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Current and future challenges of preventing outbreaks of highly pathogenic avian influenzaDavis, Heather Ann January 1900 (has links)
Master of Science / Department of Diagnostic Medicine/Pathobiology / Alison Paige Adams / Avian influenza (AI) is a zoonotic disease that has garnered much attention in recent years due to its detrimental effects on poultry, producers and potentially human health. This disease can be extremely fatal to domestic poultry, killing as high as 90-100% of the flock. This virus has the potential to cause devastation to and loss of entire flocks. AI is typically spread between wild fowl and domestic poultry with a zoonotic potential to also affect human health as well as other animals. Its spread also has a massive economic impact due to the decreased amounts of available poultry products to consumers around the world. This report will examine the worldwide history and epidemiology of highly pathogenic avian influenza (HPAI). In the last ninety-two years, there have been five recorded outbreaks of HPAI in the United States (US). Globally, notable outbreaks have occurred in Italy (1997-2001), the Dutch region of Europe (2003), Canada (2004), and more recently, in Asia.
Preventative measures will be examined in this report. In particular, biosecurity, quarantine, surveillance, and eradication are some of the most widely recognized and accepted ways to help prevent and control HPAI outbreaks. However, none of these methods are failsafe strategies to completely prevent or control the spread of HPAI. This report will focus on an additional preventative measure - currently available and potential future vaccination programs. There is a global shift toward procuring poultry that are AI-free as well as unvaccinated for AI. This is, in part, due to the limitations of currently available vaccines in completely ridding poultry of this disease. Vaccinations may reduce the amount of virus in infected birds, but this does not prevent birds from becoming infected.
When addressing the control and eradication of HPAI, some future challenges include viral mutations, intermingling of domesticated and wild birds, and vaccine development. Because of the current limitations of vaccines and future challenges in controlling the spread of infection, there is no one single solution to this problem. It will require a multi-faceted approach.
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Características microbiológicas de salmão (Salmo salar) comercializado em algumas cidades da região nordeste do estado de São PauloNespolo, Natália Maramarque [UNESP] 03 July 2009 (has links) (PDF)
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nespolo_nm_me_jabo.pdf: 317079 bytes, checksum: b5a59555adeaded005ddc00b0895ba68 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Tem sido evidente o aumento no consumo de pescado, especialmente do salmão (Salmo salar) sob a forma “in natura”, em pratos da cozinha oriental. Como conseqüência, tem havido maior preocupação quanto às suas características higiênico-sanitárias, tendo em vista a facilidade que microrganismos encontram para se desenvolverem em sua carne, o que pode expor os consumidores a agentes que causam desde uma simples gastrenterite até o óbito. Diante desta preocupação, desenvolveu-se este estudo com objetivos de avaliar características microbiológicas do salmão por meio da quantificação de microrganismos heterotróficos mesófilos, coliformes totais e termotolerantes, o perigo de veiculação de Vibrio parahaemolyticus, Staphylococcus aureus, Salmonella sp., Escherichia coli e Aeromonas sp. através da carne e contribuir com subsídios técnicos para criar uma legislação brasileira com padrões microbiológicos específicos para o pescado consumido cru. Foram colhidas 31 amostras de salmão, 16 refrigeradas e 15 congeladas, no comércio varejista de cidades da região nordeste do estado de São Paulo. Os resultados obtidos mostram populações de microrganismos heterotróficos mesófilos variando entre 1,0 x 10 e 3,9 x 106 UFC/g, coliformes totais e termotolerantes em, respectivamente, 32,24% e 19,33% das amostras e Aeromonas sp. em 35,48% das amostras com variação populacional de 2,0 x 102 a 8,0 x 103 UFC/g. Ainda houve a presença de Staphylococcus aureus em uma amostra e ausência de Vibrio parahaemolyticus, Salmonella sp. e Escherichia coli. Os resultados obtidos podem servir de parâmetro para a criação de um padrão microbiológico específico para o pescado consumido cru e servem também de alerta para os consumidores do produto tendo em vista a veiculação de microrganismos potencialmente patogênicos. / The increasing of seafood consumption has become evident especially in the use of salmon (Salmo salar) consumed raw in oriental dishes. Consequently, it has risen up the concern related to their hygienic-sanitary characteristics due to the facility that microorganisms multiply in the meat which can expose consumers to the causative agents of a mild gastroenteritis until the death. Regarding such informations, this study was aimed to evaluate microbiological characteristics of salmon by quantifying microrganisms heterotrophic mesophiles, total coliforms and thermotolerant. It was also evaluated the danger of transmission of Vibrio parahaemolyticus, Staphylococcus aureus, Salmonella sp., Escherichia coli and Aeromonas sp. on the fish muscle and contributed to technical informations to create a Brazilian regulations about specific microbiological standards for consumption of raw seafood. Thirty-one samples of salmon were collected, 16 chilled and 15 frozen, from the retail market in cities of the northeast region of São Paulo State. The results show populations of mesophilic heterotrophic microorganisms ranging from 1.0 x 10 and 3.9 x 106 CFU/g, in total and fecal coliforms, respectively, 32.24% and 19.33% of samples and Aeromonas sp. in 35.48% of samples ranging population of 2.0 x 102 to 8.0 x 103 CFU/g. Staphylococcus aureus was present in one sample and were not found Vibrio parahaemolyticus, Salmonella sp. and Escherichia coli. The results may serve as a parameter for the establishment of a microbiological standard for the consumption of raw seafood and also as a warning to consumers of the product for the presence of potentially pathogenic microorganisms.
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Acanthamoeba spp. em ambientes hospitalares e acadêmicos do Rio Grande do SulZanella, Janice de Fátima Pavan 20 December 2011 (has links)
Protozoários do gênero Acanthamoeba estão entre os organismos de vida-livre mais abundantes sendo
encontrados em uma ampla gama de ambientes naturais como água, solo, poeira, vegetais, hospitais,
sistemas de ventilação e esgotos. Algumas espécies de Acanthamoeba são consideradas patógenos
oportunistas e têm sido associadas a infecções cutâneas, queratite, encefalite granulomatosa amebiana
(EGA) e a outras afecções em menor frequência. O objetivo do presente trabalho foi avaliar a presença
de Acanthamoeba em áreas comunitárias de unidades acadêmicas e hospitalares, assim como
determinar o risco potencial dos isolados. Amostras foram coletadas em dois hospitais e duas
universidades do Rio Grande do Sul, Brasil. As amebas foram isoladas e caracterizadas utilizando
métodos morfológicos, fisiológicos e genéticos. Além disso, a variação e a especificidade de proteases
extracelulares foram determinadas por análise de zimogramas. A detecção e isolamento de amebas em
amostras clínicas e ambientais envolve a amostragem e cultura em meio ágar não nutriente. Apesar de
eficiente, este sistema requer diversas passagens visando eliminar contaminantes e não é apropriado
para o isolamento de amebas individuais de amostras biodiversas. Para solucionar este problema foi
desenvolvido um método alternativo que envolve amostragem, enriquecimento, indução de
encistamento e micromanipulação de cistos e cultura direta em placas de ágar não nutriente.
Utilizando os métodos convencional e alternativo, 429 amostras de áreas comunitárias de hospitais e
universidades foram avaliadas mostrando alta prevalência de Acanthamoeba tanto em ambientes secos
(13,77%) como úmidos (19,29%). A maior parte dos isolados (77,4%) foram classificados dentro do
grupo II, o qual inclui a maioria das espécies patogênicas. Os isolados apresentaram tolerância à
temperatura e pH, assim como resistência a desinfetantes, características que devem contribuir para a
sobrevivência e proliferação de Acanthamoeba em ambientes fechados, aumentado o risco de
contaminação das pessoas. Como as proteases extracelulares são consideradas um dos mais
importantes fatores de patogenicidade das amebas de vida-livre, dez isolados foram avaliados quanto à
atividade, padrão e especificidade de proteases. Análise com azocaseina mostrou variação significativa
na atividade proteolítica volumétrica e específica dos distintos isolados, independente do “status”
patogênico e não patogênico das espécies. Zimogramas em géis copolimerizados com gelatina
mostraram três padrões de bandas em isolados de
A. castellanii, e perfis particulares para as outras espécies. Todas as proteases secretadas por A.
castellanii, A. pearcei e A. healyi foram caracterizadas como serino proteases, enquanto apenas
cisteino e metaloproteases foram identificadas em A. astronyxis. Algumas proteases extracelulares
apresentaram importante atividade sobre gelatina, fibrinogênio e γ-globulina, e podem estar
implicadas na patogenicidade de Acanthamoeba e na resposta do hospedeiro. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-06-17T12:28:43Z
No. of bitstreams: 1
Tese Janice Zanella.pdf: 1619712 bytes, checksum: 484e08f82e76e04aeafee41542e1e2ac (MD5) / Made available in DSpace on 2014-06-17T12:28:43Z (GMT). No. of bitstreams: 1
Tese Janice Zanella.pdf: 1619712 bytes, checksum: 484e08f82e76e04aeafee41542e1e2ac (MD5) / Protozoa of the genera Acanthamoeba are one of the most abundant free-living organisms. This
microrganisms are found in a wide variety of natural habitats including water, soil, dust, vegetables,
hospital units, ventilation areas and sewage. Some species of Acanthamoeba are considered
opportunistic pathogens, and have been associated with cutaneous infections, keratitis, granulomatous
amoebic encephalitis (GAE), among other less frequent diseases. The aim of this study was to evaluate
the presence of Acanthamoeba in community areas of academic and hospital units, and to determine
their potential risk. Samples were collected from two hospitals and two universities of Rio Grande do
Sul, Brazil. Amoebas were isolated and characterized using morphological, physiological and genetic
methods. Additionally, extracellular proteases variation and specificity was determined by zymogram
analysis. The conventional detection and isolation of amoeba from clinical and environmental samples
involves sampling and culture on non-nutrient Agar medium. Although efficient, this system requires
several transfers in order to eliminate contaminants, and is not appropriate for the isolation of
individual amoeba from samples with a biodiverse community. To solve this problem we developed
an alternative method that involves sampling, enrichment, encystment induction, and direct cysts
micromanipulation and culture on Agar plates. Using the conventional and alternative method, 429
samples from community areas of hospitals and universities were evaluated showing high prevalence
of Acanthamoeba in both dry (13.77%) and humid (19.29%) environments. Most of this isolates
(77.4%) were classified within group II, which includes the great majority of pathogenic species.
Isolates exhibited temperature and pH tolerance, as well as resistance to disinfectants. These
characteristics may contribute for the maintenance and proliferation of Acanthamoeba in the indoor
environments, increasing the risk of people contamination. As extracellular proteases are considered
one of the most important pathogenic factors of free-living amoeba, ten isolates were evaluated to
determined proteases activity, patterns and specificity. Azocasein assays showed significant variation
on the overall and specific protease activity in Acanthamoeba-conditioned media, independently of the
pathogenic or nonpathogenic status of the species. The zymographic assays on gelatin co-polymerized
gels showed three banding patterns for A. castellanii isolates, and specific profiles for other species.
All the proteases secreted by A. castellanii, A. pearcei, and A. healyi were characterized as serine
proteases, but only cisteine and metalloproteases were identified in A. astronyxis. Some extracellular
proteases exhibited important activity on gelatin, fibrinogen and γ-globulin, and may be implicated in
Acanthamoeba pathogenicity and host response.
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Concurrent analysis of the mycotoxins, cyclopiazonic acid, moniliformin and ochratoxin A using capillary zone electrophoresisGovender, Urishani January 2000 (has links)
Submitted in partial fulfillment of the requirements for the degree of Masters in Technology in Chemistry, M.L. Sultan Technikon, 2000. / Mycotoxins are a group of natural poisons produced by certain strains of fungal species when they grow under favourable conditions on a wide variety of different substrates. These toxins have been implicated in a wide range of acute diseases in man and animals. Their toxic effects include oesophageal cancer and liver diseases in humans, and carcinogenic effects in experimental rats and poultry. Hence, there is a need to monitor toxin levels in food commodities. / M
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Acanthamoeba spp. em ambientes hospitalares e acadêmicos do Rio Grande do SulZanella, Janice de Fátima Pavan 20 December 2011 (has links)
Protozoários do gênero Acanthamoeba estão entre os organismos de vida-livre mais abundantes sendo
encontrados em uma ampla gama de ambientes naturais como água, solo, poeira, vegetais, hospitais,
sistemas de ventilação e esgotos. Algumas espécies de Acanthamoeba são consideradas patógenos
oportunistas e têm sido associadas a infecções cutâneas, queratite, encefalite granulomatosa amebiana
(EGA) e a outras afecções em menor frequência. O objetivo do presente trabalho foi avaliar a presença
de Acanthamoeba em áreas comunitárias de unidades acadêmicas e hospitalares, assim como
determinar o risco potencial dos isolados. Amostras foram coletadas em dois hospitais e duas
universidades do Rio Grande do Sul, Brasil. As amebas foram isoladas e caracterizadas utilizando
métodos morfológicos, fisiológicos e genéticos. Além disso, a variação e a especificidade de proteases
extracelulares foram determinadas por análise de zimogramas. A detecção e isolamento de amebas em
amostras clínicas e ambientais envolve a amostragem e cultura em meio ágar não nutriente. Apesar de
eficiente, este sistema requer diversas passagens visando eliminar contaminantes e não é apropriado
para o isolamento de amebas individuais de amostras biodiversas. Para solucionar este problema foi
desenvolvido um método alternativo que envolve amostragem, enriquecimento, indução de
encistamento e micromanipulação de cistos e cultura direta em placas de ágar não nutriente.
Utilizando os métodos convencional e alternativo, 429 amostras de áreas comunitárias de hospitais e
universidades foram avaliadas mostrando alta prevalência de Acanthamoeba tanto em ambientes secos
(13,77%) como úmidos (19,29%). A maior parte dos isolados (77,4%) foram classificados dentro do
grupo II, o qual inclui a maioria das espécies patogênicas. Os isolados apresentaram tolerância à
temperatura e pH, assim como resistência a desinfetantes, características que devem contribuir para a
sobrevivência e proliferação de Acanthamoeba em ambientes fechados, aumentado o risco de
contaminação das pessoas. Como as proteases extracelulares são consideradas um dos mais
importantes fatores de patogenicidade das amebas de vida-livre, dez isolados foram avaliados quanto à
atividade, padrão e especificidade de proteases. Análise com azocaseina mostrou variação significativa
na atividade proteolítica volumétrica e específica dos distintos isolados, independente do “status”
patogênico e não patogênico das espécies. Zimogramas em géis copolimerizados com gelatina
mostraram três padrões de bandas em isolados de
A. castellanii, e perfis particulares para as outras espécies. Todas as proteases secretadas por A.
castellanii, A. pearcei e A. healyi foram caracterizadas como serino proteases, enquanto apenas
cisteino e metaloproteases foram identificadas em A. astronyxis. Algumas proteases extracelulares
apresentaram importante atividade sobre gelatina, fibrinogênio e γ-globulina, e podem estar
implicadas na patogenicidade de Acanthamoeba e na resposta do hospedeiro. / Protozoa of the genera Acanthamoeba are one of the most abundant free-living organisms. This
microrganisms are found in a wide variety of natural habitats including water, soil, dust, vegetables,
hospital units, ventilation areas and sewage. Some species of Acanthamoeba are considered
opportunistic pathogens, and have been associated with cutaneous infections, keratitis, granulomatous
amoebic encephalitis (GAE), among other less frequent diseases. The aim of this study was to evaluate
the presence of Acanthamoeba in community areas of academic and hospital units, and to determine
their potential risk. Samples were collected from two hospitals and two universities of Rio Grande do
Sul, Brazil. Amoebas were isolated and characterized using morphological, physiological and genetic
methods. Additionally, extracellular proteases variation and specificity was determined by zymogram
analysis. The conventional detection and isolation of amoeba from clinical and environmental samples
involves sampling and culture on non-nutrient Agar medium. Although efficient, this system requires
several transfers in order to eliminate contaminants, and is not appropriate for the isolation of
individual amoeba from samples with a biodiverse community. To solve this problem we developed
an alternative method that involves sampling, enrichment, encystment induction, and direct cysts
micromanipulation and culture on Agar plates. Using the conventional and alternative method, 429
samples from community areas of hospitals and universities were evaluated showing high prevalence
of Acanthamoeba in both dry (13.77%) and humid (19.29%) environments. Most of this isolates
(77.4%) were classified within group II, which includes the great majority of pathogenic species.
Isolates exhibited temperature and pH tolerance, as well as resistance to disinfectants. These
characteristics may contribute for the maintenance and proliferation of Acanthamoeba in the indoor
environments, increasing the risk of people contamination. As extracellular proteases are considered
one of the most important pathogenic factors of free-living amoeba, ten isolates were evaluated to
determined proteases activity, patterns and specificity. Azocasein assays showed significant variation
on the overall and specific protease activity in Acanthamoeba-conditioned media, independently of the
pathogenic or nonpathogenic status of the species. The zymographic assays on gelatin co-polymerized
gels showed three banding patterns for A. castellanii isolates, and specific profiles for other species.
All the proteases secreted by A. castellanii, A. pearcei, and A. healyi were characterized as serine
proteases, but only cisteine and metalloproteases were identified in A. astronyxis. Some extracellular
proteases exhibited important activity on gelatin, fibrinogen and γ-globulin, and may be implicated in
Acanthamoeba pathogenicity and host response.
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Caracterização molecular de isolados brasileiros de Escherichia coli aviária / Molecular characterization of Brazilian strains of avian Escherichia coliSilveira, Flávio, 1986- 23 August 2018 (has links)
Orientador: Wanderley Dias da Silveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T07:50:57Z (GMT). No. of bitstreams: 1
Silveira_Flavio_M.pdf: 7271586 bytes, checksum: 61c4ca3b97e4b7443d820cd714394fa8 (MD5)
Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Microbiologia / Mestre em Genética e Biologia Molecular
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Trade-offs in insect disease resistanceCotter, Sheena C. January 2002 (has links)
The ability to mount an efficient immune response should be an important life-history trait as parasitism can impact upon an individual's fecundity and survival prospects, and hence its fitness. However, immune function is likely to be costly as resources must be divided between many important traits. Whilst many studies have examined host resistance to particular parasite types, fewer have considered general immune responses. Studies that have considered general immune responses tend to do so in vertebrate models. However, the complexity of the vertebrate immune system makes the examination of evolutionary aspects of immune function difficult. Using larvae of the genus Spodoptera (Lepidoptera: Noctuidae) as a model system, this study examines' genetic and phenotypic aspects of innate immunity. The aims were to assess the levels of additive genetic variation maintained in immune traits, to consider possible costs that could maintain this variation, and to assess the role of phenotypic plasticity in ameliorating those costs. A key finding of this study was that high levels of additive genetic variation were maintained in all of the measured Immune traits. Analysis of the genetic correlations between traits revealed potential trade-offs within the immune system and between immune components and body condition. In addition, it was shown that larvae living at high densities invest more in immune function than those living in solitary conditions, suggesting that larvae can minimise the costs of immune function by employing them only when the risk of pathogenesis is high.
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Pro-inflammatory cytokine expression as an indicator of bacterial pathogenicity in waterGhoor, Samira 31 March 2010 (has links)
M. Tech. / Background: Waterborne disease contributes significantly to the total global disease burden. Populations in rural areas of South Africa depend on untreated waters for consumption and sanitation. Contamination of public water supplies by harmful bacteria such as pathogenic E. coli poses a major risk for public health. Ingestion of these pathogenic microorganisms present in the contaminated and untreated waters could cause infection, leading to systemic inflammatory responses manifested by the production of various proinflammatory cytokines. To date, there is no human system test available to detect whether water, following ingestion, would cause disease (i.e. whether the water is infectious). The current water testing methods only test for the presence of indicator organisms, such as faecal coliforms, total coliforms, and Escherichia coli. A reliable in-vitro bioassay that could assess whether the water would cause an inflammatory response was investigated in this study. Objectives: Pro-inflammatory cytokines and whole-blood have been used in similar studies to detect the inflammatory responses following exposure to specific stimulants such as dust, lipopolysaccharide (LPS), E. coli and various others. It has been reported that larger numbers of these contaminants induced higher levels of pro-inflammatory cytokine expression. This implies that the pro-inflammatory cytokine expression could be used as a marker of infection since, inflammation occurs in response to infection. Successful infection is thus necessary for inflammation to occur, and high levels of pro-inflammatory cytokine expression confirm that infection has occurred. Thus if pro-inflammatory cytokines could serve as indicators for infection, these cytokines could be used as indicators for bacterial pathogenicity of water.
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Compost Tea 101: What Every Organic Gardener Should KnowJoe, Valerisa, Rock, Channah, McLain, Jean 08 1900 (has links)
5 p. / Growers of organic produce in the Southwestern United States face many challenges, including variation in water and temperature, and exposure to insects and disease. As a result, smallholder organic farmers are increasingly relying on soil additives such as compost tea that improve product quality, use less water, deter pests, and reduce reliance on chemical additives (Diver, 2002). But what exactly is compost tea? Do the benefits of using compost tea outweigh any concerns? For example, can it contain pathogens, and if so, do applicators have to worry about coming into contact with pathogens? This publication provides facts about making compost tea, and reviews both the benefits and potential disadvantages to help smallholder farmers to make educated decisions regarding the use of compost tea.
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Epidemiological and aetiological aspects of diarrhoeal disease in the Eastern CapeBaxter, Esther January 1993 (has links)
Diarrhoeal disease is a major cause of mortality in children in developing countries. It also remains a serious problem among all age groups throughout the world. Whereas studies to determine the epidemiological and aetiological factors of diarrhoeal disease have been reported for other parts of South Africa and the world, as yet no information is available for the Eastern Cape. Therefore this study was undertaken to determine the factors for this area. Enteropathogens were compared for the different ages in the various population groups and, where possible, seasonal and geographical differences were emphasised. A total of 7 278 faecal samples were examined by six laboratories in the Eastern Cape during the period November 1988 to October 1990. Data was recorded noting the age, sex and population group of the patients. The towns selected were Port Elizabeth, Uitenhage, Cradock, Grahamstown and their surrounding areas. The isolation rates for the pathogens studied in the various population groups were compared to those reported in similar studies in other countries. The seasonal incidences of the various selected pathogens were compared with those reported from elsewhere in South Africa. It was thought that the higher temperature of summer may influence the finding in the White population group, while rainfall would play a greater role for the Coloured and Black populations. The geographical distribution of the pathogens emphasised the difference in living conditions between the different population groups. For example a generally higher infestation rate of Helminths occurred in rural areas and in the groups living under poorer conditions. The low isolation rates for certain bacteria and the large percentage of samples from which no pathogens were isolated indicate the need for further research. However, the finding should be valuable for determining Public Health priorities and in the management of outbreaks of diarrhoeal disease.
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