Search Results (1,591)

Rosa roxburghii Tratt is recognized as an edible and medicinal plant valued for its nutritional and medicinal properties. Polysaccharides are among its key bioactive constituents. A homogeneous polysaccharide, designated RTW-1, was extracted and purified from the fruit of Rosa roxburghii Tratt. Its molecular mass was determined by HPLC to be 2.16 × 10³ kDa. Monosaccharide composition and methylation analysis showed that RTW-1 is mainly composed of glucose, arabinose, and galacturonic acid in a molar ratio of 1.00:0.48:0.74. The uronic acid content was measured as 55.21%, and the degree of esterification was 58.30%. The glycosidic linkages identified included (→2,3,4)-Manp-(1→, →4)-Arap-(1→, →4)-GalAp-(1→, T-Rhap, →4)-Glcp-(1→, and (→2,3,4)-Xylp-(1→). Shear-thinning behavior was revealed by rheological analysis. At 30 mg/mL, the thixotropic loop area reached 143.8 Pa/s, which was 20 times higher than that at 12 mg/mL. In RAW264.7 macrophages, cell proliferation was promoted by RTW-1. At 80 μg/mL, phagocytic activity was increased by 88%, and NO production was enhanced by 3.1-fold. Concentration-dependent upregulation of TNF-α, IL-6, IL-1β, and IL-10 mRNA expression was observed by qRT-PCR, with maximum increases of 3.2-, 4.1-, 2.8-, and 2.5-fold, respectively. In conclusion, RTW-1 possesses favorable gel-forming and immunostimulatory properties and shows potential for promoting intestinal immune activity, suggesting its promise as a functional food ingredient. Full article

Polyalphaolefin (PAO)-based magnetic fluids are widely used in precision transmission systems for their excellent rheological and lubricating properties, but their stability and magnetic controllability under high-temperature and high-shear conditions remain a key challenge. In this work, a PAO2-based magnetic fluid was prepared via coprecipitation using a sequential modification strategy involving oleic acid and alkenyl succinimide. An energy competition model under multi-field coupling was established using the magnetothermal energy ratio ($\lambda$) and Mason number ($Mn$) to elucidate the system’s rheological behavior. The fluid shows significant shear-thinning behavior under zero magnetic field; a 60 kA/m magnetic field increases the relative viscosity by over 4 times at 5 s⁻¹, while the magnetoviscous effect becomes weak at shear rates over 500 s⁻¹ (corresponding approximately to $Mn$= 1). With increasing temperature, the field-induced viscosity enhancement decreases progressively as thermal disturbance becomes increasingly important. This work reveals the multi-field coupling rheological mechanism, and the results suggest that the OA/T154 modification strategy is a feasible route for obtaining a PAO-based magnetic fluid that remains dispersible and magnetically responsive under the tested conditions. The study provides theoretical and experimental support for the design of intelligent lubricating materials. Full article

Arachidonate 5-lipoxygenase (ALOX5) is a key enzyme implicated in several inflammatory disorders, including asthma and allergic rhinitis. Despite its therapeutic importance, only one compound is currently approved as an ALOX5 inhibitor in the United States, highlighting the urgent need for new drug candidates. Progress in this area is often hindered by conventional bioassays, which can be labor-intensive, costly, and unsuitable for complex mixtures. To overcome these challenges, we developed a simple thin-layer chromatography (TLC) bioautographic assay for the rapid detection of ALOX5 inhibitors in natural extracts, a rich source of pharmacologically active compounds. The method exploits the oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone (MBTH) with 3-(dimethylamino)benzoic acid (DMAB) during the ALOX5-catalyzed conversion of arachidonic acid, producing a colored indamine dye. Experimental parameters influencing chromogenic reaction were investigated and optimized to minimize reagent consumption while ensuring accuracy and sensitivity of the method. The assay was then applied to a panel of natural products and to crude mushroom extracts, enabling the rapid identification of several active compounds within complex extracts, including the dual COX2/ALOX5 inhibitor 3α-acetylpolyporenic acid A. Easy to implement, cost-efficient, and well suited for screening and bioguided fractionation, this TLC bioassay provides a powerful tool to accelerate the discovery of novel anti-inflammatory compounds. Full article

Chia seed mucilage (CSM) is a promising plant-derived hydrocolloid characterized by unique physicochemical and functional properties that are strongly influenced by the extraction methodology. In this research, an optimized sonication–freezing-assisted extraction (SFAE) process was developed to obtain mucilage while preserving its structural integrity. Results indicate that the extracted mucilage has a high total dietary fiber content of 75.87% and a moderate protein level of 8.71%. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of hydroxyl and ionized carboxylate (COO⁻) groups associated with uronic acids, highlighting the anionic and polyelectrolyte nature of the system. Rheological characterization of optimized-CSM revealed Newtonian behavior in dilute solutions, indicating minimal intermolecular interactions and permitting accurate measurement of intrinsic viscosity and viscosity-average molecular weight. A critical overlap concentration (c** ≈ 0.2% w/v) was identified, marking the transition to semi-dilute regimes, chain entanglement, and the onset of shear-thinning and viscoplastic behavior. Functionally, the optimized-CSM exhibited high water holding capacity and competitive emulsifying properties (emulsion activity index (EAI): 62.50%; emulsion stability index (ESI): 49.32%), attributed to synergistic interactions between proteins and polysaccharides. Overall, this work provides new insights into how processing conditions influence the chemical composition and molecular structure, which fundamentally govern the rheological and functional performance of CSM. These findings underscore its potential as a versatile hydrocolloid for food and biomedical applications. Full article

Ruthenium (Ru) and its alloys exhibit high corrosion resistance in acidic environments; however, their corrosion behavior in supercritical acidic fluids remains unclear. In this study, the corrosion resistance of Ru–Mo–W and Ru–Mo–Fe–Cr alloy systems in supercritical nitric acid was evaluated using a combinatorial approach. Alloy thin-film libraries with a thickness of approximately 300 nm were fabricated on (001) sapphire substrates by multi-target magnetron sputtering. Composition and thickness were evaluated by X-ray fluorescence (XRF) before and after corrosion testing. The composition-dependent corrosion behavior was compared in a 0.2 M nitric acid solution at 400 °C and 30 MPa. In the Ru–Mo–W system, most Ru-rich compositions exhibited corrosion rates below 0.2 mm/y, and at comparable Ru contents, Mo addition provided higher corrosion resistance than W addition. In the Ru–Mo–Fe–Cr system, significant dissolution and film delamination were observed on the low-Ru side. These results demonstrate that the combination of combinatorial thin-film libraries and XRF-based thickness evaluation is an effective first-stage approach for identifying promising alloy composition regions in supercritical acidic environments. Full article

Cathodic electrodeposition of copper on molybdenum and stainless-steel substrates has been investigated with the aim of examining their potential to produce thin copper foils (TCFs). Copper in the form of a thin film was electrodeposited galvanostatically from the acidic sulfate electrolyte without and with an addition of suppressor/activator additives, such as chloride ions, polyethylene glycol 6000 and 3–mercapto–1–propanesulfonic acid. The cathodes and electrodeposited Cu films were characterized by SEM, AFM, and XRD techniques, while the adhesion of Cu films, as a crucial parameter in the production of Cu foils, was estimated by a lab-made prototype of a bending test machine made by applying additive technology. The adhesion parameter named “critical cycle number” (n_c), which defines the minimal number of cycles leading to a delamination (separation) of the film from the cathode was used for assessing the adhesion features of the films. The easiest delamination, i.e., the smallest n_c, showed nanocrystalline films obtained with the addition of all additives, whereupon the values were significantly smaller than the values obtained for microcrystalline films obtained without and with a partial combination of the additives. The easy delamination of the nanocrystalline films indicated that both substrates have a high potential for application in the production of TCFs. Full article

Alzheimer’s disease (AD) is increasingly recognized as a multisystem neurodegenerative disorder in which sensory dysfunction accompanies cognitive decline. As an accessible extension of the central nervous system, the retina provides a valuable window for investigating early neurodegenerative processes; however, the cellular mechanisms underlying AD-associated retinal pathology remain incompletely understood. Here, using the APP/PS1 mouse model, we systematically examined structural, functional, and glial alterations in the retina across disease stages. Despite robust age-dependent amyloid plaque accumulation in visual-related brain regions, no plaque-like β-amyloid (Aβ) deposits were detected in the retina even at advanced ages. Nevertheless, young APP/PS1 mice exhibited early thinning of inner retinal layers, impaired retinal electrophysiological responses, and reduced excitatory synaptic inputs to retinal ganglion cells (RGCs), preceding overt neuronal loss. These neuronal changes were accompanied by pronounced Müller glial activation, characterized by upregulation of gliosis markers and extensive morphological remodeling. Functional analyses further revealed dynamic alterations in glial homeostasis, including early elevation followed by age-dependent decline of glutamine synthetase activity, together with increased expression and disrupted perivascular polarity of aquaporin-4. Consistently, transcriptomic profiling of young AD retinas identified coordinated dysregulation of genes involved in amino acid metabolism, transport, and oxidative stress responses. Together, our findings identify Müller glial remodeling as an early feature of AD-associated retinal pathology that coincides with synaptic vulnerability of RGCs and occurs independently of local Aβ plaque deposition, highlighting retinal glia as potential early indicators and modulators of neurodegeneration. Full article

This study compared oat yoghurt (OY), almond yoghurt (AY), oat–almond yoghurt (OAY), and an unfermented oat–almond milk (OAM) to clarify how blending and lactic fermentation affect fermented plant-based alternatives to yoghurt. Nutritionally, OAY showed a balanced profile (protein 2.87 g/100 g; fat 5.18 g/100 g), intermediate between AY (3.29 g/100 g, 8.89 g/100 g) and OY (2.39 g/100 g, 3.30 g/100 g). Fermentation enhanced physical stability, as OAY showed higher water-holding capacity (58.08%) and high viscosity (5381.49 mPa·s), together with the highest viable lactic acid bacteria count (7.1 log10 CFU/g). Scanning electron microscopy revealed that co-fermentation formed a denser, more cohesive multiphase gel network with reduced pore size compared with OAM and AY. All samples exhibited shear-thinning behavior; dynamic rheology indicated weak gel features (G′ > G″), and OAY showed the highest G′, implying a reinforced network likely associated with interactions between oat β-glucan and almond proteins during fermentation. Volatile profiling by GC–MS identified 117 compounds, and OAY exhibited the greatest total volatiles (523.02 μg/kg), exceeding OY (397.43 μg/kg) and OAM (195.73 μg/kg), indicating improved aroma complexity and consumer acceptability. In conclusion, our study will provide quantifiable formulations for the development of highly acceptable oat and almond-based plant-based yoghurt. Most importantly, it also offers additional dairy products for individuals with gluten allergies and lactose intolerance. Full article

Dopamine (DA) is a crucial catecholamine neurotransmitter, and its abnormal levels are closely associated with neurological disorders such as Parkinson’s disease. Electrochemical sensing technology offers a rapid and cost-effective platform for DA detection; however, it often suffers from interference from coexisting biomolecules such as ascorbic acid (AA) and uric acid (UA). In this study, we report a novel electrochemical biosensor based on PdMo bimetallene, a nanomaterial synthesized via a facile wet-chemical approach, aiming to enhance the detection performance and selectivity for DA. PdMo bimetallene is a highly curved, atomically thin two-dimensional nanosheet featuring abundant strained sites and a high density of active centers, enabling the selective and sensitive detection of DA. The results demonstrate that the as-prepared PdMo bimetallene-modified glassy carbon electrode (GCE) exhibits excellent electrocatalytic activity toward the oxidation of DA. The sensor displays a good linear response over the concentration range from 10 nM to 200 µM, with an ultrahigh sensitivity of 80 µA·µM⁻¹ cm⁻² and a low detection limit of 0.14 µM (S/N = 3). Owing to the synergistic electronic effect between Pd and Mo, the high density of exposed active sites, and the unique strained lattice structure of the bimetallene, the sensor enables accurate determination of DA concentrations even in the presence of interfering species such as AA and UA. In summary, the successfully fabricated PdMo bimetallene-based sensor offers the advantages of low cost, facile synthesis, a wide linear range, and high sensitivity, positioning it as a promising candidate for neurotransmitter detection applications. Full article

Jasmonates (JAs) are a diverse group of jasmonic acid (JA)-linked metabolites, including the biosynthetic intermediate 12-oxophytodienoic acid (OPDA). Although changes in JAs have been associated with plant responses to abiotic stress, the involvement and kinetics of specific forms such as JA, JA-Ile and OPDA require further clarification. This study analyzed jasmonate profiles in roots and leaves of two oat genotypes differing in drought tolerance. Jasmonates were quantified using UPLC-MS/MS, expression of key biosynthetic genes was assessed by qRT-PCR, and JA/OPDA treatments were applied to evaluate their effects on physiological and morphological responses to drought. Drought induced contrasting jasmonate dynamics in roots and leaves, with overall JA levels increasing in leaves and decreasing in roots, with genotype- and compound-specific differences. JA and JA-Ile ((+)-7-iso-jasmonoyl-L-isoleucine) showed similar trends, whereas OPDA displayed a distinct pattern. The tolerant genotype exhibited an early and marked reduction in root OPDA, while the susceptible one showed minimal change. Exogenous OPDA increased drought symptoms, reduced leaf relative water content and strongly decreased root length by limiting the formation of new thin roots. In contrast, JA application alleviated drought symptoms, reflected in a lower area under the drought progress curve, without affecting root length. Results suggest that under water deficit, reduced OPDA, likely due to its conversion into JA and JA-Ile, is associated with the development of small-diameter roots essential for maintaining water status in oat. Together, these results highlight tissue-specific differences in jasmonate dynamics during drought and show that OPDA and JA treatments lead to distinct drought-related responses in both leaves and roots. Full article

Ulcerative colitis (UC) is a chronic inflammatory disorder of the colon characterized by dysregulated mucosal immunity and progressive epithelial injury. Upadacitinib (UPA), a selective Janus kinase 1 (JAK1) inhibitor, has demonstrated clinical efficacy in UC, but its therapeutic application is often constrained by adverse effects arising from systemic drug exposure. This underscores the need for advanced, site-specific delivery systems that enhance local efficacy while minimizing systemic toxicity. Here, we developed a colon-targeted natural lipid nanoparticle formulation of UPA (UPA-nLNP) to improve therapeutic performance and safety. UPA-nLNP was prepared by thin-film hydration using digalactosyldiacylglycerol (DGDG), monogalactosyldiacylglycerol (MGDG), and phosphatidic acid (PA), mimicking the lipid composition of ginger-derived exosomal particles, and was characterized for particle size, surface charge, and encapsulation efficiency. The formulation exhibited excellent mucus-penetrating capability and was evaluated in a dextran sulfate sodium (DSS)-induced acute colitis model in C57BL/6 mice following oral administration (5 mg/kg). Pharmacokinetic analysis demonstrated increased colonic accumulation with reduced systemic exposure compared to free UPA. Treatment with UPA-nLNP improved body weight recovery, reduced disease biomarkers, and suppressed key proinflammatory cytokines in the colon, with no evidence of systemic toxicity. This innovative strategy holds strong potential to enhance the clinical utility of JAK1 inhibitors by providing a safer and more effective therapeutic approach for ulcerative colitis. Full article

Driven by the demand for miniaturization, high capacitance, and enhanced reliability in high-performance multilayer ceramic capacitors (MLCCs), the continuous thinning of inner electrode layers imposes increasingly stringent requirements on the size, distribution, morphology, and dispersion of nano-nickel powders. We systematically investigate how functional additives regulate the nucleation, growth, and microstructural evolution of nano-nickel synthesized via hydrazine-driven liquid-phase reduction of nickel sulfate. The results demonstrate that the alkanolamine complexing agent (TAC) significantly refines the average particle size and morphology of the nano-nickel through coordination effects. Furthermore, inorganic sulfur salts (ISP), acting via surface adsorption to passivate growth sites and provide catalytic effects, enable a precise and continuous reduction in the average particle diameter from 330 nm down to 60 nm at a mere trace dosage of ~10⁻⁷ mol/L. Regarding dispersion optimization, highly dispersed face-centered cubic (FCC) nano-nickel was successfully prepared by introducing multidentate carboxylate (NNA). High-resolution transmission electron microscopy (HRTEM) was employed to unveil, for the first time, the crystallographic origin of the anomalous surface protrusions typically observed in conventional reaction systems. We confirmed that the family of $\left\{10\overline{1}0\right\}$ crystal planes within these regions, which exhibits interfacial angles of 58.7° and 58.3°, corresponds to a thermodynamically metastable hexagonal close-packed (HCP) nickel phase originating from atomic stacking faults induced by rapid growth kinetics. To address this microstructural defect, a thioether-based amino acid (TAA) was introduced. TAA effectively suppresses the anisotropic growth of the metastable HCP phase through the strong steric hindrance of its long side chains and its selective adsorption onto high-energy facets. Full article

This study investigates the fabrication, characterization, and computational analysis of a Ti6Al4V porous scaffold for bone tissue engineering (BTE). The main objective is to address the stress-shielding effect caused by the mismatch in the mechanical properties between the scaffold and surrounding bone. An octet-truss architecture was considered to design a highly porous scaffold (with 80.5% porosity) and fabricated using selective laser melting (SLM). The scaffold was then treated with post-processing chemical etching in oxalic acid to remove surface defects and tailor topography. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that etching effectively removed adhered unmelted powder particles and created a distinct micro-textured strut surface (with increased roughness) that is conducive to osseointegration. The etching process also uniformly thinned down the struts and resulted in 10% mass loss. A compression test gave the scaffold’s compliance-corrected elastic moduli of 4.54 ± 0.18 GPa (pre-etching) and 3.53 ± 0.06 GPa (post-etching). These values closely match with the stiffness of human trabecular bone reported in the literature. The experimental modulus results were validated with a finite element model that predicted 4.188 GPa, which agrees well with the experiment. Furthermore, computational fluid dynamic simulations evaluated a permeability of 8 × 10^–9 m², consistent with transport in bone-like structures. Full article

Polyamines, putrescine, spermidine and spermine, are essential polycationic metabolites present in all eukaryotic cells, where they regulate fundamental processes including nucleic acid stabilization, translation, and stress responses. Spermidine synthase (SPDS), a member of the aminopropyltransferase (APT) family, catalyzes the transfer of an aminopropyl group from decarboxylated S-adenosylmethionine (dc-SAM) to putrescine to form spermidine. Although genomic analyses predict the presence of SPDS homologs in multiple fungal species, polyamine biosynthesis has not been experimentally characterized in the multidrug-resistant fungal pathogen Candidozyma auris. Here, we report the biochemical and functional characterization of the C. auris spermidine synthase, CauSpe3. The CauSPE3 gene complemented a Saccharomyces cerevisiae spe3Δ mutant demonstrating conserved function in vivo. Recombinant CauSpe3 was expressed in Escherichia coli, purified and analyzed using the fluorescence-based DAB-APT assay, which uses 1,2-diacetylbenzene (DAB) for polyamine detection. CauSpe3 catalyzed efficient conversion of putrescine to spermidine in the presence of dc-SAM, with K_half values of 65.5 ± 7.11 µM for putrescine and 66.9 ± 2.09 µM for dc-SAM, and V_max values of 7.1 ± 0.57 and 7.9 ± 0.12 nmol·µg⁻¹·min⁻¹, respectively. A catalytic-site mutant and heat-inactivated enzyme showed no detectable activity, and product formation was confirmed by means of thin-layer chromatography and mass spectrometry. These findings establish CauSpe3 as a functional spermidine synthase. Full article

The development of effective fluorescent probes for the detection of acids and bases, both in solution and in the solid state, is of particular interest worldwide, due to the possibility of preventing hazardous consequences for human health and the environment. In the present work, the synthesis of a 1,8-naphthalimide derivative, designed as a “fluorophore-receptor₁-spacer-receptor₂” model, is considered. The compound contains two receptors for analytes in one molecule and can operate as a fluorescent probe via PET and ICT mechanisms. The photophysical behavior of the synthesized derivative in solution, on strip paper, and in thin film was investigated. It was found that the transition from acidic to alkaline medium in solution is associated with a change in color that is visible with the naked eye (yellow–orange-red–blue). The change in fluorescence, both in solution and spread on a supporting surface (strip paper and thin film), can be spectrophotometrically observed. The influence of various volatile acids on the sensing activity of the synthesized compound in solution and deposited on a solid support was investigated. It was found that with increasing acid strength, the fluorescence intensity increases. The strip paper and thin film obtained with the synthesized compound show reversible switching between the “off” and “on” states of fluorescence. The strip paper exhibited good cycling under acid–base vapor stimulation. The results obtained demonstrate the possibility of application of the synthesized compound as a colorimetric and fluorescent probe for determination of pH in solution, and detection of acids, bases, and their vapors in indoor and outdoor residential and industrial premises, as well as in the environment. Full article