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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Caracteriza??o do ritmo circadiano de atividade e repouso em saguis idosos (Callithrix Jacchus) / Characterization of circadian activity rhythm in aged marmosets (Callithrix jacchus)

Gon?alves, Fabiana Barbosa 01 September 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-07-06T19:40:24Z No. of bitstreams: 1 FabianaBarbosaGoncalves_TESE.pdf: 11151723 bytes, checksum: 742da6ff3b3d6f8fc06c1cfe8e1ba231 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-07-07T17:59:55Z (GMT) No. of bitstreams: 1 FabianaBarbosaGoncalves_TESE.pdf: 11151723 bytes, checksum: 742da6ff3b3d6f8fc06c1cfe8e1ba231 (MD5) / Made available in DSpace on 2016-07-07T17:59:55Z (GMT). No. of bitstreams: 1 FabianaBarbosaGoncalves_TESE.pdf: 11151723 bytes, checksum: 742da6ff3b3d6f8fc06c1cfe8e1ba231 (MD5) Previous issue date: 2015-09-01 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A idade avan?ada pode se tornar um fator limitante para a manuten??o da ritmicidade dos organismos, podendo reduzir a capacidade de gera??o e de sincroniza??o dos ritmos biol?gicos. Neste estudo, foi avaliada a influ?ncia do envelhecimento na express?o da periodicidade end?gena e sincroniza??o (f?tica e social) do ritmo circadiano de atividade (RCA) em um primata diurno, o sagui (Callithrix jacchus). Esse estudo teve dois enfoques: um com abordagem longitudinal, realizado com um sagui macho nas fases adulta (3 anos) e idosa (9 anos) (estudo 1), e o segundo com uma abordagem transversal, com 6 idosos (?: 9,7 ? 2,0 anos) e 11 adultos (?: 4,2 ? 0,8 anos) (estudo 2). A avalia??o da sincroniza??o f?tica envolveu etapas de CE (natural e artificial). No estudo 1, o animal foi submetido ?s seguintes etapas: CE (12:12 ~350:~2 lux), CC (~350 lux) e ressincroniza??o ao CE. No estudo 2, os animais foram avaliados inicialmente em CE natural, e posteriormente na mesma sequ?ncia de condi??es do estudo 1. Durante a etapa de CC no estudo 2, as vocaliza??es di?rias de coespec?ficos mantidos em CE natural na parte externa da col?nia foram consideradas como pista temporal para a sincroniza??o social. O registro da atividade foi realizado automaticamente em intervalos de 5 minutos atrav?s de sensor infravermelho e act?metro, nos estudos 1 e 2, respectivamente. De forma geral, os idosos apresentaram um padr?o de atividade mais fragmentado (> IV, < H e > PSD, ANOVA; p < 0,05), menores n?veis de atividade (ANOVA; p < 0,05) e menor dura??o da fase ativa (ANOVA; p < 0,05) nas condi??es de CE, quando comparados aos adultos. Em CE natural, os idosos apresentaram atraso de fase pronunciado para in?cio e fim da ativa (ANOVA; p < 0,05), enquanto que os adultos apresentaram fase ativa mais ajustada ? fase de claro. Sob CE artificial, houve avan?o de fase e maior ajuste dos hor?rios de in?cio e fim da atividade em rela??o ao CE nos idosos (ANOVA; p < 0,05). Em CC, houve correla??o positiva entre a idade e o per?odo end?geno (t) nos primeiros 20 dias (Correla??o de Pearson; p < 0,05), com o prolongamento do per?odo mantido em dois animais idosos. Nesta condi??o, a maioria dos adultos apresentou ritmo de atividade em livre-curso com t < 24 h nos primeiros 30 dias e posteriormente, coordena??o relativa mediada por pistas auditivas. No estudo 2, a an?lise cross-correlation entre os perfis de atividade dos animais em CC com os animais controle mantidos sob o CE natural, revelou que houve uma menor sincronia social em idosos. Com a resubmiss?o ao CE, a velocidade de ressincroniza??o foi mais lenta nos idosos (teste t; p < 0,05), e para um dos animais idosos houve a perda da capacidade de ressincroniza??o. De acordo com o conjunto de dados, sugere-se que o envelhecimento em saguis pode estar associado ?: 1) menor amplitude e maior fragmenta??o da atividade, acompanhadas de atraso de fase com prolongamento do t, em fun??o de mudan?as na capta??o de pistas f?ticas, na gera??o e na express?o comportamental do RCA; 2) menor capacidade de sincroniza??o f?tica do ritmo de atividade, que pode se tornar mais robusta em condi??es de ilumina??o artificial, possivelmente pelas maiores intensidades luminosas no in?cio da fase ativa devido ?s transi??es abruptas entre as fases de claro e escuro; e 3) menor capacidade de sincroniza??o n?o-f?tica por pistas auditivas de coespec?ficos, possivelmente por redu??o na capta??o sensorial e na resposta dos osciladores circadianos ?s pistas auditivas, podendo tornar o sagui idoso mais vulner?vel e menos adapt?vel ao ambiente, pois estas pistas sociais podem atuar como um importante fator coadjuvante para a sincroniza??o f?tica. / Advanced age may become a limiting factor for the maintenance of rhythms in organisms, reducing the capacity of generation and synchronization of biological rhythms. In this study, the influence of aging on the expression of endogenous periodicity and synchronization (photic and social) of the circadian activity rhythm (CAR) was evaluated in a diurnal primate, the marmoset (Callithrix jacchus). This study had two approaches: one with longitudinal design, performed with a male marmoset in two different phases: adult (three years) and older (9 y.o.) (study 1) and the second, a transversal approach, with 6 old (?: 9.7 ? 2.0 y.o.) and 11 adults animals (?: 4.2 ? 0.8 y.o.) (study 2). The evaluation of the photic synchronization involved two conditions in LD (natural and artificial illuminations). In study 1, the animal was subjected to the following stages: LD (12:12 ~ 350: ~ 2 lx), LL (~ 350 lx) and LD resynchronization. In the second study, the animals were initially evaluated in natural LD, and then the same sequence stages of study 1. During the LL stage in study 2, the vocalizations of conspecifics kept in natural LD on the outside of the colony were considered temporal cue to the social synchronization. The record of the activity was performed automatically at intervals of five minutes through infrared sensor and actimeters, in studies 1 and 2, respectively. In general, the aged showed a more fragmented activity pattern (> IV < H and > PSD, ANOVA, p < 0.05), lower levels of activity (ANOVA, p < 0.05) and shorter duration of active phase (ANOVA, p < 0.05) in LD conditions, when compared to adults. In natural LD, the aged presented phase delay pronounced for onset and offset of active phase (ANOVA, p < 0.05), while the adults had the active phase more adjusted to light phase. Under artificial LD, there was phase advance and greater adjustment of onset and offset of activity in relation to the LD in the aged (ANOVA, p < 0.05). In LL, there was a positive correlation between age and the endogenous period (?) in the first 20 days (Spearman correlation, p < 0.05), with prolonged ? held in two aged animals. In this condition, most adults showed free-running period of the circadian activity rhythm with ? < 24 h for the first 30 days and later on relative coordination mediated by auditory cues. In study 2, the cross-correlation analysis between the activity profiles of the animals in LL with control animals kept under natural LD, found that there was less social synchronization in the aged. With the resubmission to the LD, the resynchronization rate was slower in the aged (t-test; p < 0.05) and in just one aged animal there was a loss of resynchronization capability. According to the data set, it is suggested that the aging in marmosets may be related to: 1) lower amplitude and greater fragmentation of the activity, accompanied to phase delay with extension of period, caused by changes in a photic input, in the generation and behavioral expression of the CAR; 2) lower capacity of the circadian activity rhythm to photic synchronization, that can become more robust in artificial lighting conditions, possibly due to the higher light intensities at the beginning of the active phase due to the abrupt transitions between the light and dark phases; and 3) smaller capacity of non-photic synchronization for auditory cues from conspecifics, possibly due to reducing sensory inputs and responsiveness of the circadian oscillators to auditory cues, what can make the aged marmoset most vulnerable, as these social cues may act as an important supporting factor for the photic synchronization.
2

Vers?o breve da social rhythm metric: um instrumento para avaliar ritmo social de pacientes com acidente vascular cerebral

Fons?ca, Ricardo Diego Rimenez Gurgel da 14 December 2012 (has links)
Made available in DSpace on 2014-12-17T15:16:18Z (GMT). No. of bitstreams: 1 RicardoDRGF_DISSERT.pdf: 820600 bytes, checksum: af0aa8c01c75b607cbe1b519d4628671 (MD5) Previous issue date: 2012-12-14 / Universidade Estadual do Rio Grande do Norte / Stroke is a neurological disorder caused by restriction of blood flow to the brain, which generates directly a deficit of functionality that affects the quality of life of patients. The aim of this study was to establish a short version of the Social Rhythm Scale (SRM), to assess the social rhythm of stroke patients. The sample consisted of 84 patients, of both sexes, with injury time exceeding 6 months. For seven days, patients recorded the time held 17 activities of SRM. Data analysis was performed using a principal components factor analysis with varimax rotation of the full version of SRM in order to determine which activities could compose brief versions of SRM. We then carried out a comparison of hits, the ALI (Level Activity Index) and SRM, between versions, by Kruskal-Walls and the Mann-Whitney test. The Spearman correlation test was used to evaluate the correlation between the score of the full version of SRM with short versions. It was found that the activities of SRM were distributed in three versions: the first and second with 6 activities and third with 3 activities. Regarding hits, it was found that they ranged from 4.9 to 5.8 on the first version; 2.3 to 3.8 in version 2 and 2.8 to 6.2 in version 3, the first the only version that did not show low values. The analysis of ALI, in version 1, the median was 29, in version 2 was 14 and in version 3 was 18. Significant difference in the values of ALI between versions 1 and 2, between 2 and 3 and between versions 1 and 3. The highest median was found in the first version, formed by activities: out of bed, first contact, drink coffee, watch TV in the evening and go to bed. The lowest median was observed in the second version and this was not what had fewer activities, but which had social activities. The medians of the SRM version 1 was 6, version 2 was 4 and version 3 was 6. Significant difference in the values of SRM between versions 1 and 2 and between 2 and 3, but no significant difference between versions 1 and 3. Through analysis, we found a significant correlation only between the full version and the version 1 (R2 = 0.61) (p <0.05), no correlation was found with version 2 (R2 = 0.007) nor with version 3 (R2 = 0.002), this was finally a factor to consider version 1 as the short brazilian version of the Social Rhythm Metric for stroke patients / O Acidente Vascular Cerebral (AVC) ? uma doen?a neurol?gica causada por restri??o da irriga??o sangu?nea cerebral, o que gera de forma direta um d?ficit de funcionalidade que afeta a qualidade de vida dos pacientes. O objetivo desse estudo foi de estabelecer uma vers?o breve da Social Rhythm Scale (SRM), a fim de avaliar o ritmo social dos pacientes com AVC. A amostra foi constitu?da por 84 pacientes, de ambos os sexos, com tempo de les?o superior a 6 meses. Durante sete dias os pacientes registraram a hora em que realizaram 17 atividades da SRM. A an?lise dos dados foi realizada atrav?s de uma an?lise fatorial de componentes principais com rota??o varimax da vers?o completa da SRM, a fim de determinar quais atividades poderiam compor vers?es breves da SRM. Em seguida foi realizada a compara??o dos hits, da ALI (Activity Level Index) e da SRM, entre as vers?es, atrav?s do teste de Kruskal-Walls e do teste de Mann-Whitney. O teste de correla??o de Spearman foi aplicado para avaliar a correla??o entre o escore da SRM da vers?o completa com as vers?es breves. Verificou-se que as atividades da SRM foram distribu?das em tr?s vers?es: a primeira e a segunda com 6 atividades e a terceira com 3 atividades. Em rela??o aos hits, verificou-se que eles variaram de 4,9 a 5,8 na vers?o 1; de 2,3 a 3,8 na vers?o 2 e de 2,8 a 6,2 na vers?o 3, sendo a primeira vers?o a ?nica que n?o apresentou valores baixos. Quanto ? an?lise do ALI, na vers?o 1, a mediana foi de 29; na vers?o 2 de 14 e de 18 na vers?o 3. Foi encontrada diferen?a significativa nos valores do ALI entre as vers?es 1 e 2, entre 2 e 3 e entre as vers?es 1 e 3. A maior mediana foi encontrada na primeira vers?o, formada pelas atividades de: levantar, primeiro contato, beber, tomar caf?, assistir TV ? noite e deitar. A vers?o de menor mediana foi a segunda e esta n?o era a que tinha menos atividades, e sim a que apresentava as atividades sociais. A mediana da SRM na vers?o 1 foi de 6; na vers?o 2 de 4 e de 6 na vers?o 3. Foi encontrada diferen?a significativa nos valores da SRM entre as vers?es 1 e 2 e entre 2 e 3, mas n?o houve diferen?a significativa entre as vers?es 1 e 3. Atrav?s da an?lise realizada, verificou-se uma correla??o significativa somente entre a vers?o completa e a vers?o 1 (R2= 0,61) (p< 0,05), n?o sendo encontrada correla??o com a vers?o 2 (R2= 0,007), nem com a vers?o 3 (R2= 0,002), esse foi enfim um fator determinante para considerar a vers?o 1 como a vers?o breve adequada para o Brasil da escala de ritmo social para pacientes com AVC
3

Efeitos de vocaliza??es de co-espec?ficos e do escuro sobre o ritmo circadiano da atividade motora em sag?is (Callithrix jacchus)

Silva, Crhistiane Andressa da 06 September 2007 (has links)
Made available in DSpace on 2014-12-17T15:36:51Z (GMT). No. of bitstreams: 1 CrhistianeAS.pdf: 3837481 bytes, checksum: 1e934fe40afea6283d1a23747a0954ea (MD5) Previous issue date: 2007-09-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The principal zeitgeber for most of species is the light-dark photocycle (LD), though other environment factors as food availability, temperature and social cues may act. Daily adjustment of the circadian pacemaker may result from integration of environmental photic and non-photic cues with homeostatic cues. Characterization of non-photic effects on circadian timing system in diurnal mammals is scarce in relation to nocturnal, especially for ecologically significant cues. Thus, we analyzed the effect of conspecific vocalizations and darkness on circadian activity rhythm (CAR) in the diurnal primate Callithirx jacchus. With this objective 7 male adults were isolated in a room with controlled illumination, temperature (26,8 ? 0,2?C) and humidity (81,6 ? 3,6%), and partial acoustic isolation. Initially they were under LD 12:12 (~300:2 lux), and subsequently under constant illumination (~2 lux). Two pulses of conspecific vocalizations were applied in total darkness, separated by 22 days, at 7:30 h (external time) during 1 h. They induced phase delays at circadian times (CTs) 1 and 10 and predominantly phase advances at CTs 9 and 15. After that, two dark pulses were applied, separated by 14 days, during 1 h at 7:30 h (external time). These pulses induced phase delays at CTs 2, 3 and 18, predominantly phase advances at CTs 8, 10 and 19, and no change at CT 14. However, marmosets CAR showed oscillations in endogenous period and active phase duration influenced by vocalizations from animals outside the experimental room, which interfered on the phase responses to pulses. Furthermore, social masking and relative coordination with colony were observed. Therefore, phase responses obtained in this work cannot be attributed only to pulses. Afterwards, pulses of conspecific vocalizations were applied in total darkness at 19:00 h (external time), during 1 h for 5 consecutive days, and after 21 days, for 30 consecutive days, on attempt to synchronize the CAR. No animal was synchronized by these daily pulses, although oscillations in endogenous period were observed for all. This result may be due to habituation. Other possibility is the absence of social significance of the vocalizations for the animals due to random reproduction, since each vocalization has a function that could be lost by a mixture of sounds. In conclusion, conspecific vocalizations induce social masking and relative coordination in marmosets CAR, acting as weak zeitgeber / O principal zeitgeber para a maioria das esp?cies ? o ciclo claro-escuro (CE), por?m outros fatores ambientais como disponibilidade de alimento, temperatura e pistas sociais podem atuar. O ajuste di?rio do marcapasso circadiano deve resultar da integra??o de pistas ambientais, f?ticas e n?o-f?ticas, com pistas homeost?ticas. Como a caracteriza??o do efeito de est?mulos n?o-f?ticos sobre o sistema de temporiza??o circadiano em mam?feros diurnos ? escassa em rela??o aos noturnos, principalmente em rela??o a pistas com significado ecol?gico, analisamos o efeito de vocaliza??es de co-espec?ficos e do escuro sobre o ritmo circadiano de atividade motora (RCA) do primata diurno Callithrix jacchus. Com esse objetivo, foram isolados 7 machos adultos em uma sala com ilumina??o, temperatura (26,8 ? 0,2?C) e umidade (81,6 ? 3,6%) controladas e isolamento ac?stico parcial. Inicialmente os animais ficaram sob CE 12:12 (~300:2 lux) e posteriormente sob claro constante (~2 lux). Foram aplicados dois pulsos de vocaliza??es de co-espec?ficos em escuro total, com um intervalo de 22 dias, ?s 7:30 h (hor?rio local) durante 1 h. Esses pulsos desencadearam atrasos de fase nas horas circadianas (HCs) 1 e 10 e predominantemente avan?os de fase nas HCs 9 e 15. Depois foram aplicados dois pulsos de escuro, com um intervalo de 14 dias, ?s 7:30 h (hor?rio local) durante 1 h. Esses pulsos desencadearam atrasos de fase nas HCs 2, 3 e 18, predominantemente avan?os de fase nas HCs 8, 10 e 19, e nenhuma resposta na HC 14. Contudo, o RCA dos sag?is apresentou modula??es no per?odo end?geno e na dura??o da fase ativa por influ?ncia de vocaliza??es emitidas pelos animais de fora da sala, que interferiram nas respostas aos pulsos. Inclusive, foram observados mascaramento social positivo e coordena??o relativa com a col?nia. Portanto, as respostas de fase obtidas nesse trabalho n?o podem ser atribu?das apenas aos pulsos. Posteriormente foram aplicados pulsos de vocaliza??es de co-espec?ficos em escuro total ?s 19 h (hor?rio local), durante 1 h por 5 dias consecutivos, e ap?s 21 dias, por 30 dias consecutivos, para sincronizar o RCA. Nenhum animal sincronizou o RCA aos pulsos di?rios, embora tenham ocorrido modula??es no per?odo end?geno de todos. Esse resultado pode ter sido decorrente de habitua??o ao est?mulo. Outra possibilidade ? a falta de significado social para os animais devido ? reprodu??o aleat?ria das vocaliza??es, visto que cada vocaliza??o tem uma fun??o que pode ter sido perdida com a mistura dos sons. Concluindo, vocaliza??es de co-espec?ficos induzem mascaramento social e coordena??o relativa no RCA de sag?is, atuando como zeitgebers fracos

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