Use of dynamic two-dimensional transesophageal echocardiography for renal cell carcinoma with cavoatrial tumor thrombus

Previous investigations involving continuous blood pressure (BP) monitoring have shown an important alteration of the 24-hour BP profile in patients with obstructive sleep apnea syndrome (OSAS). We investigated the impact of REM sleep on the 24-hour BP cycle in 16 severe OSAS male patients (mean respiratory disturbance index = 66 +/- 16 events/hour of sleep), with hypertension (mean BP 162 +/- 21/105 +/- 11 mmHg World Health Organization (WHO) protocol). Two successive nights of polysomnography were performed, and arterial BP was monitored continuously during the second 24-hour period after brachial artery cannulation. During the daytime, subjects were kept awake and supine. At 3 p.m. BP was continuously monitored during quiet supine wakefulness for 20 minutes. Systolic, diastolic and mean BP and heart rate (HR) were analyzed and tabulated in mean values of 5 minute segments. Sleep/wake information were correlated with cardiovascular variables. Each uninterrupted REM sleep period was identified and comparison between the period of quiet supine wakefulness and REM sleep HR and BP values was performed. 8 OSAS patients presented a normal drop of the mean arterial BP during the nocturnal REM sleep periods compared to quiet supine wakefulness (mean value = -10.8 +/- 7.3 mmHg) ("dippers") while the other 8 subjects ("REM sleep non dippers"), revealed an elevated mean arterial BP during REM sleep (mean value = 18.9 +/- 10.9 mm Hg). The absence of the normal circadian BP dip seen during the nocturnal sleep period is considered as an indication of vascular risk. The REM sleep non dipping may play a role in this risk.     

Acute von Willebrand factor secretion from the endothelium in vivo: assessment through plasma propeptide (vWf:AgII) Levels

STUDY OBJECTIVES: Patients with coronary heart disease (CHD) and obstructive sleep apnea may have an increased cardiac risk due to nocturnal myocardial ischemia triggered by apnea-associated oxygen desaturation. Sleep structure in patients with obstructive sleep apnea is fragmented by activation of the central nervous system (CNS) (arousal) due to obstructive apneas. Nocturnal myocardial ischemia may lead to activation of the CNS as well. PATIENTS: Fourteen patients with obstructive sleep apnea and CHD disease and seven patients suffering from obstructive sleep apnea without CHD were studied. Overnight sleep studies and simultaneous six-lead ECG recordings were performed. In addition, sleep studies and ECG recordings were performed with administration of a sustained-release nitrate in these patients in a double-blinded crossover design. RESULTS: Analysis of three nights' recordings revealed 144 episodes of nocturnal myocardial ischemia in six subjects. Five patients had underlying CHD and one patient exhibited diffuse wall defects of the coronary arteries; also, 85.4% of ischemic episodes were concomitant with apneas and oxygen desaturation > 3%, and 77.8% of ischemic episodes occurred during rapid eye movement (REM) sleep, although total amount of REM sleep was only 18% of total sleep time. Mean oxygen saturation was significantly lower (p < 0.05) during apnea-associated ischemic episodes than during nonapnea-associated ischemia (77.3% vs 93.1%). Nitrate administration did not reduce ischemic episodes. Sleep architecture (macrostructure) exhibited a reduction in sleep stages non-REM 3 and 4 and REM sleep. Comparing the microstructure of sleep (arousals) within episodes with and without ischemia but similar criteria like sleep stage, apnea activity, and oxygen saturation, we found significantly more (p < 0.01) and severe (p < 0.001) arousals during periods with myocardial ischemia than during control episodes. In addition, microstructure of sleep was disturbed by myocardial ischemia itself in absence of apneas. CONCLUSION: It is concluded that patients with CHD and obstructive sleep apnea are endangered by apnea-associated ischemia and that these ischemic episodes lead to activation of the CNS and additional fragmentation of sleep. Patients with nocturnal ischemia should be screened for underlying sleep apnea even if nitrate therapy fails.     

The influence of a heavy thermal load on REM sleep in the rat

This study was carried out in order to further test the hypothesis that the occurrence of REM sleep in the rat in the form of episodes separated by long intervals (single REM sleep episodes) and by short intervals (sequential REM sleep episodes) is differently influenced by changes in both sleep and ambient related processes. Rats were studied during the exposure to Ta -10 degrees C for 24 or 48 h and during a 12 h recovery period at laboratory Ta (23 degrees C) following either the first or the second 24 h of cold exposure. The exposure to such a low Ta induced an almost complete abolition of REM sleep which was followed, during recovery, by a marked REM sleep rebound. However, in spite of the larger REM sleep deprivation, the REM sleep rebound was weaker following the 48 h-exposure than that following the exposure for 24 h. The increase in the amount of REM sleep during the recovery period was due to an increase in the amount of that occurring in the form of sequential episodes, whilst that in the form of single episodes did not change with respect to control levels. However, the occurrence of REM sleep in the form of sequential episodes was partially impaired during the REM sleep rebound observed in the recovery period following the 48 h-exposure. These results would suggest that the homeostatic regulation of physiological variables may conflict with that of REM sleep occurrence and that the degree of such a contrast is indicated, at low Ta, by the amount of REM sleep in the form of single episodes and, during the following recovery, by the amount of REM sleep in the form of sequential episodes.     

Sleep state organization in the developing piglet during exposure to different thermal stimuli

Sleep state changes in response to different thermal stimuli were investigated in newborn piglets between 2 and 10 days of age. Test animals were exposed to cold air (7-12 degrees C) and warm air (27-33 degrees C) around the face, while the remainder of the body was kept at first warm (normothermic) then hyperthermic. A separate group of animals was studied under normothermic conditions (control) for the duration of the study. Piglets showed typical changes in sleep state patterns characteristic of rapid maturation over the first 10 days of development. It was found that both the amount of rapid eye movement (REM) sleep and, in some cases, the duration of REM episodes increased in response to facial cooling regardless of rectal temperature. However, hyperthermia with warm air exposure caused a significant decrease in the amount of REM sleep but not in the duration of REM episodes. It is suggested that an infant placed to bed in a cold room or exposed to a draft might also experience a greater amount of REM sleep than an infant placed to sleep in a warm draft-free room.     

Respiratory and body movements as indicators of sleep stage and wakefulness in infants and young children

Conventional polysomnographic (PSG) sleep staging to sleep staging based on a static-charge-sensitive bed (SCSB) recording in infants and young children was compared. The study consisted of whole-night clinical sleep studies in 22 children at 24 weeks (SD 24, range 1-79 weeks) of age. Most of the children presented with respiratory disturbances during sleep. From the SCSB record, sleep stages were differentiated according to regularity of breathing, presence of body movements, and most important, presence of high-frequency components of breathing (SCSB spikes). With both methods, three sleep/wake stages were distinguished: rapid eye movement (REM) sleep, non-rapid eye movement (NREM) sleep and wakefulness. The average interscorer reliability of the PSG sleep staging controlled in nine subjects was 88%. The average concordance between the two methods ranged from 82 to 85%, depending on the criteria used for scoring the SCSB. The mean sensitivity of the SCSB to detect NREM sleep ranged from 77 to 90% and the mean sensitivity to detect REM sleep ranged from 61 to 86%. The mean positive predictive value was 89-96% for NREM sleep and 54-67% for REM sleep. In conclusion, REM sleep is characterized by irregular breathing with superimposed fast respiratory movements. These changes are specific enough to allow distinction between episodes of NREM sleep, REM sleep and wakefulness with the non-invasive SCSB method in infants and young children. Incomplete concordance between PSG and SCSB score was most frequently observed during sleep stage transition periods, where the behavioural state and electrophysiological criteria disagreed. When combined with the PSG, the SCSB provides complementary information about the behavioural state of child.     

An evaluative study of the short-term effects of once-daily, sustained-release theophylline on sleep in nocturnal asthmatics

OBJECTIVE: To examine the effects of once-daily, sustained-release theophylline on sleep patterns in nocturnal asthmatics. DESIGN: Double-blind, randomised, cross-over, placebocontrolled trial over 22 days. Seven-day period to establish therapeutic levels of theophylline (11.8 +/- 3 mg/l); 8-day cross-over period of 4 days' placebo or theophylline; 7-day baseline period. Electrophysiological sleep patterns, overnight bronchoconstriction and arterial O2 saturation monitored on nights 7, 11 and 15. SETTING: Sleep Laboratory, Medical School, University of the Witwatersrand. PATIENTS: Twelve volunteers who met the criteria for asthma, had previously used theophylline, were clinically stable and had a history of nocturnal awakenings caused by asthma were enrolled. OUTCOME MEASURES: Sleep-onset latency (SOL), within-sleep wakefulness (WSW), rapid eye movement sleep (REM), slow-wave sleep (SWS), peak expiratory flow rate (PEFR) and arterial oxygen saturation. RESULTS: SOL increased on theophylline--12 minutes (range 7-9 minutes) compared with placebo--6 minutes (range 3-11 minutes); WSW increased from 33 minutes (range 17-66 minutes) on placebo to 72 minutes (range 35-150 minutes) on theophylline. REM sleep was unaltered. SWS decreased in 10-12 patients, but this difference was not significant. Early morning PEFR was significantly better on theophylline in all study limbs. CONCLUSION: Our findings show that while once-daily, sustained-release theophylline improves bronchodilation in nocturnal asthmatics, it increases nocturnal wakefulness and decreases sleep efficiency during short-term treatment. This may, however, not be a long-term effect.     

Sleep-arousal dissociation in a case of hypersomnia

INTRODUCTION: Dissociated sleep-arousal states are clinical and experimental phenomena which represent mixed forms of the three stages of this cycle (arousal, NREM sleep and REM sleep). CLINICAL CASE: We describe the case of a man who presented with a history of excessive diurnal somnolence for the previous 5 years. He also had symptoms of sleep paralysis, hypnagogic hallucinations, automatic behavior and excessive movements during sleep. He had had no episodes of loss of muscle tone; MR was normal; HL DR2 and DQwl antigens were negative; two polisomnographic and a Multiple Latency Sleep test showed: 1. Absence of respiratory disorders. 2. Normal latency of REM sleep. 3. Periods of dissociated sleep (REM without atonia and arousal with atonia), and 4. An average sleep latency of 3.2 minutes and absence of REM periods. CONCLUSION: This case adds a new type of dissociated sleep state which may accompany the disorder known as hypersomnia without REM periods.     

Acoustic hallucinations as a symptom of a REM sleep-associated parasomnia

This 52-year-old man suffered from auditory hallucinations that occurred during brief episodes of sleep paralysis at the end of REM sleep periods. During these episodes the patient experienced a dissociated state of consciousness with REM sleep intrusions into wakefulness. The occurrence of this mixed state, and of excessive sleep-onset REM periods during daytime polysomnography (MSLT = Multiple Sleep Latency Test), point to a disorder of REM sleep generation. The existence of narcolepsy could be ruled out. The observation of REM sleep-associated hallucinations has been reported earlier. In the presented polysomnographic sleep studies the existence of a REM sleep associated parasomnia characterised by hallucinations and sleep paralysis could be confirmed.     

In vivo 1H MRS of normal breast and breast tumors using a dedicated double breast coil

OBJECTIVE: To characterize sleep patterns of patients with juvenile rheumatoid arthritis (JRA). METHODS: Sixteen patients with JRA aged 12+/-4 years and 9 controls aged 11+/-3 years underwent a comprehensive evaluation by self-report questionnaire and formal all night polysomnographic recordings. Multiple sleep latency test was performed in 7 patients. RESULTS: Patients had 90% more arousals and awakenings (p<0.01) and the median length of occurrences of uninterrupted sleep in stages 2 and 3 and rapid eye movement (REM) sleep was 60% shorter than in controls (p<0.01). The overall amount of sleep stage shift from deeper to lighter sleep was 23.5+/-10.8 events in patients compared to 14.9+/-4.0 in controls (p<0.05). In 15 of 16 patients 15% of non-REM sleep consisted of alpha-delta (alpha-rating) sleep, compared with less than 1% in controls (p<0.001). Multiple sleep latency test for patients was 10.3+/-2.6 min. There were no differences between JRA and controls in self-reported questions. However, patients reported longer afternoon naps, 1.8+/-1.3 h compared to 0.3+/-0.8 h in controls (p<0.05). CONCLUSION: Objective polysomnographic evidence of abnormal sleep has been confirmed in patients with JRA. Sleep disturbance was associated with daytime sleepiness as evidenced by abnormal multiple sleep latency test and longer afternoon naptime.     

Respiratory patterns during sleep in Down's syndrome:importance of central apnoeas

Obstructive sleep apnoea episodes have been reported repeatedly in Down's syndrome (DS) patients as a consequence of the presence of predisposing malformations or intercurrent pathology of the upper airways. There are no data on respiratory patterns of uncomplicated Down's syndrome subjects. In order to evaluate the eventual effects of central nervous system (CNS) impairment on respiration in DS, we studied the respiratory patterns during sleep of a group of 10 DS subjects, aged 8.6-32.2 y, without relevant upper airway pathology. In order to control the possible effects of sleep structure and mental retardation on the results obtained, we compared the findings in DS with those obtained from a group formed by subjects affected by fragile X syndrome (six males and one female, aged 10.0-15.42 y) another genetically determined type of mental retardation. Sleep structure was similar in both groups; however, DS subjects showed significantly higher indices of central sleep apnoea and of oxygen desaturation than fragile X patients (P < 0.005). As far as DS individuals were considered, a significant preponderance of central, as opposed to obstructive, sleep apnoeas was found (89.4% vs. 9.4%, respectively; 1.2% were mixed) which showed a significant age-related increase. Central respiratory pauses were mostly preceded by sighs, which occurred more frequently during sleep stages 1 and REM, and were often organized in long sequences of periodic-like breathing. During REM sleep, they were less frequently preceded by sighs and by body movements than during NREM sleep. Obstructive sleep apnoeas occurred more often during REM sleep and were more rarely preceded by sighs or by body movements. Both central and obstructive apnoeas induced significant oxygen desaturation in 50-69.6%. Sleep structure was not significantly modified by apnoeas and oxygen desaturation. We hypothesize that the increase in central sleep apnoeas is related to a dysfunction of the central respiratory control at a brainstem level in DS.     

Correction of acidosis in dialysis patients increases branched-chain and total essential amino acid levels in muscle

The following four issues were assessed in a group of 110 adults between the age of 20 and 59y: (1) the effect of age (regarded as a continuous variable) on polysomnographic sleep characteristics, habitual sleep-diary patterns, and subjective sleep quality; (2) the effects of age on morningness-eveningness; (3) the effects of morningness-eveningness on sleep, after controlling for the effects of age; and (4) the role of morningness-eveningness as a mediator of the age and sleep relationship. Increasing age was related to earlier habitual waketime, earlier bedtime, less time in bed and better mood and alertness at waketime. In the laboratory, increasing age was associated with less time asleep, increased number of awakenings, decreased sleep efficiency, lower percentages of slow-wave sleep (SWS) and rapid eye movement (REM) sleep, higher percentages of Stage 1 and 2, shorter REM latency and reduced REM activity and density. Increasing age was also associated with higher morningness scores. After controlling for the effects of age, morningness was associated with earlier waketime, earlier bedtime, less time in bed, better alertness at waketime, less time spent asleep, more wake in the last 2 h of sleep, decreased REM activity, less stage REM (min and percentage), more Stage 1 (min and percentage) and fewer minutes of Stage 2. For one set of variables (night time in bed, waketime, total sleep time, wake in the last 2 h of sleep and minutes of REM and REM activity), morningness-eveningness accounted for about half of the relationship between age and sleep. For another set of variables (bedtime, alertness at waketime, percentages of REM and Stage 1), morningness-eveningness accounted for the entire relationship between age and sleep. In conclusion, age and morningness were both important predictors of the habitual sleep patterns and polysomnographic sleep characteristics of people in the middle years of life (20-59 y).     

Low life purpose and high hostility are related to an attenuated decline in nocturnal blood pressure.

Objective: An attenuation of the nighttime decline in blood pressure (BP) predicts cardiovascular disease and cardiovascular-related mortality, beyond daytime BP levels. We investigated whether positive and negative psychological attributes were associated with sleep–wake BP ratios and examined sleep parameters as potential mediators of these relationships. Design: Two hundred twenty-four participants (50% men; 43% Black; mean age = 60 years) underwent ambulatory BP monitoring for 2 days and nights. Self-reports of positive and negative psychological attributes were collected. In-home polysomnography was conducted for 2 nights, and a wrist actigraph was worn for 9 nights. Main Outcome Measures: Sleep–wake mean arterial pressure (MAP) ratios. Results: After adjustment for demographics, body mass index, and hypertensive status, low life purpose and high hostility were associated with high sleep–wake MAP ratios. Depression, anxiety, and optimism were not related to MAP ratios. Sleep latency, fragmentation, architecture, and the apnea–hypopnea index were examined as potential mediators between psychological attributes and MAP ratios; only long sleep latency mediated the relationship between hostility and MAP ratios. Conclusion: Low life purpose and high hostility are associated with high sleep–wake BP ratios in Black and White adults, and these relationships are largely independent of sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sleep apnea in 81 ambulatory male patients with stable heart failure. Types and their prevalences, consequences, and presentations

BACKGROUND: Heart failure is a highly prevalent disorder that continues to be associated with repeated hospitalizations, high morbidity, and high mortality. Sleep-related breathing disorders with repetitive episodes of asphyxia may adversely affect heart function. The main aims of this study were to determine the prevalence, consequences, and differences in various sleep-related breathing disorders in ambulatory male patients with stable heart failure. METHODS AND RESULTS: This article reports the results of a prospective study of 81 of 92 eligible patients with heart failure and a left ventricular ejection fraction < 45%. There were 40 patients without (hourly rate of apnea/hypopnea, 4 +/- 4; group 1) and 41 patients with (51% of all patients; hourly rate of apnea/hypopnea, 44 +/- 19; group 2) sleep apnea. Sleep disruption and arterial oxyhemoglobin desaturation were significantly more severe and the prevalence of atrial fibrillation (22% versus 5%) and ventricular arrhythmias were greater in group 2 than in group 1. Forty percent of all patients had central sleep apnea, and 11% had obstructive sleep apnea. The latter patients had significantly greater mean body weight (112 +/- 30 versus 75 +/- 16 kg) and prevalence of habitual snoring (78% versus 28%). However, the hourly rate of episodes of apnea and hypopnea (36 +/- 10 versus 47 +/- 21), episodes of arousal (20 +/- 14 versus 23 +/- 11), and desaturation (lowest saturation, 72 +/- 11% versus 78 +/- 12%) were similar in patients with these different types of apnea. CONCLUSIONS: Fifty-one percent of male patients with stable heart failure suffer from sleep-related breathing disorders: 40% from central and 11% from obstructive sleep apnea. Both obstructive and central types of sleep apnea result in sleep disruption and arterial oxyhemoglobin desaturation. Patients with sleep apnea have a high prevalence of atrial fibrillation and ventricular arrhythmias.     

Precise measurement of individual rapid eye movements in REM sleep of humans

An automated analyzer for individual eye movements (EMs) has been developed that enables precise analyses of their incidence. Three new parameters for each EM are obtained: EM magnitude, the angle and speed of eyeball rotation, and the energy of each EM. All rapid eye movement (REM) sleep EMs from 40 nights of polysomnography for 20 healthy young men were analyzed. The mean frequency of eye movement (EM frequency) was 15.9 per minute. Compared to conventionally analyzed rapid eye movement (REM) density, EM frequency was more sensitive to differences among sleep cycles, nights, and individuals. The mean EM rotation was 6.27 +/- 0.021 degrees, the mean speed of rotation was 58.73 +/- 0.18 degrees/second, and mean energy was 525.85 +/- 3.82 degrees2/second. The distribution of changes in these new parameters differed from conventional measures across REM episodes. The conventional measures, REM episode duration, and REM density increased progressively in successive REM episodes in an ascent-to-right pattern. However, the new parameters peaked in the second, followed by relatively low values, producing an inverted V pattern. This discrepancy could indicate physiological mechanisms of EM that are not revealed in conventional measures of REM sleep intensity.     

A light microscopic and ultrastructural examination of calcified dental tissues of horses: 1. The occlusal surface and enamel thickness

Sleep is normally a time of motor quiescence. Motor disorders may, however, arise during the different phases of sleep. Nocturnal myoclonus or periodic leg movements in sleep usually occur during light sleep and may be considered the motor accompaniment of the cyclic fluctuations in excitability typical of such stages. Nocturnal frontal lobe epilepsy also occurs during NREM sleep and may be misdiagnosed as parasomnia. REM behavior disorders are instead dissociated episodes of REM sleep without atonia, often associated with or even heralding Parkinson's disease or multiple system atrophy.     

Circadian and homeostatic influences on sleep in the squirrel monkey: sleep after sleep deprivation

A series of sleep deprivation (SD) experiments were performed to examine the relative influence of circadian and homeostatic factors on the timing of sleep in squirrel monkeys free-running in constant illumination. All SDs started at the beginning of subjective night and lasted 0, 1/4, 1/2, 1, 1 1/4, or 1 1/2 circadian cycles. These six lengths represented three pairs: (0.1), (1/4, 1 1/4), (1/2, 1 1/2). Within each pair, SD ended at the same circadian phase but differed by one circadian cycle in duration. Both before and after SD, consolidated sleep (CS) episodes occurred predominantly during subjective night, even after long SDs ending at the beginning of subjective day. CS duration was strongly influenced by circadian phase but had no overall correlation with prior wake duration. Sleep loss incurred during SDs longer than 1/4 cycle was only partially recovered over the next two circadian cycles, though total sleep duration was closer to baseline levels after the second circadian cycle after SD. There was a trend toward a positive correlation between prior wake duration and the amount of NREM and delta activity measures during subjective day. Delta activity was not increased in the first 2 hours of CS after the SD. Relatively high levels of delta activity occurred immediately after the SD ended and again at the time of baseline CS onset. These data indicate that the amount of sleep and delta activity after SD in squirrel monkeys is weakly dependent on prior wake duration. Circadian factors appear to dominate homeostatic processes in determining the timing, duration and content of sleep in these diurnal primates.     

基于一维卷积神经网络的儿童睡眠分期

高质量睡眠与儿童的身体发育、认知功能、学习和注意力密切相关,由于儿童睡眠障碍的早期症状不明显,需要进行长期监测,因此急需找到一种适用于儿童睡眠监测,且能够提前预防和诊断此类疾病的方法。多导睡眠图(Polysomnography,PSG)是临床指南推荐的睡眠障碍基本检测方法,通过观察PSG各睡眠期间的变化和规律,对睡眠质量评估和睡眠障碍识别具有基础作用。本文对儿童睡眠分期进行了研究,利用多导睡眠图记录的单通道脑电信号,在Alexnet的基础上,用一维卷积代替二维卷积,提出一种1D-CNN结构,由5个卷积层、3个池化层和3个全连接层组成,并在1D-CNN中添加了批量归一化层（Batch normalization layer）,保持卷积核的大小保持不变。针对数据集少的情况,采用了重叠的方法对数据集进行了扩充。实验结果表明,该模型儿童睡眠分期的准确率为84.3%。通过北京市儿童医院的PSG数据获得的归一化混淆矩阵,可以看出,Wake、N2、N3和REM期睡眠的分类性能很好。对于N1期睡眠,存在将N1期睡眠被误分类为Wake、N2和REM期睡眠的情况,因此以后的工作应重点提升N1期睡眠的准确性。总体而言,对于基于带有睡眠阶段标记的单通道EEG的自动睡眠分期,本文提出的1D-CNN模型可以实现针对于儿童的自动睡眠分期。在未来的工作中,仍需要研究开发更适合于儿童的睡眠分期策略,在更大数据量的基础上进行实验。      

Sleep quality in Lyme disease

Complaints of chronic fatigue as well as sleep disturbances are prevalent in Lyme disease. We compared polysomnographic measures of sleep in patients with documented Lyme disease with those of a group of age-matched normal control subjects. Eleven patients meeting Centers for Disease Control criteria for late Lyme disease with serologic confirmation by enzyme-linked immunosorbent assay and Western blot without a history of other medical or psychiatric illness and 10 age-matched control subjects were studied. Lyme disease patients and controls underwent 2 nights of polysomnography. Multiple sleep latency testing (MSLT) was performed in the patients. Sleep was staged by standard criteria, and continuity of sleep was assessed for each stage of frequency analysis of consecutive epochs. All patients studied reported sleep-related complaints, including difficulty initiating sleep (27%), frequent nocturnal awakenings (27%), excessive daytime somnolence (73%) and restless legs/nocturnal leg jerking (9%). Greater sleep latency, decreased sleep efficiency and a greater arousal index were noted in Lyme patients. The median length of uninterrupted occurrences of stage 2 and stage 4 non-rapid eye movement (NREM) sleep was less in Lyme patients (6.3 +/- 3.0 epochs in patients vs. 11.4 +/- 4.4 epochs in controls for stage 2, p < 0.01, and 4.3 +/- 4.4 epochs in patients vs. 11.2 +/- 6.3 epochs in controls for stage 4, p < 0.01), indicating greater sleep fragmentation. Mean sleep onset latency during the MSLT was normal (12.7 +/- 5.6 minutes). Three patients demonstrated alpha-wave intrusion into NREM sleep. These sleep abnormalities may contribute to the fatigue and sleep complaints common in this disease.     

The development of falling asleep during the first months of life in man (author's transl)

Ten normal infants were studied at 2, 6, 12 and 20 weeks of age. EEG, respiratory rhythm, eye movements and chin EMG were recorded after the evening meal. Recording was continued during the stages of sleep. During the period of falling asleep the periods of REM sleep have been analyzed and compared with the periods of REM sleep occurring after non-REM sleep. REM sleep occurring on falling asleep and that occurring after non-REM sleep differed. Some of the following criteria were different at the earliest time of examination; absence of chin EMG activity, number of apnoeic episodes; other criteria (eye movements, respiration) differed during the first 5 months. The large number of eye movements at 2 and 6 weeks and the high respiratory rate, corresponding to that occurring during waking, could indicate that during REM sleep occurring on falling asleep, one is observing manifestations connected with the waking state.     

Sleep changes after 4 consecutive days of venlafaxine administration in normal volunteers

BACKGROUND: The purpose was to examine the effect of the antidepressant drug venlafaxine on sleep architecture and periodic leg movements of sleep (PLMS) in normal volunteers. METHOD: Eight normal volunteers were studied under laboratory sleep conditions as follows: 1 acclimatization night, 1 baseline night, and 4 consecutive nights of venlafaxine p.o. administration (75 mg during the first 2 nights and 150 mg the last 2 nights). RESULTS: Venlafaxine increased both wake time and sleep stage I. Sleep stages II and III were reduced. REM sleep time was reduced after the first venlafaxine dose, and, by the fourth night, REM sleep was completely suppressed in all volunteers. Six of the eight volunteers showed PLMS at a frequency above 25 per hour. CONCLUSION: Venlafaxine produces several sleep disturbances, which include abnormal leg movements.