Light-emitting diodes and cool white fluorescent light similarly suppress pineal gland melatonin and maintain retinal function and morphology in the rat.

BACKGROUND AND PURPOSE: A novel light-emitting diode (LED) light source for use in animal-habitat lighting was evaluated. METHODS: The LED was evaluated by comparing its effectiveness with that of cool white fluorescent light (CWF) in suppressing pineal gland melatonin content and maintaining normal retinal physiology, as evaluated by use of electroretinography (ERG), and morphology. RESULTS: Pineal melatonin concentration was equally suppressed by LED and CWF light at five light illuminances (100, 40, 10, 1, and 0.1 lux). There were no significant differences in melatonin suppression between LED and CWF light, compared with values for unexposed controls. There were no differences in ERG a-wave implicit times and amplitudes or b-wave implicit times and amplitudes between 100-lux LED-exposed rats and 100-lux CWF-exposed rats. Results of retinal histologic examination indicated no differences in retinal thickness, rod outer segment length, and number of rod nuclei between rats exposed to 100-lux LED and 100-lux CWF for 14 days. Furthermore, in all eyes, the retinal pigmented epithelium was intact and not vacuolated, whereas rod outer segments were of normal thickness. CONCLUSION: LED light does not cause retinal damage and can suppress pineal melatonin content at intensities similar to CWF light intensities.

Effects of housing density on mouse physiology and behavior in the NASA Animal Enclosure Module simulators.

Space flight studies using the Animal Enclosure Module (AEM) make it possible to investigate the role of microgravity on animal physiology and behavior. In this study, we compared the health and well-being of mice housed at different densities in AEM simulators (AEMS), to vivarium shoebox (control) cages (VSBC). A stress assessment battery (SAB) of measures was developed to evaluate mouse health and well-being, and to determine if any of the population sizes resulted in a stressful environment. The SAB was based, in part, on recommendations of a NASA Workshop on Rodent Cage Sizing. It includes: 1) General assessment of appearance, 2) Behavioral assessment (video), 3) Food and water consumption, 4) Body weight changes, 5) Thymus, adrenal, spleen, heart and kidney weights, 6) Plasma corticosterone concentration, 7) Total plasma protein concentration, 8) Total blood leukocyte count, 9) Differential leukocyte count: neutrophil/lymphocyte ratio; eosinophil count, 10) Gastric histology.

Separation anxiety in panic disorder.

OBJECTIVE: A number of researchers have provided evidence that separation anxiety is an important antecedent or current affect in panic disorder. The objective of this pilot study was to test this hypothesis by comparing dreams, screen memories, and life situations of panic disorder patients with those of comparison patients. METHOD: A recent dream with associations, screen memories with associations, and life situations at onset of symptoms were recorded verbatim during semistructured interviews with 20 patients with DSM-III-R panic disorder and 20 comparison subjects upon referral to a private outpatient practice. A judge blind to the diagnoses rated each of the dreams, screen memories, and life situations separately on each of the 10 Gottschalk-Gleser Content Analysis Scales, thereby measuring manifest and latent death, mutilation, separation, guilt, and shame anxiety and overt and covert hostility in each group. RESULTS: mean separation anxiety scores were significantly higher in both the dreams and screen memories of the panic disorder patients than in the comparison patients. Mean scores for covert hostility directed outward were significantly higher in the dreams of the panic disorder patients than in the comparison patients. CONCLUSIONS: The hypothesis that separation anxiety is a prevalent affective undercurrent in the dreams and screen memories of panic disorder patients was supported. Significantly higher covert hostility in the panic disorder patients' dreams may support Bowlby's observation that people with high separation anxiety tend to disavow their anger.

New findings regarding light intensity and its effects as a zeitgeber in the Sprague-Dawley rat.

Circadian rhythmicities are oscillations of physiological cycles designed to create temporal organization. Circadian rhythms ensure that physiological mechanisms are expressed in proper relationship to each other and the 24 hour day. Light is the main zeitgeber ("time giver") for biological clocks. The daily variations in light intensity from dawn to dusk, and seasonally due to the rotation of the earth, act upon organisms to give them photoperiodic information. This entrainment allows them to vary biologically to prepare for reproduction, hibernation, migration and the daily adaptations necessary for survival. In most mammals, the suprachiasmatic nucleus of the anterior hypothalamus has been implicated as the central diving mechanism of circadian rhythmicity. The photic input from the retina, via the retino-hypothalamic tract, and modulation from the pineal gland help regulate the clock. In this study we investigated the effects of low light intensity on the circadian system of the Sprague-Dawley rat. A series of light intensity experiments were conducted to determine if a light level of 0.1 Lux will maintain entrained circadian rhythms of feeding, drinking, and locomotor activity.

The occupational hazards of jury duty.

Jurors on criminal trials carry a considerable burden of responsibility. They determine the defendant's fate. Additionally, during trials they can be exposed to stressful, frightening, and sordid aspects of life. The stressfulness varies depending upon the nature of the trial, its length, the nature of the testimony and evidence, the jurors' interpersonal relationships, the difficulty establishing guilt or innocence, the public's attitude, etc. These experiences can create psychological and/or physical discomfort that can be transient and mildly or moderately intense, or more serious and constitute illness. The authors have studied juries of four criminal trials--two murder cases, one child abuse case, and one obscenity case. Forty jurors were interviewed. Twenty-seven had one or more discomforting physical and/or physiological symptoms. These involved gastrointestinal distress (10 jurors); generalized nervousness (4 jurors); heart palpitation (6 jurors); headaches (4 jurors); sexual inhibitions (4 jurors); depression (4 jurors); anorexia (4 jurors); faintness (2 jurors); and numbness, lump in throat, chest pain, hives, and flu (1 juror each). Seven of the jurors became clearly ill. Illnesses included: peptic ulcer reactivation and hives, phobic reaction, anxiety state and increased alcohol use, hypertensive episode and visual scotomata, sexual inhibition, chills, fever, and depression, and post-traumatic stress disorder.

Psychiatrists' beliefs about gender-appropriate behavior.

Psychiatrists' beliefs regarding gender-appropriate behavior may influence their treatment of patients. Psychiatrists of both sexes (men: N = 76; women: N = 57) were asked to characterize optimal mental health for hypothetical female and male patients on the Bem Sex Role Inventory. The subjects' ratings for men and women were similar with two exceptions: more of the female psychiatrists rated masculine traits as optimal for female patients, and more male psychiatrists chose traits characteristic of Bem's undifferentiated category (low levels of both masculine and feminine traits) as optimal for both male and female patients. The results indicate significant changes in psychiatrists' attitudes toward gender in the past 20 years.

Buffalo Creek survivors in the second decade: stability of stress symptoms.

A follow-up study of 120 adult survivors of the Buffalo Creek dam collapse of 1972 showed group changes 14 years after the event. Decreased symptoms were noted in all areas, although significant psychopathology remained in about one-quarter of the survivors. A small group with delayed onset of symptoms was identified.

Circadian rhythms and athletic performance.

Daily or circadian rhythmical oscillations occur in several physiological and behavioral functions that contribute to athletic performance. These functions include resting levels of sensory motor, perceptual, and cognitive performance and several neuromuscular, behavioral, cardiovascular, and metabolic variables. In addition, circadian rhythms have been reported in many indices of aerobic capacity, in certain physiological variables at different exercise levels, and, in a few studies, in actual athletic performance proficiency. Circadian rhythmicity in components of athletic performance can be modulated by workload, psychological stressors, motivation, "morningness/eveningness" differences, social interaction, lighting, sleep disturbances, the "postlunch dip" phenomenon, altitude, dietary constituents, gender, and age. These rhythms can significantly influence performance depending upon the time of day at which the athletic endeavor takes place. Disturbance of circadian rhythmicity resulting from transmeridian flight across several time zones can result in fatigue, malaise, sleep disturbance, gastrointestinal problems, and performance deterioration in susceptible individuals (circadian dysrhythmia or "jet-lag"). Factors influencing the degree of impairment and duration of readaptation include direction of flight, rhythm synchronizer intensity, dietary constituents and timing of meals, and individual factors such as morningness/eveningness, personality traits, and motivation. It is the intent of the authors to increase awareness of circadian rhythmic influences upon physiology and performance and to provide a scientific data base for the human circadian system so that coaches and athletes can make reasonable decisions to reduce the negative impact of jet-lag and facilitate readaptation following transmeridian travel.

Effect of cholesterol oxidation products on cholesterol metabolism in the laying hen.

Two experiments were conducted to determine the effect of purified cholesterol and oxidized cholesterol in the diet of the laying hen on egg production characteristics, in vitro - in ovo utilization of acetate for cholesterol biosynthesis, and the activity of hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting enzyme in biosynthesis of cholesterol. Previous work has demonstrated inhibition of cholesterol synthesis by cholesterol oxides in tissue culture cells but not in hepatic tissues of animals through dietary administration. Feeding .5% of either purified or oxidized cholesterol had no effect on egg production, egg weight, body weight, or diet consumption. In both experiments egg yolk cholesterol was significantly increased by both cholesterol sources, but eggs from hens fed oxidized cholesterol had lower cholesterol contents than those from hens fed purified cholesterol. Relative utilization of acetate for cholesterol biosynthesis was significantly reduced by feeding both cholesterol sources. Hepatic enzyme activity measured by production of mevalonic acid was significantly inhibited by feeding purified cholesterol. A further significant reduction in enzyme activity was observed when oxidized cholesterol was fed, indicating that dietary cholesterol oxides are much more potent than purified cholesterol in limiting the activity of the enzyme.

A review of human physiological and performance changes associated with desynchronosis of biological rhythms.

This review discusses the effects, in the aerospace environment, of alterations in approximately 24-h periodicities (circadian rhythms) upon physiological and psychological functions and possible therapies for desynchronosis induced by such alterations. The consequences of circadian rhythm alteration resulting from shift work, transmeridian flight, or altered day lengths are known as desynchronosis, dysrhythmia, dyschrony, jet lag, or jet syndrome. Considerable attention is focused on the ability to operate jet aircraft and manned space vehicles. The importance of environmental cues, such as light-dark cycles, which influence physiological and psychological rhythms is discussed. A section on mathematical models is presented to enable selection and verification of appropriate preventive and corrective measures and to better understand the problem of dysrhythmia.

Learned illness behavior in patients with irritable bowel syndrome and peptic ulcer.

Chronic illness behavior is defined by frequent visits to physicians, multiple somatic complaints, and disability disproportionate to physical findings. The prevalence of chronic illness behavior in people with irritable bowel syndrome and peptic ulcer was studied in a telephone survey of 832 people from metropolitan Cincinnati. People with irritable bowel syndrome (8% of the sample) were more likely than people with peptic ulcer (10% of the sample), and also more likely than the general population, to have multiple somatic complaints, to view their colds and flus as more serious than those of other people, and to consult a physician for minor illnesses. People with peptic ulcer were not different from the rest of the population in these regards. Chronic illness behavior appears to be learned; people who recalled being given gifts or special foods when they had a cold or flu as a child were more likely to exhibit chronic illness behavior and also more likely to have irritable bowel syndrome. These results suggest that social learning may contribute to the etiology of irritable bowel syndrome but not peptic ulcer.

Mental health care in an adolescent medical setting.

Two hundred sixty-four troubled adolescents referred to a medical adolescent clinic were randomly assigned to one of three therapies and to one of four conditions defined by whether treatment was delayed for 6 weeks or not, and whether or not the case was presented to a psychiatrist. Patients were assessed by parents and self-reports at intake and at 6, 12, and 24 weeks, using the Adolescent Life Assessment Check List (ALAC). This 40-item instrument yielded a total and six subscores. Patients in all treatment conditions showed improvement across time as measured by the ALAC (patient or parent). Improvement was noted for each race--sex group, for each of the four conditions, and for patients assigned to each therapist. Differences in outcome were noted for immediate vs. delay groups and for groups given psychiatric consultation. By 6 months, scores on the adolescent ALAC approximated those of a matched normative sample tested. Although successful, the program should be replicated before its findings are generalized.

Bioinstrumentation for evaluation of workload in payload specialists: results of ASSESS II.

ASSESS II (Airborne Science/Spacelab Experiments System Simulation) was a cooperative NASA-ESA project which consisted of a detailed simulation of Spacelab operations using the NASA Ames Research Center CV-990 aircraft laboratory. The Medical Experiment reported on in this paper was part of the complex payload consisting of 11 different experiments. Its general purpose was to develop a technology, possibly flown on board of Spacelab, and enabling the assessment of workload through evaluating changes of circadian rhythmicity, sleep disturbances and episodical or cumulative stress. As parameters the following variables were measured: Rectal temperature, ECG, sleep-EEG and -EOG, the urinary excretion of hormones and electrolytes. The results revealed evidence that a Spacelab environment, as simulated in ASSESS II, will lead to internal dissociation of circadian rhythms, to sleep disturbances and to highly stressful working conditions. Altogether these effects will impose considerable workload upon Payload Specialists. It is suggested that an intensive pre-mission system simulation will reduce these impairments to a reasonable degree. The bioinstrumentation applied in this experiment proved to be a practical and reliable tool in assessing the objectives of the study.