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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Papel Protetor do Gene Humano APOE4 em Camundongos TransgÃnicos Submetidos pela DesnutriÃÃo e InfecÃÃo pelo Criptosporidium parvum / Paper Protector Gene in Human APOE4 Mice Submitted by Malnutrition and Infection Cryptosporidium parvum

Orleancio Gomes Ripardo de Azevedo 10 October 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O ciclo vicioso de doenÃas entÃricas na infÃncia à um problema de saÃde pÃblica com consequÃncias graves e seus efeitos no desenvolvimento infantil nÃo estÃo totalmente elucidados. Orià e colaboradores, em 2005, demonstraram que crianÃas portadoras do gene APOE 4 com alta morbidade de diarreia apresentavam um melhor desempenho em testes cognitivos. O objetivo desse trabalho foi avaliar o papel protetor do gene APOE 4 em camundongos C57BL6J submetidos à desnutriÃÃo induzida por uma raÃÃo pobre em proteÃna (2%) e pela infecÃÃo intestinal induzida pelo Criptosporidium parvum. Utilizamos camundongos C57BL6J machos com peso mÃdio de 14 g, submetidos a um perÃodo de 14 dias de desnutriÃÃo e a 7 dias de infeÃÃo por C. parvum meio por meio da gavagem de 107 oocistos. Os animais foram separados segundo o genÃtipo: wildtype, APOE nocaute (ApoE Ko), APOE 3/3 (com gene APOE 3 humano) e APOE 4/4 (com gene APOE 4 humano). Os animais controles receberam PBS via gavagem. O peso dos animais foi monitorado diariamente. Os camundongos foram sacrificados em cÃmara de CO2 seguido de deslocamento cervical apÃs 14 dias do inÃcio do protocolo. Durante o perÃodo de pÃs-infecÃÃo foram coletadas as fezes dos animais infectados em dias alternados, para a realizaÃÃo do PCR quantitativo em tempo real (qPCR) para a anÃlise da quantidade de C. parvum liberada nas fezes. Amostras de Ãleo foram congeladas em nitrogÃnio lÃquido e armazenadas em freezer a -80ÂC para as anÃlises moleculares. Outras amostras foram fixadas em paraformaldeÃdo tamponado (4%) para processamento histolÃgico. Foram avaliados os parÃmetros morfomÃtricos de altura de vilo e profundidade de cripta nos segmentos ileais. Para a detecÃÃo de citocinas prÃinflamatÃrias de interesse (IL-1&#946;, IFN- &#947;, TNF-&#945; e IL-17), utilizou-se o ensaio multiplex (Luminex xMAP). Ainda por qPCR avaliou-se o transportador catiÃnico de aminoÃcidos (CAT-1), arginase 1, iNOS e TLR9. No peso encontramos uma maior adaptaÃÃo a perda de peso nos animais APOE 4 no 2o e 3o dias de desnutriÃÃo em comparaÃÃo a todos os grupos (p<0,05). No perÃodo de pÃs-infecÃÃo verificou-se diferenÃa significante no 2o dia (p<0,05) em comparaÃÃo a todos os grupos. Nas anÃlises morfomÃtricas, encontramos uma reduÃÃo na altura de vilos e profundidade de criptas nos animais APOE nocautes, jà nos animais APOE 4/4 ocorreu uma proteÃÃo contra esses danos em comparaÃÃo a todos os grupos (p<0,05). Os dados da anÃlise de liberaÃÃo de oocistos nas fezes evidenciaram um aumento do estado prÃ-inflamatÃrio e antiparasitÃrio nos animais APOE Ko e APOE 4/4, verificado por meio de uma reduÃÃo na quantidade de C. parvum liberado nas fezes de maneira significativa. Houve um aumento dos nÃveis intestinais das citocinas prÃ-inflamatÃrias IL-1&#946; (p<0,05) nos animais APOE Ko desnutridos e infectados em comparaÃÃo com APOE3/3 e APOE4/4, e altos nÃveis de IFN-&#947; (p<0,05) em comparaÃÃo com os controles selvagens e o grupo APOE Ko desnutrido controle. Os animais desnutridos controles APOE Ko tiveram aumento dos nÃveis intestinais de IL-17 (p<0,05) quando comparados aos animais APOE Ko desnutridos infectados. Dados de qPCR evidenciam que a presenÃa do genÃtipo APOE4 em camundongos aumenta os transcritos primÃrios de CAT-1 e arginase - 1 no Ãleo em relaÃÃo aos selvagens, APOE Ko e APOE3 (p<0,05) e que os animais nocautes aumentaram a expressÃo de iNOS em relaÃÃo aos outros grupos (p<0,05). Os animais APOE 4 desnutridos e infectados apresentaram uma expressÃo significativamente aumentada nos nÃveis de mRNA para TLR9 no Ãleo comparado com os APOE Ko igualmente desafiados (p<0,05). A partir dos nossos achados, podemos concluir que o animais com genÃtipo APOE 4 possuem uma aÃÃo prÃ-inflamatÃria controlada, o que favorece o combate ao C. parvum, visto que reduz a quantidade de DNA do parasita liberado nas fezes e melhora a taxa de crescimento de animais submetidos pela desnutriÃÃo/infecÃÃo, sugerindo que hospedeiros com genÃtipo APOE 4 possuem uma maior proteÃÃo contra as alteraÃÃes intestinais induzidas pela combinaÃÃo de C. parvum e desnutriÃÃo. / The vicious cycle of enteric infections and malnutrition during childhood is a major public health problem with devastating consequences and its effects are not fully elucidated. Oria and colleagues in 2005 showed that children with heavy diarrhea burdens when carrying the APOE 4 gene had a better cognitive performance. The aim of this study was to evaluate the protective role of APOE 4 gene in C57BL6J mice challenged by malnutrition induced by a 2% protein diet and intestinal infection caused by Cryptosporidium parvum. We used male C57BL6J mice weighing in average 14g, challenged by malnutrition for a period of 14 days compound with 7 days of C. parvum infection through a single dose of 107 oocysts given by gavage. Study animals were separated according to their genotype, as following: wild-type, APOE knock-out, APOE 3/3 (carriers of the human APOE 3 gene) and APOE 4/4 (carriers of human APOE 4 gene). Control animals received PBS by gavage. Body weight of the animals was monitored daily. Mice were sacrificed in CO2 chamber with posterior cervical dislocation after 14 days from the beginning of the protocol. During the post-infection period, stools samples were collected from the infected mice every other day for real time quantitative PCR (qPCR) assays in order to quantify C. parvum oocysts released in the stools. Ileal samples were immediately frozen in liquid nitrogen and then stored in a freezer at -80ÂC for molecular analyses. Other samples were fixed in buffered paraformaldehyde (4%) for histological processing. Morphometric parameters were evaluated for villus height and crypt depth in the ileal segments. For detection of a proinflammatory cytokine panel (IL- 1&#946;, IFN-&#947;, TNF-&#945;, and IL-17), we used the multiplex assay (Luminex xMAP). In addition by qPCR, the cationic amino acid transporter (CAT-1), arginase 1, iNOS, and TLR9 were assessed. Regarding weight, we found a greater adaptation to weight loss in APOE 4 animals in the 2nd and 3rd days of malnutrition (p<0.05) and in the postinfection time there was a significant difference on the 2nd day (p<0.05) compared to all groups. In the morphometric analyses, we found villus blunting and crypt disorganization in APOE knockout mice. We found APOE 4 protection against these alterations compared to all groups (p<0.05). The C. parvum oocyst shedding data indicate an increase in the pro-inflammatory state and anti-parasitic effects seen in the APOE Ko and APOE 4/4 mice, as confirmed by a significant reduction of the C. parvum released in the stools. In addition, we found increased levels of the intestinal pro-inflammatory cytokine (IL-1&#946;) (p<0.05) in the APOE Ko when compared with APOE3/3 and APOE4/4, higher levels of IFN-&#947; (p<0.05) when compared with wild-type and undernourished APOE Ko controls. The APOE Ko undernourished mice have increased intestinal levels of IL-17 compared with APOE Ko undernourished infected mice. qPCR data demonstrate that the presence of the APOE4 genotype in mice increased the primary transcripts of CAT-1 and arginase 1 in comparison to wild types, APOE Ko, and APOE 3/3 (p<0.05). Furtermore, APOE knockout mice had higher iNOS expression in comparison to all groups (p<0.05). The APOE 4 mice showed significant increase in the expression of TLR9 mRNA in the ileum when compared to APOE Ko mice (p<0.05). Altogether we concluded that the APOE 4 carriers have a balanced pro-inflammatory response, benefiting the C. parvum control, as seen by reduction of the parasite DNA released in the stools, and by improvements in the growth rates in the mice challenged malnutrition/infection, suggesting that the hosts carrying the APOE4 genotype have a better protection against the intestinal alterations induced by the compound challenge of C. parvum infection and malnutrition.
2

Vliv skladovacího média, teploty a času na uchovávání vzorků trusu pro následnou detekci vybraných zoonotických protist pomocí PCR metod / Effect of storage media, temperature, and time on preservation fecal symples containing selcted zoonotic protist for PCR analysis

HAVRDOVÁ, Dita January 2014 (has links)
Resting stages of parasites are very well resistant to adverse effects of the external environment. They have the ability to survive for long periods and to accommodate to such effects. One of the accurate methods for detection of C. parvum and E. cuniculi is PCR. As the most appropriate storage medium for the droppings collected in the field is recommended RNA later and 2,5 % potassium dichromate. Samples fixed in this way may be stored at temperatures ranging from -20 to 21 °C, event if there is no possibility of storing them in a refrigerator.
3

Remoção de Giardia spp. e Cryptosporidium spp. em águas de abastecimento com turbidez elevada utilizando cloreto de polialumínio: estudo em escala de bancada e desafios analíticos / Giardia spp. Cysts and Cryptosporidium spp. Oocysts removal in high turbid drinking water using polyaluminum chloride: a bench scale study and analytical challenges

Maciel, Paulo Marcos Faria 22 August 2014 (has links)
O objetivo deste trabalho foi avaliar o desempenho da remoção de cistos deGiardia spp. e oocistos de Cryptosporidium parvum, em águas de abastecimento com turbidez elevada, em experimentos em escala de bancada (coagulação, floculação, decantação e filtração). Para tanto, empregou-se o coagulante cloreto de polialumínio &#8211; PAC. O método de filtração em membranas foi adotado para a concentração de protozoários, seguido ou não da etapa de purificação por separação imunomagnética &#8211; IMS. Os métodos foram avaliados em experimentos de controle de qualidade analítica e o método sem IMS apresentou as seguintes porcentagens de recuperação, 80% ±16,32% para cistos de Giardia spp. e 5% ±10,00% para oocistos de C. parvum. O método com IMS apresentou 31,5%±7,55% de recuperação para cistos de Giardia spp. e 5,75%±3,20% de recuperação para oocistos de C. parvum. Os experimentos demonstraram que não houve melhora na remoção de ambos os protozoários na condição de maior dosagem de coagulante (65 mg.L-1 de PAC e pH 7,29). A condição de menor dosagem de coagulante (25 mg.L-1 de PAC e pH 6,76) apresentou um desempenho melhor, ao contrário de uma expectativa de que a maior dosagem de coagulante pudesse favorecer a remoção destes microrganismos. A condição de menor dosagem apresentou, na água filtrada, 50 e 75% de ausência de identificação de cistos de Giardia e oocistos de C. parvum, respectivamente. A condição de maior dosagem apresentou (oo)cistos na água filtrada de todas amostras analisadas. Estes resultados indicam a importância do controle da coagulação na remoção de protozoários. / The aim of this study was to evaluate the performance of Giardia spp. cysts and Cryptosporidium parvum oocysts removal in a bench scale experiment. The coagulant polyaluminium chloride &#8211; PACl was used in this research. The protozoa concentration tests were performed by applying the Membrane Filtration method, with and without Immunomagnetic Separation assay-IMS. The methods were evaluated using control experiments and the method without IMS had the following percentage recovery, 80% ± 16.32% and 5% ±10.00% for Giardia cysts and C. parvum oocysts, respectively. The method with IMS presented 31.5% ± 7.55% and 5.75% ± 3.20% of percentage recovery for Giardia cysts and C. parvum oocysts, respectively. Bench scale experimental results have clearly shown that there was no improvement in protozoa removal using the superior dosage of coagulant. The inferior dosage condition (25 mg.L-1 of PACl and pH 6,76) performed better, which was contrary to what was expected in which a superior dosage of coagulant could favour when removing microorganisms. The inferior dosage condition presented 50% and 75% of absence of Giardia cysts and C. parvum oocysts in the final water, respectively. The second coagulation condition (65 mg.L-1 of PACl and pH 7,29) presented protozoa (oo)cysts in the final water of all the samples examined. These results indicate the importance of coagulation control in protozoa removal.
4

Remoção de Giardia spp. e Cryptosporidium spp. em águas de abastecimento com turbidez elevada utilizando cloreto de polialumínio: estudo em escala de bancada e desafios analíticos / Giardia spp. Cysts and Cryptosporidium spp. Oocysts removal in high turbid drinking water using polyaluminum chloride: a bench scale study and analytical challenges

Paulo Marcos Faria Maciel 22 August 2014 (has links)
O objetivo deste trabalho foi avaliar o desempenho da remoção de cistos deGiardia spp. e oocistos de Cryptosporidium parvum, em águas de abastecimento com turbidez elevada, em experimentos em escala de bancada (coagulação, floculação, decantação e filtração). Para tanto, empregou-se o coagulante cloreto de polialumínio &#8211; PAC. O método de filtração em membranas foi adotado para a concentração de protozoários, seguido ou não da etapa de purificação por separação imunomagnética &#8211; IMS. Os métodos foram avaliados em experimentos de controle de qualidade analítica e o método sem IMS apresentou as seguintes porcentagens de recuperação, 80% ±16,32% para cistos de Giardia spp. e 5% ±10,00% para oocistos de C. parvum. O método com IMS apresentou 31,5%±7,55% de recuperação para cistos de Giardia spp. e 5,75%±3,20% de recuperação para oocistos de C. parvum. Os experimentos demonstraram que não houve melhora na remoção de ambos os protozoários na condição de maior dosagem de coagulante (65 mg.L-1 de PAC e pH 7,29). A condição de menor dosagem de coagulante (25 mg.L-1 de PAC e pH 6,76) apresentou um desempenho melhor, ao contrário de uma expectativa de que a maior dosagem de coagulante pudesse favorecer a remoção destes microrganismos. A condição de menor dosagem apresentou, na água filtrada, 50 e 75% de ausência de identificação de cistos de Giardia e oocistos de C. parvum, respectivamente. A condição de maior dosagem apresentou (oo)cistos na água filtrada de todas amostras analisadas. Estes resultados indicam a importância do controle da coagulação na remoção de protozoários. / The aim of this study was to evaluate the performance of Giardia spp. cysts and Cryptosporidium parvum oocysts removal in a bench scale experiment. The coagulant polyaluminium chloride &#8211; PACl was used in this research. The protozoa concentration tests were performed by applying the Membrane Filtration method, with and without Immunomagnetic Separation assay-IMS. The methods were evaluated using control experiments and the method without IMS had the following percentage recovery, 80% ± 16.32% and 5% ±10.00% for Giardia cysts and C. parvum oocysts, respectively. The method with IMS presented 31.5% ± 7.55% and 5.75% ± 3.20% of percentage recovery for Giardia cysts and C. parvum oocysts, respectively. Bench scale experimental results have clearly shown that there was no improvement in protozoa removal using the superior dosage of coagulant. The inferior dosage condition (25 mg.L-1 of PACl and pH 6,76) performed better, which was contrary to what was expected in which a superior dosage of coagulant could favour when removing microorganisms. The inferior dosage condition presented 50% and 75% of absence of Giardia cysts and C. parvum oocysts in the final water, respectively. The second coagulation condition (65 mg.L-1 of PACl and pH 7,29) presented protozoa (oo)cysts in the final water of all the samples examined. These results indicate the importance of coagulation control in protozoa removal.
5

Development and application of integrated ozone contactor design and optimization tools

Kim, Doo-Il 18 May 2007 (has links)
Novel integrated ozone contactor design and optimization tools which consist of an instrument that measures ozone decay kinetics, a program that performs predictive simulation, and an experimental method to examine mixing characteristics within the ozone contactor, were developed in this study. A multi-channel stopped-flow reactor (MC-SFR) is an instrument that performs automatic, real-time, and continuous analysis of ozone decay kinetics in natural waters. Ozone Contactor Model (OCM) is the software to simulate the performance of full-scale ozone bubble-diffuser contactors in support of current and future regulations regarding pathogen and bromate control in drinking water. The MC-SFR and OCM developed in this study were further applied to simulate Cryptosporidium parvum oocyst log inactivation and bromate formation in Linnwood Water Plant Ozone Facility (LWPOF) at Milwaukee Water Works, Milwaukee, WI and model predictions were verified with experimental results. Three dimensional laser induced fluorescence(3DLIF) allowed real time characterization of mixing conditions in a physical model ozone contactors by capturing fluorescence image emitted from a laser dye (i.e. Rhodamine 6G) using a high speed CCD camera. 3DLIF system was applied to analyze the hydrodynamics of two representative types of ozone contactor: direct discharge side-stream venturi injector (SVI) and multi-chambered fine bubble diffuser (FBD). Experimental results verified the presence of circulative swirling related for low dispersion for SVI reactor and the existence of non-ideal flow including short circuiting and internal recirculation in FBD reactor. Finally, integrated tools were applied to the design of a new ozone contactor under planning stage to assess current design and to recommend the improvement.

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