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931.
932.
933.
Although chronic ethanol treatment is known to impair learning and memory, humans commonly consume a range of alcoholic beverages. However, the specific effects of some alcoholic beverages on behavioral performance are largely unknown. The present study compared the effects of a range of alcoholic beverages (plain ethanol solution, red wine, sake and whiskey; with a matched alcohol concentration of 10%) on learning and memory. 6-week-old C57BL6J mice were orally administered alcohol for 7 weeks. The results revealed that red wine treatment exhibited a trend toward improvement of spatial memory and advanced extinction of fear memory. Additionally, red wine treatment significantly increased mRNA levels of brain-derived neurotrophic factor (BDNF) and N-methyl-D-aspartate (NMDA) receptors in mice hippocampus. These results support previous reports that red wine has beneficial effects.  相似文献   
934.
目的:观察低氧性肺动脉高压小鼠肺组织中载脂蛋白E(apoE)蛋白表达的变化,以探讨低氧性肺动脉高压形成过程中apoE蛋白表达的变化及可能的意义。方法:SPF级雄性野生型(WT)C57BL/6小鼠和雄性apoE基因敲除(apoE-KO)小鼠各20只,各随机再分为2组(n=10):常氧组和低氧组,共4组。常压连续低氧3周(9%~11% O2,23 h/d)复制慢性低氧性肺动脉高压模型,采用右心导管法测定小鼠右心室压(RVSP),计算右心室与左心室加室间隔重量比RV/(LV+S),ELISA法检测血浆中高密度脂蛋白(HDL)、低密度脂蛋白(LDL)和总胆固醇(TC)的含量;Western blot法检测肺组织中apoE和过氧化物酶体增殖物激活受体γ(PPARγ)蛋白的表达。结果:①低氧组WT小鼠RVSP、RV/(LV+S)分别较常氧组高68%和59%(P均<0.05),血浆中HDL含量及HDL/LDL比值分别较常氧组低17%和40%(P均<0.05),同时肺、肝组织中apoE及肺组织中PPARγ的蛋白表达分别较常氧组下调48%、52%和37%(P均<0.05),RVSP与apoE及PPARγ蛋白表达均呈显著负相关(P均<0.01);②低氧组apoE-KO小鼠RVSP、RV/(LV+S)较常氧组分别高96%和86%(P均<0.05),低氧组apoE-KO小鼠RVSP和RV/(LV+S)较低氧组WT小鼠分别高29%和24%(P均<0.05)。结论:小鼠低氧性肺动脉高压的形成与肺组织中apoE蛋白表达下调有关。  相似文献   
935.
目的:探讨酒精对丙酸睾酮引起的小鼠前列腺增生(BPH)的作用及其生殖毒性。方法:成年雄性昆明系小鼠70只随机分为空白对照组(Control)、阴性对照组(Negative control,sc大豆油25 mg/(kg·d),ig蒸馏水7.5 ml/(kg·d),连续处理7 d、21 d)、酒精7 d和21 d组(AL7和AL21,ig 50°白酒7.5 ml/(kg·d),连续处理7 d、21 d),丙酸睾酮7 d和21 d组(TP7和TP21,sc丙酸睾酮注射液25 mg/(kg·d),连续处理7 d、21 d),丙酸睾酮+酒精7 d组(TP+AL7,sc丙酸睾酮注射液25 mg/(kg·d),ig50°白酒7.5 ml/(kg·d),连续处理7 d),每组10只。末次处理24 h后处死小鼠,计算小鼠前列腺和睾丸系数,检测精子参数,测定睾丸和前列腺组织中自由基水平、抗氧化能力,观察前列腺组织病理学变化。结果:与对照组、TP7 d组、AL7和AL21 d组相比,TP+AL7 d组的前列腺系数显著提高、精子数量和质量显著降低、前列腺和睾丸MDA含量显著升高、SOD和GPx酶活力显著下降(P均< 0.05);与TP21 d组相比,TP+AL7 d组的前列腺系数无显著差别(P>0.05))。结论:丙酸睾酮和酒精共同处理7 d就可以达到典型的前列腺增生(BPH)状态,并引起睾丸及精子的损伤,导致生殖系统的氧化应激反应增强,说明酒精对丙酸睾酮引起的小鼠前列腺增生有明显的促进作用。  相似文献   
936.
目的了解暴露PM_(2.5)后的Bac荷瘤裸鼠肠道菌群组成的变化。方法采用A549细胞对30只Bac裸鼠进行肺内注射,饲养1周适应环境,第2周开始进行暴露染尘与对照暴露生理盐水组实验,共暴露1、4、8周。采用口鼻暴露仓进行小鼠染尘与生理盐水暴露操作,每周暴露6d,每天2h,建立大气污染暴露荷瘤裸鼠模型,5只未做处理的Bac荷瘤裸鼠作为空白对照组。采集裸鼠晨起新鲜粪便样品,抽提其中微生物总基因组DNA,采用Ⅱ代基因测序技术对粪便样品进行16S高变区扩增测序,划分可操作分类单元(operational taxonomic unit,OTU),使用I-Sanger分析平台对所有OTU进行物种注释与评估、物种组成分析、样本比较分析等,运用R Studio软件对数据进行统计学分析。结果厚壁菌门和拟杆菌门在PM_(2.5)暴露组、生理盐水对照组和空白对照组均为最优势菌门。PM_(2.5)暴露组与生理盐水对照组及空白对照组相比厚壁菌门减少,拟杆菌门增加。结论 PM_(2.5)暴露减少Bac荷瘤裸鼠肠道菌群丰度,破坏肠道菌群平衡,在一定程度上可抑制有益菌的繁殖,并使致病菌数量增加。  相似文献   
937.
Huntington's disease (HD) is a neurodegenerative disorder caused by a mutation in the huntingtin gene. Previously, therapeutic approaches using anti-inflammatory agents were reportedly not effective for preventing HD progression. Since whether immune responses contribute to the onset of HD is not entirely understood, we herein investigated the role of immune activation in HD using the R6/2 transgenic (Tg) HD model mouse. IL12 production and the expression of costimulatory molecules (e.g. CD86 and CD40) on innate immune cells (DCs and macrophages) were diminished in the disease stage of R6/2 Tg mice. Moreover, the number of adaptive T cells (CD4+ and CD8+ T cells) and the frequency of effector memory phenotype CD4+ T cells were decreased in these mice. These results suggest that the severity of HD is closely related to an impaired immune system and might be reversed by activation of the immune system. Since lipopolysaccharide (LPS), a potent TLR4 agonist, activates immune cells, we evaluated the effect of immune activation on the pathogenesis of HD using LPS. The repeated immune activation with low-dose LPS significantly recovered the impaired immune status back to normal levels and attenuated both severe weight loss and the increased clasping phenotype found in the disease stage of R6/2 Tg mice, consequently resulting in prolonged survival. Taken together, these results strongly indicate that immune activation has beneficial influences on alleviating HD pathology and could provide new therapeutic strategies for HD.  相似文献   
938.
Females are often believed to actively choose highly ornamented males (males with extravagant morphological signals or intense sexual display), and ornaments should be honest signals of male viability. However, this belief is relying only on some pieces of empirical evidence from birds. Our study reports active female choice on sexual display that indicates male viability in spiders. We established trials in which we studied female choice in relation to male courtship drumming activity and body size. Females chose the most actively drumming males as mating partners, but the body size of the males did not seem to be selected. Male drumming activity turned out to be a good predictor of male viability, whereas male viability was independent of male body mass. Our results suggest that by actively choosing mates according to male drumming performance, but independently of male body mass, females are preferring viable males as mates. Because Hygrolycosa rubrofasciata males do not provide obvious direct benefits to their offspring, females may gain some indirect benefits; offspring may have higher chance of survival, or the offspring may inherit the attractiveness of their father.  相似文献   
939.
For many years, zinc salts have been used both topically and orally to treat minor burns and abrasions as well as to enhance wound repair in man and animals. In this study we describe the protective effects of zinc against UV-induced genotoxicity in vitro and against sunburn cell formation in mouse skin in vivo. Cultured skin cells from neonatal mice showed a dramatic increase in the number of micronuclei as a result of UVA and UVB irradiation. Inclusion of zinc at 5 μg/mL in the medium significantly reduced the frequency of micronuclei and of micronucleated cells. In hairless mice, topical application of zinc chloride for 5 consecutive days or a single application 2 h prior to UV exposure reduced the number of sunburn cells in the epidermis as did application of zinc 1 h after exposure. Application 2 h after irradiation also tended to have a protective effect, although there was a large variation between animals. It is proposed that an influx of zinc can protect epidermal cells against some of the more delayed effects of UV-induced damage.  相似文献   
940.
The oocytes of LT/Sv strain mice are unique in that a high proportion of them (∼40% in this study) are ovulated before reaching metaphase of the second meiotic division (metaphase II). The remaining oocytes of LT/Sv mice are ovulated at metaphase II, as in other strains of mice. When recently ovulated oocytes were cultured in vitro for 11–12 h, those ovulated at metaphase II remained at this stage, whereas those ovulated at metaphase of the first meiotic division (metaphase I) commonly resumed meiosis during in vitro aging. These oocytes extrude the polar body and form a diploid pronucleus. This oocyte activation is not coupled with cortical granule exocytosis. The oocytes ovulated at metaphase II are fully capable of normal fertilization, whereas those ovulated at metaphase I are not. Approximately 50% of metaphase I oocytes penetrated by spermatozoa remain at this stage, and sperm nuclei frequently undergo premature chromosome condensation. Only 13% of spermpenetrated metaphase I oocytes formed a diploid female pronucleus and a haploid male pronucleus by 4 h after insemination. These results demonstrate that the two types of ovulated LT/Sv oocytes have different potentials to undergo either spontaneous or sperm-induced activation.  相似文献   
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