多肽:N-乙酰氨基半乳糖转移酶基因家族低密度表达谱芯片建立

目的初步创建多肽:N-乙酰氨基半乳糖转移酶基因家族低密度基因芯片,并对人两种肿瘤细胞中的N-乙酰氨基半乳糖转移酶进行表达谱分析.方法主要为PCR和分子杂交技术.结果制成N-乙酰氨基半乳糖转移酶基因家族低密度表达谱基因芯片,通过此芯片采用化学发光法能够检测到人肿瘤细胞中的N-乙酰氨基半乳糖转移酶基因家族不同程度的阳性信号.结论在不同肿瘤细胞中,N-乙酰氨基半乳糖转移酶基因家族表达谱有差异,但它们之间具体的联系还需进一步的研究.     

关于N-乙酰氨基半乳糖转移酶基因家族cDNA扩增的初步研究

目的通过实验方法扩增N-乙酰氨基半乳糖转移酶基因家族cDNA.方法主要通过PCR技术,用各种N-乙酰氨基半乳糖转移酶基因家族cDNA的特异性引物进行扩增并结合电泳技术,用不同的限制性内切酶进行酶切鉴定.结果通过电泳图谱和酶切图谱初步证实了这一家族的不同成员均已得到有效的扩增.结论成功扩增了N-乙酰氨基半乳糖转移酶基因家族cDNA,并为其文库的建立打下良好的基础.     

全反式维甲酸对HL60细胞株三种糖基转移酶家族表达的影响

目的从mRNA水平检测HL60细胞株中多肽:N-乙酰氨基半乳糖转移酶家族(polypeptide:Nacetylgalactosaminytra -nsferases,ppGalNAcTs)、N-乙酰氨基葡萄糖基转移酶家族(UDP-N-acetylglucosamine:beta-galactose betal, 3-N-acetylglucosaminyltransferases,β3GnTs)及O-连接乙酰氨基葡萄糖转移酶家族(O-linked GlcNAc transferase,OGnT)的表达情况,研究全反式维甲酸(All-transretinoic acid,ATRA)培养对不同糖基转移酶表达水平的影响。方法采用Real time RT- PCR方法从mRNA水平上研究ppGalNAcTs、β3GnTs、OGnT的表达以及加入ATRA后表达水平的变化,用3H掺入试验检测加入ATRA对细胞增殖的影响,流式细胞仪观察细胞周期情况,激光共聚焦显微镜观察细胞形态的变化。结果加入ATRA 后HL60细胞株中β3GnT1、ppGalNAcT2表达量急剧增加,细胞阻滞在G2／M期,细胞的生长增殖受到抑制,细胞向粒系分化。结论加入分化诱导剂后细胞发生显著变化,提示β3GnT1、ppGalNAcT2与白血病细胞株的分化可能有一定关系。     

多肽:N-乙酰氨基半乳糖转移酶2(Polypeptide:N-Acetylgalactosaminyltransferases,pp-GalNAc-T2, E.C.2.4.1.41)的mRNA表达谱研究

多肽N-乙酰氨基半乳糖转移酶2是O-糖链合成第一步的糖基转移酶,而O-糖基化与血管内皮细胞的功能密切相关.随着近年来人类基因组计划的迅速发展,人们对糖基转移酶的功能也开始有了新的认识.本文采用RT-PCR法观察了六种不同组织中PP-GalNAC-T2的表达水平,发现PP-GalNAc-T2在胃肠道粘膜等呈高表达,在脑组织中也有一定的表达,提示它在不同组织中的分布与组织功能存在相关性,值得进一步研究.     

多肽：N—乙酰氨基半乳糖转移酶2（Polypeptide：N—Acetylgalactosaminyltransterases，pp—GalNAc—T2,E.C.2.4.1.41）的mRNA表达谱研究

多肽：N—乙酰氨基半乳糖转移酶2是O-糖链合成第一步的糖基转移酶，而O糖基化与血管内皮细胞的功能密切相关。随着近年来人类基因组计划的迅速发展，人们对糖基转移酶的功能也开始有了新的认识。本文采用RT—PCR法观察了六种不同组织中PP—GalNAC—T2的表达水平，发现PP—GalNAc—T2在胃肠道粘膜等呈高表达，在脑组织中也有——定的表达，提示它在不同组织中的分布与组织功能存在相关性，值得进一步研究。     

壳寡糖及其衍生物对实验性糖尿病大鼠抗氧化能力及肾功能的影响

背景：壳寡糖和N-乙酰氨基单糖是高分子不溶性壳聚糖经水解的产物,具有水溶性。由于分子结构相似,壳寡糖和N-乙酰氨基单糖壳聚糖同样具有抗氧化等功效,同时由于其小分子可溶性和易被人体吸收的特性,在糖尿病及其并发症预防与治疗方面有更广阔的应用前景。目的：观察不同剂量的壳寡糖,N-乙酰氨基单糖对链脲佐菌素诱导的糖尿病大鼠抗氧化能力的影响及对肾脏的保护作用。设计、时间及地点：随机对照动物实验,于2008-07/09在中国海洋大学生物化学实验室完成。材料：壳寡糖,N-乙酰氨基单糖由中国海洋大学生物化学实验室制备。81只Wistar大鼠随机分为9组：正常对照组,阴性对照组,二甲双胍组,壳寡糖和N-乙酰氨基单糖低、中、高剂量组,每组9只。方法：正常对照组腹腔内注射柠檬酸缓冲液,其余各组按65mg/kg体质量一次性腹腔内注射链脲佐菌素溶液制备糖尿病大鼠模型。壳寡糖和N-乙酰氨基单糖低、中、高剂量组分别按每日250,500,1500mg/kg灌胃壳寡糖和N-乙酰氨基单糖水溶液,正常对照组,阴性对照组按体质量灌胃等体积凉白开水（10mL/kg）,二甲双胍组按每日200mg/kg灌胃二甲双胍水溶液,连续60d。主要观察指标：①测定血清中谷胱甘肽过氧化物酶、超氧化物歧化酶、丙二醛浓度、总抗氧化能力和肾功能指标。②肾脏病理组织学检查。结果：壳寡糖,N-乙酰氨基单糖可以增加糖尿病大鼠血清中总抗氧化能力及超氧化物歧化酶浓度,显著降低血清中丙二醛、尿素氮、N-乙酰氨基葡萄糖苷酶及尿液中总蛋白/肌酐、N-乙酰氨基葡萄糖苷酶/肌酐的水平。其中以壳寡糖中剂量组（500mg/kg）和N-乙酰氨基单糖低剂量组（250mg/kg）作用效果较好。结论：适量壳寡糖及N-乙酰氨基单糖能够有效的降低链脲佐菌素诱导的糖尿病大鼠的抗氧化能力,从而对肾脏起到了保护作用。     

疾病所致ABO血型变异及改造研究进展

ABH血型抗原是在红细胞、内皮细胞、上皮细胞表面的糖蛋白或糖脂类蛋白上发现的碳水化合物结构。血型物质的前体H受糖基转移酶的修饰和控制。糖基转移酶是由ABO基因的1对等位基因决定，而红细胞上的H抗原则由FuT1基因控制的岩藻糖基转移酶所决定。A抗原由N-乙酰半乳糖胺修饰H抗原表达；     

伴IgA沉积的微小病变肾病综合征患者血清IgA1糖基化缺陷的检测

目的 通过对伴IgA沉积的微小病变肾病综合征（MCNS-IgA）患者血清中IgA1分子糖基化缺陷程度的检测,探讨MCNS-IgA的可能的病理分类归属. 方法 选择北京大学人民医院肾内科MCNS-IgA患者10例,微小病变肾病综合症（MCNS）患者10例、大量蛋白尿IgAN （H-IgAN）患者10例为对照.用双抗体夹心ELISA法检测各组患者血清IgA1的相对浓度,用黑木凝集素检测IgA1分子的α2,6唾液酸水平,花生凝集素检测IgA1分子的半乳糖水平,蜗牛凝集素检测IgA1分子的N-乙酰氨基半乳糖水平,计算经血清IgA1浓度校正的各糖基水平.观察MCNS-IgA组患者血清IgA1分子糖基化缺陷情况,并且与H-IgAN及MCNS组进行比较.结果 与MCNS组相比,MCNS-IgA肾病患者血清IgA1的α2,6唾液酸（1.232±0.250比较1.379±0.623,P=0.455）、半乳糖缺失（0.204±0.053 vs 0.229±0.088,P=0.454）水平及N-乙酰氨基半乳糖暴露（0.191±0.039 vs0.205±0.068,P=0.626）水半无明显差异.但其血清IgA1分子α2,6唾液酸缺失（1.232±0.250vs 0.756±0.243,P=0.015）及N-乙酰氨基半乳糖的暴露（0.191±0.039比0.258±0.066,P=0.025）显著低于H-IgAN组,半乳糖缺失少,但未达统计学差异（0.204±0.053比0.139±0.038,P=0.052）. 结论 MCNS-IgA组患者血清IgA1糖基化水平上显示了与IgA肾病不同的特点,提示其可能是微小病变伴IgA分子的非特异性沉积.     

RUNX3基因与恶性肿瘤关系的研究现状

RUNT转录因子家族是一系列进化相对保守的后生动物蛋白。RUNT家族中的转录因子的氨基末端（N-）都有一个高度相似的RUNT结构域（runt domain,RD）,由128个氨基酸组成,起着与DNA结合和形成异二聚体化的重要作用。     

多肽：N-乙酰氨基半乳糖转移酶-2与共刺激分子B7-H3相互作用的结构信息学初步探讨

目的 研究多肽：N-乙酰氨基半乳糖转移酶-2（ppGalNAc-T2）与共刺激分子B7-H3的相互关系.方法 通过同源模拟,得到共刺激分子B7-H3两种不同剪接体（2IgB7-H3,4IgB7-H3）的分子结构,寻找PDB数据库中的ppGalNAc-T2的蛋白质晶体结构,利用软件GRAMM（http：//vakser.bioinformatics.ku.edu/main/resources_gramm.php）,与同源模拟得到的两种不同剪接体的B7-H3分子结构相结合,寻找两者之间是否存在直接结合的可能.结果 成功地模拟了共刺激分子B7-H3两种剪接体的分子结构,发现ppGalNA-T2与共刺激分子B7-H3有相互结合的可能性.结论 结构生物信息学的研究发现ppGalNAc-T2分子与B7-H3具有潜在相互作用位点,ppGalNAc-T2可能参与B7-H3蛋白质的O-糖链合成反应,并且很有可能是通过直接接触来催化控制B7-H3分子的O-糖链合成.     

Structure-based phylogeny of the metallo-beta-lactamases

The metallo-beta-lactamases fall into two groups: Ambler class B subgroups B1 and B2 and Ambler class B subgroup B3. The two groups are so distantly related that there is no detectable sequence homology between members of the two different groups, but homology is clearly detectable at the protein structure level. The multiple structure alignment program MAPS has been used to align the structures of eight metallo-beta-lactamases and five structurally homologous proteins from the metallo-beta-lactamase superfamily, and that alignment has been used to construct a phylogenetic tree of the metallo-beta-lactamases. The presence of genes from Eubacteria, Archaebacteria, and Eukaryota on that tree is consistent with a very ancient origin of the metallo-beta-lactamase family.     

HCV感染者第一高变区及部分膜区序列变异的分子进化分析

目的比较分析HCV第一高变区及包含第一高变区(HVR1)在内的部分膜区序列变异,从分子进化角度探讨献血者体内HCV变异。方法通过RT-PCR钓取5名HCV感染献血者体内含HVR1的部分膜区序列,选取10个克隆进行序列测定,并采用ClustalX软件,对获得的50条HVR1区和50条膜区序列进行了横断面的分子进化树分析。结果部分HCV感染者体内自身10条HVR1序列之间的亲缘关系较远;但感染者体内10条膜区序列之间亲缘关系较近,并呈现出一定的个体特异性。结论相比单纯分析HVR1区的变异情况,以含HVR1的膜区序列进行的进化分析更能体现出个体的差异,对于HCV的溯源更有意义。     

Informal care as relationship: the case of the Magnificent Seven

Continual and/or repetitive informal caring and the part childhood, developmental and socially constructed identity play roles in adult informal care, form the background to the questions of why individuals gravitate toward such relationships and why they often continue to care in the face of overwhelming obstacles. A synthesis of the literature is presented, leading to personal histories as a method of discovery. The Biographic Narrative Interpretive Method's minimalist interview technique is put forth as the key data-gathering event. Reflecting teams, underpinned by hermeneutics or interpretive phenomenology, are used for the analyses. Data from in-depth, biographic interviews with two informal carers (a mother and her adult son) from a seven-member, three-generational family are presented. The study reveals that this family defines disability as a status that they share in common: disability demonstrates relationships and keeps the family together, but discourages mobility. It is suggested that often-unmet childhood needs propelled these particular individuals into demonstrating those needs as adults by assuming informal care relationships. The case is made that their biographies impact upon their management of health and enduring illnesses within caring roles. Further biographic research within the caring profession is recommended.     

Gambol and Tc1 are two distinct families of DD34E transposons: analysis of the Anopheles gambiae genome expands the diversity of the IS630-Tc1-mariner superfamily

Tc1 is a family of DNA transposons found in diverse organisms including vertebrates, invertebrates and fungi. Tc1 belongs to the IS630-Tc1-mariner superfamily, which is characterized by common 'TA' target site and conserved D(Asp)DE(Glu) or DDD catalytic triad. All functional Tc1-like transposons contain a transposase with a DD34E catalytic triad. We conducted a systematic analysis of DD34E transposons in the African malaria mosquito, Anopheles gambiae, using a reiterative and exhaustive search program. In addition to previously described Tc1-like elements, we uncovered 26 new DD34E transposons including a novel family that we named gambol. Designation of family status to gambol is based on phylogenetic analyses of transposase sequences that showed gambol and Tc1 transposons as distinct clades that were separated by mariner and other families of the IS630-Tc1-mariner superfamily. The distinction between Tc1 and gambol is also consistent with the unique TIRs in gambol elements and the presence of a 'W[I/L/V]DEDC' signature near their N-termini. This signature is predicted as part of the 'RED' domain, a component of the 'PAI' and 'RED' DNA binding domains in Tc1 and possibly mariner. Although gambol appears to be related to a few DD34E transposons from cyanobacteria and fungi, no gambol has been reported in any other insects or animals thus far. Several gambol and Tc1 elements have intact ORFs and different genomic copies with high sequence identity, which suggests that they may have been recently active.     

Cloning and expression analysis of takeout/JHBP family genes of silkworm, Bombyx mori

A Bombyx EST cDNA database was searched using the Drosophila takeout gene and nine cDNAs were obtained. The homology search suggested that these genes are widespread in insects and organize a large gene family, and that they have hydrophobic ligands. A phylogenetic tree indicated that the genes are first divided into two large groups, juvenile hormone binding protein and other protein genes, and the latter group diversified within a short time at an early stage. The expression study of five Bombyx genes indicated that they are expressed in various tissues and are regulated by development and feeding conditions. The Bombyx genes might have roles related to the regulation of metabolism, growth or development related to nutritional conditions.     

Identification and characterization of the cysteine protease inhibitor gene MdCPI from Musca domestica

Cysteine proteinase inhibitors (CPIs) are involved in many vital cellular processes such as signalling pathways, apoptosis, immune response and development; however, no CPIs have yet been reported from the housefly Musca domestica. Here we report the isolation and characterization of a housefly CPI gene designated MdCPI. The gene contains an open reading frame of 357 bp encoding a protein of 118 amino acid residues with a putative signal peptide of 17 amino acid residues. Protein alignment demonstrated a high homology to that of Sarcophaga crassipalpis (identity = 51%). Phylogenetic analysis suggested that all CPIs from dipterans, including the housefly, belong to the I25A family and may be descended from a single common ancestor. The gene was expressed in and purified from Escherichia coli. Biochemical studies showed that MdCPI exerts an inhibiting function on papain, which is a classical assay to confirm CPIs. Real-time quantitative PCR and immunolocalization analysis revealed that MdCPI is specifically expressed in haemocytes and fat bodies. It is highly down-regulated in larvae and markedly up-regulated in the pupal stage, suggesting that it may be related to development.     

Full or near full length nucleotide sequences of TT virus variants (Types SANBAN and YONBAN) and the TT virus-like mini virus

TT virus (TTV) is a common virus and consists of many genotypes and variants. In addition, there exists a virus which both differs greatly from and retains a considerable resemblance to TTV, such as the TTV-like mini virus (TLMV) as we reported previously. Here we report the near full length genomic sequences of 4 isolates of a new variant of TTV (designated YONBAN) along with the full length sequences of 2 isolates of the TTV-SANBAN lineage and 7 isolates of the TLMV species derived from human sera. The TTV-YONBAN sequences showed only about 50% identity at the nucleotide level to those of the prototype TTV (TA278) and to SANBAN, and even less to TLMV. Moreover, the ORF1 of YONBAN lacked the ATG initiation codon which is shared by all the TTV and TLMV isolates so far identified in humans; instead, YONBAN had a Kozak's rule-compatible ACG codon as the candidate initiation site for the ORF1 translation. Nevertheless, the overall genetic structure and the conserved amino acid motifs within the ORF1 and the ORF2 were well shared among the prototype TTV strains, the SANBAN and YONBAN variants, and TLMV. The most conserved nucleotide sequence was found in the noncoding region just upstream from the ORF2, allowing construction of a phylogenetic tree which implied that the TTV genotypes and variants, the TLMV, and chicken anemia virus could be coclassified under a superfamily for which we proposed the name of 'Paracircoviridae' in our previous report.     

利用MICA穿膜区微卫星多态性估算广东汉族和/或中外不同人群间遗传距离

目的调查中国广东汉族人群MICA(MHC classⅠchain related gene A)基因座穿膜区(TM)微卫星多态性分布,并利用MICA-TM微卫星多态性估算广东汉族和/成中外其他人群间遗传距离。方法利用聚合酶链反应对中国广东地区106份无亲缘关系汉族样本作MICA-TM微卫星基因分型,并计算基因频率;使用DISPAN软件计算群体遗传距离并绘制系统树。结果共检出MICA-TM微卫星5个等位基因,即A4、A5、A5.1、A6和A9,其中A5频率最高(0.2877),A4最低(0.1321);初步估算得出广东汉族的遗传距离与山东汉族、成都汉族和云南汉族较近,通过绘制系统树大致勾画出中国汉族人群由西向东迁徙后逐渐向南、北两大区域分叉,形成汉族南北2大群体的遗传特征,广东汉族为南方汉族群体的1支。结论MICA-TM微卫星位点具有较高的遗传多态性,不同人群的分布存在明显差异,适合作为人类遗传标记分析人类迁徙过程,对人类进化研究具有应用价值。     

Phylogeny and species identification of the family Enterobacteriaceae based on dnaJ sequences

Phylogenetic relations within the family Enterobacteriaceae were analyzed using partial dnaJ sequences of 165 strains belonging to 93 species from 27 enterobacterial genera. The dnaJ phylogeny was in relative agreement with that constructed by 16S rDNA sequences, but more monophyletic groups were obtained from the dnaJ tree than from the 16S rDNA tree. The degree of divergence of the dnaJ gene was approximately 6 times greater than that of 16S rDNA. Also, the dnaJ gene showed the most discriminatory power in comparison with tuf and atpD genes, facilitating clear differentiation of any 2 enterobacterial species by dnaJ sequence analysis. The application of dnaJ sequences to the identification was confirmed by assigning 72 clinical isolates to the correct enterobacterial species. Our data indicate that analysis of the dnaJ gene sequences can be used as a powerful marker for phylogenetic study and identification at the species level of the family Enterobacteriaceae.