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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.
161

Estudo quantitativo da infecção por Babesia bovis em bovinos de corte de diferentes grupos genéticos

Giglioti, Rodrigo [UNESP] 25 November 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-11-25Bitstream added on 2014-06-13T19:42:44Z : No. of bitstreams: 1 000749443.pdf: 1003234 bytes, checksum: 782cda03d91059640e363de67ccc1519 (MD5) / A babesiose bovina é uma hemoparasitose transmitida pelo carrapato Rhipicephalus (Boophilus) microplus que causa grandes prejuízos à bovinocultura do Brasil. Entre as espécies que causam as babesioses bovinas, B. bovis se destaca como a mais patogênica. É amplamente conhecida a resistência natural dos bovinos do grupo genético Bos taurus indicus frente a B. bovis. Entretanto, a relação quantitativa do nível de infecção em animais Bos taurus taurus e seus cruzamentos é desconhecida. O método clássico de detecção e quantificação da parasitemia por B. bovis apresenta baixa sensibilidade e falha no diagnostico em animais portadores. Recentemente, a técnica de qPCR tem sido utilizada com grande sucesso para este propósito. Assim, o presente estudo teve como objetivo verificar a associação entre o nível de infestação por R. (B.) microplus, a soroprevalência e a parasitemia por B. bovis, estimada através dos métodos do ELISA-teste e qPCR em bovinos de corte naturalmente infestados, de diferentes locais e grupos genéticos (grupos-locais).Verificou-se que a infestação por carrapatos foi maior nos grupos locais de taurinos, com diferenças significativas entre os grupos. Nos ensaios do ELISA-teste, 74,39% dos animais avaliados foram positivos, encontrando-se os maiores níveis de anticorpos em animais taurinos quando comparados aos cruzados. Nas quantificações do DNA através da qPCR, a técnica demonstrou alta sensibilidade analítica e todos os animais foram positivos. Foram verificadas diferenças significativas (P<0,05) para o numero de copias (NC) de DNA de B. bovis entre os grupos locais, onde o grupo Angus de José Bonifácio, SP (AJB) apresentou o maior nível de infecção. As repetibilidades encontradas para as contagens de R. (B.) microplus e os NC de DNA de B. bovis foram baixas, enquanto que para os níveis de anticorpos obtidos pelo ELISA-teste foram... / Bovine babesiosis is a tick-borne disease, transmitted by Rhiphicephalus (Boophilus) microplus tick, that imposes substantial economic losses in to Brazilian livestock, among the species that cause bovine babesiosis B. bovis is the most virulent. Is widely known the natural resistance of the Bos taurus indicus genetic group to B. bovis, however, the quantitative relationship of the infection levels when compared to Bos taurus taurus and their crosses is unknown. The classical detection and quantitation method is of low sensitivity and usually fails to diagnose carrier animals. Recently, the real-time PCR (qPCR) techniques have been used successfully for these purposes. The present study aimed to determine the association among infestations by R. (B.) microplus, infection levels by B. bovis, estimated by qPCR, and the antibody levels in beef cattle naturally infested, proceeding of different locations and genetic groups (local groups). It was found greater tick infestations in taurine local groups, with significant differences between groups. In the ELISA test, 74.39% of animals were positive, meeting the highest antibodies levels in taurine animals when compared to the crossbred. In the DNA quantification, the analytical sensitivity of qPCR technique was high and all animals were positive. There were significant differences (P <0.05) for the DNA copy number (NC) among local groups, where Angus-Jose Bonifácio group (AJB) showed the highest infection levels. R. (B.) microplus scores and DNA copy number of B. bovis show low repeatability, whereas the antibodies levels were higher. No correlation among the examined measures were found. It is concluded that there is variation in the seroprevalence and DNA copy number of B. bovis among different local groups and the antibodies levels in the animals is not directly associated with the DNA NC of B. bovis, and both are independent of tick infestation
162

Ocorrência de Cryptosporidium spp. em crianças e seus respectivos cães e gatos de estimação no município de Andradina, SP

Coelho, Natalia Marinho Dourado [UNESP] 14 December 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-14Bitstream added on 2014-06-13T19:35:11Z : No. of bitstreams: 1 coelho_nmd_me_araca.pdf: 406925 bytes, checksum: b4d17da85b8093f899383793bd8d1c81 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / O objetivo deste estudo foi avaliar a ocorrência de Cryptosporidium spp. em crianças e seus respectivos cães e gatos de estimação residentes no Município de Andradina, SP, por meio do Teste de Imunoadsorção Enzimática (ELISA). Durante o período de janeiro a agosto de 2009, foram analisadas 188 amostras fecais de crianças, bem como de seus respectivos cães e gatos de estimação para pesquisa de Cryptosporidium spp. O teste quiquadrado (χ2) foi utilizado para verificar a associação entre as variáveis: sexo, idade, raça e consistência fecal, com nível de significância de 5%. Pelo ELISA foi detectado Cryptosporidium spp. em em amostras fecais de 2,1% (4/188) das crianças com idade inferior a sete anos. Entre os animais examinados, 6,8% (9/132) dos cães e 5,4% (3/56) felinos apresentaram amostras positivas para este coccídeo. Tanto nas crianças como nos animais não houve influencia do sexo e da idade na detecção do Cryptosporidium spp. sendo que nestes últimos a raça também não influenciou (P> 0,05). Neste trabalho foi evidenciada uma baixa ocorrência deste parasito nas crianças, assim só será possível determinar com precisão a relação entre a infecção das crianças com dos animais, com a posterior caracterização molecular deste protozoário. / The objective this study was to evaluate the occurrence of Cryptosporidium spp. in children and their dogs and pet cats in the city of Andradina, SP. through Test-linked immunosorbent assay (ELISA), during the period from January to August 2009, we analyzed 188 fecal samples from children, as well as their dogs and pet cats for detection of Cryptosporidium spp. The chi-square test (χ2) was used to verify the association between gender, age, race and fecal consistency, with a significance level of 5%. Using ELISA was detected Cryptosporidium spp. in stool samples in 2.1% (4/188) of children under the age of seven years. Among the animals examined, 6.8% (9/132) of dogs and 5.4% (3/56) cats had positive samples for this coccidium. Both children and animals there was no influence of sex and age on the detection of Cryptosporidium spp. being that in these last race did not influence (P> 0.05). This study demonstrated a low occurrence of this parasite in children, so only you can accurately determine the relationship between the infection of children with the animal with the molecular characterization of this parasite.
163

Prevalência da língua azul em ovinos da região de Araçatuba - São Paulo, Brasil /

Nogueira, Adriana Hellmeister de Campos. January 2008 (has links)
Orientador: Tereza Cristina Cardoso Silva / Banca: Maria Cecília Rui Luvizotto / Banca: Edviges Maristela Pituco / Resumo: A língua azul é uma doença viral, cujo agente etiológico pertence à família Reoviridae, gênero Orbivírus, transmitida por um vetor (artrópode) hematófago, do gênero Culicoides. Por se tratar de doença confundível com Febre Aftosa está incluída na lista de diagnóstico diferencial juntamente com Estomatite Vesicular, Varíola Ovina, Ectima Contagioso. O estudo teve como objetivo detectar a presença de anticorpos para língua azul em ovinos da região de Araçatuba, por ser esta uma região com rebanho expressivo e condições climáticas favoráveis à multiplicação de insetos. As amostras foram colhidas ao longo do ano de 2006, de ovinos adultos, em fase reprodutiva, (acima de 12 meses e com pelo menos uma parição, ou em caso de machos sexualmente maduros) e sem sintomas característicos da doença, de ambos os sexos, cadastrados no Núcleo de Produtores de Ovinos da Região de Araçatuba, distribuídas nos municípios da Região administrativa de Araçatuba. O tamanho da amostras foi calculado, considerando-se distribuição normal, prevalência de 50%, nível de confiança de 95% e precisão absoluta de 3%. Foram analisadas 1002 amostras de soros ovinos adultos, provenientes de 31 cabanhas, pelas provas de imunodifusão dupla em gel de agar (IDGA) e ELISA (Enzyme Linked immunosorbent Assay) de competição da fase sólida (ELISA CFS), provenientes do Centro Panamericano de Febre aftosa. Dessas amostras, 744 (74,3%) foram reagentes ao vírus da língua azul , pelo teste de ELISA-CFS e 651 (65,1%), pela técnica de IDGA. Não houve associação significante entre prevalência da doença e o sexo dos animais. Esses resultados revelam que o Vírus da Língua Azul encontra-se disseminado nessas regiões, sugerindo a ocorrência de infecções inaparente. / Abstract: Bluetongue (BT) is an infectious, non-contagious, insect-born viral disease of Ruminants. The causative agent of BT is bluetongue virus (BTV) that belongs to the family Reoviridae genus Orbivirus. Insect vectors in the genus Culicoides transmit this virus. BT affects domestic and wild ruminants, however small ruminants are considered the most affected specie. BT is included in the OIE list based on the differential diagnosis with Foot and Mouth Disease (FMDV), Vesicular Stomatitis Virus (VSV) and Sheep Pox Virus (SPV). The aim of the study was to detect antibodies against BTV in commercial sheep farms, of the Northeastern region of Sao Paulo State, Brazil. The size of the samples was calculated, considering normal distribution, prevalence of 50%, confidence level of 95% and absolute precision of 3%.A total of 1002 sera samples collected from adult sheep (above 1 year-old), comprising a total of 31 farms, were screened for the presence of BTV antibodies, by agar gel immunodiffusion test (AGID) and ELISA-CFS (Enzyme Linked Immunosorbent Assay - competitive solid phase), both produced by Pan American Center of FMDV. From a total of 744 samples 74,3% were positive by ELISA - CFS and 651 (65,1%) were positive by AGID. There was no significant association between prevalence of the disease and sex of animals.These results suggest that the BTV is widespread among farms, probably causing subclinical infections, with high level of antibodies. / Mestre
164

A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth

Claude, Bayingana January 2010 (has links)
Philosophiae Doctor - PhD / More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother’s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to PLBW. / South Africa
165

"A molecular investigation of the prevalence of suspected periodontopathogens and their association with preterm birth"

Bayingana, Claude January 2010 (has links)
Philosophiae Doctor - PhD / More than 20 million infants in the world (15.5 % of all births) are born with low birth weight. Ninety-five % of them are in developing countries. Oral colonization of Gramnegative anaerobes has been implicated as a risk factor for preterm delivery of low birth weight (PLBW) infants. The objective of this study was to investigate the association between periodontal pathogens and pre-term delivery of low birth weight (PLBW) infants. The study sample included 200 randomly selected women admitted to the department of obstetrics-gynecology of the teaching hospital of Butare in Rwanda. Mothers were asked to complete a questionnaire in order to identify factors which might pose a health risk to them and their infants. Gingival crevicular fluid (GCF) was collected from each quadrant of the mother’s month (using paper points) within 24 hours of delivery. Ten ml of foetal cord serum samples were collected at delivery and 10 ml of maternal serum samples were collected within 48 of delivery. GCF was examined by PCR for the presence of 5 periodontopathogens and ELISA was used for the evaluation of cytokines (IL-6 and IL-10) and immunoglobulins (IgM, IgG) in foetal cord and maternal blood against the periodontopathogens. P. intermedia showed significant associations either on its own or in combinations with most indicators of periodontal disease used in this study, while Aa and members of the red complex were significantly associated with gum bleeding and reduced frequency of tooth brushing. A strong association between PLBW and maternal and foetal cord serum sample levels of IL-10 was observed. Also, a good association was observed between PLBW and FCB sample levels of IL-6. Significant associations were observed between PLBW and maternal IgG against the different peridontopathogens. The findings of this study may suggest that the levels of maternal IgG and foetal IgM against the different periodontopathogens are associated with dissemination of maternal periodontopathogens to the foetus thereby illiciting an inflammatory response which contributes to PLBW.
166

Comparison between chemical and tissue culture methods to monitor environmental Estrogens

Baguma, Richard January 2012 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Endocrine disrupting compounds (EDCs) are exogenous compounds/chemicals in the environment that interfere with the synthesis, secretion, distribution and function or elimination of natural hormones in the body. Environmental estrogens are a subclass of EDCs that may mimic or inhibit the effect of endogenous estrogen and can therefore influence developmental and reproductive health in humans and animals. EDCs have been reported to adversely affect the reproductive, immune, endocrine and nervous systems of wildlife and humans. The effects of EDCs include gonadal abnormalities, altered male/female sex ratios, reduced fertility and cancers of the male and female reproductive tract to mention a few. These effects are difficult to detect. Although it is essential to screen for EDCs in aqueous environmental samples, most countries have failed to implement this as part of their routine water quality monitoring programs due to various constraints such as the high cost of assays and the lack of infrastructure and skills required to do the assays. Therefore, there is a clear need for more user-friendly, more economically viable and time saving assays that can be used for routine monitoring of environmental EDCs. The aim of this study was to investigate the comparison between chemical and tissue culture methods to monitor environmental estrogens. 28 environmental water samples were collected from various sites around South Africa and analyzed for EDCs using a battery of rapid in vitro tests. Samples collected for the current study were selected based on various human impacts and also to give approximately 50% high and 50% low estrogen values. The 28 environmental water samples were separated into two groups based on the estradiol ELISA. The estradiol ELISA was chosen because estradiol is the principal estrogen found in all mammalian species during their reproductive years. For this separation, an estradiol level of 5 pg/ml was used as cut-off. Of the 28 samples investigated, 15 had estradiol levels higher than 5 pg/ml and were designated as high estradiol. The remaining 13 samples contained estradiol at 5 pg/ml or less and they were designated as low estradiol The first objective of this study was to compare different rapid ELISAs for EDC monitoring to determine if the data obtained with these assays are similar/identical. The data obtained from the estrogenic ELISAs was related/similar and showed good correlation with each other. This is because the different estrogens are very similar and also due to the fact that the same sub-group in the population (the reproductively active females) is secreting these hormones. Therefore, an estradiol rapid assay was proposed as a first screening system for estrogens in samples. Even though there was a positive correlation between the estradiol rapid assay and testosterone rapid assay, separation of samples based on estradiol levels wasn’t a good predictor of testosterone levels in the samples. A testosterone rapid assay was therefore recommended as necessary to screen for androgens in samples. The positive correlation between the estradiol rapid assay and progesterone rapid assay was expected because both estradiol and progesterone are secreted and excreted by the same population sub-group (reproductively active females). This study also demonstrated a good predictability of separating samples containing progesterone using the estradiol ELISA. Progesterone is secreted by pregnant women, a sub-group of the reproductively active females. It is advised that a progesterone rapid assay be included to screen samples for progestogens The second objective of this study was to compare estradiol rapid ELISAs with a bioassay for anti-androgenicity using mouse testicular cell cultures. The mouse testicular cell testosterone synthesis bioassay to monitor anti-androgenicity of the samples showed no correlation between the ELISA data for estrogens. This study shows that anti-androgenic effects need to be monitored independently because the data for estrogenic compounds cannot be used as a predictor for anti-androgenic effects. This demonstrated the need for the inclusion of a mouse testicular cell testosterone synthesis bioassay to screen for androgenicity and anti-androgenicity of water samples. In summary, due to the different mechanisms of action of EDCs, this study recommended a battery of assays to monitor for EDCs. The battery of assays suggested is: v progesterone rapid assay was expected because both estradiol and progesterone are secreted and excreted by the same population sub-group (reproductively active females). This study also demonstrated a good predictability of separating samples containing progesterone using the estradiol ELISA. Progesterone is secreted by pregnant women, a sub-group of the reproductively active females. It is advised that a progesterone rapid assay be included to screen samples for progestogens. The second objective of this study was to compare estradiol rapid ELISAs with a bioassay for anti-androgenicity using mouse testicular cell cultures. The mouse testicular cell testosterone synthesis bioassay to monitor anti-androgenicity of the samples showed no correlation between the ELISA data for estrogens. This study shows that anti-androgenic effects need to be monitored independently because the data for estrogenic compounds cannot be used as a predictor for anti-androgenic effects. This demonstrated the need for the inclusion of a mouse testicular cell testosterone synthesis bioassay to screen for androgenicity and anti-androgenicity of water samples. In summary, due to the different mechanisms of action of EDCs, this study recommended a battery of assays to monitor for EDCs. The battery of assays suggested is: Estradiol ELISA as a rapid assay to screen for estrogens. Testosterone ELISA as a rapid assay to screen for androgens. Progesterone ELISA as a rapid assay to screen for progestogens. Mouse testicular cell testosterone synthesis bioassay to screen for androgenicity and anti-androgenicity.
167

Serology for Caseous lymphadenitis in sheep and goats – validation of an indirect ELISA and estimation of the seroprevalence in Sweden / Serologi för böldsjuka hos får och get - validering av en indirekt ELISA och uppskattning av seroprevalensen i Sverige

Widerlund, Liza January 2024 (has links)
Caseous lymphadenitis (CLA) is a disease primarily in sheep and goats, caused by Corynebacterium pseudotuberculosis, characterized by abscess formation in external and/or internal lymph nodes and organs. Economic losses occur due to emaciation, reduced milk production and impaired growth in affected animals. At the Swedish Veterinary Agency, bacterial culture is used as a diagnostic method for detecting CLA, requiring puncture of clinical abscesses. This sampling method increases the risk for disease transmission and overlooks animals affected by internal abscesses. In this study, a commercially available enzyme-linked immunosorbent assay (ELISA)-kit, based on an indirect ELISA, was validated for detecting antibodies for CLA, aiming for a more cost-effective and safer method that also can detect animals with internal abscesses. Serum and milk samples were analyzed to investigate the concordance between the two sample types. A subset of serum and milk samples was sent to Norway for analysis to compare the ELISA results, and comparison with another laboratory's results was conducted. The ELISA-kit demonstrated high sensitivity (92% for serum, 100% for milk), crucial for controlling CLA at herd level, while the specificity was estimated at 68% for serum and 61% for milk. To avoid increased and unnecessary culling of animals, a confirmatory method should analyze positive individuals to increase the specificity. Pooled milk samples could reduce costs for herd-level analysis, followed by serum sampling for positive herds.
168

Toxocaríase murina experimental: diagnóstico por PCR e comparação com técnicas imunológicas / Experimental murine toxocariasis: PCR diagnosis and its comparison with immunological techniques

Fonseca, Gabriela Rodrigues e 03 July 2018 (has links)
A toxocaríase é considerada uma das cinco parasitoses negligenciadas pelo Centers for Disease Control and Prevention e recebe ainda pouca atenção. As metodologias diagnósticas conhecidas são bem estabelecidas, apresentando, porém, limitações caracterizadas, sobretudo, pela ocorrência de reações-cruzadas. A biologia molecular mostra grandes avanços para o diagnóstico eficaz de diversas parasitoses, mas ainda carece de estudos em amostras de fácil obtenção para o diagnóstico da toxocaríase. Para aprimorar o conhecimento sobre a importância da técnica da Reação em Cadeia da Polimerase Convencional (PCR) e sua relação com técnicas diagnósticas já conhecidas, foram utilizados 42 camundongos BALB/c, machos, entre 6 a 8 semanas de vida, divididos em três grupos, inoculados com 5, 50 ou 500 ovos larvados e sangrados pelo plexo orbital aos 15, 30, 60 e 90 dias pós infecção. Ainda, do total, 24 camundongos foram sangrados aos 120 dias pós infecção. Ao final do experimento, foi realizada a recuperação de larvas e a PCR de tecido hepático, cérebro e carcaça de camundongos dos grupos infectados. As amostras de soro foram processadas pelas técnicas de ELISA, Western-blotting e PCR. O ELISA e o Western-blotting mostraram resultados reagentes em todas as datas para a maioria dos inóculos de ovos, com relação diretamente proporcional entre a detecção de anticorpos e a carga parasitária. Durante o período da infecção, a detecção de IgG foi mais intensa próxima aos 60 dias pós-infecção para a maioria dos inóculos de ovos, por ambos os métodos imunológicos. Apesar de identificar DNA de larvas e vermes adultos, a PCR não foi capaz de detectar DNA do parasito em amostras de soro em todos os grupos e datas pós-infecção. Em contrapartida, foi detectado DNA do parasito em todos os órgãos com ao menos um dos primers utilizados. Foram recuperadas larvas na maioria dos órgãos com maior porcentagem de recuperação relatada nos animais inoculados com 50 ovos larvados. O diagnóstico molecular, utilizando sangue do paciente, ainda não pode ser considerado uma ferramenta para o diagnóstico dessa infecção / Toxocariasis is considered by the Centers for Disease Control and Prevention one of the five neglected diseases and still receives little attention. The diagnostic methods are well established, presenting, however, limitations characterized mainly by the occurrence of cross-reactions. Molecular biology shows great advance for the effective diagnosis of several parasitic infections, but still lacks studies using samples that are easily obtained for the diagnosis of toxocariasis. In order to refine the knowledge about the importance of Conventional Polymerase Chain Reaction (PCR) and its relation with known techniques, 42 BALB/c male mice, between 6-8 weeks of age were inoculated with 5, 50 and 500 embryonated eggs respectively and bled by the orbital plexus at 15, 30, 60 and 90 days post infection. Also, 24 of 42 animals were bled the same way at 120 days post-infection. At the end of the experiment, larval recovery and conventional PCR were performed in liver, brain and carcass of mice of the infected groups. Serum samples were processed by ELISA, Western-blotting and PCR. The ELISA and Western-blotting techniques showed positive results in all days post infection for most eggs inocula and showed a directly proportional dependence between the infective dose and the level of antibodies. During the course of the infection, IgG detection was most intense near 60 days post infection for most eggs inocula, for both diagnostic methods. Despite positive DNA identification in larvae and adult worms, PCR wasn\'t able to detect parasite DNA in serum samples in all infected groups and days post infection. In contrast, parasite DNA was detected in all organs with at least one of the primers. Larvae were recovered from most organs, and animals inoculated with 50 embryonated eggs showed the highest percentage of larval recovery. Molecular diagnosis using patient\'s blood is not the best tool for toxocariasis diagnosis so far
169

Imunodiagnóstico da estrongiloidíase humana frente a diferentes frações antigênicas de Strongyloides venezuelensis / Immunodiagnosis of human strongyloidiasis by different antigenic fractions of Strongyloides venezuelensis

Corral, Marcelo Andreetta 21 May 2014 (has links)
A estrongiloidíase é a infecção parasitária causada pelo nematódeo Strongyloides stercoralis. O diagnóstico definitivo é realizado pela visualização de larvas, principalmente nas fezes. Porém as técnicas parasitológicas têm baixa sensibilidade. As técnicas sorológicas apresentam-se como importante alternativa diagnóstica. Pesquisas apontam para a utilização de antígenos heterólogos solúveis, principalmente de Strongyloides venezuelensis. A identificação e caracterização dos antígenos de membrana podem fornecer fonte alternativa de antígenos e assim auxiliar o desenvolvimento das técnicas imunológicas. O presente trabalho teve como objetivo a avaliação das técnicas ELISA e WB frente a diferentes frações antigênicas de larvas filarioides de S. venezuelensis. Foram utilizadas amostras de sangue e fezes de 92 indivíduos, 20 indivíduos com estrongiloidíase (grupo I), 32 indivíduos com outras parasitoses (grupo II) e 40 indivíduos negativos (grupo III) pelos métodos de Lutz, cultura em placa de ágar e Rugai. Para preparação dos antígenos foram utilizadas larvas infectantes obtidas a partir de ratos infectados experimentalmente com S. venezuelensis. Seis frações antigênicas foram preparadas: frações salinas solúveis e de membrana (PBS 0,01M pH 7,2 e SDS 1%, SS e MS; Tris-HCl 25mM pH 7,5 e CHAPS 1%, ST e MT, respectivamente) e frações alcalinas solúvel e de membrana (NaOH 0,15M e SDS 1%, SA e MA, respectivamente). Para a técnica ELISA foram utilizadas placas sensibilizadas com 10ug/mL de antígeno, soro dos indivíduos diluídos 1:200 em PBS 0,05% Tween 3% de leite (PBSTM) e o conjugado (anti IgG-humana peroxidase) em PBSTM. As amostras foram consideradas positivas quando o Índice ELISA foi maior que 1. Para a técnica de WB os soros foram diluídos 1:100 em Tris-HCl 5% de leite (TM) e o conjugado (anti IgG-humana peroxidase) em TM. Após as técnicas sorológicas foram determinadas os parâmetros de diagnóstico pela curva ROC como sensibilidade (SE), especificidade (ES), Likelihood ratio (LR) além da determinação da acurácia diagnóstica (AC) e do índice Kappa (k). A técnica ELISA destacou as frações de membrana com melhor desempenho em relação aos parêmetros diagnósticos estudados (SE 95%, ES 94,4%, AC 94,8%, LR 17,1, k 0,848). O WB revelou componentes antigênicos imunodominantes variando de 260-10kDa, mas destacam-se as frações de 40-35kDa mais frequentes em todas frações antigênicas. Pela técnica de WB, a fração ST apresentou melhor desempenho em relação aos parêmetros diagnósticos estudados (SE 100%, ES 93,1%, AC 94,5, LR 14,4,k 0,854). A utilização das frações de membrana no imunodiagnóstico da estrongiloidíase humana torna-se fonte acessível e eficaz em relação às frações purificadas, não necessitando de gastos complementares para sua obtenção / Strongyloidiasis is a parasitic infection caused by a nematode Strongyloides stercoralis. The definitive diagnosis is made by the larvae visualization in stool samples. However parasitological techniques have low sensitivity. Serological techniques became as suitable diagnostic alternative. Research indicates for the soluble heterologous antigen utilization, mainly Strongyloides venezuelensis. Identification and characterization of membrane antigen may constitute an alternative source of antigen and then assist the development of serological techniques. The aim of this study was evaluate ELISA and WB techniques behind different antigenic fractions of S. venezuelensis´ infective larvae. A total of 92 serum and stool samples was analyzed, 20 from individuals with strongyloidisis (group 1), 32 with other parasitic diseases (group 2) and 40 from individuals with negative coproparasitology (group 3) using Lutz, agar plate culture and Rugai methods. For the antigen preparation infective larvae of S. venezuelensis from experimental infected rats were employed. Six antigenic fractions were prepareted: saline soluble and from membrane fractions (0.01M PBS pH 7.2, and 1% SDS, SS and MS; 25mM Tris-HCl pH 7.5, 1% CHAPS, MT and ST, respectively) and alkaline soluble and membrane fractions (0.15 M NaOH and 1% SDS, SA and MA, respectively). For ELISA technique, plates were sensitized with 10 ug/mL of antigen, serum samples were diluted 1:200 in 0.05% Tween in PBS 3% milk (PBSTM) and conjugate (anti-human IgG peroxidase) in PBSTM. Positive samples were considered when ELISA index was greater than 1. To WB technique, serum samples were diluted 1:100 in Tris-HCl 5% milk (TM) and conjugate (anti-human IgG peroxidase) in the TM. After serological techniques diagnostics parameters were determined by ROC curve how sensitivity (SE), specificity (ES), Likelihood ratio (LR) and determination of diagnostic accuracy (AC) and Kappa (k) index. ELISA technique highlighted the membrane fractions with better performance compared to parameters diagnoses studied (95% SE, 94.4% ES, 94.8% AC, 17.1 LR, 0.848 k). The WB revealed immunodominant antigenic components ranging from 260-10kDa, but there are the fractions of 40-35kDa more frequent in all antigenic fractions. WB technique showed ST fraction better performance in relation to the diagnostic parameters (100% SE, 93.1% ES, 94.5% AC, 14.4 LR, 0.854 k). Membrane fractions in the immunodiagnosis of human strongyloidiasis become an accessible and effective source of antigens in relation to the purified fractions, requiring no additional expense to obtain it
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Ocorrência de Cryptosporidium spp. em crianças e seus respectivos cães e gatos de estimação no município de Andradina, SP /

Coelho, Natalia Marinho Dourado. January 2009 (has links)
Orientador: Katia Denise Saraiva Bresciani / Banca: Carlos Noriyuki Kaneto / Banca: Alessandro Francisco Talamini do Amarante / Resumo: O objetivo deste estudo foi avaliar a ocorrência de Cryptosporidium spp. em crianças e seus respectivos cães e gatos de estimação residentes no Município de Andradina, SP, por meio do Teste de Imunoadsorção Enzimática (ELISA). Durante o período de janeiro a agosto de 2009, foram analisadas 188 amostras fecais de crianças, bem como de seus respectivos cães e gatos de estimação para pesquisa de Cryptosporidium spp. O teste quiquadrado (χ2) foi utilizado para verificar a associação entre as variáveis: sexo, idade, raça e consistência fecal, com nível de significância de 5%. Pelo ELISA foi detectado Cryptosporidium spp. em em amostras fecais de 2,1% (4/188) das crianças com idade inferior a sete anos. Entre os animais examinados, 6,8% (9/132) dos cães e 5,4% (3/56) felinos apresentaram amostras positivas para este coccídeo. Tanto nas crianças como nos animais não houve influencia do sexo e da idade na detecção do Cryptosporidium spp. sendo que nestes últimos a raça também não influenciou (P> 0,05). Neste trabalho foi evidenciada uma baixa ocorrência deste parasito nas crianças, assim só será possível determinar com precisão a relação entre a infecção das crianças com dos animais, com a posterior caracterização molecular deste protozoário. / Abstract: The objective this study was to evaluate the occurrence of Cryptosporidium spp. in children and their dogs and pet cats in the city of Andradina, SP. through Test-linked immunosorbent assay (ELISA), during the period from January to August 2009, we analyzed 188 fecal samples from children, as well as their dogs and pet cats for detection of Cryptosporidium spp. The chi-square test (χ2) was used to verify the association between gender, age, race and fecal consistency, with a significance level of 5%. Using ELISA was detected Cryptosporidium spp. in stool samples in 2.1% (4/188) of children under the age of seven years. Among the animals examined, 6.8% (9/132) of dogs and 5.4% (3/56) cats had positive samples for this coccidium. Both children and animals there was no influence of sex and age on the detection of Cryptosporidium spp. being that in these last race did not influence (P> 0.05). This study demonstrated a low occurrence of this parasite in children, so only you can accurately determine the relationship between the infection of children with the animal with the molecular characterization of this parasite. / Mestre

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