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1.
Eur J Clin Pharmacol ; 70(2): 127-34, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24145817

RESUMO

PURPOSE: Most schizophrenic patients have mild to moderate cognitive impairment in the early stages of schizophrenia. The aim was to compare the long-term effects of various antipsychotic drugs on overall cognition and on specific cognitive domains in patients with schizophrenia or related disorders. METHODS: We searched MEDLINE and EMBASE for randomized controlled trials in which oral formulations of second-generation antipsychotic drugs were compared head-to-head or against placebo or against haloperidol. Trials had to be of at least 6 months duration to be included. We used a network meta-analysis to combine direct and indirect comparisons of the cognitive effects between antipsychotics. RESULTS: Nine studies were eligible. The median trial duration was 52 weeks. Quetiapine, olanzapine and risperidone had better effects on global cognitive score than amisulpride (p < 0.05) and haloperidol (p < 0.05). When memory tasks were considered, ziprasidone had better effect than amisulpride (0.28 [0.02-0.54]) and haloperidol (0.32 [0.09-0.55]). Quetiapine was better than other drugs (p < 0.001) on attention and processing speed tasks, followed by ziprasidone (p < 0.05) and olanzapine (p < 0.05). The effects of quetiapine, risperidone and olanzapine were better than those of amisulpride (p < 0.05) on executive functions. CONCLUSIONS: Our results suggest differences between antipsychotics in their effect on the overall cognitive score in schizophrenia. Quetiapine and olanzapine had the most positive effects, followed by risperidone, ziprasidone, amisulpride and haloperidol in that order. Significant differences were also observed according to specific cognitive tasks.


Assuntos
Antipsicóticos/efeitos adversos , Transtornos Cognitivos/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Cognição/efeitos dos fármacos , Humanos
2.
Clin Pharmacol Ther ; 83(2): 328-35, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17713475

RESUMO

The objective of the study was to evaluate the effect of mycophenolate mofetil (MMF) on the regulation of inosine monophosphate dehydrogenase (IMPDH) during the first 2 years after renal transplantation. Twelve patients were enrolled, and 10-h time-course evaluations of the effects of MMF were regularly performed during the study. IMPDH activity and gene expression were measured in whole blood and in mononuclear cells, respectively. Type I IMPDH (IMPDH-I) mRNA was increased during the first 3 months following transplantation and reached its maximal level during acute rejection episodes, whereas type II IMPDH mRNA was stable. Furthermore, although no alteration in the predose samples was observed, patients with prolonged MMF treatment exhibited an increase in the induction potency of both IMPDH activity and gene expression. In vitro experiments confirmed that IMPDH-I is inducible, but preferentially in monocytes than in lymphocytes. This finding suggests that the measurement of IMPDH mRNAs may provide reliable information to predict acute rejection.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Rejeição de Enxerto/prevenção & controle , IMP Desidrogenase/sangue , Imunossupressores/uso terapêutico , Transplante de Rim , Leucócitos Mononucleares/efeitos dos fármacos , Ácido Micofenólico/análogos & derivados , Adulto , Idoso , Biomarcadores/sangue , Células Cultivadas , Feminino , Seguimentos , Rejeição de Enxerto/enzimologia , Humanos , IMP Desidrogenase/genética , Imunossupressores/farmacocinética , Leucócitos Mononucleares/enzimologia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/farmacocinética , Ácido Micofenólico/uso terapêutico , Estudos Prospectivos , RNA Mensageiro/sangue , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
3.
Am J Med Genet B Neuropsychiatr Genet ; 147B(4): 491-4, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18085566

RESUMO

The identification of genetic factors underlying individual differences in antipsychotic drug response is of major interest. We investigated the involvement of two norepinephrine transporter gene polymorphisms in response to antipsychotics, comparing patients with strong and weak response to olanzapine and risperidone. We prospectively assessed short-term drug response in 75 Caucasian schizophrenic patients treated with these drugs, using the Positive and Negative Syndrome Scale. We then assessed the association between two SLC6A2 gene polymorphisms and drug response in this sample. No significant difference in genotype distribution was found between responders and non-responders, for the G1287A or T-182C polymorphism. The improvement in PANSS positive subscore was significantly greater in patients homozygous for the A1287 allele than in other patients, and significantly smaller in patients homozygous for the C-182 allele than in other patients. Our results suggest that these polymorphisms are specifically involved in the variation of positive symptoms in schizophrenic patients.


Assuntos
Antipsicóticos/farmacocinética , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Esquizofrenia/tratamento farmacológico , Adulto , Benzodiazepinas , Feminino , Genótipo , Humanos , Masculino , Olanzapina , Farmacogenética , Polimorfismo Genético , Escalas de Graduação Psiquiátrica , Risperidona
4.
Eur J Neurol ; 14(12): 1313-6, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17941858

RESUMO

Whether nicotine has therapeutic effects on Parkinson's disease (PD) symptoms is controversial, but high doses and chronic treatment have never been tested. We report the results of a pilot, open-label trial to assess the safety and possible efficacy of chronic high doses of nicotine. Six patients with advanced idiopathic PD received increasing daily doses of transdermal nicotine up to 105 mg/day over 17 weeks. All patients but one accepted the target dose. Nausea and vomiting were frequent but moderate, and occurred in most of the patients (four of six) who received over 90 mg/day and 14 weeks of nicotine treatment. During the plateau phase, patients improved their motor scores and dopaminergic treatment was reduced. These results confirm the feasibility of chronic high dose nicotinic treatment in PD but warrant validation of the beneficial effects by a randomized controlled trial.


Assuntos
Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Doença de Parkinson/tratamento farmacológico , Administração Cutânea , Agonistas de Dopamina/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Sinergismo Farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Nicotina/efeitos adversos , Agonistas Nicotínicos/efeitos adversos , Projetos Piloto , Resultado do Tratamento
5.
Diabet Med ; 24(9): 1012-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17535291

RESUMO

AIMS: The metabolic syndrome is a cluster of cardiovascular risk factors which include central obesity, dyslipidaemia, glucose intolerance and hypertension. These risk factors are common in patients with growth hormone (GH) deficiency, suggesting a role for the somatotropic axis in the development of metabolic syndrome. METHODS: We used factor analysis to investigate the relationships linking serum levels of GH and insulin-like growth factor I (IGF-I) to metabolic syndrome variables (high-density lipoprotein cholesterol, triglycerides, fasting glucose, blood pressure and waist circumference). We studied 359 men and 388 women from the Data from an Epidemiological Study on the Insulin Resistance syndrome (DESIR). Their age range was 30-64 years. RESULTS: Three independent latent factors explained 61% of the total variance in women and four factors explained 73% in men. In both men and women, IGF-I showed a strong positive correlation with the lipid factor and a negative correlation with the obesity/glucose factor. In women, GH showed a strong negative correlation with the obesity/glucose factor but not the lipid factor. In men, GH was unrelated to the lipid and obesity/glucose factors. The blood pressure factor was not related to GH or IGF-I. In contrast with IGF-I, GH was significantly lower in women with metabolic syndrome (1575 +/- 449 pg/ml) than in the other women (2121 +/- 520 pg/ml, P = 0.002). No significant difference was observed in men for GH or IGF-I. CONCLUSION: Our results support a link between the somatotropic axis and several features of the metabolic syndrome, and suggest distinct effects of GH and IGF-I on these parameters.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/complicações , Hormônio Liberador de Hormônio do Crescimento , Hormônio do Crescimento Humano/deficiência , Fator de Crescimento Insulin-Like I , Síndrome Metabólica/complicações , Adulto , Composição Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Masculino , Síndrome Metabólica/tratamento farmacológico , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Inquéritos e Questionários
6.
J Cardiovasc Electrophysiol ; 12(6): 639-44, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11405396

RESUMO

INTRODUCTION: The aim of this study was to evaluate simultaneously cardiac autonomic activity, through heart rate variability (HRV) analysis, and cardiac inotropic changes during head-up tilt (HUT) in patients with recurrent vasovagal syncope. METHODS AND RESULTS: Twelve subjects implanted with a permanent dual-chamber pacemaker for recurrent vasovagal syncope characterized by marked bradycardia were studied. The tip of the right ventricular electrode was equipped with a sensor that measured peak endocardial acceleration (PEA) as an index of myocardial contractility. RR interval and PEA signals were acquired simultaneously and processed in the time and frequency (low frequencies [LF] and high frequencies [HF] of RR signal) domain during early HUT (T1), late HUT, or before syncope (T2). In the six subjects with positive HUT: (1) Abnormal heart rate oscillations were evidenced at T1 and discriminated this group from the negative group (LF/HF decreased by 46% from supine to T1, but increased by 55% in the negative group; P < 0.01 positive vs negative HUT). (2) Gradual diminution of the HF component was associated with an increase in PEA index during HUT with a correlation between PEA/RR interval (R = -0.8, P < 0.001), PEA/HF components (R = -0.6, P < 0.05). (3) Sympathetic stimulation responsible for changes in both HRV and PEA parameters occurred immediately before the faint (LF/LF+HF: 0.6 +/- 0.2 to 0.8 +/- 0.09; P < 0.05 T2 vs T1; PEA: 0.62 +/- 0.10G to 0.83 +/- 0.22G; P < 0.01 T2 vs T1). CONCLUSION: Our findings showed that a homogeneous subgroup of patients with recurrent vasovagal syncope and positive HUT exhibited abnormal cardiac autonomic and inotropic responses to an orthostatic stimulus. Continuous changes over time of HRV and PEA parameters highlight the dynamic behavior of the mechanisms leading to syncope.


Assuntos
Frequência Cardíaca/fisiologia , Contração Miocárdica/fisiologia , Síncope Vasovagal/fisiopatologia , Adulto , Eletrocardiografia , Feminino , Humanos , Masculino , Postura/fisiologia , Processamento de Sinais Assistido por Computador , Síncope/fisiopatologia
7.
Eur J Heart Fail ; 3(2): 189-95, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11246056

RESUMO

BACKGROUND: We assessed the behavior of the baroreflex (BR) gain in chronic heart failure (CHF) patients using the spectral analysis method during application of a forcing stimulus, i.e. respiration. METHODS: Simultaneous RR interval and arterial pressure fluctuation recordings were obtained during two random-order periods of voluntary paced-breathing (0.15 Hz and 0.25 Hz) in seven patients with moderate CHF (NYHA class II/III; EF, 30+/-9%; peak VO(2), 18+/-5 ml kg(-1) min(-1)) and six age-matched controls. BR gain was assessed in the time (sequential method) and frequency (cross-spectral gain in the low and high frequency) domains. RESULTS: Slower breathing was associated with a BR gain decrease in CHF patients whereas a BR gain increase was evidenced in controls (BR gain: 6+/-5 ms mmHg(-1) at 0.25 Hz vs. 4+/-3 ms mmHg(-1) at 0.15 Hz, P<0.05 in CHF; BR gain: 12+/-7 ms mmHg(-1) at 0.25 Hz vs. 15+/-7 ms mmHg(-1) at 0.15 Hz, P<0.05 in controls). CONCLUSIONS: Voluntary breathing, which involves cortical centers in the brain, had major effects on cardiovascular system controller gain in CHF patients, indicating an impairment of the central neural regulation of the autonomic outflow.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Pressorreceptores/fisiopatologia , Ventilação Pulmonar/fisiologia , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Biorretroalimentação Psicológica/fisiologia , Pressão Sanguínea/fisiologia , Doença Crônica , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
9.
Therapie ; 54(3): 353-5, 1999.
Artigo em Francês | MEDLINE | ID: mdl-10500450

RESUMO

Women appear to be protected, until the menopause, from the development of coronary artery syndromes. This protective effect seems to be due to the beneficial effect of ovarian hormones, in particular oestrogens. A number of potential mechanisms for the protective effect of oestrogens have been proposed. An important postulated mechanism could be by improving the function of vascular endothelium. In this review, we present the currently published studies that have evaluated the effects of 17 beta-estradiol, the only oestrogen used in France for hormone replacement therapy, on peripheral and coronary vasomotor function in postmenopausal women.


Assuntos
Vasos Sanguíneos/fisiologia , Circulação Coronária/fisiologia , Endotélio Vascular/fisiologia , Estradiol/farmacologia , Estradiol/fisiologia , Terapia de Reposição de Estrogênios , Pós-Menopausa , Circulação Sanguínea/efeitos dos fármacos , Circulação Sanguínea/fisiologia , Vasos Sanguíneos/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos
10.
Biol Psychiatry ; 45(8): 1066-9, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10386194

RESUMO

AIM OF THE STUDY: This study investigated the possible connection between serum cholesterol levels and platelet serotonin (5-HT) content in violent suicide attempters and matched controls. METHODS: Blood samples for cholesterol and platelet 5-HT levels were obtained from 17 drug-free patients within 3 days after the suicide attempt. RESULTS: Serum cholesterol and platelet 5-HT levels in the suicide attempters were significantly lower than in the controls; however, we did not find any significant correlation between these two variables. Indeed, three clinical dimensions are present in this patient group: suicidality, violence, and impulsiveness. Because we did not find a difference in cholesterol and platelet 5-HT levels between impulsive and nonimpulsive patients, these two indexes may more reflect the dimension of suicidality and/or violence. CONCLUSIONS: Further investigation is necessary to study the dependence of these two peripheral abnormalities within the context of violent suicidal behavior.


Assuntos
Plaquetas/química , Colesterol/sangue , Serotonina/análise , Tentativa de Suicídio , Violência , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Clin Sci (Lond) ; 93(1): 21-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9279199

RESUMO

1. Changes in the low-frequency (LF) components of blood pressure and heart rate variability and in the ratio of LF to high-frequency (HF) components of heart rate variability (LF/HF ratio) are used to assess acute changes in sympathetic control of blood pressure or heart rate and in sympathovagal balance that occur in response to physiological or pharmacological stimuli. Before these spectral indexes can be used to assess the effects of drug therapy or other clinical interventions on reflex sympathetic activity, their repeatability must be evaluated. 2. Intra-observer repeatability was studied by analysing changes in the LF components (expressed as absolute or normalized units) of cardiovascular variability and in the LF/HF ratio during sympathetic activation induced by nitroglycerin infusion (n = 10 subjects) or 60 degrees head-up tilt (n = 13 subjects) repeated on two occasions, 2 days and 1 week apart respectively, in healthy young male volunteers. Repeatability was estimated as recommended by Bland and Altman. 3. Bland and Altman's plots of the repeatability of changes in the LF components and LF/HF ratio showed that measurements were sufficiently repeatable to be used over periods of time of up to 1 week in clinical studies. 4. The sample-size tables derived from our results show that expression of spectral components as normalized units, and use of a cross-over design, minimize the number of subjects to be included in clinical studies conducted using similar designs and LF component changes as endpoints.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Nitroglicerina , Processamento de Sinais Assistido por Computador , Sistema Nervoso Simpático/efeitos dos fármacos , Vasodilatadores , Adulto , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estimulação Química
13.
Eur Respir J ; 9(12): 2517-24, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8980963

RESUMO

An oxidant-antioxidant imbalance in neonatal alveolar macrophages (AMs) may contribute to the increased susceptibility to lung injury described in the neonatal period. We therefore evaluated oxygen radical production by rat AMs at various postnatal ages, and measured in parallel cellular antioxidant enzyme activities. AMs were obtained by bronchoalveolar lavage from rats aged < 24 h, 21 days and 5 weeks, and results were compared to those obtained with adult rat AMs. Intracellular production of oxygen radical species, estimated fluorometrically using 2',5'-dichlorofluorescein diacetate as the substrate, was significantly reduced in neonates as compared with adults, both in the presence and in the absence of cell stimulation with phorbol myristate acetate (PMA) or opsonized zymosan. A similar pattern was observed for the extracellular release of oxygen radical species, evaluated by lucigenin-enhanced chemiluminescence (CL) or peroxidase-catalysed CL oxidation of luminol: peak CL values measured after cell stimulation with PMA or opsonized zymosan remained significantly lower for AMs from newborn rats than for AMs from adults. By contrast, high values for antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase) in AMs were demonstrated in newborns as compared to adults. We conclude that high antioxidant activity in rat AMs after birth may be at least partly responsible for the low production of oxygen metabolites observed during the same period.


Assuntos
Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Macrófagos Alveolares/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Líquido da Lavagem Broncoalveolar , Feminino , Medições Luminescentes , Masculino , Ratos , Ratos Sprague-Dawley
14.
Hum Exp Toxicol ; 15(12): 964-71, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8981100

RESUMO

Sulfur mustard (SM) represents a potential chemical warfare agent. In order to characterize SM-induced airway epithelial damage, we studied the effects of an intratracheal injection of 0.3 mg/kg of SM in guinea pigs, 5 h, 24 h, 14 days and 35 days after exposure. During the acute period, lesions prevailed in tracheal epithelium exhibiting intra-epithelial blisters, inflammatory cell infiltration and columnar cell shedding with exposure of basal cells. Fourteen days after intoxication, tracheal epithelium appeared disorganized and showed a significant decrease in height and cell density. Tracheal epithelium recovery was still not complete even 35 days after SM-intoxication. At day 14, in SM-intoxicated guinea pigs treated with betamethasone from day 7 to day 14, epithelium height, cell density and cell proliferation (evaluated by immunohistochemistry) were significantly increased compared to untreated guinea pigs. In conclusion, the lesions observed in SM-intoxicated guinea pigs seem to be in accordance with clinical human observations and are relevant to the study of airway epithelial damage induced by SM. This animal model could be used to illustrate tracheal epithelium regeneration mainly derived from basal cells and to show glucocorticoid effects on airway epithelial recovery after chemical aggression.


Assuntos
Betametasona/uso terapêutico , Gás de Mostarda/toxicidade , Traqueia/efeitos dos fármacos , Traqueia/patologia , Animais , Vias de Administração de Medicamentos , Epitélio/efeitos dos fármacos , Epitélio/patologia , Epitélio/ultraestrutura , Cobaias , Intubação Intratraqueal , Masculino , Gás de Mostarda/administração & dosagem , Traqueia/ultraestrutura
15.
Fundam Clin Pharmacol ; 10(6): 518-23, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8985721

RESUMO

To investigate the role of tachykinins in pentamidine-induced bronchoconstriction and airway microvascular leakage in the guinea pig, we examined the effects on bronchoconstriction and microvascular leakage of the nonpeptide antagonists of NK1 and NK2 tachykinin-receptors, respectively, CP-96,345 and SR 48968. Respiratory system resistance was measured by the occlusion method in anaesthetized, tracheotomized and mechanically ventilated guinea pigs. Airway microvascular permeability was evaluated by measuring the quantity of Evans blue dye in the trachea and main bronchi. Aerosolized CP-96,345 or SR 48968 partially abolished pentamidine-induced bronchoconstriction (at 5 to 30 mg/mL pentamidine; 60 breaths) whereas the combination of the two prevented it. In contrast, CP-96,345 and SR 48968 did not prevent the increase in airway microvascular permeability induced by pentamidine (50 mg/mL; 90 breaths) whether they were administered separately or together, by aerosol or intravenously. These results demonstrate that in the guinea pig, pentamidine-induced bronchoconstriction is mediated through both NK1 and NK2 tachykinin-receptor activation and that when directly administered into the airways, tachykinin antagonists effectively prevent pentamidine-induced bronchoconstriction.


Assuntos
Benzamidas/farmacologia , Compostos de Bifenilo/farmacologia , Broncoconstrição/efeitos dos fármacos , Piperidinas/farmacologia , Receptores da Neurocinina-2/antagonistas & inibidores , Substância P/antagonistas & inibidores , Aerossóis , Animais , Benzamidas/administração & dosagem , Compostos de Bifenilo/administração & dosagem , Brônquios/irrigação sanguínea , Permeabilidade Capilar/efeitos dos fármacos , Relação Dose-Resposta a Droga , Cobaias , Masculino , Pentamidina , Piperidinas/administração & dosagem
16.
Am J Respir Crit Care Med ; 152(5 Pt 1): 1611-5, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7582303

RESUMO

The feasibility of spirometry or respiratory impedance measurements for assessing lung function in the elderly was compared in 208 institutionalized patients with various degrees of cognitive function impairment. Respiratory impedance was determined by the forced oscillation technique. Cognitive function was assessed by the score for the mini-mental state (MMS) examination. Of the 208 patients, 126 had severe cognitive impairment (MMS < or = 17), 36 had mild impairment (18 < or = MMS < or = 23), and 46 had no impairment (MMS > or = 24). Of the 208 patients, respiratory impedance measurements were possible in 159, whereas in only 85 was spirometry possible. The overall difference between the feasibility rates for the spirometric and respiratory impedance measurements was highly significant (chi 2 = 71.4; p < 10(-6)). The difference between the feasibility rates for the two techniques was higher in the group of subjects with severe cognitive impairment than in the groups with mild impairment and no impairment, respectively. Among the 84 patients able to complete both tests, significant correlations were found between the spirometric and respiratory impedance measurements. These results indicate that respiratory impedance measurement seems a more useful tool than spirometry for assessing lung function in elderly patients whenever cognitive function is impaired.


Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Pulmão/fisiologia , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/fisiopatologia , Intervalos de Confiança , Estudos de Viabilidade , Feminino , Humanos , Funções Verossimilhança , Modelos Logísticos , Masculino , Testes Psicológicos/estatística & dados numéricos , Testes de Função Respiratória/métodos , Testes de Função Respiratória/estatística & dados numéricos
17.
Am J Physiol ; 269(5 Pt 1): L631-6, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7491982

RESUMO

To determine whether tachykinins induce gelatinase production by guinea pig alveolar macrophages (AM), and to characterize the mechanism involved, we incubated AM with substance P (SP), neurokinin A (NKA), or the NH2-terminal fragment of SP, SP(1-7). The effects of increasing concentrations of selective NK1 and NK2 agonists on tachykinin-induced gelatinase production were also evaluated, as were the effects of a selective NK2 antagonist. Gelatinase activity in conditioned culture media (CCM) was assessed by zymography and quantified by image analysis. SP increased 92-kDa gelatinase activity in CCM of AM in a concentration-dependent manner, with a maximum increase at 10(-4) M. NKA, the NH2-terminal fragment of SP, and an NK1-selective agonist had no effect. In contrast, a selective NK2 agonist induced a concentration-dependent increase in gelatinase activity. The increase in this activity induced by SP and the selective NK2 agonist was inhibited by a selective NK2 antagonist. We conclude that SP induces gelatinase production by AM through NK2 receptor activation. The release of gelatinase may constitute one mechanism through which SP contributes to the epithelial lesions observed in bronchial hyperreactivity and asthma.


Assuntos
Gelatinases/biossíntese , Macrófagos Alveolares/enzimologia , Receptores da Neurocinina-2/fisiologia , Taquicininas/farmacologia , Animais , Células Cultivadas , Meios de Cultura , Cobaias , Masculino , Receptores da Neurocinina-2/agonistas , Receptores da Neurocinina-2/antagonistas & inibidores , Substância P/farmacologia
18.
Chest ; 108(1): 41-7, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7606989

RESUMO

The forced oscillation technique (FOT) is a noninvasive test used to characterize the mechanical impedance of the respiratory system. The aim of the study was to compare the changes in respiratory conductance (Grs) measured with FOT to those in FEV1 in 22 patients with asthma and 20 patients with chronic obstructive pulmonary diseases (COPD) after salbutamol inhalation. FEV1 and Grs indexes, computed as the ratio of the difference between postbronchodilator and prebronchodilator values over the predicted value, were used to express reversibility of airway obstruction. After inhalation of salbutamol in cumulative doses up to 1,200 micrograms in ten patients of each group, FEV1 and Grs indexes showed parallel changes, and most of the increase was observed after the first dose of 200 micrograms of salbutamol for the two indexes. In all the 42 patients, we found a linear relationship between the two indexes after inhalation of 200 micrograms of salbutamol (r = 0.7, p < 0.0001). We evaluated FEV1 and Grs indexes in terms of sensitivity and specificity for identifying asthmatics among patients with COPD: using a 10% change as the cut-off value, these indexes proved of similar value (sensitivity, 0.91 and 0.95; specificity, 0.95 and 0.85, respectively). We conclude that the use of FOT can be considered as an alternative to forced expiration for detecting bronchodilatation in asthmatics and patients with COPD.


Assuntos
Resistência das Vias Respiratórias , Albuterol/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Pneumopatias Obstrutivas/tratamento farmacológico , Testes de Função Respiratória , Espirometria , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Resultado do Tratamento
19.
Am J Respir Crit Care Med ; 151(6): 1939-45, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7767543

RESUMO

The functional immaturity of neonatal alveolar macrophages (AM) may contribute to the increased susceptibility of neonates to lung injury. Because the secretion of proteinases by neonatal AMs may be involved in normal postnatal lung development and in repair after lung injury, we evaluated the capacity of neonatal AMs to secrete 92 kD Type IV collagenase. AMs were obtained by bronchoalveolar lavage from newborn rats at different postnatal ages. Total gelatinase activity was measured by zymography in AM-conditioned media. Spontaneous secretion of gelatinase from AMs varied significantly with age, the highest levels being found immediately after birth. Stimulation of AMs by PMA induced a four- to fivefold greater increase in total gelatinase activity during the first 10 d of postnatal life compared with adulthood. Using [3H]gelatin as the substrate, we found high free gelatinase activity only within 24 h after birth; data obtained after exposing cells to natural surfactant suggested that surfactant may account in part for this increase in free gelatinase activity. No secretion of tissue inhibitor of metalloproteinases (TIMP) by AMs was detectable in newborns within 24 h after birth. We conclude that AMs from newborn rats are able to secrete more gelatinase than AMs from adults, and this enzyme production profile during the neonatal period may contribute to the fact that newborns with lung injury are at high risk for extracellular matrix degradation.


Assuntos
Gelatinases/metabolismo , Macrófagos Alveolares/enzimologia , Animais , Animais Recém-Nascidos , Líquido da Lavagem Broncoalveolar/citologia , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Feminino , Glicoproteínas/metabolismo , Immunoblotting , Macrófagos Alveolares/efeitos dos fármacos , Masculino , Inibidores de Metaloproteinases de Matriz , Metaloendopeptidases/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Estimulação Química , Acetato de Tetradecanoilforbol/farmacologia , Inibidores Teciduais de Metaloproteinases
20.
J Appl Physiol (1985) ; 77(5): 2325-32, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7532648

RESUMO

To explore the mechanisms of airway hyperreactivity to aerosolized substance P observed in guinea pigs 14 days after intratracheal injection of sulfur mustard (SM), we studied the effects of epithelium removal and inhibition of neutral endopeptidase (NEP) activity on airway muscle responsiveness. Tracheal rings from SM-intoxicated guinea pigs expressed a greater contractile response to substance P than rings from nonintoxicated guinea pigs. After epithelium removal or incubation with the NEP inhibitor phosphoramidon, the contractile responses of tracheal rings to substance P did not differ in guinea pigs injected with SM or ethanol (SM solvent). Treatment of the guinea pigs with betamethasone for 7 days before measurement abolished the airway muscle hyperresponsiveness observed in untreated SM-intoxicated guinea pigs and partially restored tracheal epithelium NEP activity. In addition, the tracheal epithelium height and cell density of SM-intoxicated guinea pigs treated with betamethasone were significantly greater than in those without betamethasone. These results demonstrate that SM intoxication induces airway muscle hyperresponsiveness to substance P by reducing tracheal epithelial NEP activity and that glucocorticoids might inhibit this hyperresponsiveness by increasing this activity.


Assuntos
Betametasona/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Gás de Mostarda/toxicidade , Substância P/antagonistas & inibidores , Traqueia/efeitos dos fármacos , Administração por Inalação , Aerossóis , Animais , Células Epiteliais , Epitélio/efeitos dos fármacos , Epitélio/enzimologia , Etanol/toxicidade , Glicopeptídeos/farmacologia , Cobaias , Masculino , Músculo Liso/citologia , Músculo Liso/enzimologia , Músculo Liso/fisiologia , Neprilisina/antagonistas & inibidores , Neprilisina/metabolismo , Traqueia/citologia , Traqueia/enzimologia , Traqueia/fisiologia
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