21 research outputs found
Distribution and hormonal regulation of membrane progesterone receptors β and γ in ciliated epithelial cells of mouse and human fallopian tubes
<p>Abstract</p> <p>Background</p> <p>The controlled beating of cilia of the fallopian tube plays an important role in facilitating the meeting of gametes and subsequently transporting the fertilized egg to its implantation site. Rapid effects of progesterone on ciliary beat frequency have been reported in the fallopian tubes of cows, but the identity of the receptors mediating this non-genomic action of progesterone is not known. We recently identified a member of the non-genomic membrane progesterone receptor family, mPR gamma, as a candidate for mediating these actions of progesterone. Here, we investigated the possible presence of a related receptor, mPR beta, in the fallopian tubes of mice and women as well as the possible hormonal regulation of mPR beta and gamma.</p> <p>Methods</p> <p>Western blot and immunohistochemistry with specific antibodies were used to characterize the expression and cellular localization of the mPRs in mouse and human tissues. Taqman (Quantitative Polymerase Chain Reaction) assays were used to quantify mRNA levels in the fallopian tubes of two different mouse models after injections with different hormones and specific antagonists.</p> <p>Results</p> <p>In the fallopian tubes of both mouse and human, the expression of mPR beta and mPR gamma proteins was exclusively found in the ciliated cells. Whereas mPR beta was found on the cilia, mPR gamma was localized at the base of the same ciliated cells, as previously reported. In gonadotropin-primed mice, both mPRs genes were down-regulated after an injection with progesterone. Treatment with estradiol rapidly down-regulated the level of mPR beta mRNA and protein in immature mice. The mPR gamma protein was down-regulated around the time of ovulation in cycling women, similar to the regulation observed in mice stimulated to ovulate via gonadotropin injections.</p> <p>Conclusion</p> <p>Our findings show the presence and hormonal regulation of two distinct mPRs associated with the cilia of the fallopian tubes in both mice and women. It is hypothesized that these receptors are involved in the control of ciliary movement and, thus, gamete transport in the fallopian tubes of mammals.</p
Pyrosequencing of Antibiotic-Contaminated River Sediments Reveals High Levels of Resistance and Gene Transfer Elements
The high and sometimes inappropriate use of antibiotics has accelerated the development of antibiotic resistance, creating a major challenge for the sustainable treatment of infections world-wide. Bacterial communities often respond to antibiotic selection pressure by acquiring resistance genes, i.e. mobile genetic elements that can be shared horizontally between species. Environmental microbial communities maintain diverse collections of resistance genes, which can be mobilized into pathogenic bacteria. Recently, exceptional environmental releases of antibiotics have been documented, but the effects on the promotion of resistance genes and the potential for horizontal gene transfer have yet received limited attention. In this study, we have used culture-independent shotgun metagenomics to investigate microbial communities in river sediments exposed to waste water from the production of antibiotics in India. Our analysis identified very high levels of several classes of resistance genes as well as elements for horizontal gene transfer, including integrons, transposons and plasmids. In addition, two abundant previously uncharacterized resistance plasmids were identified. The results suggest that antibiotic contamination plays a role in the promotion of resistance genes and their mobilization from environmental microbes to other species and eventually to human pathogens. The entire life-cycle of antibiotic substances, both before, under and after usage, should therefore be considered to fully evaluate their role in the promotion of resistance
Survival of Donor-Derived Cells in Human Corneal Transplants
PURPOSE. To determine the fate of donor epithelial, stromal, and endothelial cells after corneal transplantation in humans. METHODS. Fifty-two transplanted corneal buttons were explanted over a 2-year period from patients who required regrafting and had received corneas from donors of opposite sex. Fluorescence in situ hybridization of the sex chromosomes of the epithelial, stromal, and endothelial cells was performed in histologic sections prepared from each freshly explanted graft. Fluorescence microscopy was subsequently used to determine the origin of cells in the graft (donor or recipient) and to quantify the relative proportion of donor and recipient cells of each corneal cell type. RESULTS. As early as 3 months after transplantation, donor epithelial cells were completely replaced by recipient epithelium in all corneal buttons examined. Donor stromal and endothelial cells, however, were found in all 52 buttons, with 4% to 95% of stromal cells and 6% to 95% of endothelial cells being of donor origin. No significant correlation between donor cell proportion and the age of the graft could be found. Donorderived cells were found in significant numbers up to 32 years after transplantation. Eight corneas in this study were transparent, compensated grafts, and a similar long-term survival of donor stromal and endothelial cells was found in these cases. CONCLUSIONS. Although donor epithelial cells are promptly replaced, a high proportion of donor stromal and endothelial cells can survive within the corneal transplant in the long-term. The proportion of surviving donor cells is highly variable; however, the source of this variability remains unknown. (Invest Ophthalmol Vis Sci
Dynamic regulation of estrogen receptor-α isoform expression in the mouse fallopian tube: mechanistic insight into estrogen-dependent production and secretion of insulin-like growth factors
The Regulation of Nitric Oxide Synthase Isoform Expression in Mouse and Human Fallopian Tubes: Potential Insights for Ectopic Pregnancy
Nitric oxide (NO) is highly unstable and has a half-life of seconds in buffer solutions. It is synthesized by NO-synthase (NOS), which has been found to exist in the following three isoforms: neuro nitric oxide synthase (nNOS), inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS). NOS activity is localized in the reproductive tracts of many species, although direct evidence for NOS isoforms in the Fallopian tubes of mice is still lacking. In the present study, we investigated the expression and regulation of NOS isoforms in the mouse and human Fallopian tubes during the estrous and menstrual cycles, respectively. We also measured isoform expression in humans with ectopic pregnancy and in mice treated with lipopolysaccharide (LPS). Our results confirmed the presence of different NOS isoforms in the mouse and human Fallopian tubes during different stages of the estrous and menstrual cycles and showed that iNOS expression increased in the Fallopian tubes of women with ectopic pregnancy and in LPS-treated mice. Elevated iNOS activity might influence ovulation, cilia beats, contractility, and embryo transportation in such a manner as to increase the risk of ectopic pregnancy. This study has provided morphological and molecular evidence that NOS isoforms are present and active in the human and mouse Fallopian tubes and suggests that iNOS might play an important role in both the reproductive cycle and infection-induced ectopic pregnancies
Differences in Prolactin Receptor (PRLR) in Mouse and Human Fallopian Tubes: Evidence for Multiple Regulatory Mechanisms Controlling PRLR Isoform Expression in Mice1
The O-Linked Glycome and Blood Group Antigens ABO on Mucin-Type Glycoproteins in Mucinous and Serous Epithelial Ovarian Tumors.
Mucins are heavily O-glycosylated proteins where the glycosylation has been shown to play an important role in cancer. Normal epithelial ovarian cells do not express secreted mucins, but their abnormal expression has previously been described in epithelial ovarian cancer and may relate to tumor formation and progression. The cyst fluids were shown to be a rich source for acidic glycoproteins. The study of these proteins can potentially lead to the identification of more effective biomarkers for ovarian cancer.In this study, we analyzed the expression of the MUC5AC and the O-glycosylation of acidic glycoproteins secreted into ovarian cyst fluids. The samples were obtained from patients with serous and mucinous ovarian tumors of different stages (benign, borderline, malignant) and grades. The O-linked oligosaccharides were released and analyzed by negative-ion graphitized carbon Liquid Chromatography (LC) coupled to Electrospray Ionization tandem Mass Spectrometry (ESI-MSn). The LC-ESI-MSn of the oligosaccharides from ovarian cyst fluids displayed differences in expression of fucose containing structures such as blood group ABO antigens and Lewis-type epitopes.The obtained data showed that serous and mucinous benign adenomas, mucinous low malignant potential carcinomas (LMPs, borderline) and mucinous low-grade carcinomas have a high level of blood groups and Lewis type epitopes. In contrast, this type of fucosylated structures were low abundant in the high-grade mucinous carcinomas or in serous carcinomas. In addition, the ovarian tumors that showed a high level of expression of blood group antigens also revealed a strong reactivity towards the MUC5AC antibody. To visualize the differences between serous and mucinous ovarian tumors based on the O-glycosylation, a hierarchical cluster analysis was performed using mass spectrometry average compositions (MSAC).Mucinous benign and LMPs along with mucinous low-grade carcinomas appear to be different from serous and high-grade mucinous carcinomas based on their O-glycan profiles