Metabolic consequences of sleep restriction in rats

Metabole ziekten als overgewicht en type 2 diabetes komen steeds meer voor in de Westerse wereld. De hoeveelheid slaap is de laatste jaren juist sterk afgenomen. Recent onderzoek heeft aangetoond dat een tekort aan slaap of een verstoring van de slaap een rol kan spelen bij de ontwikkeling van deze metabole ziekten. In dit proefschrift is onderzocht wat het effect is van chronisch slaaptekort op de metabole regulatie in ratten. We hebben laten zien dat verstoorde slaap leidt tot een verhoging van bloedglucose waarden. Wij concludeerden hieruit dat de ratten glucose-intolerant zijn geworden. Dit wordt gezien als de eerste stap in de ontwikkeling van type 2 diabetes. Verder leidt slaaptekort in ratten vaak tot een verlaging van lichaamsgewicht. Wij hebben laten zien dat dit wordt veroorzaakt door een verhoging van de energie-uitgave tijdens slaaptekort. Echter, als de periodes van slaaptekort worden afgewisseld met periodes van rust komen de ratten aan in gewicht. Deze afwisseling van slaaptekort en herstelslaap is iets wat in het dagelijkse leven vaak voorkomt: slaaptekort tijdens de week, en bijslapen in het weekend. Eerdere studies hebben laten zien dat herstelslaap van belang is voor allerlei physiologische processen, maar nu hebben wij laten zien dat de continue afwisseling voor een lange periode schadelijk kan zijn voor de energie huishouding en daardoor een risicofactor kan zijn voor de ontwikkeling van metabole ziekten

Chronic Sleep Disturbance Impairs Glucose Homeostasis in Rats

Epidemiological studies have shown an association between short or disrupted sleep and an increased risk for metabolic disorders. To assess a possible causal relationship, we examined the effects of experimental sleep disturbance on glucose regulation in Wistar rats under controlled laboratory conditions. Three groups of animals were used: a sleep restriction group (RS), a group subjected to moderate sleep disturbance without restriction of sleep time (DS), and a home cage control group. To establish changes in glucose regulation, animals were subjected to intravenous glucose tolerance tests (IVGTTs) before and after 1 or 8 days of sleep restriction or disturbance. Data show that both RS and DS reduce body weight without affecting food intake and also lead to hyperglycemia and decreased insulin levels during an IVGTT. Acute sleep disturbance also caused hyperglycemia during an IVGTT, yet, without affecting the insulin response. In conclusion, both moderate and severe disturbances of sleep markedly affect glucose homeostasis and body weight control

Image Processing Based Horizon Sensor for Estimating the Orientation of Sounding Rockets, Launch Vehicles and Spacecraft

The paper describes how the attitude of a sounding rocket, launch vehicle or satellite with respect to the Earth can be estimated from camera images of the Earth horizon. Details about detecting the horizon in the camera image, fitting hyperbolae or ellipses to the detected horizon curve and deriving the Earth nadir vector and the corresponding error covariance from the fitted conic section are given. The presented method works at low heights, where the projected horizon mostly appears to be hyperbolic, as well as at large heights, where the projected horizon mostly appears to be elliptic and it is irrelevant if the Earth is fully or only partially in the field-of-view of the camera. In fact, the method can be universally used to estimate the direction vectors and attitude with respect to any spherical celestial body such as the Sun or Moon. Using the example of a sounding rocket mission with two cameras aboard, it is illustrated how the estimates of the Earth nadir and the Sun direction vectors are fused with the measurements of a strapdown inertial measurement unit and a GPS receiver to obtain an accurate and continuous estimate of the three-dimensional orientation of the sounding rocket with respect to the Earth

Reconstruction of the 3D Orientation of a Spinning Sounding Rocket by Detecting the Earth’s Horizon and Sun on Onboard Camera Images

The paper describes the reconstruction of the 3D orientation of the spinning PMWE2F sounding rocket solely from the images of a side-looking camera. The Earth nadir vector, pointing to the centre of the Earth, is derived from the detected Earth’s horizon hyperbolae, and the Sun direction vector, pointing to the Sun, is derived from the detected Sun ellipses. The orientation is estimated using the TRIAD method when the Earth’s horizon and Sun are simultaneously visible, and by determining only two rotational degrees of freedom (DoF) and time interpolation of the third DoF in the meantime when only the Earth’s horizon is visible

Risk factors and oral health-related quality of life: A case–control comparison between patients after a first-episode psychosis and people from general population

INTRODUCTION: No research is available about the oral health risk factors and oral health-related quality of life (OHRQoL) in patients diagnosed with a psychotic disorder. AIM: To compare oral health risk factors and OHRQoL in patients diagnosed with a psychotic disorder (first-episode) to people with no history of psychotic disorder. METHOD: A case-control comparison (1:2) multivariable linear regression analysis and an estimation of prevalence of impact on OHRQoL. RESULTS: Patients diagnosed with a psychotic disorder (first-episode) have lower OHRQoL with more associated risk factors. Of the patients diagnosed with a psychotic disorder (first-episode), 14.8% reported a negative impact on OHRQoL, higher than the prevalence of 1.8% found in people from the general population. DISCUSSION: The high prevalence rate of a negative impact on OHRQoL in patients diagnosed with a psychotic disorder (first-episode) shows the importance of acting at an early stage to prevent a worse outcome. IMPLICATIONS FOR PRACTICE: The findings highlight the need for oral health interventions in patients diagnosed with a psychotic disorder (first-episode). Mental health nurses, as one of the main health professionals supporting the health of patients diagnosed with a mental health disorder, can support oral health (e.g. assess oral health in somatic screening) in order to improve the OHRQoL

Changing Shapes of Care:Expressions of Filial Piety among Second-generation Chinese in the Netherlands

This study explored perceptions of filial care among second-generation Chinese immigrants in the Netherlands. The provision of filial help or care can be regarded as a cultural phenomenon known as filial piety and it can be considered within the broad scope of caregiving as "family care". Fifteen interviews were conducted, and a thematic analysis was applied. The findings showed that care was given in the form of language brokering, information inquiry, home visits, and facilitative and social support. Care was perceived as a moral duty among the participants and was grounded in their perceived sense of responsibility. The participants' perspectives on current and future care included practical and normative considerations for meeting parental needs, and included opinions based on filial piety norms. In conclusion, this study showed that filial piety, specifically filial care, is still relevant to the younger immigrant Chinese community in the Netherlands

Forced and voluntary exercise counteract insulin resistance in rats:The role of coping style

There are large individual differences in the success rates of exercise intervention programs aimed at the prevention and treatment of obesity-related disorders. In the present study, we tested the hypothesis that differences in coping style may impact the success rates of these intervention programs. We tested insulin responses before and after voluntary wheel running in both passive (insulin resistant) Roman Low Avoidance (RLA) and proactive (insulin sensitive) Roman High Avoidance (RHA) rats using intravenous glucose tolerance tests (IVGITs). To control for a potential difference between voluntary and forced exercise, we also included RLA and RHA rats that were subjected to forced running. We found the following: 1) when given the opportunity to run voluntarily in a running wheel, passive RLA rats run more than proactively than RHA rats; 2) voluntary exercise leads to a normalization of insulin responses during an IVGTTs in RLA rats; and 3) there were no behavioral and physiological differences in efficacy between voluntary and forced running. We conclude that exercise, both forced and voluntary, is a successful lifestyle intervention for the treatment of hyperinsulinemia, especially in individuals with a passive coping style. (C) 2012 Elsevier Inc. All rights reserved