30-day mortality and cardiovascular morbidity, compared with propofol. Etomidate has long been recognized as suppressing adrenocortical function and, as an infusion over days, has been indicted in increasing intensive care unit patient mortality. Even in single doses, etomidate causes a reduction in cortisol production, although recovery from single-dose suppression is generally prompt. In prospectively evaluating etomidate as an anesthetic for electroconvulsive therapy, Lebowitz et al, in a pilot study, found that 3 times per week, etomidate did not cause adrenocortical suppression that lasted until the following treatment. The steroid responses did not differ from those of methohexital, and no patient demonstrated evidence of cortisol deficiency. Consequently, concerns raised by Komatsu et al about etomidate's safety seem unwarranted when used for electroconvulsive therapy, and their study's conclusions likely relate to issues with their retrospective methodology.
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To investigate the clinical efficacy of modified electroconvulsive therapy (MECT) in patients with schizophrenia and provide a reference for the selection of safe and effective treatment options in clinical practice.
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Etomidate is still a valid anesthetic for electroconvulsive therapy.
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Komatsu et al have recently written that the use of etomidate as an anesthetic induction agent for surgery is associated with increased 30-day mortality and cardiovascular morbidity, compared with propofol. Etomidate has long been recognized as suppressing adrenocortical function and, as an infusion over days, has been indicted in increasing intensive care unit patient mortality. Even in single doses, etomidate causes a reduction in cortisol production, although recovery from single-dose suppression is generally prompt. In prospectively evaluating etomidate as an anesthetic for electroconvulsive therapy, Lebowitz et al, in a pilot study, found that 3 times per week, etomidate did not cause adrenocortical suppression that lasted until the following treatment. The steroid responses did not differ from those of methohexital, and no patient demonstrated evidence of cortisol deficiency. Consequently, concerns raised by Komatsu et al about etomidate's safety seem unwarranted when used for electroconvulsive therapy, and their study's conclusions likely relate to issues with their retrospective methodology.
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Electroconvulsive therapy (ECT) is a therapeutic procedure in many mood and psychiatric disorders. After induction of general anesthesia by administering an induction dose of an intravenous anesthetic such as Propofol, intravenous succinylcholine is often used to prevent bone fractures and joint dislocations during ECT. Intraocular pressure (IOP) is raised by succinylcholine and tonic-colonic convulsion,and decreased by propofol administration. To our knowledge, there is no published paper on the effect of ECT using propofol and succinylcholine on the IOP. This study for the first time shows the effect of ECT on IOP. The source of the financial support is a grant allocation of Zahedan University of Medical Sciences. There is no financial relationship between authors and commercial interest with a vested interest in the outcome of the study.
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Etomidate is still a valid anesthetic for electroconvulsive therapy.
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Komatsu et al have recently written that the use of etomidate as an anesthetic induction agent for surgery is associated with increased 30-day mortality and cardiovascular morbidity, compared with propofol. Etomidate has long been recognized as suppressing adrenocortical function and, as an infusion over days, has been indicted in increasing intensive care unit patient mortality. Even in single doses, etomidate causes a reduction in cortisol production, although recovery from single-dose suppression is generally prompt. In prospectively evaluating etomidate as an anesthetic for electroconvulsive therapy, Lebowitz et al, in a pilot study, found that 3 times per week, etomidate did not cause adrenocortical suppression that lasted until the following treatment. The steroid responses did not differ from those of methohexital, and no patient demonstrated evidence of cortisol deficiency. Consequently, concerns raised by Komatsu et al about etomidate's safety seem unwarranted when used for electroconvulsive therapy, and their study's conclusions likely relate to issues with their retrospective methodology.
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Nowadays, electroconvulsive therapy (ECT) is undergoing a renaissance in psychiatry: it is now considered a first-line therapy for treating psychotic depression or other disorders with severe depressive symptoms. Surprisingly, ECT is most commonly not used as continuation therapy after acute remission. With rare exceptions, antidepressive medication is chosen for this purpose. The use of continuation ECT (cECT) and subsequent maintenance ECT (mECT) is not or just marginally mentioned in practice guidelines. In this article, we suggest guidelines for cECT, taking therapy recommendations and recent studies into account. Particularly, indication, management, comedication and comorbidity, side effects, and costs are examined. Today, cECT is underindicated as a result of assumed problems, fears, and stigmas. We would therefore recommend broader use of this proven treatment tool for keeping major depression in remission.
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Etomidate is still a valid anesthetic for electroconvulsive therapy.
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Komatsu et al have recently written that the use of etomidate as an anesthetic induction agent for surgery is associated with increased 30-day mortality and cardiovascular morbidity, compared with propofol. Etomidate has long been recognized as suppressing adrenocortical function and, as an infusion over days, has been indicted in increasing intensive care unit patient mortality. Even in single doses, etomidate causes a reduction in cortisol production, although recovery from single-dose suppression is generally prompt. In prospectively evaluating etomidate as an anesthetic for electroconvulsive therapy, Lebowitz et al, in a pilot study, found that 3 times per week, etomidate did not cause adrenocortical suppression that lasted until the following treatment. The steroid responses did not differ from those of methohexital, and no patient demonstrated evidence of cortisol deficiency. Consequently, concerns raised by Komatsu et al about etomidate's safety seem unwarranted when used for electroconvulsive therapy, and their study's conclusions likely relate to issues with their retrospective methodology.
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Electroconvulsive therapy (ECT) is widely used for treatment-resistant depression. However, it is unclear whether/how ECT can be targeted to affect brain regions and circuits in the brain to dynamically regulate mood and cognition.
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Memorialization Practices Are Changing: An Industry Perspective on Improving Service Outcomes for the Bereaved.
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Although considerable research efforts have focused on bereavement outcomes following loss, there are few studies which address the role of memorialization, particularly as it relates to formal service provision. Currently the funeral, cemetery, and crematorium industries are observing a steady decline in traditional and formal memorialization practices. This study aims to identify current memorialization practices and emerging trends, highlight key priorities for improving service outcomes for the bereaved, and understand the implications of changing consumer preferences for service provision. The study's qualitative research design incorporates two phases, a scoping literature review followed by in-depth interviews with eight service providers from the funeral, cemetery, and crematorium industries. A key finding is that the trend toward contemporary and informal memorialization practices blurs the lines between the role of consumers and service providers. There is a clear opportunity for service providers to engage in community education as a means of building supportive relationships with and improving service outcomes for the bereaved.
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Evolving financial and medical constraints fueled by the increasing repertoire of nonoperating room cases and widening scope of patient comorbidities are discussed. The need to integrate finances and care approaches is detailed, and strategic suggestions for broader collaborative practice are suggested.
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Memorialization Practices Are Changing: An Industry Perspective on Improving Service Outcomes for the Bereaved.
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Although considerable research efforts have focused on bereavement outcomes following loss, there are few studies which address the role of memorialization, particularly as it relates to formal service provision. Currently the funeral, cemetery, and crematorium industries are observing a steady decline in traditional and formal memorialization practices. This study aims to identify current memorialization practices and emerging trends, highlight key priorities for improving service outcomes for the bereaved, and understand the implications of changing consumer preferences for service provision. The study's qualitative research design incorporates two phases, a scoping literature review followed by in-depth interviews with eight service providers from the funeral, cemetery, and crematorium industries. A key finding is that the trend toward contemporary and informal memorialization practices blurs the lines between the role of consumers and service providers. There is a clear opportunity for service providers to engage in community education as a means of building supportive relationships with and improving service outcomes for the bereaved.
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Moving away from a physician-centric model of care is difficult, but the quality and cost benefits may be worth it.
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Memorialization Practices Are Changing: An Industry Perspective on Improving Service Outcomes for the Bereaved.
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Although considerable research efforts have focused on bereavement outcomes following loss, there are few studies which address the role of memorialization, particularly as it relates to formal service provision. Currently the funeral, cemetery, and crematorium industries are observing a steady decline in traditional and formal memorialization practices. This study aims to identify current memorialization practices and emerging trends, highlight key priorities for improving service outcomes for the bereaved, and understand the implications of changing consumer preferences for service provision. The study's qualitative research design incorporates two phases, a scoping literature review followed by in-depth interviews with eight service providers from the funeral, cemetery, and crematorium industries. A key finding is that the trend toward contemporary and informal memorialization practices blurs the lines between the role of consumers and service providers. There is a clear opportunity for service providers to engage in community education as a means of building supportive relationships with and improving service outcomes for the bereaved.
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Home health company Gentiva Health Services' proposed purchase of hospice provider Odyssey HealthCare highlights the growing movement of for-profit companies into the hospice sector. The deal is a "perfect marriage" for both, says Donald Schumacher, left, of the National Hospice and Palliative Care Organization. "It is a part of what we'll be seeing in our industry more and more--organizations joining forces as they build their footprint in the home health and hospice world".
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Memorialization Practices Are Changing: An Industry Perspective on Improving Service Outcomes for the Bereaved.
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Although considerable research efforts have focused on bereavement outcomes following loss, there are few studies which address the role of memorialization, particularly as it relates to formal service provision. Currently the funeral, cemetery, and crematorium industries are observing a steady decline in traditional and formal memorialization practices. This study aims to identify current memorialization practices and emerging trends, highlight key priorities for improving service outcomes for the bereaved, and understand the implications of changing consumer preferences for service provision. The study's qualitative research design incorporates two phases, a scoping literature review followed by in-depth interviews with eight service providers from the funeral, cemetery, and crematorium industries. A key finding is that the trend toward contemporary and informal memorialization practices blurs the lines between the role of consumers and service providers. There is a clear opportunity for service providers to engage in community education as a means of building supportive relationships with and improving service outcomes for the bereaved.
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Healthcare organizations can improve their year-end malpractice insurance accruals by taking the following steps: Maintain productive communication. Match accrual and accounting policies. Adjust amount of credit to own historical loss experience. Request more frequent analysis. Obtain a second opinion.
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Memorialization Practices Are Changing: An Industry Perspective on Improving Service Outcomes for the Bereaved.
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Although considerable research efforts have focused on bereavement outcomes following loss, there are few studies which address the role of memorialization, particularly as it relates to formal service provision. Currently the funeral, cemetery, and crematorium industries are observing a steady decline in traditional and formal memorialization practices. This study aims to identify current memorialization practices and emerging trends, highlight key priorities for improving service outcomes for the bereaved, and understand the implications of changing consumer preferences for service provision. The study's qualitative research design incorporates two phases, a scoping literature review followed by in-depth interviews with eight service providers from the funeral, cemetery, and crematorium industries. A key finding is that the trend toward contemporary and informal memorialization practices blurs the lines between the role of consumers and service providers. There is a clear opportunity for service providers to engage in community education as a means of building supportive relationships with and improving service outcomes for the bereaved.
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Understanding experiences with private important to improving the quality of health care coverage.
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The relevance of music therapy in paediatric and adolescent cancer patients: a scoping review.
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Music therapy is an emerging and useful methodology to improve the quality of life of children and adolescents with cancer.
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Scoping review.
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The relevance of music therapy in paediatric and adolescent cancer patients: a scoping review.
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Music therapy is an emerging and useful methodology to improve the quality of life of children and adolescents with cancer.
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Patients with cancer frequently experience difficulties with everyday activities. This scoping review explores occupational therapy group interventions in oncology, an area relevant to occupational therapy practitioners, but one that has limited evidence.
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The relevance of music therapy in paediatric and adolescent cancer patients: a scoping review.
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Music therapy is an emerging and useful methodology to improve the quality of life of children and adolescents with cancer.
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To present scientific evidence, based on a systematic review of the literature, on the benefit of brainstem implants in auditory rehabilitation and language development in children.
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The relevance of music therapy in paediatric and adolescent cancer patients: a scoping review.
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Music therapy is an emerging and useful methodology to improve the quality of life of children and adolescents with cancer.
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This systematic review and meta-analysis examined the effects of psychological therapies for management of chronic pain in children.
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The relevance of music therapy in paediatric and adolescent cancer patients: a scoping review.
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Music therapy is an emerging and useful methodology to improve the quality of life of children and adolescents with cancer.
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In childhood intervention, parent-therapist collaboration is central to the family-centred approach. Despite long-standing discussion in occupational therapy literature, the field faces challenges, including inconsistent terminology and difficulties in translating theory into practice. This paper represents the first part of a comprehensive scoping review study aimed at developing foundational concepts for collaborative practices with parents in occupational therapy for children. Therefore, this paper focusses on mapping existing practices, types, and approaches articulated in the literature.
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Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments.
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Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52.
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Loss of response (LOR) to infliximab (IFX) remains a challenge in the management of inflammatory bowel diseases (IBD). Proactive dosing strategies to achieve and maintain predefined IFX trough levels (TL) may prevent LOR. We aimed to investigate the efficacy of dashboard driven IFX dosing compared to standard dosing in a prospective trial in IBD patients.
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Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments.
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Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52.
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Therapy for Crohn's disease has long been based on a step-up approach, with monoclonal antibodies against TNF as a final option before surgery. Despite the introduction of these monoclonal antibodies, no major changes have occurred in the natural history of Crohn's disease, with half of all patients still requiring intestinal resection at 10 years. Labelling for anti-TNF agents does not take into account prognostic factors. In this Review, we propose that treatment of Crohn's disease be based on the following three disease stages: mild, moderate and severe. In patients with Crohn's disease who have complicated disease or bowel damage, and with poor prognostic factors and/or severe disease, anti-TNF treatment should be considered as first-line therapy. For patients living in areas of high risk of developing tuberculosis, as well as for patients with mild-to-moderate Crohn's disease without poor prognostic factors and with uncomplicated disease, steroids and thiopurine should be the first-line therapy. By treating patients with Crohn's disease in accordance with these disease stages, we might be able to alter disease course and reduce overtreatment. Upcoming disease-modification trials are expected to provide information to guide decision-making, ultimately changing the course of disease and improving patient quality of life.
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Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments.
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Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52.
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Routine therapeutic drug monitoring (TDM) during treatment with anti-tumour necrosis factor (anti-TNF) agents in inflammatory bowel disease may increase treatment efficacy and cost-effectiveness, and reduce the risk of loss of response.
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Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments.
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Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52.
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All patients with inflammatory bowel disease (IBD) share common therapeutic goals, such as complete mucosal healing and improved long-term outcomes (e.g., reduction in hospitalization, surgery and mortality). However, because IBD patients have diverse features in terms of severity, phenotypes, clinical courses and responses to therapy, therapeutic options for achieving these goals differ among patients, from no therapy to early introduction of combination therapy with anti-TNF and immunosuppressive agents.
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Serum Immune Profiling in Paediatric Crohn's Disease Demonstrates Stronger Immune Modulation With First-Line Infliximab Than Conventional Therapy and Pre-Treatment Profiles Predict Clinical Response to Both Treatments.
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Despite its efficacy, rational guidance for starting/stopping first-line biologic treatment in individual paediatric Crohn's disease [CD] patients is needed. We assessed how serum immune profiles before and after first-line infliximab [FL-IFX] or conventional [CONV] induction therapy associate with disease remission at week 52.
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We assessed the effectiveness of switching from intravenous to subcutaneous infliximab in patients with inflammatory bowel diseases (IBDs) treated with or without intensified intravenous regimen.
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Enantioselective Alkylation of 2-Oxindoles Catalyzed by a Bifunctional Phase-Transfer Catalyst: Synthesis of (-)-Debromoflustramine B.
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A new bifunctional phase-transfer catalyst that employs hydrogen bonding as a control element was developed to promote efficient enantioselective S<sub>N</sub> 2 reactions for the construction all-carbon quaternary stereocenters in high yield and excellent enantioselectivity (up to 97 % ee) utilizing the alkylation of a malleable oxindole substrate. The utility of the methodology was demonstrated through a concise and highly enantioselective synthesis of (-)-debromoflustramine B.
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Spirotropanyl oxindole alkaloids like alstonisine and chitosenine show a wide range of bioactivites. We report the first enantioselective synthesis of the spirotropanyl oxindole scaffold by means of a bimetallic relay catalysis strategy. A new class of E-oximino α-diazo ketones was developed for the intramolecular generation of transient azomethine ylides catalyzed by an achiral Rh<sup>II</sup> complex and a subsequent intermolecular 1,3-dipolar cycloaddition catalyzed by a chiral N,N'-dioxide Nd<sup>III</sup> Lewis acid complex. The enantioselectively catalyzed transformation has broad scope and yields the desired spirotropanyl oxindole cycloadducts in high yields and with very high enantio- and diastereoselectivity.
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Enantioselective Alkylation of 2-Oxindoles Catalyzed by a Bifunctional Phase-Transfer Catalyst: Synthesis of (-)-Debromoflustramine B.
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A new bifunctional phase-transfer catalyst that employs hydrogen bonding as a control element was developed to promote efficient enantioselective S<sub>N</sub> 2 reactions for the construction all-carbon quaternary stereocenters in high yield and excellent enantioselectivity (up to 97 % ee) utilizing the alkylation of a malleable oxindole substrate. The utility of the methodology was demonstrated through a concise and highly enantioselective synthesis of (-)-debromoflustramine B.
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The straightforward synthesis of a series of enantiomerically pure Lewis basic amides by simple condensation of commercially available enantiopure diamines with picolinic acid is reported. These compounds were shown to promote the enantioselective reduction of ketoimines with trichlorosilane. Working with the model substrate N-phenyl benzophenone imine, the new organocatalysts led to the formation of the corresponding amine, with excellent chemical efficiency (up to 99% chemical yield) and good stereoselectivity (up to 73% ee). Up to 83% of enantioselectivity was reached in the reduction of differently substituted imines.
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Enantioselective Alkylation of 2-Oxindoles Catalyzed by a Bifunctional Phase-Transfer Catalyst: Synthesis of (-)-Debromoflustramine B.
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A new bifunctional phase-transfer catalyst that employs hydrogen bonding as a control element was developed to promote efficient enantioselective S<sub>N</sub> 2 reactions for the construction all-carbon quaternary stereocenters in high yield and excellent enantioselectivity (up to 97 % ee) utilizing the alkylation of a malleable oxindole substrate. The utility of the methodology was demonstrated through a concise and highly enantioselective synthesis of (-)-debromoflustramine B.
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An enantioselective isomerization of 4-iminocrotonates catalyzed by a rhodium(I)/phosphoramidite complex is described. This reaction uses widely available amines to couple with 4-oxocrotonate to provide a convenient access to a central chiral building block in good yield and high enantioselectivity. Although the mechanism of this new transformation remains unclear, both Rh and the phosphoramidite play a central role.
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Enantioselective Alkylation of 2-Oxindoles Catalyzed by a Bifunctional Phase-Transfer Catalyst: Synthesis of (-)-Debromoflustramine B.
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A new bifunctional phase-transfer catalyst that employs hydrogen bonding as a control element was developed to promote efficient enantioselective S<sub>N</sub> 2 reactions for the construction all-carbon quaternary stereocenters in high yield and excellent enantioselectivity (up to 97 % ee) utilizing the alkylation of a malleable oxindole substrate. The utility of the methodology was demonstrated through a concise and highly enantioselective synthesis of (-)-debromoflustramine B.
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The first highly enantioselective Brønsted acid catalyzed intramolecular hydroamination of alkenes enables the efficient construction of a series of chiral (spirocyclic) pyrrolidines with an α-tetrasubstituted carbon stereocenter with excellent functional group tolerance. A unique feature of this strategy is the use of a thiourea group acting as both the activating and the directing group through cooperative multiple hydrogen bonding with a Brønsted acid and the double bond. The utility of this method is highlighted by the facile construction of chiral synthetic intermediates and important structural motifs that are widely found in organic synthesis.
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Enantioselective Alkylation of 2-Oxindoles Catalyzed by a Bifunctional Phase-Transfer Catalyst: Synthesis of (-)-Debromoflustramine B.
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A new bifunctional phase-transfer catalyst that employs hydrogen bonding as a control element was developed to promote efficient enantioselective S<sub>N</sub> 2 reactions for the construction all-carbon quaternary stereocenters in high yield and excellent enantioselectivity (up to 97 % ee) utilizing the alkylation of a malleable oxindole substrate. The utility of the methodology was demonstrated through a concise and highly enantioselective synthesis of (-)-debromoflustramine B.
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We report a Rh-catalyst for accessing olefins from primary alcohols by a C-C bond cleavage that results in dehomologation. This functional group interconversion proceeds by an oxidation-dehydroformylation enabled by N, N-dimethylacrylamide as a sacrificial acceptor of hydrogen gas. Alcohols with diverse functionality and structure undergo oxidative dehydroxymethylation to access the corresponding olefins. Our catalyst protocol enables a two-step semisynthesis of (+)-yohimbenone and dehomologation of feedstock olefins.
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