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1.
Ann Hematol ; 97(8): 1453-1462, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29623394

RESUMO

The International Myeloma Working Group has proposed the Revised International Staging System (R-ISS) for risk stratification of multiple myeloma (MM) patients. There are a limited number of studies that have validated this risk model in the autologous stem cell transplant (ASCT) setting. In this retrospective study, we evaluated the applicability and value for predicting survival of the R-ISS model in 134 MM patients treated with new agents and ASCT at the Mayo Clinic in Arizona and the University Hospital of Salamanca in Spain. The patients were reclassified at diagnosis according to the R-ISS: 44 patients (33%) had stage I, 75 (56%) had stage II, and 15 (11%) had stage III. After a median follow-up of 60 months, R-ISS assessed at diagnosis was an independent predictor for overall survival (OS) after ASCT, with median OS not reached, 111 and 37 months for R-ISS I, II and III, respectively (P < 0.001). We also found that patients belonging to R-ISS II and having high-risk chromosomal abnormalities (CA) had a significant shorter median OS than those with R-ISS II without CA: 70 vs. 111 months, respectively. Therefore, this study lends further support for the R-ISS as a reliable prognostic tool for estimating survival in transplant myeloma patients and suggests the importance of high-risk CA in the R-ISS II group.


Assuntos
Mieloma Múltiplo/diagnóstico , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Biomarcadores , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Quimioterapia de Indução , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento
3.
Am J Hematol ; 92(5): 467-472, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28230270

RESUMO

Patients with indolent non-Hodgkin lymphoma (NHL) have multiple treatment options yet there is no consensus as to the best initial therapy. Lenalidomide, an immunomodulatory agent, has single agent activity in relapsed lymphoma. This trial was conducted to assess feasibility, efficacy, and safety of adding lenalidomide to rituximab, cyclophosphamide, and dexamethasone (LR-CD) in untreated indolent NHL patients requiring therapy. This was a single institution phase II trial. Treatment consisted of IV rituximab 375 mg/m2 day 1; oral lenalidomide 20 mg days 1-21; cyclophosphamide 250 mg/m2 days 1, 8, and 15; and dexamethasone 40 mg days 1, 8, 15, and 22 of a 28-day cycle. Treatment continued 2 cycles beyond best response for a maximum of 12 cycles without rituximab maintenance. Thirty-three patients were treated. Median age was 68 (43-83 years). 39% had stage IV disease. Histologic subtypes included 8 follicular lymphoma (FL), 7 marginal zone lymphoma (MZL) (1 splenic, 2 extranodal, and 4 nodal), 15 Waldenström's macroglobulinemia (WM), 1 lymphoplasmacytic lymphoma, 1 small lymphocytic lymphoma, and 1 low-grade B-cell lymphoma with plasmacytic differentiation (unable to be classified better as MZL or LPL). Hematologic toxicity was the most common adverse event. Median time of follow-up was 23.4 months (range 1.8-50.9). The overall response rate was 87.9%, with 30.3% complete response. The median duration of response was 38.7 months. The median progression free survival was 39.7 months, while median overall survival (OS) has not yet been reached. Lenalidomide can be safely added to a simple regimen of rituximab, oral cyclophosphamide, and dexamethasone and is an effective combination as initial therapy for low-grade B-cell NHL.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Lenalidomida , Linfoma de Células B/tratamento farmacológico , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Rituximab/administração & dosagem , Análise de Sobrevida , Talidomida/administração & dosagem , Talidomida/análogos & derivados , Resultado do Tratamento
4.
Br J Haematol ; 173(6): 876-83, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26999424

RESUMO

Pure red cell aplasia (PRCA) is a rare disorder characterized by inhibition of erythroid precursors in the bone marrow and normochromic, normocytic anaemia with reticulocytopenia. Among 51 PRCA patients, we identified 12 (24%) patients having monoclonal gammopathy, monoclonal gammopathy of undetermined significance or smouldering multiple myeloma, with presence of monoclonal protein or abnormal serum free light chains and atypical bone marrow features of clonal plasmacytosis, hypercellularity and fibrosis. Thus far, three patients treated with anti-myeloma based therapeutics have responded with reticulocyte recovery and clinical transfusion independence, suggesting plasma cells play a key role in the pathogenesis of this specific monoclonal gammopathy-associated PRCA.


Assuntos
Mieloma Múltiplo/diagnóstico , Paraproteinemias/diagnóstico , Aplasia Pura de Série Vermelha/diagnóstico , Adulto , Idoso , Medula Óssea/patologia , Dexametasona/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Imunoglobulinas/sangue , Lenalidomida , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Paraproteinemias/patologia , Plasmócitos/fisiologia , Aplasia Pura de Série Vermelha/patologia , Contagem de Reticulócitos , Reticulócitos/fisiologia , Talidomida/análogos & derivados , Talidomida/uso terapêutico , Adulto Jovem
5.
J Allergy Clin Immunol ; 134(1): 178-87, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24582309

RESUMO

BACKGROUND: Mastocytosis associated with germline KIT activating mutations is exceedingly rare. We report the unique clinicopathologic features of a patient with systemic mastocytosis caused by a de novo germline KIT K509I mutation. OBJECTIVES: We sought to investigate the effect of the germline KIT K509I mutation on human mast cell development and function. METHODS: Primary human mast cells derived from CD34(+) peripheral blood progenitors were examined for growth, development, survival, and IgE-mediated activation. In addition, a mast cell transduction system that stably expressed the KIT K509I mutation was established. RESULTS: KIT K509I biopsied mast cells were round, CD25(-), and well differentiated. KIT K509I progenitors cultured in stem cell factor (SCF) demonstrated a 10-fold expansion compared with progenitors from healthy subjects and developed into mature hypergranular mast cells with enhanced antigen-mediated degranulation. KIT K509I progenitors cultured in the absence of SCF survived but lacked expansion and developed into hypogranular mast cells. A KIT K509I mast cell transduction system revealed SCF-independent survival to be reliant on the preferential splicing of KIT at the adjacent exonic junction. CONCLUSION: Germline KIT mutations associated with mastocytosis drive a well-differentiated mast cell phenotype distinct to that of somatic KIT D816V disease, the oncogenic potential of which might be influenced by SCF and selective KIT splicing.


Assuntos
Mutação em Linhagem Germinativa , Mastócitos/patologia , Mastocitose Sistêmica/genética , Fenótipo , Proteínas Proto-Oncogênicas c-kit/genética , Adulto , Processamento Alternativo , Degranulação Celular/efeitos dos fármacos , Diferenciação Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Feminino , Expressão Gênica , Humanos , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Mastocitose Sistêmica/imunologia , Mastocitose Sistêmica/patologia , Fator de Células-Tronco/farmacologia , Transdução Genética
6.
Biol Blood Marrow Transplant ; 20(9): 1375-81, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24867778

RESUMO

Although allogeneic hematopoietic cell transplantation (HCT) is an expensive treatment for hematological disorders, little is known about the financial consequences for the patients who undergo this procedure. We analyzed factors associated with its financial burden and its impact on health behaviors of allogeneic HCT recipients. A questionnaire was retrospectively mailed to 482 patients who underwent allogeneic HCT from January 2006 to June 2012 at the Mayo Clinic, to collect information regarding current financial concerns, household income, employment, insurance, out-of-pocket expenses, and health and functional status. A multivariable logistic regression analysis identified factors associated with financial burden and treatment nonadherence. Of the 268 respondents (56% response rate), 73% reported that their sickness had hurt them financially. All patients for whom the insurance information was available (missing, n = 13) were insured. Forty-seven percent of respondents experienced financial burden, such as household income decreased by >50%, selling/mortgaging home, or withdrawing money from retirement accounts. Three percent declared bankruptcy. Younger age and poor current mental and physical functioning increased the likelihood of financial burden. Thirty-five percent of patients reported deleterious health behaviors because of financial constraints. These patients were likely to be younger, have lower education, and with a longer time since HCT. Being employed decreased the likelihood of experiencing financial burden and treatment nonadherence due to concern about costs. A significant proportion of allogeneic HCT survivors experience financial hardship despite insurance coverage. Future research should investigate potential interventions to help at-risk patients and prevent adverse financial outcomes after this life-saving procedure.


Assuntos
Transplante de Células-Tronco Hematopoéticas/economia , Condicionamento Pré-Transplante/economia , Transplante Homólogo/economia , Adolescente , Adulto , Idoso , Feminino , Humanos , Cobertura do Seguro , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários , Adulto Jovem
7.
J Math Biol ; 69(6-7): 1627-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24366372

RESUMO

Dynamics on networks is considered from the perspective of Markov stochastic processes. We partially describe the state of the system through network motifs and infer any missing data using the available information. This versatile approach is especially well adapted for modelling spreading processes and/or population dynamics. In particular, the generality of our framework and the fact that its assumptions are explicitly stated suggests that it could be used as a common ground for comparing existing epidemics models too complex for direct comparison, such as agent-based computer simulations. We provide many examples for the special cases of susceptible-infectious-susceptible and susceptible-infectious-removed dynamics (e.g., epidemics propagation) and we observe multiple situations where accurate results may be obtained at low computational cost. Our perspective reveals a subtle balance between the complex requirements of a realistic model and its basic assumptions.


Assuntos
Doenças Transmissíveis/epidemiologia , Epidemias , Cadeias de Markov , Dinâmica Populacional , Simulação por Computador , Humanos , Modelos Teóricos
8.
Curr Opin Hematol ; 20(2): 157-62, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23385615

RESUMO

PURPOSE OF REVIEW: In 2012, idiopathic hypereosinophilic syndrome (HES) is still the prevalent diagnosis in patients with persistent eosinophilia, in which a primary or secondary cause of eosinophilia has not been identified. HES is considered a provisional diagnosis until a primary or secondary cause of hypereosinophilia is established. The discovery of imatinib-sensitive fusion proteins in a subset of patients with hypereosinophilia has changed the way we approach the diagnosis and treatment of eosinophilic myeloid neoplasms [eosinophilic myeloproliferative neoplasms (MPNs)]. Despite the recent diagnostic developments, diagnosis of hypereosinophilic MPN is only made in 10-20% of patients with persistent primary hypereosinophilia. RECENT FINDINGS: In 2008 the World Health Organization (WHO) established a semi-molecular classification of hypereosinophilic MPNs. The discovery of PDGFRA, PDGFRB, FGFR1, JAK-2, and FLT3 fusion proteins in patients with eosinophilic MPNs provide opportunities for targeted therapy. Patients with hypereosinophilic MPNs associated with PDGFRA and PDGFRB fusion genes are responsive to imatinib. SUMMARY: Ongoing research continues to expand our understanding of the pathophysiology of persistent primary hypereosinophilia and clarify the boundaries between some of these disorders. A key challenge is to identify new targets for therapy and limit the number of patients who are classified as having HES.


Assuntos
Síndrome Hipereosinofílica/diagnóstico , Transtornos Mieloproliferativos/diagnóstico , Eosinofilia/metabolismo , Humanos , Síndrome Hipereosinofílica/metabolismo , Transtornos Mieloproliferativos/metabolismo , Proteínas Tirosina Quinases/metabolismo
9.
Biol Blood Marrow Transplant ; 19(8): 1167-74, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23664940

RESUMO

Although reduced-intensity conditioning has become standard of care for patients with hematologic malignancies undergoing allogeneic hematopoietic cell transplantation (HCT), the optimum regimen has yet to be defined, and may depend on pretransplantation patient- and/or disease-specific risk factors. We report here results in 100 adults, ages 18 to 69, with high-risk hematologic malignancy who received conditioning with fludarabine, carmustine, melphalan, and rabbit antithymocyte globulin (FBM-A). Outcomes were stratified using the disease risk index (DRI) as published by Armand et al. (Blood 2012;120:905-913). Median age was 56, and patients were ineligible for standard myeloablative conditioning because of age, organ dysfunction, or prior autologous HCT. Patients underwent transplantation for myeloid (acute myelogenous leukemia, n = 40; myelodysplastic syndrome, n = 24; myelofibrosis, n = 13; other myeloid, n = 2) or lymphoid (acute lymphoblastic leukemia, n = 8; non-Hodgkin lymphoma, n = 8; Hodgkin lymphoma, n = 4, chronic lymphocytic leukemia, n = 1) malignancy. Donors were related in 26 patients (22 matched, 4 mismatched at 1 antigen) and unrelated in 74 (mismatched at 1 or 2 HLA loci in 33); grafts were peripheral blood stem cells in 97 patients, bone marrow in 2, and double cord in 1. According to the DRI, 68 patients were classified as low (n = 1) or intermediate risk (n = 67), and 32 were classified as high (n = 28) or very high risk (n = 4). With a median follow-up of surviving patients of 18 months, the Kaplan-Meier estimate of overall survival at 2 years for patients in the low/intermediate risk group is 80%, compared with 66% in the high/very high group (P = .11). Two-year cumulative incidence of relapse and nonrelapse mortality in the low/intermediate group are 9.9% and 15%, versus 25% and 19% in the high/very high group (respective P values .07 and .81). The cumulative incidence of acute graft-versus-host (GVHD) grades III to IV at 100 days was 8.1%, and the incidence of National Institutes of Health-defined moderate to severe chronic GVHD was 22% at 2 years. No deaths were attributable to chronic GVHD. Survival was not influenced by age, hematopoietic comorbidity index score, donor type, donor gender, or presence of mismatch. We conclude that FBM-A is an effective and safe conditioning regimen for adults up to age 69 with hematologic malignancies who have low-, intermediate-, or high-risk scores according to the DRI.


Assuntos
Soro Antilinfocitário/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Melfalan/uso terapêutico , Condicionamento Pré-Transplante/métodos , Adulto , Fatores Etários , Idoso , Soro Antilinfocitário/administração & dosagem , Soro Antilinfocitário/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carmustina/administração & dosagem , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/cirurgia , Humanos , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Quimeras de Transplante , Transplante Homólogo , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Adulto Jovem
10.
Blood ; 117(13): 3629-40, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21273305

RESUMO

Activating mutations in codon D816 of the tyrosine kinase receptor, KIT, are found in the majority of patients with systemic mastocytosis. We found that the transcription factor, microphthalmia-associated transcription factor (MITF), is highly expressed in bone marrow biopsies from 9 of 10 patients with systemic mastocytosis and activating c-KIT mutations. In primary and transformed mast cells, we show that KIT signaling markedly up-regulates MITF protein. We demonstrate that MITF is required for the proliferative phenotype by inhibiting colony-forming units with sh-RNA knockdown of MITF. Furthermore, constitutively active KIT does not restore growth of primary MITF-deficient mast cells. MITF mRNA levels do not change significantly with KIT signaling, suggesting posttranscriptional regulation. An array screen from mast cells identified candidate miRNAs regulated by KIT signaling. We found that miR-539 and miR-381 are down-regulated by KIT signaling and they repressed MITF expression through conserved miRNA binding sites in the MITF 3'-untranslated region. Forced expression of these miRNAs suppressed MITF protein and inhibited colony-forming capacity of mastocytosis cell lines. This work demonstrates a novel regulatory pathway between 2 critical mast cell factors, KIT and MITF, mediated by miRNAs; dysregulation of this pathway may contribute to abnormal mast cell proliferation and malignant mast cell diseases.


Assuntos
Proliferação de Células , Mastócitos/patologia , Mastócitos/fisiologia , MicroRNAs/fisiologia , Fator de Transcrição Associado à Microftalmia/genética , Proteínas Proto-Oncogênicas c-kit/fisiologia , Animais , Antineoplásicos/farmacologia , Benzamidas , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Mastocitose Sistêmica/genética , Mastocitose Sistêmica/metabolismo , Mastocitose Sistêmica/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , Fator de Transcrição Associado à Microftalmia/metabolismo , Células NIH 3T3 , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia
11.
Phys Rev Lett ; 111(7): 078701, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23992086

RESUMO

Controlling self-organizing systems is challenging because the system responds to the controller. Here, we develop a model that captures the essential self-organizing mechanisms of Bak-Tang-Wiesenfeld (BTW) sandpiles on networks, a self-organized critical (SOC) system. This model enables studying a simple control scheme that determines the frequency of cascades and that shapes systemic risk. We show that optimal strategies exist for generic cost functions and that controlling a subcritical system may drive it to criticality. This approach could enable controlling other self-organizing systems.

12.
Blood ; 116(15): 2793-802, 2010 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-20616219

RESUMO

Mutations in more than 15 genes are now known to cause severe congenital neutropenia (SCN); however, the pathologic mechanisms of most genetic defects are not fully defined. Deficiency of G6PC3, a glucose-6-phosphatase, causes a rare multisystem syndrome with SCN first described in 2009. We identified a family with 2 children with homozygous G6PC3 G260R mutations, a loss of enzymatic function, and typical syndrome features with the exception that their bone marrow biopsy pathology revealed abundant neutrophils consistent with myelokathexis. This pathologic finding is a hallmark of another type of SCN, WHIM syndrome, which is caused by gain-of-function mutations in CXCR4, a chemokine receptor and known neutrophil bone marrow retention factor. We found markedly increased CXCR4 expression on neutrophils from both our G6PC3-deficient patients and G6pc3(-/-) mice. In both patients, granulocyte colony-stimulating factor treatment normalized CXCR4 expression and neutrophil counts. In G6pc3(-/-) mice, the specific CXCR4 antagonist AMD3100 rapidly reversed neutropenia. Thus, myelokathexis associated with abnormally high neutrophil CXCR4 expression may contribute to neutropenia in G6PC3 deficiency and responds well to granulocyte colony-stimulating factor.


Assuntos
Glucose-6-Fosfatase/genética , Doença de Depósito de Glicogênio Tipo I/genética , Neutropenia/congênito , Neutropenia/genética , Receptores CXCR4/genética , Adolescente , Animais , Criança , Feminino , Expressão Gênica , Homozigoto , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação de Sentido Incorreto , Neutropenia/enzimologia , Neutrófilos/metabolismo , Síndrome
13.
Am J Hematol ; 87(5): 562-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22460584

RESUMO

Immediately after the annual scientific meeting of the American Society of Hematology (ASH), a select group of clinical and laboratory investigators in myeloproliferative neoplasms (MPN) is summoned to a post-ASH conference on chronic myeloid leukemia and the BCR-ABL1-negative MPN. The 6th such meeting occurred on December 13­14,2011, in La Jolla, California, USA, under the direction of its founder,Dr. Tariq Mughal. The current document is the first of two reports on this post-ASH event and summarizes the most recent preclinical and clinical advances in polycythemia vera, essential thrombocythemia,and primary myelofibrosis.


Assuntos
Genes Neoplásicos , Transtornos Mieloproliferativos/genética , Ensaios Clínicos como Assunto , Metilação de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , Progressão da Doença , Drogas em Investigação/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/patologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Inflamação , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Estudos Multicêntricos como Assunto , Transtornos Mieloproliferativos/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Polietilenoglicóis/uso terapêutico , Prognóstico , Proteínas Recombinantes/uso terapêutico , Talidomida/análogos & derivados , Talidomida/uso terapêutico , Resultado do Tratamento
14.
Haematologica ; 96(8): 1221-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21508125

RESUMO

A novel, genetic immunodeficiency syndrome has been recently described, herein termed "MonoMAC". It is characterized by severe circulating monocytopenia, NK- and B-lymphocytopenia, severe infections with M. avium complex (MAC), and risk of progression to myelodysplasia/acute myelogenous leukemia. Detailed bone marrow analyses performed on 18 patients further define this disorder. The majority of patients had hypocellular marrows with reticulin fibrosis and multilineage dysplasia affecting the myeloid (72%), erythroid (83%) and megakaryocytic (100%) lineages. Cytogenetic abnormalities were present in 10 of 17 (59%). Despite B-lymphocytopenia, plasma cells were present but were abnormal (e.g. CD56(+)) in nearly half of cases. Increased T-cell large granular lymphocyte populations were present in 28% of patients. Chromosomal breakage studies, cell cycle checkpoint functions, and sequencing of TERT and K-RAS genes revealed no abnormalities. MonoMAC appears to be a unique, inherited syndrome of bone marrow failure. We describe distinctive bone marrow features to help in its recognition and diagnosis. (Clinicaltrials.gov identifiers: NCT00018044, NCT00923364, NCT01212055).


Assuntos
Síndromes de Imunodeficiência/diagnóstico , Leucopenia/patologia , Monócitos/patologia , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Análise Citogenética , Progressão da Doença , Feminino , Instabilidade Genômica/genética , Humanos , Síndromes de Imunodeficiência/complicações , Imunofenotipagem , Leucemia Mieloide Aguda/patologia , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Síndromes Mielodisplásicas/complicações , Mielofibrose Primária/patologia , Risco , Adulto Jovem
15.
Phys Rev Lett ; 107(15): 158702, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-22107326

RESUMO

We introduce a mechanism which models the emergence of the universal properties of complex networks, such as scale independence, modularity and self-similarity, and unifies them under a scale-free organization beyond the link. This brings a new perspective on network organization where communities, instead of links, are the fundamental building blocks of complex systems. We show how our simple model can reproduce social and information networks by predicting their community structure and more importantly, how their nodes or communities are interconnected, often in a self-similar manner.


Assuntos
Redes Comunitárias , Serviços de Informação , Modelos Teóricos
16.
Pediatr Blood Cancer ; 56(1): 103-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21108444

RESUMO

BACKGROUND: Treatment-associated fetal hemoglobin (HbF) expression patterns in children with sickle cell disease (SCD) have not been fully described. The objective of this study was to compare HbF expression profiles (HbF and F-cells) in the peripheral blood of pediatric SCD patients receiving hydroxyurea (HU), chronic transfusions (Tx) or no chronic therapy (Ctrl). PROCEDURE: Peripheral blood samples were collected from SCD patients between 1 month and 21 years of age and immunostained with anti-HbF and anti-HbA antibodies. Erythrocytes containing HbF (F-cells) were enumerated with this dual staining method. HbF was measured using chromatography (HPLC). RESULTS: Blood from 44 Ctrl patients ≤ 4 years of age was compared with that from older children (50 Ctrl, 17 HU, 17 Tx). Among the older children, the percentage of both HbF and F-cells in the Tx group was significantly decreased compared to the control (HbF 5.4 ± 4.2% vs. 11.0 ± 7.2%, P = 0.003; F-cells 30.2 ± 16.3% vs. 43.8 ± 20.4%, P = 0.0071). While the distribution of F-cells was significantly increased in the HU group (56.3 ± 17.1% vs. 43.8 ± 20.4%, P = 0.016), the increase in HbF was less robust (14.7 ± 6.4% vs. 11.0 ± 7.2%, P = 0.051). Positive correlations of HbF and F-cell distributions were noted in all groups (P < 0.0001 for all groups). In serial samples from individual patients, relatively static patterns of HbF and F-cell distribution were noted. CONCLUSION: Pediatric SCD patients possess distinct patterns of HbF switching and silencing in peripheral blood erythrocytes. Thereafter, erythrocyte HbF expression level and distribution are maintained with both patient- and treatment-specific patterns that may be useful for predicting the need or response to HbF-modulating therapy.


Assuntos
Anemia Falciforme/sangue , Eritrócitos Anormais/patologia , Hemoglobina Fetal/análise , Adolescente , Anemia Falciforme/terapia , Transfusão de Sangue , Criança , Pré-Escolar , Contagem de Eritrócitos , Humanos , Hidroxiureia/uso terapêutico , Lactente , Adulto Jovem
17.
Curr Opin Hematol ; 17(3): 184-90, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20182355

RESUMO

PURPOSE OF REVIEW: Growth differentiation factor 15 (GDF15) was identified as a hepcidin-suppression factor that is expressed at high levels in patients with ineffective erythropoiesis. This review addresses the regulation, expression and potential functions of GDF15 in the context of erythroid biology. RECENT FINDINGS: GDF15 expression during late erythroid differentiation was discovered as part of an erythroblast transcriptome project. As GDF15 expression is associated with cellular stress or apoptosis, further investigation of the cytokine was focused upon its involvement in ineffective erythropoiesis. Remarkably high serum levels were detected in patients with thalassemia syndromes, congenital dyserythropoiesis and some acquired sideroblastic anemias. High-level GDF15 expression is not a feature of normal erythropoiesis, or erythroid recovery after bone-marrow transplantation. As GDF15 is a transforming growth factor-beta superfamily member, it was investigated as an effector of ineffective erythropoiesis that suppresses hepcidin expression despite iron overloading. SUMMARY: In contrast to the low levels of GDF15 expressed during normal erythropoiesis, ineffective erythropoiesis causes high-level expression of GDF15. In patients with thalassemia and related anemias, GDF15 expression may contribute to iron overloading or other features of the disease phenotype.


Assuntos
Anemia/metabolismo , Eritropoese/fisiologia , Fator 15 de Diferenciação de Crescimento/metabolismo , Sobrecarga de Ferro/metabolismo , Talassemia/metabolismo , Anemia/patologia , Animais , Humanos , Sobrecarga de Ferro/patologia , Talassemia/patologia
18.
Sci Adv ; 6(50)2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33298450

RESUMO

Li-10 wt % Mg alloy (Li-10 Mg) is used as an anode material for a solid-state battery with excellent electrochemical performance and no evidence of dendrite formation during cycling. Thermal treatment of Li metal during manufacturing improves the interfacial contact between a Li metal electrode and solid electrolyte to achieve an all solid-state battery with increased performance. To understand the properties of the alloy passivation layer, this paper presents the first direct observation of its evolution at elevated temperatures (up to 325°C) by in situ scanning electron microscopy. We found that the morphology of the surface passivation layer was unchanged above the alloy melting point, while the bulk of the material below the surface was melted at the expected melting point, as confirmed by in situ electron backscatter diffraction. In situ heat treatment of Li-based materials could be a key method to improve battery performance.

19.
Leuk Lymphoma ; 61(8): 1996-2002, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32281491

RESUMO

Anti-thymocyte globulin (ATG) has been associated with decreased rates graft versus host disease (GVHD) but with a potential risk of increasing risk of infection and relapse. We retrospectively studied the impact of single dose low dose (2.5 mg/kg) ATG in patients undergoing allogenic hematopoietic cell transplantation (HCT) from 8/8 matched unrelated donors (MUD). Of the total 209 patients identified, 129 received ATG. At baseline, the ATG group had more intermediate and high disease risk index (DRI) (64.6% vs. 54.3%) (28.3% vs. 23.7%) p < .001, respectively, and who received reduced intensity or non-myeloablative conditioning (RIC) (69.0% vs. 47.5%, p .003). There was no significant difference in the overall survival (OS) HR = 1.3, 95% CI [0.99, 1.0], p = .350 or relapse-free survival (RFS) HR = 1.2, 95% CI [0.74, 1.8], p = .526 between the two groups. Patients receiving ATG had a lower incidence of chronic GVHD (cGVHD) (10.1% vs. 25%, p = .007) and less moderate to severe cGVHD (8.5% vs. 25%, p = .002). ATG was associated with a reduced incidence of moderate to severe cGVHD OR = 0.28, 95% CI [0.12, 0.61], p < .01. There was no difference in the incidence of Epstein-Barr Virus (EBV) or cytomegalovirus (CMV) reactivation, CMV disease, invasive fungal infection, or grade III-IV acute GVHD (aGVHD). Our study shows that low dose ATG results in similar OS and RFS with lower rates of cGVHD. Additional prospective studies are needed to confirm these findings.


Assuntos
Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Soro Antilinfocitário , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4 , Humanos , Recidiva Local de Neoplasia , Estudos Prospectivos , Estudos Retrospectivos , Condicionamento Pré-Transplante , Doadores não Relacionados
20.
Blood Cancer J ; 10(3): 36, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32157091

RESUMO

Factors predicting allogeneic hematopoietic cell transplantation (HCT) outcomes in myelofibrosis in the early post-HCT period have not been defined thus far. We attempt to study such factors that can help identify patients at a higher risk of relapse or death. This retrospective study included 79 patients who underwent first HCT for myelofibrosis at three centers between 2005 and 2016. Univariate analysis showed that red blood cell (RBC) transfusion dependence (HR 9.02, 95% CI 4.0-20.35), platelet transfusion dependence (HR 8.17, 95%CI 3.83-17.37), 100% donor chimerism in CD33 + cells (HR 0.21, 95%CI 0.07-0.62), unfavorable molecular status (HR 4.41, 95%CI 1.87-10.39), normal spleen size (HR 0.42, 95%CI 0.19-0.94), grade ≥ 2 bone marrow fibrosis (vs. grade ≤ 1; HR 2.7, 95%CI 1.1-6.93) and poor graft function (HR 2.6, 95%CI 1.22-5.53) at day +100 were statistically significantly associated with relapse-free survival (RFS). RBC transfusion dependence and unfavorable molecular status were also statistically significant in the multivariate analysis. Patients in whom both of these factors were present had a significantly worse RFS when compared to those with one or none. While limited by a small sample size, we demonstrate the significance of transfusion dependence and molecular status at day +100 in predicting outcomes.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Mielofibrose Primária/mortalidade , Condicionamento Pré-Transplante/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/terapia , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
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