1,721,115 research outputs found
Putative Animal Models of Restless Legs Syndrome: A Systematic Review and Evaluation of Their Face and Construct Validity.
Full text linkRestless legs syndrome (RLS) is a sensorimotor disorder that severely affects sleep. It is characterized by an urge to move the legs, which is often accompanied by periodic limb movements during sleep. RLS has a high prevalence in the population and is usually a life-long condition. While its origins remain unclear, RLS is initially highly responsive to treatment with dopaminergic agonists that target D2-like receptors, in particular D2 and D3, but the long-term response is often unsatisfactory. Over the years, several putative animal models for RLS have been developed, mainly based on the epidemiological and neurochemical link with iron deficiency, treatment efficacy of D2-like dopaminergic agonists, or genome-wide association studies that identified risk factors in the patient population. Here, we present the first systematic review of putative animal models of RLS, provide information about their face and construct validity, and report their role in deciphering the underlying pathophysiological mechanisms that may cause or contribute to RLS. We propose that identifying the causal links between genetic risk factors, altered organ functions, and changes to molecular pathways in neural circuitry will eventually lead to more effective new treatment options that bypass the side effects of the currently used therapeutics in RLS, especially for long-term therapy
REM Sleep EEG Instability in REM Sleep Behavior Disorder and Clonazepam Effects
Full text linkWe aimed to analyze quantitatively REM sleep EEG in controls, drug-naïve idiopathic REM sleep behavior disorder patients (iRBD), and iRBD patients treated with clonazepam
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Recent developments in automatic scoring of rodent sleep
No full textSleep research carried out on rat and mouse model led to the publication of more than 5000 papers in the last 15 years, of which more than 500 in 2014. Wake-sleep scoring represents a crucial step of the work performed in pre-clinical sleep laboratories; it is a time consuming task and a potential source of errors affecting research outcomes. Several algorithms have been developed to perform automatic sleep scoring. Automatic scoring can accelerate the work of researchers substantially. Moreover, the use of sleep scoring algorithms facilitates the direct comparison of the results produced in different laboratories, with clear advantages from the viewpoint of the advancement of science and reduction of the number of animals used for research. The intent of this review is to provide the readers with the last developments in scoring in rodent sleep and to stress about the need of a cross-lab and cross-species validated algorithm
Brain-heart interactions: Physiology and clinical implications
No full textThe brain controls the heart directly through the sympathetic and parasympathetic branches of the autonomic nervous system, which consists of multi-synaptic pathways from myocardial cells back to peripheral ganglionic neurons and further to central preganglionic and premotor neurons. Cardiac function can be profoundly altered by the reflex activation of cardiac autonomic nerves in response to inputs from baro-, chemo-, nasopharyngeal and other receptors as well as by central autonomic commands, including those associated with stress, physical activity, arousal and sleep. In the clinical setting, slowly progressive autonomic failure frequently results from neurodegenerative disorders, whereas autonomic hyperactivity may result from vascular, inflammatory or traumatic lesions of the autonomic nervous system, adverse effects of drugs and chronic neurological disorders. Both acute and chronic manifestations of an imbalanced brain-heart interaction have a negative impact on health. Simple, widely available and reliable cardiovascular markers of the sympathetic tone and of the sympathetic-parasympathetic balance are lacking. A deeper understanding of the connections between autonomic cardiac control and brain dynamics through advanced signal and neuroimage processing may lead to invaluable tools for the early detection and treatment of pathological changes in the brain-heart interaction
Reply to “Letter to the editor: Does low-frequency power of heart rate variability correlate with cardiac sympathetic tone in normal sheep?”
No full textHigh amplitude theta wave bursts: A novel electroencephalographic feature of REM sleep and cataplexy
No full textIn 2012, high amplitude theta wave bursts (HATs) were originally described during REMS and cataplexy in ORX-deficient mice as a novel neurophysiological correlate of narcolepsy (Bastianini et al., 2012). This finding was replicated the following year by Vassalli et al. in both ORX-deficient narcoleptic mice and narcoleptic children during cataplexy episodes (Vassalli et al., 2013). The relationship between HATs and narcolepsy-cataplexy in mice and patients indicates that the lack of ORX peptides is responsible for this abnormal EEG activity, the physiological meaning of which is still unknown. This review aimed to explore different phasic EEG events previously described in the published literature in order to find analogies and differences with HATs observed in narcoleptic mice and patients. We found similarities in terms of morphology, frequency and duration between HATs and several physiological (mu and wicket rhythms, sleep spindles, saw-tooth waves) or pathological (SWDs, HVSs, bursts of polyphasic complexes EEG complexes reported in a mouse model of CJD, and BSEs) EEG events. However, each of these events also shows significant differences from HATs, and thus cannot be equaled to them. The available evidence thus suggests that HATs are a novel neurophysiological phenomenon. Further investigations on HATs are required in order to investigate their physiological meaning, to individuate their brain structure(s) of origin, and to clarify the neural circuits involved in their manifestation
Brain capillary perfusion in the spontaneously hypertensive rat during the wake-sleep cycle
No full textHypertension is accompanied by circulatory changes in the brain and in other vascular districts; at disease onset, these changes may be largely functional and dependent on metabolic and vegetative drives. The wake-sleep cycle is a major physiological source of ultradian variability in autonomic function and in cerebral blood flow and metabolism. Aim of the study was to investigate whether sleep induces functional changes in the brain microcirculation in the developing hypertensive state. The fraction of brain capillaries perfused by plasma (perfused/anatomical capillaries) was assessed in young (8-10 weeks) spontaneously hypertensive rats (SHR) during quiet wakefulness, quiet sleep and active sleep. The density of anatomical capillaries was assessed in two groups of animals using both a histochemical method (alkaline phosphatase, AP, for morphometric measurements) and an immunofluorescence method (anti-fibronectin antibodies, FN, to detect all existing capillaries). The density of perfused capillaries was determined by intravascular injection of a fluorescent marker. The fraction of anatomical capillaries perfused by plasma was always close to maximal (0.96-0.97), without significant variations among the states of the wake-sleep cycle, and was the same for AP-stained and FN-stained sections. Data thus indicate that in this model of essential hypertension no functional changes in plasma perfusion of cerebral capillaries occur in the early stages of the disease
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