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1.
Leukemia ; 26(7): 1638-46, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22222599

RESUMO

We performed an immunogenetic analysis of 345 IGHV-IGHD-IGHJ rearrangements from 337 cases with primary splenic small B-cell lymphomas of marginal-zone origin. Three immunoglobulin (IG) heavy variable (IGHV) genes accounted for 45.8% of the cases (IGHV1-2, 24.9%; IGHV4-34, 12.8%; IGHV3-23, 8.1%). Particularly for the IGHV1-2 gene, strong biases were evident regarding utilization of different alleles, with 79/86 rearrangements (92%) using allele (*)04. Among cases more stringently classified as splenic marginal-zone lymphoma (SMZL) thanks to the availability of splenic histopathological specimens, the frequency of IGHV1-2(*)04 peaked at 31%. The IGHV1-2(*)04 rearrangements carried significantly longer complementarity-determining region-3 (CDR3) than all other cases and showed biased IGHD gene usage, leading to CDR3s with common motifs. The great majority of analyzed rearrangements (299/345, 86.7%) carried IGHV genes with some impact of somatic hypermutation, from minimal to pronounced. Noticeably, 75/79 (95%) IGHV1-2(*)04 rearrangements were mutated; however, they mostly (56/75 cases; 74.6%) carried few mutations (97-99.9% germline identity) of conservative nature and restricted distribution. These distinctive features of the IG receptors indicate selection by (super)antigenic element(s) in the pathogenesis of SMZL. Furthermore, they raise the possibility that certain SMZL subtypes could derive from progenitor populations adapted to particular antigenic challenges through selection of VH domain specificities, in particular the IGHV1-2(*)04 allele.


Assuntos
Regiões Determinantes de Complementaridade/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Cadeia Pesada de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Linfoma de Zona Marginal Tipo Células B/genética , Neoplasias Esplênicas/genética , Estudos de Coortes , Humanos , Modelos Moleculares , Mutação/genética , Prognóstico
2.
Acta Haematol ; 126(1): 54-62, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21474922

RESUMO

BACKGROUND/AIMS: Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) share the same acquired lesion JAK2(V617F) and may exhibit substantial overlap. Variability in JAK activation and allele burden, complemented by host, genetic and non-genetic modifiers, determine the phenotype. The aim of this study was to investigate the presence of the JAK2 mutation in association with the ratio of metallopeptidases inhibitors (TIMPs) to tissue metallopeptidases (MMPs) in MPNs, where inhibitory rather than proteolytic activity in marrow microenvironment appears to predominate. METHODS: 94 patients with polycythemia vera, essential thrombocythemia and primary myelofibrosis, and 102 healthy individuals were evaluated. Allele-specific PCR and RFLP were used to detect JAK2 and genomic status. Serum concentrations of MMP and TIMP were measured by ELISA. The parameters were assessed with covariance analysis, and adjusted for gender, age and co-morbidity. RESULTS: Mutation frequency was 81.91%. Abnormal TIMP/MMP ratios were identified in all three diseases. JAK2 mutation was correlated with significant changes in TIMP concentrations. CONCLUSIONS: Identification of an abnormal TIMP/MMP ratio in all three diseases, regardless of the JAK2 status, indicates invariable marrow remodeling. In this particular group of patients, presence of a JAK2(V617F) mutation, being associated with even higher ratios, appears to be a concurring participant in bone marrow-reforming processes. Additional research may delineate correlates with the JAK2 allelic burden.


Assuntos
Genes abl , Janus Quinase 2/genética , Metaloproteinases da Matriz/metabolismo , Mutação , Transtornos Mieloproliferativos/metabolismo , Inibidores de Proteases/farmacologia , Idoso , Feminino , Humanos , Hidrólise , Masculino , Inibidores de Metaloproteinases de Matriz , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/genética
3.
Int J Cardiol ; 134(2): 207-11, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18559286

RESUMO

BACKGROUND: Cardiovascular complications are common in beta-thalassemia major (beta-TM), mainly attributed to increased cardiac iron depositions. Early cardiovascular involvement in patients without cardiac symptoms and without cardiac iron overload has not been adequately investigated. METHODS: Twenty six patients (11 males) with beta-TM, on chelation therapy, age 23+/-4 years without cardiac iron overload (measured by magnetic resonance imaging), and 30 age and gender matched healthy controls were included in the study. Carotid-femoral and carotid-radial pulse wave velocity (PWVc-f and PWVc-r) and augmentation index (AI) were measured by SphygmoCor device; carotid intima-media thickness; left ventricular (LV) dimensions and function; left atrial (LA) volume and function were assessed by echocardiography. RESULTS: Patients with beta-TM had higher PWVc-f (8.4+/-1.4 vs 7.2+/-1.1 m/s, p=0.002) and augmentation index (21.7+/-10.9 vs 14.7+/-9.7%, p=0.04) indicating decreased aortic elastic properties; greater LV mass index (72.0+/-13.3 vs 63.8+/-11.5 g/m(2), p=0.04) and greater LA volumes. Multivariate logistic regression analysis revealed that higher PWVc-f was independently associated with higher LV mass [OR 1.74 95%CI (1.09-2.88), p=0.026]; and greater LA dimensions [OR 1.68 95%CI (1.04-2.72), p=0.035]. CONCLUSIONS: In the absence of cardiac iron overload, asymptomatic patients with beta-TM demonstrated aortic stiffening associated with increased LV mass and LA enlargement. These alterations may represent signs of early cardiovascular involvement.


Assuntos
Doenças da Aorta , Hipertrofia Ventricular Esquerda , Talassemia beta/complicações , Adulto , Aorta/diagnóstico por imagem , Aorta/patologia , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etiologia , Doenças da Aorta/patologia , Velocidade do Fluxo Sanguíneo , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/patologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Ecocardiografia , Elasticidade , Feminino , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/patologia , Sobrecarga de Ferro , Modelos Lineares , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Fluxo Pulsátil , Artéria Radial/diagnóstico por imagem , Artéria Radial/patologia , Adulto Jovem
4.
Leukemia ; 23(3): 510-8, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19020538

RESUMO

CD4(+)CD25(+)FOXP3(+) T regulatory cells (T(regs)) prevent autoimmunity by restricting overexuberant immune responses, but the same subpopulation can incur detrimental effects on antitumor responses. In both cases, the suppressor potential of T(regs) appears to be strongly influenced by their compartmentalization. In myelodysplastic syndromes (MDS), immune deregulation and autoimmunity in the early stages might lead to ineffective hematopoiesis and bone marrow (BM) failure, whereas late-stage disease is characterized by the immune escape of the malignant clone. We show that these two stages of MDS are associated with differential T(reg) activity. Specifically, we found that in early stage MDS, compared with normal hematopoiesis and late stage MDS, T(regs) are dysfunctional and their BM homing through the CXCL12/CXCR4 axis is seriously impaired as a result of CXCR4 downregulation. Conversely, in late stage MDS, T(regs) are systemically and locally expanded and retain their function and migratory capacity. Moreover, T(reg) levels follow the disease course and are significantly reduced in treatment responding patients. Our findings indicate T(reg) involvement in the pathophysiology of MDS; defective suppressor function and BM trafficking of T(regs) may be important in the autoimmune process of early MDS, but increased T(reg) activity could favor leukemic clone progression in late stage disease.


Assuntos
Medula Óssea/patologia , Quimiocina CXCL12/fisiologia , Síndromes Mielodisplásicas/patologia , Receptores CXCR4/fisiologia , Receptores de Retorno de Linfócitos/fisiologia , Linfócitos T Reguladores/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoimunidade , Células Sanguíneas/patologia , Medula Óssea/imunologia , Divisão Celular , Transformação Celular Neoplásica/imunologia , Quimiotaxia de Leucócito , Células Clonais/patologia , Progressão da Doença , Feminino , Humanos , Vigilância Imunológica , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/imunologia , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/fisiopatologia , Células-Tronco Neoplásicas/patologia , Receptores CXCR4/genética , Linfócitos T Reguladores/imunologia
5.
Leuk Res ; 32(10): 1593-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18321571

RESUMO

Approximately half of essential thrombocythemia (ET) patients and almost all with polycythemia vera (PV) bear the activating JAK2617V>F point mutation, which arises at the multipotent haemopoietic progenitor cell level. Although ET is mainly characterized by megacaryocyte proliferation, the cases that are positive for the JAK2617V>F mutation also show increased bone marrow cellularity and higher erythrocyte and granulocyte counts. After establishing short- and long-term bone marrow cultures we found that the frequency of committed haemopoietic progenitors in the bone marrow, was not increased in JAK2617V>F positive ET compared to the negative ones, whereas in long-term cultures (LTBMC) JAK2617V>F positive ET display a growth pattern more similar to that observed in LTBMC produced by PV marrow cells. Our data support the notion that JAK2617V>F positive ET and PV represents a continuum spectrum of alterations within the same disease.


Assuntos
Hematopoese/genética , Janus Quinase 2/genética , Mutação Puntual , Trombocitemia Essencial/genética , Substituição de Aminoácidos , Células Cultivadas , Células-Tronco Hematopoéticas/patologia , Humanos , Policitemia Vera/patologia , Trombocitemia Essencial/patologia
8.
Ann Hematol ; 84(3): 188-91, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15042315

RESUMO

Lymph node infiltration by monoclonal plasma cells can occur either in aggressive forms of myeloma or may represent regional extension of extramedullary plasmacytomas, whereas lymph node plasmacytoma presenting as a solitary extramedullary plasmacytoma is very unusual. We report two cases of lymph node plasmacytomas without systemic disease diagnosed after surgical excision. Clinical remission was achieved after local radiotherapy although one patient relapsed with multifocal extramedullary plasmacytomas 20 months after radiotherapy.


Assuntos
Plasmocitoma/patologia , Neoplasias Abdominais/patologia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Plasmócitos/patologia , Plasmocitoma/diagnóstico , Plasmocitoma/terapia , Neoplasias Retroperitoneais/patologia , Tomografia Computadorizada por Raios X
9.
Pancreatology ; 4(1): 22-7, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14988655

RESUMO

BACKGROUND/AIMS: Acute pancreatitis constitutes a systemic inflammatory process which is often accompanied by thrombosis and bleeding disorders. The role of platelets in the pathophysiology of the disease has not been elucidated yet. The present study focuses on two successive end-points: (1) the activation of platelets during acute pancreatitis and (2) the alterations of platelet number and indexes between onset and remission of the disease, which reflect the bone marrow response. METHODS: A cohort of 54 patients with acute pancreatitis was enrolled. Cause and severity of the disease (APACHE II score) were estimated. Activated platelet ratio (APR) was estimated using flow cytometry at onset and remission. Platelet number (PLT), mean platelet volume (MPV), platelet large cell ratio (P-LCR) and platelet distribution width (PDW) were collected at onset and remission. RESULTS: The first end-point was reached in patient 14 as APR was found elevated at onset of acute pancreatitis (p = 0.01). The second end-point was fulfilled in patient 12 for MPV, P-LCR and PDW, which were found elevated at remission of the disease (p < 0.01) but not for PLT until the last patient (p = 0.34). CONCLUSION: Platelets are directly involved in the systemic inflammatory process of acute pancreatitis, which leads to consumption, compensated by an immediate bone marrow response.


Assuntos
Plaquetas/fisiologia , Pancreatite/sangue , Contagem de Plaquetas , APACHE , Doença Aguda , Adulto , Idoso , Plaquetas/citologia , Células da Medula Óssea/fisiologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/etiologia , Pancreatite/fisiopatologia , Ativação Plaquetária , Análise de Regressão , Remissão Espontânea
10.
J Eur Acad Dermatol Venereol ; 17(1): 80-2, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12602979

RESUMO

Advanced stage mycosis fungoides (MF) generally has a poor prognosis, and currently there is no standard treatment available. Here we report the case of a young woman with recalcitrant tumour-stage MF (T3, stage IIb) whose disease was unresponsive to several therapeutic modalities, but who has showed sustained clinical response to pegylated liposomal doxorubucin. No severe infectious complications have been observed. The use of this drug in tumour-stage MF should be investigated further.


Assuntos
Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Micose Fungoide/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Feminino , Humanos , Lipossomos , Indução de Remissão
12.
Br J Haematol ; 102(5): 1241-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9753052

RESUMO

Bruton's tyrosine kinase (Btk) is a non-receptor protein tyrosine kinase (PTK) that is expressed in all haemopoietic lineages except mature T cells and plasma cells. Despite the broad range of expression. mutations that inactivate this molecule affect primarily the development of the B-cell lineage. As a PTK, Btk could potentially be involved directly or indirectly in the processes that relate to the malignant transformation of all the cell lineages where this molecule is expressed. Previous studies have failed to demonstrate mutations in patients with B-cell origin acute lymphoblastic leukaemia (ALL). We have utilized a recently developed method that enables the rapid and convenient detection of mutations at the cDNA level, namely, the non-isotopic RNase cleavage assay (NIRCA) to analyse Btk sequences from 27 patients with different types of acute myeloid leukaemia (AML). The only alteration that we observed was a polymorphism at position 2031. This polymorphism has already been seen in previous studies. Furthermore, using the same methodology, we identified the Btk mutations in six XLA (X-linked agammaglobulinaemia) patients. Our results, although they do not exclude the involvement of Btk mutations in the development or progression of some type of AML, nevertheless suggest that such mutations do not constitute a major co-factor in the development of myeloid malignancies.


Assuntos
Leucemia Mieloide/genética , Mutação , Proteínas Tirosina Quinases/genética , Doença Aguda , Adolescente , Adulto , Tirosina Quinase da Agamaglobulinemia , Idoso , Criança , DNA Complementar/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo
13.
Haematologica ; 82(2): 184-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9175324

RESUMO

Mild lymphocytosis (< 10 x 10(9)/L) is a common finding in routine blood tests. When it persists, it raises the question of whether this disorder is an early manifestation of chronic lymphocytic leukemia (CLL). If it is accompanied by bone marrow infiltration, it can be safely considered as a sign of CLL. The aim of this study was to analyze retrospectively the usefulness of immunophenotyping and immunogenotyping for early detection of lymphocyte clonality in ambiguous cases of lymphocytosis without bone marrow infiltration. Twenty-six healthy individuals, 47 to 77 years old, with an absolute lymphocyte count (ALC) at the "onset" of the disorder between 4 x 10(9)/L and 9 x 10(9)/L, without marrow infiltration, were studied and followed for a period of 31 to 51 months. CD19, CD20, CD5, CD2, CD4, CD8 surface markers and amplification of the Ig heavy chain CDR-3 locus were used for immunophenotypic and genotypic analysis, respectively. Our studies indicate that immunophenotyping alone is sufficient and superior to CDR-3 locus amplification for the early detection of lymphocyte clonality in peripheral blood. Furthermore, the high frequency of CLL development in individuals with established monoclonality strongly suggests that patients with mild borderline lymphocytosis, even without bone marrow infiltration, have to be followed for progression to CLL and its possible complications.


Assuntos
Leucemia Linfocítica Crônica de Células B/sangue , Linfocitose/patologia , Idoso , Humanos , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/patologia , Linfocitose/imunologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos
14.
Haematologica ; 81(4): 346-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8870381

RESUMO

Several groups have used high doses of interleukin-2 (IL-2), achieving a significant rate of responses in patients with acute myelogenous leukemia (AML). These results have mainly been observed in AML patients with limited disease (bone marrow blasts < 25%), but this therapy is associated with significant toxicity which is dose-related. In this report we describe a patient with AML in whom conventional chemotherapy had achieved partial remission. This patient received subcutaneously intermediate doses of IL-2 (12 x 10(6)/m2/week) and achieved complete remission which was maintained for eleven months. The side effects of IL-2 were mild. The results of this report document the antileukemic effect of IL-2 in AML with limited disease as well as the efficacy of subcutaneous maintenance treatment for prolonged periods.


Assuntos
Interleucina-2/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem
15.
Scand J Haematol ; 29(5): 398-404, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6218605

RESUMO

Cells from 13 cases of T-prolymphocytic leukaemia (T-PLL) were studied with a battery of immunological techniques in order to define their membrane phenotype. All cases were E-rosette positive and were negative with OKT6, anti-HLA-DR, anti-Ig and M-rosettes; in 3, 20-30% of the cells had receptors for C3b. 7 cases had predominantly a 'helper/inducer' T-subset phenotype, (OKT4+, OKT8-) and 4 had a 'suppressor/cytotoxic' phenotype (OKT8+, OKT4-). Cells in 2 cases coexpressed OKT4 and OKT8 in 48% and 95% of prolymphocytes and in another, both OKT4 and OKT8 were negative. Terminal transferase (TdT) was negative by IF in all the cases, but a low positive level was detected biochemically in one. Although T-PLL appears to be heterogenous in respect of membrane phenotype, the observation of unexpected features in 8 of the cases raises the possibility that it may originate in a cell of intermediate maturation between late thymocytes and mature T-lymphocytes. These features plus the clinical manifestation of the disease - typical morphology, splenomegaly, lymphadenopathy, skin lesions, high WBC and aggressive clinical course - help define T-PLL as a distinct clinicopathological entity.


Assuntos
Leucemia Linfoide/imunologia , Receptores de Antígenos de Linfócitos T/análise , Idoso , Anticorpos Monoclonais/imunologia , Feminino , Antígenos de Histocompatibilidade Classe II/análise , Humanos , Leucemia Linfoide/diagnóstico , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores de Antígenos de Linfócitos B/análise , Formação de Roseta , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia
16.
Lancet ; 1(8273): 639-43, 1982 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-6121963

RESUMO

Six Black patients (five born in the West Indies and one in Guyana), aged 21-55 years, had adult T-cell lymphoma-leukaemia diagnosed in the U.K. This disorder is rare in Europe and the U.S.A., but is more common in Japan. Five patients had severe hypercalcaemia which correlated with disease activity, although osteolytic lesions were found in only one. Other clinical features were lymphadenopathy and a high white blood-cell count (range 27-67 X 10(9)/l) with a predominance of pleomorphic lymphoid cells with pronounced nuclear irregularities prominent at ultrastructural level. The cells in all cases formed rosettes with sheep red blood-cells and lacked terminal transferase. Analysis with OKT monoclonal antibodies in four cases confirmed a mature T-cell phenotype defined as helper/inducer (T4+, T6-, T8-) in three. Combination chemotherapy resulted in short-lived remissions; four patients died and two have survived 3-6 months. The disease in these patients is indistinguishable on clinical and pathological grounds from adult T-cell leukaemia/lymphoma in Japan. Geographical clustering among certain racial groups suggests common aetiological factors in the pathogenesis of this disease. The finding of high titre antibody against the structural core protein (p24) of a new human C-type leukaemia virus (human T-cell leukaemia/lymphoma virus) in all tested cases from this series and data from all but one case from Japan suggest that one such factor may be viral.


Assuntos
Leucemia/epidemiologia , Linfoma/epidemiologia , Linfócitos T , Adulto , Fatores Etários , População Negra , Membrana Celular/patologia , Feminino , Humanos , Hipercalcemia/diagnóstico , Leucemia/diagnóstico , Contagem de Leucócitos , Linfoma/diagnóstico , Linfoma não Hodgkin/diagnóstico , Masculino , Pessoa de Meia-Idade , Linfócitos T/patologia , Reino Unido , Índias Ocidentais/etnologia
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