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91.
A non‐synonymous, single nucleotide polymorphism (SNP) in the gene coding for steroid 5‐α‐reductase type 2 (SRD5A2) is associated with reduced conversion of testosterone to dihydrotestosterone (DHT). Because SRD5A2 participates in the regulation of testosterone and cortisol metabolism, hormones shown to be dysregulated in patients with PTSD, we examined whether the V89L variant (rs523349) influences risk for post‐traumatic stress disorder (PTSD). Study participants (N = 1,443) were traumatized African‐American patients of low socioeconomic status with high rates of lifetime trauma exposure recruited from the primary care clinics of a large, urban hospital. PTSD symptoms were measured with the post‐traumatic stress symptom scale (PSS). Subjects were genotyped for the V89L variant (rs523349) of SRD5A2. We initially found a significant sex‐dependent effect of genotype in male but not female subjects on symptoms. Associations with PTSD symptoms were confirmed using a separate internal replication sample with identical methods of data analysis, followed by pooled analysis of the combined samples (N = 1,443, sex × genotype interaction P < 0.002; males: n = 536, P < 0.001). These data support the hypothesis that functional variation within SRD5A2 influences, in a sex‐specific way, the severity of post‐traumatic stress symptoms and risk for diagnosis of PTSD. © 2013 Wiley Periodicals, Inc.  相似文献   
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Congenital adrenal hyperplasia (CAH) is a group of disorders affecting the adrenal steroid synthesis. The most common form, 21-hydroxylase deficiency (21-OHD), leads to decreased production of cortisol and aldosterone with increased androgen secretion. In classic CAH, glucocorticoid treatment can be life-saving and serves to bring the symptoms under control. However, the treatment challenge is to effectively control the excess androgen effect by using the lowest possible glucocorticoid dose. Previous studies suggested a relationship between ovarian cyst formation and adrenal androgen excess, but neonatal large ovarian cysts have been very rarely reported in newborns with CAH. Here, we present the unique case of a neonate with classical 21-OHD who underwent surgery for a giant (10x8x7 cm) unilateral solitary ovarian follicular cyst on the 2nd postnatal day. Hormonal evaluation of the patient revealed high-dose hook effect for serum testosterone levels for the first time by a two-site immunoradiometric assay. Possible mechanisms by which androgen excess may cause ovarian cyst formation are discussed.  相似文献   
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Androgen deprivation therapy (ADT) is a standard treatment for metastatic, recurrent and locally advanced prostate cancer (PCa). The aim of this study is to investigate the timing and extent of testosterone recovery in clinically localized PCa patients treated with radical prostatectomy (RP) and subsequent short-term adjuvant ADT. A total of 95 localized PCa patients underwent RP and 9-month adjuvant ADT were included in this prospective study. Serum testosterone level was measured before adjuvant ADT, at ADT cessation, and at 1, 3, 6, 9 and 12 months after cessation of ADT. A Cox proportional hazards model was used to assess variables associated with the time of testosterone normalization. The results showed that median patient age was 67 years and median testosterone level before adjuvant ADT was 361 (230–905) ng dl−1. All patients finished 9-month adjuvant ADT and achieved castrate testosterone level. At 3 months after ADT cessation, testosterone recovered to supracastrate level in 97.9% patients and to normal level in 36.9% patients. The percentage of patients who recovered to normal testosterone level increased to 66.3%, 86.3% and 92.6% at 6, 9 and 12 months, respectively. Cox regression model found that higher baseline testosterone level (≥300 ng dl−1) was the only variable associated with a shorter time to testosterone normalization (hazard ratio: 1.98; P = 0.012). In conclusion, in most patients, testosterone recovered to supracastrate level at 3 months and to normal level at 12 months after 9-month adjuvant ADT cessation. Patients with higher baseline testosterone level need shorter time of testosterone normalization.  相似文献   
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目的观察西地那非联合十一酸睾酮治疗糖尿病患者阴茎勃起障碍的疗效和安全性.方法2009年1月至2011年12月多中心收集广州市番禺区中心医院、上海交通大学医学院附属仁济医院、上海市中医医院泌尿男科门诊糖尿病性勃起功能障碍患者共100例,患者签署知情同意书后,根据国际勃起功能指数表(IIEF-5)进行自我评分.随机分为两组:A组:50例,控制血糖常规治疗的基础上服用西地那非(50mg prn)加十一酸睾酮(80mg/Bid);B组:50例,在控制血糖常规治疗的同时给予西地那非治疗,两组均治疗12周.观察两组患者治疗前后的疗效,并记录患者服药后的不良事件以评价其安全性.结果共计82例完成本次研究,其中A组42例、B组40例.两组患者IIEF-5评分在治疗后均显著增加,而A组较B组增加更显著,差异具统计学意义(P<0.05).治疗后每周性交频率均显著增加,A组较B组增加更明显,差异具统计学意义(P<0.05).其中A组显效率高达59.5%,有效率为88.1%,明显高于B组(显效率30.00%,有效率55.00%),P<0.05.A组37例患者性交时阴茎能满意勃起,而B组只有22例患者性交时阴茎能满意勃起;两组均未出现任何不良反应.结论西地那非联合十一酸睾酮治疗糖尿病性勃起功能障碍较单用西地那非可显著改善患者的勃起能力,且安全性好.  相似文献   
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Effect of normobaric hypoxia on the testis in a murine model   总被引:1,自引:0,他引:1  
High‐altitude hypoxia generates spermiogram impairment due to germinal epithelium, Leydig cells, sperm and seminal plasma alterations, but precise mechanisms involved are unknown. The objective of this work was to analyse the effect of normobaric hypoxia on the morphology of testicular interstitium and some associated molecular and hormonal factors. Twenty‐four mice were exposed to normobaric hypoxia (8.1% inspired oxygen fraction) during 20 days. The effects on body weight, testicular weight, vascularisation, testosterone, HIF1‐α and VEGF were analysed at different periods of exposure and compared to controls. Hypoxic mice had lower body weight than mice kept in normoxia. Testicular weight raised significantly the 1st day, but remained normal during the rest of experiment. Number of blood vessels per field and mean diameter of vessels were higher in hypoxic mice. Plasmatic and testicular testosterone raised during first 24 h of hypoxia, but decreased on the 5th day. Vascular/interstitial ratio (proportion of interstice occupied by blood vessels) duplicated at the end of the experiment. Most substantial early effects of hypoxia were testicular oedema, increase in number and diameter of blood vessels and elevation of plasmatic and testicular testosterone. Normobaric hypoxia generates similar effects to those induced by hypobaric hypoxia.  相似文献   
99.
This study aimed to assess the cavernous antioxidant effect of green tea (GT), epigallocatechin‐3‐gallate (EGCG) with/without sildenafil citrate intake in aged diabetic rats. One hundred and four aged male white albino rat were divided into controls that received ordinary chow, streptozotocin (STZ)‐induced aged diabetic rats, STZ‐induced diabetic rats on infused green tea, induced diabetic rats on epigallocatechin‐3‐gallate and STZ‐induced diabetic rats on sildenafil citrate added to EGCG. After 8 weeks, dissected cavernous tissues were assessed for gene expression of eNOS, cavernous malondialdehyde (MDA), glutathione peroxidase (GPx), cyclic guanosine monophosphate (cGMP), and serum testosterone (T). STZ‐induced diabetic rats on GT demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats. Diabetic rats on EGCG demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats or diabetic rats on GT. Diabetic rats on EGCG added to sildenafil showed significant increase in cavernous eNOS, cGMP and significant decrease in cavernous MDA compared with other groups. Serum T demonstrated nonsignificant difference between the investigated groups. It is concluded that GT and EGCG have significant cavernous antioxidant effects that are increased if sildenafil is added.  相似文献   
100.
Many medicinal plants are designed to improve health but their mechanism of action remains not clear. Among these plants, garlic (Allium sativum) has attracted particular attention of modern medicine because of its widespread use for the prevention and treatment of some human diseases such as cardiovascular diseases and cancer. However, the impact of garlic on the male reproductive system has not been clearly defined. Some studies have reported that garlic improves male sexual function and has beneficial effect in the recovery of testicular functions. However, other authors have shown that this plant impairs testicular functions (such as inhibition of testosterone production) and has spermicidal effect on spermatozoa. In this review, we attempt to clarify the current ambiguity regarding the effects of garlic and its preparations on the male reproductive system.  相似文献   
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