Publications by authors named "Xiaoman Weng"

Leprosy is an infectious disease caused by Mycobacterium leprae (M. leprae), with about 210,000 new cases per year worldwide. Although numerous risk loci have been uncovered by genome-wide association studies, the effects of common genetic variants are relatively modest.

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Leprosy remains persistently endemic in several low- or middle income countries. Transmission is still ongoing as indicated by the unabated rate of leprosy new case detection, illustrating the insufficiency of current prevention methods. Therefore, low-complexity tools suitable for large scale screening efforts to specifically detect M.

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Leprosy continues to be prevalent in some mountainous regions of China, and genotypes of leprosy strains endemic to the country are not known. Mycobacterium lepromatosis is a new species that was discovered in Mexico in 2008, and it remains unclear whether this species exists in China. Here, we conducted PCR- restriction fragment length polymorphism (RFLP) analysis to classify genotypes of 85 DNA samples collected from patients from 18 different provinces.

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Objective: To understand the genotypes of Mycobacterium leprae collected from Guangdong province, China and to analyze the routes of leprosy transmission both inside and outside of Guangdong. The impact of emigrant leprosy patients to the endemic nature of the disease in Guangdong was also studied.

Methods: Typing on strains with variable number of tandem repeats (VNTR) and single nucleotide polymorphism (SNP) were performed on the local cases and emigrant cases based on skin biopsy.

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Leprosy continues to be detected at near stable rates in China even with established control programs, necessitating new knowledge and alternative methods to interrupt transmission. A molecular epidemiology investigation of 190 patients was undertaken to define Mycobacterium leprae strain types and discern genetic relationships and clusters in endemic and non-endemic regions spanning seventeen provinces and two autonomous regions. The findings support multiple locus variable number of tandem repeat (VNTR) analysis as a useful tool in uncovering characteristic patterns across the multiethnic and divergent geographic landscape of China.

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Objective: To explore the factors influencing the steady transmission of leprosy as indicated by new case detection rate in Qiubei county, Yunnan province, China despite the implementation of MDT for the last 25 years.

Methods: Information related to case-finding was collected. ELISA and PCR were applied to detect anti-PGL-1 antibody in sera and Mycobacterium leprae in nasal secretions respectively, in leprosy patients, their household contacts and the general population.

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Leprosy continues to be endemic in parts of China. To track the occurrence of leprosy and determine at risk communities, molecular strain typing based on variable number of tandem repeats (VNTRs) was applied in Qiubei County, Wenshan Prefecture, Yunnan Province of the People's Republic of China, a multiethnic region that is home to four predominant ethnic minorities. A previous study, conducted between 2002 and 2005, provided the first descriptions of Mycobacterium leprae strains in the region.

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Objective: To evaluate the reliability and feasibility of two methods of multilocus variable number of tandem repeat analysis (MLVA) for strain typing of M. leprae, and to study whether short tandem repeat loci are stable and suitable for epidemiological study of leprosy.

Methods: Total DNA was extracted from skin biopsies of 20 new multibacillary (MB) patients from China diagnosed in 2006.

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Objective: Multiple locus variable number-tandem repeat (VNTR) analysis (MLVA) had been proposed as a means of strain typing for tracking of source and studying the transmission chain of pathogens. However, empirical data for a defined population from scale and duration were lacking for studying the transmission chain of leprosy.

Methods: MLVA on 7 VNTR loci was applied to the strain typing on prevalent Mycobacterium leprae isolates collected from Qiubei county, Yunnan province during 2002-2006 in the study on the relationship between geographic distribution and genotypes of M.

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Article Synopsis
  • A study was conducted in Qiubei County, China, focusing on the diversity and distribution of Mycobacterium leprae strains, since the region has a leprosy detection rate significantly higher than the national average.
  • The research involved 68 newly diagnosed leprosy patients and utilized multiple-locus variable-number tandem-repeat (MLVA) analysis on DNA from skin biopsies, revealing a range of alleles which allowed for distinct strain identification.
  • The findings indicated that many patients belonged to multicase families with similar VNTR profiles, suggesting that there is localized transmission of leprosy, possibly linked to social interactions in village markets.
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Objective: To understand the genotypic mapping of Mycobacterium leprae identified in China and to compare with those from other countries to select suitable alleles for epidemiological investigation in the transmission chain of leprosy.

Methods: Various number of tandem repeat(VNTR) in genomic DNA of Mycobacterium leprae was used in the present genotyping study. 33 skin biopsies from Wenshan prefecture,Yunnan province and 17 from other parts of China were studied.

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