Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 575
Filtrar
1.
Extremophiles ; 21(4): 775-788, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28500387

RESUMEN

Thermus filiformis is an aerobic thermophilic bacterium isolated from a hot spring in New Zealand. The experimental study of the mechanisms of thermal adaptation is important to unveil response strategies of the microorganism to stress. In this study, the main pathways involved on T. filiformis thermoadaptation, as well as, thermozymes with potential biotechnological applications were revealed based on omics approaches. The strategy adopted in this study disclosed that pathways related to the carbohydrate metabolism were affected in response to thermoadaptation. High temperatures triggered oxidative stress, leading to repression of genes involved in glycolysis and the tricarboxylic acid cycle. During heat stress, the glucose metabolism occurred predominantly via the pentose phosphate pathway instead of the glycolysis pathway. Other processes, such as protein degradation, stringent response, and duplication of aminoacyl-tRNA synthetases, were also related to T. filiformis thermoadaptation. The heat-shock response influenced the carotenoid profile of T. filiformis, favoring the synthesis of thermozeaxanthins and thermobiszeaxanthins, which are related to membrane stabilization at high temperatures. Furthermore, antioxidant enzymes correlated with free radical scavenging, including superoxide dismutase, catalase and peroxidase, and metabolites, such as oxaloacetate and α-ketoglutarate, were accumulated at 77 °C.


Asunto(s)
Adaptación Fisiológica , Extremófilos/fisiología , Thermus/fisiología , Calor , Espectrometría de Masas , Metabolómica , Proteómica , Transcriptoma
2.
Ann Hematol ; 95(2): 211-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26546359

RESUMEN

The primary objective of this study was to investigate whether the presence of comorbidities was associated with a lower health-related quality of life (HRQOL) in elderly patients with chronic myeloid leukemia (CML). A sample of 174 CML patients aged 60 years or above was analyzed. HRQOL was assessed with the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). A number of pre-selected sociodemographic and disease-related factors were considered as potential confounding factors for the association between comorbidity and HRQOL. Mean age of the 174 patients analyzed was 70 years (range 60-87 years) and 55 % were male. Overall, 111 patients (64 %) reported at least one comorbidity. Analysis stratified by age group category showed a greater proportion of patients with comorbidities in the older sub-group population (≥70 years) compared to younger patients (60 to 69 years). Differences in HRQOL outcomes between patients with no comorbidity at all and those with two or more comorbid conditions were at least twice the magnitude of a clinically meaningful difference in all the physical and mental health scales of the SF-36. In multivariate analysis, after adjusting for key confounding factors, the following scales were significantly lower in those with comorbidity: general health (p < 0.001), bodily pain (p < 0.001), physical functioning (p = 0.002), and vitality (p = 0.002). Assessing comorbidity in elderly patients with CML is important to facilitate identification of those most in need of HRQOL improvements.


Asunto(s)
Estado de Salud , Encuestas Epidemiológicas , Leucemia Mielógena Crónica BCR-ABL Positiva/epidemiología , Leucemia Mielógena Crónica BCR-ABL Positiva/psicología , Calidad de Vida/psicología , Anciano , Anciano de 80 o más Años , Comorbilidad , Estudios Transversales , Femenino , Encuestas Epidemiológicas/métodos , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/psicología , Dolor/epidemiología , Dolor/psicología
3.
Ann Oncol ; 25(2): 447-54, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24478321

RESUMEN

BACKGROUND: The main objective of this study was to assess preferences for involvement in treatment decisions and requests for prognostic information in newly diagnosed higher-risk myelodysplastic syndrome (MDS) patients. PATIENT AND METHODS: This was a prospective cohort observational study that consecutively enrolled MDS patients with an international prognostic scoring system (IPSS) risk category of intermediate-2 or high risk (summarized as 'higher risk'). The control preference scale was used to assess patient preferences for involvement in treatment decisions, and whether a request by patients for prognostic information during consultation was made, was also recorded. All of the patients were surveyed at the time of diagnosis before receiving treatment. Univariate and multivariate analyses were carried out to assess how sociodemographic, clinical and laboratory data related to decision-making preferences and requests for prognostic information. Relationship with the health-related quality of life (HRQOL) profile was also examined. RESULTS: A total of 280 patients were enrolled, 74% with intermediate-2 and 26% with high-risk IPSS. The mean age of patients was 70-year old (range: 32-89 years). One hundred thirty-two patients (47%) favored a passive role in treatment decision-making, whereas only 14% favored an active role. The remaining 39% of patients favored a shared decision-making approach. Patients with lower hemoglobin levels were more likely to prefer a passive role (P=0.037). HRQOL was generally better in patients preferring an active role versus those preferring a passive one. Overall, 61% (N=171) of patients requested prognostic information on survival during consultation. The likelihood of not requesting prognostic information was higher for older patients (P = 0.003) and for those with lower education (P=0.010). CONCLUSION: Decision-making preferences vary among patients with newly diagnosed higher-risk MDS. Current findings suggest that patients with worse underlying health conditions are more likely to prefer less involvement in treatment decisions.


Asunto(s)
Síndromes Mielodisplásicos/diagnóstico , Participación del Paciente/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Toma de Decisiones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/epidemiología , Síndromes Mielodisplásicos/terapia , Prioridad del Paciente , Prevalencia , Pronóstico , Estudios Prospectivos , Factores Socioeconómicos , Resultado del Tratamiento
4.
Lett Appl Microbiol ; 57(1): 40-6, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23530753

RESUMEN

UNLABELLED: The superoxide dismutase (TfSOD) gene from the extremely thermophilic bacterium Thermus filiformis was cloned and expressed at high levels in mesophilic host. The purified enzyme displayed approximately 25 kDa band in the SDS-PAGE, which was further confirmed as TfSOD by mass spectrometry. The TfSOD was characterized as a cambialistic enzyme once it had enzymatic activity with either manganese or iron as cofactor. TfSOD showed thermostability at 65, 70 and 80°C. The amount of enzyme required to inhibit 50% of pyrogallol autoxidation was 0·41, 0·56 and 13·73 mg at 65, 70 and 80°C, respectively. According to the circular dichroism (CD) spectra data, the secondary structure was progressively lost after increasing the temperature above 70°C. The 3-dimensional model of TfSOD with the predicted cofactor binding corroborated with functional and CD analysis. SIGNIFICANCE AND IMPACT OF THE STUDY: This manuscript describes the expression and characterization of a superoxide dismutase (SOD) from Thermus filiformis with thermophilic and cambialistic characteristics. The SODs are among the most potent antioxidants known in nature, and their stability and pharmacokinetics can vary widely in accordance to their biological source. Although the currently clinical research work has been focused on human and bovine SODs, alternative sources may become more biotechnological attractive in the near future. Our study brings new insights for the research field of antioxidant enzymes with potential application on pharmaceutical, cosmetics and food formulations.


Asunto(s)
Superóxido Dismutasa/química , Superóxido Dismutasa/genética , Thermus/enzimología , Thermus/genética , Dicroismo Circular , Clonación Molecular , Coenzimas/metabolismo , Estabilidad de Enzimas , Hierro/metabolismo , Manganeso/metabolismo , Modelos Moleculares , Desnaturalización Proteica , Estructura Secundaria de Proteína , Superóxido Dismutasa/metabolismo , Temperatura , Thermus/metabolismo
5.
Br J Cancer ; 107(6): 904-9, 2012 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-22871884

RESUMEN

BACKGROUND: Optimal adherence to imatinib therapy is of paramount importance to maximise treatment effectiveness in patients with chronic myeloid leukaemia (CML). The main objective of this study was to investigate patient-reported personal factors associated with adherence behaviour. METHODS: Analysis was conducted on 413 CML patients receiving long-term therapy with imatinib. Adherence behaviour was measured with the Morisky Medication Adherence Scale and personal factors investigated included: quality of life, perceived social support, fatigue, symptom burden, psychological wellbeing and desire for additional information. Key socio-demographic and treatment-related factors were also taken into account. Univariate and multivariate logistic regression analyses were used to investigate factors associated with optimal adherence to therapy. RESULTS: In all, 53% of patients reported an optimal adherence behaviour. The final multivariate model retained the following variables as independent predictors of optimal adherence to therapy: desire for more information (ref. no), odds ratio (OR)=0.43 (95% confidence interval (CI), 0.29-0.66; P<0.001), social support (higher score representing greater support), OR=1.29 (95% CI, 1.11-1.49; P<0.001) and concomitant drug burden (ref. no), OR=1.82 (95% CI, 1.18-2.80; P=0.006). CONCLUSION: This study suggests that a higher level of social support, satisfaction with information received and concomitant drug burden are the main factors associated with greater adherence to long-term imatinib therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Fatiga , Conducta en la Búsqueda de Información , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Cumplimiento de la Medicación , Piperazinas/administración & dosificación , Pirimidinas/administración & dosificación , Calidad de Vida , Apoyo Social , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Antineoplásicos/efectos adversos , Benzamidas , Fatiga/etiología , Fatiga/psicología , Femenino , Humanos , Mesilato de Imatinib , Modelos Logísticos , Masculino , Cumplimiento de la Medicación/psicología , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Oportunidad Relativa , Piperazinas/efectos adversos , Pirimidinas/efectos adversos , Factores de Riesgo , Resultado del Tratamiento
6.
Leukemia ; 21(1): 79-83, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16932337

RESUMEN

Although the occurrence of thrombosis in acute promyelocytic leukemia (APL) has been reported during retinoic acid treatment, no studies carried out in large clinical cohorts have specifically addressed this issue. We analyzed 124 APL patients treated with the all-trans retinoic acid and idarubicin protocol and compared clinico-biologic characteristics of 11 patients who developed thrombosis with those of 113 patients who had no thrombosis. In seven patients, the events were recorded during induction, whereas in four patients deep vein thrombosis occurred in the post-induction phase. Comparison of clinico-biological characteristics of patients with and without thrombosis revealed in the former group higher median white blood cell (WBC) count (17 x 10(9)/l, range 1.2-56, P=0.002), prevalence of the bcr3 transcript type (72 vs 48%, P=0.01), of FLT3-ITD (64 vs 28%, P=0.02), CD2 (P=0.0001) and CD15 (P=0.01) expression. No correlation was found with sex, age, French-American-British subtype, all-trans-retinoic acid syndrome or with thrombophilic state that was investigated in 5/11 patients. Our findings suggest that, in APL patients consistent biologic features of leukemia cells may predict increased risk of developing thrombosis.


Asunto(s)
Antineoplásicos/efectos adversos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Trombosis/inducido químicamente , Tretinoina/efectos adversos , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Antineoplásicos/administración & dosificación , Antígenos CD2 , Femenino , Humanos , Idarrubicina/administración & dosificación , Idarrubicina/efectos adversos , Leucemia Promielocítica Aguda/sangre , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/inmunología , Recuento de Leucocitos , Antígeno Lewis X , Masculino , Persona de Mediana Edad , Mutación , Valor Predictivo de las Pruebas , Factores de Riesgo , Secuencias Repetidas en Tándem/genética , Trombosis/genética , Trombosis/inmunología , Tretinoina/administración & dosificación , Tirosina Quinasa 3 Similar a fms/genética
8.
Leukemia ; 20(10): 1723-30, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16932345

RESUMEN

In this trial, acute myeloid leukemia patients (pts) aged 61-80 years received MICE (mitoxantrone, etoposide and cytarabine) induction chemotherapy in combination with different schedules of granulocyte colony-stimulating factor administration. Pts in complete remission were subsequently randomized for two cycles of consolidation therapy: mini-ICE regimen (idarubicin, etoposide and cytarabine) given according to either an intravenous (i.v.) or a 'non-infusional' schedule. Among the 346 pts randomized for the second step, 331 pts received consolidation-1 and 182 consolidation-2. A total of 290 events (255 relapses, 35 deaths in first CR) have been reported. The median follow-up was 4.4 years. No significant differences were detected in terms of disease-free survival (median 9 vs 10.4 months, P=0.15, hazard ratio (HR) =1.18, 95% confidence interval (CI) 0.94-1.49) - primary end point - and survival (median 15.7 vs 17.8 months, P=0.19, HR=1.17, 95% CI 0.92-1.50). In the 'non-infusional' arm grade 3-4 vomiting (10 vs 2%; P=0.001) and diarrhea (10 vs 4%; P=0.03) were higher than in the 'i.v.' arm, whereas time to platelet recovery >20 x 10(9)/l (median: 19 vs 23 days; P=0.02) and duration of hospitalization (mean: 15 vs 27 days; P<0.0001) was shorter. The 'non-infusional' consolidation regimen resulted in an antileukemic effect similar to the intravenous regimen, which was less myelosuppressive and associated with less hospitalization days.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Leucemia Mieloide/tratamiento farmacológico , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Citarabina/administración & dosificación , Supervivencia sin Enfermedad , Etopósido/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Idarrubicina/administración & dosificación , Infusiones Intravenosas , Tiempo de Internación , Masculino , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Pancitopenia , Cooperación del Paciente , Factores de Riesgo
9.
Leukemia ; 19(4): 628-35, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15744351

RESUMEN

Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) has a dismal prognosis. We prospectively evaluated minimal residual disease (MRD) by measuring BCR/ ABL levels with a quantitative real-time PCR procedure after induction and after consolidation in 45 adults with Ph+ ALL who obtained complete hematological remission after a high-dose daunorubicin induction schedule. At diagnosis, the mean BCR-ABL/GUS ratio was 1.55 +/- 1.78. A total of 42 patients evaluable for outcome analysis were operationally divided into two MRD groups: good molecular responders (GMRs; n = 28) with > 2 log reduction of residual disease after induction and > 3 log reduction after consolidation therapy, and poor molecular responders (PMRs; n = 14) who, despite complete hematological remission, had a higher MRD at both time points. In GMR, the actuarial probability of relapse-free, disease-free and overall survival at two years was 38, 27 and 48%, respectively, as compared to 0, 0 and 0% in PMR (P = 0.0035, 0.0076 and 0.0026, respectively). Salvage therapy induced a second sustained complete hematological remission in three GMR patients, but in no PMR patient. Our data indicate that, as already shown in children, adult Ph+ ALL patients have a heterogeneous sensitivity to treatment, and that early quantification of residual disease is a prognostic parameter in this disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Proteínas de Fusión bcr-abl/genética , Cromosoma Filadelfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Antibióticos Antineoplásicos/uso terapéutico , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Asparaginasa/uso terapéutico , Citarabina/uso terapéutico , Daunorrubicina/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/genética , Neoplasia Residual/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Valor Predictivo de las Pruebas , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vincristina/uso terapéutico
10.
Leukemia ; 19(10): 1768-73, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16079891

RESUMEN

The therapeutic activity and toxicity profile of gemtuzumab ozogamicin were assessed in 40 patients >60 years of age with acute myeloid leukemia (AML) who were not considered eligible for conventional chemotherapy because of advanced age or poor performance status. The drug was administered at the dose of 9 mg/m2 as a single 2-h i.v. infusion on days 1 and 15. Patients who achieved a complete remission (CR/CRp) were to receive a consolidation with two additional injections of the immunotoxin at the same dose. The overall CR/CRp rate was 17% (95% CI, 8-32%). The CR/CRp rate in patients 61-75 years old was 33% (6/18), and 5% (1/22) in patients older than 75 years. Induction death occurred in seven patients (17%), all aged above 75 years. Overall survival was significantly longer in patients aged 61-75 years than in older individuals (P=0.05), and in CD33+ cases than in CD33- cases (P=0.05). We conclude that the dose/schedule of gemtuzumab ozogamicin used in this trial is too toxic in the age group over 75 years. For these patients, additional studies with reduced doses of the immunotoxin are warranted.


Asunto(s)
Aminoglicósidos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Anciano Frágil , Inmunotoxinas/uso terapéutico , Leucemia Mieloide/tratamiento farmacológico , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados , Femenino , Gemtuzumab , Humanos , Leucemia Mieloide/clasificación , Masculino , Persona de Mediana Edad , Inducción de Remisión , Tasa de Supervivencia
11.
Cancer Res ; 55(8): 1625-8, 1995 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-7712464

RESUMEN

We have analyzed by Southern blotting the ALL-1 (MLL, HRX, Hrtx 1) gene configuration in a series of 126 patients with acute myeloid leukemia (AML) representative of all ages and French-American-British Classification groups and correlated this genetic feature with clinical and biological features at diagnosis. ALL-1 gene rearrangements were detected in 17 of the 74 cases with M4-M5 (myelomonocytic and monocytic) AML and in 2 of the 52 cases with other leukemic subtypes (P < 0.01). Within the series of 74 M4-M5 patients, ALL-1 rearrangements were significantly associated with French-American-British Classification M5 (P = 0.009), high WBC (P = 0.002), and young age. In particular, all 5 infant (< 1.5 years) AML cases, 6 of the 19 (31%) patients between 1.5 and 18 years of age, and 6 of the 50 (12%) patients > 18 years old showed an altered ALL-1 genomic configuration (P < 0.001). Immunophenotypic characterization revealed coexpression of lymphoid and myeloid markers in 6 of 17 ALL-1 rearranged M4-M5 cases. The IgH gene configuration was studied in 77 of 126 AMLs. Five patients (6%) showed IgH clonal rearrangements and all were in the ALL-1 rearranged group (P < 0.0001). Our findings indicate that ALL-1 rearrangement is the commonest genetic alteration presently detectable in M4-M5 AML, particularly in childhood where it is found in up to one-third of all cases. The association of IgH rearrangements with ALL-1 alterations in AML, coupled to the frequent detection in this subset of lymphoid associated markers, further supports the origin of these tumors from a common multipotent precursor with bipotential lymphoid and monocytic differentiation capability.


Asunto(s)
Proteínas de Unión al ADN/genética , Reordenamiento Génico , Leucemia Monocítica Aguda/genética , Leucemia Mielomonocítica Aguda/genética , Proto-Oncogenes , Factores de Transcripción , Adolescente , Adulto , Factores de Edad , Anciano , Niño , Preescolar , Femenino , Francia , N-Metiltransferasa de Histona-Lisina , Humanos , Inmunofenotipificación , Lactante , Recién Nacido , Leucemia Monocítica Aguda/clasificación , Leucemia Monocítica Aguda/inmunología , Leucemia Mielomonocítica Aguda/clasificación , Leucemia Mielomonocítica Aguda/inmunología , Masculino , Persona de Mediana Edad , Proteína de la Leucemia Mieloide-Linfoide , Mapeo Restrictivo , Reino Unido , Estados Unidos , Dedos de Zinc
12.
Cancer Res ; 51(3): 964-8, 1991 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1988139

RESUMEN

The effect of treatment with interleukin 2 (IL2) on the phenotypic and functional immune system of acute leukemia patients was investigated. Fifteen acute myeloid leukemia and acute lymphoid leukemia patients with evidence of persistent disease were further subdivided into two groups according to the percentage of bone marrow (BM) blasts: group a had 6-15% blasts and group b had 30-65%. Following two cycles of IL2 (Glaxo Imb, Geneva, Switzerland) given i.v. by continuous infusion at escalating doses, no major changes in the proportion of CD3-, CD4-, and CD8-positive cells were encountered in the blood or in the marrow of either group of patients. When these could be retested after four cycles of IL2, a significant increase of CD3+ and CD4+ cells was documented in the peripheral blood (PB), as well as a significant increase of CD3+ cells in the BM. Irrespective of the number of cycles administered, the proportion of CD16+ cells increased significantly in the blood in both groups of patients and in the marrow of group a patients only. The expression of CD25 was significantly enhanced in all samples tested. Following IL2 administration, an enhancement of the natural killer compartment was documented. This was consistently more evident in patients with more limited disease. A significant amplification of the in vitro-induced lymphokine-activated killer function was noted in the BM of the treated patients. Furthermore, we documented the presence both in the PB and in the BM of "spontaneous" lymphokine-activated killer cells generated in vivo following IL2 administration. These results demonstrate that in acute leukemia of both myeloid and lymphoid origin, treatment with IL2 is capable of inducing profound immunophenotypic and functional modifications in PB and in BM lymphocytes, particularly in patients with more limited disease. The evidence of the in vivo activation of cytotoxic cells, particularly in the BM, may help to explain the clinical responses preliminarily observed in individual acute leukemia patients.


Asunto(s)
Inmunofenotipificación , Interleucina-2/uso terapéutico , Células Asesinas Activadas por Linfocinas , Células Asesinas Naturales , Leucemia Mieloide/inmunología , Leucemia Mieloide/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Enfermedad Aguda , Adolescente , Adulto , Niño , Femenino , Humanos , Células Asesinas Activadas por Linfocinas/efectos de los fármacos , Células Asesinas Naturales/efectos de los fármacos , Leucemia Mieloide/sangre , Masculino , Persona de Mediana Edad , Fenotipo , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre
13.
Cancer Res ; 53(16): 3800-3, 1993 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8339294

RESUMEN

The chromosome 11q23 band is a genetic region frequently involved in nonrandom karyotypic abnormalities of acute leukemia. A genomic locus named ALL-1 or MLL, where 11q23 breakpoints are clustered, has been recently cloned and characterized. We have made use of an ALL-1-specific probe in Southern blot experiments to analyze the configuration of this gene in a large series of acute leukemia patients, representative of all different myeloid and lymphoid subtypes. Nine of 145 cases (6.2%) showed abnormal ALL-1 restriction fragments in leukemic DNAs. Of these nine cases, five patients in whom karyotypic data were available displayed chromosome 11q23 aberrations, including t(4;11) (three cases) and t(9;11) (two cases). Immunophenotypic and morphocytochemical characterization of ALL-1-rearranged acute leukemia revealed prevalence of poorly differentiated B lymphoid and/or monoblastic features. Considering the whole series, ALL-1 rearrangements were significantly associated with female sex, higher white blood cell counts at presentation, and very poor clinical outcome. The presence of residual disease was molecularly documented in one case at the time of clinical remission after induction treatment and was followed by early relapse. We conclude that ALL-1 rearrangements are new molecular markers of human leukemia with considerable diagnostic and prognostic relevance.


Asunto(s)
Cromosomas Humanos Par 11 , Reordenamiento Génico , Leucemia/genética , Enfermedad Aguda , Adolescente , Adulto , Anciano , Southern Blotting , Niño , Preescolar , Femenino , Humanos , Lactante , Cariotipificación , Leucemia/patología , Masculino , Persona de Mediana Edad
14.
Cancer Res ; 57(14): 2879-83, 1997 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9230194

RESUMEN

The ALL1 gene (also called MLL, HRX, or Htrx1) at the cytogenetic band 11q23 is consistently altered by chromosome rearrangements in acute leukemias (ALs) of early infancy, in ALs developed after exposure to topoisomerase (topo) II-inhibitory drugs, and in a small subset of de novo ALs in children and adults. Because exposure to natural or medicinal substances blocking topo II during pregnancy have been proposed as etiological agents for infant leukemia, we have compared the distribution of ALL1 gene breakpoints in infant leukemias with an altered ALL1 gene configuration to those in secondary leukemia associated with prior exposure to topo II targeting drugs and in reference to the major topo consensus binding site in exon 9. ALL1 gene breakpoint distribution was determined by Southern blot hybridization and/or reverse transcription-PCR of the ALL1/AF4 fusion cDNA in 70 patients. Using restriction enzyme analysis, the 8.3-kb ALL1 breakpoint cluster region was divided in a centromeric portion of 3.5 kb (region A) and telomeric portion of a 4.8 kb (region B). ALL1 breakpoint were located in region A in 8 of 28 (28.5%) cases of infant ALs, 16 of 24 (66%) cases of de novo ALs, and 0 of 5 cases of therapy-related (TR) ALs. Conversely, ALL1 breakpoints in region B were detected in 20 of 28 (71.5%) cases of infant AL, 8 of 24 (33%) cases of de novo AL, and 5 of 5 (100%) cases of TR AL (P = 0.002). These results were confirmed by direct sequencing of the ALL1/AF4 fusion transcript in 30 cases (19 infants and 11 child and adult de novo cases). The analysis of ALL1/AF4 junction types showed that children and adults with de novo leukemia had ALL1 breakpoints in intron 6 (9 cases) or intron 7 (2 cases), whereas breakpoints in infant cases were mainly located in intron 8 (14 cases) and less frequently in intron 6 (4 cases) and intron 7 (1 case). The difference in ALL1 breakpoint location between infant and noninfant AL patients with ALL1/AF4 fusion was statistically significant (P = 0.00005). These data demonstrated that infant and TR ALs share a similar biased clustering of ALL1 gene breakpoints, which supports the possibility that topo II inhibitors may also operate in utero and play a crucial role in the etiology of infant leukemia.


Asunto(s)
Antineoplásicos/efectos adversos , Proteínas de Unión al ADN/genética , Inhibidores Enzimáticos/efectos adversos , Leucemia/genética , Neoplasias Primarias Secundarias/genética , Proto-Oncogenes , Inhibidores de Topoisomerasa II , Factores de Transcripción , Enfermedad Aguda , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Reordenamiento Génico , N-Metiltransferasa de Histona-Lisina , Humanos , Lactante , Masculino , Persona de Mediana Edad , Proteína de la Leucemia Mieloide-Linfoide
15.
Cancer Res ; 41(10): 3979-84, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7285007

RESUMEN

Parallel determinations of glucocorticoid receptors in the cells of patients with various forms of leukemia were made by two assay methods, one using cell-free cytosolic extracts and the other using whole-cell preparations. Both assays revealed saturable binding of triamcinolone acetonide in all cases. The mean equilibrium dissociation constant for the interaction of triamcinolone acetonide with the cytoplasmic receptor at 2 degrees was 9.45 +/- 6.33 (S.D.) nM while that for the whole-cell binding at 37 degrees was 6.13 +/- 3.25 nM, suggesting an increase in receptor affinity at physiological temperatures. Competition experiments with various unlabeled steroids revealed a higher degree of glucocorticoid specificity at 37 degrees in whole-cell suspensions than at 2 degrees in cytosol. In a comparative analysis of 41 leukemic cell specimens, it was found that determinations carried out by whole-cell assay, calculated as number of sites per cell correlated well with those performed by cytosol assay, calculated as fmol/mg protein, independent of the type of leukemia. However, for cells with low receptor content, the two assay methods were more difficult to compare. In agreement with previous reports, the cytosol assay consistently underestimated the number of receptors with respect to the whole-cell assay, particularly in cases of lymphatic leukemia. Furthermore, the underestimation decreased for increasing levels of total cellular receptor. These results suggest that, in addition to possible defects in the cytoplasm-to-nucleus translocation process, the acceptor-binding capacity of the nucleus may also represent one of the factors which determines the levels of assayable cytoplasmic receptors. Moreover, they indicate that the two assay methods furnish nonequivalent information.


Asunto(s)
Leucemia/análisis , Receptores de Glucocorticoides/análisis , Receptores de Esteroides/análisis , Citosol/análisis , Humanos , Temperatura , Triamcinolona Acetonida/metabolismo
16.
Mol Biotechnol ; 58(11): 757-766, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27665110

RESUMEN

Enzymes isolated from extremophiles often exhibit superior performance and potential industrial applications. There are several advantages performing biocatalysis at elevated temperatures, including enhanced reaction rates, increased substrate solubility and decreased risks of contamination. Furthermore, thermophilic enzymes usually exhibit high resistance against many organic solvents and detergents, and are also more resistant to proteolytic attack. In this study, we subcloned and characterized an esterase from the hyperthermophilic archaeon Pyrococcus furiosus (Pf_Est) that exhibits optimal activity around 80 °C using naphthol-derived substrates and p-nitrophenyl palmitate (pNPP). According to the circular dichroism spectra, the secondary structure of P. furiosus esterase, which is predominantly formed by a ß-sheet structure, is very stable, even after incubation at 120°C. We performed SAXS to determine the low-resolution structure of Pf_Est, which is monomeric in solution at 80 °C and has a molecular weight of 28 kDa. The Km and V max values for this esterase acting on pNPP were 0.53 mmol/L and 6.5 × 10-3 U, respectively. Pf_Est was most active in the immiscible solvents and retained more than 50 % in miscible solvents. Moreover, Pf_Est possesses transesterification capacity, presenting better results when isobutanol was used as an acyl acceptor (2.69 ± 0.14 × 10-2 µmol/min mg) and the highest hydrolytic activity toward olive oil among different types of oils testes in this study. Collectively, these biophysical and catalytic properties are of interest for several biotechnological applications that require harsh conditions, including high temperature and the presence of organic solvents.


Asunto(s)
Clonación Molecular/métodos , Esterasas/química , Esterasas/metabolismo , Pyrococcus furiosus/enzimología , Proteínas Arqueales/química , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Biocatálisis , Dicroismo Circular , Estabilidad de Enzimas , Esterasas/genética , Calor , Modelos Moleculares , Peso Molecular , Naftoles/metabolismo , Estructura Secundaria de Proteína , Pyrococcus furiosus/genética , Dispersión del Ángulo Pequeño , Difracción de Rayos X
17.
Leukemia ; 30(10): 1987-1992, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27133819

RESUMEN

The APL0406 study showed that arsenic trioxide (ATO) and all-trans retinoic acid (ATRA) are not inferior to standard ATRA and chemotherapy (CHT) in newly diagnosed, low-intermediaterisk acute promyelocytic leukaemia (APL). We analysed the kinetics of promyelocytic leukaemia-retinoic acid receptor-α (PML-RARα) transcripts by real-time quantitative PCR (RQ-PCR) in bone marrow samples from 184 patients and assessed the prognostic impact of fms-related tyrosine kinase 3-internal tandem duplication (FLT3-ITD) in 159 patients enrolled in this trial in Italy. After induction therapy, the reduction of PML-RARα transcripts was significantly greater in patients receiving ATRA-CHT as compared with those treated with ATRA-ATO (3.4 vs 2.9 logs; P=0.0182). Conversely, at the end of consolidation, a greater log reduction of PML-RARα transcripts was detected in the ATRA-ATO as compared with the ATRA-CHT group (6.3 vs 5.3 logs; P=0.0024). FLT3-ITD mutations had no significant impact on either event-free survival (EFS) or cumulative incidence of relapse in patients receiving ATRA-ATO, whereas a trend for inferior EFS was observed in FLT3-ITD-positive patients receiving ATRA-CHT. Our study shows at the molecular level that ATRA-ATO exerts at least equal and probably superior antileukaemic efficacy compared with ATRA-CHT in low-intermediaterisk APL. The data also suggest that ATRA-ATO may abrogate the negative prognostic impact of FLT3-ITD.


Asunto(s)
Arsenicales/administración & dosificación , Leucemia Promielocítica Aguda/tratamiento farmacológico , Proteínas de Fusión Oncogénica/sangre , Óxidos/administración & dosificación , Tretinoina/administración & dosificación , Tirosina Quinasa 3 Similar a fms/genética , Adolescente , Adulto , Anciano , Trióxido de Arsénico , Arsenicales/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Humanos , Quimioterapia de Inducción/métodos , Italia , Cinética , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Óxidos/uso terapéutico , Pronóstico , Tretinoina/uso terapéutico , Adulto Joven
18.
J Clin Oncol ; 11(12): 2362-9, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7504091

RESUMEN

PURPOSE: To evaluate, in a prospective trial, a new combination chemotherapy specifically designed for elderly patients. PATIENTS AND METHODS: From October 1988 to December 1990, 60 previously untreated patients older than 60 years of age with aggressive non-Hodgkin's lymphoma (NHL) were treated at our institution with a new weekly alternating six-drug chemotherapy regimen, P-VABEC. The schedule consisted of doxorubicin, etoposide, and cyclophosphamide alternated weekly with vincristine and bleomycin. Oral prednisone was administered daily during the entire treatment period. Twenty-six of 60 patients were treated for a total of eight courses and 34 of 60 for 12 courses. RESULTS: A total of 45 patients (75%) achieved a complete response (CR), 10 (17%) a partial response (PR), and five (8%) no response. So far, 20 of 45 CR patients have relapsed, four of 10 PR patients have progressed, and three patients have died while in CR. Twenty-eight patients are still alive and responding (22 CRs, six PRs) after a median follow-up of 25 months. The projected overall survival (OS), disease-free survival (DFS), and event-free survival (EFS) rates at 2 years were 64%, 57%, and 55%, respectively. The outcome of patients treated with eight courses was similar to that of those who received 12 courses of P-VABEC in terms of CR rate and actuarial curves of OS, DFS, and EFS. Hematologic toxicity was mild in all patients. CONCLUSION: The P-VABEC regimen is active, well tolerated, and one of the briefest first-line chemotherapy regimens so far reported in the treatment of elderly patients with aggressive NHL. However, prospective randomized trials are needed to establish the real advantage of this regimen compared with other standard chemotherapy regimens.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma no Hodgkin/tratamiento farmacológico , Análisis Actuarial , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Esquema de Medicación , Etopósido/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Vincristina/administración & dosificación
19.
J Clin Oncol ; 19(3): 756-61, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11157028

RESUMEN

PURPOSE: Neutropenic enterocolitis (NE) is a severe complication of intensive chemotherapy and is barely identifiable by clinical signs alone. Ultrasonography (US) supports the diagnosis of NE by showing pathologic thickening of the bowel wall. The aim of this study was to evaluate the prognostic value of the degree of mural thickening evaluated by US in patients with clinically suspected NE. PATIENTS AND METHODS: Neutropenic patients with fever, diarrhea, and abdominal pain after intensive chemotherapy for hematologic malignancies were studied with abdominal US. We evaluated the degree of bowel wall thickening detected by US and its correlation with the duration of the clinical syndrome as well as NE-related mortality. RESULTS: Eighty-eight (6%) of 1,450 consecutive patients treated for leukemia had clinical signs of NE. In 44 (50%) of 88 patients, US revealed pathologic wall thickening (mean +/- SD, 10.2 +/- 2.9 mm; range, 6 to 18). The mean duration of symptoms was significantly longer in this group (7.9 days) than among patients without mural thickening (3.8 days, P <.0001), and the NE-related mortality rate was higher (29.5% v 0%, P <.001). Patients with bowel wall thickness of more than 10 mm had a significantly higher mortality rate (60%) than did those with bowel wall thickness < or = 10 mm (4.2%, P <.001). CONCLUSION: Symptomatic patients with sonographically detected bowel wall thickening have a poor prognosis compared with patients without this finding. In addition, mural thickness of more than 10 mm is associated with poorer outcome among patients with NE.


Asunto(s)
Enterocolitis/diagnóstico por imagen , Intestinos/diagnóstico por imagen , Leucemia Mieloide/complicaciones , Neutropenia/diagnóstico por imagen , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicaciones , Enfermedad Aguda , Adolescente , Adulto , Crisis Blástica/complicaciones , Crisis Blástica/tratamiento farmacológico , Niño , Enterocolitis/inducido químicamente , Enterocolitis/mortalidad , Enterocolitis/patología , Humanos , Intestinos/patología , Leucemia Mielógena Crónica BCR-ABL Positiva/complicaciones , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mieloide/tratamiento farmacológico , Linfoma no Hodgkin/complicaciones , Linfoma no Hodgkin/tratamiento farmacológico , Persona de Mediana Edad , Neutropenia/inducido químicamente , Neutropenia/mortalidad , Neutropenia/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Pronóstico , Ultrasonografía
20.
J Clin Oncol ; 11(6): 1046-54, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8501490

RESUMEN

PURPOSE: This study was conducted to assess the comparative values of allogeneic bone marrow transplantation (BMT) and autologous bone marrow transplantation (ABMT) with sequential postremission chemotherapy (SPC) in children with acute myelogenous leukemia (AML) in first remission. PATIENTS AND METHODS: From March 1987 to March 1990, 161 assessable patients younger than 15 years of age with newly diagnosed AML were treated uniformly with two courses of daunorubicin and standard-dose cytarabine. After initial consolidation with a course of daunorubicin, cytarabine, and thioguanine (DAT), patients in complete remission (CR) were randomized to receive either ABMT or SPC, except for those with an HLA-matched sibling who were assigned to undergo BMT. SPC consisted of three additional courses of DAT, followed by three pairs of drugs administered sequentially for a total of six cycles. RESULTS: Overall, 127 of 161 patients attained CR (79%). The estimated probabilities of survival and event-free survival (EFS) at 5 years for all patients were 42% and 25%, respectively (median follow-up, 28 months). For the 127 complete responders, the 5-year probability of disease-free survival (DFS) was 31%, with a cumulative risk of relapse of 64%. For the purpose of this study, all complete responders were evaluated for analysis of disease outcome according to the intent-to-treat principle, regardless of whether they actually received the intended therapy. The 5-year DFS was 51% for the BMT group (n = 24), significantly higher (P = .03) than that observed for the other cohorts: 21% for ABMT (n = 35), 27% for SPC (n = 37), and 34% for a group of 31 nonrandomized (NR) patients. Bone marrow relapse was the most frequent cause of postremission failure in all therapeutic subgroups, including the BMT cohort, in which no deaths attributable to the toxicity of the procedure were recorded. CONCLUSION: The results of this study show that BMT is more effective than ABMT or SPC in preventing leukemia relapse and extending DFS duration in children with AML in first remission.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Leucemia Mieloide Aguda/terapia , Adolescente , Niño , Preescolar , Terapia Combinada , Citarabina/administración & dosificación , Daunorrubicina/administración & dosificación , Femenino , Humanos , Lactante , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/mortalidad , Masculino , Estudios Prospectivos , Inducción de Remisión , Tasa de Supervivencia , Tioguanina/administración & dosificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA