171 |
Predictive value of gene mutations as a diagnostic tool for ART resistance in a Zambian populationMaseko Phiri, Thabiso 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / Background: While Selection of reverse transcriptase (RT) mutation has been
reported frequently, protease (PR) mutations on antiretroviral therapy (ART) including
boosted Protease inhibitor (PI) have not been reported as much in Zambia. Affordable
in-house genotyping assays can been used to expand the number of patients receiving
drug resistance geno-typing, which can aid in determining prevalence of RT/PI
emerging mutations.
Methods: A previously published drug resistance genotyping assay was modified and
used to genotype RT and PR genes. 19 patients virologically failing first-line regimen
and 24 failing second-line regimen were studied to determine resistance patterns.
Virological failure was defined as failing to maintain <1000 copies/mL during ART.
Only major and minor RT and PR mutations (IAS-USA 2010) were considered for
analysis. The in-house assay was validated by comparing sequence data of 7 previously
ViroSeq tested samples and 5 randomly selected samples to determine reproducibility.
Results: The in-house assay efficiently amplified all 12 validation samples with the
lowest sample scoring 99.4% sequence homology. The most common RT mutation was
M184V (79% n=19) and (71% n=24) first and second-line respectively. No significant
differences were reported in all the other RT mutations between first-line and secondline
regimens. Drug resistant PI mutations (I54V, M46I and V82A all present 20.8%)
were only found in the second-line regimen and were insignificant, p= 0.0562.
Conclusion: The in-house assays can be used as alternatives for commercial kits to
genotype HIV-1C in Zambia without compromising test quality. The insignificant PI
drug resistant mutations which were found, despite virological failure in patients, could
indicate a possibility of other mutations within the HIV-1 genome that could reduce PI
susceptibility.
|
172 |
The applicability of the theory of planned behaviour in predicting adherence to antiretroviral therapy (ART) among a South African sampleSaal, Wylene Leandri 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The primary aim of the study was to determine the applicability of the theory of
planned behaviour (TPB) in predicting adherence to ART among South African
patients attending public health clinics. The second aim was to determine the
relationship between self-reported adherence and viral load. The results from the
hierarchical multiple regression analyses revealed that the linear combination of the
variables of the TPB significantly explained 12% of the variance in intentions to
adhere to ART. Perceived behavioural control was the only variable that significantly
predicted intentions to adhere to ART. The inclusion of perceived stigma was not a
useful addition to the model. The results also reflect the relationship between
intentions to adhere to treatment and self-reported adherence, which was not
significant. The TPB was unable to significantly account for variance in self-reported
treatment adherence. When perceived stigma was added to the TPB, the model was
still unable to significantly explain variance in self-reported adherence. Nonetheless,
attitudes towards treatment were the only variable that significantly accounted for
variance in self-reported treatment. It was concluded that interventions aimed at
improving adherence among South African patients attending public health clinics,
should aim to encourage positive attitudes towards treatment, should aim to increase
perceived subjective norms, should increase the patients’ perceptibility that they are
able to be adherent and should aim to decrease perceived stigma. Improving
adherence to ART can result in increasing the quality of life of patients living with
HIV/AIDS. / AFRIKAANSE OPSOMMING: Die primêre doel van die studie was om vas te stel of die teorie van beplande gedrag
(TPB soos voorgestel in die studie) antiretrovirale terapie (ART) nakoming onder
Suid-Afrikaanse pasiёnte by publieke gesondheidsklinieke kan voorspel. Die
sekondêre doel was om die verhouding tussen self-gerapporteerde volgehoue
behandeling en virale lading te bereken. Die uitslae van die hiёrargiese veelvuldige
regressie analise het getoon dat die linêere kombinasie van die veranderlikes van TPB
12% van die verandering in ART voornemens akkuraat kon voorspel. Waargenome
gedragsbeheer was die enigste veranderlike wat ART voornemens akkuraat kon
verklaar het. Die insluiting van waargenome stigma was nie beduidend ten opsigte
van die model nie. Geen beduidende verband tussen voorneme om met behandeling
vol te hou en self-gerapporteerde volgehoue-behandelingsgedrag word uitgebeeld.
Waargenome gedragsbeheer kon wel ‘n bydrae lewer om verandering in die
voorneme om met behandeling vol te hou verklaar. Die TPB kon egter nie ‘n
verduideliking bied vir die verandering in self-gerapporteerde volgehouebehandelingsgedrag
nie. Toe waargenome stigma by die TPB gevoeg is, was die
model steeds nie daartoe instaat om die verandering in self-gerapporteerde volgehouebehandelingsgedrag
te verklaar nie. Nietemin, houdings teenoor behandeling was die
enigste veranderlike wat verandering in self-gerapporteerde gedrag verklaar.
Daar is tot die gevolgtrekking gekom dat intervensies gerig op die verbetering van
volhoubare gedrag onder Suid-Afrikaanse pasiёnte wat openbare gesondheidsklinieke
bywoon,positiewe houding teenoor behandeling moet aanmoedig, subjektiewe norme
verhoog, die pasiёnte se persepsie dat hulle instaat is om volhoubare gedrag kan toon
moet verhoog en ook waargenome stigma moet verminder. Beter ART nakoming kan
lei tot ‘n toename in die MIV/VIGS pasiёnt se kwaliteit van lewe.
|
173 |
Intérêt du traitement antirétroviral précoce chez l’adulte infecté par le VIH en Afrique sub-Saharienne / Interest of early antiretroviral therapy in adults infected with HIV in sub-Saharan AfricaMoh, Desmorys- Raoul 17 December 2012 (has links)
Les pays africains au sud du Sahara ont vu leur nombre de patients sous traitement antirétroviral (ARV) croître de façon rapide depuis 2005. Si l’impact individuel et collectif de cette montée en puissance des traitements est positif dans l’ensemble, les défis demeurent nombreux en termes de dépistage, d’observance, d’adhésion aux soins, de résistance aux ARV, de dépendance vis-à-vis des bailleurs de fonds, et de disponibilité des personnels. Dans ce contexte, la question du moment idéal pour proposer le début du traitement ARV doit être abordée de façon médicale individuelle (quel est le rapport bénéfices/risques individuel à débuter à des seuils différents ?), mais également de façon collective en terme de bénéfices et risques pour la communauté, d’organisation des soins, d’analyse médico-économique, de prioritisation et d’équité. Cette thèse, qui est une thèse de recherche clinique, aborde le premier volet de la question, celui des bénéfices et des risques pour l’individu à débuter un traitement plus tôt. Sur ce sujet, le raisonnement a beaucoup évolué au cours des 15 dernières années. Après l’arrivée des multithérapies ARV à la fin des années 1990, la crainte de la toxicité des médicaments a d’abord incité à une approche prudente, et à recommander le seuil de début à 200 CD4/mm3 chez les personnes asymptomatiques. Cette crainte de la toxicité a conduit au début des années 2000 à essayer de pratiquer des « interruptions programmées » d’ARV, pour tenter d’obtenir le maintien au dessus d’un seuil de 200 CD4/mm3, tout en limitant l’exposition aux médicaments. Nous avons participé à un de ces essais d’interruptions programmées en Côte d’Ivoire, au cours duquel nous avons contribué à affiner les connaissances sur la toxicité des ARV (Moh, Antivir Ther 2005). Les essais d’interruptions programmées ont conduit à constater que : (i) les personnes qui interrompaient entre 350 et 250 CD4/mm3 avaient plus de risque de morbidité sévère que celles qui n’interrompaient pas, (ii) les personnes qui débutaient leur premier traitement avant 350 CD4/mm3 avaient moins de risque de morbidité que celles qui débutaient plus tard (Moh, AIDS 2007), et (iii) dans l’essai d’interruption Trivacan réalisé en Côte d’Ivoire, cette morbidité sévère intermédiaire était plus fréquente que dans l’essai SMART réalisé sur d’autres continents, et avait un spectre différent, dominé par la tuberculose et les maladies bactériennes sévères. Les conclusions de ces essais ont donc été que le traitement ARV devait être débuté beaucoup plus tôt que ce qui était auparavant recommandé, et que ceci était probablement encore plus vrai en Afrique sub-Saharienne que dans le reste du monde. En 2008, nous avons lancé en Côte d’Ivoire l’essai Temprano ANRS 12136, dont l’objectif est d’évaluer les bénéfices et risques d’un traitement ARV précoce avec ou sans 6 mois de prophylaxie par isoniazide (INH) chez des adultes infectés par le VIH-1 ayant entre 250 et 800 CD4/mm3. De Mars 2008 à Juillet 2012, 2076 adultes ont été inclus dans l’essai Temprano, dont le suivi se terminera en décembre 2014. L’état du suivi est bon, et les incidences de morbidité et mortalité actuellement constatées sont conformes aux hypothèses du protocole. La pratique de la prophylaxie par INH s’avère bien tolérée, et la procédure choisie par notre équipe (radiographie de thorax systématique et période tampon d’observation de un mois avant le début de l’INH) apporte une grande sécurité de prescription (Moh, Plos One, manuscrit en révision). Notre équipe a traversé une crise politico-militaire au 1er semestre 2011, qui n’a pas eu de retentissement sur la qualité de l’essai en cours. Cette crise a par contre eu des effets délétères pour les patients sous traitement ARV, puisque les échecs virologiques retardés sont significativement associés au fait d’avoir été sous traitement pendant cette période (Moh, manuscrit soumis). . / The African countries situated in the South of the Sahara have seen their number of patients under antiretroviral therapy (ART) grow rapidly since 2005. If the individual and collective impact of this rise of the treatments is positive overall, challenges remain in terms of screening, compliance, accession to care, resistance to ARTs, dependence on donors, and availability of the staff. In this context, the question of the ideal time to propose initiation of ART must be addressed in the individually medical way (what is the individual benefit-harm ratio to start at different thresholds?) but also collectively in terms of benefits and risks for the community, organization of care, medico-economic analysis, prioritization and equity. This thesis, which is a clinical research thesis, addresses the first part of the question, the benefits and risks for the individual to start treatment earlier. On this subject, the rationale has changed considerably over the past 15 years. After the arrival of ART multitherapy at the end of the 1990s, the fear of drug toxicity first prompted a cautious approach, and to recommend the threshold from beginning to 200 CD4/mm3 in the asymptomatic people. This fear of toxicity led in the early 2000s to try to practice "scheduled interruptions" of ARTs, to try to get the maintenance above a threshold of 200 CD4/mm3, in limiting exposure to the drug. We have participated in one of these trials of interruptions programmed in Côte d'Ivoire, in which we have helped to refine the knowledge on the toxicity of ARTs (Moh, Antivir Ther 2005). Testing scheduled interruptions led to see that: (i) persons who interrupted between 350 and 250 CD4/mm3 had greater risk of severe diseases than those who didn’t interrupt, (ii) persons who started their first treatment prior to 350 CD4/mm3 had less risk of morbidity than those who started later (Moh, 2007 AIDS), and (iii) in trial interruption Trivacan launched in Côte d'Ivoire, this intermediate severe morbidity was more frequent than in the SMART trial carried out on other continents, and had a different spectrum dominated by tuberculosis and severe bacterial diseases. The findings of these trials were that the ART should be started much earlier than was previously recommended, and that this was probably even truer in sub-Saharan Africa than in the rest of the world. In 2008, we launched in Ivory Coast the clinical trial, Temprano ANRS 12136, whose objective is to assess the benefits and risks of early ART with or without 6 months of prophylactic isoniazid (INH) in HIV-1 infected adults with CD4 250 and 800/mm3. From March 2008 to July 2012, 2076 adults were included in the trial Temprano, which follow-up will be completed by December 2014. The state of the follow-up is good, and the impact of morbidity and mortality currently observed are consistent with the assumptions of the Protocol. The practice of INH prophylaxis is well tolerated, and the procedure chosen by our team (systematic chest x-ray and period buffer observation of one month before the beginning of the INH) brings a prescription safety (Moh, Plos One manuscript in review). Our team went through a crisis politico-military 1St half 2011, which had no impact on the quality of the ongoing trial. This crisis has however had deleterious effects for patients under ART, since delayed virological failure are significantly related to the fact of having been under treatment during this period (Moh, submitted manuscript).
|
174 |
Vieillissement, infection par le VIH-1 & traitements antirétrovirauxPerrin, Sophie 14 December 2012 (has links)
L'utilisation des antirétroviraux (ART) a permis une augmentation de la durée des patients infectés par le VIH. Par ailleurs, les comorbidités, retrouvées au cours du vieillissement physiologique, semblent être plus fréquentes et d'apparition plus précoce ce qui pourrait suggérer une modification du programme de vieillissement chez ces patients. L'étude ANRS EP45 « Aging » (clinicalTrials.gov, NCT01038999) a pour objectif d'analyser chez des patients infectés par le VIH traités ou non les mécanismes cellulaires connus pour être impliqués dans le vieillissement. Les PBMC d'une cohorte de 130 patients infectés par le VIH 1 appariés en âge et en sexe avec 49 sujets séronégatifs ont été analysés. Trois centres spécialisés (Marseille, Montpellier, Nice) ont recruté des patients infectés naïfs ou sous première ligne de traitement. Les résultats présentés dans ce manuscrit rapportent l'analyse des mitochondries et des lamines nucléaires. La maturation de la lamine A ne semble pas modifiée dans les PBMC de patients sous traitement contenant un inhibiteur de protéase. Cependant, ces cellules pourraient ne pas être le modèle le plus adapté pour explorer ce volet. D'autre part, l'infection est responsable d'anomalies mitochondriales dans les lymphocytes, partiellement corrigées par les traitements antirétroviraux qui modifient les mitochondries des monocytes moins sensibles à l'infection. Bien que les secondes générations de ART soient moins toxiques que les premières, leurs effets secondaires pourraient néanmoins, sur « le long terme » et/ou généralisés à l'ensemble de l'organisme, être l'un des facteurs modifiant le programme de vieillissement de ces patients. / Antiretroviral therapy (ART) has increased life expectancy in HIV-infected patients. Moreover, some age-related disorders were found to be more frequent in HIV infected and treated patients than in an age-matched general population, suggesting a modified time course of aging in HIV infected patients. The ANRS EP45 « Aging » study (clinicalTrials.gov, NCT01038999) investigated in PBMC from HIV-1 infected patients under treatment or not the cellular mechanisms known to be involved in aging. The study was performed on a cohort of 130 patients HIV-1 infected age- and sex-matched with 49 seronegative control subjects. Patients never treated with ART (naïve) or under first line were recruited by 3 AIDS centres (Marseille, Montpellier, Nice). Results presented here describe explorations of mitochondria and nuclear lamin. No alteration of lamin A maturation was detected in PBMC from HIV-1 infected patients under treatment with protease inhibitor. However, these cells could not be the most appropriate models to investigate lamin A-related aging pathway. On another hand, mitochondrial modifications were observed in lymphocytes from HIV infected naive patients. These alterations were only partly rescued by ART whereas its induced slight changes in monocytes that appeared to be less sensitive to infection. While second generation of ART are less toxic than the first one, their secondary effects, due to long term exposure and/or generalised to different tissues, could lead to a modified time course of aging in HIV infected patients.
|
175 |
DESIGN, SYNTHESIS, AND BIOLOGICAL EVALUATION OF POTENT HIV-1 PROTEASE INHIBITORS WITH NOVEL BICYCLIC OXAZOLIDINONE AND BIS SQUARAMIDE SCAFFOLDSJacqueline N Williams (6859052) 16 August 2019 (has links)
<p>In 2018, the World Health Organization (WHO) reported approximately 37 million people are living with the Human Immunodeficiency Virus (HIV). Suppressing replication of the virus down to undetectable levels was achieved by combination antiretroviral therapy (cART) which effectively reduced the mortality and morbidity rates of HIV positive individuals. Despite the improvements towards combatting HIV/AIDS, no successful treatment exists to eradicate the virus from an infected individual. Treatment regimens are lifelong and prompt less than desirable side effects including but not limited to; drug-drug interactions, toxicity, systemic organ complications, central nervous system HIV triggered disorders and most importantly, drug resistance. Current therapies are becoming ineffective against highly resistant HIV strains making the ability to treat long-term viral suppression a growing issue. Therefore, potent and more effective HIV inhibitors provide the best chance for long-term successful cART. </p>
<p>HIV-1 protease (PR) enzyme plays a critical role in the life cycle and replication of HIV. Significant advancements were achieved through structure-based design and X-ray crystallographic analysis of protease-bound to HIV-1 and brought about several FDA protease inhibitors (PI). Highly mutated HIV-1 variants create a challenge for current and future treatment regimens. This thesis work focuses on the design, synthesis, and evaluation of two new classes of potent HIV-1 PIs that exhibit a novel bicyclic oxazolidinone feature as the P2 ligand and a novel bis squaramide scaffold as the P2/P3 ligand. Several inhibitors displayed good to excellent activity toward HIV-1 protease and significant antiviral activity in MT-4 cells. Inhibitors 1.65g and 1.65h were further evaluated against a panel of highly resistant multidrug-resistant HIV-1 variants and displayed antiviral activity similar to Darunavir. X-ray crystal structures of inhibitor 1.65a and inhibitor 1.65i were co-crystallized with wild type HIV-1 protease and solved at a 1.22 Å and 1.30 Å resolution and maintained strong hydrogen bond with the backbone of the PR enzyme. </p>
|
176 |
Genetic variation influencing mitochondrial DNA copy number and the development of sensory neuropathy in HIV-positive patients exposed to stavudineMarutha, Tebogo Rector January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand,
Johannesburg, in fulfilment of the requirements for the degree in Master of Science in the School of Molecular and Cell Biology
August 2017 / Antiretroviral therapy (ART) drugs such as stavudine (d4T) are known to have off-target side-effects, including the inhibition of DNA polymerase gamma which replicates mitochondrial DNA (mtDNA). ART-induced depletion of mtDNA copy number may cause mitochondrial toxicities such as sensory neuropathy (SN). Genetic variation in DNA polymerase gamma or in other nuclear genes influencing mtDNA replication and mtDNA copy number may therefore contribute to susceptibility to d4T-induced SN. DNA samples from 263 HIV-positive South African adults exposed to d4T were classified as cases with SN (n = 143) and controls without SN (n = 120). A total of 28 single nucleotide polymorphism (SNPs) were chosen in nuclear genes from the mtDNA replication pathway and from a GWAS paper examining SNP association with ART-induced SN (Leger et al. 2014). Genotyping was performed using Sequenom Mass Spectrometry. MtDNA copy number was determined using a qPCR assay. Associations between SN and genetic variants, between genetic variants and mtDNA copy number, and between mtDNA copy number and SN were evaluated in univariate and multivariate models using Plink v1.07 and GraphPad v7. Age and height were significantly different in the cases with SN vs controls without SN. In univariate analyses, three SNPs and two haplotypes were significantly associated with SN, three SNPs were associated with pain intensity and three haplotypes were significantly associated with mtDNA copy number. However, there were no significant associations with SN, pain intensity or mtDNA copy number after correction for multiple SNP testing. No significant difference in mtDNA copy number in cases vs. controls was observed. In conclusion variation in nuclear-encoded mitochondrial genes examined in the current study do not play a role in ART-related mitochondrial complications such as changes in mtDNA copy number, or occurrence of SN. / MT2018
|
177 |
Neurodevelopmental delays in children with perinatally acquired human immunodeficiency virus infection, with respect to antiretroviral therapy initiation and virological suppressionStrehlau, Renate January 2013 (has links)
A research report submitted to the Faculty of Health Sciences, the University of the
Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree
of
Master of Science in Medicine in Child Health Neurodevelopment
Johannesburg, 2013 / Human Immunodeficiency Virus (HIV) infection in infancy may influence the developing brain and lead to adverse neurodevelopmental consequences. We aim to describe the neurodevelopmental characteristics of a cohort of young children infected with HIV prior to antiretroviral therapy (ART) initiation and after achieving viral suppression. A retrospective analysis of data collected as part of a randomised equivalence trial between April 2005 and May 2009, at a hospital in Johannesburg, South Africa. 195 HIV-infected children under 2 years of age were assessed. A simple, inexpensive screening questionnaire (Ages and Stages Questionnaire - ASQ) was used to identify neurodevelopmental delays. The ASQ was administered prior to ART initiation, and again after viral suppression on a protease inhibitor-based regimen had been achieved. Median age pre-ART was 8.8 months (range 2.2 - 24.9), 53.9% were male. Mean time to viral suppression was 9.4 months (range 5.9 - 14.5) and the ASQ was administered to 108 caregivers at this time. Compared to pre-ART, at viral suppression, there was significant reduction in the proportion of children failing the gross motor (31.5% vs. 13%, p<0.01), fine motor (21.3% vs. 10.2%, p=0.02), problem solving (26.9% vs. 9.3%, p<0.001) and personal social (17.6% vs. 7.4%, p=0.02) domains. The proportion of children failing the communication domain was similar at each time point (14.8% vs. 12%, p=0.61). At time of viral suppression 10.2% failed at least one of the five domains.
Achieving viral suppression on ART resulted in significant improvements in the neurodevelopmental function of young HIV-infected children, however, neurodevelopmental
problems still persisted in a large proportion. Appropriate screening for neurodevelopmental delay and timely referral could help improve outcomes.
|
178 |
Prevalence of pheripheral neuropathy and effects of physiotherapeutic exercises on peripheral neuropathy in people living with Hiv on antiretroviral therapy in Rwanda.Tumusiime, David Kabagema 08 April 2015 (has links)
HIV-associated peripheral neuropathy (PN), and related functional limitations that affect the quality of life (QoL), may now be one of the most formidable challenges in the health care of people living with HIV (PLHIV). The most common PN is distal sensory polyneuropathy (DSP). It is likely that there is a high prevalence of PN among PLHIV in Rwanda. The available data on the prevalence of PN are poor and there are none on how PN is associated with functional abilities and the QoL of PLHIV, which can guide management. In addition, current management of PN is mostly related to symptomatic management and is mainly pharmacological which may not rehabilitate the neuromuscular function that has been affected by PN. This thesis planned to re-validate and adapt the lower extremity functional scale (LEFS) and the brief peripheral neuropathy screen (BPNS), establish the prevalence of PN, and determine the effects of physiotherapeutic exercises on PN, lower extremity functional limitations and QoL, among Rwandan PLHIV receiving antiretroviral therapy (ART).
Methods
Study 1 translated LEFS from English to Kinyarwanda, modified it accordingly, and tested its reliability among 50 adult PLHIV on ART. The study also piloted
|
179 |
Clinical outcome of HIV patients who commence antiretroviral therapy at different CD4 levelsMothapo, Khutjo Peter January 2011 (has links)
A research report submitted to the faculty of Health Sciences, University of the Witwatersrand,
Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Medicine
(Pharmacotherapy) / Background: The decision of when to start treatment in an HIV-infected individual has always been
problematic as far as CD4 count is concerned.
Aims: To determine the clinical outcome of patients who commence HAART at different CD4 cell
count levels.
Method: Retrospective analysis of records of a cohort of patients who are received ART at workplace
wellness clinics in three mines in Limpopo province from January 2003 to December 2009. Patients
were divided into three groups based on their baseline, group A (CD4 <100), group B (CD4 101-200)
and group C (CD4 201-250)
Each patient’s data was analyzed one year after his/her commencement.
Results: The percentage of patients who died in group A (16%) differs significantly from the
percentage of patients who died in group B (4%) (Fisher exact test p= 0.038) and also differ
significantly from the percentage of patients who died in group C (0%) (Fisher exact test p= 0.011).
The percentages of patients who developed TB in the three groups are 8%, 8% and 2.9% respectively.
When compared statistically, these percentages do not differ significantly (Fisher exact test
p=0.059).The percentages of patients with severe bacterial pneumonia in the three groups (2%, 2% and
0% respectively) do not differ significantly (Fisher exact test p=0,276).The percentage of hospital
admissions for patients in group A (18%) differ significantly from the percentage in group B (6%) and
the percentage in group C (6%) (Fisher exact test p= 0.05). The percentage of patients with weight loss
of more than 10% of baseline value in group A (24%) differ significantly from the percentage in group
B (4%) (Fisher exact test p= 0.003) and also differ significantly to from the percentage in group C (0%)
(Fisher exact test p= 0.001). The percentage of patients with undetectable viral load in group B (89%)
is significantly different from the percentage in group A (69%) (Fisher exact test p= 0.03) and is also
significantly different from the percentage in group C (61%) (Fisher exact test p= 0.008).The change in
mean CD4 cell count was found to be statistically significant within each group (paired t test,
p<0.0001), but the mean changes between the three groups (132,141 and 172) respectively, do not
differ significantly (ANOVA test).
Conclusion: Patients with baseline CD4 cell count of less than 100 have a poor clinical outcome when
compared to patients with baseline CD4 cell count of more than 100. Efforts must be made to identify
patients early before CD4 cell count fall to below 100 and preferably initiate HAART when CD4 cell
count is above 200.
|
180 |
Genetic variants of d4T drug transporters and dNTP pool regulators, and their association with response to d4T-ARTMoketla, Blessings Marvin January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science in Genetics.
Johannesburg, South Africa
2017 / Background: Stavudine (d4T) use is associated with the development of sensory neuropathy (SN), several mechanisms may underlie d4T-induced toxicity, including:
(1) Inter-patient genetic variability in the genes modulating the deoxynucleotide triphosphate (dNTP) pool sizes.
(2) Variation in intracellular ARV drug concentrations due to genetic variation in drug transporters.
In our study we examined the genetic variation in four stavudine transporter genes and seven genes regulating the deoxythymidine triphosphate (dTTP) synthesis and their associations with d4T-induced SN or CD4+ T cell count or mtDNA copy number.
Methods: We examined a cohort of HIV-positive South African (SA) adults exposed to d4T, including 143 cases with SN and 120 controls without SN. 26 single nucleotide polymorphisms (SNPs) from the literature were chosen, prioritised on being tagSNPs with minor allele frequency >5% in Kenyan Luhya (a proxy population for the SA Black population); SNP functional effects and suitability for multiplex analysis on the genotyping platform. Genotyping was performed using Sequenom mass spectrometry. A qPCR assay was used to measure the mtDNA copy number. Association of sensory neuropathy, CD4+ T cell count and mtDNA copy number with genetic variants was evaluated using PLINK.
Results: All 26 SNPs were in Hardy-Weinberg equilibrium (HWE) in both the cases and controls. SNP rs8187758 of the SLC28A1 transporter gene and a 3-SNP haplotype ABCG2 were significantly associated with CD4+ T cell count after correction for multiple testing (p = 0.043 and p=0.042 respectively), but were not significant in multivariate testing. No SNP remained significantly associated with SN or mtDNA copy number, after correction for multiple testing.
Conclusion: Variation in genes encoding molecular transporters of d4T may influence CD4+ T cell counts after ART. This study presents a positive step towards achieving personalized medicine in SA. / MT 2018
|
Page generated in 0.1069 seconds