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1.
J Clin Oncol ; 19(9): 2390-6, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11331317

RESUMEN

PURPOSE: To determine the toxicity and response rate in children treated with dexamethasone, etoposide, cisplatin, high-dose cytarabine, and L-asparaginase (DECAL) for recurrent non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). PATIENTS AND METHODS: Ninety-seven children with recurrent NHL (n = 68) or HD (n = 29) were enrolled. Treatment consisted of two cycles of DECAL, then bone marrow transplantation or up to four cycles of ifosfamide, mesna, and etoposide alternating with DECAL maintenance therapy. RESULTS: After two cycles of DECAL induction therapy, complete response (CR) or partial response (PR) was reported in 19 (65.5%; 10 CRs and nine PRs) of 29 patients with HD and 29 (41.6%; 23 CRs and six PRs) of 68 patients with NHL. When only 24 patients with HD and 58 patients with NHL who were assessable for response were considered, the response rates were 79.2% (19 of 24 patients) and 50.0% (29 of 58 patients), respectively. Five-year event-free survival was 26% +/- 9% and 23% +/- 5% in patients with HD and NHL, respectively. Five-year survival was 31% +/- 14% and 30% +/- 6%, respectively. Although median time to treatment failure was significantly longer in patients with HD (EFS, P =.002; survival, P =.011), this difference did not translate into a higher long-term survival. Grade 3 or 4 toxic effects were observed during induction in 70 (72%) of 97 patients and during maintenance in 45 (70%) of 64 courses of DECAL therapy. Pancytopenia and systemic infections in particular were frequently observed. Other toxic effects were uncommon. Although not a formal part of the therapy or the study design, 42 patients who responded to therapy who underwent bone marrow transplant did not show any benefit from this approach. CONCLUSION: DECAL is an effective and tolerable salvage regimen for treating patients with recurrent NHL and HD.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Enfermedad de Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/tratamiento farmacológico , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Asparaginasa/administración & dosificación , Niño , Citarabina/administración & dosificación , Dexametasona/administración & dosificación , Etopósido/administración & dosificación , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Enfermedad de Hodgkin/mortalidad , Humanos , Linfoma no Hodgkin/mortalidad , Masculino , Tasa de Supervivencia
2.
Blood ; 97(1): 56-62, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11133742

RESUMEN

Intensive, myelosuppressive therapy is necessary to maximize outcomes for patients with acute myeloid leukemia (AML). A comparison was made of 3 aggressive postremission approaches for children and adolescents with AML in a randomized trial, CCG-2891. A total of 652 children and adolescents with AML who achieved remission on 2 induction regimens using identical drugs and doses (standard and intensive timing) were eligible for allocation to allogeneic bone marrow transplantation (BMT) based on matched related donor status (n = 181) or randomization to autologous BMT (n = 177) or to aggressive high-dose cytarabine-based chemotherapy (n = 179). Only 115 patients (18%) refused to participate in the postremission phase of this study. Overall compliance with the 3 allocated regimens was 90%. At 8 years actuarial, 54% +/- 4% (95% confidence interval) of all remission patients remain alive. Survival by assigned regimen ("intent to treat") is as follows: allogeneic BMT, 60% +/- 9%; autologous BMT, 48% +/- 8%; and chemotherapy, 53% +/- 8%. Survival in the allogeneic BMT group is significantly superior to autologous BMT (P =.002) and chemotherapy (P =.05); differences between chemotherapy and autologous BMT are not significant (P =.21). No potential confounding factors affected results. Patients receiving intensive-timing induction therapy had superior long-term survival irrespective of postremission regimen received (allogeneic BMT, 70% +/- 9%; autologous BMT, 54% +/- 9%; chemotherapy, 57% +/- 10%). Allogeneic BMT remains the treatment of choice for children and adolescents with AML in remission, when a matched related donor is available. For all others, there is no advantage to autologous BMT; hence, aggressive nonablative chemotherapy should be used.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea/normas , Leucemia Mieloide/terapia , Análisis Actuarial , Enfermedad Aguda , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidad , Niño , Preescolar , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Leucemia Mieloide/complicaciones , Inducción de Remisión , Factores de Riesgo , Tasa de Supervivencia , Trasplante Autólogo/normas , Trasplante Homólogo/normas , Resultado del Tratamiento
3.
J Clin Oncol ; 17(11): 3426-30, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10550137

RESUMEN

PURPOSE: To determine if inhibition of stem-cell activity induced by granulocyte-macrophage colony-stimulating factor ([GM-CSF]; Sargramostim; Immunex Corporation, Seattle, WA) withdrawal or priming protects hematopoietic stem cells from the cytotoxic effects of adjuvant chemotherapy for early-stage breast cancer. PATIENTS AND METHODS: Serial blood counts were performed in 20 women with early-stage breast cancer receiving four courses of cyclophosphamide and doxorubicin chemotherapy. By a double-blind, placebo-controlled, balanced randomization, subjects received GM-CSF priming on days 5 to 1 for courses 1 and 3 or courses 2 and 4. RESULTS: Compared with before priming, after priming the times to neutrophil nadir (12.8 +/- 2.5 days v 14.8 +/- 1.5 days, respectively; P =.0001) and platelet nadir (mean +/- SD, 10.1 +/- 1.9 days v 11.1 +/- 2.2 days, P <.05) were shorter, indicating a shift of cytotoxicity to later progenitors. The neutrophil nadir was similar with and without priming (mean +/- SD, 490 +/- 310/microL v 550 +/- 350/microL, respectively; P =.2); however, on day 16 the mean neutrophil count was higher (mean +/- SD, 1030 +/- 580/microL v 690 +/- 370/microL, P =.004), and the proportion of patients with a neutrophil count less than 500/microL was lower after priming than before (six of 35 or 17. 1% v 12 of 34 or 35.3%, respectively; P =.04). The platelet nadir was higher (mean +/- SD, 166,000 +/- 51,000/microL after priming v 151,000 +/- 45,000/microL before priming, P =.007), and the duration of thrombocytopenia, ie, a platelet count less than 150,000/microL, was shorter (1.5 +/- 2.1 days v 2.8 +/- 2.9 days, P =.0025) after priming. Episodes of fever and neutropenia were not observed. CONCLUSIONS: GM-CSF priming from days 5 to 1 before doxorubicin and cyclophosphamide chemotherapy was associated with an earlier neutrophil and platelet nadir. On day 16, a higher mean neutrophil count and a lower proportion of patients with severe (< 500/microL) neutropenia were observed. Beneficial effects on the severity and duration of thrombocytopenia were also noted. These observations support the hypothesis that GM-CSF priming protects hematopoietic progenitors from the cytotoxic effects of chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Adulto , Anciano , Ciclofosfamida/administración & dosificación , Método Doble Ciego , Doxorrubicina/administración & dosificación , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos y Macrófagos/efectos adversos , Humanos , Persona de Mediana Edad
4.
J Neurooncol ; 45(1): 47-54, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10728909

RESUMEN

PURPOSE: This study was undertaken to evaluate the response of recurrent brain tumors to intravenous etoposide and to evaluate the efficacy of mannitol in augmenting etoposide's tumoricidal effect. PATIENTS AND METHODS: Ninety-nine children between one and 21 years of age with recurrent brain tumors were randomly assigned to treatment with intravenous etoposide 150 mg/M2, with or without mannitol 15 gm/M2, daily for five days every three weeks for one year or until disease progression or death. Computerized tomographic (CT) or magnetic resonance image (MRI) scans, obtained after three cycles of therapy, were compared with pre-therapy scans. Scans were centrally reviewed. RESULTS: Of 87 evaluable patients, 12 (13.8%) were determined to have had an objective response by the institutional radiologist. On central review, 7/66 (10.6%) responses were documented. Responses in centrally reviewed patients were observed in 2/12 (16.7%) low grade astrocytomas, 4/26 (15.4%) medulloblastoma or primitive neuroectodermal tumors (PNET), 1/13 (7.7%) high grade astrocytomas and 0/15 (0%) brain stem gliomas. Survival at one year was 53% (SE 12%) for low grade astrocytomas, 38% (SE 7%) for medulloblastoma or PNET, 28% (SE 10%) for high grade astrocytomas and 9% (SE 5%) for brain stem gliomas. An effect of mannitol was not observed. CONCLUSION: Intravenous etoposide has a low level of activity in the treatment of recurrent low grade astrocytomas and medulloblastoma or PNET. The efficacy of this agent was not enhanced by the coincident intravenous administration of mannitol.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Etopósido/uso terapéutico , Manitol/uso terapéutico , Adolescente , Antineoplásicos Fitogénicos/efectos adversos , Neoplasias Encefálicas/diagnóstico , Niño , Quimioterapia Combinada , Etopósido/efectos adversos , Femenino , Humanos , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Masculino , Manitol/efectos adversos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Análisis de Supervivencia , Insuficiencia del Tratamiento
5.
Cancer Invest ; 14(3): 202-10, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8630680

RESUMEN

High-dose acetaminophen (HDAC) produces hepatocellular necrosis and cytotoxic changes in other tissues that express mixed-function-oxidase (MFO) activity. N-acetylcysteine (NAC), administered within 8 hr of HDAC exposure, replenishes reduced glutathione and prevents these effects. Numerous cell culture and animal studies have demonstrated that NAC may differentially protect normal cells compared with malignant cells from the toxic effects of chemotherapeutic agents and radiation. It was therefore proposed that HDAC with NAC rescue may be effective in malignancies that express MFO activity. To test this hypothesis, a phase I trial of HDAC with NAC rescue was conducted on 19 patients with advanced cancer. HDAC was escalated from 6 to 20 g/m2 PO using a standard IV NAC rescue regimen. A total of 78 treatments were administered. Moderate fatigue, anorexia, and weight loss were the main toxicities observed. Transient grade 3 liver toxicity was noted following 1 treatment. Alopecia and renal and hematological toxicities were not observed. Responses after 4 courses administered weekly were as follows: response in at least 1 site-8 (partial 3, improved 3, mixed 2); stable disease-3; progressive disease-3; inevaluable-5. In conclusion, HDAC was tolerated with moderate fatigue, anorexia, and weight loss but few other effects using a standard IV NAC rescue regimen. A maximum tolerated dose was not reached at 20 g/m2. A 3/19 (15.8%) partial response rate was observed.


Asunto(s)
Acetaminofén/administración & dosificación , Acetilcisteína/uso terapéutico , Antineoplásicos/administración & dosificación , Neoplasias/tratamiento farmacológico , Acetaminofén/efectos adversos , Acetilcisteína/farmacocinética , Adulto , Anciano , Carcinoma de Células Pequeñas/tratamiento farmacológico , Combinación de Medicamentos , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Factores de Tiempo
6.
J Child Neurol ; 10(2): 105-9, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7782598

RESUMEN

To determine the effect of iron status on the seizure threshold, measures of iron sufficiency were prospectively evaluated in 51 children presenting to a pediatric emergency department with a febrile illness with (26) or without (25) an associated febrile seizure. A higher proportion of children from the febrile seizure group had a family history of mental retardation (5/26 versus 0/25, P = .02) or of previous febrile seizures (10/26 versus 2/23, P = .01). The two groups were otherwise comparable for age, sex, race, family history of afebrile seizures, temperature at presentation, white blood cell count, differential, and vitamin and antibiotic use. Patients with febrile seizures were less frequently iron deficient as defined by a free erythrocyte protoporphyrin level above 0.80 ng/L (2/23 versus 10/25, P < .01), hemoglobin concentration less than 110 g/L (1/26 versus 6/25, P < .03), hematocrit less than 0.30 L/L (0/22 versus 4/25, P < .02), mean corpuscular hemoglobin less than 20 pg (0/25 versus 3/24, P < .04), mean corpuscular volume less than 65 fL (0/26 versus 4/24, P < .02), and platelet count higher than 550 x 10(9)/L (0/26 versus 3/25, P < .04). This association was even stronger when adjusted for differences in family history. None of the patients in the febrile seizure group was being treated for iron deficiency at presentation, whereas three of 25 controls used an iron supplement (P < .04). Iron deficiency may protect against the development of febrile seizures.


Asunto(s)
Anemia Ferropénica/fisiopatología , Electroencefalografía , Hierro/sangre , Convulsiones Febriles/fisiopatología , Corteza Cerebral/fisiología , Preescolar , Eritrocitos/metabolismo , Potenciales Evocados/fisiología , Femenino , Hematócrito , Hemoglobinometría , Humanos , Lactante , Peroxidación de Lípido/fisiología , Masculino , Estudios Prospectivos , Protoporfirinas/sangre , Factores de Riesgo
7.
Biochem Pharmacol ; 46(6): 1071-5, 1993 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-8216350

RESUMEN

The effect of the adenosine deaminase (ADA) inhibitor 2'-deoxycoformycin (dCF) on the development of insulin-dependent diabetes mellitus (IDDM) was assessed in the BB Wistar rat. Sixty-one male rats were treated from days 30 to 120 with 0, 0.5, 1.0 or 1.5 mg dCF/kg/week. The incidence of IDDM was 78% in the controls and was significantly (P < 0.01) decreased in rats receiving 1.5 mg dCF/kg/week (32%), but not in rats receiving lower doses of the drug. However, for those rats that became diabetic the mean time to the development of IDDM was unchanged in animals receiving dCF compared with control. dCF treatment did not produce significant weight loss in the animals or gross changes in the thymus, spleen or kidneys. Although the protective effect of dCF against IDDM was likely produced by immunosuppression, the different dCF dosages had similar effects on ADA suppression in spleen or thymus and on dATP accumulation in these organs.


Asunto(s)
Diabetes Mellitus Tipo 1/prevención & control , Pentostatina/farmacología , Inhibidores de la Adenosina Desaminasa , Animales , Nucleótidos de Desoxiadenina/metabolismo , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Endogámicas BB/genética , Bazo/efectos de los fármacos , Bazo/enzimología , Timo/efectos de los fármacos , Timo/enzimología
9.
Pediatrics ; 90(1 Pt 1): 33-6, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1614775

RESUMEN

The relationship between bleeding and bruising and the production of prostacyclin and thromboxane was assessed in children who were to have a tonsillectomy and/or an adenoidectomy. Eicosanoids in the blood oozing from the bleeding time incision were measured and correlated with the reported frequency of bruising and epistaxis. A striking association (P = .0003) between prostacyclin production and the frequency of bruising was found; children reporting bleeding at least biweekly had the highest prostacyclin synthesis. Successively lower levels of the prostacyclin metabolite, 6-keto-prostaglandin F1 alpha, were found in children reporting less frequent bruising. Prostacyclin production in bleeding time blood was also correlated inversely with systolic blood pressure and hemoglobin level, although neither of these variables could explain the association between prostacyclin production and bruising. There was no correlation between thromboxane formation, systolic blood pressure, hemoglobin level, age, or bleeding time and the frequency of bruising. The ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha was correlated inversely with the length of the bleeding time (P = .016). It is concluded that vascular prostacyclin production may have a role in bruising symptomatology. It is suggested that prostacyclin formed at the injured vessel surface collects within the first few seconds after injury inside the tissue space at the site of the bruise and, by influencing the formation of the platelet/fibrin plug and/or the leakage of blood from the vessels, plays a significant role in modifying the development of bruising.


Asunto(s)
6-Cetoprostaglandina F1 alfa/sangre , Contusiones/sangre , Epoprostenol/biosíntesis , Tromboxano B2/sangre , Adolescente , Tiempo de Sangría , Recuento de Células Sanguíneas , Niño , Preescolar , Contusiones/metabolismo , Epoprostenol/metabolismo , Humanos , Factores Sexuales , Tromboxanos/biosíntesis , Tromboxanos/metabolismo
10.
Surg Neurol ; 37(5): 410-4, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1631771

RESUMEN

A case of primary central nervous system malignant rhabdoid tumor is presented. Clinical, radiological, and histopathological findings are described in detail. Because of a relatively long clinical course after presentation, it was possible to assess the clinical and radiological response to different treatment modalities: surgery, chemotherapy, and radiotherapy. Despite the complete clinical and radiological response that was achieved after subtotal excision, two cycles of chemotherapy, and high-dose radiotherapy, the tumor recurred within 4 months of completion of the treatment, with wide subarachnoid dissemination. Radiotherapy treatment of whole cranial axis is recommended.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Espacio Subaracnoideo/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Preescolar , Terapia Combinada , Humanos , Masculino , Invasividad Neoplásica , Recurrencia Local de Neoplasia , Espacio Subaracnoideo/patología , Espacio Subaracnoideo/cirugía , Tomografía Computarizada por Rayos X
11.
Hemoglobin ; 16(1-2): 19-25, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1634359

RESUMEN

We have identified the unstable hemoglobin variant present in a Chipewayan Indian patient with severe hemolytic anemia as Hb Hammersmith or alpha 2 beta 2(42)(CD1)Phe----Ser. Her parents were normal. Identification was greatly facilitated by the use of reversed phase high performance liquid chromatography for the isolation of the beta X chain and its tryptic fragments, and of sequence analysis of amplified DNA which readily identified a TTT(Phe)----TCT(Ser) mutation at codon 42.


Asunto(s)
Hemoglobinas Anormales/genética , Secuencia de Bases , Cromatografía Líquida de Alta Presión , ADN/genética , Femenino , Amplificación de Genes/genética , Globinas/aislamiento & purificación , Humanos , Indígenas Norteamericanos , Mutación/genética
12.
Am J Pediatr Hematol Oncol ; 13(4): 437-41, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1785670

RESUMEN

Desmopressin and ethamsylate were evaluated for possible synergistic effects on the bleeding time. The drugs were administered individually and together to 12 patients with markedly prolonged bleeding times known to be relatively or absolutely unresponsive to desmopressin alone. The bleeding disorders studied included Glanzmann's thrombasthenia (one), other disorders of platelet function (four), pseudo-von Willebrand disease (one), and von Willebrand disease type I (three), type II (two), and type III (one). Desmopressin alone shortened the bleeding time from 23.9 +/- 1.5 to 19.5 +/- 2.3 min (p = 0.03). Ethamsylate alone was without effect. Desmopressin and ethamsylate together shortened the bleeding time to 11.2 +/- 1.4 min (p less than 0.01 compared to baseline, p = 0.02 compared to desmopressin alone). The combination was ineffective in three patients, with Glanzmann's thrombasthenia (one), and von Willebrand disease type I (one) and type III (one). Toxic effects of the drugs were not observed. Five patients received desmopressin and ethamsylate prior to dental work with mandibular block (one), heart surgery requiring cardiopulmonary bypass (two), and adenotonsillectomy surgery (two). Normal hemostasis was achieved in each case. A synergistic shortening of the bleeding time was observed with the combination of desmopressin and ethamsylate in a wide range of bleeding disorders.


Asunto(s)
Tiempo de Sangría , Trastornos de las Plaquetas Sanguíneas/tratamiento farmacológico , Desamino Arginina Vasopresina/uso terapéutico , Etamsilato/uso terapéutico , Adolescente , Adulto , Anciano , Trastornos de las Plaquetas Sanguíneas/sangre , Niño , Preescolar , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad
13.
Am J Pediatr Hematol Oncol ; 13(2): 160-3, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2069224

RESUMEN

The mutagenic activity of urine was evaluated in children receiving single and multiple agent chemotherapy to determine the duration of carcinogenic risk to health care personnel and family contacts. Urine samples from 21 children were evaluated before and daily for 5 days after chemotherapy administration. Mutagenic activity, a sensitive though not specific indicator of carcinogenic risk, was assayed using mutant strains of Salmonella typhimurium (the "Ames test"). Validity of the assay was confirmed by demonstrating mutagenic activity in urine samples from 17 adult cigarette smokers but not from 21 adult nonsmokers (24/24 versus 0/37, p less than 0.001). None of the 21 children tested demonstrated mutagenic activity before chemotherapy administration. Following single agent dactinomycin, cyclophosphamide, daunorubicin, doxorubicin, methotrexate, or vincristine, mutagenic activity was demonstrated for 2 days (5/5 at 1 and 2 days and 0/5 at 3 days). Following multiple agent chemotherapy using two or three of the latter drugs on a single day, mutagenic activity was demonstrated for 4 or 5 days (16/16 at 1, 2, 3, and 4 days, and 4/16 at 5 days). Based on these observations with urine, and presumably other body fluids, precautions are recommended for 2 days following single agent and at least 5 days following multiple agent chemotherapy.


Asunto(s)
Antineoplásicos/efectos adversos , Mutágenos/orina , Adulto , Carcinógenos , Niño , Humanos , Pruebas de Mutagenicidad/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/orina , Salmonella typhimurium , Fumar/orina
15.
Clin Invest Med ; 12(3): 165-71, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2787219

RESUMEN

In order to provide an overview of the relative contribution of platelet, von Willebrand factor, and other abnormalities to patients with clinical bleeding difficulties, we performed a retrospective survey of coagulation studies on 569 individuals referred to the University of Manitoba coagulation laboratory because they, or a closely related family member, showed clinical evidence of a bleeding disorder. There was a highly significant (p less than 0.001) negative correlation between the bleeding time and each of the following parameters: the platelet count; the hematocrit; the percent aggregation to collagen, epinephrine, ADP, and arachidonic acid; and the logarithm of von Willebrand factor antigen and a measure of its activity (ristocetin cofactor). A significant and independent inverse relationship between the length of the bleeding time and the extent of platelet adhesion to glass beads, patient age, and prothrombin consumption were also observed. Multivariate analysis of the ability of all parameters to predict the bleeding time showed an r2 of only 0.33. Bleeding time thromboxane B2, in a second smaller study of 70 patients, showed a negative correlation with the length of the bleeding time (p = 0.0001), and, when used together with the above parameters, significantly enhanced the ability to predict the length of the bleeding time (r2 = 0.55). Defects in platelet function, as measured in vitro, and significant enough to have an effect on the bleeding time, occurred with greater frequency than defects in von Willebrand factor in the Manitoba patients evaluated.


Asunto(s)
Tiempo de Sangría , Trastornos de la Coagulación Sanguínea/diagnóstico , Pruebas de Función Plaquetaria , Tromboxano B2/sangre , Factor de von Willebrand/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Trastornos de la Coagulación Sanguínea/metabolismo , Trastornos de la Coagulación Sanguínea/fisiopatología , Niño , Preescolar , Femenino , Hematócrito , Humanos , Masculino , Persona de Mediana Edad
16.
Circulation ; 79(1): 29-38, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2910545

RESUMEN

The effects of smoking, aspirin ingestion, and sex differences on bleeding times and bleeding time thromboxane B2 and 6-keto-prostaglandin (PG)F1 alpha production were examined. Nonsmoking men produced more thromboxane B2 (3.99 +/- 0.76 ng/ml) than nonsmoking women (2.13 +/- 0.24 ng/ml). Female smokers produced more thromboxane B2 (5.01 +/- 0.97 ng/ml) than nonsmoking women. Twenty-four hours after a single dose of 600 mg aspirin, in vitro production of thromboxane B2 in response to collagen fell by 95%, whereas in vivo production of thromboxane B2 and 6-keto-PGF1 alpha in bleeding time blood fell by 87% and 66%, respectively. Subjects with the lowest absolute levels of thromboxane B2 24 hours after aspirin were also those with the longest postaspirin bleeding times. Recovery of 6-keto-PGF1 alpha production was faster than recovery of thromboxane B2 production, but 6-keto-PGF1 alpha production for most subjects was still below basal 72 hours after aspirin. The influence of two different doses of long-term aspirin (80 mg every other day and 325 mg daily) on the in vivo production of thromboxane B2 and 6-keto-PGF1 alpha was studied in normals and diabetics. After 14 days of 80 mg aspirin every other day, thromboxane B2 and 6-keto-PGF1 alpha production were both substantially inhibited (93% and 78%, respectively). After 14 days of 325 mg aspirin daily, thromboxane B2 production was similarly substantially inhibited (93%), whereas 6-keto-PGF1 alpha was significantly less affected (only 45% inhibition). Study of a second group of five normal subjects confirmed that 6-keto-PGF1 alpha production was significantly inhibited 24 hours after the first dose of 325 mg aspirin but was not significantly less than basal after 14 days of 325 mg aspirin. The results suggest that 325 mg aspirin daily is more antithrombotic compared with 80 mg every other day due to the superior preservation of prostacyclin production.


Asunto(s)
6-Cetoprostaglandina F1 alfa/sangre , Aspirina/farmacología , Tromboxano B2/sangre , 6-Cetoprostaglandina F1 alfa/biosíntesis , Adulto , Aspirina/administración & dosificación , Tiempo de Sangría , Diabetes Mellitus/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Fumar , Tromboxano B2/biosíntesis , Factores de Tiempo
19.
Am J Pediatr Hematol Oncol ; 10(3): 206-8, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3052143

RESUMEN

To evaluate the role of endogenous opiates in chemo-therapy-induced nausea and vomiting, the narcotic-antagonist naloxone was administered to six pediatric patients receiving cancer chemotherapy. Naloxone was administered by continuous intravenous (i.v.) infusion after randomized, double-blind controlled assignment at a dose of 0, 10 or 40 micrograms/kg/h for 12 h. Each patient was studied for four consecutive and identical courses of chemotherapy (eight courses for each naloxone dose or 24 courses in all). A dose-related increase in nausea (nausea score 2.5 +/- 2.24, 3.83 +/- 2.73, and 5.75 +/- 2.86/12 h, p = 0.003), vomiting (emetic events 6.0 +/- 7.50, 8.08 +/- 6.71, and 10.3 +/- 8.91/12 h, p = 0.035), and patient aversion (course preference rank 1.5 +/- 0.45, 2.83 +/- 1.17, and 3.25 +/- 0.42/4 courses, p = 0.014) was observed. The infusion of naloxone in the absence of chemotherapy was without effect. These results support a role for endogenous opiates in regulating chemotherapy-induced nausea and vomiting, and further suggest that narcotic agents may be effective antiemetics in this setting.


Asunto(s)
Antineoplásicos/efectos adversos , Naloxona/efectos adversos , Náusea/inducido químicamente , Vómitos/inducido químicamente , Adolescente , Antineoplásicos/administración & dosificación , Células Quimiorreceptoras/efectos de los fármacos , Niño , Preescolar , Ensayos Clínicos como Asunto , Sinergismo Farmacológico , Endorfinas/antagonistas & inhibidores , Endorfinas/fisiología , Femenino , Humanos , Masculino , Naloxona/administración & dosificación , Neoplasias/tratamiento farmacológico , Distribución Aleatoria
20.
Am J Pediatr Hematol Oncol ; 10(3): 209-13, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3052144

RESUMEN

Chemotherapy-induced nausea and vomiting are primarily regulated by chemoreceptor trigger zone (CTZ)-vomiting center (VC) pathways. Dopaminergic (D2), histaminic (H1), and muscarinic cholinergic (Ach) receptors are present in these sites, and specific receptor antagonists are potent but not "universal" antiemetics when used alone or in combination. Recently, neurons containing the endogenous opiate enkephalin were also identified near the CTZ and the VC. Furthermore, opiates stimulate vomiting at the CTZ and inhibit vomiting at the VC in dogs and in cats. A dose-related increase in nausea and vomiting in response to the opiate antagonist naloxone has also been demonstrated in patients receiving cancer chemotherapy. These observations support a role for endogenous opiates in regulating chemotherapy-induced nausea and vomiting; further, they suggest that narcotic agents may be effective antiemetics in this setting.


Asunto(s)
Antineoplásicos/efectos adversos , Náusea/inducido químicamente , Vómitos/inducido químicamente , Células Quimiorreceptoras/efectos de los fármacos , Células Quimiorreceptoras/fisiología , Niño , Endorfinas/antagonistas & inhibidores , Endorfinas/fisiología , Humanos , Naloxona/farmacología , Náusea/fisiopatología , Neoplasias/tratamiento farmacológico , Vómitos/fisiopatología
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