Clastogenic Factors as Potential Biomarkers of Increased Superoxide Production

The formation of clastogenic factors (CF) and their damaging effects are mediated by superoxide, since superoxide dismutase is regularly protective. CF are produced via superoxide and stimulate the production of superoxide by monocytes and neutrophils. This results in a selfsustaining and longlasting process of clastogenesis, which may exceed the DNA repair system and ultimately lead to cancer (Emerit, 1994). An increased cancer risk is indeed observed in conditions accompanied by CF formation. These include irradiated persons, patients with chronic inflammatory diseases, HIV-infected persons and the chromosomal breakage syndromes ataxia telangiectasia, Bloom’s syndrome and Fanconi’s anemia. Biochemical analysis has identified lipid peroxidation products, arachidonic acid metabolites, nucleotides of inosine and cytokines, in particular tumor necrosis factor alpha, as the clastogenic and also superoxide stimulating components of CF. Due to their chromosome damaging effects, these oxidants can be detected with classical cytogenetic techniques. Their synergistic action renders the CF-test particularly sensitive for the detection of a pro-oxidant state. Correlations were observed between CF and other biomarkers of oxidative stress such as decreases in total plasma thiols or increases in TBARS or chemiluminescence. Correlations between CF and disease activity, between CF and radiation exposure, suggest the study of CF for monitoring these conditions. CF may also be useful as biochemical markers and intermediate endpoints for the evaluation of promising antioxidant drugs

New chronometric insights into ancient egyptian musical instruments held at the Musée du Louvre and the Musée des Beaux-arts de Lyon

International audienceVery little is known about the manufacturing and use of ancient Egyptian instruments, and their discovery is very rare. An extensive radiocarbon (14C) dating program has been conducted on 25 ancient Egyptian musical instruments currently held at the Louvre Museum (musée du Louvre) and the Lyon Museum of Fine Arts (musée des Beaux-Arts de Lyon). This study includes cordophones (harps, lyres, lutes), membranophones (drums, tambourines), idiophones (clappers, crotales), as well as wind instruments (oboe) that have entered the museum collections during the 19th century or the first half of the 20th century; consequently, the original archaeological contexts of their discoveries are poorly understood. Approximately 50 14C dates enable drawing a general overview of the instruments manufacturing. A wide variety of wood material has been identified, representing both indigenous species and imported species. Results indicate that the native flora of Egypt was exclusively used until the Third Intermediate Period when the first imports could be identified. 14C results are not always consistent with relative dates previously thought, mainly based on stylistic criteria. They demonstrate these collections hold very well-preserved objects extending over 2500 years, from the Second Intermediate Period (ca. 1700 BCE) to the start of the Islamic Period (8th century CE). This project provides important results for the knowledge of ancient Egyptian musical instrument crafts

Oxidative Stress in Chronic Hepatitis C: The Effect of Interferon Therapy and Correlation with Pathological Features

AIMS: To evaluate the oxidative stress parameters before, during and after interferon treatment