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21.
卵巢癌是妇科常见的恶性肿瘤,其死亡率居妇科恶性肿瘤之首,早期发现有助于提高患者的五年生存率。人附睾蛋白(HE4)属于蛋白酶抑制剂家族,是一种新的卵巢癌肿瘤标志物。HE4在卵巢癌组织中及患者血清中处于高表达状态。研究表明在早期诊断方面HE4比糖类抗原125(CA125)有更高的灵敏度和特异度,在疾病的治疗过程中可以预测肿瘤细胞减灭术的满意度及患者对铂类的反应,在卵巢癌的复发及预后的监测中HE4也有很大的临床应用价值。  相似文献   
22.
Mammalian spermatozoa acquire functionality during epididymal maturation and ability to penetrate and fertilize the oocyte during capacitation. The aim of this study was to investigate the impact of epididymal maturation, ejaculation and capacitation on phosphotyrosine content of sperm proteins. Western blot, immunocytochemical and flow cytometry analyses demonstrated that epididymal maturation in vivo is associated with a progressive loss of phosphotyrosine residues of the sperm head followed by a subtle increase after in vitro capacitation. As cells pass from caput to cauda epididymis, tyrosine phosphorylation becomes confined to a triangular band over the posterior part of midacrosome region, whereas in vitro capacitation causes a spread labeling over the whole head. Different bands with phosphotyrosine residues were detected during epididymal maturation and after in vitro capacitation: 1) 93, 66 and 45 kDa bands with specific phosphotyrosine expression in immature spermatozoa; 2) 76, 23 and 12 kDa bands with specific phosphotyrosine expression in mature spermatozoa, being significantly increased in their expression after in vitro capacitation; 3) 49, 40, 37, 30, 26 and 25 kDa constitutive bands that increased their phosphotyrosine expression after maturation and/or in vitro capacitation; and 4) 28 and 20 kDa bands with a specific phosphotyrosine expression in in vitro capacitated spermatozoa. These results provided integral novel data of expression and location of phosphotyrosine residues during epididymal maturation, ejaculation and in vitro capacitation of boar spermatozoa. Two new constitutive proteins bands of 26 and 25 kDa with phosphotyrosine residues were also identified.  相似文献   
23.
Treatment‐induced epididymal inflammation and granuloma formation is only an occasional problem in preclinical drug development, but it can effectively terminate the development of that candidate molecule. Screening for backup molecules without that toxicity must be performed in animals (generally rats) that requires at least 2 to 3 weeks of in vivo exposure, a great deal of specially synthesized candidate compound, and histologic examination of the target tissues. We instead hypothesized that these treatments induced proinflammatory gene expression, and so used mixed‐cell cultures from the rat epididymal tubule to monitor the induction of proinflammatory cytokines. Cells were exposed for 24 hr and then cytotoxicity was evaluated with the MTS assay and mRNA levels of Interleukin‐6 (IL‐6) and growth‐related oncogene (GRO) were measured. We found that compounds that were more toxic in vivo stimulated a greater induction of IL‐6 and GRO mRNA levels in vitro. By relating effective concentrations in vitro with the predicted Ceff, we could rank compounds by their propensity to induce inflammation in rats in vivo. This method allowed the identification of several compounds with very low inflammatory induction in vitro. When tested in rats, the compounds produced small degrees of inflammation at an acceptable margin (approximately 20×), and have progressed into further development  相似文献   
24.
The aim of this study was to investigate the possible prophylactic effects of agomelatine (AGO) against testicular and epididymal damage induced by methotrexate (MTX) in rats. Twenty‐four male Wistar albino rats were divided into three groups: Group I (control group), Group II (MTX group: 20 mg/kg MTX, i.p, single dose), and Group III (MTX+AGO group: 20 mg/kg MTX, i.p, single dose+40 mg/kg AGO; gavage, 7 days). The rats were killed under anesthesia 24 hours after the last AGO application. Testicular and epididymal tissues were bilaterally removed for morphometric, biochemical, pathological, and immunohistochemical analyses. Body, testicular, and epididymal weights were measured. Malondialdehyde (MDA), superoxide dismutase, catalase, and glutathione peroxidase levels were measured in testes. Sperm count, hyperemia, edema, inflammatory reaction, degenerated and necrotic cells were evaluated by histopathological analysis. In addition, inducible nitric oxide synthase (iNOS), granulocyte colony‐stimulating factor (G‐CSF), osteopontin (OPN), and heat shock protein‐70 (HSP70) immune reactions were analyzed in testes and epididymides. Decreased epididymal weights, increased MDA levels, decreased sperm count, hyperemia, edema, inflammatory reaction, and degenerated and necrotic cells were observed in the MTX group. In addition, iNOS, HSP70, G‐CSF, and OPN immune reactions were increased. AGO improved morphometric, biochemical, histopathological, and immunohistochemical findings. The present study confirms that MTX induces testicular and epididymal damage both biochemically and immunohistochemically. However, AGO demonstrated ameliorative effects on both biochemical and pathological findings of the current study.  相似文献   
25.
The time required for passage of spermatozoa through the epididymis has been determined in hamster employing quantitative light microscopic autoradiography with 3H-thymidine. The time required for spermatozoa to traverse the caput is 3 days; corpus, 2 days; proximal cauda, 2 days; distal cauda, 6 days. An additional 2 days are required for passage of spermatozoa through the proximal ductus deferens. The total duration of sperm transit through the ductus epididymis in sexually rested hamster has been estimated at about 15.0 days.  相似文献   
26.
The genetics of esterase-28, the major esterase of cauda epididymidis of the house mouse, has been studied after separation by polyacrylamide gel electrophoresis and isoelectric focusing. Four phenotypes are distinguished. Segregation ofEs-28 in two backcross series indicated linkage to Es-1, Es-9, and Es-22. The Es-28 locus was placed into esterase cluster 1 on chromosome 8.This work was supported by the Deutsche Forschungsgemeinschaft.This is communication No. 69 of a research program devoted to the cellular distribution, genetics, and regulation of nonspecific esterases.  相似文献   
27.
Summary Interpretation of the experimental literature on epididymal glycerophosphorylcholine metabolism according to a recently proposed de novo pathway for the synthesis of acyl-specific phosphatidylcholine suggests that epididymal glycerophosphorylcholine is an intermediate of this proposed pathway. This glycerophosphodiester is postulated to be utilized by spermatozoa to synthesize docosahexaenoic phosphatidylcholine, proposed to be required for the development of sperm motility. A defect in glycerophosphorylcholine synthesis might be responsible for some forms of asthenozoospermia.  相似文献   
28.
The bat Corynorhinus mexicanus provides an interesting experimental model for the study of epididymal sperm maturation because after spermatogenesis and the regression of the testes, this bat stores sperm in the epididymal cauda for several months. Earlier research conducted by our group suggested that sperm maturation in this species must be completed in the caudal region of the epididymis. One of the major signal transduction events during sperm maturation is the tyrosine phosphorylation of sperm proteins. The aim of the present study was to comparatively evaluate tyrosine phosphorylation in spermatozoa obtained from the caput, corpus and cauda of the epididymis during the sperm storage period. The maturation status of the sperm was determined by the percentage of capacitation and tyrosine phosphorylation in sperm obtained from the epididymis. The highest proportion of tyrosine phosphorylation was registered after the sperm had reached the cauda epididymis during the middle of the storage period. In conclusion, in Corynorhinus mexicanus and most likely in other chiropteran species with an asynchronous male reproductive pattern, epididymal sperm maturation ends in the caudal region of the epididymis and is related to the time that the sperm remains in the epididymis before mating activity.  相似文献   
29.
Seasonal changes in epididymal weight and histology were studied in relation to testicular function in the adult spiny-tailed lizard, Uromastix hardwicki, over a period of 1 year. The eipdidymal weights, tubular diameter, and epithelial height increased in March, reaching a peak in April. This peak coincided with sperm maturation, elevated plasma testosterone levels, and release of sperm into the epididymis. The epididymal weights decreased in May following a sudden regression of the testis early in the month. The epididymal weights decreased further during June and remained low until February. The diameter of the duct and the height of the epithelial cells also decreased in May and the epididymal epithelium maintained a low histological profile from June to February. The fall testicular recrudescence was not accompanied by a change either in the weight or the histological structure of the epididymis. Administration of oFSH (0.1 mg) daily for 7 days during the sexually quiescent period induced a significant increase in the weight of the epididymis and epithelial height of the duct. Administration of testosterone alone, (2.0 mg) daily for the same period and under identical conditions, did not induce a change in the weight of epididymis or its histology. A possible permissive role of gonadotrophin in the hormonal regulation of the lizard epididymis has been suggested.  相似文献   
30.
Lectins have been used to analyze variations in the distribution and density of exposed saccharides of the sperm plasma membrane during physiologic maturation and after ejaculation. Studies have been conducted in a number of nonprimate species but have been conducted to only a limited extent in nonhuman primates. In this study, pure suspensions of chimpanzee sperm from the caput and cauda epididymis and from the ejaculate were labeled with lectins conjugated to fluorescein isothiocyanate in order to visualize changes in the distribution of exposed membrane glycocomponents. The lectins used were Con A, DBA, RCA-I, and WGA. Con A binding showed minimal change during epididymal transit, with an increased binding to the flagellum after ejaculation. DBA binding was relatively constant in all specimens. RCA-I showed distinct changes in binding pattern between epididymal and ejaculated sperm. On ejaculated sperm strong fluorescence was limited to the posterior head and to the midpiece. WGA binding increased during epididymal passage and decreased after ejaculation. There appears to be a wide variety of saccharide groups available for lectin binding on the surface of epididymal and ejaculated chimpanzee sperm. The general similarity in binding patterns of caput and cauda epididymal chimpanzee sperm exposed to Con A and DBA might reflect the fact that sperm morphology does not change during epididymal transit in this species, thus implying a more stable membrane structure than is present in other primates so far studied.  相似文献   
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