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1.
J Mol Cell Cardiol ; 101: 106-115, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27838371

RESUMO

AIMS: In atrial fibrillation, increased function of the Na+/Ca2+-exchanger (NCX) is one among several electrical remodeling mechanisms. METHODS/RESULTS: Using the patch-clamp- and Ca2+ imaging-methods, we investigated atrial myocytes from NCX-homozygous-overexpressor (OE)- and heterozygous-knockout (KO)-mice and their corresponding wildtypes (WTOE; WTKO). NCX mediated Ca2+ extrusion capacity was reduced in KO and increased in OE. There was no evidence for structural or molecular remodeling. During a proarrhythmic pacing-protocol, the number of low amplitude delayed afterdepolarizations (DADs) was unaltered in OE vs. WTOE and KO vs. WTKO. However, DADs triggered full spontaneous action potentials (sAP) significantly more often in OE vs. WTOE (ratio sAP/DAD: OE:0.18±0.05; WTOE:0.02±0.02; p<0.001). Using the same protocol, a DAD triggered an sAP by tendency less often in KO vs. WTKO (p=0.06) and significantly less often under a more aggressive proarrhythmic protocol (ratio sAP/DAD: KO:0.01±0.003; WT KO: 0.12±0.05; p=0.007). The DAD amplitude was increased in OE vs. WTOE and decreased in KO vs. WTKO. There were no differences in SR-Ca2+-load, the number of spontaneous Ca2+-release-events or IKACh/IK1. CONCLUSIONS: Atrial myocytes with increased NCX expression exhibited increased vulnerability towards sAPs while atriomyocytes with reduced NCX expression were protected. The underlying mechanism consists of a modification of the DAD-amplitude by the level of NCX-activity. Thus, although the number of spontaneous Ca2+-releases and therefore DADs is unaltered, the higher DAD-amplitude in OE made a transgression of the voltage-threshold of an sAP more likely. These findings indicate that the level of NCX activity could influence triggered activity in atrial myocytes independent of possible remodeling processes.


Assuntos
Átrios do Coração/metabolismo , Miócitos Cardíacos/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Potenciais de Ação/genética , Animais , Cálcio/metabolismo , Sinalização do Cálcio , Feminino , Expressão Gênica , Masculino , Potenciais da Membrana/genética , Camundongos , Camundongos Transgênicos , Contração Miocárdica/genética , Miocárdio/metabolismo , Retículo Sarcoplasmático/metabolismo , Trocador de Sódio e Cálcio/genética
2.
Ann Oncol ; 27(12): 2149-2160, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27701070

RESUMO

The European Society for Medical Oncology (ESMO) consensus conference on mature B-cell lymphomas and chronic lymphocytic leukaemia (CLL) was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (i) the elderly patient, (ii) prognostic factors suitable for clinical use and (iii) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address four clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the four questions assigned to their group. These recommendations were then presented to the entire panel and a consensus was reached. This manuscript presents recommendations dedicated to the second area of interest, i.e. prognostic factors suitable for clinical use. The four topics [i.e. interim positron emission tomography (PET), TP53 mutations, cell of origin (COO) and minimal residual disease (MRD)] were primarily chosen because of the bulk of available data together with the lack of clear guidance regarding their use in clinical practice and within clinical trials. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. The panel acknowledged that detection of TP53 inactivation by deletion or mutation in CLL should be implemented in clinical practice (level of evidence I, strength of recommendation A). Due to their potentially high prognostic value, at least in some lymphoma entities, implementation of interim PET, COO and MRD was highly recommended in the context of clinical trials. All expert panel members approved this final article.


Assuntos
Leucemia Linfocítica Crônica de Células B/patologia , Linfoma de Células B/patologia , Linfoma/patologia , Oncologia , Idoso , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Linfoma/epidemiologia , Linfoma de Células B/epidemiologia , Prognóstico , Fatores de Risco , Sociedades Médicas , Suíça
3.
Europace ; 18(1): 78-84, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25883082

RESUMO

BACKGROUND: Silent cerebral lesions with the multielectrode-phased radiofrequency (RF) pulmonary vein ablation catheter (PVAC(®)) have recently been investigated. However, comparative data on safety in relation to irrigated RF ablation are missing. METHODS AND RESULTS: One hundred and fifty consecutive patients (58 ± 12 years, 56 female) underwent first pulmonary vein isolation (PVI) for atrial fibrillation (61% paroxysmal) using PVAC(®) (PVAC). Procedure data as well as in-hospital complications were compared with 300 matched patients who underwent PVI using irrigated RF (iRF). Procedure duration (148 ± 63 vs. 208 ± 70 min; P < 0.001), RF duration (24 ± 10 vs. 49 ± 25 min; P < 0.001), and fluoroscopy time (21 ± 10 vs. 35 ± 13 min; P < 0.001) were significantly shorter using PVAC. Major complication rates [major bleeding, transitoric ischaemic attack (TIA), and pericardial tamponade] were not significantly different between groups (PVAC, n = 3; 2% vs. iRF n = 17; 6%). Overall complication rate, including minor events, was similar in both groups [n = 21 (14%) vs. n = 48 (16%)]. Most of these were bleeding complications due to vascular access [n = 8 (5.3%) vs. n = 22 (7.3%)], which required surgical intervention in five patients [n = 1 (0.7%) vs. n = 4 (1.3%)]. Pericardial effusion [n = 4 (2.7%) vs. n = 19 (6.3%); pericardial tamponade requiring drainage n = 0 vs. n = 6] occurred more frequently using iRF. Two patients in each group developed a TIA (1.3% vs. 0.6%). Of note, four of five thromboembolic events in the PVAC group (two TIAs and three transient ST elevations during ablation) occurred when all 10 electrodes were used for ablation. CONCLUSION: Pulmonary vein isolation using PVAC as a 'one-shot-system' has a comparable complication rate but a different risk profile. Pericardial effusion and tamponade occurred more frequently using iRF, whereas thromboembolic events were more prevalent using PVAC. Occurrence of clinically relevant thromboembolic events might be reduced by avoidance of electrode 1 and 10 interaction and uninterrupted anticoagulation, whereas contact force sensing for iRF might minimize pericardial effusion.


Assuntos
Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/instrumentação , Complicações Pós-Operatórias/epidemiologia , Veias Pulmonares/cirurgia , Irrigação Terapêutica/instrumentação , Ablação por Cateter/estatística & dados numéricos , Comorbidade , Eletrodos , Desenho de Equipamento , Falha de Equipamento , Análise de Falha de Equipamento , Feminino , Sistema de Condução Cardíaco/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Irrigação Terapêutica/estatística & dados numéricos , Resultado do Tratamento
4.
Ann Oncol ; 24(6): 1609-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23393125

RESUMO

BACKGROUND: Long-term clinical and molecular remissions in patients with follicular lymphoma (FL) following high-dose therapy (HDT) and autologous stem cell transplantation (ASCT) have been evaluated in only a few studies. Results are especially limited for second-line HDT with BEAM (BCNU, etoposide, cytarabine and melphalan). PATIENTS AND METHODS: Sixty patients with FL received ASCT in our institution (18 first-line with total body irradiation and cyclophosphamide, 34 second-line with BEAM and 8 ≥ third-line with BEAM). In the case of long-term remission (>6 years; N = 17), peripheral blood was tested for minimal residual disease by t(14;18)- and IGH-PCR. RESULTS: Ten-year overall survival, progression-free survival and freedom from progression (FFP) after first-line ASCT were 79%, 57% and 64% after second-line ASCT 41%, 35% and 42%, respectively. Prognostic factors for FFP were treatment line and FLIPI (Follicular Lymphoma International Prognostic Index). Ten-year FFP for second-line ASCT and low-risk FLIPI was 57%, intermediate risk 37% and high risk 33%. No relapses occurred after 6 years following ASCT. Sixteen patients developed sustained long-term clinical and molecular remissions of up to 17.5 years. CONCLUSION: Sustained long-term clinical and molecular remissions can be achieved following ASCT, including HDT with BEAM in second line.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/cirurgia , Transplante de Células-Tronco/métodos , Adulto , Idoso , Carmustina/administração & dosagem , Estudos de Coortes , Terapia Combinada/métodos , Terapia Combinada/mortalidade , Citarabina/administração & dosagem , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfoma Folicular/mortalidade , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Podofilotoxina/administração & dosagem , Indução de Remissão/métodos , Transplante de Células-Tronco/mortalidade , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento
6.
Ann Hematol ; 91(11): 1765-72, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22926531

RESUMO

In most patients, mantle cell lymphoma (MCL) shows an aggressive clinical course with a continuous relapse pattern and a median survival of only 3-5 years. In the current study generation of the European MCL Network, the addition of high-dose Ara-C to R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone)-like regimen followed by myeloablative consolidation achieved a significant improvement of progression-free survival in younger patients. In elderly patients, rituximab maintenance led to a marked prolongation of remission duration. Emerging strategies include mammalian target of rapamycin (mTOR) inhibitors, proteasome inhibitors, immune modulatory drugs, Bruton's tyrosine kinase inhibitors and others, all based on the dysregulated control of cell cycle machinery and impairment of several apoptotic pathways. Combination strategies are currently being investigated in numerous trials, but their introduction into clinical practice and current treatment algorithms remains a challenge. In the current survey, the application of the molecular targeted compounds were collected and evaluated by a representative national network of 14 haematological institutions. Optimised strategies are recommended for clinical routine. Future studies will apply individualised approaches according to the molecular risk profile of the patient.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medicina Baseada em Evidências , Linfoma de Célula do Manto/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Criança , Conferências de Consenso como Assunto , Quimioterapia de Consolidação/efeitos adversos , Quimioterapia de Consolidação/métodos , União Europeia , Pesquisas sobre Atenção à Saúde , Humanos , Quimioterapia de Indução/efeitos adversos , Quimioterapia de Indução/métodos , Linfoma de Célula do Manto/prevenção & controle , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Análise de Sobrevida
7.
Braz J Biol ; 84: e256916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35043839

RESUMO

Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Assuntos
Artrópodes , Crotalaria , Fabaceae , Alcaloides de Pirrolizidina , Animais , Monocrotalina/toxicidade
8.
Sci Rep ; 11(1): 4728, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33633186

RESUMO

Pulmonary vein isolation (PVI) using cryoenergy is safe and efficient for treatment of atrial fibrillation (AF). Pre-existing upper gastrointestinal (GI) pathologies have been shown to increase the risk for AF. Therefore, this study aimed at assessing incidental pathologies of the upper GI tract in patients scheduled for PVI and to analyse the impact of patients' characteristics on PVI safety outcome. In 71 AF patients, who participated in the MADE-PVI trial, oesophagogastroduodenoscopy and endosonography were prospectively performed directly before and the day after PVI to assess pre-existing upper GI pathologies and post-interventional occurrence of PVI-associated lesions. Subgroup analysis of the MADE-PVI trial identified clinically relevant incidental findings in 53 patients (74.6%) with age > 50 years being a significant risk factor. Pre-existing reflux oesophagitis increased risk for PVI-associated mediastinal oedema, while patients already treated with proton pump inhibitors (PPI) had significantly fewer mediastinal oedema. Our results suggest that AF patients with pre-existing reflux oesophagitis are at higher risk for PVI-associated mediastinal lesions, which is decreased in patients with constant PPI-treatment prior to PVI. Since PVI-associated mediastinal lesions are regarded as surrogate parameter for an increased risk of the fatal complication of an oesophago-atrial fistula, our findings hint at a beneficial effect of pre-interventional prophylactic PPI-treatment to reduce risk for PVI-associated complications.German Clinical Trials Register (DRKS00016006; date of registration: 17/12/2018).


Assuntos
Criocirurgia/métodos , Inibidores da Bomba de Prótons/uso terapêutico , Veias Pulmonares/cirurgia , Idoso , Fibrilação Atrial/cirurgia , Criocirurgia/efeitos adversos , Feminino , Refluxo Gastroesofágico/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
9.
Ann Oncol ; 20(4): 722-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19179546

RESUMO

BACKGROUND: Pattern and outcome of disease recurrence after autologous stem-cell transplantation (autoSCT) for follicular lymphoma (FL) is not well known. PATIENTS AND METHODS: Relapse cases were identified from 241 consecutive patients autografted for disseminated untransformed FL from 1990 to 2002 in three institutions. Prognostic factors for relapse and outcome after relapse were analyzed by log-rank comparisons and Cox regression analyses. RESULTS: One hundred and three relapses occurred. The 10-year relapse probability was 47%. Median time from autoSCT to relapse was 20 (2-128) months. Only three relapses were observed later than 6 years posttransplant. Median survival after relapse was 8.3 years. Patients with disease recurrence within 1 year from transplant and those who had received autoSCT as second-line treatment had significantly reduced survival by multivariate analysis, whereas Follicular Lymphoma International Prognostic Index score, age, remission status at autoSCT, high-dose regimen, and ex vivo purging had no impact. CONCLUSIONS: FL recurrence after autoSCT follows a biphasic pattern with continuing relapse during the first 6 years and only few events thereafter. The prognosis after relapse is relatively good and appears to be comparable to that of disease recurrence after standard treatment. The situation is less favorable for patients who relapse within the first posttransplant year.


Assuntos
Linfoma Folicular/cirurgia , Transplante de Células-Tronco , Seguimentos , Humanos , Linfoma Folicular/patologia , Recidiva , Condicionamento Pré-Transplante , Transplante Autólogo
10.
Braz. j. biol ; 84: e256916, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355874

RESUMO

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.


Assuntos
Animais , Artrópodes , Alcaloides de Pirrolizidina , Crotalaria , Fabaceae , Monocrotalina/toxicidade
11.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469325

RESUMO

Abstract Crotalaria (Fabaceae) occurs abundantly in tropical and subtropical regions and has about 600 known species. These plants are widely used in agriculture, mainly as cover plants and green manures, in addition to their use in the management of phytonematodes. A striking feature of these species is the production of pyrrolizidine alkaloids (PAs), secondary allelochemicals involved in plant defense against herbivores. In Crotalaria species, monocrotaline is the predominant PA, which has many biological activities reported, including cytotoxicity, tumorigenicity, hepatotoxicity and neurotoxicity, with a wide range of ecological interactions. Thus, studies have sought to elucidate the effects of this compound to promote an increase in flora and fauna (mainly insects and nematodes) associated with agroecosystems, favoring the natural biological control. This review summarizes information about the monocrotaline, showing such effects in these environments, both above and below ground, and their potential use in pest management programs.


Resumo Crotalaria (Linnaeus, 1753) (Fabaceae) ocorre abundantemente em regiões tropicais e subtropicais e tem cerca de 600 espécies conhecidas. Estas plantas são amplamente utilizadas na agricultura, principalmente como cobertura e adubos verdes, além da sua utilização no manejo de fitonematoides. Uma característica marcante destas espécies é a produção de alcalóides pirrolizidinicos (APs), aleloquímicos secundários envolvidos na defesa das plantas contra os herbívoros. Nas espécies de Crotalaria, a monocrotalina é a AP predominante, que tem muitas atividades biológicas relatadas, incluindo citotoxicidade, tumorigenicidade, hepatotoxicidade e neurotoxicidade, além de uma vasta gama de interações ecológicas. Assim, estudos têm procurado elucidar os efeitos desse composto para promover um incremento na flora e fauna (principalmente insetos e nematoides) associados aos agroecossistemas, favorecendo o controle biológico natural. Esta revisão compila informações sobre a monocrotalina, mostrando tais efeitos nesses ambientes, tanto acima como abaixo do solo e a sua potencial utilização em programas de manejo de pragas.

12.
Oncogene ; 26(19): 2685-94, 2007 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-17072339

RESUMO

The human c-rel proto-oncogene (REL) encodes a subunit of the nuclear factor-kappaB (NF-kappaB) transcription factor. In this report, we have identified an identical point mutation in two human B-cell lymphomas (follicular (FL) and mediastinal) that changes serine (Ser)525 (TCA) to proline (Pro) (CCA) within the REL transactivation domain. This mutation was not identified in a similarly sized cohort of healthy individuals. In the mediastinal B-cell lymphoma, the mutation in REL is of germ-line origin. In both tumors, the S525P mutant allele is over-represented. REL-S525P shows enhanced in vitro transforming activity in chicken spleen cells. REL-S525P has a reduced ability to activate the human manganese superoxide dismutase (MnSOD) promoter in A293 cells; however, the MnSOD protein shows increased expression in REL-S525P-transformed chicken spleen cells as compared to wild-type REL-transformed cells. Ser525 is a site for phosphorylation by IkappaB kinase (IKK) in vitro. The S525P mutation reduces IKKalpha- and tumor necrosis factor (TNF)alpha-stimulated transactivation by a GAL4-REL protein. Furthermore, REL-S525P-transformed chicken spleen cells are more resistant to TNFalpha-induced cell death than cells transformed by wild-type REL. These results suggest that the S525P mutation contributes to the development of human B-cell lymphomas by affecting an IKKalpha-regulated transactivation activity of REL.


Assuntos
Transformação Celular Viral , Quinase I-kappa B/fisiologia , Linfoma de Células B/genética , Mutação Puntual/genética , Proteínas Proto-Oncogênicas c-rel/genética , Sequência de Aminoácidos , Animais , Western Blotting , Galinhas , Ensaio de Desvio de Mobilidade Eletroforética , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Hibridização in Situ Fluorescente , Rim/metabolismo , Luciferases/metabolismo , Linfoma de Células B/metabolismo , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Neoplasias do Mediastino/genética , Neoplasias do Mediastino/metabolismo , Dados de Sequência Molecular , NF-kappa B/genética , NF-kappa B/metabolismo , Fosforilação , Regiões Promotoras Genéticas/genética , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-rel/metabolismo , Homologia de Sequência de Aminoácidos , Baço/metabolismo , Baço/virologia , Ativação Transcricional , Fator de Necrose Tumoral alfa/farmacologia
13.
Pharmazie ; 61(4): 255-60, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16649533

RESUMO

Next to beta1- and beta2-adrenoceptors, a third beta-adrenoceptor population is expressed in the human heart, the beta3-adrenoceptor. In mammalian ventricular myocytes, beta3-adrenergic stimulation leads to a decrease in contractility via a release of nitric oxide (NO). Recently, different molecular mechanisms of beta3-adrenergic activation of endothelial nitric oxide synthase (eNOS) have been uncovered in cardiac myocytes. In the non-failing and especially the failing heart, beta3-adrenergic stimulation may offer protection against excessive catecholaminergic beta1-adrenoceptor stimulation. In this context, the beta3-adrenoceptor is discussed as a novel target for the pharmacological therapy of heart failure.


Assuntos
Agonistas de Receptores Adrenérgicos beta 3 , Agonistas Adrenérgicos beta/uso terapêutico , Cardiopatias/tratamento farmacológico , Coração/efeitos dos fármacos , Transdução de Sinais/fisiologia , Humanos , Estimulação Química
14.
Cancer Res ; 51(12): 3243-50, 1991 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2039999

RESUMO

We have examined 165 unselected cases of non-Hodgkin's lymphomas for rearrangements involving the t(14;18) major breakpoint region using a polymerase chain reaction (PCR) and direct sequencing of amplified major breakpoint region bcl-2/JH junctional regions. The lymphomas, diagnosed according to the updated Kiel classification, consisted of 33 centroblastic-centrocytic, 37 centroblastic, 27 immunocytic, 10 immunoblastic, 10 centrocytic, 2 lymphoblastic, 2 Ki-1-positive anaplastic large cell, 14 peripheral T-cell, and 4 unclassified lymphomas. In addition 18 chronic lymphocytic leukemias, 2 hairy cell leukemias, and 6 plasmacytomas were studied. In 17 cases a bcl-2/JH gene fusion sequence was amplified by PCR. A bcl-2/JH gene fusion was detected only in three lymphoma subgroups: 13 of 33 centroblastic-centrocytic (39%), 2 of 37 centroblastic (6%), and 2 of 27 immunocytic (8%) were positive. In two cases, major breakpoint region bcl-2 rearrangements verified by genomic Southern analysis were not detected by PCR. Direct sequencing of all 17 PCR-amplified, previously uncharacterized t(14;18) junctional regions provided corroborating evidence for the specificity of the assay. The procedure gave sequencing results even from limited amounts of lymphoma cells as obtained by fine needle aspiration of lymph nodes or from clinically uninvolved sites. Clone-specific sequences were identified due to the involvement of different JH segments, the variations among the exact JH and bcl-2 breakpoint positions, and the extensive incorporation of junctional region (D-) N-nucleotides. These clone-specific sequences allow accurate identification of clinically occult lymphoma cells and reduce the threat of false positive results. The finding of exceptionally long intervening sequences in some of the junctions and the partial homology with published DH segments in three cases support the view that some of the putative N-regions harbor DH regions.


Assuntos
Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , DNA de Neoplasias/genética , Linfoma não Hodgkin/genética , Translocação Genética , Antígenos CD/análise , Sequência de Bases , Medula Óssea/patologia , Clonagem Molecular , Frequência do Gene , Humanos , Íntrons , Linfonodos/patologia , Linfoma não Hodgkin/classificação , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/patologia , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Reação em Cadeia da Polimerase
15.
Cancer Res ; 61(4): 1629-36, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11245476

RESUMO

The t(11;14)(q13;q32) between the BCL-1 and immunoglobulin heavy chain gene (IgH) loci in mantle cell lymphoma (MCL) are believed to be mediated by the mechanism of V(D)J recombination similar to the t(14; 18) in follicular lymphoma (FL). We have recently shown that the t(14;18) event creates staggered double-strand breaks in the BCL-2 locus, and that the t(14;18) junctions contain templated nucleotide insertions (T-nucleotides; U. Jäger et al., Blood, 95: 3520-3529, 2000). Reasoning that the earlier (pregerminal center) B-cell origin of MCL might be reflected in a different molecular structure of the chromosomal breakpoints, we PCR-amplified diagnostic samples from 93 patients. Thirty-six samples (39%) were positive for the direct (BCL-1/J(H)) and 23 for both direct and reciprocal (D(H)/BCL-1) junctions. The breaks on chromosome 14 exhibited features of V(D)J-mediated recombination as shown by D(H) and J(H) coding end processing. However, duplications of BCL-1 sequences in 39% of the 23 patients indicate staggered double-strand breaks in the major translocation cluster region (MTC). This is incompatible with V(D)J recombination and indicates a different mechanism of cleavage. The use of J(H)6 in the junctions (39%) was similar to that in the immunoglobulin genes of normal B cells and B-CLL, but considerably less than in FL. Only 2 of 36 samples contained a BCL-1/DJ(H) rearrangement, which was indicative of a previous DJ(H) rearrangement. Most importantly, 19% of the BCL-1/IgH junctions with inserts of > or =5 nucleotides contained error-prone copies (T-nucleotides) of 8-12 nucleotides originating from the surrounding BCL-1 or IgH regions, a lower rate than in FL. No correlation was found between the addition of T-nucleotides and the rate of somatic mutation in the immunoglobulin genes. We conclude that the t(11;14) and t(14;18) use the same basic mechanism of translocation including V(D)J-mediated recombination, double-strand staggered breaks, and template-dependent, error-prone DNA-synthesis. However, the distinct differences in the utilization of J(H) regions suggest that the t(11;14) occurs predominantly during an attempted primary D(H)-J(H) rearrangement in early B cells, whereas the t(14;18) mostly occurs during secondary rearrangement. This is in agreement with the pregerminal center B-cell origin of MCL.


Assuntos
Genes de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias J de Imunoglobulina/genética , Linfoma de Célula do Manto/genética , Translocação Genética/genética , Sequência de Bases , Quebra Cromossômica/genética , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Elementos de DNA Transponíveis/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B/genética , Genes bcl-1/genética , Humanos , Idiótipos de Imunoglobulinas/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Moldes Genéticos
16.
J Clin Oncol ; 19(18): 3861-73, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11559724

RESUMO

PURPOSE: The study was initiated to obtain epidemiologic data and information on anatomic and histologic distribution, clinical features, and treatment results in patients with primary gastrointestinal non-Hodgkin's lymphomas (PGI NHL). PATIENTS AND METHODS: Between October 1992 and November 1996, 371 PGI NHL patients were eligible to evaluate clinical features. Radiotherapy and chemotherapy were stratified according to histologic grading, stage, and whether surgery had been carried out or not. RESULTS: A total of 74.8% patients had gastric NHL (PGL). Within the intestine, the small bowel and the ileocecal region were involved in 8.6% and 7.0% of the cases, respectively. Multiple GI involvement (MGI) was 6.5%. Approximately 90% of the GI NHL were in stages IE/IIE. Aggressive NHL accounted for the majority, with a distinguishable pattern in several sites. Forty percent of PGL were of low-grade mucosa-associated lymphatic tissue type. One third of large-cell lymphomas had low-grade components. Most intestinal NHL were germinal-center lymphomas. The site of origin was prognostic. In gastric and ileocecal lymphoma, event-free (EFS) and overall survival (OS) were significantly higher as compared with the small intestine or MGI (median time of observation, 51 months). In PGL, localized disease was prognostic for EFS and OS. Histologic grade influenced only EFS significantly. Numbers in intestinal lymphomas were too small for subanalyses. CONCLUSION: PGI NHL are heterogeneous diseases. The number of localized PGL allowed for detailed analyses. Larger studies are needed for stages III and IV and for intestinal NHL. A uniform reporting system for PGI NHL, in terms of definitions and histologic and staging classifications, is needed to facilitate comparison of treatment results.


Assuntos
Neoplasias Gastrointestinais/terapia , Linfoma não Hodgkin/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Gastrointestinais/patologia , Alemanha , Humanos , Linfoma não Hodgkin/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Sistema de Registros , Análise de Sobrevida
17.
J Clin Oncol ; 19(18): 3874-83, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11559725

RESUMO

PURPOSE: The aim of the study was to obtain data on anatomic and histologic distribution, clinical features, and treatment results of patients with primary gastrointestinal non-Hodgkin's lymphomas, particularly combined surgical and conservative treatment (CSCT) versus conservative treatment (CT) alone for primary gastric lymphoma (PGL) in localized stages. PATIENTS AND METHODS: Whether the treatment included surgery was left to the discretion of each participating center. Radiotherapy (Rx) and chemotherapy were stratified according to histologic grading, stage, and the inclusion or omission of surgery as follows: patients with low-grade PGL were treated with extended-field (EF) Rx (30 Gy). In case of residual tumor after surgery or in case of CT only (in stage IIE after six cycles of cyclophosphamide, vincristine, and prednisone), an additional boost of 10 Gy was given. All patients with high-grade PGL were treated with four (stage IE) or six (stage IIE) cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone followed by EF Rx (stage IE) or involved-field (IF) Rx (stage IIE). Rx dosage corresponded to low-grade NHL. RESULTS: Between October 1992 and November 1996, 106 patients had CT only. The survival rate (SR) after 5 years was 84.4% and was influenced neither by patients' characteristics nor by stage or histologic grade. Seventy-nine patients had CSCT. Their SR was 82.0%. Complete resection of the tumor (R0) was prognostic for the overall survival (P =.0165) as compared with incomplete resection. CONCLUSION: Although the study was not randomized, a stomach-conserving approach may be favored.


Assuntos
Neoplasias Gastrointestinais/terapia , Linfoma não Hodgkin/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/cirurgia , Humanos , Linfoma não Hodgkin/patologia , Linfoma não Hodgkin/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Qualidade de Vida , Análise de Sobrevida
18.
Leukemia ; 11 Suppl 2: S25-8, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9178834

RESUMO

The purine analogs fludarabine (FAMP) and 2-chlorodeoxyadenosine (2-CDA) are highly active in chronic lymphocytic leukemia (CLL). In second-line therapy response rates are in the range of 30 to 60% and exceed 70% when applied to previously untreated patients. While FAMP in particular is thus well established for salvage treatment and can be considered as the present treatment of choice, more data are needed to define the role of purine analogs for first-line therapy.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cladribina/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Vidarabina/análogos & derivados , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Cladribina/administração & dosagem , Cladribina/efeitos adversos , Ensaios Clínicos como Assunto , Humanos , Vidarabina/administração & dosagem , Vidarabina/efeitos adversos , Vidarabina/uso terapêutico
19.
Leukemia ; 9(12): 2133-7, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8609729

RESUMO

The development of rapid PCR protocols for amplification of rearranged IgH gene sequences has greatly facilitated the identification of clonal IGH rearrangements in non-Hodgkin's lymphomas (NHL) and leukemias. However, the 15-35% incidence of false negative results with this approach has been a constant and unresolved problem. To assess the reliability of a previously published framework region 3 (FR3A) IgH-CDR3-PCR for detection of monoclonal IgH gene rearrangements we compared the PCR and Southern results in a series of 44 NHL and leukemias of B cell lineage showing a JH-rearrangement in Southern analysis with genomic DNA and hybridization with a IgH joining region (JH) probe. IgH-CDR3 regions were amplified using DNA extracted from clinical specimens by PCR using fluorescent dye-labeled consensus primers homologous to conserved regions within the variable (VH) and the joining (JH) gene segments. The PCR products were size separated on a high resolution polyacrylamide gel and analyzed for clonality by exact size determination and fluorescence quantification in an automated DNA sequencer. With commonly used DNA polymerases monoclonal IgH-CDR3 junctions were identified in 36/44 samples (82%). However, in the remaining eight cases (18%) with pathohistologically clearly demonstrated B cell malignancies which were also monoclonal on JH-Southern analysis, monoclonality could be demonstrated by FR3A-IgH-CDR3-PCR only with the proofreading UITma DNA polymerase. In four of these monoclonal VH--N--DH--N--JH junctions sequence analysis was performed which showed a point mutation in one and a single nucleotide deletion at the 3' terminus of the primer target site in the other case. In the remaining two cases no primer mismatches could be identified. Thus we conclude that the marked improvement of the PCR-detection rate of monoclonal IgH-CDR3 junctions was achieved at least in part due to the ability of UITma DNA polymerase to remove mismatched bases at the 3' terminus of the primers with respect to the target during the first amplification cycles. Our results suggest, that UITma is the DNA polymerase of choice for amplification of IgH-CDR3 junctions with consensus FR3A-VH- and JH-primers.


Assuntos
Cadeias Pesadas de Imunoglobulinas/genética , Cadeias J de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/imunologia , Reação em Cadeia da Polimerase/métodos , Sequência de Bases , DNA Polimerase Dirigida por DNA , Rearranjo Gênico do Linfócito B , Humanos , Dados de Sequência Molecular
20.
Leukemia ; 14(8): 1419-25, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10942238

RESUMO

PCR of clonally rearranged immunoglobulin heavy chain (IgH) gene sequences is increasingly used for detection of minimal residual disease (MRD) in lymphoid malignancies. Inherent quantitating problems are the main drawbacks of traditional PCR technologies. These limitations have been overcome by the recently developed real-time quantitative PCR (RQ PCR) technology. However, clinical application of the few published RQ PCR assays targeting immune gene rearrangements is hampered by the expensive and time-consuming need for individual hybridization probes for each patient. We have developed a new RQ PCR strategy targeting clonally rearranged IgH sequences that solves this problem. The method uses only two different JH hybridization probes and four downstream JH primers homologous to consensus germline JH gene segments. In combination with an allele-specific upstream (ASO) primer the consensus JH probes and primers allow quantitation of about 90% of possible IgH rearrangements. In a series of 22 B-lineage ALL the new assay allowed the detection of one to 10 blasts in a background of 10(5) normal cells. To prove the clinical utility we quantified MRD in 23 follow-up samples of six ALL patients with the new assay in comparison with a published RQ PCR technique that used individually designed primer/probe sets. We showed that the sensitivity of the new RQ PCR assay was slightly higher for four of the six cases and about 100-fold higher for one case, enabling detection of an increasing MRD level as an indicator of subsequent relapse 44 weeks earlier compared to the ASO probe assay in this particular patient. The results suggest, that the novel RQ PCR assay is a rapid, technically simple, reliable, and sensitive alternative to traditional quantification assays and simplifies current approaches of monitoring MRD in clinical trials.


Assuntos
Linfoma de Burkitt/patologia , Sequência de Bases , Primers do DNA , Corantes Fluorescentes , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Neoplasia Residual , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
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