Search

Macrophages are highly heterogeneous and exhibit a diversity of functions and phenotypes. They can be divided into pro‐inflammatory macrophages (M1) and anti‐inflammatory macrophages (M2). Diabetic wounds are characterized by a prolonged inflammatory phase and difficulty in healing due to the accumulation of pro‐inflammatory (M1) macrophages in the wound. Therefore, hydrogel dressings with macrophage heterogeneity regulation function hold great promise in promoting diabetic wound healing in clinical applications. However, the precise conversion of pro‐inflammatory M1 to anti‐inflammatory M2 macrophages by simple and biosafe approaches is still a great challenge. Here, an all‐natural hydrogel with the ability to regulate macrophage heterogeneity is developed to promote angiogenesis and diabetic wound healing. The protocatechuic aldehyde hybridized collagen‐based all‐natural hydrogel exhibits good bioadhesive and antibacterial properties as well as reactive oxygen species scavenging ability. More importantly, the hydrogel is able to convert M1 macrophages into M2 macrophages without the need for any additional ingredients or external intervention. This simple and safe immunomodulatory approach shows great application potential for shortening the inflammatory phase of diabetic wound repair and accelerating wound healing. [ABSTRACT FROM AUTHOR]

Alkylation of benzene with ethylene to ethylbenzene over a β-zeolite catalyst is carried out in the five different near critical regions. With the application of X-ray diffraction (XRD) and scanning electron microscope (SEM), structures of the catalysts used under the five different near critical conditions are compared with those of the fresh catalyst. The results show that the high pressure operating conditions, including the supercritical fluid operation, may be harmful to the catalyst structure, and the operation in the vapor–liquid state near the critical point may cause heavy destruction to the catalyst. The coking mechanism of the catalysts is suggested based on element material analysis (EMA) and electron paramagnetic resonance (EPR) characterization. Supercritical and other near critical operations are compared. [Copyright &y& Elsevier]

• Loureirin A attenuates IL-1β induced ECM degradation in chondrocytes. • Loureirin A regulates the NF-κB pathway via Inhibition AKT phosphorylation in IL-1β stimulated chondrocytes. • Loureirin A attenuates IL-1β induced Oxidative stress via activation of Nrf2/HO-1 signaling pathway. • Loureirin A ameliorates the osteoarthritis in vivo. Osteoarthritis(OA) is one of the most common diseases in orthopedics. It is characterized by degeneration of articular cartilage and chronic inflammation. In this study, we aim to elucidate the mechanism of Loureirin A's therapeutic effect in OA progression. In vitro, Loureirin A pretreatment can significantly inhibit production of NO, PGE2, COX-2, TNF-α, iNOS andIL-6 induced by IL-1β in mouse articular chondrocytes. Moreover, Loureirin A suppressed the expression of matrix metalloproteinase-9(MMP-9), which leads to degradation of the extracellular matrix. The degradation of aggrecan and type II collagen protein in the extracellular matrix (ECM) stimulated by IL-1β was reversed. For signal pathway research, Loureirin A dramatically inhibited the phosphorylation of AKT and subsequent NF-κB entering into the nucleus caused by IL-1β in chondrocytes. Besides, a number of related indicators suggested that Loureirin A has a strong antioxidant activity in the treatment of osteoarthritis via increasing content of SOD2 and suppressing MDA and ROS. In addition, in vivo study demonstrated that Loureirin A could ameliorated the progression of OA in mice DMM model In conclusion, all results showed that Loureirin A may be a potential therapeutic candidate for the OA. [ABSTRACT FROM AUTHOR]

Background: Phage display technology has been established as a powerful screening approach to select ligands or peptides for binding to proteins. Despite rapid growth in the field, there has been a relative dearth of quantitative criteria to measure the effectiveness of the process of phage display screening. Since human serum albumin (HSA) has been extensively studied as a drug carrier to extend the plasma half-life of protein therapeutics, the use of phage display technology is required for identifying albumin-binding peptides as the very promising strategy of albumin-binding against albumin fusion. The construction of albumin-binding drug requires the assessment of a large quantity of HSA-binding peptide (HSA binder) candidates for conjugation with therapeutic proteins. The use of the linear epitope mapping method has allowed researchers to discover many HSA-binding peptides. However, it may be inefficient to select these peptides based on sequence identity via randomly sequencing individual phage clones from enrichment pools., Method: Here, a simple assessment method to facilitate phage display selection of HSA-binding peptides was recommended. With experimentally determined phage titer, one can calculate the specificity ratios, the recovery yields and the relative dissociation constants, which are defined as quantitative criteria for panning and characterization of the binding phage fused peptides., Results: Consequently, this approach may not only enable more rapid and low-cost phage display screening, but also efficiently reduce pseudo-positive phages selected as HSA binders for conjugation with therapeutic proteins., Competing Interests: The author declares there are no competing interests., (©2023 Shi.)

In E. coli and related species, flagellar brake protein YcgR responds to the elevated intracellular c-di-GMP, decreases the flagellar rotation speed, causes a CCW rotation bias, and regulates bacterial swimming. Boehm et al. suggested that c-di-GMP-activated YcgR directly interacted with the motor protein MotA to curb flagellar motor output. Paul et al. proposed that YcgR disrupted the organization of the FliG C-terminal domain to bias the flagellar rotation. The target proteins are controversial, and the role of motor proteins remains unclear in flagellar rotation speed and direction regulation by YcgR. Here we assayed the motor proteins' affinity via a modified FRET biosensor and accessed the role of those key residue via bead assays. We found that YcgR could interact with both MotA and FliG, and the affinities could be enhanced upon c-di-GMP binding. Furthermore, residue D54 of YcgR-N was needed for FliG binding. The mutation of the FliG binding residue D54 or the MotA binding ones, F117 and E232, restored flagellar rotation speed in wild-type cells and cells lacking chemotaxis response regulator CheY that switched the flagellar rotation direction and decreased the CCW ratio in wild-type cells. We propose that c-di-GMP-activated YcgR regulated the flagellar rotation speed and direction via its interaction with motor proteins MotA and FliG. Our work suggest the role of YcgR-motor proteins interaction in bacterial swimming regulation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Han, Wang, Qian, Guo, Shi, He, Yuan, Hou and Li.)