A Skin-Inspired Multifunctional Conductive Hydrogel with High Stretchable, Adhesive, Healable, and Decomposable Properties for Highly Sensitive Dual-Sensing of Temperature and Strain.

Developing smart hydrogels with excellent physicochemical properties and multi-sensing capabilities for various simulation of human skin's functions still remains a great challenge. Here, based on simple and convenient one-step covalent cross-linking method enhanced by dynamic RS-Ag interactions, a skin-inspired multifunctional conductive hydrogel with desirable physicochemical properties (including high stretchability, self-adhesion, self-healing, decomposition and removability) is developed for highly sensitive dual-sensing of temperature and strain. Benefiting from the synergistic action of multiple hydrogen bonds, RS-Ag bonds and S-S bonds, the gel exhibited a novel thermosensitive mechanism. The prepared hydrogels exhibited extremely high mechanical properties (maximum tensile strength of 0.35 MPa, elongation at break nearly 1800%, compressive stress over 4.43 MPa), excellent self-healing (96.82% (stress), 88.45% (temperature), 73.89% (mechanical property)), decomposition (the molecular weight after decomposition is below 700) and self-adhesion (enhanced contact with the material interface). In addition, this conductive hydrogel could also simultaneously achieve highly sensitive temperature-sensing (TCR: 10.89) and stress-sensing (GF: 1.469). As a proof-to-concept, the hydrogel displayed superior capability for simulation of human skin to perception of touch, pressure and ambient temperature simultaneously, indicating promising applications in the fields of wearable devices, personal health care, and human-machine interfaces.

KRT17 Promotes the Activation of HSCs via EMT in Liver Fibrosis.

Background and Aims: Although activation of hepatic stellate cells (HSCs) plays a central role in the development of liver fibrosis, the mechanism underlying the activation of HSCs remains unclear. Keratin 17 (KRT17), a member of the intermediate filament family, can regulate tumor cell proliferation and migration. The current study aimed to elucidate the role of KRT17 in the activation of HSCs and the mechanisms underlying liver fibrosis. Methods: The expression of KRT17 was determined using immunohistochemistry in tissue microarray. Western blotting and qRT-PCR assays were used to determine the KRT17 expression in fibrotic liver tissues obtained from human subjects and mice. LX-2 cells were treated with TGF-ß1 recombinant protein and adipocyte differentiation mixture (MDI) mix to induce and reverse LX-2 cell activation, respectively, in order to explore the correlation between KRT17 and HSC activation. Additionally, cell proliferation and migration abilities of LX-2 cells transfected with KRT17-overexpressing plasmid or small interfering RNA were determined using CCK-8, flow cytometry, Transwell, and wound healing assays. Finally, rescue assay was used to explore the role of KRT17 in HSC activation and epithelial-mesenchymal transition (EMT). Results: The expression of KRT17 was higher in the human and mouse fibrotic liver tissues than in healthy liver tissues, and it was positively correlated with HSC activation. Upregulated KRT17 enhanced proliferation, migration, HSC activation and EMT in LX-2 cells, while knockdown of KRT17 reversed these effects. TGF-ß1 recombinant protein accelerated KRT17-mediated EMT, HSC activation and proliferation, while TGF-ß1 inhibitor counteracted the effect of KRT17 in vitro. Conclusions: KRT17 promoted HSC activation, proliferation and EMT in hepatic fibrosis probably via TGF-ß1 signaling, and KRT17 might serve as a therapeutic target for the treatment of liver fibrosis.

A homeotropic main-chain tolane-type liquid crystal elastomer film exhibiting high anisotropic thermal conductivity.

The development of pure polymeric films with anisotropic thermal conductivities for electronic device packaging applications has attracted intense scientific attention. In order to enhance the polymeric film's normal-direction thermal conductivity, homeotropic alignment of macromolecular chains is the primary concern. One of the promising preparation strategies is to perform in situ photopolymerization of homeotropic-oriented liquid crystal monomers. In this work, we design and synthesize a novel tolane-core thiol-ene-tailed liquid crystal monomer. Benefitting from the conjugated and extended tolane π-system of the mesogenic core and length extension of the terminal aliphatic tails, the normal-to-plane thermal conductivity value and the thermal conductivity anisotropy value of the corresponding cross-linked main-chain end-on liquid crystal polymer (xMELCP) film reach 3.56 W m-1 K-1 and 15.0, respectively. Compared with the data of a previously reported ester-type thiol-ene xMELCP film, the two primary values of this novel tolane-type thiol-ene xMELCP material are increased dramatically by 46% and 29%, respectively.