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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.
221

Expression and function of drug transporters in an in vitro model of the mammary epithelial barrier (BME-UV)

Al-Bataineh, Mohammad M. January 1900 (has links)
Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / Ronette Gehring / Milk composition has a dynamic nature, and the composition varies with stage of lactation, age, breed, nutrition and health status of the udder. The changes in milk composition seem to match the changes in the expression of membrane proteins in secretory mammary epithelial cells that are needed for the movement of molecules from blood to milk and vice versa (Nouws and Ziv, 1982). Thus, an understanding of transporter expression, function and regulation in mammary epithelial cells can provide insight into mammary gland function and regulation. The goal of this project was to elucidate (molecularly and functionally) the role of drug transporters in the barrier function of an epithelial monolayer cultured from an immortalized bovine mammary epithelial cell line (BME-UV). To characterize the regulation (expression and function) of these drug transporters in BME-UV cells after exposure to cytokine TNF-α for selected periods of time. Representative members of drug transporters of the SLC (OCT and OAT) and ABC (P-glycoprotein) superfamilies were chosen for this project. In the first study, the involvement of a carrier-mediated transport system in the passage of organic cation (TEA) and anion (EsS) compounds was elucidated across the BME-UV monolayer. In the second study, molecular and functional expression of bOAT isoforms in BME-UV cells were studied. The final study characterized the effects of cytokine TNF-α on the expression and function of P-glycoprotein, an efflux pump, in BME-UV cells. Cytokine TNF-α exposure induced the expression of ABCB1 mRNA and increased P-glycoprotein production in BME-UV cells, resulting in a greater efflux of digoxin, a known P-glycoprotein substrate, back into the apical fluid. The expression, function, and regulation of these transporters in the mammary gland has important implications for understanding the barrier function of the mammary epithelium and, in more specific, for characterizing the role of these transporters in the accumulation and/or removal of specific substrates from milk and/or plasma. Moreover, this study provides an in vitro cell culture model of mammary epithelium to characterize mammary epithelial cell function during inflammation.
222

Signalling mechanisms involved in TNF-α mediated cytoprotection during ischaemic injury in a C2C12 muscle cell line

Loos, Benjamin January 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Both, the cytokine Tumor Necrosis Factor-α (TNF-α) and the enzyme cytosolic phospholipase A2 (cPLA2) are crucial driving forces in mediating the cellular inflammatory response and are involved in ischaemic injury. During an ischaemic insult, TNF-α is endogenously generated. Apart from the recognized effects of TNF- α, such as the induction of apoptosis, proliferation and differentiation, if present in low dosages, it also mediates cytoprotective effects. Upon activation, cPLA2 contributes to the ischaemic challenge with the generation of mediators of cellular injury and apoptosis. Upon stimulation, this calcium dependent enzyme translocates to the phospholipid compartment of the cell membrane and induces the hydrolysis of sn-2 ester bonds in phospholipids. It governs the release of free fatty acids and lysophospholipids and generates role players of inflammation. We suggest a role for cPLA2 in the TNF-α mediated cytoprotection, with a distinct phosphorylation and translocation pattern. Aims The involvement of cPLA2 in TNF-α mediated cytoprotection in the C2C12 murine skeletal muscle cell line in tolerance to ischaemia was examined. To investigate the nature of the cPLA2 phosphorylation pattern, the mitogen activated protein kinases (MAPKs) p38 and extracellular regulated kinase (ERK) as contributors to cPLA2 phosphorylation and activation, were examined at appropriate time points. To dissect out the cPLA2 interplay and dependencies with these MAPKs within the pathway context, the selective cPLA2 inhibitor arachidonyl trifluoromethyl ketone (AACOCF3) was employed and its effect on cell viability was examined. Fluorescence microscopy was used to substantiate cPLA2 activation, by assessing its cellular distribution, translocation and cell organelle target preference, using co-localization and z-stack techniques. In addition, the induction of the apoptotic pathway through analysis of caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage was examined. The role of caspase-3 in cPLA2 turnover was addressed employing the caspase inhibitor, Z-DEVD-FMK. Methods Cells were grown in Dulbecco’s Modified Eagles Medium (DMEM) with 10% fetal bovine serum (FBS), and incubated under 5% CO2 conditions, until 50%-70% confluent. Using DMEM supplemented with 1% horse serum, cell differentiation into myotubes was induced. Differentiated cells were preconditioned for 30 min classically, with 0.5 ng/ml TNF-α or the cPLA2 selective inhibitor AACOCF3 (10 μM) respectively. Followed by a 60 min washout period the cells were subjected to 8 hrs simulated ischaemia. Cellular viability; and cPLA2 phosphorylation- and translocation events were assessed using Western blots and advanced immunocytochemistry and imaging techniques. Results Preconditioning with TNF-α, ischaemic preconditioning; and the use of the cPLA2 inhibitor AACOCF3, attenuated the decrease is cell viability brough about by ischaemia. Western blot analysis indicates the induction of the apoptotic pathway with caspase-3 and PARP cleavage. A significantly reduced translocation of pcPLA2 to the nuclear region in the TNF-α preconditioned group compared to the ischaemic group, as reflected by reduced mean nuclear fluorescence intensity, was observed. A z-stack analysis confirmed that the nuclear and endonuclear region was the target organelle for cPLA2. 3-dimensional co-localazation analysis of pcPLA2 with the nuclear marker nucleoporin p62 mirrored these results. Discussion and conclusion Our results provide evidence that there is a role for cPLA2 in TNF-α mediated cytoprotection. Although we do not observe a differential activation pattern in terms of cPLA2 phosphorylation at various time points within the ischaemic event, and no differential inactivation of cPLA2 via caspase-mediated cPLA2 cleavage, we describe a differential cPLA2 translocation pattern, similar to that in IPC. Through inhibition of cPLA2 translocation, a functional cPLA2 inhibition might be achieved. This would imply inhibition of the inflammatory pathway and a subsequent reduction in the generation of inflammatory mediators. In addition we describe an effect of TNF-α preconditioning on the efficacy of the caspase inhibitor Z-DEVD-FMK. Our results shed light on the survival mechanisms employed by the ischaemically challenged cell in a setting of TNF-α mediated cytoprotection. This might lead to novel approaches in the context of inflammation treatment, through agents that control differential cPLA2 trafficking within the cell. / AFRIKAANSE OPSOMMING: Beide, die sitokien “Tumor Necrosis Factor-α (TNF-α)” en die ensiem, sitosoliese fosfolipase A2 (cPLA2) is uiters belangrike bemiddelaars van die sellulêre inflammatoriese respons en is verder ook betrokke by isgemiese selskade. TNF-α word endogeen gegenereer tydens ‘n isgemiese intervensie. Afgesien van ‘n verskeidenheid effekte, soos die inisiëring van apoptose, sel-proliferasie en - differensiasie, bemiddel dit ook selbeskermende meganismes indien dit in lae konsentrasies in die sel teenwoordig is. Na aktivering dra cPLA2 by tot die isgemiese intervensie deur die vorming van bemiddelaars van selskade en apoptose. Hierdie kalsium-afhanklike ensiem translokeer na die fosfolipied membraankomponent na stimulering en induseer die hidrolise van die sn-2 esterbinding in die fosfolipied. Die vrystelling van vry vetsure en lisofosfolipiede word sodoende bewerkstellig wat verder gemetaboliseer kan word tot inflammatoriese bemiddelaars. Ons stel voor dat cPLA2 ‘n rol in TNF-α bemiddelde selbeskerming speel en dat dit gepaardgaan met kenmerkende fosforilerings- en translokeringspatrone. Doelwitte Die rol van cPLA2 tydens TNF-α bemiddelde selbeskerming is in ‘n C2C12 skeletspiersellyn na blootstelling aan isgemie ondersoek. Die rol van die MAPKs, p38 en ERK, is ondersoek om vas te stel of hulle betrokke is by die aktivering van cPLA2. Die selektiewe cPLA2 inhibitor, AACOCF3, is gebruik om te bepaal of die fosforilering van MAPKs ook cPLA2-afhanklik is. Die sellulêre cPLA2 verspreiding, translokering en teiken selorganelle is ook ondersoek met behulp van fluoresensie mikroskopie deur gebruik te maak van ko-lokalisering en z-plaat tegnieke. Verder, is die indusering van die apoptotiese paaie ondersoek deur tegnieke wat kaspase- en PARP kliewing meet. Die kaspase inhibitor, Z-DEVD-FMK, is gebruik om vas te stel of kaspase-3 ‘n rol speel in cPLA2 kliewing in ons selmodel. Metodes Selle is gekweek in Dulbecco’s gemodifiseerde Eagles Medium (DMEM) waarby 10% fetale kalf serum (FBS) gevoeg is, en wat geïnkubeer is in 5% CO2 totdat dit 50%-70% konfluent was. Die selle is verder gedifferensieer in miobuise deur gebruik te maak van DMEM waarby 1% perdeserum gevoeg is. Gedifferensieerde selle is vir 30 min klassiek geprekondisioneer asook respektiewelik met 0.5 ng/ml TNF-α en die cPLA2 selektiewe inhibitor, AACOCF3 (10 μM). Na ‘n 60 minute uitwas periode is die selle blootgestel aan 8 h gesimuleerde isgemie. Sellulêre lewensvatbaarheid, cPLA2 fosforilering- and translokering is ondersoek deur onderskeidelik gebruik te maak van die “Western” klad metode en gesofistikeerde immunositochemiese beeld tegnieke. Resultate Prekondisionering met TNF-α, isgemiese prekondisionering asook inhibisie van as cPLA2 met die inhibitor, AACOCF3, het ‘n beduidende toename in sellewensvatbaarheid tot gevolg gehad. Daar is ook dmv die “Western” klad tegniek bewys dat apoptose geïduseer word deur middel van kaspase-3- en PARP kliewing. Daar is insiggewend minder translokasie van cPLA2 na die nukluêre fraksie in die isgemiese groep in vergelyking met die TNF-α geprekondisioneerde groep waargeneem (die gemiddelde nukluêre fluoreserende intensiteit is bepaal om voorafgaande feit te staaf). Die cPLA2 teiken organel is geverifieer as die nukleus en die endonukluêre gebied deur middel van z-plaat analises. Drie-dimensionele kolokaliserings analises van pcPLA2 met die nukluêre merker, nucleoporin p62 het hierdie resultate bevestig. Bespreking en Gevolgtrekking Ons resultate verskaf bewyse vir ‘n rol vir cPLA2 in TNF-α bemiddelde selbeskerming. Alhoewel daar nie ‘n differensiële aktiveringspatroon in terme van cPLA2 fosforilering tydens verskeie tydspunte in die isgemiese intervensie waargeneem is nie, en ook geen kaspase-3 bemiddelde kliewing van cPLA2 nie, word ‘n differensiële translokeringspatroon soorgelyk aan die isgemiese prekondisioneringsgroep, waargeneem. Funsksionele cPLA2 inhibisie kan dus moontlik bewerkstellig word deur inhibisie van cPLA2 translokasie. Die inflammatoriese respons kan dus moontlik so inhibieer word en die vorming van minder inflammatoriese bemiddelaars tot gevolg hê. Verder het TNF-α prekondisionering ook ‘n effek op die effektiwiteit van die kaspase-inhibitor, ZDEVD- FMK. Ons resultate werp ook lig op die meganismes wat deur selle onder isgemiese toestande uitgeoefen word tydens TNF-α bemiddelde selbeskerming. Hierdie resultate mag lei tot nuwe benaderings in die konteks van behandeling teen inflammasie deur gebruik te maak van middels wat cPLA2 translokering in die sel beheer.
223

An investigation into the P13-K/AKT signalling pathway in TNF-a-induced muscle proeolysis in L6 myotubes

Sishi, Balindiwe J. N. 12 1900 (has links)
Thesis (MSc (Physiological Sciences))--Stellenbosch University, 2008. / Introduction: Skeletal muscle atrophy is a mitigating complication that is characterized by a reduction in muscle fibre cross-sectional area as well as protein content, reduced force, elevated fatigability and insulin resistance. It seems to be a highly ordered and regulated process and signs of this condition are often seen in inflammatory conditions such as cancer, AIDS, diabetes and chronic heart failure (CHF). It has long been understood that an imbalance between protein degradation (increase) and protein synthesis (decrease) both contribute to the overall loss of muscle protein. Although the triggers that cause atrophy are different, the loss of muscle mass in each case involves a common phenomenon that induces muscle proteolysis. It is becoming evident that interactions among known proteolytic systems (ubiquitin-proteosome) are actively involved in muscle proteolysis during atrophy. Factors such as TNF-α and ROS are elevated in a wide variety of chronic inflammatory diseases in which skeletal muscle proteolysis presents a lethal threat. There is an increasing body of evidence that implies TNF-α may play a critical role in skeletal muscle atrophy in a number of clinical settings but the mechanisms mediating its effects are not completely understood. It is also now apparent that the transcription factor NF-κB is a key intracellular signal transducer in muscle catabolic conditions. This study investigated the various proposed signalling pathways that are modulated by increasing levels of TNF-α in a skeletal muscle cell line, in order to synthesize our current understanding of the molecular regulation of muscle atrophy. Materials and Methods: L6 (rat skeletal muscle) cells were cultured under standard conditions where after reaching ± 60-65% confluency levels, differentiation was induced for a maximum of 8 days. During the last 2 days, myotubes were incubated with increasing concentrations of recombinant TNF-α (1, 3, 6 and 10 ng/ml) for a period of 40 minutes, 24 and 48 hours. The effects of TNF-α on proliferation and cell viability were measured by MTT assay and Trypan Blue exclusion technique. Morphological assessment of cell death was conducted using the Hoechst 33342 and Propidium Iodide staining method. Detection of apoptosis was assessed by DNA isolation and fragmentation assay. The HE stain was used for the measurement of cell size. In order to determine the source and amount of ROS production, MitoTracker Red CM-H2 X ROS was utilised. Ubiquitin expression was assessed by immunohistochemistry. PI3-K activity was calculated by using an ELISA assay and the expression of signalling proteins was analysed by Western Blotting using phospho-specific and total antibodies. Additionally, the antioxidant Oxiprovin was used to investigate the quantity of ROS production in TNF-α-induced muscle atrophy. Results and Discussion: Incubation of L6 myotubes with increasing concentrations of recombinant TNF-α revealed that the lower concentrations of TNF-α used were not toxic to the cells but data analysis of cell death showed that 10 ng/ml TNF-α induced apoptosis and necrosis. Long-term treatment with TNF-α resulted in an increase in the upregulation of TNF- α receptors, specifically TNF-R1. The transcription factors NF-κB and FKHR were rapidly activated thus resulting in the induction of the ubiquitin-proteosome pathway. Activation of this pathway produced significant increases in the expression of E3 ubiquitin ligases MuRF-1 and MAFbx. Muscle fibre diameter appeared to have decreased with increasing TNF-α concentrations in part due to the suppressed activity of the PI3-K/Akt pathway as well as significant reductions in differentiation markers. Western blot analysis also showed that certain MAPKs are activated in response to TNF-α. No profound changes were observed with ROS production. Finally, the use Oxiprovin significantly lowered cell viability and ROS production. These findings suggest that TNF-α may elicit strong catabolic effects on L6 myotubes in a dose and time dependent manner. Conclusion: These observations suggest that TNF-α might have beneficial effects in skeletal muscle in certain circumstances. This beneficial effect however is limited by several aspects which include the concentration of TNF-α, cell type, time of exposure, culture conditions, state of the cell (disturbed or normal) and the cells stage of differentiation. The effect of TNF-α can be positive or negative depending on the concentration and time points analysed. This action is mediated by various signal transduction pathways that are thought to cooperate with each other. More understanding of these pathways as well as their subsequent upstream and downstream constituents is obligatory to clarify the central mechanism/s that control physiological and pathophysiological effects of TNF-α in skeletal muscle.
224

Body composition and systematic low-grade inflammation in children : the PLAY study / Rachelle A. Pretorius

Pretorius, Rachelle Ann January 2006 (has links)
Background: Obesity-related diseases are arising as a major problem among children. inflammation has recently been identified to play an important role in the relationship between obesity.- as well as stunting-related diseases. Objectives: The aim of this study was to assess the association between serum tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) concentrations and a variety of cardiometabolic and anthropometric indices of children in a township outside Potchefstroom, South Africa. Methods: Blood samples of 115 girls and 78 boys (mean age 15.6 ± 1.35) in the Physical Activity in the Young (PLAY) study were cross-sectionally analysed. Trained fieldworkers collected the demographic, Tanner growth stage and habitual physical activity information. Physiologists measured the children’s blood pressure. Anthropometric measurements were taken by. trained post-graduate students with level 1 or 2 qualifications in anthropometrics. A standard test battery was administered by trained postgraduate students in Human Movement Science to assess muscular strength. flexibility and endurance of the children. Blood samples were collected, centrifuged and stored frozen until further analyses. Results: Stunted girls had a significantly higher serum TNF-α concentration than the non-stunted girls (p=0.03). The factor analyses showed that the inflammatory. status clustered with the height for age-z-scores (HAZ) scores and the waist-hip-ratio (WHR). The HAZ-score of the over-fat boys (- 1.46) was significantly smaller than the lean boys (- 1.14, p=0.0 1). whereas the over-fat girls had a trend for a smaller HAZ-score (-1.07) than the lean girls (-0.89). No significant differences were found between the over-fat and the lean children-s inflammatory status. TNF-α and CRP levels tended to be higher in the over-fat children than in lean children. The girls' scrum IL-6 and CRP concentrations correlated significantly with their body mass index (BMI) and WHR (p<0.05 )and their TNF-α and IL-6 concentrations correlated significantly with their WHR (p<0.01 and p<0.05, respectively). Conclusion: In comparison to the non-stunted girls, stunted girls had a statistically significantly higher TNF-α concentration. Unusual fat distribution that is found in over-fat and stunted children may be associated with low-grade inflammation in children. More research is needed on these associations with markers of inflammation in a long-term longitudinal study. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2007.
225

Role of N-methyl-D-aspartate receptors in the regulation of human airway smooth muscle function and airway responsiveness

Anaparti, Vidyanand 15 June 2015 (has links)
Increased airway smooth muscle (ASM) mass contributes to airway hyperresponsiveness (AHR) in asthma and is orchestrated by growth factors, cytokines and chemokines. Airway contractile responses are influenced by neuromediators, such as acetylcholine, and glutamate released by parasympathetic and sympathetic airway nerves. Hyperactivity of these neural elements, termed neurogenic inflammation, is linked with hypercontractility and AHR. Glutamate is a non-essential amino acid derivative, and its physiological role is traditionally considered with respect to its being the primary excitatory neurotransmitter in brain, and regulation of neuronal development and memory. In allergic inflammation, immune cells including dendritic cells, neutrophils and eosinophils, constitutively synthesize and release glutamate, which signals through activation of glutamate receptors, most important among which are ionotrophic N-methyl D-aspartate receptors (NMDA-R). We hypothesized that glutamatergic signaling mediated through NMDA-Rs plays an important role in inducing functional Ca2+ responses in human (H) ASM cells that can underpin airway hypercontractility. We investigated the expression and function of NMDA-Rs in HASM cells, and assessed the effects of pro-inflammatory cytokines on NMDA-R expression and functional responses. Moreover, we measured airway responses to NMDA in mice, murine thin cut lung slice preparations, and floating collagen gels seeded with HASMs. Our data reveal that airway myocytes express multi-subunit NMDA-R complexes that function as receptor-operated calcium channels (ROCCs), mobilizing intracellular Ca2+ in ASM in vitro and airway contraction ex vivo. Individual airway myocytes treated with NMDA-R agonist exhibit disparate temporal patterns of intercellular Ca2+ flux that can be partitioned into four discrete function sub-groups. Further we show that tumor necrosis factor (TNF) exposure modulates NMDA-R subunit expression, and these changes are associated with a shift in the distribution of myocytes in individual Ca2+-mobilization sub-groups in vitro. Further, post-TNF exposure, NMDA-R agonists’ treatment induced Ca2+-dependent airway dilation in murine lung slice preparations, an effect that was prevented by co-treatment with inhibitors of nitric oxide synthase (NOS) or cyclooxygenase (COX). Taken together, we conclude that NMDA-R regulate HASM-mediated airway contraction and their role can be affected upon exposure to asthma-associated inflammatory mediators. Thus, NMDA-Rs are of relevance to mechanisms that determine airway narrowing and AHR associated with chronic respiratory diseases. / October 2015
226

Ischemická tolerance srdcí potkanů adaptovaných na chronickou hypoxii a fyzickou zátěž: úloha TNF-alfa. / Cardiac ischemic tolerance in rats subjected to adaptation to chronic hypoxia and physical exercise: the role of TNF-alpha.

Svatoňová, Anna January 2016 (has links)
Cardiovascular diseases represent the most important health risk factors because they are responsible for more than 50% of total mortality. Among them, the ischemic heart disease is leading cause of mortality. From the whole spectrum of different cardioprotective phenomena we have selected: 1) adaptation to chronic normobaric hypoxia (CNH) as the traditional experimental model in our laboratory area and 2) protective effect of exercise which in recent years represents promising and clinically relevant protective mechanism. The whole thesis is based on two studies. Aim of the first study was to characterize the expression of the main pro-inflammatory cytokine, TNF-α, in hearts of rats adapted to CNH. Chronic TNF-α inhibition by infliximab was used for discovering of certain role of TNF-α in CNH. We showed that increased myocardial level of TNF-α during adaptation to CNH was contributed via its receptor TNFR2 and nuclear factor κB-dependent activation of protective redox signalling with increased antioxidant defence. This adaptive pathway participates on the infarct size-limiting effect of CNH. Aim of the second study was find out whether exercise training and CNH could play synergy in cardiac protection in rats model. We reported that CNH and exercise reduced infarct size but their combination...
227

Associação entre graus de mucosite e quantificação da interleucina 6 (IL- 6) e fator de necrose tumoral alfa (TNF-?) na saliva de pacientes submetidos a transplante de células-tronco hematopoiéticas (TCTH) / Association between degree of oral mucositis and quantification of interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-?) in patients undergoing haematopoietic stem cell transplantation (HSCT)

Silva, Paula Verona Ragusa da 25 July 2016 (has links)
A mucosite oral (MO) constitui uma condição dolorosa que se desenvolve entre 47% e 100% dos pacientes submetidos a transplante de células-tronco hematopoiéticas (TCTH), impactando enormemente em sua qualidade de vida. Investigar fatores preditivos para MO por meio de exames não invasivos faz-se necessário, visando melhorar a qualidade de vida dos pacientes. O objetivo do estudo foi investigar a relação dos regimes de condicionamento e dos níveis salivares de Interleucina 6 (IL- 6) e Fator de Necrose Tumoral alfa (TNF-?) com a MO, bem como investigar o impacto destes na qualidade de vida. Foram selecionados 82 pacientes submetidos a TCTH, que foram avaliados em 4 momentos diferentes: no início do condicionamento para o TCTH (M1), no dia da infusão das células (M2), após 12/20 dias do início do condicionamento para transplante autólogo e alogênico, respectivamente (M3), e após 30 dias ou na alta hospitalar para ambos (M4). Nestes momentos, foi avaliado clinicamente o grau de MO segundo critérios da Organização Mundial da Saúde (OMS), coletada saliva total e aplicados 3 questionários de avaliação de qualidade de vida em relação à MO e à saúde bucal: PROMS, OHIP-14 e OMQoL. As informações clínicas e laboratoriais foram correlacionadas através do STATA 13.0 com 5% de nível de significância. Verificou-se que a maior incidência e intensidade de MO, os piores índices de qualidade de vida e os maiores níveis de IL- 6 e TNF-? foram registrados no M3, porém não houve correlação entre as citocinas e graus de MO. Houve associação entre altos níveis salivares de IL-6 e maiores pontuações no PROMS. O regime de condicionamento mieloablativo (ML) foi relacionado à MO intensa (graus 3 e 4) e à maiores pontuações nos 3 questionários de qualidade de vida, e os escores dos questionários foram maiores conforme maior foi intensidade da MO (p<0,05). / Oral mucositis (OM) is a painful condition that develops between 47% and 100% of patients undergoing hematopoietic stem cell transplantation (HSCT), impacting greatly on their quality of life. Investigation of predictive factors for OM through noninvasive exams is necessary, in order to improve the quality of life of patients. The aim of the study was to investigate the relationship of conditioning regimens and salivary levels of Interleukin 6 (IL-6) and Tumor Necrosis Factor alpha (TNF-?) with OM, and to investigate their impact on quality of life. We selected 82 patients undergoing HSCT, which were assessed at four different moments: at the start of conditioning for HSCT (M1), on the cell infusion day (M2), after 12/20 days of the start of conditioning for autologous and allogeneic transplantation, respectively (M3), and after 30 days or at hospital discharge for both (M4). In these moments, it was clinically evaluated the degree of OM according to criteria of the World Health Organization (WHO), collected whole saliva and applied 3 questionnaires of assessment of quality of life related to OM and oral health: PROMS, OHIP-14 and OMQoL. Clinical and laboratorial data were correlated using STATA 13.0 in a 5% significance level. It was found that the highest incidence and intensity of OM, the worst indices of quality of life and higher IL-6 and TNF-? levels were found in M3, but there was no correlation between cytokines and levels of OM. There was an association between high levels of salivary IL-6 and higher scores in PROMS. The myeloablative conditioning regimen (ML) was related to intense OM (grades 3 and 4) and to highest scores in the 3 questionnaires of quality of life, and the scores of questionnaires were higher as higher was the intensity of OM (p<0,05).
228

Polimorfismos do fator de necrose tumoral alfa, da interleucina-18 e do interferon gama na coinfecção HIV/HCV / Polymorphisms of the tumor necrosis factor-alpha, of the interleukin-18 and of the interferon-gamma in HIV/HCV coinfection

Tsuda, Luciana Castelar 07 August 2015 (has links)
As complicações hepáticas secundárias à infecção crônica pelo vírus da hepatite C (HCV) são uma importante causa de morte em portadores da infecção pelo vírus da imunodeficiência humana (HIV). Pacientes com coinfecção HIV/HCV apresentam progressão acelerada da fibrose hepática, na qual há participação da resposta inflamatória do sistema imunológico, e requerem maior atenção no tratamento da hepatite C e de suas reações adversas. Assim, os objetivos principais do estudo foram tipificar e comparar os polimorfismos -607 e -137 da interleucina-18 (IL-18), +874 do interferon gama (IFN-?? e -308 e -238 do fator de necrose tumoral alfa (TNF- ?? em quatro grupos (coinfecção HIV/HCV, monoinfecção pelo HIV, monoinfecção pelo HCV e controles saudáveis); investigar a associação dos alelos e genótipos desses polimorfismos com a resposta ao tratamento da hepatite C (respondedor e não respondedor), graus de atividade necroinflamatória (METAVIR A0A1 vs. A2A3) e de fibrose hepática (METAVIR F0-F2 vs. F3F4) em portadores do HCV e identificar os sinais e sintomas relacionados às reações adversas do tratamento da hepatite C. Os dados foram coletados nos prontuários médicos e no sistema informatizado do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto e os polimorfismos tipificados pela técnica de reação em cadeia da polimerase com iniciadores de sequência específica. Participaram do estudo 400 indivíduos, distribuídos em quatro grupos de 100, predominantemente constituídos por homens com idade média entre 33 e 50 anos. Na avaliação geral, os genótipos -238 G/G (TNF-?? e +874 A/A (IFN-?? foram mais frequentes no grupo coinfecção HIV/HCV em relação ao monoinfecção pelo HCV. O genótipo -308 G/A e o alelo -308 A (TNF-?? foram associados com a susceptibilidade à coinfecção HIV/HCV e o genótipo -308 G/G e o alelo -308 G (TNF-?), com proteção. No grupo coinfecção HIV/HCV, a frequência do genótipo - 137 G/C (IL-18) foi maior nos sujeitos com atividade necroinflamatória A0A1 que nos com A2A3. Nos pacientes com fibrose F3F4, o genótipo -238 G/G (TNF-?? foi mais frequente no grupo coinfecção HIV/HCV que no monoinfecção pelo HCV e naqueles com F0-F2, o genótipo +874 A/A (IFN-?? também foi mais frequente no grupo coinfecção HIV/HCV. A frequência do genótipo +874 T/T (IFN-??, dentre os pacientes do grupo coinfecção HIV/HCV, foi maior naqueles com fibrose F3F4 que nos com F0-F2. Não foram encontradas associações estatisticamente significantes entre as frequências alélicas e genotípicas e os tipos de resposta ao tratamento da hepatite C nos pacientes do grupo coinfecção HIV/HCV; nos do monoinfecção pelo HCV, houve diferenças nas frequências alélicas e genotípicas (posição -238 do TNF-?) entre pacientes respondedores e não respondedores. Os principais sinais e sintomas relacionados às reações adversas do tratamento da hepatite C foram mialgia, febre, fraqueza, cefaleia e hiporexia. Anemia, hiporexia e vômito foram mais frequentes no grupo coinfecção HIV/HCV. Conclui-se que há relação dos alelos e genótipos de citocinas com a gravidade da doença hepática e resposta ao tratamento da hepatite C. Adicionalmente, algumas reações adversas ao tratamento foram mais pronunciadas em coinfectados HIV/HCV / Hepatic complications secondary to chronic infection by hepatitis C virus (HCV) are a major cause of death in people infected by the human immunodeficiency virus (HIV). Patients with HIV/HCV coinfection present rapid progression of liver fibrosis, with involvement of the immune system\'s inflammatory response, and require more attention in hepatitis C treatment and its adverse reactions. The main goals of this study were to typify and compare the polymorphisms -607 and -137 of the interleukin-18 (IL-18), +874 of the interferon gamma (IFN-?? and -308 and -238 of the tumor necrosis factor-alpha (TNF-?? in four groups (HIV/HCV coinfection, HIV monoinfection, HCV monoinfection and healthy controls), to investigate the association of the alleles and genotypes of these polymorphisms with response to hepatitis C treatment (responder and non-responder), degrees of necroinflammatory activity (METAVIR A0A1 vs. A2A3) and of liver fibrosis (METAVIR F0-F2 vs. F3F4) in HCV patients and to identify the signs and symptoms related to adverse reactions of hepatitis C treatment. Data were collected on medical records and on the computerized system of the Hospital das Clínicas of the University of São Paulo Ribeirão Preto Medical School and the polymorphisms were typified using the polymerase chain reaction technique with sequence specific primers. The study included 400 individuals, distributed in four groups of 100, predominantly consisting of men with an average age between 33 and 50 years. In the overall evaluation, genotypes -238 G/G (TNF-?? and +874 A/A (IFN-?? were more frequent in the HIV/HCV coinfection group compared to HCV monoinfection. The genotype -308 G/A and allele -308 A (TNF-?? were associated with susceptibility to HIV/HCV coinfection and the genotype -308 G/G and allele -308 G (TNF-?), with protection. In the HIV/HCV coinfection group, the frequency of genotype -137 G/C (IL-18) was greater in subjects with necroinflammatory activity A0A1 than in the ones with A2A3. In patients with fibrosis F3F4, genotype -238 G/G (TNF-?? was more frequent in the HIV/HCV coinfection than in the HCV monoinfection group and in those with fibrosis F0-F2, genotype +874 A/A (IFN-?? was also more frequent in the HIV/HCV coinfection group. The frequency of genotype +874 T/T (IFN-??, among patients of the HIV/HCV coinfection group, was higher in those with fibrosis F3F4 compared to the ones with F0-F2. No statistically significant associations were found between the allele and genotype frequencies and the types of answer to hepatitis C treatment in patients of the HIV/HCV coinfection group. On the ones of the HCV monoinfection group, there were differences on the allele and genotype frequencies (position -238 of TNF-?? among responder and non-responder patients. The main signs and symptoms related to adverse reactions to hepatitis C treatment were myalgia, fever, weakness, headache and loss of appetite. Anemia, loss of appetite and vomiting were more frequent in the HIV/HCV coinfection group. It is concluded that there is relationship of the alleles and genotypes of cytokines with the severity of liver disease and response to hepatitis C treatment. Additionally, some adverse reactions to treatment were more frequent in HIV/HCV coinfected patients
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Avaliação do efeito do bloqueio de Fator de Necrose Tumoral alfa (TNF-) na resposta imune in vitro aos antígenos de Mycobacterium tuberculosis em pacientes com psoríase / Evaluation of the effect of TNF-alpha inhibitors in the in vitro immune response to Mycobacterium tuberculosis antigens in patients with psoriasis

Silva, Léia Cristina Rodrigues da 06 November 2008 (has links)
O Fator de Necrose Tumoral-alfa (TNF-alfa) possui um importante papel na imunopatogênese da psoríase e agentes biológicos, como os inibidores de TNF-alfa, têm apresentado bons resultados no tratamento desta. No entanto, estes agentes foram associados ao aumento de casos de reativação de tuberculose entre os pacientes que os utilizaram. Este estudo foi realizado com o intuito de avaliar a resposta imune de pacientes com psoríase grave, ativa, sem tratamento, frente a antígenos de Mycobacterium tuberculosis (Mtb), e o efeito dos inibidores de TNF-alfa nesta resposta. Estudamos 24 pacientes com psoríase grave divididos em 2 grupos: não reatores (n = 14) e reatores (n = 10) ao teste intradérmico com PPD. Como controle, utilizamos um total de 26 indivíduos sadios, também separados em 2 grupos segundo a reatividade ao PPD (PPD-, n = 13; PPD+, n = 13). Em uma segunda etapa estudamos 11 pacientes com psoríase leve a moderada, também sem tratamento, PPD (-) para avaliarmos a importância da gravidade da psoríase na resposta aos antígenos micobacterianos. Avaliamos a resposta imunológica in vitro através da linfoproliferação, quantificação da produção de IFN-gama (ELISA) e quantificação de células produtoras de IFN-gama (ELISPOT), na presença e ausência dos inibidores de TNF-alfa (infliximab e etanercepte), utilizando os antígenos purificados ESAT-6, Ag85B e o antígeno bruto sonicado da cepa H37Rv (AgSMtb), e o mitógeno fitohemaglutinina (PHA). Os pacientes com psoríase grave PPD (-) apresentaram reposta linfoproliferativa e níveis de IFN-gama menores que nos controles PPD (-). Os pacientes com psoríase leve a moderada apresentaram resposta imune intermediária entre controles e pacientes graves. Em relação aos inibidores de TNF- alfa, verificou-se que infliximab e etanercepte apresentaram diferença em suas capacidades de inibição, sendo que somente o infliximab ocasionou a inibição total de TNF-alfa. Em contrapartida o etanercept manteve a produção de TNF-alfa, e em alguns casos elevou sua produção. Estes diminuíram apenas parcialmente a reatividade in vitro dos pacientes com psoríase, uma vez que a secreção de IFN-gama e o número de células produtoras de IFN-gama não foram alterados na presença dos inibidores. A secreção de IL-10 foi diminuída tanto na presença do infliximab, quanto na presença do etanercepte. Os dados obtidos permitem concluir que (a) os pacientes com psoríase grave PPD (-) apresentam uma baixa reatividade in vitro, principalmente das respostas que avaliam linfócitos T de memória central, aos antígenos de Mtb, sendo que essa baixa reatividade não está totalmente relacionada com a gravidade da doença, uma vez que os pacientes com psoríase leve a moderada apresentaram resposta intermediária a dos controles e pacientes com psoríase grave; (b) e que apesar dos inibidores de TNF- alfa promoverem uma inibição parcial da resposta imune, a reativação da tuberculose estaria mais relacionada à própria ausência de TNF-alfa, não compensada pela atuação isolada, e provavelmente insuficiente, de IFN-gama na manutenção do granuloma, do que a outras substanciais modificações na resposta imunológica frente aos antígenos micobacterianos. / Tumor necrosis factor alpha (TNF-alpha) has a pivotal role in psoriasis pathogenesis and biologic agents, such as TNF-alpha inhibitors, have provided good results in its treatment. However, the use of these agents has been associated with an increase in the number of cases of tuberculosis reactivation. This study aimed to evaluate the immune response of severe psoriasis patients, with active, untreated disease to relevant Mycobcterium tuberculosis antigens, and the effect of the TNF-alpha inhibitors (infliximab and etanercept) in this response. Twenty four severe psoriasis patients were enrolled and divided in two groups according to their reactivity to the tuberculin skin test: TST (n= 14) and TST + (n=10). As controls, we studied 26 healthy donors, also divided in two groups to the TST reactivity (TST -, n=13; TST+, n=13). Eleven mild to moderate psoriasis patients, untreated, TST (-) were studied to evaluated the role of psoriasis severity in the immune response to the mycobacterial antigens. Immune responses were evaluated in vitro by the lymphocyte proliferative response (LPR) assay, ELISA for IFN-? secretion by peripheral blood mononuclear cells and enumeration of IFN-? secreted cells (ELISPOT) induced in response to the purified antigens ESAT-6, Ag85B and a crude sonicated antigen preparation from H37Rv Mtb strain (AgSMtb), as well as to the mitogen phytohemagglutinin (PHA), in the presence or absenceinflimab/etanercept. The LPR and IFN-g secretion to Mtb antigens were lower in TST- severe psoriasis patients than TST- controls. Mild to moderate psoriasis patients had intermediate responses, between controls and severe psoriasis patients. The TNF-a inhibitors infliximab and etanercept showed differences in their inhibitiory activity, since only infliximab was capable to neutralize all TNF-a. On the other hand, etanercept kept TNF-alpha production, and in some cases even increased its production. The TNF-alpha inhibitors diminished partially the in vitro patients immune responses, since the IFN-? secretion and enumeration of IFN-? secreted cells were not affected. IL-10 secretion was diminished with both TNF-a inhibitors. In conclusion: (a) TST(-) severe psoriasis patients have decreased in vitro reactivity, mainly in those responses that evaluate central memory T-cell responses, to Mtb antigens, and this decrease could not be fully explained by disease severity, since mild psotiasis patients had intermediate responses; (b) and despite the fact that TNF-alpha inhibitors promote a partial immune response inhibition, tuberculosis reactivation could be related more with the lack of TNF-alpha, which was probably not compensated by the IFN-g activity alone, probably insufficient, to the support granuloma formation, than other defects of the immune response to Mtb antigens.
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Einfluß genetischer Variationen im Tumor Nekrose Faktor-alpha Gen auf die Progession der HIV-Infektion und die Entstehung HIV-assoziierter Krankheiten

Schüttlöffel, Antje 08 January 2002 (has links)
Fragestellung: Wir gingen der Frage nach, inwieweit genetische Variationen im Gen für den Tumor Nekrose Faktor-alpha einen Einfluß auf die Krankheitsprogression oder die Entstehung bzw. Ausprägung HIV-assoziierter Erkrankungen haben. Methoden: Die Promotorregion sowie die kodierenden Sequenzen des TNF-alpha-Gens wurden mittels SSCP-Analyse auf genetische Variationen untersucht. Anschließend erfolgte die Charakterisierung der häufigsten bekannten Promotorpolymorphismen mittels Restriktionsfragment-Längenpolymorphismus-Analyse (RFLP). Die Bestätigung der Polymorphismen der RFLP-Analyse erfolgte an ausgewählten Proben durch DNA-Fluoreszenzsequenzierung. In sämtlichen Fällen handelte es sich um singuläre Basentransitionen von Guanin zu Adenin. Ergebnisse: Unter Einbeziehung verschiedener Progressionsparameter wie der CD4-Zellzahl, des Zeitraumes vom ARC-Stadium zum AIDS-Stadium und AIDS-assoziierter Krankheiten wie dem Wasting Syndrom und der HIV-Enzephalopathie, erfolgte anschließend die statistische Analyse in Korrelation mit den ermittelten Genotypen. Es zeigte sich bei keiner der statistischen Analysen eine signifikante Assoziation mit einem bestimmten TNF-alpha-Genotyp. Schlußfolgerung: Es ist kritisch anzumerken, daß für einige Subanalysen die Größe der untersuchten Patientengruppe zu gering war, um eine statistische Aussagekraft für seltene Allele zu erreichen. Anhand der hier vorgelegten Ergebnisse hat der TNF-alpha-Genotyp weder einen Einfluß auf die Progression der HIV-Erkrankung noch auf die Ausbildung HIV-assoziierter Erkrankungen wie dem Wasting Syndrom oder der HIV-Enzephalopathie. / Objective: We determined whether variation of the tumor necrosis factor-alpha gene had an impact on HIV disease progression or the prevalence of hiv-associated diseases. Methods: The promotor region of the TNF-alpha gene were examined with SSCP analysis for polymorphisms in the promotor region. The most common promotor polymorphisms were characterized with restriction fragment length polymorphism analysis (RFLP). To confirm RFLP results DNA fluorescence sequenzing analyses were performed with selected samples. In all cases with diagnosis of promotor polymorphisms single base transitions from guanine to adenine were confirmed. Results: Statistical analyses correlated the genotypes with different markers for disease progression e.g. CD4-count, the period from ARC to AIDS and the occurance of HIV associated diseases (wasting syndrome, hiv encephalopathy). In none of the statistical analyses significant association with a certain TNF-alpha genotyp could be demonstrated. Conclusion: For some subanalysis the sample sizes were too small in order to be able to make safe statistical statements concerning rare allels. Regarding our results, none of the examined tumor necrosis factor-alpha promotor polymorphisms had an impact on HIV disease progression or the prevalence of hiv-associated diseases.

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