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As an eco‐friendly material, PLA was a desirable alternative to polyethylene and polypropylene films due to its biodegradability. The preferable melt strength of PLA‐based materials was a key factor in ensuring its processing using extrusion blow. This paper focuses on the influence of interchain force and/or chain entanglement on the melt strength and ductility of PLA‐based materials in recent years. In addition, the preparation of PLA‐based materials via physical blending or reactive processing was also summarized. The blending of PLA with a flexible heteropolymer, driven by the interchain force and/or chain entanglements, were characterized as a practicable method for toughening PLA‐based materials. Also, the restructuring of PLA chains, by branching based on chain entanglement, was suitable for increasing chain entanglements in PLA matrix, yielding satisfactory melt strength and ductility. This review aims to elucidate the relationship between interchain forces and/or entanglement with the melt strength and ductility of PLA‐based materials. An essential and systematic understanding of the tailoring melt strength and rheological properties of PLA by interchain forces and/or entanglement was apt to improve and perfect the processing technology of the extrusion blow, and consequently improve the tensile strength and toughness of PLA films. [ABSTRACT FROM AUTHOR]

Lanthanum complex with curcumin (La L2)/Ca‐Zn composite stabilizer was prepared using La L2 and Ca‐Zn stabilizer, in which Ca‐Zn stabilizer was obtained from calcium stearate and zinc stearate at their mass ratio of 5:1. The rheological properties and dynamic thermal stability of polyvinyl chloride (PVC) stabilized by La L2/Ca‐Zn composite stabilizers were estimated through a torque rheometer. The degraded fragments obtained from the torque experiments were measured by Fourier‐transform infrared spectroscopy (FTIR) and ultraviolet–visible (UV‐vis) spectroscopy. La L2 had an effective synergistic effect with Ca‐Zn stabilizer. Compared with La L2, La L2/Ca‐Zn composite stabilizer could more significantly improve the rheological properties and dynamic thermal stability of PVC. An optimal synergistic effect could be observed when the mass ratio of La L2 with Ca‐Zn stabilizer was about 8:2, in which the plasticizing torque and equilibrium torque of PVC was 33.3 N m and 22.5 N m, respectively, and its dynamic thermal stabilizing time was 25.1 min. The possible thermal stability mechanism of La L2/Ca‐Zn composite stabilizer for PVC was suggested based on the evaluation of FTIR spectroscopy and UV‐vis spectroscopy. [ABSTRACT FROM AUTHOR]

The purpose of this study was to figure out the dysregulation of miR-942-5p in melanoma and its role in melanoma pathogenesis. Quantitative real-time PCR (qRT-PCR) assay was used to determine the change of RNA expression. Protein expression was examined by Western blotting. miRNA target was validated through TargetScan and luciferase assay. Cell migration and invasion were detected by wound healing and transwell assay, respectively. Results of qRT-PCR manifested miR-942-5p were upregulated in melanoma cell. High expression of miR-942-5p in melanoma patients presented a poor prognosis. Upregulation of miR-942-5p accelerated cell proliferation, migration, and invasion in melanoma cells. Cell apoptosis was inhibited by miR-942-5p mimics. Suppression of miR-942-5p by its inhibitor showed the opposite effects in melanoma cells. TargetScan and luciferase assay showed that miR-942-5p directly targeted to the 3′-untranslated region (3′-UTR) of DKK3. Overexpression of DKK3 inhibited GSK-3β phosphorylation and reduced the expression of β-catenin in both cytoplasm and nucleus, which were induced by miR-942-5p mimics leading to the activation of Wnt/β-catenin pathway. Upregulation of miR-942-5p was observed in melanoma cells and tissues and significantly associated with a poor prognosis. Though targeting 3′-UTR of DKK3, miR-942-5p could activate Wnt/β-catenin pathway, resulting in melanoma cell proliferation, migration, and invasion, which promoted the development of melanoma. These results showed that miR-942-5p might be a diagnosis and prognosis biomarker in melanoma. [ABSTRACT FROM AUTHOR]