同型半胱氨酸水平与脑梗死患者MTHFR基因C677T多态性之间的相关性研究

目的 探讨研究同型半胱氨酸（homocysteine,Hcy）水平与脑梗死患者亚甲基四氢叶酸还原酶（MTHFR）基因C677T的多态性之间的相关性。方法 选择2012年2月~2015年8月期间在笔者医院住院就诊的450例脑梗死患者作为研究组,其中糖尿病患者181例,非糖尿病患者269例,另外选择285例笔者医院门诊部健康的体检人员作为对照组,分别采用焦磷酸测序的方法检测分析MTHFR基因C677T的多态性,并分析各基因型与Hcy水平之间的相关性。结果 脑梗死组与健康对照组的MTHFR基因型分布之间的差异具有统计学意义（P<0.05）,脑梗死组T基因的频率明显比对照组高,差异有统计学意义（χ²=13.67,P=0.00）。脑梗死组患者的Hcy浓度明显高于健康对照组,差异有统计学意义（t=12.71,P=0.00）。脑梗死组患者各MTHFR基因型患者的Hcy水平之间比较,差异有统计学意义（F=17.68,P=0.00）。非糖尿病脑梗死患者的Hcy水平明显高于糖尿病脑梗死患者,差异有统计学意义（t=2.97,P=0.00）,非糖尿病组TT型的Hcy浓度明显高于糖尿病组,CC型的Hcy浓度明显低于糖尿病组,差异均有统计学意义（t=5.67,2.18;P=0.00,0.03）。糖尿病性脑梗死患者和非糖尿病脑梗死患者中,MTHFR基因为TT型的Hcy水平明显高于CC型和CT型,差异均有统计学意义（P<0.05）,而CC型和CT型的Hcy水平之间比较差异无统计学意义（P>0.05）。结论 脑梗死患者比健康人的MTHFR基因C677T的T等位基因频率高,且脑梗死患者的MTHFR基因C677T为TT基因型时血清中Hcy的水平更高,由此判断TT基因型可能是脑梗死发生的危险因素。     

卵磷脂对花尾胡椒401幼鱼谷肤甘肤一硫一转移酶，谷肤甘肤过氧化物酶和DNA完整性的影响

采用不同卵磷脂添加量的配合饲料投喂花尾胡椒鲷(Plectorhyncchus cinctus）幼鱼，同步测定幼鱼的谷胱甘肽-硫-转移酶和谷胱甘肽过氧化物酶活性以及DNA完整程度。结果表明，谷胱甘肽-硫-转移酶和谷胱甘肽过氧化物酶活性随着饲料中卵磷脂含量的增加而提高，而DNA单链断裂程度随着饲料中卵磷脂含量的增加而减少。这提示卵磷脂能够提高鱼体的抗氧化防御系统的机能。     

温度对南极衣藻ICE-L(Chlamydomonas sp. ICE-L)谷胱甘肽含量及其相关酶活性的影响

采用分光光度法研究了在不同温度下(包括最适温度、低于或高于最适温度)南极衣藻ICE-L(Chlamydomonassp.ICE-L)谷胱甘肽(GSH)含量、蛋白含量、谷胱甘肽过氧化物酶(GPx)、谷胱甘肽还原酶(GR)和谷胱甘肽硫转移酶(GST)活性,同时分析了已适应高温(16℃)的衣藻重新适应低温(8℃)时这些指标的变化,以期阐明谷胱甘肽系统与南极冰藻低温适应性的关系。结果表明,当温度低于对照组(最适温度8℃)时,蛋白含量降低,而GSH含量、GPx、GST和GR活性上升,已适应高温的衣藻重新适应低温时也出现类似的结果。但当温度高于最适温度时,GSH含量、GST和GPx活性下降,而蛋白含量和GR活力有上升的趋势,GR活力增长幅度比低于最适温度时的变化小。由此可见谷胱甘肽系统在南极衣藻低温适应过程中,GSH、GPx、GR、GST与低温适应呈正相关,同时除GR外其他因子与南极衣藻高温适应呈负相关,GSH及其相关酶在南极冰藻低温适应中具有重要作用。     

斑节对虾GPx3a基因的分子克隆及表达分析

谷胱甘肽过氧化物酶(Glutathione peroxidase,GPx)是生物体内重要的抗氧化酶,能防止过氧化氢对生物体的氧化应激。该研究利用RACE技术获得了斑节对虾(Penaeus monodon)GPx3a(PmGPx3a)的全长c DNA序列,进行了相关生物信息学分析。作者利用荧光定量PCR方法研究了PmGPx3a在斑节对虾不同组织的表达情况。探究了PmGPx3a在不同胁迫条件下(盐度、重金属和细菌)的表达情况。结果表明PmGPx3a c DNA全长1135 bp,其中开放阅读框(ORF)长651 bp,预测编码216个氨基酸。PmGPx3a推导的氨基酸序列与其他动物的GPx3a氨基酸序列具有高度一致性。实时定量PCR结果显示,在高低盐胁迫下,PmGPx3a在肝胰腺中相对表达量都为上升的(p0.05)。在铜、锌、铬胁迫中,鳃中的PmGPx3a的相对表达量总体呈现下降趋势,在肝胰腺中呈现上升趋势。在哈维弧菌(Vibrio harveyi)刺激下,PmGPx3a在血淋巴中的相对表达量总体呈现上升趋势,24 h后表达量最大,显著高于对照组2.2倍(P0.05)。以上研究结果表明,PmGPx3a基因参与了斑节对虾对环境胁迫和氧化应激的适应性反应。     

大叶藻微粒体GST基因对温度胁迫响应的分子机制

为了分析鳗草（Zostera marina）中微粒体谷胱甘肽S-转移酶在不同温度下的基因表达规律以及响应机制，本文通过在大肠杆菌中表达ZmGST，纯化重组蛋白以及热稳定性分析，以此为进一步阐述Z. marina的种群退化机制并提供理论依据。总之，鳗草中的微粒体GST的热稳定性和其对温度变化的响应决定了其对温度的耐受范围，并进而影响其恢复力。     

Comparative study on in vitro transformation of paralytic shellfish poisoning (PSP) toxins in different shellfish tissues

Dissected tissues of three shellfish species,the Chinese scallop,Chlamys farreri,Manila clam,Ruditapes philippinarum,and Razor shell,Solen strictu were evaluated for in vitro transformation of paralytic shellfish poisoning(PSP) toxins. Tissue homogenates were incubated with extraction from toxic algae Alexandrium minutum to determine toxin conversion. The effects of heating and addition of a natural reductant(glutathione) on toxin conversion were also assessed. The toxin profile was investigated through high performance liquid chromatography with fluorescence detection(HPLC-FLD) . The evident variations in the toxin content were observed only in Chinese scallop viscera homogenates. The concentration of GTX4 was reduced by 45%(approximately 0.8 μmol/dm 3 ) and 25%(approximately 1 μmol/dm 3 ) for GTX1,while GTX2 and GTX3 increased by six times(approximately 1 μmol/dm 3 ) and 3 times(approximately 0.3 μmol/dm 3 ) respectively. Simultaneously,the total toxicity decreased by 38% during the 48 h incubation period,the final toxicity was 20.4 nmol STXeq/g. Furthermore,heated Chinese scallop viscera homogenates samples were compared with non-heated samples. The concentration of the GTX4 and GTX1 was clearly 28%(approximately 0.53 μmol/dm 3 ) and 17%(approximately 0.69 μmol/dm 3 ) higher in heated samples,GTX2 and GTX3 were four times(0.66 μmol/dm 3 ) and two times(0.187 μmol/dm 3 ) lower respectively. GSH(+) Chinese scallop viscera homogenates samples were compared with GSH(-) samples,the concentration in the GTX4 and GTX1 was 9%(approximately 0.12 μmol/dm 3 ) and 11%(approximately 0.36 μmol/dm 3 ) lower respectively,GTX2 and GTX3 was 17%(approximately 0.14 μmol/dm 3 ) and 19%(approximately 0.006 μmol/dm 3 ) higher respectively. In contrast,there was a little change in the concentration of PSP toxins of Manila clam and Razor shell tissue homogenates. These observations on three shellfish tissues confirmed that there were species-specific differences in PSP toxins transformation. PSP toxins transformation was more pronounced in viscera tissue than in muscle tissue. PSP toxins was possibly interfered by some carbamoylase enzyme,and the activity in Chinese scallop viscera tissue is more remarkable than in the other two species.     

温度和盐度对华贵栉孔扇贝免疫相关酶的联合效应

为研究温度和盐度对华贵栉孔扇贝免疫相关酶活力的联合效应,采用中心复合设计(CCD)和响应曲面分析法(RSM)进行试验,在实验室条件下研究了温度(19~31℃),盐度(22~38)对华贵栉孔扇贝酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、谷胱甘肽还原酶(GR)三种免疫相关酶活性的联合效应,旨在考察温度与盐度对ACP,AKP和GR活性的影响及华贵栉孔扇贝免疫水平较高时的最佳温度和盐度组合,为华贵栉孔扇贝人工养殖所需条件提供理论基础。结果表明:温度的一次效应和二次效应对ACP,AKP和GR活力影响显著(P0.05);盐度的一次效应和二次效应对ACP,AKP和GR的活力影响显著(P0.05);温度和盐度的交互作用对ACP,AKP和GR活力的影响显著(P0.05)。采用响应曲面法,建立了温度和盐度对华贵栉孔扇贝ACP,AKP和GR活性影响的模型方程,该模型方程决定系数分别为0.986 6,0.981 3和0.957 6(P0.01),预测系数分别为0.934 5,0.888 0和0.738 4,表明该模型可以用于预测华贵栉孔扇贝ACP,AKP和GR活力变化。通过模型优化和验证实验,得到在温度24.30℃、盐度30.55时,ACP和AKP活力达到最小值,分别为170.43,181.74U/mg,而GR活力最大为0.34U/mg,满意度达0.95。     

Influence of temperature on glutathione level and glutathione-related enzyme activities of Antarctic ice microalgae Chlamydomonas sp.ICE-L

GSH system plays a role in the control of the redox balance state,anti-oxidation and protecting life from injury of ROS(reactive oxygen species).In present paper,the possible GSH system of Chlamydomonas sp.ICE-L has been investigated by evaluating GSH and GSH-related enzymatic responses at different temperatures using spectrophotometer methods.The results showed that the GSH system is correlated positively to low temperature,and other factors but GR are correlated negatively to high temperature.So GSH and GSH-related enzymes play an important role in the adaptation of Antarctic ice microalgae to low temperature.     

菲律宾蛤仔(Venerupis philippinarum)Rho型GST和微粒体型GST的序列分析及表达特征研究

谷胱甘肽硫转移酶是一类在细胞解毒和抗氧化过程中发挥重要作用的超家族酶系。采用cDNA末端快速扩增技术,从菲律宾蛤仔中克隆获得Rho型GST和微粒体型GST基因的全长序列(分别命名为VpGSTR和VpGSTMi)。序列分析显示,VpGSTR和VpGSTMi的cDNA全长分别为942bp和661bp,编码234和149个氨基酸。系统分析结果表明,菲律宾蛤仔GSTR与GSTMi在进化树上的位置与其分类所处的位置一致。荧光定量PCR结果发现,VpGSTR和VpGSTMi广泛分布于所检测组织中,且在肝胰腺组织中表达量最高。在鳗弧菌侵染后,VpGSTR和VpGSTMi基因表达量在24h内均表现出明显的上升趋势。上述结果表明,VpGSTR和VpGSTMi可能在菲律宾蛤仔抵御细菌侵染导致的氧化应激中发挥重要功能。     

南极衣藻（Chlamydomonas sp.ICE-L）谷胱甘肽还原酶基因的原核表达及其条件优化

采用RT-PCR技术克隆南极衣藻GR基因ORF全长cDNA,然后经酶切、连接等步骤构建其原核表达载体;并对其表达的诱导时间、IPTG浓度、温度进行了优化,以期获得较大量的酶蛋白。结果表明,将构建的原核表达载体pET-GR导入大肠杆菌BL21,可以高效表达融合蛋白;且表达的蛋白均以包涵体的形式存在;经SDS-PAGE电泳...