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1
Giles, Michaela. "Host specificity and molecular detection of Cryptosporidium hominis and Cryptosporidium parvum". Thesis, London School of Hygiene and Tropical Medicine (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433502.
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Benamrouz, Sadia. "Infection par Cryptosporidium spp. du modèle souris SCID traité à la dexaméthasone : caractérisation cellulaire et moléculaire du processus de cancérisation des épithéliums digestifs". Thesis, Lille 2, 2012. http://www.theses.fr/2012LIL2S040/document.
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Au vu des travaux de Certad et de ses collaborateurs, nous savons que Cryptosporidium parvum est également capable d’induire des adénomes avec des néoplasies digestives intraépithéliales de bas grade et de haut grade, ainsi que des adénocarcinomes in situ, chez des souris SCID (Severe Combined Immunodeficiency) déficientes en lymphocytes T et B, traitées par la dexaméthasone (SCID-D). De plus, nous savons aussi que Cryptosporidium muris induit une infection chronique mais pas de lésions néoplasiques. C’est pour faire suite à ces observations que nous avons entrepris dans un premier temps de déterminer la dose minimale de Cryptosporidium parvum (souche IOWA d’origine animale) pouvant infecter ce modèle et induire des néoplasies digestives. Nous avons montré qu’une dose très faible de parasites (théoriquement 1 oocyste) est capable d’induire non seulement une infection chronique chez les souris (SCID-D) mais également l’apparition de lésions néoplasiques aussi bien dans la région antropylorique de l’estomac qu’au niveau de la région iléo-caecale et cela dès 45 jours post infection. Nous avons également suivi la progression de ces lésions à la suite d’infection des souris par plusieurs doses de C. parvum (souche IOWA) (théoriquement : 1, 10, 100 et 105 oocystes). Ce travail a également été réalisé après inoculation d’une souche de C. parvum d’origine humaine (isolée à partir d’un patient immunodeprimée soufrant d’une cryptosporidiose grave à la suite d’une noyade). Pour cela, nous avons réalisé un suivi prolongé des animaux (au delà de 84 jours) et des analyses histopathologiques associées à la détection immuno-histochimique de la cytokeratine et de l’alpha actine lisse. Il a été observé, avec toutes les doses et pour les deux souches, aussi bien dans la région antropylorique qu’iléo-caecale des animaux, la présence d’adénomes contenant un grand nombre de parasites. Nous avons noté pour la première fois au niveau de ces lésions néoplasiques la présence d’une desmoplasie et de bourgeons de cellules tumorales envahissant le chorion de la muqueuse. En plus de ces éléments histologiques caractéristiques des adénocarcinomes invasifs, les différentes colorations et marquages ont mis en évidence d’autres signes d’invasion: une membrane basale discontinue, la présence de cellules épithéliales au niveau du stroma et enfin une interruption de la muscularis mucosa, voire une invasion de la musculeuse. Dans un deuxième temps, nous nous sommes intéressés aux voies de cancérogénèse impliquées dans le processus d’induction des lésions néoplasiques par C. parvum (IOWA) au niveau de la région iléocæcale. Afin d’initier nos travaux dans cette perspective, nous avons choisi quatre marqueurs impliqués dans les principales voies altérées dans les cancers colorectaux: APC, Beta-catenine, P53 et K-ras. Des études immunohistochimiques ont été réalisées et nous ont permis de noter qu’il y avait une localisation anormale aussi bien de l’APC, que de la Beta-catenine ou de la P53. La Beta-catenine (normalement localisée au niveau de la membrane cellulaire) et la P53 (normalement localisée dans le noyau) s’accumulent dans le cytoplasme alors que le marquage de l’APC dans les cellules néoplasiques diminue, voire même disparait. Le marquage de K-ras, quant à lui, est toujours membranaire comme dans les cellules normales. Tout cela semble indiquer l’implication des voies P53 et Wnt dans le phénomène de cancérogénèse chez notre modèle de souris (SCID-D). Des études visant à rechercher d’autres marqueurs et d’éventuelles mutations des gènes codant ces protéines sont en coursCertad and col, showed recently that Cryptosporidium parvum is also capable of inducing gastrointestinal adenomas with intraepithelial neoplasia of low and high grade, and adenocarcinomas in situ in SCID mice (Severe Combined immunodeficiency), treated with dexamethasone (SCID-D). In addition, we also know that Cryptosporidium muris induces a chronic infection but no neoplastic lesions.This is why we decided first to determine the minimum dose of C. parvum (IOWA) which can infect and cause digestive neoplasia in this model. This work allowed us to conclude that one oocyst is able to induce in SCID-D mice not only a chronic infection but also the development of neoplastic lesions in both the antropyloric region of the stomach and the ileocecal region at 45 days post infection. We also followed up the progression of these lesions after infection with several doses of C. parvum strain IOWA (theoretically: 1, 10, 100 and 105 oocysts). This work was also performed after inoculation of another strain of different origin isolated from an immunosupressed patient suffering from a severe cryptosporidiosis after a near-drowning). To do this we have achieved: an extended follow-up of animals (over 84 days) and an histopathological analysis based on immunohistochemical detection of cytokeratin and alpha smooth actin. For the first time it was noted with all doses and for the two strains, in both the antropyloric and ileocecal region of animals, a patern characteristic of invasif adenocarcinoma: desmoplasia and buds of tumor cells invading the lamina propria. In addition to these histological features, a discontinuous basement membrane, the presence of epithelial cells in the stroma, an interruption of the muscularis mucosa and an invasion of the muscularis were also detected. In the case of the strain of C. parvum of human origin, the adenocarcinoma also invaded the serosa and epithelial cells were observed inside blood vessels (vascular tumor emboli). Lesion’s progression was so fast that after only 60 days post-infection we observed at least, the invasion of the submucosa at ileocecal region. Furthermore, the results of this study showed for the first time the ability of an isolate of C. parvum of human origin to cause chologiocarcinoma in an experimental model. Finally, using an immunohistochemical approach, we explored metabolic pathways involved in the development of C. parvum-induced neoplastic lesions at the ileocecal region. Four markers involved in major pathways altered in colorectal cancer were chosen: APC, beta-catenin, p53 and K-ras. The assesment of tumor marker expression in the ileocaecal area showed an abnormal localization of APC, beta-catenin and p53. Beta-catenin and p53 accumulated in the cytoplasm, while APC labelling decreased or even disappeared. Meanwhile, K-ras was still at membrane level as in normal cells. these results suggest the involvement of p53 and Wnt pathway in the phenomenon of carcinogenesis in our mouse model (SCID-D). Studies to search the implication of other markers and possible mutations of the genes encoding these proteins are underway. In conclusion,, these findings show that different strains of C. parvum including a strain of human origin induce digestif invasive adenocarcinomas whatever the inoculum size administered to SCID-D mice. These results confirm the role of C. parvum in the induction of digestive cancer in immunocompromised hosts. In addition, the pathways involved in the process of carcinogenesis in mice (SCID-D) appeared to be the same as those altered in humans. Moreover, the Wnt signaling pathway in which the actin polymerization and rearrangement of the cytoskeleton are involved is a major event during Cryptosporidium infection and appears to play a role in the carcinogenic process induced by the parasite
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Siddiki, Amam Zonaed. "Proteome analysis of Cryptosporidium". Thesis, University of Liverpool, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428228.
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Arrowood, Michael James. "Cryptosporidium: Oocyst production and hybridoma generation for examining colostrum and monoclonal antibody roles in cryptosporidial infections". Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184335.
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Techniques for the large-scale isolation of Cryptosporidium oocysts and sporozoites, obtained from the feces of experimentally infected Holstein calves, were developed employing discontinuous sucrose gradients and isopycnic Percoll gradients. The three step oocyst recovery method utilized two sequential discontinuous sucrose gradients followed by one Percoll gradient. Recovered oocysts were essentially free of debris and bacteria and represented 34% of the original oocyst suspension. Sporozoites were recovered from excystation mixtures on a single Percoll gradient. Sixty-three percent of the original sporozoites were recovered with 2.2% contamination by intact oocysts and virtually no oocyst walls. Eight anti-oocyst hybridomas were derived from oocyst-immunized mice: five from BALB/c mice and three from RBF/Dn mice. The monoclonal antibody (Mab) OW3 reacted specifically with C. parvum oocysts in immunofluorescent assays (IFA) and was shown to be superior to conventional stains for detecting oocysts in fecal smears from infected individuals. Sixteen anti-sporozoite hybridomas were derived from sporozoite-immunized BALB/c mice. The Mabs appeared to react with cell surface and cytoplasmic antigens by IFA. Two anti-sporozoite Mabs (C8C5, C6B6) reacted with a 20 kDa sporozoite antigen in western blots while the Mab C4A1 reacted with multiple antigens in western blots. These three Mabs (C8C5, C6B6, C4A1) were examined for potential modulation of cryptosporidial infections in vivo by oral Mab administration to oocyst-inoculated neonatal mice. The role for colostrum and breast milk in controlling cryptosporidial infections was examined by immunizing mouse dams and experimentally infecting their neonatal offspring. Colostrum and Mab-treated neonatal mice were sacrificed four days post infection. No difference in infection rates was observed among the treatment groups. Suckling mice treated daily with orally administered mixtures of Mabs (purified or ascitic fluid) showed significantly reduced parasite loads compared to control mice at four days post infection. In vitro cultivation of C. parvum was successful through asexual stages in human fetal lung, bovine turbinate and murine L929 cells. Parasite numbers that developed in the cell cultures varied from infection run to infection run.
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Pollok, Richard. "Cryptosporidium parvum : host-parasite interactions". Thesis, Queen Mary, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402442.
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Buaprathoom, Somporn. "Photonics based cryptosporidium detection systems". Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580330.
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Cryptosporidium is a protozoan parasite causing cryptosporidiosis; a diarrheal disease of varying severity. The infection is transmitted by tiny spores called oocysts resistant to harsh environmental conditions and various disinfectants. Cryptosporidium infection and recovery from the illness is dependent on the body's immune system. It is important to be able to detect these parasites quickly to reduce the risk of infection. Multiple-angle light scattering systems have been developed for detecting cryptosporidium oocysts suspended in water. The proposed systems were set up with a single wavelength (red AlGaInP laser: 658.4 nm) and two wavelength (violet InGaN laser: 405.7 nm and red AlGalnP laser: 658.4 nm) sources. The single wavelength system was developed for measuring particle concentration and particle size and refractive index. It combined multiple-angle scattering detection, to collect angle- resolved scattered intensities from suspensions, and the partial least square regression method (PLS-R) to predict characterizing information of samples under investigation based on calibration models. The calibration models were composed from the calibration data generated from the experiments for particle concentration measurement and according to Mie theory with refraction and transmission corrections included for particles' size and refractive index measurements. The dual wavelength system was set up for particle identification by using relative wavelength scattered intensity as the identifying means. Measurement of particle concentration, size and refractive index by the single multiple angle light scattering system was validated using polystyrene spheres in aqueous suspensions. Applying the systems to cryptosporidium oocyst suspensions, the concentration measurement results had lowest errors from the references 9.5 % at concentration of 2.00x10600cysts/ml in mono-dispersion and 3.6 % at concentration of 7.50x105 oocysts/ml for cryptosporidium and mixed suspensions with polystyrene sphere suspensions. The measured cryptosporidium oocysts' size and refractive index were 4.37 ± 0.16!-Lm and 1.38 ± 0.05 which also had good agreement to the reference value (size: 4.38 ± 0.23 urn, refractive index: 1.37). The dual wavelength multiple-angle light scattering system collected the relative wavelength scattered intensities from suspensions of the cryptosporidium oocysts comparing to polystyrene spheres and E.coli. The relative wavelength multiple-angle scattered intensity of cryptosporidium oocysts suspension showed a characteristic scattering pattern and significantly different pattern from the polystyrene spheres and bacteria E.coli. The results presented in this research have demonstrated that the proposed multiple-angle light scattering systems have the capability to initially detect cryptosporidium oocysts in suspension. These systems could be further developed for online cryptosporidium detection by combination with pattern recognition techniques.
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Silva, Deuvânia Carvalho da [UNESP]. "Avaliação física, epidemiológica e molecular da infecção por Cryptosporidium spp. em passeriformes". Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/94711.
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Devido à carência de informações relacionadas à epidemiologia da infecção por Cryptosporidium spp. em passeriformes, neste trabalho objetivou-se determinar a periodicidade da eliminação fecal de oocistos de Cryptosporidium, os sinais clínicos, a presença de mortalidade, e a caracterização molecular desse coccídio. Foram colhidas 480 amostras de fezes, provenientes de 40 aves, sendo 372 amostras de 31 aves adultas e 108 amostras de nove filhotes até 12 semanas de vida, com periodicidade mensal, no período de setembro de 2007 a setembro de 2008, com exceção do mês de abril. As aves estavam alojadas em cinco criatórios, com criação de bicudo (Oryzoborus maximiliani), curió (Oryzoborus angolensis), azulão (Passerina brissonii) e coleira do brejo (Sporophila collaris). As amostras foram conservadas em bicromato de potássio 2,5%, a 4ºC, até o processamento. Os oocistos foram purificados por centrífugo-flutuação em solução de Sheather, seguindo-se a extração do DNA genômico dos oocistos e a classificação molecular, por meio da reação em cadeia de polimerase-nested, para amplificação de fragmentos da subunidade 18S do gene do RNA ribossômico. Eliminação fecal intermitente de Cryptosporidium spp. foi observada em 91 (24,5%) amostras de aves adultas, com maior ocorrência nos períodos que se aproximam dos períodos de muda de penas e de reprodução das aves e em 14 amostras (13%) de aves jovens. O sequenciamento dos fragmentos de DNA amplificados possibilitou a identificação de somente Cryptosporidium galli. Embora em todos os criatórios houvesse aves positivas para C. galli, a presença de morbidade ou mortalidade foi observada em aves de somente um criatório, e estava associada à infecção concomitante com Escherichia coli e Isospora spp..Este é o primeiro relato de infecção por C. galli em P. brissonii, O. maximiliani e S. collaris
Due to the lack of information related to the epidemiology of Cryptosporidium infection in passerine birds, this study aimed to determine the frequency of fecal shedding of Cryptosporidium spp. oocysts, after natural infection, the clinical signs and the presence of mortality, and accomplish its molecular characterization. Four hundred and eighty fecal samples were collected from 40 birds, 372 samples from 31 adult birds and 108 samples from young birds (up to 12 months old), housed in five herds, monthly, from September 2007 to September 2008, with the exception of the April. The birds were originated from flocks were the following species were herd: great-billed seed-finch (Oryzoborus maximiliani), lesser seed-finch (Oryzoborus angolensis), ultramarine grosbeak (Passerina brissonii) and rusty-collared seedeater (Sporophila collaris). The samples were preserved in 2.5% potassium dichromate 2.5% at 4°C, until processing. The oocysts were purified by centrifugal flotation in Sheather solution, followed by genomic DNA extraction from oocysts and molecular characterization using the nested polymerase chain reaction for amplification of fragments of the 18S subunit ribosomal RNA gene. Intermittent fecal shedding of Cryptosporidium spp. was observed in 91 (24.5%) samples from adult birds, with more frequent in periods approaching the periods of moulting and reproduction of birds and 14 samples (13%) of young birds.The sequencing of the amplified fragments allowed the identification of Cryptosporidium galli. Although all the aviaries had birds positive for C. galli, morbidity or mortality was observed in birds from only one aviary, and was associated to concomitant infection with Escherichia coli and Isospora sp. This is the first report of infection by C. galli in Oryzoborus maximiliani, Passerina brissonii, and Sporophila collaris
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Silva, Deuvânia Carvalho da. "Avaliação física, epidemiológica e molecular da infecção por Cryptosporidium spp. em passeriformes /". Araçatuba : [s.n.], 2009. http://hdl.handle.net/11449/94711.
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Orientador: Marcelo Vasconcelos MeirelesBanca: Valéria Marçal Félix de Lima
Banca: Rodrigo Martins Soares
Resumo: Devido à carência de informações relacionadas à epidemiologia da infecção por Cryptosporidium spp. em passeriformes, neste trabalho objetivou-se determinar a periodicidade da eliminação fecal de oocistos de Cryptosporidium, os sinais clínicos, a presença de mortalidade, e a caracterização molecular desse coccídio. Foram colhidas 480 amostras de fezes, provenientes de 40 aves, sendo 372 amostras de 31 aves adultas e 108 amostras de nove filhotes até 12 semanas de vida, com periodicidade mensal, no período de setembro de 2007 a setembro de 2008, com exceção do mês de abril. As aves estavam alojadas em cinco criatórios, com criação de bicudo (Oryzoborus maximiliani), curió (Oryzoborus angolensis), azulão (Passerina brissonii) e coleira do brejo (Sporophila collaris). As amostras foram conservadas em bicromato de potássio 2,5%, a 4ºC, até o processamento. Os oocistos foram purificados por centrífugo-flutuação em solução de Sheather, seguindo-se a extração do DNA genômico dos oocistos e a classificação molecular, por meio da reação em cadeia de polimerase-nested, para amplificação de fragmentos da subunidade 18S do gene do RNA ribossômico. Eliminação fecal intermitente de Cryptosporidium spp. foi observada em 91 (24,5%) amostras de aves adultas, com maior ocorrência nos períodos que se aproximam dos períodos de muda de penas e de reprodução das aves e em 14 amostras (13%) de aves jovens. O sequenciamento dos fragmentos de DNA amplificados possibilitou a identificação de somente Cryptosporidium galli. Embora em todos os criatórios houvesse aves positivas para C. galli, a presença de morbidade ou mortalidade foi observada em aves de somente um criatório, e estava associada à infecção concomitante com Escherichia coli e Isospora spp..Este é o primeiro relato de infecção por C. galli em P. brissonii, O. maximiliani e S. collaris
Abstract: Due to the lack of information related to the epidemiology of Cryptosporidium infection in passerine birds, this study aimed to determine the frequency of fecal shedding of Cryptosporidium spp. oocysts, after natural infection, the clinical signs and the presence of mortality, and accomplish its molecular characterization. Four hundred and eighty fecal samples were collected from 40 birds, 372 samples from 31 adult birds and 108 samples from young birds (up to 12 months old), housed in five herds, monthly, from September 2007 to September 2008, with the exception of the April. The birds were originated from flocks were the following species were herd: great-billed seed-finch (Oryzoborus maximiliani), lesser seed-finch (Oryzoborus angolensis), ultramarine grosbeak (Passerina brissonii) and rusty-collared seedeater (Sporophila collaris). The samples were preserved in 2.5% potassium dichromate 2.5% at 4°C, until processing. The oocysts were purified by centrifugal flotation in Sheather solution, followed by genomic DNA extraction from oocysts and molecular characterization using the nested polymerase chain reaction for amplification of fragments of the 18S subunit ribosomal RNA gene. Intermittent fecal shedding of Cryptosporidium spp. was observed in 91 (24.5%) samples from adult birds, with more frequent in periods approaching the periods of moulting and reproduction of birds and 14 samples (13%) of young birds.The sequencing of the amplified fragments allowed the identification of Cryptosporidium galli. Although all the aviaries had birds positive for C. galli, morbidity or mortality was observed in birds from only one aviary, and was associated to concomitant infection with Escherichia coli and Isospora sp. This is the first report of infection by C. galli in Oryzoborus maximiliani, Passerina brissonii, and Sporophila collaris
Mestre
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Miller, Woutrina Ann. "Cryptosporidium species in coastal California ecosystems /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.
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Ghaffari, Salman. "A genotyping study of Cryptosporidium species". Thesis, University of Liverpool, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425447.
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Edwards, Hanna. "The 100 Faces of Cryptosporidium parvum". Thesis, Edwards, Hanna (2012) The 100 Faces of Cryptosporidium parvum. PhD thesis, Murdoch University, 2012. https://researchrepository.murdoch.edu.au/id/eprint/10792/.
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Cryptosporidium parvum is a protozoan enteric parasite of humans and livestock. C. parvum infection mainly affects the ileum, where it has the potential to cause severe enteric disease. Drugs for the treatment of cryptosporidiosis are still not available and the biology and life cycle of C. parvum remain incompletely understood. The present study gives new insight into the parasite’s morphology, life cycle and host cell relationship.
This study utilised light microscopy, scanning electron microscopy, transmission electron microscopy and labeling of C. parvum surface receptors to examine infected cell cultures, cell-free cultures and oocyst stocks of C. parvum. Hence, this study compared different culture and different microscopic examination methods to determine the most suitable way to examine C. parvum’s morphology. Cell-free culture did not provide additional information to this study. However, it served as a valuable comparison for life cycle stages detected in the supernatant above cells which are expected to occur in the intestinal lumen of infected hosts. Scanning electron microscopy was the most suitable tool for obtaining information on the parasite’s morphology, whereas transmission electron microscopy enabled a view into the interior of stages. Employing light microscopy in this study was essential to progressively monitor live samples and visualise stages in the supernatant above cells, which were not attached to host tissue. In the course of this study a protocol was developed, which enabled the visualisation of Cryptosporidium receptors on the surface of parasites and/or host cell material via immunogold labeling with scanning electron microscopy.
For the first time, the entire range of C. parvum’s life cycle stages has been morphologically characterised (including their interactions with host cells) and presented in one study. A better understanding of the parasite’s biology, proliferation in host tissue and interactions with host cells will aid the drug development process.
Recent electron micrographs acquired in the course of this study revealed new life cycle stages, provided new information about the parasite’s morphology and its relationship with host cells. New insight into the host cell invasion process of C. parvum sporozoites as well as merozoites I and II was obtained. Features of gliding motility of the invasive stages were visualised and explained. Phenomena including binary fission - commonly employed by bacteria for the production of two identical daughter stages from one parent stage - and syzygy - the pairing of gamonts to exchange genetic material, described in gregarines - , was observed and described. Extracellular gamonts and gamont-like stages were also characterised; developing from intracellular trophozoites to finally break host cell contact and take their place in the life cycle of C. parvum, travelling free in the intestinal lumen. The morphology of the two different types of oocysts has been described and findings on receptor expression in their outer membranes are presented. Furthermore, C. parvum receptors were identified in the apical membranes surrounding parasite stages. C. parvum surface receptors were also found on host cell microvilli in proximity to invading and/or gliding parasites.
Additionally, the present study observed the effect that a C. parvum infection exerts on host tissue with respect to necrosis and apoptosis. This study also poses new ideas regarding the parasite’s host-dependent feeding behaviour.
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Silva, Sheila Oliveira de Souza. "Padronização de uma reação em cadeia pela polimerase em nested (nested-PCR) para detecção e diferenciação das espécies de Cryptosporidium spp e caracterização molecular de Cryptosporidium isolados de roedores sinantrópicos". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-24042012-151514/.
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Cryptosporidium spp são protozoários cosmopolita que acometem peixes, répteis, anfíbios, aves e mamíferos. Mais de 20 espécies são reconhecidas dentro deste gênero. Os roedores, grupos de organismos abundantes e ubíquos, têm sido considerados reservatórios de Cryptosporidium para humanos e animais de produção. As seqüências codificadoras da menor unidade ribossômica (18S rRNA) de Cryptosporidium spp caracterizam-se por intercalações entre regiões conservadas e polimórficas ao longo dos seus 1700 pares de bases. O objetivo deste estudo foi desenhar primers específicos para o gene 18S rRNA, potencialmente capazes de amplificar qualquer espécie ou genótipo de Cryptosporidium spp. e avaliar os atributos diagnósticos da nested-PCR baseadas em tais sondas. O desenho dos primers foi realizado de forma a amplificar um segmento de menor dimensão possível para se maximizar a sensibilidade do ensaio molecular e preservando o potencial discriminatório das seqüências amplificadas. A nestedPCR padronizada neste estudo (nPCR-SH) foi comparada com outro ensaio similar que vem sendo largamente utilizado para detecção e identificação de Cryptosporidium spp. no mundo todo (nPCR-XIAO). Também se objetivou caracterizar molecularmente amostras de Cryptosporidum spp. isoladas de roedores sinantrópicos, empregando-se estas sondas e sondas moleculares direcionadas. Foram capturados 45 roedores em áreas públicas da região urbana da cidade de Umuarama, Paraná. As amostras foram submetidas a três provas moleculares, sendo duas direcionadas ao gene18S rRNA (nPCR-SH e nPCR-XIAO) e outra, ao gene codificador da actina. A nPCR-SH foi testada com as amostras de Cryptosporidum parvum, Cryptosporidum andersoni, Cryptosporidum meleagridis, Cryptosporidum hominis, Cryptosporidum canis, Cryptosporidum serpentis e todas foram positivas. Dezesseis amostras de roedores foram positivas para a nPCR-SH, seis pela nPCR-XIAO e cinco pela nPCR dirigida ao gene codificador da actina. O sequenciamento dos fragmentos amplificados possibilitou a identificação de Cryptosporidum muris em três amostras de Rattus rattus, e dois novos genótipos de Cryptosporidium, os genótipos rato II e III. Genótipo rato II foi encontrado em uma amostra de Mus musculus e o genótipo III em doze amostras, sendo cinco Rattus rattus e sete Mus musculus. Os resultados deste estudo demonstraram que os primers desenhados para detecção do Cryptosporidium spp em amostras de fezes foram mais eficientes em amplificar regiões que permitem a distinção entre as espécies do parasito do que aqueles usados na PCR-XIAO. Nas amostras estudadas não foram encontrados genótipos ou espécies de Cryptosporidium que podem ser transmitidos a outras espécies como os zoonóticos, o que sugere que a importância destes animais na transmissão zoonótica de criptosporidiose é pouco relevante.Cryptosporidium spp are cosmopolitan protozoan that infect fish, reptiles, amphibians, birds and mammals. More than 20 species are recognized within this genus. Rodents are groups of abundant and ubiquitous organisms that have been considered reservoirs of Cryptosporidium for infection of humans and livestock. The coding sequences of the smallest unit ribosomal (18S rRNA) of Cryptosporidium spp are characterized by intercalations amongst polymorphic and conserved regions along its 1700 base pairs. The aim of this study was to design primers specific for the 18S rRNA gene, potentially capable of amplifying any species or genotype of Cryptosporidium spp., and evaluate the attributes of the nested-PCR diagnosis based on such probes. The design of primers was performed to amplify a smaller segment as possible to maximize the sensitivity of molecular testing and preserving the discriminatory potential of the sequences amplified. The nested-PCR standardized in this study (nPCR-SH) was compared with another similar assay that has been widely used for detection and identification of Cryptosporidium spp. worldwide (nPCR-XIAO). It also aimed to characterize molecularly Cryptosporidum spp. isolated from synanthropic rodents, using these probes and targeted molecular probes. Forty five rodents were captured in public areas of the urban area of Umuarama, Paraná. The samples were subjected to three molecular tests, two targeted to gene18S rRNA (nPCR-SH and nPCR-XIAO) and another targeted to the gene encoding actin. The nPCR-SH was tested with strains of Cryptosporidum parvum, Cryptosporidum andersoni, Cryptosporidum meleagridis, Cryptosporidum hominis Cryptosporidum canis, Cryptosporidum serpentis and all were positive. Sixteen samples of rodents were positive by nPCR-SH, six by nPCR-XIAO and five by nPCR targeted to the gene encoding actin. The sequencing of the amplified fragments allowed the identification of Cryptosporidum Muris in three samples of Rattus rattus, and two new genotypes of Cryptosporidium rat genotype II and III. It was found rat genotype II in a sample of Mus musculus and genotype III in twelve samples, five from Rattus rattus and seven from Mus Musculus.The results showed that the primers designed for detection of Cryptosporidium spp in fecal samples were more efficient in amplifying regions that allow the distinction amongst the parasite species than those used in the PCR-XIAO. Cryptosporidium species or genotypes transmitted to other species such as zoonotic were not found in the studied samples, which suggest that the importance of these animals in the zoonotic transmission of cryptosporidiosis is very limited.
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Drozd, Céline. "Comportement de Cryptosporidium spp. Dans l'eau : conséquences au niveau de la microfiltration tangentielle". Nancy 1, 1996. http://docnum.univ-lorraine.fr/public/SCD_T_1996_0386_DROZD.pdf.
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Cryptosporidium est un protozoaire intestinal responsable de diarrhées profuses provoquant une mortalité importante chez les personnes immunodéprimées. Son mode principal de transmission est l'eau contaminée. Ainsi en avril 1993 à Milwaukee (USA) une épidémie de cryptosporidiose d'origine hydrique a provoqué la contamination de 400 000 personnes. La fréquence et surtout l'amplitude de telles épidémies montrent bien que les systèmes de traitement classiques ne garantissent pas une sécurité totale en approvisionnement d'eau potable. Dans ce contexte l'adéquation de nouveaux systèmes de traitement d'eaux potables, comme les procédés de micro et d'ultrafiltration, pour l'élimination de Cryptosporidium. Doit être évaluée. L'objectif de cette étude a donc été d'évaluer l'efficacité des systèmes de potabilisation employant les procédés de microfiltration tangentielle pour l'élimination de Cryptosporidium à partir d'eaux de surface.
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Celis, Samanez Noemit Norma. "Criptosporidiasis en caninos críados en comunidades campesinas de tres distritos del departamento de Puno". Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2010. https://hdl.handle.net/20.500.12672/696.
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El objetivo del estudio fue estimar la prevalencia de Cryptosporidium sp. en caninos de comunidades campesinas, ubicadas en los distritos de Ajoyani; provincia de Carabaya; Palca y Santa Lucía; provincia de Lampa–Puno. Se recolectaron 123 muestras fecales de perros aparentemente sanos, de ambos sexos y diferentes edades, las que estuvieron comprendidas entre 1 mes y 16 años durante los meses de febrero y marzo del 2009. Las heces, fueron transportadas inmediatamente al Laboratorio del INIA-Quimsachata (Puno) donde se realizaron los frotices fecales, siendo fijados en metanol. Posteriormente se transportaron al Laboratorio de Parasitología de la FMV-UNMSM en Lima, para su diagnóstico; el cual se realizó usando la técnica de Ziehl-Neelsen modificada. La prevalencia general de Cryptosporidium sp. fue de 26.8±7.8%, se hallaron prevalencias de 19.0, 28.6 y 28.4% en los distritos de Ajoyani, Palca y Santa Lucía, respectivamente; los machos y hembras presentaron prevalencias de 28.3 y 17.6%, respectivamente y según los grupos etarios de 0-6, >6-12, >12-72 y >72 meses fueron de 46.2, 31.3, 19.7, 29.4%, respectivamente. Se aplicó la prueba de Chi cuadrado, con un nivel de significancia de 0.05. El análisis estadístico no mostró asociación significativa (p>0.05) entre este protozoo de caninos domésticos con el distrito, sexo y edad.
Palabras clave: Cryptosporidium sp, protozoo, zoonosis, prevalencia, perros.-- The objective of this study was to estimate the prevalence of Cryptosporidium sp. in dogs of rural communities, located in the districts of Ajoyani; province Carabaya; Palca and Santa Lucia; province Lampa, Puno. Were collected 123 fecal samples from dogs apparently healthy, of both sexes and different ages, which were between 1 month and 16 during the months of February and March 2009. Feces were transported to the Laboratory of INIA Quimsachata (Puno) where are the faecal frotices being fixed in methanol. Subsequently were transported to the Parasitology Laboratory of the FMV-Lima, for diagnosis; which was performed using the Ziehl-Neelsen modified. The overall prevalence of Cryptosporidium sp. was 26.8±7.8%, were found prevalences of 19.0, 28.6 and 28.4% in the districts of Ajoyani, Palca, and St. Lucia, respectively, males and females, showed prevalences of 28.3 and 17.6% respectively and according to age groups 0 -6,> 6-12,> 12-72 and > 72 months were 46.2, 31.3, 19.7, 29.4%, respectively. Was applied Chi-square test with a significance level of 0.05. Statistical analysis showed no significant association (p> 0.05) between this protozoan of domestic dogs with the district, sex and age. Keywords: Cryptosporidium sp, protozoa, zoonoses, prevalence, dogs.
Tesis
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Li, Hanbin. "Chemical inactivation of Cryptosporidium parvum in water". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60318.pdf.
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Bouzid, Maha. "Postgenomics analyses of species-specific Cryptosporidium genes". Thesis, University of East Anglia, 2010. https://ueaeprints.uea.ac.uk/19907/.
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Barakat, Farah Mukhlis. "Protective innate immune responses against Cryptosporidium parvum". Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8733.
Texto completoResumen
Cryptosporidiosis is a common infectious diarrhoeal disease of mammalian livestock and humans worldwide. The etiological organisms responsible are intestinal apicomplexans of the genus Cryptosporidium, including C. parvum, that infect intestinal epithelial cells. Immunocompromised or malnourished hosts develop severe life-threatening disease. Immunological elimination of Cryptosporidium requires CD4+ T cells and IFN-γ. Nevertheless, studies have shown innate immune responses have a significant protective role. Importantly, in T cell-deficient mice, IFN-γ is important for control of C. parvum infection. In innate immunity natural killer (NK) cells are major producers of IFN-γ and are activated by cytokines including type I IFNs but the roles of these components in immunity to Cryptosporidium infection have not been investigated. Therefore, the purpose of this project was to study the involvement of type I IFNs and NK cells in immunity to C. parvum employing in vitro and in vivo (murine) infection models. Enterocytes were shown capable of the production of type I IFNs in response to C. parvum infection. These cytokines directly inhibited parasite development in epithelial cells. Also, in neonatal SCID mice the level of infection increased after treatment with anti-type I IFN neutralising serum. A higher level of infection was observed in Rag2-/-γc-/- mice deficient in T, B and NK cells in comparison to Rag2-/- mice with a normal NK cell population and early mortality during chronic infection of adult animals was associated with the absence of NK cells. Using cultures of SCID mouse splenocytes, NK cells were the main source of IFN-γ in response to C. parvum antigen stimulation. However, IFN-γ was also found to have a protective role in Rag2-/-γc-/- mice, implying cells other than lymphocytes produce this cytokine. In conclusion, this is the first study to indicate important protective roles for type I IFNs and NK cells in innate immunity against C. parvum.
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Miller, Christopher. "Establishing Cryptosporidium parvum as a model organism". Thesis, University of Kent, 2017. https://kar.kent.ac.uk/66710/.
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Cryptosporidium parvum is among the most common parasites in the known world and represents one of the leading causes of death among the immunocompromised. As an apicomplexan, C. parvum has many similarities to other globally important parasites such as Plasmodium falciparum and Toxoplasma gondii. Among these similarities are a complex life cycle and the ability to invade host cells. However, unlike most other apicomplexans, the cryptosporidia appear to have lost their namesake organelle, the apicoplast, and drastically reduced the size of their genome. For decades this caused issues in classifying the cryptosporidia. This has been potentially resolved, however, by recent phylogenetic studies that revealed a strong relationship between the cryptosporidia and the gregarines. The gregarines were parasites exclusively of invertebrates, until the reclassification to include the cryptosporidia. Though research into apicomplexan evolution and biology is still a nascent field, even less is known about the invertebrate portion. This is largely due to the lack of molecular tools and culturing techniques that are required to explore any organism beyond basic phylogenetics, in addition to their medical irrelevance prior to the inclusion of Cryptosporidium. Therefore, C. parvum represents a potential model organism for the gregarines and the evolutionary adaptations of apicomplexans from invertebrate to vertebrate hosts. It was the purpose of this thesis, therefore, to establish the tools and methodologies that would be required to begin developing C. parvum as such. To achieve this, first I successfully developed the world's first long-term culturing system of C. parvum, capable of maintain a live parasite culture for 60 days. Additionally, I developed novel methods of detecting and characterising the infection, including NMR based characterisation of infection metabolomes which also revealed a potentially more involved role for Taurine in the pathology of the infection. Furthermore, to demonstrate the power and applicability of this new system I produced the first experimental evidence for a functional ISC system within C. parvum. This also adds to a now growing list of non-canonical mitochondria containing organisms that still maintain an active mitochondrial Fe/S cluster biosynthetic pathway. In conclusion, this thesis represents a large step forward for both the C. parvum and gregarine fields and establishes many of the necessary techniques required for a new push in understanding these apicomplexans and their organelles.
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Lally, Nicola C. "Antigen encoding gene fragments of Cryptosporidium parvum". Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/11026.
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Cryptosporidium parvum is an obligate intracellular protozoan which infects the gastrointestinal tract of a wide range of mammalian species. It is a common cause of diarrhoeal illness in humans and neonatal ruminants. Despite the medical and veterinary importance of C. parvum studies of this organism at the genetic level have begun only recently. This is due to the lack of interest shown in the parasite until it was recognised as a cause of human and animal disease, and also to the difficulty in producing sufficient parasite material in order to carry out such studies. The aim of this study was to identify, by screening a DNA library with anti-C. parvum antisera, genes or gene fragments encoding antigens of C.parvum. A C. parvum λgt 11 expression library was constructed using EcoRI-digested genomic DNA prepared from in vitro-excysted oocysts. Screening the library resulted in the isolation of two immunopositive clones, λCPR1, recognised by rat serum raised against excysted C. parvum oocysts, and λCPS10 recognised by serum from a gnotobiotic lamb experimentally infected with C. parvum. The DNA inserts from these clones (CPR1 and CPS10 respectively) were subcloned into the pMS plasmid expression vectors, and the recombinant peptides expressed by the resulting subclones analysed by Western blotting. Subclones containing CPS10 expressed a peptide which was recognised by some, but not all, lambs infected with C. parvum. When CPR1 was subcloned into pMS1S the resulting subclone expressed a 200kDa β-galactosidase fusion protein. This fusion protein was partially purified and used to raise polyclonal antiserum in a rabbit. Western blotting indicated that this serum recognised a 190kDa peptide constituent of the C. parvum oocyst wall. The CPR1 DNA fragment was sequenced in both directions and found to consist of 2359 nucleotides, 2358 of which form a continuous open reading frame. The DNA sequence has a realtively low G+ C content (39.1%) and there is a corresponding bias towards the use of codons ending in A or T (82.1%) within this open reading frame.
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Palermo, Cindy. "Cryptosporidium in fish: Morphological and molecular characterisation". Thesis, Palermo, Cindy (2016) Cryptosporidium in fish: Morphological and molecular characterisation. Honours thesis, Murdoch University, 2016. https://researchrepository.murdoch.edu.au/id/eprint/35248/.
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Cryptosporidium is an Apicomplexa protozoan parasite that causes gastrointestinal illness in a wide range of vertebrate hosts, including humans. Little is known of the epidemiology of Cryptosporidium in fish. This study investigated the prevalence of Cryptosporidium in goldfish (Carassius auratus) (n=216) and mullet (Mugil cephalus) (n=13). Goldfish can be host to a range of Cryptosporidium sp. and research has shown that mullet has been host to genotype 3, therefore sampling from these breeds of fish could provide further characterisation. The fish were acquired from three sources in Metropolitan Perth, Western Australia; Vebas Aquarium (n=16), Water Garden Life fish farm (n=200) and a local bait shop in Fremantle (n=13). Intestines and stomachs were dissected and half kept for histology and the remaining half used for DNA extraction. All samples were initially screened at the 18S locus by quantitative PCR (qPCR) and positives further analysed by nested PCR and sequencing at the 18S and actin loci. Further subtyping was conducted on human-infectious species at the glycoprotein 60 (gp60) locus. The overall prevalence by qPCR was 30.1% (69/229) (CI 24.2-36.1). Of these only 34 samples amplified at the 18S locus and 23 clean sequences were obtained, with the remaining 11 sequences exhibiting mixed chromatograms. At the actin locus, 6 samples were successfully amplified and 3 clean chromatograms were obtained. Sequencing and phylogenetic analysis at the 18S locus identified C. parvum (n=2), C. hominis (n=10) and a novel species (n=11), which was identical to a novel genotype identified in a single isolate from a goldfish from a previous Honours project. Phylogenetic analysis confirmed that this novel genotype was genetically distinct and most closely related to C. scopthalmi (10.4% genetic distance). At the actin locus, all three isolates sequenced belonged to the novel genotype, which again grouped with C. scopthalmi and exhibited 14.1% genetic distance at this locus. Subtyping of C. hominis and C. parvum isolates at the gp60 locus was successful for 3 C. hominis isolates and all were typed as 1bA10G2, which is the main subtype involved in human outbreaks of cryptosporidiosis. Unfortunately, the parasite could not be identified in histological sections, which may be due to the patchy distribution of Cryptosporidium infections and rapid tissue autolysis. This is the first characterisation of the novel genotype at the actin locus and provides further support for its species status. The identification of human-infectious species in these fish is of public health concern as it may enable control of cryptosporidiosis outbreaks. Future research should focus on analysis of a wider range of fish species as well as clinical signs and histology to better understand the host range and pathogenicity of the novel genotype and the prevalence of human-infectious species in fish.
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Ng, Josephine Su Yin. "Molecular epidemiology and metabolomic characterisation of Cryptosporidium". Thesis, Ng, Josephine Su Yin (2017) Molecular epidemiology and metabolomic characterisation of Cryptosporidium. PhD thesis, Murdoch University, 2017. https://researchrepository.murdoch.edu.au/id/eprint/38641/.
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This thesis examined the molecular epidemiology of the important enteric parasite, Cryptosporidium in Australia with particular reference to cryptosporidiosis in Aboriginal communities, outbreaks, zoonotic transmission and also conducted the first metabolomics analysis of Cryptosporidium.
Chapter 3 revealed striking differences in the epidemiology of Cryptosporidium between Aboriginal and non-Aboriginal people, with notification rates among Aboriginal people up to 50 times higher. Aboriginal people were predominantly infected with C. hominis subtype IdA15G1 and non-Aboriginal people were predominantly infected with C. hominis subtype IbA10G2. Chapters 4 and 5 explored the epidemiology of outbreaks with the C. hominis IbA10G2 subtype, the major subtype identified in all outbreaks.
Chapter 6 examined zoonotic transmission of Cryptosporidium species in rural NSW. Three species of Cryptosporidium were detected in calves; C. parvum, C. bovis and C. ryanae and two in humans; C. parvum and C. bovis. Subtyping identified the concurrence of C. parvum subtypes between calves and humans and this coupled with the identification of the cattle-specific C. bovis in humans and calves provides supportive evidence of zoonotic transmission.
Chapter 7 developed a reproducible faecal extraction method for untargeted gas chromatography-mass spectrometry (GC-MS) analysis and identified distinct differences in faecal metabolite profiles between infected and un-infected individuals. However, as the metabolome is sensitive to external perturbations, a more controlled metabolomics analysis of faecal metabolite profiles was conducted in Chapter 8 using experimentally infected mice. Despite the differences in faecal metabolite profiles between Cryptosporidium infected humans and mice, metabolomic analysis in both studies was still able to clearly differentiate between infected and uninfected hosts, as well as provide information on the metabolic activity of the parasite during the infection based on faecal metabolite profiles.
The finding of this thesis will greatly assist in our understanding of molecular epidemiology of Cryptosporidium in Australia and the biochemistry of this important parasite.
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Bolland, Samuel John. "Describing new species of Cryptosporidium in fish". Thesis, Bolland, Samuel John (2019) Describing new species of Cryptosporidium in fish. Honours thesis, Murdoch University, 2019. https://researchrepository.murdoch.edu.au/id/eprint/54961/.
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The protozoan parasite Cryptosporidium (class Gregarinomorphea, subclass Cryptogregaria) causes a range of symptoms in humans and clinical signs in animals from asymptomatic to severe diarrhoea and death. However, relatively little information is available regarding the taxonomy, zoonotic potential and host relationships of Cryptosporidium in fish. Previous studies have indicated that extensive genetic diversity exists with piscine Cryptosporidium species and genotypes. The present study screened fish from two sources in Perth, Western Australia; Water Garden Life Fish Farm (n=233) and Vebas Aquarium (n=234) for Cryptosporidium. Intestinal and gastric tissue was dissected out and screened by PCR and Sanger sequencing using Cryptosporidium specific primers that amplify DNA at the 18S and actin loci. Samples that were positive by PCR were also screened by histology. The overall prevalence of Cryptosporidium was 4.3% (20/467, 95% CI: 2.6-6.5). Phylogenetic analyses of 18S sequences identified C. huwi (n=11), piscine genotype 2 (n=3), piscine genotype 4 (n=1) and piscine genotype 7 (n=5). In addition, ten novel sequences most genetically similar to species from the genus Goussia and a sequence from the non-parasitic alveolate Colpodella were identified. Sequences amplified at the actin locus were C. huwi (n=7), piscine genotype 2 (n=1), piscine genotype 7 (n=1) and one novel Cryptosporidium sequence. Piscine genotype 2 was most closely related to piscine genotype 4 (4.1% genetic distance) and exhibited 11.1-11.9%, 15.3% and 22.3% genetic distances from C. molnari, C. huwi and C. scophthtalmi, respectively. At the actin locus, piscine genotype 2 was again most closely related to piscine genotype 4 (7.2% genetic distance) and exhibited genetic distances ranging from 18.1% (C. molnari) to 20% (C. huwi) and 26.1% for C. scophthalmi, respectively, and 20.7%- 32% genetic distance from all other species. Phylogenetic analysis of concatenated 18S and actin sequences showed that piscine genotype 2 exhibited 14% (C. molnari) to 24.6% (C. canis) genetic distance from all other Cryptosporidium spp. Using concatenated sequences, piscine genotype 7 was most closely related to C. huwi at a genetic distance of 7.5% and exhibited 13.4% (C. molnari) to 23.1% (C. scophthalmi) genetic distances from other piscine Cryptosporidium species, with 17.9% (C. testudinis) to 22.6% (C. canis) genetic distance from all non-piscine Cryptosporidium species. Piscine genotype 2 exhibited 14.6% genetic distance from piscine genotype 7. These genetic distances at two separate loci confirm the genetic distinctness of piscine genotype 2 and piscine genotype 7 and indicate that they are likely novel species. Additionally, 10/467 (2.1%, 95% CI; 1.0-3.9) samples that were positive at the 18S locus, produced sequences most genetically similar to species from the genus Goussia, subclass Conoidasida, nine were novel sequences and were compared at the 18S locus to established species of Goussia and genetic distances between 1.9% and 14.8% were identified, adding to the diversity of this genus. Furthermore, Schyzocotyle acheilognathi, the invasive Asian fish tapeworm, was identified (n=2) by morphology infecting goldfish from a local fish farm. This is only the second report of S. acheilognathi in Western Australia as it was first discovered in 2018 by a Murdoch researcher in feral goldfish from a Lake in Joondalup. Analysis at additional loci or whole genome sequencing will shed more light on the evolutionary relationships between Cryptosporidium species, while next generation sequencing would elucidate the prevalence of mixed infections of Cryptosporidium in fish. The genetic data produced by the present study describes two piscine genotypes of Cryptosporidium (that are likely valid species) in detail and provides new genetic data on the diversity of Goussia spp.
Keywords: Cryptosporidium, 18S, actin, Schyzocotyle acheilognathi, Goussia
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Sargent, Keith. "Molecular characterization of Cryptosporidium from selected hosts". Thesis, Sargent, Keith (1997) Molecular characterization of Cryptosporidium from selected hosts. Honours thesis, Murdoch University, 1997. https://researchrepository.murdoch.edu.au/id/eprint/58326/.
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In this study, domestic dogs and cats in the metropolitan area of the city of Perth, Western Australia, and wild mice caught at various agricultural sites in rural Victoria, were screened for the presence of the coccidian protozoan parasite Cryptosporidium.
This study was undertaken to determine the prevalence of Cryptosporidium in these three groups of animals, and to genetically characterize isolates from positive hosts in order to examine the extent of genetic variation between isolates of Cryptosporidium, and to asses their potential for zoonotic transmission. It was hypothesized that Cryptosporidium is common in domestic and wild animals and differs genetically to isolates of Cryptosporidium from humans.
Of 116 faecal samples collected from domestic dogs, none were found to be positive for Cryptosporidium. Of 162 faecal samples collected from domestic cats, two were positive for Cryptosporidium (a prevalence of 1.2%). Morphological characterization of oocysts of these isolates showed them to have an average size of 4.6 x 4.0 µm, smaller in size than C. parvum isolates typically seen in humans (5.0 x 4.5 µm). Sequence analysis of 18S rDNA sequences showed cat isolates of Cryptosporidium to have a distinct genotype from those previously reported to occur in humans and cattle. In addition, phylogenetic analysis with other C. parvum isolates and Cryptosporidium species, grouped the cat isolates as a distinctly separate group. These results suggest that cats may harbour a distinct "cat adapted" strain or species of Cryptosporidium.
Of 182 mouse faecal samples screened, 11 were found to be positive for Cryptosporidium (a prevalence of 6.0%). Analysis of 18S rDNA sequences showed these isolates to have a distinct genotype from those reported in humans and cattle. The finding that mouse isolates of Cryptosporidium harbour a unique genotype to that seen in isolates recovered from humans, suggests that mice are unlikely to be an important zoonotic reservoir of infection for humans.
In addition, a rDNA PCR-RFLP approach, designed for the purpose of characterizing C. parvum isolates, differentiated human and calf genotypes previously identified by rDNA sequencing. Furthermore this technique detected intergroup genetic variation within isolates recovered from humans and animals.
The results of this study supported the general hypothesis under investigation. Results suggest that C. parvum is not a uniform species, that there are distinct genotypes of C. parvum present in isolates from animal and human hosts, and as such it would appear that there is a need for a reappraisal of the current taxonomy of the genus Cryptosporidium
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Mychajlonka, Meisha Natasha. "Worldwide Distribution of Cryptosporidium Species in Bovines". Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/579293.
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The following research-based paper will provide a detailed list of all Cryptosporidium species known, to date, to infect bovine populations worldwide. Prevalence data from around the world, including Australia, Brazil, Canada, China, England, Egypt, India, Italy, Japan, Spain, Sweden, the United States of America and others, are detailed and tabularly presented. Cryptosporidium parvum, C. andersoni, C. bovis and C. ryanae are the major relevant species of Cryptosporidium that readily infect bovines. Information on infection duration, oocyst shedding volumes and symptomology on each major species is encompassed. The current genomics and subtypes of this organism are detailed and discussed. Treatment including vaccination, chemotherapy and immunotherapy are reviewed. Lastly, the future developments in the bovine Cryptosporidium field are touched upon.
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Cifrino, Andrew Charles 1955. "Isolation and concentration of Cryptosporidium from water". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191904.
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A method was developed for the concentration and detection of Cryotosooridium oocysts in water. Oocysts were concentrated from 100 gallon volumes of tapwater using spun polypropylene cartridge filters. The filter was backflushed and washed with 0.1% Tween 80 in deionized water. Centrifugation of the eluate resulted in a suspension containing both oocysts and sediment. Density gradient centrifugation was used to remove the sediment. Membrane filtration of the final suspension was followed by labelling the oocysts with a fluorescein linked monoclonal antibody. Enumeration of the oocysts was accomplished by fluorescence microscopic observation of the membrane filter. The recovery efficiency using this technique averaged 51%. Furthermore, the detection of as few as one oocyst per gallon of water was possible. This method can now be used for the investigation of waterborne outbreaks and to study the occurrence of Cryotosooridium in water.
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Sturbaum, Gregory Dean. "Cryptosporidium parvum, molecular environmental detection and implications". Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/280454.
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Cryptosporidiosis is a major cause of diarrheal illness worldwide and characterized by several daily bowel movements, resulting in fluid loss and dehydration. Two species, Cryptosporidium hominis and C. parvum are the main causative agents in human infection. Complicating matters for disinfection, epidemiology, and treatment studies, C. parvum isolates infect multiple mammalian species while C. hominis solely infects humans. The purpose of this dissertation was to: (1) develop a C. parvum PCR based detection method and discuss its limitations; and (2) to extend current epidemiological and molecular data rationalizing the multiple C. parvum host specific infectivity patterns. To fulfill these two objectives, three separate experiments were designed and executed. The results from which are included in the appendix as peer reviewed published manuscripts and are the basis of this dissertation. The first manuscript outlines the use and validation of microscopic micromanipulation to isolate and deliver low numbers of C. parvum oocysts to a test vial of interest. In addition, a nested PCR primer set was developed targeting the 18S rRNA and tested for sensitivity using micromanipulation and specificity using isolated DNA from multiple different species. It was determined that micromanipulation is an accurate technique able to deliver low numbers of oocysts to a test vial of interest. The nested PCR protocol had LLOD, in replicates of 50 and laboratory grade water, of 100% with ten oocysts and 38% with a single oocyst. The second manuscript compared detection efficiencies of the EPA Method 1623 with the nested PCR protocol outlined in the first manuscript. Both methods had equal detection efficiencies giving positive detection at the five-oocyst level. In addition, non-specific PCR amplification results generated during the study revealed specificity issues that have implications effecting past, current and future molecular detection validation processes. The final manuscript describes nucleotide and deduced amino acid differences between the C. parvum and C. hominis attachment/invasion surface proteins Cpgp 40/15, p23, and GP900. This information has implications explaining host-specificity differences observed among Cryptosporidium spp.
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Baishanbo, Asiya. "La cryptosporidiose : modèles expérimentaux d'infection par Cryptosporidium hominis et Cryptosporidium parvum génotypes 2 et d'hypersensibilité viscérale post-infectieuse. Applications pharmacologiques". Rouen, 2005. http://www.theses.fr/2005ROUE01NR.
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Chez l'homme, les génotypes de Cryptosporidium les plus fréquemment rencontrés sont C. Hominis et C. Parvum. Malgré des travaux récents, la physiopathologie de la cryptosporidiose reste mal comprise et l'arsenal thérapeutique contre cette parasitose est pauvre. Dans ce contexte, notre objectif a été de mettre au point des modèles animaux d'infection par C. Hominis et C. Parvum. L'utilisation de la gerbille (Meriones unguiculatus) immunodéprimée permet d'obtenir une infection stable avec les 2 espèces étudiées après inoculation de 100 à 200 000 oocytes de parasites. En outre dans ce modèle, l'infection non seulement de l'intestin mais également des voies biliaires par Cryptospordium autorise la réalisation d'études pharmacologiques. C'est ainsi qu'en utilisant ce modèle, il a pu être démontré l'activité de la paromomycine et du nitazoxanide sur l'infection intestinale et du nitazoxanide sur la cryptosporidiose biliaire. Toutefois, l'infection n'est pas troujours complètement éradiquée. Aussi dans l'optique de la recherche d'un nouvel agent antiprotozoaire, 52 isoflavones ont été criblées pour leur activité contre Cryptosporidium parvum, Neospora caninum et Sarcocytis neurona in vitro. Les 2 molécules les plus actives in vitro ont été étudiées in vivo dans le modèle gerbille et elles apparaissent plus actives que le nitazoxanide à la fois sur l'infection intestinale et biliaire. Par ailleurs, chez l'homme immunocompétent, de nombreux arguments apparaissent pour impliquer la cryptosporidiose dans la survenue à long terme d'un syndrome de l'intestin irritable post infectieux. Afin de confirmer cette hypothèse, l'hypersensibilité viscérale intestinale a été étudiée dans un modèle de raton immunocompétent. Cent vingt jours après une infection spontanément résolutive par C. Parvum, une hypersensibilité viscérale associée à une augmentation tissulaire de l'activité myeloperoxydase apparaît chez les rats préalablement infectés par comparaison avec des rats sains. Cette hypersensibilité n'apparaît pas lorsque l'infection parasitaire a été traitée préventivement par le nitazoxanideCryptosporidium sp. Are emergent pathogenic protozoan parasites now recognised as one of the most common causes of human enteric infections. In man, the most prevalent genotypes are Cryptosporidium hominis (previously Cryptosporidium parvum type 1) and the bovine C. Parvum genotype 2. In spite of recent advances, the pathogenesis of cryptosporidiosis is presently poorly understood and a limited number of effective anticryptosporidial therapeutic agent are available. Our objective was to develop Cryptosporidium sp. Infection models in immunocompetent rats and immunosuppressed gerbil to assess infectivity and pathogenicity, and to screen anticryptosporidial agents. C. Hominis and C. Parvum genotype 2 oocyts were found sustainably infective for immunosuppressed Mongolian gerbils at doses ranging from 100 to 200 000 oocysts/ animal for both isolates. Moreover, this model was found suitable to study both ileal and biliary cryptosporodial agents. Although it did not achieve complete removal of Cryptosporidium sp. From the infected host, nitazoxanide was the only pharmacological agent effective againts gall bladder infection. The in vitro activity of 52 flavonoids was studied against the Apicomplexan pathogenic parasites Cryptosporidium parvum, Sarcocystis neurona and Neospora caninum. Twenty compounds were found able to significantlly and dose dependently inhibit in vitro parasite development and exhibited more than 95% inhibition against one or, for 8 agents, the three coccidian parasites. In the immunosuppressed gerbil model, 2 agents (RM 6427 and RM 6428) were found efficient not only in decreasing oocyst shedding but also in limiting C. Parvum intracellular developpment in the gut and in the biliary tract. These activities were significantly higher than those of nitazoxanide and paromomycin. In humans, another concern in the physiopathology of cryptosporidiosis is its possible role in the development of post infectious irritable bowel disease. In an immunocompetent suckling rat model, an increases sensitivity to jejunal distension at any distending volume compared to uninfected control rats was obserced 120 days after recovery of Cryptosporidium parvum infection. In accordance with clinicam studies in man, present results in rats prompt investigation of the long-term role of enteric Cryptospordium parvum infection in the pathogenesis of irritable bowel disease
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Oliveira, Paula Vilma de. "Ocorrencia de cistos de Giardia spp. e oocistos de Cryptosporidium spp. no rio Atibaia, bacia do rio Piracicaba, Campinas, São Paulo". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313872.
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Orientador: Regina Maura Bueno FrancoDissertação (mestrado) - Universidade Estadual de Campinas. Instituto de Biologia
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Resumo: Giardia spp. e Cryptosporidium spp. estão amplamente dispersos no ambiente aquático e foram responsáveis por diversos surtos de giardiose e criptosporidiose por veiculação hídrica em vários países. A presença destes patógenos em água utilizada para consumo humano é um fator de risco para aquisição destas parasitoses porque cistos e oocistos são resistentes aos processos de tratamento e às condições ambientais. Deste modo, a preocupação em relação à contaminação das fontes de água para uso humano por estes protozoários é crescente. No Brasil, há registros da ocorrência de ambos organismos em água superficial e subterrânea e em esgoto bruto e tratado. Atualmente, há uma recomendação oficial para a implantação da pesquisa de cistos e oocistos em água tratada. Assim, é necessário ter conhecimento sobre a freqüência e a distribuição destes parasitos nos mananciais. Os objetivos do presente estudo foram: i) verificar a ocorrência de cistos de Giardia e oocistos de Cryptosporidium em amostras de água bruta superficial do Rio Atibaia (Campinas, São Paulo) utilizando a técnica de filtração em membrana (47 mm diâmetro; 3 ?m de porosidade nominal); ii) avaliar a influência do desaguamento do Ribeirão Pinheiros na qualidade da água do Rio Atibaia mediante a comparação e a correlação entre parâmetros microbiológicos, físicos, pluviométricos e concentração de cistos e oocistos em dois pontos: à montante (A1) e à jusante (A2) do desaguamento do Ribeirão Pinheiros; e iii) verificar a ocorrência de variação sazonal destes protozoários na água superficial do Rio Atibaia. De março de 2002 a abril de 2003, 50 amostras de água foram analisadas. No ponto A1, cistos de Giardia foram detectados em 52,0% das amostras (concentração = 25,12 cistos/l), enquanto no ponto A2, a positividade foi de 76,0% (64,16 cistos/l). Oocistos de Cryptosporidium foram detectados somente no ponto A2, em 0,04% das amostras (0,8 oocistos/l). Houve diferença significativa na concentração de cistos entre os pontos A1 e A2 (p = 0,011) e correlação entre a pluviosidade e os parâmetros: concentração de cistos de Giardia (r = 0,611); coliformes totais (r = 0,467) e fecais (r = 0,467) no ponto A2. Em ambos os pontos, não foi encontrada correlação entre concentração de cistos de Giardia e as variáveis: coliformes totais (A1: r = -0,276; A2; r = -0,201), fecais (A1: r = -0,187; A2: r = -0,201) e turbidez (A1: r = -0,252; A2: r = -0,055). Dentre estes parâmetros, apenas a turbidez teve variação entre verão/inverno e verão/outono (p = 0,06). A técnica de filtração em membrana apresentou uma eficiência de recuperação de 72,2% para cistos de Giardia e de 65,1% para oocistos de Cryptosporidium. Os resultados obtidos neste estudo são relevantes porque o Rio Atibaia é o manancial que abastece a cidade de Campinas e outros municípios da região e o conhecimento da epidemiologia ambiental destes protozoários é importante do ponto de vista da Saúde Pública e também das companhias de tratamento de água
Abstract: Giardia spp. and Cryptosporidium spp. are widely dispersed in the aquatic environment and are responsible for several waterborne outbreaks of giardiosis and cryptosporidiosis in many countries. The occurrence of these pathogens in drinking water is a risk factor for human infection because of the resistance of cyst and oocyst to water treatment processes and to the environment. Nowadays, there is an increasing concern about drinking water contamination by these protozoans. In Brazil, the presence of both organisms was registered in groundwater and superficial water and in raw and treated sewage. Currently, there is an official recommendation for monitoring the presence of Giardia and Cryptosporidium in drinking water samples; thus a federal decree aims to establish researches for (oo)cysts detection in treated water. The knowledge about the frequency and distribution of these protozoan parasites in water sources is necessary to establish policies on public health. The aims of the present study are: i) to verify the occurrence of Giardia cysts and Cryptosporidium oocysts in Atibaia River¿s (Campinas City, São Paulo State) superficial raw water samples using a membrane filtration method (47 mm diameter; 3 ?m of nominal porosity; ii) to evaluate the influence of the discharge of Pinheiros Stream on the water quality of the Atibaia River by the correlationship among microbiological and physical parameters, rainfall and oocysts levels in two points: upstream (A1) and downstream (A2) of Pinheiros Stream; and iii) to verify the seasonal variation of these protozoa occurrence in the superficial water of Atibaia River. From March 2002 to April 2003, 50 water samples were collected. In point A1, Giardia cysts were detected in 52,0% of the samples (concentration = 25,12 cysts/l) while in point A2 the positivity for this parasite was 76,0% (concentration = 64,16 cysts/l). Cryptosporidium oocysts were detected only in A2 point, in 0,04% of the samples (concentration = 0,8 oocysts/l). There was a significant difference for cysts concentration between A1 and A2 points (p = 0,011) and among rainfall and the parameters: cyst concentration (r = 0,611); total (r = 0,467) and fecal coliforms (r = 0,467) in A2 point. In both points, it was not found a correlationship among cyst concentration and the following parameters: total coliforms (A1: r = -0,276; A2; r = -0,201), fecal coliforms (A1: r = -0,187; A2: r = -0,201) and turbidity (A1: r = -0,252; A2: r = -0,055). The turbidity showed a variation between summer and winter periods as well as summer and fall periods (p = 0,06). The membrane filtration technique attained recovery efficiency rates of 72,2% for Giardia cysts and 65,1% for Cryptosporidium oocysts. The data obtained in this study are relevant because the Atibaia River is the major water source found in Campinas and other cities in the region. Thus, the knowledge about the environmental epidemiology of these protozoa is of very important to policies on to the Public Health and to the drinking water industry
Mestrado
Parasitologia
Mestre em Parasitologia
29
França, Rita Borges. "Cryptosporidium spp., Giardia spp. e ovos de helmintos em esgoto hospitalar : destruição e analise de dano estrutural dos protozoarios apos o processo fotoeletroquimico". [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315635.
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Orientador: Regina Maura Bueno FrancoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: O efluente hospitalar apresenta, dentre seus componentes, organismos como vírus, bactérias, protozoários e helmintos, que ocasionam muitas doenças com implicações em saúde pública. Cryptosporidium spp. e Giardia spp. são protozoários parasitos com grande importância por sua veiculação hídrica e cujas formas infectantes são resistentes aos processos rotineiramente usados no tratamento de água e esgoto. A transmissão destes pode ocorrer com a ingestão dos oocistos e cistos eventualmente presentes na água e nos alimentos contaminados, por contato direto (pessoa a pessoa), por contato indireto (objetos contaminados), pelo contato sexual ou pode ser zoonótica. Os métodos mais utilizados para desinfecção em estações de tratamento são a aeração, cloração e irradiação por UV, mas a cloração, não é suficiente para eliminar oocistos de Cryptosporidium spp e cistos de Giardia spp. A tecnologia eletroquímica oferece um meio de tratamento eficiente para a oxidação. da carga orgânica e microbiológica degradando-as ou mineralizando-as. O presente trabalho teve por objetivos: (1) verificar a ocorrência natural de Cryptosporidium spp. e Giardia spp. em amostras de esgoto do Hospital de Clínicas de Campinas, utilizando o método, de centrífugo-concentração seguido de clarificação com éter e visualização por, imunofluorescência direta, durante o período de um ano; (2) verificar a presença de ovos e larvas de helmintos no esgoto hospitalar empregando a técnica da NOM (Norma Oficial Mexicana) e (3) avaliar a taxa de destruição e o dano estrutural causado em cistos e oocistos após o tratamento fotoeletroquímico. No esgoto hospitalar bruto 4,1 % e 58,3 % das amostras foram positivas para Cryptosporidium spp. e Giardia spp., respectivamente, sendo observada a concentração média de 2,7 x 103 oocistos/L e 3,8 x 105 cistos/L. Foi possível verificar a elevada presença de helmintos, com 90 % das amostras apresentando positividade e concentração de 5,8 x 104 ovos/L e 4,0 x 105 larvas/L. Os protozoários e helmintos presentes em altas concentrações no esgoto hospitalar representam uma séria ameaça à saúde humana. Para os ensaios com o tratamento fotoeletroquímico, amostras de 1 L de esgoto hospitalar foram artificialmente contaminadas com cistos e oocistos e, posteriormente, submetidas a esse tratamento em um reator de bancada, com tempos de exposição de 0,30, 60 e 90 minutos. Por meio das técnicas de imunofluorescência direta, microscopia de contraste de fase e microscopia eletrônica de varredura verificou-se o dano estrutural causado pela ação dos radicais hidroxila nesses protozoários patogênicos e a destruição dos mesmos. O tratamento fotoeletroquímico mostrou uma redução na concentração dos protozoários nos tempos de 30 e 60 minutos e após 90 minutos, nenhum cisto ou oocisto foi detectado. A presença do cloreto no efluente bruto (média de 45 mg/l) desencadeou uma potencializaçáo da ação de mecanismo do reator, gerando efeito associado com a eletrólise, dos radicais hidroxila com a formação de hipoclorito
Abstract: Hospital effluent presents organisms as virus, bacteria, protozoan and helminthes, that cause many iIInesses with implications in public health. Cryptosporidium spp. and Giardia spp. are parasites with waterborne importance and its cysts and oocysts are resistant to the routinely processes used in water treatment. Their transmission can occur by oocysts and cysts ingestion in the water and contaminated foods, by direct contact (person the person), by indirect contact (contaminated objects), by sexual contact or zoonotic. The methods used for disinfection and treatment of sewage are aeration, chlorination and irradiation of ultraviolet light, but the treatment by chlorination is not enough to inactivate Cryptosporidium spp. oocyst and Giardia spp. cysts. The electrochemical technology offers an efficient treatment for the oxidation of organic and microbiological load, degrading and mineralizing them. The present work had as objectives: (1) to verify the natural occurrence of Cryptosporidium spp. and Giardia spp. in samples of Clinical Hospital sewage from Unicamp using centrifugal concentration followed by clarification with ether method and visualization by immunoflourescence assay, during one year, (2) to verify the presence of eggs and larvae of helminthes in the hospital sewage by NOM (Mexican Official Norm) technique and (3) to evaluate the destruction rate and the structural damage caused in cysts and oocysts by photoelectrochemical treatment. In raw hospital sewage 4.1 % and 58.3% of the samples were positive for Cryptosporidium spp. and Giardia spp., respectively, with concentrations of 2.7 x 103 oocysts/L and 3.8 x 105 cysts/L. The high presence of helminthes, 90% positive, with 5.8 x 104 eggs/L and 4.0 x 105 larvae/L and protozoan in hospital sewage represent a serious threat to human being health. For the assays with the photoelectrochemical treatment, samples of 1 L of hospital sewage artificially contaminated with cysts and oocysts ! were submitted to this treatment in a bench reactor, with times of exposition of 0, 30, 60 and 90 minutes. By the techniques of immunofluorescence assays, microscopy of phase contrast and scanning electronic microscopy, the structural damage and destruction were observed, caused by hydroxyl radicals in these pathogenic protozoans. The photoelectrochemical treatment showed a concentration reduction of the protozoan in 30 and 60 minutes, and after 90 minutes no cyst or oocysts were detected. The chloride present in raw effluent (average of 45 rng/L) unchained a potential action of the reactor mechanism, generating an effect associated with electrolysis of the hydroxyl radicals with production of hypochlorite
Mestrado
Parasitologia
Mestre em Parasitologia
30
Coutinho, Tatiane Sueli. "Avaliação do efeito de microrganismos probióticos sobre Cryptosporidium parvum em camundongos C57BL/6 imunossuprimidos". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/97/97131/tde-20082013-164015/.
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Os probióticos são produtos ou preparações que contém microrganismos viáveis, com concentrações definidas, capazes de alterar a microbiota intestinal do hospedeiro, exercendo efeitos benéficos a sua saúde. Os microrganismos mais usados para esta finalidade são as bactérias lácticas, destacando-se espécies de Lactobacillus. Apesar do avanço científico nesta área, poucos estudos são encontrados a respeito da ação probiótica sobre protozoários, como Cryptosporidium parvum, um parasito intestinal importante por causar uma das principais infecções oportunistas em indivíduos imunodebilitados, como aidéticos e transplantados. Os produtos probióticos podem ser uma alternativa para o tratamento da criptosporidiose, uma vez que, ainda, não há um tratamento eficaz contra esta parasitose. Sendo assim, o presente estudo visou avaliar a ação de cepas de Lactobacillus plantarum, L. acidophillus e L. delbruekii, na forma de pool, sobre Cryptosporidium parvum em camundongos imunossuprimidos. Os experimentos foram desenvolvidos utilizando-se 42 animais divididos em seis grupos: Controle - não imunossuprimidos, não infectados e não tratados; Imuno - imunossuprimidos, não infectados e não tratados; Não tratado - imunossuprimidos, infectados e não tratado; NTZ - imunossuprimidos, infectados e tratados com o antiprozotoário nitazoxanida (150mg/kg); PRO - imunossuprimidos, infectados e tratados com a preparação probiótica (3x10¹²UFC/mL); e, Preventivo - imunossuprimidos, tratados com a preparação probiótica e posteriormente infectados. Após 12 dias de imunossupressão os animais foram infectados com 1,6x106 oocistos e, os respectivos tratamentos iniciados após cinco dias da inoculação dos oocistos. A infecção foi analisada pela contagem de oocistos nas fezes, purificados pela técnica de sedimentação de formol-éter. A colonização intestinal pelos lactobacilos foi analisada pela técnica de \"pour plate\" em ágar MRS com antibiótico Rifampcina. O desempenho nutricional dos camundongos foi analisado por meio da conversão alimentar, uma relação entre a quantidade de ração consumida e o ganho de peso dos animais. Os resultados demonstraram que os animais que receberam o tratamento preventivo com os probióticos apresentaram uma eliminação de oocistos significativamente menor (P<=0,05) que os demais grupos infectados. O tratamento com a preparação probiótica, pós-infecção, também se mostrou eficaz, pois todos os animais eliminaram a infecção. Estes resultados podem ser explicados por meio do mecanismo de ação conhecido como exclusão competitiva, devido a colonização do trato gastrointestinal ou, pela produção de substância antimicrobiana, produzida por Lactobacillus, que apresentou ação sobre os oocistos. Observou-se, também, que os animais tratados com probióticos tiveram um melhor desempenho nutricional. Estes resultados confirmam a hipótese que microrganismos com propriedades probióticas representam uma forma alternativa, e promissora, na prevenção e tratamento da criptosporidiose.The probiotics are products or preparation containing viable microorganisms, in defined concentrations, capable of change the host\'s microbiota, exerting beneficial effects on the host\'s health. The most important microorganisms which present these properties belong to the group of lactic acid bacterium, mainly species of Lactobacillus. Even though technological advances in this area, few studies are found concerning the action probiotics on protozoan, as Cryptosporidium parvum, an important intestinal parasite which causes one of the main opportunist infection in immunodeficient individuals, such as AIDS and transplanted patients. The probiotics products can be an alternative to treatment against cryptosporidiosis, since, so far an effective treatment against this infection has not been found. Therefore, the present study aimed to evaluate the action of strains of Lactobacillus plantarum, L. acidophillus and L. delbruekii, as a pool, on Cryptosporidium parvum in immunosuppressed mice. The experiments were developed using 42 animals separated in six groups: Control - the mices were not immunosuppressed, no infected and no treated; Immuno - immunosuppressed, no infected and no treated; No treated - immunosuppressed, infected and no treated; NTZ - immunosuppressed, infected and treated with a Nitazoxanide antimicrobial (150mg/kg); PRO - immunosuppressed, infected and treated with a preparation probiotic (3x10¹²UFC/mL); and, Preventive - immunosuppressed, treated with the probiotic preparation and then infected. After 12 days of immunosuppression procedure the animals were infected with 1,6x106 oocysts and, the respective treatments were started after five days of the inoculation of the oocysts. The infection was analyzed by counting of purified oocysts by tecnic of formol ether sedimentation of the feces. The intestinal colonization by lactobacilli was analyzed by pour plate technique on MRS agar containing Rifampicin antibiotic. The nutritional performance of the animals was calculated based on the rate of feed conversion, which is a relation between the amount of food consumed and the body weight gained by each animal. The results showed that the animals that received a preventive treatment with the probiotic preparation presented an elimination of oocysts lower than (P<=0,05) the other infected groups. The treatment with the probiotic preparation, post-infection also showed to be effective, once all the animals eliminated the infection. These results can be explained by competitive exclusion due to the colonization of gastrointestinal tract of the animals or by production of antimicrobial substances produced by Lactobacillus, which presented somehow any action on oocysts. It was also observed that the treated animals with the probiotic preparation presented better nutritional performance. These results confirm the hypothesis that the microorganisms which present probiotic properties represent an alternative way and promising, in the preventing and treatment of cryptosporidiosis.
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Gyürék, Lyndon Lester. "Ozone and chlorine inactivation of Cryptosporidium in water". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22990.pdf.
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Emelko, Monica Beata. "Removal of Cryptosporidium parvum by granular media filtration". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60533.pdf.
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Ali, Sayma. "The development of molecular methods for Cryptosporidium epidemiology". Thesis, Coventry University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418355.
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Nichols, Gordon L. "The biology, epidemiology and typing of Cryptosporidium spp". Thesis, University of Surrey, 1992. http://epubs.surrey.ac.uk/2235/.
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Pugh, Hedley James. "Deposition and adhesion of cryptosporidium oocysts on surfaces". Thesis, University College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300120.
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Stenger, Brianna Leigh Schneck. "Ecology of Cryptosporidium Parasites in Wild Rodent Populations". Diss., North Dakota State University, 2015. https://hdl.handle.net/10365/27278.
Texto completoResumen
Cryptosporidium is a genus of ubiquitous parasites that have been detected worldwide in nearly 500 species of amphibians, birds, fish, mammals, and reptiles. Most research has focused on the Cryptosporidium species and genotypes infecting humans and livestock, because of the public health significance and economic importance of the diarrheal disease cryptosporidiosis. Relatively little is known about Cryptosporidium-host dynamics in wildlife hosts, even though a wide range of wildlife species are susceptible to Cryptosporidium. Insights into ecology and host-parasite dynamics in wild populations are necessary to understand the biology and evolution of Cryptosporidium; to predict the emergence of human and livestock pathogens; and to clarify Cryptosporidium taxonomy and systematics. The focus of this research was to study the ecology of Cryptosporidium in populations of cricetid (voles, Peromyscus mice, muskrats) and sciurid (squirrels and chipmunks) rodents, and characterize Cryptosporidium taxa by sequencing multiple genetic loci (18S rRNA and actin genes). Paralogous copies of the 18S rRNA gene in Cryptosporidium genotypes from wild rodents were common and affected phylogenetic inferences. Eastern chipmunks (Tamias striatus) were infected with Cryptosporidium chipmunk genotype II, which had 18S rRNA gene paralogs that shared ~93% similarity. The degree of divergence has not been previously described in any Cryptosporidium taxa, but is similar to the divergence described in Plasmodium species, which have functionally distinct 18S rRNA gene copies. Marmotini squirrels were mainly host to novel Cryptosporidium genotypes, and to the best of our knowledge, we provide the first molecular characterization of Cryptosporidium in black-tailed prairie dogs (Cynomys ludovicianus). Cryptosporidium host adaptation and specificity was not evident in in Sciurini rodents and they were host to two zoonotic taxa, C. ubiquitum and Cryptosporidium skunk genotype. In conclusion, Cryptosporidium was prevalent in cricetid and sciurid rodents, and the extent of host adaptation varied among Cryptosporidium taxa as they are likely shaped by differences in host-parasite ecology and evolution. The rodents sampled are not significant reservoirs of zoonotic Cryptosporidium, with the exception of tree squirrels. Sequencing multiple genetic loci helped identify the presence of paralogs and resolve cryptic Cryptosporidium taxa, which strengthened phylogenetic inferences leading to a better understanding of Cryptosporidium systematics.USDA (project number: 2008-35102-19260)
NIH (project numbers: 2P20 RR015566, 1R15A1067284-01A1)
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Tabe, Ebot Sahidu. "Rhomboid Proteases and Surface Adhesins During Cryptosporidium Development". Diss., North Dakota State University, 2013. https://hdl.handle.net/10365/26889.
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Cryptosporidium parvum, a primary cause of cryptosporidiosis in humans and livestock
worldwide, has a complex life cycle that includes an environmental oocyst stage, and stages of
merogony, gametogony, and sporogony that are completed in a single host. Development
within the host takes place in a protected intracellular but extracytoplasmic niche at the apical
surface of epithelial cells. The life cycle can be described as having alternating extracellular
invasive and intracellular replicative stages. With no effective chemotherapeutics,
understanding the mechanism of host cell invasion by this pathogen is paramount.
The first aim dissertation was to identify functions of sporozoite surface proteins and
rhomboid proteases (CpROMs) during motility and invasion of host cells. We demonstrate that
two CpROMs distinctively and collectively cleaved five thrombospondin-family proteins
(TSPs) and a mucin-like glycoprotein in a heterologous assay. Further, there was differential
co-expression and co-localization of the CpROMs and their substartes during in vitro life cycle
development; CpROM4 and CpTSP10 proteins colocalized to the anterior, middle and posterior
of sporozoites and in developing intracellular stages while CpROM5 and TRAP-C1 colocalized
to intact and non-intact oocyst walls, the anterior of sporozoites, and intracellular stages as
early as 2 h post infection. CpTSP7, also localized to the oocyst wall, the anterior and posterior
of sporozoites and intracellular stages from 6 h post infection. Similar to CpTSP10, CpTSP9
was not present in the oocyst wall; however, it was expressed in sporozoites and intracellular
stages from 6 h post infection. Short synthetic peptides derived from adhesive ectodomains in
thrombospondins including a TRAP-C1 apple domain (TAAP), thrombospondin type I
domains in CpTSP7 (7TS) and CpTSP9 (9TS), and a kringle domain in CpTSP10 (10K1) as
well as their corresponding antibodies demonstrated competitive and neutralization inhibition effect of C. parvum infection of host cells. Polyclonal antibodies against TAAP caused
sporozoites to agglutinate in a concentration?dependent manner, suggesting a contribution to
reduced infectivity. In conclusion, the specificity and expression profiles of CpROM4 and
CpROM5 indicate that they have distinct functions in shedding surface adhesins during
excystation, motility, invasion, and intracellular development.
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Koh, Wan Hon. "The interaction of cryptosporidium with aquatic biofilm systems". Thesis, Koh, Wan Hon (2013) The interaction of cryptosporidium with aquatic biofilm systems. PhD thesis, Murdoch University, 2013. https://researchrepository.murdoch.edu.au/id/eprint/20253/.
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Cryptosporidium parvum is a common, opportunistic, diarrhoeal-causing, apicomplexan pathogen in humans, of which water is an important transmission vehicle. Recently, aquatic biofilms have been recognised as environmental reservoirs for the infective stage (oocysts) of Cryptosporidium, yet their fate after being trapped within biofilms is unknown. Previous cell-associated and cell-free studies have demonstrated, controversially, that Cryptosporidium may be able to multiply extracellularly, indicating that Cryptosporidium is not an obligate intracellular microorganism, and that the environment may play an important role in shaping its life cycle. Previously published data raise the question as to whether Cryptosporidium can survive and multiply within biofilms, resulting in an increase in numbers before release into water systems, leading to possible disease outbreaks.
This study, therefore, aimed to investigate the ability of biofilms to support Cryptosporidium multiplication. This was achieved using a combination of quantitative polymerase chain reaction (qPCR), flow cytometry (immunolabeled with Cryptosporidium oocysts-specific antibody), confocal microscopy (immunolabeled with Cryptosporidium developmental stage-specific antibody) and scanning electron microscopy (SEM) techniques. To mimic a water distribution system, Pseudomonas aeruginosa biofilm flow cell systems were established and unexcysted C. parvum oocysts were constantly supplied over a 6-day period. Prior to analysis, the four analytical methods were designed and empirically optimised according to the nature of the experimental sample studied.
Quantitative PCR results showed a significant increase (P<0.001) in Cryptosporidium as the biofilm matured, with the total number of C. parvum multiplying 2-3 fold during this period. Flow cytometry analysis also revealed that the captured oocysts had undergone excystation in biofilms, confirming that the increase in Cryptosporidium number was due to Cryptosporidium multiplication. From this, various Cryptosporidium developmental stages (sporozoites, trophozoites, meronts, and merozoites) were also identified from the biofilm using confocal microscopy and SEM. A correlative study using both SEM and confocal imaging determined that the observed developmental stages were Cryptosporidium, rather than degenerate/accumulated oocysts or yeast contamination. Furthermore, SEM analysis also revealed that Cryptosporidium may form a parasitophorous vacuole independently, potentially allowing it to complete its life cycle extracellularly. In addition, certain stages of the Cryptosporidium life cycle (trophozoites, meronts, and some previously undescribed gamonts) in biofilms were identified, and shown to closely resemble stages reported in the gregarine life cycle, emphasising the possibility that Cryptosporidium has inherited the capability to multiply extracellularly from their gregarine ancestor.
In conclusion, this study has successfully shown that biofilms can support Cryptosporidium multiplication in aquatic environments and thus, also demonstrated a role for biofilms in outbreaks and spreading of this disease. The generated results are novel, offering new insights into the role of biofilms in the C. parvum life cycle, providing additional information for water authorities, aiding in the control of Cryptosporidium and biofilm-contaminated drinking water.
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Korich, Dick Gary. "Cryptosporidium oocyst viability: Assessment and correlation with infectivity". Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186125.
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Outbreaks of cryptosporidiosis have been traced to Cryptosporidium oocysts in finished drinking water. Indeed, water contaminated with oocysts may be judged perfectly safe by conventional coliform tests. Although oocysts can be specifically identified using immunofluorescence, it is not yet possible to determine their viability. The lack of a viability test means that each oocyst detected in finished water must be regarded as potentially infective even though water treatment may have killed them. The goal of this research was to develop a test for oocyst viability. In vitro excystation, oocyst morphology, vital dyes, and a monoclonal antibody were tested. In vitro excystation expressed as percent of theoretical sporozoite yield correlated best with neonatal mouse infectivity. Although not directly applicable to testing water samples, excystation provided a basis for screening other testing methods. None of the eight vital dyes tested showed any relationship between oocyst staining and viability. This was presumably due to inability of the dyes to penetrate the oocyst wall. Pretreatment strategies designed to increase oocyst wall permeability were either ineffective or damaged the oocysts in ways that rendered them nonviable. Initially, microscopic appearance appeared to be related to oocyst infectivity. However, regression analysis showed that phase contrast microscopic appearance had marginal utility for use as a viability test. Indeed, microscopic identification of internal structures of intact oocysts is not a reliable viability indicator because DAPI staining showed intact sporozoite nuclei within obviously dead oocysts that would not excyst. A monoclonal antibody (MAb OW64) was found which binds to internal sites along the oocyst suture. There was positive correlation between binding of this MAb and decreasing oocyst infectivity indicating that MAb OW64 bound preferentially to nonviable oocysts. Regression analysis showed that OW64 binding overestimated oocyst viability because many nonviable oocysts did not bind the MAb. Nevertheless, MAb OW64 is a candidate for producing an immunofluorescence based test in which oocysts that bind OW64 are nonviable whereas those that do not bind are not necessarily viable. Before such a test can be recommended, however, the nonviability of oocysts that bind OW64 must be demonstrated by neonatal mouse infectivity using oocysts sorted by a fluorescence activated cell sorter.
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Sullivan-Madore, Mary 1959. "Detection of Cryptosporidium and Giardia in environmental waters". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/191916.
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Cryptosporidium and Giardia, both enteric parasites, have been shown to cause waterborne disease. Methods were developed to investigate the occurrence of Cryptosporidium and Giardia in large volumes of water. Environmental waters were filtered, eluted from a filter and concentrated using centrifugation. Antifoam was employed after homogenization of the resultant pellet suspension for faster oocyst recoveries. This suspension was then layered onto a density gradient to separate the parasites from the sediment. The gradient layer containing any potential parasites was directly labeled on the membrane filter with fluorescein labeled monoclonal antibodies. These filters were then examined by immunofluorescence. Using this technique, Cryptosporidium oocysts were detected in raw sewage, treated sewage, backflush waters, and surface waters. Cryptosporidium was three magnitudes higher in concentration than Giardia in raw sewage. Since Cryptosporidium is frequently present in environmental waters, and in significantly higher numbers than Giardia, it potentially could be transmitted by this route.
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Homem, Camila Guariz [UNESP]. "Avaliação da PCR em tempo real para detecção de Cryptosporidium parvum em amostras fecais de bezerros: Camila Guariz Homem. -". Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94592.
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A infecção por Cryptosporidium parvum em bovinos se manifesta como enfermidade subclínica ou com presença de morbidade e mortalidade, particularmente quando há associação com outros agentes infecciosos. Cryptosporidium parvum apresenta ainda grande importância em saúde pública. Este trabalho teve como objetivo o desenvolvimento da reação em cadeia da polimerase em tempo real (qPCR) para detecção de C. parvum em amostras fecais de bezerros e sua comparação com a reação em cadeia da polimerase (nested PCR), rotineiramente utilizada para diagnóstico de Cryptosporidium spp.. Duzentas e nove amostras fecais de bezerros entre um dia e seis meses de idade foram examinadas pela qPCR para amplificação de fragmentos do gene da actina e pela nested PCR para o gene da subunidade 18S do rRNA. A qPCR apresentou positividade para C. parvum em 73,21% (153/209) das amostras, enquanto a nested PCR apresentou amplificação positiva para Cryptosporidium spp. em 56,5% (118/209) das amostras. A sensibilidade analítica da qPCR foi de aproximadamente um oocisto de C. parvum. Não se observou amplificação inespecífica de DNA Cryptosporidium bovis, Cryptosporidium andersoni, Cryptosporidium ryanae, Cryptosporidium canis, Cryptosporidium serpentis, Cryptosporidium galli, Cryptosporidium baileyi e Cryptosporidium genótipo II de aves. Desta forma, conclui-se que a qPCR para o gene da actina é uma técnica sensível e específica para detecção de C. parvum em amostras fecais de bezerros
The infection with Cryptosporidium parvum in cattle results in subclinical disease or in the presence of morbidity and mortality, particularly when associated with other infectious agents. This species is also an important public health problem. The aim of this research was to develop a real time polymerase chain reaction (qPCR) for detection of C. parvum DNA in fecal samples of calves, in comparison to a nested PCR routinely used for Cryptosporidium spp. diagnosis. Two hundred and nine fecal samples from calves aged between one day and six weeks were screened by qPCR specific for the actin gene of C. parvum and using nested PCR targeting the 18S rRNA gene of Cryptosporidium spp.. The qPCR showed positivity for C. parvum in 73,21% (153/209) of the samples, and nested PCR was positive for Cryptosporidium spp. in 56.5% (118/209) of the samples. The analytical sensitivity of qPCR foi de aproximadamente one oocyst C. parvum per reaction tube. Evaluation of analytical specificity did not reveal inespecific amplification for DNA of the following Cryptosporidium species and genotypes: C. bovis, C. andersoni, C. ryanae, C. canis, C. serpentis, C. galli, C. baileyi and avian genotype II. These results allowed the conclusion that qPCR for actin gene is a sensitive and specific technique for detection of C. parvum in fecal samples from calves
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Santos, Samuel Ricardo dos 1980. "Fluorescência retardada em protozoários : Giardia intestinalis e Cryptosporidium parvum". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257131.
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Orientadores: José Euclides Stipp Paterniani, Cristiano de Mello GallepTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola
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Resumo: Giardia spp. e Cryptosporidium spp. são organismos desafiadores em monitoramento ambiental, podendo afetar os seres humanos e os animais com grandes impactos na saúde pública. Métodos para detectar esses organismos são descritos na literatura ¿ p.ex.: o método EPA 1623.1. No entanto, muitos não são capazes de detectar a viabilidade destes parasitos. Este trabalho avaliou o uso de marcadores fluorescentes combinados com a técnica de detecção de fluorescência retardada na detecção de viabilidade de Giardia intestinalis e Cryptosporidium parvum. Testes de incubação com 6-carboxifluorceina-succinimidil-diacetato-éster (CFDA-SE), C12-resazurina e SYTOX Green foram desenvolvidos com cistos de G. intestinalis e oocistos de C. parvum. Medidas de fluorescência retardada em câmara escura projetada e em dispositivo comercial foram aplicados em amostras purificadas e concentradas de G. intestinalis após incubação com CFDA-SE. Grupos contendo cistos vivos e infecciosos, mortos a 100° C, estressados com luz UV-C e envelhecidos foram analisados via fluorescência retardada e microscopia de epifluorescência em oito séries experimentais. Os resultados demonstram que (oo)cistos vivos e infecciosos não são marcados com os marcadores fluorescentes. Dupla marcação em (oo)cistos mortos é observada após 30 minutos de incubação com C12-resazurina 5,0 ?M e SYTOX Green 100 nM. (Oo)cistos mortos apresentam marcação verde após incubação de CFDA-SE 5,0 ?M. O envelhecimento da amostra foi acompanhado pelo aumento da taxa de marcação celular com cistos apresentando ~50% de marcação aos 30 dias de idade e ~100% aos 50 dias de idade. Testes com fluorescência retardada demonstram que cistos vivos e com idade inferior a 20 dias apresentam intensidades superiores aos cistos mortos e estressados após excitação com 365 nm. A excitação com 365 nm apresentou correlação R2 > 95% após análise de cinética de decaimento com modelo exponencial de segunda ordem. Os dados indicam que o decaimento da fluorescência retardada é acompanhado por duas componentes k1 e k2 onde k2 = 5?k1, estando estas conectadas com as condições fisiológicas da Giardia. O procedimento pode ser efetuado em 10 passos laboratoriais em aproximadamente 60 minutos de análise. A fluorescência retardada apresenta futuro promissor na análise de viabilidade de parasitos em amostras purificadas
Abstract: Giardia spp. and Cryptosporidium spp. are challenging and important organisms in modern environmental monitoring. These protozoa can affect humans and animals seriously, as reflection of sanitation problems in water quality control, with huge impact over economics and public health. Methods to detect such organisms are well described in literature - i.e. the EPA Method 1623.1 and AWWA 2012. But those ones are not able to detect infectivity. For that, the usual procedures include infection of animal model leading to at least one week for confirming infectivity. Some research with dye probes are being developed in order to provide useful, reliable and low cost procedures for detection of protozoa viability, i.e. enabling to distinguish dead samples cells from living ones. This work describes the screening tests for viability detection of protozoa samples - Giardia intestinalis and Cryptosporidium parvum - using carboxifluorcein-succinimidyl-diacetate-ester (CFDA-SE), C12-resazurin and SYTOX Green. Living, heat-killed and UV-C stressed (oo)cysts were analyzed using these chemical probes. G. intestinalis in concentrated samples and stained with CFDA-SE were analysed by fluorescence imaging as well as by delayed fluorescence (DF) after UV-A and white-light excitation. The weak DF profiles were detected in photon-counting setups, in 8 series of tests for intact, for heat-killed and for UV-C-stressed samples are shown. Results show that fresh, i.e. living and viable (oo)cysts cannot be stained by the mentioned neither with CFDA-SE nor C12-resazurin and SYTOX Green dyes. Double-marked (oo)cysts are observed when C12-resazurin and SYTOX Green are applied to old cysts as well to dead ones. Aged samples show increasing number of stained organisms: 30-day-old with ~50% while samples older than 50 days with almost 100% marked. Intact samples present stronger fluorescence and DF than the stressed ones, with good replication after UV-A excitation. After excitation @365nm samples present DF better fitted by double exponential decay kinetics, with the decay constant k2 five times higher than the k1 constant. The procedure can be easily reproduced in 10 steps, taking around 1h of laboratorial work with purified samples
Doutorado
Agua e Solo
Doutor em Engenharia Agrícola
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Liyanage, Lalith R. J. "Chlorine dioxide inactivation of Cryptosporidium parvum oocysts in water". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/NQ29064.pdf.
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Das, Rony. "Cryptosporidium detection through antibody immobilization on a solid surface". Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/28932.
Texto completoResumen
Current detection of pathogenic organisms in water relies on the use of indicators (turbidity, Escherichia coli, total coliforms, fecal coliforms etc.) or time consuming assays that can only be done in a specialized laboratory. In this research a simple assay was developed for rapid and sensitive recovery and identification of waterborne pathogens from environmental samples. The assay developed involves capturing target pathogens onto an activated capture surface, exposing the capture surface to antibody conjugated micro-retroreflectors, and then inserting the capture surface into an inexpensive, simple reader to detect the retroreflection signal to confirm the presence of target pathogens.
Antibody (capture molecule: IgG and IgM) fragments specific to Cryptosporidium, as a model waterborne pathogen, were produced and immobilized site specifically and randomly onto gold-coated surfaces as well as corner cube micro-retroreflectors (ccμRR). A shear test performed to determine the critical shear stress that antigen-antibody bonds are able to endure showed that the organism-antibody bond could resist up to a shear stress of 126 dyne/cm2 and beyond this critical value immobilized Cryptosporidium oocysts were lost from the system. Capture tests were designed to determine the optimum operating conditions of the parallel flow sampling device using IgG-Fab', IgG-Fab, and IgM-Fab' activated surfaces. Capture efficiencies did not differ significantly within the range of flow rate used (14 – 42 mL/min), but improvement was noticed when the cell depth was decreased from 250 μm to 125 μm. Site specifically oriented IgG-Fab' activated surfaces resulted in significantly better capture efficiencies than surface with randomly immobilized IgG-Fab fragments. The capture efficiency of IgG-Fab' activated surfaces was significantly different than that of IgM-Fab' immobilized surfaces. There was no significant difference in capture efficiency using the surfaces activated with dilutions (1:8, 1:4, 1:2, and 1:1.5) of antibody fragments originally made of 500μg of IgG1 antibody. The use of BSA as a blocking agent improved the reproducibility of the capture efficiency. CcμRR were suspended in solution and activated with IgG-Fab' to use as a recognition molecule. The current set up of the detector system is capable of detecting the presence and absence of a large number of ccμRR attached on the solid surface.
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Hardy, Scott Andrew. "Effectiveness of static mixers for disinfection of cryptosporidium oocysts". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/20925.
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Pedraza-Diaz, Susana. "Molecular characterisation of cryptosporidium species involved in human infection". Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248120.
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Mtambo, Mkumbukwa Madundo Angelo. "Cryptosporidium infection in cats : epidemioloigy and cross transmission studies". Thesis, University of Glasgow, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384860.
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Marshall, James Spencer. "Cryptosporidium parvum : detection and distribution in two Yorkshire rivers". Thesis, University of Leeds, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390895.
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Moriarty, Elaine Maria. "The detection and persistance of Cryptosporidium during beef processing". Thesis, University of Ulster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288825.
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Mead, Jan Renee. "Cryptosporidium: Isolate variation and humoral responses to sporozoite antigens". Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184391.
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The humoral response of humans, calves and horses to Cryptosporidium sporozoite antigens was evaluated using a western blot technique. Sera from calves, humans and horses were obtained at various times following the detection of infection. Sera were reacted with detergent-solubilized, sporozoite antigens form sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The number of antigens recognized by immune sera from humans and animals increased with time post infection (P.I.). A 20 kDa antigen appeared to be a major sporozoite surface determinant since it was labelled via membrane protein biotinylation and recognized by mouse monoclonal antibodies using indirect immunofluorescence and western blotting. Detectable recognition of the 20 kDa band occurred in 3 week post infection (P.I.) sera from all species tested. Sera reactivity to the 20 kDa band diminished significantly within 5 months P.I. when infected humans had no further recurrence of cryptosporidial diarrhea. In contrast, 12 month P.I. sera from an individual constantly exposed to oocysts under working conditions was as strongly reactive as the 3 week convalescent sera. Therefore, reactivity to the 20 kDa antigen appeared to be a good indicator of exposure to Cryptosporidium. Anti-sporozoite indirect immunofluorescent titers decrease in reactivity from convalescent to post convalescent sera which correlated with western blot results. Chromosomal DNA of five Cryptosporidium parvum isolates and one Cryptosporidium baileyi isolate were compared by field inversion gel electrophoresis (FIGE). FIGE analyses of parasite DNA prepared from purified sporozoites versus intact oocysts showed no observable differences. Chromosomal DNA migration patterns of the five Cryptosporidium parvum isolates were indistinguishable. Distinct differences in chromosomal DNA were evident between the Cryptosporidium baileyi and Cryptosporidium parvum isolates, yet the overall pattern was similar. Five C. parvum isolates were also compared using two dimensional electrophoretic analyses. Silver stained patterns of sporozoite proteins showed a shift in a 106 kDa protein in three of the isolates. One isolate (Mexico) showed a complete absence of this protein (106 kDa) and the presence of an additional 40 kDa protein not found in any other isolate.