Nucleolar localization of non-structural protein 3b, a protein specifically encoded by the severe acute respiratory syndrome coronavirus

The open reading frame 3 (ORF3) of the severe acute respiratory syndrome coronavirus (SARS-CoV) genome encodes a predicted 154-amino acid protein, which lacks similarities to any known protein, and is named 3b. In this study, it was shown that 3b protein was predominately localized to nucleus with EGFP tag at its N- or C-terminus. The localization patterns were similar in different transfected cells. Immuno-fluorescence assay revealed that 3b protein was co-localized well with C23 in nucleolus. C23, B23 and fibrillarin all are important nucleolar proteins, which localize in the region of the nucleolus. Co-transfection of p3b-EGFP with pC23-DsRed, pB23-DsRed and pfibrillarin-DsRed further confirmed 3b's nucleolus localization. With construction of serial truncated mutants of 3b, a region (residues 134-154 aa) responsible for nucleolar localization was determinated in 3b protein. These results provide a new insight for further functional studies of SARS-CoV 3b protein.     

结缔组织生长因子在血吸虫病肝纤维化鼠肝窦内皮细胞中的表达及意义

目的:动态观察结缔组织生长因子(CTGF)蛋白在血吸虫病肝纤维化鼠肝窦内皮细胞表达水平的时相变化,探讨其与肝窦内皮细胞下基底膜形成的关系。方法:采用腹部敷贴法建立血吸虫病肝纤维化模型,HE、Masson染色和透射电镜观察其病理变化;免疫组化技术检测CTGF、Ⅳ型胶原(ColⅣ)和层粘连蛋白(LN)在小鼠肝脏组织中的表达和分布;并应用彩色图像分析仪进行定量分析。结果:与正常对照组比较,模型组鼠肝窦内皮细胞表达CTGF蛋白阳性或强阳性,肝窦壁LN、ColⅣ表达水平增高,且随着肝纤维化的发展,CTGF和LN、ColⅣ表达逐渐增强,肝窦内皮下基底膜逐渐增厚。图像定量分析两组平均吸光度值、平均灰度值和阳性面积比具有统计学差异;CTGF蛋白与LN、ColⅣ水平呈正相关。结论:血吸虫病肝纤维化时小鼠肝窦内皮细胞通过CTGF蛋白表达上调,调控细胞外基质产生,导致ColⅣ、LN分泌增加,参与肝窦内皮下基底膜形成,从而引起肝内微循环障碍。     

人源化抗人肺癌单域抗体基因的构建、表达及活性分析

目的： 构建人源化的抗人肺癌单域抗体hu3D3VH基因, 在大肠杆菌中表达, 对其蛋白活性进行分析.方法： 采用CDR移植技术对mAb3D3的重链可变区进行人源化, 通过重叠PCR获得hu3D3VH的基因.构建pET22（b＋）/hu3D3VH表达载体, 并转化大肠杆菌BL21（DE3）, 在IPTG诱导下表达.表达产物通过Ni亲和层析柱纯化.采用间接ELISA和竞争抑制ELISA法进行活性分析.结果： 通过重叠PCR获得序列正确的目的基因.目的蛋白以包涵体的形式表达, 表达量占菌体总蛋白的30%以上.纯化后, 目的蛋白的纯度达95%以上.hu3D3VH具有与亲本抗体相同的抗原反应性, 并能抑制mAb3D3与L342细胞的结合.结论： 获得的人源化单域抗体hu3D3VH, 保留了与mAb3D3相同的反应性和特异性, 为进一步临床应用奠定了基础.     

肱骨髁上骨折合并肱动脉损伤的诊治

目的：为探讨肱骨髁上骨折合并不同类型肱动脉损伤的诊断与治疗。方法：采用交区克氏针固定骨折，应用机械扩张、血管探查、修补、吻合等措施修复肱动脉。结果：16例于术中探查肱动脉，有断裂伤、刺破伤及顽固性痉挛，均采用手术治疗，使前臂血运得到恢复，骨折得到固定。本组除1例因伤后24小时入院出现前臂缺血性肌挛维、1例因严重粉碎性骨折术后肘关节活动中度受限外，14例均恢复良好，结论：肱骨髁上骨折台井脏动脉损伤的后果严重，但通过及时诊断和有效手术治疗、预后良好。     

周围神经干自然分束部位血管形态及临床意义

应用微血管灌注透明法观察研究5具成人周围神经干标本.重点观察神经自然分束部位微血管形态和分支分布规律.神经干内有非常完兽的血供系统.手术中循神经自然分束进行追踪分离,不会对神经血供产生明显影响.但在张力下牵拉缝合神经,将对神经干血供产生严重影响.神经束膜缝合比神经外膜缝合更强调在无张力下进行.     

Brain Parenchymal and Microvascular Amyloid in Alzheimer's Disease

Brains of patients with Alzheimer disease/senile dementia of Alzheimer type (AD/SDAT) develop a progressive accumulation of amyloid, which deposits primarily in the form of characteristic parenchyma!'plaques' (senile or neuritic plaques/SP's) and as mural deposits in the walls of capillaries and arterioles (cerebral amyloid angiopa-thy/CAA). A major component of this amyloid is a small and unique peptide composed of 39–43 amino acids, beta/A4, which is cleaved from a much larger precursor protein (APP) that has several isoforms. Brain amyloid can be detected in autopsy or biopsy brain tissue by classical, immunohistochemical and ultrastructural (including immuno-electron microscopic) methods of varying sensitivity and specificity. Beta/A4 amyloid deposition is remarkably variable (e.g. predominantly parenchyma! or vascular, or a mixture of parenchymal and vascular) among patients with AD/SDAT. Despite its abundance in the brains of AD/SDAT patients, the precise role of beta/A4 in the pathogenesis of the neurological deficit, neocortical atrophy and progressive synapse loss associated with AD/SDAT has yet to be determined. However, mutations in the gene that encodes APP are clearly associated with familial AD syndromes in which there is significant brain amyloid deposition. CAA, in addition to its association with AD/SDAT, can result in hemorrhagic and (possibly) ischemic forms of stroke. Work with recently developed transgenic mice which express large amounts of beta/A4 in the central nervous system is likely to elucidate mechanisms by which the protein is selectively deposited in the brain in a parenchymal or microvascular form, and how it contributes to the pathogenesis of neurodegeneration.     

强光干扰下的眩光评价研究

眩光是影响视觉的一个重要因素，而眩光后人眼的恢复时间则是进行眩光评价的重要标准。目前的眩光研究都是停留在针对普通照度的眩光源的研究背景下。通过对能产生高照度的眩光源照射后的人眼视觉恢复情况的实验研究，得到在强光干扰条件下的眩光影响因素关系。根据实验数据进行人眼恢复时间计算公式的修正，提出一种在强光干扰下对眩光的客观评价方法。通过实验，基本验证了该公式在高照度情况下的有效性和客观性。     

重型肝炎/肝衰竭临床分类的进一步探讨

目的提高对重型肝炎，肝衰竭临床分类的进一步认识。方法回顾分析25l例急性、亚急性肝衰竭患者的临床资料，按照病因分为无肝病基础组（第l组）、肝炎组（第2组）、肝硬化组（第3组）共3组，并对每组中急性、亚急性肝衰竭的实验室检查、肝性脑病的发病率及预后进行统计学分析。结果（1）转氨酶、胆碱脂酶及白蛋白的差异：无论是急性还是亚急性肝衰竭中，无肝病基础组转氨酶、胆碱脂酶及白蛋白均明显高于有肝病基础患者，特别是高于肝硬化组患者（P〈0．05）；（2）肝性脑病的发病率及各等级分布：在l、2、3组中，急性肝衰竭肝性脑病的发病率分别为100．00％，66．23％和51．02％；亚急性肝衰竭分别为71．42％，54．81％和49．99％；（3）在预后方面：在1、2、3组中急性肝衰竭的好转治愈率分别为15．38％、42．85％和26．09％；亚急性肝衰竭患者33．33％、51．39％和36．85％，3组具有统计学差异（P〈0．05）。结论无论是急性还是亚急性发病，3组重型肝炎，肝衰竭患者的临床特点及其预后均有差异，依此进行分类，有其临床实用性及科学性，将能更好的指导临床诊断、治疗和预后判断。     

红细胞变形性的影响因素及测量方法

红细胞的变形能力是一种重要的流变现象，是影响血液循环的主要因素，具有重要的生理学意义。红细胞的变形能力是某些疾病的重要特征。本文从内部因素、外部因素和其他因素三个方面，介绍了小同因素对红细胞变形性的影响，并比较、讨论了测量红细胞变形性的主要方法。     

Dizygotic twinning is not associated with methylenetetrahydrofolate reductase haplotypes

BACKGROUND: Folate metabolism is critical to embryonic development, influencing neural tube defects (NTD) and recurrent early pregnancy loss. Polymorphisms in 5,10-methylenetetrahydrofolate reductase (MTHFR) have been associated with dizygotic (DZ) twinning through pregnancy loss. METHODS: The C677T and A1298C polymorphisms in MTHFR were genotyped in 258 Australasian families (1016 individuals) and 118 Dutch families (462 individuals) of mothers of DZ twins and a population sample of 462 adolescent twin families (1861 individuals). Haplotypes were constructed from the alleles, and transmission of the MTHFR haplotypes to mothers of DZ twins and from parents to twins in the adolescent twin families analysed. RESULTS: The C677T and A1298C were common in all three populations (frequencies > 0.29). There was strong linkage disequilibrium (D' = 1) between the variants, showing that specific combinations of alleles (haplotypes) were transmitted together. Three haplotypes accounted for nearly all the variation. There was no evidence of any association between MTHFR genotype and twinning in mothers of twins, or of the loss of specific MTHFR genotypes during twin pregnancies. CONCLUSIONS: It is concluded that variation in twinning frequency is not associated with MTHFR genotype.