Biomass-enhanced Janus sponge-like hydrogel with salt resistance and highstrength for efficient solar desalination

Interfacial solar-driven evaporation technology shows great potential in the field of industrial seawater desalination, and the development ofefficient and low-cost evaporation materials is key to achieving large-scale applications. Hydrogels are considered to be promising candidates;however, conventional hydrogel-based interfacial solar evaporators have difficulty in simultaneously meeting multiple requirements, including ahigh evaporation rate, salt resistance, and good mechanical properties. In this study, a Janus sponge-like hydrogel solar evaporator (CPAS) withexcellent comprehensive performance was successfully constructed. The introduction of biomass agar (AG) into the polyvinyl alcohol (PVA)hydrogel backbone reduced the enthalpy of water evaporation, optimized the pore structure, and improved the mechanical properties. Meanwhile, by introducing hydrophobic fumed nano-silica aerogel (SA) and a synergistic foaming-crosslinking process, the hydrogel spontaneouslyformed a Janus structure with a hydrophobic surface and hydrophilic bottom properties. Based on the reduction of the evaporation enthalpy andthe modulation of the pore structure, the CPAS evaporation rate reached 3.56 kg m^(-2) h^(-1) under one sun illumination. Most importantly, owingto the hydrophobic top surface and 3D-interconnected porous channels, the evaporator could work stably in high concentrations of salt-water(25 wt% NaCl), showing strong salt resistance. Efficient water evaporation, excellent salt resistance, scalable preparation processes, and low-costraw materials make CPAS extremely promising for practical applications.

High drug loading hydrophobic cross-linked dextran microspheres as novel drug delivery systems for the treatment of osteoarthritis

Drug delivery via intra-articular(IA)injection has proved to be effective in osteoarthritis(OA)therapy,limited by the drug efficiency and short retention time of the drug delivery systems(DDSs).Herein,a series of modified cross-linked dextran(Sephadex,S0)was fabricated by respectively grafting with linear alkyl chains,branched alkyl chains or aromatic chain,and acted as DDSs after ibuprofen(Ibu)loading for OA therapy.This DDSs expressed sustained drug release,excellent anti-inflammatory and chondroprotective effects both in IL-1βinduced chondrocytes and OA joints.Specifically,the introduction of a longer hydrophobic chain,particularly an aromatic chain,distinctly improved the hydrophobicity of S0,increased Ibu loading efficiency,and further led to significantly improving OA therapeutic effects.Therefore,hydrophobic microspheres with greatly improved drug loading ratio and prolonged degradation rates show great potential to act as DDSs for OA therapy.

Pathological mechanisms and therapeutic outlooks for arthrofibrosis

Arthrofibrosis is a fibrotic joint disorder that begins with an inflammatory reaction to insults such as injury,surgery and infection.Excessive extracellular matrix and adhesions contract pouches,bursae and tendons,cause pain and prevent a normal range of joint motion,with devastating consequences for patient quality of life.Arthrofibrosis affects people of all ages,with published rates varying.The risk factors and best management strategies are largely unknown due to a poor understanding of the pathology and lack of diagnostic biomarkers.However,current research into the pathogenesis of fibrosis in organs now informs the understanding of arthrofibrosis.The process begins when stress signals stimulate immune cells.The resulting cascade of cytokines and mediators drives fibroblasts to differentiate into myofibroblasts,which secrete fibrillar collagens and transforming growth factor-β(TGF-β).Positive feedback networks then dysregulate processes that normally terminate healing processes.We propose two subtypes of arthrofibrosis occur:active arthrofibrosis and residual arthrofibrosis.In the latter the fibrogenic processes have resolved but the joint remains stiff.The best therapeutic approach for each subtype may differ significantly.Treatment typically involves surgery,however,a pharmacological approach to correct dysregulated cell signalling could be more effective.Recent research shows that myofibroblasts are capable of reversing differentiation,and understanding the mechanisms of pathogenesis and resolution will be essential for the development of cell-based treatments.Therapies with significant promise are currently available,with more in development,including those that inhibit TGF-βsignalling and epigenetic modifications.This review focuses on pathogenesis of sterile arthrofibrosis and therapeutic treatments.

NIR-enhanced Pt single atom/g-C_(3)N_(4)nanozymes as SOD/CAT mimics to rescue ATP energy crisis by regulating oxidative phosphorylation pathway for delaying osteoarthritis progression

Osteoarthritis(OA)progresses due to the excessive generation of reactive oxygen and nitrogen species(ROS/RNS)and abnormal ATP energy metabolism related to the oxidative phosphorylation pathway in the mitochondria.Highly active single-atom nanozymes(SAzymes)can help regulate the redox balance and have shown their potential in the treatment of inflammatory diseases.In this study,we innovatively utilised ligand-mediated strategies to chelate Pt^(4+)with modified g-C_(3)N_(4)byπ-πinteraction to prepare g-C_(3)N_(4)-loaded Pt single-atom(Pt SA/C_(3)N_(4))nanozymes that serve as superoxide dismutase(SOD)/catalase(CAT)mimics to scavenge ROS/RNS and regulate mitochondrial ATP production,ultimately delaying the progression of OA.Pt SA/C_(3)N_(4)exhibited a high loading of Pt single atoms(2.45 wt%),with an excellent photothermal conversion efficiency(54.71%),resulting in tunable catalytic activities under near-infrared light(NIR)irradiation.Interestingly,the Pt-N_(6) active centres in Pt SA/C_(3)N_(4)formed electron capture sites for electron holes,in which g-C_(3)N_(4)regulated the d-band centre of Pt,and the N-rich sites transferred electrons to Pt,leading to the enhanced adsorption of free radicals and thus higher SOD-and CAT-like activities compared with pure g-C_(3)N_(4)and g-C_(3)N_(4)-loaded Pt nanoparticles(Pt NPs/C_(3)N_(4)).Based on the use of H_(2)O_(2)-induced chondrocytes to simulate ROS-injured cartilage in vitro and an OA joint model in vivo,the results showed that Pt SA/C_(3)N_(4)could reduce oxidative stress-induced damage,protect mitochondrial function,inhibit inflammation progression,and rebuild the OA microenvironment,thereby delaying the progression of OA.In particular,under NIR light irradiation,Pt SA/C_(3)N_(4)could help reverse the oxidative stress-induced joint cartilage damage,bringing it closer to the state of the normal cartilage.Mechanistically,Pt SA/C_(3)N_(4)regulated the expression of mitochondrial respiratory chain complexes,mainly NDUFV2 of complex 1 and MT-ATP6 of ATP synthase,to reduce ROS/RNS and promote ATP production.This study provides novel insights into the design of artificial nanozymes for treating oxidative stress-induced inflammatory diseases.

Mitochondrial-targeting Mn_(3)O_(4)/UIO-TPP nanozyme scavenge ROS to restore mitochondrial function for osteoarthritis therapy

Excessive reactive oxygen species(ROS)-induced mitochondrial damage has impact on osteoarthritis(OA).Nanozyme mimics as natural enzyme alternatives to scavenge excessive ROS has offered a promising strategy for OA therapy.Herein,we reported a novel mitochondrial-targeting Mn_(3)O_(4)/UIO-TPP nanozyme using metal-organic frameworks with loaded Mn_(3)O_(4)as the enzyme-like active core combining mitochondria-targeting triphenylphosphine(TPP)groups to serve as ROS scavengers for therapy of OA.With sequential catalysis of superoxide dismutase-like,catalase(CAT)-like,and hydroxyl radical(·OH)scavenging potentials,the nanozyme can target mitochondria by crossing subcellular barriers to effectively eliminate ROS to restore mitochondrial function and inhibit inflammation and chondrocyte apoptosis.It also has favorable biocompatibility and biosafety.Based on anterior cruciate ligament transection-induced OA joint models,this mitochondrial-targeting nanozyme effectively mitigated the inflammatory response with the Pelletier score reduction of 49.9%after 8-week therapy.This study offers a prospective approach to the design of nanomedicines for ROS-related diseases.

Natural Morin-Based Metal Organic Framework Nanoenzymes Modulate Articular Cavity Microenvironment to Alleviate Osteoarthritis

Osteoarthritis(OA)is always characterized as excessive reactive oxygen species(ROS)inside articular cavity.Mimicking natural metalloenzymes with metal ions as the active centers,stable metal organic framework(MOF)formed by natural polyphenols and metal ions shows great potential in alleviating inflammatory diseases.Herein,a series of novel copper-morin-based MOF(CuMHs)with different molar ratios of Cu^(2+)and MH were employed to serve as ROS scavengers for OA therapy.As a result,CuMHs exhibited enhanced dispersion in aqueous solution,improved biocompatibility,and efficient ROS-scavenging ability compared to MH.On the basis of H_(2)O_(2)-stimulated chondrocytes,intracellular ROS levels were efficiently declined and cell death was prevented after treated by Cu_(6)MH(Cu^(2+)and MH molar ratio of 6:1).Meanwhile,Cu_(6)MH also exhibited efficient antioxidant and anti-inflammation function by down-regulating the expression of IL6,MMP13,and MMP3,and up-regulating cartilage specific gene expression as well.Importantly,Cu_(6)MH could repair mitochondrial function by increasing mitochondrial membrane potential,reducing the accumulation of calcium ions,as well as promoting ATP content production.In OA joint model,intra-articular(IA)injected Cu_(6)MH suppressed the progression of OA.It endowed that Cu_(6)MH might be promising nanoenzymes for the prevention and treatment of various inflammatory diseases.

LiF@SiO2 nanocapsules for controlled lithium release and osteoarthritis treatment

Electrolytes can be taken orally or intravenously as supplements or thera- peutics. However, their therapeutic window may exceed the serum toxicity threshold, making systemic delivery a poor option. Local injection is also not adequate due to rapid diffusion of electrolytes. Here, we solved this issue with a nanocapsule technolog~ comprising an electrolyte nanocrystal as the drug filling and a silica sheath to regulate drug release rates. In particular, we prepared LiF@SiO2 nanocapsules and investigated their potential as a delivery system for lithium, which was shown in recent studies to be an effective therapeutic agent for osteoarthritis （OA）. We demonstrated that LiF@SiO2 can extend lithium release time from minutes to more than 60 h. After intra- articular （i.a.） injection into a rat OA model, the nanocapsules reduced the Osteoarthritis Research Society International （OARSI） score by 71% in 8 weeks while inducing no systemic toxicity. Our study opens new doors for improved delivery of electrolyte therapeutics, which have rarely been studied in the past.

Clean and effective removal of Cl(-I)from strongly acidic wastewater by PbO_(2)

Recycling strongly acidic wastewater as diluted H_(2)SO_(4) after contaminants contained being removed was previously proposed,however,Cl(-I),a kind of contaminant contained in strongly acidic wastewater,is difficult to remove,which severely degrades the quality of recycled H_(2)SO_(4).In this study,the removal of Cl(-I)using PbO_(2) was investigated and the involved mechanisms were explored.The removal efficiency of Cl(-I)reached 93.38%at 50℃ when PbO_(2)/Cl(-I)mole ratio reached 2:1.The identification of reaction products shows that Cl(-I)was oxidized to Cl_(2),and PbO_(2) was reduced to PbSO_(4).Cl_(2) was absorbed by NaOH to form NaClO,which was used for the regeneration of PbO_(2) from the generated PbSO_(4).Cl(-I)was removed through two pathways,i.e.,surface oxidation and•OH radical oxidation.•OH generated by the reaction of PbO_(2) and OH−plays an important role in Cl(-I)removal.The regenerated PbO_(2) had excellent performance to remove Cl(-I)after six-time regeneration.This study provided an in-depth understanding on the effective removal of Cl(-I)by the oxidation method.

Natural lotus root-based scaffolds for bone regeneration

A high incidence of bone defects and the limitation of autologous bone grafting require 3 D scaffolds for bone repair. Compared with synthetic materials, natural edible materials possess outstanding advantages in terms of biocompatibility, bioactivities and low manufacturing cost for bone tissue engineering. In this work, attracted by the natural porous/fabric structure, good biocompatibility and bioactivities of the lotus root, the lotus root-based scaffolds were fabricated and investigated their potential to serve as natural porous bone tissue engineering scaffolds. The results indicated that the lotus root-based scaffolds possess suitable natural microstructure, excellent biocompatibility and promising functions, such as antioxidant capacity and angiogenesis promotion. Remarkably, lotus root scaffolds showed encouraging possibility of bone tissue engineering while the mineralized lotus root could further improve the bone regeneration in vivo. All the results demonstrated the bone regeneration potential of lotus root-based scaffolds equipped with suitable natural architecture, excellent biocompatibility, specific bioactivities and low manufacturing cost.

Dimethylamino group modified polydopamine nanoparticles with positive charges to scavenge cell-free DNA for rheumatoid arthritis therapy

Excessive cell-free DNA(cfDNA)released by damaged or apoptotic cells can cause inflammation,impacting the progression of rheumatoid arthritis(RA).cfDNA scavengers,such as cationic nanoparticles(NPs),have been demonstrated as an efficient strategy for treating RA.However,most scavengers are limited by unfavorable biocompatibility and poor scavenging efficacy.Herein,by exploiting the favorable biocompatibility,biodegradability and bioadhesion of polydopamine(P),we modified P with dimethylamino groups to form altered charged DPs to bind negatively charged cfDNA for RA therapy.Results showed that DPs endowed with superior binding affinity of cfDNA and little cytotoxicity,which effectively inhibited lipopolysaccharide(LPS)stimulated inflammation in vitro,resulting in the relief of joint swelling,synovial hyperplasia and cartilage destruction in RA rats.Significantly,DPs with higher DS of bis dimethylamino group exhibited higher positive charge density and stronger cfDNA binding affinity,leading to excellent RA therapeutic effect among all of the treated groups,which was even close to normal rats.These finding provides a novel strategy for the treatment of cfDNA-associated diseases.