[Evaluation of an automated system of immunofluorescence analysis in daily practice]. / Évaluation des performances d'un système automatisé de lecture d'immunofluorescence en pratique quotidienne.

Since a few years indirect immunofluorescence (IIF) enjoys automated screening. These automated systems give an interpretation for the detection of anti-nuclear (ANA) and anti-neutrophil cytoplasmic antibodies (ANCA) and take images in the case of the research of anti-tissue antibodies. We propose an evaluation of the Image Navigator® system for all these kinds of research. 1,435 sera samples are included: 810 for ANA detection, 450 for ANCA detection, 175 for anti-tissue antibodies research. Visual interpretation using microscope is compared to automated interpretation and visual interpretation using the pictures. Sensibility of the automated interpretation to artifacts is assessed too. Accordance between automated interpretation and visual interpretation using microscope is moderate (kappa=0.46) in the case of ANA detection, poor in the case of ANCA detection (kappa=0.30). Accordance between visual interpretation using microscope and visual interpretation using pictures is strong for ANA (kappa=0.79) and for ANCA (kappa=0.63), very strong for anti-tissues antibodies (kappa=0.87). The blur of more than one photography interferes with the interpretation of the system (p<0.01). In any case, a second reading is necessary. The results of our study validate the use of the pictures for the interpretation of AAN but require visual interpretation using microscope for ANCA. The screening of anti-tissue antibodies can be achieved using pictures.

Polyphenols decreased liver NADPH oxidase activity, increased muscle mitochondrial biogenesis and decreased gastrocnemius age-dependent autophagy in aged rats.

This study explored major systems of reactive oxygen species (ROS) production and their consequences on oxidative stress, mitochondriogenesis and muscle metabolism in aged rats, and evaluated the efficiency of 30-day oral supplementation with a moderate dose of a red grape polyphenol extract (RGPE) on these parameters. In the liver of aged rats, NADPH oxidase activity was increased and mitochondrial respiratory chain complex activities were altered, while xanthine oxidase activity remained unchanged. In muscles, only mitochondrial activity was modified with aging. The oral intake of RGPE decreased liver NADPH oxidase activity in the aged rats without affecting global oxidative stress, suggesting that NADPH oxidase was probably not the dominant detrimental source of production of O(2)·(-) in the liver. Interestingly, RGPE supplementation increased mitochondrial biogenesis and improved antioxidant status in the gastrocnemius of aged rats, while it had no significant effect in soleus. RGPE supplementation also decreased age-dependent autophagy in gastrocnemius of aged rats. These results extended existing findings on the beneficial effects of RGPE on mitochondriogenesis and muscle metabolism in aged rats.