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851.
Consumption of fructose has been linked to the development of metabolic syndrome, whereas the cardiomyopathic changes and cardiac apoptosis of dietary high‐fructose intake have not yet been clarified. The purpose of this study was to evaluate the effects of high‐fructose on cardiac apoptotic and survival pathways. Thirty‐two Wistar rats were randomly divided into a control group (CON), which received a standard chow diet, and a fructose‐induced metabolic syndrome group (FIMS), which received a 50% fructose‐content diet for 13 weeks. Histopathological analysis, TUNEL assays and Western blotting were performed on the excised hearts from both groups. The blood pressure, glucose, insulin, triglyceride and cholesterol levels were significantly increased in the FIMS group, compared with the CON group. The abnormal myocardial architecture, enlarged interstitial space and increased cardiac TUNEL‐positive apoptotic cells were observed in the FIMS group. The TNF‐α, TNF receptor 1, Fas ligand, Fas receptor, FADD, and activated caspase‐3 and 8 protein levels (Fas pathway) and the Bax, Bak, Bax/Bcl‐2, Bak/Bcl‐xL, cytosolic cytochrome c, and activated caspase‐3 and nine protein levels (mitochondria pathway) were increased in the FIMS group compared with those in the CON group. The IGFI, IGFI‐R, p‐PI3K, p‐Akt, Bcl‐2 and Bcl‐xL protein levels (survival pathway) were all significantly decreased in the FIMS group compared with those in the CON group. High‐fructose intake elevated blood pressure and glucose levels; moreover, high‐fructose diet activated cardiac Fas‐dependent and mitochondria‐dependent apoptotic pathways and suppressed the survival pathway, which might provide one possible mechanism for developing heart failure in patients with metabolic syndrome. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
852.
853.
巴斯德毕赤酵母(Pichia pastoris)表达系统已成为外源蛋白最理想的表达系统之一,诸多的优点体现了其广泛的研究价值和应用价值。综述了P.pastoris表达外源蛋白时在载体选择与利用、外源基因改造、翻译后修饰及表达稳定性等方面的优化策略,以加速其应用。  相似文献   
854.
酵母基因组共表达基因簇与其上游顺式作用元件的关系   总被引:1,自引:0,他引:1  
DNA微阵列技术的快速发展开辟了从表达图谱研究基因组功能的新途径。酵母全基因组的测定和基因组表达图谱数据的发表使其成为研究真核基因转录调控机制的首选目标。运用生物信息学的工具研究了酵母基因组中基因上游顺式调控元件与基因组表达图谱的关系。结果表明,表达紧密关系的同一簇基因都具有若干特异的顺式作用元件,其表达受到相应反式调控因子的控制。找到的位点中,一部分与已知顺式作用元件相对应;另一部分可能是新的顺  相似文献   
855.
采用基因表达谱可以研究基因功能模块与疾病异质性之间的关系.根据两套白血病基因表达谱数据,将富集高变异基因的Gene Ontology基因功能模块作为特征功能模块,将疾病样本聚为两类.通过对比原始多类标签,采用聚类评估指标来分析两类化聚类结果的效果,并探讨特征功能模块与疾病异质性之间的关系.实验结果显示:在两套不同的白血病基因表达谱数据中得到的特征功能模块类似,它们对白血病亚型有较强的分型能力.  相似文献   
856.
魏娜  唐焕新  杨雪梅  冯力  吴蔚  佟达 《生物磁学》2013,(35):6933-6936
目的:探讨参麦注射液用于治疗慢性呼吸衰竭急性加重患者的临床效果。方法:选取2011年3月.2012年6月在我愿接受治疗的慢性呼吸衰竭急性加重的患者68例,随机分为参麦组和对照组,每组各34例。对照组采取常规方法进行治疗,参麦组在此基础上给予参麦注射液加以治疗。观察并比较两组患者的治愈率、住院时间、肺功能指标(FEVl)及血气分析情况等相关指标。结果:参麦组的治愈率为91.18%,与对照组的53.12%相比较,差异显著(X^2=10.8800,P〈0.05)。参麦组的住院时间显著短于对照组,其肺功能指标、血气分析结果包括氧分压值和二氧化碳分压值均明显优于对照组,具有统计学意义(P〈0.05)。结论:参麦注射液治疗慢性呼吸衰竭急性加重疾病不失为一种优良的治疗方案,不仅患者临床症状得到明显的改善,病情好转加快,还可以调节患者的免疫力,在临床上值得推广。  相似文献   
857.
In Chinese hamster ovary (CHO) cells, rapid glucose metabolism normally leads to inefficient use of glucose, most of which is converted to lactate during cell cultures. Since lactate accumulation during the culture often exerts a negative effect on cell growth and valuable product formation, several genetic engineering approaches have been developed to suppress lactate dehydrogenase-A (LDH-A), the enzyme converting pyruvate into lactate. However, despite the reduced lactate accumulation, such cell cultures are eventually terminated in the late period of the culture, mainly due to apoptosis. Therefore, we developed an apoptosis-resistant, less lactate-producing dhfr CHO cell line (CHO-Bcl2-LDHAsi) by overexpressing Bcl-2, one of the most well-known anti-apoptotic proteins, and by downregulating LDH-A in a dhfr CHO cell line. When the dhfr CHO-Bcl2-LDHAsi cell line was used as a host cell line for the development of recombinant CHO (rCHO) cells producing an Fc-fusion protein, the culture longevity of the rCHO cells was extended without any detrimental effect of genetic engineering on specific protein productivity. Simultaneously, the specific lactate production rate and apparent yield of lactate from glucose were reduced to 21–65% and 37–78% of the control cells, respectively. Taken together, these results show that the use of an apoptosis-resistant, less lactate-producing dhfr CHO cell line as a host cell line saves the time and the effort of establishing an apoptosis-resistant, less lactate-producing rCHO cells for producing therapeutic proteins.  相似文献   
858.
我们用同源模建方法构建了江浙蝮蛇毒碱性-酸性杂合磷脂酶A2-Ⅱ和中性磷脂酶A2的三维结构,并对它们的结构特征做了比较分析。在此基础上,我们在三维结构水平上解释了磷脂酶A2荧光光谱学研究的一些结果。我们还对四种江浙蝮蛇毒磷脂酶A2的酶活性部位的静电势分布做了分析。我们认为:含钙的PLA2酶活性部位周围的静电势有利于PLA2与带负电荷的底物结合。  相似文献   
859.
青藏高原植被生长季NDVI时空变化与影响因素   总被引:7,自引:0,他引:7  
青藏高原是中国乃至亚洲的生态屏障,研究其植被对气候变化的响应对区域生态保护具有重要的现实意义.基于MOD09A1数据反演的生长季归一化植被指数(NDVI),分析2001-2018年青藏高原植被生长季NDVI时空特征和变化趋势,结合气象站点数据阐释NDVI与气候因子的关系.结果 表明:研究期间,青藏高原植被生长季NDVI...  相似文献   
860.
AimThis research aims to analyze the acute effect of incremental inspiratory loads on respiratory pattern and on the predominant activity frequency of inspiratory muscle, taking into account differences in gender responses. Optoelectronic Plethysmography was performed during loads in 39 healthy subjects (20 women), placing 89 markers on the thoracic-abdominal wall to obtain total and regional volumes. Surface electromyography (SEMG) was taken simultaneously on the Sternocleidomastoid and Diaphragm muscles, to calculate the predominant muscle activity frequency through wavelet analysis. Inspiratory loads were performed using Threshold® with 2 min of breathing at different levels, ranging from a load of 10 cmH2O plus 5 cmH2O to 40 cmH2O or fatigue.ResultsInspiratory Time increased during loads. Total and compartmental volumes increased with different regions, changing at different loads. These changes in volume occur earlier in women (20 cmH2O) than in men (30 cmH2O). The predominant activity frequency of Sternocleidmastoid muscle decreased at 30 cmH2O, while Diaphragm activity decreased at 40 cmH2O.ConclusionThe acute effects of incremental inspiratory loads are increases of total and regional volumes and inspiratory time. As for muscle activity, the predominant activity frequency declined in Sternocleidomastoid and Diaphragm muscles, but at different loads. Such respiratory and SEMG patterns and gender differences should be considered when clinical interventions are performed.  相似文献   
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