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Fluoride is toxic to neuronal development and its excessive intake during pregnancy cause adverse effects on neonatal development. The present study examined the presence of oxidative stress during maternal exposure of fluoride and the therapeutic strategy of Aloe vera, Curcuma longa and Ocimum sanctum extracts in functional prevention of fluoride led oxidative stress. The pregnant Wistar rats were exposed to 100 ppm fluoride in drinking water and pups born to them were supplemented with phytoextracts daily. On 21st postpartum day, the pups were sacrificed to analyse fluoride and oxidative stress markers. Fluoride exposure significantly increased its accumulation, lipid peroxidation and decreased the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase and glutathione levels in discrete regions of the central nervous system (CNS) of pups indicating oxidative stress and inhibited antioxidant defense. The results implied the vulnerability of developing CNS to fluoride toxicity. On phytoextract supplementation, the oxidant devastation was suppressed by regaining antioxidant homeostasis near normal level proving efficacy and therapeutic strategy. Among the phytoextracts supplemented the Ocimum sanctum is found to be more effective.

The effect of fluoride exposure during gestation and post gestation periods were studied to check the status of oxidant, antioxidant and macromolecular changes in CNS and ameliorative role of antioxidants. The pregnant Wistar albino rats were exposed to 50 and 150 ppm fluoride in drinking water and the pups born to them were used for experimentation. After postpartum, the pups were administered daily selected antioxidants through oral gavage. On 21st postnatal day pups were sacrificed and biochemical parameters were assessed. Fluoride exposure substantially increased the activity/levels of fluoride, LPO, protein oxidation, MAO-B, GOT, GPT and decreased protein thiols, RNA and total proteins in discrete regions of CNS. The findings evidenced fluoride induced dyshomeostasis caused on antioxidants, enzymes, macromolecules and governed the pathophysiological events leading to functional loss in a dose dependent manner. The administration of antioxidants remedied the disquiet caused by high fluoride exposure at extreme vulnerable periods of life.

The nearby extrasolar planet GJ 436b-which has been labelled as a 'hot Neptune'-reveals itself by the dimming of light as it crosses in front of and behind its parent star as seen from Earth. Respectively known as the primary transit and secondary eclipse, the former constrains the planet's radius and mass, and the latter constrains the planet's temperature and, with measurements at multiple wavelengths, its atmospheric composition. Previous work using transmission spectroscopy failed to detect the 1.4-mum water vapour band, leaving the planet's atmospheric composition poorly constrained. Here we report the detection of planetary thermal emission from the dayside of GJ 436b at multiple infrared wavelengths during the secondary eclipse. The best-fit compositional models contain a high CO abundance and a substantial methane (CH(4)) deficiency relative to thermochemical equilibrium models for the predicted hydrogen-dominated atmosphere. Moreover, we report the presence of some H(2)O and traces of CO(2). Because CH(4) is expected to be the dominant carbon-bearing species, disequilibrium processes such as vertical mixing and polymerization of methane into substances such as ethylene may be required to explain the hot Neptune's small CH(4)-to-CO ratio, which is at least 10(5) times smaller than predicted.