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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.
491

An Applied Mathematics Approach to Modeling Inflammation: Hematopoietic Bone Marrow Stem Cells, Systemic Estrogen and Wound Healing and Gas Exchange in the Lungs and Body

Cooper, Racheal L 01 January 2015 (has links)
Mathematical models apply to a multitude physiological processes and are used to make predictions and analyze outcomes of these processes. Specifically, in the medical field, a mathematical model uses a set of initial conditions that represents a physiological state as input and a set of parameter values are used to describe the interaction between variables being modeled. These models are used to analyze possible outcomes, and assist physicians in choosing the most appropriate treatment options for a particular situation. We aim to use mathematical modeling to analyze the dynamics of processes involved in the inflammatory process. First, we create a model of hematopoiesis, the processes of creating new blood cells. We analyze stem cell collection regimens and statistically sample parameter space in order to create a model accounts for the dynamics of multiple patients. Next, we modify an existing model of the wound healing response by introducing a variable for two inflammatory cell types. We analyze the timing of the inflammatory response and introduce the presence of systemic estrogen in the model, as there is evidence that the presence of estrogen leads to a more efficient wound healing response. Last, we mathematically model the gas exchange process in the lungs and body in order to lay the foundation for a model of the inflammatory response in the lung under conditions of mechanical ventilation. We introduce normal and ventilation breathing waveforms and a third state of hemoglobin in a closed loop partial differential equations model. We account for gas exchange in the lung and body compartments in addition to introducing a third discretized well-mixing compartment between the two. We use ordinary and partial differential equations to model these systems over one or more independent variables, as well as classical analysis techniques and computational methods to analyze systems. Statistical sampling is also used to investigate parameter values in order for the mathematical models developed to account for patient-to-patient variability. This alters the traditional mathematical model, which yields a single set of parameter values that represent one instance of the physiology, into a mathematical model that accounts for many different instances of physiology.}
492

Establishing a Robust In Vitro Embryonic Stem Cell Differentiation Assay to Monitor the Hematopoietic Potential of DELES Clones

Shetty, Swati 01 1900 (has links)
Afin d’effectuer des études fonctionnelles sur le génome de la souris, notre laboratoire a généré une bibliothèque de clones de cellules souches embryonnaires (ESC) présentant des suppressions chromosomiques chevauchantes aléatoires – la bibliothèque DELES. Cette bibliothèque contient des délétions couvrant environ 25% du génome murin. Dans le laboratoire, nous comptons identifier de nouveaux déterminants du destin des cellules hématopoïétiques en utilisant cet outil. Un crible primaire utilisant la benzidine pour démontrer la présence d'hémoglobine dans des corps embryoïdes (EBS) a permis d’identifier plusieurs clones délétés présentant un phénotype hématopoïétique anormal. Comme cet essai ne vérifie que la présence d'hémoglobine, le but de mon projet est d'établir un essai in vitro de différenciation des ESC permettant de mesurer le potentiel hématopoïétique de clones DELES. Mon hypothèse est que l’essai de différenciation hématopoïétique publié par le Dr Keller peut être importé dans notre laboratoire et utilisé pour étudier l'engagement hématopoïétique des clones DELES. À l’aide d’essais de RT-QPCR et de FACS, j’ai pu contrôler la cinétique de différenciation hématopoïétique en suivant l’expression des gènes hématopoïétiques et des marqueurs de surface comme CD41, c-kit, RUNX1, GATA2, CD45, β-globine 1 et TER-119. Cet essai sera utilisé pour valider le potentiel hématopoïétique des clones DELES candidats identifiés dans le crible principal. Mon projet secondaire vise à utiliser la même stratégie rétro-virale a base de Cre-loxP utilisée pour générer la bibliothèque DELES pour générer une bibliothèque de cellules KBM-7 contenant des suppressions chromosomiques chevauchantes. Mon but ici est de tester si la lignée cellulaire leuémique humaine presque haploïde KBM-7 peut être exploitée en utilisant l'approche DELES pour créer cette bibliothèque. La bibliothèque de clones KBM-7 servira à définir les activités moléculaires de drogues anti-leucémiques potentielless que nous avons identifiées dans le laboratoire parce qu’elles inhibent la croissance cellulaire dans plusieurs échantillons de leucémie myéloïde aiguë dérivés de patients. Elle me permettra également d'identifier les voies de signalisation moléculaires qui, lorsque génétiquement perturbées, peuvent conférer une résistance à ces drogues. / To carry out functional studies on the mouse genome, our laboratory has generated a library of Embryonic Stem Cell (ESC) clones harboring random nested chromosomal deletions – DELES library. This library contains deletions covering ~ 25% of the mouse genome. In the lab, we are interested in identifying novel hematopoietic cell fate determinants using this resource. A primary screen using benzidine to demonstrate the presence of hemoglobin in embryoid bodies (EBs) was able to identify several DELES clones exhibiting abnormal hematopoietic phenotype. Since this assay only tested for the presence of hemoglobin, the goal of my project is to establish a robust in vitro ESC differentiation assay to monitor the hematopoietic potential of DELES clones. My hypothesis is that the hematopoietic differentiation assay published by Dr. Keller can be used to observe hematopoietic commitment of the DELES clones. Using QRT-PCR and FACS assays I was able to monitor the kinetics of hematopoietic differentiation by observing the expression of hematopoietic genes and surface markers including CD41, C-KIT, RUNX1, GATA2, CD45, β-GLOBIN 1 and TER-119. This assay will be used to validate the hematopoietic potential of the candidate DELES clones identified in the primary screen. My secondary project aims to use the same retro-viral Cre-loxP strategy used for the DELES library, in order to generate a library of KBM-7 leukemic cells harboring nested chromosomal deletions. My goal here is to test if the human near haploid KBM-7 cell line can be exploited using the DELES approach to create this library. The library of KBM-7 clones will be used to delineate the molecular activities of potential anti-leukemic drugs that we have identified in the lab to inhibit cell growth in several patient-derived acute-myeloid leukemia specimens. It will also allow me to identify molecular signaling pathways that, when genetically disrupted, can confer resistance to these drugs.
493

Expanding and defining human hematopoietic stem and progenitor cells ex vivo using small molecules

Fares, Iman 04 1900 (has links)
Human hematopoietic stem cells (HSCs) are defined by their capacity to self-renew and to differentiate into all blood lineages during an adult lifetime. Based on these unique properties, HSCs are used in transplantation procedures to treat various hematological diseases. However, the low number of HSCs in a graft limits the use of this treatment. To overcome this restrain, different approaches were established to expand HSCs ex vivo; yet, the absence of a reliable surface maker that correlates with HSC activity in culture made the assessment labor-intensive and time-consuming. Using a library of small molecules, we were able to identify pyrimidoindole derivative named UM171 as an agonist for HSC self-renewal. UM171 promotes ex vivo expansion of hematopoietic and stem cell progenitors (HSPC) independently of AhR suppression- a pathway reported by Boitano et al. to have the greatest effect in HSC expansion. Unlike AhR suppression that targets a hematopoietic population with limited proliferative potential, UM171 targets the long-term HSCs. Transcriptome analysis showed that UM171 reduces the levels of transcripts associated with lineage differentiation and induces the expression of genes encoding for membrane proteins, one of the best differentially expressed being the endothelial protein c receptor (EPCR). Cell sorting and transplantation experiments of EPCR expressing cells showed a high correlation with HSC activity. We demonstrated EPCR as a first reliable marker to enrich for HSC in culture and that it is required for HSPC function in vivo. These findings provide a valuable tool for clinical and research applications to optimize further HSPC expansion protocols and understand the molecular machinery that governs the HSC self-renewal. / Le terme de cellules souches hématopoïétiques (CSH) désigne une population rare de cellules capables de générer l’ensemble des lignages hématopoïétiques. Cette définition implique une capacité d’auto-renouvèlement, ainsi qu'un potentiel de prolifération et de différenciation important. La greffe de cellules souches hématopoïétiques est aujourd'hui une modalité thérapeutique pour le traitement de diverses maladies hématologiques et représente pour de nombreux patients un traitement de dernier recours. Malheureusement, le nombre limité de ces cellules dans une unité de sang de cordon est à l’origine du faible taux de réussite des greffes de sang de cordon chez l'adulte. Plusieurs stratégies sont actuellement mises en place pour permettre la multiplication de ces CSH ex vivo. Cependant, Il n’y a jusqu’à ce jour aucun critère ou marqueur phénotypique fiable permettant spécifiquement d'identifier ou d'isoler ces CSH amplifiées, et leur caractérisation reste un défi majeur pour les chercheurs. Dans le laboratoire, nous avons effectué un criblage à haut débit afin de tester le potentiel d’un grand nombre de molécules chimiques à multiplier des cellules souches dérivées de sang de cordon ombilical et nous avons ainsi identifié la molécule UM171, un dérivé pyrimido-indole, qui permet de multiplier par 10 le nombre de CSH et par 100 leur descendance. Nous avons démontré qu' UM171 permet de multiplier les CSH sans affecter la voie de signalisation de la protéine AhR, récemment impliquée dans l'auto-renouvèlement des CSH. L'analyse du transcriptome des CSH exposées à la molécule UM171 a permis d'identifier le récepteur endothélial à la protéine C (EPCR), comme marqueur de surface permettant de prédire le nombre et l'activité des CSH en culture et par conséquent de les isoler et de mieux les caractériser. En combinant des techniques de cytométrie de flux et d'ARN interférents avec des expériences de transplantation à long terme dans des souris immuno-déficientes, nous avons pu démontrer qu' EPCR peut être considéré non seulement comme un premier marqueur fiable pour enrichir les CSH en culture mais aussi qu'il est nécessaire pour la fonction de ces CSH in vivo. Les résultats de ces travaux représentent une avancée majeure pour accélérer les recherches et les applications cliniques sur l'expansion des CSH ex vivo et permettra de comprendre les mécanismes moléculaires qui régissent l'auto-renouvèlement des CSH.
494

Rôle de la protéine TRRAP, co-facteur des HATs, dans la régulation de la pluripotence des cellules souches embryonnaires et hématopoiétiques / TRRAP : an essential player in the regulation of stemness in embryonic and hematopoietic stem cells

Sawan-Vaissière, Carla 22 September 2010 (has links)
Les cellules souches embryonnaires et adultes sont strictement contrôlées et régulées par différents mécanismes comme l’auto-renouvellement, la différentiation et l’apoptose. Les enzymes impliquées dans la modification des histones et les différents statuts de la chromatine seraient responsables de la mise en place, du maintien et de la propagation des différents profils d’expression des gènes mais le mécanisme sous-jacent reste néanmoins mal compris. Dans nos études, nous avons identifié le rôle de Trrap, un cofacteur des histones acétyltransférases dans le maintien de l’auto-renouvellement des cellules souches embryonnaires et adultes. La perte de la moelle épinière et une mortalité croissante sont survenues suite à la délétion conditionnelle du gène Trrap chez la souris. Ceci est dû à la perte des cellules hématopoïétiques progénitrices ainsi que des cellules hématopoïétiques souches par un mécanisme cellulaire autonome. L’analyse des cellules progénitrices, purifiées, de la moelle épinière à permis de révéler que ces anomalies sont associées à l’induction de l’apoptose indépendante de p53 ainsi qu’à la dérégulation des facteurs de transcription Myc. De plus, la délétion conditionnelle de Trrap dans les cellules souches embryonnaires induit la différentiation due au rôle important que Trrap joue dans la régulation du couplage de la méthylation de l’histone H3 aux lysines K4 et K27 appelées « domaines bivalents », le maintien du statut hyperdynamique de la chromatine et la régulation des gènes spécifiques à l’auto-renouvellement. Ceci est cohérent avec l’essentiel rôle de Trrap impliqué dans le mécanisme qui restreint l’induction de l’apoptose ou de la différentiation, ceci selon le type de cellules souches, et favorise le maintien de l’auto-renouvellement. Ces études ont permis d’identifier les différents rôles essentiels que Trrap joue dans le mécanisme qui permet le maintien des cellules souches embryonnaires et adultes ce qui soulève la possibilité que Trrap et les modifications des histones qui contrôlent l’auto-renouvellement pourraient être importants pour le développement et le maintien des cellules souches cancéreuses. Une meilleure compréhension du mécanisme commun qui implique Trrap et les modifications des histones contrôlant les éléments essentiels des cellules souches normales et cancéreuses s’avèrerait essentiel et très bénéfique pour les stratégies de thérapies épigénétiques qui ont pour but d’éradiquer les cellules souches cancéreuses / Embryonic and adult stem cells are tightly controlled and regulated by self-renewal, differentiation and apoptosis. Histone modifiers and chromatin states are believed to govern establishment, maintenance, and propagation of distinct patterns of gene expression in stem cells, however the underlying mechanism remains poorly understood. In our studies, we identified a role for the histone acetyltransferase cofactor Trrap in the maintenance of embryonic stem cells and hematopoietic stem/progenitor cells. Conditional deletion of the Trrap gene in mice resulted in ablation of bone marrow and increased lethality. This was due to the depletion of early hematopoietic progenitors, including hematopoietic stem cells, via a cell-autonomous mechanism. Analysis of purified bone marrow progenitors revealed that these defects are associated with induction of p53-independent apoptosis and deregulation of Myc transcription factors. Moreover, conditional deletion of Trrap in embryonic stem cells was found to results in unscheduled differentiation. This was due to the essential role of Trrap in coupling of H3K4 and H3K27 methylation ("bivalent-domains"), the maintenance of hyperdynamic chromatin state and regulation of the stemness genes, consistent with the essential function of Trrap in the mechanism that restricts apoptosis or differentiation depending on stem cell type and promotes the maintenance of self-renewal. Together, these studies have identified critical roles for Trrap in the mechanism that maintains embryonic and hematopoietic stem cells and raise the possibility that Trrap and histone modifications controlling self-renewal may be important for the development and maintenance of cancer stem cells. Better understanding of a common molecular mechanism involving HATs and histone modifications that controls key features of normal and cancer stem cells may prove highly beneficial for epigenetics-based therapeutic strategies aiming to eradicate cancer stem cells
495

Influência do envelhecimento das células-tronco mesenquimais na autorrenovação, diferenciação e multipotência de células-tronco hematopoéticas / Mesenchymal stem cells aging influence in the self-renewal, differentiation and multipotency of hematopoietic stem cells

Benedito, Suzana da Silva 05 September 2016 (has links)
O envelhecimento é um processo gradual e intrínseco que ocorre devido a mudanças fisiológicas e fenotípicas com o avanço da idade e que acarreta na diminuição da capacidade de manter a homeostase e reparo tecidual. A perda do controle homeostático e o possível envolvimento de células-tronco e progenitores, provavelmente, é uma das causas das fisiopatologias do sistema hematopoético que acompanham o envelhecimento. O declínio na competência do sistema imune adaptativo, o aumento de doenças mielóides, leucemias e o desenvolvimento de anemias são algumas mudanças significantes e decorrentes do processo de envelhecimento. Durante a transição ontológica, a habilidade de células-tronco hematopoéticas originarem células progenitoras diminui progressivamente, sugerindo perda da capacidade de autorrenovação e diferenciação das células-tronco com o avanço da idade. O microambiente medular se divide em duas áreas distintas: nicho endosteal e nicho vascular, conhecidos por controlar a homeostase das células-tronco hematopoéticas; e é composto por uma mistura heterogênea de células, dentre elas as células-tronco mesenquimais que expressam moléculas que controlam algumas funções das células-tronco hematopoéticas. De acordo com estas observações, este trabalho investiga o papel do envelhecimento das células-tronco mesenquimais no processo de autorrenovação, multipotência e diferenciação das células-tronco hematopoéticas. Neste trabalho, avaliamos a percentagem de células-tronco hematopoéticas Lin-CD34+ e subpopulações em co-cultura com células-tronco mesenquimais derivadas de medula óssea de diferentes idades, bem como sua capacidade de autorrenovação, diferenciação, secreção da quimiocina CXCL-12 e a expressão do receptor CXCR-4. Nossos resultados mostraram diferenças significativas nos parâmetros fenotípicos e funcionais das células-tronco hematopoéticas co-cultivadas com células-tronco mesenquimais de doadores idosos. Estes dados sugerem que o envelhecimento das células-tronco mesenquimais podem influenciar na homeostase do microambiente medular / Certainly, aging is one of the best identified features of the human biology, and is also the least understood. This is largely attributed to the fact that aging is gradual and fundamentally complex, due to all modifications in the physiological and phenotypic aspects occurred during the age advancing. One of the most striking features of aging is the decreased ability to maintain homeostasis and tissue repair. Consistent with those findings, many of the pathophysiological conditions affecting aging, such as anemia, dysplasia, leukemia and anemia suggest an imbalance between cell losses and the ability to self-renew or differentiation. The decline in homeostatic maintenance and regenerative potential of tissues during aging has been associated with changes in stem cells. Increasing evidences point to the stem cells as major accountable for the aging pathophysiology in several tissues. Thus, studies in mammals comprise a careful evaluation of mechanisms connected to stem cells. The increasing age is accompanied by many pathophysiological changes in the hematopoietic system wherein the etiology suggests loss of homeostatic control and a possible involvement of stem and progenitor cells. The clinically relevant changes are related to adaptive immune system diminished competence, the increase of myeloid diseases including leukemia and the onset of anemia in the elderly. The hematopoietic stem cell microenvironment is located in the bone marrow and is divided in two domains: the endosteal niche near to the bone surface and vascular niche associated with the sinusoidal endothelium; the niche consist of several heterogeneous cells types, among them, the mesenchymal stem cells. The mesenchymal stem cells express molecules that control hematopoietic stem cells functions. Therefore, this study investigates the role of mesenchymal stem cells aging in the self-renewal, multipotency and differentiation of hematopoietic stem cells. This study evaluated the percentage of hematopoietic stem cell Lin-CD34+ and subpopulations in co-culture with mesenchymal stem cell bone marrow-derived from donors with different ages, their ability of self-renewal, differentiation, secretion of chemokine CXCL-12 and expression of the CXCR-4 receptor. Our results suggest that the mesenchymal stem cells aging can affect the bone marrow niche homeostasis
496

Uso intravítreo de fração mononuclear da medula óssea (FMMO) contendo células CD34+ em pacientes portadores de degeneração hereditária da retina - retinose pigmentar (RP) / Intravitreal use of bone marrow mononuclear fraction (BMMF) containing CD34+ cells in patients with hereditary retinal degeneration - retinitis pigmentosa (RP)

Arcieri, Rafael Saran 25 May 2018 (has links)
Introdução: A Retinose Pigmentar (RP) é uma doença hereditária da retina, caracterizada por perda da função visual, principalmente devido à degeneração dos fotorreceptores (bastonetes e cones). Objetivo: Avaliar os efeitos de uma única injeção intravítrea de fração mononuclear de células da medula óssea (FMMO) CD34+ em pacientes portadores de RP. Métodos: Ensaio clínico aberto, não randomizado, prospectivo, observador mascarado, no qual 20 pacientes, portadores de RP, com boa fixação ao exame de campo visual, foram incluídos. Única injeção intravítrea (IIV) de FMMO foi aplicada em apenas um dos olhos de cada paciente, enquanto que os olhos contralaterais serviram como controle e foram submetidos à injeção simulada. As avaliações incluíram: melhor acuidade visual corrigida (MAVC); campo visual estático - estratégia 30-2 (Octopus 900); microperimetria (MAIA - Center Vue) para avaliar estabilidade de fixação e sensibilidade macular; eletrorretinografia de campo total (ERG) e multifocal (mfERG) - padrão da ISCEV usando aparelho Espion E2 (Diagnosys LLC) e tomografia de coerência óptica (OCT). Os exames foram realizados antes da injeção e 4, 16, 32 e 48 semanas após. Resultados: Não houve diferença significativa na MAVC durante o seguimento. A diferença entre MAVC medida após 48 semanas e a basal foi de -0,04 ? 0,02 logMAR nos olhos tratados frente a -0,03 ? 0,01 logMAR nos controles (p=0,3898). A melhora da sensibilidade macular foi discretamente maior nos olhos com FMMO: 1,0 ? 0,5 dB do que nos olhos contralaterais: 0,2 ? 0,5 dB, mas sem significância estatística (p=0,0569). Não se observou mudança na estabilidade de fixação. A perda de desvio médio (MD) do campo visual dos olhos tratados (0,33 ? 0,70 dB) foi discretamente menor do que nos olhos controle (1,12 ? 0,58 dB) (p=0,0761). Nenhuma diferença significativa foi observada nas amplitudes e latências das respostas eletrorretinográficas durante o período avaliado. Não se verificou nenhuma complicação e nem efeito colateral após a injeção. Conclusão: A aplicação intravítrea de FMMO contendo células CD34+ mostrou-se segura em pacientes com RP. Observou-se, ainda, discreta melhora na sensibilidade macular, mas esta não foi significativa estatisticamente. Estudos futuros são necessários para esclarecer o potencial uso dessas células em distrofias retinianas. / Introduction: Retinitis pigmentosa (RP) is a hereditary disease of the retina, characterized by loss of visual function, mainly due to degeneration of the photoreceptors (rods and cones). Objective: To evaluate the effects of a single intravitreal injection of bone marrow mononuclear fraction (BMMF) containing CD34+ cells in patients with RP. Methods: Open trial, non-randomized, prospective, masked observer, in which 20 patients with RP with good fixation in visual field examination were included. Single intravitreal injection of BMMF was performed in only one eye of each patient, while the contralateral eyes served as control and underwent shaw injection. Evaluations included: best corrected visual acuity (BCVA); static visual field - strategy 30-2 (Octopus 900); microperimetry (MAIA - Center Vue) to evaluate fixation stability and macular sensitivity; full-field (ERG) and multifocal (mfERG) electroretinograms according to the ISCEV using Espion E2 (Diagnosys LLC) and optical coherence tomography (OCT). The exams were performed before the injection and 4, 16, 32 and 48 weeks after. Results: There was no significant difference in BCVA during follow-up. The difference measured in BCVA between 48 weeks and baseline was 0.04 ? 0.02 logMAR in treated eyes versus -0.03 ? 0.01 logMAR in controls (p=0.3898). The improvement in macular sensitivity was slightly higher in BMMF eyes: 1.0 ? 0.5 dB than in contralateral eyes: 0.2 ? 0.5 dB, but without statistical significance (p=0.0569). No change in fixation stability was observed. The mean deviation loss (MD) of the visual field in treated eyes (0.33 ? 0.70 dB) was slightly lower than in the control eyes (1.12 ? 0.58 dB) (p=0.0761). No significant difference was observed evaluating amplitudes and latencies of ERG and mfERG responses during the follow-up. No complications or side effects were observed after the injection. Conclusion: The intravitreal injection of BMMF containing CD34 + cells was shown to be safe in patients with RP. There was still a slight improvement in macular sensitivity, but this was not statistically significant. Future studies are needed to clarify the potential use of these cells in retinal dystrophies.
497

Reconstituição imunológica após transplante autólogo de células-tronco hematopoéticas em pacientes com diabetes mellitus tipo 1 e esclerose múltipla / Immune reconstitution after autologous hematopoietic stem cell transplantation in type 1 diabetes and multiple sclerosis patients.

Arruda, Lucas Coelho Marliére 16 August 2013 (has links)
Ensaios clinicos tem demonstrado que a imunossupressao em altas doses (IAD) seguida de transplante autologo de celulas tronco hematopoeticas (TACTH) e capaz de suprimir a atividade inflamatoria em pacientes com doencas autoimunes (DAIs) e induzir remissoes clinicas prolongadas nesses pacientes, porem os mecanismos de acao do TACTH ainda nao estao bem esclarecidos. O racional dessa terapia baseia-se na eliminacao das celulas autorreativas pela IAD e na reconstituicao de um sistema imunologico novo e tolerante apos o transplante a partir dos precursores hematopoeticos. O objetivo deste trabalho foi avaliar a reconstituicao imunologica em pacientes com diabetes mellitus tipo 1 (DM1, N=21) e pacientes com esclerose multipla (EM, N=37) sequencialmente apos o TACTH, e correlacionar os dados imunologicos com a resposta clinica dos pacientes ao transplante. Os pacientes com EM e DM1 foram divididos em dois grupos com base na resposta clinica apos o transplante: respondedores (EM-R; N=22) e nao-respondedores (EM-NR; N=15); livres de insulina por periodo maior ou igual a 3 anos (DM13 anos; N=11) e livres de insulina por periodo menor que 3 anos (DM1<3 anos; n=10); e acompanhados clinica e imunofenotipicamente por seis anos. Em relacao ao periodo pre-transplante, todos os grupos de pacientes com DM1 e EM apresentaram: 1, diminuicao do numero absoluto de celulas T CD3+ praticamente em todos os periodos pos-transplante avaliados, indicando uma intensa linfopenia decorrente da IAD; 2, aumento acentuado do numero de linfocitos T CD8+ e a diminuicao dos linfocitos T CD4+, resultando na inversao da razao CD4:CD8 durante todo o seguimento pos-transplante avaliado; 3, aumento significativo no primeiro ano apos o transplante das subpopulacoes de celulas T CD8+ de memoria central CD27+CD45RO+ e memoria efetora CD27- CD45RO+; 4, normalizacao dos numeros de linfocitos T CD4+ e CD8+ naive CD27+CD45RO- somente cinco anos apos o transplante, enquanto o numero de celulas T CD4+CD45RA+CD31+ recem- emigrantes do timo manteve-se abaixo dos valores pre-transplante durante todo o periodo avaliado, demonstrando que durante os seis anos de seguimento apos a IAD/TACTH predominaram mecanismos timo-independentes de reconstituicao imunologica; 5, normalizacao dos numeros de linfocitos B CD19+ entre dois a tres meses pos-transplante. O grupo de pacientes com DM1 que obteve melhor resposta clinica apos o tratamento com IAD/TACTH (DM13anos) apresentou, em comparacao ao periodo pre-transplante, numero diminuido de celulas T CD3+ (linfopenia) em varios periodos pos-transplante, numero aumentado de celulas T CD8+CD28- supressoras no primeiro ano pos-transplante principalmente, numero diminuido de celulas T CD4+ de memoria efetora nos periodos 2 a 9 meses pos-transplante e numero aumentado de celulas T reguladoras CD4+CD25hiFOXP3+ pos-transplante. O grupo de pacientes com EM com melhor resposta clinica apos o tratamento com IAD/TACTH (EM-R) apresentou, em comparacao ao periodo pre-transplante, numero diminuido de celulas T CD3+ (linfopenia) em varios periodos pos-transplante e numeros aumentados de celulas T reguladoras CD4+CD25hiFOXP3+ e CD8+CD28- supressoras nos primeiros tres anos pos-transplante. Vale ressaltar que os pacientes com DM1 e EM que apresentaram melhor resposta clinica permaneceram linfopenicos por maiores periodos de tempo apos o transplante. Desse modo, esse estudo revelou que a resposta terapeutica dos pacientes com DM1 e EM ao TACTH depende de uma linfopenia persistente, alem do aumento de celulas T reguladoras e supressoras e diminuicao de celulas T CD4+ de memoria apos o transplante. / Clinical trials have shown that high-dose immunosuppression (HDI) followed by autologous hematopoietic stem cell transplantation (AHSCT) is able to suppress the inflammatory activity in patients with autoimmune diseases (AID) and induce prolonged clinical remissions in these patients, but the mechanisms of action of AHSCT are still not well understood. The rationale of this therapy is based on the elimination of autoreactive cells by HDI and on the reconstitution of a new tolerant immune system after transplantation from hematopoietic precursors. The aim of this study was to evaluate the immune reconstitution in patients with type 1 diabetes mellitus (T1D, N=21) and patients with multiple sclerosis (MS, N=37) sequentially after the AHSCT, and correlate the immunological data with the clinical response of these patients to the transplant. Patients with MS and T1D were divided into two groups based on clinical response following transplantation: response (MS-R, N=22) and non-response (MS-NR, N=15); insulin-free for a period longer or equal to 3 years (T1D3 years, n=11) and insulin-free for less than 3 years (T1D<3 years, n=10); and accompanied clinical and immunophenotypically by six years. Regarding the pre-transplant period, all groups of patients with T1D and MS showed: 1, decreased absolute number of CD3+ T cells in virtually all post-transplant periods evaluated, indicating an intense lymphopenia resulting from HDI; 2, sharp increase in the number of CD8+ T lymphocytes and decreased CD4+ T lymphocytes, resulting in inversion of CD4:CD8 ratio throughout the follow-up post-transplant evaluation; 3, a significant increase, in the first year after transplantation, of CD8+ T central memory CD27+CD45RO+ and effector memory CD27-CD45O+ cell subpopulations; 4, normalization of CD4+ and CD8+ T naive CD27+CD45RO- lymphocytes numbers only five years after transplantation, whereas the number of CD4+CD45RA+CD31+ T cells newly emigrants from the thymus remained below the values pre- transplant during the study period, showing that during the six years of follow-up after the HDI/AHSCT mechanisms thymus-independent immune reconstitution were predominant; 5, normalization of CD19+ B lymphocytes numbers in two to three months post-transplant. The group of patients with DM1 that had the best clinical response after treatment with IAD/AHSCT (T1D 3years) showed, in comparison with the pre-transplant period, decreased number of CD3+ T cells (lymphopenia) at various times after transplantation, increased CD8+CD28- suppressor T cells numbers in the first year post-transplant, decreased number of CD4+ effector memory in periods of 2 and 9 months post-transplant and increased number of CD4+CD25hiFOXP3+ regulatory T cells after transplantation. The group of MS patients with better clinical response after treatment with IAD/AHSCT (MS-R) showed, in comparison to the pre-transplant period, decreased number of CD3+ T cells (lymphopenia) at various times after transplantation and increased numbers of CD4+CD25hiFOXP3+ regulatory Tcell and CD8+CD28- suppressor in the first three years post- transplant. It is noteworthy that patients with T1D and MS which showed better clinical response remained lymphopenic for longer periods of time after transplantation. Thus, this study revealed that the therapeutic response of patients with T1D and MS depend on a AHSCT to persistent lymphopenia, and increased regulatory and suppressor T cells and decreased number of CD4+ effector memory after transplantation.
498

Avaliação funcional de pacientes com esclerose sistêmica submetidos ao transplante autólogo de células-tronco hematopoéticas / Functional evaluation of systemic sclerosis patients after autologous hematopoietic stem cell transplantation

Pereira, Karla Ribeiro Costa 13 December 2017 (has links)
Esclerose sistêmica (ES) é uma doença autoimune caracterizada por fibrose cutânea associada a envolvimento visceral, levando a diminuição da capacidade física, limitação no desempenho das atividades de vida diária e prejuízo na qualidade de vida. O transplante autólogo de células-tronco hematopoéticas (TACTH) vem sendo estudado como uma alternativa terapêutica para pacientes com ES, proporcionando melhora do acometimento cutâneo e ao menos estabilização do quadro pulmonar. O objetivo deste estudo é avaliar o impacto do TACTH no acometimento da pele, capacidade funcional e qualidade de vida em pacientes com ES. Trata-se de um estudo longitudinal e prospectivo, conduzido no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto. Os pacientes com ES submetidos ao TACTH foram avaliados inicialmente, e reavaliados 6 e 12 meses após o tratamento. A avaliação consistiu dos seguintes itens: acometimento da pele, avaliado pelo escore modificado de Rodnan (mRSS), função pulmonar (capacidade vital forçada, CVF e capacidade de difusão do monóxido de carbono, DLCO), força muscular respiratória (pressão inspiratória máxima - PImáx, e pressão expiratória máxima - PEmáx), mobilidade tóraco-abdominal pela cirtometria, avaliação funcional dos membros superiores (força de preensão das mãos, amplitude de movimento pela goniometria, distância finger-to-palm - FTP, questionários Disabilities of the arm, shoulder and hands - DASH, e Cochin hand functional scale - CHFS), abertura oral, teste de caminhada de seis minutos (TC6) e questionário de qualidade de vida Medical Outcomes Study - 36 item short-form (SF-36). Vinte e sete pacientes com ES foram avaliados antes e 6 meses após o transplante, e 22 desses pacientes foram adicionalmente avaliados aos 12 meses pós-transplante. Quando comparadas com os valores iniciais, pré-transplante, observou-se melhora significativa das variáveis mRSS, PImáx, PEmáx, cirtometria, força de preensão das mãos dominante e não-dominante, amplitudes de movimento articulares, FTP das mãos dominante e não-dominante, DASH, CHFS, abertura oral, distância percorrida no TC6, domínios capacidade funcional, aspectos físicos, dor, estado geral de saúde, vitalidade, aspectos sociais e saúde mental do SF-36 e medidas sumárias de componentes físico e mental do SF-36, após o transplante. Houve estabilização da função pulmonar após o transplante. Houve correlação significativa entre o mRSS e medidas de amplitude de movimento de punho, entre a capacidade física avaliada pelo TC6 e o componente físico do SF-36 e entre o questionário DASH e o componente físico do SF-36. Em conclusão, o TACTH promove melhora significativa do acometimento da pele, da capacidade funcional e da qualidade de vida de pacientes com ES, até pelo menos 1 ano de seguimento após o transplante. Embora a função pulmonar tenha apenas se estabilizado, os pacientes apresentaram significativa melhora da capacidade física. / Systemic sclerosis (SSc) is an autoimune disease characterized by skin fibrosis, associated with internal organ involvement, leading to decreased physical capacity, limitations in daily life activities and impairment of quality of life. Autologous hematopoietic stem cell transplantation (AHSCT) has been studied as an alternative treatment for patients with severe SSc, and promotes improvement of skin involvement and, at least, pulmonary function stabilization. The aim of this study is to evaluate the impact of AHSCT in skin involvement, functional capacity and quality of life in SSc patients. This is a prospective and longitudinal study, conducted at the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, University of São Paulo. SSc patients were evaluated before, and 6 and 12 months after transplant for skin involvement by modified Rodnan skin score (mRSS), pulmonary function (forced vital capacity, FVC, carbon monoxide diffusion capacity, DLCO), respiratory muscle strength (maximal inspiratory pressure - MIP, and maximal expiratory pressure - MEP), thoracoabdominal mobility by cirtometry, functional evaluation of upper limbs (hand grip strength, range of motion by goniometry, finger-to-palm distance - FTP, Disabilities of the arm, shoulder and hands questionnaire - DASH, and Cochin hand functional scale questionnaire - CHFS), mouth opening, six-minute walk test (6MWT) and quality of life by the Medical Outcomes Study - 36 item short-form (SF-36). Twenty-seven patients were evaluated before and at 6 months after transplant, 22 of which were additionally evaluated at 12 months after transplant. When compared to pre-transplant evaluations, patients presented significant improvement of mRSS, MIP, MEP, cirtometry, hand grip strength, range of motion measurement, FTP distance, DASH, COCHIN, mouth opening, distance in 6MWT, physical functioning, role-physical, bodily pain, general health, vitality, social functioning and mental health domains of SF-36, and summary measures of the SF-36 Physical Component score and Mental Component score after AHSCT. The pulmonary function stabilized after transplant. Significant correlations were observed between skin involvement and range of motion measures, physical capacity and quality of life, and DASH and quality of life. In conclusion, AHSCT significantly improves the functional status of SSc patients in the first year of follow-up. Although the pulmonary function remained stable after AHSCT, there was significant increase in the physical capacity of patients.
499

Análise dos fatores que influenciam o desenvolvimento da mucosite oral em transplante de células-tronco hematopoiéticas autólogo / Analysis of factors that influence the oral mucositis development in autologous stem cell transplantation

Mello, Walmyr Ribeiro de 22 September 2016 (has links)
A mucosite é um efeito grave e dose-limitante do tratamento antineoplásico, cujas lesões ulceradas apresentam grande impacto na morbidade e mortalidade dos pacientes, por apresentar dor, restrição alimentar e servindo como porta de entrada para infecções originadas da mucosa bucal, com incidência variável de acordo com a doença de base, idade, condição de saúde bucal, dose e frequência da quimioterapia. A ocorrência de mucosite oral é frequente nos pacientes que receberam altas doses de quimioterapia seguidas de transplante autólogo de células tronco hematopoiéticas. O objetivo deste estudo foi analisar os fatores que influenciam o desenvolvimento da mucosite oral. Foi realizada uma análise retrospectiva em 413 prontuários de pacientes consecutivos submetidos ao transplante autólogo de células tronco hematopoiéticas e os dados coletados incluíram dados demográficos (sexo, idade, doença de base), dados do TCTH (tipo de transplante, regime de condicionamento) e incidência de mucosite oral. Os resultados deste estudo mostraram que a incidência de mucosite foi maior em pacientes do sexo masculino e nos pacientes do sexo feminino com idade média de 29 anos, nos pacientes submetidos ao regime de condicionamento BU/MEL e naqueles pacientes portadores de LMA. Os resultados deste estudo permitiram concluir que a incidência de mucosite oral na casuística analisada foi maior nos pacientes do sexo masculino; nas mulheres jovens quando analisados sexo e idade separadamente, nos pacientes portadores de LMA e naqueles submetidos ao regime de condicionamento BU/MEL / Oral mucositis remains as a serious and dose-limiting side-effect of antineoplastic treatment and ulcerated lesions lead to a great impact on morbidity and mortality of patients due to pain, food restriction and serving as a gateway to originate infections of the oral mucosa patients. The incidence of oral mucositis remains uncertain and it is variable according to the underlying disease, age, oral health condition, dose and frequency of chemotherapy. The incidence of oral mucositis is high in patients receiving high-dose chemotherapy followed by autologous transplantation of hematopoietic stem cells. The aim of this study was to analyze the factors that influence the development of oral mucositis. a retrospective analysis of 413 medical records of consecutive patients undergoing autologous hematopoietic stem cell transplantation. Data collected included demographic data was performed (sex, age, underlying disease), HSCT data (type of transplant conditioning regimen) and incidence oral mucositis. The results of this study showed that the incidence of mucositis was higher in male patients and female patients with a mean age of 29 years, in patients undergoing conditioning regimen comprises BU / MEL and in those patients with AML. The results of this study showed that the incidence of oral mucositis in the analyzed sample was higher in males; in young women when analyzed separately sex and age, in patients with AML and those submitted to the BU / MEL conditioning regimen
500

Nível sérico de ciclosporina no transplante de células-tronco hematopoéticas: influência do intervalo de tempo entre a interrupção da infusão e a obtenção das amostras de sangue considerando a via de coleta e o volume de descarte -ensaio clínico randomizado / Cyclosporine serum level in hematopoietic stem cell transplantation: influence of time interval between discontinuation of the infusion and collection of blood samples considering collection line and volume of discard - a randomized clinical trial

Garbin, Livia Maria 18 March 2014 (has links)
Há evidências de que a ciclosporina, imunossupressor utilizado nos transplantes de células- tronco hematopoéticas, impregna nos cateteres de silicone quando os mesmos são utilizados para a sua infusão; podendo a coleta de amostras para dosagem sérica do medicamento por essa via resultar em níveis falsamente elevados. Apesar de já existirem dados comprovando a possibilidade de se coletar as amostras da via do cateter venoso central não utilizada para a infusão, há escassez de estudos e também controvérsias quanto ao melhor momento para realizar o procedimento, assim como divergências quanto ao volume de sangue ideal a ser descartado. Esse ensaio clínico controlado randomizado teve como objetivo verificar o efeito do tempo transcorrido entre a interrupção da infusão de ciclosporina e a coleta das amostras na dosagem sérica do medicamento, em relação à via utilizada para a coleta e ao volume de descarte. Os sujeitos foram aleatorizados em dois grupos. No grupo A, a coleta das amostras em acesso venoso periférico, via do cateter utilizada para a infusão da ciclosporina e via não utilizada para infusão foi realizada imediatamente após a interrupção da infusão do medicamento, sendo que na última a coleta foi realizada após descarte de 5 mL e de 10 mL de sangue. No grupo B os mesmos procedimentos foram realizados, porém cinco minutos depois da interrupção. Participaram 32 sujeitos adultos, a maioria do sexo masculino (68,75%), portadores de leucemia (59,37%), com doadores aparentados (84,37%) e histocompatibilidade total (90,62%). A coleta realizada previamente ao início da infusão da ciclosporina atestou ausência desta no sangue e impregnada nos cateteres. As demais foram realizadas nos 32 sujeitos depois de 24 horas do início da infusão; em 12 do grupo A e 16 do grupo B sete dias depois; e em nove do grupo A e 13 do B 14 dias após iniciado o uso do medicamento. O principal motivo que levou à interrupção da coleta foi a transição da ciclosporina para via oral (71,87%). Inicialmente, nas análises intra sujeitos, a diferença entre a dosagem sérica obtida na via do cateter utilizada para a infusão da ciclosporina e as outras vias foi significativa (p < 0,001), enquanto entre o acesso venoso periférico e via não utilizada para a infusão, independente do volume de descarte, não houve diferença (p > 0,05). Quando realizadas as comparações entre os grupos, não foram observadas diferenças (p > 0,05) quanto à influência do tempo transcorrido entre a interrupção da infusão e a coleta das amostras de sangue, independente da via de coleta utilizada e do volume descartado. Conclui-se que a via do cateter não utilizada para infusão da ciclosporina é segura para ser utilizada na coleta das amostras para dosagem sérica desse medicamento; e o procedimento pode ser realizado imediatamente após a interrupção da infusão, desde que empregada a técnica adequada com descarte de 5 mL de sangue. Assim evita-se que o sujeito, já fragilizado e submetido a um tratamento complexo, seja exposto a mais um procedimento doloroso e associado ao estresse que é punção venosa periférica / There is evidence that cyclosporine, an immunosuppressant used in hematopoietic stem cell transplantation, impregnate in silicone catheters when they are used for its infusion; and the sample collection for serum levels of medication through this line may result in falsely elevated levels. Although there are data demonstrating the possibility to collect samples through the line of the central venous catheter not used for the infusion, there are few studies and also controversies regarding the best time to perform the procedure, as well as disagreement about the optimal volume of blood to be discarded. This randomized controlled trial aimed to verify the effect of time elapsed between discontinuation of the infusion and serum sample collection in relation to the line used for collection and volume of discard. The subjects were randomized into two groups. In group A, samples collected from a peripheral venous access, through catheter line used for cyclosporine infusion and catheter line not used for cyclosporine infusion was performed immediately after discontinuation of the drug infusion, and the last collection was performed after discarding 5ml and 10ml of blood. In group B, the same procedures were done, but five minutes after the interruption. The participants were 32 adults, most males (68,75%), with leukemia (59,37%), with related donors (84,37%), and total histocompatibility (90,62%). The collection performed prior to the start of cyclosporine infusion attested absence of cyclosporine in blood and presence of it in catheters. The others were performed in 32 subjects after 24 hours prior the start of infusion; in 12 of group A and 16 of group B after seven days; and in 9 of group A and 13 of B fourteen days after starting the medication. The main reason that led to discontinuation of the collection was the switch of cyclosporine to oral administration (71,87%). Initially, in the intra-subject analysis, the difference between the serum levels obtained in the line used for cyclosporine infusion of and other lines was significant (p < 0,001), while there was no difference between the peripheral venous access and the line not used for infusion, independently of the volume of discard (p > 0,05). When performed comparisons between groups, no differences were observed (p > 0,05) in the influence of time elapsed between discontinuation of the infusion and collection of blood samples, regardless the line used for collection and volume of discard. It is concluded that the catheter line not used for infusion of cyclosporine seems to be safe for use in serum samples collection of this medication; and the procedure can be performed immediately after discontinuation of the infusion, since used the technique with adequate discard of 5ml of blood. This avoids that the subject, already weakened and subordinated to a complex treatment, be exposed to a painful and stressful procedure such as peripheral venipuncture

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