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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.
411

Factors influencing adherence to antiretroviral therapy in adolescents at Botswana-Baylor Children's Clinical Centre of Excellence : a qualitative study

Marukutira, Tafireyi 11 1900 (has links)
The aim of the study was to determine the factors that influence adherence to ART among adolescents who contracted HIV through vertical transmission. Qualitative research using descriptive phenomenology was conducted at Botswana-Baylor Children’s Clinical Centre of Excellence. Data was collected using in-depth individual semi-structured interviews. Eight (8) adolescents between 14 and 19 years who had been on ART for minimum of 4 years were interviewed. Thematic analysis of data was done and five (5) themes emerged from the participants' description of the experience of taking ART over a long period of time. The themes that emerged indicated the factors that influence adherence to ART, and they included knowledge and positive beliefs about ART, need for support, ART difficult treatment regimen, having a regular doctor and psychosocial emotional needs. The findings suggested that the adolescents who contracted HIV through vertical transmission require support while continuing on a simplified long-term ART regimen after an assessment of their psychological well beings and periodic checks. / Health Studies / M.A. (Public Health)
412

A comparison of the effectiveness of protease inhibitor-based highly active anti-retroviral treatment regiments in Trinidad and Tobago

Ziregbe, Elohor 21 October 2014 (has links)
Few studies have assessed the optimum second line highly active anti-retroviral therapy (HAART) regimen in patients who had failed on the first-line HAART in resource-limited settings. This study aimed to compare the Protease inhibitor (PI)-based second line HAART regimens used in one clinic in Trinidad by comparing immunological, virological and clinical outcomes of patients on the different second line HAART regimens. The records of 35 treatment-experienced patients, over 21years of age and on PI-based regimens for at least six months, were analysed using SPSS version 20. The regimen containing TDF/FTC/AZT/LPV/r proved to produce superior outcomes compared to the other second line regimens. Due the small number of usable patients’ records, the findings cannot be generalised but indicate directions for future studies attempting to compare the treatment outcomes of different second line HAART regimens / Health Studies / M. A. (Public Health)
413

Antiretroviral adherence and HIV virological outcomes in HIV-positive patients in Ugu District, KwaZulu-Natal Province

Kapiamba, Muteba Germain 24 July 2015 (has links)
Adherence to antiretroviral therapy is crucial to ensure viral suppression. In the scientific community it is widely accepted that an adherence level of at least 90% is necessary to achieve viral suppression. This study uses pharmacy refill records to describe antiretroviral adherence in HIV-positive patients in Ugu District and to describe pharmacy refill records as reliable monitoring method of antiretroviral therapy. In total, 61 patients’ records were reviewed. Overall, 82% of participants (n=50) achieved an optimum adherence level of at least 90%. Although 38% (n=19) of these participants did not show any related viral suppression. A statistically significant relationship between adherence and viral suppression was not demonstrated. Therefore, pharmacy refill records cannot be recommended as an alternative method of monitoring response to antiretroviral therapy, but laboratory tests including CD4 cell count and or viral load must be combined to pharmacy refill method for monitoring of antiretroviral therapy in HIV-positive patients / Health Studies / M.A. (Public Health)
414

Factors associated with delayed entry into HIV medical care among HIV positive people who are aware of their status in Bulawayo Zimbabwe

Makasi, Tasara 02 1900 (has links)
Using non-experimental descriptive exploratory survey, this study sought to find out factors associated with delayed entry into HIV medical care among HIV positive people who are aware of their status. A quantitative design was used and a structured questionnaire was used as the data collection instrument. Respondents were patients in a hospital’s Opportunistic Infection Department whose hospital records indicated that they were HIV positive during the time of the study. The study found out that as much as 71.6% (n =43) first entered HIV medical care more than 12 months after testing HIV positive while 40% (n = 24) did so as a result of illness. Low education levels, unemployment and being single are associated with delayed entry into HIV medical care. A percentage of the population uses and trusts non-biomedical approaches to dealing with HIV/AIDS. Being diagnosed HIV positive is therefore not necessarily a strong reason enough for one to immediately enter into medical care. Intensive health education needs to be done at work places, health facilities, schools, through print and electronic media, churches and other community settings to equip the population with knowledge of the advantages of early entry into HIV care. / Health Studies / M.A. (Public Health)
415

The impact of Isoniazid Preventive Therapy (IPT) on tuberculosis incidence among HIV infected patients in Addis Ababa, Ethiopia

Sade, Anteneh Habtenarian, Anteneh Habtemariam Sade 24 October 2013 (has links)
Background: IPT is an effective, safe and feasible disease prevention scheme that should be administered for all PLHIV living in areas with high latent TB prevalence. Objective: To assess the impact of isoniazid in the incidence of tuberculosis among HIV infected individuals in Addis Ababa. Methods: A case control study design was undertaken among 489 HIV and TB infected patients in Addis Ababa from January 2008 to December 2010. Results: Tuberculosis incidence rate among those who developed TB after completing 6-9 month isoniazid preventative therapy was17.14 PYO compared to 10.28 PYO among those who were not. Isonizide reduced the chance of developing tuberculosis among HIV infected patients (OR= 0.072; 95% CI 0.044, 0.12). Age (AOR= 0.14; 95% CI 0.03, 0.97) and sex (AOR= 1.86; 95% CI 1.02, 2.23) of the patient, CD4 count at HIV diagnosis (AOR= 0.21; 95% CI 0.13, 0.31), clinical stage of HIV illness (AOR= 1.22; 95% CI 1.09, 1.84) and past tuberculosis history (AOR = 1.97; 95% CI 1.24, 3.67) were major factors associated with tuberculosis incidence. Conclusions: INH prophylaxis was associated with lower incidence of tuberculosis among PLHIV. / Health Studies / M. Public Health
416

Treatment through empowerment? : exploring the dynamics of ‘responsibility’ in antiretroviral therapy (ART) in two clinics in the Cape Winelands

Myburgh, Hanlie 03 1900 (has links)
Thesis (MA)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This study investigates how the new technology of treatment, i.e. antiretroviral therapy (ART), is incorporated into public health care institutions. The success of this technology ideally relies on the notion of the ‘responsibilised’ patient as one who, simply put, consistently maintains the level of ARV-adherence necessary to suppress the viral load and to avoid drug resistance. The stringent management and continual monitoring of treatment adherence necessary to achieve these outcomes lie beyond the direct control of the health care institution. Given that the institution sees its patients irregularly, a patient’s divergence from treatment guidelines is established only after the fact. The institution takes on a supporting role while it is the patient who, on a day-to-day, dose-by-dose basis manages and monitors themselves, making ART a seemingly individual endeavour and responsibility. This shift in responsibility is compatible with the ‘new contract’ between provider and client, necessitated by ART. Even so, the institution attempts to manipulate the day-to-day behaviours of the patient to conform to those required in order to achieve treatment outcomes. This thesis examines how these different aspects of ART play out within two clinics in the Cape Winelands, and more specifically, the institutional intricacies of managing a disease which requires treatment that is not directly observed. / AFRIKAANSE OPSOMMING: Die studie ondersoek hoe die nuwe tegnologie van behandeling, antiretrovirale behandeling (ARB), in publieke gesondheidsorgklinieke geïntegreer word. Die sukses van hierdie tegnologie hang af van die nosie van die ‘verantwoordelike’ pasiënt wat, eenvoudig gestel, die nodige vlak ARV-gebruik handhaaf om die virale lading te onderdruk en weerstand te voorkom. Die streng kontrole oor die toewyding tot behandeling wat nodig is om hierdie uitkomstes te bereik, lê buite die direkte beheer van die gesondheidsorgkliniek. Aangesien die kliniek sy pasiënte slegs periodiek sien, word ʼn pasiënt se afwyking van behandelingsriglyne eers later gemeet. In hierdie opsig neem die kliniek 'n ondersteunende rol in, terwyl dit die pasiënte is wat op 'n daaglikse, dosis-tot-dosis basis hulself moet handhaaf en monitor. Dit maak ARB 'n oënskynlike individuele onderneming en verantwoordelikheid. Hierdie skuif in verantwoordelikheid is in lyn met die nuwe kontrak tussen die gesondheidsorgdiens en die kliënt, wat deur ARB genoodsaak word. In ieder geval probeer die institusie om die daaglikse gedrag van die pasiënt te manipuleer om te pas by die riglyne wat deur die uitkomstes genoodsaak word. Hierdie tesis ondersoek hoe hierdie verskillende aspekte van ARB binne twee klinieke in die Kaapse Wynland uitspeel, en meer spesifiek, die institusionele bestuur van 'n siekte waarvoor behandeling nie direk geobserveer kan word nie.
417

Platelet flow cytometry and coagulation tests as markers of immune activation in chronic HIV infection

Nkambule, Bongani Brian 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / Bibliography / ENGLISH ABSTRACT: Background: In the era of antiretroviral therapy (ART), the risk of acquired immune deficiency syndrome (AIDS) related deaths has decreased and people living with Human Immunodeficiency Virus (HIV) now have prolonged life spans. However, an increasing trend of non-AIDS associated deaths has been reported despite adequate control of viral loads. HIV infection is established as a chronic inflammatory condition which is associated with an increased risk for thrombosis. Thus HIV infected patients are at a higher risk of developing cardiovascular disease (CVD) and other inflammatory-associated complications. Inflammation is linked with thrombosis and promotes the formation of thrombin, which plays an important role in platelet activation. Furthermore, activated platelets have been shown to play a key role during infection and the inflammatory process, particularly by mediating interactions between cells of innate immunity. Soluble markers of platelet activation have been shown to be increased in HIV-infection. However, these have not been well documented by flow cytometry. P-selectin CD62P is stored in the alpha granules of platelets and is expressed on the surface only upon platelet activation. This facilitates interaction with other blood cells and the endothelium. Activated platelets may play a role in HIV-induced atherosclerosis through the expression and release of mediators that induce endothelial activation and support the adhesion of leukocytes to the inflamed vessel wall. Fibrinogen is a precursor of the blood coagulatory protein fibrin and the degradation of fibrin to D-dimer is a measure of the formation and the subsequent dissolution of blood clots. In HIV infected patients, chronic inflammation induces the up-regulated expression of tissue factor (TF) on monocytes which triggers the activation of the clotting cascade and increases the level of D-dimers. Methods: This pilot study consisted of ART naïve patients and all platelet flow analyses were carried out on whole blood. In this study, a total of 57 adult South Africans were recruited from a clinic in the Western Cape. These included 32 HIV positive patients and 25 HIV negative individuals. The levels of platelet activation and platelet function were investigated using a novel platelet cytometry assay. The method was optimized to ensure minimal platelet activation: no centrifugation or red blood cell (RBC) lysis steps were performed. The platelet-specific markers CD41a and CD42b were used to ensure gating on platelets only. CD62P expression was used to evaluate platelet activation and these levels were correlated with Fibrinogen, hsCRP, Ddimer, CD4 counts and viral load. Furthermore, platelet function was evaluated by investigating the response of platelets to endogenous agonists which included adenosine diphosphate(ADP) and arachidonic acid (AA) at varying concentrations. Results:This study demonstrated higher baseline levels of CD62P expression in treatment naïve HIV positive patients as compared to uninfected controls (mean %CD62P 71.74 ± 2.18 vs control 54.52 ± 2.42; p=<0.0001). In addition it was shown that %CD62P expression correlated directly with platelet counts (r=0.374, p=0.042). Platelet counts showed an inverse correlation with viral loads (give values) Fibrinogen levels correlated with the absolute WCC (r=0.659, p=0.0021); absolute neutrophil count (r=0.619, p=0.0105); absolute monocyte count (0.562, p=0.0235) and hsCRP (r=0.688 p=0.0011). In addition, fibrinogen showed a strong negative correlation with CD4 counts (r=-0.594, p=0.0014) and therefore, may be a valuable marker of both disease progression and risk of thrombosis in treatment naïve HIV positive patients. HsCRP levels correlated with the absolute neutrophil counts (r=0.392, p=0.0005). The HIV Group showed an overall hyper-response to ADP at a concentration 0.025 μM as compared to uninfected controls (62.34 ± 9.7 vs control 36.90 ± 5.7, p=0.0433). Conclusions: In this study we describe a novel Flow Cytometry technique that may be used to evaluate the levels of platelet activation and platelet function in HIV infected patients. In addition we report a cost-effective panel in the form of fibrinogen, WCC and platelets that may be valuable in predicting the progression of HIV infection to AIDS or other inflammatory- associated complications in treatment naïve HIV infected patients. Platelet counts showed an inverse correlation with viral loads and a direct correlation with the level of activated platelets. These findings taken together suggest the potential prognostic value of platelet activation and platelet counts in the context of asymptomatic HIV infected patients. Our findings suggest WCC and Fibrinogen may be used to evaluate the inflammatory profile of individual HIV infected patients. This may have a direct impact on HIV patient management prior to initiation of antiretroviral therapy and valuable in monitoring responses to treatment. Further, we present a novel flow cytometry based platelet functional assay and suggest the use of ADP at a concentration of 0.025 μM to evaluate platelet function optimally in HIV infected patients. The utilization of the novel Flow Cytometry technique as described in this study would add significant value in the assessment of thrombotic risk and disease progression in HIV infected patients and may additionally prove to be of value in other chronic inflammatory conditions. / AFRIKAANSE OPSOMMING: Voorkennis: In die era van antiretrovirale terapie (ART), het die risiko van vigs-verwante sterftes verminder en mense wat nou met volle naam (MIV) leef, het ‘n verlengde lewensduur. Nogtans, word 'n toenemende neiging van nie-vigs geassosieer sterftes berig wat hoofsaaklik toegeskryf word aan trombotiese toestande. MIV-infeksie word as 'n chroniese inflammatoriese toestand beskou met ʼn verhoogde trombose risiko geassosieer word. Dus, MIV-besmette pasiënte het 'n hoër risiko om kardiovaskulêre siekte (CVD) te ontwikkel ongeag of hulle ARV naïef is of op behandeling is nie. Inflammasie word geassosieer met trombose en bevorder die vorming van trombien, wat 'n belangrike rol in plaatjie aktivering speel. Verder, word daar bewys dat geaktiveerde bloedplaatjies 'n belangrike rol speel tydens infeksie en die inflammatoriese proses.Hulle bemiddel interaksies tussen die selle van ingebore immuniteit. Daar word bewys dat oplosbare merkers van plaatjie aktivering verhoog is in MIV-infeksie, maar die bewyse is nie so goed gedokumenteer deur vloeisitometrie nie. P-selectin (CD62P) word gestoor in die alfa korrels van plaatjies en word uitgedruk op die oppervlak slegs wanneer plaatjies geaktivering word; daardeur fasilitering dit die interaksie met ander bloedselle en die endoteel. Geaktiveerde plaatjies kan ook 'n rol in MIV-geïnduseerde aterosklerose speel deur middel van die uitdrukking en vrylating van bemiddelaars wat endoteel aktivering induseer asook die adhesie van leukosiete aan die ontsteekte vat wand ondersteun.. Fibrinogeen, 'n voorloper van die bloed koagulatories proteïen fibrin en die degradasie van fibrin na D-dimeer is' n maatstaf van die vorming en die daaropvolgende ontbinding van bloedklonte. Kroniese inflammasie in MIVbesmette pasiënte, induseer die op-gereguleerde uitdrukking van weefsel faktor (TF) op monosiete wat die aktivering van die stolling kaskade inisieer en die D-dimere vlakke verhoog. Metodes: Hierdie loodsstudie bestaan uit ART naïewe pasiënte en al die plaatjie vloei ontleding was op vol bloed uitgevoer. In hierdie studie, 'n totaal van 57 volwasse Suid-Afrikaners was van' n kliniek in die Wes-Kaap gewerf. Dit sluit 32 MIV-positiewe pasiënte en 25 MIV negatiewe individue in. Die vlakke van plaatjie aktivering en plaatjie funksie was ge ondersoek deur middel van 'n nuwe plaatjie sitometrie toets. Die metode was geoptimaliseer om minimale plaatjie aktivering te verseker: dus geen sentrifugering of volle naam (RBS) liseer stappe was gebruik nie. Die plaatjie-spesifieke merkers, CD41a en CD42b was gebruik om te verseker dat slegs bloedplaatjes gekies word. Die uitdrukking van CD62P was gebruik vir die evaluering van plaatjie aktivering en hierdie vlakke was gekorreleer met fibrinogeen, hsCRP, D-dimeer, CD4- tellings en virale lading. Verder, was plaatjie funksie geëvalueer deur die reaksie van plaatjies aan endogene agoniste wat ADP en AA by wisselende konsentrasies insluit te ondersoek. Results: Hierdie studie het getoon hoër basislyn vlakke van CD62P uitdrukking in behandeling naïewe MIV-positiewe pasiënte in vergelyking met onbesmette beheermaatreëls (beteken% CD62P 71,74 ± 2,18 vs beheer 54,52 ± 2,42, p <0.0001). Daar is ook getoon dat% CD62P uitdrukking direk gekorreleer met plaatjie tellings (r = 0,374, p = 0,042). Plaatjie tellings het 'n omgekeerde korrelasie met virale ladings (gee waardes) fibrinogeen vlakke korreleer met die absolute WCC (r = 0,659, p = 0,0021), absolute neutrofiel telling (r = 0,619, p = 0,0105); absolute monosiet telling (0,562, p = 0,0235) en hsCRP (r = 0,688 p = 0,0011). Daarbenewens, fibrinogeen het 'n sterk negatiewe korrelasie met 'n CD4-tellings (r = -0,594, p = 0,0014) en daarom kan 'n waardevolle merker van beide die siekte en die risiko van trombose in behandeling naïewe MIV-positiewe pasiënte. HsCRP vlakke gekorreleer met die absolute neutrofiel tellings (r = 0,392, p = 0,0005). Die MIV-groep het 'n algehele hiper-reaksie op die ADP by 'n konsentrasie 0,025 μM in vergelyking met onbesmette beheermaatreëls (62,34 ± 9,7 vs beheer 36,90 ± 5.7, p = 0,0433). Gevolgtrekkings: In hierdie studie beskryf ons 'n roman vloeisitometrie tegniek wat gebruik kan word om die vlakke van Plaatjie aktivering en plaatjie funksie in die MIV-besmette pasiënte te evalueer. Verder het ons 'n verslag van 'n koste-effektiewe paneel in die vorm van fibrinogeen, WCC en plaatjies wat waardevol kan wees in die voorspelling van die vordering van MIVinfeksie tot VIGS of ander inflammatoriese-verwante komplikasies in die behandeling naïewe MIV-besmette pasiënte. Plaatjie tellings het 'n omgekeerde korrelasie met die virale laste en 'n direkte verband met die vlak van geaktiveerde bloedplaatjies. Hierdie bevindinge saam, dui op die moontlike prognostiese waarde van Plaatjie aktivering en die plaatjie tel in die konteks van die asimptomatiese MIV-geïnfekteerde pasiënte. Ons bevindinge dui daarop WCC en fibrinogeen kan gebruik word om die inflammatoriese profiel van individuele MIV-geïnfekteerde pasiënte te evalueer. Dit kan 'n direkte impak op MIV pasiënt vooraf aan die inisiasie van antiretrovirale terapie en waardevolle in die monitering van die reaksie op behandeling. Verder bied ons 'n roman vloeisitometrie gebaseer plaatjie funksionele toets en dui op die gebruik van die ADP teen 'n konsentrasie van 0,025 μM plaatjie funksie optimaal te evalueer in MIVgeïnfekteerde pasiënte. Die benutting van die roman vloeisitometrie tegniek soos beskryf in hierdie studie sal 'n beduidende waarde toevoeg in die beoordeling van die die trombotiese risiko en die siekte in MIV-geïnfekteerde pasiënte en kan addisioneel bewys van waarde te wees in 'n ander chroniese inflammatoriese toestande. / National Reserach Foundation
418

Impact des traitements antirétroviraux sur le risque de transmission sexuelle du VIH en Afrique Subsaharienne : le cas du Cameroun

Ndziessi, Gilbert 03 April 2013 (has links)
Approfondir les connaissances sur l'évolution et les facteurs associés aux comportements sexuels chez les PVVIH exposées aux traitements antirétroviraux en Afrique subsaharienne. Données collectées dans le cadre d'un essai randomisé conduit dans neuf hôpitaux de district ruraux au Cameroun. 459 PVVIH éligibles au traitement inclus et suivis sur 24 mois. Régression logistique à effets mixtes utilisée pour analyser les facteurs associés aux différentes variables réponses étudiées.La proportion des patients sexuellement actifs augmente de 32% à l'inclusion à 56% après 24 mois de traitement. Une augmentation supplémentaire du temps depuis l'initiation du traitement de 6 mois augmente de 30% de la probabilité de déclarer une activité sexuelle sous ARV. Proportion des patients ayant des comportements sexuels à risque (CSR) baisse significativement de 76% à l'inclusion à 66% au 24e mois, les patients obervants au traitement étaient moins susceptibles de rapporter les CSR. La proportion des patients susceptibles de transmettre le VIH par voie sexuelle (STVIH) baisse de 76% à l'inclusion à 27% après 24 mois de traitement ARV. Une augmentation du temps depuis l'initiation du traitement de 6 mois réduit de 66% la STVIH. Mes travaux montrent un impact positif des ARV sur l'activité sexuelle des PVVIH, les CSR et la STVIH, suggérant un effet positif de l'exposition des PVVIH aux traitements ARV sur la prévention de la transmission sexuelle du VIH. Mais, le risque potentiel de transmission du VIH persiste nécessitant le renforcement des interventions de réduction des risques dans les programmes d'accès aux ARV. / To evaluate the evolution and factors associated with sexual behavior among PLWHA exposed to antiretroviral therapy in sub-Saharan Africa. Data collected as part of a randomized trial conducted in nine rural district hospitals in Cameroon. 459 PLWHA eligible for treatment included and followed for 24 months. Mixed effects logistic regression used to analyze factors associated with different response variables studied. Proportion of patients sexually active increased from 32% at baseline to 56% after 24 months of treatment. An additional 6 months increase of the time since initiation of treatment increase in 30% the probability of reporting sexual activity. Proportion of patients with sexual risk behavior (SRB) decreased significantly from 76% at baseline to 66% at 24 months and patient obervants to treatment were less likely to report CSR. Proportion of patients likely to transmit HIV through sexual intercourse (STVIH) decrease from 76% at baseline to 27% after 24 months of HAART. Analyses shown that increasing in 6 months of time since initiation of treatment reduced STVIH by 66%. My dissertation show a positive impact of ART on sexual activity, CSR and STVIH among PLWHA, suggesting a positive effect of exposure to HAART on the prevention of sexual transmission of HIV. However, the potential risk of transmission of HIV persists requiring strengthening risk reduction interventions in HAART access programs.
419

Avaliação da resposta tecidual \"in situ\" do fenótipo, da expressão de HHV-8/LANA e de citocinas em lesões cutâneas de sarcoma de Kaposi clássico e sarcoma de Kaposi associado à AIDS na era pré e pós-terapia anti-retroviral combinada / Evaluation of tissue response \"in situ\" of the phenotype, expression of HHV-8/LANA and cytokines in cutaneous lesions of classic Kaposi sarcoma and AIDS associated Kaposi sarcoma in the pre-and post- highly active antiretroviral therapy era

Luiz, Fernanda Guedes 15 December 2008 (has links)
Sarcoma de Kaposi (SK) é um tumor de origem vascular associado ao herpesvírus 8 humano (HHV-8). A incidência do SK-AIDS tem diminuído após o advento da terapia anti-retroviral combinada (HAART), sem estudos relacionando a resposta inflamatória cutânea e a expressão de HHV-8 na era pré e pós HAART. Utilizamos a immuno-histoquímica para caracterizar e quantificar in situ as células inflamatórias, o padrão de citocinas e a expressão de HHV-8 em lesões cutâneas de sarcoma de Kaposi clássico (SKC), sarcoma de Kaposi associado à AIDS (com ou sem HAART). O número diminuído de linfócitos TCD4+ em lesões de SK-AIDS quando comparado com SKC, reflete a imunodeficiência severa causada pelo HIV. O número de linfócitos TCD8+ foi similar nos três grupos de SK, o qual parece não se correlacionar com a forma clínico-epidemiológica do SK. As células S100+ e DD FXIIIa+ estiveram aumentadas em todas as lesões de SK comparadas com a pele normal. Nós também encontramos uma população celular dérmica S100+CD1a- peculiar nas lesões de SK. Os macrófagos CD68+ estiveram aumentados nas lesões de SKC quando comparados com as lesões de SK-AIDS, mas similares com aqueles encontrados em lesões de SK-AIDS/HAART. Dados semelhantes foram encontrados nas células de Langerhans epidérmicas nesses grupos, sugerindo uma recuperação immune parcial através da HAART. O número aumentado de células expressando IFN- em lesões de SKC e SK-AIDS/HAART quando comparado com SK-AIDS sugere essa citocina como um indicador de resposta imune mais eficaz. A expressão aumentada de IL-1 nas lesões de SKC e SK-AIDS/HAART poderia estar relacionada ao seu efeito anti-tumoral. A expressão de TNF-, IL-4 e IL-6 foram similares entre as lesões de SK avaliadas. Através de dupla marcação, a identificação nuclear de HHV-8 em DD FXIIIa+ sugere esse tipo celular como alvo para infecção por HHV-8. As lesões de SKC apresentaram número aumentado de células com expressão de HHV-8 quando comparado com os grupos de SK-AIDS, independente da HAART. Nosso estudo mostra que existiu uma recuperação da resposta immune local nas lesões de SK-AIDS/HAART e que a severidade clínica do SK não pode estar diretamente associada com a densidade aumentada de células infectadas pelo HHV-8 no tecido / Kaposis sarcoma (KS) is a vascular-originated tumor associated to human herpesvirus 8 (HHV-8). The incidence of AIDS-KS has decreased after the advent of highly active antiretroviral therapy (HAART), without studies regarding cutaneous inflammatory response and HHV-8 expression in pre- and post-HAART era. We used immunohistochemistry to characterize and to quantify in situ inflammatory cells, its cytokines pattern and the expression of HHV-8 in cutaneous lesions of classic Kaposis sarcoma (CKS), AIDS associated Kaposis sarcoma (with or without HAART). The decreased number of T CD4+ lymphocytes in lesions of AIDS-KS as compared with CKS, reflect the severe immunodeficiency caused by HIV. T CD8+ lymphocytes numbers were similar in three KS groups, which appeared unrelated to the clinical or epidemiological type of KS. S100+ cells and FXIIIa+ DD were increased in all KS lesions as compared with normal skin. We also found a peculiar dermal cellular population in KS lesions. CD68+ macrophages were higher in CKS lesions as compared with AIDS-KS lesions, but similar to those found in lesions of HAART/AIDS-KS. Similar data were found in epidermal Langerhans cells in these groups, suggesting a partial immune recovery by HAART. The high number of cells expressing IFN- in CKS lesions and HAART/AIDS-KS as compared with AIDS-KS suggests that this cytokine may be a marker of effective immune response. The increased expression of IL-1 in CKS lesions and HAART/AIDS-KS could be related with its anti-tumor effect. Expression of TNF-, IL-4 e IL-6 were similar between KS lesions. Demonstrated by double-immunostaining, nuclear identification of HHV-8 in FXIIIa+ DD suggests this cell type as target for HHV-8 infection. CKS lesions showed increased number of cells with HHV-8 expression as compared with another groups of AIDS-KS, independent of HAART. Our data shown that there was a partial recovery of local immune response in HAART/AIDS-KS lesions and that the KS clinical severity cannot be directly associated with the increased density of HHV-8 infected cells in tissue
420

Detecção do vírus de Epstein-Barr (EBV), expressão de FOXP3 e avaliação da carga viral para EBV como marcadores prognósticos nos linfomas relacionados à AIDS / Epstein-Barr virus (EBV) detection, FOXP3 expression and evaluation of EBV viral load as prognostic markers in Aids-related lymphomas

Tanaka, Paula Yurie 24 September 2012 (has links)
Introdução: Pacientes com infecção pelo HIV têm risco aumentado para o desenvolvimento de linfomas não-Hodgkin de células B comparado à população geral. Dentre os mecanismos que podem estar relacionados a esta patologia, encontra-se a reativação do vírus de Epstein-Barr secundária a imunossupressão. O papel do sistema imune para desenvolvimento de tumores é citado há longa data, e seu equilíbrio é mantido pelos linfócitos T regulatórios, cujo principal regulador e marcador é o fator de transcrição FOXP3. Neste estudo, avaliamos a presença de EBER e FOXP3 em amostras diagnósticas, além da carga viral para o vírus de Epstein-Barr em pacientes com linfomas relacionados à Aids a fim de avaliar e correlacionar os resultados como marcadores prognósticos nesta população. Métodos: Análise prospectiva da carga viral para Epstein-Barr no plasma e em células mononucleares do sangue periférico em 15 pacientes com linfomas relacionados à Aids acompanhados no Serviço de Hematologia do Instituto de Infectologia Emílio Ribas e do Hospital das Clínicas/Instituto do Câncer do Estado de São Paulo da Faculdade de Medicina da Universidade de São Paulo. As mensurações foram realizadas para cada paciente por reação da cadeia de polimerase em tempo real ao diagnóstico, término do tratamento e três meses após o término do tratamento. Dois grupos controles constituídos de 26 pacientes infectados pelo HIV em uso de anti-retroviral e sem diagnóstico de linfoma ou infecção oportunista e 30 indivíduos saudáveis também foram analisados para comparação da carga viral para o vírus de Epstein-Barr. Amostras coletadas por biópsia para o diagnóstico de linfoma foram submetidas a análise imuno-histoquímica para FOXP3 e para EBER por hibridização in situ. Resultados: 13 pacientes eram do sexo masculino e dois do sexo feminino, dos quais 14 foram tratados com quimioterapia e um com radioterapia de sistema nervoso central. Nove de 15 pacientes (60%) completaram o tratamento proposto e obtiveram remissão completa. A mediana da carga viral para o vírus de Epstein-Barr antes do tratamento foi 13 cópias/106 nas células mononucleares do sangue periférico (1-1472 cópias/106) e 70 cópias/mL (0-24900 cópias/mL) no plasma. Após o tratamento foi de 0,5/106 (0-109,5) e indetectável no plasma, com diminuição significativa da carga viral em células mononucleares do sangue periférico (p=0,022) e no plasma (p=0,003) ao término do tratamento em comparação ao diagnóstico. Nos pacientes em remissão completa, a carga viral para o vírus de Epstein-Barr diminuiu tanto no plasma como em células mononucleares do sangue periférico na maioria dos casos. A hibridização in situ para EBER resultou positiva em 7/15 (46,7%) casos, sendo significativamente superior no grupo de pacientes com linfomas relacionados a AIDS com mais de um sítio extralinfonodal comprometido (p=0,041) e com linfócitos T CD4 <100 células/L (p=0,026). A expressão de FOXP3 foi negativa em 15/15 (100%) dos pacientes com ARL. Conclusões: A expressão de EBER foi positiva em 7/15 (46,7%) dos pacientes com linfomas relacionados à Aids e superior de forma significativa nos pacientes com estádio mais avançado do linfoma e maior grau de imunossupressão. Observou-se diminuição estatisticamente significativa da mediana de carga viral para o vírus de Epstein-Barr em células mononucleares do sangue periférico (p=0,022) e plasma (p=0,003) após o tratamento do linfoma em comparação aos valores do diagnóstico em pacientes que atingiram remissão completa, o que poderia ser considerado um marcador prognóstico de resposta a terapia / Introduction: Patients with HIV infection have increased risk for development of non-Hodgkins lymphoma compared to general population. Among mechanisms that could be related to this disease is the reactivation of Epstein-Barr virus infection secondary to immunosuppression. The role of immune system in development of tumors was reported a long time ago, and balance of this system is maintained by regulatory T cells; FOXP3 transcription factor is the main regulator and marker of these cells. In this study we evaluated the presence of EBER and FOXP3 in diagnostic samples, and also viral load of Epstein-Barr virus in patients with Aids-related lymphoma to evaluate and correlate the results as prognostic markers in this population. Methods: Prospective analysis of viral load of Epstein-Barr virus in plasma and peripheral blood mononuclear cells from 15 patients with Aids-related lymphoma treated at Instituto de Infectologia Emílio Ribas and Hospital das Clínicas/Instituto do Câncer do Estado de São Paulo da Faculdade de Medicina da Universidade de São Paulo. Viral load measures were performed by real time polymerase chain reaction at diagnosis of lymphoma, completion of treatment and three months afterwards. Two control groups composed by 26 HIV-positive patients in use of HAART and without diagnosis of lymphoma or opportunistic infection and 30 healthy persons were also analyzed for viral load comparison. Biopsy samples performed to lymphoma diagnosis were submitted to immunohistochemistry for FOXP3 and in situ hybridization to EBER. Results: 13 patients were male and two females, 14 were treated with chemotherapy and one with radiotherapy of central nervous system. Nine of 15 patients (60%) completed treatment achieving complete remission. Median viral load of Epstein-Barr virus before treatment was 13 copies/106 in peripheral blood mononuclear cells (1-1472 copies/106) and 70 copies/mL (0-24900 copies/mL) in plasma. After treatment it was 0,5/106 (0-109,5) and not detectable in plasma, with significant decrease of viral load in peripheral blood mononuclear cells (p=0,022) and in plasma (p=0,003) after treatment compared to diagnosis. In patients with complete remission, viral load decreased in the majority of cases. In situ hybridization for EBER was positive in 7/15 (46,7%), and significant higher in the group of patients with Aids-related lymphoma with more than one extra nodal site (p=0,041) and CD4 T-cells <100 cells/L (p=0,026). FOXP3 expression was negative in 15/15 (100%) of patients with ARL. Conclusions: EBER expression was positive in 7/15 (46,7%) of patients with Aids-related lymphoma and significantly higher in patients with advanced stages of lymphoma and higher degree of immunosuppression. Significant decrease in median viral load of Epstein-Barr virus was observed in peripheral blood mononuclear cells (p=0,022) and plasma (p=0,003) after lymphoma treatment compared to diagnosis in patients that achieved complete remission, what could be considered a prognostic marker of response to therapy

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