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1.
Biomed Environ Sci ; 31(5): 351-362, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29866217

RESUMO

OBJECTIVE: We determined the genetic diversity of Mycobacterium tuberculosis (MTB) in a remote mountainous area of southwest China and evaluated the resolving ability of single nucleotide polymorphism (SNP) genotyping combined with variable number tandem repeat (VNTR) genotyping for Beijing family strains in association with drug resistance status. METHODS: Three hundred thirty-one MTB strains were isolated from patients living in mountainous regions of southwest China, and 8-loci SNP, VNTR-15 genotyping assays, and drug susceptibility testing of 9 drugs were performed. RESULTS: A total of 183 [55.29% (183/331)] strains were classified into the Beijing family. Of the 183 strains, 111 (60.66%) were defined as modern Beijing strains. The most predominant modern Beijing sub-lineage and ancient Beijing sub-lineage were Bmyc10 [39.34% (72/183)] and Bmyc25 [20.77% (38/183)], respectively. Of the isolates, 19.64% (65/331) were resistant to at least 1 of the 9 anti-TB drugs and 17 [4.98% (17/331)] MTB isolates were multi-drug resistant tuberculosis (MDR-TB). Two hundred sixty-one isolates showed a clustering rate of 14.18% (37/261) and a discriminatory index of 0.9990. The Beijing lineage exhibited a significantly higher prevalence of MDR-TB, as well as resistance to isoniazid (INH), rifampin (RIF), and para-aminosalicylic acid (PAS) when analyzed independently (P = 0.005, P = 0.017, P = 0.014, and P = 0.006 respectively). The Beijing lineage was not associated with genetic clustering or resistance to any drug. In addition, genetic clustering was not associated with drug resistance. CONCLUSION: MTB strains demonstrate high genetic diversity in remote mountainous areas of southwest China. Beijing strains, especially modern Beijing strains, are predominant in remote mountainous area of China. The combination of 8-loci SNPs and VNTR-15 genotyping is a useful tool to study the molecular epidemiology of MTB strains in this area.


Assuntos
Farmacorresistência Bacteriana , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleotídeo Único , Tuberculose/epidemiologia , Tuberculose/microbiologia , Antituberculosos/farmacologia , China/epidemiologia , Análise por Conglomerados , Genótipo , Humanos , Filogenia
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 39(6): 992-5, 2008 Nov.
Artigo em Zh | MEDLINE | ID: mdl-19253844

RESUMO

OBJECTIVE: To explore the relationship between renal ADCs (apparent diffusion coefficient values) and renal interstitial fibrosis (RIF) grades. METHODS: Twenty four patients with chronic renal diseases and 48 healthy volunteers (control group) were examined with SS-EPI DWI at 3. OT MR. In chronic renal disease group, RIF of 14 patients who received renal biopsy was determined as grade I and II based on the tubuleinterstitial damage degree, while RIF of 10 patients with uremia, who did not receive biopsy but had nephrogenic renal atrophy, was categorized as grade III. RESULTS: With comparison of the study group and control group, ADCs of renal cortex were significantly different. In either grade II or III RIF, and ADCs of renal medulla showed difference in grade III RIF (P<0.05). Also, ADCs of both cortex and medulla displayed a decreasing trend as RIF grade increased (P<0.05). CONCLUSION: ADCs of renal cortex and medulla may reflect the grades of RIF. ADC of renal cortex might be more sensitive than that of renal medulla.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Córtex Renal/fisiopatologia , Nefrite Intersticial/diagnóstico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Fibrose/diagnóstico , Fibrose/etiologia , Humanos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/complicações , Adulto Jovem
3.
Sci Rep ; 5: 11902, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26154567

RESUMO

We have devised a novel amplification strategy based on isothermal strand-displacement polymerization reaction, which was termed multiple cross displacement amplification (MCDA). The approach employed a set of ten specially designed primers spanning ten distinct regions of target sequence and was preceded at a constant temperature (61-65 °C). At the assay temperature, the double-stranded DNAs were at dynamic reaction environment of primer-template hybrid, thus the high concentration of primers annealed to the template strands without a denaturing step to initiate the synthesis. For the subsequent isothermal amplification step, a series of primer binding and extension events yielded several single-stranded DNAs and single-stranded single stem-loop DNA structures. Then, these DNA products enabled the strand-displacement reaction to enter into the exponential amplification. Three mainstream methods, including colorimetric indicators, agarose gel electrophoresis and real-time turbidity, were selected for monitoring the MCDA reaction. Moreover, the practical application of the MCDA assay was successfully evaluated by detecting the target pathogen nucleic acid in pork samples, which offered advantages on quick results, modest equipment requirements, easiness in operation, and high specificity and sensitivity. Here we expounded the basic MCDA mechanism and also provided details on an alternative (Single-MCDA assay, S-MCDA) to MCDA technique.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Temperatura , Animais , Sequência de Bases , Primers do DNA , Microbiologia de Alimentos , Ordem dos Genes , Loci Gênicos , Listeria monocytogenes/genética , Dados de Sequência Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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