男性电磁辐射职业暴露与其子代性别比关系的Meta分析

目的:探讨男性电磁辐射职业暴露与其子代性别比之间的关系。方法:检索国内外各类大型数据库发表的有关男性电磁辐射职业暴露与其子代性别比关系的文献,采用Meta分析的方法,通过Stata 11.0软件评价二者之间的关系。结果:Meta分析结果表明暴露于职业环境电磁辐射的男性其子代性别比与非暴露于电磁辐射者子代性别比没有统计学差异,OR值为1.00(95%CI:0.95～1.05),P=0.875。按照研究类型分层分析,病例对照组和队列组是否暴露于职业环境电磁辐射的男性的子代性别比均无统计学差异,OR值分别为:1.03(95%CI:0.99～1.08),P=0.104;0.98(95%CI:0.99～1.08),P=0.186。结论:男性有无电磁辐射的职业暴露与其子代性别比之间未发现明显相关。     

Sperm speed is associated with sex bias of siblings in a human population

Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis. Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human populations. It has been hypothesized that offspring sex may be adaptively manipulated to maximize the offspring''s reproductive fitness (e.g., parents with genes for good male fertility traits, such as high sperm speed, would produce primarily sons and fewer daughters because the offspring will inherit advantageous male fertility genes). Conversely, parents with poor male fertility genes would produce primarily daughters. We tested whether there was an association between how fast a man''s sperm swam and the sex bias of his siblings in a sample of men attending clinic for fertility investigations with their partner and with a wide range of semen characteristics, including sperm speed. We found that the sex bias of a man''s siblings is associated with his sperm speed; men with female-biased siblings had significantly slower sperm (judged using computer-assisted sperm analysis (CASA)) than men from male-biased sibships. This observation suggests family composition is an important factor that needs to be considered in future epidemiological and clinical studies of human fertility.     

宫内七氟醚暴露对仔鼠海马CA1区caspase-3表达及早期认知功能的影响

目的研究宫内暴露于七氟醚对仔鼠海马CA1区神经元凋亡及早期认知功能的影响。方法成年性成熟Wistar雌鼠交配妊娠后取孕鼠8只,随机分为对照组七氟醚组,每组4只。七氟醚组于孕19天时暴露于2.4%七氟醚6h,对照组不给予任何药物。应用免疫组化法观察两组仔鼠在出生后第1天(PN1)、第14天(PN14)、第21天(PN21)海马CA1区caspase-3的表达情况。出生后32~37天对仔鼠进行Morris水迷宫实验以测定其认知功能。结果出生后第1天,七氟醚组仔鼠海马CA1区caspase-3总光密度值(IOD)明显高于对照组仔鼠[(60309.6±6403.6)比(17680.5±9326.7),P0.05],出生后第14、21天,七氟醚组仔鼠海马CA1区caspase-3总光密度值与对照组仔鼠相比,差异无统计学意义[(3213.7±582.8)象素比(8503.2±2402.5)象素,(2046.0±62.7)象素比(4839.9±716.3)象素,P0.05]。七氟醚组仔鼠逃避潜伏期与对照组仔鼠相比,差异无统计学意义[(80.0±13.5)s比(80.7±19.1)s,(52.2±10.3)s比(41.0±19.7)s,(29.2±11.4)s比(28.5±15.3)s,(22.0±5.5)s比(19.2±6.7)s,(16.2±2.8)s比(20.3±4.8)s,P0.05],七氟醚组仔鼠穿越目标象限次数与对照组仔鼠相比无统计学差异[(8.3±0.8)次比(8.2±3.0)次,P0.05]。结论孕晚期Wistar母鼠暴露于2.4%七氟醚对仔鼠海马CA1区神经元发育的影响呈"一过性损伤",并不会引起子代早期认知功能异常。     

孕晚期母亲睡眠与子代2岁胰岛素和胰岛素抵抗的相关性研究

目的 通过建立出生队列研究孕晚期母亲睡眠与子代2岁胰岛素水平和胰岛素抵抗之间的相关性。方法 在上海浦东新区仁济医院招募255位健康孕晚期(孕36~38周)母亲及其婴儿入组,采用手表式睡眠-活动记录仪(actigraph)评估孕晚期母亲的睡眠状况,在儿童2岁时采集随机静脉血,检测血糖和胰岛素水平。胰岛素抵抗用HOMA-IR来评估,HOMA-IR=[血糖(mmol/l)×胰岛素(μU/ml)]/22.5。结果 儿童在2岁时平均血糖为(4.58±0.53)mmol/L,胰岛素为(4.65±3.61)μU/mL,HOMA-IR为0.98±0.84。在校正了孕晚期母亲年龄,受教育程度,家庭经济收入和儿童性别之后,孕晚期母亲夜间入睡后觉醒时间越长,其子代在2岁时的胰岛素水平越高(β=0.236,P=0.016),胰岛素抵抗指数越高(β=0.241,P=0.015)。结论 孕晚期母亲入睡后觉醒时间与其子代2岁时胰岛素和胰岛素抵抗密切相关,提示孕期保健医护人员应密切关注并改善孕晚期母亲的睡眠状况,以改善子代的代谢结局。     

胆红素脑病仔鼠脑组织S-100的mRNA及其蛋白变化研究

目的：观察胆红素脑病仔鼠脑组织S-100蛋白（S-100）的mRNA及其蛋白变化．探讨其对胆红素脑病的诊断价值和其分子生物学机制。方法：采用新生7d龄清洁级Wistar大鼠腹腔注射胆红索200mg／kg制备胆红素脑病模型。应用逆转录-聚合酶链反应（RT—PCR）技术动态观察胆红素脑病仔鼠不同时间点脑组织S-100 mRNA表达变化；应用免疫组织化学方法动态观察不同时间点脑组织S-100蛋白表达变化。结果：实验组脑组织S-100 mRNA表达12h明显升高．48h达峰值．至96h与对照组差异无显著性意义：造模后12h海马区脑组织S-100阳性表达明碌升高，48h达峰值，至96h与对照组无显著性差异；皮质区6h明显升高。48h达峰值，至96h与对照组差异无显著性意义；丘脑区6h明显升高，72h下降，至96h与对照组无显著性差异；苍白球区6h明显升高，48h达峰值，72h下降，至96h与对照组比较仍有显著性差异。结论：S-100mRNA的变化同S-100蛋白的变化趋势一致，是判定胆红素脑病的可靠神经生化指标。     

孕期丰富环境对子代小鼠学习记忆功能的影响

目的探讨雌性小鼠孕期给予丰富环境刺激对子代新生小鼠空间学习记忆能力的影响。方法选择SPF级C57BL／6受孕雌鼠24只随机分为丰富环境组和标准环境组,在整个孕期分别给予丰富环境、普通环境的刺激直至分娩为止。两组小鼠出生后均移至普通环境饲养,在出生后的1个月及2个月时分别对子代小鼠进行水迷宫行为学检测、海马区新生神经元的免疫荧光检测。结果在1月龄的子代小鼠中,定位航行实验显示丰富环境组比普通环境组小鼠的平均逃避潜伏期时间明显缩短（P〈0．05）,而空间探索实验显示丰富环境组平台象限游泳距离百分比和穿台次数均高于普通环境组（P〈0．05）。在海马CA1区和齿状回,丰富环境组神经元前体细胞标记物微管相关蛋白Doublecortin（DCX）阳性神经细胞数目较普通环境组明显增多（P〈0．05）。而在2月龄的子代小鼠检测中,两组小鼠在上述指标均无明显统计学差异。结论在母鼠妊娠期间给予丰富环境刺激可以一过性提高子代小鼠的学习记忆能力以及神经发生发育。     

母鼠低剂量接触甲基汞所致仔鼠学习能力及脑海马超微结构的变化

[目的]研究ICR母鼠饮水暴露低剂量氯化甲基汞(MeHgCl)后,仔鼠脑组织的病理组织学变化和脑海马超微结构变化,评价低剂量饮水暴露甲基汞的安全性。[方法]ICR孕鼠随机分为对照组、低剂量组和高剂量组,每组各8只,各组于怀孕第6天起,分别自由饮用蒸馏水和氯化甲基汞含量为0.01、0.1mg/L的蒸馏水,直至哺乳期结束。测试各组仔鼠学习能力,观察仔鼠脑组织病理组织学变化及脑海马超微结构变化。[结果]在对仔鼠进行学习能力测试的水迷宫实验中,对照组、低剂量组和高剂量组成功率分别为81.67%、59.09%和70.00%,低剂量组和高剂量组成功率显著低于对照组(P<0.05)。低剂量组和高剂量组仔鼠脑组织有明显的病理学改变,随着甲基汞染毒剂量的增加,海马区大锥体细胞、大脑神经元和小脑浦肯野细胞嗜酸性增强。电镜结果显示,低剂量和高剂量组脑海马神经细胞有变性,严重者呈暗细胞表现。[结论]实验剂量甲基汞可使仔鼠脑组织发生病理组织学改变,脑海马区超微结构改变,实验剂量甲基汞对于仔代是不安全的。     

Cyclophosphamide in the male rat: behavioral effects in the adult offspring

Cyclophosphamide in a daily dose of 10 mg/kg was injected intraperitoneally in male Wistar rats for 15 days. Two rats each time were killed for testis examination at regular intervals within 100 days following treatment (over 2 spermatogenetic cycles). One hundred days after the end of the treatment, the other rats, whose spermatogenesis had recovered in the meantime, were mated with 3-month-old females. Offspring were evaluated in regard to the mean number per litter, sex ratio, frequency of gross external malformations, growth pattern, mortality in the first 4 months of life and reproductive ability at 6 months of age. Offspring behavior was also examined between 10 and 14 weeks of age. They were evaluated for spontaneous activity and emotionality with an open field test and for learning ability with an avoidance conditioning test. Cyclophosphamide induced a significant decrease in the number of primary spermatocytes and spermatozoa. Only learning ability was altered in the offspring from the treated males, for the animals which succeeded in the avoidance conditioning test did not learn as rapidly as the controls. However, the difference was significant only in the males. Behavioral abnormalities and the possible genetic factors involved are related to the particular concept of 'physioteratogenesis'.