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1.
Transpl Infect Dis ; 17(6): 822-30, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26354178

RESUMO

BACKGROUND: Hemorrhagic cystitis (HC) is a common complication after hematopoietic allogeneic stem cell transplantation (HSCT) associated with intensity of the conditioning regimen, cyclophosphamide (Cy) therapy, and BK polyomavirus (BKPyV) infection. METHODS: We analyzed 33 consecutive haploidentical (haplo) HSCT recipients transplanted for hematologic diseases. Eleven patients had a previous transplant. Median follow-up was 11 months. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine + mycophenolate mofetil and post-HSCT Cy. RESULTS: Thirty-two of 33 patients achieved neutrophil recovery. Cumulative incidence (CI) of platelet recovery was 65%. CI grade II-IV acute GVHD was 44%. Twenty patients developed HC in a median time of 38 days. CI of HC at day 180 was 62%. BKPyV was positive in blood and urine of 91% of patients at HC onset. HC resolved in 18/20 patients. Factors associated with HC were previous transplant (P = 0.01) and occurrence of cytomegalovirus reactivation before HC (P = 0.05). Grade II-IV acute GVHD was not associated with HC (P = 0.62). CI of day 180 viral infections was 73%. Two-year overall survival (OS) was 50%; HC did not impact OS (P = 0.29). CONCLUSION: The incidence of HC after haplo with post-HSCT Cy is high and is associated with morbidity, especially in high-risk patients such as those with a previous transplant history and with impaired immune reconstitution.


Assuntos
Cistite/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Adulto , Idoso , Doença Enxerto-Hospedeiro/prevenção & controle , Haplótipos , Hemorragia , Humanos , Imunossupressores/farmacologia , Incidência , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
2.
Phys Rev Lett ; 113(22): 224101, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25494073

RESUMO

The change of resonance widths in an open system under a perturbation of its interior has been recently introduced by Fyodorov and Savin [Phys. Rev. Lett. 108, 184101 (2012)] as a sensitive indicator of the nonorthogonality of resonance states. We experimentally study universal statistics of this quantity in weakly open two-dimensional microwave cavities and reverberation chambers realizing scalar and electromagnetic vector fields, respectively. We consider global as well as local perturbations, and also extend the theory to treat the latter case. The influence of the perturbation type on the width shift distribution is more pronounced for many-channel systems. We compare the theory to experimental results for one and two attached antennas and to numerical simulations with higher channel numbers, observing a good agreement in all cases.

3.
Leukemia ; 21(6): 1172-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17429427

RESUMO

More than 30 years ago it was discovered that permeability glycoprotein (P-gp) can cause drug resistance. Over the following decades numerous studies showed that high expression of P-gp is associated with poor prognosis in acute myeloid leukemia in adults and that it causes multidrug resistance via ATP-dependent drug efflux. It was hoped that an inhibition of P-gp could sensitize resistant leukemic cells to chemotherapy and thus improve treatment results. Today we know that the family of ATP-binding cassette transporters (ABC transporters) comprises 48 different proteins. Some of them seem to be able to cause drug resistance as well as P-gp. This review focuses on emerging data on the clinical relevance of other ABC transporters, such as BCRP, MRP3, and ABCA3. When Heracles fought the ancient Hydra, he had to fight all the heads at ones but only one head was vital for the beast. Can we block all the relevant ABC transporters at once? Is there one transporter that is more important than the others?


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Transportadores de Cassetes de Ligação de ATP/fisiologia , Resistência a Medicamentos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Humanos , Leucemia/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Proteínas de Neoplasias
4.
Leukemia ; 21(1): 66-71, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17051246

RESUMO

Pivotal phase II studies in acute myeloblastic leukemia (AML) patients in first relapse have used gemtuzumab ozogamicin (GO) (Mylotarg) at a dose of 9 mg/m(2) on days 1 and 14. These studies showed a 26% response rate (13% complete remission (CR) and 13% CRp (complete remission with incomplete platelet recovery)) but with high degree of hematological and liver toxicities. Based on in vitro studies showing a re-expression of CD33 antigenic sites on the cell surface of blasts cells after exposure to GO, we hypothesized that fractionated doses of GO may be efficient and better tolerated. Fifty-seven patients with AML in first relapse received GO at a dose of 3 mg/m(2) on days 1, 4 and 7 for one course. Fifteen patients (26%) achieved CR and four (7%) CRp. Remission rate correlated strongly with P-glycoprotein and MRP1 activities. The median relapse-free survival was 11 months, similar for CR or CRp patients. Median duration of neutropenia < 500/microl and thrombocytopenia < 50,000/microl were, respectively, 23 and 21 days. No grade 3 or 4 liver toxicity was observed. No veno-occlusive disease occurred after GO or after hematopoietic stem cell transplantation given after GO in seven patients. Mylotarg administered in fractionated doses demonstrated an excellent efficacy/safety profile.


Assuntos
Aminoglicosídeos/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminoglicosídeos/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Antineoplásicos/efeitos adversos , Intervalo Livre de Doença , Esquema de Medicação , Gemtuzumab , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/sangue , Recidiva , Indução de Remissão , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
5.
Leukemia ; 20(9): 1526-32, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16838024

RESUMO

Acute lymphoblastic leukemia (ALL) in the elderly is characterized by its ominous prognosis. On the other hand, imatinib has demonstrated remarkable, although transient, activity in relapsed and refractory Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL), which prompted us to assess the use of imatinib in previously untreated elderly patients. ALL patients aged 55 years or older were given steroids during 1 week. Ph+ve cases were then offered a chemotherapy-based induction followed by a consolidation phase with imatinib and steroids during 2 months. Patients in complete response (CR) after consolidation were given 10 maintenance blocks of alternating chemotherapy, including two additional 2-month blocks of imatinib. Thirty patients were included in this study and are compared with 21 historical controls. Out of 29 assessable patients, 21 (72%, confidence interval (CI): 53-87%) were in CR after induction chemotherapy vs 6/21 (29%, CI: 11-52%) in controls (P=0.003). Five additional CRs were obtained after salvage with imatinib and four after salvage with additional chemotherapy in the control group. Overall survival (OS) is 66% at 1 year vs 43% in the control group (P=0.005). The 1-year relapse-free survival is 58 vs 11% (P=0.0003). The use of imatinib in elderly patients with Ph+ ALL is very likely to improve outcome, including OS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Metilprednisolona/uso terapêutico , Cromossomo Filadélfia , Piperazinas/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Pirimidinas/uso terapêutico , Resultado do Tratamento , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzamidas , Intervalo Livre de Doença , Humanos , Mesilato de Imatinib , Metilprednisolona/administração & dosagem , Piperazinas/administração & dosagem , Pirimidinas/administração & dosagem , Transplante de Células-Tronco
6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(3 Pt 1): 031925, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16605576

RESUMO

The dc electrical conductivity of double stranded DNA is investigated experimentally. Single DNA molecules are manipulated with subpiconewton force and deposited on gold nanoelectrodes by optical traps. The DNA is modified at its ends for specific bead attachments and along the chain to favor charge transfer between the DNA base pair stack and the electrodes. For an electrode separation of 70 nm we find, in aqueous environment, electrical resistances above 100 G Omega indicating that even for weak stretching the double helix is almost insulating at this length scale.


Assuntos
DNA/química , Eletroquímica/métodos , Modelos Químicos , Água/química , Simulação por Computador , Elasticidade , Condutividade Elétrica , Estresse Mecânico
7.
Phys Rev E ; 93(3): 032108, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27078293

RESUMO

The effective Hamiltonian formalism is extended to vectorial electromagnetic waves in order to describe statistical properties of the field in reverberation chambers. The latter are commonly used in electromagnetic compatibility tests. As a first step, the distribution of wave intensities in chaotic systems with varying opening in the weak coupling limit for scalar quantum waves is derived by means of random matrix theory. In this limit the only parameters are the modal overlap and the number of open channels. Using the extended effective Hamiltonian, we describe the intensity statistics of the vectorial electromagnetic eigenmodes of lossy reverberation chambers. Finally, the typical quantity of interest in such chambers, namely, the distribution of the electromagnetic response, is discussed. By determining the distribution of the phase rigidity, describing the coupling to the environment, using random matrix numerical data, we find good agreement between the theoretical prediction and numerical calculations of the response.

8.
Leukemia ; 13(4): 578-84, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10214864

RESUMO

The best characterized resistance mechanism in adult acute myeloid leukemia (AML) is the one mediated by the MDR1 gene which has been shown to be associated with poor outcome. However, alternative proteins such as the more recently recognized multidrug-associated protein (MRP1), may also contribute to the resistance to anthracyclines and etoposide in AML. Recently, the role of this protein was discussed and was unclear in AML. However, recent data concerning the functionality and the modulation of the activity of MRP1 may elucidate its role in comparison with other mechanisms of resistance. In this paper, we will review these recent data concerning the role of MRP1 in adult AML.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Proteínas de Neoplasias/fisiologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Doença Aguda , Adulto , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Cromossomos Humanos Par 16/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Etoposídeo/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Leucemia Mieloide/mortalidade , Proteína 3 Homóloga a MutS , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Prognóstico
9.
Leukemia ; 12(9): 1367-74, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9737684

RESUMO

The role of LRP in clinical drug resistance in acute myeloid leukemia (AML) is controversial. We therefore compared multiple assays, including RT-PCR, immunocytochemistry (ICC) and flow cytometry (FC), in 10 cell lines and in 47 fresh and thawed AML cells in order to validate and to quantitate measures for LRP phenotype detection. We also compared different ways of expressing the results. Lastly, in cell lines, we analyzed the 50% lethal concentration (LC50), by MTT assay, of cisplatin which could estimate the functionality of LRP. The reproducibility of LRP detection measured by RT-PCR, ICC and FC was good. In the same way, within the same technique, there was good correlation between the different methods of expressing the results of LRP level. Therefore, the discrepancies noted with the three techniques used were neither a problem of reproducibility nor a problem of results expression. On the other hand, there was only a correlation between ICC and FC, and no correlation between RT-PCR and LRP protein detection techniques. Therefore, RT-PCR is probably not the optimal technique for LRP detection. We have shown in 10 cell lines a higher correlation between FC and LC50 of cisplatin than between ICC and LC50 of cisplatin and no correlation between RT-PCR and LC50 of cisplatin. For five patients, there was a dissociation between ICC and FC. Four patients were positive by FC and negative by ICC and only one patient was negative by FC and positive by ICC. Therefore, if in vitro resistance to cisplatin represents the functionality of LRP, we recommend the use of FC rather than ICC to detect LRP expression. Besides the measurement of LRP as a diagnostic tool in the evaluation of resistance to chemotherapy in patients with AML, we urgently need to establish a functional test in order to assess LRP activity.


Assuntos
Leucemia Mieloide/metabolismo , Proteínas de Neoplasias/metabolismo , Partículas de Ribonucleoproteínas em Forma de Abóbada , Doença Aguda , Adulto , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Fenótipo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Células Tumorais Cultivadas/efeitos dos fármacos
10.
Leukemia ; 18(4): 670-5, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14762443

RESUMO

Acute respiratory failure and infectious pneumonia are the major causes of death during induction chemotherapy of acute leukemia. However, the causes, incidence and prognostic value of all respiratory events (REs) occurring in this context have never been assessed prospectively. We recruited 65 consecutive patients with newly diagnosed acute leukemia into a 1-year prospective study (December 2000-November 2001) to evaluate the incidence and prognostic value of these events. REs were frequent: 38 were recorded in 30 patients. There was a significant relationship between REs and pre-existing respiratory disease and/or smoking. REs were caused by infection in 34% of cases, by an established cause other than infection in 42% and had an undetermined cause in 24%. Poor early outcome (death within 45 days of starting induction chemotherapy) in patients experiencing an RE was independently associated with a >25/min respiratory rate (P=0.003) and the nonachievement of complete remission (CR) (P<0.0001). Predictors of overall survival in the entire patient population were the absence of CR (P<0.0001), REs (P=0.02) and a > or =2 performance status (P=0.03). In conclusion, REs are frequent during induction chemotherapy of acute leukemia and represent an independent prognostic factor of poor outcome, regardless of their cause.


Assuntos
Leucemia/complicações , Leucemia/diagnóstico , Transtornos Respiratórios/etiologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Infecciosos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Incidência , Leucemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Indução de Remissão , Transtornos Respiratórios/epidemiologia , Fatores de Risco , Taxa de Sobrevida
11.
Leukemia ; 18(7): 1246-51, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15116123

RESUMO

The multidrug resistance (MDR) phenotype, induced by the overexpression of several ABC transporters or by antiapoptotic mechanisms, has been identified as the major cause of drug resistance in the treatment of patients with acute myeloid leukemia (AML). In this study, we have shown that valproic acid (VPA) (a histone deacetylase inhibitor) can inhibit the proliferation of both P-glycoprotein (P-gp)- and MDR-associated protein 1 (MRP1)-positive and -negative cells. VPA also induced apoptosis of P-gp-positive cells. VPA induced apoptosis in K562 cells led to decrease in Flip (FLICE/caspase-8 inhibitory protein) expression with Flip cleavage, which could not be observed in HL60 cells. In HL60/MRP cell line, which proved to be resistant to apoptosis by VPA, we observed an abnormal expression of apoptotic regulatory proteins, overexpression of Bcl-2 and absence of Bax. Also, the Bcl-2 antagonist HA14-1 rapidly restored apoptosis in this cell line. Cotreatment with cytosine arabinoside induced very strong apoptosis in both K562/DOX and HL60/DNR cell lines. VPA also induced apoptosis in AML patient cells expressing P-gp and/or MRP1. Our findings show VPA as an interesting drug that should be tested in clinical trials for overcoming the MDR phenotype in AML patients.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Apoptose/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/análise , Ácido Valproico/farmacologia , Doença Aguda , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD , Proteínas de Transporte/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Citarabina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Células Tumorais Cultivadas
12.
Leukemia ; 9(10): 1742-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7564519

RESUMO

Chronic B cell lymphoproliferative disorders are frequently sensitive to alkylating agents. To assess the glutathione-S-transferases (GSTs) gene expression in B tumoral lymphocytes, possibly responsible for this sensitivity, we developed a sensitive RT-PCR assay for the three isoenzymes GST pi, GST mu and GST alpha mRNA. Normal B and T lymphocytes from 11 blood donors were separated by magnetic beads and tested with this assay. The GST pi was the most abundant transferase, and was detected in all B and T cell samples. GST mu was undetectable ('null' phenotype) in 6/11 normal donors, either in B or T cells. GST alpha was very stable from donor to donor, and was highly correlated between B and T cells of the same individual (P < 0.0001). There is no correlation between the three isoenzymes, and between each isoenzyme and mdr1 gene expression. Twenty-three B lymphoproliferative disorders (20 B-CLL, 3 CD5- chronic lymphoproliferative syndromes) were tested with the same technique. An average decrease of 57% of the GST pi expression was noted in the mononuclear cells of these patients (P < 0.02), with no differences between the untreated and treated cases. The GST alpha and mdr1 mRNA levels did not differ from normal B lymphocytes, but the proportion of patients with no detectable expression of GST mu is lower than in the control (13%). Interestingly, the low content of GST pi in B-CLL could explain the frequent sensitivity of this disease to alkylating agents.


Assuntos
Linfócitos B/enzimologia , Resistência a Múltiplos Medicamentos , Glutationa Transferase/análise , Isoenzimas/análise , Leucemia Linfocítica Crônica de Células B/enzimologia , RNA Mensageiro/análise , Linfócitos T/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Linhagem Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
13.
Semin Hematol ; 34(4 Suppl 5): 63-71, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9408962

RESUMO

Before the prognostic significance of P-glycoprotein (P-gp) expression can be properly evaluated in prospective clinical trials of P-gp modulators, standard techniques for the measurement of P-gp must be widely accepted. Several multicenter trials have demonstrated large discrepancies in the observed levels of P-gp expression in the same clinical samples evaluated at different centers. The greatest discrepancies occurred with samples that expressed low levels of P-gp. Although standardized procedures have dramatically increased the interlaboratory reproducibility of flow cytometry and polymerase chain reaction assays, data from immunocytochemistry remain difficult to interpret. Consensus recommendations are presented for improving data reproducibility. These recommendations emphasize the importance of using calibrated batches of antibodies and two different antibodies for immunocytochemistry, the need for an internal standard for reverse transcriptase-polymerase chain reaction (RT-PCR) assays, the need for the presentation of data as a continuous variable, and the need for setting standard parameters for flow cytometry. It is also extremely important for the success of clinical trials that multiple techniques be employed to insure accurate measurement of P-gp expression.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Neoplasias/genética , Antineoplásicos/uso terapêutico , Conferências de Consenso como Assunto , Humanos , Estudos Multicêntricos como Assunto , Neoplasias/tratamento farmacológico
14.
NMR Biomed ; 13(2): 102-107, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10797638

RESUMO

In order to keep subscribers up-to-date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 9 sections: 1 Books, Reviews ' Symposia; 2 General; 3 Technology; 4 Brain and Nerves; 5 Neuropathology; 6 Cancer; 7 Cardiac, Vascular and Respiratory Systems; 8 Liver, Kidney and Other Organs; 9 Muscle and Orthopaedic. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted.

15.
Leuk Lymphoma ; 34(5-6): 561-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10492080

RESUMO

Out of 75 consecutive elderly AML patients who did not receive anti-leukemic treatment (52 pts) or failed to respond to differentiating agent (23 pts), 6 patients had survivals of 13.2 to 98 months with treatment restricted to supportive care. This cut-point is far longer than the median survival of the 235 elderly patients (3.5 mo.), either untreated (med. survival: 1 mo.) or treated (with treatment ranging from conventional induction to palliative chemotherapy) (4 mo.), admitted to our department within the same period of time. These cases of smoldering AML (4 women, 2 men) were all of AML2 FAB subtype (4 de novo, 2 post MDS) and presented with a significantly better performance status, lower WBC and circulating blast counts, higher platelet counts and with lower bone marrow infiltration than AML cases with more rapid progression. Cytogenetical analysis when available (3 pts) showed normal karyotypes and clonogenic assay performed in 3 of these patients showed a lack of (2 pts) or reduced in vitro leukemic cell growth (1 pt). The identification of specific characteristics of smoldering leukemia in the elderly might be an important development in the understanding of the physiopathology of acute leukemia and a tool for helping decision-making when selecting the time and intensity of cytotoxic treatment in these older patients.


Assuntos
Anemia Refratária com Excesso de Blastos/diagnóstico , Leucemia Mieloide Aguda/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária com Excesso de Blastos/mortalidade , Anemia Refratária com Excesso de Blastos/patologia , Crise Blástica/patologia , Exame de Medula Óssea , Progressão da Doença , Evolução Fatal , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Taxa de Sobrevida , Sobreviventes
16.
Leuk Lymphoma ; 15(5-6): 433-8, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7874000

RESUMO

Prognostic factors in acute lymphoblastic leukemia (ALL) are used for treatment stratification of ALL. Definition of simple parameters such as the presence or absence of peripheral leukemic cells after one week of treatment could help for stratification. A retrospective study was conducted on 79 previously untreated adult patients with ALL followed in the Hematology department of Hotel Dieu from 1981 to 1991. 84% of patients achieved complete remission (CR), 7% were refractory to induction treatment, and 7 patients (9%) died during the first month after diagnosis. After multivariate analysis the only independent statistically significant factors for achieving CR were the absence of peripheral blast cells at day 7 (PBC D7) (p = 0.009) and age (< 50 years) (p = 0.03). For CR duration the same independent statistically significant factors were found (PBC D7 = 0 versus > 0, p = 0.008; and age < or > or = 30 years, p = 0.045). The PBC D7 value was more significant when circulating blast cells were present at diagnosis. In patients with more than 50,000 PBC at diagnosis, the 10- years event free disease was 62% +/- 20% when PBC were absent at day 7 versus 0% when PBC were present (p < 0.002). All 20 patients with prolonged DFS had PBC D7 = 0 achieving CR by 28 days. The persistence of PBC at Day 7 could be used as a factor to identify a subgroup of poor prognosis adults with ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Indução de Remissão , Estudos Retrospectivos , Fatores de Tempo
17.
Leuk Lymphoma ; 8(4-5): 261-5, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1363283

RESUMO

Sequential evaluation of P-glycoprotein expression was performed in 29 patients with acute nonlymphoblastic leukemia using immunocytochemistry with the C219 antibody. At diagnosis, 32% of the patients exhibited more than 5% of the P-gp(+) leukemic cells. Under chemotherapy, 62% of the patients eventually expressed a subset of P-gp positive leukemic cells. After conventional doses of cytosine-arabinoside (Ara-C) and daunorubicin or mitoxantrone, positive P-gp cells were noted in 65% of the cases. This percentage was significantly higher (p = 0.002) than the proportion of positive cases (15%) observed after regimens containing either intermediate doses of Ara-C or cyclosporine A, a P-gp modulator.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Glicoproteínas de Membrana/biossíntese , Proteínas de Neoplasias/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Adulto , Idoso , Amsacrina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Proteínas de Neoplasias/genética , Indução de Remissão
18.
Adv Exp Med Biol ; 457: 1-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10500774

RESUMO

P-glycoprotein (P-gp) is often expressed (40-50%) on leukemic cells at diagnosis in acute myelogenous leukemia (AML), and is even more frequently present after treatment failure. Several large cohorts of newly diagnosed AML patients treated with a classical anthracycline + standard doses of cytosine arabinoside were tested for the prognosis value of MDR1 phenotype, and demonstrated an high correlation between a significant increase of MDR1 gene expression and treatment failure (or, better, drug resistance). This P-gp(+) drug resistance could be due either to a particular phenotype of bad prognosis AML, as it is suggested by the association of myelodysplasia, complex karyotype and advanced age with MDR1 phenotype, or due primarily to the active efflux of anthracyclines and VP16 in P-gp(+) leukemic cells. Several observations tend to confirm the functional role of the P-gp in clinical drug resistance; (i) using multivariate analysis, MDR1 phenotype appears to be an independent variable, as potent (or higher) as karyotype and age for predicting in vivo drug resistance; (ii) the prognostic value is limited to the CD34(+)/P-gp(+) phenotype, wich is linked to a functional P-gp; (iii) the in vitro sensitivity to anthracyclines and VP16 is highly correlated with P-gp expression. All these data argue for an early use of P-gp modifier agents in the treatment of AML. The role of the MDR1 gene in ALL resistance is controversial and marginal compared to the sensitivity of ALL blasts to glucocorticoids, and the frequency of MDR1 phenotype is low at diagnosis, and is increasing only after repetitive chemotherapies.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Genes MDR , Leucemia/tratamento farmacológico , Leucemia/genética , Doença Aguda , Adulto , Criança , Humanos , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prognóstico , Falha de Tratamento
19.
Adv Exp Med Biol ; 457: 161-75, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10500791

RESUMO

Thirteen cell lines with different levels of Pgp and MRP1 expression were used to assess the ability of calcein-AM uptake and calcein efflux to measure Pgp and MRP1 functions, respectively. There was a good correlation between MRP1 expression and the modulatory effect of probenecid (a specific modulator of MRP1) on the calcein efflux (r = 0.91, p = 0.0003) and between Pgp expression and the modulatory effect of CsA on calcein-AM uptake (r = 0.96, p < 0.0001). On light of the high correlations for both proteins, we tested calcein-AM uptake and efflux in fresh myeloid leukemic cells. In 53 AML patients, there was also a good correlation between MRP1 expression (measured by RT/PCR and by MRPm6 expression by flow cytometry) and the modulatory effect of probenecid on the calcein fluorescence (r = 0.92, p < 0.0001) and between Pgp expression as measured by UIC2 antibody binding on flow cytometry and the modulatory effect of CsA on calcein-AM uptake (r = 0.83, p < 0.0001). Pgp activity was higher in CD34+ leukemia than in CD34- leukemia (2.26 +/- 1.50 vs 1.46 +/- 1.21 respectively, p = 0.003) and MRP1 activity was higher in CD34- leukemia than in CD34+ leukemia (1.77 +/- 0.40 vs 1.4 +/- 0.29 respectively, p = 0.004). Pgp expression and activity (p = 0.004 and p = 0.01, respectively), MRP1 activity (p = 0.03) but not MRP1 expression were prognostic factors for achievement of CR. The effect of probenecid and CsA together were higher than the effect of either probenecid or CsA alone on calcein-AM uptake. These results suggest that functional testing (with calcein-AM +/- modulators) for the presence of both MRP1 and Pgp activities is of prognostic value and that MRP1 contributes to drug resistance in AML.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacocinética , Proteínas de Ligação a DNA/metabolismo , Resistência a Múltiplos Medicamentos , Fluoresceínas/farmacocinética , Genes MDR , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Pareamento Incorreto de Bases , Transporte Biológico/efeitos dos fármacos , Cálcio/metabolismo , Ciclosporina/farmacologia , Proteínas de Ligação a DNA/genética , Feminino , Citometria de Fluxo/métodos , Corantes Fluorescentes , Humanos , Células K562 , Masculino , Proteína 3 Homóloga a MutS , RNA Mensageiro/genética , Transcrição Gênica , Células Tumorais Cultivadas
20.
Rev Med Interne ; 34(10): 636-40, 2013 Oct.
Artigo em Francês | MEDLINE | ID: mdl-23660185

RESUMO

INTRODUCTION: Intravascular large B cell lymphoma is a neoplastic cell proliferation leading to the occlusion of the lumen of small vessels. This is a rare haematological malignancy, which is difficult to diagnose because of a heterogeneous clinical presentation. CASE REPORT: We report a 62-year-old man who presented a macrophage activation syndrome as the presenting manifestation of an intravascular lymphoma. This association is frequently marked by a greater severity and clinical care requires an early and appropriate treatment. CONCLUSION: Due to the polymorphism and the systemic presentation of intravascular large B cell lymphoma, the internist may be confronted with this disease, which is considered to be more severe if associated with a macrophage activation syndrome. Awareness of the intravascular large B cell lymphoma is important because the prognosis depends on the rapidity of the initiation of chemotherapy associated with rituximab.


Assuntos
Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/diagnóstico , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Ativação Macrofágica/etiologia , Neoplasias Vasculares/complicações , Neoplasias Vasculares/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
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