Search Results (476)

Background/Objectives: Capsanthin is a xanthophyll carotenoid from Capsicum species with an extended conjugated polyene chain that underlies both its orange–red color and strong antioxidant potential. In this study, we investigated whether capsanthin protects RA-differentiated SH-SY5Y neuron-like cells against glutamate-induced stress. Methods: Neuronal dysfunction was induced by glutamate exposure, and capsanthin treatment was evaluated using cell viability, reactive oxygen species (ROS) production, antioxidant defense markers, inflammatory cytokines, mitochondrial energy status, and apoptosis-related endpoints. Antioxidant responses were assessed using superoxide dismutase, catalase, glutathione peroxidase activities, and total antioxidant capacity. Cytokine release (TNFα, IL-6, IL-8, IL-4, IL-10) was quantified by ELISA. Mitochondrial function was monitored using ATP content. Apoptosis-associated genes (BAX, BCL-2, CASP3, and CASP9) were analyzed using SYBR Green-based RT-qPCR, complemented by caspase-9 ELISA and caspase-3 Western blotting. Results: Glutamate increased oxidative stress and shifted the cytokine profile toward a pro-inflammatory state, accompanied by reduced ATP levels and a pro-apoptotic transcriptional pattern. Capsanthin significantly attenuated glutamate-induced ROS production, stabilized antioxidant enzyme activities and total antioxidant capacity, reduced pro-inflammatory cytokines while supporting anti-inflammatory signaling, and preserved ATP levels. Conclusions: Overall, capsanthin mitigated excitotoxic stress by maintaining redox balance, limiting inflammatory responses, and protecting mitochondrial energy metabolism in neuron-like cells, supporting its potential as a neuroprotective candidate for glutamate-induced neuronal stress. Full article

We introduce a BiHom-type skew-symmetric bracket on general linear Lie algebra $GL\left(V\right)$ built from two commuting inner automorphisms $\alpha =A{d}_{\psi }$ and $\beta =A{d}_{\varphi }$, with $\psi ,\varphi \in GL\left(V\right)$ and integers $i,j$. We prove that $(GL\left(V\right),{[·,·]}_{(\psi ,\varphi )}^{(i,j)},\alpha ,\beta )$ is a BiHom–Lie algebra, and we study the Lax equation obtained by replacing the commutator in the finite nonperiodic Toda lattice by this bracket. For the symmetric choice $\varphi =\psi$ with $(i,j)=(0,0)$, the deformed flow is equivariant under conjugation and becomes gauge-equivalent, via $\tilde{L}={\psi }^{-1}L\psi$, to a Toda-type Lax equation with a conjugated triangular projection. In particular, scalar deformations amount to a constant rescaling of time. On embedded $2\times 2$ blocks, we derive explicit trigonometric and hyperbolic formulae that make symmetry constraints (e.g., tracelessness) transparent. In the asymmetric hyperbolic case, we exhibit a trace obstruction showing that the right-hand side is generically not a commutator, which amounts to symmetry breaking of the isospectral property. We further extend the construction to the weakly coupled Toda lattice with an indefinite metric and provide explicit $2\times 2$ solutions via an inverse-scattering calculation, clarifying and correcting certain formulas in the literature. The classical Toda dynamics are recovered at special parameter values. Full article

The emergence of electrically conductive polymeric materials has revolutionized the landscape of sustainable energy technologies, presenting unprecedented opportunities for advancing both photovoltaic conversion systems and electrochemical energy-storage platforms. These remarkable macromolecular materials exhibit distinctive characteristics including adjustable electronic band structures, exceptional mechanical adaptability, solution-phase processability, and cost-effective manufacturing potential. This extensive review provides an in-depth examination of the fundamental principles governing charge carrier mobility in conjugated polymer systems, explores diverse synthetic methodologies for tailoring molecular architectures, and analyzes their transformative applications across multiple energy technology domains. In photovoltaic technologies, electrically conductive polymers have driven major advancements in organic solar cells and photoelectrochemical systems, significantly improving energy conversion efficiency while reducing manufacturing costs. In electrochemical energy storage, their integration into supercapacitors and rechargeable lithium-based batteries has enhanced charge storage capability, accelerated charge–discharge processes, and extended operational lifespan compared with conventional electrode materials. This comprehensive analysis emphasizes emerging developments in hybrid composite architectures that combine conductive polymers with carbon-based nanomaterials, metal oxides, and other functional components to create next-generation flexible, lightweight, and wearable energy systems. By synthesizing fundamental materials chemistry with device engineering perspectives, this review illuminates the transformative potential of electrically conductive polymers in establishing sustainable, efficient, and resilient energy infrastructures for future technological landscapes. Full article

Breast cancer is the most common cancer and the most important cause of cancer-related death in females worldwide. Antibody–drug conjugates (ADCs) represent a novel class of targeted therapies that combine the precision of monoclonal antibodies with the potent cell-killing activity of cytotoxic drugs. This review highlights recent mechanistic, technological, and clinical developments of ADCs in breast cancer, including next-generation ADCs beyond those that target HER2 (human epidermal growth factor receptor 2). Authors performed a systematic literature study for ADCs and their structural features, including their components (antibody, linker, and payload) and their therapeutic efficacy. A frame of preclinical research findings and clinical evidence integration of HER2-targeted therapy outcomes in HER2-positive, HER2-low, and triple-negative breast cancer (TNBC) subtypes were presented. Clinical studies of antibody–drug conjugates such as trastuzumab emtansine (T-DM1), trastuzumab deruxtecan (T-DXd), and sacituzumab govitecan have demonstrated significant improvements in progression-free survival and overall survival across diverse breast cancer patient populations. ADCs offer unique advantages in breast cancer therapy by combining the precision of targeted antibodies with the potency of chemotherapy drugs. This allows them to selectively kill cancer cells, overcome resistance, reduce toxicity to healthy tissues, and expand treatment options for difficult subtypes like HER2-low and triple-negative breast cancer. Unlike previous reviews focusing on HER2-targeted ADCs, herein we review exciting ADCs targeting HER3 HER3 (human epidermal growth factor receptor 3) and Nectin-4, as well as the implications of bispecific and immune-stimulatory ADCs in the clinic. Additionally, it features mechanism-based innovations and novel trial data that revolutionize ADC applications in the HER2-low as well as the triple-negative breast cancer subtypes. The advent of ADC is changing precision oncology in breast cancer. With a new design and indications evolving, they are an attractive avenue for bypassing resistance and reducing toxicity and ultimately improving patient outcomes in the molecular subtypes. The present review summarizes recent advancements in antibody–drug conjugates (ADCs) and emerging targeted therapeutic strategies for breast cancer. It covers mechanistic insights, linker–payload innovations, receptor-based targeting approaches, clinical trial progress, and next-generation modalities that extend beyond HER2-directed ADCs. Current challenges, safety profiles, and future opportunities in engineering more selective and effective ADC platforms are also discussed. Full article

The electrochemical capture and transformation of carbon dioxide (CO₂) (ECC) has recently emerged as a transformative alternative to conventional sorbent-based processes, enabling fully reversible operation under mild conditions and direct compatibility with renewable energy sources. This review focuses on redox-active metal–organic frameworks (MOFs) as electrosorbent materials for the electrochemical capture of CO₂. Rather than encompassing all electrochemical CO₂ capture technologies, we use molecular, polymeric, and COF-based systems as a framework to define what makes a MOF truly “redox-active” for CO₂ electrosorption and how its performance can be assessed. This includes capacitive versus faradic electrosorption mechanisms and design strategies based on the redox chemistry associated with metal nodes, π-conjugated ligands, and strongly redox-active units such as tetrathiafulvalene, viologen, and ferrocene. The way in which defects affect hybrid MOF composites was highlighted, and in situ and operando spectroscopic techniques have improved the understanding of the reaction mechanism in carbon dioxide capture and release under controlled potential. Research comparing carbonaceous materials, redox polymers, and hybrid structures has highlighted both the opportunities and limitations of MOFs, particularly in terms of energy efficiency, scalability, structural robustness, and reproducibility. From a broader perspective, redox-active MOFs occupy a unique position at the intersection of coordination chemistry, electrochemistry, and materials engineering for large-scale applications. In this review, we analyze how redox activity in MOFs—at the metal nodes, ligands, and extended structures—can be harnessed to design energy-efficient, cyclic electrochemical CO₂ capture systems. Furthermore, we propose cross-cutting metrics and design rules that enable meaningful comparisons between materials and device architecture. Full article

Breast cancer (BC) is increasingly recognized as a heterogeneous disease, with complexity that extends beyond the classical luminal A/B, HER2-enriched, and triple-negative framework. Advances in molecular and functional profiling have uncovered emerging subpopulations, including HER2-low, claudin-low, BRCA-deficient (“BRCAness”), and refined TNBC subsets, such as luminal AR (LAR) and basal-like immune variants, that extend beyond traditional taxonomies. These novel classifications provide additional resolutions, offering both prognostic insight and therapeutic opportunities. In this comprehensive review, we integrate evidence from genomic, epigenetic, proteomic, immune-related, and liquid biopsy biomarkers, underscoring how they define the biology of these subgroups and predict responses to targeted therapies, such as antibody–drug conjugates, PARP inhibitors, and immune checkpoint blockade. We further highlight the role of the tumor microenvironment (TME) and intratumoral heterogeneity in shaping these entities. Collectively, recognition of emerging subtypes as clinically actionable groups represents a paradigm shift from static receptor-based models to dynamic, biomarker-driven frameworks that refine prognosis, enable patient stratification, and support precision oncology in aggressive BC. Full article

Nanogels provide unique opportunities for stabilizing fragile enzymes through soft, hydrated polymer networks. Here, we report the development of a glutathione peroxidase (GPx)-loaded nanogel (GPxNG) engineered via a mild “grafting-to” epoxy–amine coupling strategy to enhance enzyme stability and antioxidant function. An amphiphilic copolymer composed of methacrylated 2,2,6,6-tetramethyl-4-piperidyl (PMA) and glycidyl methacrylate (GMA) was synthesized by controlled reversible addition–fragmentation chain-transfer (RAFT) polymerization using a poly(ethylene glycol) (PEG) macro-chain transfer agent (macro-CTA), yielding well-defined polymer chains with reactive epoxy groups. Covalent conjugation between polymer epoxides and GPx enzyme surface amines generated soft, PEGylated nanogels with high coupling efficiency, uniform particle sizes, and excellent colloidal stability. The engineered nanogels exhibited shear-thinning injectability, robust storage stability, and non-cytotoxic behavior in RAW 264.7 macrophages. Compared with native GPx enzyme, GPxNGs demonstrated significantly enhanced reactive oxygen species (ROS) scavenging activity, including strong inhibition of lipid peroxidation and copper-induced low-density lipoprotein (LDL) oxidation. Importantly, the nanogels preserved GPx enzyme activity after extended storage, freeze–thaw cycles, and repeated catalytic use, whereas the free enzyme rapidly lost function. This protective effect arises from the nanoscale confinement of the GPx enzyme within the flexible PEG-based network, which limits unfolding and aggregation. Overall, this work introduces a simple and biocompatible “grafting-to” nanogel platform capable of stabilizing redox-active enzymes without harsh conditions. The GPx nanogels combine high enzymatic preservation, potent antioxidant activity, and excellent handling properties, highlighting their potential as a therapeutic nanoplatform for mitigating oxidative stress-associated disorders such as atherosclerosis. Full article

Background: Recurrent and metastatic head and neck squamous cell carcinoma (R/M HNSCC) after immune checkpoint inhibitor (ICI) progression represents a major clinical challenge. Between 60 and 80% of patients develop resistance, and historical salvage regimens like cytotoxic chemotherapy or chemotherapy plus cetuximab rarely extend median overall survival (mOS) beyond one year. Scope of Review: This review examines systemic therapies evaluated specifically in the post-ICI setting, emphasizing agents advancing to Phase II and III trials. Classes include chemotherapy combinations, ICI-based approaches, small-molecule targeted combinations, bispecific antibodies, antibody-drug conjugates (ADCs), and next-generation vaccines. Results: Promising signals have emerged across multiple therapeutic modalities. Targeted combination strategies have demonstrated encouraging response rates and survival outcomes in difficult-to-treat, PD-1-resistant disease. Antibody-based platforms, including antibody-drug conjugates and bispecific antibodies, continue to show consistent clinical activity across diverse patient populations, offering disease control and prolonged survival. Novel immunotherapies and therapeutic vaccines are also generating durable responses, particularly in biologically defined subgroups, highlighting the potential of immune-based precision treatments in R/M HNSCC. Conclusions: Comparative analysis highlights distinct advantages and limitations: chemotherapy ensures rapid shrinkage but poor durability; biomarker-driven small molecules achieve strong survival gains in narrow niches; ADCs and bispecifics offer balanced efficacy in unselected patients; and vaccine platforms deliver durable benefit in defined subsets. Together, these data signal a paradigm shift toward biomarker-guided, mechanism-driven strategies as the path to closing the post-ICI therapeutic gap in R/M HNSCC. Full article

Background/Objectives: This study assessed the risk associated with third-generation cephalosporin- and fluoroquinolone-resistant Salmonella from pork consumption by integrating phenotypic resistance profiles with genetic data to characterize the risks and transmission pathways. Methods: Salmonella were isolated from raw pork meat samples (n = 793) collected from fresh markets and hypermarkets across Bangkok during 2021–2022, of which 150 were extended-spectrum β-lactamase (ESBL)-producing and 31 were fluoroquinolone-resistant isolates. Phenotypic and genotypic resistance profiles were characterized. Quantitative antimicrobial resistance risk assessment (AMR RA) was conducted using a dose–response model. Results: Salmonella spp. was detected in 42.75% of pork samples, with a higher prevalence in fresh markets (75.5%) than in hypermarket samples and with concentrations ranging from 1.3 to 180 MPN/g. Twenty-eight percent of isolates were ESBL producers, with ciprofloxacin and levofloxacin resistance observed in 5.3% and 3.0%, respectively. The bla_CTX-M55 genes were located on conjugative plasmids. Whole genome sequencing revealed both vertical and horizontal gene transfer. IncHI2/N and IncC plasmids shared conserved backbones and resistance gene architectures, indicating horizontal dissemination of resistance genes. Phylogenomics suggested possible clonal transmission among pigs, pork, and humans. AMR RA estimated 88,194 annual illness cases per 100,000 people from ESBL-producing Salmonella and 61,877 from ciprofloxacin-resistant strain, compared with 95,328 cases predicted by QMRA from Salmonella contamination. Cooking pork at ≥64 °C for 3 min eliminated the risk in all scenarios. Sensitivity analysis identified initial contamination level and cooking temperature as key determinants. Conclusions: Raw pork meat consumption represents the highest risk, which can be mitigated by thorough cooking (>64 °C, ≥3 min), while integrating genomic data enhances AMR hazard identification, source attribution, and exposure assessment. Therefore, promoting well-cooked meat consumption and safe cooking practices, alongside the use of AMR genetic data to inform targeted interventions, is recommended. Full article

Based on a realistic three-dimensional geometric model, this study numerically investigates the influence of yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBCs) on the aerothermal performance of an annular combustor by employing a conjugate heat transfer (CHT) and non-premixed reactive flow coupling approach. Considering the inner and outer liners, double-wall exhaust bends, and the full configuration of cooling holes, two cases—with and without the TBCs—were analyzed. The results reveal that the application of TBCs markedly modifies the near-wall flow structures and heat transfer characteristics. The cooling air mass flow rate decreases from 0.1211 kg/s to 0.1023 kg/s, corresponding to a 15.5% reduction in cooling load. The main recirculation zone becomes more compact, with enhanced vortex intensity, smoother velocity distribution, and improved flame stability. The high-temperature core region extends further downstream, and the peak temperature increases by approximately 80–100 K, indicating more complete combustion and greater heat retention. The outlet temperature distribution factor (OTDF) decreases from 57.34% to 44.48%, leading to a 22.4% improvement in temperature uniformity. The average wall temperatures of the inner liner, outer liner, and exhaust bend decrease by 3.7%, 8.8%, and 7.5%, respectively, with local peak reductions exceeding 250 K. The study demonstrates that the YSZ TBCs enhances the combustor’s thermal protection capability, flow stability, and temperature uniformity through a coupled mechanism of “thermal insulation–flow reconstruction–energy redistribution.” It should be noted that this study considers only the effect of the ceramic top coat of the TBCs, excluding the metallic bond coat and the thermally grown oxide (TGO) layer. Full article

The emergence and global dissemination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-E. coli) represent a major public health concern. However, the characterization and capacity for horizontal gene transfer (HGT) of ESBL-E. coli in captive black bears remain substantially understudied. In the present study, 19 ESBL-E. coli strains were successfully identified (13.38%, 19/142). A total of 11 sequence types (STs) were identified from 19 ESBL-E. coli strains using MLST. This included eight known types (ST10, ST2690, ST208, ST695, ST4160, ST540, ST3865 and ST2792) and three new STs. Antimicrobial susceptibility testing demonstrated that all 19 ESBL-E. coli exhibited high resistance to KZ (100.00%), CRO (78.95%), and CTX (73.68%). Polymerase chain reaction (PCR) screening for 14 β-lactam antibiotic resistance genes (ARGs) and their variants revealed that bla_CTX-M was the most prevalent, followed by bla_SHV, bla_TEM, and bla_DHA. Furthermore, eight β-lactamase variants were detected, including five bla_CTX-M variants (bla_CTX-M-15, bla_CTX-M-3, bla_CTX-M-14, bla_CTX-M-55, and bla_CTX-M-27) and one variant each of bla_SHV-1, bla_TEM-1, and bla_DHA-14. Conjugation assays revealed that eight ESBL-E. coli strains were capable of conjugative transfer. Five plasmid types (IncFII, IncW, IncFrepB, IncY, and IncHI1) and three mobile genetic elements (MGEs) (IS26, ISEcp1, and trbC) were identified as co-transferred with bla_CTX-M. ESBL-E. coli poses a potential threat to captive black bears and may lead to further transmission. Consequently, the implementation of continuous surveillance and targeted interventions is imperative to prevent the transmission of ESBL-E. coli. Full article

This work focuses on the investigation of ten newly synthesized spironaphthoxazines using DFT to elucidate how substituents control physicochemical behavior. Frontier-orbital analyses show substituent changes primarily shift the LUMO, controlling HOMO–LUMO gaps and electrophilicity; the open forms (MC) structures exhibit smaller gaps than closed spiro forms (SP) due to extended conjugation. Simulated IR/Raman spectra provide diagnostic markers for structural assignment. Thermodynamic parameters (S, Cp, H, G; 200–500 K) reveal higher S and Cp for MC and for longer alkyl chains, yielding lower G at elevated temperatures. Transition-state calculations indicate accessible SP↔MC isomerization barriers, confirming accessible switching. These results offer a predictive framework to position functional groups and tailor optical response, switching kinetics, and stability for responsive materials. Full article

Fluorescent proteins find application as biocompatible, genetically encoded labels for visualization of living organisms tissues. Green fluorescent proteins (GFPs) are the most diverse, but proteins with red fluorescence have advantages, such as lower phototoxicity and better penetration into biological tissues. A promising approach is to obtain red fluorescent proteins (RFPs) from GFPs by introducing mutations that stabilize the oxidized chromophore state with an extended conjugated π-system. However, to date this remains a non-trivial task and experimental developments are carried out mainly by random mutagenesis. Development of descriptors obtained in molecular modeling can rationalize this field. Herein, we rely on experimental data on the AzamiGreen fluorescent protein and its variants that are oxidized to the red form. We perform classical molecular dynamics (MD) and combined quantum mechanics/molecular mechanics (QM/MM) simulations to determine structural and dynamic features that govern oxidation. We demonstrate that the red state is predominantly stabilized by interactions of polar lysine residues with chromophore oxygen atoms. Dynamic network analysis demonstrates that in red fluorescent proteins the chromophore motions are correlated with the movement of surrounding protein side chains to a higher extent than in green variants. The presence of different resonance forms of the chromophore determines the fluorescence band maximum value: a decrease in the phenolate form population leads to the red shift. Full article

Dicyanovinyl (DCV) oligothiophenes are interesting materials due to their unique optical and electronic properties. They are relatively easy to prepare using Knoevenagel condensation reactions from the corresponding aldehydes. Understanding their optical and electrochemical characteristics is important for both building structure/property relationships and for optimizing their performance in various applications. We report on the electrochemical and photophysical properties of three oligothiophenes end-capped with dicyanovinyl -CH=C(CN)₂ or DCV groups. The compounds included in this study are DCV-T-DCV (1), DCV-2T-DCV (2), and DCV-3T-DCV (3), where T represents one thiophene unit. Introduction of the DCV groups into oligothiophenes results in unique evolution of their electrochemical and optical behavior. First, new reversible two-electron reduction processes in the series DCV-nT-DCV start to appear with a gradual increase in the reduction potential with an increasing number of thiophene units. This was consistent with the electronic spectroscopic results. These results demonstrate that the DCV groups can be used in molecular design and fine-tuning of the optical and redox properties of oligothiophene and presumably this strategy can be extended to other conjugated organic molecules. We also report on the photophysical and vibrational spectroscopic properties of these compounds. The C=C stretching bands in Raman and IR spectra reveal more quinoidal nature in shorter molecules and more dominant benzoidal character in longer molecules. The DCV-induced modulation of electrochemical, optical, and vibrational properties highlights their potential in diverse optoelectronic applications. Full article

Polycyclic aromatic hydrocarbons (PAHs) play a central role in materials science due to their extended π-conjugated systems, with their stability and reactivity depending critically on their aromatic character. In this work, we systematically investigated the aromaticity and stability of a broad range of linear (acenes, phenacenes, biphenylenes, and cyclobuta-acenes) and belt-like (cyclacenes, cyclophenacenes, and cyclobiphenylenes) PAHs containing five to twelve benzene rings. A diverse set of aromaticity descriptors was employed, including geometric (HOMA), electronic (MCI, FLU) and magnetic (NICS) descriptors, plus the recently developed ${\mathit{Q}}_2$ indices, based on the components of the distributed multipole analysis (DMA) electric quadrupole tensor. These data were complemented by stability analyses using singlet–triplet energy splitting (ΔE_S–T) and fractional occupation number-weighted densities (N_FOD) values. Our results indicate that acenes and phenacenes follow a comparable aromatic trend, with inner rings possessing lower aromaticity and the edge rings showing a more pronounced aromatic character. A subtle difference is observed in the position of the most aromatic ring, which lies slightly closer to the interior in acenes. Phenacenes, however, exhibit greater overall stability, attributed to their armchair edges. For biphenylenes and cyclobuta-acenes, the antiaromatic cyclobutadiene moiety perturbs the aromaticity only in its direct neighborhood and preserves the aromaticity in the remaining chains. In belt-like systems, cyclacenes exhibit strong radical character and low stability, consistent with longstanding synthetic challenges, whereas cyclophenacenes display enhanced aromaticity and stability with extending size. Cyclobiphenylenes combine localized antiaromatic centers with preserved benzene-like aromaticity in rings distant from the cyclobutadiene unit. Full article