Nucleic acid hybridization (gene probe) and polymerase chain reaction (PCR) techniques have been used to detect viral nucleic acid in water. However, gene probe and PCR may not distinguish between infectious and noninfectious viruses. This study evaluated the ability of gene probe to detect viable poliovirus 1 (polio 1), from sterile and nonsterile groundwater, and the ability of PCR to detect infectious human immunodeficiency virus (HIV-1) from tap and wastewater. The plaque forming (BGM cells), and the tissue culture infectious dose fifty (TCID₅₀) (PLC/PRF/5 cells) procedures were used to detect infectious polio 1 and HIV-1, respectively. Detection of polio 1 by gene probe and cell culture was similar in nonsterile water and in filter sterilized water, but not in autoclaved water. These results suggest that in some natural waters, detection of polio 1 by gene probe may correlate to detection by cell culture procedures. Although detection of infectious HIV-1 by cell culture decreased gradually, until no virus could be found, detection by PCR remained positive throughout the study. Therefore, it was concluded that the use of PCR to assess the risk associated to the presence of HIV-1 in polluted waters, may not be adequate. The enteric adenovirus types 40 (Ead 40) and 41 (Ead 41) are considered the second most important cause of viral gastroenteritis in children, but their role as waterborne pathogens is uncertain. This study compared the survival of Ead 40 and Ead 41 with polio 1, and hepatitis A virus (HAV) in different types of water. The Enteric adenoviruses survived longer in tap and sea water than either polio 1 or HAV, but only slightly better in wastewater. These results suggest that the enteric adenoviruses may survive for prolonged periods in water, representing a potential route of transmission. This study evaluated also the concentration of Ead 40 by the filter adsorption-elution method. With negatively-charged filters, recovery efficiencies of 22, 36, and 38% were obtained from secondary sewage, tap and sea water, respectively. Using electropositive filters, Ead 40 was recovered from tap water with an efficiency of 26.5%. These results show that Ead 40 can be concentrated, from water, with an efficiency comparable to that of other enteric viruses.

<p>The HIV/AIDS pandemic poses the greatest threat to Africa's efforts to achieve its full potential in the social, economical and political spheres. Cognizant of its devastating consequences, various mechanisms have been designed to address the issue of HIV/AIDS in Africa. This thesis addressed the question: 'Are the legislations and policies of Ethiopia, Botswana and Uganda providing for various modalities of HIV testing consistent with human rights as enshrined under African Human Rights system?' The author of this dissertation critically analyzed the African human rights instruments and the relevant domestic legislation and policies of the three countries.</p>

<p>Nevirapine (NVP) is a cheap anti-retroviral drug used in poor countries worldwide, administered to pregnant women at the onset of labour to inhibit HIV enzyme reverse transcriptase. Viruses which may get transmitted to newborns are deficient in this enzyme, and HIV-1 infection cannot be established, thereby preventing mother to child transmission (MTCT). In some cases, babies get infected and positive selection for viruses resistant to nevirapine may be inferred. Positive selection can be inferred from sequence data, when the rate of nonsynonymous substitutions is significantly greater than the rate of synonymous substitutions.</p> <p>Unfortunately, it is found that available positive selection methods should not be used to analyse before- and after- NVP treatment sequence pairs associated with MTCT. Methods which use phylogenetic trees to infer positive selection trace synonymous and nonsynonymous substitutions further back in time than the short time duration during which selection for NVP occurred. The other group of methods for inferring positive selection, the pairwise methods, do not have appreciable power, because they average susbtituion rates over all codons in a sequence pair and not just at single codons. We introduce a simple counting method which we call the Pairwise Homologous Codons (PHoCs) method with which we have inferred positive selection resulting from NVP treatment in longitudinal HIV-1 reverse transcriptase sequences. The PHoCs method estimates rates of substitutions between before- and after- NVP treatment codons, using a simple pairwise method.</p>

The aim of this research was to implement and evaluate guidelines that will be used by treatment support counsellors in an attempt to increase client adherence to antiretroviral treatment.

HIV-1 has evolved a number of strategies in response to current anti-retroviral drugs and the selection pressure of humoral and cellular immunity. In particular, R5 viral strains that are essential for AIDS pathogenesis are very resistant to neutralization by antibodies. Therefore, the aim of this thesis was to develop synthetic nucleic acid ligands, aptamers, against gp120 of an R5 strain of HIV-1, with a view of using aptamers as novel neutralization molecules and analytical tools to study HIV-1 entry into target cells. The central hypothesis of this thesis was that aptamers by virtue of their small size and slow dissociation rates, compared to antibodies, would easily access and bind occluded gp120 neutralization sites. Using the SELEX protocol and SPR technology, I isolated 2'-Fluoro-pyrimidine-RNA aptamers against HIV-l_Ba-L monomeric gp120. Most of these aptamers not only bound gp120 with high affinities but also neutralized R5 primary isolates in human PBMC by 1,000 to 100,000-fold, truly unprecedented when compared with natural ligands such as antibodies. Some aptamers, like B4, defined a conserved site of gp120 that could not mutate to escape neutralization following stringent selection, in vitro, for breakthrough virus. This was consistent with subsequent findings that B4 aptatope (binding site) overlaps a poorly immunogenic but highly conserved CD4-induced epitope as determined by competition with 17b and 48d mAbs that map to this neutralization epitope on the gp120. This study was thus the first of its kind to describe neutralization of HIV-1 primary isolates by a ligand against the CD4-induced epitope. Most intriguing, although B4 potently neutralized HIV-1_Ba-L infection in PBMC, which is a mixed T cell and macrophage population, it modestly neutralized infection of the same virus in a purified culture of macrophages. These findings are intriguing in that they suggest that aptamers could be used to dissect unique sites on the virus that interact with target cell surface in ways that have not been revealed heretofore, and would help understand better HIV-1 entry pathways, especially in macrophages. Thus neutralizing aptamers such as these could be exploited to provide leads in developing alternative anti-HIV-1 drugs and a deeper understanding of the molecular interactions between the virus and its host cell.

Interleukin-l0 (IL-10) helps to limit the duration of potentially harmful inflammatory responses but has also been implicated in the persistence of a number of chronic viral infections. This thesis aimed to investigate the phenotype and function of mv -specific IL-l0-producing cells in chronic HIV-I infection, and the effect of IL-10 blockade on responses to candidate HIV -I vaccines. A cytokine capture assay was used to determine the HIV -specific cellular sources of IL- 10 in PBMC from 55 chronically infected individuals. A rare subset of CD8+ T cells was found to be the major HIV -I Gag-specific IL-10-producing population; these cells were restricted to ART-naive individuals and did not express the regulatory T cell markers CD25 or FoxP3 but could co-express IFN-y. A proportion of the population (median 48% and 9% respectively) expressed the P7 chain of the gut-homing integrin a4p7 and the chemokine receptor CXCR3, which mediates lymphocyte migration to sites of inflammation. Experimental depletion of Gag-specific IL-10+ CD8+ T cells did not affect T cell activation, or the production of cytokines such as IL-2 or IFN-y during short-term culture. However, depletion was associated with a significant increase in CD38 expression on CDI4+ monocytes, a trend towards increased HLA-DR expression on the same cells, and a significant increase in the concentration of the pro-inflammatory cytokine IL-6 in culture supernatants. There was also a significant increase in the number of HIV-infected (p24 antigen+) CD4+ T cells in cultures depleted of Gag- specific IL-10+ CD8+ T cells after 3 days, indicating that this population may contribute to control of viral replication. In order to determine the effect of IL-10 blockade on vaccine immunogenicity, IL-10R blocking antibody was administered to BALB/c mice prior to immunisation with two mV-I candidate vaccines, HIVA and HIVconsv. IL-10R blockade resulted in a trend towards increased IFN-y production by CD8+ T cells in response to the dominant H (Env) and P (Pol) epitopes of HIV A, and a significant increase in IFN-y ELISPOT responses to the subdominant Gl (Gag) epitope of HIV consv in vitro. Collectively, these data suggest that IL-10 producing cell populations may play critical but different roles in chronic infection and vaccination. Further research into how the timing of IL-10 responses affects disease outcome may allow IL-IO blockade to be explored as a therapeutic strategy in humans

Thesis (DPhil (Biomedical Science))--Cape Peninsula University of Technology, 2019. / Knowledge of population vulnerabilities to infectious diseases is key in managing many public health problems and for mapping appropriate strategies for prevention or intervention. A number of genes associated with resistance to HIV infection, such as the double deletion of 32 base pairs in the CCR5 gene , have been described and potentially account for lower HIV infections in some populations. The magnitude of the HIV pandemic in Sub-Saharan Africa warrants an investigation of the peculiar genetic factors that may have exacerbated its spread. An understanding of the genetic factors that are involved may aid in the development of specific strategies for prevention such as vaccine development, genetic counselling as well as gene therapy. The aim of this project was therefore to study the relationship between blood groups and HIV-infection in Botswana. HIV infection in Africa has not been linked to particular blood groups. The project was undertaken in two phases from December 2012 to December 2017. In the first phase, 346 subjects of known HIV status (negative or positive) were phenotyped for 23 erythrocyte antigens via standard scientific procedures. A Chi-square analysis was used to determine those antigens associated with increased or reduced risk of HIV infection. In the second phase, 120 samples were phenotyped for the protective blood group (RhC) and the risk-associated groups (Lub and P1). The samples were also characterized according to their laboratory results for viral load, lymphocyte sub-populations, complete blood count and blood chemistry, including total cholesterol. Some of the samples were also assessed for erythrocyte-associated viral RNA. Generally, the prevalence of the blood groups in the general population in Botswana did not differ with the known prevalence for Africans broadly. Three novel findings were established. First, the blood group Rh(C) was associated with a 40% risk reduction for HIV infection. Immunologically, carriage of the C antigen was associated with a more robust cell-mediated immunity as evidenced by enhanced cytotoxic T cell counts. Moreover, this antigen occurred with a frequency lower than 30% in all countries where HIV prevalence was high. There was therefore an inverse relationship between Rh(C) frequency and HIV prevalence. An examination of reports from previous studies revealed that the pattern was consistent in Africa, Europe, Asia, South America and Caribbean countries. It appears that the population frequency of this antigen explains, at least in part, a genetic factor that puts some African populations at higher risk for HIV infection. These results are novel in that Rh antigens have not been previously associated with immunity in any reports. Novel findings regarding the P1 blood group was its association with a double risk for HIV infection. While the plasma viral load did not differ between P1-positive and P1-negative subjects, P1-positive erythrocyte lysate yielded more viral RNA than P1-negative cells, implying more intracellular HIV RNA. Intra-erythrocytic viral RNA was detected even in patients with an undetectable plasma viral load. Glycosphingolipids, of which P1 is an example, have been documented to promote viral fusion to cells independent of CD4 receptors or other ligands. In at least one report, the presence of sphingolipids in lipid rafts was considered to be sufficient for viral fusion. The presence of viral RNA even in erythrocyte lysates corroborates this phenomenon and potentially explains the double risk of HIV infection observed. The occurrence of HIV RNA in erythrocyte lysate is a novel finding that suggests a new viral reservoir. Apparently, P1 has a high frequency among Africans and low in other races.

Orientador: Lenice do Rosario de Souza / Resumo: Ao analisar as atuais causas dos óbitos das pessoas que vivem com HIV/aids (PVHA), diferentemente da era pré-cART (terapia antirretroviral combinada), destacam-se doenças típicas do envelhecimento, tais como dislipidemias, doenças cardiovasculares, diabetes mellitus, entre outras, que aparecem de forma muito precoce nesta população. Tal fenômeno ocorre devido às persistentes ativação imune e inflamação crônica em PVHA, que são favorecidas pela interação da HMGB1 - high mobility group box protein-1 - e dos produtos finais de glicação avançada (AGEs), com seu receptor (RAGE), presente na superfície da membrana celular. Em sua forma solúvel, sRAGE é uma provável supressora da ativação imune por sequestrar os ligantes e evitar a interação deles com a forma transmembrana, anulando assim, seus efeitos. Além disso, a translocação microbiana e o estresse oxidativo têm sido estudados como potencializadores dessa cascata inflamatória e, em PVHA, níveis de sCD14 e de produtos de peroxidação lipídica, tais como o malondialdeído (MDA) e 8-isoprostano, estão elevados em relação aos indivíduos não-infectados, enquanto que o sistema antioxidante dos portadores do vírus, incluindo a capacidade antioxidante total (CAT), vitaminas e seus precursores, também é considerada deficiente. Portanto, esses marcadores estão relacionados, tanto com a própria evolução para a doença, quanto com o aparecimento e gravidade das comorbidades não-associadas a aids. Objetivos: avaliar a influência da cART e das... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Analyzing the current causes of deaths of people living with HIV/AIDS (PLWHA), it turns out that, unlike the pre-cART era (combination antiretroviral therapy), the highlights are typical manifestations of aging, such as dyslipidemia, cardiovascular disease and diabetes mellitus, which appear early in this population. This phenomenon occurs because of persistent immune activation and chronic inflammation in PLWHA, which are favored by the interaction of HMGB1 (high mobility group box protein-1) and AGEs (advanced glycation end-products), with the receptor RAGE, present in surface of the cell membrane. In its soluble form, sRAGE competes with the transmembrane receptor sequestering its ligands and preventing the activation of proinflammatory pathways. Furthermore, microbial translocation and oxidative stress have been studied as enhancers of this inflammatory cascade. Compared to the non-infected individuals, in PVHA the sCD14 and product levels of lipid peroxidation, such as malondialdehyde (MDA) and 8-isoprostane are increased, while their antioxidant system, including the total antioxidant capacity (TAC), vitamins and their precursors are deficient. Therefore, these markers are related both to the evolution of the disease itself, as with the onset and severity of non-AIDS comorbidities. Objectives: to evaluate the influence of cART and CD4+ T cells counts on plasma levels of sRAGE, AGEs, HMGB1, sCD14, cytokines, MDA, 8-isoprostane, TAC, vitamins, C-reactive protein (CRP) an... (Complete abstract click electronic access below) / Doutor

This study examines race differences and the relationship between religiosity/ spirituality and social support on quality of life (QOL) among people living with HIV/AIDS in Dallas/Ft. Worth, TX. The data were obtained from the Project VOICES research study conducted by the Center of Psychosocial Health Research at University of North Texas in 2003. This study explores the hypotheses that religiosity/spirituality and social support positively influences quality of life among people living with HIV/AIDS. The current study uses a diverse, gender-balanced sample consisting of African Americans (n = 156), aged 20-68, 47% male, 52% female and 1% transgendered) and Non-African Americans (n = 131), aged 19-65, 50% male, 46% female and 3% transgendered) (Caucasian, Latino, & others) to evaluate the relationship among variables of interest. Multiple regression analyses revealed that social support was a significant factor explaining quality of life (QOL) for African Americans when controlling for medical variables but did not for non-African Americans. Religiosity/spirituality was not found to be significant in this study. The implications of the findings are discussed.

Orientador: Lenice do Rosário de Souza / Banca: Alexandrina Sartori / Banca: Francisco Hideo Aoki / Resumo: O Brasil é um dos países mais afetados pelo HIV, com notificação de 608.230 casos acumulados de 1980 até junho de 2011, com a maior concentração na região Sudeste. Sabe-se que, entre muitos outros fatores a progressão para aids sofre influência de variáveis metabólicas, virológicas e imunológicas. Além disso, persistente ativação imune e contínuo estímulo inflamatório, mesmo durante a terapia antirretroviral (TARV) ou ausência de sintomatologia, podem levar ao desequilíbrio de várias citocinas e influenciar, potencialmente, a progressão da própria doença ou outras comorbidades, que são determinantes para aumentar a morbidade e mortalidade, associadas ou não à aids. Foram estudados 80 voluntários atendidos no Serviço de Ambulatórios Especializados e Hospital Dia "Domingos Alves Meira", FMB/UNESP e no Hemocentro de Botucatu, divididos em quatro grupos: 20 pacientes com infecção pelo HIV, virgens de tratamento (G1); 20 pacientes em uso de TARV com carga viral (CV) detectável (G2); 24 pacientes em uso de TARV com CV indetectável (G3); 16 indivíduos saudáveis, grupo controle (GC). O objetivo do estudo foi avaliar parâmetros imunovirológicos (contagem de linfócitos T CD4+, T CD8+ e dosagem da CV plasmática do HIV) de pacientes infectados pelo HIV, correlacionando citocinas séricas inflamatórias (IL-6, IL-17, TNF- e IFN-) e antinflamatória (IL-10) pelo método de ELISA, tempo de infecção, uso de TARV e outros exames laboratoriais (hemograma, perfil lipídico, glicemia, enzimas hepáticas, DHL, creatinina e PCR). As comparações das variáveis numéricas em relação aos grupos foram feitas utilizando o teste de Mann-Whitney, Kruskal-Wallis, seguido de teste de Dunn e análise da variância ANOVA, seguido de Tukey... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil is one of the most affected countries by HIV, reporting 608,230 cases that have accumulated from 1980 to June 2011 with the largest concentration in the south-east. It is known that, among many other factors, progression to AIDS is influenced by metabolic, virological and immunological variables. Moreover, persistent immune activation and continuous inflammatory stimulus, even during antiretroviral therapy (ART), or the absence of symptomatology may lead to the instability of various cytokines and potentially influence the progression of the disease itself or other comorbidities that are determinant to increase morbidity and mortality in association with AIDS or not. Eighty volunteers were assisted and studied in the Specialized Outpatient Service and Day Hospital "Domingos Alves Meira" at the Botucatu School of Medicine (FMB) - UNESP and at the Hemocenter of Botucatu. They were divided into four groups: 20 HIV-infected patients who had never been treated (G1); 20 patients using ART with a detectable viral load (VL) (G2); 24 patients using ART with undetectable VL (G3); 16 healthy individuals, control group (CG). The study aimed at evaluating immunovirological parameters (T CD4+, T CD8+ lymphocyte count and HIV plasma VL quantification) of HIV-infected patients and correlate them with inflammatory (IL-6, IL-17, TNF- and IFN-) and anti-inflammatory (IL-10) serum cytokines by the ELISA method, time of infection, ART use and other laboratory tests (hemogram, lipid profile, glycemia, liver enzymes, LDH, creatinine and CRP). Comparison of numeric variables in relation to the groups were performed by using the Mann-Whitney, Kruskal-Wallis test followed by Dunn's test, analysis of variance ANOVA and Tukey's test. Associations were made between variables and the study groups by analyzing contingency tables with the application of the... (Complete abstract click electronic access below) / Mestre