Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
2.
Leukemia ; 30(2): 285-94, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26460209

RESUMO

Risks of acute myeloid leukemia (AML) and/or myelodysplastic syndromes (MDS) are known to increase after cancer treatments. Their rise-and-fall dynamics and their associations with radiation have, however, not been fully characterized. To improve risk definition we developed SEERaBomb R software for Surveillance, Epidemiology and End Results second cancer analyses. Resulting high-resolution relative risk (RR) time courses were compared, where possible, to results of A-bomb survivor analyses. We found: (1) persons with prostate cancer receiving radiation therapy have increased RR of AML and MDS that peak in 1.5-2.5 years; (2) persons with non-Hodgkin lymphoma (NHL), lung and breast first cancers have the highest RR for AML and MDS over the next 1-12 years. These increased RR are radiation specific for lung and breast cancer but not for NHL; (3) AML latencies were brief compared to those of A-bomb survivors; and (4) there was a marked excess risk of acute promyelocytic leukemia in persons receiving radiation therapy. Knowing the type of first cancer, if it was treated with radiation, the interval from first cancer diagnosis to developing AML or MDS, and the type of AML, can improve estimates of whether AML or MDS cases developing in this setting are due to background versus other processes.


Assuntos
Leucemia Mieloide Aguda/etiologia , Síndromes Mielodisplásicas/etiologia , Segunda Neoplasia Primária/etiologia , Neoplasias/radioterapia , Feminino , Humanos , Masculino , Radioterapia/efeitos adversos , Risco
3.
Bone Marrow Transplant ; 50(12): 1513-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26301967

RESUMO

In patients with multiple myeloma (MM) undergoing autologous hematopoietic cell transplantation (auto-HCT), peripheral blood progenitor cells may be collected following mobilization with growth factor alone (GF) or cytotoxic chemotherapy plus GF (CC+GF). It is uncertain whether the method of mobilization affects post-transplant outcomes. We compared these mobilization strategies in a retrospective analysis of 968 patients with MM from the Center for International Blood and Marrow Transplant Research database who received an auto-HCT in the US and Canada between 2007 and 2012. The kinetics of neutrophil engraftment (⩾0.5 × 10(9)/L) was similar between groups (13 vs 13 days, P=0.69) while platelet engraftment (⩾20 × 10(9)/L) was slightly faster with CC+GF (19 vs 18 days, P=0.006). Adjusted 3-year PFS was 43% (95% confidence interval (CI) 38-48) in GF and 40% (95% CI 35-45) in CC+GF, P=0.33. Adjusted 3-year OS was 82% (95% CI 78-86) vs 80% (95% CI 75-84), P=0.43 and adjusted 5-year OS was 62% (95% CI 54-68) vs 60% (95% CI 52-67), P=0.76, for GF and CC+GF, respectively. We conclude that MM patients undergoing auto-HCT have similar outcomes irrespective of the method of mobilization and found no evidence that the addition of chemotherapy to mobilization contributes to disease control.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo/sangue , Mieloma Múltiplo/terapia , Adolescente , Adulto , Idoso , Autoenxertos , Intervalo Livre de Doença , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Prospectivos , Recuperação de Função Fisiológica , Taxa de Sobrevida
4.
Bone Marrow Transplant ; 50(10): 1326-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26191953

RESUMO

The relationship of socioeconomic status (SES) with long-term outcomes in allogeneic hematopoietic cell transplantation (HCT) survivors has not been well described. We studied the association of SES with the outcomes of 283 consecutive allogeneic HCT recipients transplanted between 2003 and 2012 who had survived for at least 1 year in remission. Median annual household income was estimated using Census tract data and from ZIP code of residence. SES categories were determined by recursive partitioning analysis (low SES (<$51 000/year), N=203; high SES (⩾$51 000/year), N=80). In multivariable analyses, low SES patients had higher risks of all-cause mortality (hazard ratio (HR) 1.98, P=0.012) and non-relapse mortality (NRM) (HR 2.22, P=0.028), but similar risks of relapse mortality (HR 1.01, P=0.97) compared with high SES patients. A trend toward better survival and lower NRM for high SES patients with no chronic GVHD was observed; low SES patients without GVHD had similar survival as patients with chronic GVHD. In allogeneic HCT survivors who survive in remission for at least 1 year, SES is associated with long-term survival that is primarily mediated through higher risks of NRM. More research is needed to understand the mechanisms of health-care disparities and interventions to mitigate them.


Assuntos
Transplante de Células-Tronco Hematopoéticas/economia , Classe Social , Condicionamento Pré-Transplante/economia , Transplante Homólogo/economia , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Sobreviventes , Condicionamento Pré-Transplante/mortalidade , Transplante Homólogo/mortalidade , Resultado do Tratamento , Adulto Jovem
5.
Bone Marrow Transplant ; 50(9): 1235-40, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26030045

RESUMO

Quality of life (QOL) is an important outcome for hematopoietic cell transplantation (HCT) recipients. Whether pre-HCT QOL adds prognostic information to patient and disease related risk factors has not been well described. We investigated the association of pre-HCT QOL with relapse, non-relapse mortality (NRM), and overall mortality after allogeneic HCT. From 2003 to 2012, the Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale instrument was administered before transplantation to 409 first allogeneic HCT recipients. We examined the association of the three outcomes with (1) individual QOL domains, (2) trial outcome index (TOI) and (3) total score. In multivariable models with individual domains, functional well-being (hazard ratio (HR) 0.95, P=0.025) and additional concerns (HR 1.39, P=0.002) were associated with reduced risk of relapse, no domain was associated with NRM, and better physical well-being was associated with reduced risk of overall mortality (HR 0.97, P=0.04). TOI was not associated with relapse or NRM but was associated with reduced risk of overall mortality (HR 0.93, P=0.05). Total score was not associated with any of the three outcomes. HCT-comorbidity index score was prognostic for greater risk of relapse and mortality but not NRM. QOL assessments, particularly physical functioning and functional well-being, may provide independent prognostic information beyond standard clinical measures in allogeneic HCT recipients.


Assuntos
Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Qualidade de Vida , Adolescente , Adulto , Idoso , Aloenxertos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida
6.
Leukemia ; 28(7): 1486-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24406841

RESUMO

Pulmonary hypertension (PH) is a frequently under recognized complication of myelofibrosis (MF). The pathophysiology of PH in MF is unknown and no definitive therapies have been established. We studied 15 patients with MF-associated PH and compared their echocardiographic and PH relevant biomarkers (nitric oxide (NO), N-terminal pro-hormone of brain natriuretic peptide (NT-pro BNP), von Willebrand antigen (vWB), ristocetin-cofactor activity (RCA) and uric acid (UA)) pre- and post-ruxolitinib treatment. Ruxolitinib decreased the plasma levels of NT-pro BNP (73%; P=0.043), UA (60%), vWB (86%) and RCA (73%; P=0.036). Improvements in echocardiographic findings were also seen in 66% of patients (P=0.022). Furthermore, marked increase in NO compared with baseline (69.75 vs 40.1 picomolar (pM); P=0.001) was observed post-ruxolitinib therapy, whereas no changes were noted with conventional therapies. Treatment with ruxolitinib also resulted in the reduction of key cytokines (tumor necrosis factor alpha, interleukin-4 (IL-4), IL-6 and IL-8) and induction of interferon-gamma. Animal studies further supported the role of ruxolitinib in the induction of NO levels. In conclusion, aberrant Janus kinase (JAK)-signal transducer and activator of transcription signaling in MF may mediate PH through dysregulation of NO and cytokine levels, which can be restored by therapy with JAK inhibitors suggesting that inhibition of this pathway is a novel target for the management of patients with PH.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Mielofibrose Primária/complicações , Pirazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/sangue , Citocinas/sangue , Modelos Animais de Doenças , Ecocardiografia , Feminino , Ferritinas/sangue , Humanos , Hipertensão Pulmonar/diagnóstico , Janus Quinases/antagonistas & inibidores , Masculino , Camundongos Knockout , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Nitrilas , Mielofibrose Primária/sangue , Mielofibrose Primária/genética , Pirimidinas
7.
Leukemia ; 26(5): 1091-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22042147

RESUMO

There are limited data on hematopoietic cell transplantation (HCT) in primary plasma cell leukemia (pPCL), an aggressive plasma cell disorder. We report outcomes of 147 patients with pPCL receiving autologous (n=97) or allogeneic (n=50) HCT within 18 months after diagnosis between 1995 and 2006. Median age was 56 years and 48 years for autologous HCT and allogeneic HCT, respectively. Progression-free survival (PFS) at 3 years was 34% (95% confidence interval (CI), 23-46%) in the autologous group and 20% (95% CI, 10-34%) in the allogeneic group. Cumulative incidence of relapse at 3 years was 61% (95% CI, 48-72%) in the autologous group and 38% (95% CI, 25-53%) in the allogeneic group. Overall survival (OS) at 3 years was 64% (95% CI, 52-75%) in the autologous group and 39% (95% CI, 26-54%) in the allogeneic group. Non-relapse mortality (NRM) at 3 years was 5% (95% CI, 1-11%) in the autologous group and 41% (95% CI, 28-56%) in the allogeneic group. The encouraging OS after autologous HCT, establishes the safety and feasibility of this consolidative treatment option after initial induction therapy for pPCL. Allogeneic HCT, although associated with a significantly lower relapse rate, carries a much higher risk of NRM and no OS benefit.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Plasmocitária/cirurgia , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Br J Cancer ; 104(6): 957-67, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21364585

RESUMO

BACKGROUND: Although inhibitors of histone deacetylase inhibitors (HDACis) in combination with genotoxins potentiate apoptosis, the role of proteases other than caspases in this process remained elusive. Therefore, we examined the potentiation of apoptosis and related mechanisms of HDACis and doxorubicin combination in a panel of myeloma cell lines and in 25 primary myelomas. RESULTS: At IC(50) concentrations, sodium butyrate (an HDACi) or doxorubicin alone caused little apoptosis. However, their combination potentiated apoptosis and synergistically reduced the viability of myeloma cells independent of p53 and caspase 3-7 activation. Potentiated apoptosis correlated with nuclear translocation of apoptosis-inducing factor, suggesting the induction of caspase 3- and 7-independent pathways. Consistent with this, butyrate and doxorubicin combination significantly increased the activity of cytoplasmic cathepsin B. Inhibition of cathepsin B either with a small-molecule inhibitor or downregulation with a siRNA reversed butyrate- and doxorubicin-potentiated apoptosis. Finally, ex vivo, clinically relevant concentrations of butyrate or SAHA (suberoylanilide hydroxamic acid, vorinostat, an HDACi in clinical testing) in combination with doxorubicin significantly (P<0.0001) reduced the survival of primary myeloma cells. CONCLUSIONS: Cathepsin B has a prominent function in mediating apoptosis potentiated by HDACi and doxorubicin combinations in myeloma. Our results support a molecular model of lysosomal-mitochondrial crosstalk in HDACi- and doxorubicin-potentiated apoptosis through the activation of cathepsin B.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Catepsina B/fisiologia , Doxorrubicina/administração & dosagem , Inibidores de Histona Desacetilases/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Caspases/metabolismo , Caspases/fisiologia , Catepsina B/antagonistas & inibidores , Catepsina B/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citoplasma/metabolismo , Doxorrubicina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Sinergismo Farmacológico , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/farmacologia , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , RNA Interferente Pequeno/farmacologia , Vorinostat
9.
Bone Marrow Transplant ; 30(5): 311-4, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12209353

RESUMO

High-dose etoposide (2 g/m(2)) plus G-CSF is a very effective regimen for peripheral blood progenitor cell (PBPC) mobilization. Unfortunately, neutropenia is common. The infectious complications associated with high-dose etoposide have not been previously described. After noting a high incidence of hospitalizations for neutropenic fever, we began a vigorous prophylactic antibiotic regimen for patients receiving high-dose etoposide plus G-CSF, attempting to reduce infectious complications. Ninety-eight patients underwent etoposide mobilization between December 1997 and June 2000. Three chronological patient groups received: (1) no specific antibiotic prophylaxis (n = 44); (2) vancomycin i.v., cefepime i.v., clarithromycin p.o., and ciprofloxacin p.o. (n = 27); and (3) vancomycin i.v., clarithromycin p.o., and ciprofloxacin p.o. (n = 27). The patients not receiving antibiotic prophylaxis had a 68% incidence of hospitalization for neutropenic fever. In the patients receiving prophylaxis, the incidence was reduced to 26% and 15% respectively, for an overall incidence of 20% (P < 0.001 for comparison between prophylaxed and unprophylaxed groups). We conclude that etoposide mobilization is associated with a significant incidence of neutropenic fever, which can be substantially reduced by a vigorous antimicrobial prophylactic program.


Assuntos
Antibioticoprofilaxia/métodos , Quimioterapia Combinada/uso terapêutico , Etoposídeo/efeitos adversos , Febre/prevenção & controle , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Neutropenia/prevenção & controle , Assistência Ambulatorial , Cefepima , Cefalosporinas/efeitos adversos , Ciprofloxacina/administração & dosagem , Claritromicina/administração & dosagem , Coleta de Dados , Etoposídeo/administração & dosagem , Feminino , Febre/induzido quimicamente , Mobilização de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Infecções Oportunistas/prevenção & controle , Vancomicina/administração & dosagem
10.
Cleve Clin J Med ; 68(11): 913, 917, 920-1, 925-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11718431

RESUMO

Chronic myelogenous leukemia (CML) can usually be cured by bone marrow transplantation from matched donors. Donor T-cell activity from the graft is critical to maintaining remission. Myeloablation may not be necessary for cure. Non-myeloablative but immunosuppressive preparative regimens allow donor engraftment with less toxicity. Early combination therapy with interferon-alfa and cytarabine was the preferred option for patients who could not undergo bone marrow transplantation. Now, the advent of imatinib mesylate, a specific inhibitor of BCR/ABL tyrosine kinase, promises to change existing treatment paradigms


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Efeito Enxerto vs Leucemia , Interferon-alfa/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Benzamidas , Ensaios Clínicos como Assunto , Diagnóstico Diferencial , Inibidores Enzimáticos/uso terapêutico , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Guias de Prática Clínica como Assunto , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Proteínas Tirosina Quinases/antagonistas & inibidores , Indução de Remissão
11.
Bone Marrow Transplant ; 28(5): 491-5, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11593323

RESUMO

Nonmyeloablative peripheral blood stem cell transplantation (PBSCT) is a novel therapeutic strategy for patients with malignant and non-malignant hematologic diseases. Infectious complications of this procedure have not been previously well described. Data on 12 patients transplanted at a tertiary care center were collected prospectively and verified retrospectively. Neutropenia developed in a third of patients, lasting for a median of 5 days. All patients developed some degree of graft-versus-host disease, as intended. Most patients achieved full chimerism by week 5. Bacterial infections occurred in two patients (17%). Cytomegalovirus (CMV) viremia occurred in five patients (42%) at a median of 80 days; none had received CMV prophylaxis. Viremia was associated with fever and fatigue in three patients, possible gastrointestinal involvement in one patient and was asymptomatic in one patient. All viremic patients responded to intravenous ganciclovir therapy. No fungal infections were documented. No patients died as a result of infection. The incidence of CMV viremia in our patients was high, but the incidence of invasive disease due to CMV was low. The best strategy to prevent CMV in patients undergoing nonmyeloablative PBSCT remains to be determined, but strategies employed in traditional allogeneic bone marrow transplantation should be considered in these patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Agonistas Mieloablativos/uso terapêutico , Condicionamento Pré-Transplante/efeitos adversos , Adulto , Infecções Bacterianas/etiologia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/etiologia , Feminino , Doença Enxerto-Hospedeiro/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/efeitos adversos , Estudos Prospectivos , Estudos Retrospectivos , Quimeras de Transplante , Transplante Homólogo , Resultado do Tratamento
12.
Leuk Res ; 24(7): 567-74, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10867130

RESUMO

Older patients with acute myelogenous leukemia (AML) have overexpression of P-glycoprotein (Pgp+), and this has been shown to correlate quantitatively with therapeutic outcome. Since Pgp-mediated efflux of cytotoxic drugs can be inhibited by the cyclosporine analogue, PSC 833, we investigated the use of this agent with a 5-day mitoxantrone/etoposide regimen in patients over age 55 with newly diagnosed AML. Previous studies suggested a 33% incidence of grade IV/V non-hematologic toxicity with the use of mitoxantrone 10 mg/M(2) and etoposide 100 mg/M(2), each for 5 days, in this patient population. Since PSC 833 alters the pharmacokinetic excretion of MDR-related cytotoxins, this phase I dose-finding study was performed to identify doses of mitoxantrone/etoposide associated with a similar 33% incidence of grade IV/V non-hematologic toxicity, when given with PSC 833. Mitoxantrone/etoposide (M/E) doses were escalated in fixed ratio from a starting dose of M: 4 mg/M(2) and E: 40 mg/M(2), to M: 7 mg/M(2) and E: 70 mg/M(2), in successive cohorts of eight patients each. PSC 833 was well tolerated and the MTD of this M/E regimen with PSC 833 in this population was M: 6 mg/M(2) and E: 60 mg/M(2). The complete response (CR) rate for all patients was 50% (15/30) and was considerably higher for de novo than for secondary AML. These data suggest that the addition of PSC 833 to an M/E regimen for older patients with untreated AML is well tolerated but requires a reduction in M/E dosing to avoid increased toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Ciclosporinas/administração & dosagem , Ciclosporinas/farmacocinética , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Etoposídeo/farmacocinética , Feminino , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/mortalidade , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/farmacocinética , Análise de Sobrevida , Resultado do Tratamento
13.
Blood ; 92(11): 4336-43, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9834240

RESUMO

We report an RNA targeting strategy, which selectively degrades bcr/abl mRNA in chronic myelogenous leukemia (CML) cells. A 2', 5'-tetraadenylate activator (2-5A) of RNase L was chemically linked to oligonucleotide antisense directed against either the fusion site or against the translation start sequence in bcr/abl mRNA. Selective degradation of the targeted RNA sequences was demonstrated in assays with purified RNase L and decreases of p210(bcr/abl) kinase activity levels were obtained in the CML cell line, K562. Furthermore, the 2-5A-antisense chimeras suppressed growth of K562, while having substantially reduced effects on the promyelocytic leukemia cell line, HL60. Findings were extended to primary CML cells isolated from bone marrow of patients. The 2-5A-antisense treatments both suppressed proliferation of the leukemia cells and selectively depleted levels of bcr/abl mRNA without affecting levels of beta-actin mRNA, determined by reverse transcriptase-polymerase chain reaction (RT-PCR). The specificity of this approach was further shown with control oligonucleotides, such as chimeras containing an inactive dimeric form of 2-5A, antisense lacking 2-5A, or chimeras with altered sequences including several mismatched nucleotides. The control oligonucleotides had either reduced or no effect on CML cell growth and bcr/abl mRNA levels. These findings show that CML cell growth can be selectively suppressed by targeting bcr/abl mRNA with 2-5A-antisense for decay by RNase L and suggest that these compounds should be further explored for their potential as ex vivo purging agents of autologous hematopoietic stem cell transplants from CML patients.


Assuntos
Endorribonucleases/genética , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/genética , Regulação Neoplásica da Expressão Gênica , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , RNA Mensageiro/antagonistas & inibidores , Proteínas Recombinantes de Fusão/genética , Nucleotídeos de Adenina/genética , Nucleotídeos de Adenina/farmacologia , Nucleotídeos de Adenina/uso terapêutico , Endorribonucleases/farmacologia , Ativação Enzimática/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/farmacologia , Oligorribonucleotídeos/uso terapêutico , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA