15 research outputs found
JAK2 V617F Mutation Prevalence in Myeloproliferative Neoplasms in Pernambuco, Brazil
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Background: The JAK2 V617F mutation is associated with three myeloproliferative neoplasms (MPNs): polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). It generates an unregulated clonal hematopoietic progenitor and leads to abnormal increased proliferation of one or more myeloid lineages. Subjects bearing this mutation may present more frequently with complications such as thrombosis and bleeding, and no specific treatment has yet been developed for BCR-ABL-negative JAK2 V617F-negative MPNs. Aims: To determine the prevalence of JAK2 V617F in MPNs in Pernambuco, Brazil, and to compare it with previous studies. Material and Methods: 144 blood samples were collected at the Hospital of Hematology of the HEMOPE Foundation and were genotyped by polymerase chain reaction-restriction fragment length polymorphism with BsaXI enzymatic digestion. Results and Discussion: 88% (46/52) of the patients with PV, 47% (39/81) with ET, and 77% (8/11) with PMF were positive for JAK2 V617F, while more than 35% of the individuals were JAK2 V617F-negative, confirming a high prevalence of this abnormality in MPNs, more frequently with a low mutated allele burden, similar to what has been reported in other Western countries, despite differences among methods used to detect this mutation. Screening for JAK2 V617F may allow specific management of these diseases with JAK2 inhibitors in the future and highlights the need for further studies on the pathogenesis of BCR-ABL-negative JAK2 V617F-negative MPNs.167802805Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Frequencies of UDP-glucuronosyltransferase 1 (UGT1A1) gene promoter Polymorphisms among distinct ethnic groups from Brazil
A polymorphism in the promoter region of the UDP-glucuronosyltransferase 1 (UGT1A) gene is associated with Gilbert syndrome (GS), a benign form of mild unconjugated hyperbilirubinemia. We genotyped 157 individuals from Brazil, comprising 71 Caucasians, 54 African-derived subjects, and 32 Parakana Indians. Frequencies of the alelle (TA)7 associated with GS found in this study were 0.324, 0.407, and 0.328, respectively. The genotype frequencies differed significantly between Caucasians and African-derived individuals. The high frequencies of (TA)7 polymorphism among the three groups confirm previous data that this polymorphism is very ancient and appears to be distributed throughout the world. (C) 2002 Wiley-Liss, Inc.108211711
Erythropoiesis-driven regulation of hepcidin in human red cell disorders is better reflected through concentrations of soluble transferrin receptor rather than growth differentiation factor 15
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Growth differentiation factor 15 (GDF-15) is a bone marrow-derived cytokine whose ability to suppress iron regulator hepcidin in vitro and increased concentrations found in patients with ineffective erythropoiesis (IE) suggest that hepcidin deficiency mediated by GDF-15 may be the pathophysiological explanation for nontransfusional iron overload. We aimed to compare GDF-15 production in anemic states with different types of erythropoietic dysfunction. Complete blood counts, biochemical markers of iron status, plasma hepcidin, GDF-15, and known hepcidin regulators [interleukin-6 and erythropoietin (EPO)] were measured in 87 patients with red cell disorders comprising IE and hemolytic states: thalassemia, sickle cell anemia, and cobalamin deficiency. Healthy volunteers were also evaluated for comparison. Neither overall increased EPO, nor variable GDF-15 concentrations correlated with circulating hepcidin concentrations (P = 0.265 and P = 0.872). Relative hepcidin deficiency was found in disorders presenting with concurrent elevation of GDF-15 and soluble transferrin receptor (sTfR), a biomarker of erythropoiesis, and sTfR had the strongest correlation with hepcidin (r(S) = -0.584, P < 0.0001). Our data show that high concentrations of GDF-15 in vivo are not necessarily associated with pathological hepcidin reduction, and hepcidin deficiency was only found when associated with sTfR overproduction. sTfR elevation may be a necessary common denominator of erythropoiesis-driven mechanisms to favor iron absorption in anemic states and appears a suitable target for investigative approaches to iron disorders. Am. J. Hematol. 89:385-390, 2014. (c) 2013 Wiley Periodicals, Inc.894385390Instituto Nacional de Ciencia e Tecnologia do Sangue (INCTS)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2008/57441-0
Invasive fungal diseases in haematopoietic cell transplant recipients and in patients with acute myeloid leukaemia or myelodysplasia in Brazil
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Invasive fungal disease (IFD) shows distinct regional incidence patterns and epidemiological features depending on the geographic region. We conducted a prospective survey in eight centres in Brazil from May 2007 to July 2009. All haematopoietic cell transplant (HCT) recipients and patients with acute myeloid leukaemia (AML) or myelodysplasia (MDS) were followed from admission until 1year (HCT) or end of consolidation therapy (AML/MDS). The 12-month cumulative incidence (CI) of proven or probable IFD was calculated, and curves were compared using the Grey test. Among 237 AML/MDS patients and 700 HCT recipients (378 allogeneic, 322 autologous), the 1-year CI of IFD in AML/MDS, allogeneic HCT and autologous HCT was 18.7%, 11.3% and 1.9% (p<0.001), respectively. Fusariosis (23 episodes), aspergillosis (20 episodes) and candidiasis (11 episodes) were the most frequent IFD. The 1-year CI of aspergillosis and fusariosis in AML/MDS, allogeneic HCT and autologous HCT were 13.4%, 2.3% and 0% (p<0.001), and 5.2%, 3.8% and 0.6% (p0.01), respectively. The 6-week probability of survival was 53%, and was lower in cases of fusariosis (41%). We observed a high burden of IFD and a high incidence and mortality for fusariosis in this first multicentre epidemiological study of IFD in haematological patients in Brazil.198745751Pfizer Inc.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [472154/2008-7, 301025/2008-8