Differentiation of Motor Activity of Normally Active and Hyperactive Boys in Schools: Some Preliminary Results

All non-task-related body movements during school hours were listed in 11 normally active and 12 hyperactive boys. The mean number of movements was 48 +/- 7 per 45 minutes in the normal actives and 79 +/- 16 per 45 minutes in the hyperactives. The rather monotonous increment and decrement of motor activity during the 4-hr registration period was noticed only in hyperactive boys. These results could be a consequence of a circadian rhythm, as there was independence of type of school hours and of teacher personality. The cyclical level of activity in hyperactive boys was sometimes in the range of the normal actives.     

Limitations of current medical treatments for depression: Disturbed circadian rhythms as a possible therapeutic target

The proportion of diagnosed depressives prescribed antidepressants has increased markedly over the last 20 years, mainly following the introduction of the selective serotonin reuptake inhibitors. However, currently available antidepressants have notable limitations, relating to their only moderate efficacy relative to placebo, relatively slow onset of action, possible withdrawal symptoms, and problems of compliance. Sleep disturbances are often used to identify newly presenting depressive patients, and may be part of a more general alteration of bodily rhythms. There are links between pharmacological treatments and circadian rhythms in depression, which might represent another, new option for the development of a therapeutic approach to depression treatment. Many antidepressants affect sleep, some are sedative, and others have been used specifically in severely insomniac depressives. Disturbances in circadian rhythms may be an integral part of depressive mechanisms, and normalising them via an innovative mechanism of antidepressant action may be a fruitful avenue in the search for improved antidepressant agents.     

汤岗子矿泉浴对大鼠血液皮质醇及甲状腺素日生物周期节律影响的实验观察

本文报告大鼠分别在6时、12时、18时、24时接受汤岗子矿泉38～39℃浸浴15分钟后,立即断头取血测定血液皮质醇及甲状腺素(T_4)。在6时、24时的矿泉浸浴组大鼠血浆皮质醇比对照组明显升高。在12时、18时矿泉浸浴组大鼠血清T_4比对照组明显升高。说明肾上腺皮质及甲状腺功能对全身矿泉浸浴热刺激的反应也遵循日周期节律。为矿泉治疗的时间生物学理论提供依据。     

Daily changes in presynaptic cholinergic activity of rat sympathetic superior cervical ganglion

The in vitro capacity of sympathetic superior cervical ganglia (SCG) to take up [³H]choline from the extracellular medium, to synthesize acetylcholine from [³H]choline, and to release [³H]acetylcholine in response to a high K⁺ concentration, were examined in rats throughout a 24-h cycle. Both the release of [³H]acetylcholine and the synthesis of [³H]acetylcholine from [³H]choline exhibited significant diurnal variations, showing maxima during the first half of the night. After these maxima, nocturnal acetylcholine release and synthesis decayed to daytime levels and remained low until the end of the night. [³H]Choline uptake by rat SCG did not vary significantly throughout a 24-h period. A 1.5-h exposure of rats to darkness at the 5th hour of light phase of the daily photoperiod did not change significantly any parameter studied. A 20-min, 5-Hz, electrical stimulation of the preganglionic trunk of SCG excised from rats at noon increased significantly subsequent K⁺-induced [³H]acetylcholine release but did not change [³H]acetylcholine synthesis. In decentralized SCG of rats subjected to a unilateral SCG decentralization and a contralateral sham-operation 7 days earlier, [³H]acetylcholine release and synthesis were highly reduced or abolished at the decentralized side, while [³H]choline uptake remained unaltered. The present results suggest that an activation of preganglionic rat SCG neurons takes place during the first half of the scotophase.     

Mental state,physical strength,intelligent cycle and their relationship with epilepsy

Patientsfeelimpatientbecausetheycouldnotpredicttheonsettimeofepilepsy．Ifonsettimeofepilepsycouldbepreciselypredicted，thendrugadministrationanddisabilityofpreventionwillbecomeavailable．In１８７９，Echevarrzafoundonsettimeofepilepsyisdistributedaccordingtosomerules．Inrecentyears，scientistsperformalotstudiesinvolvingcytologyandmolecularbiologyofepilepsy．Clinicaldataindicatedonsetofepilepsyhascloserelationwithbiologicalrhythmsuchasawakeandsleepcycleandmenstrualcycle．Theobjectiveofthisstudy…     

6186例脑卒中患者发病时间的季节性分析

目的探讨青岛市区脑出血(CH)、脑梗死(CI)、蛛网膜下腔出血(SAH)发病时间的季节规律。方法收集青岛市1998年～2002年脑卒中患者6186例,其中CH1179人,CI4821人,SAH186人。圆分布分析探讨脑卒中患者发病时间的季节规律。结果CH冬季高发,平均角在1月份(P<0.05),男性患者的平均角在2月份(P<0.05),女性患者的平均角在1月份(P<0.05);CI秋季高发,男、女间无差别,平均角在10月份(P<0.05);SAH秋季高发,平均角在10月份(P<0.05),男性患者的平均角在9月份(P<0.05),女性患者的平均角在10月份(P<0.05)。结论青岛市的脑卒中发病具有季节性,在脑卒中预防工作中要充分考虑其发病的季节特点,并采取相应的措施。     

Free plasma magnesium following glucose loading in healthy humans

The recognized existence of a circadian pattern in extracellular magnesium balance might mirror either an inherent rhythm in the homeostasis of this ion or dietary factors. Since in vitro insulin enhances cellular magnesium uptake, the circadian rhythm in extracellular magnesium metabolism might be modulated at least in part by carbohydrate intake. To assess this hypothesis, the effects of oral glucose loading on plasma total and ionized magnesium were investigted in lean healthy humans with a negative family history for essential hypertension and diabetes mellitus. Plasma total and ionized magnesium was similar before glucose loading and 30, 60, 90, 180, and 210 min thereafter. It is therefore concluded that in healthy humans the circadian pattern of extracellular magnesium is not modulated by the metabolic and hormonal mechanisms that adjust the concentration of glucose. Received: 5 February 1997 / Accepted in revised form: 14 April 1997     

Caffeine and light effects on nighttime melatonin and temperature levels in sleep-deprived humans

The effects of caffeine ingestion and exposure to bright light, both separately and in combination, on salivary melatonin and tympanic temperature were assessed in humans. Four treatments during a 45.5 h sleep deprivation period were compared: Dim Light-Placebo, Dim Light-Caffeine, Bright Light-Placebo and Bright-Light Caffeine. The Dim Light-Caffeine condition (200 mg twice each night) relative to the Dim Light-Placebo condition suppressed nighttime melatonin levels and attenuated the normal decrease in temperature. Combining caffeine ingestion with bright light exposure (≥2000 lux) suppressed melatonin and attenuated the normal nighttime drop in temperature to a larger degree than either condition alone; i.e. effects were additive. Circadian effects were also observed in that the amplitude and phase of the temperature rhythm were altered during treatment. These findings establish that the human melatonin system is responsive to caffeine. Other evidence suggests that caffeine may influence melatonin and temperature levels through antagonism of the neuromodulator adenosine.     

NMDA Receptor Activation Triggers Voltage Oscillations, Plateau Potentials and Burstinq in Neonatal Rat Lumbar Motoneurons ln Vitro

Whole-cell recordings of lumbar motoneurons in the intact neonatal rat spinal cord in vitro were undertaken to examine the effects of Kmethyl-D-aspartate (NMDA) receptor activation on membrane behaviour. Bath application of NMDA induced rhythmic voltage oscillations of 5.9 ± 2.1 mV (SD) at a frequency of 4.4 ± 1.5 Hz. Amplitude, but not frequency, of the voltage oscillations was membrane potential-dependent. Voltage oscillations could recruit action potentials and/or plateau potentials with or without superimposed bursting. Blockade of synaptic transmission with tetrodotoxin (TTX) sometimes resulted in a loss of oscillatory activity which could then be restored by increasing the NMDA concentration. After application of TTX, the trajectory of NMDA-induced oscillations was similar to the trajectory induced in the presence of intact synaptic networks, although the mean oscillation duration was longer and the oscillation frequency was slower (1.8 ± 1.1 Hz). Current ramps delivered after bath application of NMDA demonstrated bistable membrane properties which may underlie the plateau potentials. Injection of intracellular current pulses could initiate, entrain and terminate individual plateau potentials. The results suggest that membrane depolarization produced by oscillations may activate other intrinsic conductances which generate plateau potentials, thereby providing the neuron with enhanced voltage sensitivity, compared to that produced by NMDA receptor activation alone. These oscillatory events may have a role in the regulation of motor output in a variety of rhythmic behaviours including locomotion.