Efeitos da privação do sono em tarefas cognitivas

Learning and memory are important mechanism for species, since its allows to recognize conspecifics, routes and food place. Sleep is one of behaviors known by facilitate learning, it is a widespread phenomenon, present in most of vertebrates lives and highly investigated in many aspects. It is known that sleep deprivation modifies physiologic behavioral processes in animals, however, sleep function in organism is still debatable. Hypothesis range from energy conservation to memory consolidation, with different roles in animal’s evolution. The zebrafish (Danio rerio) emerg e in the last years as vertebrate model in genetics and developmental biology and quickly become popular in behavioral studies, as learning and memory. Despite the fact that zebrafish is a diurnal animal and have well characterized sleep behavior, zebrafish fish still has advantages due to its small size and low cost of maintenance, whichestablishes this species as interesting model for research on sleep. In this study we aimed to analyze the effects of partial and total sleep deprivation on learning acquisition, as well the concomitant administration of alcohol and melatonin. For this, the research was divided in three phases, each one with a different kind of conditioning: (1) object Recognition, (2) avoidance conditioning and (3) appetitive conditioning. The results showed the fish partially sleep deprived and totally sleep deprived + et hanol could perform the tasks just like the control group, however, fish totally sleep deprived and totally sleep deprived + melatonin showed impairments in attention and memory during the tests. Our results suggest that only one night of sleep deprivation is enough to harm the zebrafish performance in cognitive tasks. In addition, ethanol exposure on the night previously the test seems to suppress the negative effects of sleep deprivation, while the melatonin treatment seems not to be enough to promote sleep state, at least on the protocol applied here.

Efeitos da privação do sono em tarefas cognitivas

Learning and memory are important mechanism for species, since its allows to recognize conspecifics, routes and food place. Sleep is one of behaviors known by facilitate learning, it is a widespread phenomenon, present in most of vertebrates lives and highly investigated in many aspects. It is known that sleep deprivation modifies physiologic behavioral processes in animals, however, sleep function in organism is still debatable. Hypothesis range from energy conservation to memory consolidation, with different roles in animal’s evolution. The zebrafish (Danio rerio) emerg e in the last years as vertebrate model in genetics and developmental biology and quickly become popular in behavioral studies, as learning and memory. Despite the fact that zebrafish is a diurnal animal and have well characterized sleep behavior, zebrafish fish still has advantages due to its small size and low cost of maintenance, whichestablishes this species as interesting model for research on sleep. In this study we aimed to analyze the effects of partial and total sleep deprivation on learning acquisition, as well the concomitant administration of alcohol and melatonin. For this, the research was divided in three phases, each one with a different kind of conditioning: (1) object Recognition, (2) avoidance conditioning and (3) appetitive conditioning. The results showed the fish partially sleep deprived and totally sleep deprived + et hanol could perform the tasks just like the control group, however, fish totally sleep deprived and totally sleep deprived + melatonin showed impairments in attention and memory during the tests. Our results suggest that only one night of sleep deprivation is enough to harm the zebrafish performance in cognitive tasks. In addition, ethanol exposure on the night previously the test seems to suppress the negative effects of sleep deprivation, while the melatonin treatment seems not to be enough to promote sleep state, at least on the protocol applied here.

Controle circadiano e homeostático do sono-virgília em pacientes com acidente vascular encefálico e correlações com a qualidade de vida e o nível de atividade física

The cerebral vascular accident is a neurological dysfunction of vascular origin that leds to development of motor sensibility, cognitive, perceptive and language deficits. Despite the fact that the main sleep disorders in stroke patients are well known, it is still necessary to analyze which mechanisms of regulation of sleep and wakefulness are affected. The objective of this study was to evaluate the changes in the circadian and homeostatic control of sleep-wakefulness in stroke patients and the correlations with quality of life and level of physical activity. The study analyzed 22 stroke patients (55± 12 years old) and 24 healthy subjects (57 ±11 years old). The instruments used in this study were questionnaires on sleep quality, daytime sleepiness, quality of life, physical activity level and the actigraphy. The data were analyzed using the Student `t test, Mann-Whitney test, ANOVA and Spearman's correlation tests. The results showed stability in the sleep-wake circadian expression with changes in the amplitude of the rhythm. However, significant changes were found related to the homeostatic component characterized by increased sleep duration, increased latency, fragmented sleep and lower sleep efficiency. Additional data showed decreased quality of sleep and increased daytime sleepiness, as well as decreased quality of life and level of physical activity. The results indicate that the interaction of circadian and homeostatic control of sleep-wake is compromised and the main reason might be because of the homeostatic component and the lower activity level resulting from the brain damage. Thus, further studies may be developed to evaluate whether behavioral interventions such as increased daytime activity and restriction of sleep during the day can influence the homeostatic process and its relation to circadian component, resulting in improved quality of nocturnal sleep in stroke patients

Funcionalidade em pacientes após acidente vascular encefálico: relação com o sono e ritmo de atividade-repouso

It is known that sleep plays an important role in the process of motor learning. Recent studies have shown that the presence of sleep between training a motor task and retention test promotes a learning task so than the presence of only awake between training and testing. These findings also have been reported in stroke patients, however, there are few studies that investigate the results of this relationship on the functionality itself in this population. The objective of this study was to evaluate the relationship between functionality and sleep in patients in the chronic stage of stroke. A cross-sectional observational study was conducted. The sample was composed of 30 stroke individuals in chronic phase, between 6 and 60 months after injury and aged between 55 and 75 years. The volunteers were initially evaluated for clinical data of disease and personal history, severity of stroke, through the National Institute of Health Stroke Scale, and mental status, the Mini-Mental State Examination. Sleep assessment tools were Pittsburgh Sleep Quality Index, the Questionnaire of Horne and Ostberg, Epworth Sleepiness Scale, the Berlin questionnaire and actigraphy, which measures were: real time of sleep, waking after sleep onset, percentage of waking after sleep onset, sleep efficiency, sleep latency, sleep fragmentation index, mean activity score. Other actigraphy measures were intraday variability, stability interdiária, a 5-hour period with minimum level of activity (L5) and 10-hour period with maximum activity (M10), obtained to evaluate the activity-rest rhythm. The Functional Independence Measure (FIM) and the Berg Balance Scale (BBS) were the instruments used to evaluate the functional status of participants. The Spearman correlation coefficient and comparison tests (Student's t and Mann-Whitney) were used to analyze the relationship of sleep assessment tools and rest-activity rhythm to measures of functional assessment. The SPSS 16.0 was used for analysis, adopting a significance level of 5%. The main results observed were a negative correlation between sleepiness and balance and a negative correlation between the level of activity (M10) and sleep fragmentation. No measurement of sleep or rhythm was associated with functional independence measure. These findings suggest that there may be an association between sleepiness and xii balance in patients in the chronic stage of stroke, and that obtaining a higher level of activity may be associated with a better sleep pattern and rhythm more stable and less fragmented. Future studies should evaluate the cause-effect relationship between these parameters

Estudo da organização funcional do sistema circadiano por meio de ferramentas computacionais e matemáticas

Circadian rhythms are variations in physiological processes that help living beings to adapt to environmental cycles. These rhythms are generated and are synchronized to the dark light cycle through the suprachiasmatic nucleus. The integrity of circadian rhythmicity has great implication on human health. Currently it is known that disturbances in circadian rhythms are related to some problems of today such as obesity, propensity for certain types of cancer and mental disorders for example. The circadian rhythmicity can be studied through experiments with animal models and in humans directly. In this work we use computational models to gather experimental results from the literature and explain the results of our laboratory. Another focus of this study was to analyze data rhythms of activity and rest obtained experimentally. Here we made a review on the use of variables used to analyze these data and finally propose an update on how to calculate these variables. Our models were able to reproduce the main experimental results in the literature and provided explanations for the results of experiments performed in our laboratory. The new variables used to analyze the rhythm of activity and rest in humans were more efficient to describe the fragmentation and synchronization of this rhythm. Therefore, the work contributed improving existing tools for the study of circadian rhythms in mammals

Caracaterização do núcleo pré-geniculado do sagüi (Callithrix jacchus) :projeção retiniana, neuroquímica e atividade celular (expressão de FOS)

In rodents, the suprachiasmatic nucleus (SCN) and the intergeniculate leaflet (IGL) are the main components of the circadian system. The SCN is considerate the site of an endogenous biological clock because can to generate rhythm and to synchronize to the environmental cues (zeitgebers) and IGL has been related as one of the main areas that modulate the action of SCN. Both receive projections of ganglion cells of retina and this projection to SCN is called retinohypothalamic tract (RHT). Moreover, the IGL is connected with SCN through of geniculohypothalamic tract (GHT). In primates (include humans) was not still demonstrated the presence of a homologous structure to the IGL. It is believed that the pregeniculate nucleus (PGN) can be the answer, but nothing it was still proven. Trying to answer that question, the objective of our study is to do a comparative analysis among PGN and IGL through of techniques immunohystochemicals, neural tracers and FOS expression after dark pulses. For this, we used as experimental model a primate of the new world, the common marmoset (Callithrix jacchus). Ours results may contribute to the elucidation of this lacuna in the circadian system once that the IGL is responsible for the transmission of nonphotic information to SCN and participate in the integration between photic and nonphotic stimulus to adjust the function of the SCN. In this way to find a same structure in primates represent an important achieve in the understanding of the biological rhythms in those animals

Avaliação comportamental e neuroquímica de ratos em dessincronização forçada: possíveis implicações para um modelo animal de oscilações no humor

Bipolar disorder has been growing in several countries. It is a disease with high mortality and has been responsible by the social isolation of the patients. Bipolar patients have alterations in circadian timing system, showing a phase shift in various physiological variables. There are several arguments demonstrating alterations in circadian rhythms may be part of the bipolar disorder pathophysiology. Given the necessity for further elucidation, the goal of this study was to validate the forced desynchronization protocol as an animal model for bipolar disorder. To do this, Wistar rats were submitted to a forced desynchronization protocol which consists in a symmetrical light dark cycle with 22h. Under this protocol, rats dissociate the locomotor activity rhythm into two components: one synchronized to the light / dark cycle with 22h, and another component with period longer than 24 hours following the animal endogenous period. These rhythms with different periods sometimes there is coincidence, which we named CAP (Coincidence Active Phase) and the opposite phase, non-coincidence, called NCAP (Non-Concidence Active Phase). The hypothesis is that in CAP animals present a mania-like behavior and animals in NCAP depressive-like behavior. We found some evidence described in detail throughout this thesis. In sum, the animals under forced desynchronization protocol were more stressed, showed an increase in stereotypic behaviors such as grooming and reduction in other behaviors such as risk assessment and vertical exploration when compared to the control group. The CAP animals showed increased locomotor activity, especially during the dark phase when compared to controls (rats under T24) and less depressive behavior in the forced swim test. The animals in NCAP showed a higher anxiety in elevated plus maze, but they don t have ahnedonia. The animals under dissociation have more labeled 5HT1A cells at the amygdala area, which appoint that they have more amygdala inhibition. Taking these data together, we could partially validated the forced desynchronization protocol as an animal model for mood oscillations

A cafeína como agente modulador do ciclo atividade-repouso e memória em saguis (Callithrix jacchus)

Caffeine is the most consumed psychostimulant, with effects on attention, memory, and arousal. But when this substance is ingested near to bedtime there is a decrease on sleep, interfering on mnemonic processes. So, our ain was to investigate how the caffeine ingested near to sleep onset acts on sleep and memory in marmosets. We used 16 adult marmosets, single housed, in a 12:12h light-dark cycle. For registering locomotor activity were used two kinds of sensors. The gyroscope sensor registers activity each 30 sec and detects motion with good accuracy. Because of this we used this sensor for detecting nocturnal activity. The second sensor was based on infrared and accumulates activity each 5 min and it’s not able to detect nocturnal activity, just diurnal activity. We also used camera for registering Rest phase of one marmoset. For the cognitive task, the animals needed to learn a rewarded context (CR) when compared to a non-rewarded context CNR). This experiment comprises 5 phases: 1) Two days of habituation to apparatus; 2)Training for 8 days; 3) oral administration of caffeine (10 mg/kg) or placebo administration ±1h before sleep onset, for 8 days, with marmosets receiving placebo or caffeine; 4) retraining to apparatus and after that, placebo administration (placebo group-GP), or caffeine administration (with continuous group-GC and acute groupGA); 5) Test, for evaluating learning to CR. The sessions were filmed and each one had 8 min of duration. At 7 am started the habituation, training and test sessions, and at 3:15 pm started retraining. The results for gyroscope sensor showed that there was coincidence of 68,57% with nocturnal register of the cameras. Then, the gyroscope sensors detected nocturnal activity for all experimental groups Moreover, when compared sensor gyroscope with sensor based on infrared, was observed that both sensor presented similarity on patterns of activity curve. When we observed the effects of caffeine on Activity-Rest Cycle in GP, GA and GC, is possible to see that that gyroscope sensors and based on infrared presented only intra group differences. As behavioral results, the marmosets learned to discriminate CR when compared to CNR. Moreover, GP presented deficits on memory recall during the test, and GA increased the memory recall, when both were compared to GP. We concluded that the marmosets were able to learning the cognitive task and that the caffeine ingested near to sleep onset acts modulating memory in these animals. Moreover the gyroscope sensor can be used as alternative tool for investigating nocturnal activity. Then, the utilization of this non-invasive device allows marmosets exhibit their behavior within the laboratory conditions as natural as possible.

Da atividade dialógica: aspectos lógicos

CRUZ, Ângela M. P.; Lycurgo, Tassos. Da atividade dialógica: aspectos lógicos. Revista Vivência, Natal, v. 26, p. 51-58, 2004.

Atividade antibacteriana e cicatrizante do óleo de buriti Mauritia flexuosa L

O objetivo deste estudo foi avaliar a atividade antibacteriana in vitro e cicatrizante do óleo de buriti (M. flexuosa) em feridas realizadas em ratos (Rattus norvegicus albinus). Para a avaliação antibacteriana in vitro, foram utilizados cinco patógenos bacterianos incluindo espécies gram-positivas e espécies gram-negativas mediante o uso do método de difusão em ágar. Para a avaliação da atividade cicatrizante, foram utilizados 40 ratos da linhagem Wistar, divididos em dois grupos: o grupo I, composto por 20 ratos com feridas cutâneas, tratados com aplicação tópica do creme base com 10% de óleo de buriti, e o grupo II, controle, com o mesmo número de animais que receberam a aplicação tópica do creme base. A aplicação do produto foi realizada em feridas padronizadas, circulares de 1cm de diâmetro na região dorsolombar. As avaliações clínica, morfométrica e histopatológica das feridas foram realizadas no 3°, 7°, 14° e 21° dias. Em relação à avaliação da atividade antibacteriana, os resultados mostraram que houve inibição do crescimento bacteriano em quatro dos cinco patógenos testados. Em relação à área da ferida, foi observada redução significativa da área no 14o dia e maior percentual de contração das feridas do grupo tratado em relação ao controle. No décimo quarto dia, as feridas tratadas com o óleo do buriti apresentavam aumento significativo na contagem de fibroblastos e fibras colágenas, além de completo processo de reepitelização, enquanto o grupo controle necessitava de mais tempo para resolução do processo cicatricial

Um novo olhar: atividade lúdica como instrumento de integração entre a universidade e escola pública

COSTA, Ivaneide Alves Soares de; Santos, Adriana de Souza; COSTA, Anderson Pereira, et al. Um novo olhar: atividade lúdica como instrumento de integração entre a universidade e escola pública. SEMINÁRIO NACIONAL DO ENSINO MÉDIO, 1. ,2011, Mossoró. Anais... Mossoró: UERN, 2011. p.955 - 965

Impactos sociais da atividade turística: um estudo de caso em Tibau do Sul/RN

This study has been presented for the Master in business of the Universidade Federal do Rio Grande do Norte, the objectives are evaluate the social impacts of the tourism in the community of Tibau do Sul in the state of Rio Grande do Norte. The research is a study of case and the analysis is qualitative and quantitative. The tourism is considerate for many people as an important source of richness, job and an important economic activity. However, for being an activity that involves as main element people, It can cause impacts, could these are beneficial or malign. To evaluate the community's perception about these impacts, it was applied a questionnaire returned to the perceptions of them about the next social indicators: health, job, security, education and life quality. Considering the advent of the tourist activity in a period fifteen year. Through the research could conclude that, of general form the population realizes the changes occurred in the municipal district of positive way. Except for some indicators that receive negative evaluation

Uma cidade em transformação: a influência da atividade do crediário nas mudanças da paisagem urbana de Tenente Ananias-RN

Studies on the urban landscape and on the changes of the urban space are relevant, since they reveal the economic dynamics and the way of life in the cities. Research on small towns, in particular, can display particular aspects and by so doing broaden the comprehension of this theme. The purpose of this research is to analyze the changes in the urban landscape and in the way of life of the inhabitants of the town of Tenente Ananias-RN that have been taking place since the 1990s up to the present (2013) and which result mainly from the commercial activity of crediário. The study is, therefore, a reflection on the impact of crediário economy on the urban landscape and on the way of life of a small town located in the hinterland of the State of Rio Grande do Norte. For this reason, it was necessary to study the landscape and the way of life found in Tenente Ananias in two moments: a) before the rise of the crediário, a period of time ranging from the town‟s initial emergence until the beginning of the 1990s; b) during the progress of crediário activity, from the beginning of the 1990s, when it starts, up to the present (2013). For this research, primary data (interviews, local survey visits) and secondary data (books, articles, reports, census data) were used. As a result of this study, it was possible to conclude that crediário plays a fundamental role for the explanation of the changes taking place in Tenente Ananias-RN, especially in the urban landscape and in the way of life of people. We have attempted, through this research, to contribute to the studies of a historical, social and economic process related to the urban landscape and space of a small town in the State of Rio Grande do Norte

Entre ecos e narcisos: estudo de caso sobre a prática teatral com adolescentes como atividade extracurricular numa escola de nível médio

This masters thesis discusses the studying and the teaching of drama and its implications among teenagers of the contemporary world. This paper also analyses an extracurricular project entitled Drama in the development of citizenship , which was carried out in the public state school Berilo Wanderley in Natal/RN, between 1999 and 2005 with high school students. It comprises a case study that aimed at understanding how and why they chose to take drama classes outside of the school curriculum and even after they graduated, some of them never left the school project and even started participating in the cultural and artistic context of the city of Natal quite actively, both as part of an audience as well as on artistic, political, social and pedagogical performance. The project was high significant for its participants, for the school and for the community, by creating a sense of recognition of the relevance of the pedagogical and artistic production in the public school, as it managed to yield knowledge that helped students to understand the values of group work, sharing information, collaborative assessment and, most of all, to engender actions of protagonism by the teenagers themselves within their social environments. The empirical process developed is placed in a contemporary historical context where educational paradigms shifts occur, and where categories of youth empowerment and protagonism are fundamental to the educational process in the 21st century. The objective of this study is to reflect upon the pedagogical dimension of drama classes for teenagers, aiming at providing further discussions on the role of acting classes in the construction of the personality among youngsters, thus hoping to contribute to other teaching practices, including drama and other subjects of general education