Sleep cycle content and sleep cycle duration

1974 ◽  
Vol 36 ◽  
pp. 275-282 ◽  
Author(s):  
Vlasta Březinová
Keyword(s):  
Sleep Cycle ◽  
Cycle Duration

scholarly journals Video-EEG monitoring in diagnostics and treatment efficacy evaluation in newly-diagnosed generalized epilepsy in adults

2021 ◽  
Vol 13 (1) ◽  
pp. 21-32
Author(s):  
A. B. Kozhokaru ◽  
V. A. Karlov ◽  
P. N. Vlasov ◽  
A. S. Orlova
Keyword(s):  
Seizure Frequency ◽  
Treatment Efficacy ◽  
Activity Index ◽  
Epileptiform Activity ◽  
Sleep Cycle ◽  
Cycle Duration ◽  
Eeg Monitoring ◽  
Newly Diagnosed ◽  
Group I ◽  
Generalized Epilepsy

Introduction. Video-electroencephalography (EEG) monitoring (VEEGM) is an indispensable functional method in epileptology. However, virtually no trials on assessing efficacy of antiepileptic drugs (AED) by using VEEGM are available.Objective: to improve efficacy of EEG-diagnostics and evaluate the epileptiform activity index (EAI) in newly-diagnosed idiopathic generalized epilepsy in adult patients receiving  alproic acid and levetiracetam.Material and methods. T here w ere e nrolled 130 p atients: 6 0 (46.2%) m ales a nd 7 0 (53.8%) f emales w ith n ewlydiagnosedidiopathic generalized epilepsy (IGE), aged 22.51±8.9 years. All patients underwent VEEGM with quantitative EAI analysis at baseline visit and 1 3, 6 and 12 months later after treatment. Each seizure episode developed during the VEEGM study were assessed for type, time of seizure onset, relation to wake-sleep cycle, duration, ictal EEG pattern followed by diagnosing epileptic syndrome. Valproic acid and levetiracetam were used for initial therapy in groups per 65 patients in each. Treatment efficacy was assessed using parameters such as retention on therapy, absence of seizures, decrease of seizure frequency by >50%, decrease of seizure frequency by <50% – insufficient efficacy.Results. It was found that seizures during baseline VEEGM were recorded in 43.1% (n=56) patients, who were assigned to group 1, whereas remaining 74 (56.9%) patients were assigned to group 2. EAI was significantly higher in patients with seizures recoded at baseline VEEGM, compared to those lacking seizure episodes during initial VEEGM (p<0,001), mean EAI was also higher in group I at second (p<0.001) and third (p<0.001) visits. EAI magnitude at 6 and 12 months of study became virtually comparable in all groups and did not depend on AED prescribed. Treatment efficacy was higher in patients with IGE, with no  eizures recorded during the initial VEEGM.Conclusion. Long-term VEEGM allows unbiased assessment of treatment dynamics based on EAI analysis. The first 6 months of initial treatment titration in represent most crucial period for patients with newly-diagnosed IGE.

scholarly journals EEG sleep macrostructure and sleep spindles in early infancy

SLEEP ◽  
2021 ◽  
Author(s):  
Soraia Ventura ◽  
Sean R Mathieson ◽  
John M O’Toole ◽  
Vicki Livingstone ◽  
Mary-Anne Ryan ◽  
...  
Keyword(s):  
Spectral Power ◽  
Brain Maturation ◽  
Normative Values ◽  
Sleep Cycle ◽  
Sleep Spindles ◽  
Cycle Duration ◽  
Term Infants ◽  
Recording Time ◽  
Future Studies ◽  
Symmetry Index

Abstract Study Objectives Sleep features in infancy are potential biomarkers for brain maturation but poorly characterised. We describe normative values for sleep macrostructure and sleep spindles at 4-5 months of age. Methods Healthy term infants were recruited at birth and had daytime sleep EEGs at 4-5 months. Sleep staging was performed and 5 features were analysed. Sleep spindles were annotated and 7 quantitative features were extracted. Features were analysed across sex, recording time (am/pm), infant age and from first to second sleep cycles. Results We analysed sleep recordings from 91 infants, 41% girls. Median (IQR) macrostructure results: sleep duration 49.0 (37.8-72.0) minutes (n=77); first sleep cycle duration 42.8 (37.0 – 51.4) minutes; REM percentage 17.4 (9.5 - 27.7)% (n=68); latency to REM 36.0 (30.5-41.1) minutes (n=66). First cycle median (IQR) values for spindle features: number 241.0 (193.0-286.5), density 6.6 (5.7-8.0) spindles.min -1(n=77); mean frequency 13.0 (12.8-13.3) Hz, mean duration 2.9 (2.6-3.6)s, spectral power 7.8 (4.7-11.4)µV 2, brain symmetry index 0.20 (0.16-0.29), synchrony 59.5 (53.2-63.8)% (n=91). In males, spindle spectral power (µV 2) is 24.5% lower (p=0.032) and brain symmetry index 24.2% higher than females (p=0.011) when controlling for gestational and postnatal age and timing of the nap. We found no other significant associations between studied sleep features and sex, recording time (am/pm), or age. Spectral power decreased (p&lt;0.001) on the second cycle. Conclusion This normative data may be useful for comparison with future studies of sleep dysfunction and atypical neurodevelopment in infancy.

NEW DATA CONCERNING THE ROLE PLAYED BY PROGESTERONE IN THE CONTROL OF FOLLICULAR GROWTH IN THE RAT

1974 ◽  
Vol 75 (3) ◽  
pp. 569-578 ◽  
Author(s):  
G. Buffler ◽  
S. Roser
Keyword(s):  
Wistar Rats ◽  
Venous Blood ◽  
Oestrous Cycle ◽  
Female Rats ◽  
Cycle Duration ◽  
Follicular Growth ◽  
The Third ◽  
Female Wistar Rats

ABSTRACT The mechanisms involved in the prolongation of the oestrous cycle following LH administration were studied in 4-day cyclic female Wistar rats. In females injected with LH on the morning of dioestrus I there was an increase in ovarian venous blood progesterone as compared with non-injected animals. In both LH-treated females, and those injected with progesterone on the morning of dioestrus I, a slowing up in follicular growth was observed from the afternoon of dioestrus I. The size of follicles greater than 400 urn present in LH or progesterone injected animals on the third day of cycle was similar to the size reached by the same range of follicles in non-injected animals on the second day of the cycle. Hence, the increase in endogenous ovarian progesterone elicited by LH was considered as the cause of the slowing up of follicular growth and therefore of the lengthening of the oestrous cycle duration in female rats injected with LH at the beginning of 4-day cycle.

scholarly journals Toward asleep DBS: cortico-basal ganglia spectral and coherence activity during interleaved propofol/ketamine sedation mimics NREM/REM sleep activity

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jing Guang ◽  
Halen Baker ◽  
Orilia Ben-Yishay Nizri ◽  
Shimon Firman ◽  
Uri Werner-Reiss ◽  
...  
Keyword(s):  
Basal Ganglia ◽  
Rem Sleep ◽  
Standard Procedure ◽  
Low Frequency ◽  
Nrem Sleep ◽  
Sleep Cycle ◽  
Advanced Parkinson’S Disease ◽  
Low Frequency Power ◽  
The Brain ◽  
Frequency Power

AbstractDeep brain stimulation (DBS) is currently a standard procedure for advanced Parkinson’s disease. Many centers employ awake physiological navigation and stimulation assessment to optimize DBS localization and outcome. To enable DBS under sedation, asleep DBS, we characterized the cortico-basal ganglia neuronal network of two nonhuman primates under propofol, ketamine, and interleaved propofol-ketamine (IPK) sedation. Further, we compared these sedation states in the healthy and Parkinsonian condition to those of healthy sleep. Ketamine increases high-frequency power and synchronization while propofol increases low-frequency power and synchronization in polysomnography and neuronal activity recordings. Thus, ketamine does not mask the low-frequency oscillations used for physiological navigation toward the basal ganglia DBS targets. The brain spectral state under ketamine and propofol mimicked rapid eye movement (REM) and Non-REM (NREM) sleep activity, respectively, and the IPK protocol resembles the NREM-REM sleep cycle. These promising results are a meaningful step toward asleep DBS with nondistorted physiological navigation.

scholarly journals Melatonin in Wine and Beer: Beneficial Effects

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 343
Author(s):  
Javier Marhuenda ◽  
Débora Villaño ◽  
Raúl Arcusa ◽  
Pilar Zafrilla
Keyword(s):  
Intracellular Signaling ◽  
Plasma Concentrations ◽  
Radical Scavenging ◽  
Direct Interaction ◽  
Melatonin Receptors ◽  
Current Evidence ◽  
Sleep Cycle ◽  
Beneficial Effects ◽  
Neuroprotective Actions ◽  
Radical Scavenging Properties

Melatonin is a hormone secreted in the pineal gland with several functions, especially regulation of circadian sleep cycle and the biological processes related to it. This review evaluates the bioavailability of melatonin and resulting metabolites, the presence of melatonin in wine and beer and factors that influence it, and finally the different benefits related to treatment with melatonin. When administered orally, melatonin is mainly absorbed in the rectum and the ileum; it has a half-life of about 0.45–1 h and is extensively inactivated in the liver by phase 2 enzymes. Melatonin (MEL) concentration varies from picograms to ng/mL in fermented beverages such as wine and beer, depending on the fermentation process. These low quantities, within a dietary intake, are enough to reach significant plasma concentrations of melatonin, and are thus able to exert beneficial effects. Melatonin has demonstrated antioxidant, anticarcinogenic, immunomodulatory and neuroprotective actions. These benefits are related to its free radical scavenging properties as well and the direct interaction with melatonin receptors, which are involved in complex intracellular signaling pathways, including inhibition of angiogenesis and cell proliferation, among others. In the present review, the current evidence on the effects of melatonin on different pathophysiological conditions is also discussed.

scholarly journals Positive Feedback Between PU.1 and the Cell Cycle Controls Myeloid Differentiation

Science ◽  
2013 ◽  
Vol 341 (6146) ◽  
pp. 670-673 ◽  
Author(s):  
Hao Yuan Kueh ◽  
Ameya Champhekar ◽  
Stephen L. Nutt ◽  
Michael B. Elowitz ◽  
Ellen V. Rothenberg
Keyword(s):  
Cell Cycle ◽  
Cell Fate ◽  
Positive Feedback ◽  
Regulatory Gene ◽  
Control Cell ◽  
Stem Cell Differentiation ◽  
Myeloid Differentiation ◽  
Cycle Duration ◽  
Gene Circuits ◽  
Cell Cycles

Regulatory gene circuits with positive-feedback loops control stem cell differentiation, but several mechanisms can contribute to positive feedback. Here, we dissect feedback mechanisms through which the transcription factor PU.1 controls lymphoid and myeloid differentiation. Quantitative live-cell imaging revealed that developing B cells decrease PU.1 levels by reducing PU.1 transcription, whereas developing macrophages increase PU.1 levels by lengthening their cell cycles, which causes stable PU.1 accumulation. Exogenous PU.1 expression in progenitors increases endogenous PU.1 levels by inducing cell cycle lengthening, implying positive feedback between a regulatory factor and the cell cycle. Mathematical modeling showed that this cell cycle–coupled feedback architecture effectively stabilizes a slow-dividing differentiated state. These results show that cell cycle duration functions as an integral part of a positive autoregulatory circuit to control cell fate.

scholarly journals Assessment of Selected Spatio-Temporal Gait Parameters on Subjects with Pronated Foot Posture on the Basis of Measurements Using OptoGait. A Case-Control Study

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2805
Author(s):  
Inmaculada Requelo-Rodríguez ◽  
Aurora Castro-Méndez ◽  
Ana María Jiménez-Cebrián ◽  
María Luisa González-Elena ◽  
Inmaculada C. Palomo-Toucedo ◽  
...  
Keyword(s):  
Gait Cycle ◽  
Population Aging ◽  
Adult Population ◽  
Control Group ◽  
Cycle Duration ◽  
Foot Posture ◽  
Complex Control System ◽  
Risk Of Falls ◽  
Spatio Temporal ◽  
Asymptomatic Subjects

Walking is part of daily life and in asymptomatic subjects it is relatively easy. The physiology of walking is complex and when this complex control system fails, the risk of falls increases. As a result, gait disorders have a major impact on the older adult population and have increased in frequency as a result of population aging. Therefore, the OptoGait sensor is intended to identify gait imbalances in pronating feet to try to prevent falling and injury by compensating for it with treatments that normalize such alteration. This study is intended to assess whether spatiotemporal alterations occur in the gait cycle in a young pronating population (cases) compared to a control group (non-pronating patients) analyzed with OptoGait. Method: a total of n = 142 participants consisting of n = 70 cases (pronators) and n = 72 healthy controls were studied by means of a 30 s treadmill program with a system of 96 OptoGait LED sensors. Results: Significant differences were found between the two groups and both feet in stride length and stride time, gait cycle duration and gait cadence (in all cases p < 0.05). Conclusions: pronating foot posture alters normal gait patterns measured by OptoGait; this finding presents imbalance in gait as an underlying factor. Prevention of this alteration could be considered in relation to its relationship to the risk of falling in future investigations.

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