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The current study was designed to investigate the effect of madecassoside, the major triterpene in CENTELLA ASIATICA, on burn wound healing and its possible mechanism of action. An oral administration of madecassoside (6, 12, 24 mg/kg) facilitated wound closure in a time-dependent manner and reached its peak effect, nearly completely wound closure, on day 20 in the group receiving the highest dose of 24 mg/kg of madecassoside. Further histopathological analysis revealed that madecassoside alleviated infiltration of inflammatory cells as well as enhanced epithelisation resulting from dermal proliferation of fibroblasts. Madecassoside at higher doses (12 and 24 mg/kg) decreased nitric oxide (NO) levels and malondialdehyde (MDA) content in the burn skin tissue. However, reduced glutathione (GSH) and hydroxyproline levels were increased in the same skin tissue. In addition, madecassoside promoted skin angiogenesis IN VIVO, correlating with our findings IN VITRO that it stimulated endothelial cell growth in a rat aortic ring assay. These data suggest that madecassoside has significant wound-healing activity and is one of the major reasons for the use of C. ASIATICA herbs in the successful treatment of burn injury. Moreover, the results from the present study indicate that the effect of madecassoside on wound healing may involve several mechanisms including antioxidative activity, collagen synthesis and angiogenesis.

Available studies, while limited in number, suggest that e-cigarette vaping induces oxidative stress, with one potential mechanism being the direct formation of reactive oxygen species (ROS) in evapor. In the present studies, we measured the formation of hydroxyl radical ( • OH), the most destructive ROS, in e-vapor under a range of vaping patterns (i.e., power settings, solvent concentrations, flavorings). Study results show that increased power output and puff volume correspond with the formation of significantly higher amounts of • OH in e-vapor because of elevated coil temperature and oxygen supply. Vegetable glycerin (VG) e-liquids generated higher *

Air pollution is one of the leading global public health risks but its magnitude in many developing countries’ cities is not known. We aimed to measure the concentration of particulate matter with aerodynamic diameter <2.5 µm (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) pollutants in two Ugandan cities (Kampala and Jinja). PM2.5, O3, temperature and humidity were measured with real-time monitors, while NO2 and SO2 were measured with diffusion tubes. We found that the mean concentrations of the air pollutants PM2.5, NO2, SO2 and O3 were 132.1 μg/m3, 24.9 µg/m3, 3.7 µg/m3 and 11.4 μg/m3, respectively. The mean PM2.5 concentration is 5.3 times the World Health Organization (WHO) cut-off limits while the NO2, SO2 and O3 concentrations are below WHO cut-off limits. PM2.5 levels were higher in Kampala than in Jinja (138.6 μg/m3 vs. 99.3 μg/m3) and at industrial than residential sites (152.6 μg/m3 vs. 120.5 μg/m3) but residential sites with unpaved roads also had high PM2.5 concentrations (152.6 μg/m3). In conclusion, air pollutant concentrations in Kampala and Jinja in Uganda are dangerously high. Long-term studies are needed to characterize air pollution levels during all seasons, to assess related public health impacts, and explore mitigation approaches.

Because of the importance of HONO as a radical reservoir, consistent and accurate measurements of its concentration are needed. As part of SHARP (Study of Houston Atmospheric Radical Precursors), time series of HONO were obtained by six different measurement techniques on the roof of the Moody Tower at the University of Houston. Techniques used were long path differential optical absorption spectroscopy (DOAS), stripping coil‐visible absorption photometry (SC‐AP), long path absorption photometry (LOPAP®), mist chamber/ion chromatography (MC‐IC), quantum cascade‐tunable infrared laser differential absorption spectroscopy (QC‐TILDAS), and ion drift‐chemical ionization mass spectrometry (ID‐CIMS). Various combinations of techniques were in operation from 15 April through 31 May 2009. All instruments recorded a similar diurnal pattern of HONO concentrations with higher median and mean values during the night than during the day. Highest values were observed in the final 2 weeks of the campaign. Inlets for the MC‐IC, SC‐AP, and QC‐TILDAS were collocated and agreed most closely with each other based on several measures. Largest differences between pairs of measurements were evident during the day for concentrations < ~100 parts per trillion (ppt). Above ~ 200 ppt, concentrations from the SC‐AP, MC‐IC, and QC‐TILDAS converged to within about 20%, with slightly larger discrepancies when DOAS was considered. During the first 2 weeks, HONO measured by ID‐CIMS agreed with these techniques, but ID‐CIMS reported higher values during the afternoon and evening of the final 4 weeks, possibly from interference from unknown sources. A number of factors, including building related sources, likely affected measured concentrations.

Polychlorinated biphenyls (PCBs) are classi ed as priority pollutants by environmental agencies. A eld investigation on polychlorinated biphenyls movement and retention in paddy eld was conducted during 1993, 1997 and 1999 at the WenTai area. Soil, air and rice samples were analyzed. PCB concentrations in the soil showed a reducing trend with respect to time and depth. Most of the di-, tri-, and tetra-chlorinated PCB congeners showed signi cant decreases during the period, while the more highly chlorinated PCBs were more persistent in soil. The results of eld investigation data showed that even though 6 years the PCB concentrations in two elds were far from reaching uniform. In addition, rice grown in the eld appeared somewhat contamination by PCBs, but it was not likely subjected to concentrating PCBs from contaminated soil signi cantly. It was shown that the PCB concentrations in rice samples were not directly proportional to their concentrations in soil. Principal component analysis was performed with the standardized relative abundance of PCBs in the samples. All these observations indicated that the pattern of PCBs in soil cannot be considered to re ect the original pollution source.

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