RESUMO
OBJECTIVES: Paraquat (PQ) is a widely used herbicide. Exposure to PQ at toxic doses can result in fatal acute lung injury. Inhibition of the poly-(ADP-ribose) polymerase (PARP) enzyme alleviates inflammation and necrosis in various pathologies. Here we aimed to evaluate the effects of PARP inhibition on PQ-induced lung damage in a rat experimental model. METHODS: Female Sprague-Dawley rats (n = 24) were allocated into three groups: sham, PQ and PQ + 3-aminobenzamide (3-AB) that is a PARP inhibitor, groups. Experimental lung injury was induced by administration of 15 mg/kg PQ intraperitoneally in PQ and PQ + 3-AB groups. 3-AB (10 mg/kg twice per day) was administered to the PQ + 3-AB group for four consecutive days. The animals were killed on the fifth day following PQ administration. Lung tissue and blood samples were collected and stored until analysis. RESULTS: Serum lactate dehydrogenase (LDH) and neopterin levels, tissue oxidative stress parameters, transforming growth factor-beta1 (TGF-ß) levels and histological injury scores in the PQ + 3-AB group were significantly lower than in the PQ group (P < 0.05, PQ vs. PQ + 3-AB). Total antioxidant capacity in the PQ + 3-AB group was significantly higher than in the PQ group (P < 0.05, PQ + 3-AB vs. PQ). CONCLUSION: Our results suggested that the use of PARP inhibitors following PQ toxicity might be useful for minimizing lung injury due to paraquat toxicity.
Assuntos
Benzamidas/uso terapêutico , Lesão Pulmonar/prevenção & controle , Paraquat/toxicidade , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Poli(ADP-Ribose) Polimerases/metabolismo , Animais , Antioxidantes/metabolismo , Benzamidas/administração & dosagem , Biomarcadores/sangue , Modelos Animais de Doenças , Feminino , Injeções Intraperitoneais , Peroxidação de Lipídeos/efeitos dos fármacos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/enzimologia , Lesão Pulmonar/patologia , Neopterina/sangue , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Ratos Sprague-DawleyRESUMO
In this study, singular spectrum analysis (SSA) has been used for the first time in order to extract emotional features from well-defined electroencephalography (EEG) frequency band activities (BAs) so-called delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-16 Hz), beta (16-32 Hz), gamma (32-64 Hz). These five BAs were estimated by applying sixth-level multi-resolution wavelet decomposition (MRWD) with Daubechies wavelets (db-8) to single channel nonaveraged emotional EEG oscillations of 6 s for each scalp location over 16 recording sites (Fp1, Fp2, F3, F4, F7, F8, C3, C4, P3, P4, T3, T4, T5, T6, O1, O2). Every trial was mediated by different emotional stimuli which were selected from international affective picture system (IAPS) to induce emotional states such as pleasant (P), neutral (N), and unpleasant (UP). Largest principal components (PCs) of BAs were considered as emotional features and data mining approaches were used for the first time in order to classify both three different (P, N, UP) and two contrasting (P and UP) emotional states for 30 healthy controls. Emotional features extracted from gamma BAs (GBAs) for 16 recording sites provided the high classification accuracies of 87.1% and 100% for classification of three emotional states and two contrasting emotional states, respectively. In conclusion, we found the followings: (1) Eigenspectra of high frequency BAs in EEG are highly sensitive to emotional hemispheric activations, (2) emotional states are mostly mediated by GBA, (3) pleasant pictures induce the higher cortical activation in contrast to unpleasant pictures, (4) contrasting emotions induce opposite cortical activations, (5) cognitive activities are necessary for an emotion to occur.
Assuntos
Ondas Encefálicas/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Reconhecimento Facial/fisiologia , Adulto , Mapeamento Encefálico/métodos , Mineração de Dados/métodos , Eletroencefalografia/métodos , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Análise de Componente Principal , Análise de Ondaletas , Adulto JovemRESUMO
In this study, binocular interaction in guinea pigs is evaluated using bioelectrical activities. A difference potential, as evidence of an interaction, is calculated by subtracting the sum of visual-evoked potentials recorded by left and right monocular visual stimulations from the potential recorded by binocular stimulation. A negative monophasic wave with an average amplitude of 15.1 microV and an average latency of 106 ms is observed in the difference potential. This finding implies that the P100 is the main guinea pig visual-evoked potential wave that is affected by binocular interaction. Binocular interaction is also observed in the waves N75 and N140, although with a smaller amplitude. No interaction is observed in the segments of P55 and P200 waves.
Assuntos
Potenciais Evocados Visuais/fisiologia , Visão Binocular/fisiologia , Córtex Visual/fisiologia , Animais , Lateralidade Funcional/fisiologia , Cobaias , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Visão Monocular/fisiologia , Vias Visuais/fisiologiaRESUMO
Neurophysiological studies aiming to explore how the brain integrates information from different brain regions are increasing in the literature. The aim of the present study is to explore intramodal (binaural, binocular) and intermodal (audio-visual) interactions in the guinea pig brain through the observation of changes in evoked potentials by generalized continuous background activity. Seven chronically prepared animals were used in the study and the recordings were made as they were awake. Epidural electrodes were implanted to the skulls by using stereotaxic methods. Continuous light for retinal or continuous white noise for cochlear receptors were used as continuous conditioning stimuli for generalized stimulation. To evoke auditory or visual potentials, click or flash were used as transient imperative stimuli. The study data suggest that (a) white noise applied to one ear modifies the response to click in the contralateral ear which is a binaural interaction; (b) continuous light applied to one eye modifies the response to flash applied to the contralateral eye which is interpreted as a binocular interaction; (c) regardless of the application side, white noise similarly modified the response to flash applied to the either eye connoting a nonspecific effect of white noise on vision, independent from spatial hearing mechanisms; (d) on the other hand, continuous light, in either eye, did not affect the response to click applied to any ear, reminding a 'one-way' interaction that continuous aural stimulation affects visual response.