Structurally Transformable and Reconfigurable Hydrogel-Based Mechanical Metamaterials and Their Application in Biomedical Stents.

Mechanical metamaterials exhibit several unusual mechanical properties, such as a negative Poisson's ratio, which impart additional capabilities to materials. Recently, hydrogels have emerged as exceptional candidates for fabricating mechanical metamaterials that offer enhanced functionality and expanded applications due to their unique responsive characteristics. However, the adaptability of these metamaterials remains constrained and underutilized, as they lack integration of the hydrogels' soft and responsive characteristics with the metamaterial design.

Evolution of Oxygen Content of Graphene Oxide for Humidity Sensing.

Graphene oxide (GO) has shown significant potential in humidity sensing. It is well accepted that the oxygen-containing functional groups in GO significantly influence its humidity sensing performance. However, the relationship between the content of these groups and the humidity sensing capability of GO-based sensors remains unclear.

Sustainable Vat Photopolymerization-Based 3D-Printing through Dynamic Covalent Network Photopolymers.

Vat photopolymerization (VPP) based three-dimensional (3D) printing, including stereolithography (SLA) and digital light projection (DLP), is known for producing intricate, high-precision prototypes with superior mechanical properties. However, the challenge lies in the non-recyclability of covalently crosslinked thermosets used in these printing processes, limiting the sustainable utilization of printed prototypes. This review paper examines the recently explored avenue of VPP 3D-printed dynamic covalent network (DCN) polymers, which enable reversible crosslinks and allow for the reprocessing of printed prototypes, promoting sustainability.

Study on the Reactivity Activation of Coal Gangue for Efficient Utilization.

In this study, the research aim is to enhance the activity index of activated coal gangue and study its activation mechanism. The activation process of coal gangue was optimized through orthogonal tests, and the Back-Propagation (BP) neural network model was improved using a genetic algorithm. With the effects of grinding duration, calcination temperature, and calcination duration, the morphological changes and phase transformation processes of coal gangue were studied at the micro and meso levels to clarify the activation mechanism.

4D-Printed Hydrogel Actuators through Diffusion-Path Architecture Design.

Recently, smart hydrogels have garnered considerable attention as biomedical devices, and several approaches have been introduced for their fabrication, including the incorporation of stimulus-responsive additives, utilization of molecular imprinting techniques, and application of multilayered hydrogels. However, the nonuniform properties resulting from these approaches limit the practical applications of hydrogels by causing inconsistent performance and behavior. In this study, we propose a novel approach to manipulating the swelling kinetics of hydrogels by engineering their diffusion-path architecture.

[Research progress of tibial-graft fixation methods on anterior cruciate ligament reconstruction].

Objective: To review the studies about the tibial-graft fixation methods on anterior cruciate ligament (ACL) reconstruction, in order to provide clinical reference.

Methods: The literature about the tibial-graft fixation methods on ACL reconstruction at home and abroad was extensively reviewed, and the factors that affect the selection of fixation methods were summarized.

Results: The knee flexion angle, graft tension, and graft fixation device are mainly considered when the tibial-graft was fixed on ACL reconstruction.

Effects of phosphine ligands in nickel-catalyzed decarbonylation reactions of lactone.

Due to the ubiquity of carbonyl compounds and the abundance of nickel on the earth, nickel-catalyzed decarbonylation has garnered increasing attention in recent years. This type of reaction has seen significant developments in various aspects; however, certain challenges concerning reactivity, selectivity, and transformation efficiency remain pressing and demand urgent resolution. In this study, we employed DFT calculations to investigate the mechanism of nickel-catalyzed decarbonylation reactions involving lactones, as well as the effects of phosphine ligands.

Enhancing the mechanical strength and toughness of epoxy resins with linear POSS nano-modifiers.

Glass transition temperature ( ) always deteriorates while improving the strength of epoxy resins which inherently suffer from brittleness. Herein, novel linear polyhedral oligomeric silsesquioxane (POSS)-epoxy nano-modifiers are synthesized with variable contents of POSS. The thermomechanical properties and chemical structure study of the POSS-epoxy indicates significant differences of the rigid POSS content in the linear nano-modifiers.

Toughened Hydrogels for 3D Printing of Soft Auxetic Structures.

Materials with negative Poisson's ratio have attracted considerable attention and offered high potential applications as biomedical devices due to their ability to expand in every direction when stretched. Although negative Poisson's ratio has been obtained in various base materials such as metals and polymers, there are very limited works on hydrogels due to their intrinsic brittleness. Herein, we report the use of methacrylated cellulose nanocrystals (CNCMAs) as a macro-cross-linking agent in poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels for 3D printing of auxetic structures.

Comparison of Rapid Rehabilitation after Anterior Cruciate Ligament Reconstruction with Tensioning Technique and Traditional Rehabilitation.

To investigate the efficacy of a fast rehabilitation program for the recovery of knee joint function after arthroscopic autologous hamstring tendon transplantation for reconstruction of the anterior cruciate ligament (ACL), from January 1, 2017, to March 31, 2019, a total of 65 patients with ACL injury were randomly divided into a study group and a control group. Both groups were treated with autologous hamstring tendon to reconstruct the anterior cruciate ligament, arthroscopic transplantation, and decompression techniques. The research group was treated with a fast rehabilitation program.

Correlations between forkhead box D1 expression and clinicopathological characteristics of patients with bladder cancer and influence on biological behaviors of bladder cancer cells.

Objectives: To investigate the correlationsbetween forkhead box D1 (FOXD1) expressionand clinicopathological characteristics of bladdercancer and influence on the biological behaviors ofbladder cancer cells.

Methods: The overall survival rate of 87 bladdercancer patients was evaluated to explore the predictivevalue of FOXD1. The expressions of FOXD1 in 87 bladdercancer tissues and 26 adjacent tissues were measuredthrough immunohistochemistry, and the correlationsbetween FOXD1 expression and clinicopathologicalcharacteristics of patients were analyzed.

LINC00665 regulates hepatocellular carcinoma by modulating mRNA via the m6A enzyme.

This study aimed to reveal the mechanism by which long noncoding RNAs (lncRNAs) modulate hepatocellular carcinoma (HCC) by regulating mRNA via the N6-methyladenosine (m6A) enzyme. The expression and clinical data of 365 HCC patients and 50 healthy control samples were downloaded from the the Cancer Genome Atlas (TCGA) database. Differentially expressed lncRNAs (DElncRNAs) and differentially expressed mRNAs (DEmRNAs) screened using limma packages from the R.

Effects of Coculture Fibroblasts and Vascular Endothelial Cells on Proliferation and Osteogenesis of Adipose Stem Cells.

Background: The development of tissue engineering provides a new method for the clinical treatment of bone defects, but the problems of slow formation and slow vascularization of tissue engineered bone have always existed. Studies have shown that the combined culture system of vascular endothelial cells and adipose stem cells is superior to single cell in repairing bone defects. With the excellent proliferation ability, secretion of synthetic collagen and a variety of regulatory factors and fibroblasts can differentiate into osteoblasts and have the potential to be excellent seed cells involved in tissue engineering bone construction.

Biomaterials by design: Harnessing data for future development.

Biomaterials is an interdisciplinary field of research to achieve desired biological responses from new materials, regardless of material type. There have been many exciting innovations in this discipline, but commercialization suffers from a lengthy discovery to product pipeline, with many failures along the way. Success can be greatly accelerated by harnessing machine learning techniques to comb through large amounts of data.

Effects of Tissue-engineered Bone by Coculture of Adipose-derived Stem Cells and Vascular Endothelial Cells on Host Immune Status.

Aim: The study aimed to explore the effects of tissue-engineered bone constructed with partially deproteinized biologic bone (PDPBB) and coculture of adipose-derived stem cells (ADSCs) and vascular endothelial cells (VECs) on host immune status, providing a very useful clue for the future development of bone engineering.

Methods: Tissue-engineered bones constructed by PDPBB and ADSCs, VECs or coculture of them were implanted into the muscle bag of bilateral femurs of Sprague-Dawley rats. Partially deproteinized biologic bone alone and blank control were also implanted.

Machine Learning-Driven Biomaterials Evolution.

Biomaterials is an exciting and dynamic field, which uses a collection of diverse materials to achieve desired biological responses. While there is constant evolution and innovation in materials with time, biomaterials research has been hampered by the relatively long development period required. In recent years, driven by the need to accelerate materials development, the applications of machine learning in materials science has progressed in leaps and bounds.

[Comparative study on effectiveness of posterior-posterior triangulation technique and anteroposterior approach for arthroscopic posterior cruciate ligament reconstruction].

Objective: To investigate the effectiveness of the posterior-posterior triangulation technique for arthroscopic posterior cruciate ligament (PCL) reconstruction by comparing with the anteroposterior approach.

Methods: Retrospective analysis was performed on 40 patients who underwent arthroscopic PCL reconstruction between February 2016 and February 2020. The PCLs were reconstructed via anteroposterior approach in 20 patients (anteroposterior approach group) and posterior-posterior triangulation technique in 20 patients (posterior-posterior triangulation technique group).

A novel full endoscopic annular repair technique combined with autologous conditioned plasma intradiscal injection: a new safe serial therapeutic model for the treatment of lumbar disc herniation.

Background: Recurrent intervertebral disc herniation and an exacerbated degenerative process have been identified as the most important factors contributing to persistent pain and disability after surgical discectomy. Defects in the annulus fibrosus remain a surgical challenge, as the preference for minimally invasive surgical approaches for lumbar microdiscectomy, surgical access, and the specifics of anatomy limit the types of devices that permit annulus fibrosus repair. Furthermore, the intervertebral disc is a relatively avascular structure, and surgical procedures can accelerate the degenerative disc process.

Construction of tissue engineering bone with the co‑culture system of ADSCs and VECs on partially deproteinized biologic bone : A preliminary study.

Scaffold‑based bone tissue engineering has therapeutic potential in the regeneration of osseous defects. The present study aimed to explore the adhesion and cell viability of a co‑culture system composed of vascular endothelial cells PI/Annexin V represents early apoptotic cells, and PI/Annexin V represents late apoptotic cells (VECs) and adipose‑derived stem cells (ADSCs) on partially deproteinized biologic bone (PDPBB) , and determine the optimum time period for maximum cell viability that could possibly be used for standardizing the scaffold transplant into the system. VECs and ADSCs were isolated from pregnant Sprague‑Dawley rats and confirmed by immunostaining with von Willebrand factor and CD90, respectively.

Expressions and relationship of Krüppel-like factor 15 and endothelial nitric oxide synthase in experimental deep venous thrombosis.

Background: Deep vein thrombosis (DVT) is an early postoperative complication. Thrombosis formation, which is potentially life-threatening, seriously affects the rehabilitation of patients after surgery. We aimed to establish a C57 mouse model of DVT and to examine the changes in the expression of Krüppel-like factor 15 (KLF15) and endothelial nitric oxide synthase (eNOS) in venous wall tissues, and we also investigated the regulatory relationship of KLF15 and eNOS in the thrombin-induced human umbilical vein endothelial cell (HUVEC) injury cell model.

Repair of Bone Defects With Endothelial Progenitor Cells and Bone Marrow-Derived Mesenchymal Stem Cells With Tissue-Engineered Bone in Rabbits.

Purpose: This study aimed to investigate the repair of bone defects in rabbits with tissue-engineered bones using cocultured endothelial progenitor cells (EPCs) and bone marrow mesenchymal stem cells (BMSCs) as seeding cells.

Methods: Endothelial progenitor cells and BMSCs were isolated and purified from the peripheral blood and bone marrow, respectively, of New Zealand rabbits. The third passage of BMSCs was cultured alone or with EPCs.

kinetics predictions for the role of pre-reaction complexes in hydrogen abstraction from 2-butanone by OH radicals.

The existence of pre- and post-reaction complexes has been proposed to influence hydrogen abstraction reaction kinetics, but the significance still remains controversial. A theoretical study is presented to discuss the effects of complexes on hydrogen abstraction from 2-butanone by OH radicals based on the detailed PESs at the DLPNO-CCSD(T)/aug-cc-pVTZ//M06-2x-D3/may-cc-pVTZ level with five pre-reaction complexes at the entrance of the channels and four post-reaction complexes at the exit. The hydrogen bond interactions, steric effects, and contributions to the bonding orbital of the OH radical species and 2-butanone species in the complex structures were visualized and investigated by wavefunction analyses.

Star-Shaped Crosslinker for Multifunctional Shape Memory Polyurethane.

Star-shaped cyclophosphazene (ACP) was employed as covalent crosslinker to form a rigid segment in polyurethanes network, to enhance the mechanical performance and to add extra flame retardant property. The effects of different ACP contents on the shape memory ability and fire resistance performance of polyurethane (PU) were studied. Tensile tests suggested high flexibility of the PUs with the maximum elongation-at-break of 161.