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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.
41

Desenvolvimento e aplicação da técnica de Nested-RT-PCR para a detecção e identificação de variantes brasileiras do vírus da bronquite infecciosa /

Pavani, Caren. January 2017 (has links)
Orientador: Helio José Montassier / Banca: Cintia Hiromi Okino / Banca: Manoel Victor Franco Lemos / Resumo: Em plantéis avícolas, é frequente a ocorrência de doenças infecciosas respiratórias e dentre estas, destaca-se a Bronquite Infecciosa (BI), uma doença aguda e altamente contagiosa de aves. A BI é causada pelo vírus da bronquite infecciosa (VBI), cujo processo infeccioso geralmente provoca perdas econômicas significativas para as criações avícolas. A extensa variação genética, especialmente nas regiões hipervariáveis (HVRs) do gene S1, é uma das principais características da evolução do VBI, e resulta no surgimento de diversas variantes, que requerem um diagnóstico molecular que inclua a detecção dessas novas estirpes, como o genótipo brasileiro (BR-VBI), pois a detecção e identificação do agente etiológico são essenciais para o controle dessa enfermidade. Para tanto, é necessário que os métodos de diagnóstico empregados sejam sensíveis, específicos e de baixo custo. Foi então desenvolvida e avaliada neste estudo uma técnica de Nested-RT-PCR (BR-Nested-RT-PCR) utilizando um conjunto de oligonucleotídeos iniciadores desenvolvido dentro da região HVR3 do gene S1 de estirpes variantes brasileiras do VBI para a detecção e identificação de linhagens do genótipo brasileiro do VBI presentes em amostras biológicas de aves e comparada com a Nested-RT-PCR universal, utilizando oligonucleotídeos iniciadores universais para a mesma região do gene S1. Os resultados demonstraram que a técnica BR-Nested-RT-PCR apresentou uma elevada sensibilidade na detecção de estirpes do genótipo BR-I do V... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Infectious bronchitis (IB) is an acute and highly contagious disease of birds. IB is caused by infectious bronchitis virus (IBV), which usually results in significant economic losses for poultry farms. The extensive genetic variation, especially in the hypervariable regions (HVRs) of the S1 gene, is one of the main characteristics of the evolution of IBV, and results in the appearance of several variants that require a molecular diagnosis which includes the detection of these new strains, such as Brazilian I genotype (BR-I), since the detection and identification of the causative agent are essential for the control of the disease. Therefore, the diagnostic methods used must be sensitive, specific and inexpensive. A Nested-RT-PCR (BR-Nested-RT-PCR) technique was developed and evaluated in this study using a set of primers designed for the HVR3 region of the S1 gene for the detection and identification of Brazilian genotype strains of IBV present in biological samples from birds and compared with universal Nested-RT-PCR using universal primers for the same region of the S1 gene. The results demonstrated that the BR-Nested-RT-PCR technique had a high sensitivity to detect IBV strains from BR-I genotype and did not generate amplified products from heterologous virus samples tested (Newcastle disease virus, avian metapneumovirus, Reovirus and Gumboro disease virus), neither from IBV strains of other genotypes. In addition, the comparison between BR-Nested-RT-PCR techniques with th... (Complete abstract click electronic access below) / Mestre
42

Desenvolvimento da técnica de RT-PCR-ELISA para a detecção do vírus da bronquite infecciosa das aves (VBI)

Luciano, Renato Luís [UNESP] 04 July 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-07-04Bitstream added on 2014-06-13T18:31:25Z : No. of bitstreams: 1 luciano_rl_me_jabo.pdf: 288271 bytes, checksum: 77640cc158f0c12048ecdaf245801057 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Um método de diagnóstico baseado na associação entre as técnicas de RT-PCR e ELISA foi desenvolvido para a detecção do vírus da bronquite infecciosa das aves (VBI). Inicialmente, a especificidade e a sensibilidade analíticas dessa técnica, bem como dos métodos de RT-PCR e Nested-RT-PCR, foram determinadas, tendo-se demonstrado, para o primeiro parâmetro, apenas a detecção do VBI, enquanto que outros vírus heterólogos aviários testados, tais como pneumovírus aviário (APV / estirpe do grupo B), vírus da doença de Newcastle (NDV / estirpe La Sota) e vírus da doença de Gumboro (GDV - estirpe Lukert), não foram detectados. Quanto à avaliação da sensibilidade analítica dos métodos empregados neste estudo foi constatado que o RT-PCR-ELISA demonstrou ser 10 vezes mais sensível do que a RT-PCR, enquanto que a reação de Nested-PCR foi 100 vezes mais sensível que a RT-PCR e 10 vezes mais sensível que o RT-PCR-ELISA. A técnica de RT-PCR-ELISA, juntamente com os outros dois métodos de biologia molecular, foram aplicadas para a detecção das estirpes H-120 e A034 do VBI, em amostras de pulmão e traquéia obtidas de aves experimentalmente infectadas com essas duas estirpes virais. Os resultados obtidos nos diferentes métodos de biologia molecular foram comparados entre si e com a técnica padrão de isolamento viral em ovos embrionados, verificando-se que o RT-PCR-ELISA revelou-se tão específico quanto as técnicas de isolamento viral e Nested-PCR, porém foi menos sensível do que esses mesmos métodos na detecção do VBI. A técnica de RT-PCR-ELISA, utilizada pela primeira vez para o VBI, demonstrou o potencial de se constituir uma alternativa viável para um diagnóstico direto mais rápido e específico do VBI. / A molecular biology method for the detection of avian infectious bronchitis virus (IBV) was developed combining the reverse transcription and polymerase chain reaction (RT-PCR) with the enzyme-linked immunosorbent assay (ELISA). Firstly, the analytical specificity and sensitivity of RT-PCR-ELISA, RT-PCR and Nested-RT-PCR were assessed. The specificity of these methods were confirmed since only IBV was detected, while other heterologous avian viral pathogens such as pneumovirus (Group B), Newcastle disease virus (LaSota strain) and gumboro disease virus (Lukert strain) were not detected by these techniques. The sensitivity of these methods was established, indicating that the RT-PCR-ELISA was about ten times more sensitive than conventional RT-PCR, while Nested-PCR was a hundred more sensitive than RT-PCR and ten times more sensitive than PCR-ELISA. The RT-PCR-ELISA and the two molecular biology methods were also applied for the detection of IBV strains H-120 and A034, in lung and tracheal tissue samples collected from experimentally infected chickens. The results of these different methods were also compared with the standard diagnostic technique, the virus isolation in chicken embryonated eggs, showing that RT-PCR-ELISA was as specific as virus isolation and Nested-PCR, however it was less sensitive than these methods for the IBV detection. The RT-PCR-ELISA, applied for the first time for IBV detection and direct diagnosis in tissue samples, can be potentially applied as an useful alternative for the rapid and specific diagnosis of IBV.
43

Expressão da proteína S1 recombinante do vírus da bronquite infecciosa em Saccharomyces cerevisiae para aplicação no imunodiagnóstico /

Oliveira, Andressa Peres de. January 2008 (has links)
Orientador: Hélio José Montassier / Banca: Ana Maria Iba Kanashiro / Banca: José Moacir Marin / Resumo: A glicoproteína de superfície (8) do vírus da bronquite infecciosa (VBI) em aves; é um alvo antigênico importante para a indução de imunidade e como antígeno utilizado no imunodiagnóstico da infecção causada por este vírus. Nesse estudo, a forma recombinante da subunidade 81 da glicoproteína 8 da estirpe M41 do VBI foi clonada e expressa como proteína de fusão contendo uma cauda de poli-histidina e o epítopo V-5 em células da levedura Saccharomyces cerevisiae. O gene codificador dessa proteína foi amplificado a partir do RNA genômico da estirpe M41 do VBI, por meio das técnicas da reação de transcrição reversa (RT) e da reação da polimerase em cadeia (PCR). Foi amplificada toda a seqüência codificadora de interesse e fossem geradas extremidades compatíveis com a inserção no vetor pYE82.1N5-His-TOPO. Este vetor foi usado na transformação de leveduras, tendo sido obtidos os clones transformantes específicos portadores do inserto gênico. A expressão da proteína de fusão foi então induzida, em células de S. cerevisiae, sendo produzida a proteína recombinante 81 de fusão com peso molecular 95 kDa. Essa proteína apresentou com uma elevada reatividade cruzada para a proteína 8 do próprio vírus, tal como demonstraram os resultados das análises pelo Western blotting e ELl8A. Essa proteína de fusão foi, devido à presença da cauda de poli¬histidina, prontamente purificada por cromatografia de afinidade em coluna de níquel ¬agarose e, posteriormente utilizada com sucesso no desenvolvimento de um método indireto de ELl8A para a detecção de anticorpos específicos de galinhas infectadas com o VBI. / Abstract: The surface glycoprotein of infectious bronchitis virus (IBV) is a important antigenic target for the induction of immunity and as antigen in the immunodiagnosis of infection caused by this virus. In this study, the gene of 51 glycoprotein of M41 strain of the IBV was cloned and expressed as a fusion protein containing a poly-histidine and epitope V-5 tags in the yeast cells of Saccharomyces cerevisiae. The 51 gene was amplified from genomic RNA of the M41 strain of VBI, by reverse transcription (RT) and polymerase chain reaction (PCR). The entire coding sequence of 51 gene was amplified and inserted in the vector pYE52.1N5-His-TOPO. This construct was used for transforming yeast cells, and to obtain specific clones carrying the inserted gene. The expression of the fusion protein was induced in transformed cells of S. cerevisiae, and a recombinant 51 protein was produced with a molecular weight of 95 kDa. A high cross¬reactivity with the original 51 protein from the virus was detected by Western blotting and ELl5A. The presence of the poly-histidine tail in the fusion recombinant protein favored their prompt purification by affinity chromatography in a column of nickel¬sepharose. This recombinant 51 protein was successfully used in the development of an indirect method of ELl5A for the detection of specific anti-IBV antibodies in chickens experimentally infected or vaccinated with this virus. / Mestre
44

Caracterização e comparação molecular de estirpes de referência e de campo do vírus da bronquite infecciosa das galinhas / Molecular characterization and comparison of reference and field strains of infectious bronchitis vírus

Sueli da Silva Santos 02 February 2012 (has links)
A bronquite infecciosa é uma doença viral, aguda e altamente contagiosa que afeta as aves da espécie Gallus gallus, de todas as idades, causando grandes perdas econômicas devido à mortalidade, queda na produção e qualidade dos ovos. Variações na sequência de aminoácidos na região hipervariável da subunidadade S1 da proteína de espícula (S) levam à emergência de novos sorotipos do vírus da bronquite infecciosa das galinhas (IBV). Este estudo teve como objetivo seqüenciar parcialmente o gene S1 para determinar a relação filogenética entre amostras vacinais e de campo com o intuito de investigar os genótipos circulantes. Cento e sessenta amostras foram coletadas, na forma de pools, de plantéis sintomáticos durante 2009/2010. Cada pool continha tecidos de 3 a 5 aves e foram compostos por diferentes órgãos (traquéia, pulmões, rins, conteúdo entérico, trato reprodutivo e swabs traqueais). As amostras foram triadas para a presença de IBV utilizando-se uma nested RT-PCR, direcionada a região 3UTR. As amostras positivas, (n=89) foram submetidas a nova nested RT-PCR dirigida para o gene S, resultando em 10 amplicons de 390pb que foram então submetidos a seqüenciamento de DNA e análise filogenética. As amostras brasileiras segregaram-se em dois grupos filogenéticos: Massachusetts (Mass) e tipos marcadamente brasileiros. Seis amostras agruparam-se no grupo Mass, com vacinas vivas atenuadas utilizadas no Brasil. Quatro amostras agruparam com cepas de campo brasileiras previamente descritas (acesso no GeneBank: FJ791257 to FJ791273). A identidade de aminoácidos no grupo Mass variou de 98% a 100%, sugerindo a detecção de vírus vacinal. Enquanto que entre as amostras brasileiras e o grupo Mass, a variabilidade de aminoácidos foi de 79% a 81%. Esses resultados mostram uma variação importante em genótipos virais circulantes nos plantéis industriais avícolas brasileiros. Portanto, o presente estudo reforça a contínua emergência e disseminação de novas linhagens de IBV no Brasil e a importância de constantes pesquisas e monitoramento, para que se compreendam aos fenômenos de emergência de novas linhagens e suas consequências, bem como para otimizar as medidas de controle do vírus. / Infectious bronchitis is a viral disease, acute and highly contagious that affects birds of the Gallus gallus species, of all ages, causing huge economic losses due to mortality, drop in production and quality eggs. Differences between serotypes of IBV are due to variations in the amino acids sequence in S1 hypervariable region subunit of spike protein (S). This study aimed to partially sequence the S1 gene to determine the phylogenetic relationship between field and vaccine viral types, and to investigate circulating genotypes in Brazil. One hundred and sixty pool samples were collected from symptomatic flocks during 2009/2010. Each pool contained tissues from 3 to 5 birds and was composed by different organs (tracheas, lungs, kidneys, enteric contents, tract reproductive and tracheal swabs). Samples were screened for the presence of IBV using a nested RT-PCR targeted to the 3UTR. Positive samples (n=56) were submitted to a nested RT-PCR target to S gene resulting in 10 amplicons of 390pb that were then submitted to DNA sequencing and analysis. Brazilian IBV genotypes segregated in two phylogenetic groups: Massachusetts (Mass) and Brazilian types. Six samples clustered in the Mass group, with live attenuated vaccines used in Brazil. Four samples grouped with field Brazilian strains previously described (GeneBank accession: FJ791257 to FJ791273). In Mass cluster aminoacids identity range from 98% to 100%, suggesting vaccine virus detection, in this last case. Moreover, the verified identity between samples from this study and Mass group ranged 79% to 81%. Therefore the present study reinforces the emergence and circulation of news lineages of IBV in commercial Brazilian flocks, as well as the importance of consistent research and monitoring to better understand this phenomen and its consequences, aiming to improved control measures against the virus.
45

Características patogênicas e moleculares de variantes brasileiras do vírus de bronquite infecciosa inoculados em aves comerciais e SPF. / Pathogenic and molecular characteristics of brazilian variant infectious bronchitis isolates inoculated in commercial and SPF birds.

Mário Sérgio Assayag Júnior 08 December 2009 (has links)
A bronquite Infecciosa das galinhas (BIG) é uma doença respiratória aguda e altamente contagiosa que acomete galinhas de diferentes idades. Foram utilizadas duas amostras do VBIG de problemas respiratórios e entéricos em frangos. As amostras foram classificadas como variantes do VBIG através da técnica de RT-PCR multiplex e sequenciamento parcial do gene S1. As amostras foram inoculadas em frangos de corte e aves SPF (specific pathogen free). As aves apresentaram sinais respiratórios 36 horas após inoculação independente da origem viral, entérica ou respiratória, sendo mais discretos nas aves SPF. As alterações macroscópicas mais evidentes foram congestão da mucosa traqueal, pulmão e rins. A análise histopatológica mostrou lesões semelhantes àquelas encontradas em outros sorotipos. A análise filogenética mostrou que as duas amostras eram similares e diferentes das amostras Massachusetts. Esses resultados sugerem que os isolados classificados como variantes apresentam potencial patogênico para aves. / Infectious bronchitis (IB) is an acute respiratory disease, highly contagious which affects chickens of different ages. This study was composed with two isolates obtained from broilers with respiratory and enteric problems. These isolates were classified as IBV variants by the multiplex RT-PCR and by sequencing of S1 gene. Isolates were inoculated in broilers and SPF birds. The birds showed respiratory signs 36 hours post inoculation, independently of the enteric or respiratory source. The respiratory signs were less evident on SPF birds. The histopathology analysis showed significant lesions on the trachea, lungs and kidneys. The phylogenetic analysis of S1 gene showed that both isolates were similar and different from Massachusetts strains. These results suggest that the isolates classified as variant have pathogenic potential for birds.
46

Variation of active constituents in Euclea natalensis based on seedling stages, seasons, and fertilizers

Bapela, Mahwahwatse Johanna 26 June 2008 (has links)
Euclea natalensis A.DC. belongs to the Ebenaceae family, and is extensively distributed along the eastern coast of southern Africa. Many Euclea species are widely gathered by indigenous people because of their medicinal properties. Roots of these plant species are frequently used to treat respiratory complications such as chest pains, bronchitis, pleurisy and asthma. Ground root powder is topically applied in cases of leprosy and is used by some ethnic groups to treat toothache and headache. The bioactivity encountered is attributable to naphthoquinones, which are common phenolic compounds in the Ebenaceae family. Naphthoquinones isolated from E. natalensis (shinanolone, 7-methyljuglone, diospyrin, isodiospyrin and neodiospyrin) have exhibited a broad spectrum of antimicrobial activity. The demand for these products will escalate due the amount of plant material required to further research. We need to explore techniques that can maximize their productivity. The present study was conducted on E. natalensis, in an attempt to establish if there exists any correlation between the accumulation of naphthoquinones and stages of seedling growth, seasonal fluctuations and application of fertilizers. A possible correlation between seedling growth stages and the accumulation of naphthoquinones (shinanolone, 7-methyljuglone and diospyrin) was investigated in seeds and seedlings of Euclea natalensis. In this study, the seeds represented the first stage, whereas the second seedling stage was defined as the stage when the radicles were about 6 cm long. The lengths of the seedlings at the third, fourth and fifth seedling stages were 9 cm, 12 cm and 16 cm respectively. Plant materials collected from the five seedling stages were separately extracted using chloroform and the naphthoquinones were then quantified by means of High Performance Liquid Chromatography (HPLC). Mobile phase of MeCN: H2O: AcOH (62.5: 32.5: 5) was used as an eluent in an isocratic mode and at a flow rate of 0.8 ml/min. Standard curves of each of the four compounds were obtained by making a series of dilutions in the concentration range of 22.5 µg/ml to 2.25 µg/ml. Ten microlitres of each dilution was injected three times into the HPLC, and the run time for each injection was 20 minutes. Calibration curves were then generated and used for the quantification of each compound. Shinanolone, which was the only naphthoquinone detectible in seeds, accumulated at variable rates (P<0.01) and no trend could be established between its synthesis and seedling growth. The content of shinanolone ranged from 87.5 mg/kg dry weight (dw) in seeds to a high mean value of 1047 mg/kg (dw) during the fourth seedling stage. A significant correlation (P<0.01) was found between the mean concentrations of 7-methyljuglone and seedling growth. 7-Methyljuglone was quantified at a high mean level of 5003 mg/kg during the third seedling stage and was not detected in the seed samples. A positive correlation (P<0.01) was established between the concentration of diospyrin and seedling stages. Diospyrin was detected at an elevated mean concentration of 6182 mg/kg during the fifth seedling stage, which was higher than the other quantified naphthoquinones. Seasonal variation of naphthoquinones (shinanolone, 7-methyljuglone, diospyrin, isodiospyrin and neodiospyrin) was investigated from eleven plants of E. natalensis subsp. natalensis growing in natural populations, over a period of four seasons. The roots were harvested, dried, extracted and analysed as in the previous study. The mean levels of shinanolone and 7-methyljuglone were found to be uniform in all the seasons and no statistically significant variation could be found between seasonal changes and their mean concentrations. Accumulation of isodiospyrin and neodiospyrin varied significantly with seasonal changes (P<0.05). These two bioactive naphthoquinones were detected only in summer and autumn respectively, and not in winter. A statistically significant variation (P<0.05) was established between the levels of diospyrin and seasonal fluctuations. Diospyrin was detected at a mean concentration of 3190 mg/kg (dw) during spring, which was higher than the other naphthoquinones quantified in all four seasons. The effect of NPK fertilizers on growth performance and accumulation of naphthoquinones (shinanolone, 7-methyljuglone, diospyrin, isodiospyrin and neodiospyrin) in seedlings of E. natalensis grown in shade and under field conditions was investigated. Each group was subdivided into four subgroups, which were then subjected to four respective treatments of water-soluble foliar feed (2:1:2 (44) NPK) at three different concentrations. Treatments tested were as follows: Treatment 1 at 40 g/l, Treatment 2 and Treatment 3 at 20 g/l and 10 g/l respectively. The control group received only supplemental water. The first harvest was conducted after 6 months of application of fertilizers and the second one was done after 12 months of treatment. Roots and shoots were harvested and analysed separately. The naphthoquinones were quantified as previously described. The bioactivity of root extracts from seedlings was tested against Mycobacterium smegmatis and extracts with lower MIC were further tested on M. tuberculosis. Growth parameters differed between the two groups, with seedlings from the shadehouse showing more plant vigour than the field grown plants. No significant interaction could be established between the measured growth factors and treatment. A significant interaction (P<0.001) was found between Treatment 2 and shadehouse seedlings. Treatment 2 enhanced vegetative performance with the mean values of fresh weight of shoots and roots being twice as much as their respective control mean values. A significantly positive correlation was established between the concentration of shinanolone (P<0.01), isodiospyrin (P<0.05) and neodiospyrin (P<0.05) with fertilization from field-grown seedlings. Application of NPK fertilizers significantly (P<0.05) increased the accumulation of neodiospyrin in seedlings subjected to shadehouse conditions. The most potent naphthoquinone, 7-methyljuglone, was found to be abundant in all the extracts and was quantified at a high mean concentration of 10200 mg/kg from shadehouse seedlings. Root extracts of E. natalensis seedlings grown under field conditions were generally more active against the bacterial strain of M. smegmatis as compared to extracts acquired from roots of seedlings maintained under a shadehouse setting. A lowest minimum inhibitory concentration (MIC) of 0.78mg/ml against M. smegmatis was observed from the second harvest of field-cultivated seedlings of the control and Treatment 1 subgroups. The MIC values for shadehouse seedlings ranged from 1.6 to 6.3 mg/ml. Minimum bactericidal concentration (MBC) values from all the extracts tested were relatively higher than their respective MIC’s. Root extracts of E. natalensis were more active against M. tuberculosis and their MIC values were lower than the tested concentrations. Extracts acquired from field-grown seedlings were more active against M. smegmatis with a lowest MIC value of 0.78 mg/ml. Extracts from the control group and Treatment 1, which had less application of fertilizers were more active against strains of M. tuberculosis with MIC value of 10 µg/ml. This shows the selectivity of E. natalensis against the mycobacterial strain of M. tuberculosis. Based on the findings, synthesis and accumulation of naphthoquinones in E. natalensis is highly variable within individuals of the species investigated. Naphthoquinones accumulate in relatively higher amounts in roots of E. natalensis than in the aboveground structures, which validate their harvest by indigenous people. The concentration of shinanolone varied slightly and its production increased with seedling growth. The synthesis of 7-methyljuglone is independent of fertilisation as its accumulation was enhanced in seedlings subjected to control treatment. Neodiospyrin and isodiospyrin were always present in every sample obtained from the seedlings but they were not detectible in every profile of samples from mature plants. Diospyrin is the only naphthoquinone that was detected in every sample analysed and also quantified in high concentrations from mature plants harvested in spring. The study showed that depending on the requirement of a particular naphthoquinone for research, one could target the seasons and seedling stages recommended from this study. This study also showed that field-cultivated seedlings produced more potent naphthoquinones than the ones subjected to controlled environments. / Dissertation (MSc (Plant Science))--University of Pretoria, 2008. / Plant Production and Soil Science / unrestricted
47

Investigation into the variation of infectious bronchitis virus serotypes in KwaZulu-Natal poultry flocks

Knoetze, Adrian David January 2013 (has links)
Infectious bronchitis virus (IBV) is a member of family Coronaviridae and is classified into group 3 of the Coronaviruses. The virus is a single-stranded positive-sense RNA virus with a genome of 27kbp. IBV is a highly infectious disease of chickens that results in high morbidity with moderate to severe mortality depending on the strain involved, age of the birds, and immune status of the chickens. Multiple worldwide investigations indicate that differentiation within the S1 glycoprotein gene can lead to serotype variation within the IBV species. In this study 46 isolates collected over two years from broiler and broiler breeder flocks and eight historical isolates were analyzed. Forty one isolates originated from the KwaZulu-Natal region whilst the remaining thirteen were isolated from 4 other poultry-dense provinces. The S1 gene was sequenced and compared to determine variation between South African isolates, as well as global sequences submitted to Genbank. The results indicate the division of isolates analyzed into 2 different clades of IBV within the province. The most prevalent genotype was similar to IBV Mass strain detected in 79% of the full S1 sequences. Variation up to 22.3% was detected within local strains, supporting the hypothesis that multiple IBV serotypes may co-circulate in the same region simultaneously. Additionally, more conservation was observed among Mass serotypes versus QX-like serotypes, implying that vaccine use can influence the variability within the IBV population. Higher variability was found in the first half of the S1 gene in comparison to the last half of the S1 gene. This is in agreement with previous findings that the hypervariable regions of the S1 gene are located within the first 450 base pairs. This study offers the first published consolidation of IBV isolates from South Africa and identifies variation within the IBV population of the SA broiler flock. Previous publications list four or five IBV isolates whilst this study describes variation found in 54 isolates spanning 32 years. In addition this study provides the insight into the prevalence of IBV variation in poultry flocks due to the large number of isolates. The comparative use of geno- and serotyping for South African IBV isolates is also described for the first time in this study. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Veterinary Tropical Diseases / unrestricted
48

Gender Differences in the Associations of Early Onset Poly Tobacco and Drug Use Prior to Age 18 With the Prevalence of Adult Bronchitis in the United States

Ategbole, Muyiwa, Su, Brenda Bin, Wang, Nianyang, Loudermilk, Elaine, Xie, Xin, Acevedo, Priscila, Ozuna, Kaysie, Xu, Chun, Liu, Ying, Wang, Kesheng 01 January 2020 (has links)
Purpose: We investigated the associations of early onset polysubstance use prior to age 18 with the prevalence of bronchitis among U.S. adults and tested whether the associations differ by gender. Methods: A total of 77,950 adults, of them 2,653 with bronchitis in the past year, were from the combined 2013 and 2014 National Survey on Drug Use and Health data. The variable cluster analysis was used to classify nine variables about substance use prior to age 18 (cigarettes, cigars, smokeless tobacco, marijuana, cocaine, heroin, methamphetamines, ecstasy, and phencyclidine). Weighted multivariate logistic regression analysis (MLR) was used to examine the associations with bronchitis. Results: Nine variables were divided into two clusters: early onset poly tobacco use (three tobacco use variables) and early onset poly drug use (six drug use variables). The overall prevalence of bronchitis was 3.8% (5.1% for females and 2.3% for males). MLR analysis showed that being female, elderly (ages 65 and above), obese, and early onset poly tobacco use were associated with increased odds of bronchitis (p < 0.05). Gender-stratified analyses showed that early-onset poly tobacco use was significantly associated with bronchitis only in males, whereas early onset poly drug use was associated with bronchitis only in females. Moreover, obesity and tobacco use in the past year revealed associations with bronchitis regardless of gender. Conclusions: Obesity, early onset poly tobacco use prior to age 18, and tobacco use in the past year were positively associated with bronchitis; furthermore, the associations of early onset polysubstance use with bronchitis differed by gender, which indicated that gender differences should be considered in developing effective prevention strategies.
49

The Relationship Between PM2.5 and Chronic Respiratory Disease in Senegal

Glenn, Bailey 28 June 2022 (has links)
Chronic respiratory diseases such as asthma and chronic bronchitis have significantly increased in prevalence in Africa over the past 10 years. Recent studies have demonstrated that exposure to air pollution may be associated with an increased risk of chronic respiratory diseases. However, such studies have predominantly been conducted in western societies or often used urbanicity as a proxy for exposure to air pollution. Therefore, we evaluated the association between PM2.5 exposure and asthma/chronic bronchitis in Senegal. A cross-sectional study was conducted for the time period of 3 October 2010 to 28 April 2011 using annual concentrations of PM2.5 measured via multiple satellite instruments, and asthma/chronic bronchitis, which was self-reported at baseline via a health survey questionnaire. We used mixed model logistic regression to evaluate the relationship between PM2.5 exposure and asthma/chronic bronchitis risk while adjusting for lifestyle factors, location, and other air pollutants. Sex was evaluated as an effect modifier. The adjusted association between PM2.5 and asthma/chronic bronchitis was 1.03 (95%CI: 0.99 – 1.06). In males the adjusted odds ratio was 1.09 (95%CI: 1.03-1.15), compared to females (aOR 1.01 (95%CI: 0.97 – 1.05). Our results suggest that increasing levels of exposure to PM2.5 puts individuals at a higher risk for chronic respiratory diseases, especially men. These findings have significant policy implications and should be built upon in future research.
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Diagnostik und Therapie von Atemwegsinfekten in der Allgemeinarztpraxis / Diagnosis and treatment of respiratory tract infections in general practice

Fischer, Susanne 01 November 2003 (has links)
Einleitung: Atemwegsinfekte gehören zu den häufigsten Krankheitsbildern in der Allgemeinarztpraxis. Ziel der Erhebung war es, Daten zur Diagnostik und Therapie von Atemwegsinfekten in der hausärztlichen Praxis zu erheben. Methoden: Während einer jeweils eintägigen Hospitation bei 30 Fachärzten für Allgemeinmedizin wurde deren Vorgehensweise bei allen Patienten mit einem akuten Atemwegsinfekt dokumentiert, die im Zeitraum der Beobachtung den Arzt konsultierten. Es erfolgte eine Unterscheidung zwischen Erst- und Folgekontakten. Ergebnisse: Diagnostisch wurden am häufigsten die Auskultation der Lunge und die Inspektion des Mund-Rachen-Raumes durchgeführt. 98,4% der Patienten mit Erstkonsultationen und 62,5% der Patienten mit Folgekonsultationen erhielten eine medikamentöse Verordnung. Im Durchschnitt erhielten erstkonsultierende Patienten 2,1 (+-1,0), Patienten im Folgekontakt 1,3 (+-1,1) Medikamente. Am häufigsten wurden Medikamente aus der Gruppe der Husten- und Erkältungspräparate verordnet (87,1% der Erstkontakte und 52,9% der Folgekontakte). 43,5% der Erstkontakte und 29,9% der Folgekontakte erhielten ein Antibiotikum (37,5% Makrolide, 21,5% Penicilline, 20,8% Doxycyclin als Monosubstanz oder in Kombination mit Expektorantien). Schlussfolgerung: Nahezu alle Patienten erhielten ein Rezept über mindestens ein Medikament. Die erhobenen Daten lassen vermuten, dass sich bei einer höheren Gewichtung der so genannten "Hausmittel" ein deutliches Einsparungspotential böte. Angesichts des hohen Anteils der Antibiotikaverordnungen sollte die entsprechende Indikationsstellung kritisch überdacht werden.

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