Moisture-Adaptive Contractile Biopolymer-Derived Fibers for Wound Healing Promotion.

The advancement in thermosensitive active hydrogels has opened promising opportunities to dynamic full-thickness skin wound healing. However, conventional hydrogels lack breathability to avoid wound infection and cannot adapt to wounds with different shapes due to the isotropic contraction. Herein, a moisture-adaptive fiber that rapidly absorbs wound tissue fluid and produces a large lengthwise contractile force during the drying process is reported. The incorporation of hydroxyl-rich silica nanoparticles in the sodium alginate/gelatin composite fiber greatly improves the hydrophilicity, toughness, and axial contraction performance of the fiber. This fiber exhibits a dynamic contractile behavior as a function of humidity, generating ≈15% maximum contraction strain or ≈24 MPa maximum isometric contractile stress. The textile knitted by the fibers features excellent breathability and generates adaptive contraction in the target direction during the natural desorption of tissue fluid from the wounds. In vivo animal experiments further demonstrate the advantages of the textiles over traditional dressings in accelerating wound healing.

The hydrochar activation and biocrude upgrading from hydrothermal treatment of lignocellulosic biomass.

The production of hydrochar and biocrude from hydrothermal treatment of lignocellulosic biomass is getting increasing attention, but the quality of hydrochar and biocrude need further improvement before utilization. Many attempts have been carried out on the hydrochar activation and biocrude upgrading. However, different methods play different roles on the property of hydrochar and biocrude, this topic received scant attention in recent review papers. Therefore, the influence of different activation methods on hydrochar property, and the potential application of hydrochar were summarized in this study. Meanwhile, the research progress on biocrude upgrading is reported. Besides, the techno-economic analysis of hydrochar and biocrude from hydrothermal treatment of lignocellulosic biomass are also discussed. Finally, the research needs and future directions on hydrochar activation and biocrude upgrading were proposed. This paper could provide insights for further studies on the utilization of hydrochar and biocrude.

Tissue distribution of polystyrene nanoplastics in mice and their entry, transport, and cytotoxicity to GES-1 cells.

With the widespread use of plastics and nanotechnology products, nanoplastics (NPs) have become a potential threat to human health. It is of great practical significance to study and evaluate the distribution of NPs in mice as mammal models and their entry, transport, and cytotoxicity in human cell lines. In this study, we detected the tissue distribution of fluorescent polystyrene nanoplastics (PS-NPs) in mice and assessed their endocytosis, transport pathways, and cytotoxic effects in GES-1 cells. We found that PS-NPs were clearly visible in gastric, intestine, and liver tissues of mice and in GES-1 cells treated with PS-NPs. Entry of PS-NPs into GES-1 cells decreased with the inhibition of caveolae-mediated endocytosis (nystatin), clathrin-mediated endocytosis (chlorpromazine HCl), micropinocytosis (ethyl-isopropyl amiloride), RhoA (CCG-1423), and F-actin polymerization (lantrunculin A). Rac1 inhibitors (NSC 23766) had no significant effect on PS-NPs entering GES-1 cells. F-actin levels significantly decreased in CCG-1423-pretreated GES-1 cells exposed to PS-NPs. GES-1 cell ultrastructural features indicated that internalized PS-NPs can be encapsulated in vesicles, autophagosomes, lysosomes, and lysosomal residues. RhoA, F-actin, RAB7, and LAMP1 levels in PS-NPs-treated GES-1 cells were remarkably up-regulated and the Rab5 level was significantly down-regulated compared to levels in untreated cells. PS-NPs treatment decreased cell proliferation rates and increased cell apoptosis. The formation of autophagosomes and autolysosomes and levels of LC3II increased with the length of PS-NPs treatment. The results indicated that cells regulated endocytosis in response to PS-NPs through the RhoA/F-actin signaling pathway and internalized PS-NPs in the cytoplasm, autophagosomes, or lysosomes produced cytotoxicity. These results illustrate the potential threat of NPs pollution to human health.

Synergistic effects on cellulose and lignite co-pyrolysis and co-liquefaction.

The synergistic effects of lignite and cellulose co-pyrolysis and co-liquefaction were investigated. The optimal liquid fuel yield of co-pyrolysis was 34.72% at a reaction temperature of 550 °C, with a holding time of 30 min, whereas that of co-liquefaction was 39.26% at a reaction temperature of 340 °C, with a holding time of 30 min, an ethanol content of 60% in sub-/supercritical ethanol-water, and a liquid-material ratio of 10:1 (ml/g). Liquid fuel obtained under the best conditions was performed using Fourier transform infrared (FTIR) spectroscopy and gas chromatograph-mass spectrometer (GC-MS). The results of liquid fuel characterization showed that a synergy in co-pyrolysis and co-liquefaction, and the synergy of co-liquefaction was better than that of co-pyrolysis. The reaction mechanism revealed that the presence of the electron-supplying groups generated from cellulose cracking and ethanol reduced the bond energy in the macromolecular structure of lignite and promoted the thermal conversion of lignite.

Polyethylene microplastics affect the distribution of gut microbiota and inflammation development in mice.

Environmental pollution caused by plastics has become a public health problem. However, the effect of microplastics on gut microbiota, inflammation development and their underlying mechanisms are not well characterized. In the present study, we assessed the effect of exposure to different amounts of polyethylene microplastics (6, 60, and 600 µg/day for 5 consecutive weeks) in a C57BL/6 mice model. Treatment with a high concentration of microplastics increased the numbers of gut microbial species, bacterial abundance, and flora diversity. Feeding groups showed a significant increase in Staphylococcus abundance alongside a significant decrease in Parabacteroides abundance, as compared to the blank (untreated) group. In addition, serum levels of interleukin-1α in all feeding groups were significantly greater than that in the blank group. Of note, treatment with microplastics decreased the percentage of Th17 and Treg cells among CD4+ cells, while no significant difference was observed between the blank and treatment groups with respect to the Th17/Treg cell ratio. The intestine (colon and duodenum) of mice fed high-concentration microplastics showed obvious inflammation and higher TLR4, AP-1, and IRF5 expression. Thus, polyethylene microplastics can induce intestinal dysbacteriosis and inflammation, which provides a theoretical basis for the prevention and treatment of microplastics-related diseases.

Study on pyrolytic kinetics and behavior: The co-pyrolysis of microalgae and polypropylene.

In the current work, the co-pyrolysis kinetics of Dunaliella tertiolecta and PP were investigated via TGA, while TG-FTIR and TG-MS were used for the analysis of gas-phase components and volatiles transition. The TGA results show that PP with certain small particle size accelerates the pyrolysis process of the microalgae, while the existence of D. tertiolecta delayed that of PP. This significant interaction achieves maximum when mass ratio of PP and D. tertiolecta is 6:4. The activation energy estimated from FWO kinetic model also supports this interaction. The TG-FTIR and TG-MS results show that a significant decrease of CO2 occurs at PP and D. tertiolecta mass ratio of 6:4, indicating that small molecules (such as radicals) released by PP might react with CO2 produced by D. tertiolecta or carbonyl groups in the microalgae.