Rosuvastatin relieves neuronal mitochondrial damage by regulating UCP2-SIRT3 pathway after cerebral ischemia/reperfusion / 中国药理学通报

Aim To explore the biological role and related mechanism of rosuvastatin (RS) in mitochondrial damage of neurons after cerebral ischemia/reperfusion (CIR) through UCP2-SIRT3 signaling pathway. Methods Human neuroblastoma cell (SH-SY5Y cell) cerebral infarction reperfusion model (OGD/R) was established, different concentrations of RS (40 and 2. 5 (mol • L

UV-screening of grasses by plant silica layer.

UV-screening by terrestrial plants is a crucial trait since colonization of terrestrial environments has started. In general, it is enabled by phenolic substances. Especially for grasses it remains unclear why plants grown under the absence of UV-B-radiation exhibit nonetheless a high UV-B-screening potential. But this may be explained by the UV-screening effect of the silicon double layer. It was shown for seedlings of soybeans (Glycine max L.) and wheat (Triticum aestivum L.) that enhanced silicon supply reduces stress induced by UV-radiation. Even more important is a direct correlation between silicon content in the epidermis near area (intercellular spaces) and the absorption of UV-radiation in this area shown in other papers. The silicon double layer may act like a glass layer and decreases the transmission of UV-radiation at the epidermis near area. In summary, the absorbance/reflection of ultraviolet radiation is dependent on the characteristics of the epidermis near area of leaves, particularly the occurrence (qualitatively and quantitatively) of phenolic substances and/or a silicon double layer in this area. Consequently, UV-screening by plant silicon double layer should get more attention in future research with emphasis on effects of UV-radiation on plant physiology.

Characterization of biominerals in species of Canna (Cannaceae)

Plant biominerals are not always well characterized, although this information is important for plant physiology and can be useful for taxonomic purposes. In this work, fresh plant material of seven wild neotropical species of genus Canna, C. ascendens, C. coccinea, C. indica, C. glauca, C. plurituberosa, C. variegatifolia and C. fuchsina sp. ined., taken from different habitats, were studied to characterize the biominerals in their internal tissues. For the first time, samples from primary and secondary veins of leaves were investigated by means of infrared spectroscopy, complemented with X-ray powder diffractometry and scanning electron microscopy. The spectroscopic results, supported by X-ray powder diffractometry, suggest that the calcium oxalate is present in the form of whewellite (CaC2O4×H2O) in all the investigated samples. It is interesting to emphasize that all IR spectra obtained were strongly similar in all species studied, thus indicating an identical chemical composition in terms of the biominerals found. In this sense, the results suggest that the species of Canna show similar ability to produce biogenic silica and produce an identical type of calcium oxalate within their tissues. These results can be an additional trait to support the relationship among the families of Zingiberales. Rev. Biol. Trop. 58 (4): 1507-1515. Epub 2010 December 01.

Los biominerales de las plantas no siempre han sido bien caracterizados aunque esta información es importante en fisiología vegetal y puede ser de utilidad para fines taxonómicos. En este trabajo se estudió material vegetal fresco de siete especies silvestres neotropicales: Canna, C. ascendens, C. coccinea, C. indica, C. glauca, C. plurituberosa, C. variegatifolia and C. fuchsina sp. ined., provenientes de diferentes localidades, con el fin de caracterizar los biominerales presentes en sus tejidos foliares internos. Por vez primera, muestras de venas primarias (ejes foliares) y secundarias de hojas de estas especies se investigaron por medio de espectroscopia de infarrojo, complementada con estudios por difracción de rayos X de polvos y microscopía electrónica de barrido. Los resultados indicaron la presencia de ópalo (sílice biogénica) y oxalato de calcio en los tejidos vegetales analizados. Además, se determinó que el oxalato de calcio está presente en forma de whewellita (CaC2O4×H2O), información nueva para el género. Tanto el ópalo como la whewellita están presentes en todas las especies analizadas, que representan aproximadamente un tercio de las especies silvestres del género. La capacidad de biomineralizar SiO2 en forma de ópalo en especies de Canna de diversos ambientes resulta también un rasgo altamente sugerente para futuros estudios.

Study on Osteoblasts Growth on Opal Powder/Poly-L-Lactic Acid Composite Films / 航天医学与医学工程

Objective To find a new material for biomedical scaffold.Methods Composite films from poly-L-lactic acid(PLLA)and opal powder were fabricated.Osteoblasts seeded on the composite films and control ones were examined.Cell densities and morphologies on these films were studied by scanning electron microscopy(SEM).Cell growth and differential function were assessed by 3-(4,5-dimethyltyiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)test.Results SEM study showed that the addition of powder could improve the adhesion between osteoblasts and the composite films.MTT test proved that cell proliferation was improved when opal powder was added.This improvement came from the negative ion given off by the opal powder.The negative ions either accumulate at the cell membrane or enter into the cells.Accumulation of negative ions at the cell membrane leads to a change of electric potential difference across the cell membrane which should be in a proper range for the cells to perform their normal physiological function.If the negative ions enter the cells,they may take part in biochemical reactions whenever possible.In this way,the ions also affect the cell normal metabolism.Conclusion Osteoblasts grow well on opal/PLLA composites and the negative ion from opal powder is responsible for the enhancement of cell growth.This study provides a new material for biomedical scaffold.