Search

Amyloid fibrils’ stable structure and nice biocompatibility make them good candidates as the templates used in engineering and biomedicine. While palladium nanoparticles have been widely used as catalysts, their high surface energy results in aggregation of nanoparticles, leading to decreased catalytic activities. Here, we investigated the catalytic performance of palladium nanoparticles-deposited lysozyme amyloid fibrils through the reduction of methylene blue (MB). The palladium nanoparticles-decorated lysozyme fibrils were first synthesized and then characterized using several analytical tools. The progress of reductive MB degradation in the presence of sodium borohydride was monitored via UV–Vis spectrophotometry to investigate the catalytic efficiency of bare palladium nanoparticles and palladium nanoparticle/lysozyme fibril hybrids under different conditions. The kinetic data were analyzed using a pseudo-first order model. Finally, the magnitudes of apparent rate constants under different conditions and associated activation parameters were determined. We found that the level of nanoparticle aggregation decreased and the degree of MB conversion significantly increased upon incorporation of amyloid fibrils as the supporting carriers. Moreover, a lower activation energy was perceived when MB reduction was catalyzed by the palladium nanoparticle/fibril hybrids as compared with the bare nanoparticle counterpart. This study presents a nice example of applying amyloid fibril-based hybrid materials in one of the important engineering fields - catalysis.

Cybersickness is one of the challenges that has prevented the widespread adoption of Virtual Reality (VR) and its applications. Due to its importance, there have been extensive studies on understanding and reducing cybersickness. Inspired by previous work that has sought to reduce cybersickness by applying the blurring effect and reducing the field of view of VR scenes, we present a simulation with controllable peripheral blur in the VR image. The simulation can be used to study cybersickness and spatial knowledge acquisition in an engaging virtual walking scenario.

In this work, we present a facile preparation of a paper-based glucose assay for rapid, sensitive, and quantitative measurement of glucose in blood plasma and urine. Two copper phosphorescent complexes [Cu(2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline)(2,6-dimethylphenylisocyanide)2][B(C6H3(CF3)2)4] (Cu1) and [Cu(2,9-dimethyl-1,10-phenanthroline)(2,6-dimethylphenylisocyanide)2][B(C6H3(CF3)2)4] (Cu2) and a new silver congener [Ag(P3)CNAg(P3)][B(C6H3(CF3)2)4] (Ag3) (P3 = PPh2C6H4-PPh-C6H4PPh2 [bis(o-diphenylphosphinophenyl)phenylphosphine]) have been synthesized and their oxygen sensing abilities were investigated. The dimetallic phosphine-based Ag3 complex, having a high oxygen sensing ability, was employed as an efficient signal transducer in enzymatic reactions to recognize blood plasma glucose and urine glucose, which provided a wide linear response for a concentration range between 1.0 and 35 mM and a rapid response, with a limit of detection (LOD) of 0.09 mM for glucose. In practical application, this Ag3 paper-based device offers great analytical reliability and accuracy upon monitoring glucose concentrations in blood plasma.

In this work, we present a Ag@Au nanoprism-metal-organic framework-paper based glucose sensor for rapid, sensitive, single-use and quantitative glucose determination in human serum. To achieve painless measurement of glucose with a non-invasive detection methodology, this biosensor was further tested in human urine. In this approach, a new hybrid-Ag@Au nanoprism loaded in close proximity to micrometer sized coordination polymers as phosphorescent luminophores significantly enhanced the emission intensity due to metal-enhanced phosphorescence and worked as reaction sites to support more dissolved oxygen. Reports of enhanced phosphorescence intensity are relatively rare, especially at room temperature. The true enhancement factor of Ag@Au-phosphorescent metal-organic frameworks on paper was deduced to be 110-fold, making it a better optical type glucose meter. The results demonstrate the validity of the intensity enhancement effect of the excitation of the overlap of the emission band of a luminophore with the surface plasmon resonance band of Ag@Au nanoprisms. Ag@Au nanoprisms were used not only to improve the detection limit of glucose sensing but also to extend the glucose sensing range by enhancing the oxygen oxidation efficiency. The oxidation of glucose as glucose oxidase is accompanied by oxygen consumption, which increases the intensity of the phosphorescence emission. The turn-on type paper-based biosensor exhibits a rapid response (0.5 s), a low detection limit (0.038 mM), and a wide linear range (30 mM to 0.05 mM), as well as good anti-interference, long-term longevity and reproducibility. Finally, the biosensor was successfully applied to the determination of glucose in human serum and urine.

The electrospun scaffold plays a crucial role in tissue engineering for its unique structure which can mimic the structure and biological functions of the natural extracellurlar matrix (ECM). This study discuss the effects of electrospinning parameters, such as applied voltage, tip-collector distance, DMF content percentage and polymer concentration, on the porosity and the surface area of electrospun fibrous scaffolds. The results show that the fiber diameter of electrospun scaffold can be increased with the lower applied voltage, the shorter the tip-collector distance, the smaller DMF content percentage or the higher the polymer concentration. The PCL electrospun scaffolds have high porosity ranging from 85.5 to 92.4%. Furthermore, the surface area to volume ratio exhibits a clear relationship with the fiber diameter. The surface area can be improved through decreasing the diameter of nanofibers.

This paper studied the irreversible plastic deformation of PVDF monofilament. The four-element creep model was applied to obtain the theoretical creep curves with experimental data using nonlinear regression. The results were compared to the commonly used material PP monofilament. The results showed that four-element model was a suitable model to describe the creep behavior of PVDF monofilament. PVDF monofilament exhibited reduced irreversible plastic deformation under different stresses and elongation rates. It was more stable and recoverable. PVDF could be an advantageous alternative suture material to the traditional suture materials.

In light of the growing incidence of oral cancer in Taiwan, this study is aimed at investigating the antitumor activity of 3,3'-diindolylmethane (DIM), an active metabolite of the phytochemical indole-3-carbinol (I3C), in oral squamous cell carcinoma (OSCC). DIM exhibited substantially higher antiproliferative potency than I3C in three OSCC cell lines with IC(50) values in SCC2095, SCC9, and SCC15 cells, respectively, of 22 versus 168μM, 25 versus 176μM, and 29versus 300μM. Flow cytometric analysis and Comet assay indicated that DIM suppressed the viability of SCC2095 cells by inducing apoptosis and G2/M arrest. Western blot analysis of various signaling markers revealed the ability of DIM to target pathways mediated by Akt, mitogen-activated protein (MAP) kinases, nuclear factor (NF)-κB, and p53, of which the concerted action underlined its antitumor efficacy. The concomitant inactivation of Akt and MAP kinases in response to DIM facilitated the dephosphorylation of the proapoptotic protein Bad at Ser-136 and Ser-112, respectively. Through endoplasmic reticulum (ER) stress, DIM stimulated the activation of p53 via Ser-15 phosphorylation, leading to increased expression of the BH3-only proapoptotic Bcl-2 members Puma and Noxa. Together, these changes decreased the mitochondrial threshold for apoptosis. G2/M arrest might be attributable to the suppressive effect of DIM on the expression of cyclin B1 and cdc25c. As many downstream effectors of the Akt-NF-κB pathway, including glycogen synthase kinase 3β, IκB kinase α, and cyclooxygenase-2, have been shown to promote oral tumorigenesis, the ability of DIM to inhibit this signaling axis underscores its chemopreventive potential in oral cancer.

The aberrant regulation of epigenetic systems including histone acetylation contributes to inappropriate gene expression in cancer cells. In this study, we investigated the antitumor effects of the novel histone deacetylase inhibitor (S)-HDAC42 in oral squamous cell carcinoma (OSCC) cells. The antiproliferative effect of (S)-HDAC42 was multifold higher than that of suberoylanilide hydroxamic acid in a panel of oral squamous carcinoma cell lines examined. (S)-HDAC42 mediated caspase-dependent apoptosis by targeting multiple signaling pathways relevant to cell cycle progression and survival. We demonstrated that (S)-HDAC42 downregulated the levels of phospho-Akt, cyclin D1, and cyclin-dependent kinase 6, accompanied by increased p27 and p21 expression. In addition, (S)-HDAC42 suppressed NF-κB signaling by blocking tumor necrosis factor-α-induced nuclear translocation, and activated reactive oxygen species generation. Finally, (S)-HDAC42 exhibited high potency in suppressing OSCC tumor growth in a Ca922 xenograft nude mouse model. Together, these findings underscore the translational value of (S)-HDAC42 in fostering new therapeutic strategies for OSCC.