流行性乙型脑炎病毒结构蛋白编码基因的重组构建

目的:建立流行性乙型脑炎病毒(JEV)C、prME,E等结构蛋白编码基因克隆.方法:病毒感染C6/36细胞,RT-PCR法依次获取该病毒结构蛋白基因并进行DNA测序分析,PCR克隆法将PCR产物分别构建于真核表达载体pcDNA 3.1的BamHI与EcoRI酶切位点并依次命名为pJC、pJME与pJE,通过DNA测序、电泳以及限制性内切酶分析加以鉴定.结果:JEV C、prME与E基因片段分别为380、2001以及1 500bp,各基因测序结果与发表的JEV JaGAr-01株相对应序列相一致,从重组质粒释出的插入子分别与各基因大小相符合.结论:pJC、pJME与pJE重组质粒分别含有C、prME与E蛋白编码基因.     

中国人丙型肝炎病毒囊膜蛋白2HVR1 cDNA的序列分析

目的：了解中国ＨＣＶ流行株高变区１（ＨＶＲ１）的特点。方法：对来自山东（ＳＤ）、上海（ＳＨ）两地患者血清ＲＮＡ进行逆转录－巢式ＰＣＲ，扩增ＨＣＶ囊膜蛋白２基因片段，用ＰＣＲ直接测序法对该片段进行序列测定。结果：（１）扩增片段（命名为Ｐ３８８）对应于日本ＨＣＶ－Ｊ株序列核苷酸１４３９￣１８２６位（氨基酸位３７１￣４９８）；（２）中国人ＨＣＶ ＨＶＲ１位于氨基酸位３８４￣４１０，与发表的ＨＣＶⅡ型ＨＶ     

A concordance of nucleotide substitutions in the first and second hypervariable segments of the human mtDNA control region

A new and easily accessible concordance of nucleotide substitutions in the hypervariable segments of the human mitochondrial DNA (mtDNA) control region has been constructed. The concordance indexes all population-specific mtDNA sequences in a standardized format. The first edition of the concordance includes 1,440 sequences representing 762 mtDNA types from over 65 populations for hypervariable region 1, and 520 sequences representing 260 mtDNA types from over 26 populations for hypervariable region 2. Investigators are invited to submit new sequences to the database, and details for doing so are given in the text.     

Point mutation in the band 4.2 gene associated with autosomal recessively inherited erythrocyte band 4.2 deficiency

Abstract: A patient who represented acute hemolytic crisis was studied. Analysis of the erythrocyte membrane proteins by SDS-PAGE revealed a deficiency of band 4.2. In the family, the sister of the patient who had been clinically normal was also shown to be deficient in band 4.2. Binding studies showed that the propositus' membranes were able to bind normal band 4.2 protein as much as control. It was suggested that the binding sites for the protein were prepared on the membrane. We analyzed the band 4.2 cDNA of the propositus and detected a mutation that changes a codon for alanine to one for threonine at residue 142. Band 4.2 exon III of genomic DNA which included the mutation site was amplified and sequenced directly in the family members, and it was revealed that only the homozygotes of the mutation allele manifested band 4.2 deficiency and the parents, who were heterozygotes, showed normal amounts of band 4.2. Recently, the same mutation was reported as Protein 4.2^NIPPON in another 4 cases (Bouhassira et al. Blood 1992: 79: 1846–1854). This study supports the hypothesis that this mutation is the pathogenetic cause of band 4.2 deficiency and not a polymorphism.     

紫癜性肾炎患儿肠道菌群变化及临床意义研究

背景目前国内外关于过敏性紫癜（HSP）患儿肠道菌群变化的研究数量有限,且尚未见关于紫癜性肾炎（HSPN）患儿疾病早期肠道菌群变化的相关报道。目的 探讨HSPN患儿肠道菌群的变化及其在疾病发生、发展中的作用。方法 于2019年7—9月选取郑州大学第一附属医院儿科收治的37例HSP初治患儿作为试验组,另外同时选取12例健康志愿儿童作为对照组;并对HSPN患儿随访6个月,根据有无肾损伤进一步分为无肾损伤试验亚组13例和肾损伤试验亚组24例。收集HSP患儿与健康儿童的一般资料及粪便标本,应用高通量测序技术对所有研究对象的肠道菌群进行测序及分析,采用Alpha多样性（Shannon指数、Chao1指数、ACE指数）分析探讨样本内的微生物群落的丰度和多样性,通过主坐标分析（PCoA）来探究不同组别间群落结构的差异,利用线性判别分析及影响因子（LEfSe）分析找到组间差异显著的物种。结果 Alpha多样性分析显示,三组研究对象Shannon指数、Chao1指数、ACE指数比较,差异均无统计学意义（P>0.05）。PCoA显示,三组研究对象肠道菌群群落结构均有差异（P<0.05）;Adon...     

种植体黏膜下微生物在健康种植体和种植体周炎中的构成与差异：一项横断面研究

目的：探索种植体黏膜下微生物在健康种植体和种植体周炎中的构成与差异,并分析与临床指标存在相关性的菌种,为种植体周炎的病因学研究提供参考。方法：采用横断面研究,共纳入49例患者,20例为健康种植体,29例为种植体周炎,共采集49份黏膜下微生物样本进行16S核糖体RNA(16S ribosomal RNA, 16S rRNA)基因高通量测序。对两组样本的多样性、菌群构成和差异物种进行分析和比较,采用Spearman相关性分析评价菌种与探诊深度(probing pocket depth, PPD)之间的相关性。结果：健康组的α多样性显著低于种植体周炎组[Chao1指数：236.85±66.13 vs. 150.54±57.43,P<0.001; Shannon指数：3.42±0.48 vs. 3.02±0.65,P=0.032]。主成分分析显示,两组样本的群落结构差异有统计学意义[相似性分析(analysis of similarities, ANOSIM),R²=0.243,P=0.001]。与健康种植体相比,种植体周炎黏膜下菌斑中的牙周致病菌显著增加,包括红色...     

Single-Cell RNA Sequencing of Tumor-Infiltrating NK Cells Reveals that Inhibition of Transcription Factor HIF-1α Unleashes NK Cell Activity

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Changes in gut bacterial communities in canaries infected by Macrorhabdus ornithogaster

Macrorhabdus ornithogaster is an opportunistic yeast that colonizes the gastric mucosa of many avian species. Until now, no studies have focused on the influence of a gastric infection on the balance of the intestinal microbiota of birds. In this study, 44 faecal samples from individual canaries, with and without M. ornithogaster infection, were analysed. The detection of the yeast was evaluated by 18S rRNA PCR. In order to evaluate the impact of the Macrorhabdus infection on the bacterial communities, culture-independent methods, by the use of amplicon-based sequencing as well as 16S rRNA-DGGE, were adopted. The different health status of animals affected the relative abundance of the main OTUs, with a greater diversification of the gut microbiota in healthy animals compared to the infected. In particular, Lactococcus, Pseudomonas, Acinetobacter, Lachnospiraceae, Propionibacterium and Weissella were found to be characteristic of uninfected animals (FDR?<?0.05), while Lactobacillus and Candidatus Arthromitus were characteristic of infected animals (FDR?<?0.05). Both these taxa have been reported as immunostimulatory, involved in immunological disorders. In infected animals the inferred metagenome assessed by PICRUST clearly showed a positive correlation between the presence of M. ornithogaster and KEGG genes related to ether lipid metabolism, already reported to be immunostimulatory by activation of macrophages and to play a pathophysiological role in several immunological disorders. Finally, our results show an interaction between infection of the digestive tract and intestinal microbiota of pet birds and provide insight into the changing of the complex enteric bacterial community.

• HIGHLIGHTS

• Macrorabdus ornithogaster is a gastric yeast that colonizes a wide range of birds.

• Differences were found between infected and healthy animals in gut microbiota.

• Candidatus Arthromitus was closely associated with infected birds.

• M. ornithogaster can affect intestinal microbiota composition of canaries.

     

Expression of human immunodeficiency virus type 1gag gene using genetically engineered herpes simplex virus type 1 recombinants

Infectious herpes simplex virus type 1 (HSV-1) recombinants were constructed by inserting the cDNA sequence of the human immunodeficiency virus type 1 (HIV-1)gag gene (from nucleotide position 675 [SacI] to 3859 [Asp 718] of the cDNA sequences of HIV-1 strain BH-10) within the DNA sequences of theBamHI DNA fragment B of the genome of an apathogenic HSV-1 strain HFEM. This HSV-1 strain possesses a 4.1-kbp deletion within theBamHI DNA fragment B between 0.762 and 0.789 map units of the viral genome, which allows the insertion of at least 4 kbp of foreign genetic material into this particular region. The DNA sequences of the immediate early promoter (IE4) of HSV-1 that were inserted upstream from thegag gene were used as a promoter. The screening of 205 virus stocks derived from individual plaques revealed that 46 recombinant viruses harbor HIV-1gag-specific DNA sequences. However, it was found that only six of the recombinant viruses are able to express thegag gene product of HIV-1. This indicates that the ratio of the positive recombination events is about 2.9%.