Mesenchymal cell precursors of peritubular smooth muscle cells of the mouse testis can be identified by the presence of the p75 neurotrophin receptor. (33/381)

In the mouse embryo, at approximately 11.5 days postcoitum (dpc), cells migrate from the mesonephros into the developing testis to contribute to the somatic population of the interstitial compartment (i.e., peritubular myoid cells, Leydig cells, and endothelial cells). Studies from this laboratory have shown that the interstitial population of mesenchymal cells in fetal and newborn mouse testis express the p75 neurotrophin receptor (p75NTR, formerly known as the low-affinity nerve growth factor receptor); part of the cell population progressively congregates around testis cords, later to be replaced by contractile peritubular myoid cells, which express smooth muscle cell markers. In the present study, we show that the migrating cells and the p75NTR-expressing cells are the same population. We also show that the neurotrophin receptor is a useful endogenous marker to follow cell migration within the urogenital ridge and to identify and isolate mesenchymal precursors of myoid cells. A time-course immunolocalization study of the location of p75NTR-bearing cells within the urogenital ridge of mouse embryos between 10.5 and 12.5 dpc showed that the interstitium of the fetal testis was progressively occupied by p75NTR+ cells. The progressive increase of p75NTR expression within the developing testis was confirmed by immunoblot analysis of proteins isolated from the fetal gonads. Organ cultures of isolated testes or testis-mesonephros grafts confirmed that p75NTR+ cells do not appear in the testis unless a mesonephros is attached to it. Cells bearing the p75NTR receptor, purified from 12.5-dpc male mouse mesonephroi by immunomagnetic sorting, were able to differentiate in vitro into myoid cells. Immunofluorescence analysis of postnatal testis sections confirmed the presence around the tubules of cells coexpressing p75NTR and alpha-smooth muscle actin. The ability to identify and purify precursors of myoid cells may be of considerable help for studying the mechanisms regulating their differentiation.  (+info)

Safety and tolerability of BufferGel, a novel vaginal microbicide, in women in the United States. (34/381)

BufferGel (ReProtect, LLC) is a vaginal gel with an acidic buffering action that was designed to prevent vaginal neutralization by semen. The purpose of this study was to evaluate the safety and tolerability of BufferGel (ReProtect, Limited Liability Company) applied vaginally either once or twice daily by 27 women who were at low risk for acquisition of human immunodeficiency virus (HIV). Participants initially used the product once daily for 14 days and then twice daily for 14 days; they underwent colposcopy before and after product exposure. BufferGel was well tolerated, although two-thirds of the participants reported at least 1 mild or moderate adverse experience. The most common adverse events were irritative genitourinary symptoms. Product use was discontinued after 3 adverse events. BufferGel was well tolerated in women at low risk for acquisition of HIV; toxicity was limited and occurred at frequencies similar to those in women who did not use any vaginal product and at levels lower than in women who used detergent-based microbicides.  (+info)

Inflammation and clearance of Chlamydia trachomatis in enteric and nonenteric mucosae. (35/381)

Immunization(s) fostering the induction of genital mucosa-targeted immune effectors is the goal of vaccines against sexually transmitted diseases. However, it is uncertain whether vaccine administration should be based on the current assumptions about the common mucosal immune system. We investigated the relationship between mucosal sites of infection, infection-induced inflammation, and immune-mediated bacterial clearance in mice using the epitheliotropic pathogen Chlamydia trachomatis. Chlamydial infection of the conjunctival, pulmonary, or genital mucosae stimulated significant changes in tissue architecture with dramatic up-regulation of the vascular addressin, VCAM, a vigorous mixed-cell inflammatory response with an influx of alpha4beta1+ T cells, and clearance of bacteria within 30 days. Conversely, intestinal mucosa infection was physiologically inapparent, with no change in expression of the local MAdCAM addressin, no VCAM induction, no histologically detectable inflammation, and no tissue pathology. Microbial clearance was complete within 60 days in the small intestine but bacterial titers remained at high levels for at least 8 months in the large intestine. These findings are compatible with the notion that VCAM plays a functional role in recruiting cells to inflammatory foci, and its absence from the intestinal mucosa contributes to immunologic homeostasis at that site. Also, expression of type 1 T cell-mediated immunity to intracellular Chlamydia may exhibit tissue-specific variation, with the rate and possibly the mechanism(s) of clearance differing between enteric and nonenteric mucosae. The implications of these data for the common mucosal immune system and the delivery of vaccines against mucosal pathogens are discussed.  (+info)

Tissue engineering applications in the genitourinary tract system. (36/381)

The concept of cell transplantation using tissue engineering techniques has provided numerous possibilities in the area of urologic tissue reconstruction. Tissue engineering applications in the genitourinary tract system have been investigated in almost every tissue in order to improve, restore and replace existing tissue function. Although most reconstructive efforts still remain in the experimental stage, several technologies have been transferred to the bedside with satisfactory outcome. In this article, we describe tissue engineering approaches attempted in the genitourinary system for reconstruction.  (+info)

Experimental administration of estradiol on the colonization of lactobacillus fermentum and escherichia coli in the urogenital tract of mice. (37/381)

The effect of estrogen on the microbial colonization of the urogenital tract is widely discussed, mainly in regard to women with a high incidence of Urinary Tract Infections (UTI). The aim of this work was to study the effect of estradiol on the microbial colonization of lactobacilli and E. coli in mice. Female BALB/c mice were intramuscularly (i.m.) treated with beta-estradiol (one or three doses). The next day, L. fermentum was inoculated intraurethrally with three doses of 10(7) CFU (Colony Forming Units). Later, mice were challenged with uropathogenic E. coli (1 x 10(8) CFU). The hormone levels in sera increased to values 10 times higher than in control animals. Increased differentiation of desquamated vaginal cells and keratinization of the vaginal surface were also observed. The hormonal treatment produced an increased E. coli colonization in the whole tract and a higher level of L. fermentum in kidneys on the 6th day. In mice treated with hormones and lactobacilli, one dose of estradiol was enough to protect animals against the challenge with E. coli. Three doses of estradiol produced a more pronounced protection with a lower number of E. coli. No histological modifications were produced by L.fermentum, while lymphocytic proliferation at submucosal level was observed in E. coli-challenged animals.  (+info)

Selective expression of murine prostate stem cell antigen in fetal and adult tissues and the transgenic adenocarcinoma of the mouse prostate model of prostate carcinogenesis. (38/381)

Prostate stem cell antigen (PSCA) is a GPI-anchored membrane protein whose expression is reportedly up-regulated in a majority of human prostate cancers, including advanced stages and metastases. In this study, we investigate the expression pattern of the murine orthologue of PSCA by in situ hybridization in fetal and adult mouse tissues. Murine PSCA is expressed during fetal development in the urogenital sinus, skin, and gastrointestinal tract. The expression in these tissues is restricted to the most superficial cell layer. In the adult mouse, expression is highest in the mucosal lining of the urinary tract. In the normal adult prostate, expression of PSCA is detected exclusively in the secretory epithelium. Examination of PSCA during carcinogenesis of the murine prostate in the transgenic adenocarcinoma of the mouse prostate model showed a markedly increased expression in areas of neoplasia. The transgenic adenocarcinoma of the mouse prostate model may represent a valuable model for the study of PSCA as a potential target for immunotherapy of prostate cancer, despite potential differences in the pattern of expression between mice and humans.  (+info)

Cross-species and interassay comparisons of phytoestrogen action. (39/381)

This paper compiles animal and human data on the biologic effects and exposure levels of phytoestrogens in order to identify areas of research in which direct species comparisons can be made. In vitro and in vivo assays of phytoestrogen action and potency are reviewed and compared to actions, dose-response relationships, and estimates of exposure in human subjects. Binding studies show that the isoflavonoid phytoestrogens are high-affinity ligands for estrogen receptors (ERs), especially ER beta, but have lower potency in whole-cell assays, perhaps because of interactions with binding proteins. Many other enzymatic actions require concentrations higher than those normally seen in plasma. In vivo data show that phytoestrogens have a wide range of biologic effects at doses and plasma concentrations seen with normal human diets. Significant in vivoresponses have been observed in animal and human tests for bone, breast, ovary, pituitary, vasculature, prostate, and serum lipids. The doses reported to be biologically active in humans (0.4--10 mg/kg body weight/day) are lower than the doses generally reported to be active in rodents (10--100 mg/kg body weight/day), although some studies have reported rodent responses at lower doses. However, available estimates of bioavailability and peak plasma levels in rodents and humans are more similar. Steroidogenesis and the hypothalamic-pituitary-gonadal axis appear to be important loci of phytoestrogen actions, but these inferences must be tentative because good dose-response data are not available for many end points. The similarity of reported proliferative and antiproliferative doses illustrates the need for fuller examination of dose-response relationships and multiple end points in assessing phytoestrogen actions.  (+info)

Enzyme immunoassay for urogenital trichomoniasis as a marker of unsafe sexual behaviour. (40/381)

Enzyme immunoassay (EIA) was used to detect antibodies to Trichomonas vaginalis in sera from Zimbabwe. The EIA showed a sensitivity of 95 and 94% when compared with vaginal swab culture among women attending a family planning clinic (FPC) and female commercial sex workers (CSW) respectively. The specificity was 85 and 77% in the two groups. Culture-negative FPC women were sub-divided into high risk or low risk of exposure to trichomoniasis. The seroprevalence was 10% (6/61) among low risk women, 21% (10/48) among high risk women and 23% (9/39) among culture negative CSW. The EIA was positive in 46% (18/39) men with genital discharge but only 5% (2/37) healthy blood donors. None of 31 sera from prepubescent children was positive. The EIA may be useful for community surveys of trichomoniasis. Because T. vaginalis is a common sexually transmitted disease, the test may indicate behaviour that increases the risk of STD transmission.  (+info)