977 resultados para Bone Marrow Cells


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Keratinocyte Growth factor (KGF) is an epithelial cell growth factor of the fibroblast growth factor family and is produced by fibroblasts and microvascular endothelium in response to proinflammatory cytokines and steroid hormones. KGF is a heparin binding growth factor that exerts effects on epithelial cells in a paracrine fashion through interaction with KGF receptors. Preclinical data has demonstrated that KGF can prevent lung and gastrointestinal toxicity following chemotherapy and radiation and preliminary clinical data in the later setting supports these findings. In the experimental allogeneic bone marrow transplant scenario KGF has shown significant ability to prevent graft-versus-host disease by maintaining gastrointestinal tract integrity and acting as a cytokine shield to prevent subsequent proinflammatory cytokine generation. Within this setting KGF has also shown an ability to prevent experimental idiopathic pneumonia syndrome by stimulating production of surfactant protein A, promoting alveolar epithelialization and attenuating immune-mediated injury. Perhaps most unexpectantly, KGF appears able to maintain thymic function during allogeneic stern cell transplantation and so promote T cell engraftment and reconstitution. These data suggest that KGF will find a therapeutic role in the prevention of epithelial toxicity following intensive chemotherapy and radiotherapy protocols and in allogeneic stem cell transplantation.

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The mononuclear phagocyte system (MPS) was defined as a family of cells comprising bone marrow progenitors, blood monocytes, and tissue macrophages. In this review, we briefly consider markers for cells of this lineage in the mouse, especially the F4/80 surface antigen and the receptor for macrophage colony-stimulating factor. The concept of the MPS is challenged by evidence that there is a separate embryonic phagocyte lineage, the blurring of the boundaries between macrophages and other cells types arising from phenotypic plasticity and transdifferentiation, and evidence of local renewal of tissue macrophage populations as opposed to monocyte recruitment. Nevertheless, there is a unity to cells of the MPS suggested by their location, morphology, and shared markers. We discuss the origins of macrophage heterogeneity and argue that macrophages and antigen-representing dendritic cells are closely related and part of the MPS.

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Purpose: The purpose of this investigation was to evaluate the impact of undertaking peripheral blood stem cell transplantation (PBST) on T-cell number and function, and to determine the role of a mixed type, moderate intensity exercise program in facilitating the recovery of T-cell number and function. Methods: Immunological measures of white blood cell, lymphocyte, CD3(+), CD4(+), and CD8(+) counts, and CD3(+) cell function were assessed pretransplant (PI), immediately posttransplant (PII), and 1 month (II), 2 months (12) and 3 months (PIII) posttransplant. After PII, 12 patients were divided equally into a control group (CG) or exercise intervention group (EG). Results: Lower total T-cell, helper T-cell, and suppressor T-cell counts (P < 0.01), as well as lower T-cell function (P < 0.01), when compared with normative data, were found at PI. More specifically, 88% of the group had CD3(+), CD4(+), and CD8(+) counts that were more than 40%, 20%, and 50% below normal at PI, respectively. Undertaking a PBST caused further adverse changes to the total leukocyte, lymphocyte, CD3(+), CD4(+) and CD8(+) count. and the helper/suppressor ratio. Although CD8(+) counts had returned to normal by PIII, CD3(+), CD4(+), and the CD4(+)/CD8(+) ratio remained significantly lower than normative data (P < 0.01), with 66%, 100%, and 100% of the subject group reporting counts and ratios, respectively, below the normal range. Conclusion: The PBST patients were immunocompromised before undertaking the transplant, and the transplant procedure imposed further adverse changes to the leukocyte and lymphocyte counts. The leukocyte and CD8(+) counts returned to normal within 3 months posttransplant; however, the other immunological parameters assessed demonstrated a delayed recovery. Although participation in the exercise program did not facilitate a faster immune cell recovery, neither did the exercise program hinder or delay recovery.

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The outcome of dendritic cell (DC) presentation of Ag to T cells via the TCR/MHC synapse is determined by second signaling through CD80/86 and, importantly, by ligation of costimulatory ligands and receptors located at the DC and T cell surfaces. Downstream signaling triggered by costimulatory molecule ligation results in reciprocal DC and T cell activation and survival, which predisposes to enhanced T cell-mediated immune responses. In this study, we used adenoviral vectors to express a model tumor Ag (the E7 oncoprotein of human papillomavirus 16) with or without coexpression of receptor activator of NF-kappaB (RANK)/RANK ligand (RANKL) or CD40/CD40L costimulatory molecules, and used these transgenic DCs to immunize mice for the generation of E7-directed CD8(+) T cell responses. We show that coexpression of RANK/RANKL, but not CD40/CD40L, in E7-expressing DCs augmented E7-specific IFN-gamma-secreting effector and memory T cells and E7-specific CTLs. These responses were also augmented by coexpression of T cell costimulatory molecules (RANKL and CD40L) or DC costimulatory molecules (RANK and CD40) in the E7-expressing DC immunogens. Augmentation of CTL responses correlated with up-regulation of CD80 and CD86 expression in DCs transduced with costimulatory molecules, suggesting a mechanism for enhanced T cell activation/survival. These results have generic implications for improved tumor Ag-expressing DC vaccines, and specific implications for a DC-based vaccine approach for human papillomavirus 16-associated cervical carcinoma.

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A Anemia de Fanconi (AF) é uma doença recessiva rara, com uma frequência estimada de 4 a 7 por 1 000 000 de nascimentos. Caraterizase por malformações congénitas, falência medular e hipersensibilidade a agentes clastogénicos de DNA. Devido à grande complexidade desta patologia a primeira abordagem de diagnóstico, consiste na análise da instabilidade cromossómica, após cultura celular com estimulação com agentes clastogénicos diepoxibutano (DEB) ou mitomicina C (MMC). Realizou- se um estudo retrospetivo de 34 anos (1980-2014) em 243 amostras com suspeita de AF e de 25 amostras de familiares de doentes de AF, num total de 268 amostras. Nas 243 amostras suspeitas de Anemia de Fanconi, foram identificadas 37 com AF. A idade média ao diagnóstico foi de 7 anos, existindo um ligeiro predomínio da incidência no sexo feminino (59%). Uma amostra foi classificada como AF(-/+). Nos familiares de doentes com AF foram identificados 2 casos positivos, o que perfaz 39 amostras de AF positivas. Em quatro das amostras AF negativas, observaram-se cariotipos anormais. Estes resultados não permitem estimar uma frequência de doentes de AF em Portugal, uma vez que não englobam indivíduos de todas as regiões portuguesas, mas permitem uma estimativa da frequência espectável.

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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

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Eosinophil dynamics, in bone marrow, blood and peritoneal exudate, of resistant C57B1/6 (C57) and susceptible A/Snell (A/Sn) mice was comparatively studied during the acute phase of infection by Trypanosoma cruzi Y strain. A decline was observed in bone marrow eosinophil levels in A/Sn, but not in C57 mice, soon after infection, those of the former remaining significantly below those of the latter up to the 4th day of infection. Bone marrow eosinophil levels of C57 mice declined subsequently to levels comparable to those of A/Sn mice, the number of these cells in this compartment remaining 50% those of non infected controls, in both strains, up to the end of the experiment on the 14th day of infection. The fluctuations in eosinophil levels in blood and peritoneal space were similar in both mice strains studied. Concomitantly with depletion of eosinophils in the marrow, depletion in blood and a marked rise of these cells in the peritoneal space, initial site of infection, occurred in both strains. The difference in eosinophil bone marrow levels, between C57 and A/Sn mice, observed in the first four days of infection, suggests a higher eosinopoiesis capacity of the former in this period, which might contribute to their higher resistance to T. cruzi infection.

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The present study has intended to contribute to the elucidation of the pathogenic mechanisms, involved in the thrombocytopenia and in the bleeding diathesis seen in the course of Leptospirosis. The group of cases included in the present prospective study consisted of 30 patients with Leptospirosis, admitted to the Infectious and Parasitic Diseases Ward, Hospital das Clínicas, Faculty of Medicine, University of São Paulo. The following possible mechanisms of thrombocytopenia have been considered and therefore investigated: platelet consumption, due to disseminated intravascular coagulation; immune-mediated platelet destruction, due to platelet-associated antibodies and an inhibited platelet production in the bone marrow. Thrombocytopenia occurred in 86.6% of 30 patients and did not seem to be immune-mediated by platelet-associated antibodies. Furthermore it did not seem to be due to a disseminated intravascular coagulation consumption. Although there was a statistically-significant correlation between bone marrow platelet production and platelet counts we think that the static microscopic examination of a bone marrow aspirate cannot accurately depict the dynamic mechanisms of platelet production when these cells are being consumed in peripheral blood. Vasculitis should be considered as the most important factor for the pathogenesis of the bleeding disturbances in Leptospirosis. However, we believe that thrombocytopenia, uremia and coagulation disorders, individually or as a group, should be included among the contributing factors that lead to and worsen bleeding episodes, which represent the leading cause of death in this disease.

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EPO is a glycoprotein produced in the kidney, which stimulates the division and differentiation of red cells in the bone marrow. Erythropoietin is available as a therapeutic agent produced by recombinant DNA technology in mammalian cell culture into which the human EPO gene has been transfected. Biosimilar Epoetins are mostly erythropoietins of the Epoetin alfa, beta or omega type, which are being produced at much lower cost due to expired patents. Recombinant human erythropoietin (rh-EPO) contains the identical amino acid sequence of natural EPO: 165 amino acids, with a molecular weight of 30,400 Da. Since glycosylation is not only dependent on the cell-line used for the expression of Epoetins but also on the entire biotechnological process the glycosylation patterns of biosimilars do not necessarily reflect the patterns of the originator compounds. Today biosimilar Epoetins are manufactured and distributed worldwide and under many different names. The use of recombinant EPOs for doping is prohibited because of its performance enhancing effect. The aim of the present study was to investigated whether biosimilar alpha r-HuEPO – ior®-EPOCIM, produced in Cuba and also available in other countries in all continents, could be differentiated from endogenous one by iso-electro-focusing plus double blotting, SDS-PAGE and SAR-PAGE for antidoping analysis.

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INTRODUCTION: Clopidogrel is frequently associated with thrombotic thrombocytopenic purpura, however this drug is rarely related to severe isolated thrombocytopenia. Pentoxifylline has previously been associated with thrombocytopenia only once. To the best of our knowledge, this is the first report of severe isolated thrombocytopenia after therapy with both clopidogrel and pentoxyfilline. CASE PRESENTATION: We report the case of a 79-year-old Caucasian man who presented to our facility with intermittent claudication. He had obliterative arterial disease and started therapy with clopidogrel and pentoxifylline. His basal platelet count was 194 × 109 cells/L. At three days after the start of treatment, our patient had lower limb petechia and stopped taking clopidogrel and pentoxifylline. His platelet count lowered to 4 × 109 cells/L and our patient was admitted to hospital. Our patient had purpura with no other hemorrhages or splenomegaly. Results of a blood smear were normal, and a bone marrow study showed dysmegakaryopoiesis. Antiplatelet antibody test results were negative, as were all viral serology tests. Imaging study results were normal. Our patient was given immunoglobulin but there was no sustained platelet increase, so corticotherapy was started as the next treatment step. At five months after clopidogrel and pentoxifylline were discontinued, his platelet count continued increasing even after prednisolone was tapered. CONCLUSIONS: Severe isolated thrombocytopenia may appear as a side effect when using clopidogrel and pentoxifylline. These drugs are widely used by general physicians, internists, cardiologists and vascular surgeons. We hope this report will raise awareness of the need to monitor the platelet count in patients taking these drugs.

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Existem raríssimos casos citados de granulomas da medula óssea por iatrogenia ao alopurinol. Os granulomas são um achado raro nas biópsias da medula óssea e podem ter várias etiologias, nomeadamente infeciosas, neoplásicas, autoimunes, iatrogénicas ou sarcoidose. Na ausência de características patognomónicas, recorre-se à integração de dados clínicos, laboratoriais, imagiológicos e histológicos para estabelecer o diagnóstico. Descrevemos o caso de um caucasiano, 59 anos, referenciado à consulta de Medicina por gota úrica, tendo sido medicado com alopurinol e colchicina. Ao longo do seguimento surgiram anemia e trombocitopenia. Do estudo por mielograma e biópsia osteomedular salientavam-se “numerosos granulomas de tipo epitelióide, sem células multinucleadas, sem identifica- ção de microrganismos PAS pós diástase ou Ziehl-Neelsen, sem neoplasia, compatível com mielite granulomatosa”. A etiologia estabelecida foi a de reação de hipersensibilidade ao alopurinol pelo que foi descontinuado. Repetido o exame um ano depois, não se observaram granulomas, facto que reforçou a hipótese diagnóstica.

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Blastic plasmacytoid dendritic cell neoplasm is a rare and aggressive hematodermic neoplasia with frequent cutaneous involvement and leukemic dissemination. We report the case of a 76-year-old man with a 2 month history of violaceous nodules and a tumor with stony consistency, located on the head, and mandibular, cervical and supraclavicular lymphadenopathies. Multiple thoracic and abdominal adenopathies were identified on computerized tomography. Flow cytometry analysis of the skin, lymph node and bone marrow biopsies demonstrated the presence of plasmocytoid dendritic cell neoplastic precursor cells (CD4+, CD45+, CD56+ and CD123+ phenotype). After initial clinical and laboratorial complete remission with chemotherapy, the patient died due to relapse of the disease associated with the appearance of a cervical mass with medullary compromise.

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The term “mastocytosis” denotes a heterogeneous group of disorders characterised by abnormal growth and accumulation of mast cells (MC) in one or more organ systems. Symptoms result from MC chemical mediator’s release, pathologic infiltration of neoplastic MC in tissues or both. Multiple molecular, genetic and chromosomal defects seem to contribute to an autonomous growth, but somatic c-kit D816V mutation is more frequently encountered, especially in systemic disease. We present a literature review of mastocytosis and a rare case report of an 18 month-old-girl with a bullous dermatosis, respiratory distress and anaphylaxis, as clinical manifestations of mastocytosis. The developments of accepted classification systems and novel useful markers allowed a re-evaluation and updating of the classification of mastocytosis. In paediatric age cutaneous forms of disease prevail and may regress spontaneously. SM is more frequently diagnosed in adults and is a persistent(clonal) disease of bone marrow. The clinical course in these patients is variable.Today diagnostic criteria for each disease variant are reasonably well defined. There are, however, peculiarities, namely in paediatric age, that makes the diagnostic approach difficult. Systemic disease may pose differential diagnostic problems resulting from multiple organ systems involvement. Coversly, the “unexplained” appearance of those symptoms with no skin lesions should raise the suspicion of MC disease. This case is reported in order to stress the clinical severity and difficult diagnostic approach that paediatric mastocytosis may assume.

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Oral busulfan is the historical backbone of the busulfan+cyclophosphamide regimen for autologous stem cell transplantation. However intravenous busulfan has more predictable pharmacokinetics and less toxicity than oral busulfan; we, therefore, retrospectively analyzed data from 952 patients with acute myeloid leukemia who received intravenous busulfan for autologous stem cell transplantation. Most patients were male (n=531, 56%), and the median age at transplantation was 50.5 years. Two-year overall survival, leukemia-free survival, and relapse incidence were 67±2%, 53±2%, and 40±2%, respectively. The non-relapse mortality rate at 2 years was 7±1%. Five patients died from veno-occlusive disease. Overall leukemia-free survival and relapse incidence at 2 years did not differ significantly between the 815 patients transplanted in first complete remission (52±2% and 40±2%, respectively) and the 137 patients transplanted in second complete remission (58±5% and 35±5%, respectively). Cytogenetic risk classification and age were significant prognostic factors: the 2-year leukemia-free survival was 63±4% in patients with good risk cytogenetics, 52±3% in those with intermediate risk cytogenetics, and 37 ± 10% in those with poor risk cytogenetics (P=0.01); patients ≤50 years old had better overall survival (77±2% versus 56±3%; P<0.001), leukemia-free survival (61±3% versus 45±3%; P<0.001), relapse incidence (35±2% versus 45±3%; P<0.005), and non-relapse mortality (4±1% versus 10±2%; P<0.001) than older patients. The combination of intravenous busulfan and high-dose melphalan was associated with the best overall survival (75±4%). Our results suggest that the use of intravenous busulfan simplifies the autograft procedure and confirm the usefulness of autologous stem cell transplantation in acute myeloid leukemia. As in allogeneic transplantation, veno-occlusive disease is an uncommon complication after an autograft using intravenous busulfan.

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INTRODUCTION: Canine visceral leishmaniasis (CVL) is a zoonotic disease with different clinical manifestations. Parasitism often occurs in bone marrow, but changes have been observed in peripheral blood and serum biochemical parameters. The aim of this study was to evaluate the hematological and biochemical parameters in dogs naturally infected by Leishmania chagasi. METHODS: Eighty-five adult dogs of both sexes and various weights and ages from the Zoonosis Control Center of Fortaleza (CCZ) were used, selected by immunofluorescence assay (IFA) and considered positive with IFA titers greater than 1:40 and by visualizing amastigotes of Leishmania chagasi in smears obtained by bone marrow aspiration. The dogs (n = 85) were grouped according to clinical signs: negative (CN = 7), subclinical (CS = 10), and clinical (CC = 68). Blood samples were collected for determination of hematological and biochemical serum values. The experimental protocol was approved by the CEUA/UECE. RESULTS: The most frequent clinical signs were cachexia (77.9%), keratitis (61.8%), and lymphadenopathy (55.9%), and 86.8% of the animals showed more than one clinical sign characteristic of CVL. In CC were observed reductions in red blood cells (63%), hematocrit (72%), and hemoglobin (62%), as well as leukocytosis (33%), neutropenia (28%), thrombocytopenia (50%), uremia (45%), hyperproteinemia (53%, p<0.05), hypergammaglobulinemia (62%, p<0.01), and hypoalbuminemia (58%). CONCLUSIONS: Animals with the clinical form of the disease demonstrate hematological and biochemical changes consistent with anemia, uremia, hyperproteinemia, and hyperglobulinemia, which present themselves as strong clinical markers of visceral leishmaniasis associated with the signs previously reported.