Objective To establish and compare the pulsed-field gel electrophoresis (PFGE), multiple-locus variable number tandem repeat analysis (MLVA) and automated ribotyping for subtyping of Citrobacter strains. Methods P...Objective To establish and compare the pulsed-field gel electrophoresis (PFGE), multiple-locus variable number tandem repeat analysis (MLVA) and automated ribotyping for subtyping of Citrobacter strains. Methods PFGE protocol was optimized in terms of plug preparation procedure, restriction enzymes and configuration of electrophoretic parameters. MLVA method was evaluated by finding variable number tandem repeats in two genomes of Citrobacter strains. The ribotyping was performed by using the automated RiboPrinter system. Results We optimized the plug preparation procedure, focused on the cell suspension concentration (turbidity of 2.5 to 3.5), SDS addition (no SDS needed) and lysis time (1 h), and selected the appropriate restriction enzyme (Xbal) and the electrophoretic parameters (1.0 s-20.0 s for 19 h) of PFGE. There was nearly no discriminatory power of MLVA between Citrobacter strains. For 51 Citrobacter strains, automated ribotyping gave a D-value of 0.9945, while PFGE gave a D-value of 0.9969. Both PFGE and automated ribotyping clustered strains from the same sources (with the same species from the same place at the same time identified as the same source) and divided strains from different sources (from different years, places and hosts) into different subtypes. Conclusion PFGE protocol established in this paper and automated ribotyping are suitable for application in Citrobacter subtyping.展开更多
AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were per...AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (GP202 and MKN45) and GP202 clones expressing recombinant MUC1 with different VNTR lengths. RESULTS: Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P < 0.05) adhesion to all the cell lines and clones tested, when compared to the non-pathogenic strain HPTx30a. Bacteria showed a significantly higher (P < 0.05) adhesion to the GP202 cell line, when compared to the MKN45 cell line. Furthermore, both strains showed a significantly higher (P < 0.05) adhesion to GP202 clones with larger MUC1 VNTR domains. CONCLUSION: This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells. The extent of bacterial adhesion depends on the size of theMUC1 VNTR domain. The adhesion is further dependent on bacterial pathogenicity and the gastric cell line. MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa.展开更多
Objective:Interleukin-1(IL-1)is a pro-inflammatory cytokine which may be related to urolithiasis.Genetic polymorphisms of the interleukin-1beta(IL-1β)have been proposed as markers for urolithiasis in some areas.Due t...Objective:Interleukin-1(IL-1)is a pro-inflammatory cytokine which may be related to urolithiasis.Genetic polymorphisms of the interleukin-1beta(IL-1β)have been proposed as markers for urolithiasis in some areas.Due to the high incidence of urolithiasis in Uighur children(Xinjiang,China)and existence of ethnic difference,our aim is to explore the potential of IL-1 gene polymorphisms and urolithiasis among these children.Methods:Genomic DNA extracted from peripheral blood of 115 patients and 98 controls were used for genotype polymorphisms analyses.IL-1 receptor antagonist(IL-1RN)gene variable number of tandem repeat(VNTR)gene polymorphisms were analyzed by PCR method.PCR-based restriction analysis was done for the IL-1β(-511)and IL-1β(+3954)gene polymorphisms by endonucleases Ava I and Taq I,respectively.The genotype distribution,allele frequencies,carriage rate,and haplotype frequencies were statistically analyzed.Results:No significant differences were observed in genotypic frequencies between pediatric urolithiasis patients and control group for IL-1RN gene(χ^(2)=1.906,p=0.605),IL-1β(-511)gene(χ^(2)=0.105,p=0.949),or IL-1β(+3954)gene(χ^(2)=3.635,p=0.169).There were yet no significant differences of the allele frequencies of IL-1RN VNTR gene(p=0.779),IL-1β(-511)gene(p=0.941),and IL-1β(+3954)gene(p=0.418)in the case and control groups,as well as the carriage rate and haplotype of them(all p>0.05).Conclusions:The associations between IL-1RN VNTR,IL-1β(-511)and IL-1β(+3954)genes polymorphisms and urolithiasis were not significant in Uighur children.The results need to be confirmed in studies with larger population sample size,as well as in other ethnic groups.展开更多
Background: Medullary cystic kidney disease (MCKD) is clinically indistinguishable from several other autosomal-dominant renal diseases: thus, molecular genetic testing is needed to establish a definitive diagnosi...Background: Medullary cystic kidney disease (MCKD) is clinically indistinguishable from several other autosomal-dominant renal diseases: thus, molecular genetic testing is needed to establish a definitive diagnosis. A specific type of single cytosine insertion in the variable number tandem repeat (VNTR) of the mucin 1 (MUC1) gene is the only known cause of MCKD1; however, genetic analysis of this mutation is difficult and not yet offered routinely. To identify the causative mutation/s and establish a definitive diagnosis in a Chinese family with chronic kidney disease, clinical assessments and genetic analysis were performed, including using a modified genotyping method to identify the MUC1-VNTR single cytosine insertion. Methods: Clinical data from three patients in a Chinese family with chronic kidney disease were collected and evaluated. Linkage analysis was used to map the causative locus. Mutation analysis of uromodulin (UMOD) gene was performed using polymerase chain reaction (PCR) and direct sequencing. For MUC1 genotyping, the mutant repeat units were enriched by Mwol restriction, and then were amplified and introduced into pMD-18T vectors. The 192 clones per transformant were picked up and tested by colony PCR and second round of Mwol digestion. Finally, Sanger sequencing was used to confirm the MUC1 mutation. Results: Clinical findings and laboratory results were consistent with a tubulointerstitial lesion. Linkage analysis indicated that the family was compatible with the MCKDI locus. No mutations were found in UMOD gene. Using the modified MUC1 genotyping method, we detected the MUC1-VNTR single cytosine insertion events in three patients of the family; and mutation-containing clones were 12/192, 14/192, and 5/96, respectively, in the three patients. Conclusions: Clinical and genetic findings could support the MCKDI diagnosis. The modified strategy has been demonstrated to be a practical way to detect MUCI mutation.展开更多
目的:初步了解江苏省结核分枝杆菌临床分离菌株的数目可变串联重复序列(Variable number of tandem repeats,VNTR)的基因型及VNTR基因分布特征。方法:在苏南、苏中、苏北三个地区13个结核病定点诊疗单位收集临床分离菌株。选取结核分枝...目的:初步了解江苏省结核分枝杆菌临床分离菌株的数目可变串联重复序列(Variable number of tandem repeats,VNTR)的基因型及VNTR基因分布特征。方法:在苏南、苏中、苏北三个地区13个结核病定点诊疗单位收集临床分离菌株。选取结核分枝杆菌基因组中11个具有明显多态性特征的VNTR位点,通过PCR扩增,2%琼脂糖凝胶电泳和Bio Numerics(Version 3.0)软件进行结核菌株VNTR的多态性和聚类分析。结果:共收集到168株结核分枝杆菌。不同的菌株在同一位点上具有多态性。共分为10个基因型(Ⅰ,Ⅱ~Ⅹ型),其中以Ⅷ型为主要基因型,占75.0%、其次为Ⅱ型5.4%、Ⅳ型4.2%、Ⅶ型9.5%。不同地区之间,苏南、苏中、苏北三个地区也都以Ⅷ型为主要基因型,分别占各地区的83.5%,57.1%,76.6%;但是苏南、苏中、苏北三地的Ⅱ、Ⅲ、Ⅳ、Ⅶ型菌株分布在各地菌株中的比例有差异显著性((2=54.710,P<0.0001),Ⅱ型以苏中为主(11.9%)、Ⅲ型以苏南为主(3.8%)、Ⅳ型以苏南、苏北为主(5.1%与6.4%)、Ⅶ型以苏中为主(31.0%)。结论:江苏省的结核分枝杆菌具有明显的多态性,以Ⅷ型为主要流行型,不同地区间同样以Ⅷ型为主要流行型,但菌型分布存在一定的差异。展开更多
目的了解辽宁地区炭疽芽胞杆菌的流行特征及菌型基因特征。方法通过多位点可变数目串联重复序列(Multiple locus variable numbers of tandem repeats analysis,MLVA)分型实验,对2001—2011年辽宁省分离到的6株炭疽芽胞杆菌分离株DNA进...目的了解辽宁地区炭疽芽胞杆菌的流行特征及菌型基因特征。方法通过多位点可变数目串联重复序列(Multiple locus variable numbers of tandem repeats analysis,MLVA)分型实验,对2001—2011年辽宁省分离到的6株炭疽芽胞杆菌分离株DNA进行检测,DNA指纹图谱使用BioNumerics 4.0软件进行统计分析,得出聚类分析结果。结果聚类分析发现,6株炭疽芽胞杆菌株可分为2个基因型。对于炭疽暴发而言,其可变数目串联重复序列遗传标记具有高度相似性。结论炭疽芽胞杆菌基因组中的串联重复序列可作为炭疽芽胞杆菌基因分型的指标,在炭疽暴发事件中的病原体溯源上具有重要的意义。展开更多
基金supported by the project (grant 2005CB522904 and 2005CB522905) from the Ministry of Scientific Technologythe project (grant 2008ZX10004-001, 2008ZX10004-008, and 2009ZX10004-101) from the Ministry of Scientific Technology and the Ministry of Health of the People’s Republic of China
文摘Objective To establish and compare the pulsed-field gel electrophoresis (PFGE), multiple-locus variable number tandem repeat analysis (MLVA) and automated ribotyping for subtyping of Citrobacter strains. Methods PFGE protocol was optimized in terms of plug preparation procedure, restriction enzymes and configuration of electrophoretic parameters. MLVA method was evaluated by finding variable number tandem repeats in two genomes of Citrobacter strains. The ribotyping was performed by using the automated RiboPrinter system. Results We optimized the plug preparation procedure, focused on the cell suspension concentration (turbidity of 2.5 to 3.5), SDS addition (no SDS needed) and lysis time (1 h), and selected the appropriate restriction enzyme (Xbal) and the electrophoretic parameters (1.0 s-20.0 s for 19 h) of PFGE. There was nearly no discriminatory power of MLVA between Citrobacter strains. For 51 Citrobacter strains, automated ribotyping gave a D-value of 0.9945, while PFGE gave a D-value of 0.9969. Both PFGE and automated ribotyping clustered strains from the same sources (with the same species from the same place at the same time identified as the same source) and divided strains from different sources (from different years, places and hosts) into different subtypes. Conclusion PFGE protocol established in this paper and automated ribotyping are suitable for application in Citrobacter subtyping.
基金Portuguese Foundation for Science and Technology(FCT)Project POCTI/CBO/44812/2002+1 种基金Project POCTI/SAU-IMI/56895/2004 National Institutes of Health, R01-CA57362
文摘AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (GP202 and MKN45) and GP202 clones expressing recombinant MUC1 with different VNTR lengths. RESULTS: Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P < 0.05) adhesion to all the cell lines and clones tested, when compared to the non-pathogenic strain HPTx30a. Bacteria showed a significantly higher (P < 0.05) adhesion to the GP202 cell line, when compared to the MKN45 cell line. Furthermore, both strains showed a significantly higher (P < 0.05) adhesion to GP202 clones with larger MUC1 VNTR domains. CONCLUSION: This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells. The extent of bacterial adhesion depends on the size of theMUC1 VNTR domain. The adhesion is further dependent on bacterial pathogenicity and the gastric cell line. MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa.
基金This work was supported by the Natural Science Foundation of Guangdong Province,China(No.2019A1515010891).
文摘Objective:Interleukin-1(IL-1)is a pro-inflammatory cytokine which may be related to urolithiasis.Genetic polymorphisms of the interleukin-1beta(IL-1β)have been proposed as markers for urolithiasis in some areas.Due to the high incidence of urolithiasis in Uighur children(Xinjiang,China)and existence of ethnic difference,our aim is to explore the potential of IL-1 gene polymorphisms and urolithiasis among these children.Methods:Genomic DNA extracted from peripheral blood of 115 patients and 98 controls were used for genotype polymorphisms analyses.IL-1 receptor antagonist(IL-1RN)gene variable number of tandem repeat(VNTR)gene polymorphisms were analyzed by PCR method.PCR-based restriction analysis was done for the IL-1β(-511)and IL-1β(+3954)gene polymorphisms by endonucleases Ava I and Taq I,respectively.The genotype distribution,allele frequencies,carriage rate,and haplotype frequencies were statistically analyzed.Results:No significant differences were observed in genotypic frequencies between pediatric urolithiasis patients and control group for IL-1RN gene(χ^(2)=1.906,p=0.605),IL-1β(-511)gene(χ^(2)=0.105,p=0.949),or IL-1β(+3954)gene(χ^(2)=3.635,p=0.169).There were yet no significant differences of the allele frequencies of IL-1RN VNTR gene(p=0.779),IL-1β(-511)gene(p=0.941),and IL-1β(+3954)gene(p=0.418)in the case and control groups,as well as the carriage rate and haplotype of them(all p>0.05).Conclusions:The associations between IL-1RN VNTR,IL-1β(-511)and IL-1β(+3954)genes polymorphisms and urolithiasis were not significant in Uighur children.The results need to be confirmed in studies with larger population sample size,as well as in other ethnic groups.
文摘Background: Medullary cystic kidney disease (MCKD) is clinically indistinguishable from several other autosomal-dominant renal diseases: thus, molecular genetic testing is needed to establish a definitive diagnosis. A specific type of single cytosine insertion in the variable number tandem repeat (VNTR) of the mucin 1 (MUC1) gene is the only known cause of MCKD1; however, genetic analysis of this mutation is difficult and not yet offered routinely. To identify the causative mutation/s and establish a definitive diagnosis in a Chinese family with chronic kidney disease, clinical assessments and genetic analysis were performed, including using a modified genotyping method to identify the MUC1-VNTR single cytosine insertion. Methods: Clinical data from three patients in a Chinese family with chronic kidney disease were collected and evaluated. Linkage analysis was used to map the causative locus. Mutation analysis of uromodulin (UMOD) gene was performed using polymerase chain reaction (PCR) and direct sequencing. For MUC1 genotyping, the mutant repeat units were enriched by Mwol restriction, and then were amplified and introduced into pMD-18T vectors. The 192 clones per transformant were picked up and tested by colony PCR and second round of Mwol digestion. Finally, Sanger sequencing was used to confirm the MUC1 mutation. Results: Clinical findings and laboratory results were consistent with a tubulointerstitial lesion. Linkage analysis indicated that the family was compatible with the MCKDI locus. No mutations were found in UMOD gene. Using the modified MUC1 genotyping method, we detected the MUC1-VNTR single cytosine insertion events in three patients of the family; and mutation-containing clones were 12/192, 14/192, and 5/96, respectively, in the three patients. Conclusions: Clinical and genetic findings could support the MCKDI diagnosis. The modified strategy has been demonstrated to be a practical way to detect MUCI mutation.
文摘目的:初步了解江苏省结核分枝杆菌临床分离菌株的数目可变串联重复序列(Variable number of tandem repeats,VNTR)的基因型及VNTR基因分布特征。方法:在苏南、苏中、苏北三个地区13个结核病定点诊疗单位收集临床分离菌株。选取结核分枝杆菌基因组中11个具有明显多态性特征的VNTR位点,通过PCR扩增,2%琼脂糖凝胶电泳和Bio Numerics(Version 3.0)软件进行结核菌株VNTR的多态性和聚类分析。结果:共收集到168株结核分枝杆菌。不同的菌株在同一位点上具有多态性。共分为10个基因型(Ⅰ,Ⅱ~Ⅹ型),其中以Ⅷ型为主要基因型,占75.0%、其次为Ⅱ型5.4%、Ⅳ型4.2%、Ⅶ型9.5%。不同地区之间,苏南、苏中、苏北三个地区也都以Ⅷ型为主要基因型,分别占各地区的83.5%,57.1%,76.6%;但是苏南、苏中、苏北三地的Ⅱ、Ⅲ、Ⅳ、Ⅶ型菌株分布在各地菌株中的比例有差异显著性((2=54.710,P<0.0001),Ⅱ型以苏中为主(11.9%)、Ⅲ型以苏南为主(3.8%)、Ⅳ型以苏南、苏北为主(5.1%与6.4%)、Ⅶ型以苏中为主(31.0%)。结论:江苏省的结核分枝杆菌具有明显的多态性,以Ⅷ型为主要流行型,不同地区间同样以Ⅷ型为主要流行型,但菌型分布存在一定的差异。
文摘目的了解辽宁地区炭疽芽胞杆菌的流行特征及菌型基因特征。方法通过多位点可变数目串联重复序列(Multiple locus variable numbers of tandem repeats analysis,MLVA)分型实验,对2001—2011年辽宁省分离到的6株炭疽芽胞杆菌分离株DNA进行检测,DNA指纹图谱使用BioNumerics 4.0软件进行统计分析,得出聚类分析结果。结果聚类分析发现,6株炭疽芽胞杆菌株可分为2个基因型。对于炭疽暴发而言,其可变数目串联重复序列遗传标记具有高度相似性。结论炭疽芽胞杆菌基因组中的串联重复序列可作为炭疽芽胞杆菌基因分型的指标,在炭疽暴发事件中的病原体溯源上具有重要的意义。