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Objective To investigate the method for establishing an immortalized mouse corneal epithelial cell line, and to identify the stability of its phenotype. Methods Primary mouse corneal epithelial cells were extracted and transfected with Simian Vacuolating Virus 40 Large T Antigen (SV40-LT) lentivirus to establish an immortalized cell line. HE staining and immunofluorescent staining were used to identify the phenotypes and markers (K12, Pax6, Ki-67) of corneal epithelium. Primary cor-neal epithelial cells were extracted to identify K14 protein in corneal epithelial cell layer, and bright field observation was performed to evaluate cell morphological characteristics. Several markers (K12, Pax6, Ki-67, ABCG2, K14) were identified for P1 and P8 cells after transfection. Crystal violet staining was used to observe the colony-formation ability of P1 and P8 cells after transfection. Results Mouse corneal epithelium was stained positive for K12, Pax6 and Ki-67, while the P1 and P8 generations of mouse cor-neal epithelial cells were stained positive for K12, Pax6, Ki-67, K14, and ABCG2; there were no significant differences in the positive rates of the above markers (P>0.05). There was no significant difference in colony-formation ability between P1 and P8 cells (P>0.05). Conclusion The immortalized mouse corneal epithelial cell line is successfully established by transfection with SV40-LT lentivirus, which has stable phenotype and proliferation.

Polylactide (PLA) was melt blended with poly(1,2-propylene glycol adipate) (PPA) in a Thermo-Haake mixer. Thermal, mechanical, and rheological properties of the blends were investigated by means of differential scanning calorimetry, dynamic mechanical analysis, tensile test, and small amplitude oscillatory shear rheometry. PPA lowered the glass transition temperature and increased the ability of PLA to cold crystallization. With the increase in PPA content (5-25 wt%), the blends showed decreased tensile strength and Young's modulus; however, impact strength and elongation-at-break along were dramatically increased due to the plastic deformation. Morphological results of PLA/PPA blends showed that PPA was good compatible with PLA. The plasticization effect of PPA was also manifested by the lowering of dynamic storage modulus and viscosity in the melt state of the blends compared with neat PLA. POLYM. ENG. SCI., 53:112-118, 2013. © 2012 Society of Plastics Engineers, INTRODUCTION The growing global concern over persistent plastic waste has generated much interest in biodegradable polymers for everyday use. Recent developments in the manufacturing of the polymer economically from agricultural [...]

Polylactide (PLA) is an attractive candidate for replacing petrochemical polymers because it is biodegradable. In this study, a specific PLA 2002D was melt-mixed with a new plasticizer: glycerol monostearate (GMS). The PLA/GMS blends with different ratios were analyzed by dynamic mechanical analysis and differential scanning calorimetry. Although a slightly phase separation can be seen in DSC curves, the SEM micrographs of the impact fracture surfaces of PLA/GMS blends had a relatively good separation and this phenomenon was in good agreement with their higher impact strength. The result showed that the adding of GMS has enhanced the flexibility of PLA/GMS blends as compared to neat PLA. The relationship between complex viscosity and angular frequency of the PLA/GMS blends exhibits that the melt viscosity substantially lower than that of neat PLA. For example, at 10 rad/s, the melt viscosity of PLA/GMS (85/15) was reduced by about 7.2% compared to that of neat PLA. The impact strength was changed from 4.7 KJ/m2 for neat PLA to 48.2 KJ/m2 for 70/30 PLA/GMS blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Purpose: Abnormalities in aquaporins are implicated in the pathological progression of dry eye syndrome. Retinoic acid (RA) regulates cellular proliferation, differentiation, and apoptosis in the cornea, thereby being associated with dry eye disease (DED). The objective of this study is to explore the underlying mechanisms responsible for RA metabolic abnormalities in corneas lacking aquaporin 5 (AQP5)., Methods: Dry eye (DE) models were induced via subcutaneous scopolamine hydrobromide. Aqp5 knockout (Aqp5-/-) mice and DE mice were utilized to assess corneal epithelial alterations. Tear secretion, goblet cell counts, and corneal punctate defects were evaluated. The impact of Aqp5 on RA-related enzymes and receptors was investigated using pharmacological RA or SR (A JunB inhibitor), a transcription factor JunB inhibitor, treatment in mouse corneal epithelial cells (CECs), or human corneal epithelial cells (HCECs). The HCECs and NaCl-treated HCECs underwent quantitative real-time PCR (qRT-PCR), immunofluorescent, Western blot, and TUNEL assays. The regulation of transcription factor JunB on Aldh1a1 was explored via ChIP-PCR., Results: Aqp5 and Aldh1a1 were reduced in both CECs of DE mice and NaCl-induced HCECs. Aqp5-/- mice exhibited DE phenotype and reduced Aldh1a1. RA treatment reduced apoptosis, promoted proliferation, and improved the DE phenotype in Aqp5-/- mice. JunB enrichment in the Aldh1a1 promoter was identified by ChIP-PCR. SR significantly increased Aldh1a1 expression, Ki67, and ΔNp63-positive cells, and decreased TUNEL-positive cells in CECs and HCECs., Conclusions: Our findings demonstrated the downregulation of Aqp5 expression and aberrant RA metabolism in DE conditions. Knockout of Aqp5 resulted in reduced production of RA through activation of JunB, subsequently leading to the manifestation of DE symptoms.