硒对鸡胚脑发育的影响

目的观察补硒对正常鸡胚脑谷胱甘肽过氧化物酶(GPx)、Ⅱ型脱碘酶(IDⅡ)活性和生长相关蛋白(GAP-43)表达的影响,探讨硒对正常动物脑发育的作用。方法对孵育8 d的鸡胚分别注射不同剂量的MSeC(含0、1、5、10、20、40 μg硒),孵育至第20天时处死。测定脑组织中硒、GPx活性、IDⅡ活性,检测GAP-43蛋白的表达。结果对正常鸡胚补硒,可提高脑硒水平、脑GPx活性及GAP-43的表达,补硒量与脑硒、脑GPx活性显著相关(P< 0.01),而与脑IDⅡ活性无相关性。结论MSeC可有效提高鸡胚脑组织硒水平、脑GPx活性和GAP-43的表达,对脑IDⅡ活性没有影响。对正常鸡胚适量补硒可能会促进神经系统的生长和发育。     

Genotype-by-smoking interaction for leptin levels in the Metabolic Risk Complications of Obesity Genes project

RATIONALE: Recently, we identified a genotype-by-smoking status interaction with serum leptin levels in a sample of Mexican Americans. However, it is unknown whether this phenomenon occurs in other populations as well. OBJECTIVE: The goal of this study was to examine the genetic architecture of the response to smoking in leptin levels using data from Midwestern Caucasian subjects participating in the Metabolic Risk Complications of Obesity Genes project. METHODS: We employed a variance decomposition analysis using maximum likelihood methods to model genotype-by-smoking interactions for leptin levels and examined the impact of the exclusion of smokers in a subsequent linkage analysis. RESULTS: We found significant evidence (p-value=0.027) for a genotype-by-smoking status interaction for serum leptin levels. In the subsequent linkage analysis with smokers excluded, we obtained a maximum LOD score of 3.4 (P=0.00004) near D8S1128. CONCLUSIONS: These results suggest that a QTL on chromosome 8 may have a differential effect on the expression of leptin in smokers vs nonsmokers, as first identified in Mexican Americans.     

高血压患者空腹血游离脂肪酸组成与腰臀比、胰岛素活性的关系

目的观察原发性高血压患者空腹血游离脂肪酸(freefattyacid,FFA)组成与向心性肥胖、胰岛素抗性、年龄、血清锌和饮食的关系及性别差异。方法采用社区人群整群抽样、病例对照方法,筛选出高血压患者109例,其中肥胖患者70例,非肥胖患者39例,并以饮食习惯相近的123例血压正常个体(其中肥胖个体66例,非肥胖者57人)为对照,用高效液相色谱直接衍生化法检测空腹血清各种FFA浓度,放免法测定胰岛素水平。结果(1)多元逐步线性回归和分层分析显示空腹血清FFA组成(包括n3PUFA水平、P/S比值、C20:5/C18:3、C22:6/C20:5及C20:4/C18:2比值)存在年龄和性别差异,即小于45岁年龄组高血压患者的FFA改变显著性大与超过46岁年龄组,男性高血压患者的FFA改变显著性大于女性。(2)分层、相关及回归分析显示空腹血清FFA组成与腰臀围比值、胰岛素敏感指数、血清锌水平、饮食习惯相关(均P<0.05)。(3)原发性高血压患者血清锌水平略低于非高血压个体(14.9±5.0vs非高血压组16.8±6.4)μmol/L,P=0.45。结论原发性高血压患者空腹血游离脂肪酸组成改变与向心性肥胖、胰岛素抵抗、锌缺乏、年龄和饮食有关,并存在性别差异。     

新发高血压病人游离脂肪酸与动脉弹性变化

目的观察一个人群中新发高血压病人和未发生高血压者基线空腹血清游离脂肪酸(FFA)与2年内动脉弹性的变化的相关性,探索血清FFA、动脉弹性及高血压之间的关系。方法一纵向研究。社区筛选128例健康非高血压者(年龄33～60岁),随访2年。记录新发高血压例数,采用CVProfilorDO-2020型动脉弹性功能测定仪检测两组2年前后大、小动脉弹性指数(C1和C2),测定基线空腹血FFA、血脂、血糖、胰岛素等。随访期间,有12人失访。结果1)与未发生高血压者(n=97)相比,新发高血压病人(n=19)基线空腹血清饱和脂肪酸水平增高[(217±68)μmol/L比未发生高血压组:(186±46)μmol/L,P=0.04],而多不饱和与饱和脂肪酸比值(P/S)降低(1.60±0.37比未发生高血压组:1.90±0.46,P=0.009);2)与未发生高血压者相比,新发高血压者2年的收缩压和舒张压水平增高(P均<0.01),而其大、小动脉弹性指数改变值(ΔC1和ΔC2)有降低趋势(P均>0.05);3)逐步线性回归模型分析显示:全部参与者2年的ΔC1与基线空腹血清P/S正相关(标准回归系数0.201,P=0.041),独立于基线收缩压水平和经典的心血管危险因素。4)Logistic回归模型分析显示新发高血压者的基线空腹血清P/S的优势比(OR值)和95%可信区间为0.412(0.172～0.991,P=0.048)(在调整了经典的高血压危险因素后)。结论空腹血FFA组成异常是中青年非高血压人群大动脉弹性年龄相关改变和发生高血压的危险因素之一。     

Effects of subdermal implants of estradiol and testosterone on the endometrium of postmenopausal women.

A retrospective review of the medical records of 258 postmenopausal patients using estradiol and testosterone implants as combined hormone therapy was carried out to evaluate the effects of testosterone on the endometrium after two years of continuous use. Endometrial thickness was measured by ultrasonography. Histology was performed on samples of thickened endometria obtained during hysteroscopy with biopsy. In the 44 patients in whom endometrial thickening was >5 mm at the end of the second year of implant use, the most frequent finding at hysteroscopy was polypoid lesion in 61.3% of cases, followed by normal uterine cavity in 31.8% of cases and submucous myoma in 6.8%. Histology of the endometrial samples confirmed endometrial polyp in 38.6% of cases, a histologically normal endometrium in 31.8% of cases, simple endometrial hyperplasia in 20.4% of cases, and myoma and atrophic endometrium in 4.5%. It is possible that testosterone may exert its antiproliferative effects on the endometrium but not on polyps in an action similar to that exerted by combined estrogen/progestin therapies. A greater incidence of simple, low-grade endometrial hyperplasia was found in our study compared with studies using continuous estrogen/progestin regimens. The use of progestins as the ideal endometrial protection should therefore be reconsidered.