• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 19
  • 12
  • 2
  • 1
  • 1
  • Tagged with
  • 40
  • 26
  • 15
  • 14
  • 14
  • 13
  • 10
  • 9
  • 8
  • 8
  • 8
  • 7
  • 7
  • 6
  • 6
  • 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.
11

Multiplex reverse transcription-PCR for detection and identification of human parainfluenza viruses 1,2,3 and 4 infection in hospitalized children with respiratory disease in Hong Kong /

Lam, Siu-yan, January 2007 (has links)
Thesis (M. Med. Sc.)--University of Hong Kong, 2007.
12

Perfil clínico-epidemiológico das infecções respiratórias agudas causadas por vírus parainfluenza em crianças atendidas em um hospital de referência da cidade de Fortaleza–CE / Clinical and epidemiological profile of the acute respiratory infections caused by parainfluenza virus in children attended at a major pediatric hospital in Fortaleza–CE

Fé, Mariana Mota Moura January 2007 (has links)
FÉ, Mariana Mota Moura. Perfil clínico-epidemiológico das infecções respiratórias agudas causadas por vírus parainfluenza em crianças atendidas em um hospital de referência da cidade de Fortaleza-CE. 2007. 139 f. Dissertação (Mestrado em Microbiologia Médica) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2007. / Submitted by denise santos (denise.santos@ufc.br) on 2012-01-05T13:51:47Z No. of bitstreams: 1 2007_dis_mmmfe.pdf: 1257125 bytes, checksum: f99c4398d4f75d5e46570bfa14f1756e (MD5) / Approved for entry into archive by Eliene Nascimento(elienegvn@hotmail.com) on 2012-02-02T16:30:16Z (GMT) No. of bitstreams: 1 2007_dis_mmmfe.pdf: 1257125 bytes, checksum: f99c4398d4f75d5e46570bfa14f1756e (MD5) / Made available in DSpace on 2012-02-02T16:30:16Z (GMT). No. of bitstreams: 1 2007_dis_mmmfe.pdf: 1257125 bytes, checksum: f99c4398d4f75d5e46570bfa14f1756e (MD5) Previous issue date: 2007 / Acute respiratory infections (ARI) are an important public health problem throughout the world and parainfluenza viruses are among the major etiologic agents. The objectives of this study were: a) to determine the frequency of parainfluenza infections among children attending Hospital Infantil Albert Sabin, a major pediatric hospital in Fortaleza - CE, from January 2001 to December 2006; b) to describe the seasonal pattern and the clinical and epidemiological characteristics of these infections; and c) to compare clinical and epidemiological characteristics of parainfluenza infections and infections caused by other respiratory viruses. Nasopharyngeal aspirates from children with acute respiratory symptoms were collected and submitted to indirect immunofluorescence assays to detect human parainfluenza virus 1, 2 and 3 (HPIV-1, 2 and 3), respiratory syncytial virus (RSV), influenza A and B and adenovirus. During the six-year study period, samples were collected from 3,070 generally healthy children and respiratory viruses were demonstrated in 933 cases (30.39%), of which 117 were positive for parainfluenza virus (3.81%). HPIV-3 was the most frequently detected type of parainfluenza virus accounting for 83.76% of cases, followed by HPIV-1 (11.96%) and HPIV-2 (4.27%). HPIV-3 infections were seasonal with most cases observed from September to November. Although the total number of ARIs was directly associated with the time of the rainy season, HPIV-3 infections were inversely related with rainfall indices. Most HPIV-3 infections were seen in outpatients. The mean age of patients infected by HPIV-3 was 20 months, which is significantly younger than for influenza A (mean age: 34 months) and significantly older than for RSV (mean age: 15 months). HPIV-3 patients presented significantly lower indices of dyspnea, cough, crackles, chest retractions and radiologic abnormalities than RSV patients. Upper airway infection was the most frequent clinical syndrome among HPIV-3 patients. HPIV-3 patients needed less oxygen, salbutamol, antibiotics, corticosteroids and nebulization than RSV patients. In contrast with earlier observations for Northeastern Brazil, our results demonstrate a seasonal pattern for the occurrence of HPIV-3 infections with most cases observed during the dry season. The results also suggest that infections caused by HPIV-3 are milder than infections caused by RSV in previously healthy children. / As infecções respiratórias agudas (IRAs) são um importante problema de saúde pública em todo o mundo, e os vírus parainfluenza estão entre os seus agentes mais freqüentes. Este estudo teve como objetivos: determinar a freqüência de IRAs pelo vírus parainfluenza entre crianças atendidas no Hospital Infantil Albert Sabin, hospital pediátrico de referência da cidade de Fortaleza – CE, de janeiro de 2001 a dezembro de 2006; descrever o padrão de sazonalidade e as características clínico-epidemiológicas destas infecções; e comparar as características clínico-epidemiológicas das infecções por parainfluenza com as das IRAs causadas por outros vírus. Foram coletados aspirados de nasofaringe de crianças com sintomas de IRAs, e foi utilizada a imunofluorescência indireta para a detecção dos vírus: parainfluenza humano 1, 2 e 3 (VPIH-1, 2 e 3), vírus sincicial respiratório (VSR), influenza A e B e adenovírus. Nos seis anos de estudo, foram colhidas amostras de 3070 crianças, a maioria delas previamente sadias, com a detecção de vírus respiratórios em 933 (30,39%), e dos vírus parainfluenza em 117 casos (3,81% do total). Dentre os casos de parainfluenza, o VPIH-3 foi o tipo mais freqüente (83,76% dos casos), com menor detecção do VPIH-1 (11,96%) e do VPIH-2 (4,27%). A infecção pelo VPIH-3 apresentou comportamento sazonal, com maior detecção nos meses de setembro a novembro. Embora o total de casos de IRAs tenha apresentado relação direta com os índices pluviométricos, o número de casos de VPIH-3 apresentou relação inversa com a pluviometria, sendo maior nos meses secos. A maioria dos pacientes positivos para parainfluenza foi atendida na emergência ou nos ambulatórios. A média de idades das crianças com infecção pelo VPIH-3 foi de 20 meses, sendo significativamente menor que a das crianças infectadas pelo vírus influenza A (34 meses), e maior que a das infectadas pelo VSR (15 meses). Os pacientes positivos para o VPIH-3 apresentaram significativamente menos dispnéia, tosse, estertores, tiragem intercostal e alterações radiológicas que os positivos para VSR. As infecções de vias aéreas superiores constituíram a síndrome clínica mais freqüente entre os casos de VPIH-3. Os pacientes positivos para VPIH-3 necessitaram menos de terapia com antibióticos, corticóides, oxigênio, nebulização e/ou salbutamol que os positivos para VSR. Os resultados demonstraram um comportamento sazonal do VPIH-3, relacionado aos meses secos, o que não tinha sido relatado previamente no Nordeste brasileiro, além de apontarem para uma menor gravidade das infecções causadas pelo VPIH-3, na comparação com o VSR, em crianças previamente sadias.
13

Infection and immunoregulation of T lymphocytes by parainfluenza virus type 3

Sieg, Scott F. January 1996 (has links)
No description available.
14

Epidemiologia e caracterização molecular do Vírus Parainfluenza Humano 1, 2 e 3 em crianças menores de 5 anos de idade atendidas no Hospital Universitário em 2007, São Paulo - Brasil. / Molecular characterization and epidemiology of Human Parainfluenza Vírus isoled from children below five years old hospitalized at the University Hospital, USP, in 2007, São Paulo - Brazil.

Amaral, Larissa Morais Bomilcar do 09 November 2009 (has links)
O objetivo do presente trabalho é descrever o perfil epidemiológico e molecular dos vírus Parainfluenza em crianças menores de 5 ano de idade, com infecção das vias respiratórias. Por tanto, aspirados de nasofaringe de 742 crianças foram examinadas para os Vírus Parainfluenza Humano(HPIV1, HPIV2 e HPIV3), hRSV, hMPV e IA e IB pela técnica de RT-PCR, durante o ano de 2007. Ao todo foram identificados 52(7%) Parainfluenza vírus, sendo 9(17,3%) HPIV1, 8(15,4%) HPIV2 e 35(67,3%) HPIV3. Destas, 12 (23%) foram casos de coinfecções, sendo 3 (25%) de HPIV3 com VRS, 3 (25%) com MPV e 3 (25%) com HPIV1 e 1(8,33%) com HPIV2; além de 1(8,33%) do HPIV1 com hVSR; e 1(8,33%) de HPIV2 com o hMPV. Com relação ao setor de atendimento, dos 52 pacientes com HPIV, 8(5%) dos casos foram atendidos no PA; 38(8,4%) na ENF; 6(18,2%) na UTI. Obtivemos, no estudo, 21(5,3%) crianças do sexo masculino com infecção por HPIV e 31(9%) de sexo feminino. Quanto a idade, as crianças entre 1 a 23 meses foram as mais frequentemente infectadas. Com relação ao diagnóstico clínico tivemos 19(36,5%) casos com bronquiolites, 13(25%) casos com pneumonia, 7(13,4%) com broncopneumonia, 2(3,9%) de casos de dispnéia e 2(3,9%) de IVAS, além de 9(17,3%) sem informação da sintomatologia. A sazonalidade do HPIV foi marcada pela circulação do HPIV3 durante o ano inteiro, com maior incidência em outubro(primavera). O HPIV 1 e 2 se alternaram durante o ano, onde o HPIV1 circulou no primeiro semestre com maior incidência no mês de abril e maio e o HPIV2 circulou no segundo semestre com maior incidência em outubro, coincidindo com o HPIV3. O Estudo filogenético dos HPIV1 demonstrou 9 mutações nucleotídicas, sendo que 4 são características das amostras brasileiras. Entretanto, quando feito a transdução para aminoácido, apenas uma mutação foi não silenciosa, onde observamos a mudança de glicina, nas amostras do Genbank, para argenina, nas amostras brasileiras, deixando-as em um clado único na topologia da árvore obtida. O HPIV3 apresentou 4 subgrupos distintos durante o ano e suas mutações tanto nucleotídicas quanto de aminoácidos foram todas silenciosas. Em conclusão o vírus parainfluenza representaram a 3ª maior causa de infecção das vias respiratórias inferiores, precedido pelo vírus respiratório Sincicial e o Metapneumovirus. / The goal of the present work was to characterize the epidemiologic and molecular profile of the parainfluenza virus in children with less than 5 years of age and presenting respiratory tract infection. Human Parainfluenza (HPIV1, HPIV2, HPIV3), and hRSV, hMPV e IA e IB were evaluated in nasopharyngeal aspirate from 742 children by RT-PCR during the year of 2007. Human parainfluenza was identified in 52(7%) of the samples, which include 9(17,3%) HPIV1, 8(15,4%) HPIV2 and 35(67,3%) HPIV3 17,3% (n=9). Among the 52 cases with parainfluenza, 12 (23%) presented coinfection with other viruses: 3 (25%) coinfection with HPIV3 and VRS, 3 (25%) MPV , 3 (25%) HPIV1 , 1(8,33%) HPIV2 . In addition, it was observed 1(8,33%) of cases with HPIV1 and hVSR; and 1(8,33%) of cases with HPIV2 and hMPV. With respect to the clinical care of the 52 patients with HPIV, 8(5%) were treated at the ER? ; 38(8,4%) at the ENF and 6(18,2%) at the ICU. With respect to gender, a total of 21(5,3%) of the participants with HPIV infections were male and 31(9%) were female. The prevalent age range of participants with infections was 1-23 months of age. The following clinical parameters were observed: bronchiolitis 19(36,5%), pneumonia 13(25%), bronchopneumonia 7(13,4%), dyspnea 2(3,9%) and IVAS 2(3,9%). No clinical information was available for 9(17,3%) cases. HPIV3 infections were detected all year long with an incidence peak in October (Spring). HPIV1 and 2 infections were intercalated during the year. HPIV1 was detected during the first semester with peaks of incidence in April and May whereas HPIV2 was detected during the second semester with peaks of incidence in October, coexisting with HPIV3. HPIV1phylogenetic studies revealed 9 genetic mutations. 4 out of the 9 mutations are exclusively found in the brazilian population. However, only one of these 9 mutations is non-silent and causes a glycine to argenine substitution. When compared to other brazilian sequences in the GenBank, this observation revealed um clado único na topologia da árvore obtida. HPIV3 genotyping included 4 distinct groups detected all year long. All mutations observed in HPIV3 were silent. In conclusion, the parainfluenza virus represent the 3rd major cause of infection of the lower respiratory tract, following the sincicial respiratory virus and the Metapneumovirus.
15

Perfil clÃnico-epidemiolÃgico das infecÃÃes respiratÃrias agudas causadas por vÃrus parainfluenza em crianÃas atendidas em um hospital de referÃncia da cidade de Fortaleza â CE / Clinical and epidemiological profile of the acute respiratory infections caused by parainfluenza virus in children attended at a major pediatric hospital in Fortaleza â CE

Mariana Mota Moura FÃ 21 March 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As infecÃÃes respiratÃrias agudas (IRAs) sÃo um importante problema de saÃde pÃblica em todo o mundo, e os vÃrus parainfluenza estÃo entre os seus agentes mais freqÃentes. Este estudo teve como objetivos: determinar a freqÃÃncia de IRAs pelo vÃrus parainfluenza entre crianÃas atendidas no Hospital Infantil Albert Sabin, hospital pediÃtrico de referÃncia da cidade de Fortaleza â CE, de janeiro de 2001 a dezembro de 2006; descrever o padrÃo de sazonalidade e as caracterÃsticas clÃnico-epidemiolÃgicas destas infecÃÃes; e comparar as caracterÃsticas clÃnico-epidemiolÃgicas das infecÃÃes por parainfluenza com as das IRAs causadas por outros vÃrus. Foram coletados aspirados de nasofaringe de crianÃas com sintomas de IRAs, e foi utilizada a imunofluorescÃncia indireta para a detecÃÃo dos vÃrus: parainfluenza humano 1, 2 e 3 (VPIH-1, 2 e 3), vÃrus sincicial respiratÃrio (VSR), influenza A e B e adenovÃrus. Nos seis anos de estudo, foram colhidas amostras de 3070 crianÃas, a maioria delas previamente sadias, com a detecÃÃo de vÃrus respiratÃrios em 933 (30,39%), e dos vÃrus parainfluenza em 117 casos (3,81% do total). Dentre os casos de parainfluenza, o VPIH-3 foi o tipo mais freqÃente (83,76% dos casos), com menor detecÃÃo do VPIH-1 (11,96%) e do VPIH-2 (4,27%). A infecÃÃo pelo VPIH-3 apresentou comportamento sazonal, com maior detecÃÃo nos meses de setembro a novembro. Embora o total de casos de IRAs tenha apresentado relaÃÃo direta com os Ãndices pluviomÃtricos, o nÃmero de casos de VPIH-3 apresentou relaÃÃo inversa com a pluviometria, sendo maior nos meses secos. A maioria dos pacientes positivos para parainfluenza foi atendida na emergÃncia ou nos ambulatÃrios. A mÃdia de idades das crianÃas com infecÃÃo pelo VPIH-3 foi de 20 meses, sendo significativamente menor que a das crianÃas infectadas pelo vÃrus influenza A (34 meses), e maior que a das infectadas pelo VSR (15 meses). Os pacientes positivos para o VPIH-3 apresentaram significativamente menos dispnÃia, tosse, estertores, tiragem intercostal e alteraÃÃes radiolÃgicas que os positivos para VSR. As infecÃÃes de vias aÃreas superiores constituÃram a sÃndrome clÃnica mais freqÃente entre os casos de VPIH-3. Os pacientes positivos para VPIH-3 necessitaram menos de terapia com antibiÃticos, corticÃides, oxigÃnio, nebulizaÃÃo e/ou salbutamol que os positivos para VSR. Os resultados demonstraram um comportamento sazonal do VPIH-3, relacionado aos meses secos, o que nÃo tinha sido relatado previamente no Nordeste brasileiro, alÃm de apontarem para uma menor gravidade das infecÃÃes causadas pelo VPIH-3, na comparaÃÃo com o VSR, em crianÃas previamente sadias / Acute respiratory infections (ARI) are an important public health problem throughout the world and parainfluenza viruses are among the major etiologic agents. The objectives of this study were: a) to determine the frequency of parainfluenza infections among children attending Hospital Infantil Albert Sabin, a major pediatric hospital in Fortaleza - CE, from January 2001 to December 2006; b) to describe the seasonal pattern and the clinical and epidemiological characteristics of these infections; and c) to compare clinical and epidemiological characteristics of parainfluenza infections and infections caused by other respiratory viruses. Nasopharyngeal aspirates from children with acute respiratory symptoms were collected and submitted to indirect immunofluorescence assays to detect human parainfluenza virus 1, 2 and 3 (HPIV-1, 2 and 3), respiratory syncytial virus (RSV), influenza A and B and adenovirus. During the six-year study period, samples were collected from 3,070 generally healthy children and respiratory viruses were demonstrated in 933 cases (30.39%), of which 117 were positive for parainfluenza virus (3.81%). HPIV-3 was the most frequently detected type of parainfluenza virus accounting for 83.76% of cases, followed by HPIV-1 (11.96%) and HPIV-2 (4.27%). HPIV-3 infections were seasonal with most cases observed from September to November. Although the total number of ARIs was directly associated with the time of the rainy season, HPIV-3 infections were inversely related with rainfall indices. Most HPIV-3 infections were seen in outpatients. The mean age of patients infected by HPIV-3 was 20 months, which is significantly younger than for influenza A (mean age: 34 months) and significantly older than for RSV (mean age: 15 months). HPIV-3 patients presented significantly lower indices of dyspnea, cough, crackles, chest retractions and radiologic abnormalities than RSV patients. Upper airway infection was the most frequent clinical syndrome among HPIV-3 patients. HPIV-3 patients needed less oxygen, salbutamol, antibiotics, corticosteroids and nebulization than RSV patients. In contrast with earlier observations for Northeastern Brazil, our results demonstrate a seasonal pattern for the occurrence of HPIV-3 infections with most cases observed during the dry season. The results also suggest that infections caused by HPIV-3 are milder than infections caused by RSV in previously healthy children
16

Epidemiologia e caracterização molecular do Vírus Parainfluenza Humano 1, 2 e 3 em crianças menores de 5 anos de idade atendidas no Hospital Universitário em 2007, São Paulo - Brasil. / Molecular characterization and epidemiology of Human Parainfluenza Vírus isoled from children below five years old hospitalized at the University Hospital, USP, in 2007, São Paulo - Brazil.

Larissa Morais Bomilcar do Amaral 09 November 2009 (has links)
O objetivo do presente trabalho é descrever o perfil epidemiológico e molecular dos vírus Parainfluenza em crianças menores de 5 ano de idade, com infecção das vias respiratórias. Por tanto, aspirados de nasofaringe de 742 crianças foram examinadas para os Vírus Parainfluenza Humano(HPIV1, HPIV2 e HPIV3), hRSV, hMPV e IA e IB pela técnica de RT-PCR, durante o ano de 2007. Ao todo foram identificados 52(7%) Parainfluenza vírus, sendo 9(17,3%) HPIV1, 8(15,4%) HPIV2 e 35(67,3%) HPIV3. Destas, 12 (23%) foram casos de coinfecções, sendo 3 (25%) de HPIV3 com VRS, 3 (25%) com MPV e 3 (25%) com HPIV1 e 1(8,33%) com HPIV2; além de 1(8,33%) do HPIV1 com hVSR; e 1(8,33%) de HPIV2 com o hMPV. Com relação ao setor de atendimento, dos 52 pacientes com HPIV, 8(5%) dos casos foram atendidos no PA; 38(8,4%) na ENF; 6(18,2%) na UTI. Obtivemos, no estudo, 21(5,3%) crianças do sexo masculino com infecção por HPIV e 31(9%) de sexo feminino. Quanto a idade, as crianças entre 1 a 23 meses foram as mais frequentemente infectadas. Com relação ao diagnóstico clínico tivemos 19(36,5%) casos com bronquiolites, 13(25%) casos com pneumonia, 7(13,4%) com broncopneumonia, 2(3,9%) de casos de dispnéia e 2(3,9%) de IVAS, além de 9(17,3%) sem informação da sintomatologia. A sazonalidade do HPIV foi marcada pela circulação do HPIV3 durante o ano inteiro, com maior incidência em outubro(primavera). O HPIV 1 e 2 se alternaram durante o ano, onde o HPIV1 circulou no primeiro semestre com maior incidência no mês de abril e maio e o HPIV2 circulou no segundo semestre com maior incidência em outubro, coincidindo com o HPIV3. O Estudo filogenético dos HPIV1 demonstrou 9 mutações nucleotídicas, sendo que 4 são características das amostras brasileiras. Entretanto, quando feito a transdução para aminoácido, apenas uma mutação foi não silenciosa, onde observamos a mudança de glicina, nas amostras do Genbank, para argenina, nas amostras brasileiras, deixando-as em um clado único na topologia da árvore obtida. O HPIV3 apresentou 4 subgrupos distintos durante o ano e suas mutações tanto nucleotídicas quanto de aminoácidos foram todas silenciosas. Em conclusão o vírus parainfluenza representaram a 3ª maior causa de infecção das vias respiratórias inferiores, precedido pelo vírus respiratório Sincicial e o Metapneumovirus. / The goal of the present work was to characterize the epidemiologic and molecular profile of the parainfluenza virus in children with less than 5 years of age and presenting respiratory tract infection. Human Parainfluenza (HPIV1, HPIV2, HPIV3), and hRSV, hMPV e IA e IB were evaluated in nasopharyngeal aspirate from 742 children by RT-PCR during the year of 2007. Human parainfluenza was identified in 52(7%) of the samples, which include 9(17,3%) HPIV1, 8(15,4%) HPIV2 and 35(67,3%) HPIV3 17,3% (n=9). Among the 52 cases with parainfluenza, 12 (23%) presented coinfection with other viruses: 3 (25%) coinfection with HPIV3 and VRS, 3 (25%) MPV , 3 (25%) HPIV1 , 1(8,33%) HPIV2 . In addition, it was observed 1(8,33%) of cases with HPIV1 and hVSR; and 1(8,33%) of cases with HPIV2 and hMPV. With respect to the clinical care of the 52 patients with HPIV, 8(5%) were treated at the ER? ; 38(8,4%) at the ENF and 6(18,2%) at the ICU. With respect to gender, a total of 21(5,3%) of the participants with HPIV infections were male and 31(9%) were female. The prevalent age range of participants with infections was 1-23 months of age. The following clinical parameters were observed: bronchiolitis 19(36,5%), pneumonia 13(25%), bronchopneumonia 7(13,4%), dyspnea 2(3,9%) and IVAS 2(3,9%). No clinical information was available for 9(17,3%) cases. HPIV3 infections were detected all year long with an incidence peak in October (Spring). HPIV1 and 2 infections were intercalated during the year. HPIV1 was detected during the first semester with peaks of incidence in April and May whereas HPIV2 was detected during the second semester with peaks of incidence in October, coexisting with HPIV3. HPIV1phylogenetic studies revealed 9 genetic mutations. 4 out of the 9 mutations are exclusively found in the brazilian population. However, only one of these 9 mutations is non-silent and causes a glycine to argenine substitution. When compared to other brazilian sequences in the GenBank, this observation revealed um clado único na topologia da árvore obtida. HPIV3 genotyping included 4 distinct groups detected all year long. All mutations observed in HPIV3 were silent. In conclusion, the parainfluenza virus represent the 3rd major cause of infection of the lower respiratory tract, following the sincicial respiratory virus and the Metapneumovirus.
17

Multivalent sialic acid binding proteins as novel therapeutics for influenza and parainfluenza infection

Alias, Nadiawati January 2014 (has links)
In nature, proteins with weak binding affinity often use a multivalency approach to enhance protein affinity via an avidity effect. Interested in this multivalency approach, we have isolated a carbohydrate binding module (CBM) that recognises sialic acid (known as a CBM40 domain) from both Vibrio cholerae (Vc) and Streptococcus pneumoniae (Sp) NanA sialidases, and generated multivalent polypeptides from them using molecular biology. Multivalent CBM40 constructs were designed either using a tandem repeat approach to produce trimeric or tetrameric forms that we call Vc3CBM and Vc4CBM, respectively, or through the addition of a trimerization domain derived from Pseudomonas aeruginosa pseudaminidase to produce three trimeric forms of proteins known as Vc-CBMTD (WT), Vc-CBMTD (Mutant) and Sp-CBMTD). Due to the position and flexibility of the linker between the trimerization domain and the CBM40 domain, site directed mutagenesis was employed to introduce a disulphide bond between the monomers at positions S164C and T83C of the CBM40 domain in order to promote a stable orientation of the binding site for easier access of sialic acids. Data from isothermal titration calorimetry (ITC) reveals that interaction of multivalent CBM40 proteins with α(2,3)-sialyllactose was mainly enthalpy driven with entropy contributing unfavorably to the interaction suggesting that these proteins establish a strong binding affinity to their ligand minimizing dissociation to produce stable multivalent molecules. However, using surface plasmon resonance (SPR), a mixed balance of entropy and enthalpy contributions was found with all constructs as determined by Van't Hoff plots. This proved that binding does not occur through a simple protein-ligand interaction but through disruption of hydrophobic and/or ionic hydration that provide the driving force to the process. Interestingly, the valency of multiple-linked polypeptides also plays an important part in the protein stabilization. However, little is known about their detailed structure when in multivalent form, as attempts to crystallize the whole protein molecule of Vc-CBMTD (WT) failed due to linker and domain flexibility. Only the trimerization domain (TD) part from Pseudomonas aeruginosa pseudaminidase was successfully crystallized and structure was determined to 3.0 Å without its CBM40 domain attached. In this thesis, we have also reported on the potential anti-influenza and anti- parainfluenza properties of these proteins, which were found to block attachment and inhibit infection of several influenza A and parainfluenza virus strains in vitro. As widely mentioned in literature, terminal sialic acids on the cell surface of mammalian host tissue provide a target for various pathogenic organisms to bind. Levels of viral inhibition were greatest against A/Udorn/72 H3N2 virus for Vc4CBM and Vc3CBM constructs with the lowest EC50 of 0.59 µM and 0.94 µM respectively, however most of the multivalent proteins tested were also effective against A/WSN/33 H1N1 and A/PR8/34 H1N1 subtypes. For parainfluenza virus, all constructs containing V. cholerae sialidase CBM40 domain showed great effect in inhibiting virus infection during cell protection assay. The best EC50 values were 0.2 µM from Vc-CBMTD (WT) followed by 1.17 µM from Vc4CBM and 1.78 µM from Vc-CBMTD (Mutant) which was against hPIV2, hPIV3 and hPIV5 infections respectively. Only a construct from S. pneumoniae sialidase known as Sp-CBMTD showed negligible effect on cell protection. All constructs were further tested for cytotoxicity in mammalian cell culture as well as undergoing an inhibition study on viral replication proteins. For the in vivo study, we also demonstrated the effectiveness of Vc4CBM to protect cotton rats and mice from hPIV3 and Streptococcus pneumoniae infections, when given intranasally in advance or on the day of infection. Therefore, these novel multivalent proteins could be promising candidates as broad-spectrum inhibitors or as a prophylactic treatment for both influenza and parainfluenza associated diseases.
18

Vaccination antigrippale des médecins généralistes étude dans deux régions, la Bretagne et Midi-Pyrénées /

Ty, Phalla Kundh. Mosnier, Anne. January 2006 (has links) (PDF)
Thèse d'exercice : Médecine. Médecine générale : Paris 12 : 2006. / Titre provenant de l'écran-titre. Bibliogr. f. 79-83.
19

Multiplex reverse transcription-PCR for detection and identification of human parainfluenza viruses 1,2,3 and 4 infection in hospitalizedchildren with respiratory disease in Hong Kong

Lam, Siu-yan, 林小欣 January 2007 (has links)
published_or_final_version / Medical Sciences / Master / Master of Medical Sciences
20

Regulation of the human parainfluenza virus (hPIV3) fusion protein

Chapman, Amanda Ruth, January 2008 (has links) (PDF)
Thesis (M.S.)--University of Tennessee Health Science Center, 2008. / Title from title page screen (viewed on January 6, 2009). Research advisor: Charles J. Russell, Ph.D. Document formatted into pages (ix, 41p. : ill.). Vita. Abstract. Includes bibliographical references (p. 38-41).

Page generated in 0.0245 seconds