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Search Results (168)

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20 pages, 10909 KiB  
Article
Preparation Optimization and Antioxidant Properties of the β-Glucan and Ferulic Acid/Quercetin Complex from Highland Barley (Hordeum vulgare var. nudum)
by Yuanhang Ren, Yanting Yang, Mi Jiang, Wentao Gu, Yanan Cao, Liang Zou and Lianxin Peng
Foods 2025, 14(15), 2712; https://doi.org/10.3390/foods14152712 - 1 Aug 2025
Viewed by 152
Abstract
Polysaccharides and phenols are commonly co-localized in various plant-derived foods, including highland barley (Hordeum vulgare L. var. nudum Hook. f.). The interactions between these compounds can influence multiple characteristics of food products, including their physicochemical properties and functional performance, such as bioavailability, [...] Read more.
Polysaccharides and phenols are commonly co-localized in various plant-derived foods, including highland barley (Hordeum vulgare L. var. nudum Hook. f.). The interactions between these compounds can influence multiple characteristics of food products, including their physicochemical properties and functional performance, such as bioavailability, stability, and digestibility, which may support promising application of the phenol and polysaccharide complex in health food industry. In this study, two complexes with potential existence in highland barley, such as β-glucan-ferulic acid (GF) and β-glucan-quercetin (GQ), were prepared using the equilibrium dialysis method in vitro. FTIR and SEM results showed that ferulic acid and quercetin formed complexes with β-glucan separately, with covalent and non-covalent bonds and a dense morphological structure. The pH value, reaction temperature, and concentration of phosphate buffer solution (PBS) were confirmed to have an impact on the formation and yield of the complex. Through the test of the response surface, it was found that the optimum conditions for GF and (GQ) preparations were a pH of 6.5 (6), a PBS buffer concentration of 0.08 mol/L (0.3 mol/L), and a temperature of 8 °C (20 °C). Through in vitro assays, GF and GQ were found to possess good antioxidant activity, with a greater scavenging effect of DPPH, ABTS, and hydroxyl radical than the individual phenolic acids and glucans, as well as their physical mixtures. Taking GF as an example, the DPPH radical scavenging capacity ranked as GF (71.74%) > ferulic acid (49.50%) > PGF (44.43%) > β-glucan (43.84%). Similar trends were observed for ABTS radical scavenging (GF: 54.56%; ferulic acid: 44.37%; PGF: 44.95%; β-glucan: 36.42%) and hydroxyl radical elimination (GF: 39.16%; ferulic acid: 33.06%; PGF: 35.51%; β-glucan: 35.47%). In conclusion, the convenient preparation method and excellent antioxidant effect of the phenol–polysaccharide complexes from highland barley provide new opportunities for industrial-scale production, development, and design of healthy food based on these complexes. Full article
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11 pages, 1707 KiB  
Article
Genetic Variant of the Canine FGF5 Gene for the Hair Length Trait in the Akita: Utility for Hair Coat Variations and Welfare in Conservation Breeding
by Shinichiro Maki, Md Shafiqul Islam, Norio Kansaku, Nanami Arakawa, Akira Yabuki, Tofazzal Md Rakib, Abdullah Al Faruq and Osamu Yamato
Genes 2025, 16(8), 927; https://doi.org/10.3390/genes16080927 (registering DOI) - 1 Aug 2025
Viewed by 200
Abstract
Background/Objectives: Variations in hair length are observed in many dog breeds, as determined by the canine FGF5 gene. Long-haired Akitas, which are disqualified under breeding standards of Akitas, are sometimes born to short-haired parents and may have been subjected to treatments compromising [...] Read more.
Background/Objectives: Variations in hair length are observed in many dog breeds, as determined by the canine FGF5 gene. Long-haired Akitas, which are disqualified under breeding standards of Akitas, are sometimes born to short-haired parents and may have been subjected to treatments compromising animal welfare. Here, we aimed to identify an FGF5 variant associated with hair coat variations in Akitas in Japan, and to assess how welfare of this breed can be improved by carefully planned breeding. Methods: DNA samples were obtained from 60 Akitas in 2021 (modern Akitas) and 73 Akitas in the 1970s and the 1980s (classic Akitas). Sanger sequencing was performed on all exons and exon–intron junctions of the FGF5 gene to determine the causative variant of long hair in Akitas. A real-time PCR assay was developed to genotype FGF5:c.578C>T in modern and classic Akitas. Using 54 dogs from modern Akitas, scores (1 to 10) of hair length were compared among the three genotypes (C/C, C/T, and T/T). Results: Sanger sequencing revealed that the canine FGF5:c.578C>T variant was associated with long hair in Akitas in Japan. Genotyping revealed that the frequency of the mutant T allele was 0.350 in modern Akitas, which was significantly higher (p < 0.001) than in classic Akitas (0.212). The three genotypes were not in Hardy–Weinberg equilibrium (HWE) in modern Akitas but were in HWE in classic Akitas. There were significant differences in hair length scores among the three genotypes (p < 0.001) and between the C/C and C/T genotypes (p < 0.005). There was no significant difference in the scores between male and female dogs. Conclusions: This study revealed that a causative variant that determines the long hair trait of Akitas in Japan was the FGF5:c.578C>T variant, which was inherited in an incompletely dominant manner. Akita dog breeders were more likely to select heterozygous C/T dogs based on the appearance of the hair coat for breeding dogs with an ideal fluffy hair coat. This might result in a high mutant T allele frequency and the production of undesired long-haired Akitas with T/T, which may create welfare problems. Genetic testing for this variant is necessary to improve welfare and conserve the Akita breed. Full article
(This article belongs to the Special Issue Genetics in Canines: From Evolution to Conservation)
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16 pages, 3132 KiB  
Article
Role of Renin–Angiotensin System and Macrophages in Breast Cancer Microenvironment
by Abir Abdullah Alamro, Moudhi Abdullah Almutlaq, Amani Ahmed Alghamdi, Atekah Hazzaa Alshammari, Eman Alshehri and Saba Abdi
Diseases 2025, 13(7), 216; https://doi.org/10.3390/diseases13070216 - 10 Jul 2025
Viewed by 320
Abstract
Background/Objectives: The renin–angiotensin system (RAS) is well-established as a moderator of cardiovascular equilibrium and blood pressure. Nevertheless, growing evidence indicates that angiotensin II (Ang II), the principal RAS effector peptide, together with additional constituents, is involved in various malignancies. Since the immune system [...] Read more.
Background/Objectives: The renin–angiotensin system (RAS) is well-established as a moderator of cardiovascular equilibrium and blood pressure. Nevertheless, growing evidence indicates that angiotensin II (Ang II), the principal RAS effector peptide, together with additional constituents, is involved in various malignancies. Since the immune system is an important aspect in tumor development, this study sought to investigate the role of Ang II in the crosstalk between tumor-associated macrophages (TAMs) and breast cancer cells in the tumor microenvironment (TME). Methods: We treated THP-1-like macrophages with 100 nM Ang II for 24 h. The culture media thus obtained was used as conditioned media and applied at 50% on MCF-7 and MDA-MB-231 breast cancer cell lines. The effects of the conditioned media on cancer cell lines were then investigated by various methods such as a cell proliferation assay, migration assay, polarization assay, and by the detection of apoptosis and reactive oxygen species (ROS) generation. Results: We demonstrated that in vitro Ang II promotes macrophage polarization toward proinflammatory M1-like macrophages and anti-inflammatory M2-like macrophages. Interestingly, Ang II, through macrophages, showed varied effects on different breast cancer cell lines, promoting tumor growth and progression in MCF-7 while inhibiting tumor growth and progression in MDA-MB-23. Conclusions: This study has provided clear evidence that Ang II in the TME modulates TAM polarization and secretions, leading to different effects based on the type of breast cancer. Full article
(This article belongs to the Section Oncology)
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17 pages, 1965 KiB  
Article
The Effect of the Antidepressant Citalopram on the Bioconcentration and Biomarker Response of Daphnia magna at Environmentally Relevant Concentrations
by Haohan Yang, Jiacheng Tan, Hanyu Jiang, Hao Xing, Jingnan Zhang, Dexin Kong, Zhuoyu Chen and Linghui Kong
Toxics 2025, 13(7), 532; https://doi.org/10.3390/toxics13070532 - 25 Jun 2025
Viewed by 363
Abstract
The widespread use and pseudo-persistent occurrence of the antidepressant citalopram (CIT) could pose a potential ecological risk in the aquatic environment. The message about the bioconcentration and sensitive biomarker identification of CIT at the environmentally relevant concentrations is limited. In this study, an [...] Read more.
The widespread use and pseudo-persistent occurrence of the antidepressant citalopram (CIT) could pose a potential ecological risk in the aquatic environment. The message about the bioconcentration and sensitive biomarker identification of CIT at the environmentally relevant concentrations is limited. In this study, an integral evaluation of the phenotypic and biochemical effects of CIT on Daphnia magna (D. magna) was conducted at 0.5 and 10 µg/L. The biomarker screening includes energy metabolism, phototactic behavior, feeding dysfunction, and antioxidant stress responses. The carbohydrate, lipid, and protein content was determined using the assay of anthrone with glucose as standard, thiophosphorate-Vaniline with cholesterol as standard, and Coomassie brilliant blue with serum albumin as standard, respectively. The results showed the bioconcentration equilibrium of CIT reached at the exposure duration of 48 h during the uptake process. At the exposure concentrations of 0.5 and 10 µg/L, the bioconcentration factor of CIT was 571.2 and 67.4 L/kg, respectively. Both protein and lipid content significantly increased at 0.5 µg/L with a 1.78-fold elevation in total energy. Comparatively, the lipid content showed a significant increase at 10 µg/L, while the available total energy rose by 1.25-fold relative to the control group. The phototactic behavior of D. magna exposed to 0.5 µg/L CIT was markedly reduced at 48 h relative to control. In contrast, a significant decrease in phototaxis was observed after 6 h and then a significant increase at 12 h with a continuously obvious decline at 10 µg/L. The filtration rates were increased by 32% compared to controls at 0.5 µg/L, while the stimulatory effects disappeared at 10 µg/L. With regarding to the antioxidant enzyme activities, CIT exposure significantly inhibited the catalase activity both at 0.5 and 10 µg/L, while the glutathione S-transferase activity was obviously induced at 0.5 µg/L and inhibited at 10 µg/L. The expression level of 18s gene was significantly decreased at 10 µg/L. Only the gst gene expression level was significantly increased at 0.5 µg/L, while the 18s and cat gene expression level was obviously inhibited and induced at 10 µg/L. Comprehensively, the responses of the phenotypic traits and energy metabolism of D. magna at various environmental concentrations were sensitive for CIT. This study provided basic data for the risk estimation of CIT in the real freshwater environment. Full article
(This article belongs to the Special Issue Oxidative Degradation and Toxicity of Environmental Pollutants)
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27 pages, 2807 KiB  
Article
Development and Optimization of Grape Skin Extract-Loaded Gelatin–Alginate Hydrogels: Assessment of Antioxidant and Antimicrobial Properties
by Jovana Bradic, Anica Petrovic, Aleksandar Kocovic, Vukasin Ugrinovic, Suzana Popovic, Andrija Ciric, Zoran Markovic and Edina Avdovic
Pharmaceutics 2025, 17(6), 790; https://doi.org/10.3390/pharmaceutics17060790 - 17 Jun 2025
Cited by 1 | Viewed by 603
Abstract
Background: In this study, we aimed to develop and optimize unique eco-friendly gelatin–alginate hydrogels enriched with sustainable grape skin extract for advanced wound healing applications. Methods: Following confirmation of the extract’s antioxidant activity, hydrogels were synthesized by varying gelatin content and CaCl2 [...] Read more.
Background: In this study, we aimed to develop and optimize unique eco-friendly gelatin–alginate hydrogels enriched with sustainable grape skin extract for advanced wound healing applications. Methods: Following confirmation of the extract’s antioxidant activity, hydrogels were synthesized by varying gelatin content and CaCl2 concentration to achieve desirable crosslinking density, mechanical properties, and extract release behavior. Physicochemical characterization of hydrogels included equilibrium swelling analysis, mechanical testing, FTIR analysis, and in vitro release of extract from hydrogel. Moreover, the biocompatibility of hydrogels enriched with extract was assessed via MTT assay, while antimicrobial activity was tested against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 10145, and Candida albicans ATCC 10231. The antioxidant capacity of the hydrogels was evaluated using DPPH, ABTS, and FRAP assays. Results: Our results showed that higher gelatin and CaCl2 concentrations produced denser crosslinked networks, leading to reduced swelling and increased stiffness. Additionally, the extract exhibited a biphasic release profile from hydrogels, featuring an initial rapid release followed by sustained release over 24 h. Conclusions: The hydrogels maintained high biocompatibility and demonstrated selective antimicrobial activity, particularly against Escherichia coli, and satisfactory antioxidant activity. Obtained multifunctional sustainable hydrogels enriched with grape skin extract represent promising agents for managing skin conditions associated with oxidative stress and bacterial infections. Full article
(This article belongs to the Section Drug Delivery and Controlled Release)
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21 pages, 1735 KiB  
Review
Immunomodulatory Potential and Biocompatibility of Chitosan–Hydroxyapatite Biocomposites for Tissue Engineering
by Davide Frumento and Ștefan Țălu
J. Compos. Sci. 2025, 9(6), 305; https://doi.org/10.3390/jcs9060305 - 17 Jun 2025
Cited by 2 | Viewed by 800
Abstract
Chitosan–hydroxyapatite (CS-HAp) biocomposites, combining the biocompatibility and bioactivity of chitosan with the osteoconductive properties of hydroxyapatite, are emerging as promising candidates for tissue engineering applications. These materials consistently exhibit excellent cytocompatibility, with cell viability rates greater than 95% in MTT and Neutral Red [...] Read more.
Chitosan–hydroxyapatite (CS-HAp) biocomposites, combining the biocompatibility and bioactivity of chitosan with the osteoconductive properties of hydroxyapatite, are emerging as promising candidates for tissue engineering applications. These materials consistently exhibit excellent cytocompatibility, with cell viability rates greater than 95% in MTT and Neutral Red Uptake assays, and minimal cytotoxicity, as demonstrated by low levels of cell death in DAPI and Trypan blue staining. More importantly, CS-HAp biocomposites modulate the immune environment by enhancing the expression of anti-inflammatory cytokines (IL-10 and IL-4) and the pro-inflammatory cytokine TGF-β, while avoiding significant increases in TNF-α, IL-6, or NF-κB expression in fibroblast cells exposed to HAC and HACF scaffolds. In an in vivo dermatitis model, these biocomposites reduced mast cell counts and plasma histamine levels and significantly decreased pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), JAK1/3, VEGF, and AnxA1 levels. Structurally, HACF scaffolds demonstrated larger average pore sizes (95 µm) compared to HAC scaffolds (74 µm), with porosities of 77.37 ± 2.4% and 65.26 ± 3.1%, respectively. These materials exhibited high swelling ability, equilibrium water content, and controlled degradation over a week in culture media. In addition to their immunomodulatory effects, CS-HAp composites promote essential cellular activities, such as attachment, proliferation, and differentiation, thereby supporting tissue integration and healing. Despite these promising findings, significant gaps remain in understanding the underlying mechanisms of immune modulation by CS-HAp biocomposites, and formulation-dependent variability raises concerns about reproducibility and clinical application. Therefore, a comprehensive review is essential to consolidate existing data, identify key knowledge gaps, and standardize the design of CS/HAp composites for broader clinical use, particularly in immunomodulatory and regenerative medicine contexts. Full article
(This article belongs to the Special Issue Sustainable Biocomposites, 3rd Edition)
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19 pages, 1586 KiB  
Article
Michael Acceptor Compounds as Hemoglobin Oxygen Affinity Modulators for Reversing Sickling of Red Blood Cells
by Khadijah A. Mohammad, Asala H. Naghi, Mohini S. Ghatge, Benita Balogun, Mariana Macias, Salma Roland, Albert Opare, Osheiza Abdulmalik, Martin K. Safo, Abdelsattar M. Omar and Moustafa E. El-Araby
Pharmaceuticals 2025, 18(6), 783; https://doi.org/10.3390/ph18060783 - 24 May 2025
Viewed by 637
Abstract
Background/Objectives: Sickle cell disease (SCD) is caused by a β-globin gene mutation (βGlu6Val) that produces sickle hemoglobin (HbS). When deoxygenated, HbS polymerizes, leading to red blood cell (RBC) sickling; therefore, hemoglobin is a central therapeutic target for SCD. Current strategies include increasing [...] Read more.
Background/Objectives: Sickle cell disease (SCD) is caused by a β-globin gene mutation (βGlu6Val) that produces sickle hemoglobin (HbS). When deoxygenated, HbS polymerizes, leading to red blood cell (RBC) sickling; therefore, hemoglobin is a central therapeutic target for SCD. Current strategies include increasing the levels of oxygenated HbS (which cannot polymerize) and/or directly destabilizing the deoxygenated HbS polymer. This study aimed to design and synthesize next-generation Michael acceptor antisickling hemoglobin modifiers (MMA-206, MMA-207, MMA-208, and MMA-209) and evaluate their antisickling efficacy. Methods: Four Michael acceptor compounds (MMA-206 to MMA-209) were synthesized and characterized. Their pharmacologic activities and modes of action were assessed in vitro using disulfide exchange reaction with normal hemoglobin, sickling inhibition assays with sickle red blood cells, and hemoglobin oxygen equilibrium curve analysis with normal and sickle red blood cells. Results: MMA-206 exhibited the strongest antisickling activity, outperforming previously studied Michael acceptor antisickling agents. All four MMA analogues bound to hemoglobin at βCys93, destabilizing the low-oxygen-affinity T-state and thereby preventing deoxygenation-induced HbS polymerization and RBC sickling. In addition, they appeared to directly destabilize the HbS polymer, indicating a second mechanism of action. Furthermore, time-dependent oxygen equilibrium measurements confirmed that their pharmacologic effect was sustained over time in vitro. Conclusions: The new Michael acceptor compounds, particularly MMA-206, demonstrated potent antisickling effects via dual mechanisms and showed sustained activity. These findings highlight Michael acceptor compounds’ promise as hemoglobin oxygen-affinity modulators for the treatment of SCD. Full article
(This article belongs to the Section Medicinal Chemistry)
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14 pages, 1034 KiB  
Article
Prevalence of Genetic Variants Associated with Atrial Fibrillation Risk in the Asymptomatic Young Adult Population
by Manoranjani Murugan, Sambandam Ravikumar, Irisappan Ganesh, Yogesh Vetriselvan, Arunagiri Priyadharshini and Vishnu Bhat Ballambattu
Medicina 2025, 61(5), 900; https://doi.org/10.3390/medicina61050900 - 15 May 2025
Viewed by 540
Abstract
Background and Objectives: Atrial fibrillation (AF) is the most common cardiac arrhythmia globally, leading to a high risk of stroke and heart failure. Genetic factors are known to play an essential role in AF risk. However, studies on genetic predisposition in asymptomatic [...] Read more.
Background and Objectives: Atrial fibrillation (AF) is the most common cardiac arrhythmia globally, leading to a high risk of stroke and heart failure. Genetic factors are known to play an essential role in AF risk. However, studies on genetic predisposition in asymptomatic young populations remain limited. This study aimed to investigate the prevalence of genetic variants in the PITX2 (rs2200733, rs10033464, and rs13143308), TBX5 (rs883079), PRRX1 (rs3903239), ZFHX3 (rs2106261), and HAND2 (rs7698692) polymorphisms and to assess their correlation with susceptibility to AF in a young adult population in India. Materials and Methods: This cross-sectional study included 250 subjects aged 18–29. Detailed lifestyle and family histories were collected for each participant. Genetic variation was determined using a specific TaqMan SNP genotyping assay. Hardy–Weinberg equilibrium (HWE) analysis and chi-square tests were employed to assess genotype frequencies, and statistical associations with lifestyle factors (body mass index, alcohol consumption, and smoking) were evaluated using t-tests and descriptive statistics. Results: Minor allele frequencies were varied across the study population, with notable frequencies in rs2200733 T (16%), rs10033464 T (27%), rs13143308 T (32%), rs883079 T (46%), rs3903239 G (25%), rs2106261 T (26%), and rs7698692 G (14%). HWE analysis confirmed that all SNPs were in equilibrium (p > 0.05). Approximately 15% of individuals carried six or more risk alleles, indicating a significant genetic predisposition to AF despite the absence of clinical symptoms. Conclusions: This study provides new insights into the genetic predisposition to AF among young adults in India. The high prevalence of risk alleles in asymptomatic young adults highlights the necessity of early genetic screening for AF risk and the role of genetic counseling in preventing cardiac complications. Full article
(This article belongs to the Section Genetics and Molecular Medicine)
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23 pages, 18738 KiB  
Article
Interaction Between Glucagon-like Peptide 1 and Its Analogs with Amyloid-β Peptide Affects Its Fibrillation and Cytotoxicity
by Ekaterina A. Litus, Marina P. Shevelyova, Alisa A. Vologzhannikova, Evgenia I. Deryusheva, Alina V. Chaplygina, Victoria A. Rastrygina, Andrey V. Machulin, Valeria D. Alikova, Aliya A. Nazipova, Maria E. Permyakova, Victor V. Dotsenko, Sergei E. Permyakov and Ekaterina L. Nemashkalova
Int. J. Mol. Sci. 2025, 26(9), 4095; https://doi.org/10.3390/ijms26094095 - 25 Apr 2025
Viewed by 976
Abstract
Clinical data as well as animal and cell studies indicate that certain antidiabetic drugs, including glucagon-like peptide 1 receptor agonists (GLP-1RAs), exert therapeutic effects in Alzheimer’s disease (AD) by modulating amyloid-β peptide (Aβ) metabolism. Meanwhile, the direct interactions between GLP-1RAs and Aβ and [...] Read more.
Clinical data as well as animal and cell studies indicate that certain antidiabetic drugs, including glucagon-like peptide 1 receptor agonists (GLP-1RAs), exert therapeutic effects in Alzheimer’s disease (AD) by modulating amyloid-β peptide (Aβ) metabolism. Meanwhile, the direct interactions between GLP-1RAs and Aβ and their functional consequences remain unexplored. In this study, the interactions between monomeric Aβ40/Aβ42 of GLP-1(7-37) and its several analogs (semaglutide (Sema), liraglutide (Lira), exenatide (Exen)) were studied using biolayer interferometry and surface plasmon resonance spectroscopy. The quaternary structure of GLP-1RAs was investigated using dynamic light scattering. The effects of GLP-1RAs on Aβ fibrillation were assessed using the thioflavin T assay and electron microscopy. The impact of GLP-1RAs on Aβ cytotoxicity was evaluated via the MTT assay. Monomeric Aβ40 and Aβ42 directly bind to GLP-1(7-37), Sema, Lira, and Exen, with the highest affinity for Lira (the lowest estimates of equilibrium dissociation constants were 42–60 nM). GLP-1RAs are prone to oligomerization, which may affect their binding to Aβ. GLP-1(7-37) and Exen inhibit Aβ40 fibrillation, whereas Sema promotes it. GLP-1 analogs decrease Aβ cytotoxicity toward SH-SY5Y cells, while GLP-1(7-37) enhances Aβ40 cytotoxicity without affecting the cytotoxic effect of Aβ42. Overall, GLP-1RAs interact with Aβ and differentially modulate its fibrillation and cytotoxicity, suggesting the need for further studies of our observed effects in vivo. Full article
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10 pages, 3402 KiB  
Article
The Photophysical Properties of the Protonation States of SYPRO® Orange in Aqueous Solution
by Claire E. Baxter, Ali N. Khan, Christina M. Starcevic, Natalie Shkolnik and Jörg Zimmermann
Molecules 2025, 30(8), 1691; https://doi.org/10.3390/molecules30081691 - 10 Apr 2025
Cited by 1 | Viewed by 471
Abstract
SYPRO® Orange (SyO) is a zwitterionic dye that is used for protein gel staining, for thermal melt assays of proteins, and as a marker for misfolded proteins. However, while widely utilized, much of SyOs’ photophysics remains unexplored. We studied the effect of [...] Read more.
SYPRO® Orange (SyO) is a zwitterionic dye that is used for protein gel staining, for thermal melt assays of proteins, and as a marker for misfolded proteins. However, while widely utilized, much of SyOs’ photophysics remains unexplored. We studied the effect of pH on the photophysical properties of SyO in aqueous solution and found two well-defined transitions in the 0 to 10 pH range between three SyO species with distinct absorption and fluorescence properties. The first transition occurs around pH 1.5 and appears to be a coupled deprotonation–aggregation event. The second transition occurs between pH 4 and 5, and its pKa depends on the concentration of SyO. A link between the concentration dependence of the pKa of the second pH transition and the aggregation behavior of SyO at neutral pH is discussed, and aggregation equilibrium titrations are presented that suggest that SyO forms multimeric aggregates at neutral pH containing ten or more SyO molecules. Full article
(This article belongs to the Section Physical Chemistry)
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8 pages, 1427 KiB  
Proceeding Paper
Utilizing Spent Yeast for Tannin Adsorption in Chestnut Shell Treatment Solutions
by Elsa F. Vieira, Tomás Amaral, Ricardo Ferraz and Cristina Delerue-Matos
Eng. Proc. 2025, 87(1), 21; https://doi.org/10.3390/engproc2025087021 - 19 Mar 2025
Viewed by 265
Abstract
This study evaluated the use of brewer’s spent yeast (BSY) as an adsorbent for tannins from a chestnut shell extract (CS tannin extract). This extract was derived from an alkaline treatment (5% NaOH (v/v)) to recover cellulosic material from [...] Read more.
This study evaluated the use of brewer’s spent yeast (BSY) as an adsorbent for tannins from a chestnut shell extract (CS tannin extract). This extract was derived from an alkaline treatment (5% NaOH (v/v)) to recover cellulosic material from chestnut shells and needed valorization. Various BSY treatments, including lyophilization, immobilization in calcium alginate beads, and alkaline and acid treatments, were tested to identify which had the best tannin adsorption capacity. The results highlight BSY’s potential as a system to valorize tannins from this treatment solution. Full article
(This article belongs to the Proceedings of The 5th International Electronic Conference on Applied Sciences)
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19 pages, 8357 KiB  
Article
Binding of Pro-Inflammatory Proteins S100A8 or S100A9 to Amyloid-β Peptide Suppresses Its Fibrillation
by Ekaterina A. Litus, Marina P. Shevelyova, Alisa A. Vologzhannikova, Evgenia I. Deryusheva, Andrey V. Machulin, Ekaterina L. Nemashkalova, Maria E. Permyakova, Andrey S. Sokolov, Valeria D. Alikova, Vladimir N. Uversky and Sergei E. Permyakov
Biomolecules 2025, 15(3), 431; https://doi.org/10.3390/biom15030431 - 17 Mar 2025
Cited by 1 | Viewed by 1030
Abstract
Human serum albumin (HSA) is a natural depot of amyloid-β peptide (Aβ), a key player in Alzheimer’s disease (AD). HSA and pro-inflammatory Ca2+-binding proteins S100A8 and S100A9 are involved in Aβ metabolism and its deposition in the brain, serving as probable [...] Read more.
Human serum albumin (HSA) is a natural depot of amyloid-β peptide (Aβ), a key player in Alzheimer’s disease (AD). HSA and pro-inflammatory Ca2+-binding proteins S100A8 and S100A9 are involved in Aβ metabolism and its deposition in the brain, serving as probable triggers and therapeutic targets in AD, but their interplay with regard to Aβ binding/fibrillation is unclear. To this end, here we explore the in vitro binding of Ca2+-bound S100A8 or S100A9 to monomeric Aβ and the influence of the S100 proteins on Aβ fibrillation. The equilibrium dissociation constants of the complexes of dimeric S100A8/S100A9 with Aβ40/42 estimated by biolayer interferometry are 1–5 µM. S100A8 and S100A9 interfere with HSA binding to Aβ. Thioflavin T assay and electron microscopy data show that micromolar S100A8/S100A9 inhibit Aβ40 fibrillation, and the inhibitory effect of S100A8 exceeds that for HSA. The competition for Aβ between HSA and S100A8/S100A9 may contribute to the Aβ-HSA imbalance in the pro-inflammatory conditions in AD. Full article
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13 pages, 570 KiB  
Article
Search for Disease-Specific Genetic Markers Originated from the Vitamin D Binding Protein Gene Polymorphisms in the Multiple Sclerosis Cohort in the Latvian Population
by Jolanta Kalnina, Ilva Trapina, Samanta Plavina, Elina Leonova, Jegors Paramonovs, Nikolajs Sjakste and Natalia Paramonova
Int. J. Mol. Sci. 2025, 26(6), 2555; https://doi.org/10.3390/ijms26062555 - 12 Mar 2025
Cited by 1 | Viewed by 692
Abstract
Vitamin D is crucial for immune regulation, and its deficiency is linked to multiple sclerosis (MS). The GC gene encodes Vitamin D Binding Protein (VDBP), which regulates vitamin D transport and bioavailability. This study examines the association of GC polymorphisms (rs7041, rs4588) with [...] Read more.
Vitamin D is crucial for immune regulation, and its deficiency is linked to multiple sclerosis (MS). The GC gene encodes Vitamin D Binding Protein (VDBP), which regulates vitamin D transport and bioavailability. This study examines the association of GC polymorphisms (rs7041, rs4588) with MS susceptibility and their impact on 25-hydroxyvitamin D [25(OH)D] levels in a Latvian cohort. This case–control study included 296 MS patients and 253 healthy controls. Genotyping of rs7041 and rs4588 was conducted using restriction fragment length polymorphism analysis and validated by Sanger sequencing. Plasma 25(OH)D levels were measured in 131 MS patients using an enzyme-linked immunosorbent assay. Statistical analysis included Hardy–Weinberg equilibrium testing, Fisher’s exact test, allelic and genotypic frequency comparisons to assess MS risk, and the Kruskal–Wallis test for 25(OH)D level differences among genotypes. Our findings indicate that the rare rs7041-T and rs4588-A alleles, along with their corresponding haplotypes, exhibit a protective effect against MS (p < 0.001; OR = 0.65 for rs4588-A; p < 0.01; OR = 0.70 for rs7041-T). Conversely, the common rs7041-G and rs4588-C alleles were associated with an increased MS risk (p < 0.05). Individuals with the Gc1F/1F isotype had the highest average 25(OH)D levels (29.31 ng/mL), while Gc1S/2 carriers had the lowest (21.53 ng/mL). Our results indicate that GC polymorphisms may influence the susceptibility of Latvians to MS and vitamin D status. Full article
(This article belongs to the Special Issue The Role of Vitamin D in Human Health and Diseases 4.0)
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14 pages, 1814 KiB  
Article
Analysis of Phosphorus Soil Sorption Data: Improved Results from Global Least-Squares Fitting
by Joel Tellinghuisen, Paul Holford and Paul J. Milham
Soil Syst. 2025, 9(1), 22; https://doi.org/10.3390/soilsystems9010022 - 4 Mar 2025
Cited by 1 | Viewed by 641
Abstract
Phosphate sorption data are often analyzed by least-squares fitting to the two- or three-parameter Freundlich model. The standard methods are flawed by (1) treating the measured pseudo-equilibrium concentration C as the independent (hence error-free) variable and (2) neglecting the weighting that should accommodate [...] Read more.
Phosphate sorption data are often analyzed by least-squares fitting to the two- or three-parameter Freundlich model. The standard methods are flawed by (1) treating the measured pseudo-equilibrium concentration C as the independent (hence error-free) variable and (2) neglecting the weighting that should accommodate the varying precision of the data. Here, we address both of these shortfalls and use a global fit model to achieve optimal precision in fitting data for five acidic Australian soil types. Each individual dataset consists of measured C values for up to nine phosphate spiking levels C0. For each soil type, there are three–five such datasets from varying levels of phosphate fertilizer pre-exposure (Pf) two years earlier. These datasets are fitted simultaneously by expressing the Freundlich capacity factor a and exponent b as theoretically predicted functions of the assay amounts of Fe, Al, and P measured for each Pf. The analysis allows for uncertainty in both C and C0, with inverse-variance weighting from variance functions estimated by residuals analysis. The estimated presorbed P amounts Q depend linearly on Pf, with positive intercepts at Pf = 0, indicating residual phosphate in the soils prior to the laboratory phosphate treatments. The key takeaway points are as follows: (1) global analysis yields optimal estimates and improved precision for the fit parameters; (2) allowing for uncertainty in C is essential when the data include C values near 0; (3) varying data precision requires weighting to yield optimal parameter estimates and reliable uncertainties. Full article
(This article belongs to the Special Issue Adsorption Processes in Soils and Sediments)
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15 pages, 3421 KiB  
Article
Ligand-Independent Spontaneous Activation of Purinergic P2Y6 Receptor Under Cell Culture Soft Substrate
by Akiyuki Nishimura, Kazuhiro Nishiyama, Tomoya Ito, Xinya Mi, Yuri Kato, Asuka Inoue, Junken Aoki and Motohiro Nishida
Cells 2025, 14(3), 216; https://doi.org/10.3390/cells14030216 - 3 Feb 2025
Viewed by 1157
Abstract
G protein-coupled receptors (GPCRs) exist in the conformational equilibrium between inactive state and active state, where the proportion of active state in the absence of a ligand determines the basal activity of GPCRs. Although many GPCRs have different basal activity, it is still [...] Read more.
G protein-coupled receptors (GPCRs) exist in the conformational equilibrium between inactive state and active state, where the proportion of active state in the absence of a ligand determines the basal activity of GPCRs. Although many GPCRs have different basal activity, it is still unclear whether physiological stresses such as substrate stiffness affect the basal activity of GPCRs. In this study, we identified that purinergic P2Y6 receptor (P2Y6R) induced spontaneous Ca2+ oscillation without a nucleotide ligand when cells were cultured in a silicon chamber. This P2Y6R-dependent Ca2+ oscillation was absent in cells cultured in glass dishes. Coating substrates, including collagen, laminin, and fibronectin, did not affect the P2Y6R spontaneous activity. Mutation of the extracellular Arg-Gly-Asp (RGD) motif of P2Y6R inhibited spontaneous activity. Additionally, extracellular Ca2+ was required for P2Y6R-dependent spontaneous Ca2+ oscillation. The GPCR screening assay identified cells expressing 10 GPCRs, including purinergic P2Y1R, P2Y2R, and P2Y6R, that exhibited spontaneous Ca2+ oscillation under cell culture soft substrate. Our results suggest that stiffness of the cell adhesion surface modulates spontaneous activities of several GPCRs, including P2Y6R, through a ligand-independent mechanism. Full article
(This article belongs to the Section Cell Signaling)
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