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41.
Jean Yves Le Reste Patrice Nabbe Charles Rivet Charilaos Lygidakis Christa Doerr Slawomir Czachowski Heidrun Lingner Stella Argyriadou Djurdjica Lazic Radost Assenova Melida Hasaganic Miquel Angel Munoz Hans Thulesius Bernard Le Floch Jeremy Derriennic Agnieska Sowinska Harm Van Marwijk Claire Lietard Paul Van Royen 《PloS one》2015,10(1)
Background
Multimorbidity, according to the World Health Organization, exists when there are two or more chronic conditions in one patient. This definition seems inaccurate for the holistic approach to Family Medicine (FM) and long-term care. To avoid this pitfall the European General Practitioners Research Network (EGPRN) designed a comprehensive definition of multimorbidity using a systematic literature review.Objective
To translate that English definition into European languages and to validate the semantic, conceptual and cultural homogeneity of the translations for further research.Method
Forward translation of the EGPRN’s definition of multimorbidity followed by a Delphi consensus procedure assessment, a backward translation and a cultural check with all teams to ensure the homogeneity of the translations in their national context. Consensus was defined as 70% of the scores being higher than 6. Delphi rounds were repeated in each country until a consensus was reachedResults
229 European medical expert FPs participated in the study. Ten consensual translations of the EGPRN comprehensive definition of multimorbidity were achieved.Conclusion
A comprehensive definition of multimorbidity is now available in English and ten European languages for further collaborative research in FM and long-term care. 相似文献42.
Raccoons are an important vector of rabies and other pathogens. The degree to which these pathogens can spread through a raccoon population should be closely linked to association rates between individual raccoons. Most studies of raccoon sociality have found patterns consistent with low levels of social connectivity within populations, thus the likelihood of direct pathogen transmission between raccoons is theoretically low. We used proximity detecting collars and social network metrics to calculate the degree of social connectivity in an urban raccoon population for purposes of estimating potential pathogen spread. In contrast to previous assumptions, raccoon social association networks were highly connected, and all individuals were connected to one large social network during 15 out of 18 months of study. However, these metrics may overestimate the potential for a pathogen to spread through a population, as many of the social connections were based on relatively short contact periods. To more closely reflect varying probabilities of pathogen spread, we censored the raccoon social networks based on the total amount of time spent in close proximity between two individuals per month. As this time criteria for censoring the social networks increased from one to thirty minutes, corresponding measures of network connectivity declined. These findings demonstrate that raccoon populations are much more tightly connected than would have been predicted based on previous studies, but also point out that additional research is needed to calculate more precise transmission probabilities by infected individuals, and determine how disease infection changes normal social behaviors. 相似文献
43.
Massip S Guillon J Bertarelli D Bosc JJ Léger JM Lacher S Bontemps C Dupont T Müller CE Jarry C 《Bioorganic & medicinal chemistry》2006,14(8):2697-2719
The development of potent and selective adenosine receptor ligands as potential drugs is an active area of research. Xanthines are one of the most important classes of adenosine receptor antagonists and have been widely developed in terms of affinity and selectivity for adenosine receptors. We recently developed new original pathways for the synthesis of xanthine analogues starting from 5-substituted-2-amino-2-oxazoline 5 as a synthon. These procedures allowed us to selectively introduce a large, functionalized and beta-adrenergic 2-hydroxy-3-phenoxypropyl pharmacophore at the 1- and 3-position of the xanthine moiety which allowed further structural modifications. In this study, we present a new synthetic access to racemic xanthine derivatives 1-4 from 5, and their evaluation as adenosine A1, A2A and A3 receptor ligands in radioligand binding studies. The 2-hydroxy-3-phenoxypropyl moiety was well tolerated in the 3-position of the xanthine core, while its introduction in the 1-position of the xanthine moiety led to a large decrease in adenosine receptor affinity. 1,7-Dimethyl-3-[1-(2-chloro-3-phenoxypropyl)]-8-(3,4,5-trimethoxystyryl)xanthine (2n) was the most potent and selective A2A antagonist of the present series (Ki=44 nM, >200-fold selective vs A1). 1-Propyl-3-[1-(2-hydroxy-3-phenoxypropyl)]-8-noradamantylxanthine (3f) was identified as a potent (KiA1=21 nM) and highly selective (>350-fold vs A2A and A3 receptor) adenosine A1 receptor antagonist. 相似文献
44.
Conserved residues of tumour necrosis factor and lymphotoxin constitute the framework of the trimeric structure 总被引:1,自引:0,他引:1
J Tavernier X van Ostade G Hauquier T Prange I Lasters M de Maeyer A Lewit-Bentley R Fourme 《FEBS letters》1989,257(2):315-318
Four distinct areas of primary sequence conservation between known tumour necrosis factor and lymphotoxin polypeptides from various species can be recognized. When these amino acid sequences are highlighted in the three-dimensional structure, all are found in the same region, constituting the framework of the trimeric structure. 相似文献
45.
Craven C 《Medical anthropology quarterly》2005,19(2):194-215
Based on ethnographic research regarding public policy and grassroots organizing for midwifery in Virginia, this article explores how medical discourses around appropriate health care practices intersect with state discourses about what practices are considered "respectable" versus "pathological" for its citizens. In recent legislative debates about the legalization of direct-entry midwifery, medical officials have extended their criticism of midwifery and homebirth to mothers who resist state-sanctioned childbirth practices. This article examines how medical officials challenge the respectable mothering practices of homebirthers by linking them with women they deem pathological--child abusers, negligent mothers, and drug users--and placing them outside the cadre of "normal" American mothers who acknowledge the "logical" and "natural" superiority of biomedical childbirth practices. I also address homebirth mothers' responses, which assert that their political advocacy for midwives is a respectable mothering practice because they are responsible citizens who desire what they deem the best care for their children. 相似文献
46.
Christa P. H. Mulder M. Nicole Grant-Hoffman David R. Towns Peter J. Bellingham David A. Wardle Melody S. Durrett Tadashi Fukami Karen I. Bonner 《Biological invasions》2009,11(7):1671-1688
Introduced rats (Rattus spp.) can affect island vegetation structure and ecosystem functioning, both directly and indirectly (through the reduction
of seabird populations). The extent to which structure and function of islands where rats have been eradicated will converge
on uninvaded islands remains unclear. We compared three groups of islands in New Zealand: islands never invaded by rats, islands
with rats, and islands on which rats have been controlled. Differences between island groups in soil and leaf chemistry and
leaf production were largely explained by burrow densities. Community structure of woody seedlings differed by rat history
and burrow density. Plots on islands with high seabird densities had the most non-native plant species. Since most impacts
of rats were mediated through seabird density, the removal of rats without seabird recolonization is unlikely to result in
a reversal of these processes. Even if seabirds return, a novel plant community may emerge. 相似文献
47.
Carina Klein Anja Grahnert Aliaa Abdelrahman Christa E. Müller Sunna Hauschildt 《Cell calcium》2009,46(4):263-272
Extracellular nicotinamide adenine dinucleotide (NAD+) is known to increase the intracellular calcium concentration [Ca2+]i in different cell types and by various mechanisms. Here we show that NAD+ triggers a transient rise in [Ca2+]i in human monocytes activated with lipopolysaccharide (LPS), which is caused by a release of Ca2+ from IP3-responsive intracellular stores and an influx of extracellular Ca2+. By the use of P2 receptor-selective agonists and antagonists we demonstrate that P2 receptors play a role in the NAD+-induced calcium response in activated monocytes. Of the two subclasses of P2 receptors (P2X and P2Y) the P2Y receptors were considered the most likely candidates, since they share calcium signaling properties with NAD+. The identification of P2Y1 and P2Y11 as receptor subtypes responsible for the NAD+-triggered increase in [Ca2+]i was supported by several lines of evidence. First, specific P2Y1 and P2Y11 receptor antagonists inhibited the NAD+-induced increase in [Ca2+]i. Second, NAD+ was shown to potently induce calcium signals in cells transfected with either subtype, whereas untransfected cells were unresponsive. Third, NAD+ caused an increase in [cAMP]i, prevented by the P2Y11 receptor-specific antagonist NF157. 相似文献
48.
C. Betancor R. Freire A.G. Gonzalez J.A. Salazar C. Pascard T. Prange 《Phytochemistry》1980,19(9):1989-1993
The investigation of stems and leaves of Catha cassinoides afforded, in addition to sitosterol, β-amyrin, ursolic acid, lup-20(29)-en-3β,30-diol and friedelin, three new pentacyclic triterpenes: 30-hydroxyfriedelan-3-one, 29-hydroxyfriedelan-3-one and 3-oxo-friedelan-29-oic acid. The structures ofthese were determined by spectral studies and correlations, and were confirmed by X-ray analysis of 29-hydroxyfriedelan-3-one acetate. 相似文献
49.
One of the common explanations for oxidative stress in the physiological milieu is based on the Fenton reaction, i.e. the assumption that radical chain reactions are initiated by metal-catalyzed electron transfer to hydrogen peroxide yielding hydroxyl radicals. On the other hand — especially in the context of so-called “iron switches” — it is postulated that cellular signaling pathways originate from the interaction of reduced iron with hydrogen peroxide.Using fluorescence detection and EPR for identification of radical intermediates, we determined the rate of iron complexation by physiological buffer together with the reaction rate of concomitant hydroxylations of aromatic compounds under aerobic and anaerobic conditions. With the obtained overall reaction rate of 1,700 M-1s-1 for the buffer-dependent reactions and the known rates for Fenton reactions, we derive estimates for the relative reaction probabilities of both processes.As a consequence we suggest that under in vivo conditions initiation of chain reactions by hydroxyl radicals generated by the Fenton reaction is of minor importance and hence metal-dependent oxidative stress must be rather independent of the so-called “peroxide tone”. Furthermore, it is proposed that — in the low (subtoxic) concentration range — hydroxylated compounds derived from reactions of “non-free” (crypto) OH radicals are better candidates for iron-dependent sensing of redox-states and for explaining the origin of cellular signals than the generation of “free” hydroxyl radicals. 相似文献
50.
Otfried Kistner Brian A. Crowe Walter Wodal Astrid Kerschbaum Helga Savidis-Dacho Nicolas Sabarth Falko G. Falkner Ines Mayerhofer Wolfgang Mundt Manfred Reiter Leopold Grillberger Christa Tauer Michael Graninger Alois Sachslehner Michael Schwendinger Peter Brühl Thomas R. Kreil Hartmut J. Ehrlich P. Noel Barrett 《PloS one》2010,5(2)
The recent emergence and rapid spread of a novel swine-derived H1N1 influenza virus has resulted in the first influenza pandemic of this century. Monovalent vaccines have undergone preclinical and clinical development prior to initiation of mass immunization campaigns. We have carried out a series of immunogenicity and protection studies following active immunization of mice, which indicate that a whole virus, nonadjuvanted vaccine is immunogenic at low doses and protects against live virus challenge. The immunogenicity in this model was comparable to that of a whole virus H5N1 vaccine, which had previously been demonstrated to induce high levels of seroprotection in clinical studies. The efficacy of the H1N1 pandemic vaccine in protecting against live virus challenge was also seen to be equivalent to that of the H5N1 vaccine. The protective efficacy of the H1N1 vaccine was also confirmed using a severe combined immunodeficient (SCID) mouse model. It was demonstrated that mouse and guinea pig immune sera elicited following active H1N1 vaccination resulted in 100% protection of SCID mice following passive transfer of immune sera and lethal challenge. The immune responses to a whole virus pandemic H1N1 and a split seasonal H1N1 vaccine were also compared in this study. It was demonstrated that the whole virus vaccine induced a balanced Th-1 and Th-2 response in mice, whereas the split vaccine induced mainly a Th-2 response and only minimal levels of Th-1 responses. These data supported the initiation of clinical studies with the same low doses of whole virus vaccine that had previously been demonstrated to be immunogenic in clinical studies with a whole virus H5N1 vaccine. 相似文献