• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 335
  • 89
  • 17
  • 15
  • 8
  • 5
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 516
  • 516
  • 386
  • 221
  • 217
  • 204
  • 108
  • 93
  • 87
  • 85
  • 83
  • 80
  • 74
  • 72
  • 71
  • 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.
201

Factors influencing access to antiretroviral treatment in Benue State, Nigeria

Omenka, Charity Ochuole January 2010 (has links)
<p>The study utilized a qualitative case study design to explore the problem of poor access to ART in Benue State. PLWHAs, policy makers, program managers and health workers were involved in an effort to describe the factors influencing access to ART in the State. Semi structured interviews, exit interviews and focus group discussions were used. To analyse the findings, categorization was done into facilitators and barriers to access, in addition to the ways respondents believe these barriers can be overcome. Other sub-themes were also identified and sorted. Themes were linked to direct quotes from the respondents. Additional literature review was done to review available information on the themes identified. Facilitators of access included free cost and increased number of sites / beneficial effects of ART / disclosure, membership in a support group and having a treatment partner. Barriers included stigma and discrimination / hunger, poverty, transportation and opportunity costs / hospital factors / non-disclosure / inaccurate knowledge and perceptions about HIV and ART / certain religious beliefs and advice / coverage, capping of services and fear of non-availability of ART. In addition to stigma, patients bypass closer ART access points to further away hospitals because of business opportunities / financial assistance / perceived better standard of care and hope that a cure, when found, will be more accessible to patients in bigger hospitals.</p>
202

Exploration of Factors Associated with Poor Adherence amongst Patients Receiving Antiretroviral Therapy at Katutura State Hospital Communicable Disease Clinic in Khomas Region in Namibia.

Thobias, Anna. January 2008 (has links)
<p>Background: HIV/AIDS affects the health of millions of people world wide. According to the Joint United Nations Program on HIV/AIDS [UNAIDS], the number of people living with HIV globally has risen from 26 million in 2001 to 33.2 million in 2007. It is estimated that 2.5 million people were newly infected with HIV in 2007. The introduction of anti-retroviral therapy [ART] has brought hope to millions of people living with HIV and AIDS. More recently, the increased availability of treatment in many countries including Namibia has dramatically improved survival rates and lowered the incidence of opportunistic infections among HIV patients. Adherence to antiretroviral therapy (ART) is a fundamental attribute of excellent clinical HIV care and a key aspect in determining the effectiveness of treatment. Strict adherence to ART is vital to maintain low viral load and to prevent the development of drug resistant virus. Poor adherence is one of the key obstacles to successful ART for HIV positive patients. Literature has shown that there are various factors that hinder adherence to ART such as patient, service, community, family, socio-economic and work-related factors. Aim: This study aimed to describe the experiences of patients in the ART programme at Katutura State Hospital, Communicable Disease Clinic (CDC), in the Khomas region of Namibia and to explore factors that contribute to poor adherence.</p>
203

Pharmaco-immunological-virological dynamics in intrapartum HIV-1 transmission (PIVD study)

Singh, Michelle. January 2009 (has links)
Background: Multiple factors contribute to mother-to-child transmission (MTCT) of HIV-1, including virological, obstetric and biological factors. Other possible contributory determinants for high MTCT rates include immunological factors such as host genetics and viral genetic variations. Despite several therapeutic, prophylactic and obstetric interventions to reduce the proportion of infants infected during labour and delivery, mechanisms for intrapartum HIV-1 transmission remain elusive and current interventions, could, therefore remain sub-optimal. Much controversy has surrounded the correlation of HIV-1 RNA (viral load) in the systemic and genital compartments of women. The influence of short-term antiretroviral (ARV) drugs on genital tract HIV-1 is also unclear. At the time the present study was initiated, a regimen of maternal intrapartum and neonatal postpartum single-dose Nevirapine (sdNVP) was the standard of care for the prevention of mother-to-child transmission (PMTCT). In most low and middle-income countries, including South Africa, sdNVP has been documented as effective intrapartum HIV-1 prevention based on plasma pharmacokinetic levels, decreased viral loads (HIV-1 RNA) and reduced rates of intrapartum transmission, yet operational studies continue to report high intrapartum transmission rates despite the administration of sdNVP. As a result perinatal HIV-1 transmission remains a significant public health concern in several African countries. Aim: The primary aim of this study was to describe the pharmacological dynamics of Nevirapine in association with virological and immunological risk factors for intrapartum HIV-1 transmission in a South African PMTCT programme where sdNVP was the standard of care. Methods: Following regulatory approval from the Biomedical Research Ethics Committee at the University of KwaZulu-Natal (UKZN), one hundred and twenty pregnant HIV-infected women who received the sdNVP regimen for prevention of mother-to-child HIV-1 transmission were enrolled between April-December 2006 at King Edward VIII Hospital (KEH) in Durban. Blood and cervicovaginal lavage (CVL) samples were collected from women at pre-NVP (during pregnancy) and post-NVP dosing (during labour/delivery). In addition to infant blood sampling at birth (post-NVP), postnatal infants were assessed at four and six weeks postnatally. Pharmacological laboratory investigations involved measurement of NVP drug concentration by Tandem Mass spectrophotometry. Virological investigations comprised HIV-1 RNA (viral load) quantitation, HIV-1 drug resistance testing (HIV-1 transmitting women only) and HIV-1 DNA PCR testing (infants only). Immunological investigations were only undertaken in a selected case-control subset of HIV-1 transmitting women and their infants. In this component, laboratory investigations included the determination of CCL3 and CCL3-L1 gene copy numbers, identification of single nucleotide polymorphisms (SNP’s) and haplotype characterisation of the CCL3 gene. All women were also screened for the presence of sexually transmitted infections (STI’s) during pregnancy. Results: One hundred and twenty women were enrolled onto this study. Of these, 110 women delivered 117 live infants (103 singletons and 7 twin pairs). Twelve (10.9%) women transmitted HIV-1 to their infants, while 95 (86.0%) were classified as non-transmitters. As a result of seven twin deliveries, the infant cohort comprised of 117 infants in total. Following two separate DNA PCR tests, HIV-1 infection was identified in 14 (11.9%) of study infants while the remaining 90 (76.9%) were exposed-uninfected. HIV infection status remained unknown for 13 infants due to infant demise (1.7%), lost to follow-up (7.7%) or study withdrawal (1.7%). During active labour (sampling that was best representative of the intrapartum phase) and within 20 hours of dosing, the median NVP concentration of 1070 ng/ml in the maternal systemic compartment was almost 44 times higher than the NVP levels detected in the genital compartment [24.5 ng/ml] (p < 0.001). NVP drug levels were below the 100 ng/ml therapeutic target in seven (13.7%) of 51 plasma and in all 39 CVL samples. While no significant association was found between NVP concentration in the systemic compartment and HIV-1 transmission (p = 0.4), this association was statistically significant in the genital compartment(p = 0.02). The median plasma NVP level detected among infants at birth was 83 times above the IC50 WT (10 ng/ml) and eight times higher than the 100 ng/ml therapeutic target for NVP. More than 71.0% of the infants achieved NVP drug levels above the therapeutic target. In general, higher levels of HIV-1 RNA (viral load) were observed in maternal plasma when compared to CVL. Following intrapartum sdNVP dosing, reduction in HIV-1 RNA levels did occur, however R80.0% of the women experienced no change to their HIV-1 RNA levels in both systemic and genital compartments during active labour. These findings were further supported by the strong correlation observed when comparing pre and post-NVP HIV-1 RNA levels in both maternal systemic [r = 0.81, p < 0.0001] and genital compartments [r = 0.80, p < 0.0001] during active labour. HIV-1 transmitting women had significantly higher viral loads than their non-transmitting counterparts in systemic and genital compartments, before and after intrapartum sdNVP administration. In terms of perinatal transmission this observation was only statistically significant for plasma (p = 0.02) and not CVL (p = 0.7). Maternal viral load was inversely correlated with maternal CD4 cell counts in both systemic and genital compartments. Almost 40.0% of women in this study had at least one type of STI detected during pregnancy. Maternal STI’s were detected in four (66.6%) intrapartum transmitting women and in 38 (38.8%) of non-transmitting women. No significant association was observed between the presence of maternal STI’s and the risk for intrapartum MTCT (p = 0.2,RR: 2.90, 95% CI: 0.60-15.40). The presence of maternal STI’s was associated with higher median viral loads in both systemic and genital compartments of all women, independent of intrapartum HIV-1 transmission. Despite trial-like conditions and optimal sdNVP dosing, the overall MTCT rate in this exclusively formula-fed cohort was 11.9%, of which 50.0% were in utero and 50.0% were intrapartum HIV-1 transmissions. In utero and intrapartum MTCT rates were 5.9% and 5.9% respectively. Discussion/Conclusion: Detectable CVL HIV-1 RNA that correlated well with plasma HIV-1 RNA, in conjunction with sub-optimal NVP drug concentration in maternal CVL during active labour, suggests that intrapartum HIV-1 infected women continue to act as reservoirs for both vertical and horizontal HIV-1 transmission throughout the duration of pregnancy. These findings confirm that the role of sdNVP in PMTCT was primarily one of infant prophylaxis. This was further supported by relatively unchanged maternal HIV-1 RNA (viral load) during active labour, in both systemic and genital compartments. Early identification of women who need highly active antiretroviral therapy (HAART), and initiation of such therapy as early as possible during pregnancy, not only benefits maternal health but remains the best prophylaxis against mother-to-child HIV-1 transmission. Universal access to HAART and improving strategies to optimize coverage of the current dual ARV regimen sdNVP and Zidovudine for PMTCT remain urgent research priorities in several resource-limited settings. Ongoing STI counseling, intensive screening/testing of women and their partners together promotion of condom usage, safer sex practices and aggressive STI treatment are simple interventions with tremendous impact for PMTCT in resource-limited settings. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009.
204

Antenatal care for HIV positive women / Chantéll Doubell

Doubell, Chantéll January 2007 (has links)
Approximately 29.1% of South African women of childbearing age tested HIV positive during their first antenatal visit in 2006 (DoH, 2007). This rate of HIV amongst the women of childbearing age reinforces the importance of understanding the management of HIV during pregnancy. During antenatal visits the general health of the woman and her unborn baby is assessed and managed. Management includes antiretroviral therapy to the HIV infected women with a CD4 count below 200 cells/mm3, while women with a CD4 count above 200 cells/mm3 receive a single dose of nevirapine with the onset of labour provided to them by their local clinics. Currently, in Potchefstroom, women receive antenatal care at local primary health-care clinics and antiretroviral drugs at the antiretroviral clinic. There is little or no collaboration between the various clinics and the question arises if the needs of the women are being met. The aim of the research was to promote the health of HIV positive pregnant women by providing insight into the needs of these women and to formulate recommendations for antenatal care. The specific objective is to explore and describe the needs of HIV positive pregnant women regarding antenatal care. An explorative, descriptive, contextual design, following a qualitative approach was used during the research. Semi-structured interviews were used to collect data. Interview questions were compiled from the research problems. Before the commencement of data collection, permission was obtained from the district health manager and Potchefstroom Hospital. A total of sixteen (16) HIV positive women were interviewed after informed consent had been obtained. Data analysis was done after each session and themes were categorised according to the women's needs. From the interviews it was found that each woman has her own specific needs regarding antenatal care. The needs of the participants followed a similar pattern and for this reason it could be divided into various categories. These categories include a need for support, a need for education, a need for improved services and a need for a non-judgemental environment. Conclusions were drawn and recommendations were made for nursing practice, nursing education and nursing research. / Thesis (M.Cur.)--North-West University, Potchefstroom Campus, 2008.
205

Blood levels of selective antiretroviral drugs over a period of time, in Sprague-Dawley rats / Michael du Plooy

Du Plooy, Michael January 2008 (has links)
Selective antiretroviral! (ARV) drugs are primarily metabolized by cytochrome P450 (CYP) enzymes, characteristically predisposed to variation, and are therefore primarily responsible for ARV pharmacokinetic variability and associated drug interactions. For the majority of ARV drugs, the therapeutic window is narrow and imminent toxicities due to CYP inhibition or sub-therapeutic drug levels as a result of CYP induction is inevitable. Animals provide a metabolism replica to conduct detailed investigations. We endeavored to establish a rat model to screen for variability in metabolism of selective ARV drugs responsible for treatment failure and drug interactions, over time in the liver and serum. Male Sprague-Dawley rats (n = 24) were divided into 6 groups: methylcellulose, 160mg/kg/day (n = 24) (control); efavirenz, 160mg/kg/day (n = 18); ritonavir, 20 mg/kg/day (n = 18); ritonavir, 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day, (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18). Treatment duration varied from one day (single dose), 7 or 21 days. Blood samples were collected after decapitation on days 1, 7 and 21. A sensitive and rapid liquid chromatograph (LC) interfaced to a quadrupoie mass spectrometer (MS) and coupled with electrospray ionization (ESI) method was employed for the blood sample determinations. One single injection was required to simultaneously quantify efavirenz, lopinavir and ritonavir within the linear concentration range of 78 - 5000 ng/ml. Efavirenz blood levels increased statistically significantly (p < 0.05) from day 1 to day 21 with distinct steady state achievement prior to day 7. The levels of ritonavir increased statistically significantly (p < 0.05) from day 7 to 21 when administered alone and statistically significantly (p < 0.01) from day 1 to 21 when administered as the ritonavir/lopinavir combination. The levels of lopinavir also increased statistically significantly (p<0.01) from day 1 and 21 in the ritonavir/lopinavir combination. However, the inclusion of a P-glycoprotein inhibitor, verapamil, increased both the ritonavir (administered alone) and lopinavir blood levels significantly (p < 0.05) at day 1. The ritonavir levels were also significantly increased on day 21 (p < 0.05). When verapamil was added to the ritonavir/lopinavir combination the levels of ritonavir increased statistically significantly (p < 0.01) from day 1 to 21. A rat model can be used to detect changes in metabolism over time as measured by blood levels. The influence of drug interactions, such as verapamil, on ARV drug metabolism can be investigated by this model. These results will be substantiated by PCR liver results in the future. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2009.
206

Blood levels of selective antiretroviral drugs over a period of time, in Sprague-Dawley rats / Michael du Plooy

Du Plooy, Michael January 2008 (has links)
Selective antiretroviral! (ARV) drugs are primarily metabolized by cytochrome P450 (CYP) enzymes, characteristically predisposed to variation, and are therefore primarily responsible for ARV pharmacokinetic variability and associated drug interactions. For the majority of ARV drugs, the therapeutic window is narrow and imminent toxicities due to CYP inhibition or sub-therapeutic drug levels as a result of CYP induction is inevitable. Animals provide a metabolism replica to conduct detailed investigations. We endeavored to establish a rat model to screen for variability in metabolism of selective ARV drugs responsible for treatment failure and drug interactions, over time in the liver and serum. Male Sprague-Dawley rats (n = 24) were divided into 6 groups: methylcellulose, 160mg/kg/day (n = 24) (control); efavirenz, 160mg/kg/day (n = 18); ritonavir, 20 mg/kg/day (n = 18); ritonavir, 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day, (n = 18); Kaletra® (ritonavir/lopinavir), 20 mg/kg/day and verapamil 5 mg/kg/day (n = 18). Treatment duration varied from one day (single dose), 7 or 21 days. Blood samples were collected after decapitation on days 1, 7 and 21. A sensitive and rapid liquid chromatograph (LC) interfaced to a quadrupoie mass spectrometer (MS) and coupled with electrospray ionization (ESI) method was employed for the blood sample determinations. One single injection was required to simultaneously quantify efavirenz, lopinavir and ritonavir within the linear concentration range of 78 - 5000 ng/ml. Efavirenz blood levels increased statistically significantly (p < 0.05) from day 1 to day 21 with distinct steady state achievement prior to day 7. The levels of ritonavir increased statistically significantly (p < 0.05) from day 7 to 21 when administered alone and statistically significantly (p < 0.01) from day 1 to 21 when administered as the ritonavir/lopinavir combination. The levels of lopinavir also increased statistically significantly (p<0.01) from day 1 and 21 in the ritonavir/lopinavir combination. However, the inclusion of a P-glycoprotein inhibitor, verapamil, increased both the ritonavir (administered alone) and lopinavir blood levels significantly (p < 0.05) at day 1. The ritonavir levels were also significantly increased on day 21 (p < 0.05). When verapamil was added to the ritonavir/lopinavir combination the levels of ritonavir increased statistically significantly (p < 0.01) from day 1 to 21. A rat model can be used to detect changes in metabolism over time as measured by blood levels. The influence of drug interactions, such as verapamil, on ARV drug metabolism can be investigated by this model. These results will be substantiated by PCR liver results in the future. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2009.
207

The spectrum of HIV related nephropathy in KwaZulu-Natal : a pathogenetic appraisal and impact of HAART.

Ramsuran, Duran. January 2012 (has links)
Sub-Saharan Africa bears 70% of the global HIV burden with KwaZulu-Natal (KZN) identified as the epicenter of this pandemic. HIV related nephropathy (HIVRN) exceeds any other causes of kidney diseases responsible for end stage renal disease, and has been increasingly recognized as a significant cause of morbidity and mortality. There is nonetheless a general lack of surveillance and reporting for HIVRN exists in this geographical region. Consequentially, the aim of this study was to outline the histopathogical spectrum of HIVRN within KZN. Moreover, from a pathology standpoint, it is important to address whether HIVRN was a direct consequence of viral infection of the renal parenchyma or is it a secondary consequence of systemic infection. Additionally, an evaluation of the efficacy of Highly Active Anti-Retroviral Therapy (HAART) in combination with angiotensin converting enzyme inhibitors (ACE-I) was performed via a genetic appraisal of localized replication of HIV-1 in the kidney, ultrastructural review and immunocytochemical expression of a podocyte maturity and proliferation marker pre and post-HAART. Blood and renal biopsies were obtained from 30 children with HIV related nephropathy pre- HAART, followed-up clinically for a period of 1 year. This cohort formed the post-HAART group. Clinical and demographic data were collated and histopathology, RT-PCR, sequencing, immunocytochemistry and transmission electron microscopy was performed. The commonest histopathological form of HIVRN in children (n = 30) in KZN was classical focal segmental glomerular sclerosis (FSGS) presented in 13(43.33%); mesangial hypercellularity 10(30%); mesangial, HIV associated nephropathy 3(11%) and minimal change disease 2(6.67%). Post-HAART (n = 9) the predominant pathology was mesangial hypercellularity 5(55.56%); FSGS 3(33.33%) and sclerosing glomerulopathy 1(11.11%). This study also provides data on the efficacy of HAART combined with ACE-I. The immunostaining pattern of synaptopodin, Ki67 and p24 within the glomerulus expressed as a mean field area percentage was significantly downregulated in the pre-HAART compared to the post-HAART group respectively (1.14 vs. 4.47%, p = 0.0068; 1.01 vs.4.68, p < 0.001; 4.5% vs 1.4%, p = 0.0035). The ultrastructural assessment of all biopsies conformed to their pathological appraisal however, features consistent with viral insult were observed. Latent HIV reservoirs were observed within the podocyte cytoplasm but was absent in mesangial or endothelial cells. Real-Time polymerase chain reaction assays provided evidence of HIV-1 within the kidney. Sequence analysis of the C2-C5 region of HIV-1 env revealed viral diversity between renal tissue to blood. In contrast to a collapsing type of FSGS that occurs in adults, the spectrum of paediatric nephropathy in treatment-naive children within KwaZulu-Natal was FSGS with mesangial hypercellularity. Additionally, our study demonstrates podocyte phenotype dysregulation pre- HAART and reconstitution post therapy. Evidence of ultrastructural viral reservoirs within epithelial cells is supported by a genetic appraisal confirming the ubiquitous presence of HIV DNA in renal tissue. Moreover, sequence analysis showed viral evolution and compartmentalization between renal viral reservoirs to blood. Finally, the interplay of viral genes and host response, influenced by genetic background, may contribute to the variable manifestations of HIV-1 infection in the kidney in our paediatric population. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2012.
208

Immune dysregulation in HIV-1 infected lymphoid tissue /

Behbahani, Homira, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 6 uppsatser.
209

Studies on medical and immunological interventions in HIV-1 infection /

Hejdeman, Bo, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
210

Immunological and virological response to antiretroviral treatment (art) in patients infected with different HIV-1genetic subtypes /

Atlas, Ann, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.

Page generated in 0.1668 seconds