Monte Carlo simulations of photodynamic therapy in human blood model.

This study aims to simulate a therapeutic plan for a normal human blood model under various patho-physiological conditions, such as the development of leukemia/blood diseases, by means of Monte Carlo multilayered simulation. The photosensitizing compound selectively accumulates in the target cells. A superficial treatment of a blood sample was performed at different ratios of oxygen saturation ([Formula: see text]) under the concentration ([Formula: see text] = 30 µM) effect of merocyanine 540 (MC540) in the blood irradiation. This was done under the application of visible light of wavelength ~ [Formula: see text] at an exposure time ~ 60 s. The dose of photodynamic therapy (PDT) was evaluated for the biological damage, leading to necrosis and blood damage during the treatment. In addition, the effect of PDT treatment response in the blood is related to hemoglobin oxygen saturation, resulting in an excellent relationship between the changes caused by the treatment in the blood at a peculiar oxygen saturation rate (for the highest response: [Formula: see text] 50%) and a light dose (LD) of 3.83 [Formula: see text] above the minimal toxicity of normal tissues. The photodynamic dose is related to the depth of necrosis and the time of treatment for the achievement of the LD delivery at the PDT of blood.

Health and well-being among physicians.

BACKGROUND AND AIM: Physicians' attitudes towards disease prevention are crucial. The purposes of this study are to examine the prevalence of cardiovascular risk factors and adherence to international preventive screening programmes by a group of physicians. METHODS: Online and paper format questionnaires were completed by a sample of 650 physicians from November 2010 to March 2011. The collected data included the main components of screening programmes, which are recommended in international guidelines. RESULTS: The data show that 30.5% of male physicians currently smoke, 19.4 % are obese, 15.2% have hypertension, 38% are physically inactive and 10.9% have diabetes. Nearly all (95%) of the female participants and most (83%) of the male participants older than 45 years had never had a colonoscopy. Of the male physicians older than 55 years, 36.4% had never had prostate-specific antigen testing, and only 10.9% had undergone a digital rectal examination. Among the female physicians, 27.4% were obese, and 42% had never had a mammogram. CONCLUSION: The prevalence of behavioural risk factors for cardiovascular disease is high among physicians. A substantial percentage of the practising physicians did not adhere to the age-specified preventive screening measures recommended in international guidelines.