中国汉族人群hGSTA1基因C-69T多态性分析

目的　研究中国汉族人群中人谷胱甘肽S 转移酶(hGSTA1 )C-69T基因多态性的分布。方法1 4 0例血样本来自中国2 5个省份的汉族人口,用聚合酶链反应 限制性片段长度多态性方法检测hGSTA1 69位点的变异。结果　中国汉族人群GSTA1基因 69位点的野生型纯合子(CC)基因型的分布频率为75 .0 %,突变型纯合子(TT)基因型为0 .7%,杂合子(CT)基因型为2 4 .3 %;C及T两种等位基因的频率分别为87.1 %及1 2 .9%。结论中国汉族人群GSTA1基因呈多态性分布,其等位基因和基因型频率不同于其他种族     

重组人表皮生长因子对大鼠宫颈鳞状上皮细胞体外增殖的影响

目的　研究重组人表皮生长因子(rhEGF)是否促进大鼠宫颈鳞状上皮细胞(RCEC)增殖及有关机制。方法　分离培养RCEC并用免疫组织化学技术鉴定细胞纯度;MTT法检测细胞增殖;流式细胞术分析细胞周期;逆转录聚合酶链反应检测细胞周期蛋白D1(cyclinD1)mRNA表达水平。结果　rhEGF刺激RCEC的增殖呈时间及剂量依赖性,且明显提高S期细胞分数。rhEGF 0 .1,1.0 ,10和10 0 μg·L- 1明显提高cyclinD1mRNA表达,以10 μg·L- 1于d 3的作用最强,最高可达5 0 .7%。结论　rhEGF对RCEC有促进增殖的作用,其机制与增强cyclinD1mRNA表达,以及刺激细胞从G0 /G1期进入S期有关。     

川芎嗪对顺铂肾损伤大鼠肾细胞凋亡及凋亡相关蛋白表达的影响

目的探讨川芎嗪(TMP)对顺铂(DDP)大鼠肾毒性有无保护作用。方法DDP8mg·kg-1ip诱导大鼠肾损伤,于给予DDP2d前大鼠分别ip50,100mg·kg-1·d-1TMP,连续5d,于给药d5收集各组大鼠尿液,测24h尿蛋白含量,并于末次给药后4h处死大鼠,测血清尿素氮(BUN)和肌酐(Cr)含量,采用原位缺口末端标记法检测肾脏细胞凋亡,免疫组化SP法检测肾脏Bax和Bcl2蛋白表达水平。结果50,100mg·kg-1TMP组可降低DDP所致大鼠24h尿蛋白及血清BUN和Cr含量的升高(P<0.01);TMP两剂量组也可明显减少肾脏细胞凋亡率(P<0.01),显著增强肾脏凋亡相关蛋白Bcl2的表达,减少Bax表达,并明显降低Bax/Bcl2比值(P<0.01)。结论TMP可能通过降低凋亡相关蛋白Bax和增强Bcl2的表达,并降低Bax/Bcl2比值而抑制DDP引起的肾细胞凋亡,使肾脏免受损伤的作用。     

氟伐他汀对心衰大鼠基质金属蛋白酶、转化生长因子及左室重构的影响

目的:了解基质金属蛋白酶-2(MMP-2)及转化生长因子-β1(TGF-β1)在心肌梗死大鼠左室重构及心衰发展过程中的改变,以及氟伐他汀的干预作用,探讨心梗后心衰的发生机制。方法:选用雄性SD大鼠67只随机分为假手术组、心梗组和心梗他汀组,经冠状动脉前降支结扎术建立心肌梗死后心衰模型,手术24 h后心梗他汀组大鼠管饲氟伐他汀4 mg·kg-1·d-1,假手术组和心梗组大鼠管饲安慰剂。术后3 d、4周、8周检测大鼠非梗死区心肌MMP-2的含量(Western-blot法)、胶原、TGF-β1的改变(免疫组化法),压力传感器记录左室血流动力学改变。结果:术后各时点非梗死区心肌的MMP-2含量,心梗组及心梗他汀组显著高于假手术组(P<0.05),而心梗他汀组显著低于心梗组(P<0.05);术后各组各时点非梗死区心肌TGF-β1表达的变化趋势与MMP-2相同;与心梗组比较,心梗他汀组术后4周和8周的心功能明显改善,胶原容积分数(CVF)及Ⅰ／Ⅲ型胶原比值(Ratio of type Ⅰ／Ⅲ)降低(P<0.05)。结论:氟伐他汀通过减少非梗死区心肌MMP-2和TGF-β1的含量,而减轻心梗后非梗死区心肌胶原网络的破坏及反应性胶原的过度沉积,从而预防和逆转心室重构,改善心脏功能。     

In utero exposure to tobacco and alcohol modifies neurobehavioral development in mice offspring: consideration a role of oxidative stress.

OBJECTIVE: To determine whether in utero tobacco and alcohol exposure induces long-term neurobehavioral alterations and whether oxidative stress/damage is a possible causal factor. METHODS: Gravid mice were subjected to tobacco smoking and alcohol consumption. Their offspring were subsequently evaluated in developmental and behavioral tests. Antioxidative enzymes and erythrocyte membrane fluidity of adult offspring were measured. RESULTS: The intrauterine tobacco and alcohol exposure has resulted in significant reduced postnatal body and organ weights accompanied by reduced gestational body weight gain in their mothers. Such exposure also induced remarkable developmental delay in neonatal reflexes and notable behavioral deficit in adulthood, namely reduced motive coordination and locomotor activity as well as impaired learning and memory abilities. Furthermore, the formation of malondialdehyde (MDA) increased significantly whereas the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), catalase (Cat) and glutathione S-transferases (GST) decreased in the cerebral cortex and liver of prenatal intoxicated offspring. The embryonic intoxication also markedly reduced erythrocyte membrane fluidity in offspring. CONCLUSION: Our study shows the long-term neurotoxicity associated with prenatal tobacco and alcohol exposure, and suggests that the deleterious outcome may be in relation to increased free radicals formation and oxidative stress.     

Integrating the molecular and the population approaches to dementia research to help guide the future development of appropriate therapeutics

Dementia research over the last 50 years has expanded enormously and has greater international interest now than at any time in history. A variety of scientific approaches have been brought to bear on this complex disorder in which the syndrome of clinical features is its defining importance in societal terms. Little has emerged in terms of tangible benefits for people with dementia to date other than a hugely increased awareness at societal and governmental levels. One of the drivers for the increase in focus has been epidemiological evidence, which has provided background numbers for the justification of resources for dementia research. However it can be argued that this justification did not take into account the true meaning of the population evidence, drawing instead on preconceptions which were, at the time, the widely accepted interpretations of earlier evidence. Current evidence, along with the lack of single therapeutic successes, suggests that a clearer analysis is required which not only examines the value and applicability of existing knowledge, most particularly its generation and generalizability, but also where future investment should go for most likely benefit of populations. This includes a hard look at the pre-occupation of societies with single therapies, their place in the context of prevention more generally, particularly within aging populations, and how evidence is generated on likely impacts and their timeframes.     

Coxsackievirus-induced acute neonatal central nervous system disease model

Coxsackievirus B (CVB) is a significant pathogen that causes pediatric central nervous system disease with acute syndromes commonly. The onset of its infection was abrupt, and after recovery there usually will be severe mental sequelae. The disease model for research was not established by the way of natural infection, although there are various investigations about the CVB-induced central nervous system (CNS) diseases. Thus, we have established an acute neonatal CNS disease mice model by CVB orally infecting. This model imitated the natural infection route and focuses the onset of CNS disease, inducing severe infection and lesion in the hippocampus and cortex regions, and the stability of the model was demonstrated. A pathology score system was developed for quantitative pathology analysis, which standardizes the CNS pathology analysis by statistics analysis. By this model, the track of CVB penetrating the blood brain barrier in vivo has been captured. One of the experimental strains CVB3/Macocy, as a new variant, was isolated, and its genomic RNA was cloned. According to its nucleotide sequence, we have characterized its genomic structure and defined its genotype. Based on the sequence, some mutations which do not change the CVB-induced CNS damage have been found. The model is an effective tool for studies on CVB-induced CNS diseases.     

The Tension and Puncture Properties of HDPE Geomembrane under the Corrosion of Leachate

To investigate the gradual failure of high-density polyethylene (HDPE) geomembrane as a result of long-term corrosion, four dynamic corrosion tests were conducted at different temperatures and durations. By combining tension and puncture tests, we systematically studied the variation law of tension and puncture properties of the HDPE geomembrane under different corrosion conditions. Results showed that tension and puncture failure of the HDPE geomembrane was progressive, and tensile strength in the longitudinal grain direction was evidently better than that in the transverse direction. Punctures appeared shortly after puncture force reached the puncture strength. The tensile strength of geomembrane was in inversely proportional to the corrosion time, and the impact of corrosion was more obvious in the longitudinal direction than transverse direction. As corrosion time increased, puncture strength decreased and corresponding deformation increased. As with corrosion time, the increase of corrosion temperature induced the decrease of geomembrane tensile strength. Tensile and puncture strength were extremely sensitive to temperature. Overall, residual strength had a negative correlation with corrosion time or temperature. Elongation variation increased initially and then decreased with the increase in temperature. However, it did not show significant law with corrosion time. The reduction in puncture strength and the increase in puncture deformation had positive correlations with corrosion time or temperature. The geomembrane softened under corrosion condition. The conclusion may be applicable to the proper designing of the HDPE geomembrane in landfill barrier system.