Selectivity of PEG/Salt Aqueous Two-Phase System Enhanced by Surfactant@MWCNT Composites.

Aqueous two-phase systems (ATPS) are considered a new type of green separation system, but their low selectivity to target molecules limits their practical application. In this study, we used surfactant@MWCNT as an adjuvant to improve the selectivity of PEG/(NH4)2SO4 ATPS. The surfactants used include Triton X-100 (TX-100), Tween 80, sodium dodecyl sulfate (SDS), sodium dodecyl benzenesulfonate (SDBS), and bis(2-ethylhexyl)sulfosuccinate sodium salt (AOT). Nine aromatic compounds, including syringic acid, vanillin, tryptophan, phenylalanine, tyrosine, mandelic acid, theophylline, theobromine, and cephalexin, were selected as model extracts. The results showed that the use of the surfactant@MWCNT composite as an adjuvant significantly improved the selectivity of the ATPS toward syringic acid among the nine extracts. Moreover, the selectivity of the ATPS for syringic acid with the TX-100/MWCNT composite as the adjuvant is better than that with the Tween 80/MWCNT composite as the adjuvant, followed by that with the anionic surfactant/MWCNT composite as the adjuvant. The enhanced selectivity of ATPS by the surfactant/MWCNT composite is ascribed to the spatial effect and the electrostatic and hydrophobic interactions between the extract and the surfactant adsorbed on the MWCNT.

Improvement effect of p-sulfonatocalix[4]arene on the performance of the PEG/salt aqueous two-phase system.

The PEG/salt aqueous two-phase system (ATPS) is the most common ATPS, but its application is still limited due to the restricted polarity difference between the two phases and the poor enhancement effect of adjuvants on ATPS performance so far. Unlike the adjuvants used so far, calixarenes can bind ions and molecules via multiple noncovalent interactions. In the present study, a water-soluble calixarene, p-sulfonatocalix[4]arene (SC[4]), was used for the first time as the adjuvant to improve the performance of the PEG 600/(NH4)2SO4 ATPS through multiple interactions. It is found that when the SC[4] and the SC[4]/imidazole ionic liquid ([Cnmim]Br) complex were used as the adjuvants, the formation of PEG 600/(NH4)2SO4 ATPS was enhanced, and the transfer of the extracts (including S-mandelic acid, L-tryptophan, and L-phenylalanine) into the PEG phase was promoted. Moreover, although the single [Cnmim]Br, a commonly used adjuvant, does not promote the migration of the target molecules into the polymer phase, the SC[4]/[Cnmim]Br complex is superior to SC[4] in enhancing the performance of the ATPS because the SC[4]/[Cnmim]Br aggregates enable more binding sites to combine with the extract. Besides, the partition coefficient of SC[4] in the PEG/trisodium citrate ATPS is much smaller than that in the PEG/(NH4)2SO4 ATPS, which is helpful for the recovery of extracts into the citrate phase.

Knockdown of SHP2 attenuated LPS-induced ferroptosis via downregulating ACSL4 expression in acute lung injury.

BACKGROUND: Acute lung injury (ALI) is a complex disease with a high mortality. Src homology 2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2) is a protein tyrosine phosphatase that participates in pathogenesis of multiple diseases. Nevertheless, the role of SHP2 in ALI remains unknown. METHODS: The in vivo and in vitro lipopolysaccharide (LPS)-induced ALI models were successfully established. The histopathological changes were evaluated by hematoxylin and eosin staining. The vascular permeability of lungs was assessed by Evans blue assay. The expression of ACSL4 and SHP2 was detected by western blot and qRT-PCR assay. The lactate dehydrogenase (LDH) activity, malondialdehyde (MDA), iron, and glutathione (GSH) levels were measured by commercial kits. RESULTS: The SHP2 was upregulated in LPS-induced ALI mice and LPS-stimulated MLE-12 cells. In loss-of function experiment, the knockdown of SHP2 attenuated LPS-induced lung injury, microvessels damage, pulmonary edema, and increase of lung vascular permeability in vivo. Mechanically, shSHP2-rescued LPS induced increase in LDH activity, MDA, and iron levels, and decrease in GSH levels, as well as the accumulation of reactive oxygen species in vivo and in vitro, leading to an alleviation of LPS-induced ferroptosis. Notably, shSHP2 reduced the expression of Acyl-CoA synthetase long-chain 4 (ACSL4). In the rescued experiments, overexpression of ACSL4 abolished the shSHP2-induced reduction of LDH activity, MDA, and iron levels, and increase in GSH levels, thereby aggravating the LPS-induced ferroptosis. CONCLUSION: These findings concluded that the knockdown of SHP2 attenuated LPS-induced ferroptosis via downregulation of ACSL4 expression in ALI, providing a novel sight for ALI treatment.

Experimentally and Theoretically Revealing the Co-Doping Effects of Ce-Sr in Gd2Zr2O7.

To safely dispose radioactive waste (including, e.g., thorium and radiostrontium), Ce4+ and Sr2+ were chosen as simulated surrogates of α and ß waste and were introduced into the Gd3+ site in Gd2Zr2O7 to maintain the average cationic radius and to compensate for charge. A series of Gd2-xSrx/2Cex/2Zr2O7 (0.00 ≤ x ≤ 0.25) compounds were examined by experimental and theoretical calculations to investigate the co-doping effects of α and ß waste in a Gd2Zr2O7-based matrix. The effects of Ce4+ and Sr2+ content on the phase, unit cell parameters, active modes, mechanical property, and microstructure were studied systematically. Moreover, the limit of incorporation of Ce4+ and Sr2+ in Gd2Zr2O7 pyrochlore and the lattice parameters were also calculated through virtual crystal approximation theory, and the results were found to well agree with experimental results.

Employment and Mental Health of the Chinese Elderly: Evidence from CHARLS 2018.

Improving the mental health of the elderly has become an important strategic goal of healthy aging, among which employment is regarded as an essential factor for the mental health of the elderly. This study adopted ordinary least squares, ordered logit, propensity score matching (PSM), and KHB mediation analysis to examine the influence and mechanism of employment on mental health in older Chinese adults using data from the China Health and Retirement Longitudinal Survey of 2018. The study found that employment positively impacts older adults' mental health in China. This promotive effect of employment was significant for more senior people aged up to 80 years old with lower educational backgrounds and rural household registration. In addition, individual annual income, the financial support provided to children, and support received from children significantly mediate the realization of employment improving older people's mental health. Our findings are expected to provide valuable insight into delayed retirement and active aging in China. Therefore, the government must play the role of support and advocacy to promote employment and safeguard the well-being of older adults.