Amnion cells engineering: A new perspective in fetal membrane healing after intrauterine surgery?

In this study we aimed to set up an in vitro culture of the rabbit amnion in order to support in vivo fetal membrane healing capacity following fetoscopy. Fetal membranes were collected from a mid- gestational rabbit, and cultured on collagen support material for 14 days. 34 rabbits at 22 - 23 days gestational age ( GA) underwent fetoscopy. The entry site was randomly allocated to 4 closure technique study groups: group I, human amnion membrane ( n = 23); group II, collagen foil ( n = 16); group III, collagen plug ( n = 19), and group IV, collagen plug with cultured amnion cells ( n = 19). In all groups membrane access sites were additionally sealed with fibrin sealant, and the myometrium was closed with sutures. Fetal survival, amnion membrane integrity, and the presence of amniotic fluid were evaluated at 30 days GA. Cultures showed good survival in the collagen support material. Increased cellularity, survival and proliferations were observed. The amnion at the access site resealed in 58 - 64% of cases in groups II - IV, but none of the tested techniques was significantly better than the other. Histological examination indirectly revealed the anatomic repair of the membranes, since no entrapment of the membranes could be demonstrated in the myometrial wound. Copyright (c) 2006 S. Karger AG, Basel

Genotype-specific Concordance of Chlamydia trachomatis Genital Infection within Heterosexual Partnerships

Background Sexual transmission rates of Chlamydia trachomatis (Ct) cannot be measured directly; however, the study of concordance of Ct infection in sexual partnerships (dyads) can help to illuminate factors influencing Ct transmission. Methods Heterosexual men and women with Ct infection and their sex partners were enrolled and partner-specific coital and behavioral data collected for the prior 30 days. Microbiological data included Ct culture, nucleic acid amplification testing (NAAT), quantitative Ct polymerase chain reaction (qPCR), and ompA genotyping. We measured Ct concordance in dyads, and factors (correlates) associated with concordance. Results 121 women and 125 men formed 128 dyads. Overall, 72.9% of male partners of NAAT-positive women and 68.6% of female partners of NAAT-positive men were Ct-infected. Concordance was more common in dyads with culture-positive members (78.6% of male partners, 77% of female partners). Partners of women and men who were NAAT-positive only had lower concordance (33.3%, 46.4%, respectively). Women in concordant dyads had significantly higher median endocervical qPCR values (3,032) compared with CT-infected women in discordant dyads (1,013 IFU DNA equivalents per ml), p<0.01. Among 54 Ct-concordant dyads with ompA genotype data for both members, 96.2% had identical genotypes. Conclusions Higher organism load appears associated with concordance among women. Same-genotype chlamydial concordance was high in sexual partnerships. No behavioral factors were sufficiently discriminating to guide partner services activities. Findings may help model coitus-specific transmission probabilities

Extensive genetic diversity, unique population structure and evidence of genetic exchange in the sexually transmitted parasite <i>Trichomonas vaginalis</i>

Background Trichomonas vaginalis is the causative agent of human trichomoniasis, the most common non-viral sexually transmitted infection world-wide. Despite its prevalence, little is known about the genetic diversity and population structure of this haploid parasite due to the lack of appropriate tools. The development of a panel of microsatellite makers and SNPs from mining the parasite's genome sequence has paved the way to a global analysis of the genetic structure of the pathogen and association with clinical phenotypes. Methodology/Principal Findings Here we utilize a panel of T. vaginalis-specific genetic markers to genotype 235 isolates from Mexico, Chile, India, Australia, Papua New Guinea, Italy, Africa and the United States, including 19 clinical isolates recently collected from 270 women attending New York City sexually transmitted disease clinics. Using population genetic analysis, we show that T. vaginalis is a genetically diverse parasite with a unique population structure consisting of two types present in equal proportions world-wide. Parasites belonging to the two types (type 1 and type 2) differ significantly in the rate at which they harbor the T. vaginalis virus, a dsRNA virus implicated in parasite pathogenesis, and in their sensitivity to the widely-used drug, metronidazole. We also uncover evidence of genetic exchange, indicating a sexual life-cycle of the parasite despite an absence of morphologically-distinct sexual stages. Conclusions/Significance Our study represents the first robust and comprehensive evaluation of global T. vaginalis genetic diversity and population structure. Our identification of a unique two-type structure, and the clinically relevant phenotypes associated with them, provides a new dimension for understanding T. vaginalis pathogenesis. In addition, our demonstration of the possibility of genetic exchange in the parasite has important implications for genetic research and control of the disease

Extensive Genetic Diversity, Unique Population Structure and Evidence of Genetic Exchange in the Sexually Transmitted Parasite Trichomonas vaginalis

The human parasite Trichomonas vaginalis causes trichomoniasis, the world's most common non-viral sexually transmitted infection. Research on T. vaginalis genetic diversity has been limited by a lack of appropriate genotyping tools. To address this problem, we recently published a panel of T. vaginalis-specific genetic markers; here we use these markers to genotype isolates collected from ten regions around the globe. We detect high levels of genetic diversity, infer a two-type population structure, identify clinically relevant differences between the two types, and uncover evidence of genetic exchange in what was believed to be a clonal organism. Together, these results greatly improve our understanding of the population genetics of T. vaginalis and provide insights into the possibility of genetic exchange in the parasite, with implications for the epidemiology and control of the disease. By taking into account the existence of different types and their unique characteristics, we can improve understanding of the wide range of symptoms that patients manifest and better implement appropriate drug treatment. In addition, by recognizing the possibility of genetic exchange, we are more equipped to address the growing concern of drug resistance and the mechanisms by which it may spread within parasite populations

Depressive symptoms and sexual risk behavior in young, chlamydia-infected, heterosexual dyads

Purpose: To examine associations between depressive symptoms and dyad-level sexual risk behavior in young heterosexual dyads with sexually transmitted infection (STI). Methods: Chlamydia-positive 14-24-year-old, heterosexually active outpatients and their opposite-sex partners completed an assessment that included demographics, past and recent STI risk behaviors, and the Beck Depression Inventory (BDI). Participants in the top 25% of BDI scores within gender were categorized as depressed. Variables were created to identify dyads in which the female or male partner was depressed, as well as a measure of concordance of depression between partners. Dyad-level STI risk variables were created from the STI risk characteristics reported by each dyad member, and associations between these and the depression variables were analyzed. Results: The 130 dyads were comprised of young men and women at high STI risk. One-third of dyads had at least one depressed partner. Dyads in which the female partner was depressed had greater partner age difference, greater total number of lifetime partners, and one or more partners reporting substance use within 2 hours before sex, compared with dyads in which the female partner was not depressed. Dyads in which the male partner was depressed were more likely than the nondepressed-male dyads to report substance use before sex. All dyads in which both partners were depressed reported substance use before sex. Conclusions: In young, chlamydia-infected, heterosexual dyads, depressive symptoms, especially in women, is related to increased dyad-level STI risk, including greater partner age difference, more partners, and substance use before sex