Search Results (300)

Granule-bound starch synthase (GBSS) is primarily recognized for its role in amylose production and starch granule formation in plant plastids. While its biochemical function in storage organs has been well documented, its broader contribution to plant growth and stress adaptation remains less defined. To explore these aspects, the maize gene ZmGBSS1 was ectopically expressed in Arabidopsis thaliana and its physiological effects were examined. Subcellular localization assays confirmed that ZmGBSS1 is specifically localized to chloroplasts. Phenotypic analysis of transgenic lines revealed that overexpression of ZmGBSS1 significantly altered early seedling development, promoted root elongation, and accelerated flowering, with flowering occurring approximately four days earlier than in wild-type plants. Changes in development were accompanied by increased starch accumulation, elevated amylose levels, and a higher abundance of enlarged starch granules within chloroplasts. Under drought and PEG-induced osmotic stress, transgenic plants maintained improved growth performance and recovery capacity, together with greater proline accumulation and chlorophyll retention. These physiological advantages coincided with more rapid starch utilization and clear rises in transcripts for proline synthesis enzymes (AtP5CS1, AtP5CS2) and starch-degrading proteins (AtBAM1, AtBAM3, AtDPE1). Collectively, these findings suggest that ZmGBSS1 not only regulates starch biosynthesis but also plays a crucial role in coordinating plant development and drought stress responses, highlighting its potential for improving stress tolerance through metabolic regulation. Full article

Curcumin, a natural polyphenol derived from Curcuma longa, is widely recognized for its therapeutic properties. However, its clinical utility is limited because of poor solubility, rapid degradation and hence low bioavailability. To overcome these issues, nanoformulation approaches, especially PEGylated liposomes, have been explored as advanced delivery systems. PEGylation, which involves attaching polyethylene glycol (PEG) to the liposomal surface, enhances circulation time by creating a steric shield that reduces protein interactions and clearance by the mononuclear phagocyte system (MPS). However, PEG can alter lipid membrane properties, which may in turn affect curcumin’s solubility and distribution within the liposomal bilayer, ultimately reducing its loading efficiency. To ensure that PEG-modified liposomes can be effectively loaded with curcumin, we investigated curcumin–membrane interactions in saturated (DMPC) and unsaturated (POPC) liposomes, both in the presence and absence of PEG. Based on dissociation constants (K_d) obtained from fluorescence spectroscopy measurements, we found that PEGylated DMPC liposomes exhibit the strongest binding affinity for curcumin. Fluorescence quenching experiments showed that curcumin adopts a transbilayer orientation in all membranes examined. Curcumin’s location within PEGylated and non-PEGylated liposomal membranes was further confirmed by examining its effects on membrane properties, including fluidity, polarity, and oxygen transport. These effects were investigated using electron paramagnetic resonance (EPR) spectroscopy with spin labels. The results indicate that PEG does not impose major changes on membrane properties. Curcumin, however, was found to reinforce the liposomal membranes, increase their polarity, and reduce oxygen availability. Overall, the findings suggest that liposomes, particularly those composed of PEGylated DMPC, are effective vehicles for curcumin delivery. Full article

This study evaluated the effects of increasing proportions of sudangrass sorghum forage in ruminant diets, with or without polyethylene glycol (PEG), on rumen fermentation, gas and methane production, nutrient digestibility, and protein fermentation metabolites. Three experimental diets containing 20%, 40%, or 60% sorghum forage (S20, S40, and S60) were incubated in vitro with cattle rumen fluid. Incubations were performed with or without PEG used as a tannin-binding agent. After 24 h of incubation, gas and methane production, in vitro dry matter digestibility (DMD), neutral detergent fiber digestibility (NDFD), ammonia nitrogen concentration (N-NH₃), and volatile fatty acid (VFA) production and profiles were measured. Increasing sorghum inclusion resulted in a significant reduction in DMD (p = 0.0012). In contrast, NDFD increased (p = 0.0005), likely due to differences in lignin content among diets. Methane production was unaffected by the proportion of sorghum, despite the increasing tannin content. PEG supplementation significantly increased N-NH₃ concentration (p = 0.042) and isobutyric molar proportion (p < 0.0001), indicating enhanced rumen protein degradation following tannin neutralization. The total VFA concentration was not influenced by either sorghum level or PEG treatment. However, higher sorghum inclusion was associated with shifts in the VFA profiles toward higher acetate (p = 0.0023) and lower butyrate proportions (p = 0.0114). Overall, the results suggest that moderate levels of condensed tannins (CTs) in sorghum forage may alter rumen fermentation patterns without markedly reducing methane production. PEG supplementation further confirmed the biological activity of tannins, especially regarding protein metabolism. Therefore, sudangrass sorghum may be considered a viable forage option for ruminant diets, provided its inclusion level and tannin effects are carefully managed. Full article

Background/Objectives: Selection of polymer carriers for targeted drug delivery is typically guided by material availability or trigger responsiveness rather than disease-specific evidence. However, successful preclinical formulations may already encode implicit design rules linking polymer composition to particular pathological environments. This study aimed to identify reproducible material-disease associations across biodegradable polymer systems and to derive formulation-oriented guidance for disease-calibrated carrier selection. Methods: A structured synthesis of 65 preclinical in vivo studies (2020–2025) covering inflammatory bowel disease, arthritis, cardiovascular inflammation, and solid tumors was performed. Extracted variables included polymer family, backbone chemistry, stimulus responsiveness, disease model, and reported therapeutic benefit relative to controls. Associations between polymer composition, trigger mechanisms, and disease categories were analyzed using cross-tabulation, chi-square statistics, Cramér’s V, and direction-of-effect synthesis. Results: Distinct material-disease clustering patterns emerged. Ionizable polysaccharide and methacrylate systems (e.g., alginate, chitosan, Eudragit) were strongly associated with intestinal inflammatory models, reflecting reliance on pH- and ion-mediated mechanisms. Enzyme-degradable hyaluronic acid matrices were concentrated in joint and cartilage disorders characterized by protease overexpression. Oxidation-sensitive polyether systems (e.g., PEG-PPS) and redox-active hybrid platforms predominated in atherosclerosis and tumor models, where oxidative stress is a defining pathological feature. Composite and multi-responsive systems were disproportionately represented in tumors, consistent with microenvironmental heterogeneity. Across studies, therapeutic improvement was consistently reported when polymer functional motifs aligned with dominant biochemical drivers of the disease. Conclusions: Successful biodegradable polymer carriers exhibit disease-specific compatibility patterns rather than universal applicability. These recurring associations suggest that polymer selection can be guided by pathological context even in the absence of direct outcome comparisons. The resulting formulation-oriented framework supports rational carrier choice for personalized drug delivery based on disease-specific microenvironment signatures. Full article

Three-dimensional (3D) bioprinting has rapidly emerged as a transformative technology at the interface of biomedical engineering and regenerative medicine. By enabling the spatially controlled deposition of living cells, biomaterials, and bioactive molecules, it offers an unprecedented potential to fabricate functional tissues and potentially whole organs in the future. This review explores recent advances in bioprinting materials, processes, and applications, emphasizing the integration of bioinks, printing methods, and mechanical design principles that underpin tissue functionality. Natural and synthetic biomaterials such as hydrogels (e.g., collagen, alginate), polyethylene glycol (PEG), and polyesters like PLGA are evaluated in terms of biocompatibility, printability, and degradation behavior. Key bioprinting modalities, including extrusion, inkjet, and laser-assisted bioprinting, are compared based on printing resolution, cell viability, and scalability. Structural considerations such as scaffold architecture, mechanical stability, and biomimetic design are discussed in relation to native tissue mechanics and requirements. The review also surveys emerging applications in tissue engineering (e.g., bone, cartilage, skin replacements), organ-on-a-chip systems for drug testing, and patient-specific implants, while addressing persistent challenges such as standardization of biofabrication, regulatory and ethical considerations, and manufacturing scale-up. Finally, future trends, including the integration of artificial intelligence (AI) and robotic automation, multi-material and four-dimensional (4D) bioprinting, and the maturation of personalized bioprinting strategies, are highlighted as pathways toward more autonomous and clinically relevant bioprinting systems. Collectively, these developments signify a paradigm shift in how biological constructs are designed and manufactured, bridging the gap between laboratory research and clinical translation. Full article

Background: The long-term stability of mRNA-lipid nanoparticles (LNPs), essential for mRNA vaccines and gene therapies, relies on managing physicochemical properties to preserve their integrity and effectiveness through optimized formulation components. This study systematically evaluated LNP formulations with varied compositions, e.g., Dlin-MC3-DMA and ALC-0315 as ionizable lipids, and DMG-PEG2k or ALC-0159 as polyethylene glycol (PEG)-lipids, stored at −80 °C, −20 °C, 5 °C, and 25 °C in Tris buffer (pH 7.4) for 12 months. Methods: Sixteen quality attributes were analyzed, including particle size, mRNA encapsulation, lipid oxidation, and transfection efficiency over different formulations and storage temperatures to mechanistically evaluate the long-term stabilities. Results: Formulations stored at −80 °C and −20 °C retained acceptable stability, while storage at 5 °C caused aggregation, reduced in vivo expression, and mRNA degradation. Storage at 25 °C led to complete loss of transfection within six months. Mechanistic studies identified oxidative and hydrolytic lipid degradation (e.g., DSPC) in ALC-0315 formulations and MC3 N-oxidation with subvisible particulates in MC3-containing LNPs as primary failure modes. Increasing Tris buffer concentration accelerated 5′-cap hydrolysis, emphasizing the importance of a low-ionic-strength buffer for LNP formulations. Conclusions: Findings re-emphasize the necessity of deep-cold storage (≤−20 °C) and optimized formulation components to preserve mRNA–LNP integrity, offering insights for designing next-generation LNPs with improved shelf-life. Full article

Skin aging could lead to dermal collagen loss and elastic fiber degradation, ultimately manifesting as skin laxity. We aimed to counteract this by using poly-L-lactic acid (PLLA) microsphere (MS)-based fillers to facilitate long-term volume restoration through collagen regeneration. However, conventional MSs exhibit limitations such as broad size distribution and surface irregularities, which are frequently associated with significant adverse reactions. This study employed shirasu porous glass (SPG) membrane emulsification to fabricate uniform and well-shaped polyethylene glycol-block-poly (L-lactic acid) (PEG-PLLA) MSs. A single-factor experiment was employed to optimize the parameters. The optimal preparation conditions for PEG-PLLA MSs were as follows: PEG-PLLA concentration of 40 mg/mL, polyvinyl alcohol (PVA) concentration of 0.5%, and magnetic stirring speed of 200 rpm. Under the optimal conditions, the average particle size of PEG-PLLA MSs was 58.982 μm, and the span value (SPAN) was 1.367. In addition, a cytotoxicity assay was performed, and the results revealed no significant toxicity of the MSs toward L929 mouse fibroblasts at concentrations below 500 μg/mL. Furthermore, PEG-PLLA MSs significantly enhanced the production of key extracellular matrix (ECM) components—type I collagen (Col-I), type III collagen (Col-III), and hyaluronic acid (HA)—while simultaneously alleviating cellular oxidative stress responses. This work offers a reliable and reproducible fabrication strategy for developing biocompatible MS fillers with controllable particle sizes. Full article

This study focuses on fabrication and comprehensive characterization of gold nanoparticles (AuNPs) stabilized with polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG), correlating polymer degradation with colloidal stability and localized surface plasmon resonance (LSPR) behavior under controlled gamma doses from 5 to 125 Gy. AuNPs were synthesized via laser-assisted synthesis (LAS) in aqueous medium containing PVP or PEG as a stabilizing and capping agent. Morphology, size distribution, and surface functionalization of the resulting AuNPs@polymer-stabilized were verified through UV-Vis spectroscopy, FTIR, XRD, DLS, zeta potential, and TEM. Results show that the polymer shell effectively preserved the nanoparticles’ integrity by minimizing aggregation and maintaining LSPR features even after exposure to high gamma doses (>75 Gy). PVP demonstrated superior protection compared to PEG, due to the robustness of the solvation layer and carbonyl groups of PVP coating around the AuNPs. These findings highlight the potential of polymer-stabilized AuNPS for applications in radiation-rich environments, while demonstrating LAS as an environmentally friendly and efficient synthesis route. Full article

Background: Chronic diabetic wounds, particularly diabetic foot ulcers (DFUs), are prone to recurrent infection and delayed healing, resulting in substantial morbidity, mortality, and economic burden. Multifunctional wound dressings that combine antibacterial, antioxidant, conductive, and self-healing properties may help to address the complex microenvironment of chronic diabetic wounds. Methods: In this study, ε-poly-L-lysine and amino-terminated polyethylene glycol were grafted onto carboxylated single-walled carbon nanotubes (SWCNTs) via amide coupling to obtain ε-PL-CNT-PEG. Aminated chondroitin sulfate (CS-ADH) and a catechol–metal coordination complex of protocatechualdehyde and Fe³⁺ (PA@Fe) were then used to construct a dynamic covalently cross-linked hydrogel network through Schiff-base chemistry. The obtained hydrogels (Gel0–3, Gel4) were characterized for photothermal performance, rheological behavior, microstructure, swelling/degradation, adhesiveness, antioxidant capacity, electrical conductivity, cytocompatibility, hemocompatibility, and antibacterial activity in the presence and absence of near-infrared (NIR, 808 nm) irradiation. Results: ε-PL-CNT-PEG showed good aqueous dispersibility, NIR-induced photothermal conversion, and improved cytocompatibility after surface modification. Incorporation of ε-PL-CNT-PEG into the PA@Fe/CS-ADH network yielded conductive hydrogels with porous microstructures and storage modulus (G′) higher than loss modulus (G′′) over the tested frequency range, indicating stable gel-like behavior. The hydrogels exhibited self-healing under alternating strain and macroscopic rejoining after cutting. Swelling and degradation studies demonstrated pH-dependent degradation, with faster degradation in mildly acidic conditions (pH 5.0), mimicking infected chronic diabetic wounds. The hydrogels adhered to diverse substrates and tolerated joint movements. Gel4 showed notable DPPH• and H₂O₂ scavenging (≈65% and ≈60%, respectively, within several hours). The electrical conductivity was 0.19 ± 0.0X mS/cm for Gel0–3 and 0.21 ± 0.0Y mS/cm for Gel4 (mean ± SD, n = 3), falling within the range reported for human skin. In vitro, NIH3T3 cells maintained >90% viability in the presence of hydrogel extracts, and hemolysis ratios remained below 5%. Hydrogels containing ε-PL-CNT-PEG displayed enhanced antibacterial effects against Escherichia coli and Staphylococcus aureus, and NIR irradiation further reduced bacterial survival, with some formulations achieving near-complete inhibition under low-power (0.2–0.3 W/cm²) 808 nm irradiation. Conclusions: A dynamic, conductive hydrogel based on PA@Fe, CS-ADH, and ε-PL-CNT-PEG was successfully developed. The hydrogel combines photothermal antibacterial activity, antioxidant capacity, electrical conductivity, self-healing behavior, adhesiveness, cytocompatibility, and hemocompatibility. These properties suggest potential for application as a wound dressing for chronic diabetic wounds, including diabetic foot ulcers, although further in vivo studies are required to validate therapeutic efficacy. Full article

This study aimed to control rapid localized corrosion and inflammation of biodegradable magnesium implants by developing a pH-responsive mPEG-PLGA coating loaded with dexamethasone (Dex). The mPEG-PLGA layer was designed to selectively degrade in alkaline conditions, thereby moderating pH elevation at the implant surface while enabling controlled Dex release. By varying the molecular weight of mPEG and PLGA, the degradation rate and microsphere size were tunable, allowing adjustment of the drug release profile. Among the tested coating solution concentrations (1.5–7.5 mg/mL), the formulation with 3 mg/mL Dex yielded a final cumulative release concentration of 0.02 mg/mL over a two-week period, which suppressed inflammatory responses in RAW 264.7 macrophages with minimal cytotoxicity, while enhancing BMP-2 and RUNX2 expression in mesenchymal stem cells. In a rat femur defect model, Mg implants coated with mPEG-PLGA containing 3 mg/mL Dex significantly increased bone volume and bone mineral density and reduced early TNF-α expression, accompanied by continuous new bone formation and strong BSP-positive osseointegration. These findings suggest that the proposed pH-responsive mPEG-PLGA/Dex coating provides a promising strategy to simultaneously regulate corrosion, attenuate inflammation, and promote bone regeneration around magnesium implants. Full article

Dynamic covalent hydrogels exhibiting multi-responsive and antibacterial properties offer significant potential for biomedical applications, including smart wound dressings and controlled drug delivery. Herein, a series of amphiphilic quaternized copolymers (Q-C8PEG-n) with tunable quaternization degrees was synthesized from C8PEG via iodomethane addition and characterized by ¹H NMR, COSY, FTIR, UV-vis spectroscopy, DLS, TEM, and zeta potential analyses, confirming successful quaternization and micelle formation. These copolymers displayed thermosensitive behavior, with cloud point temperatures increasing due to enhanced hydrophilicity. Q-C8PEG-3 micelles, incorporating diethanolamine units, were crosslinked with phenylboronic acid-grafted hyaluronic acid (HA-PBA) to yield dynamic covalent hydrogels (Gel) through reversible boronic ester bonds stabilized by B-N coordination. The Gel exhibited multi-responsiveness, undergoing degradation in acidic or alkaline conditions and exposure to glucose or H₂O₂. SEM confirmed a porous microstructure, enabling efficient drug encapsulation, as demonstrated by the release of Nile red (NR). In vitro antibacterial tests revealed enhanced post-quaternization efficacy, with the Gel showing strong activity against S. aureus. This micelle-crosslinked platform synergistically combines tunable stimuli-responsiveness with inherent antibacterial properties, holding promise for applications in wound healing and tissue engineering. Full article

Wind turbine blades (WTBs) have always been considered one of the greatest engineering achievements. They primarily use glass fiber-reinforced polymers (GFRPs) because of their lightweight nature, impressive strength-to-weight ratio, and durability. Until now, typical disposal methods of End-of-Life (EoL) WTBs are landfill or incineration. However, such practices are neither environmentally sustainable nor compliant with current regulations. This study investigates a low-temperature solvolysis process using a poly(ethylene glycol)/NaOH system under ambient pressure for efficient decomposition of the polyester matrix, promoting the potential of chemical recycling as an alternative to landfilling and incineration by offering a viable method for recovering glass fibers from WTB waste. A parametric study evaluated the influence of reaction time (4–5.5 h) and catalyst-to-resin ratio (0.1–2.0 g NaOH per g resin) on solvolysis efficiency. Optimal conditions (200 g PEG200, 12.5 g NaOH, 10 g GFRP, 5.5 h) achieved an ~80% decomposition efficiency and fibers exhibiting minimal surface degradation. SEM and EDX analyses confirmed limited morphological damage, while excessive NaOH (>15 g) caused notable etching of the glass fibers. ICP-OES of liquid residues detected high Na (780 mg/L) and Si (139 mg/L) concentrations, verifying partial dissolution of the fiber structure under strongly alkaline conditions. After applying a commercial sizing agent (Hydrosize HP2-06), TGA confirmed ~1.2% sizing mass, and nanoindentation analysis showed the interfacial modulus and hardness of re-sized fibers improved by over 70% compared to unsized recycled fibers, approaching the performance of virgin fibers. Full article

Accurate suction control underpins thermo-hydro-mechanical (THM) characterization of unsaturated soils, yet conventional polyethylene-glycol (PEG) osmotic methods suffer from membrane degradation, polymer intrusion, and marked temperature sensitivity. This study evaluates a potassium-neutralized poly (acrylamide-co-acrylic acid) hydrogel (PP) as a high-suction osmotic medium for water-retention testing of compacted kaolin using a sealed cell with a grade-42 filter paper separator (no semi-permeable membrane). The water-activity–suction relation of PP was calibrated with a chilled-mirror hygrometer (WP4C) over the high-suction domain, and temperature effects were assessed between 20–30 °C. The PP imposed stable target suctions across the practical engineering range, with cross-validation to WP4C of R² ≈ 0.985 and RMSE ≈ 0.09 MPa, and exhibited modest thermal sensitivity (~2–3% per 10 °C). Mass–time records showed a two-regime equilibration (rapid first-day moisture loss then slowing to asymptote), with time to 95% equilibrium t₉₅ ≈ 3–7 days depending on suction, and equilibrium within ~2 weeks under a normalized mass change, ${\displaystyle \frac{1}{m}}\left|{\displaystyle \frac{∆m}{∆t}}\right|<{\displaystyle \frac{0.1\%}{24h}}$ criterion. The resulting kaolin water-retention curves are smooth soil moisture factor (SMF) reproducible, and exhibited minor wetting–drying hysteresis (~20–25% gap at matched suctions). Collectively, the results indicate that PP provides a practical, membrane-free (in the semi-permeable sense) and accurate means to control high-range suction for unsaturated soil testing, showing only modest suction variations within the tested 20–30 °C range, while mitigating long-standing PEG limitations and simplifying laboratory workflows. Full article

Ruminant production in the Chaco region relies on pastures and native forest foliage, whose nutritional value is poorly characterized and may be influenced by tannins. This study evaluated the in situ digestibility and in vitro ruminal fermentation of foliage from Prosopis affinis (PA), Prosopis nigra (PN), Acacia polyphylla (AP), Phyllostylon rhamnoides (PR), and Tabebuia nodosa (TN), incubated with or without polyethylene glycol (PEG) to assess the effects of tannin on gas production and nitrogen (N) compounds degradability. Foliage contained ≥17% crude protein (CP) and ≥40% fiber-bound N. Tannin concentration was >4% dry matter (DM) in PN and PA and <1% DM in PR, AP, and TN. In situ digestibility was ≤51% in all species except PR (73%; p < 0.05). Gas production was higher in PA, PR, and TN (p < 0.05), with no PEG effect. Methane production was not affected by tree species or PEG (p ≤ 0.277). Both species and PEG affected the effective N compounds degradability (END), with PEG increasing it in PN and AP (p < 0.05). Although foliage is high in CP, its digestibility is low; N is largely fiber-bound, and tannins may further limit END, factors to consider when including them in ruminant diets. Full article

This study aimed to engineer nanofibrous scaffolds that prioritize architecture, rather than relying solely on the drug, to achieve reproducible, long-acting local therapies. Cotton-wool-like fiber, three-dimensional (3D) poly(L-lactic acid)/polyethene glycol (PLLA/PEG) blend scaffolds were fabricated using solution blow spinning (SBS) as a customizable encapsulation platform for controlled antibiotic release. Morphological and wettability analyses were performed by scanning electron microscopy (SEM) and pendant-drop contact angle measurements, respectively. Fiber diameters were quantified using ImageJ. The chemical composition and thermal behavior were investigated by Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). In vitro, assays were conducted to assess the antimicrobial activity of vancomycin-loaded scaffolds against Staphylococcus aureus (disk diffusion method), as well as their cytocompatibility (Live/Dead assay in Vero cells) and hemocompatibility (ASTM F756-17 hemolysis test). All biological data were statistically analyzed using ANOVA with Tukey’s post-test, Mann–Whitney, and paired t-tests, with significance set at p ≤ 0.05. Structural optimization identified PLLA/PEG 85:15 as the most stable composition, producing homogeneous mats with high porosity and rapid wettability. Incorporation of vancomycin (10 wt.%) reduced the fiber diameter (0.23 ± 0.11 µm) compared with unloaded scaffolds (0.32 ± 0.17 µm), indicating drug–polymer interactions that modulated jet elongation. FTIR, DSC, and TGA analyses confirmed polymer miscibility and stabilization of VMC within the fibrous matrix, with no signs of degradation. Drug release exhibited a biphasic profile, with an initial burst during the first 72 h. PLLA/PEG–VMC scaffolds produced larger inhibition zones against S. aureus (18.55 mm ± 1.2 to 6.63 mm ± 0.2 at 120 h) compared with free VMC (12.91 mm ± 3.8 to 4.07 mm ± 0.6291), while blank scaffolds were inactive. Hemolysis remained within the range 2% < PLLA/PEG–VMC < 5%, indicating acceptable hemocompatibility according to ASTM standards. Although VCM-loaded PLLA/PEG scaffolds slightly reduced Vero cell viability, no statistically significant differences were observed compared with the control group. These findings demonstrate that the architecture of nanofibers presents itself as a potential platform for antimicrobial therapy with topical vancomycin in potential applications such as wound dressings or implant coatings. Full article