No abstract

Monthly rates of admission of manic patients to the Department of Psychiatry in Galway Regional Hospital were examined for a five-year period. Monthly variation in admission rates was compared with monthly levels of sunshine, temperature and daylength. Results indicated a significant seasonal variation in the prevalence of mania: admission rates were higher in the sunnier months and in months with a greater average daylength. It is suggested that the presentation of mania in this fashion is due to an abnormal response to light in these patients.

Changing body posture causes rapid and consistent alterations in plasma [NO]. Researchers should therefore carefully consider the effect of posture when measuring this variable.

PurposeThe present study investigated different doses of ultraviolet-A (UV-A) light on plasma nitric oxide metabolites and cardiorespiratory variables.MethodsTen healthy male participants completed three experimental conditions, 7 days apart. Participants were exposed to no light (CON); 10 J cm2 (15 min) of UV-A light (UVA10) and 20 J cm2 (30 min) of UV-A light (UVA20) in a randomized order. Plasma nitrite [NO2−] and nitrate [NO3−] concentrations, blood pressure (BP), and heart rate (HR) were recorded before, immediately after exposure and 30 min post-exposure. Whole body oxygen utilization (), resting metabolic rate (RMR) and skin temperature were recorded continuously.ResultsNone of the measured parameters changed significantly during CON (all P > 0.05). and RMR were significantly reduced immediately after UVA10 (P < 0.05) despite no change in plasma [NO2−] (P > 0.05). Immediately after exposure to UVA20, plasma [NO2−] was higher (P = 0.014) and and RMR tended to be lower compared to baseline (P = 0.06). There were no differences in [NO2−] or at the 30 min time point in any condition. UV-A exposure did not alter systolic BP, diastolic BP or MAP (all P > 0.05). UV-A light did not alter plasma [NO3−] at any time point (all P > 0.05).ConclusionsThis study demonstrates that a UV-A dose of 20 J cm2 is necessary to increase plasma [NO2−] although a smaller dose is capable of reducing and RMR at rest. Exposure to UV-A did not significantly reduce BP in this cohort of healthy adults. These data suggest that exposure to sunlight has a meaningful acute impact on metabolic function.

No abstract

No abstract