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• Ginseng resist red blood cell oxidative stress via their "Qi-invigorating" effect. • Ginseng total saponins promote red blood cell membrane protein expression. • Ginseng total saponins improve energy metabolism of red blood cell. • Ginseng total saponins restore Band 3 protein function by inhibiting tyrosine phosphorylation. • Ginseng total saponins restore glycolysis by improving Band 3 protein function. Oxidative stress is the main cause of many diseases, but because of its complex pathogenic factors, there is no clear method for treating it. Ginseng total saponin (GTS) an important active ingredients in Panax ginseng C.A. Mey (PG) and has potential therapeutic ability for oxidative stress due to various causes. However, the molecular mechanism of GTS in the treating oxidative stress damage in red blood cells (RBCs) is still unclear. This study aimed to examine the protective effect of GTS on RBCs under oxidative stress damage and to determine its potential mechanism. The oxidative stress models of rat RBCs induced by hydrogen peroxide (H 2 O 2) and exhaustive swimming in vivo and in vitro was used. We determined the cell morphology, oxygen carrying capacity, apoptosis, antioxidant capacity, and energy metabolism of RBCs. The effect of tyrosine phosphorylation (pTyr) of Band 3 protein on RBCs glycolysis was also examined. GTS reduced the hemolysis of RBCs induced by H 2 O 2 at the lowest concentration. Moreover, GTS effectively improved the morphology, enhanced the oxygen carrying capacity, and increased antioxidant enzyme activity, adenosine triphosphate (ATP) levels, and adenosine triphosphatase (ATPase) activity in RBCs. GTS also promoted the expression of membrane proteins in RBCs, inhibited pTyr of Band 3 protein, and further improved glycolysis, restoring the morphological structure and physiological function of RBCs. This study shows, that GTS can protect RBCs from oxidative stress damage by improving RBCs morphology and physiological function. Changes in pTyr expression and its related pTyr regulatory enzymes before and after GTS treatment suggest that Band 3 protein is the main target of GTS in the treating endogenous and exogenous oxidative stress. Moreover, GTS can enhance the glycolytic ability of RBCs by inhibiting pTyr of Band 3 protein, thereby restoring the function of RBCs. [ABSTRACT FROM AUTHOR]

In the face of conflicting land-resource supply and demand, land-use efficiency is critical for sustainable urbanization. In this study, we unified the consistent boundaries of land, population, and economic development, identified urban expansion patterns (infilling, edge expansion and leapfrogging), and precisely estimated urban land-use efficiency (ULUE) in 260 Chinese cities from the perspective of dynamic expansion during 2000–2015. With the consideration of the dynamics of outward expansion and internal development of urban land, the results showed that China's main expansion pattern gradually shifted from edge expansion with lower ULUEs to infilling with higher ULUEs. Over the 15-year period, ULUEs in all expansion areas increased from 0.065–0.18 to 0.093–0.31. Inequity remained significant in terms of expansion patterns, built-up layers, regions and urban sizes. ULUE increased more quickly in the super-large cities of the central and western regions, whereas it increased more slowly in the northeast and even decreased in expansion built-up area formed during 2005–2010 (EBUA (2005–2010)). Importantly, ULUE decreased in most cities with edge expansion. Based on the findings, we concluded that the urbanization of China was progressing toward sustainability but still had room for improvement, and we suggested that policymakers should pay more attention to the complex, systemic nature of urban development. • Urban land, population, and economic boundaries were unified. • Inequity remained significant in terms of expansion patterns, built-up layers, regions and urban sizes. • China' s main expansion pattern gradually shifted from lower-efficiency edge expansion to higher-efficiency infilling. • Urban expansion land had limited ULUE development potential. [ABSTRACT FROM AUTHOR]

Interaction mechanisms of tetracycline (TC, as a typical antibiotic) on polystyrene microsphere (PSs, as a typical nanoplastic) were conducted by the batch, spectroscopic and theoretical techniques. The batch results showed that Na+ and K+ had no obvious effects on TC adsorption towards PSs, whereas Mg2+ significantly inhibited TC adsorption at pH > 5.0 due to its induced aggregations of PSs. The maximum TC adsorption capacity of PSs in the presence of humic acid (50.99 mg/g) was higher than that of PSs (44.77 mg/g) at pH 6.0. The highly effective adsorption was attributed to electrostatic attraction, π-π interaction and hydrophobic effect, which was determined by FT-IR and XPS analysis. According to DFT (density functional theory) calculations, the adsorption energy of TC/TC+ on PSs (1.52 eV) was significantly higher than that of negative TC− (0.57 eV), whereas minimum distance of TC on PSs (3.684 Å) was shorter than that of TC− on PSs (3.988 Å). The results of theoretical calculations indicated that TC was more preferably adsorbed on PSs with more stable configuration compared to TC−. These findings indicated that PSs can be used as a promising adsorbent for immobilization and pre-concentration of TC from aqueous solutions. Image 1 • TC sorption on PSs were electrostatic attraction, π-π interaction, hydrophobicity. • Mg2+ inhibited TC sorption at pH > 5.0 due to the induced aggregations of PSs. • HA enhanced TC sorption was due to the increased dispersion of PSs. • Highsorption energy of TC on PSs was demonstrated by DFT calculations. Investigations of antibiotics removal on nanoplastics in waste control by waste. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is one of the world's most deadly infectious diseases resulting in nearly 1.3 million deaths annually and infecting nearly one-quarter of the population. para -Aminosalicylic acid (PAS), an important second-line agent for treating drug-resistant Mycobacterium tuberculosis , has moderate bioavailability and rapid clearance that necessitate high daily doses of up to 12 g per day, which in turn causes severe gastrointestinal disturbances presumably by disruption of gut microbiota and host epithelial cells. We first synthesized a series of alkyl, acyloxy and alkyloxycarbonyloxyalkyl ester prodrugs to increase the oral bioavailability and thereby prevent intestinal accumulation as well as undesirable bioactivation by the gut microbiome to non-natural folate species that exhibit cytotoxicity. The pivoxyl prodrug of PAS was superior to all of the prodrugs examined and showed nearly quantitative absorption. While the conceptually simple prodrug approach improved the oral bioavailability of PAS, it did not address the intrinsic rapid clearance of PAS mediated by N-acetyltransferase-1 (NAT-1). Thus, we next modified the PAS scaffold to reduce NAT-1 catalyzed inactivation by introduction of groups to sterically block N -acetylation and fluorination of the aryl ring of PAS to attenuate N -acetylation by electronically deactivating the para -amino group. Among the mono-fluorinated analogs prepared, 5-fluoro-PAS, exhibited the best activity and an 11-fold decreased rate of inactivation by NAT-1 that translated to a 5-fold improved exposure as measured by area-under-the-curve (AUC) following oral dosing to CD-1 mice. The pivoxyl prodrug and fluorination at the 5-position of PAS address the primary limitations of PAS and have the potential to revitalize this second-line TB drug. [Display omitted] • p -Aminosalicylic acid (PAS), a potent anti-tubercular agent, has limiting oral bioavailability. • Prodrugs and structural analogs improve pharmacokinetic properties of drugs. • Pivoxyl PAS prodrug quantitatively improves oral bioavailability of PAS. • PAS analogs show a 5 to 430-fold improvement in oral bioavailability, but result in a loss of potency. • Increased exposures of 5-Fluoro PAS and N-Methyl PAS are due to poor substrate specificities towards N-acetyl transferase 1. [ABSTRACT FROM AUTHOR]