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Management of portopulmonary hypertension:New perspectives

World Journal of Gastroenterology 2013年第45期19卷 8252-8257页

作者： Luigi Mancuso Francesca Scordato Michela Pieri Eliana Valerio Andrea Mancuso Department of Cardiologia Ospedale Cervello90100 Palermo Italy Cardiologia Clinica Candela 90100 Palermo Italy Epatologia e Gastroenterologia Ospedale Niguarda Cà Granda Milano 20162 Milano Italy Medicina Interna 1 ARNAS Civico 90100 Palermo Italy

Portopulmonary hypertension(PPHTN)is a known complication of cirrhosis.Moderate-to-severe PPHTN implies an extremely poor prognosis.It occurs in 5%-10%of patients referred for liver transplantation(LT),and probably with an higher incidence in patients with large portosystemic shunts.Patients with moderate-tosevere pulmonary hypertension have been previously excluded from LT because of the extremely high surgical risk and since the post-transplant outcome reported was poor.Recently,new perspectives in the management of patients with portopulmonary hypertension are emerging.In fact,some pulmonary vasoactive drugs have become routine in the treatment of patients with idiopathic pulmonary hypertension.These drugs,particularly epoprostenol,have been recently introduced in the treatment of patients with PPHTN,and have been shown to be effective in reducing pulmonary artery pressure as well as pulmonary vascular resistances.Furthermore,recent studies seem to demonstrate that treatment with pulmonary vasoactive drugs could allow liver transplantation with acceptable surgical risks and excellent survival.Although there are not large series nor prospective studies addressing this topic,the clinical scenario of patients with PPHTN seems to be positively changing.

关键词： Portopulmonary hypertension Cirrhosis Liver transplantation Management Epoprostenol

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Geographic variation in sexual selection and implications for speciation in the Barn Swallow

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Chinese Birds 2015年第1期5卷 30-42页

作者： Elizabeth SC scordato Rebecca J Safran Department of Ecology and Evolutionary Biology The University of Colorado

Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.

关键词： Barn Swallow Geographic variation Natural selection Sexual selection Speciation Tail streamers Ventral color

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A robust new metric of phenotypic distance to estimate and compare multiple trait differences among populations

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Current Zoology 2012年第3期58卷 426-439页

作者： Rebecca SAFRAN Samuel FLAXMAN Michael KOPP Darren E. IRWIN Derek BRIGGS Matthew R. EVANS W. Chris FUNK David A. GRAY Eileen A. HEBETS Nathalie SEDDON Elizabeth scordato Laurel B. SYMES Joseph A. TOBIAS David P. L. TOEWS J. Albert C. UY Department of Ecology and Evolutionary Biology University of Colorado Boulder CO 80309 U.S.A. Mathematics and B iosciences Group Faculty of Mathematics University of Vienna A-1090 Vienna Austria Current address Evolutionary Biology and Modeling Group Faculty of Sciences Aix-Marseille University 13331 Marseille France. Department of Zoology University of British Columbia 6270 University Boulevard Vancouver BC Canada V6T 1Z4. Research ＆ Evaluation Methodology School of Education University of Colorado Boulder CO 80309 U.S.A. School of Biological and Chemical Sciences Queen Mary University of London London E1 4NS Department of Biology Colorado State University Fort Collins CO 80523 U.S.A. Department of Biology California State University Northridge CA 91330 U.S.A. School of Biological Sciences University of Nebraska Lincoln NE 68588 U.S.A. Edward Grey Institute Department of Zoology University of Oxford Oxford OX1 3PS UK Committee on Evolutionary Biology The University of Chicago Chicago IL 60637U.S.A. Department of Biology Dartmouth College Hanover NH 03755 U.S.A. Department of Biology University of Miami Coral Gables FL 33146 U.S.A.

Whereas a rich literature exists for estimating population genetic divergence, metrics of phenotypic trait divergence are lacking, particularly for comparing multiple traits among three or more populations. Here, we review and analyze via simulation Hedges’ g, a widely used parametric estimate of effect size. Our analyses indicate that g is sensitive to a combination of unequal trait variances and unequal sample sizes among populations and to changes in the scale of measurement. We then go on to derive and explain a new, non-parametric distance measure, "Δp", which is calculated based upon a joint cumulative distribution function (CDF) from all populations under study. More precisely, distances are measured in terms of the percentiles in this CDF at which each population’s median lies. Δp combines many desirable features of other distance metrics into a single metric; namely, compared to other metrics, p is relatively insensitive to unequal variances and sample sizes among the populations sampled. Furthermore, a key feature of Δp—-and our main motivation for developing it—-is that it easily accommodates simultaneous comparisons of any number of traits across any number of populations. To exemplify its utility, we employ Δp to address a ques- tion related to the role of sexual selection in speciation: are sexual signals more divergent than ecological traits in closely related taxa? Using traits of known function in closely related populations, we show that traits predictive of reproductive performance are, indeed, more divergent and more sexually dimorphic than traits related to ecological adaptation.

关键词：距离估计距离度量表型性状多性状群体累积分布函数样本大小生态适应性

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