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1.
Gynecol Obstet Fertil Senol ; 50(7-8): 519-526, 2022.
Artigo em Francês | MEDLINE | ID: mdl-35595063

RESUMO

OBJECTIVE: Analyze the complication rate of pregnancy termination between 12 and 16 weeks of gestation, depending on the method and the exact term. MATERIAL AND METHODS: Retrospective study focuses on patients who were going through a pregnancy termination between January 2015 and December 2020 at the Necker Universitary hospital in Paris. Two methods were applied: surgical abortion or medical evacuation. We compared 4 groups of patients depending on methods and term (12-14 or 14-16 weeks of gestation). The main complications such as hemorrhage, infection, need for surgery were collected. RESULTS: 414 patients were included. Blood loss and hemorrhage rate>500cc were higher for surgical abortion (3.5 vs 55% P<0.001), but the medical evacuation lead to an important rate of secondary aspiration for trophoblastic retention (14.7% vs 1.5% P<0.001). We didn't observe any difference regarding the complication rate for medical evacuation depending on the term. However, in case of surgical abortion the increase of term from 12-14 to 14-16 weeks of gestation leads to a tiny increment of the transfusion rate (0.6% vs 4.4% P=0.04), even if the hemorrhage rate >500cc didn't significantly differ (50,3 vs 57,9% P=0,2). CONCLUSION: Surgical abortion between 12 and 16 weeks of gestation exposed the patients to an increased hemorrhagic risk, while the medical evacuation required more secondary aspiration for trophoblastic retention. The term of the abortion didn't affect the complication rate, beside a tiny increase in transfusion rate for surgical abortion.


Assuntos
Aborto Induzido , Aborto Espontâneo , Aborto Induzido/efeitos adversos , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Feminino , Hemorragia/etiologia , Humanos , Paris , Gravidez , Estudos Retrospectivos
2.
Leukemia ; 29(5): 999-1003, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25652737

RESUMO

Treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors has advanced to a stage where many patients achieve very low or undetectable levels of disease. Remarkably, some of these patients remain in sustained remission when treatment is withdrawn, suggesting that they may be at least operationally cured of their disease. Accurate definition of deep molecular responses (MRs) is therefore increasingly important for optimal patient management and comparison of independent data sets. We previously published proposals for broad standardized definitions of MR at different levels of sensitivity. Here we present detailed laboratory recommendations, developed as part of the European Treatment and Outcome Study for CML (EUTOS), to enable testing laboratories to score MR in a reproducible manner for CML patients expressing the most common BCR-ABL1 variants.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Calibragem , Europa (Continente) , Proteínas de Fusão bcr-abl/genética , Perfilação da Expressão Gênica , Variação Genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Limite de Detecção , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Resultado do Tratamento
3.
Leukemia ; 22(1): 96-102, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17943168

RESUMO

Individualized PCR strategies hamper comparability of molecular results between different laboratories in several fields of medicine. To harmonize BCR-ABL mRNA quantification an international multicenter trial involving 37 laboratories in 14 countries was initiated using 10 samples, each containing various dilutions (10, 2, 1 and 0.1%) of b3a2 or b2a2 BCR-ABL positive in normal leukocytes and negative controls. A novel control plasmid (pME-2) was designed for external calibration containing BCR-ABL and glucuronidase-beta (GUS) sequences. Median BCR-ABL/ABL ratios were 9.1, 1.8, 0.85 and 0.11% in b3a2 samples and 9.5, 1.6, 0.84 and 0.11% in b2a2 samples. Median BCR-ABL/GUS ratios were 3.4, 0.77, 0.37 and 0.042% in b3a2 samples and 2.8, 0.48, 0.29 and 0.031% in b2a2 samples. The coefficients of variation were 0.62 for ratios BCR-ABL/ABL and 1.03 for ratios BCR-ABL/GUS. Five of 37 evaluable participating laboratories (13%) detected low BCR-ABL copy numbers in negative control samples; one laboratory failed to detect BCR-ABL in a low-level sample. We conclude that the use of a common control plasmid does indeed improve comparability of BCR-ABL mRNA quantification results. However, further standardizing efforts like introducing a calibrator and regular control rounds are needed.


Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Plasmídeos , RNA Mensageiro/análise , Idoso , Feminino , Glucuronidase/genética , Glucuronidase/metabolismo , Humanos , Laboratórios , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Masculino , RNA Neoplásico/genética , Padrões de Referência , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas
4.
Leukemia ; 21(7): 1442-50, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17508006

RESUMO

Idiopathic hypereosinophilic syndromes (HES) comprise a spectrum of indolent to aggressive diseases characterized by persistent hypereosinophilia. Hypereosinophilia can result from the presence of a defect in the hematopoietic stem cell giving rise to eosinophilia, it can be present in many myeloproliferative disorders or alternatively it may be a reactive form, secondary to many clinical conditions. The hybrid gene FIP1L1-PDGRFalpha was identified in a subset of patients presenting with HES or chronic eosinophilic leukemia (CEL). In spite of this, the majority of HES patients do not present detectable molecular lesions and for many of them the diagnosis is based on exclusion criteria and sometimes it remains doubt. In this study we explored the possibility to distinguish between HES/CEL and reactive hypereosinophilia based on WT1 transcript amount. For this purpose, 312 patients with hypereosinophilia were characterized at the molecular and cytogenetic level and analyzed for WT1 expression at diagnosis and during follow-up. This study clearly demonstrates that WT1 quantitative assessment allows to discriminate between HES/CEL and reactive eosinophilia and represents a useful tool for disease monitoring especially in the patients lacking a marker of clonality.


Assuntos
Eosinofilia/diagnóstico , Síndrome Hipereosinofílica/diagnóstico , RNA Neoplásico/análise , Proteínas WT1/genética , Adulto , Idoso , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Proteínas WT1/análise
5.
Am J Hematol ; 81(12): 938-45, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16960866

RESUMO

NF-kB is a transcription factor that mediates antiapoptotic signals in several cancer cell lines. Here we have demonstrated that the cytotoxic drug, Etoposide, activates NF-kB in K562, a chronic myeloid leukemia blast crisis cell line. Treatment with the NF-kB inhibitors MG-132, Bay11-7082, and Resveratrol impedes Etoposide-induced NF-kB activation, rendering K562 sensitive to Etoposide-induced apoptosis. Stable expression of mutant form of IkB-alpha, which retains NF-kB inactive in the cytoplasm of cells, confirmed the data obtained with molecular inhibitors. Both inhibitors and stable expression of SR-IkB are associated with down-modulation of the antiapoptotic protein Bcl-xL, suggesting that the survival pathway activated by Etoposide involves NF-kB-mediated Bcl-xL expression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Etoposídeo/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Antineoplásicos Fitogênicos/agonistas , Antineoplásicos Fitogênicos/uso terapêutico , Crise Blástica/tratamento farmacológico , Crise Blástica/genética , Crise Blástica/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Sinergismo Farmacológico , Etoposídeo/agonistas , Etoposídeo/uso terapêutico , Humanos , Proteínas I-kappa B/biossíntese , Proteínas I-kappa B/genética , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Mutação , NF-kappa B/metabolismo , Proteína bcl-X/biossíntese
6.
Leukemia ; 20(6): 1103-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16541144

RESUMO

Mutations in exon 12 of the nucleophosmin (NPM1) gene occur in about 60% of adult AML with normal karyotype. By exploiting a specific feature of NPM1 mutants, that is insertion at residue 956 or deletion/insertion at residue 960, we developed highly sensitive, real-time quantitative (RQ) polymerase chain reaction (PCR) assays, either in DNA or RNA, that are specific for various NPM1 mutations. In all 13 AML patients carrying NPM1 mutations at diagnosis, cDNA RQ-PCR showed >30 000 copies of NPM1-mutated transcript. A small or no decrease in copies was observed in three patients showing partial or no response to induction therapy. The number of NPM1-mutated copies was markedly reduced in 10 patients achieving complete hematological remission (five cases: <100 copies; five cases: 580-5046 copies). In four patients studied at different time intervals, the number of NPM1 copies closely correlated with clinical status and predicted impending hematological relapse in two. Thus, reliable, sensitive RQ-PCR assays for NPM1 mutations can now monitor and quantify MRD in AML patients with normal karyotype and NPM1 gene mutations.


Assuntos
Dosagem de Genes , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Neoplasia Residual/diagnóstico , Neoplasia Residual/genética , Proteínas Nucleares/genética , Doença Aguda , Análise Mutacional de DNA/métodos , Perfilação da Expressão Gênica , Humanos , Mutação , Nucleofosmina , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
7.
Leukemia ; 18(11): 1824-30, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15318246

RESUMO

We compared quantitative reverse transcriptase polymerase chain reaction (Q-RT-PCR) to qualitative RT-PCR in determining response to therapy and predicting clinical outcome in 18 retrospectively selected patients with ALL positive for the ALL1-AF4 fusion and with frozen RNA samples collected at diagnosis and during follow-up (96 samples analysed). The ALL1-AF4 junction was detected by qualitative RT-PCR in 18 patients and by Q-RT-PCR in 17 patients (one patient harboured the rare e10-e6 ALL1-AF4 junction, which falls outside of the primer and probe location designed for the Q-RT-PCR). In three of the 12 patients negative to qualitative RT-PCR after induction therapy, a small number of ALL1-AF4 copies was detected by Q-RT-PCR. Thus nine patients were negative and eight positive. Seven of the eight positive patients suffered a relapse, including two of the three patients positive to Q-RT-PCR yet negative to qualitative RT-PCR. Moreover, we found two (5%) discordant results among the 39 follow-up tests of the nine patients who converted to a negative qualitative-quantitative PCR status. The results suggest that qualitative RT-PCR is more appropriate for the routine diagnosis of this genetic alteration. However, Q-RT-PCR is more accurate in assessing the molecular response after induction treatment and could be more useful in clinical decision-making in ALL1-AF4-positive ALL patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Sequência de Bases , Transplante de Medula Óssea , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Monitorização Fisiológica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Indução de Remissão , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico
9.
Leukemia ; 17(12): 2474-86, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14562124

RESUMO

Real-time quantitative RT-PCR (RQ-PCR) is a sensitive tool to monitor minimal residual disease (MRD) in leukemic patients through the amplification of a fusion gene (FG) transcript. In order to correct variations in RNA quality and quantity and to calculate the sensitivity of each measurement, a control gene (CG) transcript should be amplified in parallel to the FG transcript. To identify suitable CGs, a study group within the Europe Against Cancer (EAC) program initially focused on 14 potential CGs using a standardized RQ-PCR protocol. Based on the absence of pseudogenes and the level and stability of the CG expression, three genes were finally selected: Abelson (ABL), beta-2-microglobulin (B2M), and beta-glucuronidase (GUS). A multicenter prospective study on normal (n=126) and diagnostic leukemic (n=184) samples processed the same day has established reference values for the CG expression. A multicenter retrospective study on over 250 acute and chronic leukemia samples obtained at diagnosis and with an identified FG transcript confirmed that the three CGs had a stable expression in the different types of samples. However, only ABL gene transcript expression did not differ significantly between normal and leukemic samples at diagnosis. We therefore propose to use the ABL gene as CG for RQ-PCR-based diagnosis and MRD detection in leukemic patients. Overall, these data are not only eligible for quantification of fusion gene transcripts, but also for the quantification of aberrantly expressed genes.


Assuntos
Leucemia/diagnóstico , Leucemia/genética , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Arquivos , DNA Complementar , Europa (Continente) , Regulação Leucêmica da Expressão Gênica , Humanos , Proteínas de Fusão Oncogênica/genética , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Sensibilidade e Especificidade , Transcrição Gênica
10.
Leukemia ; 16(10): 2115-21, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12357365

RESUMO

In order to verify if quantitative assessment of the WT1 transcript amount by the real time quantitative PCR (RQ-PCR) can be used as a marker for minimal residual disease detection, the WT1 transcript amount was determined in BM and PB samples of patients with myeloid and lymphoid acute leukemia, in normal controls, in regenerating bone marrow samples and in purified CD34-positive cells from normal subjects. In 10 patients bearing a fusion gene transcript suitable for minimal residual disease quantitative assessment, we performed a simultaneous analysis of the WT1 and of the fusion-gene transcript at sequential time intervals during follow-up. Sequential WT1 analysis was also performed in five AML patients lacking additional molecular markers. The data obtained show that normal and regenerating BM samples and purified CD34-positive cells consistently express minimal amounts of WT1 transcript and that this is extremely low and frequently undetectable in normal PB. By contrast, high levels of WT1 expression are present in the BM and PB samples of all acute leukemia (AL) cases at diagnosis. The WT1 levels during follow-up were found to follow the pattern of the other molecular markers (fusion gene transcripts) used for MRD monitoring and increased WT1expression in the BM and/or PB during follow-up of AL patients was always found to be predictive of an impending hematological relapse.


Assuntos
Leucemia Mieloide Aguda/genética , Neoplasia Residual , Reação em Cadeia da Polimerase/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas WT1/genética , Sequência de Bases , Primers do DNA , Marcadores Genéticos , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , RNA Mensageiro/genética
11.
Leukemia ; 16(6): 1176-81, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12040450

RESUMO

The inv(16)(p13q22) chromosomal rearrangement associated with FAB M4Eo acute myeloid leukemia (AML) subtype is characterized by the presence of the CBFbeta/MYH11 fusion transcript that can be used to detect minimal residual disease (MRD). However, qualitative RT-PCR studies of MRD have so far produced conflicting results and seem of limited prognostic value. We have evaluated retrospectively MRD in a large series of CBFbeta/MYH11-positive patients employing both qualitative and quantitative (real-time PCR) approaches. 186 bone marrow samples from 36 patients were examined with a median follow-up of 27.5 months; 15 patients relapsed during follow-up. In qualitative studies, carried out by 'nested' RT-PCR assay, all patients in complete remission (CR) immediately after induction/consolidation therapy were found to be PCR positive. However, follow-up samples at later time points were persistently negative (except one case) in patients remaining in continuous CR (CCR) for more than 12 months. 16 patients were evaluated by quantitative real-time PCR assay: CBFbeta/MYH11 transcript copy number was normalized for expression of the housekeeping gene ABL, expressed as fusion gene copy number per 10(4) copies of ABL. A 2-3 log decline in leukemic transcript copy number was observed after induction/consolidation therapy. After achieving CR, the mean copy number was significantly higher in patients destined to relapse compared to patients remaining in CCR (151 vs 9, P < 0.0001 by Mann-Whitney test). Moreover, in CCR patients, the copy number dropped below the detection threshold after the treatment protocol was completed and remained undetectable in subsequent MRD analysis in accordance with results obtained by qualitative RT-PCR. On the contrary, in the seven patients who relapsed, the copy number in CR never declined below the detection threshold; thus a cut-off value discriminating these two groups of patients could be established. The findings of our study, if confirmed, might confer an important predictive value to quantitative real-time PCR determinations of MRD in patients with inv(16) leukemia.


Assuntos
Proteínas de Fusão Oncogênica/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , RNA Neoplásico/análise , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento
13.
Br J Haematol ; 111(2): 644-6, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11122114

RESUMO

We identified a novel BCR-ABL transcript in a chronic myelogenous leukaemia (CML) patient who relapsed after bone marrow transplantation (BMT), containing a fusion between part of BCR exon 3, 44 nucleotides derived from ABL intron 1b and ABL exon 2. The breakpoints were located within BCR exon 3 on chromosome 22 and within the ABL intron 1b on chromosome 9, and the transcript derives from a splicing of ABL exon 2 to a putative splicing acceptor site 44 nucleotides downstream to the breakpoint on chromosome 9. The patient's clinical course strengthens the idea that short forms of BCR-ABL transcripts are associated with a more aggressive disease.


Assuntos
Proteínas de Fusão bcr-abl/genética , Rearranjo Gênico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Adulto , Transplante de Medula Óssea , Perfilação da Expressão Gênica , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/cirurgia , Masculino , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Leukemia ; 13(12): 1901-28, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10602411

RESUMO

Prospective studies on the detection of minimal residual disease (MRD) in acute leukemia patients have shown that large-scale MRD studies are feasible and that clinically relevant MRD-based risk group classification can be achieved and can now be used for designing new treatment protocols. However, multicenter international treatment protocols with MRD-based stratification of treatment need careful standardization and quality control of the MRD techniques. This was the aim of the European BIOMED-1 Concerted Action 'Investigation of minimal residual disease in acute leukemia: international standardization and clinical evaluation' with participants of 14 laboratories in eight European countries (ES, NL, PT, IT, DE, FR, SE and AT). Standardization and quality control was performed for the three main types of MRD techniques, ie flow cytometric immunophenotyping, PCR analysis of antigen receptor genes, and RT-PCR analysis of well-defined chromosomal aberrations. This study focussed on the latter MRD technique. A total of nine well-defined chromosome aberrations with fusion gene transcripts were selected: t(1;19) with E2A-PBX1, t(4;11) with MLL-AF4, t(8;21) with AML1-ETO, t(9;22) with BCR-ABL p190 and BCR-ABL p210, t(12;21) with TEL-AML1, t(15;17) with PML-RARA, inv (16) with CBFB-MYH11, and microdeletion 1p32 with SIL-TAL1. PCR primers were designed according to predefined criteria for single PCR (external primers A <--> B) and nested PCR (internal primers C <--> D) as well as for 'shifted' PCR with a primer upstream (E5' primer) or downstream (E3' primer) of the external A <--> B primers. The 'shifted' E primers were designed for performing an independent PCR together with one of the internal primers for confirmation (or exclusion) of positive results. Various local RT and PCR protocols were compared and subsequently a common protocol was designed, tested and adapted, resulting in a standardized RT-PCR protocol. After initial testing (with adaptations whenever necessary) and approval by two or three laboratories, the primers were tested by all participating laboratories, using 17 cell lines and patient samples as positive controls. This testing included comparison with local protocols and primers as well as sensitivity testing via dilution experiments. The collaborative efforts resulted in standardized primer sets with a minimal target sensitivity of 10-2 for virtually all single PCR analyses, whereas the nested PCR analyses generally reached the minimal target sensitivity of 10-4. The standardized RT-PCR protocol and primer sets can now be used for molecular classification of acute leukemia at diagnosis and for MRD detection during follow-up to evaluate treatment effectiveness.


Assuntos
Aberrações Cromossômicas , Leucemia/genética , Proteínas de Fusão Oncogênica/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Doença Aguda , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia/diagnóstico , Neoplasia Residual
17.
Leukemia ; 11(6): 820-1, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9177434

RESUMO

Individuals with constitutional trisomy 21 (Down syndrome) are at increased risk of developing acute leukaemias, both of myeloid and lymphoid lineage. Although the cause of leukaemia in Down syndrome (DS) remains unknown, potential candidate genes include the ones on chromosome 21, and in particular AML1, the rearrangement of which in the t(8,21) is associated with the French-American-British (FAB) classification M2 subtype of acute myeloid leukaemia (AML) in the general population and has been described in Down patients with AML-M2. Recently, a new rearrangement involving AML1, the t(12;21), producing the TEL/AML1 hybrid transcript, has been described by molecular analysis as the most recurrent genetic lesion in childhood acute lymphoblastic leukemia (ALL). In order to investigate whether the t(12;21) could give a molecular clue as to the precise basis of the etiologic association between DS and acute lymphoblastic leukemia, we tested a series of 11 consecutive cases of ALL in DS children for the presence of the TEL/AML1 transcript, by RT-PCR analysis. We report absence of the TEL/AML1 rearrangement among the 11 cases tested. This data may be suggestive of alternative pathways involved in the pathogenesis of ALL in children with constitutional trisomy 21.


Assuntos
Proteínas de Ligação a DNA/genética , Síndrome de Down/genética , Rearranjo Gênico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Repressoras , Fatores de Transcrição/genética , Adolescente , Criança , Pré-Escolar , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA/biossíntese , Síndrome de Down/complicações , Humanos , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-ets , Fatores de Transcrição/biossíntese , Transcrição Gênica , Variante 6 da Proteína do Fator de Translocação ETS
18.
Br J Haematol ; 97(2): 460-2, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9163615

RESUMO

The t(12;21)(p13;q22) translocation has been described recently as the most recurrent genetic lesion in paediatric acute lymphoblastic leukaemias (ALLs). It has also been associated with B-precursor lineage involvement and good outcome. We tested 51 diagnostic paediatric ALLs and found 11 cases with molecular evidence of the t(12;21). Interestingly, amongst t(12;21) positive patients, we report three cases with hybrid phenotype, and two cases showing an aggressive and fatal disease. Our data show that the t(12;21) does not represent an independent good-risk indicator. Long follow-ups and additional molecular investigations are needed to assess the prognostic and pathogenetic relevance of t(12;21) in childhood ALLs.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 21 , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética , Linhagem da Célula , Criança , Pré-Escolar , Feminino , Humanos , Imunofenotipagem , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Prognóstico
19.
Leukemia ; 11 Suppl 3: 519-21, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9209443

RESUMO

Chronic myelogenous leukemia presents two distinct clinical phases: the chronic phase is characterised by a marked expansion of the myeloid compartment which still retains a normal differentiative capacity, whereas a differentiation block is the clinical hallmark of the acute transformation. The molecular mechanism underlying the CML progression are still poorly understood. The occurrence of additional molecular lesions, involving the p53, the RAS and the p16 genes may complement and fulfil the BCR/ABL transforming potential, finally leading to an acute leukemic phenotype. However, several lines of evidence suggest that also quantitative changes of the BCR/ABL transcript amounts could explain the progression of the leukemic phenotype in the BCR/ABL-positive hematologic malignancies.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/fisiopatologia , Mapeamento Cromossômico , Cromossomos Humanos Par 9 , Progressão da Doença , Proteínas de Fusão bcr-abl/biossíntese , Deleção de Genes , Genes Supressores de Tumor , Genes p53 , Genes ras , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/fisiopatologia , Humanos , Fenótipo , Transcrição Gênica
20.
J Med Microbiol ; 45(2): 84-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8683556

RESUMO

Cytotoxic strains of Helicobacter pylori cause an intense vacuolar degeneration of cells, due to the enlargement of late endosomes in the presence of membrane permeant weak bases. Bafilomycins, specific inhibitors of the vacuolar-type (V-) ATPase proton pump, prevent vacuole formation. The presence of the V-ATPase on vacuolar membranes was demonstrated by immunofluorescence with a monoclonal antibody (MAb) specific for the human 116-kDa regulatory subunit. The V-ATPase co-localised with the late endosomal marker rab7 on vacuolar membranes. In contrast, the early recycling endosomal compartment was not altered by the VacA cytotoxin, although it was endowed with the V-ATPase. Endocytosis of a MAb against the 116-kDa regulatory subunit of V-ATPase blocked endosomal acidification in HeLa cells and prevented VacA action. These results indicate that selective swelling of late endosomes, due to accumulation of osmotically active weak bases driven by the V-ATPase, is essential for vacuole formation.


Assuntos
Adenosina Trifosfatases/análise , Helicobacter pylori/fisiologia , Bombas de Próton/fisiologia , Vacúolos/enzimologia , Adenosina Trifosfatases/imunologia , Animais , Anticorpos Monoclonais , Proteínas de Bactérias/farmacologia , Citotoxinas/farmacologia , Técnica Indireta de Fluorescência para Anticorpo , Cobaias , Células HeLa , Helicobacter pylori/patogenicidade , Humanos , Soros Imunes , Membranas Intracelulares/enzimologia , Camundongos , Coelhos , Vacúolos/efeitos dos fármacos , Vacúolos/ultraestrutura
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