C '散点图:一种描述氨基酸结构差异的新方法

研究氨基酸结构对蛋白质结构预测具有重要意义.目前主要采用二面角来描述氨基酸的几何结构,但是角度的方法比较抽象,并且难量化地评估结构差异的程度.提出一种描述氨基酸结构差异的新方法——C'散点图.这种方法用散点图的形式在三维坐标图上显示羧基碳原子C'的相对坐标,以描述氨基酸结构的多样性,比目前广泛使用的二面角方法更加直观,在分析多肽片段中氨基酸结构多样性方面具有较高的可视性和便利性.同时通过计算散点图上原子间的最远距离,该方法可望使量化衡量氨基酸结构差异性成为可能.C'散点图对进一步深化氨基酸结构分析具有重要意义.     

DNA-PKcs单链抗体DPK3-scFv的原核表达纯化及生物学作用研究

目的原核表达和纯化DNA依赖性蛋白激酶催化亚单位(DNA-dependent protein kinase catalytic subunit,DNA-PKcs)单链抗体DPK3-scFv,观察其透入细胞及干扰辐射诱发DNA-PKcs磷酸化修饰的生物学作用。方法 PCR扩增DPK3-scFv基因,插入到带有His标签的原核表达载体pET28a,重组质粒转化工程菌BL21、优化表达。免疫荧光显微镜和蛋白免疫印迹观察DPK3-scFv透膜进入HeLa细胞及对电离辐射诱发靶分子DNA-PKcs的磷酸化修饰的影响。结果成功构建单链抗体表达载体pET28a-DPK3-scFv,在2xYT培养基(16 g胰蛋白胨、5 g酵母提取物和10 g NaCl溶于1 L双蒸水中,高压灭菌)、20℃温度、0.2 mmol/L异丙基-β-D-硫代吡喃半乳糖苷(isopropy1-β-D-thiogalactopyranoside,IPTG)条件下诱导可溶性表达,进一步获得了纯化单链抗体。DPK3-scFv能体外抑制DNA-PKcs激酶活性,纯化的DPK3-scFv可跨膜进入细胞内,并与DNA-PKcs共定位在细胞核。DPK3-scFv对γ射线照射HeLa细胞中DNA-PKcs及其S2056位点(pS2056)的自磷酸化具有显著抑制作用。结论通过优化条件获得了可溶性原核表达的DPK3-scFv单链抗体,具有抑制其靶分子DNA-PKcs的磷酸激酶活性。     

趋化因子受体4与肿瘤

趋化因子受体4（CXCR4）属于G蛋白耦联受体超家族,具有趋化免疫细胞、维持免疫细胞的动态平衡等生物学作用。CXCR4表达于多种类型的组织和细胞,在多种肿瘤及肿瘤的不同阶段,CXCR4的表达都明显高于正常组织。CXCR4与肿瘤细胞的增殖、黏附、侵袭和转移有关,在肿瘤的进展中发挥重要作用。     

lncRNA FEZF1-AS1 Is Associated With Prognosis in Lung Adenocarcinoma and Promotes Cell Proliferation,Migration, and Invasion

Long noncoding RNAs (lncRNAs) have been reported to play important roles in tumorigenesis. In the present study, we demonstrated that lncRNA forebrain embryonic zinc finger protein 1 (FEZF1) antisense RNA1 (FEZF1-AS1) is markedly upregulated in human lung adenocarcinoma (LAD) tissues and cell lines and is associated with poor prognosis. Loss of function revealed that deletion of FEZF1-AS1 expression significantly inhibited the LAD cell proliferation, invasion, and migration. Further studies revealed that downregulation of FEZF1-AS1 reduced mRNA and protein expression of its sense-cognate gene FEZF1 in LAD cells, and vice versa. Correlation analysis indicated that there was a positive correlation between FEZF1-AS1 and FEZF1 expression in LAD tissues. Additionally, rescue assay confirmed that the function of FEZF1-AS1 in LAD was mediated by FEZF1. Our findings suggested that dysregulation of FEZF1-AS1 contributed to the progression of LAD, which might be a potential target for LAD therapy.     

山莨菪碱对正常及自发性高血压大鼠离体血管舒张功能的影响

目的:观察山莨菪碱对离体正常(Wistar)大鼠及自发性高血压大鼠(spontaneously hypertensive rats,SHR)腹主动脉舒张作用的影响,并探讨其可能的作用机制。方法:采用大鼠离体腹主动脉环(长度为4~5 mm的血管)灌流技术,观察山莨菪碱对正常大鼠及SHR血管舒张功能的影响,并观察苯肾上腺素(phenylephrine,PE)、左旋硝基精氨酸甲酯(L-NAME)预处理对山莨菪碱作用的影响。结果:山莨菪碱对PE预收缩的正常大鼠内皮完整和去内皮血管的舒张作用差异显著(P<0.05);对PE预收缩的SHR内皮完整及去内皮血管环,山莨菪碱均具有显著舒张作用,呈剂量-效应关系,最大舒张率分别为(78.6±6.9)%和(65.76±11.39)%,无统计学差异。用NOS抑制剂L-NAME预处理正常大鼠内皮完整的血管环,可显著地抑制山莨菪碱诱导的舒张作用(P<0.05)。山莨菪碱对SHR血管的舒张作用能够被L-NAME抑制,抑制前后最大舒张率分别为61%和11.9%(P<0.01)。结论:山莨菪碱可能通过内皮和平滑肌2条途径发挥舒张大鼠离体腹主动脉的作用。     

苯丙酮尿症患者智能障碍程度与基因型相关性分析

目的了解苯丙酮尿症（ｐｈｅｎｙｌｋｅｔｏｎｕｒｉａ，ＰＫＵ）患者智能障碍程度与突变基因性质的关系。方法应用ＰＣＲ－ＡＳＯ及ＰＣＲ－ＳＳＣＰ方法对４５例经典型ＰＫＵ患儿作突变基因检测。对查明基因型的２７例患儿就其智能障碍程度及基因突变性质作一比较。结果苯丙氨酸羟化酶基因型与患儿智能障碍程度缺乏一致性。２７例中仅８例表型与基因型相符，１９例不符。结论苯丙氨酸羟化酶基因突变性质与其表达的酶活性、与治疗前血苯丙氨酸浓度高低相关，但与就诊晚、未经治疗的患儿的智能障碍程度缺乏一致性     

Enlargement of the Anterior Horn of the Lateral Ventricle in Schizophrenic Patients: Chronological and Morphometrical Studies

Abstract: The anterior horn and lateral ventricular sizes of the brain CT were selected for measurement and comparison between 47 schizophrenic patients and 48 neurotic cases, which constituted the control subjects. The ventricular brain ratio (VBR) and the linear ratio (LR 1–6) in multiple age groups were calculated, analyzed and compared using the Student's t test, the two-way ANOVA and Bonferroni's methods. It was found that the VBR of the anterior horn and modified bicaudate cerebroventricular index of the teenage schizophrenics were significantly greater than those of the teenage controls (p < 0.01) and the ventricular sizes were not associated with the different stages of age except for the cases of the teenage group. These results support the hypothesis of previous investigators that the ventricular enlargement is present early in the course of schizophrenia and provide additional evidence that in teenage schizophrenic patients there is a tendency of the enlargement of the anterior horn of the lateral ventricle which may be related with a morphological vulnerability in the prefrontal cortex.     

An Autopsied Case of Acute Lymphocytic Meningoencephalitis with a Long Clinical Course: Special Reference to CT, MR, SPECT and Neuropathological Findings

Abstract: This report describes the clinico-pathological features of acute lymphocytic meningoencephalitis (ALME) of a patient with a long clinical course of 24 months. The patient rapidly developed a confusional state, occasionally with stupor, various involuntary movements and generalized convulsions followed by fever and headache at the age of 29. Clinical symptoms, except fever and convulsions, had not distinctly improved throughout the clinical course, and cortical atrophy on CT and MR gradually progressed. SPECT revealed a low blood perfusion in the cerebral cortices. Neuropathologically, inflammatory findings were very mild, but nerve cells degenerated prominently. From these clinicopathological findings, it is suggested that chronic degenerative changes followed an acute inflammatory phase.