Poly(l-lactic acid-b-ethylene oxide-b-l-lactic acid) (PLLA-b-PEO-b-PLLA) triblock copolymers were synthesized by a ring-opening polymerization. PLLA and PEO sequentially crystallized by slowly cooling (−2 °C/min) from the melt. In the resultant spherulitic morphology, the retardation of polarized light was additive, and the sign of the spherulite (negative) was preserved when the PEO crystallized within the framework established by the PLLA crystals. Homopolymer blends of PLLA and PEO having the same composition as the block copolymer showed similar optical behavior. However, the change in the optical retardation upon crystallization of the PEO was much greater for the triblock copolymer than for the blend. Upon heating, the small-angle X-ray scattering from both the triblock copolymer and homopolymer mixture showed a stepwise increase in the long period at ∼60 °C, i.e., when the PEO crystals melted. For comparable volume fractions (φPLLA = 0.57), the increase in long period was greater for the triblock copolymer than for the blend. Wide-angle X-ray diffraction studies on shear aligned triblock copolymers indicate that the PLLA and PEO crystals adopt the same average orientation; though, in the case of the copolymer, the orientation is more strongly coupled.

Enhanced endothelialization of tissue-engineered blood vessels is essential for vascular regeneration and function of engineered vessels. In this study, mussel-inspired surface chemistry of polydopamine (pDA) coatings are applied to functionalize decellularized vein matrix (DVM) with extracellular matrix-derived cell adhesion peptides (RGD and YIGSR). DVMs engineered with pDA-peptides enhance focal adhesion, metabolic activity, and endothelial differentiation of human endothelial progenitor cells (EPCs) derived from cord blood and embryonic stem cells compared with EPCs on non-coated or pDA-coated DVMs. These results indicate that pDA-peptide functionalization may contribute to enhanced, rapid endothelialization of DVM surfaces by promoting adhesion, proliferation, and differentiation of circulating EPCs. Ultimately, this approach may be useful for improving in vivo patency and function of decellularized matrix-based blood vessels.

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The purpose of this study was to assess the relationship between vitamin D receptor gene (VDR) expression and prognostic factors in papillary thyroid cancer (PTC). mRNA sequencing and somatic mutation data from The Cancer Genome Atlas (TCGA) were analyzed. VDR mRNA expression was compared to clinicopathologic variables by linear regression. Tree-based classification was applied to find cutoff and patients were split into low and high VDR group. Logistic regression, Kaplan–Meier analysis, differentially expressed gene (DEG) test and pathway analysis were performed to assess the differences between two VDR groups. VDR mRNA expression was elevated in PTC than that in normal thyroid tissue. VDR expressions were high in classic and tall-cell variant PTC and lateral neck node metastasis was present. High VDR group was also associated with classic and tall cell subtype, AJCC stage IV and lower recurrence-free survival. DEG test reveals that 545 genes were upregulated in high VDR group. Thyroid cancer-related pathways were enriched in high VDR group in pathway analyses. VDR mRNA overexpression was correlated with worse prognostic factors such as subtypes of papillary thyroid carcinoma that are known to be worse prognosis, lateral neck node metastasis, advanced stage and recurrence-free survival.

The polymer-stabilized vertically aligned (PS-VA) liquid crystal display (LCD) driving mode has high potential for manufacturing low power consuming displays due to the higher transmittance and fast response as compared with the existing patterned vertically aligned and multi-domain vertically aligned modes. In this paper we have investigated the reaction mechanisms of monomer–liquid crystal blends to form a surface pre-tilt angle of liquid crystal in vertical alignment LCD associated with a fishbone electrode structure. The observed sizes of polymer bumps formed on the substrates were found to be dependent on the exposed UV wavelength and were almost equal in both top and bottom substrates. When a large UV wavelength was used, the phase separation mechanism of monomer in PS-VA mode was found nearly isotropic rather than anisotropic in contrast to the previous studies.

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