Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Eur J Clin Pharmacol ; 77(12): 1861-1873, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34245336

RESUMO

AIMS: To describe the sources of interindividual variability of bevacizumab and trastuzumab pharmacokinetics in early-stage breast cancer, and to study the relationship between exposure and both early clinical response and specific adverse events. PATIENTS AND METHODS: Patients (n = 86) received 6 cycles of docetaxel + trastuzumab. Early tumour response was assessed by determination of the maximum standard uptake value (SUVmax) variation (ΔSUVmax) after 1 cycle using [18F]-fluorodeoxyglucose (FDG) PET. Early poor responders (ΔSUVmax < 70%) also received bevacizumab from cycle 3 to cycle 6. Sources of interindividual variability in pharmacokinetics of both antibodies were studied by population compartment modelling. Exposure as assessed by area under the concentration-versus-time curve (AUC) was compared between responders and non-responders and between patients experiencing specific adverse events or not. RESULTS: A two-compartment model described the pharmacokinetics of both antibodies satisfactorily. Their central volume of distributions (Vc) increased with body surface area and their elimination half-lives were shorter (~14 days) than previously reported (~26-28 days). There was a time-dependent increase in trastuzumab Vc, positively correlated to baseline SUVmax. Bevacizumab elimination rate (k10) was positively correlated with ΔSUVmax measured at the end of the first cycle. Bevacizumab had no significantly influence on trastuzumab pharmacokinetics. No relationship between exposure and clinical response or occurrence of adverse events was found. CONCLUSION: Tumour uptake as assessed by SUVmax influences the pharmacokinetics of bevacizumab and trastuzumab. In early-stage breast cancer, elimination half-lives of these therapeutic monoclonal antibodies may be shorter than those previously reported in more advanced disease.


Assuntos
Antineoplásicos Imunológicos/farmacocinética , Bevacizumab/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Trastuzumab/farmacocinética , Adulto , Idoso , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Bevacizumab/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Docetaxel/uso terapêutico , Interações Medicamentosas , Feminino , Meia-Vida , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , Estadiamento de Neoplasias , Receptor ErbB-2/genética , Trastuzumab/uso terapêutico
2.
Clin Exp Dermatol ; 42(4): 413-415, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28397288

RESUMO

Levamisole (an increasingly frequent contaminant of cocaine) can cause antineutrophil cytoplasmic antibody-associated vasculitis. Dermatologists should consider a diagnosis of cocaine/levamisole-associated cutaneous vasculopathy syndrome in cases of purpura of the ears and/or extensive retiform purpura in drug users. We report a case of particularly severe levamisole-induced necrotic purpura and immunological abnormalities in a 40-year-old woman.

4.
Skeletal Radiol ; 41(9): 1141-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22318350

RESUMO

BACKGROUND: Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy. OBJECTIVE: To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment. MATERIALS AND METHODS: This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 - ADC1 and ADC3 - ADC1), and their variation (ADC2 - ADC1/ADC1 and ADC3 - ADC1/ADC1) were calculated for each of these three time points. RESULTS: Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 - ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups. CONCLUSION: DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/patologia , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Projetos Piloto , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
5.
J Exp Med ; 189(5): 779-86, 1999 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10049941

RESUMO

Contact hypersensitivity (CHS) is a T cell-mediated skin inflammation induced by epicutaneous exposure to haptens in sensitized individuals. We have previously reported that CHS to dinitrofluorobenzene in mice is mediated by major histocompatibility complex (MHC) class I-restricted CD8(+) T cells. In this study, we show that CD8(+) T cells mediate the skin inflammation through their cytotoxic activity. The contribution of specific cytotoxic T lymphocytes (CTLs) to the CHS reaction was examined both in vivo and in vitro, using mice deficient in perforin and/or Fas/Fas ligand (FasL) pathways involved in cytotoxicity. Mice double deficient in perforin and FasL were able to develop hapten-specific CD8(+) T cells in the lymphoid organs but did not show CHS reaction. However, they did not generate hapten-specific CTLs, demonstrating that the CHS reaction is dependent on cytotoxic activity. In contrast, Fas-deficient lpr mice, FasL-deficient gld mice, and perforin-deficient mice developed a normal CHS reaction and were able to generate hapten-specific CTLs, suggesting that CHS requires either the Fas/FasL or the perforin pathway. This was confirmed by in vitro studies showing that the hapten-specific CTL activity was exclusively mediated by MHC class I-restricted CD8(+) T cells which could use either the perforin or the Fas/FasL pathway for their lytic activity. Thus, cytotoxic CD8(+) T cells, commonly implicated in the host defence against tumors and viral infections, could also mediate harmful delayed-type hypersensitivity reactions.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Dermatite de Contato/imunologia , Animais , Movimento Celular , Dermatite de Contato/etiologia , Dermatite de Contato/genética , Dinitrofluorbenzeno/imunologia , Proteína Ligante Fas , Haptenos , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Interferon gama/biossíntese , Tecido Linfoide/imunologia , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Perforina , Proteínas Citotóxicas Formadoras de Poros , Pele/imunologia , Receptor fas/genética
6.
Eur Radiol ; 19(3): 679-86, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18839180

RESUMO

To evaluate the efficiency of laser thermocoagulation under computed tomography (CT) guidance in the treatment of osteoid osteoma within a strictly pediatric group. Twenty-five patients aged 4 to 17 years were treated under CT by laser thermocoagulation. The nidus measured on average 10.1 mm. Pain relief was the main item for evaluation of the effectiveness of our treatment. Follow-up ranged from 3 months to 61 months (mean, 26 months). Technical success was achieved in 100%. Thermocoagulation proved to be initially effective in 24 of 25 children (96%) and had a positive long-term effect in 23 of 25 children (92%). We had four minor complications and one severe complication (partial osteonecrosis of the talus). Laser thermocoagualation is an effective treatment for osteoid osteoma in pediatric patients.


Assuntos
Neoplasias Ósseas/terapia , Fotocoagulação a Laser/métodos , Osteoma Osteoide/terapia , Tomografia Computadorizada por Raios X/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Dor , Estudos Prospectivos , Radiografia Intervencionista/métodos , Resultado do Tratamento
7.
J Radiol ; 90(4): 485-91, 2009 Apr.
Artigo em Francês | MEDLINE | ID: mdl-19503030

RESUMO

PURPOSE: To compare image quality and radiation exposure from pediatric thoracic spine radiographs from two systems, one using a granular structure scintillator and another using a needle structure scintillator with 40% reduction of exposure. PATIENTS AND METHODS: Randomized prospective study of 296 patients divided into 2 groups of 5 weight categories from 4 to 60 kg. Standard technique parameters are used for granular structure scintillators with dose reduction of 40% applied for needle structure scintillators based on results from a phantom study. Image quality based on detectability of 8 anatomical structures for both types of scintillators was assessed by 6 blinded radiologists. Exposure was expressed by DLP. Results underwent statistical analysis. RESULTS: Overall, image quality was superior with corresponding dose reduction between 33-46% according to weight with needle structure scintillators. For the 4 lower weight categories, image quality was identical. CONCLUSION: With image quality at least equal, new needle structure scintillator units allow a dose reduction of about 40%.


Assuntos
Doses de Radiação , Intensificação de Imagem Radiográfica , Radiografia Torácica , Contagem de Cintilação , Adolescente , Fatores Etários , Peso Corporal , Criança , Pré-Escolar , Interpretação Estatística de Dados , Humanos , Lactente , Variações Dependentes do Observador , Imagens de Fantasmas , Estudos Prospectivos , Radiografia Torácica/normas , Radiometria
8.
Neuroscience ; 156(2): 353-64, 2008 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-18691638

RESUMO

SR58611A is a selective beta(3)-adrenoceptor (Adrb3) agonist which has demonstrated antidepressant and anxiolytic properties in rodents. The present study confirmed the detection of Adrb3 mRNA transcript in rodent brain sub-regions and evaluated the effect of SR58611A on serotonergic and noradrenergic transmission in rats and mice in an attempt to elucidate the mechanism(s) underlying these properties. SR58611A (3 and 10 mg/kg, p.o.) increased the synthesis of 5-HT and tryptophan (Trp) levels in several rodent brain areas (cortex, hippocampus, hypothalamus, striatum). Moreover, SR58611A (10 mg/kg, p.o.) increased the release of 5-HT assessed by in vivo microdialysis in rat prefrontal cortex. Systemic (3 mg/kg, i.v.) or chronic administration of SR58611A (10 mg/kg, p.o.), in contrast to fluoxetine (15 mg/kg, p.o.), did not modify the activity of serotonergic neurons in the rat dorsal raphe nucleus. The increase in 5-HT synthesis induced by SR58611A was not observed in Adrb3s knockout mice, suggesting a selective involvement of Adrb3s in this effect. SR58611A (3 and 10 mg/kg, p.o.) did not modify norepinephrine synthesis and metabolism but increased its release in rat brain. Repeated administration of SR58611A (10 mg/kg, p.o.) did not modify basal norepinephrine release in rat prefrontal cortex whereas it prevented its tail-pinch stress-induced enhancement similarly to reboxetine (15 mg/kg, p.o.). Finally SR58611A increased the firing rate of noradrenergic neurons in the rat locus coeruleus following systemic (3 mg/kg, i.v.) or local (0.01 and 1 microM) but not chronic (10 mg/kg, p.o.) administration. These results suggest that the anxiolytic- and antidepressant-like activities of SR58611A involve an increase of brain serotonergic and noradrenergic neurotransmissions, triggered by activation of Adrb3s.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Encéfalo/efeitos dos fármacos , Norepinefrina/metabolismo , Serotonina/metabolismo , Tetra-Hidronaftalenos/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Inibidores da Captação Adrenérgica/farmacologia , Agonistas de Receptores Adrenérgicos beta 2 , Análise de Variância , Animais , Encéfalo/anatomia & histologia , Encéfalo/citologia , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Interações Medicamentosas , Fluoxetina/farmacologia , Masculino , Camundongos , Microdiálise , Morfolinas/farmacologia , Atividade Motora/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Reboxetina , Receptores Adrenérgicos beta 2/genética , Receptores Adrenérgicos beta 2/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Triptofano/metabolismo
9.
Diagn Interv Imaging ; 99(10): 663-668, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29853348

RESUMO

PURPOSE: To assess the capabilities of a velocity ratio>3 for the diagnosis of Budd-Chiari syndrome (BCS) in children after split liver transplantation using Doppler ultrasonography (DUS). MATERIALS AND METHODS: A total of 28 children who underwent liver transplantation using a split procedure were included. There were 11boys and 17girls with a mean age of 3.8years (range: 0.7-12years). Velocity ratio between blood velocity upstream of the anastomosis and that at the level of the inferior vena cava anastomosis was calculated. Sensitivity, specificity and accuracy of DUS for the diagnosis of BCS were estimated using a velocity ratio>3. RESULTS: Eight children (8/28; 29%) had BCS and 20 (20/28; 71%) did not have BCS using the standard of reference. A velocity ratio>3 on DUS yielded 88% sensitivity (95% CI: 53-98%), 80% specificity (95% CI: 58-92%) and 82% accuracy (95% CI: 64-92%) for the diagnosis of BCS. CONCLUSION: A velocity ratio>3 on DUS is a reliable finding for the diagnosis of BCS in children after split liver transplantation.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Síndrome de Budd-Chiari/diagnóstico por imagem , Veias Hepáticas/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Veia Cava Inferior/diagnóstico por imagem , Anastomose Cirúrgica , Síndrome de Budd-Chiari/fisiopatologia , Criança , Feminino , Veias Hepáticas/fisiopatologia , Humanos , Transplante de Fígado/métodos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Veia Cava Inferior/fisiopatologia
10.
Neuroscience ; 137(2): 555-64, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16289893

RESUMO

2-Chloro-N-S-phenyl 2S-piperidin-2-yl methyl]-3-trifluoromethyl benzamide, monohydrochloride (SSR504734) is a potent and selective inhibitor of the glycine transporter type 1, which increases central N-methyl-D aspartate glutamatergic tone. Since glutamate has been shown to play a role in the regulation of the dopaminergic system in dopamine-related disorders, such as schizophrenia, we investigated the possibility that SSR504734 may modify the basolateral amygdala-elicited stimulation of dopamine release in the nucleus accumbens via an augmentation of glutamate receptor-mediated neurotransmission. First, our data confirmed that SSR504734 is an inhibitor of GlytT1. In the nucleus accumbens of anesthetized rat, SSR504734 (10 mg/kg, i.p.) induced an increase of extracellular levels of glycine as measured by microdialysis coupled with capillary electrophoresis with laser-induced fluorescence detection. Second, the data demonstrated that SSR504734 (10 mg/kg, i.p.) enhanced the facilitatory influence of glutamatergic afferents on dopamine neurotransmission in the nucleus accumbens. Using an electrochemical technique, we measured dopamine release in the nucleus accumbens evoked by an electrical stimulation of the basolateral amygdala. SSR504734 facilitated dopamine release evoked by a 20 or a 40 Hz frequency basolateral amygdala stimulation. This facilitatory effect was dependent on glutamatergic tone, as intra-nucleus accumbens application of 6-7-dinitroquinoxaline-2,3-dione (10(-3) M) or DL-2-amino-5-phosphonopentanoic acid (10(-3) M), alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid and N-methyl-D aspartate receptors antagonists, respectively, inhibited dopamine release evoked by basolateral amygdala stimulation. Furthermore DL-2-amino-5-phosphonopentanoic acid co-administrated with SSR504734 hampered the dopamine-evoked release facilitation. These data underline the in vivo implication of the glycine uptake mechanism in the control of subcortical glutamate/dopamine interactions.


Assuntos
Benzamidas/farmacologia , Dopamina/metabolismo , Ácido Glutâmico/metabolismo , Proteínas da Membrana Plasmática de Transporte de Glicina/metabolismo , Glicina/metabolismo , Núcleo Accumbens/metabolismo , Piperidinas/farmacologia , Tonsila do Cerebelo/fisiologia , Animais , Estimulação Elétrica , Antagonistas de Aminoácidos Excitatórios/farmacologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Proteínas da Membrana Plasmática de Transporte de Glicina/antagonistas & inibidores , Masculino , Microdiálise , Vias Neurais/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/antagonistas & inibidores , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
11.
Neuroscience ; 141(3): 1481-8, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16781820

RESUMO

Arginine vasopressin and corticotropin-releasing factor are two neuroactive peptides that regulate hypothalamic-pituitary-axis and associated stress response. While the potential antidepressant and anxiolytic profiles of corticotropin-releasing factor 1 antagonists have been well studied, the concept of blockade of vasopressin system as another approach for the treatment of emotional processes has only been made available recently by the synthesis of the first non-peptide antagonist at the V1b receptor, SSR149415. In the present study SSR149415 has been compared with the corticotropin-releasing factor 1 antagonist SSR125543 and with anxiolytic and antidepressant drugs on the response of hippocampal cholinergic and cortical noradrenergic systems to the anxiogenic benzodiazepine receptor inverse agonist FG 7142. Acute (0.3-10 mg/kg, i.p.) and long-term administration (10 mg/kg, i.p., 21 days) of SSR149415 and SSR125543 reduced the FG 7142-induced increase in extracellular concentrations of acetylcholine in the hippocampus of anesthetized rats measured by microdialysis. By contrast acute and long-term administration of SSR149415 failed to reduce the FG 7142-induced increase in the release of norepinephrine in the cortex of freely moving rats. The present results demonstrate that the two compounds have similar profiles in a model of activation by an anxiogenic drug of the hippocampal cholinergic system and they suggest that SSR149415 and SSR125543 may have anti-stress anxiolytic and antidepressant effects via a mechanism of action different from classical benzodiazepine ligands and noradrenergic antidepressants.


Assuntos
Acetilcolina/metabolismo , Química Encefálica/efeitos dos fármacos , Carbolinas/farmacologia , Antagonistas GABAérgicos/farmacologia , Hidrocarbonetos Halogenados/farmacologia , Indóis/farmacologia , Norepinefrina/metabolismo , Pirrolidinas/farmacologia , Tiazinas/farmacologia , Análise de Variância , Animais , Antagonistas dos Receptores de Hormônios Antidiuréticos , Córtex Cerebral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Interações Medicamentosas , Hipocampo/efeitos dos fármacos , Masculino , Microdiálise/métodos , Ratos , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Fatores de Tempo
12.
Diagn Interv Imaging ; 97(5): 513-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26969120

RESUMO

The different factors involved in the choice of the best cardiovascular imaging examination for pediatric patients are justification, radiation protection, sedation, resolutions (spatial and contrast), morphology or function, intervention and contrast enhancement. Computed tomography is preferable for all coronary artery conditions, any arterial or venous abnormalities in newborns and infants and in the preoperative assessment for tetralogy of Fallot. Magnetic resonance imaging is used for any tumoral or functional assessment, cardiomyopathy or arrhythmia or if the child's participation and/or size of the structures being examined allows using this technique.


Assuntos
Anormalidades Cardiovasculares/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Anestesia , Criança , Cardiopatias Congênitas/cirurgia , Cardiopatias/cirurgia , Humanos , Aumento da Imagem , Lactente , Recém-Nascido , Imagem por Ressonância Magnética Intervencionista , Proteção Radiológica , Sensibilidade e Especificidade
13.
Neuropharmacology ; 43(5): 825-35, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12384168

RESUMO

In vivo microdialysis was used to investigate the interactions between dopamine (DA), glutamate (Glu) and aspartate (Asp) in anaesthetised-rat striatum. The combination of brain microdialysis and capillary electrophoresis with laser-induced fluorescence detection (CE-LIFD) allows the simultaneous monitoring of the efflux of these neurotransmitters up to every 10 s. DA and Glu reuptake inhibitors, nomifensine and L-trans-pyrrolidine-2,4-dicarboxylic acid (PDC) and, dopaminergic and glutamatergic receptor agonists, apomorphine and NMDA respectively, were administered by reverse dialysis. Reverse dialysis of 20 micro M nomifensine induced a rapid and marked increase (+3200% at 5 min) in extracellular DA, while a decrease in Glu and Asp (-11 and -25%, respectively) was observed simultaneously. Reverse dialysis of 10 micro M apomorphine led to progressive changes: -63% decrease in DA and +25% Glu increase at 36 min. Reverse dialysis of 1 mM NMDA induced a simultaneous increase in DA, Glu and Asp which peaked at +2 min (+840%, +40% and +150%, respectively). Surprisingly, a second increase in Glu was observed 5 min after the end of NMDA perfusion. Reverse dialysis of PDC (1 mM and 10 mM) induced a rapid increase in Glu and Asp levels, while DA increased with a 26-s delay. These findings indicate that, in the striatum, endogenous DA and Glu may act in opposition to regulate each other's efflux. These results have been obtained due to unique features offered by microdialysis coupled with CE-LIFD.


Assuntos
Apomorfina/farmacologia , Ácido Aspártico/metabolismo , Ácidos Dicarboxílicos/farmacologia , Agonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Dopamina/metabolismo , Agonistas de Aminoácidos Excitatórios/farmacologia , Ácido Glutâmico/metabolismo , N-Metilaspartato/farmacologia , Neostriado/metabolismo , Inibidores da Captação de Neurotransmissores/farmacologia , Nomifensina/farmacologia , Pirrolidinas/farmacologia , Animais , Eletrodos Implantados , Eletroforese Capilar , Masculino , Microdiálise , Neostriado/efeitos dos fármacos , Sistemas On-Line , Ratos , Ratos Sprague-Dawley
14.
Neuroreport ; 8(6): 1321-5, 1997 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-9172128

RESUMO

A porphyrinic microsensor combined with in vivo voltammetry was used to monitor extracellular nitric oxide (NO) in the locus coeruleus (LC) of anaesthetized rats. Administration of N omega-nitro-L-arginine p-nitro-anilide (100 mg/kg, i.p) or 7-nitro indazole (30 mg/kg, i.p.), which both inhibit preferentially neuronal NO synthase (NOS), induced a marked decrease in the NO oxidation peak height. On the other hand, N omega-nitro-L-arginine methyl ester (L-NAME) (200 mg/kg, i.p.), a less selective NOS inhibitor, failed to decrease the NO signal. Moreover, intra LC administration of NMDA, known to activate LC noradrenergic neurones, increased the NO signal. This study demonstrates the usefulness of in vivo voltammetry to monitor basal levels of NO and their changes in the LC. Differential effects of NOS inhibitors show that their central activity need to be assessed through in situ measurement of NO before using these inhibitors as neuropharmacological tools.


Assuntos
Inibidores Enzimáticos/farmacologia , Locus Cerúleo/efeitos dos fármacos , Monitorização Fisiológica/métodos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico/análise , Anilidas/farmacologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Eletroquímica , Indazóis/farmacologia , Locus Cerúleo/metabolismo , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Ratos , Ratos Sprague-Dawley
15.
Neuropeptides ; 37(2): 89-97, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12747940

RESUMO

In vivo microdialysis was employed to explore the effects of different selective non-peptides NK(1),NK(2) and NK(3) receptor antagonists on the corticotropin releasing factor (CRF)-induced release of acetylcholine (ACh) in the hippocampus of rats and guinea-pigs. In both species, the intracerebroventricular (i.c.v.) administration of CRF produced a time- and dose-dependent increase in hippocampal ACh release that was totally suppressed by an intraperitoneally (i.p.) pretreatment with the selective non-peptide CRF(1) receptor antagonist antalarmin (30 mg/kg). Pretreatment with the selective NK(2) receptor antagonist SR48968 (1mg/kg, i.p.) significantly reduced the increase of ACh induced by CRF. In contrast, its low-affinity enantiomer SR48965 (1mg/kg, i.p.) or the NK(1) receptor antagonist, GR205171 (1mg/kg, i.p.) did not exert any antagonist effect. Moreover, administration of the selective NK(3) receptor antagonist SR142801 (1mg/kg, i.p.) did not significantly reduce the CRF-induced hippocampal ACh release in guinea-pigs (the only species studied). The selective activity of SR48968 versus GR205171 or SR142801 indicates that NK(2) receptors play a major role in the control of CRF-induced hippocampal ACh release. Moreover, in freely moving rats, two sessions of stroking of the neck and back of the rat for 30 min, at 90 min intervals, known to be a stressful stimulus, produced a marked and reproducible increase in hippocampal ACh release. This effect was prevented by the administration of the two selective non-peptide CRF1 and NK(2) receptor antagonists antalarmin (30 mg/kg, i.p.) and SR48968 (1mg/kg, i.p.), respectively. This suggests that stress-induced activation of the hippocampal ACh system may be under the control of both endogenously released CRF and NKA, and opens the possibility of the existence of a functional interplay between the pathways containing these peptides as we observed in our experiments on anaesthetized animals.


Assuntos
Acetilcolina/metabolismo , Hipocampo/metabolismo , Receptores de Hormônio Liberador da Corticotropina/fisiologia , Receptores da Neurocinina-2/fisiologia , Animais , Benzamidas/farmacologia , Relação Dose-Resposta a Droga , Cobaias , Injeções Intraventriculares , Masculino , Microdiálise , Antagonistas dos Receptores de Neurocinina-1 , Estimulação Física , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Receptores da Neurocinina-2/antagonistas & inibidores , Especificidade da Espécie , Estereoisomerismo , Tetrazóis/farmacologia
16.
Neurosci Lett ; 261(3): 175-8, 1999 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-10081977

RESUMO

The present study investigated in vivo the kinetics of the changes in rat striatal extracellular concentrations of dopamine (DA), and its monoamine oxidase (MAO)-derived metabolite 3,4-dihydroxyphenylacetic acid (DOPAC), following administration either of nitric oxide (NO) synthase inhibitors 7-nitroindazole (7-NI) and N(omega)-nitro-L-arginine methyl ester (L-NAME) or of the widely used MAO inhibitor pargyline. DA and DOPAC concentrations were determined every 4 min by microdialysis combined with capillary zone electrophoresis coupled with laser-induced fluorescence detection (CZE-LIFD) and by differential normal pulse voltammetry (DNPV), respectively. Administration of 7-NI, both systemic (30 mg/kg, i.p.) or intrastriatal (1 mM through the microdialysis probe), as well as administration of pargyline (75 mg/kg, i.p.), induced simultaneously in the striatum a significant increase in extracellular DA and a significant decrease in extracellular DOPAC. On the other hand, administration of L-NAME (200 mg/kg, i.p.) produced a significant increase in striatal extracellular DA without changes in extracellular DOPAC. These data suggest a possible MAO inhibitory effect of 7-NI which seems to be restricted to this NOS inhibitor. These results may be of special interest for the studies on the functional role of NO in the brain, particularly in dopaminergic transmission.


Assuntos
Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Dopamina/metabolismo , Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Neostriado/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Cromatografia Capilar Eletrocinética Micelar , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Masculino , Microdiálise , NG-Nitroarginina Metil Éster/farmacologia , Neostriado/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III , Pargilina/farmacologia , Ratos , Ratos Sprague-Dawley
17.
Neurosci Lett ; 264(1-3): 5-8, 1999 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-10320000

RESUMO

The present study investigated in vivo the kinetic of the changes in rat striatal extracellular concentrations of dopamine (DA), and its monoamine oxidase (MAO)-derived metabolite 3,4-dihydroxyphenylacetic acid (DOPAC), following administration either of nitric oxide (NO) synthase (NOS) inhibitors 7-nitroindazole (7-NI) and Nomega-nitro-l-arginine methyl ester (L-NAME) or of the widely used MAO inhibitor pargyline. DA and DOPAC concentrations were determined every 4 min by microdialysis combined with capillary zone electrophoresis coupled with laser-induced fluorescence detection (CZE-LIFD) and by differential normal pulse voltammetry (DNPV), respectively. Administration of 7-NI, both systemic (30 mg/kg, intraperitoneally, i.p.) or intrastriatal (1 mM through the microdialysis probe), as well as administration of pargyline (75 mg/kg, i.p.), induced simultaneously in the striatum a significant increase in extracellular DA and a significant decrease in extracellular DOPAC. However, administration of L-NAME (200 mg/kg, i.p.) produced a significant increase in striatal extracellular DA without changes in extracellular DOPAC. These data suggest a possible MAO inhibitory effect of 7-NI which seems to be restricted to this NOS inhibitor. These results may be of special interest for the studies on functional role of NO in the brain, particularly in dopaminergic transmission.


Assuntos
Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Dopamina/metabolismo , Inibidores Enzimáticos/farmacologia , Espaço Extracelular/metabolismo , Indazóis/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Eletrofisiologia/métodos , Masculino , Microdiálise , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo I , Pargilina/farmacologia , Ratos , Ratos Sprague-Dawley
18.
Ann Med Psychol (Paris) ; 150(2-3): 240-4: discussion 245, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1343526

RESUMO

A 24 hour ambulatory EEG study performed in a population of 300 non epileptic outpatients with an anxious and depressive pathology revealed a high prevalence of abnormalities in subjects referred with panic disorder. Two groups of 150 medication-free patients each have been selected on the base of DSM-III-R = one with panic attacks (PA), the other with depressive patients without paroxystic anxiety (DS). The results showed respectively = in the PA group 63.2% abnormal, 19.7% normal and 17.1% dubious records. In the DS group = 74.5% normal, 18.3% abnormal and 7.2% dubious records. Epileptiform abnormalities were 4 times more frequent in the PA group (80%) than in the DS group (20%). Two nycthemeral peaks were found (5-8 pm and 3 hours after awakening). MRI has permitted the discovery of abnormal cerebral images in 3 patients of the PA group (cyst of the insula, temporal and parietal cryptic angiomas, sequelae of a parietal vasculo-cerebral stroke) frequency appearing to be clearly superior to the one resulting from recent epidemiologic data. The subclinical character of 2/3 of these abnormalities refers beyond epilepsy to their signification in the field of emotive and intellectual disturbances. The paradoxal efficiency of tricyclic drugs in panic disorder, sets the problem of their eventual antiepileptic action at low doses. If recent data on standard EEG in panic disorder is available, we did not find any similar study to ours in order to confront our results.


Assuntos
Nível de Alerta/fisiologia , Ritmo Circadiano/fisiologia , Eletroencefalografia , Monitorização Fisiológica , Transtorno de Pânico/fisiopatologia , Adulto , Assistência Ambulatorial , Córtex Cerebral/fisiopatologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Diagnóstico Diferencial , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno de Pânico/diagnóstico , Transtorno de Pânico/psicologia
19.
Cancer Chemother Pharmacol ; 73(6): 1303-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24705976

RESUMO

INTRODUCTION: In the literature, data on the effect of renal impairment on the pharmacokinetics of anticancer drugs are scarce. Here, we report a 68-year-old metastatic osteosarcoma patient with impaired renal function due to prior chemotherapy, who was treated on compassionate use basis with 400 mg/m(2) cetuximab. MATERIAL AND METHODS: Pharmacokinetic parameters after the first dose, including dose-normalised AUC from time zero to day 7, clearance, elimination half-life (t(1/2)), were estimated using trapezoidal non-compartmental methods and compared to pharmacokinetic data from a study population with normal kidney function. RESULTS: The results showed that the pharmacokinetics of cetuximab in this patient with renal failure was similar to that with adequate renal function. CONCLUSION: This study suggests that cetuximab can be safely used in cancer patients with renal impairment without dose adjustment.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Insuficiência Renal/metabolismo , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Cetuximab , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Diálise Renal , Insuficiência Renal/terapia
20.
Ann Chir Plast Esthet ; 51(4-5): 423-8, 2006.
Artigo em Francês | MEDLINE | ID: mdl-17014947

RESUMO

Management of cystic lymphangioma necessitate for optimal diagnosis and treatment the expertise of a trained multidisciplinary team including dermatologists, radiologists, plastic and vascular surgeons. An initial imaging work-up of these lesions by ultrasound Doppler examination and MR imaging are necessary before treatment planning. Depending of the size, the location, the risk for the adjacent organs, a therapeutic decision may be mandatory. Percutaneous sclerotherapy is a safe and efficient treatment. It is the treatment of choice that must be proposed in first intention.


Assuntos
Anormalidades Linfáticas/terapia , Fatores Etários , Humanos , Linfangioma Cístico/terapia , Anormalidades Linfáticas/diagnóstico , Imageamento por Ressonância Magnética , Planejamento de Assistência ao Paciente , Soluções Esclerosantes/administração & dosagem , Soluções Esclerosantes/uso terapêutico , Escleroterapia/métodos , Ultrassonografia Doppler
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA