Wnt在胰岛素抵抗大鼠海马Aβ沉积中的作用及罗格列酮治疗前后Aβ的变化

目的: 探讨经典Wnt通路中的配体Wnt3a及下游胞内的β-catenin与胰岛素抵抗(IR)大鼠模型海马中β淀粉样肽(Aβ)沉积的关系;观察IR模型大鼠经罗格列酮治疗后,上述各指标的改变及与过氧化物酶体增殖物激活受体-γ(PPARγ)的相关性。方法: 高糖、高脂、高蛋白饮食3个月造IR大鼠模型(IR),给予罗格列酮灌胃4周为治疗组(TZD);葡萄糖氧化酶法检测大鼠血糖水平,放免法检测血浆胰岛素水平,HOMA-IR评估胰岛素抵抗水平,蛋白印迹技术检测大鼠海马内Aβ、Wnt3a、β-catenin及PPARγ的水平。结果: IR组血浆胰岛素水平及胰岛素抵抗程度显著高于对照组。免疫印迹结果显示,IR组大鼠海马中Aβ及β-catenin表达增加,Wnt3a及PPARγ表达明显减少;经TZD干预后,大鼠海马中Aβ表达减少,Wnt3a、β-catenin及PPARγ表达增加。结论: 胰岛素抵抗大鼠海马内Wnt信号通路水平下降可能是导致Aβ沉积的原因。罗格列酮作为PPARγ激动剂,可通过上调Wnt通路活性从而减少IR大鼠海马内Aβ的沉积。     

c-Jun氨基末端激酶在脑缺血再灌注损伤中的作用

在生物体内,丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)是信号从细胞表面转导至细胞核内部的重要传递者,是一类丝/苏氨酸残基的蛋白激酶。目前在真核生物细胞中,已明确了4条MAPK信号转导通路,即细胞外信号调节蛋白激酶(extracellular signal-regulated protein kinases,ERK)通路、c-Jun氨基末端激酶(c-Jun N-terminal kinase,JNK)通路、p38通路及ERK5通路。JNK信号通路作为MAPK信号通路中重要的通路之一,参与了多种生理、病理过程,目前诸多研究表明其在脑缺血/再灌注损伤过程中尤其是程序性细胞死亡过程中起着重要的调控作用,本文就近年来对JNK通路的研究及JNK在脑缺血再灌注诱导的细胞凋亡中的作用及机制作一综述。     

幽门螺杆菌VacA N端片段通过线粒体途径诱导GES-1细胞凋亡

目的:本研究初步探讨幽门螺杆菌(H.pylori)空泡毒素单一毒力决定簇对GES-1胃黏膜上皮细胞凋亡的影响,为进一步研究H.pylori的致病机制奠定基础。方法:将本课题组已构建的pDsRed-Monomer-C1/VacA N端真核表达载体转染至GES-1细胞中,Western blot鉴定VacA蛋白在细胞中的表达;电子显微镜和中性红摄取试验检测GES-1细胞的空泡样变;Hoechst33342染色、Annexin V-FITC凋亡检测试剂盒以及电镜观察细胞凋亡情况,同时采用分光光度法检测细胞Caspase-9、Caspase-3的活化程度,Rho123检测细胞跨膜电位的变化,ELISA法检测细胞色素C的释放。结果:重组质粒pDsRed-Monomer-C1/VacA转染GES-1细胞24小时后,电镜下可明显观察到空泡样变及核固缩、染色质边聚等凋亡特征,重组质粒组部分细胞发生空泡样变;Hoechst 33342染色后镜下可见明显的核染色质浓缩,Annexin V-FITC凋亡检测试剂盒检测发现重组质粒组细胞凋亡率明显高于对照组(P<0.05);Caspase-9和Caspase-3活化程度呈时间依赖性增加,分别在12小时和24小时达到峰值;Rho123染色发现线粒体跨膜电位明显降低;重组质粒转染组释放细胞色素C的浓度呈时间依赖性正相关,与空质粒组及对照组相比差异显著(P<0.05)。结论:VacA N端片段可诱导GES-1细胞凋亡及空泡样变,VacA蛋白可激活Caspase-9和Caspase-3,且可能主要通过线粒体途径诱导GES-1细胞凋亡。     

ERK和P38MAPK升高MLC20磷酸化调节大鼠平滑肌低氧反应性

目的 研究丝裂原活化蛋白激酶(MAPK)亚类ERK、P38 MAPK和JNK在低氧血管平滑肌收缩反应性调节中的作用,并从肌球蛋白轻链(MLC20)磷酸化的钙敏感性调节途径上初步探讨其机制.方法 用低氧培养血管平滑肌细胞(VSMC)模型和大鼠失血性休克模型,用荧光法检测VSMC收缩反应,用Western blot检测血管...     

Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome

Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation.     

Phosphorylation and cytoplasmic localization of MAPK p38 during apoptosis signaling in bone marrow granulocytes of mice irradiated in vivo and the role of amifostine in reducing these effects

We studied p38 phosphorylation and its intracellular localization during p53 and Puma (a p53 upregulated modulator of apoptosis) apoptotic signaling pathway in bone marrow granulocytes in mice irradiated in vivo and the role of the radioprotector amifostine in ameliorating these responses. Sixty-four C57BL mice were randomly assigned in two non-irradiated (Ami−/rad− and Ami+/rad−) and two irradiated (Ami−/rad+ and Ami+/rad+) groups. Animals received 400 mg/kg of amifostine i.p. 30 min prior to a single whole body radiation dose of 7 Gy. The experiments were performed using immunohistochemistry for caspase-3, cleaved caspase-3, p53, p-p53 (Ser 15), Puma, p38 and p-p38 (Thr 180/Tyr 182) protein expression. In addition transmission electron microscopy was used for ultrastructural characterization of apoptosis. Data showed that: (i) amifostine significantly reduced the number of apoptotic cells, (ii) p-p53 and Puma proteins were strongly immunostained in granulocytes after irradiation (Ami−/rad+), (iii) amifostine decreased the immunostaining of the proteins (Ami+/rad+), (iv) p38 was immunolocalized in physiological conditions in the nucleus and cytoplasm of granulocytes and neither radiation nor amifostine changed the protein immunostaining or its subcellular distribution, but influenced its activation, (v) radiation-induced p38 phosphorylation and its cytoplasmic accumulation during apoptosis signaling in granulocytes after whole body high radiation dose and amifostine markedly reduced these effects.     

结局指标在缺血性脑卒中病人康复护理路径中的应用研究

[目的]运用护理结局指标构建缺血性脑卒中病人康复护理路径,为护士在临床服务全过程中提供标准化的语言链接和可供度量的尺度,同时培养临床护士发现、思考、解决问题的能力,也为病人在临床就医体验提供规范化、连续性、科学化的护理服务模式。[方法]通过病例回顾性研究和文献研究,由2名研究者独立提取护理记录的相关概念、归类到缺血性脑卒中46项核心护理结局。[结果]最终10项护理结局中有33个结局指标差异具有统计学意义(P<0.01),包括上肢肌力、下肢肌力、爬楼梯的耐受性、以有效的步态行走、慢走、中速行走、走、平衡、协调、步态、表现正常的能力水平、显示完成日常任务的能力、表现出适当的修饰和卫生、括约肌伸缩性、排便时肌肉的伸缩性、排便无须辅助措施、如厕、沐浴、走路、吞咽测试的结果、对食物的容受、吞咽不适、音质变化、正确使用支持器械、采取正确推重物的技巧、表现出肌力良好、充足的液体摄入、排尿模式、意识的尿意、说道感到焦虑、血压升高、说道恐慌感、恐慌感。[结论]以护理结局指标为导向构建的缺血性脑卒中病人康复护理路径,可为病人在临床就医体验提供规范化、连续性、科学化的护理服务模式,提高医护工作的水平。     

维甲酸相关孤核受体α与Wnt信号途径及肿瘤的关系

维甲酸相关孤核受体α(retinoid acid receptor related orphan receptor α,RORα)是核受体超家族中的一员,广泛分布于机体各组织,具有多种重要的生理功能.近年来,RORα与肿瘤的关系受到越来越多的关注,RORα在肿瘤发生中的作用是目前研究的热点之一.研究表明:RORα的表达...     

人组织因子途径抑制因子在毕赤酵母中高拷贝表达

目的 构建高拷贝表达重组人组织因子途径抑制因子的毕赤酵母并对蛋白表达条件进行初步优化,为相关研究奠定基础.方法 将PCR扩增得到的TFPI cDNA片段与表达质粒pPIC9K连接构建重组质粒rhTFPI-pPIC9K,采用PCR方法及DNA测序对其进行鉴定.将重组质粒转化酵母细胞GS115,利用G418抗性实验筛选含有...     

PP-1蛋白稳定高表达MC3T3-E1成骨样细胞系的建立

目的建立稳定高表达蛋白质磷酸酶-1(protein phasphatase-1,PP-1)的MC3T3-E1成骨样细胞系。方法采用RT-PCR技术从MC3T3-E1细胞中扩增蛋白质磷酸酶-1(PP-1)基因,将获得的基因定向插入pCI-neo真核表达质粒中,PCR及双酶切鉴定后用脂质体将表达载体转染入MC3T3-E1细胞,经G418加压有限稀释筛选,建立稳定高表达PP-1的MC3T3-E1成骨样细胞系,采用Western blot法检测PP-1的蛋白表达情况。结果 PCR及双酶切鉴定表明表达载体pCI-neo-PP-1构建正确;Western blot检测结果显示PP-1蛋白能在转染pCI-neo-PP-1的MC3T3-E1细胞中稳定高表达。结论成功建立了稳定高表达PP-1的MC3T3-E1成骨样细胞系,为进一步深入研究PP-1在细胞力学信号转导通路中的功能及作用机制奠定了实验基础。