Assessment of bioavailability of gold bhasma in human participants – A pilot study

Bioavailability of the well-known Ayurvedic drug Swarnabhasma (gold bhasma or calcined gold) is unknown. It is orally administered either sublingually or directly with various Anupanas like black pepper powder (Piper nigrum Linn.) and cow ghee in the dose range of 15–240 mg by Ayurvedic physicians. Study of bioavailability of Swarnabhasma is necessary as this metal-derived drug is administered for long duration for rejuvenation. The pilot study was carried out in healthy human male participants to assess bioavailability of Swarnabhasma in three doses, viz. 30 mg plain sublingual, 30 mg oral dose mixed with black pepper powder (250 mg) and cow ghee (2.5 gm); and 240 mg oral dose mixed with black pepper powder (250 mg) and cow ghee (2.5 gm). Blood samples were withdrawn at 0, 1, 2 and 4 h after administration of dose. Estimation of gold levels in blood was carried out by inductively coupled plasma mass spectrometry (ICP-MS). Results show that gold is absorbed in traces from single dose of Swarnabhasma. Maximum concentration of gold was bioavailable from 30 mg sublingual dose with Cmax 0.983 μg/L at 2 h (Tmax). Oral dose of 30 mg Swarnabhasma mixed with black pepper powder and ghee showed faster absorption with Tmax at 1 h and Cmax 0.867 μg/L, and 240 mg dose with black pepper and ghee showed Cmax 0.668 μg/L and Tmax at 2 h

Exceptional anoxia resistance in larval tiger beetle, Phaeoxantha klugii (Coleoptera : Cicindelidae)

The tiger beetle Phaeoxantha klugii inhabits Central Amazonian floodplains, where it survives the annual inundation period in the third-instar larval stage submerged in the soil at approximately 29 degreesC for up to 3.5 months. Because flooded soils quickly become anoxic, these larvae should be highly resistant to anoxia. The survival of adult and larval P. klugii was therefore tested during exposure to a pure nitrogen atmosphere in the laboratory at 29 degreesC. Adult beetles were not resistant (< 6 h). Survival of larvae decreased over time, maximum survival was 15 days, whereas time to 50% mortality was 5.7 days (95% confidence interval 3.8-7.9). Anoxia resistance was additionally tested in third-instar larvae submerged within sediment for 40 days before anoxia exposure in the laboratory. Anoxia resistance was greatly enhanced in these larvae, showing a survival rate of 50% after 26 days of anoxia exposure. It appears that the gradual flooding process and/or the submersion phase induced a physiological alteration, most probably a strong depression in metabolic rate, which requires some days for induction. The degree of anoxia resistance in larval P. klugii is remarkable among terrestrial arthropods worldwide, even more so considering the high ambient temperatures. The species is well-suited to serve as a model organism for studying the physiological mechanisms of anoxia and submersion resistance in terrestrial arthropods inhabiting tropical floodplains