Disorders of the circadian sleep-wake rhythm--diagnostic and therapeutic principles

The most important circadian rhythm disorders are presented excluding jet lag syndrome and shift work. Clinical and psychological findings, pathophysiological principles and social consequences are discussed with reference to recent literature. The ICSD classification is reviewed critically and proposals for operationalisation of new diagnostic procedures are offered. The current therapeutic principles are described and it is attempted to develop a more systematic documentation of therapy aiming at the possibility of future outcome-comparison between the presently very heterogenic principles.     

Hippocampal interneuron activity in unanesthetized rats: relationship to the sleep-wake cycle

Evoked population spikes and interneuronal discharges were recorded throughout the sleep-wake cycle in hippocampal regions CA1 and dentate gyrus (DG) of ten chronically implanted rats. During quiet wakefulness (QW) and slow-wave-sleep (SWS) (non-theta rhythm states), the primary shock of paired stimuli evoked in CA1 both high amplitude population spikes and multiple interneuron discharges when compared to active wakefulness (AW) and rapid-eye-movement (REM) sleep (theta rhythm states). A second shock was delivered to CA1 afferents 60 ms after the first shock. This second shock evoked a small population spikes during non-theta states, whereas it evoked higher amplitude population spikes in theta states. The second shock also evoked unit interneuron discharges in non-theta states but not in theta states. In the dentate gyrus, identical primary afferent stimulation evoked similar interneuron activity and uniform amplitude population spikes throughout the sleep-wake cycle. In contrast, the secondary shocks evoked a striking potentiation of the field population spike during sleep, SWS and REM sleep compared to AW and OW. Evoked DG interneuron spikes following the second population spike were greater in number during SWS compared to the other stages. Our findings suggest that hippocampal field potentials and interneuron activity recorded in vivo are regionally regulated, have unique state-dependent expression and are strongly influenced by inhibitory feed-forward mechanisms.     

Acutely shifting the sleep-wake cycle: nighttime sleepiness after diurnal administration of temazepam or placebo

HYPOTHESIS: Sleepiness on the job is a common problem suffered by people involved in night shift work, especially in conditions of abrupt reversal of the sleep-wake cycle, such as emergencies and combat air operations. It is well known that sleepiness can severely affect alertness and performance. One of the most useful countermeasures is to take a prophylactic nap before working at irregular hours. To induce and maintain sleep in the "forbidden zones for sleep" during the day, it is possible to use suitable benzodiazepine hypnotics such as temazepam (TMZ). However, it is then necessary to monitor sleepiness and performance the night following the diurnal intake of the drug in order to evaluate possible side effects. METHODS: In this study, sleepiness was subjectively and objectively measured during the night after a daytime administration of TMZ 20 mg in soft gelatine capsules or placebo to obtain a prophylactic sleep. RESULTS AND DISCUSSION: Results showed the effectiveness of TMZ for inducing and maintaining diurnal sleep. This lengthening of total sleep time did not cause a decrease of sleepiness during the night, but no significant carry over effect of TMZ was present for nighttime sleep tendency. Both polygraphic and subjective measures of sleep latency decreased during the night. Finally, no significant relationship between the Stanford Sleepiness Scale and the Multiple Sleep Latency Test measures was found.     

5-Hydroxyindoles compounds and nitric oxide voltammetric detection in the rat brain: changes occurring throughout the sleep-wake cycle

The release of serotonin may occur throughout the sleep-wake cycle according to 2 different modalities: - by the axonal nerve endings during waking; - by the dendrites and/or the soma of the nucleus raphe dorsalis (nRD) during sleep. Neuronal nitric oxide (NO), synthesised by constitutive NO synthase (NOS), is colocalized with neurotransmitters such as GABA, acetylcholine, somatostatin, serotonin, etc. In order to evaluate its modalities of release throughout the rat sleep-wake cycle, a sensor allowing its specific detection in freely moving animals was prepared. In the cortex, the highest NO signal occurs during the waking state (W=100%) versus slow wave sleep (SWS=-6%) and paradoxical sleep (PS=-9%). The mild variations observed might reflect a mean of the individual sleep-wake cycle variations attached to each NO source (GABAergic interneurons, cholinergic and serotoninergic axonal nerve endings, etc.).     

Cardiovascular responses to treadmill and cycle ergometer exercise in children and adults

This study was conducted to determine whether submaximal cardiovascular responses at a given rate of work are different in children and adults, and, if different, what mechanisms are involved and whether the differences are exercise-modality dependent. A total of 24 children, 7 to 9 yr old, and 24 adults, 18 to 26 yr old (12 males and 12 females in each group), participated in both submaximal and maximal exercise tests on both the treadmill and cycle ergometer. With the use of regression analysis, it was determined that cardiac output (Q) was significantly lower (P 相似文献   

Twenty-four-hour sleep-wake patterns in a nursing home population.

Sleep-activity patterns were objectively recorded over a 24-hr period in 19 elderly nursing home residents. On average, both sleep and wake times were observed during every hour of the 24 recorded hours; however, the sleep pattern of the residents was fragmented so that they rarely experienced even a single hour of consolidated time spent sleeping. It is hypothesized that several independent factors, including compensation for lost sleep, increased total time in bed, weakening of social constraints, and deterioration of the circadian sleep–wake rhythm, are interacting to produce this increase in sleep fragmentation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Validity of sleep log compared with actigraphic sleep-wake state

OBJECTIVE: To evaluate the efficacy and complications of external cephalic version in term (37 or more weeks) gestation. STUDY DESIGN: A case series from February 1990 until December 1994 studied 160 patients with term singleton breech presentation. External cephalic version (ECV) with prophylactic tocolysis was the method used. RESULTS: ECV was successful in 67% of the cases (107/160) overall, in 56% of the nulliparous (57/102) and 86% of the multiparous women (50/58). About 90% of those with successful ECV (96/107) had a vaginal delivery with a vertex presentation of the fetus. Emergency Caesarean section due to fetal distress was not required during or immediately after the procedure. No perinatal mortality or babies with an Apgar score less than 7 at 5 min were observed. CONCLUSIONS: ECV in term pregnancy seems to be useful and it is safe both for the mother and the fetus. It should be performed at term, with close monitoring of the fetus, and in an environment able to provide an emergency Caesarean section.     

Disorders of the mitochondria

Recent advances in our understanding of the structure and function of mitochondria have led to the recognition that inherited and acquired mitochondrial dysfunction may be responsible for diseases affecting the liver and other organ systems. Mitochondrial health may also determine hepatocyte survival in other hepatic disorders not directly related to the mitochondrion. Primary mitochondrial hepatopathies are conditions in which there are inherited defects in structure or function of the mitochondria, most of which involve the respiratory chain and oxidative phosphorylation, fatty acid oxidation, the urea cycle, and other pathways confined to mitochondria. Maternally inherited mutations or deletions of the mitochondrial genome, or putative nuclear gene mutations encoding electron transport proteins, cause defective electron transport, oxidative stress, impaired oxidative phosphorylation, and other metabolic derangements that lead to hepatic failure or chronic liver dysfunction in affected children. The mitochondrial DNA (mtDNA) depletion syndrome, which similarly leads to liver failure and neurologic abnormalities, is caused by a putative nuclear gene that controls mtDNA replication or stability. Other proven or suspected primary mitochondrial hepatopathies include Pearson's marrow-pancreas syndrome, Alpers disease, mitochondrial neurogastrointestinal encephalomyopathy syndrome, and Navajo neuropathy. Secondary mitochondrial hepatopathies are conditions in which the mitochondria are major targets during liver injury from another cause, such as metal overload, certain drugs and toxins, alcoholic liver injury, and conditions of oxidant stress. Diagnosis of mitochondrial dysfunction may be difficult with currently available tools, however, elevated blood lactate: pyruvate ratios or arterial ketone body ratios with characteristic liver histology are initial tests. Measuring respiratory chain enzyme activities, mtDNA levels, and searching for mtDNA mutations and deletions are more specific tests. Treatment of these disorders is currently empirical, involving agents that may improve the redox status of mitochondria, promote electron flow, or act as mitochondrial antioxidants. Liver transplantation has occasionally been successful in patients who lack other systemic involvement.     

Associations in the Course of Personality Disorders and Axis I Disorders Over Time.

In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of passive-avoidance training on sleep-wake state-specific activity in the basolateral and central nuclei of the amygdala.

This study examined the effects of intense emotional learning on the sleep-wake state-specific electroencephalographic (EEG) activities of the basolateral (BLA) and central (CeA) nuclei of the amygdala. Rats were trained on a passive-avoidance learning (PAL) protocol that was followed by 6 hrs of undisturbed polygraphic recording and a PAL test. After PAL training, the total amount of REM sleep decreased; high-frequency EEG power decreased in the CeA during REM sleep and increased in the BLA during all sleep-wake stages. These results suggest that there is no homeostatic demand for REM sleep after intense emotional learning. However, the PAL-specific changes in the local EEG suggest that some form of memory processing may occur within the amygdala during REM sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Disorders of the calcium-sensing receptor

From 1990 to 1995, 12 patients with cavo-atrial renal cell carcinoma underwent resection of the tumor. Circulatory arrest was employed in 11/12 cases. The neoplasm extended to the inferior vena cava in two patients and to the intrahepatic veins or right atrium in five cases. Two severely cardiac compromised patients died perioperatively. Of five patients who showed preoperative suspicion of isolated metastases, 3 patients died postoperatively because of relapsing disease after a mean period of 10.8 months. Five patients are alive and doing well after a mean follow-up of 14.8 months. In our experience myocardial dysfunction determined poor immediate survival. Mid-term survival was influenced by preoperative metastases and lymph-node involvement, but not by intracaval extension. Circulatory arrest appears to be a relatively safe technique to remove renal carcinoma with cavo-atrial extension and should be indicated whenever there are no metastases.     

Those who broke the cycle: Therapy with nonabusive adults who were physically abused as children.

Based on observations of 10 nonabusive adults who were physically abused as children, it is contended that these Ss differ from abusive adults who were abused as children in significant ways. It is recommended that abused children receive intensive therapy either at the time that the abuse is discovered or at a developmentally more appropriate stage to block persistence of symptoms into adulthood. It is suggested that these nonabusive adults present a constellation of symptoms that may not be recognized as posttraumatic stress syndrome. For both the abused child and the adult a highly interactive course of therapy is recommended, during which the major goal is reparenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Disorders of the reticular activating system

The organization of components of the reticular activating system and their role in sleep-wake mechanisms and arousal are described. A functional model is proposed based on known neuroanatomical and neurophysiological findings. The involvement of these elements of the reticular activating system in various neurological and psychiatric disorders is discussed. A series of hypotheses are advanced to account for the role of these nuclei in such diverse disorders as schizophrenia, post-traumatic stress disorder, REM behavior disorder, Parkinson's disease and narcolepsy. This line of reasoning suggests that, when neurological or psychiatric disorders manifest symptoms related to arousal and sleep-wake control, disturbances of elements of the reticular activating system must be considered responsible.     

Disorders of the integrative brain functions in posttraumatic hydrocephalus

As many as 110 patients with posttraumatic hydrocephalus in the remote period of mild closed craniocerebral injury underwent routine neuropsychologic evaluation. 80.9% of the patients presented with disorders of higher integrative functions of the brain; of these, 72.7% appeared to get too easily fatigued, their mental processes running to exhaustion too soon. In decreasing rank order are disorders of attention, slowing down of those processes relating to abstract thought, power of apprehension and recent memory (62.7%, 60.9%, and 34.5% respectively). Mnestic disturbances prevailed among patients with moderate severity posttraumatic hydrocephalus (40%) and external hydrocephalus (47.8%). Mild degree hydrocephalus was free from disturbances to higher integrative functions of the brain. The aforesaid attests to the need of the nootropic, vasoactive agents, drugs having resolving and dehydrating effects to be included into the combined treatment of the above patient population.