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Monique França

Bio: Monique França is an academic researcher from University of Georgia. The author has contributed to research in topics: Influenza A virus subtype H5N1 & Virus. The author has an hindex of 14, co-authored 41 publications receiving 648 citations. Previous affiliations of Monique França include Federal University of Rio de Janeiro & University of California, Davis.

Papers
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Journal ArticleDOI
TL;DR: Pyrosequencing of cDNA from brains of parrots with proventricular dilatation disease showed 2 strains of a novel Borna virus, which confirmed virus presence in brain, proventriculus, and adrenal gland of 3 birds with PDD but not in 4 unaffected birds.
Abstract: Pyrosequencing of cDNA from brains of parrots with proventricular dilatation disease (PDD), an unexplained fatal inflammatory central, autonomic, and peripheral nervous system disease, showed 2 strains of a novel Borna virus. Real-time PCR confirmed virus presence in brain, proventriculus, and adrenal gland of 3 birds with PDD but not in 4 unaffected birds.

205 citations

Journal ArticleDOI
TL;DR: In this paper, the expression of α2,3-linked and α 2,6-linked sialic acid (SA) influenza virus receptors in tissues is considered one of the determinants of the host range and tissue tropism of influenza viruses.
Abstract: Avian influenza (AI) viruses have been detected in more than 105 wild bird species from 12 different orders but species-related differences in susceptibility to AI viruses exist. Expression of α2,3-linked (avian-type) and α2,6-linked (human-type) sialic acid (SA) influenza virus receptors in tissues is considered one of the determinants of the host range and tissue tropism of influenza viruses. We investigated the expression of these SA receptors in 37 wild bird species from 11 different orders by lectin histochemistry. Two isoforms of Maackia amurensis (MAA) lectin, MAA1 and MAA2, were used to detect α2,3-linked SA, and Sambucus nigra lectin was used to detect α2,6-linked SA. All species evaluated expressed α2,3-linked and α2,6-linked SA receptors in endothelial cells and renal tubular epithelial cells. Both α2,3-linked and α-2,6-linked SA receptors were expressed in respiratory and intestinal tract tissues of aquatic and terrestrial wild bird species from different taxa, but differences in SA expression and in the predominant isoform of MAA lectin bound were observed. With a few possible exceptions, these observed differences were not generally predictive of reported species susceptibility to AI viruses based on published experimental and field data.

63 citations

Book ChapterDOI
TL;DR: The pathogenesis of AI is complex and the ability of these viruses to produce disease and death in avian species is dependent on various host, viral and environmental factors, which are not completely understood.
Abstract: Wild birds in the orders Anseriformes and Charadriiformes are the natural and asymptomatic reservoirs of influenza A viruses representing all of the avian hemagglutinin (HA) and neuraminidase (NA) subtypes. Transmission of avian influenza (AI) viruses from wild birds to gallinaceous poultry species occurs regularly and outcomes vary, ranging from asymptomatic infections to mortality. Circulation of H5 and H7 low pathogenic AI (LPAI) viruses in gallinaceous poultry may result in mutations in the HA protein cleavage site and the emergence of highly pathogenic AI (HPAI) viruses, which in poultry can cause severe disease with high economic losses. Since 2002, various wild bird species also have succumbed to infection with the Eurasian H5N1 HPAI viruses. The pathogenesis of AI is complex and the ability of these viruses to produce disease and death in avian species is dependent on various host, viral and environmental factors, which are not completely understood.

43 citations

Journal ArticleDOI
TL;DR: Experimental infections in mallard ducks provide new insights into within-host IAV complex interactions as drivers of IAV antigenic diversity that could allow the circulation of multiple subtypes in wild ducks.
Abstract: Our overall hypothesis is that host population immunity directed at multiple antigens will influence the prevalence, diversity and evolution of influenza A virus (IAV) in avian populations where the vast subtype diversity is maintained. To investigate how initial infection influences the outcome of later infections with homologous or heterologous IAV subtypes and how viruses interact through host immune responses, we carried out experimental infections in mallard ducks (Anas platyrhynchos). Mallards were pre-challenged with an H3N8 low-pathogenic IAV and were divided into six groups. At five weeks post H3N8 inoculation, each group was challenged with a different IAV subtype (H4N5, H10N7, H6N2, H12N5) or the same H3N8. Two additional pre-challenged groups were inoculated with the homologous H3N8 virus at weeks 11 and 15 after pre-challenge to evaluate the duration of protection. The results showed that mallards were still resistant to re-infection after 15 weeks. There was a significant reduction in shedding for all pre-challenged groups compared to controls and the outcome of the heterologous challenges varied according to hemagglutinin (HA) phylogenetic relatedness between the viruses used. There was a boost in the H3 antibody titer after re-infection with H4N5, which is consistent with original antigenic sin or antigenic seniority and suggest a putative strategy of virus evasion. These results imply competition between related subtypes that could regulate IAV subtype population dynamics in nature. Collectively, we provide new insights into within-host IAV complex interactions as drivers of IAV antigenic diversity that could allow the circulation of multiple subtypes in wild ducks.

42 citations

Journal ArticleDOI
TL;DR: The results suggest that dietary supplementation with FOS may impair SE pathogenesis while modulating humoral immunity within the gut‐associated lymphoid tissue.

34 citations


Cited by
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01 Jun 2012
TL;DR: SPAdes as mentioned in this paper is a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler and on popular assemblers Velvet and SoapDeNovo (for multicell data).
Abstract: The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.

10,124 citations

Journal ArticleDOI
01 Mar 1941-Nature
TL;DR: In this article, Gray has written a book on diseases of poultry, Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl.
Abstract: VERY few veterinary surgeons have thought fit to write a book on diseases of poultry. Mr. Ernest Gray has done justice to the subject and is to be congratulated on his effort. A book of this size, written by one with specialized knowledge, will add to the value of any library or private bookshelf. Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl. By Ernest Gray. (Lockwood's Agricultural and Horticultural Handbooks.) Pp. x + 198 + 16 plates. (London: Crosby Lockwood and Son, Ltd., 1940.) 9s. 6d. net.

1,282 citations

01 Jan 2000
TL;DR: A type III protein secretion system encoded by Salmonella pathogenicity island 2 (SPI2) has been found to be required for virulence and survival within macrophages as discussed by the authors.
Abstract: A type III protein secretion system encoded by Salmonella pathogenicity island 2 (SPI2) has been found to be required for virulence and survival within macrophages. Here, SPI2 was shown to allow Salmonella typhimurium to avoid NADPH oxidase-dependent killing by macrophages. The ability of SPI2-mutant bacteria to survive in macrophages and to cause lethal infection in mice was restored by abrogation of the NADPH oxidase-dependent respiratory burst. Ultrastructural and immunofluorescence microscopy demonstrated efficient localization of the NADPH oxidase in the proximity of vacuoles containing SPI2-mutant but not wild-type bacteria, suggesting that SPI2 interferes with trafficking of oxidase-containing vesicles to the phagosome.

531 citations

Journal ArticleDOI
TL;DR: The potential of metagenomics for characterization of the normal viral population in a healthy community and identification of viruses that could pose a threat to humans through zoonosis is discussed and a new model of the Koch's postulates named the ‘Metagenomic Koch's Postulates’ is proposed.

518 citations

Journal ArticleDOI
TL;DR: Recent data on the interaction between influenza virus HA and SA receptors of the host, and the impact on virus host range, pathogenesis, and transmission are reviewed and remaining challenges and future research priorities are discussed.
Abstract: The recent emergence of a novel avian A/H7N9 influenza virus in poultry and humans in China, as well as laboratory studies on adaptation and transmission of avian A/H5N1 influenza viruses, has shed new light on influenza virus adaptation to mammals. One of the biological traits required for animal influenza viruses to cross the species barrier that received considerable attention in animal model studies, in vitro assays, and structural analyses is receptor binding specificity. Sialylated glycans present on the apical surface of host cells can function as receptors for the influenza virus hemagglutinin (HA) protein. Avian and human influenza viruses typically have a different sialic acid (SA)-binding preference and only few amino acid changes in the HA protein can cause a switch from avian to human receptor specificity. Recent experiments using glycan arrays, virus histochemistry, animal models, and structural analyses of HA have added a wealth of knowledge on receptor binding specificity. Here, we review recent data on the interaction between influenza virus HA and SA receptors of the host, and the impact on virus host range, pathogenesis, and transmission. Remaining challenges and future research priorities are also discussed.

336 citations