Rearrangement of the human heavy chain variable region gene V3-23 in transgenic mice generates antibodies reactive with a range of antigens on the basis of VHCDR3 and residues intrinsic to the heavy chain variable region

To formulate a 'logic' for how a single immunoglobulin variable region gene generates antibodies with different antigen specificity and polyreactivity, we analysed chimeric antibodies produced in transgenic mice carrying the germ-line human V3-23 gene, multiple diversity (D) and joining (J) gene segments. Hybridomas producing antibodies encoded by the V3-23 gene in combination with different mouse Vkappa genes were obtained by fusion of splenocytes from transgenic mice. All antibodies had human mu-chains and mouse light chains, were multimeric in structure and expressed the human V3-23 gene. Nucleotide sequence analyses of genes encoding the heavy and light chains of 12 antibodies in relation to antigen specificity highlighted the importance of heavy chain variable region CDR3 in determining reactivity with different antigens. However, the results also suggest that non-CDR3 sequences intrinsic to the V3-23 gene itself may be involved in, or determine, the binding of the chimeric antibodies to some of the antigens tested in the current study.     

Carbapenem-resistant and OXA-23-producing Acinetobacter baumannii isolates in the United Arab Emirates

Five carbapenem-resistant Acinetobacter baumannii isolates, collected from the United Arab Emirates in 2006, were investigated to identify the mechanism(s) responsible for carbapenem resistance. Genotyping was performed by pulsed-field gel electrophoresis, and the location of the bla _OXA-23 gene was determined by using the endonuclease I Ceu I technique and mating-out assays. The four isolates in which the bla _OXA-23 gene was located on the chromosome within a Tn 2006 composite transposon were clonally related. The single non-clonally related isolate harboured the bla _OXA-23 gene on a 70-kb transferable plasmid. This study reports on the dissemination of OXA-23-producing A. baumannii isolates in the Middle East.     

Forensic characteristics and phylogenetic analysis of 23 Y-STR loci in the Miao population from Guizhou province,southwest China

Background: Investigation of haplotype/allele frequency data of Y-STR loci in ethnically diverse populations is essential for forensic reference database construction and genetic application. However, the population genetic characteristics of the Chinese Miao minority from Guizhou Province remain uncharacterised.

Aim: To assess forensic characteristics for 23 Y-Chromosomal STR loci in Guizhou Miao and explore population genetic relationships with geographically neighbouring populations.

Subjects and methods: Twenty-three Y-Chromosomal STRs were genotyped using the Powerplex^® Y23 system in 103 unrelated Chinese Miao males from Guizhou Province, southwest China. Haplotypes and forensic parameters were obtained. Population relationships of Guizhou Miao with others were revealed using AMOVA and an MDS plot.

Results: A total of 96 haplotypes were identified with overall haplotype diversity (HD) and discrimination capacity (DC) of 0.9985 and 0.9320, respectively. Genetic differentiation was observed with most of the comparison populations, prominently for Guizhou Shui.

Conclusion: The 23 Y-STR loci were highly polymorphic and discriminating in the Guizhou Miao population and could be used for forensic practice and population genetic studies. Population relationship analysis revealed Guizhou Miao had a close genetic relationship with geographically close Guizhou Gelao, as well as Han majorities derived from different regions.     

探针ASPCR检测肺炎支原体 微量耐药突变A2063G方法的建立

[摘要]　目的　 建立能够特异性检测微量肺炎支原体（Mycoplasma pneumoniae, MP）A2063G耐药突变基因的特异性扩增等位基因的探针法实时定量PCR（probe-based allele-specific real-time PCR, 探针ASPCR）方法。方法?建立特异性检测A2063G耐药突变位点的探针ASPCR方法,并验证其灵敏度、特异度及准确度等性能。结果?特异性扩增2063G和非特异性扩增2063A/G的引物/探针组合分别扩增105拷贝野生基因型（2063A）模板的Ct值的差(△Ct)高达10.93,能够特异性检测A2063G突变。探针ASPCR方法检测2063G基因型占总MP的比例的准确度可低至1％;检测MP的灵敏度低至10拷贝,检测A2063G耐药突变比例的灵敏度低至0.01％。探针ASPCR方法与前期建立的染料ASPCR方法检测临床样本的MP感染结果一致,MP阳性检出率均为94.83%（55/58）,高于传统巣式PCR联合测序方法的检测结果（75.86%,44/58）;探针ASPCR和染料ASPCR 2种方法检测MP耐药率分别为63.64%（35/55）、70.91%（39/55）,高于传统巣式PCR联合测序方法检测结果59.09%（26/44）。结论?新建探针ASPCR方法是一种具有高特异度、准确度和灵敏度的快速检测MP微量A2063G耐药突变的方法;与染料ASPCR方法相比,探针ASPCR方法检测耐药MP的灵敏度略低,但其临床样本检测复查率也低于染料ASPCR方法,且其结果判读简单,更适合在临床中应用推广,能够为临床制定MP及耐药MP感染的治疗方案提供理论依据。     

Regional Differences in the Prevalence of Anaemia and Associated Risk Factors among Infants Aged 0–23 Months in China: China Nutrition and Health Surveillance

Infantile anaemia has been a severe public health problem in China for decades. However, it is unclear whether there are regional differences in the prevalence of anaemia. In this study, we used data from the China Nutrition and Health Surveillance (CNHS) to assess the prevalence of anaemia and the risk factors associated with its prevalence in different regions. We included 9596 infants aged 0–23 months from the CNHS 2013 database. An infant was diagnosed with anaemia if he/she had a haemoglobin concentration of <110 g/L. We used multivariate logistic regression to investigate the potential risk factors associated with the development of anaemia. We found that anaemia was present in 2126 (22.15%) of the infants assessed. Approximately 95% of these cases were classified as mild anaemia. Based on the guidelines laid out by the World Health Organization, 5.5% and 43.6% of the surveillance sites were categorized as having severe and moderate epidemic levels of anaemia, respectively. The prevalence of infantile anaemia in Eastern, Central and Western China was 16.67%, 22.25% and 27.44%, respectively. Premature birth, low birth weight, breastfeeding and residence in Western China were significantly associated with higher odds of developing anaemia. Female sex and having mothers with high levels of education and maternal birth age >25 years were associated with lower odds of developing anaemia. In conclusion, we observed significant regional disparities in the prevalence of infantile anaemia in China. Western China had the highest prevalence of infantile anaemia, and rural regions showed a higher prevalence of anaemia than urban regions.     

Potential Role of Probiotics in Ameliorating Psoriasis by Modulating Gut Microbiota in Imiquimod-Induced Psoriasis-Like Mice

Psoriasis is an immune-mediated systemic disease that may be treated with probiotics. In this study, probiotic strains that could or could not decrease interleukin (IL)-17 levels were applied to imiquimod (IMQ)-induced psoriasis-like mice via oral administration. Bifidobacterium adolescentis CCFM667, B. breve CCFM1078, Lacticaseibacillus paracasei CCFM1074, and Limosilactobacillus reuteri CCFM1132 ameliorated psoriasis-like pathological characteristics and suppressed the release of IL-23/T helper cell 17 (Th17) axis-related inflammatory cytokines, whereas B. animalis CCFM1148, L. paracasei CCFM1147, and L. reuteri CCFM1040 neither alleviated the pathological characteristics nor reduced the levels of inflammatory cytokines. All effective strains increased the contents of short-chain fatty acids, which were negatively correlated with the levels of inflammatory cytokines. By performing 16S rRNA gene sequencing, the diversity of gut microbiota in psoriasis-like mice was found to decrease, but all effective strains made some specific changes to the composition of gut microbiota compared to the ineffective strains. Furthermore, except for B. breve CCFM1078, all other effective strains decreased the abundance of the family Rikenellaceae, which was positively correlated with psoriasis-like pathological characteristics and was negatively correlated with propionate levels. These findings demonstrated effects of strain-specificity, and how probiotics ameliorated psoriasis and provide new possibilities for the treatment of psoriasis.     

原发性肺鳞癌nm23基因mRNA表达的研究

目的探讨nm23基因表达在原发性肺鳞癌中的作用。方法采用nm23基因寡核酸探针,通过Northern印迹转移的方法,检测17例原发性肺鳞癌患者手术切除的癌组织,癌旁组织和远离癌灶的非癌肺组织中nm23基因mRNA表达水平,并分析nm23mRNA表达水平与肺癌生物特性的相关性。结果肺鳞组织nm23基因mRNA表达水平增高(8.17±3.41)与癌旁组织(4.05±1.90)及远离癌灶的非癌肺组织(3.21±1.97)比较差异有显著性(P<0.05)。有淋巴结转移者nm23基因mRNA表达水平(10.54±3.60)与无淋巴结转移者(5.72±2.51)差异有显著性(P<0.01);癌细胞低分化者(9.83±3.27)与中高分化者(5.96±2.63)差异亦有显著性(P<0.02)。结论肺鳞癌nm23基因mRNA表达水平增高,且与癌的淋巴转移和组织分化有关,但未显示nm23基因mRNA表达在肺鳞癌中的癌转移抑制作用。     

乳腺癌CD44和nm23基因表达与侵袭转移的关系

目的：探讨粘附分子CD44和抑癌基因nm23与乳腺癌侵袭转移的关系。方法：采用逆转录聚合酶链反应（RT－PCR）方法对30例乳腺癌及10例乳腺良性肿瘤组织中CD44V6和nm23-H1基因的表达进行检测,结果：乳腺癌组织中CD44V6及nm23-H1的表达明显高于乳腺良性肿瘤;CD44V6和nm23-H1的阳性表达与乳腺癌的临床分期和是否有淋巴结转移密切相关,而与乳腺癌的病理类型无关。结论：CD44V6和nm23-H1异常表达是乳腺癌发生发展,浸润转移的重要分子学改变。同时检测两者可更好地预测其进展程度和对淋巴结转移的判断。     

膀胱癌P21、P53、nm23蛋白表达的临床意义

目的探讨癌基因与抑癌基因表达与膀胱癌生物学行为的关系.方法应用免疫组化方法对48例膀胱移行细胞癌中P21、P53、nm23蛋白进行检测.结果P21、P53、nm23蛋白表达的阳性率分别是58.3%、47.9%、41.7%.P21、P53蛋白表达阳性率与肿瘤分级、分期及复发呈正相关.nm23蛋白表达阳性率与分级呈正相关,与分期及复发呈负相关.77.1%膀胱癌有上述蛋白异常表达,其中47.9%膀胱癌同时有两个或两个以上蛋白表达.结论癌基因及抑癌基因的异常表达及协同作用,在膀胱癌发生、发展中起重要作用.     

胃癌组织中nm23蛋白表达与微血管密度及其转移的关系研究

目的探讨胃癌组织中nm23蛋白的表达与癌组织微血管密度与转移的关系.方法用免疫组织化学LSAB方法检测85例胃癌癌组织微血管(MVD)及mn23蛋白的表达;在第Ⅶ因子相关抗原(FⅦRAg)染色切片上检测其微血管密度.结果nm23表达阳性淋巴结转移率明显低于nm23表达阴性组,而且差异有显著性.nm23表达阳性组与阴性组比较,nm23表达与MVD呈负相关.结论nm23基因受抑制时,MVD增加,淋巴结转移率增高.因此时nm23及MVD的检测,可作为预测胃癌转移及判断预后的可靠指标之一.