24 results
Search Results
Now showing 1 - 10 of 24
Publication Metadata only Full Genomic Sequences of H5N1 Highly Pathogenic Avian Influenza Virus in Human Autopsy Specimens Reveal Genetic Variability and Adaptive Changes for Growth in MDCK Cell Cultures(2021-01-01) Kantima Sangsiriwut; Pirom Noisumdaeng; Mongkol Uiprasertkul; Jarunee Prasertsopon; Sunchai Payungporn; Prasert Auewarakul; Kumnuan Ungchusak; Pilaipan Puthavathana; Siriraj Hospital; Chulalongkorn University; Thailand Ministry of Public Health; Mahidol University; Thammasat Universitythat the adaptation changes for the viral fitness to survive in a new host species (MDCK cells) might involve many genes, for example, the amino acid substitution 177G or 177W adjacent to the receptor-binding residues in the HA1 globular head and the substitution M315Publication Metadata only Delayed antibody dependent enhancement of low passage dengue virus 4 isolates(2015-09-02) Nitwara Wikan; Sirikwan Libsittikul; Sutee Yoksan; Prasert Auewarakul; Duncan R. Smith; Mahidol University, particularly in regards to the behavior of low and high passage virus isolates. This study utilized two low passage DENV 4 isolates and a laboratory adapted DENV 4 isolate to investigate the potential of low passage isolates to undergo ADE. Results: Little... or no ADE of infection was observed on day 2 post infection with low passage isolates, while high enhancement of infection was seen with the laboratory adapted virus. However, both of the low passage isolates showed high levels of infection (60-100 %) by dayPublication Metadata only Expression of importin-α isoforms in human nasal mucosa: Implication for adaptation of avian influenza A viruses to human host(2016-06-04) Khwansiri Ninpan; Ornpreya Suptawiwat; Chompunuch Boonarkart; Peerayuht Phuangphung; Sakda Sathirareuangchai; Mongkol Uiprasertkul; Prasert Auewarakul; Mahidol University© 2016 The Author(s). Background: Transportation into the host cell nucleus is crucial for replication and transcription of influenza virus. The classical nuclear import is regulated by specific cellular factor, importin-α. Seven isoforms of importin-α have been identified in human. The preference of importin-α3 of avian influenza virus and -α7 isoform of human strains during replication in human cells was previously identified. In addition, both avian and human influenza viruses were shown to use importin-α1 isoform for their replication. Finding: The mRNA levels of importin-α1, -α3, and -α7 isoforms in human respiratory tract was determined by real-time RT-PCR. The results indicate that mRNA level of importin-α7 was significantly higher than that of importin-α1 (p-value < 0.0001) and importin-α3 (p-value < 0.0001) isoforms in human nasal mucosa while importin-α1 was detected as the highest expression importin-α isoform in lung tissues. Conclusions: These results may explain the preference of importin-α7 isoforms in seasonal influenza viruses in human upper respiratory tract and may suggest a selective pressure toward importin-α7 in human respiratory tract infection of an avian virus.Publication Metadata only Positive selection at the receptor-binding site of haemagglutinin H5 in viral sequences derived from human tissues(2008-08-01) Alita Kongchanagul; Ornpreya Suptawiwat; Pumaree Kanrai; Mongkol Uiprasertkul; Pilaipan Puthavathana; Prasert Auewarakul; Mahidol Universityof efficient transmission indicates the incompletion of the adaptation of the avian virus to the new host species. The required mutations for the complete adaptation and the emergence of a potential pandemic virus are likely to originate and be selected within... adaptation to a human host, and a new approach to search for new genetic markers of potential pandemic viruses. © 2008 SGM.Publication Metadata only Identification of Hsp90 as a species independent H5N1 avian influenza A virus PB2 interacting protein(2015-12-01) Krit Jirakanwisal; Kanjana Srisutthisamphan; Chutima Thepparit; Ornpreya Suptawiwat; Prasert Auewarakul; Atchara Paemanee; Sittiruk Roytrakul; Duncan R. Smith; Mahidol University; Thailand National Science and Technology Development Agency© 2015 Elsevier Ltd. The avian influenza polymerase protein PB2 subunit is an important mediator of cross species adaptation and adaptation to mammalian cells is strongly but not exclusively associated with an adaptive mutation of the codonPublication Open Access Delayed antibody dependent enhancement of low passage dengue virus 4 isolates(2015) Nitwara Wikan; Sirikwan Libsittikul; Sutee Yoksan; Prasert Auewarakul; Duncan R. Smith; Mahidol University. Institute of Molecular Biosciencesto the behavior of low and high passage virus isolates. This study utilized two low passage DENV 4 isolates and a laboratory adapted DENV 4 isolate to investigate the potential of low passage isolates to undergo ADE. Results: Little or no ADE of infection... was observed on day 2 post infection with low passage isolates, while high enhancement of infection was seen with the laboratory adapted virus. However, both of the low passage isolates showed high levels of infection (60–100 %) by day 5 post infectionPublication Metadata only Cloned cDNA of A/swine/Iowa/15/1930 internal genes as a candidate backbone for reverse genetics vaccine against influenza A viruses(2012-02-14) Porntippa Lekcharoensuk; Witthawat Wiriyarat; Nantawan Petcharat; Chalermpol Lekcharoensuk; Prasert Auewarakul; Juergen A. Richt; Kasetsart University; Mahidol University; Kansas State UniversityReverse genetics viruses for influenza vaccine production usually utilize the internal genes of the egg-adapted A/Puerto Rico/8/34 (PR8) strain. This egg-adapted strain provides high production yield in embryonated eggs but does not necessarily give... the best yield in mammalian cell culture. In order to generate a reverse genetics viral backbone that is well-adapted to high growth in mammalian cell culture, a swine influenza isolate A/swine/Iowa/15/30 (H1N1) (rg1930) that was shown to give high yieldPublication Open Access Substrate specificity of avian influenza H5N1 neuraminidase(2014-11-12) Naruthai Onsirisakul; Nakakita, Shin-ichi; Chompunuch Boonarkart; Alita Kongchanagul; Ornpreya Suptawiwat; Pilaipan Puthavathana; Krisada Chaichuen; Kanokwan Kittiniyom; Suzuki, Yasuo; Prasert Auewarakul; Mahidol University. Faculty of Medical Technology. Department of Clinical Microbiology and Applied Technology; Mahidol University. Faculty of Veterinary Science; Mahidol Univeristy. Faculty of Medicine Siriraj Hospital. Department of Microbiology.; Mahidol University. Institute of Molecular Biosciences. Similar to Amplex red assay, H5N1 virus showed abundant preference on α2,3-linked sialic acid. CONCLUSION: H5N1 virus maintains the avian specific NA and NA changes may be needed to accompany changes in HA receptor preference for the viral adaptationPublication Open Access Expression of importin-α isoforms in human nasal mucosa: implication for adaptation of avian influenza A viruses to human host(2016) Khwansiri Ninpan; Ornpreya Suptawiwat; Chompunuch Boonarkart; Peerayuht Phuangphung; Sakda Sathirareuangchai; Mongkol Uiprasertkul; Prasert Auewarakul; Mahidol University. Faculty of Medicine Siriraj Hospital. Department of MicrobiologyBackground: Transportation into the host cell nucleus is crucial for replication and transcription of influenza virus. The classical nuclear import is regulated by specific cellular factor, importin-α. Seven isoforms of importin-α have been identified in human. The preference of importin-α3 of avian influenza virus and -α7 isoform of human strains during replication in human cells was previously identified. In addition, both avian and human influenza viruses were shown to use importin-α1 isoform for their replication. Finding: The mRNA levels of importin-α1, −α3, and –α7 isoforms in human respiratory tract was determined by real-time RT-PCR. The results indicate that mRNA level of importin-α7 was significantly higher than that of importin-α1 (p-value < 0.0001) and importin-α3 (p-value < 0.0001) isoforms in human nasal mucosa while importin-α1 was detected as the highest expression importin-α isoform in lung tissues. Conclusions: These results may explain the preference of importin-α7 isoforms in seasonal influenza viruses in human upper respiratory tract and may suggest a selective pressure toward importin-α7 in human respiratory tract infection of an avian virus.Publication Metadata only Codon usage of HIV regulatory genes is not determined by nucleotide composition(2018-02-01) Supinya Phakaratsakul; Thanyaporn Sirihongthong; Chompunuch Boonarkart; Ornpreya Suptawiwat; Prasert Auewarakul; Faculty of Medicine, Siriraj Hospital, Mahidol University; Chulabhorn Royal Academyand env). However, the codon usage of the regulatory genes (tat and rev) could not be predicted. Codon usage of the regulatory genes was also relatively unbiased showing the highest effective number of codons (ENC). Moreover, the codon adaptation index... (CAI) of the regulatory genes showed better adaptation to human codons when compared to other HIV genes. Therefore, the early expressed genes responsible for regulation of the replication cycle, tat and rev, were more similar to humans in terms of codon
- «
- 1 (current)
- 2
- 3
- »