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GENETIC REGULATION OF HEMATOPOIETIC STEM CELL AGINGOakley, Erin J. 01 January 2008 (has links)
It is well documented that both quantitative and qualitative changes in the murine hematopoietic stem cell (HSC) population occur with age. In mice, the effect of aging on stem cells is highly strain-specific, thus suggesting genetic regulation plays a role in HSC aging. In C57BL/6 (B6) mice, the HSC population steadily increases with age, whereas in DBA/2 (D2) mice, this population declines. Our lab has previously mapped a quantitative trait locus (QTL) to murine chromosome 2 that is associated with the variation in frequency of HSCs between aged B6 and D2 mice. In these dissertation studies, I first aim to characterize the congenic mouse model which was generated by introgressing D2 alleles in the QTL onto a B6 background. Using a surrogate assay to mimic aging, I analyzed the cell cycle, apoptotic and self-renewal capabilities of congenic and B6 HSCs and show that D2 alleles in the QTL affect the apoptotic and selfrenewal capabilities of HSCs. In the second aim of these studies, I used oligonucleotide arrays to compare the differential expression of B6 and congenic cells using a population enriched for primitive stem and progenitor cells. Extensive analysis of the expression arrays pointed to two strong candidates, the genes encoding Retinoblastoma like protein 1 (p107) and Sorting nexin 5 (Snx5). B6 alleles were associated with increased p107 and Snx5 expression in old HSCs therefore both genes were hypothesized to be positive regulators of stem cell number in aged mice. Finally, in the third aim of these studies, I show that the individual overexpression of p107 and Snx5 in congeic HSCs increases day35 cobblestone area forming cell (CAFC) numbers, therefore confirming their roles as positive regulators of HSC number in vitro. These studies uncover novel roles for p107 and Snx5 in the regulation of HSC numbers and provide additional clues in the complex regulation of HSC aging.
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Consequences of Shb Deficiency on Hematopoietic Cell FunctionGustafsson, Karin January 2013 (has links)
The adaptor protein Shb has been implicated in the signaling of several tyrosine kinase receptors and previous studies have suggested a role for Shb in the signal transduction of T cells. Shb associates with the T cell receptor (TCR) and partakes in the signal propagation of activated T lymphocytes. In order to explore Shb’s influence on TCR signaling in vivo, T cell development and function was studied in a Shb knockout mouse. The loss of Shb led to aberrant TCR signaling in both thymocytes and peripheral CD4+ TH cells, with elevated basal phosphorylation of key components in the signal cascade. Shb was found to be dispensable for thymocyte development, but its absence resulted in a TH2 bias in in vitro stimulated peripheral CD4+ TH cells. As imbalances in TH2 responses are linked to allergic diseases, we further explored Shb’s role in immune regulation in a mouse model of atopic dermatitis. Shb knockout mice exhibit more aggravated signs of atopic dermatitis, including increased immune cell recruitment to the affected areas and elevated mRNA levels of typical TH2 cytokines. The effect of Shb on hematopoiesis in general was determined by examining populations of long-term hematopoietic stem cells (LT-HSCs) and hematopoietic progenitor cells in bone marrow of Shb knockout and wild type mice. Shb deficient bone marrow was found to contain significantly fewer relative numbers of LT-HSCs due to a proliferative defect. The reduced cell cycle activity of Shb LT-HSCs could further be linked to an abnormal regulation of the focal adhesion kinase/Rac1/p21-activated kinase pathway. Since alterations in LT-HSC proliferative abilities may have implications for leukemia development, BCR-Abl induced myeloid neoplasia was investigated in the absence of Shb. Shb deficiency confers a more aggressive progression of BCR-Abl induced myeloid neoplasia characterized by an increased peripheral blood neutrophilia and a deregulated cytokine profile. In addition, focal adhesion kinase and STAT3 signaling is hyperactivated in Shb knockout leukemic cells. In conclusion, Shb appears to be a multifunctional signaling mediator that controls several responses in hematopoietic cells, under homeostatic as well as disease conditions.
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Régulation transcriptionnelle du gène RHOH et potentielles cibles de la protéine dans différents modèles hématopoïétiques normaux et leucémiques / Transcriptional regulation of RHOH gene and potential targets of RhoH protein in different normal and leukemic hematopoietic cellsDelestré, Laure 17 December 2010 (has links)
RhoH est une petite protéine G de la famille Rho constitutivement activée. Cette protéine, exclusivement exprimée dans les cellules hématopoïétiques, intervient dans le développement du système immunitaire. Elle régule la croissance des cellules souches et des progéniteurs hématopoïétiques, la différenciation des lymphocytes T et la signalisation des récepteurs TCR, BCR et FcεRI présents respectivement à la surface des cellules T, B et des mastocytes. La dérégulation de l’expression du gène RHOH est un facteur de progression tumorale dans certaines leucémies. En effet, l’augmentation de son expression dans la Leucémie Lymphoïde Chronique (LLC) et sa répression dans la leucémie à tricholeucocytes (HCL) sont des évènements impliqués dans la progression de ces maladies. La LLC et l’HCL sont deux pathologies affectant des lymphocytes B matures mais, pour cette dernière, les cellules présentent un état de différenciation plus avancé. RhoH module donc différemment les processus de prolifération, de migration et de survie cellulaires selon le stade de maturation des cellules, suggérant que son expression soit finement régulée dans les cellules hématopoïétiques. Au laboratoire, notre équipe a mis en évidence la répression de RHOH dans l’HCL, responsable de la progression de cette maladie. Cette expression anormale est le résultat d’une diminution des transcrits RHOH initiés en amont de l’exon 4. Le même phénomène a également été observé dans la leucémie T de l’adulte (ATL). L’HCL et l’ATL sont deux maladies caractérisées par une prolifération anormale de cellules matures activées de type B (HCL) ou de type T (ATL). Nous avons donc projeté de comprendre les mécanismes moléculaires intervenant dans la régulation physiologique du gène RHOH au cours de l’activation lymphocytaire B et T ; puis de mettre en évidence les évènements responsables de la répression de RHOH dans l’HCL et l’ATL. Notre objectif serait d’y restaurer l’expression de RHOH et ainsi d’essayer de contrecarrer le phénotype leucémique, ceci dans le but de proposer de potentielles nouvelles cibles thérapeutiques dans ces deux leucémies, dont les traitements sont soit inefficaces (ATL), soit satisfaisants mais associés à des taux de rechutes assez élevés (HCL). Notre projet s’est tout d’abord orienté sur l’étude de la régulation normale du gène RHOH dans les cellules B et T. Nos résultats ont permis de montrer que l’expression du gène RHOH est principalement due à l’activité du promoteur P3 dans les lymphocytes B et T normaux et dans des lignées cellulaires lymphoïdes. Dans les lignées lymphoïdes B, le promoteur P3 a été caractérisé et correspond à la séquence -236/+67, en regard du site d’initiation de la transcription. Nous avons observé une augmentation de son activité suite à l’activation de ces cellules par un analogue du diacylglycérol (DAG), suggérant que des facteurs de transcription comme AP1, complexe formé des membres des familles Jun et Fos, sont impliqués dans la régulation du gène RHOH dans des lignées cellulaires lymphoïdes B. Nos résultats ont également permis de mettre en évidence : d’une part, la fixation de JunD sur le promoteur P3, par immunoprécipitation de la chromatine et son rôle de régulateur négatif dans la transcription de RHOH ; d’autre part, l’importance des membres de la famille Fos dans l’expression de ce gène, dans la lignée lymphoïde B Raji. Dans les lymphocytes T, l’activation des cellules par des anticorps anti-CD3 et anti-CD28 a permis d’observer une variation biphasique de l’expression des transcrits RHOH initiés en amont de l’exon 4, au niveau du promoteur P3 : tout d’abord, une forte augmentation du taux des ARN messagers, reproduite par l’utilisation d’un ionophore pour le calcium, suivie d’une répression, mimée par l’analogue du DAG. / The hematopoietic GTPase RhoH is an atypical family member of the Rho GTPases as it is constitutively active and not regulated through the classical cycling between GTP- and GDP-bound state. A number of studies investigated the role of RhoH in hematopoietic cells. RhoH is associated with regulation of proliferation of hematopoietic stem and progenitors. This protein exhibits essential functions in thymocyte development and TCR, BCR, FcεRI signaling in T, B and mast cells, respectively. Recently, a report provided evidence implicating RhoH overexpression in the initiation and progression of Chronic Lymphocytic Leukemia (CLL); on the other hand, RhoH underexpression has been implicated in the progression of Hairy Cell Leukemia (HCL). Most data indicate that RhoH is an important regulatory molecule with antagonistic functions in proliferation, adhesion or migration in hematopoietic cells and therefore must be accurately regulated. Previous experiments from our laboratory reported that HCL is characterized by abnormal underexpression of RhoH, corresponding to a decreased level of RHOH mRNA initiated upstream of exon 4. Reconstitution of RhoH expression reduced proliferation, adhesion and migration that is central in HCL pathogenesis. Transcriptional repression of this gene was also observed in another leukemia, Adult T cell Leukemia (ATL). Aimed at identifying new therapeutic targets to combat HCL and ATL, we wanted to examine molecular mechanisms implicated in RhoH underexpression in both diseases. HCL and ATL are chronic lymphoproliferative disorders characterized by proliferation of mature cells with memory B cell or T-helper cell phenotype, respectively. In the first part of our work, we wanted to investigate molecular mechanisms mediating normal RhoH expression in activated B and T cells, as well as induced pathways; in the second part, we tempted to identify transcription factors implicated in RhoH repression in HCL and ATL. Firstly, our work has focused onto physiological expression of RHOH gene in B and T cells. We showed that RHOH gene expression observed in these cells was mostly due to transcriptional activity of P3 promoter, upstream of RHOH exon 4. The promoter was isolated spanning nucleotides -236/+67 relative to the transcription start site, in B cells. B cells stimulation by PMA (Phorbol-12-Myristate-13-Acétate) induced an increase of P3 promoter activity. PMA is a DiacylGlycerol (DAG) analogous. This result suggested that transcription factors related to DAG pathway stimulation, like AP1 (Activator Protein 1), could be responsible for RHOH expression in B cells. We could show that the Jun family member JunD is able to bind to endogenous P3 promoter and can act as a repressor of RHOH expression in a B cell line, Raji. Other Jun family members seemed not to be implicated in this regulation. We also reported that Fos family members are important in RHOH expression. Our results suggest that the transcription factor AP1 could regulate this process in B cells. T cell activation by antibodies directed against CD3 and CD28 induced biphasic kinetics of expression of RHOH mRNA initiated upstream of exon 4. We observed a high increase of RHOH transcript level, mimicked by use of ionomycin, followed by an important decrease, mimicked by use of PMA. RHOH P3 promoter was isolated in a T cell line, Jurkat, then we investigated putative binding sites for transcription factors, which could be implicated in this biphasic event in T cells. Our preliminary results have shown that some potential binding sites for transcription factors related to calcium pathway and inducing RHOH expression are present between nucleotides -236 and -201; also sites for transcription factors induced by DAG pathway and repressing this gene are present between nucleotides -583 and -380.
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Effects of High Vs. Reduced‐Dose Melphalan For Autologous Bone Marrow Transplantation in Multiple Myeloma On Pulmonary Function: A Longitudinal StudyNikolich‐Zugich, Tijana 12 May 2017 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Bone marrow transplants (BMT, also hematopoietic stem cell transplants or HSCT/SCT) are one of the greatest medical achievements of the 20th century. They offer a treatment for a host of malignant and nonmalignant hematopoietic disorders, genetic diseases and solid tumors that could otherwise be fatal. Studies have found that 60% of patients undergoing BMT develop pulmonary complications (PC), and 1/3 of those require intensive care after transplantation. Despite the potential pneumotoxicity of induction agents, to date there have been no longitudinal studies following pulmonary function in this high‐risk patient population. This study reviewed patient who underwent autogeneic bone marrow transplant for multiple myeloma at Banner University Medical Center – Tucson (formerly University of Arizona Health Network) from January 1, 2003 through December 31, 2013. Pretransplant evaluatin and pulmonary function testing data were obtained and stratified between high dose (standard) Melphalan (200 mg/ms2) and reduced dose (140 mg/ms2). Statistically significant differences were present between the 2 groups at baseline for DLCO but disappeared at 6 and 12‐month followup, while a statistically significant difference for FEV1/FVC ratio was seen at baseline and 6 months but disappeared at 12‐month follow‐up. There were no statistically significant differences seen with FEV1 between the two groups. Given there is no difference in mortality and relapse outcomes between the groups, the standard of care dosing for Melphalan is not associated with an increase in pulmonary morbidity.
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Distinguishing autocrine and paracrine signals in hematopoietic stem cell culture using a biofunctional microcavity platformMüller, Eike, Wang, Weijia, Qiao, Wenlian, Bornhäuser, Martin, Zandstra, Peter W., Werner, Carsten, Pompe, Tilo 24 August 2016 (has links) (PDF)
Homeostasis of hematopoietic stem cells (HSC) in the mammalian bone marrow stem cell niche is regulated by signals of the local microenvironment. Besides juxtacrine, endocrine and metabolic cues,
paracrine and autocrine signals are involved in controlling quiescence, proliferation and differentiation of HSC with strong implications on expansion and differentiation ex vivo as well as in vivo transplantation.
Towards this aim, a cell culture analysis on a polymer microcavity carrier platform was combined with a partial least square analysis of a mechanistic model of cell proliferation. We could demonstrate the discrimination of specific autocrine and paracrine signals from soluble factors as stimulating and inhibitory effectors in hematopoietic stem and progenitor cell culture. From that we hypothesize autocrine signals
to be predominantly involved in maintaining the quiescent state of HSC in single-cell niches and advocate our analysis platform as an unprecedented option for untangling convoluted signaling mechanisms in complex cell systems being it of juxtacrine, paracrine or autocrine origin.
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Phospholipase A2 Induced Monocyte Chemotaxis to Apoptotic CellsKarikari, Kwasi 01 January 2006 (has links)
Apoptosis is a form of programmed cell death that is essential in such processes as organ and tissue remodeling and maturation of hematopoietic cells. The clearance of apoptotic cells is essential to prevent autoimmune responses to sequestered antigens. This process is mediated by phagocytes of the monocyte lineage. Before phagocytosis can occur, macrophages must be recruited to the apoptotic cells through chemotaxis. Products of the reaction catalyzed by the phospholipases A2 (PLA2) have been shown to induce monocyte chemotaxis either directly or indirectly. Some investigators have implicated a cytosolic calcium-independent PLA2 (iPLA2) in the production of these products during apoptosis. However, a recent report suggests that the secreted group IIa (sPLA2) binds to surfaces of apoptotic cells. The "receptor" for this pool of sPLA2 is the rod domain of vimentin, an intermediate filament protein that is exposed by caspase activity when cells undergo apoptosis. Based on these observations, we hypothesize that the exposure of vimentin on apoptotic cells traps a pool of catalytically active sPLA2 that then generates the bioactive lipids that induce macrophage chemotaxis. In our methods, [3H]-oleate labeled E-coli is used as a substrate for sPLA2 and enzyme activity is quantified by scintillation counting of released radiolabeled oleic acid. Apoptosis is induced with anti-fas (CD-95) on Jurkat cells and monitored through annexin-V binding and propidium iodide(PI) staining followed by flow cytometric analyses. THP-1 monocytes are employed in chemotaxis assay with monocyte chemotactic protein (MCP-1) as a positive control. The preliminary data show equivalent group IIa sPLA2 association with anti-fas treated and control cells, and the enzyme remains catalytically active when bound. In line with the hypothesis, trapped sPLA2 generated soluble molecules that directly or indirectly induced migration of THP-1 monocytes. However, the similar binding effect observed with apoptotic or control cells is surprising and experiments are being planned to determine if the interaction between IIa sPLA2 and apoptotic cells is vimentin dependent.
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Modelo de camundongo imunodeficiente (NSG) para enxertia de células-tronco hematopoéticas / Immunodeficient mouse (NSG) model for hematopoietic stem cell grafting.Boas, Fernanda Lima Vilas 28 February 2019 (has links)
O transplante de células-tronco hematopoéticas (CTHs) é o tipo de terapia celular mais usada atualmente. As células-tronco da medula óssea humana, do sangue periférico mobilizado e do sangue do cordão umbilical (SCU) são as únicas fontes de células utilizadas clinicamente para a recuperação hematopoética, mas elas têm uma disponibilidade limitada e apenas um terço dos pacientes apresentam um doador compatível. Uma fonte alternativa para suprir esta demanda seriam as células hematopoéticas derivadas a partir de células-tronco pluripotentes. Célulastronco embrionárias (CTE) são um tipo de células pulripotentes caracterizadas por sua capacidade ilimitada de autorrenovação e diferenciação em todas as células especializadas do indivíduo adulto. A alta capacidade de diferenciação dessas células em linhagens específicas por métodos de indução in vitro faz delas grandes promessas para o desenvolvimento de novas tecnologias aplicáveis à medicina regenerativa e terapia celular. Entretanto, ainda é necessário determinar se células-tronco hematopoéticas (CTH) geradas a partir de células pluripotentes são funcionais in vivo. Assim, o objetivo desse estudo consistiu no desenvolvimento de um modelo animal para o transplante de células hematopoéticas humanas provenientes de células pluripotentes e utilizamos CTH de sangue de cordão umbilical como controle. Para tanto, realizamos a padronização da dose de irradiação subletal nos camundongos NOD / SCID IL2R ? null (NSG) e utilizamos duas concentrações de células, 1x106 e 0,75x106 de células hematopoéticas diferenciadas a partir de CTE e células do cordão umbilical. Os animais que receberam as células do SCU apresentaram uma taxa mais elevada de enxertia em comparação aos que receberam ás células diferenciadas a partir de CTE humanas. Foi confirmado que após quinze dias do transplante, a hematopoese é restabelecida e que células CD45+ humanas estavam presentes, porém em baixas quantidades. Sobretudo, os resultados aqui apresentados enfatizaram o descrito na literatura, porém não ultrapassando a 1,5% de enxertia na medula óssea. Estes dados indicaram que os camundongos NSG proporcionaram um microambiente hematopoético favorável para as CTE humanas porém, essas células precisam ser investigadas no que tange aos fatores que aumentem de sua duração in vivo, otimizando a enxertia. / Hematopoietic stem cell transplantation (HSC) is the most widely used type of cell therapy nowadays. Human bone marrow, mobilized peripheral blood, and stem cells in the umbilical cord (UC) are the only sources of cells used clinically for hematopoietic recovery, but they have limited availability and only a third of patients have a matching donor. An alternative source to supply this demand would be hematopoietic cells derived from pluripotent stem cells. Embryonic stem cells (ESC) are a type of pulp-like cells characterized by their unlimited capacity for self-renewal and differentiation in all specialized cells of the adult individual. The high differentiation capacity of these cells in specific strains by in vitro induction methods makes great promises for the development of new technologies applicable to regenerative medicine and cell therapy. However, it remains to be determined whether hematopoietic stem cells (HTC) generated from pluripotent cells are functional in vivo. Thus, the objective of this study was to develop an animal model for the transplantation of human hematopoietic cells from pluripotent cells and to use HTC in the umbilical cord blood as a control. To do so, we performed standardization of the sublethal irradiation dose on the NOD / SCID IL2R ? null (NSG) mice and used two concentrations of cells, 1x106 and 0.75x106 hematopoietic cells differentiated from ESC and umbilical cord cells. The animals that received UC cells had a higher rate of grafting compared to those that received the differentiated cells from the human ESC. It was confirmed that after fifteen days of transplantation, hematopoiesis restored and that human CD45+ cells were present, but in low amounts. Above all, the results presented here emphasize the described in the literature, but not exceeding 1.5% of grafting in bone marrow. These data indicated that the NSG mice provided a hematopoietic microenvironment favorable to the human ESC, however, these cells need to be investigated with regard to factors that increase their duration in vivo, optimizing grafting.
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Neutropenia febril em coorte de adultos submetidos ao transplante de células-tronco hematopoiéticas / Febrile neutropenia in a cohort of adults submitted to hematopoietic stem cell transplantation.Kuwano, Mayumi Araujo 07 August 2018 (has links)
Introdução: A neutropenia febril (NF) é um evento adverso intrínseco ao transplante de células-tronco hematopoiéticas (TCTH), decorrente da mielossupressão ocasionada pelo procedimento, que impacta de modo importante na morbidade e na mortalidade do paciente. Objetivos: Analisar os pacientes submetidos ao TCTH quanto a ocorrência de NF. Método: Coorte retrospectiva conduzida com 61 pacientes submetidos ao TCTH no Hospital de Clínicas da Universidade Estadual de Campinas. Foram extraídos dados relativos a características basais dos pacientes, procedimento de TCTH, tempo de internação e desfecho clínico para determinar os fatores associados à NF. As variáveis independentes foram idade, sexo, comorbidades, diagnóstico, tipo de transplante, regime de condicionamento, fonte das células, nº de CD34, tempo de enxertia, escore de risco pré-TCTH do EBMT, SAPSII. A NF foi definida de acordo com o Common Terminology Criteria for Adverse Events (CTC/AE) v4.0, considerando o desfecho dicotômico, a duração em dias, a data da ocorrência, o grau e a análise de sobrevida. Os dados foram analisados por meio de testes paramétricos e não paramétricos, dependendo do nível de mensuração das variáveis e utilizaram-se Kaplan-Meier e regressão logística. Para todas as análises considerou-se nível de significância de 5%. Resultados: A incidência de NF nos pacientes submetidos ao TCTH foi de 78,7%, com duração média de 8,3 dias, sem diferença significativa entre os tipos de transplantes (p=0,176). Não foram encontrados fatores de risco para a NF, porém, os pacientes submetidos ao transplante autólogo (p=0,022) e ao regime de condicionamento mieloablativo (p=0,026) apresentaram menor sobrevida para este evento adverso. Os pacientes que utilizaram ventilação mecânica (p=0,052), que necessitaram do uso de drogas vasoativas (p=0,012) e que foram a óbito (OR=9,66; p=0,052), apresentaram NF em sua totalidade. Conclusão: A incidência de NF foi expressiva e, ainda que não tenham sido identificados fatores associados a ela, os pacientes submetidos ao regime NMA e TCTH alogênico apresentaram maior sobrevida para o surgimento de NF. Estes achados relativos a sobrevida podem subsidiar o enfermeiro na proposição de intervenções, visando evitar complicações infecciosas decorrentes da NF. / Introduction: Febrile neutropenia (FN) is an intrinsic adverse event to hematopoietic stem cell transplantation (HSCT), due to the myelosuppression caused by the procedure, which has an important impact on patient morbidity and mortality. Objectives: To analyze the patients submitted to HSCT regarding the occurrence of FN. Method: Retrospective cohort with 61 patients submitted to HSCT at Hospital de Clínicas, State University of Campinas. Data were extracted on the baseline information of patients, HSCT procedure, time of hospitalization and clinical outcome to determine the factors associated with FN. The independent variables were age, gender, comorbidities, diagnosis, type of transplantation, conditioning regime, cell source, CD34 number, grafting time, pre-HSCT risk score of EBMT, SAPSII. The FN was defined according to the Common Terminology Criteria for Adverse Events (CTC / AE) v4.0, considering the dichotomous outcome, duration in days, date of occurrence, degree and survival analysis. Data were analyzed using parametric and non-parametric tests, depending on the level of measurement of the variables and Kaplan-Meier and logistic regression were used. A significance level of 5% was considered for all analyzes. Results: The incidence of FN in patients submitted to HSCT was 78.7%, with an average duration of 8.3 days, with no significant difference between the types of transplants (p = 0.176). No risk factors were found for FN, however, patients submitted to autologous transplantation (p = 0.022) and myeloablative conditioning (p = 0.026) presented lower survival rates for this adverse event. Patients who used mechanical ventilation (p = 0.052), who required the use of vasoactive drugs (p = 0.012) and who died (OR = 9.66, p = 0.052) presented FN in their entirety. In addition, the occurrence of FN had an association with longer hospitalization time (p = 0.003). Conclusion: The incidence of FN was significant. Although no associated factors were identified, patients submitted to NMA and allogeneic HSCT presented a higher survival rate for the onset of FN. These findings regarding survival can subsidize the nurse in proposing interventions, in order to avoid infectious complications due to FN.
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Células-tronco pluripotentes induzidas para o estudo e tratamento da anemia falciforme / Induced pluripotent stem cell for study and treatment of sickle cell anemiaReis, Luiza Cunha Junqueira 25 April 2017 (has links)
A anemia falciforme (AF) é uma doença monogênica de elevada mortalidade e morbidade, que afeta milhões de pessoas em todo o mundo. Não há tratamento definitivo que seja amplo, eficaz e seguro para a AF, de forma que os tratamentos paliativos são os mais utilizados. O tratamento definitivo disponível é transplante alogênico de células-tronco hematopoiéticas, porém com várias complicações envolvidas. O estabelecimento de um modelo in vitro permite uma melhor compreensão de como a doença ocorre, além de permitir o desenvolvimento de novos testes e tratamentos mais eficazes contra a doença. Neste contexto, a tecnologia das células-tronco pluripotentes induzidas (iPSC), que surgiu em 2006, é uma ferramenta poderosa na pesquisa básica, na pesquisa da diferenciação de tecidos e no modelamento de doenças, e uma promessa para futuras aplicações clínicas, na descoberta e triagem de novas drogas mais eficazes e seguras, além da possibilidade de utilização na medicina regenerativa, na produção de células paciente-específicas para terapia celular. Este trabalho teve como objetivo obter um modelo de estudo e tratamento da AF utilizando iPSC. Para isso, vetores epissomais foram utilizados para a reprogramação de células mononucleares de sangue periférico para obter iPSC livres de integração. Estas células foram coletadas de pacientes tratados com o medicamento hidroxiureia e sem tratamento, para avaliação do impacto da droga na reprogramação. As linhagens de iPSC PBscd geradas foram caracterizadas quanto ao potencial pluripotente e de diferenciação. Todas as linhagens geradas se mostraram pluripotentes com potencial de auto renovação e potencial de formar células e tecidos dos 3 folhetos germinativos. O rastreamento dos vetores utilizados na reprogramação mostrou que as células estão livres após cerca de 10 passagens em média, e que eles não se integram espontaneamente nas células. As linhagens de iPSC foram diferenciadas em progenitores hematopoiéticos através da agregação forçada associada à indução com citocinas específicas e um cultivo em suspensão. Dessa forma, nós obtivemos um protocolo dinâmico e eficiente de produção de células CD34+CD45+ com poucos dias de indução. Foram realizados experimentos iniciais de padronização da metodologia de CRISPR, para que essa metodologia possa ser utilizada no futuro para a correção da mutação da AF no gene da ?- globin. Além disso, a reação padronizada para o rastreamento da mutação no gene da ?-globin poderá ser usado em experimentos futuros de edição gênica para avaliar a correção da mutação. Em resumo, oferecemos uma ferramenta valiosa para uma melhor compreensão de como a AF ocorre, além de tornar possível o desenvolvimento de drogas e tratamentos mais eficazes e de fornecer um melhor entendimento dos tratamentos amplamente utilizados, como a hidroxiurea / Sickle cell anemia (SCA) is a monogenic disease of high mortality and morbidity, that affects millions of people worldwide. There is no definitive treatment that is broad, effective and safe for SCA, so the palliative treatments are the most used. The definitive treatment available is the allogeneic transplantation of hematopoietic stem cells, but with several complications involved. The establishment of an in vitro model allows better understanding of how the disease occurs, besides allowing the development of more effective new tests and treatments against the disease. In this context, the induced pluripotent stem cell (iPSC) technology, that emerged in 2006, is a powerful tool for basic research, tissue differentiation research and disease modeling, and a promise for future clinical applications, to find and screen new, more effective and safe drugs, besides the possibility of use in regenerative medicine, in the production of patient-specific cells for cell therapy. This work aimed to obtain a model for study and treatment of SCA using iPSC. For this, episomal vectors were used for reprogramming peripheral blood mononuclear cells to obtain integration-free iPSC. This cells were collected from patients treated with hydroxyurea and without treatment, for evaluation of the impact of the drug in reprogramming. The generated iPSC PBscd lines were characterized for pluripotent and differentiation potential. All the generated lines were shown to be pluripotent with potential for self-renewal and to form cells and tissues of the 3 germ layers. Screening of the vectors used for reprogramming showed that they are absent after about 10 passages, and that they do not integrate spontaneously into the cells. The iPSC lines were differentiated into hematopoietic progenitors through forced aggregation associated with induction with specific cytokines and culture in cell suspension. Thus, we obtained a dynamic and efficient protocol of CD34+CD45+ cells production with a few days of induction. Initial standardization experiments of CRISPR methodology was performed, so that this methodology can be used in the future to correct the ?-globin chain mutation of SCA. Also, the standardized reaction for the screening of ?-globin chain mutation can be used in future gene-editing experiments to evaluate the mutation correction. In summary, we offer a valuable tool for a better understanding of how SCA occurs, in addition to make possible the development of more effective drugs and treatments and providing better understanding of widely used treatments, such hydroxyrea
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Obtenção e caracterização de células embrionárias indiferenciadas de Syssphinx molina (Cramer) (Lepidoptera, Saturniidae) / Collection and characterization of undifferentiated embryonic cells of Syssphinx molina (Cramer, 1871) (Lepidoptera, Saturniidae)Câmara, Joseleide Teixeira 26 April 2017 (has links)
Syssphinx molina (Cramer) é considerada uma espécie de interesse fitossanitário, pois pode ser praga de algumas plantas cultivadas pelo homem, além disso, em lavouras de monoculturas podem ocorrer acidentes com as larvas dessa espécie, causando dermatites nos trabalhadores. O principal objetivo desse estudo é obter e caracterizar as células embrionárias indiferenciadas de Syssphinx molina. Ovos da espécie serão obtidos através de mariposas fêmeas grávidas, coletadas pela equipe da Coleção Zoológica do Maranhão (CZMA), da Universidade Estadual do Maranhão (UEMA), Campus Caxias. Os ovos foram caracterizados e comparados com ovos de outras espécies filogeneticamente próximas à S. molina. Culturas primárias de células embrionárias de S. molina foram cultivadas por 20 dias, ocorreram duas passagens e procedeu-se com o congelamento. Após descongelamento das células ocorreram 10 passagens. Foram analisadas amostras de células de cada passagem para obter dados do ciclo célular e características das células através de uso de marcadores: Anti-Axons, Anti-Caspase 3 ativa, Anti-CD105, Anti-CD117, Anti-CD24, Anti-CD43, Anti-CD73, Anti-CD90/Thy1, Anti-Ciclina D1, Anti GM 130, Anti-HLA DR, Anti-HSP47, Anti-HSP70,. Anti-KI67, Anti-MCP1, Anti- Oct 3/4, Anti-p53, Anti RAB 5, Anti-SSEA4, Anti-Stro-1, Anti-TGF beta 1, Anti-Vimentina e Schneider L2. Pela primeira vez é determinado um protocolo para resfriamento de ovos de S. molina, assim como protocolo para cultura primária e secundária de células embrionárias dessa espécie. São analisadas também as idades gestacionais dos ovos de S. molina e comparadas com ovos de outras espécies de mariposas da mesma subfamília. A análise de ciclo celular e marcadores confirmam a alta taxa de proliferação das células, no entanto, a análise com os anticorpos Anti-Caspase 3 ativa e Anti-P53 mostrou o percentual de morte celular programada (apoptose) é, geralmente, maior que 25% nas populações de células analisadas. Os marcadores Anti GM130 e Anti RAB 5, que participam, respectivamente, do recrutamento de proteínas pela fase cis do aparelho de Golgi e do processo de maturação do endossoma, marcaram mais de 50% das células das amostras analisadas. Anti-HLA-DR, que revela proteínas da membrana do linfócito T, com um percentual geralmente superior a 30% de marcação. Dentre os marcadores de células multi e pluripotentes, aquele que marcou maior taxa de células foi Anti- CD117, que se liga em células estaminais hematopoiéticas. Todos os anticorpos utilizados para marcar células do sistema hematopoiético (Anti-CD24, Anti-CD43, Anti-CD73, Anti-CD90/Thy1, Anti-HLA DR e Anti-MCP1) foram expressos nas células cultivadas de S. molina. Portanto, entende-se que os insetos, a exemplo de S. molina, são um grupo que possuem atividades metabólicas complexas e o entendimento dessas atividades permitirá, no futuro, delinear novas formas de controle biológico. Além disso, os dados inéditos sobre o sistema hematopoiético dos insetos apresentado nesse trabalho, além constitui um subsídio fundamental para estabelecer futuros modelos importantes para estudos de estratégias de controle biológico, como também poderá auxiliar no desenvolvimento de técnicas para combater doenças transmitidas por insetos. / Syssphinx molina (Cramer) is considered a species of phytosanitary interest, it can be curse of some plants cultivated by man, in addition, in monoculture plantations, accidents may occur with the larvae of this species, causing dermatitis in workers. The main objective of this study is to obtain and characterize the undifferentiated embryonic cells of Syssphinx molina. Eggs of the species will be obtained through pregnant female moths, collected by the team of the Coleção Zoológica do Maranhão (CZMA), Universidade Estadual do Maranhão (UEMA), Campus Caxias-MA. The eggs were characterized and compared with eggs of other phylogenetically close species of S. molina. Primary cultures of S. molina embryonic cells were cultured for 20 days, Two passes occurred and proceeded with freezing. After thawing of the cells, there were 10 passes. Cell samples from each passage were analyzed to obtain cell cycle data and cell characteristics through the use of markers: Anti-Axons, Anti-Caspase 3 ativa, Anti-CD105, Anti-CD117, Anti-CD24, Anti-CD43, Anti-CD73, Anti-CD90/Thy1, Anti-Ciclina D1, Anti GM 130, Anti-HLA DR, Anti-HSP47, Anti-HSP70,. Anti-KI67, Anti-MCP1, Anti- Oct 3/4, Anti-p53, Anti RAB 5, Anti-SSEA4, Anti-Stro-1, Anti-TGF beta 1, Anti-Vimentina e Schneider L2. For the first time a protocol for cooling eggs of S. molina is determined, as well as protocol for primary and secondary culture of embryonic cells of this species. The gestational age of S. molina eggs and compared to eggs of other species of moths of the same subfamily. Cell cycle analysis and markers confirm the high rate of cell proliferation, however, analysis with the active Anti-Caspase 3 and Anti-P53 antibodies showed the percentage of programmed cell death (apoptosis) is generally greater than 25 % in the analyzed cell populations. Markers Anti GM130 and anti RAB 5, which participate respectively, recruitment of proteins by cis phase of the Golgi apparatus and endosome maturation process, scored more than 50% of the cells in the samples analyzed. Anti-HLA-DR, which reveals T lymphocyte membrane proteins, with a percentage generally greater than 30% labeling. Among the multi- and pluripotent cell markers, the one that scored the highest cell rate was Anti-CD117, which binds to hematopoietic stem cells. All antibodies used to label cells from the hematopoietic system (Anti-CD24, Anti-CD43, Anti-CD73, Anti-CD90 / Thy1, Anti-HLA DR and Anti-MCP1) were expressed in the cultured cells of S. molina. Therefore, it is understood that insects, like S. molina, are a group that has complex metabolic activities and the understanding of these activities will, in the future, outline new forms of biological control. In addition, the unpublished data on the hamatopoietic system of insects presented in this work, beyond is a key benefit to establish future important models for studies of biological control strategies, but may also assist in the development of techniques to combat diseases transmitted by insects.
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