Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Curr Med Chem ; 19(7): 972-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22214463

RESUMO

Glioblastoma multiforme (GBM) is a common and malignant primary brain tumor arising from glial precursors the survival of which is estimated to be about 14 months after diagnosis despite current standard care with radiotherapy, surgery, and chemotherapies. Therapeutic approaches were greatly improved in the last years; however, GBM still represents the most lethal subtype of glioma. Actually, it has been estimated that only about 3.4% of patients will survive at the most five years when obtaining the best outcome from treatment; however, this depends on tumor resistance, which is generally related to repairing radiation injury, and self- improving cell growth repair and survival. All GBMs recur after initial therapy, limiting patients � survival at 20-25% within 1 year after diagnosis of recurrent disease. Moreover, for recurrent GBM response rates are less than 10% (ranging from 5% to 9%), and progression free survival at 6-month (PFS-6) rates ranges between 9% and 28% (median 15%). The development of targeted therapy based on tumor vascular blockade led to the approval of bevacizumab for recurrent or progressive glioblastoma, since it was proven that this offers a new opportunity for patients suffering from this malignancy. Bevacizumab is a recombinant antivascular monoclonal antibody binding to circulating Vascular Endothelial Growth Factor (VEGF) preventing this cytokine from reaching its receptors (VEGFR1 and VEGFR2) on endothelium, resulting in an inhibition of cells proliferation and vessels sprouting. The aim of this review is to address bevacizumab mode of action in malignant gliomas and provide a summary on currently available data on efficacy and safety.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Bevacizumab , Humanos , Segurança , Resultado do Tratamento
2.
Eur J Cancer ; 38 Suppl 4: S50-3, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11858965

RESUMO

The EORTC Chronotherapy Group (CTG) stemmed from the International Organisation for Cancer Chronotherapy (IOCC) in 1996. The IOCC was first to initiate large scale multicentre international chronotherapy trials, for the purpose of investigating the relevance of chronomodulated or timed administration of cancer therapy based on biological rhythms. Programmable pumps for cytotoxic chronodelivery and actigraph devices to monitor circadian rhythm alterations linked to cancer were also developed. The unique expertise of the IOCC with regard to cancer chronotherapy furthered its development within the EORTC. The EORTC offers broad expertise in clinical cancer research and opportunities for scientific recognition, intergroup collaborations and translational research. Over the past 5 years, the EORTC CTG has grown from 16 to 48 centres in 12 different countries. It is currently conducting seven multicentre chronotherapy trials which test the relevance of adapting cancer treatment delivery to circadian rhythms. The group aims at developing multiple collaborations to establish a chronotherapy network involving institutions with expertise ranging from experimental chronobiology to new drug testing, disease-specific management and quality of life or survival issues.


Assuntos
Antineoplásicos/administração & dosagem , Cronoterapia/métodos , Ritmo Circadiano , Ensaios Clínicos como Assunto/métodos , Esquema de Medicação , Europa (Continente) , Humanos , Agências Internacionais , Oncologia
3.
Eur J Cancer ; 38 Suppl 4: S138-41, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11858980

RESUMO

The EORTC Soft Tissue Sarcoma Group was founded 25 years ago and has since developed into one of the leading cooperative groups in the research of sarcomas and has members from 40 institutions from 13 countries. The activities of the group have primarily been within the areas of standards for local as well as systemic treatment strategies, new drug development and quality control procedures. The group has a extensive quality control programme involving a strict membership policy, central review of the responses, central review of pathology, use a systemic therapy check-list and on-site monitoring of studies. A large database with over 2500 patients included in EORTC STBSG chemotherapy trials has been developed. So far, the STBSG has conducted more than 40 clinical trials accruing more than 250 patients per year, some of which has been performed in collaboration with other prestigious groups.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Quimioterapia Adjuvante , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Europa (Continente) , Humanos , Agências Internacionais , Oncologia , Osteossarcoma/tratamento farmacológico
4.
Lancet ; 358(9291): 1421-3, 2001 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11705489

RESUMO

BACKGROUND: Gastrointestinal stromal tumours (GISTs) are rare tumours of the gastrointestinal tract characterised by cell-surface expression of the tyrosine kinase KIT (CD117). No effective systemic treatment is available. Imatinib (STI571) inhibits a similar tyrosine kinase, BCR-ABL, leading to responses in chronic myeloid leukaemia, and has also been shown to inhibit KIT. We did a phase I study to identify the dose-limiting toxic effects of imatinib in patients with advanced soft tissue sarcomas including GISTs. METHODS: 40 patients (of whom 36 had GISTs) received imatinib at doses of 400 mg once daily, 300 mg twice daily, 400 mg twice daily, or 500 mg twice daily. Toxic effects and haematological, biochemical, and radiological measurements were assessed during 8 weeks of follow-up. 18Fluorodeoxy-glucose positron-emission tomography (PET) was used for response assessment in one centre. FINDINGS: Five patients on 500 mg imatinib twice daily had dose-limiting toxic effects (severe nausea, vomiting, oedema, or rash). Inhibition of tumour growth was seen in all but four patients with GISTs, resulting in 19 confirmed partial responses and six as yet unconfirmed partial responses or more than 20% regressions. 24 of 27 clinically symptomatic patients showed improvement, and 29 of 36 were still on treatment after more than 9 months. PET scan responses predicted subsequent computed tomography responses. INTERPRETATION: Imatinib at a dose of 400 mg twice daily is well tolerated during the first 8 weeks, side-effects diminish with continuing treatment, and it has significant activity in patients with advanced GISTs. Our results provide evidence of a role for KIT in GISTs, and show the potential for the development of anticancer drugs based on specific molecular abnormalities present in cancers.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Gastrointestinais/tratamento farmacológico , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Benzamidas , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Fluordesoxiglucose F18 , Neoplasias Gastrointestinais/diagnóstico por imagem , Neoplasias Gastrointestinais/secundário , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Pirimidinas/efeitos adversos , Cintilografia , Resultado do Tratamento
5.
Eur J Cancer ; 37(7): 870-7, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11313175

RESUMO

CAELYX/DOXIL, pegylated liposomal doxorubicin, has shown antitumour activity and reduced toxicity compared with standard doxorubicin in other tumour types. In this prospective randomised trial, 94 eligible patients with advanced soft-tissue sarcoma (STS) were treated, 50 with CAELYX (50 mg/m(2) by a 1 h intravenous (i.v.) infusion every 4 weeks) and 44 with doxorubicin (75 mg/m(2) by an i.v. bolus every 3 weeks). Histological subtypes were evenly matched, 33% were leiomyosarcoma (CAELYX: 18; doxorubicin: 13). Primary disease sites were well matched. CAELYX was significantly less myelosuppressive, only 3 (6%) patients had grade 3 and 4 neutropenia, versus 33 (77%) on doxorubicin; febrile neutropenia occurred in 7 (16%) patients given doxorubicin, but only 1 (2%) given CAELYX. 37 (86%) patients on doxorubicin had grade 2-3 alopecia, but only 3 (6%) on CAELYX, and the major toxicity with CAELYX was to the skin. Palmar-plantar erythrodysesthesia with CAELYX was grade 1: 4 (8%) patients, grade 2: 11 (22%) patients, grade 3: 9 (18%) patients and grade 4: 1 (2%) patient. Other non-haematological grade 3 and 4 toxicities were rare. Confirmed responses were observed with both agents: CAELYX: complete response (CR) 1 (uterine), partial response (PR) 4 (response rate (RR) 10%); and doxorubicin: CR 1, PR 3 (RR of 9%); with the best response being stable disease (NC) in 16 and 18 patients, respectively. The reason for the low response rate is unknown, but it may be due partly to a high proportion of gastrointestinal stromal tumours. In conclusion, CAELYX has equivalent activity to doxorubicin in STS with an improved toxicity profile and should be considered for further investigation in combination with other agents such as ifosfamide.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Doxorrubicina/uso terapêutico , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Intervalo Livre de Doença , Portadores de Fármacos , Feminino , Humanos , Lipossomos , Masculino , Pessoa de Meia-Idade , Sarcoma/secundário , Neoplasias de Tecidos Moles/secundário , Resultado do Tratamento
6.
Eur J Pharmacol ; 317(2-3): 239-45, 1996 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-8997606

RESUMO

The effects of repeated administration of the selective adenosine A1 receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA), the selective adenosine A2 receptor agonist 2-hexynyl-5'-N-ethylcarboxamidoadenosine (2HE-NECA), the non-selective adenosine A1/A2 receptor agonist 5'-N-ethylcarboxamidoadenosine (NECA), the selective adenosine A1 receptor antagonist 8-cyclopentyl-1,3 dipropylxanthine (DPCPX) and the selective adenosine A2 receptor antagonist 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-(4,3-e)1,2,4-triazolo(1,5 -c)pyrimidine (SCH 58261) on the anticonvulsant activity of 3-(2-carboxypiperazine-4y)propenyl-1-phosphonic acid (CPPene), a selective N-methyl-D-aspartate receptor antagonist, were evaluated in audiogenic sensible dilute brown agouti mice DBA/2J (DBA/2). Mice were treated intraperitoneally twice daily for 7 days with CCPA 0.11 mg/kg, 2HE-NECA 0.056 mg/kg, NECA 0.11 mg/kg, DPCPX 0.5 mg/kg and SCH 58261 0.5 mg/kg followed by 2 vehicle injections (the wash-out period of 1 day) and subsequently CPPene was administered intracerebroventricularly. Audiogenic seizures were delivered 30 min after CPPene administration. Repeated treatment with CCPA significantly reduced the anticonvulsant properties of CPPene against audiogenic seizures. A weak and not significant reduction of anticonvulsant effects of CPPene was observed following repeated administration of NECA, whilst the repeated administration of 2HE-NECA did not decrease the antiseizure activity of CPPene. Conversely, repeated administration of DPCPX markedly potentiated the anticonvulsant properties of CPPene, whilst the repeated treatment with SCH 58261 did not increase the anticonvulsant activity of CPPene. The present results indicate that repeated treatment with CPPA, a selective adenosine A1 receptor agonist, decreases the anticonvulsant properties of CPPene, whilst the repeated administration of DPCPX, a selective adenosine A1 receptor antagonist, potentiates the anticonvulsant effects of CPPene. The compounds acting as selective agonists or antagonists of adenosine A2 receptors do not affect the antiseizure activity of CPPene. In conclusion, the repeated interaction of agonists or antagonists with adenosine A1 receptors seems to induce changes on anticonvulsant activity of CPPene, whereas drugs acting at adenosine A2 receptors do not.


Assuntos
Anticonvulsivantes/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Piperazinas/farmacologia , Agonistas do Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Estimulação Acústica , Adenosina/análogos & derivados , Adenosina/farmacologia , Adenosina-5'-(N-etilcarboxamida) , Animais , Anticonvulsivantes/antagonistas & inibidores , Anticonvulsivantes/farmacocinética , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacocinética , Injeções Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos DBA , Piperazinas/antagonistas & inibidores , Piperazinas/farmacocinética , Pirimidinas/farmacologia , Triazóis/farmacologia , Xantinas/farmacologia
7.
Eur J Pharmacol ; 286(2): 147-54, 1995 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-8605951

RESUMO

Chronic administration of propionyl-l-carnitine has been recently shown to correct hypertrophy related abnormalities in muscle mechanics. Accordingly, this study investigated whether the drug would similarly improve cardiac dynamics in rats with pressure overload. Enalapril was used for comparison. Drugs were administered in the drinking water for 3 weeks to Wistar Kyoto rats with a 2 week abdominal aortic constriction. Cardiac function was studied under urethane anaesthesia in basal conditions, during increase in preload, and during increase in afterload. Basal cardiac function was comparable in pressure-overloaded and sham-operated animals. Neither propionyl-l-carnitine nor enalapril affected the basal performance. Compared to sham-operated animals, untreated pressure-overloaded rats showed an impaired cardiac response (cardiac output, stroke volume) to preload increase induced by saline i.v. infusion. Propionyl-l-carnitine dose dependently improved cardiac function in the range 30-180 mg/kg, without affecting cardiac hypertrophic growth. Enalapril (3 mg/kg) reduced cardiac hypertrophy and improved cardiac function. The two effects were unrelated. The afterload increase by total aortic occlusion evidenced a reduction in the left ventricle pressure generating capacity of hypertrophied hearts. Propionyl-l-carnitine did not modify this parameter, while enalapril afforded a significant improvement. Results show that propionyl-l-carnitine significantly improves in vivo cardiac dynamics under conditions of increased energy demand. The effect is not due to inotropic efficacy, but presumably to increased cardiac efficiency.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Cardiotônicos/farmacologia , Carnitina/análogos & derivados , Enalapril/farmacologia , Coração/efeitos dos fármacos , Animais , Carnitina/farmacologia , Hemodinâmica/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos WKY
8.
J Pharmacol Exp Ther ; 264(1): 1-5, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8380855

RESUMO

Clone N1E-115 cells have specific, high-affinity binding sites for neurotensin (NT). These receptors mediate formation of cyclic GMP and other second messengers. We studied the effects of extended exposure of cells to [D-Lys8]NT(8-13) (NT2), a peptidase-resistant NT analog, on NT's ability to stimulate cyclic GMP synthesis and to bind [3H]NT to its sites on these cells. When intact N1E-115 cells were preincubated with NT2 (1 microM) for various times (15 min to 12 hr) at 37 degrees C, maximal desensitization and binding site (Bmax) loss occurred after only 15 min. Receptor affinity for [3H]NT did not change. At 0 degrees C NT2 for 15 min caused no down-regulation. After 15 min of preincubation with NT2 at 37 degrees C, the recovery of receptor binding and function after a 10 to 20 min lag-time was rapid (T1/2 = 15 min and 19 min, for binding and cyclic GMP response, respectively). After 12 hr of NT2 preincubation, it was slow (T1/2 = 212 min). Incubation of cells with cycloheximide (70 microM) for 5 hr after their exposure to NT2 for 15 min did not change the rate or extent of recovery of NT Bmax. However, cycloheximide did decrease the recovery of NT Bmax after exposure of cells to NT2 for 12 hr. Cycloheximide alone did not change NT Bmax. These data suggest that this decrease of NT receptor binding after short (15 min) and long (12 hr) exposure times to agonist involves two consecutive steps: intracellular sequestration of recyclable NT receptors, followed by receptor degradation causing true down-regulation.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Neuroblastoma/fisiopatologia , Neurotensina/análogos & derivados , Neurotensina/fisiologia , Fragmentos de Peptídeos/farmacologia , Receptores de Neurotransmissores/efeitos dos fármacos , Animais , Sítios de Ligação , Cicloeximida/farmacologia , Camundongos , Proteínas de Neoplasias/biossíntese , Neuroblastoma/ultraestrutura , Neurotensina/farmacologia , Receptores de Neurotensina , Receptores de Neurotransmissores/fisiologia , Fatores de Tempo , Células Tumorais Cultivadas/efeitos dos fármacos
9.
Fundam Clin Pharmacol ; 5(6): 503-11, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1955195

RESUMO

The role of nitric oxide (NO) in the genesis of motor and electrocortical seizures elicited by administration of excitatory amino acid agonists into the deep prepiriform cortex (DPC) has been evaluated. Motor and electrocortical seizures occurred in rats receiving unilateral microinjections into the DPC of either N-methyl-D-aspartate (NMDA, 5 and 10 nmol) or kainate (KA, 100 pmol). The selective NMDA receptor antagonist 2-amino-7-phosphonoheptanoate (APH), when microinjected into DPC, prevented the development of seizures induced by both NMDA and KA injected in the same site. In addition, methylene blue (20 nmol, which prevents activation of soluble guanylate cyclase) or NG-monomethyl-L-arginine (NMMA, 40 nmol; a specific inhibitor of nitric oxide synthesis), when microinjected into DPC 15 min prior to either NMDA or KA, significantly protected against seizures elicited by both excitatory amino acid agonists. These data confirm the role of excitatory amino acid transmission in the genesis of seizures elicited from the deep prepiriform cortex. They further suggest that activation of excitatory amino acid receptors within the DPC leads to the release of a substance which shares properties with EDRF/NO and contributes to the genesis of seizure activity in this area.


Assuntos
Ácido Caínico/farmacologia , N-Metilaspartato/farmacologia , Óxido Nítrico/metabolismo , Convulsões/induzido quimicamente , Lobo Temporal/efeitos dos fármacos , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Estimulação Elétrica , Eletroencefalografia , Masculino , Azul de Metileno/farmacologia , N-Metilaspartato/administração & dosagem , Ratos , Ratos Endogâmicos , Lobo Temporal/metabolismo , ômega-N-Metilarginina
10.
Neuropharmacology ; 28(1): 37-42, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2927578

RESUMO

The cardiovascular response to the unilateral injection of clonidine into the nucleus tractus solitarii in old compared to young rats was evaluated. In 3-month old rats clonidine (0.25, 0.5 and 1 microgram) injected into the nucleus tractus solitarii in anaesthetized rats produced a significant fall in blood pressure (BP) and a significant decrease in heart rate (HR). In contrast, in 12 month old rats the maximum fall in blood pressure and heart rate was significantly less than in young animals. In addition, in older rats (24 month old) clonidine, at the same or larger doses given into the nucleus tractus solitarii did not produce any significant change in the cardiovascular parameters studied. In conclusion, the present experiments provide evidence that during ageing there is a progressive decrease in the cardiovascular response to alpha 2-adrenoceptor stimulation in the nucleus tractus solitarii. In addition, it is conceivable that such a decrease and subsequently the lack in response may be related to a progressive decrease in the number and/or affinity of the specific alpha 2-adrenoceptor binding sites at this level.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Clonidina/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Animais , Encéfalo , Clonidina/administração & dosagem , Infusões Parenterais , Masculino , Ratos , Ratos Endogâmicos
11.
J Pharmacol Exp Ther ; 240(1): 288-93, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3806390

RESUMO

In pentobarbital-anesthetized dogs with decentralized adrenal glands, sinoaortic baroreceptor deafferentation produced an increase in mean aortic blood pressure which reached a maximum (42 +/- 5 mm Hg, n = 6) within 5 min and then waned entirely within the subsequent 25 min. In contrast, in sham-operated dogs, the maximal pressor response due to deafferentation was of greater magnitude (63 +/- 6 mm Hg, n = 8) and of much longer duration (44 +/- 4 mm Hg, 60 min after deafferentation). Heart rate was only augmented slightly in both preparations. A marked elevation of epinephrine plasma concentration occurred 5 min after deafferentation and the magnitude of this effect was 8 times greater in dogs with innervated than denervated adrenal glands. Norepinephrine plasma concentration increased moderately and similarly in the two preparations. Administration of pergolide (30.0 micrograms/kg i.v.) 15 min before undertaking the deafferentation procedure induced a small, short-lasting increase in blood pressure and a small fall in heart rate in dogs in which the innervation to the adrenal glands was left either intact (sham-operated) or removed surgically. In dogs with adrenal gland denervated, pergolide blocked entirely the pressor response and the small elevation in plasma concentration of catecholamines evoked by sinoaortic deafferentation in the matched, saline-pretreated group. However, in sham-operated dogs (intact adrenal innervation), pergolide reduced partially (by 41%) the increase in blood pressure and plasma epinephrine concentration caused by deafferentation. The decrease in heart rate, produced by pergolide, was abolished by deafferentation in sham-operated and adrenal decentralized dogs.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Glândulas Suprarrenais/fisiologia , Vias Aferentes/fisiologia , Sistema Cardiovascular/efeitos dos fármacos , Pergolida/farmacologia , Seio Aórtico/inervação , Animais , Pressão Sanguínea/efeitos dos fármacos , Cães , Epinefrina/sangue , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Sulpirida/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...