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Epidemiologia da esquistossomose em três municípios da microrregião de Juiz de Fora, Minas GeraisTibiriçá, Sandra Helena Cerrato 26 September 2008 (has links)
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Previous issue date: 2008-09-26 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / A epidemiologia da esquistossomose apresentou transformações significativas nas últimas décadas no Brasil. No Estado de Minas Gerais, a redução da morbi-mortalidade e o desenvolvimento tecnológico dos meios diagnósticos e terapêuticos foram evidentes, mas não suficientes para impedir a expansão geográfica da endemia. Clinicamente, a esquistossomose pode se manifestar com as formas agudas e as crônicas hepatoesplênicas, estas mais freqüentes nas áreas de altas endemicidades. Outra forma incapacitante e subnotificada é a mielorradiculopatia esquistossomótica, que ocupa papel de destaque pela gravidade potencial e possibilidade de ocorrer também em áreas de baixas endemicidades, já que não depende da intensidade da infecção. Considerando a população residente, foi realizado um levantamento seccional objetivando determinar a prevalência, a intensidade da esquistossomose e a
distribuição dos hospedeiros intermediários em três municípios da microrregião de Juiz de Fora. Utilizou-se estudo amostral baseado no cadastro das famílias no SIAB, com investigação de 850 famílias por meio de exames coproparasitológicos pelo método Kato-Katz e aplicação de questionário estruturado. Este estudo validou a utilização do cadastro das famílias no SIAB como base populacional para cálculo amostral na realização de pesquisas de campo. Foi pioneiro na verificação da prevalência média de 2,4% da esquistossomose mansoni nos municípios de Piau (2%), Goianá (2,1%) e Coronel Pacheco (3,1%). As características da transmissibilidade na região foram avaliadas e descritas. Os infectados predominaram na população adulta jovem, somente 10% dos escolares foram positivos e não constituíram indicadores dos domicílios com adultos doentes. Os resultados obtidos permitiram identificar o padrão de agregação, revelando os indivíduos com as maiores cargas parasitárias. As três espécies de moluscos de importância epidemiológica foram identificadas nas áreas estudadas: B. glabrata, B. straminea, e B. tenagophila. Constatou-se que, nas situações de baixa endemicidade, em municípios com população inferior a 5.000 habitantes e cobertos pela estratégia de saúde da família, a pesquisa da prevalência da esquistossomose v com base no estudo amostral a partir do cadastro das famílias no SIAB é apropriada para identificar os grupos de maior transmissão. Os indivíduos infectados foram espacialmente referenciados com os moluscos potenciais hospedeiros e indicaram os focos de maior transmissibilidade da esquistossomose nos municípios estudados. / The epidemiology of schistosomiasis has undergone significant transformation in recent decades in Brazil. In the state of Minas Gerais there has been a decline in morbi-mortality, along with advances in diagnosis and treatment, but these have not been sufficient to prevent the geographic spread of the endemic. Clinically, schistosomiasis can appear in acute and chronic hepatosplenic forms, the latter more frequent in areas of high endemicity. Another incapacitating and underreported form, schistosomotic myeloradiculopathy, deserves attention because of its potential severity and the fact it can also occur in areas with low endemicity, since it does not depend on the infection’s intensity. A cross-sectional study was carried out to determine the prevalence and intensity of schistosomiasis in the resident population and the distribution of intermediate hosts in three municipalities in the Juiz de Fora micro-region. The sample was drawn from families listed in the Basic Health Service Information System
(SIAB), from which 850 families were investigated through coproparasitological tests by the Kato-Katz technique and the application of a structured questionnaire. This study was groundbreaking in verifying an average schistosomiasis mansoni prevalence of 2.4% in the municipalities of Piau (2%), Goianá (2.1%) and Coronel Pacheco (3.1%). The transmissibility characteristics in the region were evaluated and described. The infected individuals were predominantly young adults. Only 10% of the school-age subjects were positive and there were no indicators of households with sick adults. The results permitted identifying the pattern of aggregation, revealing the individuals with greater parasite loads. The three species of snail carriers were identified in the areas studied: B. glabrata, B. straminea, and B. tenagophila. Therefore, in situations of low endemicity, in regions with population under 5,000 people and covered by family preventive health programs, the study of the prevalence of schistosomiasis
based on sample data from households listed in the SIAB is appropriate to identify the groups of greater transmission. The infected individuals were spatially referenced together with the host snails, indicating the probable foci of greatest transmission in the municipalities studied.
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Enteroparasitoses em comunidades indígenas brasileirass / Intestinal parasites in Brazilian indigenous communitiesMalta, Roberto Carlos Grassi, 1970- 19 August 2018 (has links)
Orientadores: Manzélio Cavazzana Júnior, Regina Maura Bueno Franco / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T19:07:23Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: As infecções parasitárias são um dos principais problemas de saúde pública, apresentando-se de forma endêmica em diversas áreas do Brasil. Podem apresentar estreita relação com fatores sócio-demográficos e ambientais, tais como: precárias condições socioeconômicas, consumo de água contaminada, deficiente estado nutricional dos indivíduos e outros, sendo frequentemente a população infantil a mais atingida. Com o objetivo de investigar a prevalência de parasitas intestinais em populações indígenas e populações carentes e os fatores-chave envolvidos na epidemiologia de enteroparasitoses, foi realizado levantamento enteroparasitológico em moradores de 02 reservas indígenas Reserva Bororó/MS e Reserva Xingu/MT (tribos Kayabí e Juruna) -, e também em moradores de 02 cidades - Pontes e Lacerda/MT e Ibateguara/AL. A coleta de dados foi realizada de 2002 a 2009. Foram analisadas 2754 amostras de fezes pelos métodos de Faust, Hoffman, Kato-Katz, Rugai, Direto e Ziehl-Neelsen modificado. Foram obtidos dados pessoais e parâmetros socioeconômicos. Observou-se a presença de 73% de enteroparasitas na reserva indígena de Dourados, 62,77% na reserva indígena do Xingu, 52,61% no município de Pontes e Lacerda/MS e 67,42% no município de Ibateguara. As espécies de maior prevalência no sexo masculino foram Entamoeba coli (22,5%), Giardia duodenalis (11,6%), Entamoeba histolytica (13,9%) e Ascaris lumbricoides (13,6%). No sexo feminino foram Entamoeba coli (24,1%), Giardia duodenalis (8,8%), Entamoeba histolytica/díspar (13,8%) e Ascaris lumbricoides (13,3%). A prevalência de protozoários (42,6%) foi maior que de helmintos (31,1%). Para a maioria dos grupos analisados não houve diferença entre o quadro clínico de diarreia e o tipo e número de enteroparasita. O poliparasitismo foi detectado em 12,8% das amostras e o monoparasitismo em 46,5%. Os grupos etários de menor idade apresentaram predomínio de infecções por protozoários / Abstract: The parasitic infections are the major public health problems, presenting an endemic form in several areas of Brazil. They may present narrow relationship with social-demographical and environmental factors, such as: social-economical precarious conditions, consumption contaminated water, deficient nutritional condition of individuals and others, being frequently the infant population the most affected. In order to investigate the prevalence of intestinal parasites in indigenous and deprived populations and the key factors involved in the epidemiology of intestinal parasites, it was realized intestinal parasitological survey in residents of two Indian reservations: Bororó Reservation/MS and Xingu Reservation/MT (Kayabí and Juruna tribes); and also in residents of two cities: Pontes e Lacerda/MT and Ibateguara/Al. The data collection was conducted from 2002 to 2009. 2,754 faeces samples were analyzed by the methods of Faust, Hoffman, Kato-Katz, Rugai, Direct and modified Ziehl-Neelsen. The study obtained personal data and social-economical parameters. It was observed the presence of 73% of intestinal parasites in the Bororó Reservation, 62.77% in the Xingu Reservation, 52.61% in the cities of Pontes e Lacerda/MS and 67.42% in the Ibateguara city. The species of most prevalence in male individuals were Entamoeba coli (22.5%), Giardia duodenalis (11.6%), Entamoeba histolytica (13.9%) and Ascaris lumbricoides (13.6%). In female individuals were Entamoeba coli (24.1%), Giardia duodenalis (8.8%), Entamoeba histolytica/ E. díspar (13.8%) and Ascaris lumbricoides (13.3%). The prevalence of protozoan (42.6%) was higher than helminths (31.1%). For most analyzed groups there was no difference between the diarrhea clinical situation and the intestinal parasite type and number. The multiple intestinal parasite was detected in 12.8% of samples and monoparasitism in 46.5%. The minor age individuals presented the preponderance of protozoan infections / Doutorado / Parasitologia / Doutor em Parasitologia
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Altered Intraerythrocytic Development Phenotypes of Artemisinin-Resistant <i>Plasmodium falciparum</i> Confer a Fitness AdvantageHott, Amanda 01 January 2015 (has links)
Resistance to artemisinin combination therapies (ACTs) has emerged in southeast Asia threatening the most widely used treatment against antimalarial-resistant Plasmodium falciparum worldwide. Artemisinin resistance has been associated with a reduced rate of parasite clearance following treatment with an ACT and is attributed to increased survival of ring-stage parasites. Single nucleotide polymorphisms (SNPs) in kelch gene (K13) has been associated with delayed in vivo clearance half-life of artemisinin-resistant P. falciparum and is the only known molecular marker of resistance. The absence of reliable in vitro phenotypes for artemisinin resistance has limited our understanding of the resistance mechanism(s) and fitness costs, therefore we have culture adapted and cloned patient isolates from Thailand and Cambodia that had clinical resistant phenotypes. Stable reduced susceptibility to artemisinin derivatives and mefloquine was observed using a modified [3H]hypoxanthine drug susceptibility assay. In addition we devised an in vitro phenotype assay of artemisinin resistance, known as the delayed clearance assay (DCA), that was positively correlated with the in vivo delayed clearance and presence of K13 SNPs of artemisinin resistance. Remarkably we discovered for the first time altered patterns of intraerythrocytic development in artemisinin-resistant P. falciparum. In the absence of drug pressure most artemisinin-resistant clones have a prolonged ring phenotype with temporally compressed trophozoite stage, yet with the normal overall asexual life cycle period. Parasites remain in ring-stage up to 14 hours longer than wild-type, whereas time spent in trophozoite-stage is dramatically reduced. One parasite, PL08-09 (5C), exhibited an accelerated 36-hour life cycle in the absence of drug pressure and progressed through asexual development in equal time spent at each intraerythrocytic stage. These data support our hypothesis that parasite resistance to artemisinin results from reduced exposure to drug at the most susceptible stage of development (trophozoite). Interestingly, the most prevalent K13 mutation C580Y is associated with both cell cycle phenotypes. Another cell cycle phenotype, ring-stage dormancy, has been associated with artemisinin resistance in vitro reducing the dormant period of artemisinin-resistant parasites following dihydroartemisinin exposure allowing resistant parasite cultures recrudesce before wild-type. However, sensitive parasites have the ability to enter ring-stage dormancy causing recrudescence in vitro. It is possible that multiple cell cycle phenotypes enhance the survival and fitness of the resistant parasite population as a whole in the face of antimalarial exposure. We have demonstrated that there is a fitness cost associated with artemisinin resistance and remains an important component in the spread of genetic mutations associated with artemisinin resistance. Resistant parasites outcompeted sensitive in vitro only when exposed to dihydroartemisinin. Two mutations associated with artemisinin resistance, including a mutation in K13, were lost in artemisinin resistant parasite by the end of the study. Conversely, parasite cultures maintained artemisinin resistance phenotypes in vitro only if exposed to artemisinin drug pressure every 21-42 days. The mechanism of artemisinin resistance remains elusive and how the parasites alter their intraerythrocytic development is unknown. Therefore. we transfected green fluorescent protein (GFP) or luciferase into artemisinin-resistant P. falciparum clones from Thailand and Cambodia to aid the study the cell cycle phenotypes associated with artemisinin resistance. Artemisinin resistance phenotypes were maintained in stably transfected clones. Increased growth of artemisinin-resistant clones was observed following exposure to ACT partner drug. Low concentrations of antimalarials synchronized the luciferase expression of artemisinin-resistant parasites having different cell cycle phenotypes in the absence of drug pressure. Ring-stage dormancy was observed with many antimalarial drugs and contributes to recrudescence observed by antimalarials other than artemisinin. Our results show evidence that current ACT treatments are selecting multidrug resistant parasites in the field that are better able to tolerate all antimalarials through regulatory cell cycle mechanisms. These cell cycle phenotypes associated with artemisinin resistance contribute to reducing the fitness cost associated with genetic mutations causing artemisinin resistance. This leads to the survival of the most fit population of parasites that survive combination drug treatments, thus demonstrating the importance of discovering novel drugs to target ACT-resistant P. falciparum.
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Sexual selection and sex allocation in the gregarious parasitoid wasp Nasonia vitripennisMoynihan, Anna Margaret January 2012 (has links)
Sex allocation and sexual selection have been heavily studied, but rarely linked. In this thesis I investigated the interface between them in the gregarious parasitoid wasp Nasonia vitripennis, both directly and through their interactions with the mating system and sexual conflict. Chapter 2 investigated sexual selection and mating at the natal site: earlier eclosing males mated more females independently of body size. Nasonia follows Local Mate Competition, which describes how a female laying eggs alone on a patch of resources (a so-called single-foundress) should lay an extremely female-biased brood to minimise competition between her sons, yet ensure all her daughters are fertilised. Based on this I predicted that males with with fewer brothers would be better inseminators. Despite finding significant among-strain variation in (1) single-foundress sex ratio, (2) mate competitiveness when alone and (3) when in competition, (4) sperm resources, but not (5) sperm-depletion (Chapters 3 & 4), I did not find the predicted relationship. Conversely males from strains with more brothers had a higher mating success under competition (Chapter 3) leading to the question: does mating success select on sex ratio or vice versa? Either way it is a result of an interaction between sexual selection and sex allocation. Chapter 5 investigated the role of male post-copulatory courtship on female re-mating, and found that among- strain variation in female re-mating was not associated with variation in the duration of the post-copulatory courtship. Chapter 6 reviewed sexual conflict in the Hymenoptera: their haplodiploid genetics, newly sequenced genomes and varied life- histories provides a base for future research to build on. Finally I highlight the novel links between sexual selection, sex allocation, sexual conflict and the mating system found during my studies that will hopefully prompt future research on this topic.
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Immunomodulatory role of P28GST, a recombinant enzyme from the schistosome helminth parasite in the prevention of experimental colitis / Rôle immunomodulateur de la P28GST, une enzyme recombinant du parasite helminthe Schistosome dans la prévention de la colite expérimentaleEl Nady, Mohamed 17 December 2012 (has links)
Les maladies inflammatoires chroniques de l’intestin font partie des pathologies immunitaires. Leur pathogenèse est directement liée à une réponse immune exagérée dirigée contre des bactéries commensales normalement présentes dans l’intestin, chez des individus génétiquement prédisposés. Parmi les facteurs favorisants, on trouve l’amélioration du niveau d’hygiène ainsi qu’une diminution des infections parasitaires. Des études épidémiologiques ont suggéré une relation entre la prévalence des infections par les helminthes et l’incidence des maladies inflammatoires chroniques de l’intestin dans les pays en développement. Ces infections parasitaires induisant une réponse immune de type Th2, il est donc proposé qu’elles participent la régulation des maladies inflammatoires médiées par une réponse immune de type Th1, comme la maladie de Crohn.Notre équipe s’est intéressée à l’effet immuno-modulateur d’une protéine du Schistosome, la P28GST (Glutathion S-transferase) dont les propriétés immunogénétiques pro-Th2 ont été démontrées précédemment dans des modèles expérimentaux et chez l’homme. Au cours de notre travail, nous avons montré que l’immunisation avec la P28GST était capable de diminuer de manière façon significative la colite expérimentale dans deux modèles animaux. L’immunisation avec cette enzyme parasitaire, produite sous forme recombinante, a réduit les scores cliniques et histologiques obtenus après induction de colite expérimentale par injection de l’haptène TNBS chez des rats Sprague Dawley rats ainsi que chez des souris C57Bl/6. Cet effet est associé à une diminution des marqueurs de l’inflammation (Myéloperoxidase) et de lexpression de l’ARN messager codant pour des cytokines pro-inflammatoires (IL-1β, IL-17 et TNF) dans le colon des animaux. Nous détectons une modulation de la réponse immune caractérisée par une diminution du profil Th1 mesuré par la présence d’ARN messager codant pour l’IFNγ vers un profil de type Th2, associé à une augmentation de l’ARN messager codant pour l’IL-4, l’IL-5 et l’IL-13. L’augmentation du rapport ARN messager Arg1/iNOS2 ainsi que la détection de cellules Arginase positives par immuno-histo chimie dans le colon des animaux immunisés suggèrent la présence de macrophages alternatifs (AAM), dont on connait le rôle anti-inflammatoire et l’association à une réponse de type Th2. Des résultats similaires ont été obtenus dans un autre modèle expérimental, chez la souris.Nous avons comparé l’effet de cette protéine du Schistosome avec l’effet de l’infection par des larves du parasite grâce à deux modèles d’infection : soit une infection au long cours (associé avec une réponse immune de type Th2), soit une infection récente (avec une réponse immune de type Th1). Nos résultats montrent que l’immunisation par une seule protéine de schistosome, la P28GST, réduit l’inflammation intestinale aussi bien que l’infection au long cours, tandis que les animaux récemment infectés n’étaient pas protégés de la colite. En conclusion, notre étude présente les premières évidences que l’immunisation avec une protéine recombinante de Schistosome pourrait réduire de manière préventive la colite expérimentale induite par l’injection d’une haptène dans deux modèles de rongeurs. Si les mécanismes d’action précis doivent encore être élucidés, nos travaux suggèrent que l’effet anti-inflammatoire de la P28 GST puisse avoir des applications dans la prévention de l’inflammation intestinale permettant d’envisager une utilisation chez l’homme, notamment dans la prévention des rechutes de la maladie de Crohn. / Inflammatory bowel diseases are considered part of immune-mediated inflammatory disorders. Their pathogenesis was linked to an inappropriate exaggerated immune response to commensal bacteria normally present in the bowel, in genetically predisposed individuals. Increase of the level of hygiene and decrease exposure to helminthic infections was suggested as predisposing factors to IBD. Epidemiologic data have given a clue on the relation of prevalence of helminthic infections and the incidence of inflammatory bowel diseases in developing countries. The Th2 polarized T cell response driven by helminthic infection has been linked to the attenuation of Th1 driven inflammatory responses, preventing some Th1 mediated autoimmune diseases in their host, including Crohn’s disease.Our work focused on the immuno-modulatory effect of a Schistosome protein – P28GST (a Glutathion S-transferase). Its immuno-genetique, pro-Th2, characters have been previously demonstrated in experimental models as well as clinical trials. We showed that immunization with P28GST was able to significantly reduce experimentally induced colitis in two animal models.Immunisation with this recombinant parasitic enzyme reduced clinical and histological scores of the TNBS induced colitis in both Sprague Dawley rats as well as in C57Bl/6 mice. This effect was associated with a decrease in the expression of inflammatory markers (Myeloperoxidase) as well as mRNA expression of pro-inflammatory cytokines (IL-1β, IL-17 and TNF) in the colon of sacrificed animals. We detected a shift of the immune response characterized with decrease of Th1 immune response assessed by the mRNA expression of IFNγ towards a less pathological Th2 immune response assessed by the mRNA expression of IL-4, IL-5 and IL-13. An increase in the ratio of mRNA expression of Arg1/iNOS2, as well as the immuno-histochemical detection of Arginase positive cells in the colon of the sacrificed animals suggested the presence of alternatively activated macrophages (AAMs) characterized by their anti-inflammatory effect and their association with the Th2 immune response. Similar results have been obtained in another animal model, the C57Bl/6 mice.We have also compared the effect of a single recombinant Schistosome protein to two models of infection with living schistosome parasites, either with long standing infection (associated with a Th2-type response) or with a recent onset exposure (a Th1-type response). Our results showed that immunisation with a single Schistosome protein, the P28GST; give similar results to established infection in term of reduction of intestinal inflammation, whereas recently infected rats were not protected against colitis.In conclusion, this study provides the first evidence that immunization with a recombinant protein from the Schistosome helminth parasite prevents hapten-induced colitis in two models of rodents. Although further studies are needed to illustrate the exact mechanisms of action implicated in the immuno-modulatory effect, P28GST is a promising molecule exerting a potent anti-inflammatory role in the prevention of colitis. The potential effect of this helminthic enzyme is actually taken in consideration in the prevention of Crohn’s disease relapses in humans.
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Distribution of Parasitic Isopods on Caridean Shrimp in South Florida Seagrass BedsBriggs, Sarah A. 01 July 2013 (has links)
Caridean shrimp are a prominent element of seagrass faunal communities and play an important role in the energy transfer between trophic levels. They are a food source for other organisms and play an integral role in the ecosystem by feeding on algae and assisting with the breakdown of organic matter. Carideans are also fundamental to the marine fishery industry in that they are a food source for potentially valuable juvenile commercial fish. Ectoparasitic isopods (Cymothoida: Bopyridae) that infest caridean shrimps decrease the energy level of the shrimp, resulting in slower reaction time, greater predation rate, slower growth rate, and/or reduced egg production. However, in South Florida, little is known about the distributions and effects of parasitism among caridean shrimp in seagrass habitats. This research investigates the relationship of caridean shrimps and ectoparasitic isopods throughout several marine and brackish basins of coastal South Florida ranging from Lostmans River on the lower southwest mangrove coast through Florida Bay and Biscayne Bay. Samples were collected at the end of the wet season in 2010 and the dry season in 2011 using a 1-m2 throw-trap. Relations among isopods, carideans and environment were determined based on a series of biotic (host preference and availability) and abiotic (salinity, temperature, turbidity, water depth) factors. Bopyrid isopods were most abundant in Manatee Bay and Barnes Sound adjacent to the C-111 canal located in southern Biscayne Bay region and predominantly associated with Hippolyte spp. Logistical regression revealed that the likelihood of parasite presence is associated with higher temperatures, lower salinity, increasing depth, less seagrass coverage and greater macroalgae coverage. The results suggest that increased stressors in an environment, such as anthropogenic runoff, may also negatively impact host resistance to parasitism.
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Communautés de nématodes phytoparasites associés à l'olivier : réponse aux forçages anthropiques et environnementaux / Plant-parasitic nematodes communities associated to olive trees : response to anthropogenic environmental and forcingsAli, Nadine 08 October 2015 (has links)
Les interventions humaines de plus en plus fréquentes et persistantes dans les écosystèmes d'une part, et l'intensification des systèmes de cultures d'autre part qui s'accompagne pour partie de méthodes radicales pour combattre les bio-agresseurs des cultures, nous posent de multiples questions au sujet des risques écologiques liés aux changements des milieux, dont les perturbations induites sur les communautés d'organismes vivants. Les nématodes phytoparasites (NPP), vers ronds microscopiques telluriques qui occasionnent des pertes de production végétale importantes, sont partout présents en communautés. Ces nématodes répondent rapidement aux forçages extérieurs (e.g. anthropiques et environnementaux) par des modifications de la structure de leurs communautés. Par ce travail de thèse, nous cherchons à mieux comprendre l'effet des facteurs impliqués dans l'assemblage des espèces de NPP en communautés associées à l'olivier méditerranéen et à déterminer la réponse de ces communautés aux forçages imposés par la domestication de l'olivier, par l'intensification de sa culture et par différents facteurs environnementaux. L'étude a été réalisée au Maroc dans toutes les régions oléicoles (vergers traditionnels à faible densité et vergers à haute-densité), dans les zones refuge d'olivier sauvage (oléastre) et sur olivier féral. Les facteurs pédoclimatiques qui caractérisent les sites d'échantillonnage ont également été pris en considération. L'analyse de la nématofaune a révélé d'une grande diversité spécifique, de nombreuses espèces étant décrites pour la première fois sur olivier, et une nouvelle espèce (Meloidogyne spartelensis) ayant été découverte. La diversité, la composition taxonomique, trophique et fonctionnelle, la dominance des taxons, les patrons de communautés sont fortement affectés par les différents forçages pris en compte. Le gradient d'anthropisation croissante (sauvage vs féral vs cultivé traditionnel vs cultivé haute-densité) est la variable qui impacte le plus la diversité par réduction de la richesse spécifique et l'augmentation de l'abondance en NPP. L'étude a également porté une attention particulière sur la diversité des nématodes à galles des racines du genre Meloidogyne, un des principaux ravageurs de l'olivier. Elle a indiqué la dispersion de M. javanica dans les vergers et sur olivier féral, alors que d'autres espèces (M. arenaria, M. hapla et M. spartelensis) sont confinées dans les zones refuge des oléastres. Afin d'analyser la diversité génétique, des marqueurs morphologiques et moléculaires ont dévoilé d'une diversité importante entre et au sein des différentes populations de Meloidogyne. Les études diligentées dans le cadre de cette thèse confirment que la diversité et la structure des communautés de NPP pourraient être des indicateurs pertinents pour évaluer la santé des sols dans les agro et écosystèmes, en corrélant diversité et pathogénicité des communautés. Elles soulignent donc l'importance de la diversité parasitaire comme variable prioritaire à prendre en compte pour inspirer des stratégies de gestion des parasites basées sur le concept de résilience de la diversité (même s'il s'agit de parasites), pour une gestion durable des communautés de NPP et la préservation des milieux. / Human activities increasingly frequent and persistent in ecosystems on one hand, and cropping system intensification on the other hand partly with radical methods to control pests and diseases of crops, raise questions about the ecological risks related to biotop changes, including disturbances of living organism communities. Plant-parasitic nematodes (PPN), microscopic round soil-borne worms that cause significant losses of crop production, are everywhere present in communities. They respond quickly to external forces (e.g. human and environmental) by changing the structure of their communities. In this thesis, we seek to better understand the effect of the factors involved in the assemblage of PPN species in communities associated with the Mediterranean olive tree and to determine the response of these communities to forces imposed by olive domestication, by crop intensification and by various environmental factors. The study was conducted in all olive-growing regions in Morocco (traditional low density and high density orchards), in refugia areas for wild olive (oleaster) and on feral olive trees. The soil and climatic factors that characterize the sampling sites were also considered. The analysis of the nematofauna revealed a wide species diversity, many species being described for the first time on olive tree, and a new species (Meloidogyne spartelensis) have been discovered. The diversity, the species / trophic / functional structure of the communities, the dominance of the taxa, and the community patterns are strongly affected by the various forces considered. The increasing anthropogenic gradient (wild vs feral vs traditional cultivation vs high-density cultivation) is the variable that mostly impacts the diversity by reducing the species richness and increasing the abundance of PPN. A particular attention was attributed in this study to the diversity of root-knot nematodes Meloidogyne, a major pest of the olive tree. It revealed that M. javanica is widespread in orchards and olive feral, while other species (M. arenaria, M. hapla and M. spartelensis) are confined in oleaster refuge areas. In order to analyse the genetic diversity, morphological and molecular markers have revealed a significant diversity between and within different Meloidogyne populations. These thesis studies confirm that both the diversity and the structure of the PPN communities could be relevant indicators to assess soil health in agro and ecosystems, by correlating diversity and pathogenicity of communities. They therefore emphasize the importance of parasite diversity as a main variable to consider for inspiring pest control strategies based on the concept of diversity resilience (even if it concerns parasites) for sustainable management of PPN communities and for environment preservation.
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A step forward in defining Hsp90s as potential drug targets for human parasitic diseasesFaya, Ngonidzashe January 2014 (has links)
Parasitic diseases remain a health burden affecting more than 500 million people worldwide with malaria having the highest mortality rate. The parasites can be transferred to the human bodies either through the mouth by ingestion of contaminated food and water or through the skin by bug bites or direct contact to environments harbouring them. Epidemiological control seems to be impossible since there is failure to control the insect vectors as well as practice of hygiene. Therefore, this has led to the development of a number of vaccines, chemotherapy and disease control programs. However, parasites have increasingly developed resistance to traditionally used anti-parasitic drugs and due to that fact there is need for alternative medication for parasitic diseases. Heat shock protein 90 (Hsp90) facilitates the folding of proteins in all living cells and their role is more important to parasites because of their environmental changes, from vector to host. Hsp90s play a major role; therefore this justifies the need for a deeper analysis of the parasitic Hsp90s. Recent studies have revealed that, the Plasmodium sp. Hsp90 has an extended linker region which increases the protein’s affinity for ATP and its inhibitors. Therefore we hypothesize that there are also significant features in other parasitic Hsp90s which would lead to Hsp90 being defined as potential drug targets. In the present study an attempt was made to gain more insight into the differences in primary structure of human and parasitic Hsp90s. The sequences were retrieved from the NCBI database and analysis was done in three groups basing on the localization of the Hsp90. The physicochemical properties were calculated and in every group, the protozoan Hsp90s showed significant differences when compared to the human orthologs. Multiple sequence alignments (MSA) showed that endoplasmic reticulum Hsp90s have an extended region in the middle domain indicating their ability to bind to a unique subset of client proteins. Sequence identities between the human and parasites showed that the protozoan Hsp90s are less related to the human Hsp90s as compared to the other parasites. Likewise, motif analysis showed the trypanosomatids and apicomplexan groups have their own unique set of motifs and they were grouped together in the phylogenetic analysis. Phylogenetic analysis also showed that, the protozoan Hsp90s forms their own clades in each group while the helminths did not form in endoplasmic reticulum group. In this study, we concluded that, Hsp90 can be a potential drug target for the protozoan species and more specifically those from the apicomplexan and trypanosomatids groups.
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Capacitação por ensino à distância de agentes de saúde na prevenção de doenças parasitárias / Capacity for distance learning agents of health in the prevention of parasitic diseasesFerreira, Glauco Rogério, 1973- 22 August 2018 (has links)
Orientador: Ana Maria Aparecida Guaraldo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T08:35:35Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: A Organização das Nações Unidas (ONU) no ano 2000 definiu oito Objetivos do Milênio; dentre eles pode-se destacar o sexto que é Combater o HIV/AIDS, a malária e outras doenças. As doenças parasitárias constituem ainda um sério problema de saúde pública. A erradicação ou controle desses parasitas requer melhorias das condições sócio-econômicas, do saneamento básico e educação. O presente trabalho teve como objetivo avaliar o Ensino a Distância como ferramenta de ensino para agentes de saúde, sobre as temáticas Doenças parasitárias; Criar conteúdo e disseminar conhecimento para capacitar agentes municipais de saúde em medidas profiláticas, transmissão e prevenção de parasitoses intestinais, através do preparo e aplicação de curso a distância (EAD); Analisar a Plataforma TelEduc para difundir essa capacitação a outros agentes. O curso foi montado e realizado em Plataforma TeldEduc, hospedada no Instituto IPES (Instituto de Projetos Especiais), com duração de 180 horas, sendo 148 horas por EAD e 32 presenciais. A maioria das aulas presenciais foi realizada na Faculdade Municipal "Professor Franco Montoro", no município de Mogi Guaçu-SP. O público alvo foi constituído pelos agentes de saúde e profissionais da saúde; 158 alunos se inscreveram no curso e a taxa de evasão foi de 24,8%. As aulas presenciais eram constituídas por aulas práticas, visitas técnicas ou revisão de conteúdo. Foi aplicado um questionário no início e outro no término para avaliar os conhecimentos pré existentes sobre a temática e os adquiridos pelo curso. Foi empregado o teste Qui-Quadrado para avaliar o nível de significância entre as respostas dos questionários. Concluiu-se que o EAD pode e deve ser utilizado, como uma alternativa de educação em doenças parasitárias, como mais uma ferramenta útil para acesso e ampliação do conhecimento / Abstract: The Organization of the United Nations (ONU) in 2000 set eight Millennium Development Goals; among them we can highlight which is the sixth: Combat HIV / AIDS, malaria and other diseases. Parasitic diseases are still a serious public health problem. The eradication or control these parasites requires improvements in socioeconomic conditions, sanitation and education. This study aimed to evaluate the Distance Learning as a teaching tool for health workers, concerning parasitic diseases. Create content and disseminate knowledge to empower local health agents in prophylactic measures, transmission and prevention of intestinal parasites, through the preparation and application of distance learning course (DLC); Analyze Platform TelEduc to disseminate this training to other agents. The course was set up and held in TeldEduc Platform, hosted at the Institute IPES, lasting 180 hours, with 148 hours of classroom and 32 DLC. Most regular classes were held in the Faculty Franco Montoro. The course was facing health workers and health professionals, 158 people enrolled in the course and 115 completed, which generated a dropout rate of 24,8%. The classroom consisted of practical sessions, technical visits or content review. A questionnaire was applied at the beginning and another at the end to assess the pre-existing knowledge on the subject and acquired by the course. It was employed a chi-square test to assess the level of significance between the answers of questionnaire. It was concluded that the DLC can and should be used as an alternative education on parasitic diseases and means a very useful tool to improve the access and knowledge / Doutorado / Relações Antrópicas, Meio Ambiente e Parasitologia / Doutor em Biologia Animal
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Caracterização e padronização de marcadores genéticos para o estudo de polimorfismos em Plasmodium vivax. / Characterization and standardization of genetic markers in the study of Plasmodium vivax polymorphisms.Michelle Cristina do Couto Brandi 24 May 2013 (has links)
Este trabalho teve como objetivo caracterizar e padronizar métodos para a tipagem molecular de marcadores genéticos, para futuro uso em estudos de genética populacional de Plasmodium vivax na Amazônia brasileira. As amostras sanguíneas utilizadas neste estudo foram colhidas no Brasil, Camboja, Sri Lanka e Estados Unidos. Foram selecionados polimorfismos de única base (SNPs) distribuídos ao longo de cromossomos distintos de P. vivax; para estes polimorfismos, sete ensaios de tipagem de SNPs foram padronizados com sucesso. Com a tipagem molecular, foi possível definir haplótipos que caracterizam cada amostra, assim como identificar infecções geneticamente mistas (co-ocorrência de clones distintos na mesma amostra). No entanto, com este conjunto de marcadores não foi possível agrupar amostras de acordo com sua localização geográfica, por estes marcadores não serem suficientemente informativos do ponto de vista genético. Os sete SNPs avaliados, quando comparados a 13 marcadores de DNA microssatélite, revelaram menor proporção de infecções geneticamente mistas e menor diversidade genética. / This study aimed to characterize and standardize methods for molecular typing of genetic markers to be used in the future in studies of population genetics of Plasmodium vivax population in the Brazilian Amazon. Blood samples used in this study were collected in Brazil, Cambodia, Sri Lanka and United States. Single nucleotide polymorphisms (SNPs), distributed over different P. vivax chromosomes were chosen and seven typing assays were sucessfully standardized. Molecular typing of polymorphisms allowed to define haplotypes that characterize each sample, as well as to identify genetically mixed infections (co-occurrence of different clones in the same sample). However, with this markers set, it was not possible to group samples according to their geographical location, because probably they are not sufficiently genetically informative. Compared to 13 microsatellite markers, these seven SNPs revealed a lower proportion of mixed-clone infections and lower genetic diversity.
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