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21.
The expression of a 70 kDa chaperone protein, HspA2 (formerly called CK-M), has been identified in mature human spermatozoa. The central role of HspA2 has been established, as the expression level of this protein is related to sperm cellular maturity, DNA integrity, chromatin maturity, chromosomal aneuploidy frequency and sperm function, including fertilizing potential. The spermiogenetic events of cytoplasmic extrusion and remodelling of the plasma membrane, which facilitate the formation of zona pellucida binding site(s) in human spermatozoa, are related. Finally, the presence of the hyaluronic acid (HA) receptor on the plasma membrane of mature sperm coupled with the HA-coated slide sperm-binding assay, facilitates the testing of infertile men and the selection of single mature spermatozoa for ICSI. Because mature spermatozoa have no residual cytoplasm, the HA-bound sperm fraction is also enriched in spermatozoa that are normal by the Kruger strict morphology method.  相似文献   
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OBJECTIVE: To determine the changes in cyclooxygenase-2 (COX-2), E-cadherin and alpha-catenin expression after partial bladder outlet obstruction (PBOO), and whether a selective COX-2 inhibitor (celecoxib) might inhibit COX-2 expression and have beneficial effects on urothelial cell-to-cell interactions in rats subjected to PBOO. MATERIALS AND METHODS: Thirty-six male rats were divided into six equal groups; celecoxib was administered after creating PBOO for 1 and 4 weeks in groups 1 and 2, respectively. Two further obstructed groups (3 and 4, PBOO for 1 and 4 weeks, respectively) received no treatment. Sham-operated animals served as controls (group 5 and 6, assessed at 1 and 4 weeks, respectively). After 1 and 4 weeks of PBOO or a sham procedure the bladder weight was recorded before sampling the bladder for Western blotting and immunohistological analysis, to assess the expressions of COX-2 and adherens proteins, E-cadherin and alpha-catenin. Urothelial cell-to-cell interactions were evaluated using electron microscopy. RESULTS: The bladder mass increased rapidly during the first 7 days after PBOO in groups 1-4 compared with 5 and 6 (P < 0.05). While the bladder mass then continued to increase for the next 21 days in group 4, it was constant in group 2 (P < 0.001). Immunohistochemical staining and Western blotting analyses showed that E-cadherin and alpha-catenin expression were reversibly decreased in rats with PBOO, while COX-2 protein expression was up-regulated. After giving celecoxib there was a significant decrease in COX-2 expression and a restoration of intercellular adherens junctions and desmosomes, as assessed on electron microscopy and expression of adherens proteins combined. CONCLUSION: The increase in COX-2 expression attributable to hypoxia and the tensile strength of bladder wall was attenuated by celecoxib. Selective COX-2 inhibitors have important restorative effects on intercellular adherens junctions and desmosomes in PBOO.  相似文献   
24.
Pediculosis capitis is a worldwide problem and a growing concern because of resistance to pediculicides. In the present study, we investigated whether albendazole could be used in the treatment of pediculosis capitis in combination with 1% permethrin or alone. A total of 150 children were randomly divided to five groups of 30 each. Group 1 got albendazole in a single dose (400 mg), group 2 got albendazole at 400 mg for 3 days, group 3 was given 1% permethrin, group 4 took 1% permethrin and albendazole in a single dose (400 mg), and group 5 got 1% permethrin and albendazole in a dose of 400 mg for 3 days. Groups given albendazole were also given another 400 mg dose of albendazole after 1 week. The success rate of treatment at the 2-week follow-up for all groups was 61.5%, 66.6%, 80.0%, 84.6%, and 82.1%, respectively. No statistically significant difference was found between the groups. The results of this study suggest that albendazole is effective against pediculosis capitis and there is no synergistic effect between albendazole and 1% permethrin.  相似文献   
25.
BackgroundDoxorubicin (DOX), is a chemotherapeutic agent, which evokes oxidative stress and cell apoptosis in testicular tissue. It is known that the activation of the nuclear enzyme poly (ADP-ribose) polymerase (PARP), leading to apoptosis induced by DOX. The aim of the present study is to investigate whether PARP pathway has a role in DOX-induced testicular damage and infertility utilizing pharmacological PARP-1 inhibitor, PJ34, and PARP-1 knockout mice model.MethodsFirstly, we assessed the activation of PARP pathway after DOX-induction at various hours by immunohistochemistry and western blot analysis. Secondly, we evaluated the role of PARP pathway in DOX-induced testicular damage, sperm motility, and fertility with pharmacological inhibition of PARP by using PJ34. Finally, we aimed to correlate a functional relationship between PARP-1 and DOX using PARP-1 knockout mice in DOX-induced testicular damage. Doxorubicin levels in plasma and testis tissue were also assessed.ResultsIn DOX-induced group; PARP-1, PAR and apoptotic pathway protein expressions, increased significantly. In DOX + PJ34 group; PAR, cytochrome c, and AIF levels decreased significantly. Testicular weights, sperm motility, and mean the number of pups per litter decreased in DOX-induced group after 28 days, however they were similar to the control group in DOX-PJ34 group. In PARP-1 KO group, seminiferous tubule morphology was impaired significantly after 28 days of DOX-administration.ConclusionsOur study indicates that DOX-induced testicular damage may be related to over-activation of PARP-1. PJ34 application was effective in preventing severe testicular damage caused by DOX-injection and may be considered for fertility protection against DOX-induced testicular damage.  相似文献   
26.
Journal of Assisted Reproduction and Genetics - This study aims to investigate whether indomethacin (IND) delays preterm birth by regulating the Notch pathway, Tlr receptors, and Sp-A in the...  相似文献   
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Despite the known adverse effects of abamectin pesticide, little is known about its action on male fertility. To explore the effects of exposure to abamectin on male fertility and its mechanism, low (1 mg/kg/day) and high dose (4 mg/kg/day) abamectin were applied to male rats by oral gavage for 1 week and for 6 weeks. Weight of testes, serum reproductive hormone levels, sperm dynamics and histopathology of testes were used to evaluate the reproductive efficiency of abamectin-exposed rats. Abamectin level was determined at high concentrations in plasma and testicular tissues of male rats exposed to this pesticide. The testes weights of animals and serum testosterone concentrations did not show any significant changes after abamectin exposure. Abamectin administration was associated with decreased sperm count and motility and increased seminiferous tubule damage. In addition, significant elevations in the 4-hydroxy-2-nonenal (4-HNE)-modified proteins and poly(ADP-ribose) (PAR) expression, as markers for oxidative stress and poly(ADP-ribose) polymerase (PARP) activation, were observed in testes of rats exposed to abamectin. These results showed that abamectin exposure induces testicular damage and affects sperm dynamics. Oxidative stress-mediated PARP activation might be one of the possible mechanism(s) underlying testicular damage induced by abamectin.  相似文献   
28.
Purpose: To compare the antioxidant status of three cord clamping procedures (early clamping, delayed clamping and milking) by analyzing the thiol–disulfide balance.

Patients and methods: This randomized controlled study enrolled 189 term infants who were divided into three groups according to the cord clamping procedure: early clamping, delayed clamping and milking. Blood samples were collected from the umbilical arteries immediately after clamping, and the thiol/disulfide homeostasis was analyzed.

Results: The native and total thiol levels were significantly (p?p?=?.026) lower in the delayed cord clamping and milking groups compared with the early clamping groups. Early cord clamping causes the production of more disulfide bonds and lower thiol levels, indicating that oxidation reactions are increased in the early cord clamping procedure compared with the delayed cord clamping and milking procedures.

Conclusion: The oxidant capacity is greater with early cord clamping than with delayed clamping or cord milking. Delayed cord clamping or milking are beneficial in neonatal care, and we suggest that they be performed routinely in all deliveries.  相似文献   
29.
The presence of progenitor/stem cells in human articular cartilage remains controversial. Therefore, we attempted to isolate and culture progenitor/stem cells and to investigate their phenotypic characteristics. Biopsies were obtained (with consent) from patients undergoing arthroscopic surgery. Full depth explants were fixed and cryosectioned or enzymatically digested and the resulting cells cultured and plated on fibronectin-coated dishes. Chondrocytes were cultured until colonies of >32 cells were present. Colonies were trypsinized and expanded in monolayer for pellet culture. Immunolocalization of Notch and its ligands were detected in vivo and in vitro using immunocytochemistry. In vitro studies investigated differences in immunolocalization of Notch and its associated ligands in colony-forming cells and small clusters of non-colony-forming cells. The ultrastructure of the chondroprogenitors was examined by scanning and transmission electron microscopy. Results revealed that the immunolocalization of Notch-1 and its ligand Delta were concentrated in regions closest to the articular surface. Notch-1 was also densely localized in the deeper zone of articular cartilage. Notch-2 immunolabeling was densely localized in all zones of articular cartilage. Jagged-1 was concentrated in the deeper regions of articular cartilage. Notch-1, Delta and Jagged-1 were more abundant in colony-forming cells than non-colony-forming chondrocytes in vitro. Notch-3, Notch-4 and Jagged-2 were absent from all regions of the articular cartilage tissues and cultured cartilage cells in vitro. Ultrastructurally, chondrocytes cultured in monolayer dedifferentiated to fibroblast-like cells with cell surface processes of varying lengths, pellet cultured cells varied in morphology, as flattened and rounded. In conclusion, we propose that adult human articular cartilage may contain cells having progenitor cell features.  相似文献   
30.
This study was aimed to examine the effect of chronic taurine treatment on corpus cavernosum dysfunction in diabetic rats and to investigate possible underlying mechanisms. Thirty male rats were randomized to three groups of 10 each, including control, diabetic, and taurine‐treated diabetic. Diabetes was induced in rats by streptozotocin (STZ, single intraperitoneal dose of 50 mg/kg body weight). Taurine was administered orally for 12 weeks (1% w/v in drinking water) from the day on which STZ was injected. At the end of the 12th week, strips of corpus cavernosum were suspended in an organ bath system for functional studies. Nitric oxide (NO)‐mediated endothelium‐dependent and neurogenic corpus cavernosum relaxation were evaluated by acetylcholine (ACh, 0.1–100 μm ) and electrical field stimulation (EFS, 30 V, 5 ms, 2–32 Hz), respectively. The expressions of endothelial nitric oxide synthase (eNOS), phosphorylated eNOS (p‐eNOS) (Ser‐1177), neuronal nitric oxide synthase (nNOS), NADPH oxidase subunit gp91phox, Rho A, and Rho kinase in corpus cavernosum were semi‐quantitatively assessed by immunohistochemistry. Induction of diabetes resulted in significant inhibition of NO‐mediated endothelium‐dependent and neurogenic corpus cavernosum relaxation. Furthermore, eNOS, p‐eNOS, and nNOS expressions decreased significantly in diabetic rats compared to controls, while gp91phox, RhoA and Rho kinase expressions increased significantly. The diminished relaxation response to ACh and EFS as well as diabetes‐related changes in expressions of these proteins in corpus cavernosum of diabetic rats was significantly improved by taurine. Taurine treatment improves NO‐mediated relaxations of corpus cavernosum in diabetic rats probably by inhibiting NADPH oxidase/Rho kinase pathways.  相似文献   
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