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- ItemSomente MetadadadosActivation of P2Y(1) receptor triggers two calcium signaling pathways in bone marrow erythroblasts(Elsevier B.V., 2006-03-18) Paredes-Gamero, E. J.; Craveiro, R. B.; Pesquero, J. B.; Franca, J. P.; Oshiro, MEM; Ferreira, A. T.; Universidade Federal de São Paulo (UNIFESP)In this study, we describe the presence of P2 receptor subtypes and Ca2+ signaling in erythroblasts. ATP and ADP produced a biphasic increase of intracellular Ca2+ concentration ([Ca2+],), with an initial transient phase followed by a sustained phase. Reverse transcription polymerase chain reaction (RT-PCR) showed the expression of P2Y(1), P2Y(2) and P2Y(12). the selective P2Y(1) receptor antagonist 2'-deoxy-N-6-methyl-adenosine- 3',5'diphosphate (MRS2179) and the Gi protein inhibitor pertussis toxin blocked Ca2+ increase. the initial transient [Ca2+](i) increase phase was sensitive to the 1,4,5-inositol trisphosphate (IP3) receptor blocker 2-aminoethoxy-diphenylborate (2-APB), while the sustained phase was sensitive to the protein kinase C (PKC) inhibitor 2-[1-(3-dimethylaminopropyl)-1H-indol-3-yl]-3(1H-indol-3-yl)-maleimide (GF109203X) and calcium calmodulin kinase 11 (CaMKII) inhibitor 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine (KN-62). in addition, the PKC activator phorbol-12,13-dibutyrate (PDBu) produced increase of [Ca2+](i). Flow cytometry analysis showed the expression of Ca2+-dependent PKC alpha, beta I, gamma and phospho-CaMKII.These results suggest that the activation of the P2Y(1) receptor triggers two different [Ca2+]i increase pathways, one IP3-dependent and the other kinase-dependent. (c) 2006 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosAmifostine does not prevent activation of TGF beta 1 but induces smad 7 activation in megakaryocytes irradiated in vivo(Wiley-Blackwell, 2002-11-01) Segreto, Helena Regina Comodo [UNIFESP]; Ferreira, Alice Teixeira [UNIFESP]; Kimura, Edna Teruko [UNIFESP]; Franco, Marcello [UNIFESP]; Egami, Mizue Imoto [UNIFESP]; Silva, Maria Regina Regis da [UNIFESP]; Segreto, Roberto Araujo [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)Experiments were undertaken to assess the role of amifostine in the activation of latent TGFbeta1 and in the smad proteins cascade (smad 2/3, smad4, smad7), focusing on megakaryocytes, in the bone marrow irradiated in vivo. Non-irradiated megakaryocytes were negative for active TGFbeta1. Immunopositivity to active TGFbeta1 was detected in megakaryocytes 10 days after irradiation in amifostine- treated and untreated marrows. Smad 2/3 and smad 4 were strongly positive in the nucleus of megakaryocytes 10 days after irradiation. At the same time, a predominant hypocellular bone marrow with foci of hematopoiesis was observed with few megakaryocytes. An increase in the number of reticulin fibers was also seen. in amifostine-treated marrows, smad 2/3 and smad4 were not detected in the nucleus but were positive in the cytoplasm of megakaryocytes 10 days after irradiation. Coincidentally, bone marrows were cellular with megakaryocytes. Smad7 immunoexpression was detected in the cytoplasm of megakaryocytes in the non-irradiated, amifostine-treated and in the irradiated, amifostine-treated marrows. Data indicate that amifostine does not prevent latent TGFbeta1 activation in irradiated megakaryocytes. While TGFbeta1 signal transduction occurs in megakaryocytes in untreated bone marrows, it is inhibited in megakaryocytes in amifostine-treated marrows due to the induction of smad 7 activation. This is the first report showing smad 7 activation by amifostine. Our results also suggest a role for TGFbeta1 as an inhibitor of megakaryocytes in vivo. (C) 2002 Wiley-Liss, Inc.
- ItemSomente MetadadadosThe bone marrow cells radioprotection by amifostine - NN/N ratio, apoptosis, ultrastructural and lipid matrix evaluation(Interciencia, 1999-04-01) Segreto, Roberto Araujo [UNIFESP]; Egami, Mizue Imoto [UNIFESP]; França, Jerônimo Pereira de [UNIFESP]; Silva, MRR; Ferreira, Alice Teixeira [UNIFESP]; Segreto, Helena Regina Comodo [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The present experiment was performed in order to estimate the amifostine-WR2721 (ami) bone marrow cells radioprotection, by the following parameters. NN/N ratio, the apoptotic cell counting, ultrastructural analysis and lipid matrix (membrane) injury evaluation.The protected marrows showed: significant low NN/N ratio (24h); significant low number of apoptotic cells (4,12h); better ultrastructural aspect (4,12,24h and 10 days); less lipid matrix injury (4h). These findings show that amifostine is an efficient radioprotector for the bone marrow cells.
- ItemSomente MetadadadosClinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft(Wiley-Blackwell, 2010-05-01) Pelegrine, Andre Antonio; Sorgi da Costa, Carlos Eduardo [UNIFESP]; Pizzigatti Correa, Maria Elvira; Comenalli Marques, Jose Francisco; Sao Leopoldo Mand Res Ctr; Universidade Federal de São Paulo (UNIFESP); Universidade Estadual de Campinas (UNICAMP)PurposeThe aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction.MaterialsThirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group. Hematologists collected 5 ml of bone marrow from the iliac crest of the patients in the test group immediately before the extractions. Following tooth extraction and elevation of a buccal full-thickness flap, titanium screws were positioned throughout the buccal to the lingual plate and were used as reference points for measurement purposes. the sockets were grafted with an autologous bone marrow in the test sites and nothing was grafted in the control sites. After 6 months, the sites were re-opened and bone loss measurements for thickness and height were taken. Additionally, before implant placement, bone cores were harvested and prepared for histologic and histomorphometric evaluation.ResultsThe test group showed better results (P < 0.05) in preserving alveolar ridges for thickness, with 1.14 +/- 0.87 mm (median 1) of bone loss, compared with the control group, which had 2.46 +/- 0.4 mm (median 2.5) of bone loss. the height of bone loss on the buccal plate was also greater in the control group than in the test group (P < 0.05), 1.17 +/- 0.26 mm (median 1) and 0.62+0.51 (median 0.5), respectively. in five locations in the control group, expansion or bone grafting complementary procedures were required to install implants while these procedures were not required for any of the locations in the test group. the histomorphometric analysis showed similar amounts of mineralized bone in both the control and the test groups, 42.87 +/- 11.33% (median 43.75%) and 45.47 +/- 7.21% (median 45%), respectively.ConclusionThese findings suggest that the autologous bone marrow graft can contribute to alveolar bone repair after tooth extraction.To cite this article:Pelegrine AA, da Costa CES, Correa MEP, Marques JFC Jr. Clinical and histomorphometric evaluation of extraction sockets treated with an autologous bone marrow graft.Clin. Oral Impl. Res. 21, 2010; 535-542.doi: 10.1111/j.1600-0501.2009.01891.x.
- ItemSomente MetadadadosEffects of palladacycle complex on hematopoietic progenitor cells proliferation in vivo and in vitro and its relation with the inhibitory properties of this compound on the angiotensin-I converting enzyme activity(Marcel Dekker Inc, 2004-01-01) Caires, ACF; Oliveira, C. R.; Smith, MCM; Hemerly, J. P.; Juliano, M. A.; Bincoletto, C.; Univ Mogi Das Cruzes; Universidade Estadual de Campinas (UNICAMP); Universidade Federal de São Paulo (UNIFESP)In the present study, we introduce a new class of organometallic compound, the Biphosphinic Palladacycle Complex [Pd (C-2, N-S(-)(dmpa)(dppf)] Cl (BPC), as an angiotensin-I converting-enzyme inhibitor (ACEI) with hematological regulation properties. When BPC was assayed as a competitive inhibitor over the hydrolysis of Abz-YRK (Dnp)-P-OH (Km = 7.0 muM), it showed a Kiapp = 0.2259 ng and a Ki value of 94.12 pg. Using murine long-term bone marrow cultures (LTBMCs) and clonal culture techniques, we also evaluated the capacity of this drug (1.18 muM) to module haematopoietic progenitor cells proliferation in vitro and in vivo. Our results demonstrated that BPC produces no toxicity to bone marrow cells, as determined by the unchanged cell number in the non-adherent layer at weeks 1, 2, and 8 and the increased number of adherent cells present in the BPC-treated LTBMCs. However, the proportion of CFU-Cs in the non-adherent cell layer was reduced at weeks 5, 6, 8, and 9. in vivo studies using the dose of 1 mg/kg of BPC, administered by subcutaneous route, presented similar result as those found in vitro, in the number of CFU-Cs. This latter finding may be explained by the inhibitory effects of this drug on the ACE activity, which probably result in increased levels of its substrate AcSDKP, a negative regulator of hematopoiesis.
- ItemAcesso aberto (Open Access)Histologia da medula óssea(Associação Brasileira de Hematologia e Hemoterapia e Terapia Celular, 2009-01-01) Alves, Antonio Correa [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)The bone marrow biopsy after the introduction of the Jamshidi needle has come into a routine practice due to the facilitation to obtain good sample. Due to the adequate size of the sample, the decalcification time decreased and consequently the histological quality improved allowing to the pathologist a more deep and precise morphological interpretation and diagnosis of the hematological and non- hematological disorders. For a correct diagnosis, the pathologist should be acquainted with the normal histology of the bone marrow parenchyma, it variations depending on age, as well as with the clinico- laboratorial data to integrate them with the morphological features.
- ItemSomente MetadadadosHuman Mesenchymal Stem Cells: From Immunophenotyping by Flow Cytometry to Clinical Applications(Wiley-Blackwell, 2013-01-01) Nery, Arthur A.; Nascimento, Isis Cristina [UNIFESP]; Glaser, Talita; Bassaneze, Vinicius; Krieger, Jose Eduardo; Ulrich, Henning; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)Modern medicine will unequivocally include regenerative medicine as a major break-through in the re-establishment of damaged or lost tissues due to degenerative diseases or injury. in this scenario, millions of patients worldwide can have their quality of life improved by stem cell implantation coupled with endogenous secretion or administration of survival and differentiation promoting factors. Large efforts, relying mostly on flow cytometry and imaging techniques, have been put into cell isolation, immunophenotyping, and studies of differentiation properties of stem cells of diverse origins. Mesenchymal stem cells (MSCs) are particularly relevant for therapy due to their simplicity of isolation. A minimal phenotypic pattern for the identification of MSCs cells requires them to be immunopositive for CD73, CD90, and CD105 expression, while being negative for CD34, CD45, and HLA-DR and other surface markers. MSCs identified by their cell surface marker expression pattern can be readily purified from patient's bone marrow and adipose tissues. Following expansion and/or predifferentiation into a desired tissue type, stem cells can be reimplanted for tissue repair in the same patient, virtually eliminating rejection problems. Transplantation of MSCs is subject of almost 200 clinical trials to cure and treat a very broad range of conditions, including bone, heart, and neurodegenerative diseases. Immediate or medium term improvements of clinical symptoms have been reported as results of many clinical studies. (C) 2012 International Society for Advancement of Cytometry
- ItemAcesso aberto (Open Access)Indicações de transplante de células-tronco hematopoéticas em pediatria: consenso apresentado no I Encontro de Diretrizes Brasileiras em Transplante de Células-Tronco Hematopoéticas - Sociedade Brasileira de Transplante de Medula Óssea, Rio de Janeiro, 2009(Associação Brasileira de Hematologia e Hemoterapia e Terapia Celular, 2010-01-01) Seber, Adriana [UNIFESP]; Bonfim, Carmem Maria S.; Daudt, Liane E.; Gouveia, Roseane Vasconcelos [UNIFESP]; Ginani, Valéria C. [UNIFESP]; Mauad, Marcos; Castro Jr, Claudio G.; Universidade Federal de São Paulo (UNIFESP); Universidade Federal do Paraná; UFRGS; Hospital Amaral Carvalho; Hospital de Clínicas de Porto AlegreThe Brazilian Bone Marrow Transplant Society (SBTMO) held its First Meeting on Bone Marrow Transplant Guidelines in 2009. A working group of hematologists and oncologists with experience in pediatrics was formed to review evidence-based indications for pediatric transplants. Scientific publications were carefully assessed and, for each disease, the evidence for recommendation (from A to C) and the quality of the evidence (from 1 to 3) were defined. The recommendations include malignant and non-malignant hematological diseases, solid tumors, immunodeficiency, and storage diseases treated with hematopoietic stem cell transplants: either autologous or allogeneic from matched sibling donors or unrelated donors (adults or umbilical cord blood). Guidelines for reduced-intensity transplants, manipulated grafts or partially compatible donors were not included as there are no uniformly accepted recommendations. All indications are based on the best current knowledge which may change over time. Thus, this review should not be directly applied to patient care without taking into account the disease, donor and patient characteristics. Additionally, this paper should not be used as a document to limit patient access to transplant if correctly indicated. In this review we also point out differences between transplantation in adults and children and make some specific recommendations for pediatric transplants.
- ItemAcesso aberto (Open Access)Monocyte transplantation for neural and cardiovascular ischemia repair(Wiley-Blackwell, 2010-03-01) Sanberg, Paul R.; Park, Dong-Hyuk; Kuzmin-Nichols, Nicole; Cruz, Eduardo; Hossne, Nelson Americo [UNIFESP]; Buffolo, Enio [UNIFESP]; Willing, Alison E.; Univ S Florida; Saneron CCEL Therapeut INC; Polo Biotecnol Rio Janeiro; Universidade Federal de São Paulo (UNIFESP)Neovascularization is an integral process of inflammatory reactions and subsequent repair cascades in tissue injury. Monocytes/macrophages play a key role in the inflammatory process including angiogenesis as well as the defence mechanisms by exerting microbicidal and immunomodulatory activity. Current studies have demonstrated that recruited monocytes/macrophages aid in regulating angiogenesis in ischemic tissue, tumours and chronic inflammation. in terms of neovascularization followed by tissue regeneration, monocytes/macrophages should be highly attractive for cell-based therapy compared to any other stem cells due to their considerable advantages: non-oncogenic, non-teratogenic, multiple secretary functions including pro-angiogenic and growth factors, straightforward cell harvesting procedure and non-existent ethical controversy. in addition to adult origins such as bone marrow or peripheral blood, umbilical cord blood (UCB) can be a potential source for autologous or allogeneic monocytes/macrophages. Especially, UCB monocytes should be considered as the first candidate owing to their feasibility, low immune rejection and multiple characteristic advantages such as their anti-inflammatory properties by virtue of their unique immune and inflammatory immaturity, and their proangiogenic ability. in this review, we present general characteristics and potential of monocytes/macrophages for cell-based therapy, especially focusing on neovascularization and UCB-derived monocytes.
- ItemSomente MetadadadosP2X(7)-induced apoptosis decreases by aging in mice myeloblasts(Elsevier B.V., 2007-04-01) Paredes-Gamero, Edgar Julian; Dreyfuss, Juliana Luporini; Nader, Helena B.; Oshiro, Maria Etsuko Miyamoto [UNIFESP]; Ferreira, Alice Teixeira; Universidade Federal de São Paulo (UNIFESP)In the current study, the ability of ATP to promote apoptosis in myeloblasts at different ages was investigated. We have observed that high concentration of extracellular ATP (> 1 mM), which activates P2X(7) receptor, produced cell shrinkage an increase in the number of events in the sub-G(0)/G(1) region of the cellular cycle and annexin-V/propidium iodide label, which characterizes the apoptotic cell death. in addition, BzATP produced apoptosis, but not ADP and UTP. Gr-1(+) cells express the P2X(7) receptor and oxidized ATP, a specific P2X(7) inhibitor, blocked the ATP-dependent apoptosis. ATP-dependent apoptosis is decreased by aging in myeloblasts of 12 and 22-month-old mice. Furthermore, P2X(7) expression decrease was observed in older mice, explaining apoptosis decrease. This decrease in apoptosis by aging may be related to some diseases in the myelocyte lineage. (c) 2007 Published by Elsevier Inc.
- ItemSomente MetadadadosRepair of critical-size bone defects using bone marrow stromal cells: a histomorphometric study in rabbit calvaria. Part I: Use of fresh bone marrow or bone marrow mononuclear fraction(Wiley-Blackwell, 2014-05-01) Pelegrine, Andre Antonio [UNIFESP]; Aloise, Antonio Carlos [UNIFESP]; Zimmermann, Allan [UNIFESP]; Mello e Oliveira, Rafael de [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)ObjectivesThe aim of this study was to compare the bone healing observed after the use of (1) a scaffold enriched with fresh bone marrow, (2) a scaffold enriched with bone marrow mononuclear fraction, and (3) a scaffold alone.Material and methodsTwenty one rabbits were randomly divided into three groups of six animals and 1 group of 3 animals. Bilateral 12-mm diameter defects were created in the animals' parietal bones. in Control Group, the defects were filled with a xenograft alone (n=6); in Group 1, with a xenograft enriched with fresh bone marrow (n=6); in Group 2, with a xenograft enriched with bone marrow mononuclear fraction (n=6) and in Unfilled Group, nothing was grafted (n=3). in Groups 1, 2, and Control, one of the calvarial defects was randomly covered with a barrier membrane. the rabbits were sacrificed 8weeks after surgery, and their parietal bones were harvested and analyzed histomorphometrically.ResultsThe histomorphometric analysis showed no difference between Group 1 and the Control Group regarding non-vital mineralized tissue area, but Group 2 showed a statistically significant higher percentage than the Control Group (P<0.05) for both situations, with membrane (21.24 +/- 3.78% and 13.52 +/- 3.00%, respectively) and without membrane (20.91 +/- 2.01% and 13.08 +/- 1.72%, respectively). Group 2 showed the highest percentage of vital mineralized tissue area, followed by Group 1 and the Control Group (P<0.05) for both situations, with membrane (28.17 +/- 3.19%; 21.14 +/- 7.38% and 13.06 +/- 5.24%, respectively) and without membrane (21.13 +/- 0.55%; 12.45 +/- 6.34% and 6.56 +/- 1.20%, respectively). Group 2 showed the lowest percentage of non-mineralized tissue area, followed by Group 1 and Control Group (P<0.05) for both situations, with membrane (50.59 +/- 6.64%; 58.75 +/- 7.14% and 73.41 +/- 6.87%, respectively) and without membrane (57.97 +/- 1.91%; 71.74 +/- 6.63% and 80.37 +/- 2.67%, respectively). the sides in which the defects were covered with the barrier membrane showed better bone healing compared with the uncovered sides, in all groups (intragroup comparison, P<0.05). the Unfilled Group specimens showed no bone formation.ConclusionsBoth methods using bone marrow stromal cells contributed to enhancing bone healing, especially that using the bone marrow mononuclear fraction. the use of a barrier membrane seemed to have a synergistic effect.
- ItemAcesso aberto (Open Access)Transplante de células-tronco hematopoéticas e leucemia mieloide aguda: diretrizes brasileiras(Associação Brasileira de Hematologia e Hemoterapia e Terapia Celular, 2010-05-01) Silla, Lucia Mariano R.; Dulley, Frederico; Saboya, Rosaura; Paton, Eduardo; Kerbauy, Fábio Rodrigues [UNIFESP]; Arantes, Adriano de Moraes [UNIFESP]; Hamerschlak, Nelson; Hospital de Clínicas de Porto Alegre Serviço de Hematologia e Transplante de Medula Óssea; Universidade de São Paulo (USP); Hospital de Câncer de Barret Hemonúcleo; Universidade Federal de São Paulo (UNIFESP); Associação de Combate ao Câncer em Goiás Hospital Araújo Jorge Serviço de Transplante de Medula Óssea; Hospital Israelita Albert Einstein Programa de Hematologia e Transplante de Medula ÓsseaThe objective of this work was to define guidelines for the indication of hematopoietic stem cells transplantation (HSCT) in the treatment of acute myeloid leukemia (AML) in Brazil. The role of HSCT in the treatment of AML was discussed by the authors and presented to the Brazilian Society of Bone Marrow Transplantation in a meeting to formulate and ratify the Brazilian Guidelines on HSCT. This consensus was based on a review of international publications and on the Brazilian experience in HSCT for the treatment of AML. The optimal treatment for AML in first complete remission (1CR) has not been defined yet. There is consensus on the indication of allogeneic HSCT with myeloablative conditioning for patients who present high risk cytogenetic changes. Allogeneic HSCT is not indicated for low cytogenetic risk 1RC patients and, apparently, allogeneic and autologous HSCT and consolidation chemotherapy are similar for intermediate risk patients.
- ItemSomente MetadadadosXenograft Impregnated with Bone Marrow Mononuclear Fraction for Appositional Bone Regeneration in Rabbit Calvaria: A Clinical and Histomorphometric Study(Quintessence Publishing Co Inc, 2014-07-01) Mello e Oliveira, Rafael de [UNIFESP]; Pelegrine, Andre Antonio [UNIFESP]; Aloise, Antonio Carlos [UNIFESP]; Ferreira, Lydia Masako [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Sao Leopoldo Mandic Inst & Res CtrPurpose: This study investigated the combination of a bone marrow mononuclear fraction with a bone xenograft material in an appositional bone regeneration technique. Materials and Methods: Twelve New Zealand rabbits were randomly divided into two groups of six animals each. Bone reconstruction situations were created using titanium cylinders; these were filled with xenograft in group 1 animals and xenograft enriched with bone marrow mononuclear fraction in group 2 animals. Two cylinders were adapted onto the calvaria of each animal. Bone marrow aspirate was obtained from the tibia of every animal. After 8 weeks, the animals were sacrificed and the parietal bone and cylinders were fixed in 10% formalin for analysis of clinical measurement of the bone volume formed inside the cylinders and histomorphometric evaluation of parameters such as vital mineralized tissue (VMT), nonvital mineralized tissue (NVMT), nonmineralized tissue (NMT), and vital mineralized tissue in contact with titanium (VMTCT). Results: Clinically, groups 1 and 2 demonstrated bone volume gains of 88.29% +/- 25.97% and 98.96% +/- 0.00%, respectively. Histomorphometry for groups 1 and 2, respectively, demonstrated the following mean values: VMT, 18.96% +/- 8.99% and 28.02% +/- 8.76%; NVMT, 28.43% +/- 2.44% and 25.57% +/- 2.33%; NMT, 52.61% +/- 10.80% and 46.42% +/- 10.06%; and VMTCT, 4.98% +/- 4.30% and 27.29% +/- 9.58%. Conclusion: The results of this study suggest that the use of the bone marrow mononuclear fraction can improve bone healing and the level of osseointegration.