Peritoneal dialysis-related peritonitis causes the denudation of mesothelial cells and, ultimately, membrane integrity alterations and peritoneal dysfunction. Because heat shock protein 72 (HSP72) confers protection against apoptosis and because autophagy mediates survival in response to cellular stresses, we examined whether autophagy contributes to HSP72-mediated cytoprotection in lipopolysaccharide (LPS)-induced peritonitis. Exposure of cultured peritoneal mesothelial cells to LPS resulted first in autophagy and later, apoptosis. Inhibition of autophagy by 3-methyladenine or Beclin-1 small-interfering RNA sensitized cells to apoptosis and abolished the antiapoptotic effect of HSP72, suggesting that autophagy activation acts as a prosurvival mechanism. Overexpression of HSP72 augmented autophagy through cJun N-terminal kinase (JNK) phosphorylation and Beclin-1 up-regulation. Suppression of JNK activity reversed HSP72-mediated Beclin-1 up-regulation and autophagy, indicating that HSP72-mediated autophagy is JNK dependent. In a rat model of LPSassociated peritonitis, autophagy occurred before apoptosis in peritoneum. Up-regulation of HSP72 by geranylgeranylacetone increased autophagy, inhibited apoptosis, and attenuated peritoneal injury, and these effects were blunted by down-regulation of HSP72 with quercetin. Additionally, blocking autophagy by chloroquine promoted apoptosis and aggravated LPSassociated peritoneal dysfunction. Thus, HSP72 protects peritoneum from LPS-induced mesothelial cells injury, at least in part by enhancing JNK activation-dependent autophagy and inhibiting apoptosis. These findings imply that HSP72 induction might be a potential therapy for peritonitis.

Diblock polystyrene-6(oc/e-poly(methacrylic acid) polymers have been synthesized using anionic polymerization techniques incorporating an average of one naphthalene per polymer at either the beginning of the polystyrene block or at the junction between the polystyrene and poly(methacrylic acid) blocks. These polymers have been shown in earlier work to form stable micelles in solvent mixtures from 80:20 dioxane/H20 to pure water. In the present paper we have examined the ability of these polymers to adsorb on polystyrene films and have used photophysical techniques to deduce the exposure of the naphthalene group to the aqueous phase. Scanning electron microscopy images demonstrate that the intact micelle adsorbs onto the polystyrene surface and can achieve a nearly close-packed monolayer coverage. The micelles adhere tenaciously to the polystyrene film and lower the contact angle of water from ca. 90°for untreated polystyrene to 30-40°after surface adsorption. The naphthalene groups at the polystyrenepoly(methacrylic acid) junction are partially exposed to the aqueous phase while the naphthalene at the poly(styrene) end is totally protected.

The Rockall score is clinically useful, rapid and accurate in predicting rebleeding, surgery and mortality outcomes in elderly patients with AUGIB.

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Conductive hydrogels are promising multifunctional materials for wearable sensors, but their practical applications require combined properties that are difficult to achieve. Herein, we developed a flexible wearable sensor with double-layer structure based on conductive composite hydrogel, which included the outer layer of silicone elastomer (Ecoflex)/ silica microparticle composite film and the inner layer of P(AAmco-HEMA)-MXene-AgNPs hydrogel. Through covalently crosslinking silicone elastomer on the surface of the hydrogel polymer, we bonded a thin Ecoflex film (100 μm) on the P(AAm-co-HEMA)-MXene-AgNPs hydrogel with robust interface, which can easily adhere to the Ecoflex/SiO 2 microparticle composite film by silicone glue. The Ecoflex/SiO 2 microparticle composite film endows the strain wearable sensor with superhydrophobic function that could maintain the stability under stretching or bending. Moreover, it can effectively resist the interference of water droplets and water flow. The P(AAm-co-HEMA)-MXene-AgNPs hydrogel exhibits outstanding antibacterial activity to inhibit Staphylococcus aureus, Escherichia coli, and even drug-resistant Escherichia coli. In addition, the flexible wearable sensor exhibited good self-adhesive performance by changing the reaction temperature of hydrogel and can adhere strongly onto various materials. The conductive composite hydrogel reported in this work contributes an innovative strategy for the preparation of multifunctional flexible wearable sensor.

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