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1.
Nat Commun ; 11(1): 1051, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103014

RESUMO

That attention is a fundamentally rhythmic process has recently received abundant empirical evidence. The essence of temporal attention, however, is to flexibly focus in time. Whether this function is constrained by an underlying rhythmic neural mechanism is unknown. In six interrelated experiments, we behaviourally quantify the sampling capacities of periodic temporal attention during auditory or visual perception. We reveal the presence of limited attentional capacities, with an optimal sampling rate of ~1.4 Hz in audition and ~0.7 Hz in vision. Investigating the motor contribution to temporal attention, we show that it scales with motor rhythmic precision, maximal at ~1.7 Hz. Critically, motor modulation is beneficial to auditory but detrimental to visual temporal attention. These results are captured by a computational model of coupled oscillators, that reveals the underlying structural constraints governing the temporal alignment between motor and attention fluctuations.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Periodicidade , Percepção Visual/fisiologia , Estimulação Acústica , Adolescente , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Fatores de Tempo , Adulto Jovem
2.
Nat Immunol ; 21(2): 168-177, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31873294

RESUMO

Group 3 innate lymphoid cell (ILC3)-mediated production of the cytokine interleukin-22 (IL-22) is critical for the maintenance of immune homeostasis in the gastrointestinal tract. Here, we find that the function of ILC3s is not constant across the day, but instead oscillates between active phases and resting phases. Coordinate responsiveness of ILC3s in the intestine depended on the food-induced expression of the neuropeptide vasoactive intestinal peptide (VIP). Intestinal ILC3s had high expression of the G protein-coupled receptor vasoactive intestinal peptide receptor 2 (VIPR2), and activation by VIP markedly enhanced the production of IL-22 and the barrier function of the epithelium. Conversely, deficiency in signaling through VIPR2 led to impaired production of IL-22 by ILC3s and increased susceptibility to inflammation-induced gut injury. Thus, intrinsic cellular rhythms acted in synergy with the cyclic patterns of food intake to drive the production of IL-22 and synchronize protection of the intestinal epithelium through a VIP-VIPR2 pathway in ILC3s.


Assuntos
Imunidade nas Mucosas/imunologia , Subpopulações de Linfócitos/imunologia , Linfócitos/imunologia , Periodicidade , Peptídeo Intestinal Vasoativo/imunologia , Animais , Ingestão de Alimentos/imunologia , Imunidade Inata/imunologia , Subpopulações de Linfócitos/metabolismo , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Peptídeo Intestinal Vasoativo/metabolismo
3.
Proc Natl Acad Sci U S A ; 117(2): 936-942, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31871195

RESUMO

Music and dance are universal across human culture and have an ancient history. One characteristic of music is its strong influence on movement. For example, an auditory beat induces rhythmic movement with positive emotions in humans from early developmental stages. In this study, we investigated if sound induced spontaneous rhythmic movement in chimpanzees. Three experiments showed that: 1) an auditory beat induced rhythmic swaying and other rhythmic movements, with larger responses from male chimpanzees than female chimpanzees; 2) random beat as well as regular beat induced rhythmic swaying and beat tempo affected movement periodicity in a chimpanzee in a bipedal posture; and 3) a chimpanzee showed close proximity to the sound source while hearing auditory stimuli. The finding that male chimpanzees showed a larger response to sound than female chimpanzees was consistent with previous literature about "rain dances" in the wild, where male chimpanzees engage in rhythmic displays when hearing the sound of rain starting. The fact that rhythmic swaying was induced regardless of beat regularity may be a critical difference from humans, and a further study should reveal the physiological properties of sound that induce rhythmic movements in chimpanzees. These results suggest some biological foundation for dancing existed in the common ancestor of humans and chimpanzees ∼6 million years ago. As such, this study supports the evolutionary origins of musicality.


Assuntos
Comportamento Animal/fisiologia , Dança/fisiologia , Movimento/fisiologia , Pan troglodytes/fisiologia , Som , Animais , Percepção Auditiva/fisiologia , Evolução Biológica , Dança/psicologia , Feminino , Humanos , Masculino , Música , Pan troglodytes/psicologia , Periodicidade , Postura , Fatores Sexuais
4.
Cochrane Database Syst Rev ; 12: CD008669, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31886897

RESUMO

BACKGROUND: Periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis (PFAPA) syndrome is a rare clinical syndrome of unknown cause usually identified in children. Tonsillectomy is considered a potential treatment option for this syndrome. This is an update of a Cochrane Review first published in 2010 and previously updated in 2014. OBJECTIVES: To assess the effectiveness and safety of tonsillectomy (with or without adenoidectomy) compared with non-surgical treatment in the management of children with PFAPA. SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane ENT Trials Register; Central Register of Controlled Trials (CENTRAL 2019, Issue 4); PubMed; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 15 October 2019. SELECTION CRITERIA: Randomised controlled trials comparing tonsillectomy (with or without adenoidectomy) with non-surgical treatment in children with PFAPA. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. The primary outcomes were the proportion of children whose symptoms have completely resolved and complications of surgery (haemorrhage and number of days of postoperative pain). Secondary outcomes were: number of episodes of fever and the associated symptoms; severity of episodes; use of corticosteroids; absence or time off school; quality of life. We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: Two trials were included with a total of 67 children randomised (65 analysed); we judged both to be at low risk of bias. One trial of 39 participants recruited children with PFAPA syndrome diagnosed according to rigid, standard criteria. The trial compared adenotonsillectomy to watchful waiting and followed up patients for 18 months. A smaller trial of 28 children applied less stringent criteria for diagnosing PFAPA and probably also included participants with alternative types of recurrent pharyngitis. This trial compared tonsillectomy alone to no treatment and followed up patients for six months. Combining the trial results suggests that patients with PFAPA likely experience less fever and less severe episodes after surgery compared to those receiving no surgery. The risk ratio (RR) for immediate resolution of symptoms after surgery that persisted until the end of follow-up was 4.38 (95% confidence interval (CI) 0.64 to 30.11); number needed to treat to benefit (NNTB) = 2, calculated based on an estimate that 156 in 1000 untreated children have a resolution) (moderate-certainty evidence). Both trials reported that there were no complications of surgery. However, the numbers of patients randomly allocated to surgery (19 and 14 patients respectively) were too small to detect potentially important complications such as haemorrhage. Surgery probably results in a large overall reduction in the average number of episodes over the total length of follow-up (rate ratio 0.08, 95% CI 0.05 to 0.13), reducing the average frequency of PFAPA episodes from one every two months to slightly less than one every two years (moderate-certainty evidence). Surgery also likely reduces severity, as indicated by the length of PFAPA symptoms during these episodes. One study reported that the average number of days per PFAPA episode was 1.7 days after receiving surgery, compared to 3.5 days in the control group (moderate-certainty evidence). The evidence suggests that the proportion of patients requiring corticosteroids was also lower in the surgery group compared to those receiving no surgery (RR 0.58, 95% CI 0.37 to 0.92) (low-certainty evidence). Other outcomes such as absence from school and quality of life were not measured or reported. AUTHORS' CONCLUSIONS: The evidence for the effectiveness of tonsillectomy in children with PFAPA syndrome is derived from two small randomised controlled trials. These trials reported significant beneficial effects of surgery compared to no surgery on immediate and complete symptom resolution (NNTB = 2) and a substantial reduction in the frequency and severity (length of episode) of any further symptoms experienced. However, the evidence is of moderate certainty (further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate) due to the relatively small sample sizes of the studies and some concerns about the applicability of the results. Therefore, the parents and carers of children with PFAPA syndrome must weigh the risks and consequences of surgery against the alternative of using medications. It is well established that children with PFAPA syndrome recover spontaneously and medication can be administered to try and reduce the severity of individual episodes. It is uncertain whether adenoidectomy combined with tonsillectomy adds any additional benefit to tonsillectomy alone.


Assuntos
Linfadenite/cirurgia , Faringite/cirurgia , Estomatite Aftosa/cirurgia , Tonsilectomia/métodos , Adenoidectomia/métodos , Criança , Pré-Escolar , Febre/cirurgia , Humanos , Lactente , Periodicidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Síndrome
5.
NeuroRehabilitation ; 45(4): 483-492, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31868694

RESUMO

BACKGROUND: Persons with stroke commonly have residual neurological deficits that seriously hamper mobility. OBJECTIVE: To investigate whether horse-riding therapy (H-RT) and rhythm and music-based therapy (R-MT) affect functional mobility in late phase after stroke. METHODS: This study is part of a randomized controlled trial in which H-RT and R-MT was provided twice weekly for 12 weeks. Assessment included the timed 10-meter walk test (10 mWT), the six-minute walk test (6 MWT) and Modified Motor Assessment Scale (M-MAS). RESULTS: 123 participants were assigned to H-RT (n = 41), R-MT (n = 41), or control (n = 41). Post-intervention, the H-RT group completed the 10 mWT faster at both self-selected (-2.22 seconds [95% CI, -3.55 to -0.88]; p = 0.001) and fast speed (-1.19 seconds [95% CI, -2.18 to -0.18]; p = 0.003), with fewer steps (-2.17 [95% CI, -3.30 to -1.04]; p = 0.002 and -1.40 [95% CI, -2.36 to -0.44]; p = 0.020, respectively), as compared to controls. The H-RT group also showed improvements in functional task performance as measured by M-MAS UAS (1.13 [95% CI, 0.74 to 1.52]; p = 0.001). The gains were partly maintained at 6 months among H-RT participants. The R-MT did not produce any immediate gains. However, 6 months post-intervention, the R-MT group performed better with respect to time; -0.75 seconds [95% CI, -1.36 to -0.14]; p = 0.035) and number of steps -0.76 [95% CI, -1.46 to -0.05]; p = 0.015) in the 10 mWT at self-selected speed. CONCLUSIONS: The present study supports the efficacy of H-RT in producing immediate gains in gait and functional task performance in the late phase after stroke, whereas the effectiveness of R-MT is less clear.


Assuntos
Terapia Assistida por Cavalos/métodos , Musicoterapia/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Animais , Feminino , Marcha , Humanos , Masculino , Pessoa de Meia-Idade , Periodicidade , Amplitude de Movimento Articular , Análise e Desempenho de Tarefas
6.
PLoS Comput Biol ; 15(10): e1007371, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31671096

RESUMO

Dancing and playing music require people to coordinate actions with auditory rhythms. In laboratory perception-action coordination tasks, people are asked to synchronize taps with a metronome. When synchronizing with a metronome, people tend to anticipate stimulus onsets, tapping slightly before the stimulus. The anticipation tendency increases with longer stimulus periods of up to 3500ms, but is less pronounced in trained individuals like musicians compared to non-musicians. Furthermore, external factors influence the timing of tapping. These factors include the presence of auditory feedback from one's own taps, the presence of a partner performing coordinated joint tapping, and transmission latencies (TLs) between coordinating partners. Phenomena like the anticipation tendency can be explained by delay-coupled systems, which may be inherent to the sensorimotor system during perception-action coordination. Here we tested whether a dynamical systems model based on this hypothesis reproduces observed patterns of human synchronization. We simulated behavior with a model consisting of an oscillator receiving its own delayed activity as input. Three simulation experiments were conducted using previously-published behavioral data from 1) simple tapping, 2) two-person alternating beat-tapping, and 3) two-person alternating rhythm-clapping in the presence of a range of constant auditory TLs. In Experiment 1, our model replicated the larger anticipation observed for longer stimulus intervals and adjusting the amplitude of the delayed feedback reproduced the difference between musicians and non-musicians. In Experiment 2, by connecting two models we replicated the smaller anticipation observed in human joint tapping with bi-directional auditory feedback compared to joint tapping without feedback. In Experiment 3, we varied TLs between two models alternately receiving signals from one another. Results showed reciprocal lags at points of alternation, consistent with behavioral patterns. Overall, our model explains various anticipatory behaviors, and has potential to inform theories of adaptive human synchronization.


Assuntos
Estimulação Acústica/métodos , Percepção Auditiva/fisiologia , Percepção do Tempo/fisiologia , Ciclos de Atividade , Antecipação Psicológica/fisiologia , Ciências Biocomportamentais , Simulação por Computador , Retroalimentação , Retroalimentação Sensorial/fisiologia , Humanos , Música , Periodicidade , Desempenho Psicomotor
7.
Strabismus ; 27(4): 205-210, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31746262

RESUMO

Purpose: Here we aimed to describe seven pediatric patients with cyclic strabismus and report the outcome of their surgical treatment.Methods: Seven children with acquired esotropia manifesting in a 48-h cycle were included in the study. Four of them were boys, and three of them were girls. All cases had a large angle of deviation and associated suppression on the esotropic day and small angle of deviation with fusion on the other day. A complete ocular motility examination was performed for seven consecutive days. For all cases, we planned strabismus surgery according to the amount of deviation on the strabismic day. Postoperatively, the deviation angles were recorded at the first week, first month, and third month. Later, the patients were examined at 3-month intervals.Results: The mean age at presentation was 4.42 ± 3.69 years (1-12 years). The mean angle of esotropia at near fixation preoperatively was 36.4 ± 14.9 pd (prism dioptre) (20-60 pd) on the esotropic day. The mean angle of esotropia on the esotropic day at distance fixation was 32.1 ± 6.9 pd (20-40 pd). The mean follow-up period was 18.4 ± 5.5 months (12-25 months). The mean duration of esotropia before surgery was 11.1 ± 9.4 months (3-29 months). Following surgery, orthophoria within 10 pd was achieved and maintained in all cases.Conclusion: When treating children with cyclic strabismus, the best surgical results can be achieved when surgery is planned according to the amount of deviation on the strabismic day.


Assuntos
Esotropia/cirurgia , Músculos Oculomotores/cirurgia , Procedimentos Cirúrgicos Oftalmológicos , Criança , Pré-Escolar , Percepção de Profundidade/fisiologia , Movimentos Oculares/fisiologia , Feminino , Fixação Ocular/fisiologia , Humanos , Lactente , Masculino , Periodicidade , Período Pós-Operatório , Estudos Retrospectivos
8.
PLoS Biol ; 17(10): e3000456, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31613884

RESUMO

Every year, billions of seasonal migrants connect continents by transporting nutrients, energy, and pathogens between distant communities and ecosystems. For animals that power their movements by endogenous energy stores, the daily energy intake rates strongly influence the speed of migration. If access to food resources varies cyclically over the season, migrants sensitive to changes in daily energy intake rates may adjust timing of migration accordingly. As an effect, individuals adjusting to a common temporal cycle are expected to approach synchrony in foraging and movement. A large-scale periodic pattern, such as the dark-light cycle of the moon, could thus synchronize migrations across animal populations. However, such cyclic effects on the temporal regulation of migration has not been considered. Here, we show the temporal influence of the lunar cycle on the movement activity and migration tactics in a visual hunting nocturnal insectivore and long-distance migrant, the European nightjar, Caprimulgus europeaus. We found that the daily foraging activity more than doubled during moonlit nights, likely driven by an increase in light-dependent fuelling opportunities. This resulted in a clear cyclicity also in the intensity of migratory movements, with occasionally up to 100% of the birds migrating simultaneously following periods of full moon. We conclude that cyclic influences on migrants can act as an important regulator of the progression of individuals and synchronize pulses of migratory populations, with possible downstream effects on associated communities and ecosystems.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Lua , Periodicidade , África , Animais , Ecossistema , Ingestão de Energia/fisiologia , Europa (Continente) , Feminino , Cadeia Alimentar , Insetos , Masculino , Fotoperíodo
9.
Neural Netw ; 119: 249-260, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31472291

RESUMO

This paper discusses the issue of periodicity and finite-time periodic synchronization of discontinuous complex-valued neural networks (CVNNs). Based on a modified version of Kakutani's fixed point theorem, general conditions are obtained to guarantee the periodicity of discontinuous CVNNs. Next, several criteria for finite-time periodic synchronization (FTPS) are given by using a new proposed finite-time convergence theorem. Different from the traditional convergence lemma, the estimated upper bound of the derivative of the Lyapunov function (LF) is allowed to be indefinite or even positive. In order to achieve FTPS, novel discontinuous control algorithms, including state-feedback control algorithm and generalized pinning control algorithm, are designed. In the generalized pinning control algorithm, a guideline is proposed to select neurons to pin the designed controller. Finally, two simulations are given to substantiate the main results.


Assuntos
Neurônios/fisiologia , Periodicidade , Algoritmos , Retroalimentação , Fatores de Tempo
10.
Biochim Biophys Acta Bioenerg ; 1860(11): 148073, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31473302

RESUMO

Photosystem I (PSI) is a potential target of photoinhibition under fluctuating light. However, photosynthetic regulation under fluctuating light in field-grown plants is little known. Furthermore, it is unclear how young leaves protect PSI against fluctuating light under natural field conditions. In the present study, we examined chlorophyll fluorescence, P700 redox state and the electrochromic shift signal in the young and mature leaves of field-grown Cerasus cerasoides (Rosaceae). Within the first seconds after any increase in light intensity, young leaves showed higher proton gradient (ΔpH) across the thylakoid membranes than the mature leaves, preventing over-reduction of PSI in the young leaves. As a result, PSI was more tolerant to fluctuating light in the young leaves than in the mature leaves. Interestingly, after transition from low to high light, the activity of cyclic electron flow (CEF) in young leaves increased first to a high level and then decreased to a stable value, while this rapid stimulation of CEF was not observed in the mature leaves. Furthermore, the over-reduction of PSI significantly stimulated CEF in the young leaves but not in the mature leaves. Taken together, within the first seconds after any increase in illumination, the stimulation of CEF favors the rapid lumen acidification and optimizes the PSI redox state in the young leaves, protecting PSI against photoinhibition under fluctuating light in field-grown plants.


Assuntos
Luz , Fotossíntese/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Prunus/crescimento & desenvolvimento , Prunus/fisiologia , Adaptação Fisiológica , Concentração de Íons de Hidrogênio , Oxirredução , Periodicidade , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/efeitos da radiação , Prótons , Prunus/efeitos da radiação , Tilacoides/fisiologia , Tilacoides/efeitos da radiação
11.
Neural Netw ; 120: 86-107, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31522826

RESUMO

Many complex actions are mentally pre-composed as plans that specify orderings of simpler actions. To be executed accurately, planned orderings must become active in working memory, and then enacted one-by-one until the sequence is complete. Examples include writing, typing, and speaking. In cases where the planned complex action is musical in nature (e.g. a choreographed dance or a piano melody), it appears to be possible to deploy two learned sequences at the same time, one composed from actions and a second composed from the time intervals between actions. Despite this added complexity, humans readily learn and perform rhythm-based action sequences. Notably, people can learn action sequences and rhythmic sequences separately, and then combine them with little trouble (Ullén & Bengtsson 2003). Related functional MRI data suggest that there are distinct neural regions responsible for the two different sequence types (Bengtsson et al. 2004). Although research on musical rhythm is extensive, few computational models exist to extend and inform our understanding of its neural bases. To that end, this article introduces the TAMSIN (Timing And Motor System Integration Network) model, a systems-level neural network model capable of performing arbitrary item sequences in accord with any rhythmic pattern that can be represented as a sequence of integer multiples of a base interval. In TAMSIN, two Competitive Queuing (CQ) modules operate in parallel. One represents and controls item order (the ORD module) and the second represents and controls the sequence of inter-onset-intervals (IOIs) that define a rhythmic pattern (RHY module). Further circuitry helps these modules coordinate their signal processing to enable performative output consistent with a desired beat and tempo.


Assuntos
Modelos Neurológicos , Rede Nervosa , Periodicidade , Encéfalo/fisiologia , Conectoma , Humanos , Imagem por Ressonância Magnética , Música , Percepção do Tempo
12.
Exp Brain Res ; 237(10): 2705-2713, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31420687

RESUMO

People commonly move along with auditory rhythms in the environment. Although the processes underlying such sensorimotor synchronisation have been extensively investigated in the previous research, the properties of auditory rhythms that facilitate the synchronisation remain largely unclear. This study explored the possible benefits of a continuity matching between auditory pacers and the movement produced as well as of a spatial pattern matching that has been previously demonstrated with visual pacers. Participants synchronised either finger tapping or forearm oscillations with either discrete or continuous pacers. The pacers had either a spatial pattern (left-right panning) that matched the movement pattern produced or no spatial pattern. The accuracy and variability of synchronisation were assessed by the mean and standard deviation of the asynchronies, respectively, between participant's movement and the pacers. Results indicated that synchronisation was more accurate and less variable for discrete pacers and continuous movement (i.e., forearm oscillations). The interaction between those two factors involved a more complex relationship than a simple continuity match benefit. Although synchronisation variability increased with continuous pacers for both types of movement, this increase was smaller for continuous movement than discrete movement, suggesting that continuous movement is more beneficial only for continuous pacers. Moreover, the results revealed limited benefits of spatial pattern matching on auditory-motor synchronisation variability, which might be due to lower spatial resolution of the auditory sensory modality. Together, these findings confirm that sensorimotor synchronisation is modulated by complex relations between pacer and movement properties.


Assuntos
Estimulação Acústica , Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Percepção do Tempo/fisiologia , Estimulação Acústica/métodos , Adulto , Feminino , Dedos/fisiologia , Humanos , Masculino , Periodicidade , Estimulação Luminosa/métodos , Adulto Jovem
13.
Scand J Med Sci Sports ; 29(12): 1866-1880, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430404

RESUMO

Repeated periodization of carbohydrate (CHO) intake using a diet-exercise strategy called the sleep-low model can potentially induce mitochondrial biogenesis and improve endurance performance in endurance-trained individuals. However, more studies are needed to confirm the performance-related effects and to investigate the sustained effects on maximal fat oxidation (MFO) rate and proteins involved in intramuscular lipid metabolism. Thirteen endurance-trained males (age 23-44 years; V ˙ O2 -max, 63.9 ± 4.6 mL·kg-1 ·min-1 ) were randomized into two groups: sleep-low (LOW-CHO) or high CHO availability (HIGH-CHO) in three weekly training blocks over 4 weeks. The acute metabolic response was investigated during 60 minutes of exercise within the last 3 weeks of the intervention. Pre- and post-intervention, 30-minute time-trial performance was investigated after a 90-minute pre-load, which as a novel approach included nine intense intervals (and estimation of MFO). Additionally, muscle biopsies (v. lateralis) were obtained to investigate expression of proteins involved in intramuscular lipid metabolism using Western blotting. During acute exercise, average fat oxidation rate was ~36% higher in LOW-CHO compared to HIGH-CHO (P = .03). This did not translate into sustained effects on MFO. Time-trial performance increased equally in both groups (overall time effect: P = .005). We observed no effect on intramuscular proteins involved in lipolysis (ATGL, G0S2, CGI-58, HSL) or fatty acid transport and ß-oxidation (CD-36 and HAD, respectively). In conclusion, the sleep-low model did not induce sustained effects on MFO, endurance performance, or proteins involved in intramuscular lipid metabolism when compared to HIGH-CHO. Our study therefore questions the transferability of acute effects of the sleep-low model to superior sustained adaptations.


Assuntos
Desempenho Atlético , Dieta/métodos , Carboidratos da Dieta/administração & dosagem , Resistência Física , Tecido Adiposo/metabolismo , Adulto , Atletas , Exercício Físico , Humanos , Metabolismo dos Lipídeos , Masculino , Músculo Esquelético/metabolismo , Consumo de Oxigênio , Periodicidade , Adulto Jovem
14.
J Fish Biol ; 95(4): 1072-1085, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31318045

RESUMO

The age of 296 juvenile scalloped hammerhead sharks Sphyrna lewini caught by several fisheries in the Mexican Pacific Ocean from March 2007 to September 2017 were estimated from growth band counts in thin-sectioned vertebrae. Marginal-increment analysis (MIA) and centrum-edge analysis (CEA) were used to verify the periodicity of formation of the growth bands, whereas elemental profiles obtained from LA-ICP-MS transect scans in vertebrae of 15 juveniles were used as an alternative approach to verify the age of the species for the first time. Age estimates ranged from 0 to 10+ years (42-158.7 cm total length; LT ). The index of average percentage error (IAPE 3.6%), CV (5.2%), bias plots and Bowker's tests of symmetry showed precise and low-biased age estimation. Both MIA and CEA indicated that in the vertebrae of juveniles of S. lewini a single translucent growth band was formed during winter (November-March) and an opaque band during summer (July-September), a period of faster growth, apparently correlated with a higher sea surface temperature. Peaks in vertebral P and Mn content spatially corresponded with the annual banding pattern in most of the samples, displaying 1.19 and 0.88 peaks per opaque band, respectively, which closely matched the annual deposition rate observed in this study. Although the periodicity of growth band formation needs to be verified for all sizes and ages representing the population of the species in the region, this demonstration of the annual formation of the growth bands in the vertebrae of juveniles should lead to a re-estimation of the growth parameters and productivity of the population to ensure that it is harvested at sustainable levels.


Assuntos
Periodicidade , Tubarões/crescimento & desenvolvimento , Coluna Vertebral/crescimento & desenvolvimento , Distribuição Animal , Animais , México , Oceano Pacífico
15.
Rinsho Shinkeigaku ; 59(7): 412-417, 2019 Jul 31.
Artigo em Japonês | MEDLINE | ID: mdl-31243246

RESUMO

A 53-year-old man with hypertension experienced sudden cardiopulmonary arrest. Ambulance crews detected ventricular fibrillation that responded to defibrillation. Cardiopulmonary resuscitation resulted in return of spontaneous circulation (ROSC) after 30 minutes. At admission to our hospital, he was in a comatose state. Therapeutic hypothermia was performed for two days with other supportive care. However, despite these therapies, he remained comatose, and a diagnosis of post-cardiac arrest syndrome (PCAS) was made. On the sixth hospital day, an electroencephalogram (EEG) showed lateralized periodic discharges (LPDs) in the right occipital area evolving to electrographic seizures. Over roughly 15 minutes, this evolution process repeated 10 times, demonstrating a cyclic seizure pattern. Intravenous administration of 10 mg diazepam resulted in temporal attenuation of the high-amplitude discharges followed by LPDs re-emergence accompanying a low-amplitude fast rhythm on the background activity (LPDs+). Antiepileptic drugs administration was continued, along with supportive care. He opened his eyes on the 11th hospital day, after which his general conditions showed a good recovery. He was discharged on the 30th day without any sequelae.


Assuntos
Eletroencefalografia , Parada Cardíaca/diagnóstico , Parada Cardíaca/fisiopatologia , Periodicidade , Convulsões/diagnóstico , Convulsões/fisiopatologia , Anticonvulsivantes/administração & dosagem , Arritmias Cardíacas/complicações , Vasoespasmo Coronário/complicações , Diazepam/administração & dosagem , Parada Cardíaca/tratamento farmacológico , Parada Cardíaca/etiologia , Humanos , Hipertensão , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Convulsões/tratamento farmacológico , Síndrome , Resultado do Tratamento
16.
BMC Bioinformatics ; 20(1): 340, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208316

RESUMO

BACKGROUND: As a highly efficient and specific gene regulation technology, RNAi has broad application fields and good prospects. The effect of RNAi enhances as the dosage of siRNA increases, while an exorbitant siRNA dosage will inhibit the RNAi effect. So it is crucial to formulate a dose-effect model to describe the degradation effects of the target mRNA at different siRNA dosages. RESULTS: In this work, a simple RNA interference model with hill kinetic function (Giulia Cuccato et al. (2011)) is extended. Firstly, by introducing both the degradation time delay τ1 of mRNA caused by siRNA and the transportation time delay τ2 of mRNA from the nucleus to the cytoplasm during protein translation, one acquires a novel delay differential equations (DDEs) model with physiology lags. Secondly, qualitative analyses are executed to identify regions of stability of the positive equilibrium and to determine the corresponding parameter scales. Next, the approximate period of the limit cycle at Hopf bifurcation points is computed. Furthermore we analyze the parameter sensitivity of the limit cycle. Finally, we propose an optimal strategy to select siRNA dosage which arouses significant silencing efficiency. CONCLUSIONS: Our researches indicate that when the dosage of siRNA is large, oscillating periods are identical for disparate number of siRNA target sites even if it greatly impacts the critical siRNA dosage which is the switch of oscillating behavior. Furthermore, parametric sensitivity analyses of limit cycle disclose that both of degradation lag and maximum degradation rate of mRNA due to RNAi are principal elements on determining periodic oscillation. Our explorations will provide evidence for gene regulation and RNAi.


Assuntos
Células Eucarióticas/metabolismo , Periodicidade , Interferência de RNA , Animais , Simulação por Computador , Humanos , Modelos Genéticos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética
17.
Biol Bull ; 236(3): 207-223, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31167088

RESUMO

Horseshoe crabs are harvested by the biomedical industry in order to create Limulus amebocyte lysate to test medical devices and pharmaceutical drugs for endotoxins. Most previous studies on the impacts of the biomedical bleeding process on horseshoe crabs have focused on mortality rates and sublethal impacts in the laboratory. In this study, we investigated the effects of the bleeding process on the behavior of horseshoe crabs after they had been released back into their natural environment. A total of 28 horseshoe crabs (14 control and 14 bled) were fitted with acoustic transmitters and released into the Great Bay Estuary, New Hampshire, during the spring of 2016. The acoustic tags transmitted information about the activity and depth of each animal, and these data were logged by an array of passive acoustic receivers. These data were collected from May to December 2016 and from March to October 2017. Bled animals approached mating beaches less than control animals during the first week after release, with the greatest differences between bled and control females. Bled animals also remained significantly deeper during the spawning season than control animals. However, overall, bled and control animals expressed similar biological rhythms and seasonal migrations. Thus, it appears as if the most obvious impacts of the bleeding process take place during the first one to two weeks after crabs are bled.


Assuntos
Hemolinfa/fisiologia , Caranguejos Ferradura/fisiologia , Migração Animal/fisiologia , Animais , Comportamento Animal/fisiologia , Ecossistema , New Hampshire , Periodicidade , Estações do Ano
18.
Exp Brain Res ; 237(8): 1981-1991, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152188

RESUMO

Both movement and neural activity in humans can be entrained by the regularities of an external stimulus, such as the beat of musical rhythms. Neural entrainment to auditory rhythms supports temporal perception, and is enhanced by selective attention and by hierarchical temporal structure imposed on rhythms. However, it is not known how neural entrainment to rhythms is related to the subjective experience of groove (the desire to move along with music or rhythm), the perception of a regular beat, the perception of complexity, and the experience of pleasure. In two experiments, we used musical rhythms (from Steve Reich's Clapping Music) to investigate whether rhythms that are performed by humans (with naturally variable timing) and rhythms that are mechanical (with precise timing), elicit differences in (1) neural entrainment, as measured by inter-trial phase coherence, and (2) subjective ratings of the complexity, preference, groove, and beat strength of rhythms. We also combined results from the two experiments to investigate relationships between neural entrainment and subjective perception of musical rhythms. We found that mechanical rhythms elicited a greater degree of neural entrainment than performed rhythms, likely due to the greater temporal precision in the stimulus, and the two types only elicited different ratings for some individual rhythms. Neural entrainment to performed rhythms, but not to mechanical ones, correlated with subjective desire to move and subjective complexity. These data, therefore, suggest multiple interacting influences on neural entrainment to rhythms, from low-level stimulus properties to high-level cognition and perception.


Assuntos
Estimulação Acústica/métodos , Percepção Auditiva/fisiologia , Música , Periodicidade , Prazer/fisiologia , Percepção do Tempo/fisiologia , Adulto , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Música/psicologia
19.
Neurosci Lett ; 708: 134331, 2019 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-31226362

RESUMO

Medical therapies applied to Parkinson's disease (PD) have advanced tremendously since the 1960's based on advances in our understanding of the underlying neurophysiology. Behavioral therapies, such as rhythmic auditory stimulation (RAS), have been developed more recently and demonstrated efficacy. However, the neural mechanisms of RAS are only vaguely understood. In this study, we examined the neurophysiology of RAS using magnetoencephalography (MEG) in a sample of older adults with (21 people) and without PD (23 participants). All participants underwent high-density MEG during a beat-based cued tapping task with rhythmic and non-rhythmic patterns, and the resulting data were analyzed using a Bayesian image reconstruction method. Complex wavelet based time-frequency decomposition was used to compute inter-trial phase locking factor (PLF) to auditory stimuli for left and right signal space projection vectors. Tapping with a rhythm compared to a non-rhythmic sequence resulted in differential brain activity in each group: (i) a greater activation of temporal, motor and parietal areas was found in healthy adults; (ii) a greater reliance on parietal and frontal gyri was found in PD participants. During rhythmic tapping, older adults without PD had significantly stronger neural activity in bilateral frontal, supplementary and primary motor areas compared to those with PD. Conversely, older adults with PD exhibited significantly stronger activity in the bilateral parietal regions, as well as the rolandic operculum and bilateral supramarginal gyri, relative to their healthy peers. These data suggest that RAS mobilizes diverse oscillatory networks; Healthy controls may shift to frontal areas mobilization whereas PD patients rely on parietal areas to a greater extent, which may reflect frontal network dysfunction with compensation in PD, and could serve as specific regions of interest for further RAS studies.


Assuntos
Doença de Parkinson/fisiopatologia , Desempenho Psicomotor , Estimulação Acústica , Adulto , Gânglios da Base/fisiopatologia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imagem por Ressonância Magnética , Magnetoencefalografia , Masculino , Doença de Parkinson/psicologia , Periodicidade
20.
Yale J Biol Med ; 92(2): 259-270, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31249487

RESUMO

Circadian disruption has been linked to markers for poor health outcomes in humans and animal models. What is it about circadian disruption that is problematic? One hypothesis is that phase resetting of the circadian system, which occurs in response to changes in environmental timing cues, leads to internal desynchrony within the organism. Internal desynchrony is understood as acute changes in phase relationships between biological rhythms from different cell groups, tissues, or organs within the body. Do we have strong evidence for internal desynchrony associated with or caused by circadian clock resetting? Here we review the literature, highlighting several key studies from measures of gene expression in laboratory rodents. We conclude that current evidence offers strong support for the premise that some protocols for light-induced resetting are associated with internal desynchrony. It is important to continue research to test whether internal desynchrony is necessary and/or sufficient for negative health impact of circadian disruption.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Periodicidade , Fotoperíodo , Animais , Relógios Circadianos/genética , Relógios Circadianos/efeitos da radiação , Ritmo Circadiano/genética , Ritmo Circadiano/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Luz , Núcleo Supraquiasmático/metabolismo , Núcleo Supraquiasmático/fisiopatologia , Núcleo Supraquiasmático/efeitos da radiação
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