腹泻患者艰难梭菌及其毒素A/B检出率分析

目的了解住院腹泻患者艰难梭菌及其毒素A/B的检出情况,为临床诊断抗生素相关性腹泻提供参考依据。方法收集2015年9月至2016年8月崇州市人民医院疑似抗生素相关性腹泻住院患者的粪便标本163份,用艰难梭菌快速检测试剂盒检测艰难梭菌特异性抗原谷氨酸脱氢酶(GDH);用酶联免疫荧光法检测GDH阳性标本中艰难梭菌毒素A/B的产生情况。结果 163份粪便标本中GDH阳性为34份,阳性率为20.86%。34份GDH阳性标本中艰难梭菌毒素A/B阳性率为41.18%(14/34),可疑阳性率为17.65%(6/34),阴性率为41.18%(14/34)。结论疑似抗生素相关性腹泻住院患者艰难梭菌GDH检出率较高,毒素A/B阳性率也比较高,提示临床应重视抗生素相关性腹泻患者艰难梭菌感染的诊断。     

艰难梭菌感染与大肠癌及大肠腺瘤的 相关性分析

目的分析艰难梭菌感染与大肠癌及大肠腺瘤的相关性,为临床预防及治疗肠道肿瘤提供新思路。方法收集2016年1月至2017年6月于甘肃省人民医院就诊的134例大肠癌患者、52例大肠腺瘤患者及100例健康对照者的粪便标本及临床资料,对粪便标本进行细胞毒性试验检测,分析大肠癌及大肠腺瘤与艰难梭菌感染的相关性。同时分析艰难梭菌感染与大肠癌临床特征及部分样本免疫组化(Her-2、P53、CDX2、CD56及Ki-67)结果的相关性。结果 (1)结直肠癌组检出13例艰难梭菌感染者(9.70%),大肠腺瘤组检出2例艰难梭菌感染者(3.85%),对照组未检出艰难梭菌感染者。结直肠癌组艰难梭菌感染率明显高于大肠腺瘤组及对照组(χ~2=11.0953,P0.05)。(2)艰难梭菌感染与结直肠癌病理分期具有相关性,其中Ⅰ、Ⅱ期共检出1例感染者(1.9%),Ⅲ、Ⅳ期共检出12例感染者(14.8%),二者差异有统计学意义(χ~2=3.8963,P0.05)。艰难梭菌感染与结直肠癌大体位置、大体形态、组织学分型、分化程度均无相关性(P0.05)。(3)CDX2的表达与艰难梭菌感染具有相关性,CDX2阴性结直肠癌患者艰难梭菌感染率明显高于CDX2阳性患者(20.8%vs 2.8%,χ~2=8.5224,P0.05);艰难梭菌感染与Her-2、P53、CD56及Ki-67之间无相关性(P0.05)。结论艰难梭菌感染与大肠癌的发生具有相关性,特别是与大肠癌病理分期及CDX2表达存在相关性。艰难梭菌感染与大肠腺瘤之间无显著相关性。     

粪便标本艰难梭菌三种培养方法的比较

目的比较粪便标本中艰难梭菌三种培养方法的差异性,寻找适合临床实验室使用的艰难梭菌培养方法。方法将健康儿童的300份粪便标本分别用快速芽孢孵育法、乙醇直接处理法、富集芽孢培养法进行培养,并对三种培养方法的差异性进行统计学比较。结果 300份粪便标本快速芽孢孵育法培养出艰难梭菌51例,检出率为17.0%;乙醇直接处理法培养出48例,检出率为16.0%;富集芽孢培养法培养出44例,检出率为14.7%。三种方法的检出率差异无统计学意义(P=0.7352,P0.05)。结论乙醇直接处理法、快速芽孢孵育法简单快速,适合临床实验室进行艰难梭菌的快速培养;富集芽孢培养法杂菌少,适合大量艰难梭菌培养便于结果的观察及进一步的处理。     

住院非腹泻儿童艰难梭菌的定植及相关特征

目的了解石家庄地区住院非腹泻儿童艰难梭菌的定植率、毒素产生及核糖体分型特征,并与本地区成人艰难梭菌感染(Clostridium difficile infection,CDI)患者中分离的菌株进行同源性分析。方法采用改良快速肉汤孵育法对2011年10月至2012年6月石家庄三所医院的601份粪便标本进行厌氧培养,筛选出艰难梭菌;应用PCR方法检测A、B毒素基因并进行核糖体分型,Ntsys PC 2.0软件进行同源性分析。结果 601份住院非腹泻儿童粪便标本的艰难梭菌定植率为25.3%(152/601),其中产毒株定植率为18.3%(110/601);2岁以下婴儿与2~18岁儿童定植率分别为20.6%(81/394)、34.3%(71/207)。PCR核糖体分型共分有23个型别,其中6种主要型别的菌株占82.2%(125/152)。与该地区成人CDI患者来源菌株的12个型别相比,有10个型别相同。结论石家庄地区住院非腹泻儿童艰难梭菌的定植率不同年龄段有差异,产毒株的定植率较高,且与引起成人CDI的菌株有同源性。提示艰难梭菌可能在儿童与成人间相互传播,尤其是无症状儿童作为艰难梭菌的储存库可能会污染医院环境,成为医院感染的潜在因素。     

腹泻患儿粪便中A群轮状病毒抗原阳性率及其相关因素分析

目的回顾性分析我院腹泻患儿粪便中A群轮状病毒抗原检测情况,为临床提供快捷、准确、可靠的诊断依据。方法收集腹泻患儿粪便标本2 869例,应用免疫层析双抗体夹心法检测A群轮状病毒抗原,对阳性率及其影响因素进行统计分析。结果2 869例检测结果中阳性946例,总阳性率为32.9%。1~2岁患儿阳性率最高,为36.5%;0~1岁阳性率其次,为32.3%;2~6岁患儿阳性率相对较低,为27.0%。不同年龄段间比较差异具有统计学意义(χ2=11.17,P0.05)。秋冬季节为轮状病毒感染率的高峰期,春夏季节较低,分别为39.5%和22.6%。不同季节两组间比较差异具有统计学意义(χ2=10.15,P0.05)。并且发现粪便以黏液便或水样便为特征的患儿A群轮状病毒感染率较高。结论轮状病毒是婴幼儿急性重症腹泻的主要病原体之一,及时进行轮状病毒抗原检测,对腹泻患儿的及时诊断和合理预防治疗具有重要意义。     

ICU患者艰难梭菌分离培养与 流行病学特征研究

目的了解ICU患者艰难梭菌的定植和感染情况,为预防艰难梭菌的流行提供参考。方法收集2016年9月至2017年6月福建医科大学附属第一医院ICU中139例住院时间7d的患者的粪便样本,对其进行选择性厌氧培养和质谱鉴定。对艰难梭菌培养阳性标本进行毒素基因(tcdA、tcdB、cdt A、cdtB)的PCR检测以及毒素A、B表型检测。收集所有患者的临床资料,并对艰难梭菌培养阳性患者的临床特征和实验室检查结果进行单因素分析和多因素回归分析。结果艰难梭菌检出率为17.27%(24/139)。其中,14株艰难梭菌的tcdA和tcdB基因检测阳性,占58.3%(14/24);10株为tcdA和tcdB基因检测阴性,占41.7%(10/24)。所有菌株二元毒素基因(ctdA/ctdB)均未检出。单因素分析提示,高龄、长时间住院、高淋巴细胞数、使用β-内酰胺类抗生素是艰难梭菌定植的高危因素;多因素回归分析提示,使用β-内酰胺类抗生素是艰难梭菌定植的独立危险因素(OR=3.881,P=0.039)。结论我院ICU可能存在艰难梭菌感染和传播的风险,对具有高龄、长期住院以及使用抗生素等高危因素的患者应进行艰难梭菌的监测,以防艰难梭菌的传播、感染和艰难梭菌相关性腹泻的发生。     

上海部分地区儿童艰难梭菌相关性腹泻的临床分析

本文旨在监测儿童腹泻中艰难梭菌相关性腹泻(CDAD)的发病情况,并对其进行回顾性临床分析。对复旦大学附属儿科医院2007年2月～9月111例腹泻患儿的粪便标本进行艰难梭菌毒素A检测及粪便厌氧菌培养,对所有患儿进行回顾性病史采集及分析,并对粪便培养所得的4株艰难梭菌菌株用多位点可变数目串联重复序列分析(MLVA)技术进行同源性分析。111例患者中,艰难梭菌毒素A检测及艰难梭菌培养均为阳性者无,艰难梭菌毒素A阳性而艰难梭菌培养阴性者16例,艰难梭菌毒素A阴性而艰难梭菌培养阳性者4例,艰难梭菌毒素A及艰难梭菌培养均阴性者91例。比较院内、院外组3种不同病程腹泻CDAD的发病率,无显著差异。MLVA分析发现粪便培养得到的4株艰难梭菌菌株有部分同源性。结果提示,目前上海部分地区儿童CDAD发病情况为散发,但彼此之间有部分同源性;院内、外获得性腹泻的CDAD发病率无显著差异;艰难梭菌毒素A阳性或艰难梭菌培养阳性的病例在临床表现上与艰难梭菌毒素A阴性且艰难梭菌培养阴性的腹泻病例无显著差异。     

时间对微生物标本检验阳性率的影响分析

目的:对不同检验时间的临床微生物标本的阳性率进行探讨。方法:回顾性分析我院2013年12月至2014年5月间住院治疗的2106例患者在不同检验时间进行临床微生物检验的临床资料。结果:第一时间血培养标本、非呼吸道标本的阳性检出率明显高于第二时间(10.23%/6.25%、35.16%22.14%),差异有统计学意义(P0.05);且第一时间呼吸道标本阳性率明显低于第二时间呼吸道标本的阳性率(28.92%/36.29%),差异有统计学意义(P0.05);但两时间粪便标本阳性率相同,均为2.40%。结论:对于临床微生物标本应尽量做到立即送检,以减少微生物繁殖、厌氧菌的过度生长等对微生物检验准确性的影响;同时,要加强临床检验人员专业素养、提升技术水平,从而提高微生物检验质量,为感染性疾病的诊治提供有利依据。     

布拉氏酵母菌散剂预防婴幼儿抗菌药物 相关性腹泻临床观察

目的观察布拉氏酵母菌散剂预防婴幼儿抗菌药物相关性腹泻(antibiotic-associated diarrhea,AAD)的临床疗效。方法将168例应用抗菌药物治疗的支气管肺炎患儿随机分为两组,对照组78例,给予常规抗感染治疗;预防组90例,在对照组常规抗感染治疗基础上加服布拉氏酵母菌散剂,服用剂量:年龄6月,0.25 g/d;~1岁,0.5 g/d;~3岁,0.5 g/d,均分为2次服用,疗程7~10 d。比较两组腹泻的发生率,观察两组患儿治疗1周后唾液分泌型免疫球蛋白A含量的变化。结果对照组78例发生腹泻34例(43.59%),预防组90例发生腹泻17例(18.89%),两组比较差异有统计学意义(χ2=8.041,P0.01);对照组发生腹泻次数为(5.38±1.50)次/d,预防组为(3.68±1.10)次/d,两组比较差异有统计学意义(t=3.239,P0.01);对照组腹泻平均持续时间为(4.84±1.32)d,预防组(3.73±1.33)d,两组比较差异有统计学意义(t=2.245,P0.05)。1周治疗后,对照组的唾液s Ig A治疗后较治疗前显著降低(t=2.769,P0.01),而预防组的治疗后与治疗前比较差异无统计学意义(t=0.488,P0.05)。结论布拉氏酵母菌散剂能有效预防婴幼儿AAD。     

2016年吉林省健康从业人员麻疹和风疹抗体水平调查分析

目的调查分析吉林省2016年健康从业人员的麻疹(measles)和风疹(rubella)的抗体水平。方法采用方便抽样的方法,采集吉林省2016年各地区18岁及以上健康从业人员1 419人的血清,检测其麻疹和风疹的IgG抗体,进行描述性分析。结果 2016年吉林省健康从业人员麻疹IgG抗体阳性率为91.26%,风疹IgG抗体阳性率为81.46%。麻疹和风疹报告病例的时间分布,主要流行季节均在春季。吉林省8个地市麻疹IgG抗体阳性率在82.00%～98.00%之间,差异有统计学意义(χ~2=35.59,P<0.05);风疹IgG抗体阳性率在63.75%～86.24%,差异有统计学意义(χ~2=37.49,P<0.05)。男性与女性麻疹IgG抗体阳性率分别为92.64%和90.70%,性别差异无统计学意义(χ~2=1.38、P=1.42,P>0.05);男性与女性的风疹IgG抗体阳性率分别为82.84%和80.91%,性别差异无统计学意义(χ~2=0.72,P=0.22,P>0.05)。各年龄组麻疹IgG抗体阳性率在88.73%～100.00%之间,年龄差异无统计学意义(χ~2=7.11、P=0.21,P>0.05);风疹IgG抗体阳性率在75.00%～88.89%之间,年龄差异无统计学意义(χ~2=11.24、P=0.47,P>0.05)。结论 2016年吉林省健康从业人员麻疹和风疹的IgG抗体阳性率未达到可形成免疫屏障的水平,建议对该人群开展麻疹和风疹疫苗加强免疫。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.