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31.
Pink 1基因编码定位于线粒体上的丝/苏氨酸激酶(即PARK6),为常染色体隐性遗传性帕金森病(Parkinsons disease, PD)连锁的基因.该基因在遗传性和散发性PD的发病中起重要作用,但其发病机理尚未明确.本研究以近交系C57BL/6J (B6) 和DBA/2J (D2)小鼠制作MPTP诱导的PD鼠为模型,借助基因表达数量性状基因座(eQTL),结合分子生物学方法,分析Pink1的表达调控.结果显示,Pink 1基因在PD模型组中表达显著升高.区间连锁分析检测显示,引起Pink 1基因表达水平差异的染色体区域,定位于4号染色体上,距Pink 1基因自身5 Mb范围之类,属于顺式调节eQTL.Pearson相关分析表明,在BXD 基因重组近交系(recombinant inbred,RI)小鼠脑中,Camk2n等30个基因的表达与Pink 1基因高度相关,相互间可能存在一定的协同作用.Pink 1基因在行使特定生物学功能时,很可能协同这些基因一起发挥相应的作用,这部分基因是深入研究Pink 1基因在PD发病中分子机制的重要靶点.  相似文献   
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Oxytocin (OT) is essentially associated with uterine contraction during parturition and milk ejection reflex. Although several studies implicate the role of OT in anti-inflammatory, anti-oxidative and anti-apoptotic pathways, there is a lack of data with regard to the protective effects of oxytocin in neurodegenerative models such as Parkinson's disease (PD). The present study was undertaken to investigate the neuroprotective effects of oxytocin (OT) on rotenone-induced PD in rats. Twenty adult Sprague-Dawley rats were injected with rotenone (3 μg/μl in DMSO) or vehicle (1 μl DMSO) into the left substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) under stereotaxic surgery, and PD model was assessed by rotational test ten days after drug infusion. The valid PD rats were randomly divided into two groups; Group 1 (n = 7) and Group 2 (n = 7) were administered saline (1 ml/kg/day, i.p.) and oxytocin (160 μg/kg/day, i.p.) through 20 days, respectively. The effects of OT treatment were evaluated by behavioral, histological and immunohistochemical parameters. Apomorphine-induced stereotypic rotations in PD rats were significantly inhibited by OT treatment (p < 0.05). In addition, immunohistochemical studies clearly demonstrated the suppression of Bax, caspase-3, caspase-8 and elevation of Bcl-2 and tyrosine hydroxylase immunoexpression in OT-treated rats compared to saline group. Our findings suggest that oxytocin may have cytoprotective and restorative effects on dopaminergic neurons against rotenone-induced injury. The underlying mechanism may be associated with the inhibition of apoptotic pathways.  相似文献   
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The MTHFR is a candidate risk gene for Parkinson's disease (PD), and a functional SNP (rs1801133) in the coding region of this gene has been investigated for the associations with the illness extensively among worldwide populations, but overall the results were inconsistent. Here, to assess the relationship between rs1801133 and risk of PD in general populations, we conducted a systematic meta-analysis by combining all available case–control samples in European and Asian populations, with a total of 1820 PD cases and 7530 healthy controls, and the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) for rs1801133 and PD were calculated using the Mantel–Haenszel method with a fixed-effect model. Overall, rs1801133 was significantly associated with the risk of PD (allelic model, pooled OR = 1.212 for T allele, 95% CI = 1.097–1.340, p-value = 0.0002). When stratifying for ethnicity, significant association was also observed in European (allelic model, pooled OR = 1.187 for T allele, 95% CI = 1.058–1.332, p-value = 0.004) and Asian samples (allelic model, pooled OR = 1.293 for T allele, 95% CI = 1.058–1.580, p-value = 0.012) respectively. In addition, rs1801133 was also significantly associated with MTHFR mRNA expression in both CEU (European, p-value = 0.0149) and CHB (Chinese, p-value = 0.0178) HapMap populations. Collectively, our meta-analysis suggests that rs1801133 is significantly associated with susceptibility to PD in European and Asian populations, and MTHFR is likely an authentic risk gene for PD.  相似文献   
36.
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity.  相似文献   
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Titanium (IV) and vanadium (V) complexes are highly potent anticancer agents. A challenge in their synthesis refers to their hydrolytic instability; therefore their preparation should be conducted under an inert atmosphere. Evaluation of the anticancer activity of these complexes can be achieved by the MTT assay.The MTT assay is a colorimetric viability assay based on enzymatic reduction of the MTT molecule to formazan when it is exposed to viable cells. The outcome of the reduction is a color change of the MTT molecule. Absorbance measurements relative to a control determine the percentage of remaining viable cancer cells following their treatment with varying concentrations of a tested compound, which is translated to the compound anticancer activity and its IC50 values. The MTT assay is widely common in cytotoxicity studies due to its accuracy, rapidity, and relative simplicity.Herein we present a detailed protocol for the synthesis of air sensitive metal based drugs and cell viability measurements, including preparation of the cell plates, incubation of the compounds with the cells, viability measurements using the MTT assay, and determination of IC50 values.  相似文献   
38.
The catabolic process of macroautophagy, through the rapid degradation of unwanted cellular components, is involved in a multitude of cellular and organismal functions that are essential to maintain homeostasis. Those functions include adaptation to starvation, cell development and differentiation, innate and adaptive immunity, tumor suppression, autophagic cell death, and maintenance of stem cell stemness. Not surprisingly, an impairment or block of macroautophagy can lead to severe pathologies. A still increasing number of reports, in particular, have revealed that mutations in the autophagy-related (ATG) genes, encoding the key players of macroautophagy, are either the cause or represent a risk factor for the development of several illnesses. The aim of this review is to provide a comprehensive overview of the diseases and disorders currently known that are or could be caused by mutations in core ATG proteins but also in the so-called autophagy receptors, which provide specificity to the process of macroautophagy. Our compendium underlines the medical relevance of this pathway and underscores the importance of the eventual development of therapeutic approaches aimed at modulating macroautophagy.  相似文献   
39.
Chung SC  Kim TI  Ahn CH  Shin J  Oh KB 《FEBS letters》2010,584(22):4639-4645
Farnesoic acid is a signaling molecule that inhibits the transition from budding yeast to filament formation in Candida albicans, but the molecular mechanism regulated by this substance is unknown. In this study, we analyzed the function of CaPHO81, which is induced by farnesoic acid. The pho81Δ mutant cells existed exclusively as filaments under favorable yeast growth conditions. Furthermore, the inhibition of hyphal growth and repression of CPH1, EFG1, HWP1, and GAP1 mRNA expression in response to farnesoic acid were defective in pho81Δ mutant cells. These data suggest a role for CaPHO81 in the inhibition of hyphal development by farnesoic acid.  相似文献   
40.
帕金森病(Parkinson’s disease,PD)是一种常见于中老年的神经退行性疾病,其特征性的病理改变为黑质纹状体多巴胺能神经元选择性缺失以及胞浆内涵物Lewy小体的形成。PD的发病机制目前尚不清楚,但已经明确环境因素和遗传因素在PD的发病中起重要作用。为阐明PD的病理生理机制,进一步探索新的治疗手段,迫切需要与PD密切相似的模型。本文将就目前发展的各种PD模型做一综述。  相似文献   
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