Does regional species diversity resist biotic invasions?

The role of regional species diversity in large-scale species invasions has been largely controversial.On the one hand,it has been proposed that diversity may facilitate invasion(“diversity begets diversity”)because regions with higher diversity may indicate favorable conditions for many more species.On the other hand,high diversity may indicate high levels of niche occupation,thus making it more difficult for new species to invade.In the past,invasion biologists have evaluated how regional native and exotic richness are related.Here,we test whether the range size of exotic species may be constrained by regional native richness using plant data from three continental regions in the Northern Hemisphere,i.e.,Europe,Eastern Asia,and North America.We found that regional native plant diversity is inversely related to the range size of exotic species.This result may be due to stronger species interactions such as competition in species-rich habitats that limit the establishment and spread of exotic species.

应用中国商环包皮环切手术标准化方案对328例成年男性包皮环切的临床报告

目的:成年男性包皮环切手术标准化和培训可显著降低因手术引起的并发症发生率。由于目前国内外尚无可供参考的成年男性包皮环切手术标准化方案和培训制度,使得临床医生开展成年男性包皮环切手术的质量无法保证。为了建立成年男性包皮环切手术标准化和培训制度,便于临床医生和相关医护人员学习和掌握包皮环切器的临床应用技巧,以中国商环(简称"商环,ShangRing")包皮环切技术为例,根据商环的技术特点和临床实践经验,特别制订了商环包皮环切手术标准化方案,并将其标准化操作运用于临床。方法:采用商环包皮环切手术标准化方案对328例受术者(年龄18～58岁,平均27.8岁;已婚134例,未婚194例;包茎25例,包皮过长303例)进行包皮环切手术。对手术时间、疼痛评分(视觉模拟评分法,VAS)、术后并发症、包皮创口愈合时间、术后外观满意情况进行观察和随访。结果:手术时间为(4.70±1.31)min。手术时受术者疼痛(VAS)评分为(0.24±0.59)分,术后24h疼痛评分为(1.59±0.95)分,去环前24h内疼痛评分(1.72±1.11)分,去环时疼痛评分为(2.72±1.37)分。主要并发症发生率为术后感染0.6%(2/328)、出血0.6%(2/328)、伤口裂开0.6%(2/328)和水肿4.89%(16/328)。在发生出血和伤口裂开的受术者中无1例需要缝合。术后包皮创口完全愈合时间为(20.30±6.69)d。受术者对术后外观满意率99.7%(327/328)。结论:商环包皮环切术具有手术方式易于标准化、手术时间短、术中疼痛轻、术后无须特殊护理、容易完整保留系带,并完全暴露冠状沟、术后外观满意度高、受术者易于接受等优点。初步证明了中国商环包皮环切手术标准化方案的可接受性,严格按照此方案实施手术和随访护理,能最大化地实现商环包皮环切技术的诸多临床优势,将并发症发生率控制在可接受的范围内。

贵阳市大气颗粒物(PM_(2.5))污染特征及气象参数的影响

运用连续颗粒物采样仪（URG Model 2000-01J）对贵阳市城区大气颗粒物PM2.5进行了连续3个月（9-11月）的采集与分析,探讨了PM2.5的浓度分布特征、气象条件的影响。结果显示,贵阳市大气颗粒物PM2.5的平均质量浓度为53±27μg/m^3,变化范围为3.7-186μg/m^3;初步推断大气颗粒物PM2.5的污染来源主要是燃料燃烧、生物质燃烧、汽车尾气等人为源;相对湿度、风速、风向、温度等气象条件是影响大气颗粒物浓度及分布的重要因素。

人神经黑色素过度激活小胶质细胞：多巴胺能神经细胞进行性变性的新机制

目的探讨小胶质细胞在中脑黑质致密带(SNpc)人神经黑色素(HNM)导致多巴胺(DA)能神经细胞变性中的作用和机制。方法(1)采用HNM处理中脑胶质细胞重组培养体系,检测DA能神经细胞摄取能力,探讨小胶质细胞对HNM损伤作用的影响。(2)采用小胶质细胞培养体系,通过免疫细胞化学染色、检测免疫炎性及神经毒性因子,从功能及形态上研究HNM对小胶质细胞的激活作用。结果(1)经5.0μg/mL HNM干预后10%、20%和30%小胶质细胞重组培养体系DA能神经细胞摄取能力分别为纯神经细胞培养体系(对照组)的58%、51%和35%,与对照组比较差异有统计学意义(P<0.05);40%、50%和60%星形胶质细胞重组培养体系中DA能神经细胞摄取能力分别为对照组的97%、92%和93%,与对照组比较差异无统计学意义(P>0.05)。(2)经5.0μg/mLHNM干预后中脑神经-胶质细胞混合培养体系中激活的小胶质细胞数为对照组的5.77倍(P<0.05),小胶质细胞体积明显增大,形状不规则,呈棒状和/或阿米巴样,胞浆深染。(3)经5.0μg/mLHNM干预后小胶质细胞产生大量的细胞内活性氧类物质、一氧化氮、肿瘤坏死因子α、白细胞介素1β和前列腺素E2,与对照组比较差异均具有统计学意义(P<0.05)。结论HNM从功能及形态上激活小胶质细胞,促进了DA能神经细胞的进行性变性,为抑制小胶质细胞过度激活成为治疗PD的新靶点提供了一定理论依据。

中国建立男性包皮环切手术标准化和培训的重要性

尽管HIV在非洲的大流行仍然是一个严重的问题,而在其他地区,如亚洲和南美洲,HIV感染率也正在迅速上升。国际健康组织已经认识到有必要制定有效的策略来检测和控制全球HIV的传播。研究表明,男性包皮环切能显著降低HIV、人乳头状瘤病毒(HPV)、单纯疱疹病毒2型(HSV-2)和其他性传播疾病(STD)的感染率。虽然男性包皮环切技术有许多,但是没有标准化的手术方案和培训计划。研究表明,男性包皮环切技术的标准化与培训计划的实施可以大大降低并发症发生率。并发症发生率高是实施男性包皮环切服务的一个主要障碍。我们建议,在推广男性包皮环切之前应建立手术标准和培训计划。

秦淮河流域土地利用/覆被变化对蒸散量变化的贡献

为评估城市化造成的土地利用/覆被类型变化(Land use/cover change,LUCC)对流域尺度蒸散量变化的影响,选取长三角地区秦淮河流域为研究区,基于Landsat系列卫星数据和站点气象数据,构建决策树模型,提取2000年和2013年土地利用/覆被类型数据,同时借助SEBAL模型估算研究区四季典型日(春季:2014-05-26、夏季:2013-08-11、秋季:2013-10-14、冬季:2014-01-02)栅格尺度蒸散,探讨2000-2013年秦淮河流域主要土地利用/覆被类型间转化过程对流域尺度日蒸散量变化的贡献。结果表明:(1)相较于2000年,2013年秦淮河流域不透水面增加183.8%,而水稻田、旱地、林地和水域分别减少19.1%、10.7%、12.8%和9.5%。2000-2013年主要土地利用/覆被类型转化方向包括水稻田→不透水面、旱地→不透水面、水稻田→旱地和旱地→水稻田,转化面积分别为208、168、282和232km^2;(2)仅考虑LUCC的影响,对比2000年,2013年研究区流域尺度日蒸散总量在四季典型日分别减少134万、109万、60万和5万m^3。在春、夏、秋三季典型日,水稻田和旱地向不透水面转化过程造成的贡献率分别为-58.5%、-59.5%、-54.4%和-35.1%、-36.3%、-39.8%,负贡献会抵消旱地向水稻田转化过程造成的正贡献(分别为16.8%、16.3%、5.7%),导致春、夏、秋三季典型日流域尺度日蒸散量下降;而在冬季典型日,水稻田向不透水面、旱地向不透水面和水稻田向旱地转化过程造成的负贡献(分别为-48.8%、-20.5%和-31.8%)会抵消旱地向水稻田转化过程造成的正贡献(26.1%),导致冬季典型日流域尺度日蒸散量下降。总体而言,2000-2013年秦淮河流域城市化带来土地利用/覆被的显著变化,使蒸散较高的水稻田和旱地向蒸散较低的不透水面大面积转化,导致流域尺度日蒸散量在四季均呈下降趋势。

期刊与学术会议论文摘要中报告随机对照试验的CONSORT声明：说明与详述

背景:对于与随机对照试验(randomized controlled trial,RCT)有关的学术会议论文或期刊中发表的文章来说,清楚、明了、信息量充足的摘要是十分重要的,因为读者经常仅仅根据报告的摘要对一个临床试验作出评价。为此,我们需要对"临床试验报告的统一标准(Consolidated Standards of Reporting Trials,CONSORT)声明"进行扩充,制定一个期刊与学术会议论文摘要中报告RCT的必备条目清单。今后在任何期刊发表的论文或学术会议论文摘要中,作者对RCT结果的报告都要包含这些内容。方法与结果:我们根据现有的质量评价工具和基于经验的证据总结出一个条目清单。运用三轮修正式德尔菲法(modified-Delphi process)进行条目筛选。邀请共计109人参与电子网络调查,反馈率为61%。调查结果于2007年1月在加拿大蒙特贝罗举行的CONSORT小组会议中公布,与会的26人中有临床试验实施人员、统计学家、流行病学家以及生物医学编辑。经过讨论最终确定条目,随后对其进行修订以保证这些条目体现了会议期间以及会后的讨论思路。摘要CONSORT建议RCT报告的摘要需要有一个结构化的格式,其中应该包括具体的试验目的、试验设计(随机分配的方法、盲法或遮蔽等)、研究对象(对象描述、随机分组的样本量以及用于分析的样本量)、每组实施的干预、实施的干预对主要疗效结果的影响及其危害、试验结论、试验注册名称和编号以及资金来源。本文对每一条能够找到例子的纳入条目都配有良好报告范例、基本原理以及证据等,十分明了易懂,因此我们建议与清单同时使用。结论:摘要CONSORT旨在改善期刊与学术会议中发表的论文摘要的质量,这将有助于摘要提供详尽清晰的信息,这些信息能够帮助读者对试验的有效性和试验结果的适用性做出正确的评价。

中国5所医院红细胞输注情况病例对照研究

目的调查参加研究的5所医院红细胞输注指征,输血前后血红蛋白（Hb）水平变化以及与红细胞输注相关的其他临床因素,对临床红细胞输注提供科学依据。方法对5家医院的血库信息系统查询2013年全年住院患者中首次红细胞输注病例,并从中随机选择1000例收集相关数据,病例不满1 000例的医院的全部病例纳入研究;将所有数据按照人口统计学特征、并发症、是否手术、红细胞特征以及Hb水平进行区分。根据主要疾病诊断将病例属于6大诊断组的病例分出,选择在同一时间段入院且在相同诊断组的未输血病例为作为对照,进行临床队列研究,对输注前Hb水平及其他红细胞输注相关临床因素进行统计学分析。结果从约5 000例红细胞输注患者中选择出属于6个诊断组的病例1 356例,对照病例1 201例,外科患者（病例数/对照数）包括骨科手术组（312/216）;普外科手术组（367/332）;内科患者包括实体瘤（230/232）;消化道出血（212/221）;心血管疾病（87/77）;血液系统恶性肿瘤（100/101）。Hb水平与手术患者和内科患者的红细胞输注均具有相关性。手术患者中,Hb为（70—90） g/L患者组相对于Hb〉100 g/L患者组,输注红细胞的OR值（95%可信区间）为27. 0（13. 9—52. 7）,内科患者中该OR值为71. 5（37. 8—135. 4）。外科患者红细胞输注只与红细胞输注前Hb水平相关;内科患者中主要诊断、不同医院以及年龄〉75岁等均是进行红细胞输注的独立因素。心血管疾病患者组相对于实体瘤患者组进行红细胞输注的OR值为2. 5（1. 2—4. 9）,血液系统恶性肿瘤患者组与消化道出血患者组相对于实体瘤患者组进行红细胞输注的OR值分别为0. 4（0. 2—0. 6）和0. 5（0. 3—0. 8）。其中46%的血液系统恶性肿瘤患者红细胞输注前的Hb〈60 g/L。结论红细胞输注前Hb水平是与红细胞输注最相关的因素。其他相关临床因素包括年龄、心血管疾病、主要诊断等仅与内科患者的红细胞输注相关,与外科患者红细胞输注无关。比较西方国家红细胞输注标准[输血前Hb：（70—80） g/L]与中国红细胞输注标准（输血前Hb：60 g/L）的临床研究将为科学合理的红细胞输注标准的制定提供依据。

XRCC1 and DNA polymerase β in cellular protection against cytotoxic DNA single-strand breaks

Single-strand breaks （SSBs） can occur in cells either directly, or indirectly following initiation of base excision repair （BER）. SSBs generally have blocked termini lacking the conventional 5＇-phosphate and 3＇-hydroxyl groups and require further processing prior to DNA synthesis and ligation. XRCC1 is devoid of any known enzymatic activity, but it can physically interact with other proteins involved in all stages of the overlapping SSB repair and BER pathways, including those that conduct the rate-limiting end-tailoring, and in many cases can stimulate their enzymatic activities. XRCC1^-/- mouse fibroblasts are most hypersensitive to agents that produce DNA lesions repaired by monofunctional glycosylase-initiated BER and that result in formation of indirect SSBs. A requirement for the deoxyribose phosphate lyase activity of DNA polymerase β （pol β） is specific to this pathway, whereas pol β is implicated in gap-filling during repair of many types of SSBs. Elevated levels of strand breaks, and diminished repair, have been demonstrated in MMS- treated XRCC1^-/-, and to a lesser extent in pol β^-/- cell lines, compared with wild-type cells. Thus a strong correlation is observed between cellular sensitivity to MMS and the ability of cells to repair MMS-induced damage. Exposure of wild-type and polβ^-/- cells to an inhibitor of PARP activity dramatically potentiates MMS-induced cytotoxicity. XRCC1^-/- cells are also sensitized by PARP inhibition demonstrating that PARP-mediated poly（ADP-ribosyl）ation plays a role in modulation of cytotoxicity beyond recruitment of XRCC 1 to sites of DNA damage.

Ubiquitination-mediated protein degradation and modification:an emerging theme in plant-microbe interactions

Post-translational modification is central to protein stability and to the modulation of protein activity. Various types of protein modification, such as phosphorylation, methylation, acetylation, myristoylation, glycosylation, and ubiquitination, have been reported. Among them, ubiquitination distinguishes itself from others in that most of the ubiquitinated proteins are targeted to the 26S proteasome for degradation. The ubiquitin/26S proteasome system constitutes the major protein degradation pathway in the cell. In recent years, the importance of the ubiquitination machinery in the control of numerous eukaryotic cellular functions has been increasingly appreciated. Increasing number of E3 ubiquitin ligases and their substrates, including a variety of essential cellular regulators have been identified. Studies in the past several years have revealed that the ubiquitination system is important for a broad range of plant developmental processes and responses to abiotic and biotic stresses. This review discusses recent advances in the functional analysis of ubiquitination-associated proteins from plants and pathogens that play important roles in plant-microbe interactions.

CONSORT 2010声明:报告平行对照随机临床试验指南的更新

CONSORT声明被广泛用于提高随机对照临床试验的报告质量。Kenneth Schulz等对CONSORT声明的最新版本CONSORT2010作了详细说明,该版本基于新获得的方法学证据和经验的积累对报告指南作了更新。为了鼓励更多的人使用"CONSORT2010声明",本文可从bmj.com免费获取,也将在Lancet,Obstetrics and Gynecology,PLoS Medicine,Annals of Internal Medicine,Open Medicine,Journal of Clinical Epidemiology,BMC Medicine和Trials等杂志发表。

CONSORT 2010说明与详述:报告平行对照随机临床试验指南的更新

大量证据显示随机对照临床试验(randomised controlled trial,RCT)的报告质量不理想。报告不透明,则读者既不能评判试验结果是否真实可靠,也不能从中提取可用于系统综述的信息。最近的方法学分析表明,报告不充分和设计不合理与对治疗效果产生评价偏倚有关。这种系统误差对RCT损害严重,而RCT正是以其能减少或避免偏倚而被视为评价干预措施的金标准。为了提高RCT的报告质量,一个由专家和编辑组成的工作组制定了临床试验报告的统一标准(Consolidated Standards of Reporting Trials,CONSORT)声明。CONSORT声明于1996年首次发表,并于2001年更新。声明由对照检查清单和流程图组成,供作者在报告RCT时使用。许多核心医学期刊和主要国际性编辑组织都已认可CONSORT声明。该声明促进了对RCT的严格评价和解释。2001年,在对CONSORT进行修订时,人们就已经清楚地认识到,解释和说明制定CONSORT声明的原理,有助于研究人员等撰写或评价临床试验报告。一篇CONSORT说明与详述文章于2001年同2001版CONSORT声明一起发表。2007年1月的专家会议之后,对CONSORT声明作了进一步修订并已发表,即"CONSORT2010声明"。这次更新对原版对照检查清单作了文字上的修改,使其更为明晰,并收入了与一些新近才认识到的主题相关的建议,如选择性报告结局产生的偏倚。说明与详述文件旨在加强人们对CONSORT声明的理解、应用和传播,这次也作了大量修订,对每一项新增或更新的清单条目的含义和增改理由进行了解释,提供了优秀的报告实例,还尽可能地提供了相关的经验性研究的参考文献。文中收入了若干流程图实例。"CONSORT2010声明"、其说明与详述文件,以及相关网站(www.consort-statement.org),对于改进随机临床试验报告必将有所裨益。

Experimental and modeling study of de novo formation of PCDD/PCDF on MSW fly ash

The effect of sulfur dioxide （SO2） on the formation of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） has been studied in an entrained-flow reactor （EFR） under simulated waste combustion conditions. A chlorination model based on conditional probability was employed to evaluate the homologue patterns of PCDDs and PCDFs. Results revealed that the presence of SO2 did not alter the formation pathway although SO2 suppressed PCDD/F formation. The prediction model of PCDF showed good agreement with the experimental data （R--0.95）, whereas the prediction for PCDDs did not correlate well with the experimental data. This may be explained because potential chlorination pathways play a significant role in PCDF formation, whereas PCDDs are mainly formed through condensation reactions. Furthermore, the result indicated that the steric hindrance during formation has more effects on PCDD than on PCDF due to the symmetric molecular structures of PCDDs.

关于沉降物中汞来源的进展和不确定性的综合分析

作为第八届全球污染物汞问题国际会议的一部分,一组国际汞问题专家于2005年在威斯康星的麦迪逊召开会议。会议的任务是讨论汞来源的科学依据研究现状。具体讲我们的关键问题是:对某一个指定地点,我们是否有把握确定局地、区域和全球的汞来源的相对份额,自然的相对于人为因素的汞排放和沉降。专家组综合分析了在过去10年来所发表的关于这个问题的最新研究情况,重点在以下4个主要研究课题:长期的人类活动影响的变化,当前的排放和沉降趋势,化学转换与循环,模拟与不确定性。在每一个课题中,专家组都得出一系列的结论,本文对此进行了描述。这些结论同时使得我们对问题的回答是"性质上是",而这种资格取决于所愿意接受的不确定性水平。我们同意这种不确定性主要取决于尺度,以及我们所提出的问题在位于主要点源很近和很远的地方均可得到比较有信心的回答,假设"全球汞库"是被承认的"来源"。从生态系统暴露这个角度来看,很多感兴趣的区域则处于中间地带,带有最大程度的不确定性。

Identification and Quantification of Aerosol Polar Oxygenated Compounds Bearing Carboxylic or Hydroxyl Groups.1.Method Development

In this study,a new analytical technique was developed for the identification and quantification of multifunctional compounds containing simultaneously at least one hydroxyl or one carboxylic group,or both.This technique is based on derivatizing first the carboxylic group(s) of the multifunctional compound using an alcohol (e.g.,methanol,1-butanol) in the presence of a relatively strong Lewisacid (BF3) as a catalyst.This esterification reaction quickly and quantitatively converts carboxylic acids to their ester forms.The second step is based on silylation of the ester compounds using bis(trimethylsilyl) trifluoroacetamide (BSTFA) as the derivatizing agent.For compounds bearing ketone groups in addition to carboxylic and hydroxyl groups,a third step was used based on PFBHA derivatizationof the carbonyls.Different parameters including temperature,reaction time,and effect due to artifacts were optimized.A GC/MS in EI and in methane-CI mode was used for the analysis of these compounds.The new approach was tested on a number of multifunctional compounds.The interpretation of their EI (70 eV) and CI mass spectra shows that critical information is gained leading to unambiguous identification of unknown compounds.For example,when derivatized only with BF3-methanol,their mass spectra comprise primary ions at m/z M ·+ +1,M ·+ +29,and M ·+ - 31 for compounds bearing only carboxylic groups and M ·+ +1,M ·+ +29,M ·+ -31,and M ·+ -17 for those bearing hydroxyl andcarboxylic groups.However,when a second derivatization (BSTFA) was used,compounds bearing hydroxyl and carboxylic groups simultaneously show,in addition to the ions observed before,ions at m/z M ·+ +73,M ·+ -15,M ·+ -59,M ·+ -75,M ·+ -89,and 73.To the best of our knowledge,this technique describes systematically for the first time a method for identifying multifunctional oxygenated compounds containing simultaneously one or more hydroxyl and carboxylic acid groups.

BCL2 inhibits cell adhesion, spreading, and motility by enhancing actin polymerization

BCL2 is best known as a multifnnctional anti-apoptotic protein. However, little is known about its role in cell- adhesive and motility events. Here, we show that BCL2 may play a role in the regulation of cell adhesion, spreading, and motility. When BCL2 was overexpressed in cultured murine and human cell lines, cell spreading, adhesion, and motility were impaired. Consistent with these results, the loss of Bcl2 resulted in higher motility observed in Bcl2- null mouse embryonic fibroblast （MEF） cells compared to wild type. The mechanism of BCL2 regulation of cell adhesion and motility may involve formation of a complex containing BCL2, actin, and gelsolin, which appears to functionally decrease the severing activity of gelsolin. We have observed that the lysate from MCF-7 and NIH3T3 cells that overexpressed BCL2 enhanced actin polymerization in cell-free in vitro assays. Confocal immunofluorescent localization of BCL2 and F-actin during spreading consistently showed that increased expression of BCL2 resulted in increased F-actin polymerization. Thus, the formation of BCL2 and gelsolin complexes （which possibly contain other proteins） appears to play a critical role in the regulation of cell adhesion and migration. Given the established correlation of cell motility with cancer metastasis, this result may explain why the expression Of BCL2 in some tumor cell types reduces the potential for metastasis and is associated with improved patient prognosis.

The fidelity of DNA synthesis by eukaryotic replicative and translesion synthesis polymerases

In their seminal publication describing the structure of the DNA double helix , Watson and Crick wrote what may be one of the greatest understatements in the scientific literature, namely that ＂It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.＂ Half a century later, we more fully appreciate what a huge challenge it is to replicate six billion nucleotides with the accuracy needed to stably maintain the human genome over many generations. This challenge is perhaps greater than was realized 50 years ago, because subsequent studies have revealed that the genome can be destabilized not only by environmental stresses that generate a large number and variety of potentially cytotoxic and mutagenic lesions in DNA but also by various sequence motifs of normal DNA that present challenges to replication. Towards a better understanding of the many determinants of genome stability, this chapter reviews the fidelity with which undamaged and damaged DNA is copied, with a focus on the eukaryotic B- and Y-family DNA polymerases, and considers how this fidelity is achieved.

Burden and outcomes for complex perianal fistulas in Crohn's disease:Systematic review

AIM To systematically review the literature on epidemiology,disease burden, and treatment outcomes for Crohn's disease(CD) patients with complex perianal fistulas.METHODS PubMed, Embase, and Cochrane were searched for relevant articles(published 2000-November 2016) and congress abstracts(published 2011-November 2016).RESULTS Of 535 records reviewed, 62 relevant sources were identified(mostly small observational studies). The cumulative incidence of complex perianal fistulas in CD from two referral-centre studies was 12%-14%(follow-up time, 12 years in one study; not reported in the second study). Complex perianal fistulas result in greatly diminished quality of life; up to 59% of patients are at risk of faecal incontinence. Treatments include combinations of medical and surgical interventions and expanded allogeneic adipose-derived stem cells. High proportions of patients experience lack of or inadequate response to treatment(failure and relapse rates,respectively: medical, 12%-73% and 0%-41%; surgical:0%-100% and 11%.20%; combined medical/surgical:0%-80% and 0%-50%; stem cells: 29%-47% and not reported). Few studies(1 of infliximab; 3 of surgical interventions)have been conducted in treatment-refractory patients, a population with high unmet needs. Limited data exist on the clinical value of anti-tumour necrosis factor-α dose escalation in patients with complex perianal fistulas in CD.CONCLUSION Complex perianal fistulas in CD pose substantial clinical and humanistic burden. There is a need for effective treatments, especially for patients refractory to antitumour necrosis factor-α agents, as evidenced by high failure and relapse rates.

Low skeletal muscle mass is associated with non-alcoholic fatty liver disease in Korean adults： the Fifth Korea National Health and Nutrition Examination Survey

BACKGROUND： Sarcopenia and non-alcoholic fatty liver dis- ease （NAFLD） share similar pathophysiological mechanisms, and the relationship between sarcopenia and NAFLD has been recently investigated. The study investigated whether low skel- etal muscle mass is differentially associated with NAFLD by gender in Korean adults. METHODS： We conducted a cross-sectional analysis of the data from the Fifth Korea National Health and Nutrition Examination Survey. The skeletal muscle index （SMI） was obtained by the appendicular skeletal muscle mass divided by the weight. NAFLD was defined as a fatty liver index （FLI） 〉60 in the absence of other chronic liver disease. RESULTS： Among the included subjects, 18.3% （SE： 1.4%） in men and 7.0% （SE： 0.7%） in women were classified as having FLI-defined NAFLD. Most of the risk factors for FLI-defined NAFLD showed a significant negative correlation with the SMI in both genders. Multiple logistic regression analysis showed that low SMI was associated with FLI-defined NAFLD, inde- pendent of other metabolic and lifestyle parameters in both genders [males： odds ratio （OR）=1.35; 95% confidence inter- val （CI）： 1.17-1.54; females： OR=1.36; 95% CI： 1.18-1.55]. The magnitude of the association between FLI-defined NAFLD and low SMI was higher in middle aged to elderly males （OR-1.50; 95% CI： 1.22-1.84） than in males less than 45 years of age （OR=1.25; 95% CI： 1.02-1.52） and in premenopausal females （OR=l.50; 95% CI： 1.12-2.03） than in postmenopausal females （OR-1.36; 95% CI： 1.20-1.54）.CONCLUSIONS： Low SMI is associated with the risk of FLI- defined NAFLD independent of other well-known metabolic risk factors in both genders. This association may differ ac- cording to age group or menopausal status. Further studies are warranted to confirm this relationship.