Browsing by Author "Mathukorn Na Ubol"

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    Genome fingerprinting by pulsed-field gel electrophoresis of isolates of Burkholderia pseudomallei from patients with melioidosis in Thailand
    (2000-02-05) Surapong Koonpaew; Mathukorn Na Ubol; Stitaya Sirisinha; Nicholas J. White; Sansanee C. Chaiyaroj; Mahidol University; Chulabhorn Research Institute; Nuffield Department of Clinical Medicine
    A total of 95 isolates of Burkholderia pseudomallei from 53 sporadic cases in Thailand were examined by pulsed-field gel electrophoresis. Digestion of genomic DNA of all isolates by NcoI generated a macrorestriction pattern similar to that of B. pseudomallei which cannot assimilate l- arabinose. Analysis using restriction enzymes SpeI and AvrII demonstrated greater sensitivity than NcoI digestion in the differentiation of B. pseudomallei and could be used for epidemiological groupings. Four cluster groups were evident among 37 isolates tested and the majority of isolates within each cluster displayed more than 65% similarity. Furthermore, multiple isolates from 18 and 35 patients with single and recurrent episodes of melioidosis, respectively, were examined. All patients with a single episode yielded genetically identical isolates and four of 35 patients with recurrent episodes were infected with strains of different genotypic patterns from the primary isolate(s). Hence, most repeated episodes of infection in melioidosis are as a result of the original infecting strains. (C) 2000 Elsevier Science B.V.
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    Sequence and apoptotic activity of VacA cytotoxin cloned from a helicobacter pylori thai clinical isolate
    (2014-01-01) Muhammad Junaid; Sarbast Al-Gubare; Muhammad Yousef; Mathukorn Na Ubol; Somphob Leetachewa; Chatchai Muanprasat; Chanan Angsuthanasombat; Wanpen Chaicumpa; Niaz Ali; Gerd Katzenmeier; University of Malakand; Mahidol University; Khyber Medical University
    The vacuolating cytotoxin VacA produced by Helicobacter pylori induces the formation of large cytoplasmic vacuoles in host gastric epithelial cells as well as a release of cytochrome C from mitochondria resulting in cell apoptosis. Considerable sequence diversity in VacA relating to different degrees of disease severity is observed with clinical samples from a multitude of geographic places. In this study we describe expression in Escherichia coli, purification to homogeneity and in vitro assay of its apoptotic activity of a VacA toxin from a H. pylori isolate of a Thai patient with gastrointestinal lymphoma. Sequencing revealed that the deduced amino acid sequence of the cloned Thai isolate VacA is similar to H. pylori s1/m2 type strains. The percent sequence similarity to the model strain 60190 was lower due to the presence of extra amino acids in the mid (m) region. The purified VacA toxin exhibited significant apoptotic activity on both T84 and MDCK epithelial cell lines, as revealed by DAPI staining, whereby the observed activity was significantly higher on MDCK cells. These findings could relate to a modulation of VacA activity on host cells in the Thai isolate-VacA toxin that may differ from those of the model strain. © 2014 Muhammad Junaid et al.
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    Sequence and apoptotic activity of VacA cytotoxin cloned from a Helicobacter pylori Thai clinical isolate
    (2014) Muhammad Junaid; Al-Gubare, Sarbast; Muhammad Yousef; Mathukorn Na Ubol; Somphob Leetachewa; Chatchai Muanprasat; Chanan Angsuthanasombat; Wanpen Chaicumpa; Niaz Ali; Gerd Katzenmeier; Mahidol University. Institute of Molecular Biosciences; Mahidol University. Faculty of Science. Department of Physiology; Mahidol University. Siriraj Hospital. Faculty of Medicine. Department of Parasitology
    The vacuolating cytotoxin VacA produced by Helicobacter pylori induces the formation of large cytoplasmic vacuoles in host gastric epithelial cells as well as a release of cytochrome C from mitochondria resulting in cell apoptosis. Considerable sequence diversity in VacA relating to different degrees of disease severity is observed with clinical samples from a multitude of geographic places. In this study we describe expression in Escherichia coli, purification to homogeneity and in vitro assay of its apoptotic activity of a VacA toxin from a H. pylori isolate of a Thai patient with gastrointestinal lymphoma. Sequencing revealed that the deduced amino acid sequence of the cloned Thai isolate VacA is similar to H. pylori s1/m2 type strains. The percent sequence similarity to the model strain 60190 was lower due to the presence of extra amino acids in the mid (m) region. The purified VacA toxin exhibited significant apoptotic activity on both T84 and MDCK epithelial cell lines, as revealed by DAPI staining, whereby the observed activity was significantly higher on MDCK cells. These findings could relate to a modulation of VacA activity on host cells in the Thai isolate-VacA toxin that may differ from those of the model strain.