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A Reinberg

Publications and source records attributed to A Reinberg.

220 records · Page 13Linked to original sources
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Chronoepidemiological search for circannual changes in the sexual activity of human males.

Indirect evidence of circannual (about 1-year) rhythms in the sexual activity of human males was examined utilizing the data of reported rapes in Paris, France, for 1972-78, and Houston, Texas, for 1974-75. In addition, data were available for nearly a 10-year span from Houston, Texas, as the monthly detections of the sexually transmitted diseases (STD) of syphilis and gonorrhea. The results of conventional and cosinor techniques revealed circannual rhythms in the occurrence of rape in both Paris and Houston. With regard to the former sample of 836 reported rapes, cosinor analysis revealed a circannual 0 of July 1, with the 95% CI extending from June 10 to July 20. For Houston, based upon a sample of 1,133 reported rapes, the circannual 0 occurred slightly later, around September 1, with the 95% CI extending from August 15 to September 15. Even though the overall yearly totals of reported rape differed by 4-fold between the 2 cities, the A of the circannual rhythms when expressed relative to the respective M were nearly identical, being 21.6% for Paris and 21.4% for Houston. The data on STD (3,024 cases of primary syphilis and 179,064 cases of gonorrhea), when analyzed by cosinor analysis, also revealed circannual rhythmicity. For gonorrhea, a circannual 0 of October 5, with the 95% CI from July 6 to September 4, was found; for primary syphilis the circannual 0 was somewhat delayed, occurring on November 11, with the 95% CI between October 10 and December 3. These findings, considered together with the reported observations by others of circannual rhythms in plasma testosterone and sexual activity in males as well as the sales of over-the-counter contraceptives, etc., imply that man may be regarded as a seasonal breeder, becoming more sexually active when the photoperiod becomes reduced, i.e. in the autumn. These observations provide new insight into the (chrono)epidemiology of rape and STD.

Gonorrhea↗
PubMedDate not supplied

Circadian rhythms (temperature, heart rate, vigilance, mood) of short and long sleepers: effects of sleep deprivation.

Seven long sleepers (LS) (sleep greater than or equal to 9 h) and seven short sleepers (SS) (sleep less than or equal to 7 h), aged 20 to 23 years, were selected among medical students. They measured their axillary temperature (T), heart rate (HR) and self-estimated their vigilance (V) and mood (M) every 4 h from awakening to bed time during a ten-day control span and during the two sleep deprived nights. Polygraphic sleep recordings were performed on 3 control days and recovery from 24 h (day sleep) or 36 h (night sleep) sleep deprivations. For the 4 variables (T, HR, V and M), group circadian patterns were analyzed by means of the cosinor method for the control span and after both types of sleep deprivation. The acrophases of the 4 variables clustered more in LS than in SS. The acrophases of V and M were found to be more closely related to the sleep/wake rhythm than those of T and HR. Sleep deprivation resulted in a large change of the circadian rhythms in LS but had little effect in SS as indicated by the non detection of most acrophases in LS and the persistence of such acrophases in SS. This difference might be explained by the large interindividual variability of changes induced by the sleep deprivation in LS. Moreover, day sleep recovery was more disturbed in LS than in SS.

Adult↗
PubMedDate not supplied

Advances in human chronopharmacology.

Regular and thus predictable changes in biologic susceptibility and response to a large variety of physical as well as chemical agents can now be viewed as rather common phenomena. Chronopharmacology involves both the investigation of drug effects as a function of biologic timing and the investigation of drug effects upon rhythm characteristics (the period, tau, the acrophase, phi, the amplitude, A, and the mesor, M). Illustrative examples of circadian (tau congruent to 24 hrs) chronopharmacology in man are summarized in up-dated tables, keeping in mind that the objective demonstration of chronopharmacologic facts demands the use of an appropriate methodology. Circadian changes in the effects of various chemical agents have been documented: histamine, sodium salicylate, acetylcholine, halothane, prostaglandin F2alpha, reserpine, cyproheptadine, ethanol, insulin, chlorothiazide, oxymetholone, orcinprenaline and SCH 1000 (the latter being bronchodilators), Indomethacin, lignocaine, ACTH, cortisol and various synthetic corticosteroids. Despite that pharmacological facts are well documented in man for circadian rhythms, studies are not only restricted to the 24-h period but have been already extended to rhythms of periods of e.g. approximately 30 days as well as approximately 1 year. For a better understanding of chronopharmacologic findings, three new concepts must be considered: a) the chronokinetics of a drug, defined as both rhythmic (circadian) changes in the drug bioavailability (and/or pharmacokinetic effects) and its excretion (urinary, among others); b) the chronesthesy of a biosystem to a drug, or the circadian change in the susceptibility of any biosystem to a drug (including organ systems, tumors, parasites, etc.); and c) The chronergy of a drug, or the rhythmic change in the overall effects and the effectiveness of a drug. This term takes into consideration the chronokinetics and the chronesthesies of the organismic biosystems involved. Presently, one of the aims of chronopharmacology is to solve problems of drug optimization, i.e. to enhance the desired efficiency of a corticosteroid or other medications, while reducing undesired effects. In the human organism, among other animal species, the metabolic fate of a pharmacologic agent (as well as that of a nutrient) is not constant as a function of biological time. The metabolic pathways are neither open permanently, nor open with a constant patency along the 24-h scale, among other bioperiodic domains. Thus, the chronobiologic approach concerning pharmacologic phenomena involves a lesser risk of errors and/or false information than the conventional homeostatic approach.

Biological Clocks↗