The Effect of Platelet-Rich Plasma on the Osteoblastic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stromal Cells.

BACKGROUND: Mesenchymal stem cells (MSCs) are cell populations that have the potential to proliferate and differentiate. The process of stem cell differentiation from pluripotent cells to bone cells requires general changes in their pattern of gene expression, the most well-known of which are changes in miRNA-dependent settings. Platelet-enriched plasma (PRP) releases growth factors that are mitogenic to mesenchymal cells and can accelerate the process of osteogenic differentiation. The aim of this study was to investigate the effect of PRP on the expression changes of Let-7a, mir-27a, mir-31, mir-30c, mir-21, and mir-106a during osteogenic differentiation. METHODS: MSCs were isolated from adipose tissue after abdominoplasty and evaluated by flow cytometry. The ef-fect of PRP (10%) on the process of osteogenic differentiation was determined by measuring the expression of Let-7a, mir-27a, mir-31, mir-30c, mir-21, and mir-106a using the real-time polymerase chain reaction (PCR) technique. RESULTS: The increase in Let-7a expression was significant on the 14th day compared to the 3rd day. mir-27a expression rose significantly on the 3rd day. The expression of mir-30 exhibited a significant increase on the 14th day. mir-21 expression was significantly enhanced on the 3rd day and was downregulated on the 14th day. mir-106a expression showed a significant decreasing tendency between days 3 and 14 in a time-dependent pattern. CONCLUSIONS: These findings indicate that PRP probably accelerates the process of differentiation into bone. PRP, as a biological catalyst, showed a clear and distinct impact on the miRNAs regulating bone differentiation of human mesenchymal cells.

Assessing the performance of sand filter basins in treating urban stormwater runoff.

This study has assessed the efficiency of sand filter basins in treating urban stormwater runoff by analyzing available data in the literature, the International Stormwater BMP Database, and data collected in a sand filter basin located in the main campus of the University of Texas at San Antonio (UTSA). Ten storm events were monitored starting in March 2016 until February 2017. Total suspended solids, volatile suspended solids, nitrate, ortho-phosphate, copper, zinc, lead, pH, and conductivity were measured in the inlet and the outlet of the basin. Statistical analysis, including linear regression modeling, scatter plotting, and non-parametric testing, using data from the literature and the International Stormwater BMP Database was performed. The sand filter basin removed, on average, 94% and 86% of TSS and VSS, respectively. Such high removal rates were not observed for other constituents, with exception of lead (79%) that already showed a low mean concentration in the inlet of the basin (41.47 ± 27.41 µg/L). Nitrate and ortho-phosphate mean concentrations were not significantly different in the outlet than inlet. The basin effluent concentration of zinc was higher than acceptable stormwater benchmarks defined by EPA. The results indicated that the monitored sand filter basin met its primarily design criteria, which is TSS removal by at least 80% of mass. Better stormwater treatment practices, however, are needed to remove other pollutants more efficiently, in particular, because this area is located on top of the recharge zone of the Edwards Aquifer, a major source of water supply for the region.