The Experts below are selected from a list of 36837 Experts worldwide ranked by ideXlab platform

Hiroaki Okamoto - One of the best experts on this subject based on the ideXlab platform.

  • genetic variability and evolution of hepatitis e virus
    Virus Research, 2007
    Co-Authors: Hiroaki Okamoto
    Abstract:

    Hepatitis E virus (HEV) is the sole member of the genus Hepevirus in the family Hepeviridae. HEV is transmitted primarily by the Fecal-Oral Route, and water-borne epidemics are characteristic of hepatitis E in many developing countries in Asia, Africa and Latin America where sanitation conditions are suboptimal. Accumulating lines of evidence indicate that HEV-associated hepatitis also occurs domestically among individuals in industrialized countries, that there are animal reservoirs of HEV such as domestic pigs and wild boars, and that hepatitis E is a zoonosis. Based on the extensive genomic variability among HEV isolates, HEV sequences have been classified into four genotypes: genotype 1 consists of epidemic strains in developing countries in Asia and Africa; genotype 2 has been described in Mexico and several African countries; genotype 3 HEV is widely distributed and has been isolated from sporadic cases of acute hepatitis E and/or domestic pigs in many countries in the world, except for countries in Africa; and genotype 4 contains strains isolated from humans and/or domestic pigs exclusively in Asian countries. This paper reviews current knowledge on the genomic variability, geographic distribution and zoonotic aspects of HEV as well as the clinical significance of genotype and evolution of HEV.

  • fecal excretion of a nonenveloped dna virus ttv associated with posttransfusion non a g hepatitis
    Journal of Medical Virology, 1998
    Co-Authors: Hiroaki Okamoto, Yoshihiro Akahane, Masato Ukita, Masako Fukuda, Fumio Tsuda, Yuzo Miyakawa, Makoto Mayumi
    Abstract:

    Five patients with type B or C hepatocellular carcinoma were found to be infected with a nonenveloped DNA virus (TTV) associated with posttransfusion hepatitis of non-A-G etiology. Paired feces and serum samples from these patients were tested for TTV DNA by polymerase chain reaction with seminested primers and their sequences were compared. TTV DNA was detected in sera from all of the patients, while it was detected in feces from three patients, including two with high viral titers in serum. When feces and serum from one patient were subjected to floatation ultracentrifugation in CsCl, TTV in feces banded at a peak density of 1.35 g/cm3 and that in serum at 1.31-1.32 g/cm3. TTV isolates in three pairs of feces and serum had the identical sequence of 222 base pairs. The excretion of TTV into feces indicates that TTV would be transmitted not only parenterally but also nonparenterally by a Fecal-Oral Route.

  • fecal excretion of a nonenveloped dna virus ttv associated with posttransfusion non a g hepatitis
    Journal of Medical Virology, 1998
    Co-Authors: Hiroaki Okamoto, Yoshihiro Akahane, Masato Ukita, Masako Fukuda, Fumio Tsuda, Yuzo Miyakawa, Makoto Mayumi
    Abstract:

    Five patients with type B or C hepatocellular carcinoma were found to be infected with a nonenveloped DNA virus (TTV) associated with posttransfusion hepatitis of non-A–G etiology. Paired feces and serum samples from these patients were tested for TTV DNA by polymerase chain reaction with seminested primers and their sequences were compared. TTV DNA was detected in sera from all of the patients, while it was detected in feces from three patients, including two with high viral titers in serum. When feces and serum from one patient were subjected to floatation ultracentrifugation in CsCl, TTV in feces banded at a peak density of 1.35 g/cm3 and that in serum at 1.31–1.32 g/cm3. TTV isolates in three pairs of feces and serum had the identical sequence of 222 base pairs. The excretion of TTV into feces indicates that TTV would be transmitted not only parenterally but also nonparenterally by a fecal–oral Route. J. Med. Virol. 56:128–132, 1998. © 1998 Wiley-Liss, Inc.

Makoto Mayumi - One of the best experts on this subject based on the ideXlab platform.

  • fecal excretion of a nonenveloped dna virus ttv associated with posttransfusion non a g hepatitis
    Journal of Medical Virology, 1998
    Co-Authors: Hiroaki Okamoto, Yoshihiro Akahane, Masato Ukita, Masako Fukuda, Fumio Tsuda, Yuzo Miyakawa, Makoto Mayumi
    Abstract:

    Five patients with type B or C hepatocellular carcinoma were found to be infected with a nonenveloped DNA virus (TTV) associated with posttransfusion hepatitis of non-A-G etiology. Paired feces and serum samples from these patients were tested for TTV DNA by polymerase chain reaction with seminested primers and their sequences were compared. TTV DNA was detected in sera from all of the patients, while it was detected in feces from three patients, including two with high viral titers in serum. When feces and serum from one patient were subjected to floatation ultracentrifugation in CsCl, TTV in feces banded at a peak density of 1.35 g/cm3 and that in serum at 1.31-1.32 g/cm3. TTV isolates in three pairs of feces and serum had the identical sequence of 222 base pairs. The excretion of TTV into feces indicates that TTV would be transmitted not only parenterally but also nonparenterally by a Fecal-Oral Route.

  • fecal excretion of a nonenveloped dna virus ttv associated with posttransfusion non a g hepatitis
    Journal of Medical Virology, 1998
    Co-Authors: Hiroaki Okamoto, Yoshihiro Akahane, Masato Ukita, Masako Fukuda, Fumio Tsuda, Yuzo Miyakawa, Makoto Mayumi
    Abstract:

    Five patients with type B or C hepatocellular carcinoma were found to be infected with a nonenveloped DNA virus (TTV) associated with posttransfusion hepatitis of non-A–G etiology. Paired feces and serum samples from these patients were tested for TTV DNA by polymerase chain reaction with seminested primers and their sequences were compared. TTV DNA was detected in sera from all of the patients, while it was detected in feces from three patients, including two with high viral titers in serum. When feces and serum from one patient were subjected to floatation ultracentrifugation in CsCl, TTV in feces banded at a peak density of 1.35 g/cm3 and that in serum at 1.31–1.32 g/cm3. TTV isolates in three pairs of feces and serum had the identical sequence of 222 base pairs. The excretion of TTV into feces indicates that TTV would be transmitted not only parenterally but also nonparenterally by a fecal–oral Route. J. Med. Virol. 56:128–132, 1998. © 1998 Wiley-Liss, Inc.

Christine M Rippinger - One of the best experts on this subject based on the ideXlab platform.

  • murine norovirus propagation quantification and genetic manipulation
    Current protocols in microbiology, 2014
    Co-Authors: Seungmin Hwang, Abimbola O Kolawole, Juliana Bragazzi Cunha, Armando Arias, Bader Alhatlani, Sarah Caddy, Constantina Christodoulou, Edward Emmott, Marta J Gonzalezhernandez, Christine M Rippinger
    Abstract:

    Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. It is the most common pathogen in biomedical research colonies. MNV is also related to the human noroviruses, which cause the majority of non-bacterial gastroenteritis worldwide. Like the human noroviruses, MNV is an enteric virus that replicates in the intestine and is transmitted by the Fecal-Oral Route. MNV replicates in murine macrophages and dendritic cells in cells in culture and in the murine host. This virus is often used to study mechanisms in norovirus biology, because the human noroviruses are refractory to growth in cell culture. MNV combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Herein, we describe a panel of techniques that are commonly used to study MNV biology.

  • murine norovirus propagation quantification and genetic manipulation
    Current protocols in microbiology, 2014
    Co-Authors: Seungmin Hwang, Abimbola O Kolawole, Juliana Bragazzi Cunha, Armando Arias, Bader Alhatlani, Sarah Caddy, Constantina Christodoulou, Edward Emmott, Marta J Gonzalezhernandez, Christine M Rippinger
    Abstract:

    Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. It is the most common pathogen in biomedical research colonies. MNV is also related to the human noroviruses, which cause the majority of nonbacterial gastroenteritis worldwide. Like the human noroviruses, MNV is an enteric virus that replicates in the intestine and is transmitted by the Fecal-Oral Route. MNV replicates in murine macrophages and dendritic cells in cells in culture and in the murine host. This virus is often used to study mechanisms in norovirus biology, because human noroviruses are refractory to growth in cell culture. MNV combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Herein, we describe a panel of techniques that are commonly used to study MNV biology.

Seungmin Hwang - One of the best experts on this subject based on the ideXlab platform.

  • murine norovirus propagation quantification and genetic manipulation
    Current protocols in microbiology, 2014
    Co-Authors: Seungmin Hwang, Abimbola O Kolawole, Juliana Bragazzi Cunha, Armando Arias, Bader Alhatlani, Sarah Caddy, Constantina Christodoulou, Edward Emmott, Marta J Gonzalezhernandez, Christine M Rippinger
    Abstract:

    Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. It is the most common pathogen in biomedical research colonies. MNV is also related to the human noroviruses, which cause the majority of non-bacterial gastroenteritis worldwide. Like the human noroviruses, MNV is an enteric virus that replicates in the intestine and is transmitted by the Fecal-Oral Route. MNV replicates in murine macrophages and dendritic cells in cells in culture and in the murine host. This virus is often used to study mechanisms in norovirus biology, because the human noroviruses are refractory to growth in cell culture. MNV combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Herein, we describe a panel of techniques that are commonly used to study MNV biology.

  • murine norovirus propagation quantification and genetic manipulation
    Current protocols in microbiology, 2014
    Co-Authors: Seungmin Hwang, Abimbola O Kolawole, Juliana Bragazzi Cunha, Armando Arias, Bader Alhatlani, Sarah Caddy, Constantina Christodoulou, Edward Emmott, Marta J Gonzalezhernandez, Christine M Rippinger
    Abstract:

    Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. It is the most common pathogen in biomedical research colonies. MNV is also related to the human noroviruses, which cause the majority of nonbacterial gastroenteritis worldwide. Like the human noroviruses, MNV is an enteric virus that replicates in the intestine and is transmitted by the Fecal-Oral Route. MNV replicates in murine macrophages and dendritic cells in cells in culture and in the murine host. This virus is often used to study mechanisms in norovirus biology, because human noroviruses are refractory to growth in cell culture. MNV combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Herein, we describe a panel of techniques that are commonly used to study MNV biology.

Marisol Cordova - One of the best experts on this subject based on the ideXlab platform.

  • seroprevalence of triatoma virus dicistroviridae cripaviridae antibodies in chagas disease patients
    Parasites & Vectors, 2015
    Co-Authors: Jailson Brito Querido, Gerardo Anibal Marti, María Laura Susevich, María Gabriela Echeverría, Rita Costa, Jorge E Rabinovich, Aydee Copa, Nair A Montano, Lineth Garcia, Marisol Cordova
    Abstract:

    Chagas disease is caused by Trypanosoma cruzi, and humans acquire the parasite by exposure to contaminated feces from hematophagous insect vectors known as triatomines. Triatoma virus (TrV) is the sole viral pathogen of triatomines, and is transmitted among insects through the Fecal-Oral Route and, as it happens with T. cruzi, the infected insects release the virus when defecating during or after blood uptake. In this work, we analysed the occurrence of anti-TrV antibodies in human sera from Chagas disease endemic and non-endemic countries, and developed a mathematical model to estimate the transmission probability of TrV from insects to man, which ranged between 0.00053 and 0.0015. Our results confirm that people with Chagas disease living in Bolivia, Argentina and Mexico have been exposed to TrV, and that TrV is unable to replicate in human hosts. We presented the first experimental evidence of antibodies against TrV structural proteins in human sera.