Scalp topography of the spontaneous K-complex and of delta-waves in human sleep

Objective: Together with spindles, K-complexes are well known hallmarks of stage 2 sleep (S2). However, little is known about their topographical distribution in comparison to delta-waves and to K-complexes superimposed by spindles. Patients and methods: In this study, the topographical distribution of spontaneous K-complexes and delta-waves in S2 and delta-waves in stage 4 sleep (S4) in 10 healthy young adults (aged 20 to 35 years, 7 female) was investigated. K-complexes with and without spindles in S2, delta-waves with and without spindles in S2, and delta-waves in S4 distributed all over the night were visually selected. EEG power maps and statistical parametric maps were calculated. Results: Absolute delta power of S2 K-complexes appeared to be significantly higher than of S2 delta-waves and delta power of S4 delta-waves was higher than of S2 delta-waves. In K-complexes and delta-waves, power was found to be highest over medio-frontal regions in the delta frequency band (0.5 - 4.0 Hz) with a second maximum occipitally in delta-waves, no matter whether superimposed by a spindle or not. Conclusion: K-complexes and delta-waves in S2 differ in topographical distribution. Even though in S2 delta-waves have less power, they have a similar topographical distribution in S2 and S4, supporting the hypothesis that delta-waves in S2 further develop towards delta-waves in slow wave sleep. The delta frequency components of K-complexes and delta-waves are unaffected by spindles.     

Proportional Jerk: A New Measure of Motion as Applied to Eye Movements in Sleep and Waking

The third derivative of motion or the change in the rate of acceleration (also known as jerk) is examined in terms of its applicability to the study of psychophysiological function. An algorithm of this third derivative is presented to show that jerk can be derived from the arithmetic difference of two slopes which constitute the portion of motion being differentiated. By modifying the algorithm, a new parameter termed “proportional jerk’ or PJ is formulated whereby one slope is measured relative to the other slope; this PJ provides information about the smoothness of movement without being influenced by the velocity as is the traditional jerk measure. A practical application of the PJ to waking saccades and REMs in 11 human subjects revealed that REMs are significantly “jerkier’ or less smooth than waking calibration eye movements. Whereas the waking eye movements had a well-defined negative phase of the PJ, the REMs did not show such stereotypical behavior. This is in accord with previous work which showed that waking saccade velocity increases to a maximum and then decreases whereas REMs maintain their peak or near peak velocities for varying periods. It was suggested that PJ can be useful in detecting subtle temporal changes in the course of movements and may be used as a parameter of motion even when the absolute amplitude is unknown.     

Facial Muscle Tonus During REM and NREM Sleep

Equipment and procedures were devised for quantifying relatively noise-free recordings of low amplitude chin and lip electromyograms (EMGs) during sleep. A total of 28 REM periods were recorded from 5 young adult female Ss. Tonic EMG levels tended to decline toward their lowest level of the night beginning 5 min in advance of REM periods. With very rare exceptions, the lowest EMG levels of the night were maintained throughout REM sleep. During the 20 min of NREM sleep which followed REM periods, mean EMG levels increased over the REM levels but were lower than those recorded during the 20 min of NREM sleep which preceded the REM periods. This pattern of tonic EMG variation obtained for each of the first 3 REM periods of the night.     

急性冠脉综合症与补体激活

目的： 评价各种类型急性冠脉综合症 (ACS) 病人补体激活的情况和补体激活与心肌损伤的关系。方法： 研究对象分为ACS组110例和正常对照组18人。 ACS组包括ST段抬高型心肌梗死（STEMI）51例，非ST段抬高型心肌梗死（NSTEMI）28例和不稳定性心绞痛（UA）31人。检测病人和正常对照健康人血浆C₃和C₄，CK-MB和肌钙蛋白T (TnT)浓度。结果： STEMI和 NSTEMI病人峰值C₃ 水平［分别为（1 525±302） mg/L和（1 516±289）mg/L］ 和C₄［分别为（423±123） mg/L和（396±68） mg/L］水平高于UA病人和对照组的C₃［分别为（1 275±172） mg/L和（1 072±196） mg/L,P<0.01］ 和C₄［分别为（356±91）mg/L和（182±73） mg/L,P<0.01］。UA病人的 C₃ ［(1 275±172） mg/L］和C₄ ［（356±91） mg/L］均高于对照组（P<0.01）。 ACS病人C₃和C₄水平在住院的前7 d均有明显的变化（P<0.01）。ACS病人峰值C₃和C₄水平与峰值CK-MB（分别为r=0.51和r=0.46，P<0.01）和肌钙蛋白T（分别为r=0.48和r=0.39，P<0.01）呈正相关。结论： ACS病人血浆C₃和C₄均明显升高。C₃和C₄水平与ACS的联系提示补体激活与心肌坏死有关。     

QUANTIFICATION OF THE REM SLEEP CYCLE AS A RHYTHM

The goal of this study was to develop an objective quantitative method for representing the temporal organization of sleep in terms of the period and rhythmicity of REM sleep occurrences. Data on normative human sleep, already scored for stage REM and not stage REM, were subjected to a “binary autocorrelation.” The mean period over 92 nights of sleep for 10 Ss was 101.5 min and quite stable. Data is also presented on variability of the rhythm in terms of an “index of rhythmicity.” Measures of temporal organization may prove to be as significant for sleep research as amount of the various sleep stages.     

基诺族睡眠状况调查及分析

目的:了解基诺族睡眠的一些基本情况、失眠症的发生率和治疗情况.方法:使用自拟的"基诺族睡眠情况调查表",通过入户调查和现场访谈对126名基诺族人进行调查.结果:随年龄增长基诺族人的睡眠时间渐减少.<30岁年龄组有午睡习惯的比例高于30岁以上年龄组,差异有统计学显著性.34.12%(43人)符合失眠症诊断,失眠原因以各种精神疾病(41.86%)和酒依赖(30.23%)最为常见.失眠患者中, 就诊率为25.58% (11例).结论:基诺族睡眠的基本情况与国内其他人群相比有一些共同之处;失眠发生率较高,但由于本研究样本量和样本选择的不足,此结果还需进一步证实.     

All night spectral analysis of EEG sleep in young adult and middle-aged male subjects

The sleep EEGs of 9 young adult males (age 20–28 years) and 8 middle-aged males (42–56 years) were analyzed by visual scoring and spectral analysis. In the middle-aged subjects power density in the delta, theta and sigma frequencies were attenuated as compared to the young subjects. In both age groups power density in the delta and theta frequencies declined from NREM period 1 to 3. In the sigma frequencies, however, no systematic changes in power density were observed over the sleep episode. In both age groups the decay of EEG power (0.75–7.0 Hz) over successive NREM-REM cycles and the time course of EEG power during NREM sleep was analyzed. The decay rate of both EEG power density over successive NREM-REM cycles and EEG power density during NREM sleep was smaller in the middle-aged subjects than in the young subjects. It is concluded that the age-related differences in human sleep EEG power spectra are not identical to the changes in EEG power spectra observed in the course of the sleep episode. Therefore age-related differences in EEG power spectra cannot be completely explained by assuming a reduced need for sleep in older subjects. The smaller decay rate of EEG power during NREM sleep in the middle-aged subjects is interpreted as a reduced sleep efficiency. The results are discussed in the frame work of the two-process model of sleep regulation.     

Sleep apnea-related cognitive deficits and intelligence: an implication of cognitive reserve theory

Cognitive deficits in patients with obstructive sleep apnea syndrome (OSAS) are well demonstrated, but the pathophysiology of these deficits is still controversial, as the relationship between OSA severity and cognitive deficits is usually weak. Our study considers the possible relationship between OSA-related cognitive deficits and the overall intellectual function of OSA patients. Forty-seven OSA patients and 36 normal individuals underwent a neuropsychological battery test assessing attention and alertness. According to the resulting IQ score, patients and controls were divided into a high-intelligence group (IQ > or = 90th percentile) and a normal-intelligence group (50 < or = IQ < 90%ile). Between the two patient groups there were no significant differences noticed, regarding OSA severity or sleepiness. High-intelligence patients showed the same attention/alertness performance compared with the high-intelligence controls. On the contrary, patients with normal-intelligence showed attention/alertness decline compared with the normal-intelligence control group. The two patient groups were re-examined with the same battery test after at least 1 year of CPAP treatment. At re-examination neither patient group showed any differences regarding attention and alertness compared with the control groups. We assume that high-intelligence may have a protective effect against OSA-related cognitive decline, perhaps due to increased cognitive reserve.     

Short rib-polydactyly syndrome and pericentric inversion of chromosome 4

We report on a newborn infant with clinical and radiological manifestations of some type of short rib-polydactyly syndrome who died soon after birth. Chromosomal studies on peripheral blood lymphocytes and chondrocytes demonstrated an apparently balanced pericentric inversion of chromosome 4 (present in the mother also). This association may have occurred by chance but, if not, the chromosomal breakpoints could interrupt the gene responsible for short rib-polydactyly syndromes, or else be related to the mechanism of short rib-polydactyly syndromes. © 1994 Wiley-Liss, Inc.