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Mitchell A Yakrus - One of the best experts on this subject based on the ideXlab platform.
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comparison of methods based on different molecular epidemiological markers for typing of mycobacterium tuberculosis complex strains interlaboratory study of discriminatory power and reproducibility
Journal of Clinical Microbiology, 1999Co-Authors: Kristi Kreme, D Van Soolinge, Richard Frothingham, Walte H Haas, P W M Hermans, Carlos Marti, Prasi Palittapongarnpim, Onnie Plikaytis, Lee W Riley, Mitchell A YakrusAbstract:In this study, the currently known typing methods for Mycobacterium tuberculosis isolates were evaluated with regard to reproducibility, discrimination, and specificity. Therefore, 90 M. tuberculosis complex strains, originating from 38 countries, were tested in five restriction fragment length polymorphism (RFLP) typing methods and in seven PCR-based assays. In all methods, one or more repetitive DNA elements were targeted. The strain typing and the DNA fingerprint analysis were performed in the laboratory most experienced in the respective method. To examine intralaboratory reproducibility, blinded duplicate samples were included. The specificities of the various methods were tested by inclusion of 10 non-M. tuberculosis complex strains. All five RFLP typing methods were highly reproducible. The reliability of the PCR-based methods was highest for the mixed-linker PCR, followed by variable numbers of tandem repeat (VNTR) typing and spoligotyping. In contrast, the double repetitive element PCR (DRE-PCR), IS6110 inverse PCR, IS6110 ampliprinting, and arbitrarily primed PCR (APPCR) typing were found to be poorly reproducible. The 90 strains were best discriminated by IS6110 RFLP typing, yielding 84 different banding patterns, followed by mixed-linker PCR (81 patterns), APPCR (71 patterns), RFLP using the polymorphic GC-Rich Sequence as a probe (70 patterns), DRE-PCR (63 patterns), spoligotyping (61 patterns), and VNTR typing (56 patterns). We conclude that for epidemiological investigations, strain differentiation by IS6110 RFLP or mixed-linker PCR are the methods of choice. A strong association was found between the results of different genetic markers, indicating a clonal population structure of M. tuberculosis strains. Several separate genotype families within the M. tuberculosis complex could be recognized on the basis of the genetic markers used.
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comparison of methods based on different molecular epidemiological markers for typing of mycobacterium tuberculosis complex strains interlaboratory study of discriminatory power and reproducibility
Journal of Clinical Microbiology, 1999Co-Authors: Kristin Kremer, Richard Frothingham, Walte H Haas, P W M Hermans, Prasi Palittapongarnpim, Lee W Riley, D Van Soolingen, Carlos Martin, B B Plikaytis, Mitchell A YakrusAbstract:In this study, the currently known typing methods for Mycobacterium tuberculosis isolates were evaluated with regard to reproducibility, discrimination, and specificity. Therefore, 90 M. tuberculosis complex strains, originating from 38 countries, were tested in five restriction fragment length polymorphism (RFLP) typing methods and in seven PCR-based assays. In all methods, one or more repetitive DNA elements were targeted. The strain typing and the DNA fingerprint analysis were performed in the laboratory most experienced in the respective method. To examine intralaboratory reproducibility, blinded duplicate samples were included. The specificities of the various methods were tested by inclusion of 10 non-M. tuberculosis complex strains. All five RFLP typing methods were highly reproducible. The reliability of the PCR-based methods was highest for the mixed-linker PCR, followed by variable numbers of tandem repeat (VNTR) typing and spoligotyping. In contrast, the double repetitive element PCR (DRE-PCR), IS6110 inverse PCR, IS6110 ampliprinting, and arbitrarily primed PCR (APPCR) typing were found to be poorly reproducible. The 90 strains were best discriminated by IS6110 RFLP typing, yielding 84 different banding patterns, followed by mixed-linker PCR (81 patterns), APPCR (71 patterns), RFLP using the polymorphic GC-Rich Sequence as a probe (70 patterns), DRE-PCR (63 patterns), spoligotyping (61 patterns), and VNTR typing (56 patterns). We conclude that for epidemiological investigations, strain differentiation by IS6110 RFLP or mixed-linker PCR are the methods of choice. A strong association was found between the results of different genetic markers, indicating a clonal population structure of M. tuberculosis strains. Several separate genotype families within the M. tuberculosis complex could be recognized on the basis of the genetic markers used.
D. Van Soolingen - One of the best experts on this subject based on the ideXlab platform.
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Dispatches Mycobacterium canettii, the Smooth Variant of M. tuberculosis, Isolated from a Swiss Patient Exposed in Africa
2013Co-Authors: Gaby E. Pfyffer, R. Auckenthaler, J. D. A. Van Embden, D. Van SoolingenAbstract:An exceptionally smooth and glossy morphotype of Mycobacterium tuberculosis complex was isolated from a 56-year-old Swiss patient with mesenteric tuberculosis. Direct 16S rRNA Sequence analysis of the hypervariable signature gene regions revealed a 100 % homology to the specific M. tuberculosis complex Sequence. Spoligotyping and restriction fragment length polymorphism analyses using the insertion Sequences IS6110 and IS1081 and the polymorphic GC-Rich Sequence as additional genetic markers identified the isolate as the novel taxon M. canettii. Like a Somali child with a similar case, this patient probably contracted the infection in Africa, which raises questions about the geographic distribution of M. canettii
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Mycobacterium canettii, the Smooth Variant of M. tuberculosis, Isolated from a Swiss Patient Exposed in Africa
Emerging infectious diseases, 1998Co-Authors: Gaby E. Pfyffer, R. Auckenthaler, J. D. A. Van Embden, D. Van SoolingenAbstract:An exceptionally smooth and glossy morphotype of Mycobacterium tuberculosis complex was isolated from a 56-year-old Swiss patient with mesenteric tuberculosis. Direct 16S rRNA Sequence analysis of the hypervariable signature gene regions revealed a 100% homology to the specific M. tuberculosis complex Sequence. Spoligotyping and restriction fragment length polymorphism analyses using the insertion Sequences IS6110 and IS1081 and the polymorphic GC-Rich Sequence as additional genetic markers identified the isolate as the novel taxon M. canettii. Like a Somali child with a similar case, this patient probably contracted the infection in Africa, which raises questions about the geographic distribution of M. canettii.
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predominance of a single genotype of mycobacterium tuberculosis in countries of east asia
Journal of Clinical Microbiology, 1995Co-Authors: D. Van Soolingen, Françoise Portaels, Lishi Qian, P E W De Haas, James T Douglas, Hamidou Traore, H Z Qing, D Enkhsaikan, Pagbajabyn Nymadawa, J. D. A. Van EmbdenAbstract:Analysis of the population structure of Mycobacterium tuberculosis strains from the People's Republic of China showed that the vast majority belong to a genetically closely related group. These strains shared the majority of their IS6110 DNA-containing restriction fragments, and also, the DNA polymorphism associated with other repetitive DNA elements, like the polymorphic GC-Rich Sequence and the direct repeat, was very limited. Because the majority of these strains originated from the province of Beijing, we designated this grouping the "Beijing family" of M. tuberculosis strains. Strains of this family were also found to dominate in neighboring countries such as Mongolia, South Korea, and Thailand, whereas a low prevalence of such strains was observed in countries on other continents. These data indicate that strains of the Beijing family recently expanded from a single ancestor which had a selective advantage. It is speculated that long-term Mycobacterium bovis BCG vaccination may be one of the selective forces implicated in the successful spread of the Beijing genotype.
Kohei Miyazono - One of the best experts on this subject based on the ideXlab platform.
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smad6 is a smad1 5 induced smad inhibitor characterization of bone morphogenetic protein responsive element in the mouse smad6 promoter
Journal of Biological Chemistry, 2000Co-Authors: Mitsuyasu Kato, Masahiro Kawabata, Wataru Ishida, Toshiaki Hamamoto, Kiyoshi Kusanagi, Ken Yagi, Kazuhiko Takehara, Kuber T Sampath, Kohei MiyazonoAbstract:Smad6 is an inhibitory Smad that is induced by bone morphogenetic proteins (BMPs) and interferes with BMP signaling. We have isolated the mouse Smad6 promoter and identified the regions responsible for transcriptional activation by BMPs. The proximal BMP-responsive element (PBE) in the Smad6 promoter is important for the transcriptional activation by BMPs and contains a 28-base pair GC-Rich Sequence including four overlapping copies of the GCCGnCGC-like motif, which is a binding site for DrosophilaMad and Medea. We generated a luciferase reporter construct (3GC2-Lux) containing three repeats of the GC-Rich Sequence derived from the PBE. BMPs and BMP receptors induced transcriptional activation of 3GC2-Lux in various cell types, and this activation was enhanced by cotransfection of BMP-responsive Smads, i.e. Smad1 or Smad5. Moreover, direct DNA binding of BMP-responsive Smads and common-partner Smad4 to the GC-Rich Sequence of PBE was observed. These results indicate that the expression of Smad6 is regulated by the effects of BMP-activated Smad1/5 on the Smad6promoter.
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Smad6 Is a Smad1/5-induced Smad Inhibitor CHARACTERIZATION OF BONE MORPHOGENETIC PROTEIN-RESPONSIVE ELEMENT IN THE MOUSE Smad6 PROMOTER
The Journal of biological chemistry, 2000Co-Authors: Wataru Ishida, Mitsuyasu Kato, Masahiro Kawabata, Toshiaki Hamamoto, Kiyoshi Kusanagi, Ken Yagi, Kazuhiko Takehara, T. Kuber Sampath, Kohei MiyazonoAbstract:Smad6 is an inhibitory Smad that is induced by bone morphogenetic proteins (BMPs) and interferes with BMP signaling. We have isolated the mouse Smad6 promoter and identified the regions responsible for transcriptional activation by BMPs. The proximal BMP-responsive element (PBE) in the Smad6 promoter is important for the transcriptional activation by BMPs and contains a 28-base pair GC-Rich Sequence including four overlapping copies of the GCCGnCGC-like motif, which is a binding site for DrosophilaMad and Medea. We generated a luciferase reporter construct (3GC2-Lux) containing three repeats of the GC-Rich Sequence derived from the PBE. BMPs and BMP receptors induced transcriptional activation of 3GC2-Lux in various cell types, and this activation was enhanced by cotransfection of BMP-responsive Smads, i.e. Smad1 or Smad5. Moreover, direct DNA binding of BMP-responsive Smads and common-partner Smad4 to the GC-Rich Sequence of PBE was observed. These results indicate that the expression of Smad6 is regulated by the effects of BMP-activated Smad1/5 on the Smad6promoter.
Wataru Ishida - One of the best experts on this subject based on the ideXlab platform.
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smad6 is a smad1 5 induced smad inhibitor characterization of bone morphogenetic protein responsive element in the mouse smad6 promoter
Journal of Biological Chemistry, 2000Co-Authors: Mitsuyasu Kato, Masahiro Kawabata, Wataru Ishida, Toshiaki Hamamoto, Kiyoshi Kusanagi, Ken Yagi, Kazuhiko Takehara, Kuber T Sampath, Kohei MiyazonoAbstract:Smad6 is an inhibitory Smad that is induced by bone morphogenetic proteins (BMPs) and interferes with BMP signaling. We have isolated the mouse Smad6 promoter and identified the regions responsible for transcriptional activation by BMPs. The proximal BMP-responsive element (PBE) in the Smad6 promoter is important for the transcriptional activation by BMPs and contains a 28-base pair GC-Rich Sequence including four overlapping copies of the GCCGnCGC-like motif, which is a binding site for DrosophilaMad and Medea. We generated a luciferase reporter construct (3GC2-Lux) containing three repeats of the GC-Rich Sequence derived from the PBE. BMPs and BMP receptors induced transcriptional activation of 3GC2-Lux in various cell types, and this activation was enhanced by cotransfection of BMP-responsive Smads, i.e. Smad1 or Smad5. Moreover, direct DNA binding of BMP-responsive Smads and common-partner Smad4 to the GC-Rich Sequence of PBE was observed. These results indicate that the expression of Smad6 is regulated by the effects of BMP-activated Smad1/5 on the Smad6promoter.
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Smad6 Is a Smad1/5-induced Smad Inhibitor CHARACTERIZATION OF BONE MORPHOGENETIC PROTEIN-RESPONSIVE ELEMENT IN THE MOUSE Smad6 PROMOTER
The Journal of biological chemistry, 2000Co-Authors: Wataru Ishida, Mitsuyasu Kato, Masahiro Kawabata, Toshiaki Hamamoto, Kiyoshi Kusanagi, Ken Yagi, Kazuhiko Takehara, T. Kuber Sampath, Kohei MiyazonoAbstract:Smad6 is an inhibitory Smad that is induced by bone morphogenetic proteins (BMPs) and interferes with BMP signaling. We have isolated the mouse Smad6 promoter and identified the regions responsible for transcriptional activation by BMPs. The proximal BMP-responsive element (PBE) in the Smad6 promoter is important for the transcriptional activation by BMPs and contains a 28-base pair GC-Rich Sequence including four overlapping copies of the GCCGnCGC-like motif, which is a binding site for DrosophilaMad and Medea. We generated a luciferase reporter construct (3GC2-Lux) containing three repeats of the GC-Rich Sequence derived from the PBE. BMPs and BMP receptors induced transcriptional activation of 3GC2-Lux in various cell types, and this activation was enhanced by cotransfection of BMP-responsive Smads, i.e. Smad1 or Smad5. Moreover, direct DNA binding of BMP-responsive Smads and common-partner Smad4 to the GC-Rich Sequence of PBE was observed. These results indicate that the expression of Smad6 is regulated by the effects of BMP-activated Smad1/5 on the Smad6promoter.
J. D. A. Van Embden - One of the best experts on this subject based on the ideXlab platform.
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Dispatches Mycobacterium canettii, the Smooth Variant of M. tuberculosis, Isolated from a Swiss Patient Exposed in Africa
2013Co-Authors: Gaby E. Pfyffer, R. Auckenthaler, J. D. A. Van Embden, D. Van SoolingenAbstract:An exceptionally smooth and glossy morphotype of Mycobacterium tuberculosis complex was isolated from a 56-year-old Swiss patient with mesenteric tuberculosis. Direct 16S rRNA Sequence analysis of the hypervariable signature gene regions revealed a 100 % homology to the specific M. tuberculosis complex Sequence. Spoligotyping and restriction fragment length polymorphism analyses using the insertion Sequences IS6110 and IS1081 and the polymorphic GC-Rich Sequence as additional genetic markers identified the isolate as the novel taxon M. canettii. Like a Somali child with a similar case, this patient probably contracted the infection in Africa, which raises questions about the geographic distribution of M. canettii
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Mycobacterium canettii, the Smooth Variant of M. tuberculosis, Isolated from a Swiss Patient Exposed in Africa
Emerging infectious diseases, 1998Co-Authors: Gaby E. Pfyffer, R. Auckenthaler, J. D. A. Van Embden, D. Van SoolingenAbstract:An exceptionally smooth and glossy morphotype of Mycobacterium tuberculosis complex was isolated from a 56-year-old Swiss patient with mesenteric tuberculosis. Direct 16S rRNA Sequence analysis of the hypervariable signature gene regions revealed a 100% homology to the specific M. tuberculosis complex Sequence. Spoligotyping and restriction fragment length polymorphism analyses using the insertion Sequences IS6110 and IS1081 and the polymorphic GC-Rich Sequence as additional genetic markers identified the isolate as the novel taxon M. canettii. Like a Somali child with a similar case, this patient probably contracted the infection in Africa, which raises questions about the geographic distribution of M. canettii.
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predominance of a single genotype of mycobacterium tuberculosis in countries of east asia
Journal of Clinical Microbiology, 1995Co-Authors: D. Van Soolingen, Françoise Portaels, Lishi Qian, P E W De Haas, James T Douglas, Hamidou Traore, H Z Qing, D Enkhsaikan, Pagbajabyn Nymadawa, J. D. A. Van EmbdenAbstract:Analysis of the population structure of Mycobacterium tuberculosis strains from the People's Republic of China showed that the vast majority belong to a genetically closely related group. These strains shared the majority of their IS6110 DNA-containing restriction fragments, and also, the DNA polymorphism associated with other repetitive DNA elements, like the polymorphic GC-Rich Sequence and the direct repeat, was very limited. Because the majority of these strains originated from the province of Beijing, we designated this grouping the "Beijing family" of M. tuberculosis strains. Strains of this family were also found to dominate in neighboring countries such as Mongolia, South Korea, and Thailand, whereas a low prevalence of such strains was observed in countries on other continents. These data indicate that strains of the Beijing family recently expanded from a single ancestor which had a selective advantage. It is speculated that long-term Mycobacterium bovis BCG vaccination may be one of the selective forces implicated in the successful spread of the Beijing genotype.
