High rates of double-stranded RNA viruses and Mycoplasma hominis in Trichomonas vaginalis clinical isolates in South Brazil

Trichomonas vaginalis is the etiological agent of trichomoniasis, the most common non-viral sexually transmitted disease (STD) in world, with 276.4 million new cases each year. T. vaginalis can be naturally infected with Mycoplasma hominis and Trichomonasvirus species. This study aimed to evaluate the prevalence of T. vaginalis infected with four distinct T. vaginalis viruses (TVVs) and M. hominis among isolates from patients in Porto Alegre city, South Brazil. An additional goal of this study was to investigate whether there is association between metronidazole resistance and the presence of M. hominis during TVV infection. The RNA expression level of the pyruvate ferredoxin oxidoreductase (PFOR) gene was also evaluated among metronidazole-resistant and metronidazole-sensitive T. vaginalis isolates. A total of 530 urine samples were evaluated, and 5.7% samples were positive for T. vaginalis infection. Among them, 4.51% were isolated from female patients and 1.12% were from male patients. Remarkably, the prevalence rates of M. hominis and TVV-positive T. vaginalis isolates were 56.7% and 90%, respectively. Most of the T. vaginalis isolates were metronidazole-sensitive (86.7%), and only four isolates (13.3%) were resistant. There is no statistically significant association between infection by M. hominis and infection by TVVs. Our results refute the hypothesis that the presence of the M. hominis and TVVs is enough to confer metronidazole resistance to T. vaginalis isolates. Additionally, the role of PFOR RNA expression levels in metronidazole resistance as the main mechanism of resistance to metronidazole could not be established. This study is the first report of the T. vaginalis infection by M. hominis and TVVs in a large collection of isolates from South Brazil.     

Trichomonas vaginalis: alternative pathway activation of complement

Serum from adult human donors lysed Trichomonas vaginalis. The lytic effect was eliminated by heat-inactivation of serum (56 °C, 30 min). No serum donor exhibited significantly increased antibody against the parasite as measured by indirect immunofluorescence. Treatment of serum with ethylene glycol-bis (B-aminoethyl ether)-N, N-tetraacetic acid to eliminate classical pathway complement activation did not prevent C3→C3i conversion in serum incubated with T. vaginalis. Release of complement products during alternative pathway activation may contribute to pathogenesis of trichomonal vaginitis.     

阴道毛滴虫长期培养传代的实验观察

目的 观察阴道毛滴虫长期传代培养的适宜条件,为教学、科研提供实验虫株. 方法制备肝浸液培养基,改良培养方法,接种培养后,观察虫的密度与培养时间、培养基体积、培养温度以及灭活血清和未灭活血清对虫株发育繁殖的影响.结果 本实验成功培养传代达3年以上,前期培养1年内,虫株适应新的生长环境.后期为培养1年后,虫株培养达到稳定,优化培养条件,培养保存时间达到16天.结论 长期传代培养阴道毛滴虫,适当降低培养温度、减少培养基内虫体的密度、增加培养基体积能有效的延长体外培养时间.     

阴道毛滴虫感染因素分析及预防对策

目的 分析阴道毛滴虫感染的相关因素,并总结预防对策.方法 选择2011年5月-2012年5月在医院妇科门诊就诊的486例成年女性,用生理盐水涂片法检查阴道毛滴虫感染情况,对所有女性的年龄、就诊季节、婚姻状况、职业、卫生习惯等进行统计分析.结果 所检测的486份标本中,阴道毛滴虫阳性有42份,阳性率为8.6％;36～40岁的女性感染率阴道毛滴虫的概率最高,为13.8％;春季的感染率最高,为13.1％;已婚女性感染率明显高于未婚女性,已婚女性感染率为10.4％;从事农业的女性感染阴道毛滴虫的概率高于其他职业,为15.1％;经常清洁外阴的女性感染率要明显低于其他女性,为5.7％.结论 阴道毛滴虫感染与年龄、季节、婚姻状况、职业、卫生习惯等各方面因素有着密切关系,要预防阴道毛滴虫的感染,必须要注意几个因素的影响,综合进行预防阴道毛滴虫感染.     

Transmission of Trichomonas vaginalis in swimming pools?

Summary Trichomonas vaginalis could not be isolated from the water of a highly frequented swimming pool of the City of Zurich.The protozoon T. vaginalis may show a slight degree of motility; even after 20 minutes exposure to the chlorinated water of a swimming pool; but it looses its infectivity within seconds after exposure to water of the swimming pool.It is not yet known how trichomonades are able to survive in the secretions of the vagina and on contaminated objects (fomites) in dressing rooms.

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Infection avec Trichomonades dans une piscine

Résumé Nous n'avons décelé aucun Trichomonas dans l'eau de la piscine City-Hallenbad, à Zurich, mÊme lors de jours de forte affluence.Dans l'eau de piscine contaminée artificiellement par des protozoaires, ceux-ci ne restent mobiles qu'une vingtaine de minutes, prennent une forme sphérique et perdent leur pouvoir infectieux.La durée de l'infectiosité d'objets (linges et bancs) souillés par des sécrétions vaginales n'a pas encore pu Être établie.

     

A preliminary investigation of microsatellite-based genotyping in Trichomonas vaginalis

The genetic epidemiology of Trichomonas vaginalis is poorly understood at present. The recent release of the organism's genome sequence opens the way to investigation of polymorphic markers allowing strain identification. We here report a preliminary analysis of microsatellite loci in T. vaginalis and show that this approach holds promise for future studies of infection transmission and organism diversity.     

不同pH值对阴道毛滴虫体外培养的影响

目的 观察阴道毛滴虫在不同的pH值培养基中的培养效果。方法 阴道毛滴虫在pH5.8,6.2,6.6,7.0四组不同培养基中37℃恒温培养，每隔24h观察虫数，活率并计算活虫数。结果 pH7.0组培养第2-4天虫数，活虫数，活率均明显低于其它三组，且在培养过程中无明显活虫数及活率高峰，阴道毛滴虫在培养基中能存活生长10天，其余三组均只生长存活6天，第1-4天，pH6.6组活虫数，活率均高于其它三组。结论 pH7.0不适宜阴道毛滴虫体外培养，pH6.6时，培养各项指标均较好。可能更适合阴道毛滴虫体外培养。     

Epidemic cholera in West Africa: the role of food handling and high-risk foods

During an epidemic of cholera in Guinea, West Africa, in 1986, the authors conducted two studies of risk factors for transmission. In the capital city, 35 hospitalized cholera patients were more likely than 70 neighborhood-matched controls to have eaten leftover peanut sauces (odds ration (OR) = 3.1, 95% confidence interval (CI) 1.2-8.2), but less likely to have eaten tomato sauces (OR = 0.2, 95 percent CI 0.1-0.9). Hand washing with soap before meals by all family members protected against cholera (OR = 0.2, 95 percent CI 0.02-0.96), suggesting that persons asymptomatically infected with Vibrio cholerae 01 may have been the initial source for contamination of the leftover foods. Laboratory studies demonstrated that V. cholerae multiplied rapidly in peanut sauce (pH 6.0), but not in the more acidic tomato sauce (pH 5.0). In an outbreak of cholera-like illness after a rural funeral, illness was strongly associated with eating a rice meal served over many hours without reheating. These studies demonstrated that, in this epidemic, many cases of severe cholera were associated with eating specific cooked foods that could support bacterial growth after contamination of these foods with V. cholerae within the household. Epidemic control efforts should include identification of high-risk foods and promotion of simple changes in food handling behaviors to lower the risk of foodborne transmission.     

阴道毛滴虫ITS序列多态性与甲硝唑耐药性

目的 探讨临床不同分离株阴道毛滴虫核糖体DNA基因转录间隔区(rDNA ITS)序列多态性与甲硝唑抗性表型之间的相关性。方法 采用微孔板法检测39株达到纯培养的阴道毛滴虫虫株对甲硝唑敏感性,同时设计rDNA-ITS区特异引物进行PCR扩增并测序。结果 39个虫株中,甲硝唑敏感虫株20株,耐药虫株19株;PCR扩增获得ITS区和5.8 S特异片段长度为285 bp。经DNAStarMeg Align比对显示,仅在ITS1区存在唯一点突变,即C66T突变。39个虫株中有8株具C66T突变,其中6株来自甲硝唑敏感虫株,2株来自甲硝唑耐药虫株。经Fisher确切概率检验,χ²=0.108,P>0.05。结论 阴道毛滴虫临床分离株ITS区C66T突变与甲硝唑抗性表型无明显相关性。     

Aflatoxin Exposure and Viral Hepatitis in the Etiology of Liver Cirrhosis in The Gambia,West Africa

Background

Cirrhosis of the liver is thought to be a major cause of morbidity and mortality in sub-Saharan Africa, but few controlled studies on the etiology of cirrhosis have been conducted in this region.

Objectives

We aimed to elucidate the association between environmental and infectious exposures and cirrhosis in The Gambia.

Methods

Ninety-seven individuals were diagnosed with cirrhosis using a validated ultrasound scoring system and were compared with 397 controls. Participants reported demographic and food frequency information. Blood samples were tested for hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), hepatitis C virus (HCV) antibody, HCV RNA, and the aflatoxin-associated 249^ser TP53 mutation.

Results

HBsAg seropositivity was associated with a significant increase in risk of cirrhosis [odds ratio (OR) = 8.0; 95% confidence interval (CI), 4.4–14.7] as was the presence of HBeAg (OR = 10.3; 95% CI, 2.0–53.9) and HCV infection (OR = 3.3; 95% CI, 1.2–9.5). We present novel data that exposure to aflatoxin, as assessed both by high lifetime groundnut (peanut) intake and by the presence of the 249^ser TP53 mutation in plasma, is associated with a significant increase in the risk for cirrhosis (OR = 2.8; 95% CI, 1.1–7.7 and OR = 3.8; 95% CI, 1.5–9.6, respectively). Additionally, aflatoxin and hepatitis B virus exposure appeared to interact synergistically to substantially increase the risk of cirrhosis, although this was not statistically significant.

Conclusions

Our results suggest that the spectrum of morbidity associated with aflatoxin exposure could include cirrhosis.     

生殖器支原体在HIV高危人群中的流行进展

生殖器支原体(Mg)是性传播疾病的病原之一,可引起男性非淋球菌性尿道炎、女性宫颈炎、子宫内膜炎及盆腔炎.近年来发现泌尿生殖道Mg感染在HIV阳性及高危人群中的流行呈上升趋势,并且Mg感染可能促进HIV的感染与传播,提示应对HIV高危人群的Mg感染给予充分的重视.此文就Mg在HIV阳性及高危人群中的流行情况及治疗的研究进展进行了综述.     

Prevalence of Mycoplasma genitalium, Mycoplasma hominis and Chlamydia trachomatis among Danish patients requesting abortion

The aim of the study was to determine lower genital tract carriage rate of Mycoplasma genitalium (M. genitalium) and to compare it to the carriage rates of Mycoplasma hominis (M. hominis ) and Chlamydia trachomatis (C. trachomatis) among 102 women requesting termination of pregnancy at the Horsens Hospital in Denmark. Real-Time PCR was used for the detection of bacterial DNA, and the presence of antibodies to the three microorganisms was determined by ELISA and immunoblotting. Real-Time PCR detected M. genitalium in one swab sample (0.98%) only, while the prevalence of C. trachomatis was high (15.69%) and M. hominis colonization (18.63%) was similar to colonization observed among sexually experienced adults. There was a significant difference in prevalence of M. hominis infection in the different age groups. C. trachomatis load in the cervical samples was significantly higher among young patients. There was no correlation between the presence of genital infection with C. trachomatis and genital mycoplasmas and no correlation between the presence of antibodies to these bacteria. In conclusion, in Danish patients it is not necessary to test for M. genitalium before abortion since less than 1% were found positive. The prevalence of genital C. trachomatis infections was high among the abortion-seeking patients.     

生殖支原体黏附素蛋白模拟表位的筛选和鉴定

目的制备兔抗重组生殖支原体粘附素蛋白(rMgPa)的多克隆抗体(pAb),以期筛选MgPa的模拟表位。方法用rMgPa免疫新西兰兔以制备兔抗rMgPa的pAb,以此pAb为靶分子对噬菌体展示随机12肽库进行生物淘洗,随机挑取74个噬菌体克隆进行DNA测序与分析,用ELISA检测噬菌体与pAb结合的特异性。结果制备了兔抗rMgPa的特异性pAb,以此抗体为靶分子对噬菌体展示肽库进行生物淘洗后,特异性噬菌体克隆得到了明显富集。经对74个噬菌体克隆所展示的外源性多肽序列进行比较分析,共可大致分为3组一致性的核心序列:P-S-A-A/V-X-R-F/W-E/S-L-S-P,A-K-I/L-T/Q-X-T-L-X-L和K-S-L-S-R-X-D-X-I。ELISA结果说明36个噬菌体克隆能与pAb发生特异性结合,因此,这三组核心序列可能是MgPa的模拟表位。结论成功制备了兔抗rMg-Pa的pAb,并筛选到MgPa的3个可能的模拟表位,为进一步研究Mg的诊断与预防提供一定的实验依据。     

Population structure and genetic diversity of the parasite Trichomonas vaginalis in Bristol,UK

The protozoan parasite Trichomonas vaginalis is the causative agent of trichomoniasis, an extremely common, but non-life-threatening, sexually-transmitted disease throughout the world. Recent population genetics studies of T. vaginalis have detected high genetic diversity and revealed a two-type population structure, associated with phenotypic differences in sensitivity to metronidazole, the drug commonly used for treatment, and presence of T. vaginalis virus. There is currently a lack of data on UK isolates; most isolates examined to date are from the US. Here we used a recently described system for multilocus sequence typing (MLST) of T. vaginalis to study diversity of clinical isolates from Bristol, UK. We used MLST to characterise 23 clinical isolates of T. vaginalis collected from female patients during 2013. Seven housekeeping genes were PCR-amplified for each isolate and sequenced. The concatenated sequences were then compared with data from other MLST-characterised isolates available from http://tvaginalis.mlst.net/ to analyse the population structure and construct phylogenetic trees. Among the 23 isolates from the Bristol population of T. vaginalis, we found 23 polymorphic nucleotide sites, 25 different alleles and 19 sequence types (genotypes). Most isolates had a unique genotype, in agreement with the high levels of heterogeneity observed elsewhere in the world. A two-type population structure was evident from population genetic analysis and phylogenetic reconstruction split the isolates into two major clades. Tests for recombination in the Bristol population of T. vaginalis gave conflicting results, suggesting overall a clonal pattern of reproduction. We conclude that the Bristol population of T. vaginalis parasites conforms to the two-type population structure found in most other regions of the world. We found the MLST scheme to be an efficient genotyping method. The online MLST database provides a useful repository and resource that will prove invaluable in future studies linking the genetics of T. vaginalis with the clinical manifestation of trichomoniasis.     

3种药物体外抗阴道毛滴虫作用比较观察

目的 观察青蒿琥酯、奥硝唑和甲硝唑3种药物体外抗阴道毛滴虫的作用.方法 用原虫培养液将阴道毛滴虫稀释,配成密度为2万/ml的细胞悬液,定量分装到96孔细胞培养板上,每孔0.1ml(含虫2000个).设对照组和实验观察组,对照组各孔加入0.1ml培养液;实验组中加入等量不同浓度的青蒿琥酯、奥硝唑和甲硝唑,用MTT法检测药物体外抗虫效果.结果 药物作用24h后,当青蒿琥酯、奥硝唑和甲硝唑的作用浓度分别为60μg/ml、50μg/ml和400μg/ml时,对虫体的相对抑制率约为17%;而在高浓度时,甲硝唑(2500μg/ml)的相对抑制率可达51.2%,显效非常明显,但奥硝唑(2500/μg/ml)和青蒿琥酯(6000μg/m1)的相对抑制率仅为32.8%和30.4%.结论 青蒿琥酯、奥硝唑和甲硝唑对体外培养阴道毛滴虫均表现出一定的抗虫效应;青蒿琥酯和奥硝唑的显效作用浓度较低,而高浓度的甲硝唑抗虫效应较好.