To tackle the difficult problem of large ethnomedicine compound prescription research in a fast and efficient way, high-speed separation of Baimai prescriptions was performed by automated flash chromatography on 100-g Si flash columns at a flow-rate of 40 mL/min. Petroleum ether, methylene dichloride, ethyl acetate, methanol and water were used in gradient elution solvent system. 69 fractions were obtained as an ethnodrug compounds library. Separation degree of partial fractions were determined by HPLC-UV absorption spectrometry. Antioxidant activities screening of the fractions in 96 well plates was carryied out. Distribution range of fractions with strong scavenging effect of free radical DPPH was identified. Fraction 5-18 and 20 extracted from ethyl acetate exert the strongest antioxidant activities in vitro, and are identified as effective-composite of the prescription in radical scavenging. The results reported here suggest that the methods used may lead to improvements in the research and development of large ethnomedicine compound prescription.
To research the effects and mechanisms of recombinant human ciliary neurotrophic factor (rhCNTF) on ischemia/reperfusion in vivo and in vitro, rhCNTF was biosynthesized, and ischemia/reperfusion-like models were used. Protection by rhCNTF was studied at the in vivo level using a model of middle cerebral artery occlusion and reperfusion (MCAO/R) in rats. RhCNTF was administrated just before reperfusion. RhCNTF markedly increased animal viability, decreased infarct volumes and neurological deficit scores. Primary cortical neuronal cultures were subjected to oxygen-glucose deprivation/reoxygenation, and treated with rhCNTF prophylactically. Results indicated that neuronal survival rates were increased, LDH release was decreased and lose of neurite length were alleviated in rhCNTF group, and this protection was associated with nerotrophic effect, nitric oxide and neuronal nitric oxide synthase (nNOS) and inducible NOS (iNOS). The data suggest that rhCNTF may be a good therapeutic reagent to reduce cerebral ischemia/reperfusion injury, and may act by NOS regulation.
As there was no precise theoretical model for predicting the stress of deformation zone while straightening thin-walled tube, some technological parameters depended mostly on the experience of workers and on the results of trials, therefore by means of the membrane shell theory the equilibrium differential equations of stress is obtained firstly, then we analyze the strain of deformation zone, finally lead to a new theoretical model for predicting the stress in the elastic and plastic zone. Subsequently the simulated experiments have been done, the results show that the theoretical calculations coincide well with the simulated results, the errors are within 1%of the calculations, it is testified that the model is correct and efficient for the thin-walled tube straightening.
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