An assessment on resveratrol and its cellular protective properties

Abstract only availableResveratrol is a polyphenolic compound found abundantly in plants such as knotweed or grapes. Under normal circumstances, it is in plants as a phytoalexin - an antibiotic produced by plants for defense under insults. Based on previous studies, it it also has properties that protect cells from damage caused by free radicals or reactive oxygen species In order to test the effectiveness of resveratrol as a protective agent, an experiment was designed using an immortalized astrocyte cell line, DiTNC. These cells were divided into control, resveratrol and non-resveratrol groups. They were cultured in a standard six well plate, with two wells per group. Menadione (25 and 50 micromolar), a compound that generates reactive oxygen species in cells, was added to four wells, two of which contained pre-incubated resveratrol (50 micromolar). The cells were left to incubate in an incubating oven at 37 Celsius. Photos are taken at intervals of 30 minutes, 60 minutes, and 120 minutes. Menadione caused cells to project processes and then causes them to become shrunken and rounded within 30 min. When the pictures from the resveratrol group was compared to the non-resveratrol group, a significantly less amount of cells from the resveratrol group were found to be either free floating or shrunken, suggesting that these cells survived for a longer period. An MTT test will also be performed in order to quantify the data. The results show that resveratrol has a fair effect on protecting cells from reactive oxygen species and that this chemical warrants further investigations.Alzheimer's disease program project grant 2P01AGO18357 to G. Su

Mechanism of In-Situ Catalytic Cracking of Biomass Tar over Biochar with Multiple Active Sites

Biomass tar is the bottleneck in the development of efficient utilization of biomass syngas. The in-situ catalytic cracking biomass tar with multi-active biochar is investigated in a two-stage fluidized bed-fixed bed reactor. It indicates that adding H2O or CO2 is found to improve the homogeneous and heterogeneous cracking of biomass tar. Activation of biochar by H2O or CO2 impacted the morphology of biochar surface and distribution of metal species. H2O or CO2 affects the creation and regeneration of pore structures, influencing the biochar structure and dynamical distribution of alkali and alkaline earth metal species (AAEMs), which ensure enough surface active sites to maintain the catalytic activity of biochar. The tar cracking into low-quality tar or small-molecule gas may be catalyzed by K, while the combination of tar with biochar would be promoted by Ca. The volatilizations of K and Ca, due to their reaction with volatiles, are to a large extent in accordance with their valences and boiling points. The subsequent transformation from the small aromatic ring systems to the larger ones occurs due to the volatile-biochar interaction. During tar cracking over biochar, K and Ca act as the active sites on biochar surface to promote the increase of active intermediates (C▬O bonds and C▬O▬K/Ca)

Lightweight photovoltaic composite structure on stratospheric airships

A semirigid solar array is an efficient energy system on the surface of stratospheric airships for utilizing the solar energy, which we believe that it has succeeded in providing some impressive results for conceptual design. This paper developed a lightweight photovoltaic composite structure (LPCS) according to the characteristics of the stratospheric airship capsule. In order to improve the flexibility of the solar cell, we studied the mechanical properties in the different thicknesses of the honeycomb core for LPCS by FEM software and three-point bending test, and we also launched experiments to measure the temperature difference between upper and lower surfaces of the LPCS test samples under different solar radiation flux conditions. The experimental data were examined to evaluate the mechanical properties and thermal insulation performances of LPCS. Considering the quality of the whole structure, the paper finally comes up with the conclusion of the optimal thickness of the honeycomb core with further detailed descriptions

The Synergistic Effect of Valsartan and LAF237 [(S)-1-[(3-Hydroxy-1-Adamantyl)Ammo]acetyl-2-Cyanopyrrolidine] on Vascular Oxidative Stress and Inflammation in Type 2 Diabetic Mice

Aim. To investigate the combination effects and mechanisms of valsartan (angiotensin II type 1 receptor blocker) and LAF237 (DPP-IV inhibitor) on prevention against oxidative stress and inflammation injury in db/db mice aorta. Methods. Db/db mice (n = 40) were randomized to receive valsartan, LAF237, valsartan plus LAF237, or saline. Oxidative stress and inflammatory reaction in diabetic mice aorta were examined. Results. Valsartan or LAF237 pretreatment significantly increased plasma GLP-1 expression, reduced apoptosis of endothelial cells isolated from diabetic mice aorta. The expression of NAD(P)H oxidase subunits also significantly decreased resulting in decreased superoxide production and ICAM-1 (fold change: valsartan : 7.5 ± 0.7, P < 0.05; LAF237: 10.2 ± 1.7, P < 0.05), VCAM-1 (fold change: valsartan : 5.2 ± 1.2, P < 0.05; LAF237: 4.8 ± 0.6, P < 0.05), and MCP-1 (fold change: valsartan: 3.2 ± 0.6, LAF237: 4.7 ± 0.8; P < 0.05) expression. Moreover, the combination treatment with valsartan and LAF237 resulted in a more significant increase of GLP-1 expression. The decrease of the vascular oxidative stress and inflammation reaction was also higher than monotherapy with valsartan or LAF237. Conclusion. These data indicated that combination treatment with LAF237 and valsartan acts in a synergistic manner on vascular oxidative stress and inflammation in type 2 diabetic mice