Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 170-204). Also available in print.

Tuberculosis has re-emerged as a global health problem due to co-infection with HIV and the emergence of drug resistant strains of Mycobacterium tuberculosis. There is a need for a reliable and fast serodiagnostic assay to reduce the time required for test results from weeks to hours, in order to better control the spread of the disease. Previous studies have shown that TB patients contain antibodies against M. tuberculosis mycolic acids. In standard immunoassays such as ELISA, an unacceptable number of false positive and negative test results were obtained. This study aimed at assessing the potential of detecting anti-mycolic acids antibodies in TB patient sera on a biosensor as surrogate marker for TB infection. Mycolic acid liposomes were immobilized reproducibly on a non-derivatized biosensor cuvette and blocked with saponin. A high dilution of serum in PBS/ AE was used to calibrate the signal of the two cells, followed by binding of patient sera inhibited with either mycolic acid, cholesterol or placebo phosphatidylcholine liposomes at a lesser dilution. The inhibition was done to confirm the specificity of the binding response. There was no inhibition of binding when a sputum negative control serum (HIV-TB-) was pre-incubated with either cholesterol or mycolic acids on the biosensor coated with mycolic acid liposomes. The antibodies that are specific to mycolic acid were demonstrated in all TB positive patients on mycolic acids coated cuvette cell surfaces after pre-incubation of serum with mycolic acids. The patient sera that were false positive and false negative on ELISA tested negative and positive respectively on the biosensor. Only sera from two patients, both HIV positive, tested false positive on both ELISA and biosensor. The biosensor was able to detect anti-mycolic acids antibodies of even low affinity. In ELISA, these antibodies were washed away. No inhibition of antibody binding on cholesterol-coated cuvettes was found after pre-incubation of serum with mycolic acids or cholesterol liposomes. The cholesterol surface became unstable during pre-incubation of serum with mycolic acids. Mycolic acid appeared to be a stronger antigen than cholesterol. The anti-mycolic acids antibodies were specific and sensitive for diagnosis of TB on the biosensor. More sera should be analyzed on the biosensor to make a statistically accountable statement on whether the improved sensitivity and specificity is adequate for a simple, rapid, sensitive and accurate biosensor-based serodiagnostic assay. / Dissertation (MSc(Biochemistry))--University of Pretoria, 2006. / Biochemistry / unrestricted

Ball State University LibrariesLibrary services and resources for knowledge buildingMasters ThesesThere is no abstract available for this thesis.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

Thesis (Ph. D.)--University of Missouri--Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 97-104). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 1999. / "May 1999." Typescript. Vita. Includes bibliographical references (leaves 97-104). Also available on the Internet.

Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [72]-90).

Made available in DSpace on 2014-06-11T19:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-15Bitstream added on 2014-06-13T20:56:04Z : No. of bitstreams: 1 meirelles_rb_me_jabo.pdf: 431142 bytes, checksum: 402455070a5e87681746e4ec463e7683 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O trabalho teve por objetivo avaliar a prova do antígeno acidificado tamponado após tratamento dos soros com rivanol (AAT-RIV), como teste confirmatório no diagnóstico sorológico da brucelose bovina. Foram selecionadas 1.061 amostras de soros bovinos, previamente analisadas pelos testes preconizados pelo Programa Nacional de Controle e Erradicação de Brucelose Tuberculose (PNCEBT): como teste de triagem, a prova do antígeno acidificado tamponado (AAT), e como testes confirmatórios, a combinação das provas de soroaglutinação lenta e 2-mercaptoetanol (SAL+2-Me), e a reação de fixação de complemento (RFC). O AAT-RIV foi realizado com o antígeno nas concentrações de 8% e 4% de volume celular, não tendo sido encontrada diferença nos resultados. Os dados foram analisados pelo indicador kappa e pelo χ2 de McNemar, adotando-se com ponto-de-corte o título 25 no 2-Me e 4 na RFC. O AAT-RIV apresentou concordância regular (kappa = 0,53) com o AAT e boa com os testes confirmatórios (kappa: 2-Me = 0,67; SAL+2-Me = 0,66; RFC = 0,76). O χ2 de McNemar apontou diferenças significativas entre os testes. A comparação entre os resultados do AAT-RIV e a condição verdadeira do animal, estabelecida pela combinação dos resultados das provas AAT, SAL+2-Me e RFC, resultou em uma sensibilidade relativa de 76,5%, com intervalo de confiança (95%) de 72,7% a 80,3%, e especificidade relativa de 100%. Conclui-se que o AAT-RIV poderia ser utilizado como teste confirmatório no diagnóstico sorológico da brucelose bovina, sendo os animais com resultado positivo considerados infectados e aqueles com resultado negativo submetidos a um dos dois testes confirmatórios adotados pelo PNCEBT. / The purpose of the investigation was to evaluate the rose Bengal plate test in bovine serum after treatment with rivanol (RBPT-RIV) as a confirmatory test for brucellosis diagnosis. Serum samples from 1,061 bovine were analyzed by serological diagnostic techniques adopted by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication: as screening test, the rose Bengal plate test (RBPT), and as confirmatory tests, the 2- mercaptoethanol plus standard tube agglutination test (STAT+2-Me), and the complement fixation test (CFT). RBPT-RIV was performed with 8% and 4% cellular concentration antigen, and there was no difference between the results. Data were analyzed by kappa statistic and McNemar χ2 (2-Me cut-off = titer 25, and CFT cutoff = titer 4). RBPT-RIV showed a moderate agreement (kappa = 0,53) with RBPT, and substantial agreement with the confirmatory tests (kappa: 2-Me = 0,67; STAT+2-Me = 0,66; CFT = 0,76). The McNemar χ2 showed significant difference among the tests. Comparing the RBPT-RIV results with the true condition of the animals, stablished by combining the results of RBPT, STAT+2-Me and CFT, the relative sensitivity was 76.5%, with a 95% confidence interval from 72,7% to 80.3%, and relative specificity of 100%. The results suggested that the RPBT-RIV is suitable to be used as a confirmatory test for brucellosis serological diagnosis; in this case, an animal testing positive should be classified as infected, and an animal testing negative should be tested by CFT or STAT+2-Me.

Orientador: Luís Antonio Mathias / Banca: Samir Issa Samara / Banca: Jane Megid / Resumo: O trabalho teve por objetivo avaliar a prova do antígeno acidificado tamponado após tratamento dos soros com rivanol (AAT-RIV), como teste confirmatório no diagnóstico sorológico da brucelose bovina. Foram selecionadas 1.061 amostras de soros bovinos, previamente analisadas pelos testes preconizados pelo Programa Nacional de Controle e Erradicação de Brucelose Tuberculose (PNCEBT): como teste de triagem, a prova do antígeno acidificado tamponado (AAT), e como testes confirmatórios, a combinação das provas de soroaglutinação lenta e 2-mercaptoetanol (SAL+2-Me), e a reação de fixação de complemento (RFC). O AAT-RIV foi realizado com o antígeno nas concentrações de 8% e 4% de volume celular, não tendo sido encontrada diferença nos resultados. Os dados foram analisados pelo indicador kappa e pelo χ2 de McNemar, adotando-se com ponto-de-corte o título 25 no 2-Me e 4 na RFC. O AAT-RIV apresentou concordância regular (kappa = 0,53) com o AAT e boa com os testes confirmatórios (kappa: 2-Me = 0,67; SAL+2-Me = 0,66; RFC = 0,76). O χ2 de McNemar apontou diferenças significativas entre os testes. A comparação entre os resultados do AAT-RIV e a condição verdadeira do animal, estabelecida pela combinação dos resultados das provas AAT, SAL+2-Me e RFC, resultou em uma sensibilidade relativa de 76,5%, com intervalo de confiança (95%) de 72,7% a 80,3%, e especificidade relativa de 100%. Conclui-se que o AAT-RIV poderia ser utilizado como teste confirmatório no diagnóstico sorológico da brucelose bovina, sendo os animais com resultado positivo considerados infectados e aqueles com resultado negativo submetidos a um dos dois testes confirmatórios adotados pelo PNCEBT. / Abstract: The purpose of the investigation was to evaluate the rose Bengal plate test in bovine serum after treatment with rivanol (RBPT-RIV) as a confirmatory test for brucellosis diagnosis. Serum samples from 1,061 bovine were analyzed by serological diagnostic techniques adopted by the Brazilian Program for Animal Brucellosis and Tuberculosis Control and Eradication: as screening test, the rose Bengal plate test (RBPT), and as confirmatory tests, the 2- mercaptoethanol plus standard tube agglutination test (STAT+2-Me), and the complement fixation test (CFT). RBPT-RIV was performed with 8% and 4% cellular concentration antigen, and there was no difference between the results. Data were analyzed by kappa statistic and McNemar χ2 (2-Me cut-off = titer 25, and CFT cutoff = titer 4). RBPT-RIV showed a moderate agreement (kappa = 0,53) with RBPT, and substantial agreement with the confirmatory tests (kappa: 2-Me = 0,67; STAT+2-Me = 0,66; CFT = 0,76). The McNemar χ2 showed significant difference among the tests. Comparing the RBPT-RIV results with the true condition of the animals, stablished by combining the results of RBPT, STAT+2-Me and CFT, the relative sensitivity was 76.5%, with a 95% confidence interval from 72,7% to 80.3%, and relative specificity of 100%. The results suggested that the RPBT-RIV is suitable to be used as a confirmatory test for brucellosis serological diagnosis; in this case, an animal testing positive should be classified as infected, and an animal testing negative should be tested by CFT or STAT+2-Me. / Mestre

Objetivou-se identificar os incentivos e barreiras que interferem para realizaÃÃo do teste anti-HIV e explorar quais os fatores individuais, comportamentais e programÃticos associados a testagem anti-HIV na populaÃÃo geral acima de 18 anos. Estudo seccional realizado com a populaÃÃo geral, residentes em Fortaleza, no perÃodo de 2011. Participaram do estudo 349 pessoas homens e mulheres, com 18 anos completos ou mais. A amostra foi selecionada aleatoriamente com base nos dados populacionais do municÃpio, a populaÃÃo foi sorteada por conglomerado, tendo como base as sete regionais executivas de Fortaleza. A partir da distribuiÃÃo de habitantes em cada regional, foram selecionados os bairros com maior proporÃÃo de habitantes e a partir desta proporÃÃo, foi estabelecida a quantidade de pessoas a serem entrevistadas por bairro. As entrevistas foram realizadas nas residÃncias dos entrevistados, no perÃodo de 4 semanas (05/07/2011 atà 29/07/2011). Os turnos foram manhà (08h-12h) e tarde (14h-18h). Utilizou-se um questionÃrio estruturado, inserido em um computador de bolso (Pocket-PC). Foram coletados dados relacionados à situaÃÃo sociodemogrÃficas, econÃmica, acesso aos serviÃos de saÃde, conhecimento sobre DST/aids, comportamento sexual, teste anti-HIV, violÃncia e uso de Ãlcool e drogas. Foi realizada anÃlise bivariada e multivariada hierÃrquica usando o software STATA 11.0. Dos 349 participantes, 208 (59,6%) nÃo realizaram o teste anti-HIV. Na anÃlise multivariada hierÃrquica, ser do sexo feminino e ter companheiro foram fatores protetores para a testagem anti-HIV. As demais variÃveis, ter 50 anos ou mais, nÃo ter ouvido falar do teste anti-HIV, nÃo saber onde faz o teste anti-HIV, nÃo receber preservativo e nunca ter doado sangue na vida foram significativamente associadas a nÃo realizaÃÃo da testagem anti-HIV. Os fatores comportamentais nÃo se mostraram associados com o desfecho. NÃo ver motivo e achar que nÃo tem risco para a infecÃÃo do HIV foram barreiras para que essa populaÃÃo nÃo realiza-se o teste. A certeza de nÃo estar infectado serviu como incentivo quanto barreira para a testagem, indicando a deficiÃncia no conhecimento sobre a doenÃa e, portanto a nÃo percepÃÃo de risco ao HIV/aids. Os achados tambÃm fazem indicam necessidade de estratÃgias adequadas para aumentar a oferta e divulgaÃÃo de serviÃos que ofertem o teste anti-HIV de forma sistemÃtica para a populaÃÃo em geral, incluindo os homens. TambÃm reforÃa a necessidade de maior treinamento para os profissionais da saÃde, no sentido de resguardar os resultados dos testes. / This study aimed to identify the incentives and barriers that interfere to perform the HIV test and to explore which individual, programmatic and behavioral factors associated with HIV testing in the general population over 18 years. Sectional study conducted with the general population residing in Fortaleza, 2011 period. The study included 349 people men and women, with 18 full years or more. The sample was randomly selected based on population data from the city, the population was selected by conglomerate with how the seven regional executive of Fortress basis. From the distribution of inhabitants in each region were selected neighborhoods with a higher proportion of inhabitants and from this ratio, the amount of people to be interviewed by district was established. The interviews were conducted in the homes of respondents, within 4 weeks (05/07/2011 to 29/07/2011). The shifts were morning (08h -12h) and late (14h-18h). We used a structured questionnaire inserted in a pocket computer (Pocket PC). Related to socio-demographic, economic status, access to health services, knowledge about STD/AIDS, sexual behavior, HIV testing, violence and alcohol and drug data were collected . Hierarchical bivariate and multivariate analysis was performed using STATA  11.0 software. Of the 349 participants, 208 (59.6 %) did not undergo HIV testing. In the hierarchical multivariate analysis, protective factors being female and having a partner were for HIV testing. The other variables , being 50 years or more , not having heard of HIV testing , does not know where the HIV testing , condom not receive and have never donated blood in life were significantly associated with not performing testing anti - HIV. Behavioral factors were not associated with outcome. Do not see reason and find that no risk for HIV infection were barriers for this population is not carried out the test. The certainty of not being infected served as an incentive barrier to testing, indicating the lack of knowledge about the disease and therefore the lack of perception of risk to HIV/AIDS. The findings also indicate the need to make appropriate strategies to increase the supply and distribution of services offered anti - HIV systematically test for the general population, including men. It also reinforces the need for more training for health professionals in order to protect the test results.