Search Results (166)

The comparison of rice albumin (RA) after heat treatment at neutral and acidic conditions was investigated in this study. Compared to the decreased thioflavin T (ThT) intensity of RA at pH 2 during heating, the ThT intensity of RA at pH 7 increased throughout the process of fibrillization. After fibrillization, the ThT intensity of RA at pH 7 was significantly increased by 27%, 38% and 35% at the protein concentrations of 1%, 2% and 4%, respectively. In addition, worm-like fibrils with a contour length of 100–300 nm were formed after heating at neutral conditions, accompanied by an increased average particle size and structural re-arrangement. Furthermore, the fibril formation at pH 7 involved the enhancement of an ordered β-sheet structure. However, only spherical agglomerate with a larger average particle size (>2000 nm) was observed when RA was heated at pH 2, because excessive hydrolysis destroyed the fibril-core sequences of RA. Additionally, the low solubility and high hydrophobicity of RA at pH 2 were not conducive to the formation of fibrils. In a word, a neutral environment is suitable for RA-based fibril formation, which provides a new insight for its future uses in food products. Full article

The potentially tetradentate SNNS ligand N,N′-(ethane-1,2-diyl)bis(N″-(diethylcarbamothioyl)benzimidamide, H₂L, was synthesized by the reaction of ethylenediamine with two equivalents of the corresponding benzimide chloride. H₂L readily reacts with [AuCl(tht)] (tht = tetrahydrothiophene) under formation of the binuclear gold(I) complex [(AuCl)₂(H₂L-κS,S′)] (1) using its thiocarbonyl units as donors, while the nitrogen atoms remain uncoordinated, and no deprotonation was observed. The gold atoms establish almost linear Cl–Au–S bonds. The terminal Cl⁻ ligands can be replaced with thiocyanate units, giving [Au(SCN-κS)}₂((H₂L-κS,S′)] (2). The use of [Au(PPh₃)Cl] as a starting material gives the cation [{Au(PPh₃)}₂(H₂L-κS,S′)]²⁺ (3), which can be isolated as its PF₆⁻ salt. The products are air-stable compounds, which have been isolated in crystalline form and studied by X-ray diffraction and spectroscopic methods (IR, NMR, and MS). Full article

The Peste des Petits Ruminants (PPR) live attenuated vaccines, the PPR virus (PPRV) Nigeria 75/1 strain (lineage II) and PPRV India Sungry 96 strain (lineage IV), currently used for control and eradication programme are very efficient vaccines as they provide the host, sheep and goats, a lifelong immunity after a single minimum recommended dose of 10^2.5 TCID₅₀/mL. Unfortunately, both live attenuated vaccines are thermolabile and their use requires maintaining the cold chain from the manufactory premises to the field as most PPR-infected regions are facing of hot climate, with poor infrastructure, and the maintenance of an effective cold chain remains a challenge. To address this challenge, efforts have focused on developing thermotolerant (ThT) PPR vaccines using different stabilisers and improving the freeze-drying process. This study aimed to define the criteria for the evaluation of the stability of ThT PPR vaccines. A total of 37 batches of freeze-dried PPR vaccines using the PPRV Nigeria 75/1 strain, including eight (8) and twenty-nine (29) vaccines labelled as ThT and conventional formulations, respectively, were tested to evaluate the stability at temperatures of 40 °C to simulate the field conditions in some hot climate regions. All the vaccine batches included in this study initially showed acceptable levels of residual moisture, below 3%, and titres above the minimum WOAH standard requirement of 10^2.5 TCID₅₀/mL. Following the incubation at 40 °C, 56.7% and 46% of the 37 vaccine batches tested retained titres above 10^2.5 TCID₅₀/mL on day 3 and day 5, respectively. These vaccines use stabilisers such as skimmed milk, lactalbumin–sucrose, trehalose and one unnamed product (which may be protected for patent). The mean of titre loss among the PPR vaccines maintaining titres above 10^2.5 TCID₅₀/mL was 0.78 log10 at day 3 and 0.99 log10 at day 5, suggesting a significant early degradation during the first 3 days. Based on these data, it is proposed that thermotolerant PPR vaccines should maintain a minimum titre of 10^2.5 TCID₅₀/mL for vaccine dose on day 5 post-incubation at 40 °C with a titre loss below 1 log10 per mL. Preliminary immunogenicity test results showed that the PPR ThT vaccine meeting this criterion could be used in the field without maintaining a cold chain for up to 3 weeks, offering a practical solution for vaccination in remote areas. Full article

In our previous study, we observed that sodium chloride (NaCl) influences the formation of amyloid fibrils (AFs) by gluten in cooked wheat noodles. However, the underlying mechanisms of NaCl’s effect on AF formation during the cooking process remain unclear. This study systematically investigates the impact of NaCl concentration (0–2.0%, w/w) and cooking time (0–7 min) on AF formation. ThT fluorescence and Congo red confirmed AF formation across all NaCl concentration levels. At low NaCl concentrations, Na⁺/Cl⁻ shielding reduced electrostatic repulsion, enabling ordered β-sheet stacking, yielding long fibrils (1193 nm) with high β-sheet content (41.5%), dense cross-β structures, and elevated hydrophobicity (H₀ = 9980). Stable zeta potential and gradual particle growth (376 to 1193 nm) supported controlled elongation. Conversely, high NaCl concentrations disrupted hydrogen bonding, forming shorter fibrils (820 nm) with reduced β-sheets (28.9%) and lower hydrophobicity (H₀ = 5923). Rapid ThT kinetics (df/dt = 77,535 FU/min) and SE-HPLC profiles suggest that elevated concentrations of NaCl inhibit AF formation while inducing the generation of amorphous aggregates. These findings clarify the balance between ionic shielding and hydrophobic interactions in AF assembly, offering strategies to optimize noodle texture. Future studies should address the digestibility and health implications of salt-modulated AFs for functional food applications. Full article

Blending hydrogen with natural gas is emerging as a pivotal strategy in the transition to low-carbon energy systems. However, the exploitation of the natural gas infrastructure to distribute natural gas and hydrogen blends (and 100% hydrogen in the long-term) introduces several technical, economic, and safety issues. These latter are paramount, especially in urban distribution networks that supply residential buildings and dwellings, since the quality and safety of the living environment can also be significantly affected. In this scenario, the reliability of odorant concentration measurements according to the best practices currently in use for natural gas becomes crucial. This study is aimed at assessing the accuracy of odorant measurements at different concentration levels (i.e., low, medium, and high) in 100% methane, methane–hydrogen blend and 100% hydrogen. The obtained results show the tendency to overestimate the odorant concentration up to 2.3% in methane–hydrogen blends at medium and high concentrations of THT as well as the underestimation of −3.4% in 100% hydrogen at low concentration of TBM. These results are consistent with those of natural gas from the city distribution network with hydrogen content of 5% and 20%. Full article

The misfolding and aggregation of proteins into amyloidogenic assemblies are key features of several metabolic and neurodegenerative diseases. Human insulin has long been known to form amyloid fibrils under various conditions, which affects its bioavailability and function. Clinically, insulin aggregation at recurrent injection sites poses a challenge for diabetic patients who rely on insulin therapy. Furthermore, decreased responsiveness to insulin in type 2 diabetic (T2D) patients may lead to its overproduction and accumulation as aggregates. Earlier reports have reported that various factors such as pH, temperature, agitation, and the presence of lipids or other proteins influence insulin aggregation. Our present study aims to elucidate the effects of non–micellar anionic DMPG (1,2–dimyristoyl–sn–glycero–3–phosphoglycerol) lipids on insulin aggregation. Distinct pathways of insulin aggregation and intermediate formation were observed in the presence of DMPG using a ThT fluorescence assay. The formation of soluble intermediates alongside large insulin fibrils was observed in insulin incubated with DMPG via TEM, DLS, and NMR as opposed to insulin aggregates generated without lipids. ¹³C magic angle spinning solid–state NMR and FTIR experiments indicated that lipids do not alter the conformation of insulin fibrils but do alter the time scale of motion of aromatic and aliphatic side chains. Furthermore, the soluble intermediates were found to be more cytotoxic than fibrils generated with or without lipids. Overall, our study elucidates the importance of anionic lipids in dictating the pathways and intermediates associated with insulin aggregation. These findings could be useful in determining various approaches to avoid toxicity and enhance the effectiveness of insulin in therapeutic applications. Full article

The EGCG/PPN composite, prepared by combining pea protein nanofibrils (PPNs) with epigallocatechin gallate (EGCG), could be used as a multifunctional nanocarrier. Compared to pea protein isolate (PPI), EGCG/PPN composites exhibited remarkably higher turbidity and zeta potential, along with similar UV spectra. Intrinsic fluorescence spectroscopy, ThT fluorescence spectroscopy, and surface hydrophobicity analysis suggested that the interactions between EGCG and PPN were primarily driven by hydrophobic forces. UV spectra indicated that the microenvironment of amino acid residues in the tertiary structure of the protein changes upon complexation, and circular dichroism (CD) revealed that the incorporation of EGCG increases the β-sheet content in the protein’s secondary structure. Analyses of DPPH and ABTS radical scavenging activity, as well as reducing power, demonstrated that the synergistic effect between EGCG and PPN did not hinder the inherent antioxidant properties of EGCG but rather enhanced them significantly. Transmission electron microscopy (TEM) images showed that the addition of EGCG reconstructed the fibril morphology, thereby affecting the properties of PPNs. Overall, the composite fabricated through the interaction between PPN and EGCG shows great potential as a nanocarrier in the processing of functional foods. Full article

Objectives: The compound 3-(4-Hydroxy-3-methoxyphenyl) propionic acid (HMPA) is a terminal metabolite derived from polyphenol compounds. It has been studied for its potential to support brain health indirectly through its anti-oxidant effects and ability to enhance the gut environment; however, its role in dementia pathogenesis is unclear. Therefore, the aim of this study was to evaluate how HMPA inhibits Aβ42 aggregation in vitro. Methods: We examined the inhibitory effects of HMPA on amyloid-β protein (Aβ) aggregation using a thioflavin T (ThT) assay and electron microscopy (EM). Results: ThT assays demonstrated that HMPA inhibited both the nucleation and elongation phases of Aβ aggregation. Additionally, EM of low-molecular-weight (LMW) Aβ42 in the presence of HMPA demonstrated shorter fibrils compared to those formed without HMPA. The EC₅₀ of HMPA in LMW Aβ42 was 5–6 mM. Conclusions: These findings indicate that, similar to several polyphenol compounds such as myricetin and rosmarinic acid, HMPA may inhibit Aβ pathogenesis, although it requires a fairly high concentration in vitro. These findings suggest the potential of HMPA as a lead compound for modulating Aβ-related neurodegeneration. Full article

The Cerasus humilis, a perennial shrub belonging to the Cerasus genus, is native to China and holds significant ecological and economic importance. Growth regulation factors (GRF) are a family of transcription factors (TF) that play a key role in plant growth and development. This research entailed an in-depth examination of the GRF family in C. humilis, exploring its significance in the evolution of C. humilis. Twelve GRF genes were identified in the C. humilis genome. Named separately as ChGRF1-Chumilis15987.1, ChGRF2-Chumilis25207.1, ChGRF3-Chumilis26233.1, ChGRF4-Chumilis08578.3, ChGRF5-Chumilis18808.1, ChGRF6-Chumilis12052.1, ChGRF7-Chumilis10417.1, ChGRF8-Chumilis01608.1, ChGRF9-Chumilis14057.1, ChGRF10-Chumilis12169.1, ChGRF11-Chumilis14952.1, and ChGRF12-Chumilis07534.1. Phylogenetic analysis divided twelve GRF genes into five subfamilies. The gene structure, pattern, and cis-regulatory components of the GRF gene family were analyzed. In addition, according to collinearity analysis, there are six collinearity with Arabidopsis, twelve collinearity with Malus pumila, eight collinearity with Vitis vinifera, and three collinearity with Oryza sativa. Intraspecific collinearity analysis revealed the presence of three pairs of tandem repeat genes in the dwarf cherry genome. Identifying cis-acting elements revealed the prominent presence of gibberellin reaction elements, which are widely distributed in the promoter region. Cluster heatmap analysis showed that ChGRF2 had the highest expression levels in fruits and stems. ChGRF3 is highly expressed in red fruits of different colors, while ChGRF6 and ChGRF12 are highly expressed in yellow fruits. This study mainly focused on dwarf cherries treated with gibberellin. As the treatment time increased, the ChGRF gene showed different expression levels. ChGRF2, ChGRF3, ChGRF6, and ChGRF12 were up-regulated under gibberellin treatment. These genes all contain hormone-responsive cis-acting elements, indicating tht the ChGRF gene family plays a vital role under gibberellin treatment in C. humilis. The results laid the foundation for further research on the biological functions of the GRF genes in C. humilis. Full article

Alzheimer′s disease (AD) is a chronic neurodegenerative disorder that leads to memory loss and changes in mental and behavioral functions in elderly individuals. A major pathological feature of AD is the aggregation of amyloid-beta (Aβ) peptides, along with oxidative stress, inducing neurocellular apoptosis in the brain. Gobaishi (Galla chinensis), a traditional herbal medicine, has gained considerable attention for its constituents and potent therapeutic properties, particularly its strong inhibitory activity against Aβ fibril formation. In this study, we investigated the anti-Aβ aggregation effects of Gobaishi and its active constituents. We isolated two compounds by employing Thioflavin T (ThT) assay-guided fractionation, which were identified through various spectroscopic methods as pentagalloyl glucose (PGG) and methyl gallate (MG). Evaluation of their anti-Aβ aggregation effects revealed that PGG and MG contribute 1.5% and 0.7% of the activity of Gobaishi, respectively. In addition, PGG demonstrated significantly stronger DPPH radical scavenging activity (EC₅₀ = 1.16 µM) compared to MG (EC₅₀ = 6.44 µM). At a concentration of 30 µM, PGG significantly reduced the Aβ-induced cytotoxicity in SH-SY5Y cell lines compared to MG. Based on these findings, both Gobaishi and its active compound PGG are proposed as promising candidates for further investigation as potent anti-amyloidogenic agents in AD management. Full article

Background/Objectives: Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by excessive extracellular matrix (ECM) production and tissue stiffening, resulting in impaired lung function. Sodium hydrogen exchanger isoform 1 (NHE1) is a key mediator of intracellular and extracellular pH regulation, influencing fibroblast activation, motility, and proliferative pathways. This study investigates the role of NHE1 in actin stress fiber formation, fibroblast-to-myofibroblast differentiation, and cytokine secretion in IPF progression. Methods: Fibroblasts were treated with profibrotic agonists, including transforming growth factor-beta (TGFβ), lysophosphatidic acid (LPA), and serotonin (THT), in the presence or absence of the NHE1-specific inhibitor, EIPA. Actin stress fibers were visualized using phalloidin staining, while α-smooth muscle actin (α-SMA) expression and cytokine secretion (TGFβ, IL-6, and IL-8) were quantified using immunostaining and ELISA. Intracellular pH changes were measured using BCECF-AM fluorescence. Results: Profibrotic agonists induced significant actin stress fiber formation and α-SMA expression in fibroblasts, both of which were abolished by EIPA. NHE1 activity was shown to mediate intracellular alkalization, a critical factor for fibroblast activation. Cytokine secretion, including TGFβ, IL-6, and IL-8, was enhanced by agonist treatments but reduced with NHE1 inhibition. Chronic TGFβ exposure increased intracellular pH and sustained myofibroblast differentiation, which was partially reversed by EIPA. Conclusions: NHE1 is indicated to play a novel and potential role in processes supporting profibrotic agonists driving fibroblast activation and IPF progression. Targeting NHE1 could present a potential therapeutic approach to disrupt profibrotic pathways and mitigate IPF severity. Full article

CRISPR/Cas-based diagnostics offer unparalleled specificity, but their reliance on fluorescently labeled probes and complex nucleic acid extraction limits field applicability. To tackle this problem, we have developed a label-free, equipment-free platform integrating FTA card-based extraction, CRISPR/Cas12a, and pre-folded G-quadruplex (G4)–Thioflavin T (ThT) signal reporter. This system eliminates costly fluorescent labeling by leveraging G4-ThT structural binding for visible fluorescence output, while FTA cards streamline nucleic acid isolation without centrifugation. Achieving a limit of detection (LOD) to 10¹ CFU/mL for Escherichia coli O157:H7 in spiked food samples, the platform demonstrated 100% concordance with qPCR and standard fluorescent probe-based CRISPR/Cas12a system. Its simplicity, minimal equipment (portable heating/imaging), and cost-effectiveness make it a revolutionary tool for detecting foodborne pathogens in resource-limited environments. Full article

Herein, we proposed a versatile G-quadruplex (G4)-tetrahedral DNA framework (G4-TDF) nanostructure functionalized origami microfluidic paper-based device (μPADs) for fluorescence detection of K⁺ by lighting up thioflavin T (ThT). In this work, TDF provided robust structural support for G-rich sequence in well-defined orientation and spacing to ensure high recognition efficiency, enabling sensitive fluorescence sensing on origami μPAD. After introducing ThT, the G-rich sequences extended from TDF vertices formed a parallel G4 structure, showing weak fluorescence signal output. Upon the presence of target K⁺, this parallel G4 structure transitioned to antiparallel G4 structure, leading to a significantly increase in fluorescence signal of ThT. Benefiting from the outstanding fluorescence enhancement characteristic of the G4 structure for ThT and excellent specificity of the G4 structure to K⁺ plus satisfactory recognition efficiency with the aid of TDF, this origami paper-based fluorescence sensing strategy exhibited an impressive detection limit as low as 0.2 mM with a wide range of 0.5–5.5 mM. This innovative G4-TDF fluorescence sensing was applied for the first time on μPAD, providing a simple, effective, and rapid method for K⁺ detection in human serum with significant potential for clinical diagnostics. Full article

Background/Objectives: Amyloid-β (Aβ) plaque accumulation, oxidative stress, and cholinergic dysfunction are hallmarks of Alzheimer’s disease (AD), a neurodegenerative disability that progresses over time, ultimately resulting in the loss of neurons. The side effects and limitations of current synthetic drugs have shifted attention toward natural alternatives. This study investigates the ethanolic extract of Aegle marmelos (L.) Corrêa fruits for their antioxidant, AChE-inhibitory, and anti-amyloidogenic properties, as well as their neuroprotective effects against amyloid beta-peptide (Aβ_1–42). Methods: Phytochemical constituents were identified through HR-LCMS analysis and their antioxidant (DPPH, FRAP) and neuroprotective activities (AChE inhibition, ThT binding, MTT assay, ROS reduction, MMP restoration, and AD-related gene expression via qRT-PCR) were assessed using SHSY-5Y neuroblastoma cells. Results: The extract revealed the existence of flavonoids, phenols, and other bioactive substances. In vitro assays demonstrated strong antioxidant and AChE-inhibitory activities, while the ThT binding assay showed protection against amyloid-β aggregation. The extract exhibited no cytotoxicity in SHSY-5Y cells, even at a concentration of 500 μg/mL, whereas Aβ_1–42 at 20 μM induced significant cytotoxicity. Co-treatment with Aβ_1–42 (10 μM and 20 μM) and the extract improved cell viability (˃50%) and reduced ROS levels. Additionally, the extract restored mitochondrial membrane potential in Aβ_1–42 treated cells, highlighting its role in preserving mitochondrial function. Conclusions: These findings suggest that A. marmelos fruits serve as a powerful source of natural antioxidants, AChE inhibitors, and anti-amyloidogenic agents, positioning them as a compelling option for AD treatment. Full article

Agents that target the amyloid-β (Aβ) peptide associated with Alzheimer’s disease have seen renewed interest following the clinical success of antibody therapeutics. Small molecules, specifically metal-based complexes, are excellent candidates for advancement, given their relative ease of preparation and modular scaffold. Herein, several ruthenium–arene complexes containing 2,2-bipyridine (bpy) ligands were prepared and evaluated for their respective ability to modulate the aggregation of Aβ. This was carried out using the three sequential methods of thioflavin T (ThT) fluorescence, dynamic ligand scattering (DLS), and transmission electron microscopy (TEM). Overall, it was observed that RuBA, the complex with a 4,4-diamino-2,2-bipyridine ligand, had the greatest impact on Aβ aggregation. Further evaluation of the complexes was performed to determine their relative affinity for serum albumin and biocompatibility towards two neuronal cell lines. Ultimately, RuBA outperformed the other Ru complexes, where the structure–activity relationship codified the importance of the amino groups on the bpy for anti-Aβ activity. Full article