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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.
271

Improving anti-viral T cell therapies by knockout of the NR4A family of transcription factors

Schweitzer, Lorne 08 1900 (has links)
Les infections virales peuvent demeurer latentes pendant plusieurs décennies et se réactiver pendant des périodes d’immunosuppression. Les receveurs de greffes hématopoïétiques sont particulièrement susceptibles compte tenu de l’immunosuppression importante qui est nécessaire pour prévenir le rejet ou la maladie du greffon contre l’hôte, souvent pendant des périodes prolongées. La plupart de ces infections ne peuvent pas être traitées avec des médicaments antiviraux, et lorsque c’est possible, les traitements peuvent amener de la résistance. L’injection de cellules T spécifiques contre les virus provenant de donneurs sains est un traitement efficace pour traiter ces infections virales potentiellement mortelles ou les cancers qu’elles causent. Cependant, la persistance de ces cellules est limitée en partie par la stimulation antigénique chronique qui cause l’épuisement des cellules T. En éliminant les membres de la famille de récepteurs orphelins NR4A, qui favorisent l’épuisement et limitent la différenciation en cellules mémoires durables, notre but est de rendre ces cellules transférées plus persistantes et efficaces. Nos données à ce jour montrent que l’élimination du récepteur NR4A3 n’ altère pas la différenciation mémoire ni la production de cytokines effectrices. Cependant, l’absence de NR4A3tend à amener une diminution le l’expression du marqueur d’épuisement Tim-3, ce qui suggère que l’on peut prévenir l’épuisement et ainsi améliorer les thérapies cellulaires en ciblant les membres de la famille des récepteurs NR4A. / Viral infections can lay dormant for decades only to reactivate in periods of immune suppression. Transplant recipients are particularly susceptible to these infections as they require intensive immunosuppression to prevent rejection or graft-versus-host-disease, often for the rest of their life. Most of these infections cannot be treated with currently available antiviral medications and those that do can develop resistance. Virus-specific T cells (VSTs) are a treatment that uses expanded T cells to treat these infections by infusing donor cells into patients with life-threatening viral infections and cancers. However, these cells have a limited lifespan in part due to chronic antigen stimulation causing T cell exhaustion and lack of persistence. By knocking out members of the NR4A family of orphan receptors, which favour exhaustion and limit differentiation into long-lasting memory cells, we aim to make these transferred cells more persistent and effective. NR4A3 knockout did not alter memory differentiation or effector cytokine production but did result in a trend towards decreased expression of the exhaustion marker Tim-3, which indicates that targeting members of this family may improve clinically translatable cellular therapies.
272

Opportunistic Scheduling Using Channel Memory in Markov-modeled Wireless Networks

Murugesan, Sugumar 26 October 2010 (has links)
No description available.
273

Prescribing cotrimoxazole prophylactic therapy (CPT) before and after an electronic medical record system implementation in two selected hospitals in Malawi

Gadabu, Oliver Jintha 11 1900 (has links)
Opportunistic infections (OIs) have been identified as a leading cause of poor outcomes in the ARV therapy (ART) programme. In order to reduce OIs, the Malawi, MoH introduced routine prescription of cotrimoxazole preventive therapy (CPT) in 2005. The MoH also started scaling up a point-of-care electronic medical record (EMR) system in 2007 to improve monitoring and evaluation. This study had the following objectives: i) to quantify prescription of CPT before and after implementing EMR; ii) to compare the difference in CPT prescription before and after implementing EMR. A historically controlled study design was used to compare CPT prescriptions one year before, and one year after implementation of the EMR at two health facilities. The data indicated that there was a significant (P <0.001) decrease in CPT prescribing at one health facility and a significant increase in CPT prescription at another. / Health Studies / M.A. (Public Health)
274

從Patent Trolls議題看美台專利改革與解決之道 / The Solution of Patent Trolls Issues in Light of Patent Reform and Cases in the U.S. and Taiwan

李明峻, Lee, James Unknown Date (has links)
近年來在美國有一種”新興產業”崛起,部份非專利權實施者NPE,專門尋找實際生產商品或提供服務的知名企業為對象,以提出專利侵權訴訟的方式,加上持有法院核發之禁制令,威脅被告以達到強迫授權或合解的目的,一般稱之為「Patent Trolls」。 按專利制度的二大政策目標,一為提供發明人發明的誘因,一為鼓勵發明人揭露其發明技術內容,而Patent Trolls投機性授權模式所造成的問題,是否會破壞專利法之立法目的,而降低企業投資創新研發的誘因,乃值得觀注且為有待解決的議題。 故本文之主要目的乃從美國與台灣之專利改革與實務判決,探討Patent Trolls之解決之道。 / Recently there is a “new industry” in the U.S., some NPEs brought patent infringement suits against famous enterprises, which manufacture product or supply service and threatened with injunction, commonly called “Patent Trolls”. Among the two policy objects of patent law, one is giving the inducement to invent, the other is encourage inventors to disclose their inventions. Whether the problems caused by the opportunistic licensing models of Patent Trolls would cause damage to the object of patent law and decrease the driving force to invent of the enterprises is an issue worth observing and solving. Consequently, the object of this thesis is to discuss the solution of the Patent Trolls issues in light of Patent Reform and cases in the U.S. and Taiwan.
275

Machine Learning and Statistical Decision Making for Green Radio / Apprentissage statistique et prise de décision pour la radio verte

Modi, Navikkumar 17 May 2017 (has links)
Cette thèse étudie les techniques de gestion intelligente du spectre et de topologie des réseaux via une approche radio intelligente dans le but d’améliorer leur capacité, leur qualité de service (QoS – Quality of Service) et leur consommation énergétique. Les techniques d’apprentissage par renforcement y sont utilisées dans le but d’améliorer les performances d’un système radio intelligent. Dans ce manuscrit, nous traitons du problème d’accès opportuniste au spectre dans le cas de réseaux intelligents sans infrastructure. Nous nous plaçons dans le cas où aucune information n’est échangée entre les utilisateurs secondaires (pour éviter les surcoûts en transmissions). Ce problème particulier est modélisé par une approche dite de bandits manchots « restless » markoviens multi-utilisateurs (multi-user restless Markov MAB -multi¬armed bandit). La contribution principale de cette thèse propose une stratégie d’apprentissage multi-joueurs qui prend en compte non seulement le critère de disponibilité des canaux (comme déjà étudié dans la littérature et une thèse précédente au laboratoire), mais aussi une métrique de qualité, comme par exemple le niveau d’interférence mesuré (sensing) dans un canal (perturbations issues des canaux adjacents ou de signaux distants). Nous prouvons que notre stratégie, RQoS-UCB distribuée (distributed restless QoS-UCB – Upper Confidence Bound), est quasi optimale car on obtient des performances au moins d’ordre logarithmique sur son regret. En outre, nous montrons par des simulations que les performances du système intelligent proposé sont améliorées significativement par l’utilisation de la solution d’apprentissage proposée permettant à l’utilisateur secondaire d’identifier plus efficacement les ressources fréquentielles les plus disponibles et de meilleure qualité. Cette thèse propose également un nouveau modèle d’apprentissage par renforcement combiné à un transfert de connaissance afin d’améliorer l’efficacité énergétique (EE) des réseaux cellulaires hétérogènes. Nous formulons et résolvons un problème de maximisation de l’EE pour le cas de stations de base (BS – Base Stations) dynamiquement éteintes et allumées (ON-OFF). Ce problème d’optimisation combinatoire peut aussi être modélisé par des bandits manchots « restless » markoviens. Par ailleurs, une gestion dynamique de la topologie des réseaux hétérogènes, utilisant l’algorithme RQoS-UCB, est proposée pour contrôler intelligemment le mode de fonctionnement ON-OFF des BS, dans un contexte de trafic et d’étude de capacité multi-cellulaires. Enfin une méthode incluant le transfert de connaissance « transfer RQoS-UCB » est proposée et validée par des simulations, pour pallier les pertes de récompense initiales et accélérer le processus d’apprentissage, grâce à la connaissance acquise à d’autres périodes temporelles correspondantes à la période courante (même heure de la journée la veille, ou même jour de la semaine par exemple). La solution proposée de gestion dynamique du mode ON-OFF des BS permet de diminuer le nombre de BS actives tout en garantissant une QoS adéquate en atténuant les fluctuations de la QoS lors des variations du trafic et en améliorant les conditions au démarrage de l’apprentissage. Ainsi, l’efficacité énergétique est grandement améliorée. Enfin des démonstrateurs en conditions radio réelles ont été développés pour valider les solutions d’apprentissage étudiées. Les algorithmes ont également été confrontés à des bases de données de mesures effectuées par un partenaire dans la gamme de fréquence HF, pour des liaisons transhorizon. Les résultats confirment la pertinence des solutions d’apprentissage proposées, aussi bien en termes d’optimisation de l’utilisation du spectre fréquentiel, qu’en termes d’efficacité énergétique. / Future cellular network technologies are targeted at delivering self-organizable and ultra-high capacity networks, while reducing their energy consumption. This thesis studies intelligent spectrum and topology management through cognitive radio techniques to improve the capacity density and Quality of Service (QoS) as well as to reduce the cooperation overhead and energy consumption. This thesis investigates how reinforcement learning can be used to improve the performance of a cognitive radio system. In this dissertation, we deal with the problem of opportunistic spectrum access in infrastructureless cognitive networks. We assume that there is no information exchange between users, and they have no knowledge of channel statistics and other user's actions. This particular problem is designed as multi-user restless Markov multi-armed bandit framework, in which multiple users collect a priori unknown reward by selecting a channel. The main contribution of the dissertation is to propose a learning policy for distributed users, that takes into account not only the availability criterion of a band but also a quality metric linked to the interference power from the neighboring cells experienced on the sensed band. We also prove that the policy, named distributed restless QoS-UCB (RQoS-UCB), achieves at most logarithmic order regret. Moreover, numerical studies show that the performance of the cognitive radio system can be significantly enhanced by utilizing proposed learning policies since the cognitive devices are able to identify the appropriate resources more efficiently. This dissertation also introduces a reinforcement learning and transfer learning frameworks to improve the energy efficiency (EE) of the heterogeneous cellular network. Specifically, we formulate and solve an energy efficiency maximization problem pertaining to dynamic base stations (BS) switching operation, which is identified as a combinatorial learning problem, with restless Markov multi-armed bandit framework. Furthermore, a dynamic topology management using the previously defined algorithm, RQoS-UCB, is introduced to intelligently control the working modes of BSs, based on traffic load and capacity in multiple cells. Moreover, to cope with initial reward loss and to speed up the learning process, a transfer RQoS-UCB policy, which benefits from the transferred knowledge observed in historical periods, is proposed and provably converges. Then, proposed dynamic BS switching operation is demonstrated to reduce the number of activated BSs while maintaining an adequate QoS. Extensive numerical simulations demonstrate that the transfer learning significantly reduces the QoS fluctuation during traffic variation, and it also contributes to a performance jump-start and presents significant EE improvement under various practical traffic load profiles. Finally, a proof-of-concept is developed to verify the performance of proposed learning policies on a real radio environment and real measurement database of HF band. Results show that proposed multi-armed bandit learning policies using dual criterion (e.g. availability and quality) optimization for opportunistic spectrum access is not only superior in terms of spectrum utilization but also energy efficient.
276

New empirics on transdisciplinary political economics : essays on the economics of democratic modalities / Nouvel empirisme en économie politique transdisciplinaire : essais sur les effets économiques des modalités démocratiques

Mandon, Pierre 20 December 2017 (has links)
L'objet de la présente thèse concerne l'étude de l'impact économique de trois modalités démocratiques, à savoir (i) l'agenda électoral, (ii) l'affiliation partisane des dirigeants en place dans un cadre de multipartisme, et (iii) les changements de gouvernance constitutionnellement définis. Afin d'introduire notre étude, nous décrivons la relation qui existe entre les modalités démocratiques et la démocratie directe d'une part et la politique budgétaire d'autre part, aux Etats-Unis sur la période 1790-2014 dans l'Introduction Générale. Dans le Chapitre 2 nous étudions l'effet authentique et potentiellement néfaste des cycles politico-budgétaires. Notre méta-analyse suggère que les dirigeants nationaux manipulent effectivement le budget dans un but de réélection mais l'ampleur du phénomène est largement exagérée par la littérature. Toutefois, le biais de publication mis en lumière s'est significativement réduit lors des 25 dernières années de recherches. Dans le Chapitre 3 nous étudions comment l'affiliation partisane des gouverneurs américains affecte le statut de pauvreté des immigrants, aux Etats-Unis, sur la période 1994-2014. Pour ce faire, nous comparons le niveau de pauvreté des immigrants dans les Etats gouvernés par les Démocrates au niveau de pauvreté des immigrants constaté dans les Etats gouvernés par les Républicains. En accord avec la littérature sur l'affiliation partisane, nous trouvons que les immigrants ont plus d'opportunités de sortir de la pauvreté sous les Démocrates que sous les Républicains. Une analyse formelle de médiation révèle que nos résultats empiriques sont médiatisés par un meilleur accès au marché du travail et possiblement de meilleures rétributions du travail, pour les immigrants. Dans le Chapitre 4 nous cherchons à vérifier l'évolution des notations souveraines lors des périodes d'inauguration des nouveaux dirigeants sur un échantillon de 18 pays d'Amérique Latine et des Caraïbes ayant des systèmes présidentiels. A partir de données de panel journalières s'étendant du 1er janvier 1994 au 31 décembre 2014, nous trouvons que les notations souveraines sont de meilleure qualité durant les périodes d'inauguration anticipées comparées aux autres périodes d'inauguration. En outre, nos résultats montrent que durant ces périodes d'inauguration anticipées, les notations sont encore meilleures lorsque le dirigeant entrant (i) est économiquement de droite, (ii) dispose d'un diplôme universitaire d'un pays de l'OCDE, (iii) a un parcours professionnel traditionnel, (iv) a une approche non populiste, et (v) dispose de marges électorales de victoire importantes. Il apparaît également un biais de genre potentiel à la faveur des nouveaux dirigeants de sexe masculin. En prenant avantage d'un modèle de durée et de régressions de Cox -- modèle à risque proportionnel, nous mettons en lumière que les périodes d'inauguration des dirigeants affectent également la probabilité instantanée de dégradation des notations souveraines. Enfin, dans la Conclusion Générale nous explorons les racines des pensées antisystèmes en Occident, puis nous discutons des avantages et inconvénients de quelques formes alternatives de démocratie, à savoir (i) la démocratie directe, (ii) le tirage au sort, et (iii) le développement participatif comme bien public. Finalement, nous explorons les controverses concernant les formes alternatives de démocratie sur l'agora virtuelle que constitue Twitter. / The aim of the present dissertation is to empirically investigate the economic impact of three democratic modalities, namely (i) the electoral agenda; (ii) the partisan affiliation of incumbents in a multipartism framework; and (iii) constitutionally defined leadership changes. To introduce the scope of the dissertation we describe the democratic modalities and direct democracy behind the U.S. fiscal policy from 1790 to 2014, in the General Introduction.In Chapter 2 we study the genuine detrimental effect of political budget cycles. Our meta-analysis suggests that national leaders do manipulate fiscal tools in order to be re-elected, but to an extent that is significantly exaggerated in the literature. The publication selection bias highlighted has nonetheless been reduced during the past 25 years of research. In Chapter 3 we investigate how governors' partisan affiliation affects the poverty status of immigrants to the U.S for the period 1994-2014. To this end, we compare the poverty outcomes of immigrants in states ruled by Democratic governors relative to the outcomes for those in states ruled by Republican governors. Consistent with the literature on partisan affiliation, we find that immigrants are more likely to get out of poverty in states with Democratic governors than states with Republican governors. A formal mediation analysis reveals that the empirical results are mediated through better access to the labor market and possibly through higher wages and labor earnings for immigrants. In Chapter 4 we assess whether sovereign credit ratings change during the inauguration periods of incoming leaders, on a sample of 18 Latin American and Caribbean countries with presidential systems. Building on a daily panel dataset covering the period from January 1, 1994 to December 31, 2014, we find that credit ratings are better during anticipated inauguration periods compared to other inauguration periods. Moreover, our results reveal that, during anticipated inauguration periods, incoming leaders with (i) an economically right-wing orientation; (ii) an OECD college degree; (iii) a traditional professional background; (iv) a non-populist approach; and (v) large electoral margins of victory are associated to even better ratings. There also appears to be a potential gender bias effect in favor of male incoming leaders. Last but not least, the quality of the credit rating also matters. In the General Conclusion we explore the roots of anti-systemism in the West, then we discuss some alternative forms of democracy, and we explore the controversies regarding the alternative forms of democracy on the virtual \emph{agora} of Twitter.
277

Medicine prescribing patterns in HIV/AIDS and non HIV/AIDS children : a comparative study in the private health care sector of South Africa / Mocke, M.

Mocke, Martlie January 2010 (has links)
Background: According to the United Nations AIDS Reference Group (2010) and World Health Organization (2010:2), approximately 33 million people in the world had HIV/AIDS in 2009 of which 2.6 million were children. More than 30 million of these individuals resided in low– and middle–income countries. South–Africa had the highest prevalence of HIV/AIDS in the world with an estimated 5.2 million patients in 2009 (Statistics South Africa, 2010:2). Although the prevalence of human immunodeficiency virus (HIV) infection among children is reported to be high, little is known about other medication administrated concomitantly with their antiretroviral drugs. Objective: The general objective of this study was to investigate possible changes in the medicine prescribing patterns of HIV/AIDS and non–HIV/AIDS children. Methods: A quantitative, retrospective drug utilisation review was performed utilising medicine claims data of a South African pharmacy benefit management company. Data for a four–year period (Jan 1, 2005 to Dec 31, 2008) were analysed. The study population consisted of all children <=12 years divided into those receiving ARVs (designated HIV positive) and those without (designated HIV negative). Descriptive statistics such as average mean, standard deviation, t–test, d–values, and two way frequency tables were used to describe the results. Data were analysed using the Statistical Analysis System ® SAS 9.1 ® programme. Results: The study population (children <= 12 years) represented 16.2% (n = 197 323) of the total population in 2005, 15.4% (n = 193 346) in 2006, 15.6% (n = 142 049) in 2007 and 13.3% (n = 98 939) in 2008. Children with HIV/AIDS represented 0.2% (n = 197 323) of the study population in 2005 and increased to 0.4% (n = 98 939) in 2008, whereas the percentage of children without HIV/AIDS decreased from 99.8% (n = 197 323) in 2005 to 99.6% (n = 98 939) in 2008. The total number of HIV/AIDS children that also received other medication concomitantly with their ARVs increased from 96.5% (n = 402) in 2005 to 97.2% (n = 427) in 2008. Males with HIV/AIDS who used other medication represented 52.6% (n = 388) in 2005 and increased to 53.3% in 2008 while female HIV/AIDS patients represented 47.4% in 2005 and decreased to 46.7% in 2008. Prescriptions containing three ARV items represented 69.5% (n = 2 969) of the total number of prescriptions received by HIV/AIDS patients in 2005 and decreased to 67.7% in 2008. The combination of lamivudine, nevirapine and stavudine were the three products that appeared most frequently on prescriptions for HIV/AIDS children in the age group 0 <= 1 years and 1 <= 5 years from 2005 to 2008. In the age group 5 <= 12 years the combination most frequently prescribed was lamivudine, nevirapine and zidovudine. HIV positive children received 6.2 ± 4.62 prescriptions for other medication (non–ARVs) per year during 2005 compared to HIV negative children with 3.9 ± 3.71 (p < 0.0001, d = 0.5). In 2008 HIV positive children received 6.4 ± 5.02 prescriptions per year compared to HIV negative patients who received 4.36 ± 4.05 prescriptions (p < 0.0001, d = 0.5) in 2008. HIV negative children received more central nervous system items, endocrine items and autacoids than HIV positive children, whereas HIV positive children received more respiratory system agents, dermatological, ear, nose throat and antimicrobials items. Conclusion: The study showed that HIV positive children received significantly more prescriptions for other medication per year compared to their HIV negative counterparts. The top pharmacological groups mostly prescribed to both groups were respiratory agents, antimicrobials, analgesics, dermatological and ear, nose and throat items. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2012.
278

Medicine prescribing patterns in HIV/AIDS and non HIV/AIDS children : a comparative study in the private health care sector of South Africa / Mocke, M.

Mocke, Martlie January 2010 (has links)
Background: According to the United Nations AIDS Reference Group (2010) and World Health Organization (2010:2), approximately 33 million people in the world had HIV/AIDS in 2009 of which 2.6 million were children. More than 30 million of these individuals resided in low– and middle–income countries. South–Africa had the highest prevalence of HIV/AIDS in the world with an estimated 5.2 million patients in 2009 (Statistics South Africa, 2010:2). Although the prevalence of human immunodeficiency virus (HIV) infection among children is reported to be high, little is known about other medication administrated concomitantly with their antiretroviral drugs. Objective: The general objective of this study was to investigate possible changes in the medicine prescribing patterns of HIV/AIDS and non–HIV/AIDS children. Methods: A quantitative, retrospective drug utilisation review was performed utilising medicine claims data of a South African pharmacy benefit management company. Data for a four–year period (Jan 1, 2005 to Dec 31, 2008) were analysed. The study population consisted of all children <=12 years divided into those receiving ARVs (designated HIV positive) and those without (designated HIV negative). Descriptive statistics such as average mean, standard deviation, t–test, d–values, and two way frequency tables were used to describe the results. Data were analysed using the Statistical Analysis System ® SAS 9.1 ® programme. Results: The study population (children <= 12 years) represented 16.2% (n = 197 323) of the total population in 2005, 15.4% (n = 193 346) in 2006, 15.6% (n = 142 049) in 2007 and 13.3% (n = 98 939) in 2008. Children with HIV/AIDS represented 0.2% (n = 197 323) of the study population in 2005 and increased to 0.4% (n = 98 939) in 2008, whereas the percentage of children without HIV/AIDS decreased from 99.8% (n = 197 323) in 2005 to 99.6% (n = 98 939) in 2008. The total number of HIV/AIDS children that also received other medication concomitantly with their ARVs increased from 96.5% (n = 402) in 2005 to 97.2% (n = 427) in 2008. Males with HIV/AIDS who used other medication represented 52.6% (n = 388) in 2005 and increased to 53.3% in 2008 while female HIV/AIDS patients represented 47.4% in 2005 and decreased to 46.7% in 2008. Prescriptions containing three ARV items represented 69.5% (n = 2 969) of the total number of prescriptions received by HIV/AIDS patients in 2005 and decreased to 67.7% in 2008. The combination of lamivudine, nevirapine and stavudine were the three products that appeared most frequently on prescriptions for HIV/AIDS children in the age group 0 <= 1 years and 1 <= 5 years from 2005 to 2008. In the age group 5 <= 12 years the combination most frequently prescribed was lamivudine, nevirapine and zidovudine. HIV positive children received 6.2 ± 4.62 prescriptions for other medication (non–ARVs) per year during 2005 compared to HIV negative children with 3.9 ± 3.71 (p < 0.0001, d = 0.5). In 2008 HIV positive children received 6.4 ± 5.02 prescriptions per year compared to HIV negative patients who received 4.36 ± 4.05 prescriptions (p < 0.0001, d = 0.5) in 2008. HIV negative children received more central nervous system items, endocrine items and autacoids than HIV positive children, whereas HIV positive children received more respiratory system agents, dermatological, ear, nose throat and antimicrobials items. Conclusion: The study showed that HIV positive children received significantly more prescriptions for other medication per year compared to their HIV negative counterparts. The top pharmacological groups mostly prescribed to both groups were respiratory agents, antimicrobials, analgesics, dermatological and ear, nose and throat items. / Thesis (M.Pharm. (Pharmacy Practice))--North-West University, Potchefstroom Campus, 2012.
279

Nutritional factors associated with oral lesions in HIV disease and TB infection

Phooko, Puleng M. (Puleng Mpopi) 12 1900 (has links)
Thesis (Mnutr)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: Problem Definition: In the context of HIV/AIDS malnutrition is almost universal among children, and of the adverse effects of Protein Energy Malnutrition, the most frequent seems to be the occurrence of opportunistic infections with micro-organisms such as oral Candida. Objective: The aim of this study was to determine the nutritional status of children with oral complications in relation to HIV/AIDS as well as the effects of the oral lesions on nutritional status. Subjects/setting: The subjects of study were 24 children co-infected with TB and HIV who were admitted consecutively to the paediatric ward of Brooklyn Chest Hospital in Cape Town, South Africa. The nutritional status of the children was assessed over a maximum period of six months by nutrient intake, anthropometric status, and by biochemical parameters and clinical and oral examination on admission and at discharge from hospital. Results: Children with HIVand TB infection presenting with or without oral lesions were similarly malnourished throughout the period of hospitalization. There was no improvement in the nutritional status as indicated by height and weight measurements. Throughout the time of hospitalization, 7% of the children had a combination of stunting, underweight and wasting. Average nutrient intake was not found to be higher than the Recommended Dietary Allowance (RDA) in any of the children. At the time of admission to hospital and at discharge, carbohydrate intake provided most of the daily energy (36% and 42%, the difference not being statistically significant). There was a significant increase in the intake of energy (p=O.04) and a decrease in total fat intake (p=O.03) at discharge. Although not significant, mean protein intake at admission was higher than at time of discharge. Selected sub-optimal biochemical values were prevalent among the children studied, with 45% and 41% showing low serum albumin values «2.9g/dL) at the time of admission and at discharge respectively. Both on admission and at discharge, 38% of the children had Haemoglobin levels below normal values. Serum ferritin levels below normal values were present in almost all the children and the trend was similar for the prevalence of low zinc values. Sub-normal plasma retinol was present in 79% of the children at time of admission, while only 21% had deficient values at time of discharge (p=O.03). On admission, 29% of the children had vitamin evalues below the normal range whereas at time of discharge 17% of the children had values below normal (p=O.04). A total of 29% children presented with oral complications on admission. These included oral herpes, oral thrush, reflux, bleeding gums and stomatitis/angular cheilosis. Two children were asymptomatically colonized with Candida of the oral cavity. Mean total protein intake was higher (p=O.057) among the children who were not diagnosed with oral complications. Conclusions: This study confirmed that malnutrition is not only a common and serious problem associated with HIVand AIDS, but also that nutritional problems cannot be dealt with in isolation where Opportunistic Infections are present. The severity of malnutrition depends on various factors including oral complications. Additionally, appropriate management and treatment of tuberculosis did not appear to affect the nutritional status significantly. Recommendations: On the basis of these findings, and because of the increased risk of growth failure and developmental delays, children should be referred for full nutritional evaluation as soon as possible after diagnosis of HIV -infection. In addition, there is a need for intervention programmes to identify the immediate underlying causes of malnutrition and the ways in which such causes interact, in order to ensure that such interventions increase the resistance of HIV infected infants and children to the disease. / AFRIKAANSE OPSOMMING: Probleemdefiniëring: Binne die konteks van MIVNIGS is wanvoeding bykans universeelonder kinders en van die nadelige effekte van proteïen energie wanvoeding is die voorkoms van opportunistiese infeksies (Ol) met mikro-organismes soos orale candida die algemeenste. Doelwit: Die doel van dié studie was om die voedingstatus van kinders met orale komplikasies in verhouding tot MIVNIGS en die effek van orale letsels op voedingstatus, te bepaal. Proefpersone/omgewing: 'n Groep van 24 kinders, met beide tuberkulose en MIVNIGSinfeksie, wat agtereenvolgend in die kindersaal van Brooklyn Bors-Hospitaal in Kaapstad, Suid- Afrika opgeneem is, is bestudeer. Vir 'n periode van ses maande is die kinders se voedingstatus geassesseer deur middel van voedingstofinname, antropometriese status en biochemiese parameters met opname in en ontslag uit die hospitaal. Kliniese en orale ondersoeke was op elke kind uitgevoer met opname sowel as ontslag. Resultate: Kindres met HIV en tuberkulose, met of sonder orale letsels, het soortgelyke wanvoeding tydens hospitalisering ervaar het. Volgens antropometriese metings was daar geen verbetering in die voedingstatus nie. 'n Kombinasie van belemmerde groei, ondergewig en uittering het in 7% van die kinders tydens hospitalisering voorgekom. Nie een van die gemiddeldes van die voedingstowwe was hoër as die Aanbevole daaglikse toelatings (ADT) in enige van die kinders wat bestudeer is nie. Met opname sowel as ontslag, was koolhidraatinname die grootste energieverskaffer met onderskeidelik 36% en 42% (alhoewel die verskil nie statisties beduidend was nie). Daar was 'n beduidende toename in energie-inname (p=O.04) en 'n afname in totale vetinname (p=O.03) met ontslag. Alhoewel nie beduidend nie, was die gemiddelde proteïeninname hoër met ontslag. Die voorkoms van geselekteerde sub-optimale biochemiese waardes met toelating en ontslag wys dat onderskeidelik 45% en 41% van die kinders lae serum albumienwaardes «2.9g/dL) getoon het. Subnormale plasma retinol het in 79% van die kinders met toelating voorgekom, terwyl slegs 21% gebrekkige waardes (p=O.03) met ontslag getoon het. Tydens opname, sowel as met ontslag, was 38% van die kinders se hemoglobienvlakke laer as die normale. Serum ferritienvlakke was amper by al die kinders laer as die normale vlakke te bespeur, met sinkvlakke wat op soortgelyke lae vlakke voorkom. Met toelating was 29% van die kinders se Vitamien C-waardes laer as normaal en met ontslag was sowat 17% se waardes steeds laer as die normaal (p=O.04). Met toelating het 29% van die kinders orale komplikasies getoon. Ingeslote hierby was orale herpes, orale sproei, refluks, bloeiende tandvleise en stomatis/ angulêre cheilose. Slegs twee kinders was asimptomaties met orale Candida van die mondholte gediagnoseer. Die gemiddelde proteïeninname was hoër (p=O.057) onder die kindres wat nie orale komplikasies getoon het nie. Gevolgtrekking: Hierdie studie bevestig dat wanvoeding me net 'n algemene en ernstige probleem is wat met MIV en VIGS geassosieer word nie, maar ook in die teenwoordigheid van opportunistiese infeksies, die voedingsprobleem nie in isolasie gehanteer kan word nie. Die graad van wanvoeding hang af van ander faktore, insluitende orale komplikasies. Voldoende behandeling van TB het ook nie 'n beduidende effek op voedingstatus gehad nie. Aanbevelings: Op hierdie bevindings gebaseer, en as gevolg van die verhoogde risiko VIr belemmerde groei en vertraagde ontwikkeling wat al die liggaamstelsels van MIV -positiewe kinders affekteer, moet kinders so gou as moontlik nadat die MIV-infeksie gediagnoseer is, vir volle voedingsevaluasies verwys word. Daarmee gepaardgaande is daar 'n behoefte aan programme wat die onmiddellike onderliggende oorsake van wanvoeding identifiseer, asook om interaksie van hierdie oorsake met HIV vas te stel, ten einde intervensies wat weerstand van HIVkinders en-babas verbeter, positieftoe te pas.
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Determinants of excellent and poor adherence to antiretroviral therapy in Barberton

Chikoka, Tariro 10 1900 (has links)
Background: South Africa has a generalised HIV epidemic which is managed through free Antiretroviral Therapy (ART). Adherence to ART has emerged as a crucial issue in HIV/AIDS therapeutics. Purpose: The aim of the study was to explore determining factors for poor and excellent adherence to ART for HIV positive patients residing in Barberton, a mining town in Mpumalanga Province. Methodology: A generic qualitative research design was undertaken. Data was collected through in-depth qualitative interviews from a purposive sample of 13 ART patients. Qualitative interpretive analysis was employed. Findings: The study found that excellent adherence to ART is significantly associated with the availability, effectiveness and comprehensiveness of HIV services, psychological support and medical advances. Side effects of ART, opportunistic infections and alcohol and drug use hinder adherence. However, longer duration on ART enhanced self-efficacy and facilitated adherence. Successful ART is dependent on taking ARVs as prescribed and executing necessary lifestyle changes. / Health Studies / M.P.H.

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