ABSTRACT
Fenofibrate is a common lipid-lowing drug activating peroxisome proliferator-activated receptor alpha (PPRAα).Recent studies have found that fenofibrate possesses anticancer properties.Its specific mechanisms include inhibiting cell metabolism and formation of new tumor vessels,arresting cell circle,weakening cell motility,and inducing cell apoptosis.Those properties are partly independent of PPRAα.Due to its low side-effects,it's hopefully to be used as an anticancer adjuvant drug.
ABSTRACT
To reveal the mechanism of Cu enrichment of alfalfa, in-situ micro-X-ray fluorescence spectrometry (μ-XRF) and fractional extraction were used to explore in-situ Cu distribution information in alfalfa seedlings and different combination forms of Cu in organs.The results showed that alfalfa roots were enriched with Cu up to 12.06 mg/g, which was 8 times of stem and 4.9 times of leaves.The in-situ μ-XRF result showed that the root of alfalfa was the main site of enrichment of Cu, and there was a barrier of Cu at the rhizome junction to alleviate the toxic effect of excess Cu on the shoots.Excess Cu (more than 50 μmol/L) also inhibited the uptake of Zn and Ca in alfalfa, enhanced the uptake of Fe in alfalfa, but had no obvious effect on the uptake of K and Mn.Plant fractional extraction showed that the Cu in root cells was mainly fixed in the form of insoluble residues (41%) and cell wall chelate (20%), while in the stem, Cu existed as four forms including hydrophobic protein binding, cell wall binding state, residual state and water-soluble state, which further reduce the excess transport of Cu to the leaves.In the leaves, excess Cu in the leaf cells was mainly in the vacuole and insoluble residue to achieve tolerance and detoxification to Cu.
ABSTRACT
Moss has high tolerance and accumulating capacity to heavy metal.In this study, the distribution of heavy metal elements in moss sampled from lead-zinc mine was analyzed by X-ray fluorescence spectrometry.The speciation of lead was analyzed by X-ray absorption near-edge spectroscopy.Research showed that the contents of Pb, Zn, Cd and As in the moss of the mining area were extremely high, and their maximum concentration were 1.06 mg/g , 1.23 mg/g, 30.5 μg/g, 13.2 μg/g, respectively.Besides, the shoots especially the new tissue of the moss were the major sites for accumulation and storage of heavy metals.The micro-distribution characteristics varied among Hypnum plumaeforme and Brachytheciumprocumbens, indicating the difference of different species of moss in absorption pathway, accumulation and tolerance mechanisms for heavy metal.Linear combination fitting results indicated that the main lead speciation in moss was lead phosphate (78%) and lead oxide (22%), which suggested that the precipitation of lead phosphate might be the main mechanism of tolerance for moss.