Matrix Degradation Research Articles

Empagliflozin treatment pre- and post- acute myocardial infarction reduces no-reflow, inflammatory cell infiltration and infarct size while preserving cardiac function.

Abstract Background and aims Empagliflozin (EMPA) and other members of the family of sodium glucose co-transporter 2 inhibitors have demonstrated clinical benefit in terms of survival and rehospitalizations in heart failure. However, their effect on acute myocardial infarction (AMI) is still under investigation. Microvascular injury (MVI) and no-reflow are major determinants of myocardial infarct size (IS) and prognosis. We investigated EMPA’s cardioprotective potential in AMI in terms of no-reflow, MVI and IS emphasizing on a translational regimen with EMPA treatment after AMI. Methods In a first series of experiments, C57Bl6 male mice (n=10 per group) were randomized into 1) Sham, 2) Control-AMI and 3) EMPA-Pre-AMI (10mg/kg/day orally for 6 weeks) groups. Mice underwent 30 min ischemia (I) and 2h reperfusion (R) or sham operation. Cell sorting and 3’ mRNA sequencing were applied to identify the cell types that are transcriptionally affected by EMPA pretreatment in mice with AMI. In a second series of experiments, the protocol was repeated, and an additional group was added, EMPA-Post-AMI (n=8-11 mice per group) in which oral treatment was performed 1h after R. Assessment of no-reflow via thioflavin S staining and electron microscopy was performed at 48 h. The infiltration of inflammatory cells in the ischemic heart was examined via flow cytometry. IS and myocardial function were determined by cardiac magnetic resonance (CMR). Type-2 diabetes mellitus patients received insulin (n=18) or EMPA (n=24) within 2 months post-AMI. Endothelial glycocalyx and endothelial-related circulating markers were examined at 4 months and 12 months post-AMI. Results EMPA pretreatment reversed AMI-induced alterations in cardiac endothelial cells’ (ECs) transcriptome. As such, it promoted the expression of survival genes, reduced gene expression related to adhesion molecules and ECs matrix degradation. Conversely, EMPA pretreatment exerted minimal effects on cardiomyocyte and fibroblast transcriptome. In support of the effect of EMPA on ECs, EMPA-Pre-AMI and EMPA-Post-AMI groups significantly reduced no-reflow and MVI as indicated by electron microscopy and histology at 48h of R. Moreover, both EMPA treatment pre-AMI and post-AMI reduced the infiltration of inflammatory monocytes and neutrophils in the infarcted myocardium suggesting enhanced vascular integrity. Both EMPA-Pre-AMI and EMPA-Post-AMI reduced IS and preserved cardiac function defined by CMR. Patients receiving EMPA presented with improved endothelial glycocalyx thickness, % global longitudinal strain and preserved pulse wave velocity. Conclusions EMPA treatment either before or after AMI protects against MVI, reduces no-reflow and IS and preserves cardiac function. Our data support the use of EMPA after recanalization in patients with AMI to confer improvement of cardiovascular function.

Intelligent fault diagnosis for tribo-mechanical systems by machine learning: Multi-feature extraction and ensemble voting methods

Timely fault detection is crucial for preventing issues like worn clutch plates and excessive friction material degradation, enhancing fuel efficiency, and prolonging clutch lifespan. This study focuses on early fault diagnosis in dry friction clutch systems using machine learning (ML) techniques. Vibration data is analyzed under different load and fault conditions, extracting statistical, histogram, and auto-regressive moving average (ARMA) features. Feature selection employs the J48 decision tree algorithm, evaluated with eight ML classifiers: support vector machines (SVM), k-nearest neighbor (kNN), linear model tree (LMT), random forest (RF), multilayer perceptron (MLP), logistic regression (LR), J48, and Naive Bayes. The evaluation revealed that individual classifiers achieved the highest testing accuracies with statistical feature selection as 83% for both MLP and LR at no load, 90% for MLP at 5 kg, and 93% for KNN at 10 kg. For histogram feature selection, KNN and MLP both reached 85% at no load, MLP achieved 91% at 5 kg, and RF attained 97% at 10 kg. With ARMA feature selection, KNN reached 93% at no load, LR achieved 94% at 5 kg, and RF reached 86% at 10 kg. The voting strategy notably improved these results, with the RF-KNN-J48 ensemble reaching 98% for histogram features at 10 kg, the KNN-LMT-RF ensemble achieving 94% for ARMA features at no load, and the SVM-MLP-LMT ensemble attaining 95% for ARMA features at 5 kg. Hence, a combination of three classifiers using the majority voting rule consistently outperforms standalone classifiers, striking a balance between diversity and complexity, facilitating robust decision-making. In practical applications, selecting the optimal combination of feature selection method and classifier is vital for accurate fault classification. This study provides valuable guidance for engineers and practitioners implementing robust load classification systems in industrial settings.

Inguinal hernia: a view from the 21st century (a review)

The proposed review is a look at the pathogenesis of inguinal hernia from the standpoint of molecular biology, as well as an attempt to understand the problems that are a consequence of explantation: issues of male fertility, chronic inflammation, carcinogenesis. It is proven that the pathogenesis of inguinal hernia is not reduced to a defect of the anterior abdominal wall. Moreover, the formation of this defect is preceded by a complex of modification of connective tissue components, which is based on the separation of the processes of extracellular matrix synthesis and matrix degradation with the predominance of the latter that disrupts the rotation of structures responsible for mechanical strength and elasticity. From this point of view, inguinal hernia is a multifactorial and heterogeneous disease.

Impact of Biofilms on Surface Properties of Polymethyl Methacrylate (PMMA) Resins.

Poly(methyl methacrylate) (PMMA) resins are widely used in medical and dental applications. Their susceptibility to bacterial biofilm formation poses significant challenges related to material degradation and infection risk. This study investigated the effects of Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) biofilms on PMMA resin surface properties over a 45-day period at 35°C. The study examined various parameters including biofilm adhesion, morphology, surface roughness, hydrophobicity, solid fraction, and zeta potential. PMMA resin specimens were inoculated with bacteria and incubated for 45 days. Biofilm adhesion was visually assessed, while surface characterization was conducted using scanning electron microscopy (SEM), atomic force microscopy (AFM), roughness analysis, contact angle measurements, solid fraction determination, and zeta potential analysis. The P. aeruginosa and S. aureus isolates were selected based on their biofilm-positive characteristics, which were further confirmed using Congo red and biofilm formation assays through crystal violet staining and spectrophotometric analysis. The results demonstrated robust biofilm adhesion on PMMA surfaces. SEM and AFM imaging revealed textured surfaces with elevated structures and depressions within the biofilm matrix. Biofilm-exposed resins exhibited significantly increased roughness (Ra = 164.5 nm, Rq = 169.5 nm) and hydrophobicity (mean angle = 85.5°-90.5°) compared to control samples (Ra = 38-50 nm, angle = 55°). Solid fraction measurements indicated a denser biofilm matrix on exposed resins (0.908) compared to controls (0.65). Additionally, zeta potential values were more negative for biofilm-exposed resins (mean = -84.2 mV) than controls (-45.0 mV). These findings underscore the substantial alterations in PMMA resin surface properties induced by bacterial biofilms, emphasizing the critical need for strategies to prevent biofilm formation and mitigate associated risks in healthcare settings. Future research should focus on developing anti-biofilm coatings or treatments to preserve the integrity and functionality of PMMA materials.

Evaluating the Photocatalytic Activity of Green Synthesized Iron Oxide Nanoparticles

Water pollution from dyes is a major environmental challenge, demanding advanced materials for efficient degradation. In this study, we synthesized iron oxide nanoparticles (IONPs) using an aqueous extract of Senegalia catechu leaves and evaluated their photocatalytic activity in methylene blue (MB) dye degradation under sunlight irradiation. The IONPs were characterized by UV-visible spectroscopy (UV–vis), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS). XRD pattern showed a highly crystalline structure with an average crystallite size of 34.7 nm, while SEM images revealed predominantly spherical particles with uneven surface texture. Photocatalytic efficiency exceeded 80% MB dye degradation after 120 min of sunlight exposure. Optimization of catalyst dose, pH, dye concentration, and other parameters is essential for maximizing degradation efficiency. The IONPs demonstrated reusability over four degradation cycles, retaining effective photocatalytic performance. This study underscores the potential of green-synthesized IONPs as eco-friendly photocatalysts for wastewater treatment and environmental remediation.

Upcycling waste polypropylene with basalt fibre reinforcement enhancing additive manufacturing feedstock for advanced mechanical performance

This research seeks to overcome the printing and processing challenges of using waste polypropylene (PP) reinforced with short basalt fibres, transforming them into upcycled feedstock for additive manufacturing. It introduces an optimised method for producing filaments and 3D printing with these materials, addressing common issues such as adhesion and warpage through innovative techniques while achieving maximum mechanical performance in the resulting composites. Basalt fibre weight fractions of 0 %, 2 %, 5 %, 8 %, 15 %, 30 %, and 50 % were used to reinforce the recycled polypropylene, improving both printability and mechanical properties. The tensile strength reached 53.58 MPa at 15 % fibre content, while the flexural strength peaked at 34.06 MPa with 30 % fibre content, revealing distinct interactions between the fibres and polymer under tensile and flexural loading that were not previously observed. Microstructure, voids, debonding, and dispersion were examined using optical and scanning electron microscopy. Differential Scanning Calorimetry (DSC) was performed to assess the thermal behaviour and crystallinity of the recycled polymer during filament production and printing, revealing slight matrix degradation during these processes. The findings highlight the potential of waste basalt fibre-reinforced PP as a valuable filament feedstock for 3D printing, supporting a circular economy approach to composite manufacturing.

Corrosion on cultural heritage buildings in Jordan in current situation and in future climate scenarios

This study examines the impact of air pollution on Jordan’s cultural heritage sites, focusing on key pollutants (SO2, HNO3, O3, PM10) and climate conditions. Using 2019 data and future projections for 2040–2059 and 2080–2099, the research reveals significant material corrosion in urban areas like Amman and Irbid, driven by pollutants such as SO₂ and PM10. Random Forest Analysis identifies these pollutants as primary contributors to material degradation. Future scenarios indicate corrosion rates exceeding safe limits across Jordan, underscoring the need for proactive conservation strategies. This work highlights the critical role of air quality management in protecting cultural heritage, especially under climate change pressures, and provides guidance for national policy development.

Molecular dynamics simulation of punched loop detachment during helium bubble growth in nickel

The coarsening of helium (He) bubbles in nickel-based alloys significantly impacts their service performance. Understanding the underlying mechanisms is crucial for ensuring the long-term durability and reliability of these alloys in reactor radiation environments. Molecular dynamics simulations of single bubble growth at temperatures of 300 and 900 K were conducted using the sequential He atom injection method to investigate the He bubble growth and evolution in nickel. A noteworthy phenomenon observed during bubble growth is the detachment of punched prismatic loops. The critical bubble size for punched loop detachment can be reduced by growing the bubble at a slower rate or lower temperature. The reduction is attributed to the additional time available for the punched loop to dissociate or the higher pressure within the bubble pushing it out. Meanwhile, the formation mechanism of bubble-loop complexes is explored through the interaction of punched loops with nearby punched loops or bubbles. In addition, the integration of these simulation results with variations in material mechanical performance yields valuable insights for interpreting material degradation. This study provides a foundation for improving in-reactor service performance, contributing to a broader understanding of the complex interplay between helium bubble coarsening and material behavior.

Influence of Oligomeric Lactic Acid and Structural Design on Biodegradation and Absorption of PLA-PHB Blends for Tissue Engineering.

The advancing development in biomaterials and biology has enabled the extension of 3D printing technology to the bioadditive manufacturing of degradable hard tissue substitutes. One of the key advantages of bioadditive manufacturing is that it has much smaller design limitations than conventional manufacturing and is therefore capable of producing implants with complex geometries. In this study, three distinct blends of polylactic acid (PLA) and polyhydroxybutyrate (PHB) were produced using Fused Deposition Modeling (FDM) technology. Two of these blends were plasticized with oligomeric lactic acid (OLA) at concentrations of 5 wt% and 10 wt%, while the third blend remained unplasticized. Each blend was fabricated in two structural modifications: solid and porous. The biodegradation behavior of the produced specimens was examined through an in vitro experiment using three different immersion solutions: saline solution, Hank's balanced salt solution (HBSS), and phosphate-buffered saline (PBS). All examined samples were also subjected to chemical analysis: atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), and energy-dispersive spectrometry (EDS). The results of the degradation experiments indicated a predominantly better absorption capacity of the samples with a porous structure compared to the full structure. At the same time, the blend containing a higher concentration of OLA exhibited enhanced pH stability over the evaluation period, maintaining relatively constant pH values before experiencing a minor decline at the end of the study. This observation indicates that the increased presence of the plasticizer may provide a buffering effect, effectively mitigating the acidification associated with material degradation.

Parametric identification of coefficients for a model of fatigue stiffness degradation of a composite material

The problem of finding the fatigue characteristics of a composite material based on test results is considered. The results of endurance tests of unidirectional polymer composite materials with different initial stiffness, breaking stress and working cycle stress were used as the initial data. As a mathematical model of stiffness degradation, a nonlinear ordinary differential equation with five unknown parameters is used, reflecting characteristic changes in the properties of the material. It is required to find such parameter values that the solution of the differential equation should describe the available test results with sufficient accuracy. The solution procedure is reduced to the problem of optimizing the objective function, the value of which characterizes the achieved accuracy. As optimization methods, a method simulating the behavior of a flock of moths and a method of sequential reduction of the search set were used. A step-by-step algorithm for finding unknown model parameters is proposed, and numerical results of processing input data containing information on changing the elasticity modulus of the composite material in the course of applying load cycles are presented.

Development of antioxidant arabinoxylan-tea polyphenol composite films for enhanced preservation of fresh grapes

In this study, arabinoxylan (AX) was used as a substrate, and tea polyphenol (TP) as a functional additive to create degradable, non-polluting, and antioxidant packaging materials. The effects of different TP concentrations on light transmittance and antioxidant activity of the AX-TP composite films were analyzed. The colors of the films gradually deepened with increasing TP content. The maximum scavenging rate of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals using the AX-TP composite film solution of 59.13 ± 2.19 % was achieved at the TP concentration of 2.0 %. AX-TP composite films with different TP concentrations were applied to the surfaces of grapes, and the sensory quality, shriveling and decay rates, titratable acid, and weight loss rate of grapes during storage were evaluated using data from different experimental groups. The AX-TP composite films coated on grapes reduced the transpiration of water in the fruit and delayed grape spoilage, demonstrating an excellent preservation effect. These results show that AX-TP composite films increase the shelf life of fresh grapes.

Elevated Netrin-4 Expression and Its Action in Infrapatellar Fat Pad.

Knee osteoarthritis (KOA) is a degenerative joint disease characterized by inflammation and cartilage degradation. The infrapatellar fat pad (IFP), located beneath the patella within the knee joint, serves as a key anatomical structure involved in cushioning and supporting the knee. It is also an active endocrine organ that secretes various bioactive substances, potentially influencing the local inflammatory environment and contributing to KOA pathogenesis. Netrin-4 (NTN4), a protein primarily known for its role in neuronal guidance, has been implicated in various non-neuronal functions, including inflammatory processes and tissue remodeling. This study aims to explore the involvement of NTN4 in KOA, focusing on its expression in the IFP and its potential impact on disease progression. This study involved 82 patients with radiographically confirmed KOA undergoing total knee arthroplasty (TKA). The correlation between NTN4 expression and OA pathology, including Kellgren-Lawrence (K/L) grades, was investigated. NTN4-expressing cells were identified in the stromal vascular fraction, including fibroblastic, hematopoietic, and endothelial cells of the IFP. To elucidate the molecular effects of NTN4, RNA sequencing (RNA-seq) was performed on fibroblastic cells treated with recombinant NTN4. Subsequent quantitative PCR (qPCR) was used to validate the RNA-seq findings. NTN4 expression was significantly elevated in the IFP of patients with advanced KOA (K/L grades 3 and 4) compared to those with early-stage disease (K/L grade 2). Higher NTN4 expression was found in fibroblastic cells, and RNA-seq analysis revealed upregulation of genes associated with pro-inflammatory pathways, including IL-17 and TNF-α signaling, and matrix degradation. Notably, genes including IL6, MMP1, CXCL1, and CXCL8 were significantly elevated, as confirmed by qPCR, indicating NTN4's role in promoting an inflammatory and catabolic environment. Our findings suggest that NTN4 plays a significant role in the pathogenesis of KOA by promoting inflammation and matrix degradation within the IFP. Although NTN4 expression was not directly correlated with clinical symptoms, its elevated expression in fibroblastic cells and influence on inflammatory and degradative pathways suggest a potential mechanism for exacerbating joint damage. Targeting NTN4 could offer a novel therapeutic approach to mitigating inflammation and slowing disease progression in KOA, ultimately improving patient outcomes. Further research is needed to clarify NTN4's specific roles and therapeutic potential in OA management.

Experimental insights on iron-based alloys corrosion in water cooled loops

This paper presents experimental findings on the behavior of iron-based alloys in environmental conditions typical of nuclear fusion technology, specifically focusing on material degradation, which is a critical aspect for the water cooling system of EU DEMO breeding blankets. The experimental campaign investigates potassium hydroxide’s role as an alkalizing agent, testing various concentrations to assess its impact on corrosion resistance. Additionally, it examines how oxygen levels affect localized corrosion development, which is crucial for mitigating corrosion risks in fusion applications. Seven 1000-hour tests were conducted to determine optimal conditions for corrosion reduction. Findings include identifying an oxygen concentration threshold to prevent piping cracking on EUROFER97 specimens.

Persistent effects of di-n-butyl phthalate on liver transcriptome: Impaired energy and lipid metabolic pathways

The environmental contaminant dibutyl phthalate (DBP) is reported to be hepatotoxic, but the underlying molecular pathways and pathological processes remain unclear. Here we used RNA-sequencing to characterize persistent hepatic transcriptional effects one week after the conclusion of five weeks oral exposure to 10 mg/kg/day or 100 mg/kg/day DBP in adult male mice. The exploratory transcriptome analysis demonstrated five differentially expressed genes (DEGs) in the 10 mg/kg/day group and 13 in the 100 mg/kg/day group. Gene Set Enrichment Analysis (GSEA), which identifies affected biological pathways rather than focusing solely on individual genes, revealed nine significantly enriched Reactome pathways shared by both DBP treatment groups. Additionally, we found 54 upregulated and one downregulated Reactome pathways in the 10 mg/kg/day DBP group, and 29 upregulated and 13 downregulated pathways in the 100 mg/kg/day DBP group. DBP exposure disrupted several key biological processes, including protein translation, protein folding, apoptosis, Hedgehog signaling, degradation of extracellular matrix and alterations in the energy/lipid metabolism. Subsequent liver tissue analysis confirmed that DBP exposure induced tissue disorganization, oxidative stress, lipid accumulation, increased TNF-α, ATP and glucokinase levels, and affected key metabolic proteins, predominantly in a dose-response manner. Overall, the results show that DBP can cause hepatic stress and damage and suggest a potential role for DBP in the development of non-alcoholic fatty liver disease, the most prevalent liver disease worldwide.

M proteins of group A Streptococcus bind hyaluronic acid via arginine-arginine/serine-arginine motifs.

Tissue injury, including extracellular matrix (ECM) degradation, is a hallmark of group A Streptococcus (GAS) skin infection and is partially mediated by M proteins which possess lectin-like properties. Hyaluronic acid is a glycosaminoglycan enriched in the cutaneous ECM, yet an interaction with M proteins has yet to be explored. This study revealed that hyaluronic acid binding was conserved across phylogenetically diverse M proteins, mediated by RR/SR motifs predominantly localized in the C repeat region. Keratinocyte wound healing was decreased through the recruitment of hyaluronic acid by M proteins in an M type-specific manner. GAS strains 5448 (M1 serotype) and ALAB49 (M53 serotype) also bound hyaluronic acid via M proteins, but hyaluronic acid could increase bacterial adherence independently of M proteins. The identification of host-pathogen mechanisms that affect ECM composition and cell repair responses may facilitate the development of nonantibiotic therapeutics that arrest GAS disease progression in the skin.

Molybdenum nanodots act as antioxidants for photothermal therapy osteoarthritis

Osteoarthritis (OA) manifests as the degradation of cartilage and remodeling of subchondral bone. Restoring homeostasis within the joint is imperative for alleviating OA symptoms. Current interventions primarily target singular aspects, such as anti-aging, inflammation inhibition, free radical scavenging, and regeneration of cartilage and subchondral bone. Herein, we developed molybdenum nanodots (MNDs) as bionic photothermal nanomaterials to mimic the antioxidant synthase to concurrently protected cartilage and facilitate subchondral bone regeneration. With near-infrared (NIR) irradiation, MNDs effectively eliminate reactive oxygen and nitrogen species (ROS/RNS) from OA chondrocytes, thereby reversed mitochondrial dysfunction, mitigating chondrocyte senescence, and simultaneously suppresses inflammation, hence preserving the inherent homeostasis between cartilage matrix synthesis and degradation while circumventing safety concerns. RNA sequencing of OA chondrocytes treated with MNDs-NIR revealed the reinstatement of chondrocyte functionality, activation of antioxidant enzymes, anti-aging properties, and regulation of inflammation. NIR irradiation induces thermogenesis and synergistically promotes subchondral bone regeneration via MNDs, as validated through histological assessments and microcomputed tomography (Micro-CT) scans. MNDs-NIR effectively attenuate cellular senescence and inhibit inflammation in vivo, while also remodeling mitochondrial dynamics by upregulating fusion proteins and inhibiting fission proteins, thereby regulating the oxidative stress microenvironment. Additionally, MNDs-NIR exhibited remarkable therapeutic effects in alleviating articular cartilage degeneration in an OA mouse model, evidenced by a 1.67-fold reduction in subchondral bone plate thickness, an 88.57 % decrease in OARSI score, a 5.52-fold reduction in MMP13 expression, and a 6.80-fold increase in Col II expression. This novel disease-modifying approach for OA utilizing MNDs-NIR offers insight and a paradigm for improving mitochondrial dysfunction by regulating the accumulation of mitochondrial ROS and ultimately alleviating cellular senescence. Moreover, the dual-pronged therapeutic approach of MNDs-NIR, which addresses both cartilage erosion and subchondral bone lesions in OA, represents a highly promising strategy for managing OA.

Nano Material Innovation in Enhancing Corrosion Resistance of Offshore Structures

Offshore structures are constantly exposed to the corrosive marine environment, causing significant material degradation and potentially jeopardizing structural integrity. This research explores recent innovations in nanomaterial technology to improve the corrosion resistance of offshore structures. The main focus is given to the development of nano-composite coatings incorporating metal oxide nanoparticles and carbon nanotubes. An electrophoretic deposition method was used to apply the coatings on steel substrates, followed by characterization using scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). Results showed a significant improvement in corrosion resistance, with the nano-composite coatings exhibiting a reduction in corrosion rate of up to 85% compared to conventional coatings. In addition, these coatings exhibited superior adhesion and abrasion resistance in simulated extreme marine conditions. These findings highlight the great potential of nanomaterials in extending the service life and improving the reliability of offshore structures, with important implications for the oil and gas and offshore renewable energy industries.

SbSeI for high-efficient photocatalytic degradation of multiple pollutants

Photocatalytic degradation is an effective technology for degrading water pollution that plays a significant role in environmental remediation. Ternary 2D ternary V-VI-VIIA semiconductors are ideal candidates for photocatalytic degradation of pollutants due to effective light absorption and high charge carrier mobility. In this work, high-quality SbSeI crystals were prepared using the chemical vapor transport (CVT) method and their photocatalytic degradation performance for multiple pollutants was studied. SbSeI exhibits excellent photocatalytic performance in the degradation of potassium dichromate (Cr (VI)), rhodamine B (RhB), tetracycline hydrochloride (TC-HCl) and methyl orange (MO). More than 98% of Cr (VI) and RhB can be removed after irradiation with an Xe lamp for 10 min and 40 min, respectively. The capture experiments and electron spin resonance results indicated that ·O2− plays a major role in reducing Cr (VI), while h+ plays a primary role in the degradation of MO, RhB and TC-HCl. Interestingly, the degradation rate of Cr (VI) is 1.3 times higher than that of a single pollutant system, and the degradation rate of RhB is 1.6 times higher, due to the enhanced separation and utilization of holes and electrons. The results demonstrate that SbSeI is a potential photocatalytic degradation material.

A review on rheological approaches as a perfect tool to monitor thermal degradation of biodegradable polymers

AbstractThis review provides an in-depth analysis of the thermal degradation of biodegradable polymers through rheological methods. Focusing on key techniques such as time sweep tests, frequency sweep tests, and nonlinear rheological analyses gained at higher shear tests, the review highlights how these approaches offer critical insights into polymer stability and degradation kinetics. It entails an understanding of how molecular weight reduction, a common degradation mechanism, significantly impacts the performance of biodegradable polymers, and how the use of appropriate fillers can enhance thermal stability by mitigating chain scission. The review also discusses the application of the Arrhenius equation in modelling thermal degradation, helping predict degradation rates and optimize processing conditions. Time sweep tests are particularly emphasized for their ability to monitor polymer stability under various environmental conditions, while frequency sweep tests provide insights into the effects of processing/thermal history on material degradation. Tests at higher shear rates, which simulate real-world processing conditions such as extrusion and injection moulding, are explored for their role in understanding how processing-induced shear forces accelerate polymer degradation. Various biodegradable polymers are considered in this review, with polylactic acid (PLA) being the dominant polymer studied across most research, providing a clear picture of its degradation behaviour and strategies for enhancing its thermal stability. Therefore, it is expected that this review will be a comprehensive guide for researchers and engineers looking to optimize the thermal stability and performance of biodegradable polymers in various industrial applications. Graphical abstract

The active ingredient of Evodia rutaecarpa reduces inflammation in knee osteoarthritis rats through blocking calcium influx and NF-κB pathway.

Chronic inflammation significantly contributes to the progression of osteoarthritis (OA), and an anti-inflammatory small molecule derived from medicinal herbs could be a potential drug candidate for OA. Herein, we investigated the function and mechanism of Evodiamine (EAE), the active ingredient from Evodia rutaecarpa, in chondrocytes and macrophages in vitro and in vivo. The cytotoxicity of EAE was determined using an MTT assay. And the anti-inflammatory and anti-extracellular matrix (ECM) degradation effects of EAE were investigated using qRT-PCR, western blot (WB), immunofluorescence (IF). Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Fluo-4AM, IF and AutoDock were used to elucidate the molecular mechanisms and signalling pathways of the reducing-inflammatory properties of EAE on chondrocytes in vitro. Moreover, the effect of EAE on macrophage polarization was detected by IF and flow cytometry (FC). Ultimately, we explored the in vivo therapeutic efficacy of EAE in an anterior cruciate ligament transection (ACLT)-induced OA model. The finding demonstrated that EAE blocked the phosphorylation of IKBα and Ca2+ influx, thereby curbing inflammation and ECM degradation. Additionally, EAE can prevent the polarization towards the M1 phenotype. Thus, our findings suggest that EAE has great potential as a therapeutic drug for the treatment of OA.