激光生物效应及医学应用研究

激光作用于生物体会产生物理、化学或生物学的效应,激光正是通过这些效应达到医学基础研究、诊断和治疗疾病的目的.本文简介了激光与生物组织相互作用所产生的生物效应,概述了激光生物效应在生物学和医学研究中的应用.     

The effects of breathing-related sleep disorders on mood disturbances in the general population

BACKGROUND: Results of clinical studies suggest that there may be a relationship between breathing-related sleep disorders and depressive disorders. This study aims to assess the impact of breathing-related sleep disorder on major depressive disorder in the general population. METHOD: A cross-sectional telephone survey was carried out between 1994 and 1999 in the general population of the United Kingdom, Germany, Italy, Portugal, and Spain. A total of 18,980 randomly selected subjects aged 15 to 100 years and representative of the general population of their respective countries participated in the study. The questionnaire included a series of questions about sleep quality, breathing-related sleep disorder symptoms, mental disorders, and medical conditions. Data are presented using point prevalence. RESULTS: 2.1% of the subjects were found with obstructive sleep apnea syndrome at the time of the interview, and 2.5% had some other type of DSM-IV breathing-related sleep disorder diagnosis. The association of DSM-IV breathing-related sleep disorder diagnosis and major depressive disorder diagnosis was found in 0.8% of the sample. As many as 18% of individuals with a major depressive disorder diagnosis also have a DSM-IV breathing-related sleep disorders diagnosis, and 17.6% of subjects with a DSM-IV breathing-related sleep disorders diagnosis have a major depressive disorder diagnosis. Multivariate models showed that even after controlling for obesity and hypertension, the odds of having a DSM-IV breathing-related sleep disorders diagnosis was 5.26 for individuals with a major depressive disorder diagnosis. CONCLUSION: About 800 of 100,000 individuals have both a breathing-related sleep disorder and a major depressive disorder. The identification of 1 of these 2 disorders should prompt the investigation of the other disorder since nearly a fifth of them have the other disorder.     

Prevalence and consequences of sleep disorders in a shift worker population

INTRODUCTION: Irregular work schedules often results in a disruption of the normal circadian rhythm that can causes sleepiness when wakefulness is required and insomnia during the main sleep episode. METHOD: Two physicians using the Sleep-EVAL system interviewed 817 staff members of a psychiatric hospital. The interviews were done during the working hours. In addition to a series of questions to evaluate sleep and mental disorders, the evaluation included a standard questionnaire assessing work conditions, work schedule and their consequences. Three work schedules were assessed: (1) fixed daytime schedule (n=442), (2) rotating daytime shifts (n=323) and (3) shift or nighttime work (n=52). RESULTS: Subjects working on rotating daytime shifts were younger than the two other groups and had a higher proportion of women. Participants working on rotating daytime shifts reported more frequently than the fixed daytime schedule workers to have difficulty initiating sleep (20.1% vs. 12.0%). The sleep duration of shift or nighttime workers was shorter than that of the two other groups. Furthermore, subjects working rotating daytime schedule reported to have shorter sleep duration of about 20 min when they are assigned to the morning shift. Work-related accidents were two times more frequent among the rotating daytime workers (19.5%) compared with the fixed daytime schedule workers (8.8%) and the group of nighttime or shift workers (9.6%). Sick leaves in the previous 12 months were also more frequently reported in the rotating daytime schedule group (62.8%) as compared with the daytime group (38.5%, P<.001); 51.9% of nighttime or shift workers took sick leave. CONCLUSIONS: Working on a rotating daytime shifts causes significant sleep disturbances. As consequences, these workers are more likely to feel sleepy at work and are more likely to have work-related accidents and sick leaves.     

Prevalence of narcolepsy symptomatology and diagnosis in the European general population

OBJECTIVE: To determine the prevalence of narcolepsy in the general population of five European countries (target population 205,890,882 inhabitants). METHODS: Overall, 18,980 randomly selected subjects were interviewed (participation rate 80.4%). These subjects were representative of the general population of the UK, Germany, Italy, Portugal, and Spain. They were interviewed by telephone using the Sleep-EVAL expert system, which provided narcolepsy diagnosis according to the International Classification of Sleep Disorders (ICSD). RESULTS: Excessive daytime sleepiness was reported by 15% of the sample, with a higher prevalence in the UK and Germany. Napping two times or more in the same day was reported by 1.6% of the sample, with a significantly higher rate in Germany. Cataplexy (episodes of loss of muscle function related to a strong emotion), a cardinal symptom of narcolepsy, was found in 1.6% of the sample. An ICSD narcolepsy diagnosis was found in 0.047% of the sample: The narcolepsy was severe for 0.026% of the sample and moderate in 0.021%. CONCLUSION: This is the first epidemiologic study that estimates the prevalence of narcolepsy in the general population of these five European countries. The disorder affects 47 individuals/100,000 inhabitants.     

Prevalence of depressive episodes with psychotic features in the general population

OBJECTIVE: The study evaluated the prevalence of major depressive episodes with psychotic features in the general population and sought to determine which depressive symptoms are most frequently associated with psychotic features. METHOD: The sample was composed of 18,980 subjects aged 15-100 years who were representative of the general populations of the United Kingdom, Germany, Italy, Portugal, and Spain. The participants were interviewed by telephone by using the Sleep-EVAL system. The questionnaire included a series of questions about depressive disorders, delusions, and hallucinations. RESULTS: Overall, 16.5% of the sample reported at least one depressive symptom at the time of the interview. Among these subjects, 12.5% had either delusions or hallucinations. More than 10% of the subjects who reported feelings of worthlessness or guilt and suicidal thoughts also had delusions. Feelings of worthlessness or guilt were also associated with high rates of hallucinations (9.7%) and combinations of hallucinations and delusions (4.5%). The current prevalence of major depressive episode with psychotic features was 0.4% (95% CI=0.35%-0.54%), and the prevalence of a current major depressive episode without psychotic features was 2.0% (95% CI=1.9%-2.1%), with higher rates in women than in men. In all, 18.5% of the subjects who fulfilled the criteria for a major depressive episode had psychotic features. Past consultations for treatment of depression were more common in depressed subjects with psychotic features than in depressed subjects with no psychotic features. CONCLUSIONS: Major depressive episodes with psychotic features are relatively frequent in the general population, affecting four of 1,000 individuals. Feelings of worthlessness or guilt can be a good indicator of the presence of psychotic features.     

Can valerian improve the sleep of insomniacs after benzodiazepine withdrawal?

PURPOSE: The authors studied the sleep of patients with insomnia who complained of poor sleep despite chronic use of benzodiazepines (BZDs). The sample consisted of 19 patients (mean age 43.3+/-10.6 years) with primary insomnia (DSM-IV), who had taken BZDs nightly, for 7.1+/-5.4 years. The control group was composed of 18 healthy individuals (mean age 37+/-8 years). Sleep electroencephalogram (EEG) of the patients was analyzed with period amplitude analysis (PAA) and associated algorithms, during chronic BZD use (Night 1), and after 15 days of a valerian placebo trial (initiated after washout of BZD, Night 2). Sleep of control subjects was monitored in parallel. RESULTS: Valerian subjects reported significantly better subjective sleep quality than placebo ones, after BZD withdrawal, despite the presence of a few side effects. However, some of the differences found in sleep structure between Night 1 and Night 2 in both the valerian and placebo groups may be due to the sleep recovery process after BZD washout. Example of this are: the decrease in Sleep Stage 2 and in sigma count; the increase in slow-wave sleep (SWS), and delta count, which were found to be altered by BZD ingestion. There was a significant decrease in wake time after sleep onset (WASO) in valerian subjects when compared to placebo subjects; results were similar to normal controls. Nonetheless, valerian-treated patients also presented longer sleep latency and increased alpha count in SWS than control subjects. CONCLUSIONS: The decrease in WASO associated with the mild anxiolytic effect of valerian appeared to be the major contributor to subjective sleep quality improvement found after 2-week of treatment in insomniacs who had withdrawn from BDZs. Despite subjective improvement, sleep data showed that valerian did not produce faster sleep onset; the increase in alpha count compared with normal controls may point to residual hyperarousabilty, which is known to play a role in insomnia. Nonetheless, we lack data on the extent to which a sedative drug can improve alpha sleep EEG. Thus, the authors suggest that valerian had a positive effect on withdrawal from BDZ use.     

Diagnosis and management of cystic duct leakage after laparoscopic cholecystectomy, report of 3 cases

BACKGROUND： Operative complications after laparoscopic cholecystectomy （LC） vary. Abdominal pain and other symptoms caused by fluid accumulation in the operative area are not uncommon. Cystic duct （CD） leakage is one of the main sources of the fluid. This study was to evaluate the procedures used in the diagnosis and management of CD leakage after LC. METHOD： The clinical materials of 3 patients with CD leakage after LC were studied retrospectively.     

Sleep disturbances and psychiatric disorders associated with posttraumatic stress disorder in the general population

The aim of the study was to assess sleep disturbances in subjects with posttraumatic stress disorder (PTSD) from an urban general population and to identify associated psychiatric disorders in these subjects. The study was performed with a representative sample of 1,832 respondents aged 15 to 90 years living in the Metropolitan Toronto area who were surveyed by telephone (participation rate, 72.8%). Interviewers used Sleep-EVAL, an expert system specifically designed to conduct epidemiologic studies of sleep and mental disorders in the general population. Overall, 11.6% of the sample reported having experienced a traumatic event, with no difference in the proportion of men and women. Approximately 2% (1.8%) of the entire sample were diagnosed by the system as having PTSD at the time of interview. The rate was higher for women (2.6%) than for men (0.9%), which translated into an odds ratio (OR) of 2.8 (95% confidence interval [CI], 1.3 to 6.1). PTSD was strongly associated with other mental disorders: 75.7% of respondents with PTSD received at least one other diagnosis. Most concurrent disorders (80.7%) appeared after exposure to the traumatic event. Sleep disturbances also affected about 70% of the PTSD subjects. Violent or injurious behaviors during sleep, sleep paralysis, sleep talking, and hypnagogic and hypnopompic hallucinations were more frequently reported in respondents with PTSD. Considering the relatively high prevalence of PTSD and its important comorbidity with other sleep and psychiatric disorders, an assessment of the history of traumatic events should be part of a clinician's routine inquiry in order to limit chronicity and maladjustment following a traumatic exposure. Moreover, complaints of rapid eye movement (REM)-related sleep symptoms could be an indication of an underlying problem stemming from PTSD.