Bayesian species delimitation using multilocus sequence data

In the absence of recent admixture between species, bipartitions of individuals in gene trees that are shared across loci can potentially be used to infer the presence of two or more species. This approach to species delimitation via molecular sequence data has been constrained by the fact that genealogies for individual loci are often poorly resolved and that ancestral lineage sorting, hybridization, and other population genetic processes can lead to discordant gene trees. Here we use a Bayesian modeling approach to generate the posterior probabilities of species assignments taking account of uncertainties due to unknown gene trees and the ancestral coalescent process. For tractability, we rely on a user-specified guide tree to avoid integrating over all possible species delimitations. The statistical performance of the method is examined using simulations, and the method is illustrated by analyzing sequence data from rotifers, fence lizards, and human populations.     

Functional characterization of the MECP2/IRAK1 lupus risk haplotype in human T cells and a human MECP2 transgenic mouse

Genetic polymorphism in MECP2/IRAK1 on chromosome Xq28 is a confirmed and replicated susceptibility locus for lupus. High linkage disequilibrium in this locus suggests that both MECP2 and IRAK1 are candidate genes for the disease. DNA methylation changes in lupus T cells play a central role in the pathogenesis of lupus, and MeCp-2 (encoded by MECP2) is a master regulator of gene expression and is also known to recruit DNA methyltransferase 1 (DNMT1) during DNA synthesis. Using human T cells from normal individuals with either the lupus risk or the lupus protective haplotype in MECP2/IRAK1, we demonstrate that polymorphism in this locus increases MECP2 isoform 2 mRNA expression in stimulated but not unstimulated T cells. By assessing DNA methylation levels across over 485,000 methylation sites across the entire genome, we further demonstrate that the lupus risk variant in this locus is associated with significant DNA methylation changes, including in the HLA-DR and HLA-DQ loci, as well as interferon-related genes such as IFI6, IRF6, and BST2. Further, using a human MECP2 transgenic mouse, we show that overexpression of MECP2 alters gene expression in stimulated T cells. This includes overexpression of Eif2c2 that regulates the expression of multiple microRNAs (such as miR-21), and the histone demethylase Jhdm1d. In addition, we show that MECP2 transgenic mice develop antinuclear antibodies. Our data suggest that the lupus-associated variant in the MECP2/IRAK1 locus has the potential to affect all 3 epigenetic mechanisms: DNA methylation, microRNA expression, and histone modification. Importantly, these data support the notion that variants within the MECP2 gene can alter DNA methylation in other genetic loci including the HLA and interferon-regulated genes, thereby providing evidence for genetic–epigenetic interaction in lupus.     

郑州市汉族女性 MTHFR 和 MTRR 基因多态性分布

目的：探讨郑州市汉族女性5,10-亚甲基四氢叶酸还原酶(MTHFR)、甲硫氨酸合成酶还原酶(MTRR)基因 多态性的频率特征。方法：以郑州市1 253例汉族女性为研究对象,检测MTHFR C677T,A1298C和MTRR A66G的基 因分型。分析基因多态性的频率特征,并与已报道的其他地区汉族女性的数据进行比较。结果：郑州市汉族女性的 MTHFR 1298CC纯合突变基因型频率(1.3%)低于湘潭(4.8%)、延边(3.8%)、镇江(3.5%)、荆州(3.2%)、昆明(2.7%)、德 阳(6.3%)、惠州(7.2%)和乌鲁木齐(3.4%)等地(均P<0.05),等位基因与烟台、延边、乌鲁木齐、镇江、荆州、昆明、德 州、湘潭、惠州等地差异有统计学意义(均P<0.05)。MTRR 66GG纯合突变基因型频率(5.4%)低于德阳(8.2%)(P<0.01), 等位基因与德阳差异有统计学意义(P<0.05)。结论：郑州市汉族女性MTHFR A1298C和MTRR A66G基因多态性频率不 同于其他地区,具有地域特异性。     

二氢黄酮类化合物的合成研究进展

综述二氢黄酮类化合物的合成研究进展,总结已报道的各种类型的二氢黄酮合成方法,为二氢黄酮类新药研发提供方法学支持。合成方法包括:查尔酮环合、Friedel-Crafts反应、Knoevenagel缩合和Hoesch单酰基化反应,以及二氢黄酮的不对称合成,并简要介绍无溶剂合成二氢黄酮等"绿色"化学方法。     

融水小型猪的实验动物化系列研究概述

融水小型猪的种源来自广西融水县,2012年被引到广东繁育并测定了基础数据,包括种质特性、繁殖性能、生长曲线、血液学指标、血生化指标、脏器系数、染色体分析。参照国家和地方有关实验动物标准,初步建立了融水小型猪微生物与寄生虫、环境与设施、饲料、病理学、遗传学等质量控制标准。融水小型猪能适应当地气候,繁殖良好,自然受孕率为88.3%,妊娠期平均112 d,初产平均胎产仔6.1头,经产平均产仔7.9头。融水小型猪体型小,雌雄成年体重(6月龄)分别为17.21±5.20 kg和16.35±5.23 kg,性情温顺,线粒体DNA分析表明融水小型猪比兰屿猪更为古老。通过标准化的饲养管理与质量控制,具有培育成实验用小型猪的基本条件。     

PDR术后继发新生血管性青光眼围手术期血压和血糖波动性的研究

目的:研究增殖性糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)行玻璃体切除硅油取出术后继发新生血管性青光眼(neovascular glaucoma,NVG)围手术期血压、血糖的波动性.方法:回顾性分析增殖性糖尿病视网膜病变行23G玻璃体切除、联合白内障超声乳化、人工晶状体植入、硅油充填术的271例271眼,行硅油取出术后继发新生血管性青光眼的14例14眼,对照组(none neovascular glaucoma,NNVG)为随机抽取同期手术后未继发NVG的同年龄、同手术方式、排除对侧眼做对比,分析发生NVG的时间、围手术期血压、血糖变异性,随访时间为手术后1 ～ 12mo,用SPSS 11.0统计学软件分析本组新生血管性青光眼的发病率、发病时间、围手术期血糖、血压、糖化血红蛋白(Hbc％)的变异性.结果:患者271例14眼继发NVG,占5.2％;男10眼(71.4％),女4眼(28.6％);年龄49 ～ 68(平均57.07)岁;继发NVG的时间为玻璃体切除术后107 ～ 135d,硅油取出术后7 ～ 45(平均31.78)d;糖尿病史10 ～ 15(平均13.2)a.NVG组:围手术期空腹血糖波动4.0 ～10.2(平均8.52±3.24)mmol/L,变异系数0.48.NNVG组:围手术期空腹血糖波动5.0 ～8.2(平均7.22±0.24)mmol/L,变异系数0.43,两组变异系数差异有显著差异(P＜0.05).Hbc％ NVG组:(10.52±0.27)％,NNVG组:(7.60±1.34)％,两组比较差异有统计学意义(P＜0.05).NVG组:围手术期收缩压140 ～180(平均152.3±15.1)mmHg,变异系数0.099,舒张压50 ～ 110(平均92.3±11.1)mmHg,变异系数0.11;NNVG组:围手术期收缩压120 ～150(平均131.4±0.1)mmHg,变异系数0.061,舒张压80～100(平均87.3±8.1)mmHg,变异系数0.08;两组相比,变异系数有差异(P＜0.05),NVG组围手术期空腹血糖的变异性明显大于NNVG组.而两组之间昼夜血压的变异性相比,NVG组白天的收缩压(systolic blood pressure,SBP)以及夜晚的舒张压(diastolic blood pressure,DBP)的变异性均大于NNVG组,均有统计学意义(P＜0.05).14例患者取油术与玻璃体切除硅油注入手术围手术期血糖的变异性、血压的变异性相比无统计学意义.结论:PDR继发NVG患者围手术期空腹血糖的变异性、白天收缩压、夜间舒张压的变异性大,最早可发生在硅油取出术后1wk.     

农村妇女主任对当地卫生机构孕产妇保健服务的评价及其影响因素

目的:研究我国贫困农村地区妇女主任对当地不同卫生机构孕产妇保健服务(医疗设备、医务人员技术水平和态度)的满意度评价及影响其评价的相关因素。方法:自行设计问卷,采取整群分层随机调查方法,选取四川、甘肃和云南3省,14县(区),120个乡镇,993个农村的妇女主任作为调查对象,就其对当地不同卫生机构(村卫生室、乡镇卫生院、县妇幼保健站、县医院)孕产妇保健服务评价进行调查,并基于Ordered Logit模型分析影响村妇女主任评价的因素。结果:在医疗设备和医务人员技术水平方面,卫生机构的级别越高,村妇女主任对其评价越好。在医务人员态度方面,卫生机构越基层,村妇女主任对其评价越好。影响村妇女主任对不同卫生机构医疗设备、医务人员技术水平和态度评价的相关因素包括本村孕产妇保健基本情况、村妇女主任个人特征、村级社会经济情况。结论:农村妇女主任对当地不同卫生机构提供的妇幼保健服务总体较为满意,影响村妇女主任对卫生机构医疗设备、医务人员技术水平和态度评价的相关因素因卫生机构的层级而异。通过提高农村基层卫生机构孕产妇保健服务的医疗设备和技术水平、改善县级卫生机构医疗人员的服务态度、加大农村孕产妇保健服务的供给力度、重点扶持农村妇女主任开展孕产妇保健工作、强化农村妇女主任孕产妇保健知识的宣传和培训以提高农村妇女主任对不同卫生机构的满意程度。