PDZK1 protects against mechanical overload-induced chondrocyte senescence and osteoarthritis by targeting mitochondrial function

Mechanical overloading and aging are two essential factors for osteoarthritis(OA)development.Mitochondria have been identified as a mechano-transducer situated between extracellular mechanical signals and chondrocyte biology,but their roles and the associated mechanisms in mechanical stress-associated chondrocyte senescence and OA have not been elucidated.

Controlled-release hydrogel loaded with magnesium-based nanoflowers synergize immunomodulation and cartilage regeneration in tendon-bone healing

Tendon-bone interface injuries pose a significant challenge in tissue regeneration,necessitating innovative approaches.Hydrogels with integrated supportive features and controlled release of therapeutic agents have emerged as promising candidates for the treatment of such injuries.In this study,we aimed to develop a temperature-sensitive composite hydrogel capable of providing sustained release of magnesium ions(Mg^(2+)).We synthesized magnesium-Procyanidin coordinated metal polyphenol nanoparticles(Mg-PC)through a self-assembly process and integrated them into a two-component hydrogel.The hydrogel was composed of dopamine-modified hyaluronic acid(Dop-HA)and F127.To ensure controlled release and mitigate the“burst release”effect of Mg^(2+),we covalently crosslinked the Mg-PC nanoparticles through coordination bonds with the catechol moiety within the hydrogel.This crosslinking strategy extended the release window of Mg^(2+)concentrations for up to 56 days.The resulting hydrogel(Mg-PC@Dop-HA/F127)exhibited favorable properties,including injectability,thermosensitivity and shape adaptability,making it suitable for injection and adaptation to irregularly shaped supraspinatus implantation sites.Furthermore,the hydrogel sustained the release of Mg^(2+)and Procyanidins,which attracted mesenchymal stem and progenitor cells,alleviated inflammation,and promoted macrophage polarization towards the M2 phenotype.Additionally,it enhanced collagen synthesis and mineralization,facilitating the repair of the tendon-bone interface.By incorporating multilevel metal phenolic networks(MPN)to control ion release,these hybridized hydrogels can be customized for various biomedical applications.

Towards catalytic reactions of Cu single-atom catalysts:Recent progress and future perspective

One of the urgent and challenging topics in diversified sustainable energy conversion is the development of high-performance,low-cost,and well durable catalysts.Cu single-atom catalysts(SACs)have become promising catalysts for diversified sustainable energy conversion due to their capability to maximize the utilization efficiency,acquire modulated electronic structure and optimized binding strength with intermediates.In this review,we have provided an interview of the recent progress achieved in the field of electrocatalysis,photocatalysis,and heterogeneous reaction based on Cu SACs.Started by this review,we have summarized some advanced synthetic strategies for the construction of Cu SACs.Subsequently,the performance-improving strategies are discussed in terms of the coordination environments of the reaction center,reaction mechanism and selectivity,based on free energy diagram and electron structure analysis.Finally,the remaining issues,challenges,and opportunities of Cu SACs are also provided,affording a perspective for future studies.This review not only offers us a deep understanding on the catalytic mechanism of Cu SACs for energy conversion,but also encourages more endeavors in prompting their practical application.

Synergistic rheumatoid arthritis therapy by interrupting the detrimental feedback loop to orchestrate hypoxia M1 macrophage polarization using an enzyme-catalyzed nanoplatform

Rapid and efficient tendon fixation to a bone following trauma or in response to degenerative processes can be facilitated using a tendon anchoring device.Osteomimetic biomaterials,and in particular,bio-resorbable polymer composites designed to match the mineral phase content of native bone,have been shown to exhibit osteoinductive and osteoconductive properties in vivo and have been used in bone fixation for the past 2 decades.In this study,a resorbable,bioactive,and mechanically robust citrate-based composite formulated from poly(octamethylene citrate)(POC)and hydroxyapatite(HA)(POC-HA)was investigated as a potential tendon-fixation biomaterial.In vitro analysis with human Mesenchymal Stem Cells(hMSCs)indicated that POC-HA composite materials supported cell adhesion,growth,and proliferation and increased calcium deposition,alkaline phosphatase production,the expression of osteogenic specific genes,and activation of canonical pathways leading to osteoinduction and osteoconduction.Further,in vivo evaluation of a POC-HA tendon fixation device in a sheep metaphyseal model indicates the regenerative and remodeling potential of this citrate-based composite material.Together,this study presents a comprehensive in vitro and in vivo analysis of the functional response to a citrate-derived composite tendon anchor and indicates that citrate-based HA composites offer improved mechanical and osteogenic properties relative to commonly used resorbable tendon anchor devices formulated from poly(L-co-D,l-lactic acid)and tricalcium phosphate PLDLA-TCP.

Anti-oxidant anti-inflammatory and antibacterial tannin-crosslinked citrate-based mussel-inspired bioadhesives facilitate scarless wound healing

The revolutionary role of tissue adhesives in wound closure,tissue sealing,and bleeding control necessitates the development of multifunctional materials capable of effective and scarless healing.In contrast to the use of traditionally utilized toxic oxidative crosslinking initiators(exemplified by sodium periodate and silver nitrate),herein,the natural polyphenolic compound tannic acid(TA)was used to achieve near instantaneous(<25s),hydrogen bond mediated gelation of citrate-based mussel-inspired bioadhesives combining anti-oxidant,anti-inflammatory,and antimicrobial activities(3A-TCMBAs).The resulting materials were self-healing and possessed low swelling ratios(<60%)as well as considerable mechanical strength(up to~1.0 MPa),elasticity(elongation~2700%),and adhesion(up to 40 kPa).The 3A-TCMBAs showed strong in vitro and in vivo anti-oxidant ability,favorable cytocompatibility and cell migration,as well as photothermal antimicrobial activity against both Staphylococcus aureus and Escherichia coli(>90%bacterial death upon near-infrared(NIR)irradiation).In vivo evaluation in both an infected full-thickness skin wound model and a rat skin incision model demonstrated that 3A-TCMBAs+NIR treatment could promote wound closure and collagen deposition and improve the collagen Ⅰ/Ⅲ ratio on wound sites while simultaneously inhibiting the expression of pro-inflammatory cytokines.Further,phased angiogenesis was observed via promotion in the early wound closure phases followed by inhibition and triggering of degradation&remodeling of the extracellular matrix(ECM)in the late stage(supported by phased CD31(platelet endothelial cell adhesion molecule-1)PDGF(platelet-derived growth factor)and VEGF(vascular endothelial growth factor)expression as well as elevated matrix metalloprotein-9(MMP-9)expression on day 21),resulting in scarless wound healing.The significant convergence of material and bioactive properties elucidated above warrant further exploration of 3A-TCMBAs as a significant,new class of bioadhesive.

后合成静电吸附辅助制备高效Fe-N-C单原子氧还原催化剂用于锌-空气电池

设计和制备高效的非铂族催化剂对锌-空气电池的大规模应用至关重要.本文采用简单的后合成静电吸附策略制备了Fe-N-C单原子催化剂(Fe-SA/N-C).其中,Fe原子与相邻的氮原子形成Fe-N4活性位点并锚定在三维多孔碳上.该催化剂在0.1 mol L^(-1)KOH (E_(1/2)=0.92 V)和0.5 mol L^(-1)H_(2)SO_(4)(E_(1/2)=0.77 V)中均表现出优异的氧化还原活性,性能优于商业Pt/C催化剂(0.1 mol L^(-1)KOH,E_(1/2)=0.85 V;0.5 mol L^(-1)H_(2)SO_(4),E_(1/2)=0.79 V).此外,以Fe-SA/N-C作为阴极催化剂自组装的液体锌-空气电池具有优异的放电比容量和峰值功率密度,优于商业Pt/C催化剂.密度泛函理论计算结果表明,石墨化氮掺杂的Fe-N4位点能有效提高ORR中间产物的活化程度,降低速率决定步骤的能垒.本工作对非铂族催化剂的实验制备和理论研究提出了新的见解,为锌-空气电池中使用的非铂族催化剂的合理设计提供了一般策略.

Zn_(x)Zr/HZSM-5 as efficient catalysts for alkylation of benzene with carbon dioxide

Alkylation of benzene with carbon dioxide and hydrogen to produce toluene and xylene could increase the added-value of surplus benzene as well as relieve environmental problems like green-house effect.In this work,the alkylation benzene with carbon dioxide and hydrogen reaction was proceeded by using the mixture of zinc-zirconium oxide and HZSM-5 as bifunctional catalyst.The equivalent of Zn/Zr=1 displays the best catalytic performance at 425℃ and 3.0 MPa,and benzene conversion reaches 42.9%with a selectivity of 90%towards toluene and xylene.Moreover,the carbon dioxide conversion achieves 23.3%and the carbon monoxide selectivity is lower than 35%,indicating that more than 50%carbon dioxide has been effectively incorporated into the target product,which is the best result as far as we know.Combined with characterizations,it indicated that the Zn and Zr formed a solid solution under specific conditions(Zn/Zr=1).The as-formed solid solution not only possesses a high surface area but also provides a large amount of oxygen vacancies.Additionally,the bifunctional catalyst has excellent stabilities that could keep operating without deactivation for at least 80 h.This work provides promising industrial applications for the upgrading of aromatics.

Abscisic acid-mediated cytosolic Ca^(2+) modulates triterpenoid accumulation of Ganoderma lucidum

Ganoderma lucidum is a mushroom widely used for its edible and medicinal properties.Primary bioactive constituents of G.lucidum are ganoderic triterpenoids(GTs),which exhibit important pharmacological activity.Abscisic acid(ABA),a plant hormone,is associated with plant growth,development,and stress responses.ABA can also affect the growth,metabolism,and physiological activities of different fungi and participates in the regulation of the tetracyclic triterpenes of some plants.Our findings indicated that ABA treatment promoted GT accumulation by regulating the gene expression levels(squalene synthase(sqs),3-hydroxy-3-methylglutaryl-CoA reductase(hmgr),and lanosterol synthase(ls)),and also activated cytosolic Ca2 channels.Furthermore,under ABA mediation.