Effects of sleep deprivation on sleep and sleep electroencephalogram in secretin-receptor knockout mice.

Recent studies has consistently demonstrated a relationship between secretin and autism-like behavior in mice. Therefore, secretin-receptor knockout (SCTR-KO) mice are used to study autism. However, with respect to humans, some studies have reported that secretin administration could improve autistic symptoms in contrast to other studies.

Effectiveness of seasonal influenza vaccine in adult Japanese workers, 2017-2020.

Background: Previous studies have not estimated vaccine effectiveness (VE) against influenza in the working-age Japanese population. In this study, we determined VE in adult workers at a Japanese company.

Methods: We estimated VE based on self-reported data regarding influenza infections and vaccinations in employees of an auto parts manufacturing company during three influenza seasons from 2017 to 2020.

Subjective and objective assessments after a change from a 4-crew, 12-h shift to a 3-crew, 12-h shift schedule: an observational study.

Purpose: To clarify the subjective and objective impacts of a change in a 12-h shift schedule, involving a reduction in the number of crews, on workers at an electronic parts production company.

Methods: Forty-two workers participated in this study. Subjective indicators (e.

Increased oxytocin-monomeric red fluorescent protein 1 fluorescent intensity with urocortin-like immunoreactivity in the hypothalamo-neurohypophysial system of aged transgenic rats.

To visualize oxytocin in the hypothalamo-neurohypophysial system, we generated a transgenic rat that expresses the oxytocin-monomeric red fluorescent protein 1 (mRFP1) fusion gene. In the present study, we examined the age-related changes of oxytocin-mRFP1 fluorescent intensity in the posterior pituitary (PP), the supraoptic nucleus (SON) and the paraventricular nucleus (PVN) of transgenic rats. The mRFP1 fluorescent intensities were significantly increased in the PP, the SON and the PVN of 12-, 18- and 24-month-old transgenic rats in comparison with 3-month-old transgenic rats.

Visual recognition memory test performance was improved in older adults by extending encoding time and repeating test trials.

Objectives: The aim of this study was to investigate whether the combination of extension of the encoding time and repetition of a test trial would improve the visual recognition memory performance in older adults.

Methods: We evaluated visual memory performance in young and older adults on a Yes-No recognition memory test under four different conditions. The conditions consisted of combinations of encoding times of two and four seconds (E2 and E4) and first and second retrieval practice test trials (T1 and T2): E2T1, E2T2, E4T1 and E4T2.

[Sleep problems in occupational health].

It is important for workers to maintain a high quality of sleep to obtain their best performance at the workplace and in daily life. Insufficient sleep and/or dyssynchrony between internal clock and external light/dark cycles cause daytime sleepiness, and could result in a reduction of the working efficiency. Sleepiness may sometimes cause enormous economic and social losses.

Effects of paraxanthine and caffeine on sleep, locomotor activity, and body temperature in orexin/ataxin-3 transgenic narcoleptic mice.

Study Objective: Caffeine, an adenosine A1 and A2a receptor antagonist, is a widely consumed stimulant and also used for the treatment of hypersomnia; however, the wake-promoting potency of caffeine is often not strong enough, and high doses may induce side effects. Caffeine is metabolized to paraxanthine, theobromine, and theophylline. Paraxanthine is a central nervous stimulant and exhibits higher potency at A1 and A2 receptors, but has lower toxicity and lesser anxiogenic effects than caffeine.

Amyloid-beta dynamics are regulated by orexin and the sleep-wake cycle.

Amyloid-beta (Abeta) accumulation in the brain extracellular space is a hallmark of Alzheimer's disease. The factors regulating this process are only partly understood. Abeta aggregation is a concentration-dependent process that is likely responsive to changes in brain interstitial fluid (ISF) levels of Abeta.

The transcriptional repressor DEC2 regulates sleep length in mammals.

Sleep deprivation can impair human health and performance. Habitual total sleep time and homeostatic sleep response to sleep deprivation are quantitative traits in humans. Genetic loci for these traits have been identified in model organisms, but none of these potential animal models have a corresponding human genotype and phenotype.

Central AMPK contributes to sleep homeostasis in mice.

AMP-activated protein kinase (AMPK) is an energy-sensing molecular signal involved in glucose and lipid metabolism. The known interaction of sleep with energy metabolism led us to investigate the role of central AMPK in sleep homeostasis. Sleep deprivation (SD) for 6 h increased p-AMPK protein in the hypothalamus and also increased the mRNA level of Ca(2+)/calmodulin (CaM)-dependent protein kinase kinase beta (CaMKK2), an activator of AMPK, and carnitine palmitoyltransferase 1 (CPT1), a downstream signaling factor of AMPK.

Specificity of direct transition from wake to REM sleep in orexin/ataxin-3 transgenic narcoleptic mice.

To create operational criteria for polygraphic assessments of direct transitions from wake to REM sleep (DREM), as a murine analog of human cataplexy, we have analyzed DREM episodes in congenic lines of orexin/ataxin-3 transgenic [TG] mice and wild-type littermates. The sleep stage of each 10-second epoch was visually scored using our standard criteria. Specificity of DREM for narcoleptic TG mice and sensitivity to detect DREM was evaluated using different DREM criteria.

Hypocretin receptor expression in canine and murine narcolepsy models and in hypocretin-ligand deficient human narcolepsy.

Study Objective: To determine whether hypocretin receptor gene (hcrtR1 and hcrtR2) expression is affected after long-term hypocretin ligand loss in humans and animal models of narcolepsy.

Design: Animal and human study. We measured hcrtR1 and hcrtR2 expression in the frontal cortex and pons using the RT-PCR method in murine models (8-week-old and 27-week-old orexin/ataxin-3 transgenic (TG) hypocretin cell ablated mice and wild-type mice from the same litter, 10 mice for each group), in canine models (8 genetically narcoleptic Dobermans with null mutations in the hcrtR2, 9 control Dobermans, 3 sporadic ligand-deficient narcoleptics, and 4 small breed controls), and in humans (5 narcolepsy-cataplexy patients with hypocretin deficiency (average age 77.

Sleep and EEG features in genetic models of Down syndrome.

Down syndrome is characterized by a host of behavioral abnormalities including sleep disturbances. Sleep and EEG was studied at the age of 3 months in two mouse models of the condition, Ts65Dn and Ts1Cje, carrying one extra copy of partially overlapping segments of the mmu chromosome 16 (equivalent to the human chromosome 21). We found that the Ts65Dn mice showed increased waking amounts at the expense of non-REM sleep, increased theta power during sleep and a delayed sleep rebound after sleep deprivation.

CSF histamine levels in rats reflect the central histamine neurotransmission.

Reduced cerebrospinal fluid (CSF) histamine levels were found in human hypersomnia. To evaluate the functional significance of changes in CSF histamine levels, we measured the levels in rats across 24h, after the administration of wake-promoting compounds modafinil, amphetamine, and thioperamide, and after sleep deprivation and food deprivation. Thioperamide significantly increased CSF histamine levels with little effects on locomotor activation.

CSF orexin-A/hypocretin-1 concentrations in patients with intracerebral hemorrhage (ICH).

Orexins/hypocretins are neuropeptides that have various physiological effects, including the regulation of both the feeding behavior neuroendocrine functions and sleep-wakefulness cycle. Recent studies have suggested that the orexin system may also be involved in neuronal damage in the clinical setting and animal experiments. The aim of this study was to examine the role of the hypothalamic orexin-A/hypocretin-1 system in patients with intracerebral hemorrhage (ICH).

Neuropeptides as possible targets in sleep disorders: special emphasis on hypocretin-deficient narcolepsy.

Sleep disorders are disturbances of usual sleep patterns or behaviors caused by deregulation of neuronal synchronicity and of the balance of the neurotransmitter system involved in sleep regulation. Insomnia and hypersomnia are frequent sleep disorders, and these are most often treated pharmacologically with hypnotics and wake-promoting compounds. These compounds act on classical neurotransmitter systems, such as benzodiazepines on gamma amino butyric acid (GABA)(A) receptors, and amphetamine-like stimulants on monoaminergic terminals to modulate neurotransmission.

Neuropeptides as possible targets in sleep disorders.

Insomnia and hypersomnia are frequent sleep disorders, and they are most often treated pharmacologically with hypnotics and wake-promoting compounds. These compounds act on classical neurotransmitter systems, such as benzodiazepines on GABA-A receptors, and amfetamine-like stimulants on monoaminergic terminals to modulate neurotransmission. In addition, acetylcholine, amino acids, lipids and proteins (cytokines) and peptides, are known to significantly modulate sleep and are, therefore, possibly involved in the pathophysiology of some sleep disorders.

Sex difference in body weight gain and leptin signaling in hypocretin/orexin deficient mouse models.

Recent studies in human and animal models of narcolepsy have suggested that obesity in narcolepsy may be due to deficiency of hypocretin signaling, and is also under the influence of environmental factors and the genetic background. In the current study, using two hypocretin/orexin deficient narcoleptic mouse models (i.e.

Change in intrathoracic pressure in rats with spontaneous and controlled ventilation during microgravity by parabolic flight.

We previously reported that the intrathoracic pressure (ITP) decreases and the transmural pressure of the aortic wall (TMP) increases during 4.5 s of microgravity (muG) induced by free drop. To examine the ITP response to a longer period of muG in the absence of the respiratory rate (RR) decrease, i.

Sequence of forebrain activation induced by intraventricular injection of hypertonic NaCl detected by Mn2+ contrasted T1-weighted MRI.

In order to define the sequence of forebrain activation involved in osmoregulation, central activation in response to intracerebroventricular injection of NaCl solution (10 microl of 0.15, 0.5, or 1.

The roles of midbrain and diencephalic dopamine cell groups in the regulation of cataplexy in narcoleptic Dobermans.

Cataplexy, an emotion-triggered sudden loss of muscle tone specific to narcolepsy, is tightly associated with hypocretin deficiency. Using hypocretin receptor 2 gene (hcrtr 2)-mutated narcoleptic Dobermans, we have previously demonstrated that altered dopamine (DA) D(2/3) receptor mechanisms in mesencephalic DA nuclei are important for the induction of cataplexy. In the current study, we also found that the administration of D(2/3) agonists into diencephalic dopaminergic cell groups, including the area dorsal to the ventral tegmental area (DRVTA) and the periventricular gray (PVG) matter of the caudal thalamus (corresponding to area A11), significantly aggravated cataplexy in hcrtr 2-mutated narcoleptic Dobermans.

Acute hemodynamic responses in the head during microgravity induced by free drop in anesthetized rats.

To examine acute hemodynamic responses to microgravity (microG) in the head, we measured carotid artery pressure (CAP) and jugular vein pressure (JVP) to calculate cephalic perfusion pressure (CPP = CAP - JVP) and recorded images of microvessels in the iris to evaluate capillary blood flow velocity (CBFV) and capillary diameter (CD) in anesthetized rats during 4.5 s of microG induced by free drop. Rats were placed in 30 degrees head-up whole body-tilted (HU, n = 7) or horizontal (flat, n = 6) position.

Effects of IV and ICV hypocretin-1 (orexin A) in hypocretin receptor-2 gene mutated narcoleptic dogs and IV hypocretin-1 replacement therapy in a hypocretin-ligand-deficient narcoleptic dog.

Study Objectives: Using two different canine models of narcolepsy, we evaluated the therapeutic effects of hypocretin-1 on cataplexy and sleep.

Measurements And Results: Intracerebroventricular administration of hypocretin-1 (10 and 30 nmol per dog) but not intravenous administration (up to 6 microg/kg) induced significant wakefulness in control dogs. However, hypocretin-1 had no effect on cataplexy or wakefulness in hypocretin receptor-2 gene (Hcrtr2) mutated narcoleptic Dobermans.

Cerebral hemodynamics during microgravity.

As one of the causes of the space adaptation syndrome, an increased intracranial pressure due to the cephalad fluid shift is suggested. In the present study, we measured intracranial pressure (ICP), aortic pressure and cerebral flow velocity (CFV) in anesthetized rats (n=5) during 4.5 sec of microgravity induced by free drop.