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Abstract

Cadmium (Cd) as environmental pollutant can induce severe damage, particularly to the testis. This study investigated the effects of Caffeic acid phenethyl ester (CAPE) on testicular dysfunction induced by Cd. Adult mice were intraperitoneally injected with cadmium chloride (CdCl2) with different doses of CAPE pretreatment. After CdCl2 injection, body/testis weight ratio decreased, Cd levels accumulated and zinc levels decreased in testis. Furthermore, Cd intoxication caused a significant increase of oxidative stress levels, antioxidant enzymes activities, and glutathione levels. Interestingly, significant improvements were observed after the administration of CAPE. Our results demonstrated the protective effect of CAPE, linking Cd testicular dysfunction to oxidative stress.  相似文献   
3.
Reactive oxygen species and human spermatozoa: physiology and pathology   总被引:20,自引:1,他引:19  
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial.  相似文献   
4.
7例睾丸静脉和2例卵巢静脉变异的解剖学研究   总被引:2,自引:0,他引:2  
目的:了解睾丸静脉和卵巢静脉的变异。方法:观测了73具(146侧)成人尸体(男58,女15)两种静脉的形态结构。结果:发现两种静脉有变异者7例,其中睾丸静脉5例,卵巢静脉2例,另外,作者还对变异与国内文献作了比较。结论:本研究为探讨睾丸静脉和卵巢静脉曲张发生原因及治疗等提供解剖学资料。  相似文献   
5.
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality.  相似文献   
6.
An antiserum to the purified porcine outer acrosomal membrane (OAM) was raised in female Balb/c mice and was characterized by means of an indirect ELISA. The hyperimmune serum reacted selectively with the acrosomal cap of the sperm head and showed an extremely good cross reactivity with bull and human spermatozoa when assayed by indirect immunofluorescence. Immunoelectron microscopy using the protein A-gold method further confirmed the specificity of the anti-OAM-antiserum for the OAM. In an effort to identify the OAM antigens recognized by the hyperimmune serum and to analyse the extent of cross reactivity on a molecular level, the SDS-extractable proteins were separated by SDS-PAGE, transblotted and immunoprinted using an 125J-conjugated anti-mouse-antibody. To facilitate functional and structural analysis of distinct OAM-proteins monoclonal antibodies were generated by hybridization of mouse myeloma cells with the splenocytes of female Balb/c mice immunized with the purified OAM. One fusion resulted in about 100 anti-OAM-antibodies secreting hybridoma cultures, of which about 30% showed cross reaction with human and bull spermatozoa. Four stable cell lines were selected for this study secreting antibodies directed against the outer acrosomal membrane of boar spermatozoa. Whereas the polyclonal immune mouse serum stained the entire acrosomal cap, the four hybridoma antibodies generated a patch-work-like immunofluorescence pattern over the acrosome. HPLC-ELISA of the solubilized OAM revealed first information on the nature of the corresponding membrane antigen.  相似文献   
7.
BACKGROUND: Since the advent of cisplatin-based chemotherapy, the majority of metastatic testicular cancers can be cured by chemotherapy followed by retroperitoneal lymph node dissection (RPLND). However, postchemotherapy RPLND confers no therapeutic benefit if the residual mass contains no viable cells. Therefore, to determine which parameters predict a patient's likelihood of having only necrosis in the residual mass, we retrospectively analyzed clinical parameters of patients who underwent postchemotherapy RPLND. METHODS: Data from 27 patients with metastatic testicular cancer were analyzed. The histology of the primary tumor was seminoma in 11 cases and non-seminoma in 16 cases. All of the patients with non-seminoma showed a normalization of tumor markers after chemotherapy. Analysis of clinical parameters included data for the initial histology, pretreatment tumor marker levels, postchemotherapy retroperitoneal mass size, and the histology of the dissected RPLNs. RESULTS: Histological examination of dissected RPLNs showed residual tumor in 27% of seminoma patients and 38% of non-seminoma patients. In seminoma patients, no viable cells were found in all six patients with pretreatment lactate dehydrogenase (LDH) levels below 7.5 times the upper limit of normal, or in all five of the patients with postchemotherapy RPLNs less than 2.5 cm. In non-seminoma patients, no viable cells were found in nine of 10 patients with pretreatment alpha-fetoprotein (AFP) levels less than 2700 ng/mL, or in eight of nine patients with residual mass less than 2.5 cm. CONCLUSIONS: Both postchemotherapy RPLN mass size and pretreatment tumor marker levels are possible predictors for necrosis of the residual mass in testicular cancer patients.  相似文献   
8.
A 33-year-old man with a left testicular tumor was referred to Shinshu University Hospital for advanced therapy. Radiographic imaging revealed multiple metastases in the retroperitoneal lymph nodes (RPLN) and bilateral lungs, as well as tumor thrombus that extended from the left renal vein to the inferior vena cava (IVC) adjacent to the right atrium. After orchidectomy, a diagnosis of embryonal carcinoma was made with a clinical stage of T1N2M1bS3, which has a poor prognosis, based on the International Germ Cell Cancer Collaborative Group consensus. After eight courses of chemotherapy, the patient's tumor markers normalized and the lung metastases disappeared, but the RPLN and tumor thrombus remained. Retroperitoneal lymph node dissection and thrombectomy were performed using a veno-venous bypass (VVB). The pathological examination of the thrombus revealed a mature teratoma. The patient has been disease-free since surgery.  相似文献   
9.
Proportionate cancer mortality was analyzed among white male carpet and textile workers in five northwest Georgia counties for the years 1970-1984. Compared with other Georgians, carpet and textile workers had higher proportions of lymphocytic leukemia (proportionate cancer mortality ratio [PCMR] = 2.9; 95% CI = 1.4-5.4]) and testicular cancer (PCMR = 3.2; 95% CI = 1.0-7.5). The excess mortality from lymphocytic leukemia was even higher when the analysis was limited to workers deemed most likely to work directly in production areas (PCMR = 4.2; 95% CI = 1.7-8.7). Further studies are needed to determine if the observed excesses are the result of workplace exposures.  相似文献   
10.
Treatment of non-seminomatous testicular cancer often leadsto infertility due to anejaculation/retrograde ejaculation andpoor sperm quality. In these men spermatozoa may be obtainedby transrectal electroejaculation (TE), but the optimal strategyfor assisted procreation in these couples is not known. Ouraim was to examine whether TE and conventional in-vitro fertilization(IVF) would be successful. A total of 10 couples, with long-standinginfertility due to anejaculation or retrograde ejaculation aftertreatment for testicular cancer 5–14 years earlier, werereferred to our unit. All men underwent diagnostic TE undergeneral anaesthesia. Spermatozoa were recovered in nine cases.The antegrade fraction was prepared and used for IVF. Spermquality was variable and conventional IVF was considered impossiblein three cases. Altogether six IVF treatment cycles in six couplesresulted in five pregnancies, of which four resulted in a deliveryand one resulted in a spontaneous abortion. One additional pregnancyis ongoing after transfer of cryopreserved embryos. The fertilizationrate was 54% (33/61) and the cleavage rate was 97% (32/33).No complications relating to the procedure have been encountered.  相似文献   
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