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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

The induction of protective immunity to Schistosoma mansoni in mice : in vivo lymphocyte responses in the draining lymph nodes

Constant, Stephanie Louise January 1991 (has links)
No description available.
2

Molecular studies of Venezuelan sandflies and Leishmania isolates

Adamson, Rachel Elizabeth January 1994 (has links)
No description available.
3

The epidemiology of Trypanosoma vivax and its effects on cattle productivity in the northern tropical zone of Colombia

Otte, Joachim January 1989 (has links)
No description available.
4

Studies of skin and lung phase challenge attrition in the irradiated vaccine model of schistosomiasis mansoni

Ward, R. E. M. January 1988 (has links)
No description available.
5

Methods of inference for high variance within-host models of lymphatic filariasis

Riley, S. January 2002 (has links)
No description available.
6

Epidemiology of the Leishmaniases in southwest Saudi Arabia

Al-Zahrani, Mohammed Ali January 1988 (has links)
Visceral (VL) and cutaneous leishmaniasis (CL) are public health problems in the southwest of Saudi Arabia. The causative parasites, the vectors and the possible animal reservoirs In that area were all unknown before this study began. Because of the size of the area and to achieve the different aims of the study, a laboratory was established in Abha City which is in the centre of the study area, altitude approximately 2000 m. More than 50 isolates from CL lesions, 17 from VL patients and 700 human filter paper blood samples were collected. Eighty nine feral dogs were captured In Kala-azar endemic areas and examined for Leishmania. More than 8,000 sandflies collected from fixed stations were examined and more than 1600 Phlebotomus females were dissected. Forty four human isolates from human CL lesions were typed by the isoenzyme technique which showed that L. tropica is responsible for CL in both lowlands (altitude about 450 - 700 m) and the highlands (altitude about 2000 m). Only one zymodeme (LON-63) was found in the isolates from the lowlands but, in the highlands, four zymodemes (LON-10, 71, 72 and 73) were found. Zymodemes LON-10 and LON-71 were also Isolated from Phlebotomus sergenti, which has been shown clearly to be a major vector of L. tropica In the highlands. Animal susceptibility experiments showed. that neither BALB/c mice nor the golden hamster were susceptible to L. tropica. L. donovani sensu lato zymodeme LON-42 causes zoonotic Infantile Kala-azar in areas at altitudes of up to 700m. Neither the vector nor the reservoir host were identified in spite of an active search for them. The limited sero-epidemiological survey using the ELISA procedure revealed a high frequency of antibodies in children in Al Baha province, much greater than was previously believed to exist. Feral dogs In this area were found to be carriers of typical L. infantum, NOT the parasite found in man. The prevalence rate in dogs was high (19.3%). The dog's possible role in the epidemiology of Kala-azar in the study area is discussed. The entomological studies revealed that six species of Phlebotomus exist in the study area, with Ph. sergenti as the dominant species In the highlands and Ph. bergeroti in the lowlands. Some species such as Ph. arabicus are limited to high altitudes (about 2000 m), and others such as Ph. alexandri to low altitudes (up to 700 m). Ph. orientalis was found mainly in the highlands but a few samples were collected from the lowlands. Sergentomyi species were abundant in all areas. The seasonal distribution based on a longitudinal study indicated that the population peak in both ecological areas (high and lowlands) occurs in July. The factors Including the collection method and trap sites controlling the apparent seasonal distributions are discussed. Statistical data on the total cases of CL and VL reported In The Kingdom are presented and data from the study area are compared with those from other areas such as the Eastern Province (where L. major is dominant) to give an overall picture of the leishmaniases throughout the country.
7

Antiplasmodial- and chloroquine resistance reversal properties of a new diterpene from Croton steenkampianus

Prozesky, Erwin Antoni 13 August 2008 (has links)
Malaria remains the most serious and deadly parasitic disease, affecting millions of people mostly in the poorest countries in the world. With no vaccine likely in the foreseeable future, drugs remain the best means of controlling the disease. Plants have provided most of the antimalarial drugs so far and it is likely that more antimalarial drugs will be discovered in this way. A previous study on South African plants yielded very good results on the extract level. In this study Croton steenkampianus leaf extract was selected for isolation of active principles. Bio-guided fractionation of the extract was done on silica column chromatography and Sephadex column chromatography. Five compounds, two favonoids, a triterpene and two new diterpenes, with a novel skeleton were isolated. Compounds were identified with NMR, MS and X-ray crystallography. Antiplasmodial activity of the compounds varied from moderate to excellent, with crotrene A having excellent activity. Further studies on the antimalarial potential of this compound are planned. Cytotoxicity of compounds and extract were determined against human lymphocytes. Results obtained had an ID50 between >16,61 µg/ml. The therapeutic indexes were between 2.75 and 55.18, showing poor to moderate selectivity towards Plasmodium. Crotrene A had the best therapeutic index and more detailed studies on its cytotoxicity are necessary. Resistance to antimalarial drugs is a major problem in effective treatment of the disease. One way of overcoming this problem is combination drugs working synergistically. Chloroquine the most affordable antimalarial drug was combined with the isolated compounds. Two compounds showed synergistic activity with crotrene A having excellent activity, completely reversing chloroquine resistance. This combination of drugs showed no synergistic cytotoxic effects and its potential as a drug will be further investigated. The mode of action of antimalarial drugs can provide useful information about the long term potential and the likelihood of resistance development. Crotrene A was subjected to a basic test to determine a possible mode of action. Results showed a marked effect in the early phase of development (rings). The results suggest a very potent mode of action able to reduce the amount of parasites quickly and this holds promise for further development of this compound. / Thesis (DPhil)--University of Pretoria, 2008. / Plant Science / unrestricted
8

Presença de Leishmania sp em equinos de zona urbana de Uruguaiana, Rio Grande do Sul

Escobar, Taiane Acunha 16 April 2015 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-12T14:39:20Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIANE ACUNHA ESCOBAR.pdf: 973361 bytes, checksum: 098a27b7377e80f12957e7c2e3378ef3 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-12T14:39:36Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIANE ACUNHA ESCOBAR.pdf: 973361 bytes, checksum: 098a27b7377e80f12957e7c2e3378ef3 (MD5) / Made available in DSpace on 2016-09-12T14:39:36Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TAIANE ACUNHA ESCOBAR.pdf: 973361 bytes, checksum: 098a27b7377e80f12957e7c2e3378ef3 (MD5) Previous issue date: 2015-04-16 / A Leishmaniose é uma doença parasitária infeciosa, causada por protozoários do gênero Leishmania e transmitida pelo vetor flebótomo. Caracterizada como Doença Tropical Negligenciada, acomete diversas espécies de mamíferos, sendo o cão, atualmente, o principal reservatório em área urbanas. Os equinos também podem ser infectados, especialmente quando estão em contato com reservatórios ou vetores. No município de Uruguaiana – RS há um expressivo número de equinos utilizados na tração de cargas e como meio de transporte, com constante movimentação dentro do perímetro urbano. Esses animais vivem em condições precárias, submetidos a trabalhos excessivos e má nutrição. Frente a estes fatores somados à atual situação epidemiológica da leishmaniose visceral canina no município, o presente estudo foi realizado com o objetivo de identificar a presença de Leishmania sp em equinos urbanos do município de Uruguaiana-RS. Para a condução do experimento foram utilizadas amostras sanguíneas de 192 equinos testadas em três técnicas: sorológica (ELISA), imunocromatográfica (TR-DPP) e molecular (PCR). Na técnica de ELISA foi utilizado soro, testado com o Kit Ensaio Imunoenzimático para Diagnóstico da Leishmaniose Visceral Canina – Bio-Manguinhos e para o teste imunocromatográfico Teste Rápido Dual Path Platform utilizaram-se amostras de sangue total. As reações de PCR, após extração de DNA de sangue periférico dos animais, foram realizadas com quatro pares de iniciadores distintos. Todas as amostras testadas apresentaram-se não reagentes nos ensaios imunológicos. Entretanto, com o emprego da técnica PCR, mais sensível, houveram amostras positivas. Dos quatro pares de iniciadores testados, 75 amostras foram positivas, 52 com pelo menos um dos pares. Contudo, ao analisarmos individualmente os iniciadores, 58,6% foram positivos para LITSV/L5.8SR, 44% para LITSV/LISTSR, 28% para RV1/RV2, e 4% LITSR/L5.8S. Os resultados apresentados no experimento indicam a possibilidade de existência de Leishmania em equinos na região de Uruguaiana, embora os testes sorológicos não tenham apresentado reatividade para Leishmania. A técnica molecular possibilitou a detecção do gênero Leishmania nas amostras de sangue periférico dos equinos. Este foi o primeiro relato da infecção na espécie equina na região do extremo oeste do estado do Rio Grande do Sul. Contudo, se faz importante a realização de sequenciamento do fragmento para que se possa confirmar a identidade genética de Leishmania sp. / Leishmaniasis is an parasitic infectious disease caused by protozoa genus Leishmania and transmitted by the sandfly vector. Characterized as Neglected Tropical Disease, affects several species of mammals, and the dog are main reservoir in urban areas. The horses can also be infected especially when they are in contact with reservoirs or vectors. In Uruguaiana’s city, there is a significant number of horses used in the tensile loads and means of transport, with constant movement within the city, living in precarious work’s conditions, subjected to excessive and poor nutrition. In view of these factors added to the current epidemiological situation of LVC in the city, the present study aim to identify the presence of Leishmania in urban horses the municipality of Uruguaiana-RS. For the experiment, blood samples from 192 horses were used for holding three techniques: serological (ELISA), immunochromatographic (TR-DPP) and molecular (PCR). For conducting ELISA’s Test serum was used and tested with Bio-Manguinhos kit and for TR-Dual Path Platform Rapid Test whole blood samples were employed. In the PCR technique, DNA was extracted from peripheral blood of animals and amplifications were performed with primers RV1 / RV2, LITSR / LITSV, LITSR / L5.8S / LITSV / L5.8SR.. All tested samples showed negative results in immunoassays. However, employing sensitive techniques such as PCR, positive samples were detected. Considering the four primer pairs tested, 75 animals were positive, 52 with at least one of the pairs. However, when analyzing the individual primers, 58.6% were positive for LITSV/L5.8SR, 44% to LITSV/LISTSR, 28% for RV1/RV2, and 4% LITSR/L5.8S.In The results presented in the experiment indicate the possibility of Leishmania in horses in the region of Uruguaiana city, although serological tests have not submitted reactivity to Leishmania. Molecular technich shows results to consider the Leishmania’s presence in horse’s peripheral blood samples. This was the first report of infection in equine species in westernmost region of the Rio Grande do Sul state. However, it is important to conduct sequencing of the fragment so that we can confirm the genetic identity of Leishmania sp.
9

Aspectos epidemiológicos das infecções por Toxoplasma gondii, Neospora caninum e Chlamydophila abortus em caprinos no estado de Alagoas

ARDERLINI, Giulliano Aires 10 February 2009 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-10-10T15:19:58Z No. of bitstreams: 1 Giulliano Aires Anderlini.pdf: 1405471 bytes, checksum: 7d4130063d4be965f6896a3b0207d35f (MD5) / Made available in DSpace on 2016-10-10T15:19:58Z (GMT). No. of bitstreams: 1 Giulliano Aires Anderlini.pdf: 1405471 bytes, checksum: 7d4130063d4be965f6896a3b0207d35f (MD5) Previous issue date: 2009-02-10 / The objective of this paper was to determine the prevalence and to identify the risks concernig to Toxoplasma gondii, Neospora caninum and Chlamidophyla abortus goats infections in the State of Alagoas. The research took place on 24 farms of goat breeding from 10 municipalities around the three different Alagoas Mesoregions. A total of 454 goat sera sample were examined for anti-Toxoplasma gondii and anti-Neospora caninum antibodies studies through out indirect immunofluorescence antibody test (IFIAT). To detect anti-Chlamidophyla abortus antibodies 255 goat serum were tested by micro method of complement fixation. The farms were analyzed by questionnaires considering their production system, nutritional, reproductive and sanitary management in order to evaluate the risks of toxoplasmosis in goats. The prevalence of anti-Toxoplasma gondii antibodies was 39% with 95,8% of farms presenting seropositive animals. Significant association was observed to mesoregion (OR = 0,23; I.C. 95% = 0,09 – 0,57), age (OR = 0,36; I.C. 95% = 0,20 – 0,64), semi-intensive herd management (OR = 8,70; I.C. 95% = 1,87 – 40,43), cats accessing to water offered to animals (OR = 3,38; I.C. 95% = 1,89 – 6,02) and cats eating placental remnants (OR = 2,73; I.C. 95% = 1,38 – 5,40). The prevalence of anti- Neospora caninum antibodies was 5,3% with 62,5% of farms presenting seropositive animals with no significant association observed to variables searched as risk factors in this study. Concerning to anti-Chlamidophyla abortus antibodies were observed general prevalence of 1,17%. We conclude that goat herd in the State of Alagoas is exposed to infections by T. gondii, N. caninum and C. abortus with events in different State Mesoregions. It is necessary to intensify and go deep on the epidemiological studies in addition to implementing orientation programs for farmers on sanitary care and goats management in order to reduce the prevalence of infection by those pathogens. / Objetivou-se com este estudo determinar a prevalência e identificar os fatores de risco associados às infecções por Toxoplasma gondii, Neospora caninum e Chlamydophila abortus em caprinos do Estado de Alagoas. A pesquisa foi realizada em 10 municípios, sendo analisadas 24 propriedades de produção de caprinos com aptidão mista situadas nas três Mesorregiões do Estado de Alagoas. Foram coletadas amostras sanguíneas de 454 animais para pesquisa de anticorpos anti-Toxoplasma gondii e anti- Neospora caninum através da prova sorológica de Imunofluorescência Indireta. Para pesquisa de anticorpos anti-Chlamydophila abortus foram utilizadas amostras sanguíneas de 255 matrizes caprinas sendo utilizada a microtécnica da Reação da Fixação do Complemento. Para o estudo dos fatores de risco foram aplicados questionários com questões referentes ao sistema de produção e manejos nutricional, reprodutivo e sanitário. A prevalência geral de anticorpos anti-Toxoplasma gondii foi de 39% com 95,8% das propriedades apresentando animais positivos. Foi observadaassociação significativa para as variáveis: Mesorregião (OR = 0,23; I.C. 95% = 0,09 –0,57), idade (OR = 0,36; I.C. 95% = 0,20 – 0,64), sistema de criação semi-intensivo(OR = 8,70; I.C. 95% = 1,87 – 40,43), acesso dos gatos à água fornecida aos animais (OR = 3,38; I.C. 95% = 1,89 – 6,02) e gatos se alimentando de restos placentários (OR = 2,73; I.C. 95% = 1,38 – 5,40). A prevalência geral de anticorpos anti-Neospora caninum foi de 5,3% com 62,5% das propriedades apresentando animais positivos não sendo observada associação significativa para os fatores analisados. Com relação a anticorpos anti- Clamydophila abortus observou-se prevalência geral de 1,17%. Conclui-se que o rebanho caprino do Estado de Alagoas está exposto às infecções por T. gondii, N. caninum e C. abortus com focos da infecção nas diferentes Mesorregiões do Estado. É necessário intensificar e aprofundar os estudos epidemiológicos além de implementar programas de orientação aos produtores sobre medidas sanitárias e de manejo dos rebanhos caprinos objetivando reduzir a prevalência de infecção por estes agentes patogênicos.
10

Espectro de ação antiparasitária do óleo da semente da Carapa guianensis, Aubl. em animais domésticos / Antiparasitic spectrum action of the seed oil of Carapa guianensis Aubl. in domestic animals

FARIAS, Márcia Paula Oliveira 21 February 2011 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-10-18T16:00:21Z No. of bitstreams: 1 Marcia Paula Oliveira Farias.pdf: 1623916 bytes, checksum: 1a0daf135aada1dcc8ca0fd3a7aa94c3 (MD5) / Made available in DSpace on 2016-10-18T16:00:21Z (GMT). No. of bitstreams: 1 Marcia Paula Oliveira Farias.pdf: 1623916 bytes, checksum: 1a0daf135aada1dcc8ca0fd3a7aa94c3 (MD5) Previous issue date: 2011-02-21 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The herbal drugs have been widely studied in order to obtain an effective and ecologically viable alternative for the control of parasitic diseases of domestic animals. It was evaluated the spectrum of antiparasitic action of the seed oil of Carapa guianensis against muscidae, ticks, lice and gastrointestinal nematodes of domestic animals. The action against muscidae was assessed against the first larval (L1) and third stage (L3) from Musca domestica and Stomoxys calcitrans adults. For ticks it was determined the IC50 (Inhibitory Concentration Medium) and LC50 (median lethal concentration) on Rhipicephalus (Boophilus) microplus, and Rhipicephalus sanguineus Anocentor nitens. Against lice it was determined the efficacy against Damalinia caprae. The in vivo efficacy in mice naturally infected with Syphacia obvelata and in goats and sheep naturally infected with gastrointestinal helminths was determined and also the effect of oral administration of seed oil of C. guianensis on hematological and biochemical parameters in goats and sheep. The results revealed that the seed oil of Carapa guianensis exerted negative effect on M. domestica bioactivity causing severe mortality and reduced larval and pupal weight of larvae, show repellency on Stomoxys calcitrans and have significant potential in the control of ticks of domestic animals, interfering with their reproduction revealing an IC50 of 4.332, 4.850, 4.903, and an LC50 of 5.228, 5.362 and 5.698, respectively, for females and larvae of R. (B.) microplus, A. nitens and Rhipicephalus sanguineus. The seed oil of Carapa guianensis has in vitro activity against adult Damalinia caprae and the anthelmintic tests using mice, goats and sheep revealed an ineffective anthelmintic activity in all treatments. The evaluation of hematological and biochemical parameters of goats and sheep in general did not determine difference in the values of the erythrocyte, total leukocyte and biochemical parameters. / Os fitoterápicos têm sido amplamente estudados visando-se obter uma alternativa eficaz e ecologicamente viável para o controle das doenças parasitárias dos animais domésticos. Avaliou-se o espectro de ação antiparasitária do óleo da semente de Carapa guianensis, Aubl. contra muscídeos, ixodídeos, fitirápteros e nematóides gastrintestinais de animais domésticos. A ação contra muscídeos foi avaliada contra larvas de primeiro (L1) e terceiro estádio (L3) de Musca domestica e adultos de Stomoxys calcitrans. Para os carrapatos determinou-se a CI50 (Concentração Inibitória Média) e CL50 (Concentração Letal Média) sobre Rhipicephalus (Boophilus) microplus, Anocentor nitens e Rhipicephalus sanguineus. Contra os fitirápteros determinou-se a eficácia contra Damalinia caprae. Com relação aos helmintos gastrintestinais determinou-se in vivo a eficácia em infectados com o oxiurídeo Syphacia obvelata e contra nematóides gastrintestinais de caprinos e ovinos naturalmente infectados. Foi avaliado ainda o efeito da administração oral do óleo da semente da C. guianensis sobre os parâmetros hematológicos e bioquímicos em caprinos e ovinos. Os resultados revelaram que o óleo da semente da Carapa guianensis exerce bioatividade negativa sobre M. domestica, provocando acentuada mortalidade larval e pupal e redução no peso das pupas; apresenta atividade de repelência sobre Stomoxys calcitrans; possui significativo potencial no controle dos ixodídeos dos animais domésticos, interferindo na sua reprodução revelando uma CI50 de 4,332; 4,850; 4,903, e uma CL50 de 5,228; 5,362 e 5,698, respectivamente, para fêmeas e larvas de R. (B.) microplus, A. nitens e Rhipicephalus sanguineus; apresenta atividade piolhicida in vitro contra Damalinia caprae adultos. Os testes antihelmínticos utilizando como modelo experimental camundongos revelaram atividade antihelmíntica não efetiva em todos os tratamentos utilizados com eficácia variando de 30,36% a 54,72%; quando administrado por via oral em caprinos e ovinos naturalmente infectados por nematóides gastrintestinais não se apresentou efetivo na redução da eliminação de ovos e na inibição do desenvolvimento de larvas de nematóides gastrintestinais. A avaliação dos parâmetros hematológicos e bioquímicos dos caprinos e ovinos de um modo geral não determinou diferença significativa nos valores do eritrograma, leucócitos totais e parâmetros bioquímicos.

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