Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros












Intervalo de ano de publicação
1.
Appl Spectrosc ; 73(10): 1208-1217, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31219322

RESUMO

Brain ischemia represents a leading cause of death and disability in industrialized countries. To date, therapeutic intervention is largely unsatisfactory and novel strategies are required for getting better protection of neurons injured by cerebral blood flow restriction. Recent evidence suggests that brain insulin leads to protection of neuronal population undergoing apoptotic cell death via modulation of oxidative stress and mitochondrial cytochrome c (CytC), an effect to be better clarified. In this work, we investigate on the effect of insulin given intracerebroventricular (ICV) before inducing a transient global ischemia by bilateral occlusion of the common carotid arteries (BCCO) in Mongolian gerbils (MG). The transient (3 min) global ischemia in MG is observed to produce neurodegenerative effect mainly into CA3 hippocampal region, 72 h after cerebral blood restriction. Intracerebroventricular microinfusion of insulin significantly prevents the apoptosis of CA3 hippocampal neurons. Histological observation, after hematoxylin and eosin staining, puts in evidence the neuroprotective role of insulin, but Raman microimaging provides a clearer insight in the CytC mechanism underlying the apoptotic process. Above all, CytC has been revealed to be an outstanding, innate Raman marker for monitoring the cells status, thanks to its resonant scattering at 530 nm of incident wavelength and to its crucial role in the early stages of cells apoptosis. These data support the hypothesis of an insulin-dependent neuroprotection and antiapoptotic mechanism occurring in the brain of MG undergoing transient brain ischemia. The observed effects occurred without any peripheral change on serum glucose levels, suggesting an alternative mechanism of insulin-induced neuroprotection.


Assuntos
Apoptose , Isquemia Encefálica/tratamento farmacológico , Região CA3 Hipocampal/efeitos dos fármacos , Citocromos c/fisiologia , Insulina/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Gerbillinae , Infusões Intraventriculares , Insulina/administração & dosagem , Masculino , Mitocôndrias/efeitos dos fármacos , Neuroproteção , Fármacos Neuroprotetores/administração & dosagem , Análise Espectral Raman/métodos
2.
Psicol. reflex. crit ; 28(3): 454-462, Jul-Sep/2015. tab, graf
Artigo em Inglês | LILACS, INDEXPSI | ID: lil-752002

RESUMO

Anxiety disorders are highly prevalent among school-aged children. These disorders become chronic in a substantial proportion of youths and cause significant interference with daily functioning. The purpose of the current investigation was to examine the psychometric properties of the Portuguese version of the Child Anxiety Life Interference Scale - Parent and Child versions (CALIS-P and CALIS-C). The sample consisted of 132 children between the ages of 7 and 12 with a main diagnosis of anxiety disorder and their parents. A factor analysis of the CALIS-P yielded three factors that agreed with the hypothesised subscales of At Home, Outside Home and Parent Life interference. For the CALIS-C, a factor analysis yielded two factors corresponding to Close Relationships and Performance interference that did not match the subscales of the original version. The internal consistency of the various CALIS subscales was good. Finally, evidence was found for both convergent and divergent validity. The CALIS scores were also significantly correlated with another measure of interference. The results provide initial support that the Portuguese version of the CALIS is a reliable and valid measure for the assessment of the impact of anxiety on child and family functioning.


As perturbações de ansiedade são altamente prevalentes entre crianças em idade escolar. Estas perturbações tendem a seguir um curso crónico e interferem significativamente no funcionamento diário dos jovens. O objetivo principal deste estudo foi examinar as propriedades psicométricas da versão Portuguesa da Escala de Interferência da Ansiedade na Vida da Criança - versões para Pais e Crianças (CALIS-P e CALIS-C). Participaram 132 crianças, com idades entre os 7 e 12 anos, com diagnóstico principal de ansiedade, e seus respetivos pais. A análise fatorial da CALIS-P revelou três fatores que coincidem com as subescalas hipotetizadas: Interferência Em Casa, Fora de Casa e na Vida da Família. Para a CALIS-C, a análise fatorial revelou dois fatores que dizem respeito à Interferência nas Relações Próximas e no Desempenho, que não correspondem às subescalas da versão original. Os estudos psicométricos mostraram uma boa consistência interna para as várias subescalas da CALIS e boas qualidades na validade convergente e divergente. Foi observada ainda uma correlação significativa entre os resultados da CALIS e outra medida de interferência. Estes resultados sugerem que a versão portuguesa da CALIS é uma medida confiável e válida para a avaliação do impacto da ansiedade na criança e no funcionamento familiar.


Assuntos
Humanos , Masculino , Feminino , Criança , Transtornos de Ansiedade/psicologia , Inquéritos e Questionários , Reprodutibilidade dos Testes , Portugal , Psicometria , Atividades Cotidianas/psicologia
3.
Autophagy ; 11(7): 1063-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26046590

RESUMO

Oxidative stress (OS) stimulates autophagy in different cellular systems, but it remains controversial if this rule can be generalized. We have analyzed the effect of chronic OS induced by the parkinsonian toxin paraquat (PQ) on autophagy in astrocytoma cells and primary astrocytes, which represent the first cellular target of neurotoxins in the brain. PQ decreased the basal levels of LC3-II and LC3-positive vesicles, and its colocalization with lysosomal markers, both in the absence and presence of chloroquine. This was paralleled by increased number and size of SQSTM1/p62 aggregates. Downregulation of autophagy was also observed in cells chronically exposed to hydrogen peroxide or nonlethal concentrations of PQ, and it was associated with a reduced astrocyte capability to protect dopaminergic cells from OS in co-cultures. Surprisingly, PQ treatment led to inhibition of MTOR, activation of MAPK8/JNK1 and MAPK1/ERK2-MAPK3/ERK1 and upregulation of BECN1/Beclin 1 expression, all signals typically correlating with induction of autophagy. Reduction of OS by NMDPEF, a specific NQO2 inhibitor, but not by N-acetylcysteine, abrogated the inhibitory effect of PQ and restored autophagic flux. Activation of NQO2 by PQ or menadione and genetic manipulation of its expression confirmed the role of this enzyme in the inhibitory action of PQ on autophagy. PQ did not induce NFE2L2/NRF2, but when it was co-administered with NMDPEF NFE2L2 activity was enhanced in a SQSTM1-independent fashion. Thus, a prolonged OS in astrocytes inhibits LC3 lipidation and impairs autophagosome formation and autophagic flux, in spite of concomitant activation of several pro-autophagic signals. These findings outline an unanticipated neuroprotective role of astrocyte autophagy and identify in NQO2 a novel pharmacological target for its positive modulation.


Assuntos
Astrócitos/patologia , Autofagia/efeitos dos fármacos , Neuroproteção/efeitos dos fármacos , Neurotoxinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Paraquat/toxicidade , Quinona Redutases/metabolismo , Acetilcisteína/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Antioxidantes/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Astrocitoma/patologia , Compostos Benzidrílicos/farmacologia , Inibidores Enzimáticos/farmacologia , Formamidas/farmacologia , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/patologia , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Proteína Sequestossoma-1 , Transdução de Sinais/efeitos dos fármacos , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo
4.
Eur Child Adolesc Psychiatry ; 24(3): 327-37, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25059797

RESUMO

This study explored the agreement and discrepancy between mother and child reports of children's anxiety symptoms and anxiety life interference. A large community sample of 1,065 Portuguese children aged between 7 and 14 years and their mothers completed a DSM-based anxiety symptoms scale. For a subsample of 135 children with an anxiety disorder, additional data on children's anxiety life interference and maternal anxiety and depression symptoms were collected. The results showed that children generally reported higher levels of anxiety symptoms than their mothers. Overall, most correlations between mother and child reports of anxiety symptoms were significant but in the low to moderate range, with the strongest associations for symptoms of specific phobias and school phobia. In the subsample of children with an anxiety disorder, mothers reported higher levels of anxiety life interference than children, and the correlation between mother and child reports of anxiety life interference was significant but again modest in magnitude. Lastly, maternal anxiety was positively associated with the discrepancy between mother and child reports of anxiety symptoms. Together, the results of this study further underline the importance of a multi-informant approach in the evaluation of children's anxiety problems.


Assuntos
Transtornos de Ansiedade/diagnóstico , Ansiedade/diagnóstico , Depressão/diagnóstico , Mães/psicologia , Adolescente , Ansiedade/psicologia , Transtornos de Ansiedade/psicologia , Criança , Depressão/psicologia , Feminino , Humanos , Masculino , Inventário de Personalidade , Escalas de Graduação Psiquiátrica , Autoimagem , Inquéritos e Questionários
5.
Int J Cardiol ; 170(2): 140-5, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24239156

RESUMO

BACKGROUND: Statins are the most commonly prescribed drugs to reduce cardiometabolic risk. Besides the well-known efficacy of such compounds in both preventing and treating cardiometabolic disorders, some patients experience statin-induced side effects. We hypothesize that the use of natural bergamot-derived polyphenols may allow patients undergoing statin treatment to reduce effective doses while achieving target lipid values. The aim of the present study is to investigate the occurrence of an enhanced effect of bergamot-derived polyphenolic fraction (BPF) on rosuvastatin-induced hypolipidemic and vasoprotective response in patients with mixed hyperlipidemia. METHODS: A prospective, open-label, parallel group, placebo-controlled study on 77 patients with elevated serum LDL-C and triglycerides was designed. Patients were randomly assigned to a control group receiving placebo (n=15), two groups receiving orally administered rosuvastatin (10 and 20mg/daily for 30 days; n=16 for each group), a group receiving BPF alone orally (1000 mg/daily for 30 days; n=15) and a group receiving BPF (1000 mg/daily given orally) plus rosuvastatin (10mg/daily for 30 days; n=15). RESULTS: Both doses of rosuvastatin and BPF reduced total cholesterol, LDL-C, the LDL-C/HDL-C ratio and urinary mevalonate in hyperlipidemic patients, compared to control group. The cholesterol lowering effect was accompanied by reductions of malondialdehyde, oxyLDL receptor LOX-1 and phosphoPKB, which are all biomarkers of oxidative vascular damage, in peripheral polymorphonuclear cells. CONCLUSIONS: Addition of BPF to rosuvastatin significantly enhanced rosuvastatin-induced effect on serum lipemic profile compared to rosuvastatin alone. This lipid-lowering effect was associated with significant reductions of biomarkers used for detecting oxidative vascular damage, suggesting a multi-action enhanced potential for BPF in patients on statin therapy.


Assuntos
LDL-Colesterol/sangue , Citrus/química , Fluorbenzenos/administração & dosagem , Hiperlipidemias/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Sinergismo Farmacológico , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hiperlipidemias/epidemiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Fosforilação/efeitos dos fármacos , Placebos , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Risco , Rosuvastatina Cálcica , Receptores Depuradores Classe E/metabolismo , Triglicerídeos/sangue , beta-Ciclodextrinas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...