Search Results (492)

Chelating agents can extend the operational pH range of iron-based advanced oxidation processes, yet comprehensive studies on chelated Fe-activated persulfate systems for textile dye degradation remain scarce. This study establishes an integrated framework for optimizing Fe(II)/persulfate (PS) systems using chelating ligands and hybrid energy inputs under near-neutral conditions. Among the tested systems, Fe(II)/PS complexed with citric acid (CA) exhibited superior performance, achieving ~91% dye removal within 20 min at pH 6.5 under optimized conditions (1.25 mM Fe(II), 10 mM PS, 0.1 mM CA). Chelation stabilized Fe redox cycling and prevented precipitation, enabling effective catalysis across pH 3–10. Optimal CA/Fe and Fe/PS ratios (0.1:1.25 and 1.25:10) yielded ~96% decolorization and 67.65% TOC removal in 60 min, while excessive chelation reduced activity. Transition metal screening (Mn(II), Zn(II), Cu(II), Co(II), and Ni(II) confirmed Fe(II) as the most effective activator, providing removal efficiencies up to 3.2-fold higher than competing metals. Mixed-dye experiments showed competitive degradation, with >37% color removal after 60 min for ternary dye mixtures. Mineralization reached ~92% TOC reduction after 120 min, indicating deep oxidation beyond chromophore cleavage. Reactive species quenching revealed a mixed oxidation mechanism involving ^•OH radicals and high-valent Fe(IV) species. Hybrid assistance improved mineralization, with UVC increasing TOC removal by 15.6%, while solar irradiation provided moderate enhancement under low-energy input. In contrast, low-power ultrasound (40 kHz, 60 W) delivered only 17.6 W acoustic power to the solution and did not improve performance due to limited cavitation and mixing. This work thus contributes a robust platform for advancing chelated iron-persulfate oxidation systems toward practical, effective treatment of recalcitrant dye-contaminated wastewaters under near-neutral conditions. Full article

One-dimensional hybrid organic–inorganic semiconductors enable band-edge engineering through reduced dimensionality and interfacial orbital hybridization. Nevertheless, the electronic physics of Cu/Ag-based systems has received limited attention. Here, we perform high-throughput first-principles calculations on 90 Cu/Ag halide HOISs derived from experimentally reported parent structures to elucidate bonding-dependent electronic behavior. We uncover a clear transition from electronically isolated inorganic chains in ionic hybrids to strongly hybridized band edges in covalent and mixed-bonding hybrid frameworks, where ligand p orbitals cooperatively couple with Cu-derived states and halogen p orbitals. This hybridization produces p-orbital-dominated band edges, enhanced dispersion, and light-hole effective masses along the 1D chains. Guided by this bonding-driven mechanism, we further identify four Cu-based compounds, which are helpful for tuning light-harvesting properties in low-dimensional hybrid semiconductors. Full article

The reaction mechanism of the gold-catalyzed hydrothiolation of alkenes (1) with thiols (2) has been investigated in detail. The tetranuclear gold complex, (PPh₃)₄Au₄(SPh)₂(NTf)₂ (A), is a key intermediate in the catalytic hydrothiolation of alkenes. It forms instantaneously when PPh₃AuNTf₂ and PhSH are mixed in THF. Monitoring the reaction over time using ³¹P NMR spectroscopy revealed that gold complex A remained stable in the reaction system throughout the hydrothiolation process. In addition, we successfully observed a rapid ligand-exchange reaction between the thiolate group of gold complex A and thiols in solution. The gold-catalyzed alkene hydrothiolation reaction has been applied to the catalytic hydrothiolation of allenes, which have degenerate double bonds. Hydrothiolation of allenes proceeded regioselectively at the terminal double bond. However, the yield was lower than that observed for alkenes, and catalyst deactivation occurred. The hydrothiolation products of allenes were difficult to detach from the gold catalyst, necessitating an increase in the reaction temperature. Since high periodic transition metals such as gold and platinum are effective for hydrothiolation of alkenes and allenes, it is interesting to clarify whether iridium complexes, which belong to the same period as gold and platinum, could also catalyze alkene hydrothiolation. Through a detailed investigation of iridium ligands and reaction conditions, it was found that, in iridium systems, disulfide formation via oxidative coupling of thiols occurs preferentially over hydrothiolation reactions. This is likely due to steric hindrance around the iridium center, which inhibits alkene coordination to the iridium. Additionally, the hydrothiolation proceeding at low yields is believed to be a radical reaction involving electron transfer through the iridium complex. Full article

Thiosulfate leaching is considered a promising alternative to cyanidation for gold extraction because it can be achieved at a low cost. However, existing leaching systems struggle to balance leaching efficiency with thiosulfate consumption. Herein, a novel synergistic Cu-CH₃NH₂-NH₃ leaching system was proposed, balancing thiosulfate consumption and gold leaching efficiency through a mixed-ligand strategy. Thermodynamic analysis revealed that the steric hindrance and electron-donating effects of methylamine effectively block the oxidative decomposition pathway of thiosulfate by Cu(II), significantly reducing thiosulfate consumption. However, this also reduced the dissolution rate of gold. By introducing ammonia to adjust the Cu(II) coordination environment, the system achieved a gold leaching rate of 88.6% with a thiosulfate consumption of 14.2 kg/t-ore, significantly outperforming the traditional Cu-NH₃ system. In this system, the gold leaching process mainly is catalyzed by the mixed-ligand complex Cu(NH₃)_x(CH₃NH₂)_4−x²⁺. Within the coordination sphere, the methyl group of CH₃NH₂ inhibits the axial attack of S₂O₃²⁻ on Cu(II) via electron-donating and steric hindrance effects, thereby blocking the redox pathway of S₂O₃²⁻; simultaneously, NH₃ provides active sites to promote the gold oxidation. This study provides a vital theoretical basis and technical support for developing green, low-cost, and high-efficiency gold leaching processes. Full article

Background: There is currently increasing interest in atypical opioid compounds capable of expanding their clinical applications beyond pain management, including the treatment of psychiatric disorders and substance abuse. In this context, the cyclotetrapeptide c[Trp-Phe-D-Pro-Phe] (CJ-15,208, 1) and its derivatives represent an unusual class of opioid peptides. This compound was found to be a mixed KOR/MOR antagonist in vitro, but it acted as an agonist in vivo. For its diverse analogues, it appeared that receptors’ affinity, selectivity, and agonist/antagonist activity greatly varied upon modifications to backbone geometry and the 3D display of pharmacophores. Methods: We utilized NMR, molecular dynamics, and molecular docking to analyze 3D structures and pharmacodynamic properties of selected representative cyclopeptide analogues of 1. Results: The simulations support that, despite its contradictory functional activity in vitro and in vivo, 1 can bind to the active conformation of receptors in an agonist-like fashion. In general, Trp appeared to be the fundamental pharmacophore in the ligand–receptor complexes. In particular, agonists showed a direct interaction between the indole ring and the carboxylate of the conserved Asp(3:32). Conclusions: These studies support a distinctive pharmacodynamic model for this class of compounds, potentially useful for the design of opioid compounds with novel binding/activity profiles and improved therapeutic effects. Full article

Background/Objectives: The use of the drug delivery system is notable for the systemic improvement of low orally bioavailable compounds, such as the bioactive phenolic acid, syringic acid. Innovative techniques are employed to enhance the performance of certain drug delivery systems. In connection with our previously reported journal with the use of MIL-100(Fe) as a drug carrier for syringic acid, this study utilized a mixed-linker synthesis of syringic acid and trimesic acid and characterized the properties in comparison with the unmodified MIL-100(Fe) through a solid solution approach. Methods: Modified MIL-100(Fe) was synthesized by substituting different molar concentrations of syringic acid for trimesic acid through de novo synthesis. Simple impregnation of syringic acid was carried out at 12, 24, 36, and 48 h and at 1:1 and 1:2 molar ratios of MIL-100(Fe) to syringic acid. Characterization was performed via PXRD, FTIR, BET, SEM, and DLS. In vivo studies included acute oral toxicity testing (OECD 425) and bioavailability assessment in Sprague Dawley rats. Results: The optimized amount of syringic acid to be substituted for trimesic acid is 0.10 mmol, as confirmed by the value of the PXRD. Optimized drug loading of 66.85 ± 0.004% was achieved using a 1:2 ratio of syringic acid to MIL-100(Fe)-10% over 36 h. Structural modifications were confirmed via FTIR, specifically through shifts at 1239.2 cm⁻¹, while TGA demonstrated thermal stability up to approximately 350 °C. Morphological analysis by SEM showed octahedral particles (210.70 ± 1.23 nm), and a decrease in BET surface area post-loading verified successful encapsulation. While in vitro release was media-dependent, toxicity studies at 2000 mg/kg showed no adverse effects; notably, SGOT and SGPT levels decreased, though BUN and creatinine levels rose. Compared to pure oral syringic acid, the SYA@MIL-100(Fe)-10% formulation demonstrated a 5.09-fold increase in relative bioavailability. Furthermore, it outperformed intraperitoneal administration of the drug by 1.65-fold. Conclusions: Modification of MIL-100(Fe) by incorporating syringic acid into the framework as a substituted organic linker indicates that SYA@MIL-100(Fe)-10% is a safe and effective delivery system for syringic acid, enhancing oral bioavailability. To the best of our knowledge, this is the first study to investigate the mixed-linker synthesis of MIL-100(Fe) by utilizing syringic acid as a structural co-ligand, rather than solely as an encapsulated guest. While MIL-100(Fe) has been extensively employed as a carrier for various therapeutics, this research uniquely integrates the active agent into the framework lattice itself to modulate porosity and loading capacity, subsequently evaluating its systemic performance in an in vivo model. Full article

Developing molecular electrocatalysts with controllable and predictable properties remains a central challenge in hydrogen evolution reaction (HER) catalysis. Herein, four Sb(III) corrole complexes (1–4) bearing zero to three p-cyano-substituted meso-phenyl groups (-CN Ph) were synthesized to investigate the effect of electron-withdrawing substituents on their catalytic HER performance, in which complexes 2–4 are newly reported. All prepared complexes were well characterized via UV–vis, NMR, HRMS, and XPS. SEM–EDS and UV–vis analyses indicated their uniform dispersion and excellent stability under organic and neutral aqueous solvent electrolysis conditions. When using TsOH as the proton source in DMF, complex 4 exhibited the highest activity with a TOF of 42.19 s⁻¹ at an overpotential of 895 mV. In mixed aqueous–organic media, the Faradaic efficiency of complex 4 reached 85.5%. The HER activity increases with the increasing number of cyano groups, and this observation has been rationalized via DFT calculations, which indicates a ligand-centered reduction and supports a possible ECEC pathway for the HER. These results highlight that cyano functionalization can modulate the electronic properties of Sb(III) corroles, thereby enhancing HER performance. This is helpful for designing efficient Sb(III) corrole-based HER catalysts. Full article

Perovskite quantum dots (PeQDs) are highly promising luminescent materials for next-generation displays owing to their excellent optoelectronic properties, such as narrow emission linewidth, high photoluminescence quantum yield, tunable bandgap, and solution processability. Blue-emitting PeQDs are particularly crucial for realizing full-color displays with high color purity. This review systematically summarizes synthesis strategies for blue-emitting PeQDs and their recent advances in perovskite light-emitting diodes (PeLEDs). We first introduce the working principles of PeLEDs and detail three primary approaches to achieving blue emission through mixed-halide engineering, quasi-two-dimensional structure construction via A-site cation substitution, and quantum size effect utilization. We then review mainstream synthesis methods, including hot-injection, ligand-assisted reprecipitation, and post-synthetic anion exchange, discussing their respective advantages and limitations. Key device optimization strategies are also outlined, covering surface passivation, core–shell structures, interface engineering, and light outcoupling enhancement. Finally, we address current challenges in material stability, efficiency roll-off, and charge imbalance and provide an overview of future research directions for high-performance blue PeLEDs based on PeQDs. Full article

High Mobility Group Box 1 (HMGB1) and S100 proteins are major ligands of Receptor for Advanced Glycation End-products (RAGE) and have causal roles in endometriosis lesions. Yet the AGE–RAGE pathway that unifies Advanced Glycation End-products (AGEs) with these ligands has not been assessed in endometriosis. In diabetes, atherosclerosis, and chronic kidney disease, AGE–RAGE links insulin resistance and oxidative stress to inflammation, fibrosis, and organ harm. Endometriosis shares key drivers of AGE accumulation, including insulin resistance, oxidative stress, and chronic inflammation. Endometriosis is also linked to higher vascular risk and arterial stiffness. We asked whether AGE–RAGE could bridge metabolic stress to pelvic lesions and systemic risk. We did a focused review of mechanisms and an evidence map of studies on AGEs, RAGE, or known RAGE ligands in endometriosis. We grouped findings as most consistent with a driver, amplifier, consequence, or parallel role. We included 29 studies across human samples, cell systems, and animal models. Few studies measured AGE adducts directly. Most work tracked RAGE ligands (mainly HMGB1 and S100 proteins) and downstream immune and angiogenic programs. Across models, this pattern fits best with a self-reinforcing loop after lesions form. RAGE expression often aligned with lesion remodeling, especially fibrosis. Blood and skin readouts of AGE burden were mixed and varied by cohort and sample type. A central gap is receptor proof. Many models point to shared Toll-like receptor 4 (TLR4)/ nuclear factor kappa B (NF-κB) signaling, but few test RAGE dependence. Overall, current evidence supports AGE–RAGE as a disease-amplifying loop involved in chronic inflammation and fibrosis rather than an initiating trigger. Its effects likely vary by stage and site. Priorities now include direct lesion AGE measurement, paired systemic–pelvic sampling over time, receptor-level studies, and trials testing diet or drug interventions against clear endpoints. Outcomes could include fibrosis, angiogenesis, immune state, pain, and oocyte and follicle function. Full article

Background/Objectives: Spondylocostal dysostosis (SCDO) is a rare disorder characterized by congenital malformations of the spine and ribs. SCDO affects 1 in 40,000 human births, with rare cases also reported in dogs. Mutations in DLL3, encoding a critical Notch signaling pathway ligand, account for a majority of human SCDO cases. The remaining cases have variants in HES7, LFNG, MESP2, RIPPLY2, TBX6, and DLL1, which code for proteins in the Notch pathway. A mixed-breed litter of three dogs presented with varying degrees of spinal malformations and underwent comprehensive phenotyping including radiographic and neurologic examination. Two littermates demonstrated classic SCDO features including shortened torsos, vertebral malformations, and rib abnormalities, while a third showed only caudal vertebral truncation. Methods: Short-read whole-genome sequencing was performed on all three animals, followed by variant filtering and analysis using the two severely affected dogs as cases and 173 control dogs of various breeds. Variants were prioritized based on segregation patterns, population frequency, and predicted functional impact using established bioinformatics tools. Results: Variant analysis identified a novel splice acceptor variant in DLL3 (c.650-2A>C). This mutation, located at the splice acceptor site preceding exon 5, is predicted to disrupt critical EGF-like domains and O-fucosylation sites essential for DLL3 protein function. Conclusions: This study identifies a DLL3 splice variant causing SCDO in dogs, demonstrating phenotypic conservation with humans. These findings refine our understanding of genotype–phenotype correlations and demonstrate the value of comparative genomics for rare developmental disorders. Full article

Seawater electrolysis offers a promising route for sustainable hydrogen production in coastal areas, leveraging solar energy while reducing freshwater consumption. Yet, chloride-induced corrosion severely limits conventional electrodes such as titanium, which depend on passive titanium dioxide films and display minimal hydrogen evolution reaction activity (|i₀,H₂| ≈ 0.001–0.01 A/m²). Here, we report for the first time the use of copper-based coordination compounds—a triazole-derived polymer (CC_Cu) and a Prussian Blue Analogue (CuHCF)—as dual-function electrodes combining corrosion resistance with electrocatalytic activity. Structural integrity was verified by FTIR, TGA, XRD, and SEM/EDS analyses. Electrochemical tests in 0.5 M NaCl, interpreted using mixed potential theory, revealed corrosion potentials (E_corr) of −40 mV versus Standard Hydrogen Electrode (CuHCF) and −23 mV versus Standard Hydrogen Electrode (CC_Cu), and corrosion current densities of 0.259 and 0.379 A/m², respectively. Both exhibited hydrogen evolution reaction exchange current densities significantly higher than titanium (0.019 A/m² for CuHCF and 0.062 A/m² for CC_Cu). CuHCF achieved a Tafel slope of 222 mV/dec, comparable to NiMoP alloys and carbon steel. Complementary density functional theory calculations elucidated how metal–ligand interactions and electronic redistribution govern both catalytic performance and degradation. These findings introduce a new concept of semi-electrocatalysts, where copper coordination compounds act as structurally adaptive, low-cost materials bridging corrosion resistance and hydrogen evolution in seawater systems. Full article

The “Neuroimaging and Pathology Biomarkers in Parkinson’s Disease” course held on 12–13 September 2025 in Milan, Italy, convened an international faculty to review state-of-the-art biomarkers spanning neurotransmitter dysfunction, protein pathology and clinical translation. Here, we synthesize the four themed sessions and highlights convergent messages for diagnosis, stratification and trial design. The first session focused on neuroimaging markers of neurotransmitter dysfunction, highlighting how positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetic resonance imaging (MRI) provided complementary insights into dopaminergic, noradrenergic, cholinergic and serotonergic dysfunction. The second session addressed in vivo imaging of protein pathology, presenting recent advances in PET ligands targeting α-synuclein, progress in four-repeat tau imaging for progressive supranuclear palsy and corticobasal syndromes, and the prognostic relevance of amyloid imaging in the context of mixed pathologies. Imaging of neuroinflammation captures inflammatory processes in vivo and helps study pathophysiological effects. The third session bridged pathology and disease mechanisms, covering the biology of α-synuclein and emerging therapeutic strategies, the clinical potential of seed amplification assays and skin biopsy, the impact of co-pathologies on disease expression, and the “brain-first” versus “body-first” model of pathological spread. Finally, the fourth session addressed disease progression and clinical translation, focusing on imaging predictors of phenoconversion from prodromal to clinically overt stages of synucleinopathies, concepts of neural reserve and compensation, imaging correlates of cognitive impairment, and MRI approaches for atypical parkinsonism. Biomarker-informed pharmacological, infusion-based, and surgical strategies, including network-guided and adaptive deep brain stimulation, were discussed as examples of how multimodal biomarkers may inform personalized management. Across all sessions, the need for harmonization, longitudinal validation, and pathology-confirmed outcome measures was consistently emphasized as essential for advancing biomarker qualification in multicentre research and clinical practice. Full article

Background/objectives: Cannabidiol (CBD) is a non-psychoactive constituent of Cannabis sativa, which has potential skeletal benefits through modulation of bone cell function and inflammatory signalling. However, evidence of its effects and mechanisms in bone health remains fragmented. This scoping review summarised the current findings on the impact of CBD on bone outcomes and its mechanisms of action. Methods: A systematic search of PubMed, Scopus, and Web of Science was conducted in October 2025 for original studies published in English, with the primary objective of examining the effects of CBD on bone health, regardless of study design. After applying inclusion and exclusion criteria, 24 primary studies were included. Data on model design, CBD formulation, treatment parameters, bone-related outcomes, and proposed mechanisms were extracted and analysed descriptively. Results: Among the studies included, eleven demonstrated beneficial effects of CBD on bone formation, mineralisation, callus quality, or strength; eleven showed mixed outcomes; and two demonstrated no apparent benefit. Previous studies have shown that CBD suppresses bone resorption by reducing osteoclast differentiation and activity while promoting osteoblast proliferation and matrix deposition. Mechanistically, CBD’s effects involve activation of cannabinoid receptor 2, modulation of the receptor activator of nuclear factor-κB ligand/osteoprotegerin pathway, and regulation of osteoblastogenic and osteoclastogenic signalling through bone morphogenetic protein, Wnt, mitogen-activated protein kinase, nuclear factor-κB, and peroxisome proliferator-activated receptor signalling. The anti-inflammatory and antioxidant actions of CBD further contribute to a favourable bone microenvironment. Conclusions: Preclinical evidence suggests that CBD has a bone-protective role through multifaceted pathways that enhance osteoblast function and suppress osteoclast activity. Nevertheless, robust human trials are necessary to confirm its efficacy, determine its optimal dosing, and clarify its long-term safety. Full article

The increasing demand for rapid identification of bacteria capable of degrading environmentally relevant organic compounds highlights the need for scalable and selective analytical tools. Cupriavidus necator catabolizes several hydroxybenzoic acids, including 2-hydroxybenzoate (salicylate, 2-HBA), 4-hydroxybenzoate (4-HBA), and 3-hydroxybenzoate (3-HBA), funneling them into central aromatic catabolism via monooxygenation to 2,5-dihydroxybenzoate (gentisate, 2,5-dHBA) and 3,4-dihydroxybenzoate (protocatechuate, 3,4-dHBA) followed by the oxidative cleavage reaction, enabling complete conversion to tricarboxylic acid (TCA) cycle intermediates. To quantify how readily C. necator is able to activate catabolic genes in response to hydroxybenzoic acid, an extracellular ligand, we applied an approach centered on a transcription-factor (TF)-based biosensor that combines ligand-bound regulator activity with a fluorescent reporter. This approach allowed to evaluate the ligand sensitivity by determining gene activation threshold AC_min and half-maximal effective concentration EC₅₀. Amongst studied hydroxybenzoic acids, 2-HBA and 4-HBA sensors from C. necator showed very low thresholds 4.8 and 2.4 μM and EC₅₀ values of 19.91 and 13.06 μM, indicating high sensitivity to these compounds and implicating a scavenging characteristic of associated catabolism. This study shows that the TF-based-biosensor approach applied for mapping functional sensing ranges of hydroxybenzoates combined with the research and informatics of catabolism can advance our understanding of how gene expression regulation systems have evolved to respond differentially to the availability and concentration of carbon sources. Furthermore, it can inform metabolic engineering strategies in the prevention of premature pathway activation or in predicting competitive substrate hierarchies in complex mixed environments. Full article

This paper presents accurate TD-DFT calculations for several mixed-ligand gold(III) complexes with ligands including Cl⁻, Br⁻, I⁻, OH⁻, and NH₃. The calculated results show excellent agreement with available experimental data. The spectral shapes are determined by charge transfer transitions, which are systematically influenced by the ligand’s position in the spectrochemical series. The main vertical electron transitions and the molecular orbitals involved are identified and discussed. Furthermore, the results indicate that the iodide-containing gold(III) complexes, [AuCl₂I₂]⁻ and [AuI(OH)₃]⁻, are viable candidates for practical synthesis. Full article