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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.
31

Investigating depression and quality of life in adults diagnosed with HIV or AIDS

Loonat, Naadhira January 2009 (has links)
<p>HIV and AIDS are disease conditions that have led to high mortality rates in Southern Africa since the late 1970s. The socio-economic system has led to the unequal spread of resources&rsquo / and vulnerability and exposure to HIV is more prevalent in poorer communities. The added burden of life stresses cause for many to be isolated and stigmatised and are often not equipped with the necessary support and coping skills to deal with the magnitude of these circumstances. There is a high prevalence of mental disorders and especially depression amongst individuals infected with either HIV or AIDS. Research shows that stressful life events can impact HIV course progression and impacts the QoL of those infected with HIV or AIDS. Given the social and psychological context of HIV and AIDS, the aim of the study was to examine the relationship between depression and QoL in a sample of adults diagnosed with HIV or AIDS. This quantitative, cross-sectional study used the Becks Depression Inventory II (BDI II) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), to measure the variables concerned. This battery of&nbsp / questionnaires was administered to a purposive sample of adult individuals diagnosed with HIV or AIDS residing in a previously disadvantaged area in the Cape Metropole region. Using SPSS,&nbsp / data was analysed and descriptive and inferential statistics were conducted. The study found that there were more women than men with HIV or AIDS that were found to be depressed (mild, moderate and severe depression). Furthermore, the depressive state increased when the progression of the disease increased. There were generally no significant differences in the QoL&nbsp / experienced within various areas of life and overall life satisfaction experienced. However, the QoL experienced in work was lower. There was a significant relationship between the depressed state and QoL and life satisfaction experienced in household duties and tasks. The contribution of this study includes informing the larger research project, with regards to future treatment&nbsp / regimes. It will update statistics on the prevalence of depression and QoL of adults diagnosed with HIV or AIDS in the area. This study is framed within a biopsychosocial model and is&nbsp / theoretically underpinned by Beck&rsquo / s theory of depression. Key words: HIV, AIDS, adults, depression, quality of life (QoL), Beck Depression Inventory II (BDI II), Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), Antiretrovirals (ARV&rsquo / s), prevalence data, correlations.</p>
32

A Manufactured Solution? The Transfer of Technology for the Local Production of Affordable Antiretrovirals: Case Studies from Tanzania and South Africa

Wilson, Kinsley Rose 28 September 2009 (has links)
Statement of the issue: Facing large HIV-infected populations, Sub-Saharan African countries are producing antiretroviral (ARV) drugs under provisions of the World Trade Organization’s Agreement on the Trade-Related Aspects of Intellectual Property (TRIPS). Article 7 states that the protection of intellectual property should increase technology transfer to developing countries. This clause and the debate over domestic manufacturers’ ability to provide low-cost ARVs need examination. Methods: Case studies from ARV manufacturing initiatives in Tanzania and South Africa analyzed conditions affecting two outcomes: the type of technology transfer arrangement entered (voluntary license or imitation) and the affordability of ARVs. Data were collected and analyzed from documents, key-informant interviews, and observation. Chi-squared and phi correlation statistics were then conducted across developing countries to test the association of voluntary ARV licensure with TRIPS-compliant patents and domestic firm ownership (state or private). Results: Tanzania’s weak patent system and poorly-financed, partially state-owned firm dissuaded industry investment, but attracted a non-government organization to transfer technology through imitation. Donor-financed ARV tenders, however, restrict competition to international quality-accredited products not produced by the firm. Without large volumes and manufacturing capacity, it cannot achieve economies of scale to reduce prices below imported ARVs. In South Africa, civil society challenged the strong patent system and poor government commitment that inhibited an ARV rollout. This and a well-financed, publicly-traded firm leveraged voluntary licenses. With international quality approval, the firm increased first-line ARV affordability; however, limited domestic competition keeps treatment prices above those of neighbouring countries. A multi-country analysis found 321 generic ARV manufacturing initiatives in 86 firms across 25 developing countries. Voluntary ARV licenses had a strong positive association with TRIPS-patent compliance (ф=.56, p<.0001) and a weak negative association with state-ownership (ф=.19, p<.0001). Firms in South Africa and India were granted 77% of licenses and accounted for most quality accredited generic ARVs. Conclusion: Despite positive association, technology transfer does not readily result from patent protection, particularly to state-owned firms. Developing countries must enact policies to enable affordable ARVs; yet, they must be cautious using local production to increase ARV access, as most initiatives cannot compete with high-volume generic manufacturers.
33

Genotyping and antiretroviral resistance profile test from HIV-1 samples in patients with therapeutic failure from Cearà / Genotipagem e perfil de resistÃncia aos antiretrovirais do virus da imunodeficiÃncia tipo 1 em populaÃÃo com falha terapeutica no CearÃ, Brasil - 2002 a 2004

Melissa Soares Medeiros 03 February 2006 (has links)
Faculdade Christus / Introduction: Genotypic testing for HIV-1 drug resistance is useful for selecting antiretroviral drugs for patients developing treatment failure. O melhor entendimento da sua interpretaÃÃo facilitarà sua utilizaÃÃo como ferramenta mÃdica na terapÃutica do HIV. The optimal understanding of its interpretation will give an important tool for HIV treatment. Objective: To identify common combinations of resistance mutations and antiretroviral resistance profile. Methods: Between April 2002 and March 2004, 101 protease and reverse transcriptase (RT) sequences were determined for HIV-1 isolates from patients who were failing antiretroviral therapy. Resistance profile was obtained by Stanford program. Results: male were 76.2%, median age 38 years, CD4 media was 279.21 cells/mm3 and Viral load 4.49 log. Total of 31 mutational patterns were detected to protease inhibitor (IP), 49 to nucleoside RT inhibitor (NRTI), and 17 to nonnucleoside RT inhibitor (NNRTI). K65R was detected in 5.9% isolates. The most frequent mutations were L90M, M184V and K103N to IP, NRTI and NNRTI respectively. The main mutational patterns accounted for 49% of mutant sequences to IP, 38.5% to ITRN accounted and 40,9% to NNRTI. Patients with three or more therapeutic failure had worst resistance profile to all IP except for Lopinavir, and NRTI except for Tenofovir. High resistance to Lamivudine and NNRTI were independent of failure quantity. Conclusion: The best susceptibility was found to Lopinavir at IPâs class and to Tenofovir at ITRNâs. The main mutational patterns to IP, ITRN and NNRTI represented almost half of all patterns found. / A Genotipagem està sendo usada como mÃtodo para guiar a seleÃÃo de antiretrovirais em pacientes com falha terapÃutica. O melhor entendimento da sua interpretaÃÃo facilitarà sua utilizaÃÃo como ferramenta mÃdica na terapÃutica do HIV. Objetivo: Avaliar o perfil de resistÃncia aos antiretrovirais e identificar padrÃes mutacionais das seqÃÃncias de protease e TR do HIV-1. MÃtodos: Foram estudadas as sequÃncias de genes da protease e TR isoladas de 101 amostras de pacientes com HIV-1 em falha terapÃutica, entre abril/2002 a marÃo/2004, atravÃs de Genotipagem realizadas no CearÃ. O Banco de dados de Stanford foi utilizado para avaliaÃÃo de resistÃncia e SPSS versÃo 11 e Epi Info versÃo 6 para anÃlise estatÃstica. Resultados: Sexo masculino 76,2%, mediana de idade 38 anos, CD4 mÃdio de 279,21 cells/mm3 e Carga Viral 4.49 log. Na classe de Inibidores de Protease (IP) 31 padrÃes mutacionais foram encontrados, nos inibidores da transcriptase reversa anÃlogos de nucleosÃdeos (ITRN) 49 e para inibidores da transcriptase reversa nÃo anÃlogos de nucleosÃdeos (ITRNN) 17. As mutaÃÃes mais frequentes foram L90M, M184V e K103N para IP, ITRN e ITRNN espectivamente. A K65R foi detectada em 5,9% dos isolados. TrÃs ou mais falhas terapÃuticas apresentaram maior perfil de resistÃncia para todos os IPs exceto para Lopinavir, e para todos os ITRNs exceto para Tenofovir. Os seis principais padrÃes mutacionais para IPs equivaleram a 49% das sequÃncias, para ITRNs a 38,5%, e para ITRNNs os dois principais padrÃes corresponderam a 40,9%. Foram encontrados altos Ãndices de resistÃncia para ITRNNs independente da quantidade de falhas terapÃuticas. ConclusÃo: Nos IPs a menor resistÃncia encontrada foi ao Lopinavir e nos ITRNs ao Tenofovir. Os principais padrÃes mutacionais para IPs, ITRNs e ITRNNs representaram quase metade de todos os padrÃes de resistÃncia encontrados.
34

Desenvolvimento de metodologias alternativas para o controle de qualidade de anti-retrovirais em medicamentos utilizando eletroforese capilar / Development of alternative methods for the quality control of antiretroviral drugs by capillary electrophoresis

Luiz Antonio Zanolli Filho 29 June 2007 (has links)
Atualmente cerca de 38,6 milhões de pessoas estão infectadas pelo vírus da síndrome da imunodeficiência adquirida (AIDS) em todo mundo. O único modo de tratamento para esta doença é através da utilização de medicamentos responsáveis por atuarem em diferentes pontos do ciclo replicativo do vírus. No Brasil esta doença é tratada como de calamidade pública, sendo seu tratamento feito através do programa nacional DST/AIDS, o qual distribui gratuitamente os medicamentos necessários para o tratamento. Tendo em vista que vários desses medicamentos são formulados pela indústria local, esta dissertação tem como objetivo o desenvolvimento de métodos analíticos passiveis de aplicação na rotina farmacêutica para a qualificação de matérias primas, bem como o controle de qualidade dos produtos acabados. As determinações nas formulações de nevirapina e lamivudina foram realizadas por CZE, em eletrólitos ácidos com pH < 2,5. Para a lamivudina a determinação foi realizada em um eletrólito de 0,5 % de TEA, 20 mmol.L-1 de TRIS, pH = 2,5, ajustado com ácido fosfórico, com um tempo de análise inferior a 4 minutos. O método desenvolvido para a nevirapina foi conduzido em um eletrólito de 10 mmol.L-1 de fosfato de sódio (pH =2,5), com um tempo de análise de 3 minutos. Um outro método foi desenvolvido permitindo a determinação de efavirenz, estavudina e ritonavir por MEKC, utilizando-se um planejamento fatorial 23 com ponto central, um tempo inferior a 9 minutos em um eletrólito consituído de 20 mmol.L-1 de tetraborato de sódio, 20 mmol.L-1 de SDS e 30 % de acetonitrila. Os métodos desenvolvidos foram validados de acordo com os protocolos oficiais, mostrando que estes métodos apresentam características adequadas para a análise de formulações farmacêuticas. Outra abordagem foi feita utilizando o acoplamento da eletroforese capilar à espectrometria de massas, onde amostras de urina fortificadas foram analisadas. As análise foram conduzidas utilizando 400 mmol.L-1 de ácido fórmico e líquido auxiliar constituído de 0,5 % de ácido fórmico diluído com uma solução metanol:água (1:1), permitindo a identificação inequívoca dos fármacos. / There are approximately 38.6 million people infected by the immunodeficiency acquired virus (AIDS) over the world. The only way of treatment for this illness is administrating drugs that act in different points of the replicative cycle of the virus. In Brazil this illness is dealt as public calamity, being its treatment made through the national program DST/AIDS, which distributes free of charge necessary medicines for the treatment. Considering that many of these drugs are formulated by the local industries, this thesis has as objective the development of analytical methods to be applied in the pharmaceutical routine for the qualification of raw materials, as well as the quality control of the finished products. The analysis of drug formulations of nevirapine and lamivudine were carried by CZE, in acid electrolytes with pH < 2.5. For lamivudine the analysis was carried using an electrolyte composed of 0.5 % of TEA, 20 mmol.L-1 of TRIS, pH = 2.5, adjusted with phosphoric acid, with an analysis time less than 4 minutes. The method developed for the nevirapine, was lead in an electrolyte composed of 10 mmol.L-1 of phosphate buffer (pH = 2.5), with a time of analysis of 3 minutes. Another method was developed for efavirenz, estavudine and ritonavir by MEKC, using 23 a factorial design with central point, with an analysis time less then 9 minutes in an electrolyte of 20 mmol.L-1 of sodium tetraborate, 20 mmol.L-1 sodium dodecyl sulfate and 30 % acetonitrile. The developed methods were validated in accordance with official protocols, showing that these methods can be advantageously used in the analysis of pharmaceutical formulations. Another approach was to use the coupling of capillary electrophoresis with mass spectrometry, where fortified samples of urine had been analyzed. The analysis were performed using 400 mmol.L-1 formic acid and liquid sheath consisting of 0.5 % of formic acid diluted with a solution of (1:1) methanol:water, allowing the unequivocal identification detection of the drugs in the samples.
35

Investigating depression and quality of life in adults diagnosed with HIV or AIDS

Loonat, Naadhira January 2009 (has links)
Magister Psychologiae - MPsych / HIV and AIDS are disease conditions that have led to high mortality rates in Southern Africa since the late 1970s. The socio-economic system has led to the unequal spread of resources’ and vulnerability and exposure to HIV is more prevalent in poorer communities. The added burden of life stresses cause for many to be isolated and stigmatised and are often not equipped with the necessary support and coping skills to deal with the magnitude of these circumstances. There is a high prevalence of mental disorders and especially depression amongst individuals infected with either HIV or AIDS. Research shows that stressful life events can impact HIV course progression and impacts the QoL of those infected with HIV or AIDS. Given the social and psychological context of HIV and AIDS, the aim of the study was to examine the relationship between depression and QoL in a sample of adults diagnosed with HIV or AIDS. This quantitative, cross-sectional study used the Becks Depression Inventory II (BDI II) and the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), to measure the variables concerned. This battery of questionnaires was administered to a purposive sample of adult individuals diagnosed with HIV or AIDS residing in a previously disadvantaged area in the Cape Metropole region. Using SPSS, data was analysed and descriptive and inferential statistics were conducted. The study found that there were more women than men with HIV or AIDS that were found to be depressed (mild, moderate and severe depression). Furthermore, the depressive state increased when the progression of the disease increased. There were generally no significant differences in the QoL experienced within various areas of life and overall life satisfaction experienced. However, the QoL experienced in work was lower. There was a significant relationship between the depressed state and QoL and life satisfaction experienced in household duties and tasks. The contribution of this study includes informing the larger research project, with regards to future treatment regimes. It will update statistics on the prevalence of depression and QoL of adults diagnosed with HIV or AIDS in the area. This study is framed within a biopsychosocial model and is theoretically underpinned by Beck’s theory of depression. Key words: HIV, AIDS, adults, depression, quality of life (QoL), Beck Depression Inventory II (BDI II), Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q), Antiretrovirals (ARV’s), prevalence data, correlations. / South Africa
36

Intellectual Property and Access to Medicines: Patent Pooling as Access Enabler in Pharmaceutical Industry / Duševní vlastnictví a dostupnost léčiv: patentové pooly jako nástroje pro zvýšení dostupnosti ve farmaceutickém průmyslu

Nemkyová, Renata January 2014 (has links)
The doctrine of intellectual property is based on the assumption that the exclusivity to commercialize a novel product granted to an inventor creates incentives to conduct research. In some areas, however, intellectual property can constitute a barrier to development of social welfare. In the area of access to medicines in developing countries, the intellectual property-related problem can take two forms. When needed products are not being developed and thus do not exist, lack of availability occurs. Lack of accessibility, on the other hand, arises when necessary medicines do exist, but their prices are prohibitive for people from resource-poor countries. Based on a detailed analysis of the patent and trade environment in the pharmaceutical sector, the thesis examines the potential of patent pooling as a joint intellectual property management strategy to increase access to medicines within the existing international intellectual property system. Particularly, it analyzes the effects of an existing pharmaceutical pool, the Medicines Patent Pool, on accessibility of antiretroviral medicines in low and middle income countries.
37

Shared secrets – concealed sufferings : social responses to the AIDS epidemic in Bushbuckridge, South Africa

Stadler, Jonathan James 08 March 2012 (has links)
From the early 1990s, rates of HIV infection increased dramatically in South Africa and by the early 2000s, AIDS emerged as the main cause of death for adult South Africans. During the first half of the 2000s, the South African government’s response to this crisis was inadequate, marked by denial and delays in implementing prevention and treatment, resulting in thousands of preventable deaths. Yet, apart from the challenges posed by the predominantly urban-based Treatment Action Campaign (TAC), the absence of a social response to this crisis is notable, especially in rural settings. This scenario forms the broad backdrop to this ethnographic study that draws on participant observation and interviews undertaken over a three-year period (2002-2005) in KwaBomba village previously in the Gazankulu Homeland, now located in the Bushbuckridge municipality of the South African lowveld. An ethnographic perspective provides an intimate vantage point from which to view peoples’ experiences of the AIDS epidemic and their responses in context. This perspective draws attention to gaps in public health and biomedical understandings of the epidemic and suggests alternatives to these understandings. In Bushbuckridge, mortality and morbidity due to AIDS became visible in the late 1990s and early 2000s. Households were incapable of dealing with the burden of illness and death while the health services were often unwilling and ill-prepared. HIV prevention campaigns based on individual behaviour change were not well suited to a context in which HIV spread through sexual networks. Despite widespread awareness of the threat of AIDS, the disease was subjected to public censorship and AIDS suffering was concealed. Public discourses of AIDS were hidden within gossip and rumour and articulated as witchcraft suspicions and accusations. Although these discourses appear to deny and suppress the reality of AIDS, I suggest that they are active attempts to deal with the AIDS crisis: gossip and rumour allocate blame and construct a local epidemiology through which the epidemic can be surveilled; interpreting AIDS as witchcraft creates the possibility of avenging untimely death. These discursive forms are critical in informing individual and social responses to the AIDS epidemic. While the absence of public acknowledgement of AIDS as a cause of illness and death suggests denial and fatalism and appears to limit public action, subaltern discourses create shared secrets to manage the AIDS epidemic at the local level. Furthermore, these discourses may constitute a form of resistance against biomedical models of causality. Ethnographic enquiry at the local level offers a nuanced understanding of social responses to the AIDS epidemic. By examining forms of expression that lie outside the domain of public health, the thesis reveals how these constitute significant forms of social action in response to the epidemic. / Thesis (PhD)--University of Pretoria, 2012. / Anthropology and Archaeology / unrestricted
38

Incidence et facteurs de risque d’hémorragie intracrânienne et d’infarctus aigu du myocarde chez les personnes vivant avec le virus d’immunodéficience humaine

Durand, Madeleine 09 1900 (has links)
Objectif : Étudier le risque d’hémorragies intracrâniennes et d’infarctus du myocarde chez les patients vivant avec le VIH. Méthode : J’ai réalisé deux études de cohorte au sein de la banque de données de la Régie de l’assurance maladie du Québec. J’ai défini la cohorte des patients VIH-positifs, y ai étudié l’incidence d’hémorragies intracrâniennes et d’infarctus du myocarde, et l’ai comparée à une cohorte VIH-négative de même âge et de même sexe. J’ai étudié l’association entre ces évènements et l’exposition aux antirétroviraux au moyen d’études cas-témoin nichées dans la cohorte des patients VIH-positifs. Résultats : Le VIH est associé à un risque plus élevé d’hémorragies intracrâniennes, particulièrement au stade SIDA. Les patients VIH-positif sont également plus à risque de subir un infarctus du myocarde, et certains antirétroviraux sont associés à un risque plus grand. Conclusion : Les banques de données médico-administratives représentent un moyen valable d’étudier les comorbidités non-infectieuses chez les patients atteints du VIH. / Objective: To study the risk of intracranial hemorrhage, acute myocardial infarction and their determinants in HIV-infected patients. Methods: I conducted two matched cohort studies within the database of the Régie de l’assurance maladie du Québec. I identified the cohort of HIV-infected patients and compared the incidence of intracranial hemorrhage and myocardial infarction with that in an age and sex matched cohort of HIV-negative patients. To study the association between these events and exposure to antiretrovirals, I conducted two matched case-control studies nested in the HIV-positive cohort. Results: HIV-infected patients had increased risk of developing intracranial hemorrhage, particularly if they had AIDS. They were also at greater risk of suffering from myocardial infarction. Exposure to some antiretroviral drugs was associated with greater risk of myocardial infarction. Conclusion: Administrative health data can be used to study the non-infectious complications of HIV infection, but validation studies are needed to evaluate data quality.
39

Estudo da atividade e polimorfismos da Paraoxonase-1 em indivíduos infectados pelo vírus da imunodeficiência humana tipo-1 (HIV-1) tratados com inibidores de protease / Study of activity and polymorphisms of Paraoxonase-1 in individuals infected with human immunodeficiency vírus type-1 (HIV-1) treated with protease inhibitors

Cunha, Joel da 31 August 2012 (has links)
A enzima Paraoxonase-1 (PON1) possui atividades paraoxonase, arilestearase e lactonase, entre outras. É a mais estuda da família das PONs que é composta pela PON1, PON2 e PON3. Sugere-se, que todas atuam inibindo o processo de peroxidação lipídica de moléculas como a lipoproteína de baixa densidade (LDL) e alta densidade (HDL), caracterizando assim um possível papel anti-aterogênico. O gene da PON1 apresenta dois sítios polimórficos, com a troca de uma Gln192Arg (Q/R) e Met55Leu, que estão associados com diferenças na atividade e concentrações séricas da enzima. Por sua vez, indivíduos soropositivos para o HIV-1 apresentam alterações do metabolismo lipídico, que poderiam estar associados a alterações na atividade da PON1 e a terapia antirretroviral (TARV) com inibidores de protease (IP). O objetivo do estudo foi determinar as atividades séricas da PON1 e da arilestearase (ARE), e as freqüências alélicas dos polimorfismos genéticos da PON1 192QR e 55LM, e ainda, avaliar a correlação destes parâmetros com as alterações lipídicas em indivíduos soropositivos para o HIV-1 tratados com IP. No período de Setembro de 2009 até Junho de 2012, 174 indivíduos soropositivos e 46 soronegativos para o HIV-1 foram estudados. Foi realizada a genotipagem dos polimorfismos da PON1 192QR e 55LM através de PCR-RFLP. A atividade sérica da PON1/ARE foi avaliada por espectrofotometria empregando-se como substratos o paraoxon e o fenilacetato, respectivamente. O RNA-HIV-1 foi quantificado pelo método NASBA, e os linfócitos T-CD4+ e T-CD8+ por citometria de fluxo. Os níveis séricos de colesterol total, HDL, LDL, triglicérides (TG), ApoA1 e ApoB100 foram determinados e os anticorpos IgG anti-oxLDL por ELISA. A atividade sérica da PON1 foi inferior nos grupos de soropositivos, p<0,05, porém, a atividade ARE não apresentou diferenças entre os grupos estudados, p>0,05. Ambas as atividades não apresentaram relação com os genótipos PON1 192QR e 55LM, e estes genótipos apresentaram uma freqüência alélica semelhante ao grupo de soronegativos. Os níveis séricos de TG foram superiores nos grupos de soropositivos com TARV, p<0,05, enquanto o grupo tratado com IP apresentou níveis séricos de HDL e Apo-A1 inferiores aos demais grupos, p<0,05. Níveis séricos de Apo-B100, IgG anti-oxLDL, e o índice de risco aterogênico foram superiores no grupo tratado com IP, p<0,05. Concluí-se, que indivíduos soropositivos para o HIV-1 apresentaram alterações no metabolismo lipídico, principalmente nos tratados com IP, que adicionalmente apresentaram um maior índice de risco aterogênico e maiores níveis de anticorpos IgG anti-oxLDL. Estas alterações não apresentaram relação com os polimorfismos PON1 192QR e 55LM da PON1, e demonstraram que a atividade da enzima PON-1 esta diminuída em indivíduos soropositivos para o HIV-1 / The enzyme Paraoxonase-1 (PON1) has paraoxonase (PON), arylesterase (ARE) and lactonase activities, among others. It is the most studied member of PON family which is composed of PON1, PON2 and PON3. It is suggested that all members acts by inhibiting the peroxidation of lipid molecules as the low-density lipoprotein (LDL) and high-density lipoprotein (HDL), characterizing a potential anti-atherogenic effect. The PON1 gene has two mainly polymorphic sites, with an exchange of Gln192Arg (Q/R) and Met55Leu (L/M), which are associated with differences in activity and serum concentrations of the enzyme. In turn, seropositive individuals for HIV-1 show changes in lipid metabolism, which could be associated with changes in the activity of PON1 and highly active antiretroviral therapy (HAART) with protease inhibitors (PI). The aim of this study was to determinate the serum PON and ARE activities of PON1, the allele frequencies of PON1 192QR and PON1 55LM genetic polymorphisms and evaluate the correlation between these parameters and lipid abnormalities in seropositive patients for HIV-1 treated with IP. In the period from September 2009 until June 2012, 174 seropositive individuals and 46 soronegative individuals for HIV-1 were studied. We performed PON1 192QR and 55LM genotyping by PCR-RFLP. Serum activities PON and ARE of PON1 were evaluated by spectrophotometry using paraoxon and phenylacetate, respectively, as substrates. The HIV-1-RNA was quantified by the NASBA method, and lymphocytes T-CD4+ and T-CD8+, by flow cytometry. Serum levels of total cholesterol, HDL, LDL, triglycerides (TG), apoA1 and ApoB100 were determined. IgG anti-oxLDL antibodies were quantified by ELISA. The serum PON1 activity was lower in the seropositive group, p<0.05, however, ARE activity did not differ between groups, p>0.05. Both activities had no relation with the PON1 192QR and PON1 55LM genotype, and these individuals showed an allele frequency similar to the seronegative group. Serum levels of TG were higher in groups of HIV-positive with HAART, p<0.05, while the IP-treated group showed serum levels of HDL and ApoA1 lower than other groups, p <0.05. Serum levels of ApoB100, IgG anti-oxLDL antibodies, and atherogenic risk indices were higher in the group treated with PI, p<0.05. It was concluded that individuals HIV-1-infected showed changes in lipid metabolism, especially in those treated with IP, which additionally showed a higher rate of atherogenic risk and higher levels of IgG anti-oxLDL antibodies. These changes did not correlated with PON1 192QR and 55LM polymorphisms and demonstrated that the activity of PON1enzyme is decreased in individuals seropositive for HIV-1
40

Identificação de tendências evolutivas de marcadores de replicação viral e do status imunológico de pacientes vivendo com HIV: impacto da terapia anti-retroviral inicial sobre a resposta ao tratamento / Identifying trends in viral replication and immune status markers among patients living with HIV: impact of the initial antiretroviral therapeutic regimen on response to treatment

Courtouké, Claudia de Lello 08 May 2008 (has links)
INTRODUÇÃO: Na história natural da infecção por HIV, um período longo de aproximadamente dez anos precede o desenvolvimento da doença. No entanto, a interação vírus-hospedeiro é caracterizada por um evento dinâmico e não estático. Os modelos matemáticos foram cruciais para revelar o conceito de latência viral, visto que a replicação viral intensa e persistente foi demonstrada através da fase assintomática. Uma contribuição importante demonstrou que a maioria das células que produzia vírus tornava-se infectada em poucos dias. Nosso estudo visa avaliar indivíduos infectados por HIV, investigando o impacto dos esquemas anti-retrovirais iniciais recebidos por eles (monoterapia versus bibiterapia versus HAART) no curso da doença. MÉTODOS: Usamos um banco de dados com 1391 pacientes, atendidos em serviço de referência em São Paulo, com pelo menos seis mensurações consecutivas de carga viral. Utilizamos o modelo linear aplicado à carga viral no plasma e ao número de células CD4+ em sangue periférico para classificar os desfechos em favoráveis ou desfavoráveis. Validamos a escolha da aproximação linear de acordo com dois critérios baseados na estatística c2 e em ( ) 2 2 Q . A associação de cada um desses desfechos e o esquema anti-retroviral inicial prescrito foi avaliada após a análise dos coeficientes angulares da reta de regressão para a carga viral e para o número de células T CD4+. RESULTADOS: Para a maioria dos pacientes com carga viral não-detectável durante o seguimento, nenhum esquema anti-retroviral inicial foi capaz de modificar o desfecho. Os resultados indicam efeito benéfico dos esquemas anti-retrovirais para apenas 20% dos pacientes com viremia persistente. Desfechos desfavoráveis foram associados à maioria dos pacientes com recuperação de viremia tanto de forma transiente ou como no final do seguimento. Para a maioria dos pacientes com viremia intermitente, mas com regularidade no final do seguimento: ou não-detectável ou detectável, os resultados mostram, respectivamente, desfechos favorável e desfavorável, independentemente do primeiro esquema anti-retroviral prescrito. Desfechos distintos foram apresentados por pacientes com carga viral oscilatória, ora detectável ora não-detectável, destacando-se que para a maioria dos pacientes que iniciou o tratamento com duas ou três drogas o desfecho foi favorável, ao passo que aquela que iniciou com uma única droga, exibiu desfecho desfavorável. CONCLUSÕES: As ferramentas da Matemática demonstraram, com sucesso, que o esquema anti-retroviral prescrito inicialmente não está associado à resposta ao tratamento para a maioria dos pacientes analisados. Os desfechos favoráveis podem estar associados a intervenções médicas envolvendo reforço da adesão ou mesmo troca de esquemas terapêuticos durante o seguimento. O aparecimento de linhagens resistentes à terapia antiretroviral e a seleção positiva dessas linhagens pode ser uma explicação para os desfechos desfavoráveis obtidos / In the natural history of HIV infection, a ten-year long asymptomatic period precedes disease development. However, viral-host interaction is a dynamic rather than a static event. Mathematical models have been crucial to rule out the concept of viral latency, since persistent and intense viral replication was demonstrated throughout the asymptomatic phase. One important contribution revealed that most plasma viral producing cells had become infected few days before. The present study aims at evaluating such an interaction in HIV infection, investigating the impact of initial antiretroviral regimens (mono therapy vs. double therapy vs. highly active antiretroviral therapy - HAART) in the course of disease. Using an available database with at least six sequential CD4+ cell counts and HIV viral load assessments of 1391 patients under clinical follow-up at a reference care centre in São Paulo, we classified patients according to a linear approximation model of plasma viral loads and peripheral blood CD4+ cell counts into favourable and unfavourable outcomes. We validated the linear approach according to two criteria, based on c2 and ( ) 2 2 Q . Association between each of these outcomes and the initial prescribed antiretroviral regimen was sought after analyzing the viral load and CD4+ cell counts slopes from the linear model. No particular initial regimen was shown associated with plasma viral undetectability during follow-up. The results point out for a beneficial effect of ART regimens for only 20% patients with persistent vireamia. Unfavourable outcomes were associated with most patients who resumed vireamia transiently or at the end of follow-up. For most patients with intermittent vireamia ending with an undetectable or a detectable viral load, the results indicate favourable and unfavourable outcomes, respectively, regardless of the initial prescribed antiretroviral regimen. Distinct outcomes occurred among patients with oscillatory viral loads, standing out the fact that for most patients who were started on therapy with two or three drugs had a favourable outcome. In contrast, most of those who were started on antiretroviral monotherapy had an unfavourable outcome. Mathematical tools have successfully demonstrated that the initially prescribed ART regimen was not associated with the long-term response to therapy for most analysed patients. Favourable outcomes can be associated to medical interventions including reinforcement of adherence or even changes in therapeutic regimens during follow-up. Emergence and positive selection of ART-resistant viral strains might be hypothesized as implicated in unfavourable outcomes

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