A rat model of preeclampsia

Preeclampsia/eclampsia is a disorder of human pregnancy that continues to exact significant maternal morbidity and mortality and fetal wastage. Therapy of these disorders has not changed in over 50 years and there are no proven preventive measures. We describe a model of the development of a syndrome in the pregnant rat that resembles preeclampsia, which results from the imposition of excessive volume expansion early in gestation. We administered desoxycorticosterone acetate (DOCA) to pregnant animals whose drinking water had been replaced with saline. We compared the results obtained in these animals with those resulting from the study of control, virgin animals, virgin animals receiving DOCA and saline, and normal pregnant (NP) animals. The virgin animals given DOCA and saline did not become hypertensive. The experimental paradigm in the DOCA plus saline pregnant (PDS) animals provides many of the phenotypic characteristics of the human disorder including the development of hypertension, proteinuria, and intrauterine growth restriction. In addition, the mean blood nitrite/nitrate concentration was reduced in the PDS rats compared with their NP counterparts. We propose that this model may prove to be useful in the study of the human condition.     

Excessive daytime sleepiness in young adults: a 20-year prospective community study

OBJECTIVE: Excessive daytime sleepiness (EDS) is a symptom with high clinical and public health importance because of its association with increased risk for accidents, decreased productivity, and impaired quality of life. Little information is available regarding the longitudinal course or clinical correlates of EDS. The aim of this study was to explore associations between self-reported EDS, sleep disorder symptoms, major depression, and anxiety in a longitudinal community study of young adults. METHOD: A prospective single-age community study of young adults (Zurich Cohort Study) was conducted from 1978 through 1999. Information was derived from 6 interviews administered when participants (N = 591) were ages 20, 22, 27, 29, 34, and 40 years. Trained health professionals administered a semistructured interview for health habits and psychiatric and medical conditions. The presence of either or both of 2 symptoms-accidentally falling asleep or excessive need for sleep during the day-was used to establish the presence of EDS. RESULTS: EDS was a common complaint among the study participants, with increasing prevalence with age. Cross-sectionally, EDS was associated with insomnia symptoms, nocturnal hypersomnia, anxiety disorders, somatization, and reduced quality of life. Longitudinally, impaired sleep quality, waking up too early, and anxiety were associated with later EDS. Conversely, EDS was not significantly associated with later anxiety or depressive disorders. CONCLUSIONS: Insomnia symptoms and anxiety are associated with the subsequent occurrence of EDS. Although these findings do not demonstrate causality, insomnia and anxiety disorders are prevalent and treatable conditions, and our results may have important clinical implications for the prevention and treatment of EDS. Whether the results of this study are limited to populations with elevated levels of psychopathology remains to be tested.     

Photostimulator allowing independent control of rods and the three cone types

This report describes a second-generation photostimulator with four primary lights that allows independent control of the stimulation of the four receptor types in the human eye. The new design uses LEDs (with light levels controlled by eight drivers that include voltage-to-frequency converters that provide 1-micros pulses at frequencies up to 250 kHz), with four center channels being combined by use of a fiber optic assembly, and likewise for four surround channels. Four fiber optic bundles are merged into a single bundle whose output is fed into a spatial homogenizer terminated by a diffuser. An interference filter is sandwiched between each LED and the fiber optic bundle. Two camera lenses collimate light from the diffusers, one for center and one for surround. The center-surround field configuration is formed by a photometric cube with a mirrored ellipse on the hypotenuse. A field lens places images of the diffusers in the plane of an artificial pupil. The fields are highly uniform. Following alignment and calibration, the center and surround fields are indistinguishable. An observer calibration procedure, designed to compensate for prereceptoral filtering, is shown by calculation to correct also for normal observer receptoral spectral sensitivity variation. With the instrument calibrated for the individual observer, a peripherally fixated 200-ms 40% contrast rod center field pulse, highly conspicuous under dark adaptation, is invisible following light adaptation.     

Obsessive-compulsive severity spectrum in the community: prevalence,comorbidity, and course

OBJECTIVES: To describe lifetime prevalence rates, course and comorbidity of obsessive-compulsive disorder (OCD), obsessive-compulsive syndromes (OCS) and OC-symptoms (OC-sx) up to age 41. METHODS: In the Zurich community cohort study 591 subjects were selected after screening at the age of 19 and studied prospectively by 6 interviews from 20 to 40; they represent 1599 subjects of the normal population. The diagnoses of OCD met DSM-IV criteria.Course was assessed by graphic illustrations and prospective data. RESULTS: The lifetime prevalence rate was 3.5 % for OCD (males 1.7%, females 5.4 %) and 8.7 % for OCS (males 9.9%, females 7.5 %). The onset of OC-sx was 18 years (median); and in 70% before age 20. OCD was treated in one third of cases, OCS in 6.1%. The course of symptoms was chronic in 60%,but OCD and OCS showed in most cases considerable improvements over time. OCD reduced quality of life mostly in the subject's psychological wellbeing and at work but to a considerable extent also in other social roles. Comorbidity was prominent with bipolar disorder, panic disorder and social phobia and also significant with bulimia, binge eating, generalized anxiety disorder and suicide attempts; there was no association with substance abuse/dependence. CONCLUSION: OCD and OCD are manifestations of a wide spectrum of severity with high prevalence and strong clinical validity. The long-term course is better than generally assumed.