Search Results (12,292)

The development of biocompatible and mechanically flexible skeletal scaffolds is a significant challenge in modern regenerative medicine. In this study, we developed composite scaffolds based on biodegradable chitosan polymer and hydroxyapatite particles. We have shown for the first time that treatment with sodium hydroxide solution, which is often used to convert chitosan scaffolds into an insoluble form, can cause alkali sorption by hydroxyapatite particles. This has been demonstrated by our experiments. It has also been shown that the alkaline treatment of composite scaffolds increases the pH of the surrounding culture medium, reducing the viability of mesenchymal stromal cells by 60–70%. As an alternative to the processing of composite scaffolds using chitosan and hydroxyapatite, we propose heat treatment. This method allows us to produce stable scaffolds without affecting cell viability. Heat treatment promotes the formation of bonds between free amino groups in chitosan and phosphate groups in hydroxyapatite, as well as increasing the elasticity of the composite matrices in humid conditions. Full article

Salinization stress poses a major environmental factor that adversely affects maize (Zea mays L.) growth and development. Thus, identifying and utilizing alkaline tolerance-related genes in maize is crucial for enhancing resistance to alkaline stress. In this study, a genome-wide association study (GWAS) was conducted to analyze alkali tolerance in seedlings, focusing on biomass-related traits at the seedling stage across a panel of 212 maize inbred lines. The analysis found nine single-nucleotide polymorphism (SNP) loci significantly associated with alkali tolerance during the seedling stage. Within the confidence intervals of these loci, 57 genes with clear functional annotations were identified, among which eight were predicted to be involved in alkali tolerance based on functional annotation and homology analysis. qRT-PCR expression validation of selected candidate genes revealed that the relative expression level of GRMZM2G028089 was similar between in L99 and M-J244-3 lines. In contrast, the expression levels of GRMZM2G071196, GRMZM2G313162 and GRMZM5G883126 were higher in the L99 line compared to M-J244-3, suggesting their potential positive regulatory roles in the response to alkaline stress. These findings provide important theoretical support for the targeted breeding of alkali-resistant maize varieties. Full article

The Tawenchahanxi mining area, situated in the southeastern Qimantagh region of the East Kunlun Orogenic Belt, hosts a skarn-type Fe–polymetallic deposit associated with acidic granitic intrusions. Laser ablation–inductively coupled plasma–mass spectrometry zircon U–Pb dating yields ages of 233.3 ± 1.2 to 234.3 ± 1.1 Ma for a granodiorite and 397.7 ± 1.4 Ma for a quartz porphyry, indicating two magmatic intrusive events during the Early Devonian and Late Triassic. The Early Devonian quartz porphyry is characterized by high ${\mathrm{S}\mathrm{i}\mathrm{O}}_2$ (72.39%–74.04%), high total alkalis (7.81%–7.83%), high TFeO (>1.0%) and high crystallization temperatures (~865 °C), together with low CaO (1.64%–1.70%) and MgO (0.61–0.65%), which are all consistent with A-type granite affinity. The granodiorite exhibits aluminum saturation index (A/CNK) values of 0.67–1.07 (metaluminous to weakly peraluminous) and belongs to the high-K calc-alkaline series. It exhibits moderate negative Eu anomalies (δEu = 0.71–0.83), and zircon saturation temperatures of ~748 °C, collectively indicative of I-type granite affinity. Both rock suites display depletion in Nb, Ta, and Sr and enrichment in Rb and LREEs. Zircon Hf isotopic data show εHf(t) values of −0.64 to 0.57 for the quartz porphyry and −4.37 to −1.06 for the granodiorite, indicating derivation primarily from partial melting of ancient crust with variable mantle contributions. These intrusions formed during post-collisional extensional (Early Paleozoic) and collisional to post-collisional (Late Paleozoic–Early Mesozoic) stages, respectively, associated with mantle magma underplating and crust–mantle mixing. Such processes formed the material basis for the polymetallic mineralization in the Tawenchahanxi district by providing Fe–Cu–Pb–Zn and other ore-forming elements from deeper crust. Full article

Oxidative stress (OS) and sperm DNA fragmentation (SDF) are complementary contributors to male infertility. OS characterizes a compromised seminal redox status, whereas SDF quantifies downstream genomic damage. Human sperm are highly susceptible to redox damage due to lipid-rich membranes and disrupted post-meiotic DNA-repair capacity. Excess reactive oxygen species (ROS) can cause lipid peroxidation, oxidative base lesions, and DNA strand breaks that impair fertilization, embryo development, and pregnancy outcomes. This review explains how OS promotes genomic instability and summarizes the main laboratory assays that assess redox status and SDF in semen. These include direct ROS chemiluminescence assay, oxidation–reduction potential, total antioxidant capacity/ferric reducing antioxidant power, and lipid peroxidation biomarkers, alongside SDF platforms (Sperm Chromatin Structure Assay, terminal deoxynucleotidyl transferase dUTP nick-end labeling, alkaline/neutral Comet, and sperm chromatin dispersion). Additionally, guideline-aligned indications are highlighted to clarify the conditions for testing OS and SDF. OS testing is most relevant in men with leukocytospermia or suspected genital tract infection or inflammation, including dysbiosis; in cases of major modifiable exposures such as smoking or heat; and for early monitoring after treatment. SDF testing is particularly informative in couples with recurrent pregnancy loss and in unexplained infertility with normal semen parameters. Combined OS and SDF testing is recommended in clinical varicocele, repeated in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) failure, poor embryo development, and follow-up after targeted therapy. Management centers on treating infection and inflammation, improving lifestyle and environmental factors, considering varicocelectomy when indicated, using targeted antioxidant therapy in men with documented OS, and selectively applying sperm selection technologies or testicular sperm for ICSI when SDF remains high. Priorities include assay standardization, etiologic attribution of DNA damage, and trials testing OS/SDF-guided pathways with live birth as the primary endpoint. When used selectively and in the appropriate context, OS and SDF testing can help refine diagnosis, improve counseling, and help personalize care of infertile couples. Full article

Biochar, produced by pyrolyzing biomass under limited oxygen, can improve soil quality while supporting long-term carbon sequestration. This study compared two wheat-straw biochars (BC)made at 450 °C (BC1) and 600 °C (BC2), with a commercial hardwood biochar produced at 1280 °C (BC3) using lettuce in a sandy, nutrient-poor soil under a carbon capture, utilization, and storage (CCUS) perspective. Higher pyrolysis temperature increased fixed carbon, ash, and alkalinity and reduced volatile matter, indicating greater carbon stability (BC2 > BC1). Germination tests showed good compatibility, with BC1 performing best, likely because moderate temperatures retain more labile organic fractions. In growth-chamber trials (0.75% w/w), biochar boosted lettuce biomass and root development mainly when combined with mineral fertilization, with BC2 (25% and 59%, respectively) and BC3 (18% and 52%, respectively) yielding the strongest gains; unfertilized plants responded little, confirming that biochar is mainly a soil conditioner rather than a nutrient source. Biochar also stimulated soil enzymes linked to C, N, and P cycling and improved leaf chlorophyll, nitrogen status, and antioxidant capacity under fertilization. The nutrient profiles differed by biochar: BC1 increased K and nitrate, while BC2/BC3 lowered nitrate and BC3 enhanced Ca, Mg, and P uptake. Overall, agronomic outcomes depend on feedstock and pyrolysis temperature: mid-temperature biochars enhance productivity and soil biological activity, whereas high-temperature biochars maximize carbon permanence. Full article

To improve the extrusion processing of wood–plastic composites (WPCs), functional additives known as internal lubricants are incorporated into the composite formulations. The lubricants play a crucial role in decreasing the melt viscosity of WPCs, which in turn has a positive impact on energy consumption, productivity, and overall composite performance. This study shows the effect of suberinic acids (SAs), extracted from birch outer bark via alkaline water and water–ethanol hydrolysis at different pH values, on the processing behavior and properties of a recycled polypropylene-based composite filled with pine microfibers. The extracted SAs were characterized by gas chromatography–mass spectrometry, Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis, and differential scanning calorimetry. The conducted analyses revealed notable differences in the chemical composition, molecular weight, and molecular polydispersity of the SAs. Betulin was identified as the dominant component (49–86%). The pine sawdust was treated with 2% NaOH at 90 °C for 90 min prior to composite fabrication. The incorporation of 4.0 wt% SAs into the WPC formulations reduced the extruder rotor’s maximum and minimum torques torque, indicating improved processability of the composite. Mechanical and wetting properties of the WPC samples were evaluated. The samples containing SAs exhibited an increased elongation at break by 37.9–51.6% and bending deformation by 12.8–17.5%, depending on the extraction conditions of SAs, accompanied by a slight reduction in the mechanical properties and slight increase in water sorption compared with the composite filled with the alkaline-treated pine microfibers. The results showed enhanced flexibility and ductility in the SAs-containing WPCs. The presence of a 1.0 wt% maleic anhydride-grafted polypropylene in the samples led to an increase their mechanical properties, along with the reduced water sorption. Full article

Background: Despite extensive preclinical evidence that statins enhance osteogenesis and the widespread clinical use of platelet-rich fibrin (PRF), the clinical effectiveness of statin-incorporated PRF (SIM-PRF) in limiting peri-implant crestal bone loss remains insufficiently validated. Objectives: To address the mentioned gap, we integrated in vitro assays on human periodontal ligament stem cells (hPDLSCs) with a controlled clinical trial to test whether SIM-PRF reduces early and 12-month marginal bone loss versus PRF alone and PRF with bone graft. Methods: In vitro, cytotoxicity, migration and osteogenic differentiation were assessed, in addition to the effect on basal inflammatory markers. Clinically, 24 immediate-implant cases were randomized to receive PRF, PRF+SIM, or PRF+bone graft, with CBCT-based crestal bone change measured at 0–3, 3–6, and 6–12 months. Results: Flow cytometry confirmed the mesenchymal identity of the isolated hPDLSCs, which exhibited dose-dependent responses to SIM treatment. Lower SIM concentrations (0.1 μM) enhanced osteogenic differentiation, as evidenced by increased mineralization, alkaline phosphatase activity, and expression of osteogenic markers (RUNX2 and osteocalcin), while maintaining cell viability and migration. Both SIM concentrations (0.1 μM and 1 μM) significantly reduced basal pro-inflammatory cytokine expression (TNF-α and IL-6). Radiographic analysis revealed significantly reduced crestal bone loss (p < 0.001) in the PRF-SIM and PRF-Bone groups compared to PRF alone, particularly during early postoperative intervals (0–3 and 3–6 months). Notably, no significant difference was observed between the PRF-SIM and PRF-Bone groups (p > 0.05) in preserving the peri-implant bone. Conclusions: These findings highlight the potential of SIM-loaded PRF as an effective, biocompatible, and patient-friendly approach to enhance bone regeneration and implant success. Full article

(1) Background: Acidogenic Western-style diets disrupt gut bacteria promoting obesity-related diseases. Here, we investigated whether long-term feeding of alkalinized dietary casein as a protein source (ammonium hydroxide enhancement, AHE) modulates microbiome structure/functions under high-fat conditions, and normal diets, and whether these responses are sex-dimorphic. (2) Methods: C3H/HeJ mice (N = 256; equal sex distribution) received either control casein (CC), AHE casein (CCN), high-fat casein (HFC), or AHE high-fat casein (HFCN) diets from 6 to 18 months. Body mass and survival were tracked; fecal samples collected at 16 months were sequenced and underwent shotgun metagenomics. (3) Results: Diet and sex jointly shaped host metrics. AHE diets taxonomically showed an abundance of Verrucomicrobiota phyla predominating in most cohorts, notably Akkermansia muciniphila. Within Pseudomonadota, Christensenella was identified, along with other taxa associated with beneficial health outcomes, including Lactococcus lactis, Lactococcus cremoris, Pediococcus acidilactici, and families Lachnospiraceae/Oscillospiraceae. Additionally, sex- and diet-dependent advantageous enriched functions associated with AHE that enhanced electron transport, B-vitamin cofactor pathways, and mucosal/redox support were observed. (4) Conclusions: In the long term, pH-directed protein chemistry is a tractable lever for gut ecology during high-fat feeding, enriching and promoting the balance of beneficial taxa, providing a mechanistic bridge between dietary acid load and microbiome remodeling. Full article

The sustainable recycling of valuable metals from spent lithium-ion batteries (LIBs) is imperative for closing the resource loop. This study presents an integrated strategy for the stepwise recovery of metals from spent cathode sheets by in situ thermal reduction and selective leaching. The in situ thermal reduction converted the cathode material into a mixture of Li₂CO₃, LiAlO₂, Ni, Co, NiO, and CoO while simultaneously liberating the cathode materials from the Al current collector through binder removal. A combined process of water leaching, wet sieving, and filtration successfully achieved the separation and enrichment of Li-rich aqueous solution (near 60% Li), Al-rich coarse fraction (over 87% Al), and fine powder enriched with transition metals (over 90% of Ni, Co, and Mn). The pyrolysis gases released from binder decomposition were the key driver for forming Li₂CO₃, whereas the concurrent generation of LiF and LiAlO₂ limited direct water leaching efficiency. An alkaline leaching step was therefore introduced to co-extract Al and the associated Li from LiAlO₂, followed by an acid leaching step that recovered over 96% of the transition metals from the treated residue without external reductants. Complete mass balance analysis shows that the integrated process achieved overall recoveries of 91.86% for Li, 91.93% for Ni, 92.23% for Co, and 92.61% for Mn from all the combined leachate streams. Consequently, this work provides a reagent-saving, stepwise hydrometallurgical process for the comprehensive recycling of valuable metals from spent LIBs. Full article

This study investigated the α-glucosidase inhibitory potential of enzymatic/alkaline treatments from Palmaria palmata using different proteases and pairwise combinations thereof. Treatments prepared with Alcalase^®, Flavourzyme^®, and Formea^® Prime, alone or in combination, were evaluated for dose-dependent inhibitory activity. Alcalase^®-derived treatments exhibited the highest α-glucosidase inhibition, achieving an IC₅₀ of 2.48 mg·mL⁻¹, outperforming other treatments and combinations. Membrane fractionation of the Alcalase^®-derived treatment into >5 kDa, 3–5 kDa, 1–3 kDa, and <1 kDa fractions revealed a size-dependent trend, with the <1 kDa fraction showing the strongest inhibition (IC₅₀ of 1.94 mg·mL⁻¹). Three peptides, RADIPFRRA, DGIAEAWLG, and FWSQIFGVAF, from the <1 kDa fraction were identified as potential α-glucosidase inhibitors using the BIOPEP-UWM database and were further selected based on a Peptide Ranker score above 0.6 for in silico docking analyses. Docking revealed distinct binding modes: RADIPFRRA and DGIAEAWLG occupied the catalytic cleft, interacting with key residues (Asp518, Asp616, Trp481, Trp613) consistent with competitive inhibition, whereas FWSQIFGVAF bound to a peripheral site, suggesting potential allosteric modulation. Physicochemical analysis further highlighted differences in charge and isoelectric point correlating with their binding behavior. Together, these findings demonstrate that low-molecular-weight peptides derived from P. palmata proteins, particularly those generated by Alcalase^®, possess significant α-glucosidase inhibitory activity, and provide structural insights for the rational design of peptide-based modulators of carbohydrate metabolism. Full article

Potato is a vital crop in the United States, and increasing its production is essential. Due to their differences in rooting characteristics and nitrogen (N) needs, each potato cultivar generally receives specific research-based N recommendations. However, limited research exists on how other fertilizer nutrients, including micronutrients and plant growth-promoting rhizobacteria (PGPR), affect potato yield and quality. This study evaluated the response of Mesa Russet potatoes to various pre-plant and foliar fertilizer treatments on sandy, alkaline soil in Colorado, USA for two growing seasons. Six fertilizer treatments were tested in a randomized complete block design with four replications: (1) 4-13-17-1S (control), also known as the Farmer’s Standard, (2) 3-10-13, (3) 3-10-13 + PGPR, (4) 3-10-13-1S-1Zn, (5) 9-15-3-1S-0.25Zn + K-acetate foliar, and (6) 9-15-3-1S-0.25Zn + 0-0-15-5S foliar. The results showed that treatment PGPR maximized tuber bulking rate by 1.5 g plant⁻¹ day⁻¹, and 3.3 g plant⁻¹ day⁻¹ in 2016 and 2017, respectively, compared to the control treatment. Also, treatment 3-10-13 + PGPR had the highest total and larger tuber (>114 g, >170 g and >284 g) yields in both years. In contrast, the control (4-13-17-1S) had the lowest yield in both years. Treatment 9-15-3-1S-0.25Zn + K-Ac foliar resulted in total yields in both years that were statistically similar to the PGPR treatment; this treatment had the highest N, P, and Zn applications compared to all other treatments. Treatment 9-15-3-1S-0.25Zn + 0-0-15-5S foliar exhibited marketable yields (tubers > 114 g) comparable to the PGPR treatment in both years; this treatment had the highest S application as compared to the others. Further testing of PGPRs, S, and Zn individually and in combination is needed to evaluate their impact on other Russet potato cultivars grown in sandy soils prior to broadening these recommendations. Full article

Background: Well-known risk factors for soft tissue heterotopic ossification (HO) include aging and mechanical stress, which may be linked to oxidative stress and downstream nucleotide metabolites. Thus, we investigated the involvement of extracellular ATP (ex-ATP) and its metabolites in the oxidative stress-induced mineralization of TT-D6 cells and primary mouse tendon cells. Methods: An osteogenic culture with the intermittent addition of hydrogen peroxide was monitored for two weeks using metabolomic and gene expression analyses. Results: Calcium deposition was significantly enhanced by 0.3 mM hydrogen peroxide in the osteogenic media after 2 weeks, with minimal calcification in its absence. Similar results were observed in a medium transfer experiment using 3-day-old hydrogen peroxide-treated conditioned medium, which led to an increased expression of osterix and alkaline phosphatase. Metabolomic analysis revealed a gradual increase in ex-ATP and its metabolites, including ADP, AMP, and adenosine, in the medium. The metabolite increase was enhanced by hydrogen peroxide after 12 h. Moreover, exogenous adenosine (100 μM) increased mineralization in osteogenic media. Additionally, 1 μM dipyridamole, an inhibitor of equilibrative nucleoside transporter 1 (Ent1), also increased it in response to low-dose (0.1 mM) hydrogen peroxide. Conclusions: The enhanced osteogenic calcification of the tendon cell culture by hydrogen peroxide was associated with an increase in extracellular nucleotide metabolites, especially adenosine, with some evidence of causality. Full article

The present study evaluates the electrochemical behaviour of reinforcing steel embedded in an alkali-activated eco-cellular geopolymer concrete designed for applications in environments with high chloride exposure. The material was formulated using a ternary precursor composed of fluid catalytic cracking residue (FCC), Class F fly ash, and ground granulated blast furnace slag (BFS), activated with an alkaline solution and combined with preformed foam to generate a microstructure characterised by predominantly closed porosity and low capillary connectivity. The electrochemical response of the system was assessed through open circuit potential (OCP) measurements, Tafel polarisation curves, electrochemical impedance spectroscopy (EIS), and potentiodynamic tests under accelerated exposure to NaCl solutions. The results demonstrate a markedly improved electrochemical performance, evidenced by shifts in OCP towards more noble values, reductions of 45–65% in corrosion current density (Icorr), and increases of up to fourfold in charge transfer resistance (Rct), together with the development of broader and more stable passive regions. This behaviour is attributed to the synergistic interaction between the formation of dense N-(C)-A-S-H (sodium/calcium–aluminosilicate hydrate) and C-(A)-S-H (calcium–aluminosilicate hydrate) gels, the eco-cellular architecture with low capillary connectivity, and the stable high alkalinity of the activated matrix, which collectively restrict ionic transport and promote the passive stability of the reinforcing steel—defined here by noble OCP values, low Icorr, high Rct, and sustained passive domains in polarisation curves. Overall, the findings position the developed eco-cellular geopolymer concrete as a sustainable, high-performance alternative for infrastructure exposed to chloride-rich environments. Full article

Long-term tillage management fundamentally reshapes soil’s physical and chemical environment, yet an integrated, predictive characterization of the distinct chemical signatures induced by no-tillage (NT) versus chisel tillage (CT) remains limited. We analyzed an eight-year dataset (2010–2017) from a long-term experiment in Iowa, USA, focusing on pH, available phosphorus (Bray1-P), and macro- and micronutrients (K, Ca, Mg, Cu, Fe, Zn) at two depths (0–5 and 5–15 cm). A convergent multi-method framework combined robust univariate statistics, multivariate ordination (PCA, PERMANOVA), linear mixed-effects models, and machine learning (Random Forest and Firth-penalized logistic regression). Results reveal a clear stratification–homogenization pattern. NT is associated with surface accumulation of Zn (+14%), Fe (+16%), and Cu (+5%), with mild acidification (–0.4 pH units) and high temporal stability. CT favored vertical nutrient redistribution, marked by subsurface K enrichment (up to 6% higher than NT), progressive alkalinization, and greater temporal variability. Predictive modeling highlighted subsurface K and surface Zn/Fe as key discriminators, with Firth regression confirming their complementary effects. These findings indicate that long-term NT and CT are associated with distinct, depth-specific chemical configurations—integrated systems defined by concentration gradients, temporal stability, and element covariation—rather than isolated element changes. This work provides a robust, quantitative framework for diagnosing soil management history and characterizing the pedochemical imprint of tillage. Full article

Background/Objectives: Bacteriophages offer a promising alternative to conventional antibiotics. However, their therapeutic efficacy is often limited by instability in harsh environmental conditions, particularly within the gastrointestinal tract. This study aimed to isolate lytic bacteriophages from wastewater and evaluate the protective capacity of sodium alginate encapsulation against various stressors to enable effective oral delivery. Methods: Four distinct lytic phages (As, Ec, Pa, Gc) were isolated from wastewater and characterized by Transmission Electron Microscopy (TEM) and PCR, confirming their families (Siphoviridae, Podoviridae, Myoviridae). These phages demonstrated potent lytic activity against diverse bacterial pathogens, including Aeromonas hydrophila, Escherichia coli, Pseudomonas aeruginosa, and Glutamicbacter creatinolyticus. The phages were encapsulated in 5% sodium alginate via an extrusion method. Stability was assessed under extreme pH (2.0 and 13), at elevated temperature (up to 80 °C), and in simulated gastrointestinal transit. Results: Encapsulation efficiency exceeded 95%. Unencapsulated phages were completely inactivated at pH 2.0 within 10 min, whereas encapsulated phages maintained significant viability (3.06–3.43 log PFU/mL). Encapsulation also significantly enhanced phage survival under extreme alkaline conditions and elevated temperatures. In simulated gastrointestinal transit, encapsulated phages exhibited superior recovery (2.50 log PFU/mL) compared to their free counterparts (≤1 log PFU/mL). Long-term storage evaluations over three months further confirmed the robust stability of the encapsulated formulations at both 4 °C and 21 °C. Conclusions: Sodium alginate encapsulation effectively shields bacteriophages from severe environmental degradation, particularly acidic gastric stress, enhancing their potential for oral delivery. These findings support the development of stable, formulated phage products for diverse practical applications in phage therapy to combat antimicrobial resistance. Full article