Furfurylamine (FLA) is known as an important biobased product for the production of food additives, fuel additives, polymers, fibers, perfumes, and pharmaceuticals. In this study, recombinant Escherichia coli CV-PRSFDuet whole cells harboring transaminase were used for converting biomass-derived furfural into furfurylamine at pH 7.5 and 35 °C using l-alanine as the amine donor. Whole-cell-catalyzed conversion of 300 mM furfural gave 84.0% yield of furfurylamine with 100% selectivity. 90.3 mM furfural was obtained from the alkali pretreatment of dewaxed corncob (75 g/L) at 170 °C for 0.5 h with an acidified Sn-ZRD catalyst (3.6 wt %, pH 1.0) in the aqueous media, which could be biconverted into furfurylamine at 76.3% yield (0.267 g furfurylamine/g xylan in corncob) within 8.5 h in the presence of 10 mol l-alanine/mol furfural. Clearly, chemoenzymatic synthesis of furfurylamine from corncob could be conducted in a one-pot manner. Finally, an efficient recycling and reuse of the Sn-ZRD catalyst and immobilized whole cell biocatalyst were developed for the chemoenzymatic synthesis of FLA from corncob in the one-pot reaction system. In summary, an initial approach for high-value utilization of biomass into FLA and its derivatives was successfully provided under relatively mild performance conditions.

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This study assessed the role of epithelial-mesenchymal interconversions and the regulatory functions of the ZEB family during the development and progression of ovarian cancer. E-cadherin, vimentin, ZEB1 and ZEB2 were analyzed using immunohistochemistry in a series of ovarian tissues that included normal tissue, benign tumors, borderline tumors, malignant tumors and metastatic lesions. The correlation between E-cadherin and ZEB was analyzed. We also analyzed the association between the expression of the four factors and clinicopathological features in ovarian cancer. The results revealed that E-cadherin was weakly positive in normal ovarian epithelium. Cytoplasmic E-cadherin was significantly increased in benign tumors (P<0.01) and further increased in borderline tumors and ovarian cancers. However, cytoplasmic E-cadherin was markedly reduced in metastatic lesions (P<0.01). Membranous E-cadherin was increased in benign tumors, but decreased progressively in borderline, malignant and metastatic tumor tissues (P<0.05). The expression profile of vimentin was opposite to that of membranous E-cadherin. Membranous E-cadherin was negatively correlated with ZEB2 expression (r=-0.514). Additionally, cytoplasmic E-cadherin, ZEB1 and ZEB2 were associated with the FIGO stage of ovarian cancer. ZEB1 was also correlated with ascitic fluid volume. Our results suggest that epithelial-mesenchymal interconversions are dynamically regulated during the development and progression of ovarian tumors. ZEB2, but not ZEB1, may regulate the expression of membranous E-cadherin during these processes.

To evaluate the influence of low temperatures on the proliferation of neural stem cells (NSCs) and the regulation of their signaling pathways after brain trauma, we examined changes in the expression levels of specific miRNAs and their target genes. We also evaluated NSC proliferation in the hippocampus after brain trauma under low-temperature conditions. We found that the expression profile of miRNAs in the hippocampus after trauma changed at both normal and low temperatures, and the expression of miR-34a decreased significantly lower in rats exposed to low temperatures. There was significant proliferation of endogenous NSCs in the hippocampus after brain trauma at both temperatures, but NSC proliferation was slower at low temperatures. In addition, the expression of Notch1 significantly increased in the hippocampus after brain trauma at both temperatures. However, at low temperatures, the degree of up-regulation of Notch signaling molecules was significantly lower. We conclude that low-temperature environments can inhibit the proliferation of endogenous NSCs in the hippocampus, possibly by alleviating the effects of miR-34a down-regulation and Notch signaling up-regulation induced by traumatic brain injury.

This paper reviewed the research progress in China on the durability, acid and alkali corrosion resistances, thermal insulation, sound insulation, and hygroscopic properties of basalt fibers (BFs) as well as the physicochemical and mechanical properties of BF-reinforced resin composites. The acidity coefficient and pH value of BFs and glass fibers (GFs) were tested, which showed that BFs had better chemical stability. Scanning electron microscopy observations showed that the acid corrosion of BFs gradually occurred from the outside to the inside, whereas the alkali corrosion of BFs occurred nearly simultaneously both inside and outside. Moreover, the reasons for these results were analyzed from a chemical reaction perspective. BFs met the thermal conductivity and sound absorption coefficient requirements of building thermal insulation and sound absorption materials. The hygroscopicity of BFs was 1/8–1/6 that of GFs, and BFs also had a smaller dielectric loss angle. Tests confirmed that BFRC exhibited great high-temperature resistance. As the short BF content increased, the flexural strength, splitting tensile strength and impermeability of BFRC significantly improved, and an optimal fiber length and content were proposed. A comparison showed that the mechanical properties of BF-reinforced resin were generally better than those of GF-reinforced resin. Finally, this review identified some concepts to be studied in this field and prospects for possible future research directions. [Formula: see text]