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991.
PURPOSE: To determine whether emergency subtraction dynamic contrast-enhanced MR imaging (DCE-MRI) in combination with T2- and T2*-weighted imaging of the testis is useful in the evaluation of patients with testicular torsion. MATERIALS AND METHODS: Fourteen patients with surgically proven testicular torsion were examined using preoperative emergency MRI, including T2-weighted, T2*-weighted, and DCE-MRI. The affected testis was examined histologically in eight patients who underwent orchiectomy, and by postoperative follow-up MRI in six patients who underwent orchiopexy. The diagnostic criteria for testicular torsion and detection of hemorrhagic necrosis in the affected testis in emergency MRI were decreased or no perfusion in DCE-MRI and a spotty and/or streaky pattern of low or very low signal intensity in T2- and T2*-weighted images. The intraoperative findings and clinical outcomes were also compared. RESULTS: The histological findings and follow-up MR images revealed total or partial necrosis of the affected testis in 10 of the 14 patients. In the diagnosis of complete torsion, the sensitivities were 100% for DCE-MRI and 75% for T2- and T2*-weighted imaging. In the detection of testicular necrosis, T2- and T2*-weighted imaging showed the highest accuracy (100%), followed by 12-hour time from onset (93%), intraoperative findings (79%), and DCE-MRI (71%). CONCLUSION: Emergency MRI can help diagnose testicular torsion and detect testicular necrosis when DCE-MRI is used in combination with T2- and T2*-weighted images.  相似文献   
992.
Growth hormone (GH) is known to regulate peripheral components of the hypothalamo-pituitary gonadal (HPG) axis, but it remains unclear whether GH exerts a significant influence on the activity of the hypothalamo-pituitary components of the HPG axis. In this study, we investigated the development of HPG axis function in the male transgenic growth retarded (Tgr) rat, a model of moderate systemic GH deficiency caused by hypothalamic expression of human (h)GH. Impaired postnatal somatotroph expansion and moderate GH deficiency in male Tgr rats were accompanied by a two- to three-fold increase in pituitary gonadotrophin content, but without a significant change in the pituitary gonadotroph population. A three- to nine-fold elevation in basal circulating luteinising hormone concentration was seen in postpubertal Tgr rats, with a smaller increase in follicle-stimulating hormone. Despite this hypergonadotrophism, there was no corresponding increase in steroidogenic (circulating testosterone and seminal vesicle weights) or gametogenic (spermatozoa counts in seminiferous tubules) activity in the postpubertal Tgr testis. Following puberty, the plasma leptin concentration also became progressively elevated in Tgr males. Circulating gonadotrophin and leptin levels were normalised in Tgr rats by peripheral physiological replacement of rat GH, but plasma testosterone concentration was unaffected. These results confirm that hGH exerts a positive influence on the central control of gonadotrophin secretion in the Tgr rat, but the absence of a corresponding elevation in the steroidogenic or gametogenic function of the Tgr testis implies that the peripheral GH/insulin-like growth factor I axis may also exert a permissive influence on testicular function. The relative contribution of somatogenic and lactogenic mechanisms and the potential influence of elevated leptin and decreased sensitivity to androgen feedback to the development of postpubertal hypergonadotrophism in Tgr males remain to be determined.  相似文献   
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The aim of this study is to do a study of cryoinjury and ischaemic injury on testicular graft during cryopreservation and transplantation. According to time at 1, 3, 7 and 14 days after transplantation, the grafts were collected for immunohistochemistry assay for CD34 (blood vessel marker), VEGF (neoangiogenesis marker), caspase-3 (apoptosis marker) MAGE-A4 (germ cell marker). A significant increase was observed in the density of VEGF-positive blood vessels on day 3, reached a peak on day 7. On post-transplant day 3, a sharp increase occurred in the rate of spermatogonia-expressing caspase-3 until the day 7. At 14th day after transplantation, the spermatogonia number per round tubule of nonfrozen grafts was 41 ± 5.9% from that of fresh control tissues, while, in frozen-thawed grafts, the spermatogonia number per round tubule was 36.8 ± 4.6% from that of fresh control tissues. In testicular grafts, angiogenesis initiated reperfusion from day 3, and the formation of new blood vessel generally is completed about 7 days after transplantation. Angiogenesis in grafts after transplantation plays a crucial role in the restoration of function. Therefore, minimising ischaemic injury as well as improvement of cryopreservation protocols are needed to improve testicular graft after freezing, thawing and grafting.  相似文献   
997.
This study was performed to determine the effect of zinc supplementation effects on metallothionein levels in testis ischaemia-reperfusion of rats. The experimental groups were designed as Control, Sham, Ischaemia-Reperfusion (I/R) and I/R + Zinc supplemented. Zinc supplemented as 5 mg/kg day for 3 weeks. Testis tissues were analysed for metallothionein by immunohistochemical staining procedures. Group comparison showed that the zinc-supplemented ischaemia-reperfusion group had a significantly higher level of cells strongly stained with metallothionein than all other groups. A general evaluation of the results suggests that zinc supplementation is a strong stimulant of metallothionein synthesis in the ischaemic testis tissue.  相似文献   
998.
This study aimed to investigate the potentiality of biomodels to be produced as alternative tools to slaughterhouse materials in andrology education. For this purpose, testis biomodels were produced with reference to bull testes. The biomodel production was carried out by the following steps: the preparation of the reference organs, 3D modelling, and processing of data sets and stages. The biomodels and reference testes were compared in terms of morphological parameters and tonicity. As a result of quantitative measurements, the average length in the reference testicles was 145.56 ± 21.3 mm, while the thickness was 61.94 ± 17.2 mm. The average length, thickness, volume and tonicity values of the biomodels showed similarity to the values of the reference testicles (p > .05). However, it was recorded that the average weight of the reference testicles was determined as 368.07 ± 40.3 g, while the average weight of the biomodels was 69.02 ± 3.18 g (p < .01). As a result, it has been shown that testis biomodels can be successfully produced using three-dimensional technologies. These biomodels are the first examples in the field. We think that the biomodels produced by using innovative technologies should be considered as serious alternatives, which could contribute to the learning processes of students, especially in andrology education.  相似文献   
999.
Sexual dysfunction of men is one of the most serious problems in human society. This study aimed to evaluate the protective effect of cinnamon and ginger extract on testicular damages induced by carbon tetrachloride (CCl4). Thirty-six male Wistar rats were randomly divided into 6 groups (n = 6): 1. Normal control; 2. Carbon tetrachloride (CCl4); 3. CCl4 + Cinnamon; 4. CCl4 + Ginger; 5. CCl4 + Cinnamon and Ginger; and 6. Cinnamon + Ginger. CCl4 (1 ml/kg) was injected intraperitoneally on the 14th day, and cinnamon (50 mg/kg, orally) and ginger (250 mg/kg, orally) were administered daily for 14 days. Fifty hours after the CCl4 injection, the testicles and epididymis were separated and examined as to histological alterations and oxidative stress markers. CCl4 significantly increased malondialdehyde level and decreased total antioxidant capacity when compared to the normal control group (p < .05). In addition, degenerative alterations in the testicular and epididymal tissue were observed in CCl4 group. The pre-treatment with ginger and cinnamon extract significantly improved these parameters when compared to the CCl4 group (p < .05). The results of this study indicated that co-treatment of ginger and cinnamon reduces the damages induced by CCl4 in testicular tissue by increasing antioxidant capacity and reducing lipid peroxidation.  相似文献   
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