Laser photobioactivation mechanisms: in vitro studies using ascorbic acid uptake and hydroxyproline formation as biochemical markers of irradiation response

Clinical investigations of laser photobioactivation, or biostimulation, might be differently designed and more fruitful if knowledge of basic biochemical mechanisms were better understood. In this investigation, biochemical events identified as responses to 904 nm irradiation included increased ascorbic acid uptake by fibroblasts. These cells also showed increased hydroxyproline formation, and this was increased several-fold by the addition of proline to the medium. Maximum biochemical responses were observed at a pulse frequency of 67 Hz and a pulse width of 150 nsec with an energy density of approximately 7 mJ/cm2 per exposure. Elements in the mitochondrial cytochrome system are proposed as the radiation absorbing chromophore(s). Hypothetically, the energy generated is linked to ascorbic acid uptake, which in turn stimulates collagen synthesis.     

Radiation-induced meningioma after treatment for pituitary adenoma: case report and literature review

Radiation-induced meningiomas are becoming increasingly well-recognized. We report a case of a 35-year-old man who developed a suprasellar meningioma 9 years after receiving a radiation dose of 4480 cGy for a pituitary adenoma. The literature is also reviewed.     

An investigation into nurses' understanding of health education and health promotion within a neuro-rehabilitation setting*

This qualitative study was undertaken at two neuro-rehabihtation centres in England, with the aim of exploring the nurses' understanding of health education and health promotion and their role within it, and their perception of illness and wellness related to disability The principle of methodical triangulation was employed using questionnaires, group interviews and content analysis of client care plans Although the nurses had difficulty distinguishing between health promotion and health education, differences did emerge which were supported by the literature The nurses generally identified their role as being one of health promotion However, they tended to equate wellness with physical independence As a result of the study a health promotion model based on the principles of self-empowerment is suggested, which could be used as a framework for rehabilitation nurses and other professionals to enable them to focus on health and wellness rather than illness and disability     

Symptoms and time to presentation and treatment in ocular melanoma: the Western Canada Melanoma Study

Reports on all ocular melanomas newly diagnosed between Apr. 1, 1979, and Mar. 31, 1981, were obtained from the cancer registries of British Columbia, Alberta, Saskatchewan and Manitoba. Of the 90 cases, 87 were in patients aged 20 to 79 years, 64 of whom were interviewed about their initial symptoms. Three symptoms--loss of part of the visual field (in 33% of patients), photopsia (in 20%) and blurred vision (in 20%)--emerged as the main indicators of disease. In 17% of cases the tumour was discovered as an incidental finding on ocular examination. The length of delay before consulting a physician was generally short in symptomatic patients, with 85% reporting that they saw a physician within 3 months of onset of the first symptom. Of the 30 patients who received definitive treatment 4 months or more after initial presentation, 13 were seen by general practitioners who delayed before referring the patient to an ophthalmologist. Continuing medical education is needed to ensure earlier referral to ophthalmologists by general practitioners of patients with ocular melanoma.     

Cardiac function predicts mortality following thoracoabdominal and descending thoracic aortic aneurysm repair.

OBJECTIVE: Previous studies have identified age, renal failure and aneurysm extent as predictors of mortality following thoracoabdominal and descending thoracic aortic aneurysm (TAA) repair. We studied the impact of coronary artery disease (CAD) and cardiac function on 30-day mortality following TAA repair. METHODS: Between February 1991 and May 2001, we performed 854 TAA repairs. Two hundred ninety-one patients (34%) had a history of coronary artery disease. One hundred forty-one/291 (49%) had undergone coronary artery bypass surgery (CAB) prior to TAA repair. We conducted multivariable analyses of known risk factors along with the left ventricular ejection fraction (EF) and prior CAB to determine the adjusted effect of CAD on outcome. RESULTS: Mortality in patients with CAD was 54/291 (18%) compared to 75/563 (13%) without CAD (P<0.05). In patients who had prior CAB, mortality was 31/141 (22%) compared to 98/713 (14%) patients without prior CAB, (P<0.02). In multivariable analysis, the effects of CAD and CAB on mortality were eliminated by consideration of a low EF (defined as less than 50%). CONCLUSION: Impaired left ventricular function appears to be the strongest cardiac predictor of mortality for TAA repair, independent of the presence of coronary artery disease or coronary artery bypass revascularization.