Mitochondrial DNA damage as a biomarker for ultraviolet radiation exposure and oxidative stress.

The skin is regularly exposed to the harmful effects of sunlight, such as ultraviolet radiation (UVR), which leads to ageing effects as well as clinical precancerous lesions and skin cancer. The accumulation of mitochondrial DNA (mtDNA) damage has been strongly associated as an underlying cause of the general ageing process in tissues and mtDNA damage has been associated with cancer development in many tissues including human skin. This scenario is linked to the key roles of mitochondrial function and mtDNA both in terms of energy production and also oxidative stress production as well as a mediator of apoptosis. We and others have pioneered the use of mtDNA damage as a highly sensitive biomarker of UVR exposure and oxidative stress in human skin; furthermore, ageing-dependent mtDNA mutations can be accelerated by exposure to sunlight. In addition, this review will also highlight useful applications of mtDNA as a biomarker of UVR-induced oxidative stress including effects of antioxidants.

Risk of malignancy index in the preoperative evaluation of pelvic masses.

OBJECTIVES: To assess the ability of a risk malignancy index (RMI) based on serum levels of CA 125, ultrasound findings, and menopausal status to discriminate between benign and malignant pelvic masses in a particular population. METHODS: A retrospective study was conducted of 100 women with pelvic masses admitted for laparotomy. The sensitivity and specificity of serum levels of CA 125, ultrasound findings, and menopausal status were calculated both separately and combined into a RMI to diagnose malignancy. RESULTS: The RMI was more accurate than any single criterion in diagnosing malignancy. Using a cut-off level of 200 to indicate malignancy, the RMI gave a sensitivity of 90%, specificity of 89%, positive predictive value of 96%, and negative predictive value of 78%. CONCLUSION: The RMI is able to correctly discriminate between malignant and benign pelvic masses. It is a simple scoring system that can be introduced easily into clinical practice to facilitate the selection of patients who would benefit from primary surgery.