Pathophysiological mechanism of seasonal affective disorder.

Despite the long history in medicine, the pathophysiological mechanism(s) of seasonal affective disorder (SAD) remain largely unknown. By employing a meta-analytic methodology, the authors of this study attempted to verify the validity of different pathophysiological mechanism(s) proposed for SAD. The findings showed that for phototherapy of medium light intensity, a combination of morning-evening therapy regime yielded the best therapeutic effect, and the antidepressant effect of the morning-evening light regime was superior to a single pulse of light administered at other times of day. Furthermore, the data showed that the antidepressant effect of a single pulse of light was similar for morning, midday, and evening light. These findings supported the photon-count hypothesis and refuted the proposed photoperiod, melatonin, and phase-shifting models of SAD.

Spectral properties of phototherapy for seasonal affective disorder: a meta-analysis.

The general therapeutic effect of light on seasonal affective disorder (SAD) has been widely acknowledged. However, the antidepressant effect of light does not seem to be the same for different spectra of light. In this study, the authors attempted to study the spectral properties of phototherapy for SAD using a meta-analytical procedure. The findings suggested that light of short to medium wavelengths (blue/green/yellow) seem to be essential for the therapeutic effect of light on SAD. Red wavelengths were relatively ineffective. It was then postulated that SAD may be predisposed and/or precipitated by the inefficiency of the S and M cones in the retina. Furthermore, ultraviolet (UV) waves did not seem to be essential for SAD symptom alleviation by artificial light. Therefore, these potentially harmful UV waves should be blocked in any clinical application of phototherapy for SAD.

The effect of occupational therapy education on students' perceived attitudes toward persons with disabilities.

OBJECTIVES: The effect of occupational therapy education on students' perceived attitudes toward persons with disabilities was studied. METHOD: The perceived attitudes of 144 occupational therapy students toward persons with disabilities were measured before (retrospective pretest) and after (posttest) the students attended formal professional education at the University of Alberta. RESULTS: Posttest scores were significantly higher than the retrospective pretest scores, indicating that students' attitudes became more positive after they commenced formal professional education. The posttest scores of students at various levels of education, however, did not show any significant difference. CONCLUSION: On the basis of these observations, a positive but nonlinear relationship between occupational therapy education and attitudes toward persons with disabilities was postulated.

Cervical cancer screening: women's knowledge, attitudes and preferences.

Screening status of women aged 20-64 registered with a large group practice was determined using laboratory and general practice records. A postal survey was carried out on 1,416 women divided into: 1. 'Non-attenders'--never had a smear. 2. 'Defaulters'--smear more than five years ago. 3. 'Attenders'--smear in last five years. Screening status was related to social class and education. Single and nulliparous women were less likely to have been screened. Knowledge of the test was poor in all three groups. Most women were willing to have a smear performed and previous non-attendance might have been overcome by a call/recall system. The woman's general practitioner was the preferred taker of smears, regardless of sex. Of those willing to have the test 95% would attend the general practitioner if no alternative was provided. Improved uptake depends on an organised call/recall system with smear taking based in primary care, and on improved health education.

Parkinson's disease in a Scottish city.

In a detailed community study the total prevalence of idiopathic Parkinson's disease in Aberdeen was 164.2/10(5) of the population. The age and sex specific prevalence rose to 2657.8/10(5) (2.7%) of men and 2071.0/10(5) (2.0%) of women aged over 84. The mean age at onset, irrespective of sex, was 65.3 years (SD 12.6) and varied little compared with similar studies over the past 25 years. Half of patients were independent but 78/225 (34.7%) were considerably disabled and 23/225 (10.2%) were confined to bed or a wheelchair. Disability increased with age and also with a low minimental state questionnaire score. The score was less than or equal to 7/10 (graded 0-10) in 93/252 (37%) of patients and less than 5/10 in 28/252 (11%). Parkinson's disease remains a common and disabling condition in the community.

A hazard associated with improper connection of the Bain breathing circuit.

A case of cardiac arrest is presented which was caused by improper connection of a modified Mapleson D circuit (Bain breathing circuit). Excessive enternal deadspace was created by interchanging the gas inflow line and the attachment for an airway pressure manometer. This resulted in a marked respiratory acidosis, clinically undetected until the concomitant hypoxia produced a severe cardiac depression and arrest. The sequence of events was reproduced in a dog under comparable anaesthetic conditions. In order to avoid this error it is recommended to permanently fuse the connecting piece placed in the circuit with the tubing leading to the airway pressure manometer of the respirator.