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Asian Journal of Andrology ; (6): 184-191, 2023.
Article in English | WPRIM | ID: wpr-971016


The circadian clock is an evolutionary molecular product that is associated with better adaptation to changes in the external environment. Disruption of the circadian rhythm plays a critical role in tumorigenesis of many kinds of cancers, including prostate cancer (PCa). Integrating circadian rhythm into PCa research not only brings a closer understanding of the mechanisms of PCa but also provides new and effective options for the precise treatment of patients with PCa. This review begins with patterns of the circadian clock, highlights the role of the disruption of circadian rhythms in PCa at the epidemiological and molecular levels, and discusses possible new approaches to PCa therapy that target the circadian clock.

Humans , Male , Carcinogenesis , Circadian Clocks/physiology , Circadian Rhythm/physiology , Prostatic Neoplasms/physiopathology
Rev. Nutr. (Online) ; 35: e220037, 2022. tab, graf
Article in English | LILACS | ID: biblio-1406917


ABSTRACT Objective This study aimed to evaluate the perception and sensory acceptance of sweet taste by individuals who work/study on different shifts. Methods Three groups of individuals were recruited: the Control group (individuals that study during the day and do not work at night), Group 1 (individuals that study in the evening) and Group 2 (individuals that work overnight). The individuals were submitted to a detection threshold test using sucrose solutions and a sensory acceptance test using a structured hedonic scale and a Just-About-Right scale for sweet taste in blancmange. Results The detection thresholds were significantly higher for Groups 1 and 2. Individuals of Group 2 had a preference by blancmanges when having high sucrose concentrations, as well as had an ideal concentration of 10.50% sucrose against 5.95% sucrose for the Control group. Conclusion Our study shows a relationship between changes in the circadian cycle and the sensory perception and acceptance of sweet taste. More studies need to be performed to understand such relationships and their repercussions better.

RESUMO Objetivo O objetivo deste estudo foi avaliar a percepção e a aceitação sensorial do gosto doce por indivíduos que trabalham/estudam em diferentes turnos. Métodos Foram recrutados três grupos de indivíduos: Grupo Controle (indivíduos que estudam durante o dia e não trabalham à noite), Grupo 1 (indivíduos que estudam à noite) e Grupo 2 (indivíduos que trabalham de madrugada). Os indivíduos foram submetidos ao teste de limiar de detecção utilizando soluções de sacarose e aos testes de aceitação sensorial utilizando escala hedônica estruturada e escala do ideal para o gosto doce em manjar branco. Resultados Os limiares de detecção foram significativamente maiores para os Grupos 1 e 2, sendo certo que os indivíduos do Grupo 2 tiveram preferência pelos manjares com altas concentrações de sacarose, assim como apresentaram uma concentração ideal de 10,50% de sacarose contra 5,95% de sacarose para o grupo Controle. Conclusão Este estudo mostra uma relação entre mudanças no ciclo circadiano e a percepção e a aceitação sensorial do gosto doce, mostrando que estudos mais aprofundados precisam ser realizados para entender melhor tais relações e suas repercussões.

Humans , Male , Female , Adult , Young Adult , Sensory Thresholds/physiology , Sucrose/metabolism , Taste Perception/physiology , Circadian Rhythm/physiology
Journal of Biomedical Engineering ; (6): 248-256, 2022.
Article in Chinese | WPRIM | ID: wpr-928220


Difference of chronotypes makes influence to cognitive performance of individuals in routine duties. In this paper, 55 subjects with different chronotypes were subjected to continuous sleep deprivation for 30 h by using the constant routine protocol, during which core body temperature was measured continuously, and subjective sleepiness self-rating and the performance of selective attention were measured hourly. The results showed that the phase difference of core body temperature has no significant difference, yet the amplitude and term difference among the three chronotypes are significant. There was an advance in phase between subjective sleepiness self-rating and core body temperature, and the self-rating sleepiness of evening type came the latest, and the self-rating sleepiness of morning type dissipated the fastest. The response time of selective attention showed a 2 h phase delay with subjective sleepiness self-rating. And the analysis of core body temperature showed that the later the chronotype was, the greater the phase delay was. The correct rate of selective attention of different chronotypes were inconsistent with delay of subjective sleepiness self-rating and core body temperature. We provide reference for industry, aviation, military, medical and other fields to make a more scientific scheduling/ shifting based on cognitive performance characteristics of different chronotypes.

Humans , Attention/physiology , Circadian Rhythm/physiology , Homeostasis , Sleep/physiology , Sleep Deprivation , Sleepiness
Acta Physiologica Sinica ; (6): 443-460, 2022.
Article in Chinese | WPRIM | ID: wpr-939579


The mammalian internal circadian clock system has been evolved to adapt to the diurnal changes in the internal and external environment of the organism to regulate diverse physiological functions, such as the sleep-wake cycle and feeding rhythm, thereby coordinating the rhythmic changes of energy demand and nutrition supply in each diurnal cycle. The circadian clock regulates glucose metabolism, lipid metabolism, and hormones secretion in diverse tissues and organs, including the liver, skeletal muscle, pancreas, heart, and vessels. As a special "organ" of the host, the gut microbiota, together with the intestinal microenvironment (tissues, cells, and metabolites) in a co-evolutionary process, constitutes a micro-ecosystem and plays an important role in the process of nutrient digestion and absorption in the intestine of the host. In recent years, accumulating evidence indicates that the compositions, quantities, colonization, and functional activities of the gut microbiota exhibit significant circadian variations, which are closely related to the changes of various physiological functions under the regulation of host circadian clock system. In addition, several studies have shown that the gut microbiota can produce many important metabolites such as the short-chain fatty acids through the degradation of indigestive dietary fibers. A portion of gut microbiota-derived metabolites can regulate the circadian clock system and metabolism of the host. This article mainly discusses the interaction between the host circadian clock system and the gut microbiota, and highlights its influence on energy metabolism of the host, providing a novel clues and thought for the prevention and treatment of metabolic diseases.

Animals , Circadian Clocks/physiology , Circadian Rhythm/physiology , Ecosystem , Energy Metabolism , Gastrointestinal Microbiome/physiology , Lipid Metabolism/physiology , Mammals
Journal of Central South University(Medical Sciences) ; (12): 1740-1747, 2022.
Article in English | WPRIM | ID: wpr-971359


The psychological distress of cancer patients seriously affects their therapeutic effects. Effective psychological rehabilitation of cancer patients significantly improves their survival chance and quality of life. Circadian rhythm results from adaptation to the environment during the organism's evolution. When the endogenous clock system is disrupted or the external environment is changed, the body and the environment are out of synchronization, and the circadian rhythm will be disrupted. Circadian rhythm disorder is a common phenomenon in cancer patients, and the changes of circadian rhythm are closely related to their psychological distress. Many studies believe that the circadian rhythm disorder of cancer patients may directly or indirectly affect their psychology through various mechanisms, and targeted intervention by regulating the circadian rhythm of patients may be an essential means to promote the psychological rehabilitation.

Humans , Quality of Life , Circadian Rhythm/physiology , Chronobiology Disorders , Neoplasms
Chinese Journal of Stomatology ; (12): 481-489, 2022.
Article in Chinese | WPRIM | ID: wpr-935890


Circadian rhythm is an internal autonomous timing mechanism formed by the body in response to changes of external environment. It participates in the regulations of various physiological activities, affecting the formation and outcome of various diseases in the human body. This paper summarizes the changes of local tissue rhythms in common disease states, such as oral and maxillofacial malformations, inflammation and malignant tumors. The importance of circadian clock system to the activities of oral and maxillofacial tissues are dialectically analyzed, mainly on the mechanisms of action in maintaining oral health and in affecting the processes of common oral diseases and oral-related systemic diseases. At the same time, chronological therapy and new strategies of prevention and treatment for oral-related diseases based on the changes in tissue rhythm are summarized and prospected to provide new ideas for maintaining oral and systemic health.

Humans , Circadian Clocks/physiology , Circadian Rhythm/physiology , Inflammation , Mouth Diseases , Neoplasms
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 42(3): 258-263, May-June 2020. tab, graf
Article in English | LILACS | ID: biblio-1132073


Objective: Sleep, physical activity, and social domains of biological rhythm disruptions may have specific effects on the symptom cluster and severity of depression. However, there is a lack of structured clinical evaluation to specify the domains of biological rhythms in patients with depression. Methods: Ninety drug-naïve subjects with depression and 91 matched healthy controls were recruited for the study. The severity of depression was examined with the Hamilton Rating Scale for Depression (HRSD), while biological rhythm was evaluated using the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN). Results: Patients with depression showed significantly greater biological rhythm disturbances than healthy controls in all domains of BRIAN (sleep, activity, social, and eating). BRIAN-Total correlated positively with HRSD-Total and HRSD-Total without sleep cluster. The sleep and activity domains correlated significantly with HRSD-Total score. Additionally, the sleep, activity, and social domains correlated significantly with HRSD-Total without the sleep cluster score. Regression analysis revealed the activity (β = 0.476, t = 5.07, p<0.001) and sleep (β = 0.209, t = 2.056, p = 0.043) domains may predict HRSD-Total score. Conclusion: Consideration of biological rhythm domains in clinical examination and focusing on the sleep and activity domains may hold promise for the management of depression.

Humans , Male , Female , Adolescent , Adult , Aged , Young Adult , Circadian Rhythm/physiology , Depressive Disorder, Major/psychology , Psychiatric Status Rating Scales , Reference Values , Sleep/physiology , Time Factors , Exercise/psychology , Case-Control Studies , Cross-Sectional Studies , Regression Analysis , Depressive Disorder, Major/therapy , Exercise Therapy , Middle Aged
Rev. bras. neurol ; 56(1): 11-18, jan.-mar. 2020. ilus, graf, tab
Article in English | LILACS | ID: biblio-1095930


The sleep-wake cycle that is circadian rhythm may have different patterns according to sex, environment and genetics determinants. This chronological cycle type, chronotype, may be populational expressed by the extremes, early or later going to bed and waking up, in a continuum. The first, the Morning-type individuals (the lark) and the later, the Evening types (the owl). Between the two extremes, there is the majority of these chronotypes ­ the intermediate ones. These patterns may be classified according to the questionnaires such as Horne and Ostberg Morningness/ Eveningness Questionnaire (MEQ) and the Munich Chrono Type Questionnaire (MCTQ). The rural population tends to be Morning-type, as well as children and younger women, more than men. The Morning person tends to be more healthy than the Evening ones who are more prone to diseases, as depression and metabolic syndrome. This basic knowledge may be helpful to patient's counseling and management: to avoid mismatch of circadian physiology and social duties / sleep. This circadian desynchrony can increase the risk of diseases, consequently there is a need to chrono-medicine into current treatment strategies.

O ciclo sono-vigília, que é um ritmo circadiano, pode ter padrões diferentes de acordo com os determinantes sexuais, ambientais e genéticos. Esse tipo de ciclo cronológico, cronótipo, pode ser expresso em termos populacionais pelos extremos, indo cedo ou mais tarde para a cama ou saindo dela, em um continuum. O primeiro, os indivíduos do tipo Manhã (a cotovia) e o posterior, os tipos da Tarde (a coruja). Entre os dois extremos, há a maioria desses cronotipos - os intermediários. Esses padrões podem ser classificados de acordo com questionários como o Horne e Ostberg Morningness/Eveningness Questionnaire (MEQ) e o Munich Chrono Type Questionnaire (MCTQ). A população rural tende a ser do tipo matutino, assim como crianças e mulheres mais jovens, mais que os homens.A pessoa da manhã tende a ser mais saudável do que as da noite, mais propensa a doenças, como depressão e síndrome metabólica. Esse conhecimento básico pode ser útil para o aconselhamento e tratamento dos pacientes: para evitar incompatibilidade entre a fisiologia circadiana e os deveres sociais / sono. Essa dessincronia circadiana pode aumentar o risco de doenças, consequentemente, é necessário a cronomedicina nas atuais estratégias de tratamento.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Sleep/physiology , Biological Clocks , Circadian Rhythm/physiology , Sleep Stages , Sex Factors , Surveys and Questionnaires , Actigraphy , Circadian Clocks/physiology
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 42(1): 68-71, Jan.-Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1055368


Objective: Circadian dysregulation plays an important role in the etiology of mood disorders. Evening chronotype is frequent in these patients. However, prospective studies about the influence of chronotype on mood symptoms have reached unclear conclusions in patients with bipolar disorder (BD). The objective of this study was to investigate relationship between chronotype and prognostic factors for BD. Methods: At the baseline, 80 euthymic BD patients answered a demographic questionnaire and clinical scales to evaluate anxiety, functioning and chronotype. Circadian preference was measured using the Morningness-Eveningness Questionnaire, in which lower scores indicate eveningness. Mood episodes and hospitalizations were evaluated monthly for 18 months. Results: Among the BD patients, 14 (17.5%) were definitely morning type, 35 (43.8%), moderately morning, 27 (33.7%) intermediate (neither) and 4 (5%) moderately evening. Eveningness was associated with obesity or overweight (p = 0.03), greater anxiety (p = 0.002) and better functioning (p = 0.01), as well as with mood episodes (p = 0.04), but not with psychiatric hospitalizations (p = 0.82). This group tended toward depressive episodes (p = 0.06), but not (hypo)mania (p = 0.56). Conclusion: This study indicated that evening chronotype predicts a poor prognostic for BD. It reinforces the relevance of treating rhythm disruptions even during euthymia to improve patient quality of life and prevent mood episodes.

Humans , Male , Female , Adult , Aged , Young Adult , Anxiety/physiopathology , Bipolar Disorder/physiopathology , Circadian Rhythm/physiology , Prognosis , Psychiatric Status Rating Scales , Quality of Life , Time Factors , Logistic Models , Prospective Studies , Surveys and Questionnaires , Statistics, Nonparametric , Chronobiology Disorders/physiopathology , Hospitalization/statistics & numerical data , Middle Aged
Medicina (B.Aires) ; 79(supl.3): 29-32, set. 2019.
Article in Spanish | LILACS | ID: biblio-1040546


Las investigaciones recientes demuestran que mientras estamos tranquilamente durmiendo nuestro cerebro está muy ocupado procesando la información obtenida a lo largo del día. Asimismo, la falta de sueño ocasiona problemas en la consolidación de la memoria. El sueño juega un papel fundamental en el adecuado desarrollo del cerebro en crecimiento y muchos de los fenómenos de plasticidad cerebral ocurren durante el sueño. A nivel celular, los ciclos circadianos coordinan complejos mecanismos de "encender y apagar" genes y estructuras que regulan individualmente y colectivamente las funciones de cada célula del organismo y a su vez de cada órgano, cada sistema fisiológico, para finalmente producir un perfecto equilibrio en el funcionamiento mental, emocional y sistémico del individuo. El sueño influye en los procesos de memoria, aprendizaje, estados de ánimo y comportamiento, en las respuestas inmunológicas, procesos metabólicos, niveles de hormonas, digestión y muchas más funciones fisiológicas. Aquí presentamos una breve revisión de tres aspectos fundamentales relacionados con el sueño, enfocado especialmente en el efecto que tienen en procesos de aprendizaje y memoria: a. actividad eléctrica cerebral durante el sueño y correlación neuroanatómica con los mecanismos fisiológicos de memoria y aprendizaje; b. ciclos circadianos y su importancia en el funcionamiento de diferentes sistemas fisiológicos; c. algunos ejemplos de trastornos clínicos asociados con trastornos del sueño y sus repercusiones en aprendizaje y memoria.

Recent studies have demonstrated that while we are sleeping, our brain is very busy processing all information we have acquired along the day. Lack of sleep has shown to produce deficits in memory consolidation and plays an important role in brain development and brain plasticity in the several developmental stages of the human brain. At the cellular level, circadian cycles coordinate complex mechanism that "turn on and off" genes and cellular structures regulating individual cell functions to impact global organ and systems physiological activities. At the end a perfect and coordinated equilibrium in the mental, emotional and physiological is the goal of this complex process. Sleep impacts memory, learning, mood, behavior, immunological responses, metabolism, hormone levels, digestive process and many more physiological functions. We present a review of three basic aspects related with sleep: a. brain electrical activity during the sleep and neuroanatomic correlation with mechanism related with memory and learning; b. circadian cycles and impact in several physiological systems; c some examples of clinical disorders associated with sleep disorders and impact in learning and memory.

Humans , Sleep/physiology , Circadian Rhythm/physiology , Learning/physiology , Memory/physiology , Neuronal Plasticity/physiology , Sleep Wake Disorders/physiopathology , Brain/physiology , Emotions/physiology
Medicina (B.Aires) ; 79(1,supl.1): 44-50, abr. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1002604


El sueño adecuado es necesario para el desarrollo sináptico y la maduración cerebral, un sueño de mala calidad tiene efectos perjudiciales en las funciones cognitivas, de atención, memoria y conducta de los niños. La preocupación sobre la alta prevalencia de los problemas del sueño es amplia en todo el mundo; las consecuencias de estos problemas son incluso más importantes en los niños portadores de trastornos del neurodesarrollo; estos niños a menudo tienen dificultades de inicio y mantenimiento del sueño y despertares nocturnos frecuentes que afectan a sus problemas de conducta. El propósito de este escrito es revisar el estado del arte de los problemas del sueño en los niños con trastornos del neurodesarrollo. En este punto, es importante tener en cuenta el ritmo circadiano, un reloj que genéticamente dirige los ritmos celulares de transcripción, traslación y metabolismos. Este reloj se combina con el ambiente diurno y nocturno coordinando estos mecanismos durante los ciclos luz/oscuridad, sueño/vigilia, frío/calor, ingesta/ayuno, tanto diariamente como en las diferentes estaciones. En conclusión, los problemas del sueño son un factor condicionante de la evolución y calidad de vida de los niños con trastornos del neurodesarrollo, que debe ser tenido en cuenta en todos los casos y ocupar un lugar preferente tanto en la etapa diagnóstica como en la terapéutica.

Adequate sleep is of critical need for a typical synaptic development and brain maturation, a poor quality sleep can have detrimental effects on children's' cognitive attention, memory, mood regulation, and behavior functions. Great concern has been voiced out regarding the high prevalence of poor sleep in children worldwide, the effects of poor sleep may be even more pronounced in children with neurodevelopmental disorders; these children often have difficulties with falling and staying asleep and with night awakenings, this has a strong association with daytime behavior problems. The purpose of this article is to provide an overview of the state of the science of sleep in children with a neurodevelopmental disorder. In this context, it is important to take the circadian cycle into account, a genetically encoded clock that drives cellular rhythms of transcription, translation and metabolism. The circadian clock interacts with the diurnal and nocturnal environment that also drives transcription and metabolism during light/dark, sleep/wake, hot/cold and feast/fast daily and seasonal cycles In conclusion, the sleep problems are a conditioning factor in the evolution and quality of life of children with neurodevelopmental disorders that must be taken into account in all cases and occupy a preferential place in both the diagnostic and the therapeutic stages.

Humans , Child , Sleep Wake Disorders/physiopathology , Neurodevelopmental Disorders/physiopathology , Attention Deficit Disorder with Hyperactivity/physiopathology , Sleep Wake Disorders/therapy , Circadian Rhythm/physiology , Smith-Magenis Syndrome/physiopathology , Circadian Clocks , Autism Spectrum Disorder/physiopathology , Sleep Hygiene/physiology
Braz. j. biol ; 78(4): 763-772, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951606


Abstract Most studies on mechanisms regulating fish larvae processes have focused on assessing the isolated effects of food distribution and feeding behavior. However, in natural ecosystems, fish larvae may strongly interact with zooplankton organisms in an array of complex, direct and indirect interdependencies. This study analyzed the spatial distribution, diet and feeding behavior of early stages of Hypophthalmus edentatus and Plagioscion squamosissimus, two fish species co-occurring in an isolated floodplain lake, during the light-dark cycle. Larvae fed more actively during dark periods (dusk and night) when they migrated toward the surface of the lake, and remained on the bottom and fed less during light periods (day and dawn). Cladocerans represented the most frequent prey in the diet of H. edentatus larvae. In turn, P. squamosissimus larvae initially preferred cladocerans and, as they developed, included calanoid copepods in the diet. Significant differences were detected in the frequencies of food items consumed during larval development, which could be related to a better ability of the most developed stages to explore the environment in search of other prey.

Resumo A maioria dos estudos de mecanismos que regulam os processos de larvas de peixes se concentra na avaliação dos efeitos isolados da distribuição do alimento e do comportamento alimentar. No entanto, em ecossistemas naturais, as larvas de peixes podem interagir fortemente com os organismos do zooplâncton em uma série de interdependências complexas, diretas e indiretas. Este estudo analisou a distribuição espacial, dieta e comportamento alimentar dos estágios iniciais de vida de Hypophthalmus edentatus e Plagioscion squamosissimus, duas espécies de peixes coexistentes em uma lagoa isolada de planície de inundação, durante o ciclo claro-escuro. As larvas se alimentaram mais ativamente durante os períodos escuros (crepúsculo e noite) quando ascenderam em direção à superfície da lagoa, enquanto durante os períodos luminosos (dia e amanhecer) permaneceram no fundo e pouco se alimentaram. Os cladóceros foram as presas mais frequentes na dieta de larvas de H. edentatus. Por sua vez, larvas de P. squamosissimus inicialmente preferiram cladóceros, e a medida que se desenvolveram incluíram copépodes calanóides na dieta. Diferenças significativas foram detectadas nas frequências dos itens alimentares consumidos durante o desenvolvimento larval, o que poderia estar relacionado a uma melhor capacidade dos estágios mais desenvolvidos em explorar o ambiente na busca por outras presas.

Animals , Circadian Rhythm/physiology , Feeding Behavior/physiology , Fishes/physiology , Larva/physiology , Brazil , Lakes , Population Density , Photoperiod , Ecosystem , Diet
Braz. j. biol ; 78(4): 697-705, Nov. 2018. tab, graf
Article in English | LILACS | ID: biblio-951600


Abstract Between July 2014 and April 2015, we conducted weekly inventories of the circadian activity patterns of mammals in Passo Novo locality, municipality of Alegrete, southern Brazil. The vegetation is comprised by a grassy-woody steppe (grassland). We used two camera traps alternately located on one of four 1 km transects, each separated by 1 km. We classified the activity pattern of species by the percentage of photographic records taken in each daily period. We identify Cuniculus paca individuals by differences in the patterns of flank spots. We then estimate the density 1) considering the area of riparian forest present in the sampling area, and 2) through capture/recapture analysis. Cuniculus paca, Conepatus chinga and Hydrochoerus hydrochaeris were nocturnal, Cerdocyon thous had a crepuscular/nocturnal pattern, while Mazama gouazoubira was cathemeral. The patterns of circadian activity observed for medium and large mammals in this Pampa region (southern grasslands) may reflect not only evolutionary, biological and ecological affects, but also human impacts not assessed in this study. We identified ten individuals of C. paca through skin spot patterns during the study period, which were recorded in different transects and months. The minimum population density of C. paca was 3.5 individuals per km2 (resident animals only) and the total density estimates varied from 7.1 to 11.8 individuals per km2, when considering all individuals recorded or the result of the capture/recapture analysis, respectively.

Resumo De julho de 2014 a abril de 2015, realizamos levantamentos semanais para estudar padrões de atividade circadiana da mastofauna na localidade de Passo Novo, Alegrete, sul do Brasil. A vegetação é compreendida por savana estépica (campo). Utilizamos duas armadilhas fotográficas distribuídas alternadamente ao longo de quatro transectos, com extensão de 1 km e distantes cerca de 1 km entre si. Nós classificamos o padrão de atividade das espécies através da percentagem de fotos registradas em cada período diário. Nós identificamos indivíduos de Cuniculus paca através dos diferentes padrões de manchas nos flancos dos animais. Nós então estimamos a densidade 1) considerando a área de floresta ripária presente na área amostrada, e 2) através da análise de captura/recaptura. As espécies Cuniculus paca, Conepatus chinga e Hydrochoerus hydrochaeris foram classificadas como noturnas, Cerdocyon thous apresentou um padrão crepuscular/noturno, enquanto Mazama gouazoubira foi classificada como catemeral. O padrão de atividade circadiana observado para os mamíferos de médio e grande porte nessa região do Pampa (campos sulinos) pode refletir não só aspectos evolutivos, biológicos e ecológicos, mas também impactos humanos não avaliados nesse estudo. Através do padrão de manchas da pelagem de C. paca nós identificamos dez indivíduos durante o período de estudo, que foram registrados em diferentes transectos e meses. A densidade populacional mínima de C. paca foi de 3,5 ind/km2 (apenas indivíduos residentes) e a densidade total variou de 7,1 a 11,8 ind/km2, quando consideramos todos os indivíduos registrados ou com base em análises de captura e recaptura, respectivamente.

Animals , Circadian Rhythm/physiology , Mammals/physiology , Brazil , Forests , Population Density , Ecology , Biological Evolution
Arch. endocrinol. metab. (Online) ; 62(4): 472-479, July-Aug. 2018. graf
Article in English | LILACS | ID: biblio-950082


ABSTRACT Melatonin is a ubiquitous molecule in nature, being locally synthesized in several cells and tissues, besides being a hormone that is centrally produced in the pineal gland of vertebrates, particularly in mammals. Its pineal synthesis is timed by the suprachiasmatic nucleus, that is synchronized to the light-dark cycle via the retinohypothalamic tract, placing melatonin synthesis at night, provided its dark. This unique trait turns melatonin into an internal synchronizer that adequately times the organism's physiology to the daily and seasonal demands. Besides being amphiphilic, melatonin presents specific mechanisms and ways of action devoted to its role as a time-giving agent, being widely spread in the organism. The present review aims to focus on melatonin as a pineal hormone with specific mechanisms and ways of action, besides presenting the clinical syndromes related to its synthesis and/or function disruptions.

Humans , Melatonin/physiology , Sleep Wake Disorders/drug therapy , Circadian Rhythm/physiology , Melatonin/metabolism , Melatonin/therapeutic use
Medicentro (Villa Clara) ; 22(1): [74-76], ene.-mar. 2018.
Article in Spanish | LILACS | ID: biblio-946759


El ritmo biológico refleja la adaptación fisiológica a las fluctuaciones ambientales. Los seres humanos son por naturaleza activos durante el día y descansan por la noche; sin embargo, condicionado por la tipología circadiana o cronotipo de cada individuo, existe variabilidad en la hora preferida para dormir, en los niveles de alerta y la disposición para realizar actividades; con el fin de evaluar esta peculiaridad, se han desarrollado instrumentos, como el cuestionario de matutinidad y vespertinidad y el cuestionario del cronotipo de Múnich. Trabajar o estudiar en horarios desalineados al cronotipo individual implica riesgos para la salud, que se agravan cuando la situación se hace crónica; este tema de investigación, paradójicamente, permanece inexplorado en Cuba. Es criterio del autor que amerita desarrollar investigaciones al respecto, pues estas podrían sugerir intervenciones que impacten favorablemente en el estado de salud y rendimiento de los estudiantes universitarios.

Circadian Rhythm/physiology
Rev. bras. oftalmol ; 77(1): 14-19, jan.-fev. 2018. tab, graf
Article in Portuguese | LILACS | ID: biblio-899111


Resumo Objetivo: Avaliar a concordância entre os tonômetros de aplanação de Goldman e pneumático na realização do teste de sobrecarga hídrica (TSH). Métodos: Estudo descritivo transversal composto por uma amostra de 102 olhos proveniente de um hospital particular em Goiânia (GO) entre 2013 a 2016, com avaliação das diferentes pressões intraoculares (PIO) nos tonômetros de aplanação de Goldman e pneumático quando submetidos ao TSH. Resultados: A média de idade foi de 52,17 (± 15,21) anos, sendo que60,8% dos pacientes pertenciam ao sexo feminino e 39,2% ao masculino. A média da espessura da córnea foi de 531,9(± 72,75) micra. Por regressão linear as variaveis idade e espessura da cornea central não ocorreram significancia estatistica entre os dois dispositivos analisados. Conclusão: Observou-se boa concordância nas medições entre os aparelhos de aplanação e o pneumático durante o teste de sobrecarga hídrica, porém necessita-se de novos estudos de maior impacto epidemiológico para confirmação desta assertiva.

Abstract Objective: To evaluate the consonance betweenthe Goldman and pneumática planation to nometers under the effect of the water drink test. Methods: Cross-sectional descriptive study consisting of a sample of 102 eyes from a private hospital in Goiânia (GO) from 2013 to 2015,with na evaluation of different intraocular pressures (IOP) in the Goldman and pneumatic flattening to nometers when submitted to TSH. Results: The average age was 52.17 (± 15.21) years old, 60.8% of the patients were female and 39.2% were male.The mean corneal thickness was 531.9(± 72.75) By linear regression the variables age and corneal thickness did not occur statistical significance between the two devices analyzed. Conclusion: Good agreement was observed in the measurements between the applanation devices and the tire during the water drink test, but new studies with a greater epidemiological impact were required to confirm this assertion.

Humans , Male , Female , Middle Aged , Tonometry, Ocular/instrumentation , Tonometry, Ocular/methods , Drinking Water/administration & dosage , Glaucoma/diagnosis , Ocular Hypertension/diagnosis , Drinking/physiology , Intraocular Pressure/physiology , Time Factors , Cross-Sectional Studies , Reproducibility of Results , Hospitals, Private , Circadian Rhythm/physiology , Diagnostic Techniques, Ophthalmological , Electronic Health Records , Corneal Pachymetry , Sitting Position
Arq. bras. cardiol ; 109(4): 313-320, Oct. 2017. tab, graf
Article in English | LILACS | ID: biblio-887944


Abstract Background: Obesity, systemic arterial hypertension (SAH) and obstructive sleep apnea (OSA) are closely related. Up to 70% of patients with OSA may be asymptomatic, and there is evidence that these patients have cardiovascular disease, especially nocturnal SAH. Objectives: The aim of this study was to evaluate 24-hour blood pressure circadian variation in asymptomatic, obese individuals with moderate-to-severe OSA and compare it with that in individuals with mild OSA or without OSA. Methods: Eighty-six obese subjects aged between 30 and 55 years (BMI 30-39 kg/m2), with casual blood pressure < 140/90 mmHg and without comorbidities were recruited. Eighty-one patients underwent clinical and anthropometric assessment, ambulatory blood pressure monitoring (ABPM), and Watch-PAT. Participants were divided into two groups, based on the apnea-hypopnea index (AHI): group 1, with AHI < 15 events/hour, and group 2 with AHI ≥ 15 events/hour. Results: Compared with group 1, group 2 had higher neck circumference and waist-hip circumference (40.5 ± 3.2 cm vs. 38.0 ± 3.7 cm, p = 0.002, and 0.94 ± 0.05 vs. 0.89 ± 0.05, p = 0.001, respectively), higher systolic and diastolic blood pressure measured by the 24-h ABPM (122 ± 6 vs 118 ± 8 mmHg, p = 0.014, and 78 ± 6 vs 73 ± 7 mmHg, p = 0.008, respectively), and higher nocturnal diastolic pressure load (44,6 ± 25,9% vs 31,3 ± 27,3%, p = 0,041). Moreover, there was a positive correlation between nocturnal diastolic blood pressure and AHI (r = 0.43, p < 0.05). Conclusions: Asymptomatic obese subjects with moderate-to-severe OSA have higher systolic and diastolic blood pressure at 24 hours compared with those with absent / mild OSA, despite normal casual blood pressure between the groups. These results indicate that ABPM may be useful in the evaluation of asymptomatic obese patients with moderate-to-severe OSA.

Resumo Fundamentos: Obesidade, hipertensão arterial sistêmica (HAS) e apneia obstrutiva do sono (AOS) estão intimamente relacionados. Até 70% dos pacientes com AOS podem ser assintomáticos e há evidências que eles apresentam alterações cardiovasculares, em especial HAS noturna. Objetivos: O objetivo deste estudo foi avaliar o comportamento da pressão arterial nas 24 horas em indivíduos obesos assintomáticos com AOS moderada/grave comparando àqueles com AOS leve/ausente. Métodos: Foram selecionados 86 pacientes entre 30 e 55 anos, obesos (IMC 30-39,9 kg/m2), com pressão arterial casual < 140/90 mmHg e sem comorbidades, dos quais 81 foram submetidos à avaliação clínica, medidas antropométricas, monitorização ambulatorial da pressão arterial (MAPA) e Watch-PAT. Os participantes do estudo foram divididos em dois grupos com base no índice de apneia-hipopneia (IAH): grupo 1 com IAH < 15 eventos/h e grupo 2 com IAH ≥ 15 eventos/h. Resultados: Em comparação ao grupo 1, o grupo 2 apresentou maior circunferência de pescoço e maior relação cintura-quadril (40,5 ± 3,2 vs 38,0 ± 3,7 cm, p = 0,002, e 0,94 ± 0,05 vs 0,89±0,05cm, p = 0,001, respectivamente), maiores pressões arteriais sistólica e diastólica na MAPA-24h (122 ± 6 vs 117 ± 8 mmHg, p = 0,014, e 78 ± 6 vs 73 ± 7 mmHg, p = 0,008, respectivamente), bem como maior carga pressórica diastólica noturna (44,6 ± 25,9% vs 31,3 ± 27,3%, p = 0,041). Além disso, houve correlação positiva entre pressão arterial diastólica noturna e IAH (r = 0,43, p < 0,05). Conclusões: Indivíduos obesos assintomáticos com AOS de moderada a grave apresentam maiores valores de PA sistólica e diastólica nas 24 horas em comparação àqueles com AOS ausente/leve, apesar da PA casual normal. Esses resultados indicam que a MAPA pode ser útil na avaliação de pacientes obesos assintomáticos com AOS de moderada à grave.

Humans , Male , Female , Adult , Middle Aged , Blood Pressure/physiology , Sleep Apnea, Obstructive/physiopathology , Hypertension/physiopathology , Obesity/physiopathology , Reference Values , Time Factors , Severity of Illness Index , Anthropometry , Cross-Sectional Studies , Risk Factors , Circadian Rhythm/physiology , Statistics, Nonparametric , Blood Pressure Monitoring, Ambulatory/methods , Sleep Apnea, Obstructive/complications , Hypertension/etiology , Obesity/complications