Hypothalamic-pituitary-testicular function in end-stage non-alcoholic liver disease before and after liver transplantation

OBJECTIVE Gonadal dysfunction is common in chronic liver disease, but most of the previous studies have been restricted to men with alcohol-Induced liver disease. We have evaluated hypothalamic-pituitary-testicular function In patients with end-stage non-alcoholic liver disease before and at 6 and 12 months after hepatic transplantation. DESIGN A prospective study of hypothalamic-pituitary-testicular endocrine function before and after cadaveric hepatic transplantation. PATIENTS Fifty four consecutive patients with end-stage, non-alcohollic liver disease were evaluated before and after liver transplanatation. MEASUREMENTS Hypothalamic-pitultary-testicular(HPT) axis function was evalutated under basal conditions by single morning measurements of plasma total and free testosterone, sex hormone-binding globulin and by plasma LH and FSH responses to 100 μg i.v. GnRH. RESULTS Men with chronic non-alcoholic liver disease had reduced levels of total and free teststerone and increased levels of SHBG compared with controls with normal liver function. Total and free testosterone were positively correlated with basal and stimulated LH (but not FSH) concentrations. Gonadotrophin responses to GnRH were preserved but delayed compared with healthy controls consistent with a predominantly hypothalamic defect in regulation of pitultary-testicular function. Increasing severity of underlying liver disease was associated with declining total and free testosterone as well as peak GnRH-stimulated LH concentrations. Splronolactone treatment was associated with decreased circulating testosterone levels only in men with liver disease of lntermedlate severity (Child-Pugh class B). Following hepatic transplantatlon, total and free testosterone and SHBG concentrations returned progressively towards eugonadal control levels over the first 12 months but total and free testosterone levels remained subnormal. CONCLUSIONS Hypothalamic-pitultary regulation of testicular function Is Impaired in end-stage non-alcoholic liver disease In proportion to the severlty of underlying liver disease. Splronolactone reduces circulating testosterone but only among men with Chlld-Pugh B liver cirrhosis. Gonadal function Improves, but is not normalized, over the first year following successful liver transplantation.     

Nitrate contamination of domestic potable water supplies: a social problem?

Nitrate contamination of potable water supplies is a recognized health hazard. Potentially, the contamination of private drinking water supplies could be a problem in the rural Palouse area of Idaho and Washington. Studies have shown that 12 percent of the rural population of Whitman County, Washington, may be drinking water containing nitrates in excess of the national standard. Yet there is no organized concern about this potential health hazard among local citizens. After reviewing the literature on nitrate contamination of ground water and discussing nitrate contamination of private potable water supplies in the Palouse, we use a social movement theory of social problems to explain why this situation has not been defined as a public health problem.     

抗癌及癌化学预防药物的研究：3α酮醛香豆素衍生物的合成及其抗致突活性与结构间的关系

α酮醛及其衍生物在抗病毒、抗肿瘤方面有一定活性。我们合成了１８个新的３α酮醛香豆素衍生物，研究该类化合物的质谱裂解方式与氢核磁共振谱的特征峰。体外药理筛选发现其中部分化合物有不同程度的抗致突活性，对其构效关系进行了分析，并提出了这类化合物产生抗致突活性的可能亚结构     

诱导性心室纤颤与晶体停搏液灌注具有相同的胎儿心肌保护作用

研究背景　处于宫内发育期间的胎儿如果患有先天性心脏畸形 ,心脏畸形可能逐渐加重 ,因此胎儿心脏外科干预治疗具有潜在的发展空间。怀孕期间实施畸形纠治可能预防由于病理性的血流方式所导致的心腔或大血管发育不良。但是 ,对最佳的胎儿心肌保护研究策略尚未进行深入研究。本研究应用胎儿双心室工作模型 ,对诱导性心室纤颤和晶体停搏液灌注的心肌保护效果进行对比评估。方法　实验用心脏取自孕龄 115～ 12 5天的胎羊。使用Krebs-Henseleit溶液灌注离体心脏。在动脉导管以远结扎降主动脉 ,肺动脉侧枝均结扎以模拟胎儿循环。 1组离体心脏采用常温诱导性心室纤颤 (n =8) ,另外 1组采用低温晶体停搏液灌注使得心脏停搏 (n =8)。之后均恢复Krebs -Henseleit溶液灌注。通过压力直径关系曲线测定心脏停搏前的心功能基础值以及停搏后的心功能指数。结果　停搏后的心脏收缩功能指数检测显示 ,诱导性心室纤颤与晶体停搏液具有相同的心肌保护效果(停搏后左心室收缩指数分别为 70 %± 5 %vs 6 8%± 15 % ,P =0 .5 2 ;右心室收缩指数分别为 6 8%± 4 .5 %vs 6 5 %± 4 .5 % ,P =0 .2 6 )。对于预防舒张期室壁张力的增加 ,两者的作用相似 (左心室分别为 32 %± 5 .3%vs 38%± 11% ,P =0 .2 4 ;右心室分别为 2 5 %± 3     

Flexible bronchoscopy in the evaluation of mediastinal and hilar lymphadenopathy

Background: The diagnosis in cases of mediastinal and/or hilar lymphadenopathy with no lung parenchymal involvement is often difficult. We undertook this study to assess the diagnostic value of flexible bronchoscopy (FOB) especially transbronchial needle aspiration (TBNA) and transbronchial lung biopsy (TBLB) in these patients.     

Clinical presentation of PCOS following development of an insulinoma: case report

A 24 year old woman presented with a prolonged clinical history of fasting and exertional hypoglycaemia, and was subsequently diagnosed with an insulinoma. Concurrent symptoms of oligomenorrhoea and hyperandrogenism of similar duration were noted. Biochemically, hyperinsulinaemia was observed in association with a raised serum luteinizing hormone (LH), raised testosterone and androstendione concentrations. Surgical removal of the insulinoma resulted in resolution of the clinical and biochemical features of the polycystic ovarian syndrome (PCOS) but minimal change was observed in the ovarian ultrasound appearances. This case demonstrates the role of insulin in mediating the hypersecretion of both LH and androgens in women with polycystic ovaries. We suggest that hyperinsulinaemia converted occult 'polycystic ovaries' to become clinically manifest as 'polycystic ovary syndrome'. This paradigm has clear implications for women with insulin dependent diabetes mellitus who presumably have systemic hyperinsulinaemia.     

The Cambrian "explosion": slow-fuse or megatonnage?

Clearly, the fossil record from the Cambrian period is an invaluable tool for deciphering animal evolution. Less clear, however, is how to integrate the paleontological information with molecular phylogeny and developmental biology data. Equally challenging is answering why the Cambrian period provided such a rich interval for the redeployment of genes that led to more complex body plans.     

Bioavailability of iron in two prenatal multivitamin/multimineral supplements

OBJECTIVE: To determine the iron bioavailability in two popular prenatal multivitamin/multimineral supplement tablets containing 27 mg elemental iron. STUDY DESIGN: Iron absorption during an eight-hour period following ingestion of a multivitamin/multimineral formulation, both fasting and with a standardized meal, was measured in a group of 30 pregnant women (24-32 weeks of gestation) and statistically compared. The prenatal formulations were Stuartnatal Plus and Materna (Wyeth-Ayerst Pharmaceuticals, Philadelphia, Pennsylvania), and each contains 27 mg of elemental iron. A placebo was included in the study for the control group in this crossover, single-blind study. RESULTS: The net iron bioavailability (mean +/- SE) of Stuartnatal Plus and Materna, accounting for diurnal variation, and the iron ingested with the standardized meal was 5.4 +/- 0.4 and 4.6 +/- 0.2 mg, respectively, while fasting and 2.9 +/- 0.4 and 2.7 +/- 0.4 mg, respectively, postprandially. The total amount of iron absorption in the fasting states from both prenatal formulations exceeded the 3 mg of supplemental iron absorption per day recommended by the National Academy of Sciences. CONCLUSION: The results of this study indicate that these two prenatal multivitamin/multimineral formulations provide > 3.0 mg of supplemental iron absorption (fasting) as recommended by the National Academy of Sciences and 2.7 mg of iron absorption above the levels achieved following ingestion of a standard, low-iron test meal.