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Boron is a chemically distinctive bioelement whose electron-deficient structure enables reversible coordination with oxygen-rich functional groups such as diols and hydroxyls. This property allows boron to modulate molecular stability, conformation, and biological reactivity, giving rise to both beneficial pharmacological effects and toxicological outcomes. This review examines the dual biological role of boron through the framework of bioactive boron-containing natural products and natural compounds capable of forming reversible boron complexes. Particular attention is given to naturally occurring boron-containing antibiotics, including the polyketide macrodiolides boromycin, aplasmomycin, tartrolons, and hyaboron, where boron plays a direct structural and functional role in antimicrobial activity. These compounds demonstrate how boron coordination can influence ion transport, membrane interactions, and molecular assembly, contributing to potent antibacterial properties. Beyond intrinsically boron-containing metabolites, many natural antibiotics and toxins possess oxygen-rich architectures capable of forming transient borate complexes through vicinal 1,2-diol motifs. Examples include polyene macrolide antibiotics such as amphotericin B, fungichromin, and nystatin, as well as tetracyclines, rifamycins, and macrolides such as sorangicin A, where boron coordination may affect solubility, aggregation, ionophoric behavior, and biological selectivity. Similar chemistry is observed in marine neurotoxins and polyether toxins—including tetrodotoxin, saxitoxin derivatives, azaspiracids, pectenotoxins, ciguatoxins, and gambierones—whose hydroxyl-rich frameworks enable reversible interactions with boron species present in seawater. Such complexation may enhance aqueous stability and contribute to trophic transfer and bioaccumulation within marine ecosystems. By framing boron as a molecular “double edge,” this review integrates chemical, biological, and environmental perspectives to highlight how boron coordination can simultaneously enhance antimicrobial activity while influencing toxicity and ecological persistence. Recognizing the role of boron in shaping the activity of natural products provides new insight into antibiotic function, toxin behavior, and the broader impact of boron chemistry in biological systems. Full article

This review examines the historical development, ethnopharmacology, traditional applications, phytochemistry, and pharmacological attributes of Atractylodis Rhizoma (AR). Data were collected from a range of electronic databases, academic libraries, and classical literature. In China, AR is highly valued for its medicinal properties. Research has identified 327 compounds, including sesquiterpenes, triterpenes, flavonoids, and phenolics, which contribute to its diverse pharmacological activities, such as antimicrobial, anti-inflammatory, antioxidant, hepatoprotective, and neuroprotective effects. AR is particularly effective in treating modern gastrointestinal disorders and influenza. As a traditional herb with a rich historical background, AR exhibits significant therapeutic potential. This review aims to correlate its active components with its primary therapeutic effects and highlight existing research gaps. Current studies primarily focus on extraction methods and pharmacodynamics. Future research should employ multi-omics and molecular biology techniques to further elucidate active components and their targets, while also addressing the challenge of low bioavailability. Full article

Background: Dental students need to qualify with a clear understanding of the continuum of biological development from the molecular (genetic, epigenetic and environmental interactions) to the cellular (morphogenesis and differentiation) to the emergence of the mature tissue or organ. Histogenetics provides a core component for this understanding. The aim of this study is to investigate whether a merged approach, combining traditional and recent methods, can enhance the teaching of histogenetics to dental students. Methods: This study blended traditional (lectures, drawings, microscopy) and recent approaches (flipped classroom elements, virtual microscopy, group-based poster construction, and interactive quiz-based discussion) to enhance student engagement and perceived learning in oral histogenetics. The intervention was delivered to master-level dental students across six core oral histogenetics topics. Teaching followed a structured three-phase model: Prepare (digital lectures and short microscopy-introduction videos); Engage (microscopy session and group-based poster creation); and Test and Discuss (teacher-led quizzing and discussion). Student perceptions were evaluated through an electronically distributed 17-item questionnaire at the end of the course. Items were grouped into self-evaluation, resources, and teaching method domains and rated on a five-point Likert scale. Results: A total of 45 of 51 students responded (88%). Across all domains, positive perceptions (Agree/Strongly Agree) predominated (p < 0.001). Self-evaluation items showed strong agreement for attendance and group contribution, with more variability in preparation time and motivation. Resources were rated highly, although the accessibility of physical guidance showed more mixed responses. The merged teaching method received strong endorsement, with students reporting engagement, enjoyment, ease of understanding, and clear emphasis on clinical relevance. Conclusions: The merged approach was perceived as pedagogically valuable and clinically meaningful by the students and appears to enhance perceived engagement, clarity, and relevance in oral histogenetics teaching. These findings support the adoption of blended, student-active methodologies to strengthen comprehension and promote clinically meaningful learning in oral histology. Full article

Lactoferrin (Lf) and Lf-derived peptides are multifunctional milk components with potential applications in food preservation due to their antibacterial and antioxidant properties. In this study, the antibacterial and antioxidant activities of bovine lactoferrin and Lf-derived peptides obtained by enzymatic hydrolysis with pepsin, trypsin, and chymotrypsin were evaluated. Antibacterial activity was assessed against four foodborne pathogens and spoilage microorganisms (Escherichia coli, Listeria monocytogenes, Staphylococcus epidermidis, and Latilactobacillus sakei), while antioxidant activity was determined using four complementary assays. Lf showed stronger antibacterial activity than the corresponding hydrolysates against all tested strains, while the hydrolysates notably inhibited Listeria monocytogenes and Latilactobacillus sakei. Both Lf and its peptides showed lower antioxidant capacity than Trolox, although native Lf and its peptides markedly inhibited lipid peroxidation. Lf peptides demonstrated greater antioxidant activity in the superoxide scavenging and FRAP assays. Low-molecular-weight peptides (<10 kDa) contributed most to antioxidant activity, while mass spectrometry analysis revealed peptide sequences rich in hydrophobic and electron-donating amino acid residues, providing mechanistic insight into the observed activities. Overall, these findings highlight the potential of lactoferrin and its enzymatic hydrolysates as natural antimicrobial and antioxidant agents for food preservation. Full article

Neurodegenerative diseases share a mitochondrial–immune axis in which impaired oxidative phosphorylation reshapes neuronal metabolism and drives chronic inflammation. Complex I play a redox gatekeeper role at the coenzyme Q (CoQ) junction: catalytic defects, misassembly, or reverse electron transport over-reduce the CoQ pool, increase electron leak, and elevate ROS. How respiratory supercomplex plasticity (CI-CIII₂, CIII₂-CIV_n, or CI-CIII₂-CIV_n) modulates carrier channelling, flux control, and ROS propensity through dynamic reorganization of the electron transport chain is highlighted. Excess ROS damages lipids and mitochondrial DNA, promoting the release of mitochondrial damage-associated molecular patterns s that activate NLRP3 inflammasome signalling, cGAS-STING-dependent interferon programs, and endosomal TLR9 pathways, establishing feed-forward loops between mitochondrial injury and neuroinflammation. Disease-focused sections integrate evidence from Parkinson’s, Alzheimer’s, amyotrophic lateral sclerosis, and Huntington’s models, and map these mechanisms onto therapeutic opportunities spanning electron transport chain support, supercomplex stabilization, and consider mtDNA-sensing inflammatory nodes. Full article

Background/Objectives: Psychological stress triggers excessive melanin deposition via neuroendocrine pathways, yet targeted interventions for stress-induced hyperpigmentation remain limited. Salidroside (SAL) exhibits established depigmenting effects in UV-induced models and possesses neuroprotective properties. This study investigated SAL’s efficacy in psychological stress-induced hyperpigmentation and elucidated its underlying mechanisms. Methods: B16F10 melanocytes, C57BL/6J mice, zebrafish, and human foreskin organ cultures were subjected to stress factor (Substance P/cortisol) or α-MSH/IBMX stimulation to model psychological stress-induced and canonical cAMP-driven hyperpigmentation, respectively. Melanin content, tyrosinase activity, melanosome maturation (transmission electron microscopy/HMB45 staining), and melanogenic protein/mRNA expression were assessed. Drug Affinity Responsive Target Stability (DARTS) assays, molecular docking, and SEC23A siRNA knockdown were employed to identify and validate SAL’s molecular target and downstream signaling pathways. Results: SAL dose-dependently reduced melanin content, tyrosinase activity, and TYR/TRP-1/DCT expression in SP/Cort-stimulated melanocytes, exhibiting greater potency (200 μM) than in IBMX-induced models (400 μM). SAL reversed SP/Cort-induced hyperpigmentation in human skin explants, zebrafish, and C57BL/6J mice, and normalized melanosome number/maturation. DARTS and molecular docking identified SEC23A as a direct SAL-binding target. SP/Cort specifically upregulated SEC23A, which SAL suppressed. SAL concurrently activated the SEC23A-p-ERK-MITF axis and inhibited the NK1R-p38-MITF axis in the stress model. SEC23A knockdown potentiated SAL’s anti-melanogenic effects specifically in SP/Cort-stimulated cells. Conversely, in IBMX-induced models, SEC23A remained unchanged, and SAL acted via PKA/CREB, PI3K/AKT, and Wnt/β-catenin pathways. Conclusions: SEC23A is a novel core target in psychological stress-induced hyperpigmentation. SAL selectively binds SEC23A to inhibit stress-induced melanogenesis via dual ERK and p38 MAPK signaling axes, demonstrating etiological specificity distinct from canonical cAMP pathway inhibition. Full article

Controlling thermodynamic properties is critical for the rational design and development of advanced lead-free solders, especially in high-temperature applications. Au–Sn-based alloys have emerged as promising candidates for high-performance electronic packaging, yet reliable thermodynamic descriptions of their multicomponent systems remain limited. The Modified Molecular Interaction Volume Model (M-MIVM) provides a effective approach for characterizing strongly asymmetric liquid alloys that are typical in Au–Sn-based systems. This work focuses on the thermodynamic modeling of Au–Sn-containing ternary and quaternary solder systems within a physically consistent and computationally efficient framework. The study aims to support the database development, composition design, and optimization of next-generation high-temperature lead-free solders. Full article

Atomic charges are widely used to analyze molecular electronic structure and substituent effects, yet their numerical values and interpretations are inherently dependent on the adopted density partitioning scheme. Here, we adapt the Equivariant Atomic Contribution framework to molecular systems (EAC-qm), enabling prediction of atom-resolved continuous charge densities from which atomic charges are obtained as spatial moments. The predicted densities reproduce reference density functional theory results with high accuracy and preserve global charge conservation. To assess chemical interpretability, we examine charge responses in monosubstituted aromatic systems using Hammett substituent constants as external empirical references. Atomic charges derived from EAC-qm exhibit a strong linear association with Hammett parameters, compared with values obtained from traditional density partitioning approaches applied to the same electronic structures. These correlations indicate that density-derived charges respond systematically to established substituent electronic trends. Beyond scalar charges, atom-resolved dipole moments can be evaluated as first-order moments of the same continuous density representation. Illustrative examples for formaldehyde (H₂CO) and formamide (HCONH₂) show that local dipole vectors provide directional information about intra-atomic polarization that is not captured by point-charge models. Overall, the results suggest that machine-learned continuous electron densities provide a representation-consistent basis for constructing atom-centered electronic descriptors with chemical interpretability. Full article

Glutathione (GSH) is a central regulator of redox homeostasis, melanogenesis, and cellular repair, and has gained increasing attention in dermatology for its potential roles in skin brightening, anti-aging, and tissue regeneration. This systematic review evaluated molecular, clinical, and translational evidence of glutathione’s applications and safety across different delivery modalities. The review followed PRISMA guidelines and included studies published between 2000 and 2025. A total of 194 studies met the inclusion criteria, evaluating the effectiveness of glutathione in esthetic dermatology and regenerative medicine. Topical and oral glutathione demonstrated favorable effects on pigmentation, skin brightness, hydration, and oxidative stress markers. Injectable glutathione increases systemic levels rapidly, but is associated with short-lasting effects and potential safety concerns. Glutathione S-transferases facilitate the conjugation of glutathione to electrophilic xenobiotics, thereby protecting proteins and nucleic acids from electrophile-induced damage. Glutathione Peroxidase employs GSH as an electron donor to reduce hydrogen peroxide and lipid hydroperoxides, thus protecting membrane lipids, mitochondrial membranes, and DNA from oxidative damage. Glutathione facilitates the regeneration of other antioxidants, such as vitamin C and vitamin E, through redox cycling. A consistent correlation exists between reduced GSH levels and neuronal dysfunction. Elevated GSH levels enhance cellular resistance to oxidative stress and reduce apoptotic signaling. GSH plays a pivotal role in cutaneous aging and tissue repair through redox regulation, mitochondrial protection, and the modulation of inflammatory and extracellular matrix pathways. To elucidate the clinical significance of glutathione, future research should focus on conducting randomized controlled trials, developing standardized formulations, and performing long-term safety assessments. Full article

Leishmaniasis is a global health issue, especially in tropical and subtropical areas, with treatment challenges due to the development of resistance to current drugs. This has prompted the search for new antileishmanial compounds. Endoperoxides, due to parasites’ reliance on external iron and susceptibility to oxidative stress, are promising antileishmanial compounds. This study evaluated two sterol endoperoxides—ergosterol endoperoxide (ErgoEP) and dehydrocholesterol endoperoxide (DHCholEP)—for their antileishmanial activity and mechanism in vitro. Cell viability assays with Leishmania donovani and Leishmania tarentolae promastigotes showed IC₅₀ values in the low micromolar range (from 2.0 to 4.5 µM, respectively) with low toxicity to murine and J774A.1 macrophages. Electron paramagnetic resonance spectroscopy confirmed radical generation in the presence of low-molecular-weight iron compounds. However, this did not trigger the antileishmanial effect, as neither N-acetylcysteine nor pyridoxal isonicotinoyl hydrazone altered activity. Mitochondrial function(s) and superoxide production in Leishmania remained unaffected. Both endoperoxides significantly inhibited synthesis of 5-dehydroepisterol, the major sterol in Leishmania tarentolae, suggesting targeting of the sterol biosynthesis pathway. Their limited toxicity to mammalian macrophages makes ergosterol and dehydrocholesterol endoperoxides promising candidates for future antileishmanial drug development. Full article

The current research investigates the electrochemical performance of plasticized nanocomposite solid polymer electrolytes derived from a polyethylene oxide (PEO)–polymethyl methacrylate (PMMA) blended system with lithium iodide (LiI) as the dopant salt and tin dioxide (SnO₂) nanoparticles as the inorganic nanofillers. Thin nanofilms of the synthesized electrolytes were prepared and progressively examined by using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Ultraviolet visible (UV–Vis) spectroscopy, and Scanning electron microscopy (SEM). XRD characterization confirmed the successful establishment of the polymer electrolyte matrix and reflected a significant decrease in crystallinity upon the incorporation of nanofillers, whereas crystallite size was estimated using the Debye–Scherrer equation. FT-IR spectra showed prominent molecular interactions and complexation of polymer, salt, and nanofiller components. UV–Vis spectroscopy provides information on the optical absorption behavior, whereas the SEM micrograph shows the morphological features and homogeneity of plasticized nanocomposite solid polymer electrolyte films. The addition of SnO₂ nanofillers was shown to improve both the structural and electrochemical properties of the electrolyte system, highlighting its potential usage in solid-state batteries and other high-end electrochemical devices. These enhancements make the developed nanocomposite solid polymer electrolytes viable candidates for high-performance, flexible lithium-ion battery applications, offering a promising route toward safer and more efficient energy storage systems. Comprehensive electrochemical performance evaluation will be addressed in future studies. Full article

Wheat is rich in carbohydrates and proteins but is susceptible to pest infestation and microbial contamination during storage. Owing to itself high efficiency, energy savings, and lack of chemical residues, electron beam irradiation (EBI) has been widely applied for disinfesting and sterilizing cereals and has been shown to influence dough quality. Notably, starch is present within complex wheat flour systems during processing, and its irradiation response may differ from that of purified systems. In this study, the effects of different EBI doses (0, 3, 6, 9 and 12 kGy) on the multiscale structure and physicochemical properties of wheat starch isolated from irradiated dough were systematically investigated, and key analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and rheological analysis were employed to elucidate the mechanisms underlying its impact on the dough thermomechanical behavior of dough. The results demonstrated that EBI weakened gluten–starch interactions and disrupted gluten network the continuity and compactness of the gluten network, resulting in significant dough farinography and pasting property changes. Compared with those of the control group, the dough development and stability time of the 12 kGy sample decreased from 3.920 and 6.465 to 0.970 and 1.290, respectively (p < 0.05). Moreover, irradiation induced cracks on the starch surface, reduced its molecular weight, and disrupted its crystallinity and short-range order. These changes resulted in decreases in the thermal stability level and swelling capacity of starch, while increasing its solubility. A correlation analysis revealed that the starch chain length distribution, molecular weight, molecular order, and pasting properties are key determinants of EBI-induced dough quality changes. This study provides theoretical insights into the applicability of EBI in the context of wheat flour storage and quality modulation. Full article

Prolonged occupational exposure to oil mist particulate matter (OMPM) poses health risks, yet its neurotoxic effects and underlying mechanisms remain poorly understood. Here, OMPM generated from turbine oil commonly used in occupational labor environments was used to expose rats. The rats were divided into the control and OMPM groups. Following 42 days of exposure, a multidimensional assessment was performed using untargeted metabolomics, phosphoproteomics, behavioral testing, hematoxylin–eosin (HE) staining, transmission electron microscopy (TEM), colorimetric assays, enzyme-linked immunosorbent assay, and Western blotting (WB) to evaluate metabolic alterations, protein phosphorylation, and tissue integrity in the striatum. Integrated omics analyses revealed that differentially phosphorylated proteins and metabolites were remarkably enriched in dopaminergic synapse, Parkinson’s disease, and amphetamine addiction pathways (FDR < 0.05), with a regulatory axis involving L-tyrosine, tyrosine hydroxylase (TH), and dopamine (DA) identified. OMPM-exposed rats exhibited depression- and anxiety-like behaviors, alongside striatal pathological and ultrastructural damage. Biochemical analyses showed elevated malondialdehyde and reactive oxygen species levels; reduced superoxide dismutase, glutathione, and glutathione peroxidase activities and total antioxidant capacity; increased glutathione disulfide and inducible nitric oxide synthase expression; and decreased DA and L-tyrosine levels. Additionally, proinflammatory mediators (IL-1β, IL-6, TNF-α, MCP-1, and PGD₂) were significantly upregulated in the striatum. WB analysis further confirmed significant reductions in the relative phosphorylation levels of key regulators in dopaminergic and calcium signaling pathways, including CALM3, CaMK2b, GSK-3β, PRKCG, and TH. Collectively, these findings reveal critical molecular and biochemical alterations in the rat striatum following OMPM exposure and provide a mechanistic basis for understanding depression-like behaviors associated with prolonged OMPM exposure in occupational workers. Full article

H-NS (histone-like nucleoid-structuring protein) is a global regulator affecting diverse bacterial processes. This study aimed to elucidate the regulatory role of H-NS in the virulence of Klebsiella pneumoniae (K. pneumoniae), particularly in relation to capsule synthesis and anchoring. A clinically isolated ST11-KL64 strain of K. pneumoniae FK6741 with low virulence was used. The role of H-NS was evaluated using colony morphology, the string test, viscosity measurement, capsule quantification, transmission electron microscopy, growth curve, biofilm assay, a mouse infection model, transcriptomic analysis, and RT-qPCR. Deletion of hns converted FK6741 into a hypermucoid phenotype in the positive string test; capsule quantification and transmission electron microscopy (TEM) showed increased polysaccharide chains but a reduced and tightly bound capsule. The mutant was initially found to grow slowly but formed stronger biofilms. In vivo, it displayed reduced virulence but induced stronger inflammation. Molecular assays revealed upregulation of capsule synthesis genes (galF, wzi, wcaJ, and wzc) and downregulation of wabG, which is involved in capsule anchoring. H-NS represses capsule synthesis genes, limiting capsule formation in K. pneumoniae. In contrast, loss of H-NS downregulates wabG, a key gene involved in GalA-mediated capsule anchoring, resulting in unstable surface attachment and loss of capsular polysaccharides. Consequently, these unanchored polysaccharides fail to confer effective protection, resulting in reduced bacterial virulence. Full article

Oxygenic and anoxygenic photosynthesis are initiated through the absorption of light by chlorophyll and bacteriochlorophyll photosynthetic pigments, respectively, which function as light-harvesting (antenna) and redox pigments on the photosynthetic membrane that trap and convert the absorbed optical energy into chemical energy. While several studies have characterized the ultrafast spectra, kinetics, and structures of the light-harvesting and reaction center complexes that contain the photosynthetic pigments, a detailed understanding of how the ultrafast excited-state dynamics vary across different photosynthetic pigments is lacking. Such information is critical in understanding the molecular mechanisms of both artificial and natural photosynthetic systems. In this study, we conducted ultrafast time-resolved absorption spectroscopy on chlorophyll and bacteriochlorophyll photosynthetic pigments at room temperature to directly compare the spectra and kinetics of their transient, excited electronic states formed following photon absorption. The recorded ultrafast spectral and kinetic data, spanning the femtosecond to sub-microsecond timescales, show interesting similarities and differences between these two distinct types of photosynthetic pigments. These experimental results help clarify the relationship between photosynthetic pigment structure and the resultant ultrafast processes in the oxygenic and anoxygenic photosynthetic reaction mechanisms. Full article