2003～2007年中国风疹病毒基因特征分析

本研究用Vero细胞或Vero/SLAM细胞从我国10个省(直辖市、自治区,下同)2003～2007年风疹暴发和散发病例的咽拭子标本中分离到57株风疹病毒,用RT-PCR方法扩增了57株风疹病毒E1基因1 107个核苷酸的片段,并对该PCR产物进行序列测定和分析.结果提示,在基于WHO基因定型靶序列739个核苷酸片段构建的基因亲缘关系树上,其中55株风疹病毒株属于1E基因型,相对于其他国家的1E基因型,形成一个独立分支;另外2株风疹病毒属于2B基因型.57株风疹病毒大部分核苷酸的突变为无义突变,氨基酸序列高度保守,除了2株风疹病毒在E1蛋白血凝抑制和中和位点区域第212位氨基酸由Thr变为Ser,其他病毒株均无重要抗原位点的改变;所有我国已分离到的1E基因型风疹病毒在E1蛋白第338位氨基酸共享突变位点(Leu338→Phe338),而其他基因型以及其他国家的1E基因型风疹病毒在该位点均未发生突变,提示该氨基酸(Phe338)可能是我国1E基因型风疹病毒所特有.2003～2007年在我国10个省均分离到1E基因型,而2B基因型只在2006年从四川省的越南输入病例中分离到,提示1E为绝对优势基因型,2B基因型为输入基因型.与1979～1984年和1999～2002年我国流行的风疹基因型不同,发生了基因型的更替,近年我国风疹的流行是由1E基因型为主的风疹野病毒的多个传播链引起.     

猪CFL2b基因在成肌细胞中的表达及对肌球蛋白重链基因表达的影响

猪CFL2b基因主要在骨骼肌中表达,对肌肉的发育和肌纤维的形成具有一定作用。为了解猪CFL2b基因与肌纤维性状的相关性,利用定向克隆和基因转染技术获得能稳定表达猪CFL2b基因的成肌细胞株,荧光显微镜观察及Western Blotting检测CFL2b基因在成肌细胞中的表达;应用实时定量PCR技术对细胞内肌球蛋白重链基因（MyHC）的表达变化进行检测。结果显示：CFL2b基因对MyHC的表达有明显影响,其中MyHC2x基因和MyHC26基因的表达明显上调,MyHCl／slow的表达变化不明显。表明CFL2b基因与猪的肌纤维性状密切相关,推测猪CFL2b基因的高表达可能导致猪的不良肉质性状,可以考虑将CFL2b基因作为猪肉质性状的候选基因[动物学报54（6）：1014—1019,2008]。     

Anti-alpha-fodrin antibodies do not add much to the diagnosis of Sjögren's syndrome

The presence of anti-alpha-fodrin autoantibodies has been reported to be a highly specific and sensitive test for the diagnosis of Sj?gren's syndrome (SjS). We looked (in Nijmegen) for anti-alpha-fodrin, anti-Ro60, and anti-La autoantibodies in a cohort of 51 patients with rheumatic diseases (primary SjS [21], secondary SjS 6, rheumatoid arthritis [RA] 12, systemic lupus erythematosus [SLE] 6, and scleroderma 6) and in 28 healthy subjects, using ELISA, immunoblotting, and immunoprecipitation. The same samples were analyzed with an alternative anti-alpha-fodrin ELISA in Hanover. The Nijmegen ELISA of the sera from primary SjS showed sensitivities of 43% and 48% for IgA- and IgG-type anti-alpha-fodrin antibodies, respectively. The Hanover ELISA showed sensitivities of 38% and 10% for IgA- and IgG-type anti-alpha-fodrin antibodies, respectively. The ELISAs for alpha-fodrin showed six (Nijmegen) and four (Hanover) anti-alpha-fodrin-positive RA sera. IgA and IgG anti-fodrin antibodies were also present in four patients with secondary SjS. The sensitivities of Ro60 and La-antibodies in the Nijmegen ELISA were 67% and 62%, respectively. Unlike anti-alpha-fodrin antibodies, all anti-Ro60 and anti-La positive sera could be confirmed by immunoblotting or RNA immunoprecipitation. Thus, anti-Ro and anti-La autoantibodies were more sensitive than anti-alpha-fodrin autoantibodies in ELISA and were more frequently confirmed by other techniques. Anti-La antibodies appear to be more disease-specific than anti-alpha-fodrin antibodies, which are also found in RA sera. Therefore, the measurement of anti-alpha-fodrin autoantibodies does not add much to the diagnosis of Sj?gren's syndrome.     

Melon rugose mosaic virus, the cause of a disease of watermelon and sweet melon

A mechanically transmissible virus with isometric particles c. 32 nm in diameter, was isolated from infected watermelons and sweet melons in the People's Democratic Republic of Yemen. Purified virus preparations contained two major sedimenting components with sedimentation coefficients of 61S and 117S. In isopycn ic centrifugation in CsCl the particles formed a single band of buoyant density 1.39 g cm^-3. Preparations of virus particles comprised of a single polypeptide of mol. wt c. 22 000 and ssRNA of mol. wt 2.1 × 10⁶. The virus was serologically related to three of six subgroups of tymoviruses tested. The name melon rugose mosaic virus is proposed for this newly described virus.     

番茄SlMYB86基因的原核表达及缺氮胁迫下的表达分析北大核心CSCD

MYB转录因子参与植物细胞形态与模式建成、次级代谢的调控以及生物和非生物胁迫应答等反应。该研究采用RT-PCR方法扩增了番茄SlMYB86基因,并进行了聚类分析和保守域序列分析,构建原核表达载体和诱导纯化蛋白,利用qRT-PCR和Western blot检测SlMYB86在缺氮复氮下的表达水平,为深入探究番茄MYB86转录因子在缺氮胁迫下的功能奠定基础。结果表明:(1)番茄SlMYB86与番茄SlMYB26在进化树上属于同一分支,亲缘关系较近,且SlMYB86含有2个Myb_DNA-binding保守结构域,属于R2R3-MYB型转录因子。(2)qRT-PCR分析发现,SlMYB86基因在番茄根和叶中均有表达,缺氮胁迫下SlMYB86表达较对照显著增加。(3)成功构建pET-28a-SlMYB86原核表达载体并转化E.coli BL21(DE3),SDS-PAGE和Western blot结果表明,SlMYB86蛋白的最佳诱导条件为0.5 mmol/L的IPTG、37℃诱导8 h;目的蛋白相对分子量大约为41 kD,与预期大小一致,并获得较高纯度的SlMYB86原核蛋白。(4)将纯化的SlMYB86蛋白免疫小白鼠获得抗体,利用该抗体进行Western blot分析发现,番茄中SlMYB86蛋白在缺氮胁迫后表达上调,表明番茄SlMYB86基因参与了缺氮胁迫的应答。     

应用稳定性同位素技术（δ13C、δ15N）研究长江中游干流主要鱼类的营养级

应用稳定性同位素技术（δ13C、δ15N）对2011年3月至2013年12月采自长江中游干流宜昌、荆州、石首、监利、城陵矶、鄂州、九江和湖口江段的44种鱼类及3种水生无脊椎动物进行了营养级研究。长江中游干流鱼类的δ13C值范围﹣33.83‰（鳙Aristichthys nobilis） ~ ﹣17.36‰（南方鲇Silurus meridionalis）,δ15N值范围4.83‰（泥鳅Misgurnus anguillicaudatus）~ 15.13‰（翘嘴鲌Culter alburnus）。以梨形环棱螺（Bellamya purificata）的δ15N均值5.48‰作为营养级基准线（营养级 = 2）,计算出该江段水生动物的营养级处于2.42 ~ 4.88,主要集中在2.83 ~ 3.61之间,鱼类平均营养级为3.28。营养级大于2.83的鱼类种类数量占了总生物种数的80.85%。大刺鳅（Mastacembelus armatus）和长春鳊（Parabramis pekinensis）营养级最低,分别为2.42 ± 0.49和2.56 ± 0.52,营养层级大于4.0的高级消费者为太湖新银鱼（Neosalanx taihuensis）、短颌鲚（Coilia brachygnathus）、鳙和长蛇鮈（Saurogobio dumerili）,分别为4.88 ± 0.01、4.37 ± 0.27、4.32 ± 0.35和4.09 ± 0.78,小黄黝鱼（Micropercops swinhonis)、鱤（Elopichthys bambusa）、鱖（Siniperca chuatsi）、翘嘴鲌、青鱼（Mylopharyngodon piceus）和南方鲇的营养级分别3.99、3.92 ± 0.16、3.89 ± 0.27、3.87 ± 0.62、3.59 ± 0.69和3.59 ± 0.57。本研究旨为长江中游渔业资源评估及其合理利用提供基础科学资料,为进一步研究长江中游干流渔业资源营养结构的动态变化及受人为活动干扰影响等提供科学参考依据。     

Cofilin蛋白功能及活性调节

Cofilin是普遍存在于真核细胞的一种肌动蛋白结合蛋白. Cofilin的基本功能是在细胞内结合和解聚F肌动蛋白（F-actin）,其活性是通过磷酸化、去磷酸化、磷酸肌醇、pH改变等进行调节.cofilin介导了细胞内的信号途径,从而调节肌动蛋白骨架的重组,对肌肉形态发育起到重要作用.目前,在各种有机体中发现了许多特征性的cofilin蛋白同系物.其中鼠和人有2种cofilin蛋白：cofilin-1（non-muscle cofilin）和cofilin-2（muscle cofilin）.本文根据目前对cofilin的研究结果,从cofilin蛋白结构、功能、活性调节、在肌肉发育中的作用及相关疾病等方面进行阐述.     

Detection of two loci involved in (1-->3)-beta-glucan (curdlan) biosynthesis by Agrobacterium sp. ATCC31749, and comparative sequence analysis of the putative curdlan synthase gene

Genes essential for the production of a linear, bacterial (1-->3)-beta- glucan, curdlan, have been cloned for the first time from Agrobacterium sp. ATCC31749. The genes occurred in two, nonoverlapping, genomic fragments that complemented different sets of curdlan( crd )-deficient transposon-insertion mutations. These were detected as colonies that failed to stain with aniline blue, a (1-->3)-beta-glucan specific dye. One fragment carried a biosynthetic gene cluster (locus I) containing the putative curdlan synthase gene, crdS, and at least two other crd genes. The second fragment may contain only a single crd gene (locus II). Determination of the DNA sequence adjacent to several locus I mutations revealed homology to known sequences only in the cases of crdS mutations. Complete sequencing of the 1623 bp crdS gene revealed highest similarities between the predicted CrdS protein (540 amino acids) and glycosyl transferases with repetitive action patterns. These include bacterial cellulose synthases (and their homologs), which form (1-->4)-beta-glucans. No similarity was detected with putative (1-->3)- beta-glucan synthases from yeasts and filamentous fungi. Whatever the determinants of the linkage specificity of these beta-glucan synthases might be, these results raise the possibility that (1-->3)-beta-glucans and (1-->4)-beta-glucans are formed by related catalytic polypeptides.      

Comparative clinical data for gingivitis treatment using gels from Ocimum sanctum (Tulsi) and chlorhexidine (CHX)

Ocimum sanctum (Tulsi) has various properties like anti bacterial, anti inflammatory, anti oxidant for curing diseases. It is a plant with known medicinal value in Indian system of medicine. Therefore, it is of interest to evaluate the effectiveness of Ocimum sanctum with Chlorhexidine (CHX) which is a standard material for the treatment of gingivitis. We used 30 gingivitis subjects divided into 2 groups. Group I used Tulsi gel (n= 15) and Group II used CHX gel (n = 15) for treatment. Tulsi and CHX gel use was advised for 1 month. The Clinical parameters assessed were gingival Index (GI), plaque Index (PI), probing depth (PD) and clinical attachment loss (CAL) assessed at a time interval of 30 days. Statistical analysis was completed using the SPSS software 23.0. Data showed that GI and PD for Tulsi and CHX in pre and post groups are not significant with p > 0.05. Moreover, PI is not significant with p>0.05 among pre Tulsi, pre CHX and post CHX. However, data is significant with p<0.05 for Tulsi group. CAL is significant with p<0.05 among pre/post Tulsi groups. However, this is not significant with p>0.05 among pre/post CHX groups. Data shows that 2% of Tulsi is effective in reducing gingival bleeding and inflammation. Thus, clinical data shows that Tulsi gel is promising for the treatment of gingivitis.