Navegando por Assunto "Eletrofisiologia"

Agora exibindo 1 - 4 de 4

Acesso aberto (Open Access)
Análise comportamental e eletrofisiológica do uso de glicocorticoides no sistema nervoso central em modelos animais de depressão
(Universidade Federal do Pará, 2017-01-31) CARDOSO, Keilla Gisele Mendonça; GOMES, Daniela Lopes; http://lattes.cnpq.br/0014255351015569; LIMA, Silene Maria Araújo de; CV: http://lattes.cnpq.br/8961057812067156
Dexamethasone is a glucocorticoid widely prescribed in Medicine, used as immunosuppressant and anti-inflammatory as well as fluoxetine, which is an antidepressant, serotonin reuptake, which can be used at some point while aiming their respective purposes. The aim of this study was to evaluate the electroencephalographic abnormalities in animals administered with these drugs as well as the behavioral effects evaluated in an animal model of depression, forced swimming. The study was conducted in adult male Wistar rats subjected to administration of dexamethasone acute dose of 4 mg/kg, 24 hours before electrocorticographic record, and chronic, administered for seven days every 24 hours at a dose of 4 mg/kg i.p. Fluoxetine was administered at a dose of 5 mg/kg, for seven days orally with a similar tool the orogastric tube, gavage procedure. After administration, the electroencephalographic parameters of drug activity were recorded and analyzed. When comparing the acute administration of dexamethasone with chronic, there were no statistical differences, but there was a trend towards decreased Theta and Gamma force for chronic use. The group, who received fluoxetine averaged amplitude of 2,661 ± 0,5850 mV²/Hz x 10-3, proving fluoxetine efficacy in controlling depression caused by forced swimming. For the group received dexamethasone chronically and fluoxetine to reverse the power of the middle frame was 0.4758 ± 0.2514 mV²/Hz x 10-3, as there is no statistical difference between the dexamethasone group and dexamethasone fluoxetine, fluoxetine failed to reverse depressive symptoms caused by dexamethasone. In the forced swimming, the fluoxetine group had decreased fluctuation time, mean time of 45.33 ± 23.26 seconds, demonstrating that the group was not depressed. In the group administered with dexamethasone chronic form and assessed the possibility of reversing depressive disorder with fluoxetine immobility time average was 169.8 ± 24.5 seconds indicating that fluoxetine had no effect on the depression caused by chronic application of dexamethasone. We conclude from this study that the glucocorticoid cause changes in electrocorticogram and depression in the forced swimming test (FST). Fluoxetine got no effect on the rats subjected to the FST, after the use of dexamethasone.
Acesso aberto (Open Access)
Desenvolvimento e avaliacao empirica de um simulador educacional para o apoio ao ensino de ECG, baseado na orientacão espacial do coração.
(Universidade Federal do Pará, 2018-09-21) PONTES, Paulo André Ignácio; SERUFFO, Marcos Cesar da Rocha; http://lattes.cnpq.br/3794198610723464; FRANCÊS, Carlos Renato Lisboa; http://lattes.cnpq.br/7458287841862567
The electrocardiogram (ECG) is one of the most commonly used diagnostic procedures in medicine, so it is essential that undergraduate medical students learn to interpret it correctly while they are still in training. Of course, students go through classical learning (ex: lectures and lectures). However, they are generally not efficiently trained in ECG interpretation. In this regard, educational support methodologies and tools in medical practice, such as educational software, should be considered as a valuable approach for medical training purposes. This thesis deals with the development of a simulator (VETOECG) that allows experiential teaching, so that students can relate to projections of the cardiac electrical vectors, through the manipulation of the spatial orientation of the heart and the repercussions in their respective waves in the ECG. In addition, this thesis reports a formal experiment (pre / posttest with a randomized control group) to evaluate empirically the learning effetiveness of the tool and analyzes the subjective factors of students' perception regarding motivation, user experience and collected through questionnaires. The results indicated that the simulator has positive learning efficacy compared to traditional methodologies (statistically significant difference, p-value <0.0001 *, median of 38.5 points and interquartile range 23.1 to 46.2 points) used for learning in the proposed study. It can be verified that the simulator is adequate in the most diverse dimensions, since they were evaluated positively: in terms of motivation (88.15%), user experience (76%) and learning (96.5%).
Acesso aberto (Open Access)
Potencial cortical provocado visual pseudoaleatório gerado por estímulos compostos: efeito do modo de apresentação e do tempo de adaptação da resposta
(Universidade Federal do Pará, 2016-09-28) RISUENHO, Bárbara Begot Oliveira; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718
Conventional pattern-reversal visual evoked cortical potential (VECP) shows positivity for luminance and chromatic equiluminant stimuli while conventional pattern-onset VECP shows positivity for luminance pattern-onset and negativity for chromatic pattern-onset. We evaluated how the presentation mode affects VECPs elicited by luminance and compound (luminance plus chromatic) pseudo-random stimulation. Eleven normal trichromats and 17 red-green color-blinds were studied. Pattern-reversal and pattern-onset luminance and compound (luminance plus red-green) gratings were temporally modulated by m-sequence. We used a cross-correlation routine to extract the first order kernel (K1) and the first and second slices of the second order kernel (K2.1 and K2.2, respectively) from the VECP response. We integrated the amplitude of VECP components as a function of time in order to estimate its magnitude for each stimulus condition. We also used a normalized cross-correlation method in order to test the similarity of the VECP components. In order to assess how the interection time afects the VECP’s amplitude we calculate de root mean square (RMS) amplitude into differents time windows and correlated it with the response time interval relative to the sencond order kernel slice avaliated. The VECP components varied with the presentation mode and the presence of red-green contrast in the stimuli. In trichromats, for compound conditions, pattern-onset K1, K2.1, and K2.2, and pattern-reversal K2.1 and K2.2 had negative-dominated waveforms at 100 ms. Small negativity or small positivity were observed in dichromats. Trichromats had larger VECP magnitude than color-blinds for compound pattern-onset K1 (with large variability across subjects), compound pattern-onset and pattern-reversal K2.1, and compound pattern-reversal K2.2. Trichromats and color-blinds had similar VECP amplitude for compound pattern-reversal K1 and compound pattern-onset K2.2, as well as for all luminance conditions. The cross-correlation analysis showed high similarity between waveforms of compound pattern-onset K2.1 and pattern-reversal K2.2 as well as pattern-reversal K2.1 and K2.2. The amplitude of VECP was smaller as higher was the response time interval. We suggest that compound pattern-reversal K2.1 is an appropriate response to study red-green color-opponent activity.
Acesso aberto (Open Access)
Teste de equivalência e exame eletrofisiológico em pessoas acometidas por acidente vascular cerebral com e sem comprometimento cognitivo.
(Universidade Federal do Pará, 2017-01-27) PARANHOS, Alna Carolina Mendes; SOUZA, Givago da Silva; http://lattes.cnpq.br/5705421011644718; https://orcid.org/0000-0002-4525-3971; PARACAMPO, Carla Cristina Paiva; http://lattes.cnpq.br/9018003546303132
Stroke is a neurological dysfunction caused by an abnormality in the cerebral circulation. About 30% of the victims will present cognitive impairment three months after the injury and 10% some type of dementia. In the area of Neuroscience and Behavior, studies have suggested that the N400 component is activated both in semantic choice tasks and in equivalence tests. The present study aimed (1) to study the learning of conditional relations and equivalence test in stroke survivors with and without cognitive impairment and (2) to verify the occurrence and quality of the N400 component in diferent stimuli conditions with the presentation of equivalent and non-equivalent pairs, before and after training of conditional relations and equivalence test. Eighteen participants (nine in each study) distributed into three groups - Control Group (GC), composed of healthy adults; And two Experimental Groups, stroke patients without cognitive impairment (GE1) and patients with cognitive impairment (GE2). In Study 1, all participants were exposed to a training structure of arbitrary conditional relations AB, AC and AD, and subsequent equivalence test. Study 2 was identical to Study 1 regarding the conditional teaching protocol used, the difference was in the event-related potential records in the participants, before and after the equivalence method. The results of Study 1 and 2 suggest that the teaching protocol used was effective in establishing arbitrary conditional relations and equivalence classes for GC and GE1 participants but not effective for participants in GE2. In Study 2, the occurrence of the N400 component was ob served in the four stimulation conditions in the event-related potential records of the Participants P21 (GC), P23 (GC) and P24 (GE1), in the Participant P26 (GE1) in three stimulation conditions and in Participants P27 (GE2) and P29 (GE2) in none of the four stimulation conditions. The results suggest a direct relation between the degree of learning of conditional relations and the formation of equivalence classes with the occurrence and quality of the N400 component. The present study extends the analyzes of this correlation when conducting the experiments with a population of stroke, with and without cognitive impairment, having great applicability in the context of cognitive evaluation and rehabilitation.