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1.
Br J Pharmacol ; 161(1): 79-91, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20718741

RESUMO

BACKGROUND AND PURPOSE: Myocardial ischaemia is associated with perturbations of electrophysiological profile of cardiac myocytes. The persistent sodium current (I(Nap)) is one of the major contributors to ischaemic arrhythmias and appears as an attractive therapeutic target. We investigated the effects of F 15845, a new anti-anginal drug on I(Nap) and in integrative models of I(Nap)-induced arrhythmias. EXPERIMENTAL APPROACH: Sodium current was investigated using patch clamp technique on wild-type and DeltaKPQ-mutated hNav1.5 channels transfected in HEK293 cells. Effects of F 15845 on action potentials (APs) were studied by the glass microelectrode technique and its anti-arrhythmic activities were investigated in ischaemia- and aconitine-induced arrhythmias in the rat. KEY RESULTS: We demonstrated that F 15845 is a potent blocker of I(Nap) acting from the extracellular side of the channel. Blockade of I(Nap) was voltage dependent and characterized by an almost pure tonic block. F 15845 shortened AP from rabbit Purkinje fibres, confirming its lack of pro-arrhythmic activity, and prevented AP lengthening induced by the I(Nap) activator veratridine. F 15845 did not affect APs from rabbit atria and guinea pig papillary muscle where I(Nap) is not functional, confirming its inability to affect other cardiac ionic currents. F 15845 was effective at preventing fatal ventricular fibrillation and ventricular tachycardia during coronary ligation without modifying heart rate and blood pressure, and dose dependently increased the dose threshold of aconitine required to induce ventricular arrhythmias. CONCLUSIONS AND IMPLICATIONS: F 15845, a novel anti-anginal drug targeting I(Nap), demonstrates new anti-arrhythmic properties which may be of therapeutic benefit against ischaemia-induced arrhythmias.


Assuntos
Arritmias Cardíacas/prevenção & controle , Benzotiepinas/farmacologia , Isquemia Miocárdica/complicações , Bloqueadores dos Canais de Sódio/farmacologia , Canais de Sódio/metabolismo , Aconitina , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/metabolismo , Linhagem Celular , Átrios do Coração/efeitos dos fármacos , Átrios do Coração/metabolismo , Humanos , Masculino , Técnicas de Patch-Clamp , Ramos Subendocárdicos/efeitos dos fármacos , Ramos Subendocárdicos/fisiologia , Coelhos , Ratos , Ratos Sprague-Dawley , Suínos , Veratridina/farmacologia
2.
Naunyn Schmiedebergs Arch Pharmacol ; 363(4): 464-71, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11330341

RESUMO

The clinical anti-anginal effectiveness of ranolazine is currently being evaluated. However, the mechanism of its anti-ischaemic action is still unclear. The aim of this work was to establish whether ranolazine exerts functional beta-adrenoceptor antagonist activity in the rat cardiovascular system. Radioligand binding studies were performed in rat hearts and guinea-pig lungs for beta1- and beta2-adrenoceptor affinity, respectively. Ranolazine had micromolar affinity for both beta,- and beta2-adrenoceptors (pKi5.8 and 6.3, respectively). Developed tension was measured in isolated rat left atria (electrically driven at 4 Hz) and cumulative concentration/response curves to (+/-)isoprenaline (0.01-1,000 nM) constructed. Ranolazine (0.32-10 microM) surmountably but weakly antagonised isoprenaline-induced positive inotropic responses, with an apparent pA2 of 5.85 (5.69-6.00) and a slope of -0.74 (-0.70 to -0.77). In bivagotomised, atropinised pithed rats, ranolazine per se evoked marked bradycardia at doses above 10 mg/kg i.v. (maximum variation at 80 mg/kg -125+/-15 bpm, n=6, P<0.001) by a mechanism apparently unrelated to blockade of beta1- or beta2-adrenoceptors. Cumulative incremental doses of (+/-)isoprenaline (0.63 ng/kg to 0.16 mg/kg i.v.) administered to pithed rats induced concomitant depressor and chronotropic responses. Animals received either vehicle (saline 0.9% i.v., n=12), atenolol (0.04-2.5 mg/kg i.v., n=6 per dose), ICI 118551 (0.01-0.63 mg/kg i.v., n=6 or 7 per dose), (+/-)propranolol (0.01-0.63 mg/kg i.v., n=6 per dose) or ranolazine (2.5-80 mg/kg i.v., n=6 or 7 per dose) 10 min prior to isoprenaline. Ranolazine dose-dependently and competitively antagonised isoprenaline-induced decreases in diastolic arterial pressure (DAP, dose ratio 12.2 with 80 mg/kg ranolazine) and increases in heart rate (HR, dose ratio 20.3 with 80 mg/kg ranolazine). Collectively, these results demonstrate that ranolazine behaves as a weak beta1- and beta2-adrenoceptor antagonist in the rat cardiovascular system.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Contração Miocárdica/efeitos dos fármacos , Piperazinas/farmacologia , Receptores Adrenérgicos beta/efeitos dos fármacos , Acetanilidas , Animais , Inibidores Enzimáticos/metabolismo , Cobaias , Hemodinâmica/efeitos dos fármacos , Isoproterenol/antagonistas & inibidores , Masculino , Piperazinas/metabolismo , Ranolazina , Ratos , Ratos Sprague-Dawley
3.
Bull Cancer ; 88(4): 419-25, 2001 Apr.
Artigo em Francês | MEDLINE | ID: mdl-11371378

RESUMO

Ductal carcinoma in situ (DCIS), a non metastazing lesion of the breast is more frequently observed due to the improvement of mammography and widespread use of screening. The most important risk of this disease is local recurrence. In about half of cases, it occurs as an infiltrating carcinoma. In a series of 166 DCIS treated by lumpectomy plus radiotherapy, we have studied clinico-pathological factors for the prognosis of local recurrences and particularly the Van Nuys Index criteria (nuclear grade, necrosis, size, margin width). After median follow up of 75 months, 21 recurrences were observed with 10 corresponding to an infiltrating carcinoma and one of them died. The size of DCIS evaluated on pathological documents (histological slides and shames), the Van Nuys Prognostic Index (VNPI) and the mitotic index were the main prognostic factors of local recurrence. We discuss these results and confront them to a review of the literature focalised on the delicate problem of the decision of conservative treatment. A multidisciplinary approach (Breast : Surgeon, Radiologist, Pathologist and Radiotherapist), a standardisation of pathological criteria (size, margin width) and the continuation of randomised trials are necessary to fine the best attitude of conservative therapy.


Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Mastectomia Segmentar , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Mama/patologia , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Índice Mitótico , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Prognóstico , Radioterapia Adjuvante
4.
Radiother Oncol ; 59(2): 195-201, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11325449

RESUMO

BACKGROUND AND PURPOSE: A retrospective study comparing chemotherapy and radiation, esophagectomy alone versus preoperative radiochemotherapy and surgery in localized squamous-cell esophageal carcinoma. MATERIALS AND METHODS: Between 1989 and 1995, 139 patients (40 stage I, 77 stage IIA and 22 stage IIB according to the UICC 78 TNM classification) were treated in two different institutions. They were divided into three groups according to the treatment proposed: E group (treatment by esophagectomy; n = 30), RCT+E group (treatment by preoperative radiochemotherapy and esophagectomy; n = 46), RCT group (treatment by radiochemotherapy; n = 63). Factors like age, tumor localization and stage were similar in all groups. An intention to treat analysis was made. RESULTS: The E group showed no postoperative mortality, while in the RCT+E group, the surgery mortality was 12.8%. The mortality after RCT was 1.7%. After preoperative radiochemotherapy, a pathological complete response was observed in 25% of cases and the curative resection rate was higher (82% after RCT + E versus 60% after E). The 5-year survival difference between the three groups was not relevant (E group, 12.6%; RCT group, 25.8%; RCT + E group, 38.7%). The median survival was 29, 24 and 28.5 months, respectively. The event-free survival was identical for the E group and the RCT group. For patients treated by radiochemotherapy, local and/or distant relapses were significantly reduced by esophagectomy (relapses occurred in 51% of patients in the RCT + E group versus 75% in the RCT group, P = 0.017). Palliative care (dilatations, prosthesis, gastrostomy or jejunostomy) to improve dysphagia was necessary for 38% of patients treated by exclusive radiochemotherapy versus 11% of patients treated by surgery (P = 0.001). CONCLUSIONS: Treatments by esophagectomy or radiochemotherapy were not significantly different. Preoperative radiochemotherapy and surgery lead to a higher survival rate than exclusive radiochemotherapy, however, with a high postoperative mortality rate. This study suggests the relevance of a prospective randomized trial to compare RCT+E and RCT alone.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/mortalidade , Causas de Morte , Cisplatino/administração & dosagem , Terapia Combinada , Neoplasias Esofágicas/mortalidade , Esofagectomia/mortalidade , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Cuidados Paliativos , Dosagem Radioterapêutica , Estudos Retrospectivos , Análise de Sobrevida
6.
J Cardiovasc Pharmacol ; 32(3): 435-42, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9733357

RESUMO

The effects of the 5-HT1B/D receptor agonist, sumatriptan, on coronary flow (CF) and left ventricular function in the isolated perfused guinea pig heart were investigated in the presence and absence of coronary endothelial dysfunction induced by nitric oxide (NO) synthase inhibition with Nomega-nitro-L-arginine methyl ester (L-NAME; 10 microM). Hearts were perfused under constant pressure (80 cm H2O) with oxygenated (95% O2/5% CO2) Krebs bicarbonate buffer (pH 7.4) and were driven at 4 Hz. In the absence of L-NAME (n=37), sumatriptan (0.1-32 microM) failed statistically significantly to affect left ventricular developed pressure (LVDP; maximal change, -8.1+/-1.8%; NS vs. vehicle), left ventricular end-diastolic pressure (LVEDP; +10.4+/-9.8%, NS), or CF (-12.2+/-1.4%; NS compared with vehicle). L-NAME per se significantly reduced coronary flow (CF; -26.3+/-2.9%; p < 0.001), thereby increasing coronary vascular tone, and decreased LVDP (-17.1+/-1.8%; p < 0.01). In hearts perfused with L-NAME (10 microM; n=61), sumatriptan (0.1-32 microM) still failed significantly to affect CF (maximal change, 0.2+/-5.7%, NS) but concentration-dependently increased LVEDP [maximal increase, 89.0+/-30.3%; p < 0.05; geometric mean EC50 3.6 (2.9-5.7) microM], which was not prevented by the 5-HT1B/D receptor antagonist, GR 127935 (0.1 microM; maximal increase, 51.8+/-11.1%; n=48, NS compared with sumatriptan alone). In conclusion, sumatriptan failed significantly to affect CF even in the presence of endothelial dysfunction. LV function similarly remained unaffected in normal hearts, but sumatriptan produced diastolic contracture in the presence of coronary endothelial dysfunction by a mechanism apparently not involving 5-HT1B/D receptors. Collectively the data indicate that 5-HT1B/D receptor expression or effector coupling or both are absent or low in the guinea pig heart, because no detectable functional responses were observed.


Assuntos
Circulação Coronária/efeitos dos fármacos , Oxazolidinonas , Agonistas do Receptor de Serotonina/farmacologia , Sumatriptana/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Diástole/efeitos dos fármacos , Di-Hidroergotamina/farmacologia , Endotélio Vascular/fisiologia , Cobaias , Técnicas In Vitro , NG-Nitroarginina Metil Éster/farmacologia , Oxidiazóis/farmacologia , Oxazóis/farmacologia , Perfusão , Piperazinas/farmacologia , Coelhos , Receptor 5-HT1B de Serotonina , Receptor 5-HT1D de Serotonina , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/fisiologia , Triptaminas
7.
J Clin Oncol ; 14(9): 2444-53, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8823322

RESUMO

PURPOSE: To evaluate late psychosocial sequelae in long-term survivors of Hodgkin's disease (HD) in the population of Calvados, France. PATIENTS AND METHODS: Ninety-three patients issued from the Calvados General Tumor Registry, treated from 1978 to 1990, free of relapse and second malignancy since January 1991, were enrolled onto cross-sectional case-control study. One hundred eighty-six healthy controls, matched for sex, age, and residency, were selected at random from electoral rolls. Two self-administered questionnaires were mailed in the spring of 1995. RESULTS: Compared with controls, HD patients reported (1) more physical (P < .001), role (P < .001), and cognitive (P = .015) functioning impairments, as well as dyspnea (P < .001) and chronic fatigue (P = .025), while no statistical difference was found in global health status; (2) to be more often childless (P = .04), fewer divorces or separations (P = .013), fewer changes in relationships with friends (P = .012), similar proportions at work but less ambitious professional plans (P < .001), and greater difficulties in borrowing from banks (P < .001); (3) a slight increase in the number of visits to a general practitioner (P = .05) and greater consumption of medical resources (mainly thyroid extracts, P = .05). CONCLUSION: The study demonstrated that French long-term HD survivors have good global health status and good psychologic, familial, and professional status, although difficulties in borrowing from banks remain a major limitation in daily life. Although physical, role, and cognitive functioning impairments persist that might limit their activities, HD survivors seem to have learned to cope with problems related to their disease and its treatment.


Assuntos
Doença de Hodgkin/psicologia , Qualidade de Vida , Sobreviventes/psicologia , Atividades Cotidianas , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Emprego , Feminino , França , Serviços de Saúde/estatística & dados numéricos , Nível de Saúde , Humanos , Relações Interpessoais , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Inquéritos e Questionários
8.
Cardiovasc Res ; 30(5): 689-96, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8595614

RESUMO

OBJECTIVE: In isolated, Langendorff-perfused hearts in the early stages of atherosclerosis from rabbits exposed to hypercholesterolaemia induced by 2% cholesterol feeding for 6 weeks (n = 23), and age-matched normal controls fed standard chow (n = 12), we studied baseline cardiac haemodynamics and the susceptibility of these hearts to 30 min global, normothermic ischaemia and 90 min reperfusion. METHODS: Spontaneously beating hearts were perfused with oxygenated Krebs buffer (pH 7.4) at constant pressure, and were enclosed in a thermostated water jacket at 37 degrees C. Isovolumetric left ventricular (LV) pressure was measured by means of a balloon placed in the LV cavity. An electromagnetic flow probe placed around the perfusion cannula determined coronary flow. At the end of an initial 30 min stabilisation period, several baseline cardiodynamic variables were measured, just before subjecting the hearts to 30 min ischaemia. Recovery of mechanical function and lactate dehydrogenase (LDH) and creatine phosphokinase (CPK) activities in the coronary effluent were recorded throughout 90 min reperfusion. RESULTS: Baseline spontaneous heart rate, LV developed pressure (LVDP), coronary flow and pressure-rate index (PRI) were all significantly lower in hearts from cholesterol-fed rabbits (CFR) than in age-matched controls (P < 0.01). Although large differences in several baseline haemodynamic parameters in hearts from CFR and controls were evident before ischaemia, no statistically significant differences were discernible in these parameters between the two groups from 60 min reperfusion onwards (p = NS). Furthermore, CPK and, to a lesser extent, LDH release during reperfusion was attenuated in hearts from CFR compared to controls. CONCLUSIONS: Hearts from CFR exhibited markedly improved recovery upon reperfusion compared to age-matched controls, strongly suggesting increased myocardial resistance to ischaemic injury.


Assuntos
Doença da Artéria Coronariana/complicações , Hipercolesterolemia/complicações , Isquemia Miocárdica/complicações , Traumatismo por Reperfusão Miocárdica/complicações , Animais , Colesterol/administração & dosagem , Doença da Artéria Coronariana/enzimologia , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/patologia , Creatina Quinase/metabolismo , Frequência Cardíaca , Hipercolesterolemia/enzimologia , Hipercolesterolemia/fisiopatologia , L-Lactato Desidrogenase/metabolismo , Masculino , Contração Miocárdica , Isquemia Miocárdica/enzimologia , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/enzimologia , Miocárdio/patologia , Perfusão , Coelhos
9.
Am J Physiol ; 269(2 Pt 2): H533-40, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7653617

RESUMO

We hypothesized that the slowly inactivating component of Na+ current, which is an integral part of the Na+ window current, is a major pathway for Na+ loading during myocardial ischemia. The putative protective effects of tetrodotoxin (TTX) and R-56865, at concentrations that selectively blocked the Na+ window current, as assessed by action potential plateau shortening without affecting maximum upstroke velocity (Vmax), were examined in isolated Langendorff-perfused guinea pig hearts subjected to 50 min of normothermic global ischemia and 60 min of reperfusion. In papillary muscles, TTX reduced action potential duration at > or = 10 nM but reduced Vmax only at > or = 1 microM. R-56865 (10 nM-10 microM) failed to affect Vmax but concentration dependently reduced action potential duration. Ischemia-induced cardiac dysfunction, including increases in left ventricular end-diastolic pressure and lactate dehydrogenase and creatine phosphokinase release at reperfusion, was attenuated by TTX and R-56865 (0.1-320 nM). Ischemic contracture (increase in left ventricular end-diastolic pressure) was abolished by drug concentrations as low as 1 nM, whereas higher concentrations (> 10 nM) of TTX and R-56865 were required to restore systolic function at reperfusion. TTX and R-56865 had little or no effect on hemodynamic variables. Evidence is provided of pronounced and direct cardioprotective effects of low concentrations of R-56865 and TTX in cardiac muscle during ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Contração Miocárdica/efeitos dos fármacos , Isquemia Miocárdica/fisiopatologia , Sódio/antagonistas & inibidores , Sódio/fisiologia , Tetrodotoxina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Benzotiazóis , Fenômenos Biomecânicos , Condutividade Elétrica , Cobaias , Coração/efeitos dos fármacos , Coração/fisiopatologia , Técnicas In Vitro , Masculino , Reperfusão Miocárdica , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/fisiopatologia , Piperidinas/farmacologia , Valores de Referência , Tiazóis/farmacologia
10.
Br J Haematol ; 89(1): 191-5, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7833262

RESUMO

Double hemibody irradiation (DHBI) is an alternative treatment of stage III multiple myeloma (MM) in patients aged over 55 years. Toxic side-effects such as myelosuppression are a severe limiting factor to its use. We performed DHBI associated with human recombinant granulocyte-macrophage colony stimulating factor (hrGM-CSF) as support therapy in 10 patients with stage III MM to improve the tolerance to this treatment. Ten patients received subcutaneously 5 micrograms/kg/d of hrGM-CSF during 2 weeks after each course of hemibody irradiation. All these patients had stage III MM: eight previously received chemotherapy, six of them were regarded as patients with refractory MM and two with relapse. Two patients received DHBI as first-line treatment. hrGM-CSF increased safety and tolerance of DHBI. GM-CSF support reduced the mean time between upper body irradiation (UBI) and lower body irradiation (LBI): 41 v 108 d in a cohort of 32 patients previously treated without growth factor support. Overall there was no lethal infection with hrGM-CSF or granulocytopenia (5.0 x 10(9)/l v 0.4 x 10(9)/l at day 15 in patients without growth factor). hrGM-CSF also reduced stomatitis grading and thrombocytopenia (90 x 10(9)/l v 45 x 10(9)/l at day 15). Furthermore, hrGM-CSF increased blood colony forming unit-granulocyte macrophage (CFU-GM) and was well tolerated in all but one patient. hrGM-CSF reduces toxic side-effects of DHBI, thus providing an effective treatment in patients with advanced and resistant MM.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Irradiação Hemicorpórea/efeitos adversos , Mieloma Múltiplo/radioterapia , Tolerância a Radiação , Idoso , Agranulocitose/prevenção & controle , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/efeitos adversos , Células-Tronco Hematopoéticas/efeitos da radiação , Humanos , Controle de Infecções , Contagem de Leucócitos/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Proteínas Recombinantes/uso terapêutico
11.
Leuk Lymphoma ; 16(1-2): 121-4, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7696917

RESUMO

We describe a new and original therapy with total body irradiation in two separate 4 gy single courses (double hemibody irradiation) combined with GM-CSF support, 5ug/day on days 1-15 after each hemibody irradiation, for refractory patients with B-chronic lymphocytic leukemia (CLL). A complete response was observed in a patient with a B-CLL resistant to CAP and FAMP therapy. Overall tolerance was good. The major points of interest in this technique are the combination of the antitumor effect of irradiation, limited bone marrow toxicity and a potential specific anti-leukemia effect of GM-CSF.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Irradiação Hemicorpórea , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/radioterapia , Idoso , Medula Óssea/patologia , Terapia Combinada , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Masculino , Terapia de Salvação
12.
Br J Pharmacol ; 112(1): 195-9, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7913378

RESUMO

1. The putative direct protective effects of a series of chemically diverse alpha 1-adrenoceptor antagonists against veratrine alkaloid-induced tetanic contractures in rat isolated left atria have been investigated. 2. Atria were mounted in organ baths containing normal, oxygenated physiological salt solution (20 ml, pH 7.4), for isometric tension recording. Atria were electrically driven at 4 Hz and were maintained at 34 degrees C. Veratrine (100 micrograms ml-1) was applied to the atria to elicit tetanic (diastolic) contracture. 3. Concentration-dependent protective effects against veratrine-contractures, in the absence of negative inotropic responses, were observed with the quinazoline congeners, prazosin and doxazosin and with the benzodioxane-related compounds, WB 4101 and its thio analogue, benoxathian. IC50 concentrations and apparent Hill coefficients of all four drugs ranged from 0.27 to 0.93 microM, and from 0.86 to 1.09, respectively, and are consistent with interaction at a single site. 4. In contrast, no protective activity versus veratrine-contractures was observed with corynanthine, 5-methyl-urapidil, phenoxybenzamine, phentolamine or chloroethylclonidine (10 microM). 5. Contractures were prevented by prazosin at concentrations 2-3 log units higher than those which antagonized methoxamine-evoked inotropic responses. In addition, concomitant alpha 1-adrenoceptor occupancy by high concentrations of methoxamine (100 microM), phentolamine (10 microM, inactive per se in preventing contracture), or both drugs together, failed, in each case, to modify significantly the protective effects of prazosin or WB 4101 against veratrine-contractures. 6. Our findings demonstrate that alpha 1-adrenoceptor antagonists which prevent veratrine-contractures belong to specific chemical classes of the quinazoline- and benzodioxane-type. The mechanism by which these drugs afford protection is apparently independent of an interaction with defined alpha 1-adrenoceptors.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/química , Antagonistas Adrenérgicos alfa/farmacologia , Contração Miocárdica/efeitos dos fármacos , Veratrina/antagonistas & inibidores , Animais , Estimulação Elétrica , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Masculino , Metoxamina/antagonistas & inibidores , Metoxamina/farmacologia , Ratos , Ratos Wistar , Estimulação Química , Veratrina/farmacologia
13.
Int J Radiat Oncol Biol Phys ; 28(2): 343-7, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8276648

RESUMO

PURPOSE: To assess the influence of instantaneous total-body irradiation dose rate in hematological malignancies, we randomized 157 patients according to different instantaneous dose rates. METHODS AND MATERIALS: Between December 10, 1986 and December 31, 1989 157 patients have undergone a total-body irradiation before bone-marrow transplantation according to two different techniques: either in one fraction (1000 cGy given to the midplane at the level of L4, and 800 cGy to the lungs) or in six fractions (1200 cGy over 3 consecutive days to the midplane at the level of L4, and 900 cGy to the lungs). Patients were randomized according to two instantaneous dose rates, called LOW and HIGH, in single-dose (6 vs. 15 cGy/min) and fractionated (3 vs. 6 cGy/min) TBI groups; there were 77 cases for the LOW and 80 for the HIGH groups, with 57 patients receiving single-dose (28 LOW, 29 HIGH) and 100 patients receiving fractionated total-body irradiation (49 LOW, 51 HIGH). RESULTS: As of July 1992, 16 (10%) of 157 patients developed cataracts after 17 to 46 months, with an estimated incidence of 23% at 5 years. Four (5%) of 77 patients in the LOW group, 12 (15%) of 80 patients in the HIGH group developed cataracts, with 5-year estimated incidences of 12% and 34%, respectively (p = 0.03). Ten (18%) of 57 patients in the single-dose group, and 6 (6%) of 100 patients in the fractionated group developed cataracts, with 5-year estimated incidences of 39% and 13%, respectively (p = 0.02). When the subgroups were considered, in the single-dose group, 3 (11%) of 28 LOW patients, and 7 (24%) of 29 HIGH patients developed cataracts, with 5-year estimated incidences of 24% and 53%, respectively; in the fractionated group, 1 (2%) of 49 LOW patients, and 5 (10%) of 51 HIGH patients developed cataracts, with 5-year estimated incidences of 4% and 22%, respectively (single-dose LOW vs. single-dose HIGH vs. fractionated LOW vs. fractionated HIGH, p = 0.006). There was no statistically significant difference in terms of 5-year estimated cataract incidence between the patients receiving steroids and those not (30% vs. 25%, p = 0.22). Multivariate analyses revealed that the instantaneous dose rate was the only independent factor influencing the cataractogenesis (p = 0.04). CONCLUSION: We conclude that the total-body irradiation regimen (instantaneous dose rate and/or fractionation) may have an influence on the development of cataracts following bone-marrow transplantation.


Assuntos
Catarata/etiologia , Irradiação Corporal Total/efeitos adversos , Adolescente , Corticosteroides/efeitos adversos , Adulto , Transplante de Medula Óssea , Criança , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica
14.
Cancer ; 69(11): 2853-65, 1992 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1571917

RESUMO

One hundred fifty-seven patients referred to the Department of Radiation Oncology of the Hôpital Tenon, Paris, France, between December 10, 1986 and December 31, 1989 for total-body irradiation (TBI) were treated according to the following two techniques: (1) either in one fraction (1000 cGy administered to the midplane at L4 and 800 cGy to the lungs) or (2) in six fractions (1200 cGy on 3 consecutive days to the midplane at L4 and 900 cGy to the lungs). The patients were randomized according to two instantaneous dose rates, called LOW and HIGH, in single-dose (6 versus 15 cGy/min) and hexafractionated (3 versus 6 cGy/min) TBI groups. There were 77 patients in the LOW group and 80 in the HIGH group, with 57 patients receiving single-dose TBI (28 LOW and 29 HIGH) and 100 patients receiving fractionated-dose TBI (49 LOW and 51 HIGH). In March 1991, the 4-year relapse-free and overall survival rates were 58.4% and 52.1%, respectively. The 4-year relapse-free survival and survival rates were 54.9% and 50.7% in the LOW group; 61.9% and 53.5% in the HIGH group (P = 0.69 and 0.82, respectively); 60.3% and 50.4% in the single-dose group; and 57.9% and 53.3% in the fractionated group (P = 0.65 and 0.78, respectively). There was no difference in the incidence of graft versus host disease, interstitial pneumonitis, or venoocclusive disease either between the LOW and the HIGH groups or between the single-dose and fractionated-dose TBI groups. The 4-year estimated cataract incidence was significantly higher in the single-dose HIGH instantaneous dose rate group than in the LOW instantaneous dose rate TBI group (P = 0.049). Multivariate analyses showed that instantaneous dose rate and fractionation do not influence the relapse-free and overall survival rates or the incidence of interstitial pneumonitis.


Assuntos
Transplante de Medula Óssea , Irradiação Corporal Total/efeitos adversos , Adolescente , Adulto , Transplante de Medula Óssea/mortalidade , Catarata/epidemiologia , Criança , Ciclofosfamida/administração & dosagem , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fibrose Pulmonar/epidemiologia , Doses de Radiação , Recidiva , Taxa de Sobrevida , Resultado do Tratamento , Doenças Vasculares/epidemiologia , Veias
15.
Cancer ; 65(2): 322-6, 1990 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2295054

RESUMO

From January 1979 to December 1987, 35 cases of primary central nervous system lymphoma (CNS-L) were treated. We recently reviewed these cases focusing on treatment results, treatment modalities, and radiotherapy (RT) or chemotherapy-radiotherapy (CT-RT). Variables such as age, risk factors, presenting symptoms, and histologic condition (all were high-grade or intermediate-grade non-Hodgkin's lymphomas [NHL]) and radiologic data were similar to those of series reported previously. The median survival time was 36 months (+/- 0.2 months) and the disease-free survival (DFS) time was 16 months (+/- 0.12 months). Twelve of 32 patients evaluable for treatment results experienced a recurrence (all but one occurred in the CNS). The DFS rate was 70% for the CT-RT group and 50% for the RT group (median follow-up time, 24 months). Therapeutic results in CNS-L are discussed with special emphasis on a putative role of CT in the management of this rare type of tumor.


Assuntos
Neoplasias Encefálicas/terapia , Linfoma/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/mortalidade , Terapia Combinada , Feminino , Humanos , Linfoma/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Fatores de Risco , Análise de Sobrevida
16.
Int J Radiat Oncol Biol Phys ; 17(6): 1141-51, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2599902

RESUMO

UNLABELLED: From 1972 to 1985, 260 cases of anal canal epidermoid carcinoma were irradiated. Eighteen cases treated for palliation were excluded from the study; 242 (93%) were treated with curative intent. The sex ratio was 1/5.5; mean age was 66 years. HISTOLOGY: 60.3% were well differentiated epidermoid carcinoma; 31.0% moderately differentiated and 8.7%, cloacogenic cases. Staging: T1: 11.5%; T2: 16.1%; T3a: 17%; T3b: 33.5%; and T4: 21.9%. Abnormal inguinal nodes were present in 15.3% of cases. Crude overall survival (Kaplan-Meier) for the 242 cases is 86.4% at 1 year, 63.9% at 3 years, 51.2% at 5 years, and 30.8% at 10 years. Radiation therapy was the sole treatment for 193 cases. No chemotherapy was given. Patients were irradiated by external beam. They received a first course of X rays (mostly 18 MV, some 6 MV) 40 to 45 Gy (box technique) over 4 to 5 weeks in the pelvis. Age and size of tumor were considered when deciding on the target volume. After a rest period of 4 to 6 weeks, a second course of 15 to 20 Gy in 2 weeks was given through a perineal field by electron-beam of suitable energy. The mean total dose was 60.56 Gy and median was 62.5 Gy; the mean overall treatment duration was 85.3 days (median 82 days) and the mean Time Dose Factor including decay factor was 98.96. In this group, 5-year determinate survival was: T1-T2, 84.5%; T3a, 74.8%; T3b, 64.9%; T4, 58.9%. In 147/193 patients (76.2%) local control was achieved. The overall anal conservation rate was 62.6%. In 106 cases (55%), the anus had maintained normal function. The 5-year survival rate by N was 73.3% in the absence of inguinal nodes (169 cases) and 36.1% if such nodes were present. There was no significant difference in survival rate according to histological type. In the second group, receiving radiation therapy plus surgery, 33/49 cases (T3b-T4) were irradiated before surgery (median dose 40.5 Gy). Post operative radiation therapy was administered in 16 cases (T3b-T4) (median dose 49.6 Gy). The 5-year determinate survival is 53.2% for T3b and 79% for T4. According to the log-rank test, there was no significant difference between survival with radiation therapy alone and radiation therapy plus surgery. Multivariate analysis of the whole group indicated that T stage is the only predictive variable.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Neoplasias do Ânus/radioterapia , Carcinoma de Células Escamosas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Ânus/mortalidade , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/radioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
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