Harnessing nanomaterials for copper-induced cell death.

Copper (Cu), an essential micronutrient with redox properties, plays a pivotal role in a wide array of pathological and physiological processes across virtually all cell types. Maintaining an optimal copper concentration is critical for cellular survival: insufficient copper levels disrupt respiration and metabolism, while excess copper compromises cell viability, potentially leading to cell death. Similarly, in the context of cancer, copper exhibits a dual role: appropriate amount of copper can promote tumor progression and be an accomplice, yet beyond befitting level, copper can bring about multiple types of cell death, including autophagy, apoptosis, ferroptosis, immunogenic cell death, pyroptosis, and cuproptosis. These forms of cell death are beneficial against cancer progression; however, achieving precise copper regulation within tumors remains a significant challenge in the pursuit of effective cancer therapies. The emergence of nanodrug delivery systems, distinguished by their precise targeting, controlled release, high payload capacity, and the ability to co-deliver multiple agents, has revitalized interest in exploiting copper's precise regulatory capabilities. Nevertheless, there remains a dearth of comprehensive review of copper's bidirectional effects on tumorigenesis and the role of copper-based nanomaterials in modulating tumor progression. This paper aims to address this gap by elucidating the complex role in cancer biology and highlighting its potential as a therapeutic target. Through an exploration of copper's dualistic nature and the application of nanotechnology, this review seeks to offer novel insights and guide future research in advancing cancer treatment.

Insight into catalytic performance and reaction mechanism for toluene total oxidation over Cu-Ce supported catalyst.

Herein, three supported catalysts, CuO/Al2O3, CeO2/Al2O3, and CuO-CeO2/Al2O3, were synthesized by the convenient impregnation method to reveal the effect of CeO2 addition on catalytic performance and reaction mechanism for toluene oxidation. Compared with CuO/Al2O3, the T50 and T90 (the temperatures at 50% and 90% toluene conversion, respectively) of CuO-CeO2/Al2O3 were reduced by 33 and 39 °C, respectively. N2 adsorption-desorption experiment, XRD, SEM, EDS mapping, Raman, EPR, H2-TPR, O2-TPD, XPS, NH3-TPD, Toluene-TPD, and in-situ DRIFTS were conducted to characterize these catalysts. The excellent catalytic performance of CuO-CeO2/Al2O3 could be attributed to its strong copper-cerium interaction and high oxygen vacancies concentration. Moreover, in-situ DRIFTS proved that CuO-CeO2/Al2O3 promoted the conversion of toluene to benzoate and accelerated the deep degradation path of toluene. This work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.

Cu/TiO2 adsorbents modified by air plasma for adsorption-oxidation of H2S.

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42-) occupying the active sites on the surface and the inner pores of the adsorbents.

Efficiently directing differentiation and homing of mesenchymal stem cells to boost cartilage repair in osteoarthritis via a nanoparticle and peptide dual-engineering strategy.

Mesenchymal stem cells (MSCs) are expected to be useful therapeutics in osteoarthritis (OA), the most common joint disorder characterized by cartilage degradation. However, evidence is limited with regard to cartilage repair in clinical trials because of the uncontrolled differentiation and weak cartilage-targeting ability of MSCs after injection. To overcome these drawbacks, here we synthesized CuO@MSN nanoparticles (NPs) to deliver Sox9 plasmid DNA (favoring chondrogenesis) and recombinant protein Bmp7 (inhibiting hypertrophy). After taking up CuO@MSN/Sox9/Bmp7 (CSB NPs), the expressions of chondrogenic markers were enhanced while hypertrophic markers were decreased in response to these CSB-engineered MSCs. Moreover, a cartilage-targeted peptide (designated as peptide W) was conjugated onto the surface of MSCs via a click chemistry reaction, thereby prolonging the residence time of MSCs in both the knee joint cavity of mice and human-derived cartilage. In a surgery-induced OA mouse model, the NP and peptide dual-modified W-CSB-MSCs showed an enhancing therapeutic effect on cartilage repair in knee joints compared with other engineered MSCs after intra-articular injection. Most importantly, W-CSB-MSCs accelerated cartilage regeneration in damaged cartilage explants derived from OA patients. Thus, this new peptide and NPs dual engineering strategy shows potential for clinical applications to boost cartilage repair in OA using MSC therapy.

Alkyl effects on charge recombination in copper electrolyte-based dye-sensitized solar cells: Insights for targeted molecular design towards high performance.

Two quinoxaline dyes utilized in copper-electrolyte-based dye-sensitized solar cells (Cu-DSSCs) are theoretically investigated to analyze the impact of alkyl chains on dye performance. The investigation shows that ZS4, known for its record efficiency of up to 13.2 %, exhibits higher electron coupling and fewer binding sites for dye-[Cu(tmby)2]2+ interaction compared to ZS5. Contrary to common belief, alkyl chains are found to not only provide shielding but also hinder the interaction between dye and [Cu(tmby)2]2+ by influencing the optimal conformation of dyes, thereby impeding the charge recombination process. It is crucial to consider the influence of alkyl chains on dye conformation when discussing the relationship between dye structure and performance, rather than oversimplifying it as often done traditionally. Building on these findings, eight dyes are strategically designed by adjusting the position of the alkyl chain to further decrease charge recombination compared to ZS4. Theoretical evaluation of these dyes reveals that changing the alkyl chain on the nitrogen atom from 2-ethylhexyl (ZS4) to 1-hexylheptyl (D3-2) not only reduces the charge recombination rate but also enhances light harvesting ability. Therefore, D3-2 shows potential as a candidate for experimental synthesis of high-performance Cu-DSSCs with improved efficiency.

Developing an off-on fluorescence sensor based on red copper nanoclusters wrapped by sulfhydryl and polymer double ligands for sensitive detection of N-acetyl-L-cysteine.

N-acetyl-L-cysteine (NAC) as a class of thiols is commonly used in the treatment of lung diseases, detoxification and prevention of liver damage. In this paper, 4-mercaptobenzoic acid (4-MBA) coated and polyvinylpyrrolidone (PVP) attached copper nanoclusters (4-MBA@PVP-CuNCs) were successfully synthesized using a simple one-pot method with an absolute quantum yield of 10.98 %, and its synthetic conditions (like effects of single/double ligands and temperature) were studied intensively. Then Hg2+ could quench the fluorescence of the 4-MBA@PVP-CuNCs and its fluorescence was restored with the addition of NAC. Based on the above principles, an off-on switching system was established to detect NAC. That is, the 4-MBA@PVP-CuNCs-Hg probe was prepared by adding Hg2+ to switch off the fluorescence of the CuNCs by static quenching, and then NAC was added to switch on the fluorescence of the probe based on the chelation of NAC and Hg2+. Moreover, the effects of metal ion types and mercury ion doses for the probe construction were also further discussed. The method showed excellent linearity in the range of 0.05-1.25 µM and low detection limit of 16 nM. Meanwhile, good recoveries in real urine, tablets and pellets were observed, which proved the reliability of the method and provided a convenient, fast and sensitive method for NAC detection.

Mitigating Adverse Effects of Cu-containing Intrauterine Devices Using A Highly Biocompatible Cu-5Fe alloy.

Copper-containing intrauterine devices (Cu-IUD) are adopted by worldwide women for contraception with the advantages of long-term effectiveness, reversibility and affordability. However, adverse effects occur in the initial implantation stage of Cu-IUD in uterine because of the burst release of Cu2+. To minimize the burst release, in this study, we designed a series of Cu-Fe alloys with 0.5 wt%, 1 wt% and 5 wt% Fe and also further produced ultrafine grained (UFG) structure for these alloys via equal-channel angular pressing. The microstructures and properties of the coarse grained (CG) Cu, CG Cu-Fe alloys and UFG Cu-Fe alloys were systematically investigated, including grain structure and phase compositions, metallic ions release behavior, electrochemical corrosion performance, and in vitro cytotoxicity. With careful comparison and selection, we chose the CG Cu-5Fe and UFG Cu-5Fe for in vivo tests using rat model, including tissue biocompatibility, in vivo corrosion behavior, and contraceptive effectiveness. Moreover, the corrosion mechanism of the Cu-5Fe alloy and its improved biocompatibility was discussed. Both CG and UFG Cu-5Fe alloys exhibited dramatic suppression of Cu2+ release in simulated uterine fluid for the long-term immersion process. The in vivo tissue compatibility was significantly improved with both CG and UFG Cu-5Fe alloys implanted in the rats' uterine while the high contraceptive efficacy was well maintained. Due to the superior biocompatibility, the CG and UFG Cu-5Fe alloys can be the promising candidate material for Cu-IUD. STATEMENT OF SIGNIFICANCE: A highly biocompatible Cu-Fe alloy was designed and fabricated for Cu-containing intrauterine devices (Cu-IUD). With 5wt% Fe, the burst release of Cu2+ is inhibited due to the formed galvanic cell of Cu and Fe, resulting in earlier release of Fe3+. As Fe is the most abundant essential trace element of human body, it can mitigate the toxic effects of Cu2+, thus significantly improving both in vitro cell compatibility and in vivo tissue compatibility. More importantly, the Cu-5Fe alloy exhibits 100% contraceptive efficiency as the CG Cu, but with greatly reduced adverse effects to the uterus tissues. An advanced Cu-IUD can be developed using Cu-Fe alloys.

When Metal Complexes Evolve, and a Minor Species Is the Most Active: the Case of Bis(Phenanthroline)Copper in the Catalysis of Glutathione Oxidation and Hydroxyl Radical Generation.

Several copper-ligands, including 1,10-phenanthroline (Phen), have been investigated for anticancer purposes based on their capacity to bind excess copper (Cu) in cancer tissues and form redox active complexes able to catalyse the formation of reactive oxygen species (ROS), ultimately leading to oxidative stress and cell death. Glutathione (GSH) is a critical compound as it is highly concentrated intracellularly and can reduce and dissociate copper(II) from the ligand forming poorly redox-active copper(I)-thiolate clusters. Here we report that Cu-Phen2  speciation evolves in physiologically relevant GSH concentrations. Experimental and computational experiments suggest that at pH 7.4 mostly copper(I)-GSH clusters are formed, but a minor species of copper(I) bound to one Phen and forming ternary complexes with GSH (GS-Cu-Phen) is the redox active species, oxidizing quite efficiently GSH to GSSG and forming HO• radicals. This minor active species becomes more populated at lower pH, such as typical lysosomal pH 5, resulting in faster GSH oxidation and HO• production. Consistently, cell culture studies showed lower toxicity of Cu-Phen2 upon inhibition of lysosomal acidification. Overall, this study underscores that sub-cellular localisation can considerably influence the speciation of Cu-based drugs and that minor species can be the most redox- and biologically- active.

Planar Tetracoordinate Silicon in Si3Cu3- Cluster.

Photoelectron spectroscopy and theoretical calculations have identified the global minimum structure of the 16-valence electron Si3Cu3- cluster, which features a planar tetracoordinate silicon (ptSi) in a rhombic arrangement. The Si3 and Cu3 triangles are interconnected by an Si2/Cu2 edge, forming an ordered chain-like structure. Besides the conventional 2c-2e σ-bond connecting Si3 and Cu3, the stability of this cluster is reinforced by a delocalized 3c-2e σ-bond in Cu3 and a π-bond in Si3. Our study provides rare experimental confirmation of a planar hypercoordinate heavier Group 14 element, opening possibilities for exploring similar structures in two-dimensional materials.

Size-dependent Copper Nanoparticles Supported on Carbon Nanotubes with Balanced Cu+ and Cu0 Dual Sites for the Selective Hydrogenation of Ethylene Carbonate.

Cyclic carbonate hydrogenation offers an alternative for the efficient indirect CO2 utilization. In this study, a series of carbon nanotubes (CNTs) supported xCu/CNTs catalysts with different Cu loadings were fabricated using a convenient impregnation method, and exhibited excellent catalytic activity for the hydrogenation of ethylene carbonate to methanol and ethylene glycol. The structural and physicochemical properties revealed that acid treatment of CNTs resulted in plentiful oxygen-containing functional groups, providing sufficient anchoring sites for copper species. The calcination process conducted under an inert atmosphere resulted in the formation of ternary CuO, Cu2O, and Cu composites, enhancing the metal-support interaction and facilitating the formation of balanced Cu0 and Cu+ dual sites as well as high active surface area after reduction. Contributed to the synergetic effect of balanced Cu+ and Cu0 species proved by density functional theory calculation and the electron-rich CNTs surface, the 40Cu/CNTs catalyst achieved strengthened catalytic performance with methanol yield of 83%, ethylene glycol yield of 99% at ethylene carbonate conversion of >99%, and 150 h of long-term running stability. Consequently, CNTs supported Cu serve as efficient non-silica based catalyst for ester hydrogenation.

The combined effects of copper and zinc on Arabidopsis involve differential regulation of chlorophyll synthesis and photosystem function.

Copper (Cu) and zinc (Zn) are both oxidation-reducing metal elements that are necessary for plant growth, and their effect often depends on their concentration. However, there are few studies that have investigated how plants are stressed and affected when the two ions are present simultaneously, especially when one ion is beneficial due to a low concentration and the other is detrimental due to a high concentration. To address this question, we treated Arabidopsis plants with either high or/and low concentrations of the two ions and investigated their mutual effects and the underlying molecular mechanism, focusing on photosynthetic function. The results showed that the photosynthetic pigment content and the performance of photosynthetic systems were most affected when both metal ions were present at detrimental concentrations (60 µM Cu for Cu60 and 350 µM Zn for Zn350). These include the effective openness of the photoreaction center, the electron transport rate and efficiency of photosystem II (PSII), the NPQ-dependent energy dissipation and the activity of photosystem I (PSI). However, when the harmful concentration of one of the two metals is combined with the beneficial concentration of the other metal (Cu5+Zn350 or Zn50+Cu60), these photosynthetic indicators are compensated to different degrees but the negative effects of copper ions at high dose are more difficult to eliminate than zinc ions. These results were also confirmed by gene expression analysis, which provides a clue to understanding the interaction between heavy metal ions, reducing metal toxicity and improving the tolerance of plants to heavy metals in practice.

Unveiling the interplay of MAPK/NF-κB/MLKL axis in brain health: Omega-3 as a promising candidates against copper neurotoxicity.

Excessive intake of copper (Cu) may lead to increased inflammatory responses in brain, which can cause damage to neurons and glial cells, thereby affecting normal brain function. Omega-3 (ω-3) is a common dietary supplement, particularly rich in DHA in the brain, known for its anti-inflammatory properties and its role in lipid balance regulation and structural maintenance. Here, ω-3 is supplemented to Cu-exposed chickens to assess its neuroprotection in vivo and in vitro. Pathologically, ω-3 significantly alleviated structural and functional abnormalities in brain under excess Cu, including barrier disruption, neuronal shrinkage necroptosis and increased release of inflammatory factors such as IL-1ß. The molecular docking analyses unveiled high enrichment values of inflammation and MAPK pathway, with IL-1ß gene enrichment the highest value. Mechanistically, DHA stabilized the active site of IL-1ß, thereby reducing the activation of NF-κB signal and phosphorylation of MAPK/MLKL cascades, ultimately mitigating Cu-induced inflammatory effects. These mechanisms elucidate the action mode of Cu neurotoxicity from aspect of MAPK/NF-κB/MLKL axis and the promising neuroprotection of ω-3.

Structural Snapshots, Trajectory and Thermodynamics of the Reversible µ-1,2-Peroxo/µ-1,1-Hydroperoxo Dicopper(II) Interconversion.

Hydrogen bonds involving the oxygen atoms of intermediates that result from copper-mediated O2 activation play a key role for controlling the reactivity of Cux/O2 active sites in metalloenzymes and synthetic model complexes. However, structural insight into H-bonding in such transient species as well as thermodynamic information about proton transfer to or from the O2-derived ligands is scarce. Here we present a detailed study of the reversible interconversion of a µ1,2-peroxodicopper(II) complex ([1]+) and its µ1,1-hydroperoxo congener ([2]+) via (de)protonation, including the isolation and structural characterization of several H-bond donor (HBD) adducts of [1]+ and the determination of binding constants. For one of these adducts a temperature-dependent µ1,2-peroxo/µ1,1-hydroperoxo equilibrium associated with reversible H+-translocation is observed, its thermodynamics investigated experimentally and computationally, and effects of H-bonding on spectroscopic parameters of the CuII2(µ1,2-O2) species are revealed. DFT calculations allowed to fully map and correlate the trajectories of H+-transfer and µ1,2-peroxo→µ1,1-peroxo rearrangement. These findings enhance our understanding of two key intermediates in bioinspired Cu2/O2 chemistry.

Estimation of the Salivary Copper Levels in Oral Submucous Fibrosis Condition: An In Vivo Study.

AIM: The aim of the present study was to estimate the salivary copper levels in oral submucous fibrosis (OSMF) condition. MATERIALS AND METHODS: A total of 60 individuals of which an equal number of 30 each in normal healthy control group as well as in clinically and histopathologically (the biopsy was done once after the clinical confirmation of OSMF in the patient) confirmed patients of OSMF were included in the study group. Total of 51 males and 9 females were considered for the present study and the age distribution of these groups ranged from a minimum of 21 years to a maximum of 74 years. Unstimulated whole saliva was collected from the patient followed by the conventional biopsy practice. The collected saliva was then subjected for the analysis of copper levels. Trace element copper was estimated by using Digital Semiautomatic Analyzer with the help of copper kit. The clinical mouth opening of OSMF was estimated. Analysis of variance (ANOVA) and Tukey HSD post hoc test was used analyze the data wherein the participants were grouped into age ranges of 20-30, 31-40, 41-50, and >60 years. RESULTS: The mean salivary copper level among OSMF and control groups with respect to age in 20-30 years was 55.98 ± 15.50 and 30.87 ± 7.70, in 31-40 years was 63.96 ± 21.13 and 32.95 ± 4.56, in 41-50 years was 50.11 ± 6.83 and 30.46 ± 3.28, and >60 years was 45.65 and 13.67 µg/dL, respectively. The mean salivary copper levels among OSMF and Control groups with respect to males were 55.60 ± 15.27 and 31.18 ± 6.97 and among females were 67.0 ± 24.25 and 30.06 ± 5.77 µg/dL, respectively. The mean salivary copper levels with histopathological grades in very early stage was 47.18 ± 5.73, in early stage was 49.22 ± 7.65, in moderately advanced was 73.53 ± 10.62 and in OSMF with mild dysplasia was 79.98 ± 16.27 µg/dL, respectively. The mean salivary copper levels in individuals with clinical mouth opening more than 35 mm was 45.65 ± 6.57, in 25-35 mm was 48.94 ± 21.60, in 15-25 mm was 70.54 ± 3.52 and in less than 15 mm was 81.50 ± 16.66, respectively. CONCLUSION: The present study concluded that salivary trace element levels could be used as potential diagnostic and prognostic markers in patients with OSMF. CLINICAL SIGNIFICANCE: Trace elements are involved in many different physiological and metabolic processes in humans, either directly or indirectly. Copper is involved in vital biochemical activities like different redox and free radical formation and in maintaining cellular proton homeostasis. It is also associated with the processing of oxygen and a component of arecanut in all forms, which is implicated in the etiology of OSMF. How to cite this article: Gupta R, Jayanti I, Das A, et al. Estimation of the Salivary Copper Levels in Oral Submucous Fibrosis Condition: An In Vivo Study. J Contemp Dent Pract 2024;25(5):498-502.

Effect of primary copper metabolism disturbance on elemental, protein, and lipid composition of the organs in Jackson toxic milk mouse.

Toxic milk (txJ) is an autosomal recessive mutation in the Atp7b gene in the C3H/HeJ strain, observed at The Jackson Laboratory in Maine, USA. TxJ mice exhibit symptoms similar to those of human Wilson's disease (WD). The study aimed to verify organ involvement in a mouse model of WD. TxJ mice and control animals were sacrificed at 2, 4, 8, and 14 months of age. Total X-ray Fluorescence Spectroscopy (TXRF) was used to determine the elemental concentration in organs. Tissue chemical composition was measured by Fourier Transform Infrared Spectroscopy (FTIR). Additionally, hybrid mapping of FTIR and microXRF was performed. Elevated concentrations of Cu were observed in the liver, striatum, eye, heart, and duodenum of txJ mice across age groups. In the striatum of the oldest txJ mice, there was lower lipid content and a higher fraction of saturated fats. The secondary structure of striatum proteins was disturbed in txJ mice. In the livers of txJ mice, higher concentrations of saturated fats and disturbances in the secondary structure of proteins were observed. The concentration of neurofilaments was significantly higher in txJ serum. The distribution of Cu deposits in brains was uniform with no prevalence in any anatomic structure in either group, but significant protein structure changes were observed exclusively in the striatum of txJ. In this txJ animal model of WD, pathologic copper accumulation occurs in the duodenum, heart, and eye tissues. Increased copper concentration in the liver and brain results in increased saturated fat content and disturbances in secondary protein structure, leading to hepatic injury and neurodegeneration.

Deciphering electrocatalytic hydrogen production in water through a bioinspired water-stable copper(II) complex adorned with (N2S2)-donor sites.

Electrocatalytic hydrogen production stands as a pivotal cornerstone in ushering the revolutionary era of the hydrogen economy. With a keen focus on emulating the significance of hydrogenase-like active sites in sustainable H2 generation, a meticulously designed and water-stable copper(II) complex, [Cl-Cu-LN2S2]ClO4, featuring the N,S-type ligand, LN2S2 (2,2'-((butane-2,3-diylbis(sulfanediyl))bis(methylene))dipyridine), has been crafted and assessed for its prowess in electrocatalytic H2 production in water, leveraging acetic acid as a proton source. The molecular catalyst, adopting a square pyramidal coordination geometry, undergoes -Cl substitution by H2O during electrochemical conditions yielding [H2O-Cu-LN2S2]2+ as the true catalyst, showcases outstanding activity in electrochemical proton reduction in acidic water, achieving an impressive rate of 241.75 s-1 for hydrogen generation. Controlled potential electrolysis at -1.2 V vs. Ag/AgCl for 1.6 h reveals a high turnover number of 73.06 with a commendable Faradic efficiency of 94.2%. A comprehensive analysis encompassing electrochemical, spectroscopic, and analytical methods reveals an insignificant degradation of the molecular catalyst. However, the post-CPE electrocatalyst, present in the solution domain, signifies the coveted stability and effective activity under the specified electrochemical conditions. The synergy of electrochemical, spectroscopic, and computational studies endorses the proton-electron coupling mediated catalytic pathways, affirming the viability of sustainable hydrogen production.

Novel multitarget analgesic candidate SZV-1287 demonstrates potential disease-modifying effects in the monoiodoacetate-induced osteoarthritis mouse model.

Introduction: Monoiodoacetate (MIA)-induced osteoarthritis (OA) is the most commonly used rodent model for testing anti-OA drug candidates. Herein, we investigated the effects of our patented multitarget drug candidate SZV-1287 (3-(4,5-diphenyl-1,3-oxazol-2-yl) propanal oxime) that is currently under clinical development for neuropathic pain and characterized the mouse model through complex functional, in vivo imaging, and morphological techniques. Methods: Knee OA was induced by intraarticular MIA injection (0.5 and 0.8 mg). Spontaneous pain was assessed based on weight distribution, referred pain by paw mechanonociception (esthesiometry), edema by caliper, neutrophil myeloperoxidase activity by luminescence, matrix metalloproteinase activity, vascular leakage and bone remodeling by fluorescence imaging, bone morphology by micro-CT, histopathological alterations by semiquantitative scoring, and glia activation by immunohistochemistry. Then, SZV-1287 (20 mg/kg/day) or its vehicle was injected intraperitoneally over a 21-day period. Results: MIA induced remarkably decreased thresholds of weight bearing and paw withdrawal, alterations in the tibial and femoral structures (reactive sclerosis, increased trabeculation, and cortical erosions), histopathological damage (disorganized cartilage structure, hypocellularity, decreased matrix staining and tidemark integrity, and increased synovial hyperplasia and osteophyte formation), and changes in the astrocyte and microglia density in the lumbar spinal cord. There were no major differences between the two MIA doses in most outcome measures. SZV-1287 inhibited MIA-induced weight bearing reduction, hyperalgesia, edema, myeloperoxidase activity, histopathological damage, and astrocyte and microglia density. Conclusion: SZV-1287 may have disease-modifying potential through analgesic, anti-inflammatory, and chondroprotective effects. The MIA mouse model is valuable for investigating OA-related mechanisms and testing compounds in mice at an optimal dose of 0.5 mg.

Synthesis of magnetic chitosan-composite biochar and its removal of copper ions (Cu2+) and methylene blue (MB) dye from aqueous solutions.

This study presents the synthesis and evaluation of a magnetic chitosan-modified biochar (M-BC-CS) composite, developed from waste maize straw, for the efficient removal of copper ions (Cu2+) and methylene blue (MB) dye from aqueous solutions. The composite was characterized using advanced techniques such as SEM, BET, FTIR, XPS, and XRD, confirming its enhanced surface area, porosity, and magnetic properties. The study is aimed at investigating the optimal conditions for adsorption of Cu2+ and MB by M-BC-CS through analysis of the influence of diverse adsorbent dosages, pH levels, reaction times, and initial solution concentrations. The findings demonstrated that the equilibrium duration for the adsorption of Cu2+ and MB by M-BC-CS was 60 min, resulting in corresponding equilibrium adsorption quantities of 54.42 mg/g and 67.23 mg/g, respectively. To elucidate the adsorption mechanism, the present investigation applied the pseudo-second-order kinetic model and the Langmuir isotherm. The outcomes suggested that the adsorption process is attributable to single molecular layer chemisorption. XPS and FTIR analysis determined that ion exchange and electrostatic interactions are the predominant mechanisms responsible for the simultaneous adsorption of Cu2+ and MB, and a competitive relationship exists between these mechanisms. In addition, M-BC-CS exhibited exceptional magnetic separation performance, enabling effortless and effective separation when exposed to an external magnetic field. Furthermore, the results demonstrated that M-BC-CS has good reusability and high adsorption capacity also in real wastewater, thus emphasizing its potential as a promising adsorbent for the elimination of Cu2+ and MB from aqueous solutions.

Study on the Commercial Metalized Plastic Current Collector PET-Cu and PP-Cu Toward High-Energy Lithium-Ion Battery.

Commercial metalized plastic current collector (MPCC) is receiving widespread attention from the business and academic communities, due to its properties of excellent electrical conductivity and low mass density. However, the application of MPCC on the side of copper is rarely studied. Herein, sandwich-like polyethylene terephthalate-based (PET) and polypropylene-based (PP) copper (Cu) current collectors via magnetron sputtering and electroplating are fabricated. Most importantly, the electrical performance, mechanical safety quality, and revealed the corresponding failure mechanism for the MPCC cells are first systematically evaluated. First, during the 45 °C electrical cycling tests, PET-Cu CC (82.67%) and PP-Cu CC (82.32%) cells both have comparable capacity retention with the traditional Cu CC (Tra-Cu CC) cell (84.55%) after 500 cycles. The slight reduction in the cycling performance is induced by the crack of the Cu layer around the embedded SiO2 particle for PET-Cu CC cell and the detachment of Cu layer for PP-Cu CC cell. Second, during the nail-penetration test, MPCC cells maintain no fire and explosion for more than 5 min, since the heat-shrinkable function of polymeric film can interrupt the continuous Joule heat released by internal short-circuit. This work provides important guidance for the large-scale application of MPCC in the field of lithium-ion batteries.

A novel peptide fluorescent chemical sensor capable of detecting Cu2+, Zn2+, and S2.

A novel peptide-based chemical fluorescence sensor L (Dansyl-His-Pro-Thr-Cys-NH2) was designed and synthesized. This sensor exhibits an "On-Off-On" detection cycle to detect Cu2+, Zn2+, and S2- in solution. According to the chelation-enhanced fluorescence (CHEF) mechanism, when Zn2+ is present, the fluorescence is significantly enhanced and a blue shift occurs, representing a "Turn-On" phase of the fluorescence detection mode. Because copper ions (Cu2+) have a paramagnetic quenching sensing mechanism, the fluorescence of L quenches rapidly with the formation of the L-Cu system, representing the "Turn-Off" phase. The subsequent introduction of S2- to the L-Cu system results in the recovery of the L-fluorescence, thereby representing the second "Turn-On" phase. As a peptide molecule, the sensor L has several advantages over other types of sensors, including water solubility, high sensitivity, and good biocompatibility, with a very low detection limit. The detection lines of Zn2+ and Cu2+ are 97 nM (R = 0.993) and 75 nM (R = 0.995), respectively. Additionally, the sensor does not exhibit any obvious cell toxicity. These results indicate that this peptide chemiluminescent sensor has the potential to be applied in in vivo detection.