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L Zaugg

Publications and source records attributed to L Zaugg.

5 recordsLinked to original sources
PubMed1996

Total sleep deprivation and the thyroid axis: effects of sleep and waking activity.

BACKGROUND: Circadian and sleep components modulate anterior pituitary release of thyrotropin (TSH), the chemical substance regulating the thyroid hormones, thyroxine (T4), and triiodothyronine (T3). The present study examined TSH, T4, and T3 concentrations across the wake-sleep boundary time (2300-0130 hours) before, during, and after a 64-h sleep deprivation paradigm. Additionally, adrenocorticotropic hormone (ACTH) and cortisol were measured as an index of hypothalamic-pituitary-adrenal axis activation. Activity levels and ratings of effort required to perform cognitive tasks were also incorporated to evaluate physical and cognitive load, respectively, across the study period. Assessing the combined effects of activity and sleep deprivation on thyroid hormone economy is relevant to the relationship of high physical and/or cognitive performance demands during sleep deprivation inherent in extended military operations and space exploration. METHODS: There were 12 healthy subjects who were monitored during a 2-d baseline period, 3 d of total sleep deprivation, and 2 nights of recovery sleep. Serum samples were collected at 2300 hours and 0130 hours across the entire study period, and measured for TSH, T4, T3, and glucocorticoids. RESULTS: Change scores evaluated at the wake-sleep boundary time demonstrated significant inhibitory effects of sleep on thyroid hormone measures. As expected, sleep deprivation was associated with elevated TSH. However, sleep deprivation also significantly increased circulating levels of T3 at 2300 hours and T4 concentration change scores (2300-0130 hours). Glucocorticoid levels did not track thyroid hormone changes. Physical activity remained constant while subjective ratings of effort to perform cognitive tasks increased significantly during sleep deprivation. CONCLUSION: Compared to sleep deprivation studies under constant conditions reporting no change in peripheral T4 and T3 levels, the present study suggests activity level, including cognitive effort to perform, during total sleep deprivation may produce substantive changes in the thyroid axis.

Adult↗
PubMed1994

Leukocytosis and natural killer cell function parallel neurobehavioral fatigue induced by 64 hours of sleep deprivation.

The hypothesis that sleep deprivation depresses immune function was tested in 20 adults, selected on the basis of their normal blood chemistry, monitored in a laboratory for 7 d, and kept awake for 64 h. At 2200 h each day measurements were taken of total leukocytes (WBC), monocytes, granulocytes, lymphocytes, eosinophils, erythrocytes (RBC), B and T lymphocyte subsets, activated T cells, and natural killer (NK) subpopulations (CD56/CD8 dual-positive cells, CD16-positive cells, CD57-positive cells). Functional tests included NK cytotoxicity, lymphocyte stimulation with mitogens, and DNA analysis of cell cycle. Sleep loss was associated with leukocytosis and increased NK cell activity. At the maximum sleep deprivation, increases were observed in counts of WBC, granulocytes, monocytes, NK activity, and the proportion of lymphocytes in the S phase of the cell cycle. Changes in monocyte counts correlated with changes in other immune parameters. Counts of CD4, CD16, CD56, and CD57 lymphocytes declined after one night without sleep, whereas CD56 and CD57 counts increased after two nights. No changes were observed in other lymphocyte counts, in proliferative responses to mitogens, or in plasma levels of cortisol or adrenocorticotropin hormone. The physiologic leukocytosis and NK activity increases during deprivation were eliminated by recovery sleep in a manner parallel to neurobehavioral function, suggesting that the immune alterations may be associated with biological pressure for sleep.

Adult↗
PubMed1992

Immunity, major depression, and panic disorder comorbidity.

Because recent research reports indicated clinical and biological differences in major depression with and without comorbid Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R) panic disorder, and as altered immune measures were reported in selected subgroups of depressive patients, we investigated 51 pairs of major depressive episode (MDE) subjects, and gender- and age-matched healthy controls in order to determine if T lymphocytes number and function abnormalities were associated with Panic Disorder comorbidty. We found that those MDE subjects with DSM-III-R panic disorder (PD) had greater numbers of T cells (p less than 0.05) and PHA mitogen (p less than 0.05) responses than depressive patients without PD, as well as increased phytohemagglutinin (PHA) (p less than 0.05) concanavalin A (ConA) (p less than 0.02) mitogen responses compared to their controls. These data suggest that panic disorder comorbidity significantly contributes to the variance of immunologic parameters in major depression and has to be carefully assessed within psychoimmunological studies of psychiatric patients with affective disorders.

Adult↗
PubMedDate not supplied

Psychosocial and immune effects of self-hypnosis training for stress management throughout the first semester of medical school.

This study was a 19-week prospective conducted to determine the effectiveness of a self-hypnosis/relaxation intervention to relieve symptoms of psychological distress and moderate immune system reactivity to examination stress in 35 first-year medical students. Twenty-one subjects were randomly selected for training in the use of self-hypnosis as a coping skill and were encouraged to practice regularly and to maintain daily diary records related to mood, sleep, physical symptoms, and frequency of relaxation practice. An additional 14 subjects received no explicit training in stress-reduction strategies, but completed similar daily diaries. Self-report psychosocial and symptom measures, as well as blood draws, were obtained at four time points: orientation, late semester, examination period, and postsemester recovery. It was found that significant increases in stress and fatigue occurred during the examination period, paralleled by increases in counts of B lymphocytes and activated T lymphocytes, PHA-induced and PWM-induced blastogenesis, and natural killer cell (NK) cytotoxicity. No immune decreases were observed. Subjects in the self-hypnosis condition reported significantly less distress and anxiety than their nonintervention counterparts, but the two groups did not differ with respect to immune function. Nevertheless, within the self-hypnosis group, the quality of the exercises (ie, relaxation ratings) predicted both the number of NK cells and NK activity. It was concluded that stress associated with academic demands affects immune function, but immune suppression is not inevitable. Practice of self-hypnosis reduces distress, without differential immune effects. However, individual responses to the self-hypnosis intervention appear to predict immune outcomes.

Adult↗