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The aim of this study was to explore the function of Pentraxin-3 (PTX3) in cell viability, pyroptosis, inflammation, osteogenic differentiation, and oxidative stress of lipopolysaccharide (LPS)-stimulated human periodontal ligament stem cells (hPDLSCs). In the study, hPDLSCs were stimulated by LPS from Porphyromonas gingivalis to establish an in vitro inflammatory cellular model. Protein expression was measured using Western blotting. mRNA levels were evaluated by qRT-PCR. Cell viability, inflammatory cytokine production, and caspase-1 activity was measured with commercially available kits. Oxidative stress was assessed by examining reactive oxygen species and nitric oxide production. We found that PTX3 was upregulated in LPS-stimulated hPDLSCs. PTX3 overexpression aggravated LPS-induced cell viability loss, inflammatory cytokine production, and oxidative stress, as well as suppressed the osteogenic differentiation in hPDLSCs, while silencing PTX3 had the opposite effects. Further, PTX3 overexpression promoted NOD-like receptor family, pyrin domain containing protein 3 (NLRP3) inflammasome overactivation and pyroptosis, evidenced by increased protein levels of NLRP3, cleaved-caspase-1, apoptosis-associated speck-like protein (ASC), and N-terminal gasdermin D (GSDMD-N). Inhibition of NLRP3 inflammasome and/or caspase-1 partially attenuated the effects of PTX3 on LPS-stimulated hPDLSCs. This study indicated that PTX3 promotes LPS-induced pyroptosis and inflammation in hPDLSCs through activation of the caspase-1-dependent NLRP3 inflammasome.

The retrogradation properties of lotus seed starch (LS) blended with the hydrocolloids arabic gum (AG), carrageenan (CG), guar gum (GG), and xanthan (XN) were investigated undergoing an autoclaving-cooling treatment, a model for starch retrogradation acceleration. Compared with LS alone, LS-AG showed the increases in syneresis, tan δ (more solid-like behavior), bound water content and immobile water content, molecular weight, the intensity at 480 cm-1 in Raman spectra and the ratio of absorbance 1047 cm-1 /1022 cm-1 (R1047/1022 ) in FT-IR spectra. The results suggested that the addition of AG tended to promote the starch retrogradation, which was related to the increased molecular migration of free water, interactions of molecular starch chains, and the formation of ordered structures. The addition of CG, GG, or XN significantly decreased the syneresis, tan δ, the intensity at 480 cm-1 , and R1047/1022 values of LS, indicating the prevention of LS retrogradation. The effects of CG and XN on starch retrogradation mainly resulted from competition for water and the increased viscosity, as well as the coating effect on starch. The dominant viscosity of GG was the main factor that influenced starch retrogradation. These results showed not all hydrocolloids would retard starch retrogradation under autoclaving-cooling treatment, for which fine structures altered by different hydrocolloids were the key factors. PRACTICAL APPLICATION: Effects of hydrocolloids on the retrogradation of lotus seed starch were investigated undergoing an autoclaving-cooling treatment. The results will help guide the production and development of starchy foods having desirable properties by specific hydrocolloids during autoclaving-cooling process, especially to control starch retrogradation.

In this work, two fully novel finite difference schemes for two-dimensional time-fractional mixed diffusion and diffusion-wave equation (TFMDDWEs) are presented. Firstly, a Hermite and Newton quadratic interpolation polynomial have been used for time discretization and central quotient has used in spatial direction. The H2N2 finite difference is constructed. Secondly, in order to increase computational efficiency, the sum-of-exponential is used to approximate the kernel function in the fractional-order operator. The fast H2N2 finite difference is obtained. Thirdly, the stability and convergence of two schemes are studied by energy method. When the tolerance error \begin{document}$ \epsilon $\end{document} of fast algorithm is sufficiently small, it proves that both of difference schemes are of \begin{document}$ 3-\beta\; (1 order convergence in time and of second order convergence in space. Finally, numerical results demonstrate the theoretical convergence and effectiveness of the fast algorithm.

The retrogradation properties of lotus seed starch (LS) blended with the hydrocolloids arabic gum (AG), carrageenan (CG), guar gum (GG), and xanthan (XN) were investigated undergoing an autoclaving-cooling treatment, a model for starch retrogradation acceleration. Compared with LS alone, LS-AG showed the increases in syneresis, tan δ (more solid-like behavior), bound water content and immobile water content, molecular weight, the intensity at 480 cm

This article shows that ultra violet (UV) micro-embossing can be successfully used for fabricating biocompatible micropatterned films with microchannels separated by high aspect ratio microwalls. Eight series of micropatterns were investigated; the width of the microwall was either 10 or 25 μm and that of the microchannel either 40, 80, 120, or 160 μm. The material investigated was principally polyurethane diacrylate. The UV-embossed micropattern was extracted with methanol, converting the micropatterns from cytotoxic to biocompatible. The typical UV embossing method was modified by using a marginally adhesive polyester substrate, which facilitates demolding but is removable before methanol extraction to avoid fragmentation of the embossed micropatterns. The effect of the micropatterns on A7r5 smooth muscle cells and C2C12 skeletal muscle cells was investigated. The dimensions of both channel and wall have significant effects on the elongation of both muscle cells. In the narrower 40-μm channel, the C2C12 cells merged together to form myofibers. These results indicate that UV-embossed micropatterns may present a useful scaffold for in vitro cell shape and orientation control needed in vascular and muscle tissue engineering. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006

The reconstruction of a functional vascular tunica media, with circumferentially oriented contractile smooth muscle cells (SMCs) and extracellular matrix, appropriate mechanical properties and vasoactivity has yet to be demonstrated for tissue engineering of small diameter blood vessels. Synthetic SMC is desired for cell proliferation needed for vessel remodeling but the contractile phenotype is necessary for sufficient vasoactivity and inhibition of neoinitima formation. The switch of SMC phenotype from synthetic to contractile at the appropriate cell development stage has been hypothesized to be necessary for producing a functional vascular tunica media. DOCTOR OF PHILOSOPHY (MAE)

One of the main challenges in vascular tissue engineering has been mimicking the complex native three-dimensional (3D) architecture of smooth muscle cells (SMCs). In the current study, we performed layer-by-layer (LBL) seeding of SMCs in a microchanneled scaffold, with or without interleaving a thin layer of collagen type I hydrogel, toward fabricating the 3D microarchitecture. This LBL process avoids the "steric hindrance" effect observed in direct 3D culture of SMCs in collagen hydrogel. More importantly, the LBL process enables the building up of multilayers of aligned and confluent SMCs. Within each layer, the SMCs as well as the SMC F-actin and alpha-actin filaments align along the direction of the scaffold microchannels, which would potentially improve the tensile and contractile strength of the tissue engineered construct, desirable properties for an engineered vasculature. In addition, rapid two-dimensional (2D) patterning of SMCs is possible with high seeding density, which makes the LBL method feasible for fabrication of multilayered structures in a short time, rendering it useful in clinical therapeutic applications.