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C Bebear - One of the best experts on this subject based on the ideXlab platform.

  • development of multiple locus variable number tandem repeat analysis for Molecular Typing of mycoplasma pneumoniae
    Journal of Clinical Microbiology, 2009
    Co-Authors: S Degrange, Charles Cazanave, A Charron, H Renaudin, C Bebear
    Abstract:

    In this study we report on the development of a multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) method for the Molecular Typing of Mycoplasma pneumoniae. The genomic content of M. pneumoniae M129 was analyzed for VNTRs, and 5 of the 17 VNTRs identified were selected for use in an MLVA assay. The method was based on a GeneScan analysis of VNTR loci labeled with fluorescent dyes by multiplex PCR and capillary electrophoresis. This approach was applied to a collection of 265 isolates from various European countries, Japan, and Tunisia; and 26 distinct VNTR types were found. The VNTR assay was compared to the P1 adhesin PCR-restriction fragment length polymorphism (RFLP) Typing method and showed a far better resolution than the P1 PCR-RFLP method. The discriminatory power of MLVA (Hunter-Gaston diversity index [HGDI], 0.915) for the 265 isolates was significantly higher than that of the P1 PCR-RFLP method (HGDI, 0.511). However, there was a correlation between the Typing results obtained by MLVA and the P1 gene PCR-RFLP method. The potential value of MLVA of M. pneumoniae as an epidemiological tool is discussed, and the use of the VNTR markers in further investigations of the potential use of MLVA in outbreaks of M. pneumoniae infections is proposed.

Seonghan Kim - One of the best experts on this subject based on the ideXlab platform.

Herminia De Lencastre - One of the best experts on this subject based on the ideXlab platform.

  • comparison of dna sequencing of the protein a gene polymorphic region with other Molecular Typing techniques for Typing two epidemiologically diverse collections of methicillin resistant staphylococcus aureus
    Journal of Clinical Microbiology, 2001
    Co-Authors: Duarte C Oliveira, Ines Crisostomo, Ilda Santossanches, Peter Major, Rute C Alves, Marta Airesdesousa, Marianne Konkoly Thege, Herminia De Lencastre
    Abstract:

    The aim of this study was to compare the recently developed Typing approach for methicillin-resistant Staphylococcus aureus (MRSA) based on the DNA sequencing of the protein A gene polymorphic region (spaA Typing) with a combination of three well-established Molecular Typing techniques: ClaI-mecA vicinity polymorphisms, ClaI-Tn554 insertion patterns, and SmaI pulsed-field gel electrophoresis (PFGE) profiles. In order to evaluate the applicability of this Typing technique in different types of studies, two groups of MRSA clinical isolates were analyzed: a collection of 185 MRSA isolates circulating in Hungary recovered from 17 hospitals in seven cities during a 3-year period (1994 through 1996), and a selection of 53 MRSA strains isolated in a single hospital in Hungary between 1997 and 1998. The 238 MRSA clinical strains from Hungary were first classified in clonal types (defined as ClaI-mecA::ClaI-Tn554::SmaI-PFGE patterns), and 65 of the 238 strains, representing major MRSA clones and some sporadic clones, were further analyzed by spaA Typing. Our results showed that the lineages most recently introduced in the hospital setting showed little variability in spaA types, whereas the MRSA clones circulating for a longer period of time and spread among several hospitals showed a higher degree of variability. The implementation of the spaA Typing method was straightforward, and the results obtained were reproducible, unambiguous, and easily interpreted. This method seems to be adequate for outbreak investigations but should be complemented with other techniques in long-term surveillance or in studies comparing distant clonal lineages.

Mathieu Picardeau - One of the best experts on this subject based on the ideXlab platform.

  • application of multilocus variable number tandem repeat analysis for Molecular Typing of the agent of leptospirosis
    Journal of Clinical Microbiology, 2006
    Co-Authors: Laurence Salaun, Fabrice Merien, Svetlana Gurianova, Guy Baranton, Mathieu Picardeau
    Abstract:

    Leptospirosis is a worldwide-distributed zoonosis, endemic in tropical areas. Epidemiologic investigations of leptospirosis still rely on tedious serological identification tests. Recently, Molecular Typing systems based on variable-number tandem-repeat (VNTR) analysis have been described and have been used to identify Leptospira interrogans strains. Although L. interrogans is the most common Leptospira species encountered in human infections around the world, other pathogenic species, such as Leptospira kirschneri and Leptospira borgpetersenii, are also frequently associated with human leptospirosis. In this study, we aimed to extend multilocus VNTR analysis (MLVA) identification of strains to species other than L. interrogans. We designed primers for VNTR loci found in L. interrogans, L. kirschneri, and L. borgpetersenii. The discriminatory power of the redefined primers was evaluated on collection strains and then on clinical strains. We also carried out a retrospective study on 156 strains isolated from patients and animals from New Caledonia, an area of high endemicity in the South Pacific. Our results show that this simple PCR-based MLVA Typing technique is a powerful methodology for the epidemiology of leptospirosis.

Xiang Sheng Che - One of the best experts on this subject based on the ideXlab platform.

  • Molecular Typing of treponema pallidum causing early syphilis in china a cross sectional study
    Sexually Transmitted Diseases, 2012
    Co-Authors: Rui Rui Peng, Wanhui Wei, Hongchu Wang, Angyong Zhu, Quanzhong Liu, Heping Zheng, Shujie Huang, Jinping Zhang, Xiang Sheng Che
    Abstract:

    BACKGROUND There have been limited data on Molecular epidemiology of syphilis in China. This study aimed to analyze strain type distribution of Treponema pallidum causing early syphilis across geographic areas in China using an enhanced method. METHODS Genital samples were collected from patients in East, South, and North China. Positive DNA of T. pallidum was analyzed by arp, tpr, and tp0548 genes. RESULTS Sufficient DNA for full Molecular Typing existed in 197 of 324 samples, and 27 strain types were identified. A range of 3 to 20 repeats (except 4, 11, and 19 repeats) and 25 repeats were found for the 60-bp tandem repeats of the arp gene. This was the first time the 9 and 25 repeats were detected. For the RFLP analysis of the tpr genes, patterns a, d, h, j, and l were identified. This was the first time the h, j, and l patterns were observed in China. For the sequence analysis of the tp0548 gene, sequences c, e, and f were identified. Strain type distribution was significantly different across geographic areas (χ² = 20.6, P = 0.006). Overall, 14d/f was most predominant (39% of fully typed samples, 95% CI = 32%-46%); 13d/f, 15d/f, and 16d/f were next most common (each 13% of fully typed samples, 95% CI = 9%-18%). CONCLUSIONS There is substantial genetic diversity of T. pallidum in China. The broad and ununiform distribution of strain types may reflect differences in regional sexual network patterns. Predominance of few strain types may indicate a linked transmission.

  • Molecular Typing of treponema pallidum a systematic review and meta analysis
    PLOS Neglected Tropical Diseases, 2011
    Co-Authors: Rui Rui Peng, Alberta L Wang, Joseph D Tucke, Xiang Sheng Che
    Abstract:

    Background Syphilis is resurgent in many regions of the world. Molecular Typing is a robust tool for investigating strain diversity and epidemiology. This study aimed to review original research on Molecular Typing of Treponema pallidum (T. pallidum) with three objectives: (1) to determine specimen types most suitable for Molecular Typing; (2) to determine T. pallidum subtype distribution across geographic areas; and (3) to summarize available information on subtypes associated with neurosyphilis and macrolide resistance. Methodology/Principal Findings Two researchers independently searched five databases from 1998 through 2010, assessed for eligibility and study quality, and extracted data. Search terms included “Treponema pallidum,” or “syphilis,” combined with the subject headings “Molecular,” “subTyping,” “Typing,” “genotype,” and “epidemiology.” Sixteen eligible studies were included. Publication bias was not statistically significant by the Begg rank correlation test. Medians, inter-quartile ranges, and 95% confidence intervals were determined for DNA extraction and full Typing efficiency. A random-effects model was used to perform subgroup analyses to reduce obvious between-study heterogeneity. Primary and secondary lesions and ear lobe blood specimens had an average higher yield of T. pallidum DNA (83.0% vs. 28.2%, χ2 = 247.6, p<0.001) and an average higher efficiency of full Molecular Typing (80.9% vs. 43.1%, χ2 = 102.3, p<0.001) compared to plasma, whole blood, and cerebrospinal fluid. A pooled analysis of subtype distribution based on country location showed that 14d was the most common subtype, and subtype distribution varied across geographic areas. Subtype data associated with macrolide resistance and neurosyphilis were limited. Conclusions/Significance Primary lesion was a better specimen for obtaining T. pallidum DNA than blood. There was wide geographic variation in T. pallidum subtypes. More research is needed on the relationship between clinical presentation and subtype, and further validation of ear lobe blood for obtaining T. pallidum DNA would be useful for future Molecular studies of syphilis.