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61.
Carbamazepine (CBZ) is used in the control of seizure and affective disorders, causing hypothyroidism. Thyroid hormones regulate the Sertoli cell proliferation and differentiation. Clinical aspects must be considered since epileptic fertile women need to continuously use CBZ during pregnancy and lactation. This study aimed to evaluate the effects of CBZ on testis development of rat offspring from dams treated during pregnancy/lactation. Rat dams received CBZ (20 mg kg−1 day−1) or vehicle by intra-peritoneal route during gestation and lactation. Progenies were euthanised at 4, 14, 41, 63 and 93-days post-partum (dpp) for the evaluation of T3, T4 and TSH plasma total levels. Testicular cross sections were submitted to anti-Ki67, anti-PCNA, anti-p27kip1 and anti-transferrin immunolabelling for the evaluation of Sertoli cells. There was a significant reduction in p27kip1-positive Sertoli cell numerical densities and an increase in TSH level at 14 dpp. CBZ exposure affected the volume density of transferrin-positive immunolabelling at 63 dpp. These results suggest that CBZ may cause a dysregulation of the controller system of thyroid hormones homeostasis leading to an increase in the proliferation rate at the neonatal phase and a differentiation delay of the Sertoli cell, culminating in an altered function at late puberty. The occurrence of hypothyroidism cannot be completely discarded.  相似文献   
62.
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm.  相似文献   
63.
The blood–testis barrier (BTB) of Sertoli cells (SCs) is an important biological barrier that maintains spermatogenesis and provides a favourable microenvironment for spermatogenesis. However, heat stress can directly damage the BTB structural proteins of testicular SCs, leading to dyszoospermia. Wuzi Yanzong Pills (WYP) is a traditional Chinese medicine formula used to treat male reproductive diseases. However, whether WYP could ameliorate heat stress injury in primary SCs extracted from rat testes and BTB proteins remains unknown. Here, treatment with WYP (low, medium and high dose) increased the SC viability and the proliferation of cell antigen Ki67 significantly. Additionally, it promoted SC maturation, which presented in the form of increased androgen receptors (ARs) and decreased cytokeratin 18 (CK-18) in three WYP dose groups. WYP upregulated BTB proteins such as zonula occludens 1 (ZO-1) and occludin across all WYP groups and decreased phosphorylated Akt (p-Akt) in the middle and high-dose groups; however, ZO-1 and occludin recovery were reduced with the presence of Akt inhibitor in WYP groups. WYP improved SC viability and proliferation, and ameliorated dedifferentiation and BTB-proteins damaged by heat stress via Akt signalling. The findings present theoretical support for the effects of WYP in the management of dyszoospermia and male infertility.  相似文献   
64.
Klinefelter syndrome (KS) is a common disorder and almost every clinician in almost every sub-specialty of medicine will knowingly or unwittingly treat boys or men with a 47,XXY chromosomal constitution. Although there are numerous aspects of KS worthy of discussion, this contribution will focus specifically on the controversial, and as yet unresolved, issue of whether it is advantageous to harvest testis tissue from peri-pubertal or adolescent boys with KS in a heroic effort to preserve that child’s chances of reproduction in his future adult life. What would be the rationale for that, how does the biology of spermatogenesis in the Klinefelter testis impact that decision, and what does the data show? The answer, assembled from a selection of seemingly disparate sources and directions, appears to be “No”. We do not have to advocate for an aggressive approach, we do not have to preemptively preserve future fertility. We can justifiably wait until adulthood with equivalent chances of success.  相似文献   
65.
目的 研究P物质 (SP)对睾丸细胞分泌睾酮 (T)的影响。方法 应用细胞培养技术和放谢免疫测定法研究不同浓度的P物质对睾丸细胞分泌睾酮是否有直接作用。结果 实验组 (加入SP)的培养液T的含量比对照组 (未加SP)明显减少。实验组分别与对照组进行两两比较 (t -test)并采用单因素方差分析 ,P均 <0 0 1差异有高度的显著性。结论 P物质对培养的大鼠睾丸细胞分泌T有直接抑制作用 ,且随着浓度增加 ,抑制作用增强  相似文献   
66.
阑尾类癌11例临床分析   总被引:1,自引:0,他引:1  
目的:总结阑尾类癌的诊断及治疗经验,提高首次手术治愈率。方法:回顾性分析11例阑尾类癌,分别采和单纯性阑尾切除术6例,回盲部切除术1例,右半结肠切除3例,姑息性手术1例。结果:全组无1例术前诊断,均经术后病理确诊。10例治愈,1例死亡。结论:该病少见,难以做出术前确诊。宜根据肿瘤大小、部位及浸润深度决定手术方式和切除范围。  相似文献   
67.
用免疫组织化学方法观察基因基白c-erbB2在大鼠睾丸中的分布。结果:未成年大鼠睾丸生精上皮细胞和间质细胞中均未见c-erbB2免疫染色阳性颗粒,成年大鼠睾丸曲细精管中的圆形精子细胞,精子和残体均可见c-erbB2蛋白存在。提示原癌基因c-erbB2的活性可能参与精子形成的调控。  相似文献   
68.
Inflammatory pseudotumors have been recognized in many parts of the body. A case of a diffuse variant which involved the testis, the epididymis and the spermatic cord is described. The patient had enlarged left testis for several months. Clinically, the lesion mimicred cancer. Histologically, the lesion contained hyalinized fibrous tissue with spindle cells, plasma cells and lymphocytes. Gradual involvement of vascular channels by the cellular elements of inflammatory pseudotumor was observed. Results of immunohistochemical studies showed a myofibroblast differentiation in the majority of spindle cells: intense antibody staining for smooth muscle actin, muscle specific actin, and vimentin. The ultrastructural findings, intracytoplasmic filaments with dense bodies, were also consistent with the myofibroblastic nature of these cells. The histiocyte differentiation of spindle cells is questionable in our case, because only scattered histiocyte-like cells showed positivity with the KP-1 (CD-3) antibody.  相似文献   
69.
Tubular ectasia of the rete testis: a potential pitfall in scrotal imaging   总被引:1,自引:0,他引:1  
Tubular ectasia of the rete testis (TERT) is a benign entity due to dilation of the tubules of the rete testis. Most of the time it is discovered incidentally on scrotal sonograms and may be misinterpreted as malignant. This article outlines the diagnostic criteria of TERT, its possible causes, its incidence and its potential evolution. Recognizing this entity owing to its characteristic clinical, sonographic and, if necessary, MRI features is important to avoid unnecessary surgery or biopsies. Received: 4 August 1998; Revised: 15 April 1999; Accepted: 19 April 1999  相似文献   
70.
Aim: To find out the toxic effect of endosulfan on the tesficular function of pubertal rats, Methods: Male rats of pu-bertal age were orally administered endosulfan at a dose of 1.0 mg/kg body weight for 30 days. Twenty-four hours af-ter the last tmagnent, the rats were sacrificed and the testis, epididymis, seminal vesicles and ventral prostate were re-moved and weighed. A 10 % testicular homogenate was prepared for biochemical estimations. Results: In endosul-fan-treated rats, there were a reduction in the body weight and the weights of testis and accessory sex organs, a de-crease in the testicular lactate and pyruvate activities, and in the testicular DNA and RNA concentrations, whereas thetesticular protein concentration was slightly increased; the specific activity of testicular steroidogenic enzyme, 33OH-steroid dehydrogenase and the ascorbic acid level were decreased, which were correlated with a decrease in steroidoge-nesis. The lysosomal enzyme acid phosphatase and brush-border enzyme alkaline phosphatase activities were also de-creased in the testis of treated rats. Conclusion: In puhertal rats, endosulfan treaanent inhibits the testicular functions.(Asian J Androl 1999 Dec; 1 : 203 - 206)  相似文献   
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