ABSTRACT
Asthma is an inflammatory condition characterized by the involvement of several mediators, including reactive oxygen species. The aim of the present study was to investigate the superoxide release and cellular glutathione peroxidase (cGPx) activity in peripheral blood granulocytes and monocytes from children and adolescents with atopic asthma. Forty-four patients were selected and classified as having intermittent or persistent asthma (mild, moderate or severe). The spontaneous or phorbol myristate acetate (PMA, 30 nM)-induced superoxide release by granulocytes and monocytes was determined at 0, 5, 15, and 25 min. cGPx activity was assayed spectrophotometrically. The spontaneous superoxide release by granulocytes from patients with mild (N = 15), moderate (N = 12) or severe (N = 6) asthma was higher at 25 min compared to healthy individuals (N = 28, P < 0.05, Duncan test). The PMA-induced superoxide release by granulocytes from patients with moderate (N = 12) or severe (N = 6) asthma was higher at 15 and 25 min compared to healthy individuals (N = 28, P < 0.05 in both times of incubation, Duncan test). The spontaneous or PMA-induced superoxide release by monocytes from asthmatic patients was similar to healthy individuals (P > 0.05 in all times of incubation, Duncan test). cGPx activity of granulocytes and monocytes from patients with persistent asthma (N = 20) was also similar to healthy individuals (N = 10, P > 0.05, Kruskal-Wallis test). We conclude that, under specific circumstances, granulocytes from children with persistent asthma present a higher respiratory burst activity compared to healthy individuals. These findings indicate a risk of oxidative stress, phagocyte auto-oxidation, and the subsequent release of intracellular toxic oxidants and enzymes, leading to additional inflammation and lung damage in asthmatic children.
Subject(s)
Humans , Male , Female , Child , Adolescent , Asthma/blood , Glutathione Peroxidase/metabolism , Granulocytes/enzymology , Monocytes/enzymology , Superoxide Dismutase/biosynthesis , Asthma/enzymology , Biomarkers/blood , Case-Control Studies , Chronic Disease , Time FactorsABSTRACT
O glaucoma experimental foi produzido em animais como coelho e macaco na tentativa de explicar os mecanismos da doença. Modelos de glaucoma espontâneo também foram descritos. No presente trabalho a elevaçäo da pressäo intraocular (PIO) foi produzida em 12 cäes por hemácia autóloga fixada em glutaraldeído injetada na câmara anterior do olho esquerdo, sob microscópio cirúrgico. O olho direito foi o controle. Tonometria pelo Schiotz foi realizada a cada 24 horas com o animal em posiçäo sentada. Com intervalos de tempo que variavam de 2 a 20 dias após a injeçäo os animais foram sacrificados, os olhos enucleados e congelados, medidos os diâmetros sagital e transversal e entäo fixados em soluçäo de formol a 10 por cento e os cortes corados pela hematoxilina-eosina para exame histológico. Em todos os animais a PIO foi maior quando comparado com os controles, o mesmo acontecendo com a medida dos diâmetros que foram também maiores. Os achados histológicos foram compatíveis com glaucoma
Subject(s)
Animals , Dogs , GlaucomaABSTRACT
O glaucoma congenito e uma das principais causas de cegueira na infancia. A suspeita diagnostica pode ser estabelecida por todos aqueles que cuidam da crianca desde o seu nascimento. O tratamento deve ser precoce e sempre e cirurgico. O tratamento da ambliopia, presente nestas criancas, deve ser sempre considerado