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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Development of an Antibiotic Resistance Free Bivalent Vaccine Against Swine Brucellosis and Swine Influenza

Rajasekaran, Parthiban 10 February 2010 (has links)
Livestock across the world contract several infectious diseases of both bacterial and viral origin. Swine brucellosis caused by Brucella suis and swine influenza caused by Influenza A virus affect both domestic and feral swine populations. Both the diseases have zoonotic potential to cause disease in humans with serious complications apart from inflicting huge economic losses. Infected feral swine can also act as a source of spread and outbreak where the disease is not endemic. At present, there is no vaccine available for swine brucellosis. The currently used swine influenza vaccine may not be effective against influenza strains like the recent H1N1 strain that caused a pandemic. To develop an effective bivalent vaccine for swine against these two diseases, a leucine auxotroph of the USDA approved vaccine B. abortus strain RB51 was constructed along with leuB gene complementing plasmid pNS4 to over-express antigens from Brucella and influenza. This antibiotic resistance free system over-expressed Brucella derived antigens SOD, L7/L12 and WboA in three different constructs. Against a virulent challenge of B. suis, the candidate vaccine strain over-expressing both SOD and WboA protected mice more significantly than the control group and was also found to be better protective than other candidate vaccine strains over-expressing either SOD and L7/L12 together or SOD alone. Immunoassays (ELISA) suggested that the protection afforded is Th1 type mediated immune response, as cytokine IFN-γ and IgG2a antibody sub-isotype was observed in the splenocyte culture supernatant and serum samples respectively. The strain RB51leuB platform was not expressing influenza derived antigens Hemagglutinin (HA) and Nucleoprotein (NP) when screened for expression by immunoblot. Influenza antigens, HA, NP and ectodomain of matrix protein M2e, were not found to be expressing even after optimizing their codon usage to suit Brucella tRNA preference. However, RT-PCR showed that the influenza genes mRNA were produced. In conclusion, this dissertation describes the construction of an environmentally safe antigen over-expression platform and successful employment of the system as a candidate vaccine in protecting mice against B. suis challenge. This new platform is a potential candidate for developing vaccines against other infectious diseases of livestock. This document also discusses alternate strategies for expressing influenza antigens in a Brucella platform. / Ph. D.
22

Estudo etiológico e patológico de pneumonias em javalis criados de forma confinada no estado do Rio Grande do Sul / Etiological and pathological study of pneumonia in captive wild-boars in the state of Rio Grande do Sul

Biondo, Natalha January 2012 (has links)
As doenças respiratórias são muito comuns na produção intensiva de suínos, já em javalis são escassas informações sobre prevalência, etiologia e apresentação clínico-patológica destas enfermidades. No entanto, a presença de patógenos respiratórios comuns entre javalis selvagens e confinados e suínos domésticos já foi relatada. Este trabalho descreve as principais lesões macroscópicas e histológicas de pneumonias de javalis e os agentes comumente envolvidos. Foram examinados pulmões de javalis, ao abate, provenientes de criatórios comerciais e a principal lesão macroscópica foi consolidação crânio-ventral dos lobos craniais e médios e lesões crônicas cursando com hiperplasia linfóide na histologia. O principal agente bacteriano detectado foi o Mycoplasma hyopneumoniae (58,6%). Outros patógenos bacterianos detectados foram Actinobacillus pleuropneumoniae (48,8%), Haemophilus parasuis (49,6%), Mycoplasma hyorhinis (41,3%), Pasteurella multocida (9,1%) e Streptococcus suis (9,1%). Na segunda parte do trabalho, a pesquisa de patógenos virais foi direcionada para o Vírus da influenza suína (VIS) com objetivo de estudar o envolvimento em pneumonias de javalis de criatórios e a relação com agentes bacterianos encontrados. O vírus pandêmico A/H1N1/2009 foi detectado em 18,3% (11/60) e sua identidade foi confirmada por sequenciamento. A carga viral para H1N1 clássico variou de 4,58 a 6275 cópias/μL e para o H1N1 pandêmico, de 4,65 a 3863 cópias/μL. Nenhuma amostra apresentou título viral após a inoculação em ovos embrionados. As lesões histológicas principais foram broncopneumonia crônica difusa e pneumonia intersticial mononuclear leve, além de hiperplasia linfóide. As amostras positivas por RT-PCR para o VIS para o pH1N1 foram testadas por IHQ, sendo todas negativas para influenza A, mas todas eram positivas para M. hyopneumoniae. Quando testadas por bacteriologia, 18,2% das amostras foram positivas para P. multocida. O estudo mostrou que as pneumonias em javalis de criatório apresentaram lesões e patógenos associados similares aos encontrados em suínos domésticos ao abate. Este é o primeiro relato da infecção pelo vírus pH1N1 em javalis no Brasil. / Respiratory diseases are very common in swine intensive production, although in wild-boars the knowledge of the prevalence, etiology and clinic-pathological presentation of these diseases are very limited. However, the presence of common respiratory pathogens among wild-boar, captive wild-boar and domestic pigs has been reported. This paper describes the main macroscopic and histologic pneumonic lesions of captive wild-boars and pathogens commonly involved. Captive wild-boar lungs at slaughter were examined and the main macroscopic lesion observed was cranio-ventral consolidation of cranial and middle lobes and chronic lesions associated with lymphoid hyperplasia by histology. The main bacterial pathogen detected was Mycoplasma hyopneumoniae (58.6%). Other bacterial pathogens detected were Actinobacillus pleuropneumoniae (48.8%), Haemophilus parasuis (49.6%), Mycoplasma hyorhinis (41.3%), Pasteurella multocida (9.1%) and Streptococcus suis (9.1%). In the second part of this work, the survey of viral pathogens was directed to swine influenza virus (SIV) in order to study the involvement in captive wild-boar pneumonias and the relation with bacterial pathogens. The A/H1N1/2009 pandemic virus was detected in 18.3% (11/60) and its identity was confirmed by sequencing. The classical H1N1 viral load ranged from 4.58 to 6275 copies/uL and the pandemic H1N1, from 4.65 to 3863 copies/uL. No samples had viral titers after inoculation in embryonated eggs. The main histological lesions were chronic diffuse bronchopneumonia and interstitial mononuclear pneumonia as well as mild lymphoid hyperplasia. Samples positive to pH1N1 were assayed by IHC for SIV, all with negative results, and to M. hyopneumoniae, all were positive. When assayed by bacteriology, 18.2% of samples were positive to P. multocida. This study showed that pneumonia in captive wild-boar had similar lesions and associated pathogens were similar to those found in domestic pigs at slaughter. This is the first report of pH1N1 virus infection in captive wild-boars in Brazil.
23

Estudo etiológico e patológico de pneumonias em javalis criados de forma confinada no estado do Rio Grande do Sul / Etiological and pathological study of pneumonia in captive wild-boars in the state of Rio Grande do Sul

Biondo, Natalha January 2012 (has links)
As doenças respiratórias são muito comuns na produção intensiva de suínos, já em javalis são escassas informações sobre prevalência, etiologia e apresentação clínico-patológica destas enfermidades. No entanto, a presença de patógenos respiratórios comuns entre javalis selvagens e confinados e suínos domésticos já foi relatada. Este trabalho descreve as principais lesões macroscópicas e histológicas de pneumonias de javalis e os agentes comumente envolvidos. Foram examinados pulmões de javalis, ao abate, provenientes de criatórios comerciais e a principal lesão macroscópica foi consolidação crânio-ventral dos lobos craniais e médios e lesões crônicas cursando com hiperplasia linfóide na histologia. O principal agente bacteriano detectado foi o Mycoplasma hyopneumoniae (58,6%). Outros patógenos bacterianos detectados foram Actinobacillus pleuropneumoniae (48,8%), Haemophilus parasuis (49,6%), Mycoplasma hyorhinis (41,3%), Pasteurella multocida (9,1%) e Streptococcus suis (9,1%). Na segunda parte do trabalho, a pesquisa de patógenos virais foi direcionada para o Vírus da influenza suína (VIS) com objetivo de estudar o envolvimento em pneumonias de javalis de criatórios e a relação com agentes bacterianos encontrados. O vírus pandêmico A/H1N1/2009 foi detectado em 18,3% (11/60) e sua identidade foi confirmada por sequenciamento. A carga viral para H1N1 clássico variou de 4,58 a 6275 cópias/μL e para o H1N1 pandêmico, de 4,65 a 3863 cópias/μL. Nenhuma amostra apresentou título viral após a inoculação em ovos embrionados. As lesões histológicas principais foram broncopneumonia crônica difusa e pneumonia intersticial mononuclear leve, além de hiperplasia linfóide. As amostras positivas por RT-PCR para o VIS para o pH1N1 foram testadas por IHQ, sendo todas negativas para influenza A, mas todas eram positivas para M. hyopneumoniae. Quando testadas por bacteriologia, 18,2% das amostras foram positivas para P. multocida. O estudo mostrou que as pneumonias em javalis de criatório apresentaram lesões e patógenos associados similares aos encontrados em suínos domésticos ao abate. Este é o primeiro relato da infecção pelo vírus pH1N1 em javalis no Brasil. / Respiratory diseases are very common in swine intensive production, although in wild-boars the knowledge of the prevalence, etiology and clinic-pathological presentation of these diseases are very limited. However, the presence of common respiratory pathogens among wild-boar, captive wild-boar and domestic pigs has been reported. This paper describes the main macroscopic and histologic pneumonic lesions of captive wild-boars and pathogens commonly involved. Captive wild-boar lungs at slaughter were examined and the main macroscopic lesion observed was cranio-ventral consolidation of cranial and middle lobes and chronic lesions associated with lymphoid hyperplasia by histology. The main bacterial pathogen detected was Mycoplasma hyopneumoniae (58.6%). Other bacterial pathogens detected were Actinobacillus pleuropneumoniae (48.8%), Haemophilus parasuis (49.6%), Mycoplasma hyorhinis (41.3%), Pasteurella multocida (9.1%) and Streptococcus suis (9.1%). In the second part of this work, the survey of viral pathogens was directed to swine influenza virus (SIV) in order to study the involvement in captive wild-boar pneumonias and the relation with bacterial pathogens. The A/H1N1/2009 pandemic virus was detected in 18.3% (11/60) and its identity was confirmed by sequencing. The classical H1N1 viral load ranged from 4.58 to 6275 copies/uL and the pandemic H1N1, from 4.65 to 3863 copies/uL. No samples had viral titers after inoculation in embryonated eggs. The main histological lesions were chronic diffuse bronchopneumonia and interstitial mononuclear pneumonia as well as mild lymphoid hyperplasia. Samples positive to pH1N1 were assayed by IHC for SIV, all with negative results, and to M. hyopneumoniae, all were positive. When assayed by bacteriology, 18.2% of samples were positive to P. multocida. This study showed that pneumonia in captive wild-boar had similar lesions and associated pathogens were similar to those found in domestic pigs at slaughter. This is the first report of pH1N1 virus infection in captive wild-boars in Brazil.
24

Estudo etiológico e patológico de pneumonias em javalis criados de forma confinada no estado do Rio Grande do Sul / Etiological and pathological study of pneumonia in captive wild-boars in the state of Rio Grande do Sul

Biondo, Natalha January 2012 (has links)
As doenças respiratórias são muito comuns na produção intensiva de suínos, já em javalis são escassas informações sobre prevalência, etiologia e apresentação clínico-patológica destas enfermidades. No entanto, a presença de patógenos respiratórios comuns entre javalis selvagens e confinados e suínos domésticos já foi relatada. Este trabalho descreve as principais lesões macroscópicas e histológicas de pneumonias de javalis e os agentes comumente envolvidos. Foram examinados pulmões de javalis, ao abate, provenientes de criatórios comerciais e a principal lesão macroscópica foi consolidação crânio-ventral dos lobos craniais e médios e lesões crônicas cursando com hiperplasia linfóide na histologia. O principal agente bacteriano detectado foi o Mycoplasma hyopneumoniae (58,6%). Outros patógenos bacterianos detectados foram Actinobacillus pleuropneumoniae (48,8%), Haemophilus parasuis (49,6%), Mycoplasma hyorhinis (41,3%), Pasteurella multocida (9,1%) e Streptococcus suis (9,1%). Na segunda parte do trabalho, a pesquisa de patógenos virais foi direcionada para o Vírus da influenza suína (VIS) com objetivo de estudar o envolvimento em pneumonias de javalis de criatórios e a relação com agentes bacterianos encontrados. O vírus pandêmico A/H1N1/2009 foi detectado em 18,3% (11/60) e sua identidade foi confirmada por sequenciamento. A carga viral para H1N1 clássico variou de 4,58 a 6275 cópias/μL e para o H1N1 pandêmico, de 4,65 a 3863 cópias/μL. Nenhuma amostra apresentou título viral após a inoculação em ovos embrionados. As lesões histológicas principais foram broncopneumonia crônica difusa e pneumonia intersticial mononuclear leve, além de hiperplasia linfóide. As amostras positivas por RT-PCR para o VIS para o pH1N1 foram testadas por IHQ, sendo todas negativas para influenza A, mas todas eram positivas para M. hyopneumoniae. Quando testadas por bacteriologia, 18,2% das amostras foram positivas para P. multocida. O estudo mostrou que as pneumonias em javalis de criatório apresentaram lesões e patógenos associados similares aos encontrados em suínos domésticos ao abate. Este é o primeiro relato da infecção pelo vírus pH1N1 em javalis no Brasil. / Respiratory diseases are very common in swine intensive production, although in wild-boars the knowledge of the prevalence, etiology and clinic-pathological presentation of these diseases are very limited. However, the presence of common respiratory pathogens among wild-boar, captive wild-boar and domestic pigs has been reported. This paper describes the main macroscopic and histologic pneumonic lesions of captive wild-boars and pathogens commonly involved. Captive wild-boar lungs at slaughter were examined and the main macroscopic lesion observed was cranio-ventral consolidation of cranial and middle lobes and chronic lesions associated with lymphoid hyperplasia by histology. The main bacterial pathogen detected was Mycoplasma hyopneumoniae (58.6%). Other bacterial pathogens detected were Actinobacillus pleuropneumoniae (48.8%), Haemophilus parasuis (49.6%), Mycoplasma hyorhinis (41.3%), Pasteurella multocida (9.1%) and Streptococcus suis (9.1%). In the second part of this work, the survey of viral pathogens was directed to swine influenza virus (SIV) in order to study the involvement in captive wild-boar pneumonias and the relation with bacterial pathogens. The A/H1N1/2009 pandemic virus was detected in 18.3% (11/60) and its identity was confirmed by sequencing. The classical H1N1 viral load ranged from 4.58 to 6275 copies/uL and the pandemic H1N1, from 4.65 to 3863 copies/uL. No samples had viral titers after inoculation in embryonated eggs. The main histological lesions were chronic diffuse bronchopneumonia and interstitial mononuclear pneumonia as well as mild lymphoid hyperplasia. Samples positive to pH1N1 were assayed by IHC for SIV, all with negative results, and to M. hyopneumoniae, all were positive. When assayed by bacteriology, 18.2% of samples were positive to P. multocida. This study showed that pneumonia in captive wild-boar had similar lesions and associated pathogens were similar to those found in domestic pigs at slaughter. This is the first report of pH1N1 virus infection in captive wild-boars in Brazil.
25

Characterization of H1N2 variant influenza viruses in pigs

Duff, Michael Alan January 1900 (has links)
Master of Science / Department of Diagnostic Medicine/Pathobiology / Wenjun Ma / With introduction of the 2009 pandemic H1N1 virus (pH1N1) into swine herds, reassortment between the pH1N1 and endemic swine influenza viruses (SIVs) has been reported worldwide. Recently, reassortant H3N2 and H1N2 variant SIVs that contain the M gene from pH1N1 virus and the remaining seven genes from North American triple-reassortant (TR) SIVs have emerged. These variant viruses have caused more than 300 cases of human infections and one death in the USA, creating a major public health concern. To date, the pathogenicity and transmissibility of H1N2 variant viruses in pigs has not been investigated. Through passive surveillance, we have isolated two genotypes of reassortant H1N2 viruses with pH1N1 genes from diseased pigs in Kansas. Full genome sequence and phylogenetic analysis showed that one is a swine H1N2 variant virus (swH1N2v) with the M gene from pH1N1; the other is a reassortant H1N2 virus (2+6 rH1N2) with six internal genes from pH1N1 and the two surface genes from endemic North American TR H1N2 SIVs. Furthermore, we determined the pathogenicity and transmissibility of the swH1N2v, a human H1N2 variant (huH1N2v), and the 2+6 rH1N2 in pigs using an endemic TR H1N2 SIV (eH1N2) isolated in 2011 as a control. All four viruses were able to infect pigs and replicate in the lungs. Both H1N2 variant viruses caused more severe lung lesions in infected pigs when compared to the eH1N2 and 2+6 rH1N2 viruses. Although all four viruses are transmissible in pigs and were detected in the lungs of contact animals, the swH1N2v shed more efficiently than the other three viruses in the respective sentinel animals. The huH1N2v displayed delayed and inefficient nasal shedding in sentinel animals. Taken together, the human and swine H1N2 variant viruses are more pathogenic and the swH1N2v more transmissible in pigs and could pose a threat to public and animal health.
26

Caracterização genética de vírus influenza isolados em suínos no Rio Grande do Sul / Genetic characterization of influenza viruses recovered from pigs in Rio Grande do Sul

Schmidt, Candice January 2016 (has links)
O vírus influenza A (IAV) é um agente zoonótico de grande relevância tanto para saúde humana como animal. A influenza suína teve seu primeiro reconhecimento clínico em 1918, em suínos do Meio Oeste dos EUA, coincidindo com a pandemia de influenza em humanos. Desde então, o IAV permanece como um importante patógeno para a indústria suinícola em todo o mundo. A grande variabilidade genética destes vírus é causada por dois principais mecanismos genéticos: mutações pontuais e recombinações genéticas. A influenza é endêmica em muitos países e a emergências de recombinantes tem desafiado o controle e o diagnóstico desta enfermidade. No Brasil, a infecção pelo IAV em suínos (swIAV) não está bem caracterizada; poucos relatos evidenciam a prevalência deste agente antes do ano de 2009, especialmente no Estado do Rio Grande do Sul, que alberga um dos maiores rebanhos de suínos do Brasil. Em vista disso, este trabalho teve como objetivo investigar ocorrência de swIAV em alguns rebanhos suínos comerciais do Estado do Rio Grande do Sul, Brasil, no período de 2013-2014, e determinar os tipos e subtipos de vírus circulantes naquelas propriedades. O primeiro capítulo deste estudo reporta os aspectos clínicos, patológicos e virológicos da ocorrência de influenza suína e co-infecções identificadas em seis propriedades suinícolas selecionadas na região do Vale do Taquari. Neste estudo foram analisados suabes nasais coletados de 66 animais e 6 amostras de tecido pulmonar de suínos com sinais de infecção respiratória. A detecção viral foi feita através de uma PCR de triagem e confirmada através do isolamento viral em células MDCK. A identificação dos subtipos virais foi feita através de uma PCR em Tempo Real (rRT-PCR) para o subtipo A(H1N1)pdm09 ou através de uma PCR multiplex (RT-PCR) para outros subtipos de swIAV. A detecção de agentes bacterianos foi realizada apenas nas amostras de tecido pulmonar, através da pesquisa de genomas bacterianos por PCR. O subtipo A(H1N1)pdm09 foi identificado em 4/6 granjas e o subtipo H1N2 em 2/6 granjas. Além disso, agentes envolvidos no complexo respiratório dos suínos foram identificados em todas as granjas; Pasteurella multocida foi identificada em 5/6 granjas e Mycoplasma hyopneumoniae em 3/6 granjas. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) e PCV2 (1/6) também foram detectados. O segundo capítulo deste estudo teve como objetivo o sequenciamento do genoma completo de um novo recombinante H1N2 de origem humana, detectado em suínos. O genoma completo foi gerado através de uma RT-PCR. Os produtos foram purificados e submetidos ao sequenciamento utilizando a plataforma MiSeq (illumina). A análise filogenética revelou que as sequencias dos genes HA e NA correspondem a genes de IAV de origem humana, enquanto que as sequencias dos genes que codificam as proteínas internas do vírus (PB1, PB2, PA, NP, M e NS) correspondem a genes de amostras do vírus A(H1N1)pdm09. O terceiro capítulo reporta o sequenciamento completo dos genomas de 8 amostras de vírus influenza identificados nas populações de suínos amostradas. Foram identificados dois subtipos virais de origem humana (H1N2 e H3N2), além do vírus A(H1N1)pdm09. Os subtipos de origem humana possuem os genes HA e NA similares a vírus sazonais de humanos e os genes internos são estreitamente relacionados com o vírus A(H1N1)pdm09. / Influenza A virus (IAV) is a zoonotic agent of great relevance to human and animal health. Swine influenza was first recognized clinically in pigs in the Midwestern U.S., in 1918, coinciding with the human influenza pandemic. Since that time swine influenza has remained of importance to the swine industry throughout the world. The great genetic variability of influenza viruses is caused by two main genetic mechanisms: point mutations (antigenic drift) and gene reassortment (antigenic shift). Influenza is endemic in pigs in many countries and the emergence of new viruses has been challenging its control and diagnostics. Influenza virus (swIAV) infection in Brazilian swine population is not well characterized, and little evidence existed of swIAV circulation before 2009, especially in Rio Grande do Sul State, which hosts one of the largest swine populations in Brazil. Thus, this study aimed to investigate the occurrence of IAV in commercial swine herds in the state of Rio Grande do Sul, Brazil, between 2013-2014 and to know the types and subtypes of swine influenza viruses that are circulating in these herd. The first chapter of this study reports the clinical, pathological and virological aspects of the occurrence of swine influenza and related co-infections in six pig properties of the Taquari Valley region. In this study were analyzed nasal swabs collected from 66 animals and six lung tissue samples from pigs showing clinical signs of respiratory disease. IAV detection was performed by PCR screening and confirmed by virus isolation in MDCK cells and hemagglutination (HA). Influenza A subtyping was performed by real-time reverse transcription PCR (rRT-PCR) to detect the 2009 H1N1pandemic A(H1N1)pdm09; other swIAV subtypes were identifieded by multiplex RT-PCR. Bacterial infections were identified through detection of bacterial genomes by PCR, only in lung samples. Influenza A was detected by screening PCR in 46/66 swab samples and from 5/6 lungs. Virus was recovered from pigs of the six herds. Subtype A(H1N1)pdm09 was detected in 4/6 herds and H1N2 in the other 2/6 herds. In lung tissues, further agents involved in porcine respiratory disease complex were detected in all cases; Pasteurella multocida was identified in 5/6 samples and Mycoplasma hyopneumoniae in 3/6. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) and PCV2 (1/6) were also detected. The aim of the second chapter was to sequence the whole-genome of a novel human-like H1N2 swine influenza virus. Wholegenome sequences were generated by RT-PCR. Amplicons were purified followed by sequencing in the MiSeq sequencing platform (Illumina). Phylogenetic analyses revealed that the HA and NA genes clustered with influenza viruses of human lineage, whereas the internal genes (PB1, PB2, PA, NP, M and NS) clustered with the A(H1N1)pdm09. The third chapter reports the genetic sequencing of the full genomes of eight swine influenza viruses circulating in the sampled pig population. Two swine human-like subtypes (H1N2 and H3N2) and the A(H1N1)pdm09 virus were identified. The human-like subtypes have the HA and NA genes similar to the human seasonal strains and the internal genes are closely related to the virus A(H1N1)pdm09.
27

Caracterização genética de vírus influenza isolados em suínos no Rio Grande do Sul / Genetic characterization of influenza viruses recovered from pigs in Rio Grande do Sul

Schmidt, Candice January 2016 (has links)
O vírus influenza A (IAV) é um agente zoonótico de grande relevância tanto para saúde humana como animal. A influenza suína teve seu primeiro reconhecimento clínico em 1918, em suínos do Meio Oeste dos EUA, coincidindo com a pandemia de influenza em humanos. Desde então, o IAV permanece como um importante patógeno para a indústria suinícola em todo o mundo. A grande variabilidade genética destes vírus é causada por dois principais mecanismos genéticos: mutações pontuais e recombinações genéticas. A influenza é endêmica em muitos países e a emergências de recombinantes tem desafiado o controle e o diagnóstico desta enfermidade. No Brasil, a infecção pelo IAV em suínos (swIAV) não está bem caracterizada; poucos relatos evidenciam a prevalência deste agente antes do ano de 2009, especialmente no Estado do Rio Grande do Sul, que alberga um dos maiores rebanhos de suínos do Brasil. Em vista disso, este trabalho teve como objetivo investigar ocorrência de swIAV em alguns rebanhos suínos comerciais do Estado do Rio Grande do Sul, Brasil, no período de 2013-2014, e determinar os tipos e subtipos de vírus circulantes naquelas propriedades. O primeiro capítulo deste estudo reporta os aspectos clínicos, patológicos e virológicos da ocorrência de influenza suína e co-infecções identificadas em seis propriedades suinícolas selecionadas na região do Vale do Taquari. Neste estudo foram analisados suabes nasais coletados de 66 animais e 6 amostras de tecido pulmonar de suínos com sinais de infecção respiratória. A detecção viral foi feita através de uma PCR de triagem e confirmada através do isolamento viral em células MDCK. A identificação dos subtipos virais foi feita através de uma PCR em Tempo Real (rRT-PCR) para o subtipo A(H1N1)pdm09 ou através de uma PCR multiplex (RT-PCR) para outros subtipos de swIAV. A detecção de agentes bacterianos foi realizada apenas nas amostras de tecido pulmonar, através da pesquisa de genomas bacterianos por PCR. O subtipo A(H1N1)pdm09 foi identificado em 4/6 granjas e o subtipo H1N2 em 2/6 granjas. Além disso, agentes envolvidos no complexo respiratório dos suínos foram identificados em todas as granjas; Pasteurella multocida foi identificada em 5/6 granjas e Mycoplasma hyopneumoniae em 3/6 granjas. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) e PCV2 (1/6) também foram detectados. O segundo capítulo deste estudo teve como objetivo o sequenciamento do genoma completo de um novo recombinante H1N2 de origem humana, detectado em suínos. O genoma completo foi gerado através de uma RT-PCR. Os produtos foram purificados e submetidos ao sequenciamento utilizando a plataforma MiSeq (illumina). A análise filogenética revelou que as sequencias dos genes HA e NA correspondem a genes de IAV de origem humana, enquanto que as sequencias dos genes que codificam as proteínas internas do vírus (PB1, PB2, PA, NP, M e NS) correspondem a genes de amostras do vírus A(H1N1)pdm09. O terceiro capítulo reporta o sequenciamento completo dos genomas de 8 amostras de vírus influenza identificados nas populações de suínos amostradas. Foram identificados dois subtipos virais de origem humana (H1N2 e H3N2), além do vírus A(H1N1)pdm09. Os subtipos de origem humana possuem os genes HA e NA similares a vírus sazonais de humanos e os genes internos são estreitamente relacionados com o vírus A(H1N1)pdm09. / Influenza A virus (IAV) is a zoonotic agent of great relevance to human and animal health. Swine influenza was first recognized clinically in pigs in the Midwestern U.S., in 1918, coinciding with the human influenza pandemic. Since that time swine influenza has remained of importance to the swine industry throughout the world. The great genetic variability of influenza viruses is caused by two main genetic mechanisms: point mutations (antigenic drift) and gene reassortment (antigenic shift). Influenza is endemic in pigs in many countries and the emergence of new viruses has been challenging its control and diagnostics. Influenza virus (swIAV) infection in Brazilian swine population is not well characterized, and little evidence existed of swIAV circulation before 2009, especially in Rio Grande do Sul State, which hosts one of the largest swine populations in Brazil. Thus, this study aimed to investigate the occurrence of IAV in commercial swine herds in the state of Rio Grande do Sul, Brazil, between 2013-2014 and to know the types and subtypes of swine influenza viruses that are circulating in these herd. The first chapter of this study reports the clinical, pathological and virological aspects of the occurrence of swine influenza and related co-infections in six pig properties of the Taquari Valley region. In this study were analyzed nasal swabs collected from 66 animals and six lung tissue samples from pigs showing clinical signs of respiratory disease. IAV detection was performed by PCR screening and confirmed by virus isolation in MDCK cells and hemagglutination (HA). Influenza A subtyping was performed by real-time reverse transcription PCR (rRT-PCR) to detect the 2009 H1N1pandemic A(H1N1)pdm09; other swIAV subtypes were identifieded by multiplex RT-PCR. Bacterial infections were identified through detection of bacterial genomes by PCR, only in lung samples. Influenza A was detected by screening PCR in 46/66 swab samples and from 5/6 lungs. Virus was recovered from pigs of the six herds. Subtype A(H1N1)pdm09 was detected in 4/6 herds and H1N2 in the other 2/6 herds. In lung tissues, further agents involved in porcine respiratory disease complex were detected in all cases; Pasteurella multocida was identified in 5/6 samples and Mycoplasma hyopneumoniae in 3/6. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) and PCV2 (1/6) were also detected. The aim of the second chapter was to sequence the whole-genome of a novel human-like H1N2 swine influenza virus. Wholegenome sequences were generated by RT-PCR. Amplicons were purified followed by sequencing in the MiSeq sequencing platform (Illumina). Phylogenetic analyses revealed that the HA and NA genes clustered with influenza viruses of human lineage, whereas the internal genes (PB1, PB2, PA, NP, M and NS) clustered with the A(H1N1)pdm09. The third chapter reports the genetic sequencing of the full genomes of eight swine influenza viruses circulating in the sampled pig population. Two swine human-like subtypes (H1N2 and H3N2) and the A(H1N1)pdm09 virus were identified. The human-like subtypes have the HA and NA genes similar to the human seasonal strains and the internal genes are closely related to the virus A(H1N1)pdm09.
28

Caracterização genética de vírus influenza isolados em suínos no Rio Grande do Sul / Genetic characterization of influenza viruses recovered from pigs in Rio Grande do Sul

Schmidt, Candice January 2016 (has links)
O vírus influenza A (IAV) é um agente zoonótico de grande relevância tanto para saúde humana como animal. A influenza suína teve seu primeiro reconhecimento clínico em 1918, em suínos do Meio Oeste dos EUA, coincidindo com a pandemia de influenza em humanos. Desde então, o IAV permanece como um importante patógeno para a indústria suinícola em todo o mundo. A grande variabilidade genética destes vírus é causada por dois principais mecanismos genéticos: mutações pontuais e recombinações genéticas. A influenza é endêmica em muitos países e a emergências de recombinantes tem desafiado o controle e o diagnóstico desta enfermidade. No Brasil, a infecção pelo IAV em suínos (swIAV) não está bem caracterizada; poucos relatos evidenciam a prevalência deste agente antes do ano de 2009, especialmente no Estado do Rio Grande do Sul, que alberga um dos maiores rebanhos de suínos do Brasil. Em vista disso, este trabalho teve como objetivo investigar ocorrência de swIAV em alguns rebanhos suínos comerciais do Estado do Rio Grande do Sul, Brasil, no período de 2013-2014, e determinar os tipos e subtipos de vírus circulantes naquelas propriedades. O primeiro capítulo deste estudo reporta os aspectos clínicos, patológicos e virológicos da ocorrência de influenza suína e co-infecções identificadas em seis propriedades suinícolas selecionadas na região do Vale do Taquari. Neste estudo foram analisados suabes nasais coletados de 66 animais e 6 amostras de tecido pulmonar de suínos com sinais de infecção respiratória. A detecção viral foi feita através de uma PCR de triagem e confirmada através do isolamento viral em células MDCK. A identificação dos subtipos virais foi feita através de uma PCR em Tempo Real (rRT-PCR) para o subtipo A(H1N1)pdm09 ou através de uma PCR multiplex (RT-PCR) para outros subtipos de swIAV. A detecção de agentes bacterianos foi realizada apenas nas amostras de tecido pulmonar, através da pesquisa de genomas bacterianos por PCR. O subtipo A(H1N1)pdm09 foi identificado em 4/6 granjas e o subtipo H1N2 em 2/6 granjas. Além disso, agentes envolvidos no complexo respiratório dos suínos foram identificados em todas as granjas; Pasteurella multocida foi identificada em 5/6 granjas e Mycoplasma hyopneumoniae em 3/6 granjas. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) e PCV2 (1/6) também foram detectados. O segundo capítulo deste estudo teve como objetivo o sequenciamento do genoma completo de um novo recombinante H1N2 de origem humana, detectado em suínos. O genoma completo foi gerado através de uma RT-PCR. Os produtos foram purificados e submetidos ao sequenciamento utilizando a plataforma MiSeq (illumina). A análise filogenética revelou que as sequencias dos genes HA e NA correspondem a genes de IAV de origem humana, enquanto que as sequencias dos genes que codificam as proteínas internas do vírus (PB1, PB2, PA, NP, M e NS) correspondem a genes de amostras do vírus A(H1N1)pdm09. O terceiro capítulo reporta o sequenciamento completo dos genomas de 8 amostras de vírus influenza identificados nas populações de suínos amostradas. Foram identificados dois subtipos virais de origem humana (H1N2 e H3N2), além do vírus A(H1N1)pdm09. Os subtipos de origem humana possuem os genes HA e NA similares a vírus sazonais de humanos e os genes internos são estreitamente relacionados com o vírus A(H1N1)pdm09. / Influenza A virus (IAV) is a zoonotic agent of great relevance to human and animal health. Swine influenza was first recognized clinically in pigs in the Midwestern U.S., in 1918, coinciding with the human influenza pandemic. Since that time swine influenza has remained of importance to the swine industry throughout the world. The great genetic variability of influenza viruses is caused by two main genetic mechanisms: point mutations (antigenic drift) and gene reassortment (antigenic shift). Influenza is endemic in pigs in many countries and the emergence of new viruses has been challenging its control and diagnostics. Influenza virus (swIAV) infection in Brazilian swine population is not well characterized, and little evidence existed of swIAV circulation before 2009, especially in Rio Grande do Sul State, which hosts one of the largest swine populations in Brazil. Thus, this study aimed to investigate the occurrence of IAV in commercial swine herds in the state of Rio Grande do Sul, Brazil, between 2013-2014 and to know the types and subtypes of swine influenza viruses that are circulating in these herd. The first chapter of this study reports the clinical, pathological and virological aspects of the occurrence of swine influenza and related co-infections in six pig properties of the Taquari Valley region. In this study were analyzed nasal swabs collected from 66 animals and six lung tissue samples from pigs showing clinical signs of respiratory disease. IAV detection was performed by PCR screening and confirmed by virus isolation in MDCK cells and hemagglutination (HA). Influenza A subtyping was performed by real-time reverse transcription PCR (rRT-PCR) to detect the 2009 H1N1pandemic A(H1N1)pdm09; other swIAV subtypes were identifieded by multiplex RT-PCR. Bacterial infections were identified through detection of bacterial genomes by PCR, only in lung samples. Influenza A was detected by screening PCR in 46/66 swab samples and from 5/6 lungs. Virus was recovered from pigs of the six herds. Subtype A(H1N1)pdm09 was detected in 4/6 herds and H1N2 in the other 2/6 herds. In lung tissues, further agents involved in porcine respiratory disease complex were detected in all cases; Pasteurella multocida was identified in 5/6 samples and Mycoplasma hyopneumoniae in 3/6. Actinobacillus pleuropneumoniae (1/6), Haemophilus parasuis (1/6) and PCV2 (1/6) were also detected. The aim of the second chapter was to sequence the whole-genome of a novel human-like H1N2 swine influenza virus. Wholegenome sequences were generated by RT-PCR. Amplicons were purified followed by sequencing in the MiSeq sequencing platform (Illumina). Phylogenetic analyses revealed that the HA and NA genes clustered with influenza viruses of human lineage, whereas the internal genes (PB1, PB2, PA, NP, M and NS) clustered with the A(H1N1)pdm09. The third chapter reports the genetic sequencing of the full genomes of eight swine influenza viruses circulating in the sampled pig population. Two swine human-like subtypes (H1N2 and H3N2) and the A(H1N1)pdm09 virus were identified. The human-like subtypes have the HA and NA genes similar to the human seasonal strains and the internal genes are closely related to the virus A(H1N1)pdm09.
29

Development and Evaluation of Nanoparticle-based Intranasal Inactivated Influenza Virus Vaccine Candidates in Pigs

Dhakal, Santosh 21 December 2018 (has links)
No description available.
30

Odjectifying a health crisis: risk exemplar, news making and social risks = 健康危機的客觀化 : 風險範例、新聞建構、與社會風險. / 健康危機的客觀化 : 風險範例、新聞建構、與社會風險 / Odjectifying a health crisis: risk exemplar, news making and social risks = Jian kang wei ji de ke guan hua : feng xian fan li, xin wen jian gou, yu she hui feng xian. / Jian kang wei ji de ke guan hua: feng xian fan li, xin wen jian gou, yu she hui feng xian

January 2014 (has links)
我們身處於一個充滿風險的社會。金融海嘯、核能危機、全球暖化、食品問題等,在說明社會步向現代化的後遺症,正如何為人類帶來更難預測的風險,並無孔不入般影響我們的日常生活(Beck, 1992)。在這理論基礎上,本文將探究新聞製作於建構風險的角色,並提出一個名為「客觀化」(objectification) 的過程---新聞媒體如何在科學專家的意見眾說紛紜、對風險難有最終定案之下,把有關社會風險的新聞論述詮釋為客觀的社會事實。我尤其探討風險範例的建構---一些有關風險的新聞事件其後演變為重要範例,並影響日後類似事件的新聞論述。 / 為求以實證方法探究風險「合理化」的過程,我將以香港(中華人民共和國的特別行政區) 的新聞論述如何回應2009年全球豬流感危機作為案例。豬流感是香港經歷2003年非典型肺炎危機(又稱「沙士」) 的重創後,首次面對的全球疫症危機。香港新聞如何呈現豬流感疫情,亦深受「沙士」時的歷史回憶、經驗及後遺所影響。故此,這案例有助我研究風險範例於風險「合理化」時的作用。我從香港報章隨機抽樣出有關豬流感的新聞論述的樣本,並透過內容分析和文本分析,研究香港新聞如何敍述豬流感危機,以及相關敍述所包含的意識形態。我亦走訪了當年採訪豬流感新聞的新聞工作者、有份向傳媒提供專家意見的醫學專家、以及負責制定香港政府防控豬流感政策的官員,以了解建構豬流感風險背後的社會互動。 / 本文的研究顯示,香港有關豬流感危機的新聞論述,是如何奠基於「沙士」這風險範例而建構。豬流感起來襲初時,新聞論述廣泛地藉「沙士」的經驗去詮釋豬流感可能帶給香港的後果。新聞工作者於「沙士」時的採訪經歷,亦成為他們報道豬流感新聞時尋找醫學專家意見的參照經驗,尤其是當醫學專家意見紛紜、新聞工作者要判斷誰人的意見較有權威去界定健康風險之時。本文主要闡述新聞的建構於社會回應風險時所起的關鍵作用,從而帶出這於風險社會理論、以及當我們探究新聞媒體及傳播於現代風險社會的角色時,仍未受足夠重視的重要層面。 / We are witnessing the formation of a risk society, with financial instability, nuclear catastrophes, global warming, and food crises, and just to give a few examples, becoming parts of our everyday life in an age of risk characterized by uncertainties stemming from system failure of modernization (Beck, 1992). In the light of this theoretical concern, in this study I shall scrutinize how news making plays its role in the construction of risk. This, I suggest, is a process of risk objectification ---how news media justifies its discourse of social risk by making social facts upon uncertainties and inconclusive scientific opinions. Specifically, I shall focus on the creation of risk exemplar. That is, some news events become critical exemplar that would shape the news construction of subsequent crises of similar sources. / To look into the process of risk objectification empirically, I shall examine what were the main features of the news discourse in Hong Kong, a Special Administrative Region of China, in reaction to the global health crisis of Swine Flu in 2009. Swine Flu was the first pandemic crisis encountered by Hong Kong after its devastating suffering from the epidemic of Severe Acute Respiratory Syndrome (SARS) in 2003. The news representation of Swine Flu was influenced by the historical memory, experience and legacies of SARS and this helps illustrate how risk exemplar contributes to risk legitimization. I carried out content and textual analysis respectively on a random sample of Hong Kong’s newspapers for the purpose of analyzing the key narrations of Swine Flu and the underlying ideological packages of such narrations. I also conducted in-depth interviews with journalists, medical experts and public officials who were deeply involved in the news making of Swine Flu so as to uncover the social dynamics in the process of risk construction. / Key findings of this thesis highlight how the health crisis of Swine Flu was staged by the risk exemplar of SARS. Experience of SARS was widely drawn upon for making sense of the potential impacts of Swine Flu when it first broke out. It was also the key reference for journalists when seeking expert advices, particularly when identifying those who are more authoritative among different opinions in defining the nature of the risk. It is my argument that news making plays a critical role in the shaping of the social reactions to a risk. My analysis thus adds an important, but somehow unduly neglected, dimension to theory of risk society and our understanding of the role of news media and communication in contemporary risk society. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chan, Chi Kit. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 240-250). / Abstracts also in Chinese. / Chan, Chi Kit.

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