Bibliografia

Experiência Comprovada / Projetos de Clientes


Actigraphy-based evaluation of sleep quality and physical activity in individuals with spinal cord injury
Abstract: Sleep disturbances are frequently reported by individuals with spinal cord injury (SCI) and are associated both with poor quality of life and reduced ability to participate in rehabilitation and daily life activities.
Ver mais..

Avaliação da Qualidade do Sono na Perspectiva do Conforto para o Pós-Graduando em Enfermagem
Abstract: O sono é considerado fundamental para o ser humano, pois possui função restaurativa. Rupturas no ritmo circadiano afetam o desempenho cognitivo e representam fator de risco para diversas doenças crônicas. Este problema torna-se ainda mais frequente entre trabalhadores da área da saúde e estudantes universitários, devido a múltiplos fatores ambientais que podem influenciar diretamente seu comportamento de sono-vigília 
Ver mais..

Avaliação do padrão de sono dos estudantes de medicina da Escola Multicampi de Ciências Médicas do Rio Grande do Norte / Sleep pattern evaluation in medical students at Medical Sciences Multicampi School of Rio Grande do Norte
Abstract: Distúrbios do sono são comuns em estudantes de medicina e podem causar prejuízos na formação acadêmica. As demandas curriculares tendem a dessincronizar o ciclo sono-vigília e alterar a qualidade do sono, e por vezes obrigar que os estudantes optem entre manter a regularidade do padrão de sono ou atender às exigências acadêmicas. O presente trabalho avaliou o padrão de sono dos estudantes de medicina da Escola Multicampi de Ciências Médicas do Estado do Rio Grande do Norte, situada no município de Caicó-RN, cujo currículo adotado fundamenta-se na Aprendizagem Baseada em Problemas (Problem Based Learning – PBL).
Ver mais..

Biomechanical procedure to assess sleep restriction on motor control and learning
Abstract: The analysis of sleep quality during long periods and its impact on motor control and learning performance are crucial aspects for human health. The aim of this study is to analyze effects of chronic sleep restriction on motor performance. It is intended to establish motor control indicators in sleep quality analysis. A wearable actigraphy that records accelerometry, ambient light, and body temperature was used to monitor the sleep habits of 12 healthy subjects for two weeks before performing motor control and learning tests. 

Ver mais..

Baseline Pupil Diameter Is Not a Reliable Biomarker of Subjective Sleepiness

Abstract: Sleepiness is commonly seen as reflecting the basic physiological need to sleep and is associated with physiological and neurobiological changes. Subjective evaluations of sleepiness, however, are neither representative of cognitive and physical performances, nor of physiological sleepiness. Finding a simple, rapid, and objective marker of sleepiness is essential in order to prevent errors and accidents, but this has remained largely unsuccessful. The aim of this study was to determine whether the baseline pupil diameter is a physiological biomarker of sleepiness at all times of day and to isolate the regulatory components involved.
Ver mais..

Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults

Abstract: The lack of sleep, both in quality and quantity, is an increasing problem in modern society, often related to workload and stress. A number of studies have addressed the effects of acute (total) sleep deprivation on postural control. However, up to date, the effects of chronic sleep deficits, either in quantity or quality, have not been analyzed.
Ver mais..

Ciclos de atividade/repouso e alimentação/jejum associados ao uso de equipamentos eletrônicos: aspectos comportamentais e padrões temporais

Abstract: A energia elétrica de uso doméstico no cenário mundial é um fenômeno recente que incorporou modulações temporais na expressão dos ritmos biológicos, como os hábitos alimentares e de sono. Após sua popularização, tecnologias eletrônicas foram criadas e incorporadas às nossas rotinas diárias. O acesso à iluminação elétrica promove uma maior flexibilidade na organização temporal das nossas atividades por facilitar o controle de extensão da fase de atividade para horas mais tardias da noite. Assim, essa situação pode constituir um desafio temporal ao organismo, gerado pelas oscilações das pistas temporais, adiantando ou atrasando a ocorrência de eventos rítmicos como a alimentação/jejum, atividade/repouso e metabolismo.
Ver mais..

Circadian Light Exposures of Shift Working Nurses
Abstract: Studies have linked adverse health outcomes to work during the body’s subjective night. Certain shift schedules result in light exposure profiles that may cause circadian disruption. Previous studies estimated average artificial illuminance to quantify light at night (LAN) at work which limits their validity and scope. However, daylight, shift length, commuting exposures and light during restricted sleep opportunities compete with LAN as causative agents, as do non-photic factors such as social disruption, activity and food intake during the subjective night. Investigations into the effects of light in shift work should be supported by 24-hour light exposure measurements, e.g. to establish dose-response relationships. The purpose of the study was to collect and suggest interpretations of 24-hour exposure data, and investigate both daytime and night-time workers’ light cycles in more detail.
Ver mais..

Circadian ontogeny through the lens of nonparametric variables of actigraphy
Abstract: Studies focusing on human rhythmicity show that human circadian rhythm suffers constant changes across lifespan. Changes in rest-activity patterns can be studied through nonparametric variables of actigraphy: L5 (an individual’s least active 5 h), M10 (an individual’s most active 10 h) and RA (relative amplitude of the rest-activity rhythm). The variable RA is the normalized difference between L5 and M10 – the higher the RA, the greater the difference between these two variables.
Ver mais..

Circadian rhythm abnormalities and autonomic dysfunction in patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

Abstract: Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) patients frequently show autonomic symptoms which may be associated with a hypothalamic dysfunction. This study aimed to explore circadian rhythm patterns in rest and activity and distal skin temperature (DST) and their association with self-reported outcome measures, in CFS/ME patients and healthy controls at two different times of year.
Ver mais..

Comparison between an African town and a neighbouring village shows delayed, but not decreased, sleep during the early stages of urbanisation

Abstract: The well-established negative health outcomes of sleep deprivation, and the suggestion that availability of electricity may enable later bed times without compensating sleep extension in the morning, have stimulated interest in studying communities whose sleep pattern may resemble a pre-industrial state. Here, we describe sleep and activity in two neighbouring communities, one urban (Milange) and one rural (Tengua), in a region of Mozambique where urbanisation is an ongoing process. The two communities differ in the amount and timing of daily activity and of light exposure, with later bedtimes (≈1 h) associated with more evening and less daytime light exposure seen in the town of Milange.
Ver mais..

Comparison of sleep parameters assessed by actigraphy of healthy young adults from a small town and a megalopolis in an emerging country
Abstract: The analysis of sleep quality and its impact on diurnal sleepiness is a crucial aspect of human health. Modern life in large cities compels people to spend less hours sleeping than they need. A wearable actigraphy that records accelerometry, light and body temperature was used to register the sleep habits of 54 healthy subjects for 14 days. From them, 28 participants resided in a town that could be regarded as a rural environment while the other subjects lived in the largest metropole of South America. The subjects filled three questionnaires to assess sleep quality (Pittsburgh Sleep Quality Index – PSQI), sleepiness (Epworth Sleepiness Scale – ESS) and chronotype (Morningness-Eveningness Questionnaire – MEQ-HO). 

Ver mais..

Comparison of sleep quality assessed by actigraphy and questionnaires to healthy subjects
Abstract: Sleep quality analysis is crucial for human health and it is related to duration, rhythm and quality. The goal of this study is to analyze objective assessment of the sleep-wake cycles with actigraphy, subjective questionnaires and their relationship with sleep quality indices. A wearable actigraph registered the sleep habits of 41 healthy subjects for 9 days. Afterwards, the subjects filled two questionnaires about sleep quality (Pittsburgh Sleep Quality Index) and sleepiness (Epworth Sleepiness Scale). The subjects were divided into two groups based on cut-off scores and the actigraphy parameters were compared between groups. Group 1 in ESS and PSQI categorization had less diurnal sleepiness and better sleep quality, respectively, than Group 2. Measurements of regularity (IS), fragmentation (IV), active phase amplitude (M10), rest amplitude (L5), and relative amplitude (RA) were compared between groups. Group 2 had higher L5 values. Parameter L5 (lowest of 5 consecutive hours of activity) was concluded to be relevant to identify the sleep conditions of the subjects.
Ver mais..

Comportamento, fluência verbal e ritmos circadianos em indivíduos com o Transtorno do Espectro do Autismo (TEA) antes e após o uso de melatonina

Abstract: As características comuns ao quadro do Transtorno do Espectro do Autismo (TEA) destacadas pelo DSM-5 são: déficit de comunicação, dificuldade em fazer amizades ou se relacionar, dependência de rotina, resistência a mudanças e obsessão por itens inapropriados. Tais comportamentos podem ser observados desde a infância, porém com variações em cada indivíduo, o que levou o TEA a ser considerado um “continuum” que varia de menos comprometido (leve) a muito comprometido (grave). Dentre a complexa sintomatologia do TEA nos diferentes graus destaca-se a alta prevalência de distúrbios de sono, com influência negativa nas alterações comportamentais, instabilidade de humor, déficits nas funções neurocognitivas, incluindo memória, atenção, criatividade verbal, flexibilidade cognitiva e raciocínio abstrato.
Ver mais..

Daytime sleepiness affects gait auditory synchronization ability
Abstract: Sleep disturbances in modern life lead to cognitive and motor performance impairments in everyday tasks such as gait. The most common symptom of these disturbances is daytime sleepiness, which can be assessed by questionnaires such as the Epworth Sleep Scale (ESS). The ESS evaluates sleep health and daytime dysfunction. The goal of this study is to assess the influence of sleepiness on a motorauditory synchrony task, rhythmed gait. High and low sleepiness clusters were formed based on the participants ESS scores. 

Ver mais..

Efeito da alternância dos turnos de trabalho sobre o consumo alimentar de trabalhadores rodiziantes
Abstract: Estudos têm descrito hábitos alimentares não saudáveis e horários de refeições irregulares entre trabalhadores em turnos. Entretanto, o impacto da rotação entre os horários de trabalho diurno, vespertino e noturno e os dias livres, dentro de um curto período de tempo, no padrão de consumo alimentar é pouco abordado na literatura. Objetivo: Avaliar o efeito da rotação de turnos na duração do consumo alimentar, do inglês “eating duration” (ED), assim como o efeito da duração do consumo alimentar na ingestão de energia e macronutrientes.
Ver mais..

Efeito da ingestão de uma refeição hiperproteica durante o turno noturno sobre a resposta metabólica pós-prandial no dia seguinte: um estudo crossover, randomizado e controlado
Abstract: O trabalho em turnos tem sido associado com doenças nutricionais e metabólicas, sendo que a qualidade, a quantidade e o horário da alimentação são considerados fatores importantes associados ao desenvolvimento de doenças crônicas e ganho de peso em trabalhadores em turnos. No entanto, o impacto da alimentação noturna na resposta metabólica dos trabalhadores em turnos é pouco explorado na literatura. Objetivo: Avaliar o efeito agudo de uma refeição hiperproteica em comparação com uma refeição normoproteica servidas à noite na resposta metabólica pós-prandial de trabalhadores noturnos no dia seguinte.
Ver mais..

El temps biològic. Els ritmes circadiaris i les seves implicacions en la salut
Abstract: En el curs de l’evolució els éssers vius s’han hagut d’adaptar als canvis cíclics generats pels moviments de la Terra i, en conseqüència, presenten variacions diàries en la seva fisiologia i conducta. Els ritmes circadiaris de tots els òrgans i cèl·lules de l’organisme estan en perfecta sincronia produint una estructura orgànica ben definida en el temps. La ciència que estudia els ritmes biològics és la cronobiologia. La principal estructura que regula els ritmes circadiaris en els mamífers són els nuclis supraquiasmàtics, un conjunt de neurones a la base del cervell. La preferència de les persones a triar un horari determinat, el cronotip, ve donada per la genètica del rellotge intern, per l’edat i per la llum. Quan per determinades circumstàncies el rellotge intern es desajusta del temps extern es parla de desajust circadiari. La causa més típica de desajust circadiari són els treballs nocturns a torns, però també pot produir-se per il·luminació anòmala o per poca regularitat horària. El desajust circadiari és un risc per a la salut, i pot comportar més incidència d’alteracions metabòliques, com ara diabetis, malalties cardiovasculars i alteracions del son i la cognició.
Ver mais..

Evaluating the efficacy of Internet-Based Exercise programme Aimed at Treating knee Osteoarthritis (iBEAT-OA) in the community: a study protocol for a randomised controlled trial
Abstract: Knee osteoarthritis (OA) is the most common joint disease worldwide. As of today, there are no disease-modifying drugs, but there is evidence that muscle strengthening exercises can substantially reduce pain and improve function in this disorder, and one very well tested physiotherapy protocol is the ‘Better Management of Patients with Osteoarthritis’ developed in Sweden. Given the high prevalence of knee OA, a potentially cost-effective, digitally delivered approach to treat knee OA should be trialled. This study aims to explore the benefits of iBEAT-OA (Internet-Based Exercise programme Aimed at Treating knee Osteoarthritis) in modulating pain, function and other health-related outcomes in individuals with knee OA.

Ver mais..

Melatonin and circadian rhythms in autism: Case report
Abstract: Among the most co-occurring conditions in autism spectrum disorders (ASD), there are sleep disorders which may exacerbate associated behavioral disorders and lead to intensification of existing autistic symptoms. Several studies investigating the use of melatonin in the treatment of sleep disorders in ASD have shown comparative efficiency in sleep with little or no side effects. Here we report a case of ASD with non-24-hour rhythm and the effect of melatonin in circadian parameters by actigraphy. Visual analysis of the first 10 days recorded and the periodogram suggest that this patient showed a non-24-hour rhythm. This ASD subject showed before melatonin administration an activity/rest rhythm lower than 24 hours.
Ver mais..

Modification of a personal dosimetry device for logging melanopic irradiance
Abstract: Performance characterisations were carried out before and after a modification to the optics of the Condor Instruments’ ActTrust light and activity data loggers to improve the spectral performance for measuring melanopic-weighted irradiance in non-visual studies. The results confirm the intended improvement, so that the device provides the best-known single-sensor match to the melanopic response. In addition, the device includes a separate sensor which remained well-matched for illuminance logging.

Ver mais..

Nocturnal motor activity and light exposure: Objective actigraphy-based marks of melancholic and non-melancholic depressive disorder. Brief report
Abstract: Differentiation of melancholic (MEL) and non-melancholic (N-MEL) depression results from subjective assessment of psychomotor disturbance, which obscures their accurate diagnosis. CORE instrument assigned participants with severe or refractory depression to MEL or N-MEL group. Participants underwent 7 days of actigraphy. Data was fitted to a cosinusoidal curve corresponding to a 24-h rhythm. Nocturnal activity was significantly higher in N-MEL. ROC curve shows that average night activity discriminate participants with 71% sensitivity and 100% specificity (area under the curve = 0.84). Actigraphy contribute to the objective differentiation of depression subtypes, and have implications for research on their neurobiology and clinical management.

Ver mais..

Non-visual effects of light: How to use light to promote circadian entrainment and elicit alertness

Abstract: In addition to stimulating the visual system, light incident on the retina stimulates other biological functions, also referred to as non-visual responses. Among the most notable biological functions are human circadian rhythms, which are bodily rhythms that, in constant darkness, oscillate with a period close to, but typically slightly longer than 24 hours. Twenty-four-hour light–dark patterns incident on the retina are the major synchroniser of circadian rhythms to the local time on Earth. Entrainment of circadian rhythms has been implicated in health and well-being. Light can also elicit an acute alerting effect on people, similar to a ‘cup of coffee.’ This review summarises the literature on how light affects entrainment and alertness and how it can be used to achieve these aims.

Ver mais..

Optical performance characterization of light-logging actigraphy dosimeters

Abstract: There are several wearable products specially developed or marketed for studying sleep, circadian rhythms, and light levels. However, new recommendations relating to human physiological responses to light have changed what measurements researchers may demand. The performances of 11 light-logging dosimeters from eight manufacturers were compared. The directional and spectral sensitivities, linearity, dynamic range, and resolution were tested for seven models, and compared along with other published data. The sample mainly comprised light-logging actigraphy dosimeters wearable as badges, in accordance with measurement protocols for larger-scale field studies. A proposed standard for optical performance assessments is set out.

Ver mais..

Projeto e construção de um dispositivo de medição de luminosidade e temperatura para o estudo de ritmos biológicos humanos

Abstract: Esse trabalho apresenta a concepção, projeto e construção de um dispositivo para realizar medições ligadas ao estudo sobre a alteração dos ritmos biológicos humanos em exposição prolongada à iluminação artificial. A coleta de dados inclui a luminosidade e temperatura de um ambiente hospitalar, atendendo aos critérios propostos para sua utilização em um projeto de pesquisa do Hospital de Clínicas de Porto Alegre. Os sensores desses parâmetros ambientais são ligados a dois tipos de microcontroladores, ambos capazes de armazenar e transmitir os resultados para posterior análise.
Ver mais..

Relação entre o nível de conhecimento sobre o sono e os hábitos e qualidade de sono, e os componentes da atenção em universitários
Abstract: O atraso de fase do sono, caracterizado por horários mais tardios de dormir e acordar, visto na adolescência, pode persistir após o ingresso dos jovens na universidade. Esse atraso resulta no encurtamento da duração do sono dos estudantes que estudam pela manhã, uma vez que são obrigados a adiantar o horário de acordar na semana letiva. Esse comportamento pode modificar os hábitos e qualidade de sono e assim, ocasionar prejuízo na atenção daqueles do turno matutino. Sabendo que a atenção é um processo básico capaz de interferir em outros processos cognitivos e que o conhecimento atua na tomada de decisões, investigamos a relação entre o nível de conhecimento sobre o sono e os hábitos e a qualidade de sono, e os componentes da atenção de jovens de uma universidade pública do RN.
Ver mais..

Relação entre exposição à luz em sala de aula, ciclo sono-vigília e atenção em adolescentes de diferentes cidades do RN
Abstract: Em adolescentes, o atraso de fase do sono está associado à redução na duração do sono, ocasionando aumento na sonolência diurna e baixo desempenho acadêmico. O baixo desempenho pode estar relacionado à redução na atenção, processo cognitivo, cujos componentes apresentam variação circadiana, e assim como o ciclo sono-vigília (CSV) pode ser modulado por ciclos de luz-escuro. Portanto, este estudo tem como objetivo verificar a existência de relações entre a intensidade luminosa na sala de aula e o CSV, qualidade de sono, sonolência diurna e atenção em adolescentes do turno matutino de escolas privadas da capital (C) (Natal: Latitude: 05º 47′ 42″ Sul, Longitude: 35º 12′ 34″ Oeste) e do interior (I) (Santa Cruz: Latitude: 6° 13′ 46” Sul, Longitude: 36° 1′ 24” Oeste) do estado do RN. Participaram do estudo 115 adolescentes (C: 56 e I: 59), de ambos os sexos (41 meninos), matriculados no 1º e 2º anos do ensino médio.
Ver mais..

Rhythmic changes in Fabry disease: Inversion and non-oscillatory pattern in 6-sulfatoxymelatonin daily profile
Abstract: Fabry disease is a progressive disease characterized by an enzymatic deficiency of acid alpha-galactosidase and glycosphingolipids storage within the lysosomes. The disease has two phenotypes: classic and nonclassic. Excessive daytime sleepiness is a common sign reported by patients and can be caused by a circadian rhythm sleep disorder. Activity and rest cycle, variation of body temperature and melatonin biosynthesis are known rhythmicity markers. In the face of these evidences, our goal was to evaluate the rhythmic profile in Fabry’s disease patients using rhythmicity markers. 

Ver mais..
Sleep and light exposure across different levels of urbanisation in Brazilian communities

Abstract: Quilombos are settlements originally founded by Africans and African descendants (Quilombolas) in remote parts of Brazil to escape slavery. Due to individual histories, Quilombos nowadays exhibit different states of industrialisation, making them ideal for studying the influence of electrification on daily behaviour. In a comparative approach, we aimed to understand whether and how human sleep changes with the introduction of artificial light. We investigated daily rest-activity-rhythms and sleep-patterns in the Quilombolas’ by both wrist actimetry and the Munich ChronoType Questionnaire (MCTQ; the results of these two instruments correlated highly). 

Ver mais..

SleepData – Sleep Disorders Clinical Platform
Abstract: Esta dissertação apresenta o design e desenvolvimento do SleepData, uma nova plataforma de informação para a gestão de dados clínicos de distúrbios do sono. A plataforma integra dados de múltiplas fontes produzidas por uma diversidade de dispositivos de monitorização e testes laboratoriais. O SleepData fornece ferramentas para análise estatística e ferramentas de suporte ao diagnóstico, especialmente concebidas para estudar pacientes com síndrome do atraso das fases do sono (SAFS) e insónia.
Ver mais..

Social jetlag impairs balance control

Abstract: We assessed the impact of a common sleep disturbance, the social jetlag, on postural control during a period involving workdays and free days. The sleep habits of 30 healthy subjects were registered with a wrist actimeter for nine days (starting on Friday) and they participated in a set of four postural control tests carried out on Friday and on Monday. In addition, the subjects filled questionnaires about their sleep conditions and preferences. Actimetry measurements were used to calculate the Mid Sleep Phase (MSP). The difference between the MSP values on the workdays and free days measures the social jetlag. There were significant differences in sleep variables between workdays and free days. Postural control performance improved on Monday, after free sleep over the weekend, when compared with the tests performed on Friday. It seems that social jetlag affects brain areas involved in the control of posture, such as thalamus and the prefrontal cortex as well as the cerebellum, resulting in a worse performance in postural control. The performance improvement in the posture tests after the free days could be attributed to a lower sleep debt.

Ver mais..

The Psychological and Physiological Part of Emotions: Multimodal Approximation for Valence Classification
Abstract: In order to develop more precise and functional affective applications, it is necessary to achieve a balance between the psychology and the engineering applied to emotions. Signals from the central and peripheral nervous systems have been used for emotion recognition purposes, however, their operation and the relationship between them remains unknown. In this context, in the present work we have tried to approach the study of the psychobiology of both systems in order to generate a computational model for the recognition of emotions in the dimension of valence. To this end, the electroencephalography (EEG) signal, electrocardiography (ECG) signal and skin temperature of 24 subjects have been studied.
Ver mais..

The Use of Actigraphy for Risk Stratification in Pediatric Obstructive Sleep Apnea
Abstract: Sleep disordered breathing (SDB) in children is a spectrum of abnormal breathing patterns, characterized by a limitation of airflow during sleep. Upper airway resistance and collapse of the pharynx can cause varying degrees of obstruction, which can be exacerbated by the presence of adenotonsillar hypertrophy, obesity, and craniofacial or neuromuscular disorders. The spectrum of SDB ranges from primary snoring (PS), to upper airway resistance syndrome (UARS), to the most severe diagnosis of obstructive sleep apnea (OSA).1 Obstructive sleep apnea can be further stratified into mild, moderate, and severe categories. This spectrum is based on the frequency and severity of airflow obstructions, arousals, and gas exchange abnormalities during sleep.

Ver mais..

Validação de um actígrafo nacional
Abstract: O actígrafo consiste em um aparelho de pulso equipado com um acelerômetro, um microprocessador e uma memória interna, que são capazes de detectar e armazenar o registro de movimentos. A actigrafia é utilizada na avaliação de transtornos do sono como doenças de ritmo circadiano, insônia e sonolência excessiva diurna. Este método apresenta algumas vantagens em relação à polissonografia como o período de avaliação maior, simplicidade no uso e na interpretação e baixo custo. Este estudo tem por objetivo validar o actígrafo ActTrust na avaliação de sono e vigília comparando-o com a polissonografia. 

Ver mais..