Search Results (8,797)

Lignocellulose represents an abundant repository of renewable carbon. Derived from various plant sources, it holds tremendous potential as a renewable and sustainable feedstock for the production of valuable chemicals and fuels. However, its solid fermentable compounds, cellulose and hemicellulose, are embedded within complex lignin structures and are therefore poorly accessible to microbial conversion. This paper describes an artificial rumen reactor (ARR) that uses anaerobic microbes from the cattle rumen to increase the release of fermentable carbon from recalcitrant biomass. We outline the development of an ARR for the efficient conversion of lignocellulosic grass into volatile fatty acids (VFAs), which are valuable precursors for the production of a range of bioproducts, including biofuels, biomaterials, and biochemicals. The ARR, a 4-L bioreactor equipped with a ceramic filtration unit, has been optimised and was operated for extended periods of continuous VFA production. Across distinct short- and long-term observation periods, and independent of the cow from which the rumen microbes originated, the bioreactor demonstrated the ability to sustain VFA production, indicating robustness and stability. At an input of 60–80 g dry grass d⁻¹, the system produced approximately 6 mol VFA per kg of dry matter input (DMI). The decoupling of the Solid Retention Time (SRT; 10 days) and the Liquid Retention Time (LRT; 0.5 days) prevented inhibition of the VFA production. The VFA profile was dominated by acetic and propionic acids, comprising 68% and 19%, respectively, with butyric acid and minor VFAs accounting for the remainder. The application of low oxygen levels (<10%) in the reactor via limited aeration did not affect the VFA yield or its profile. Full article

Background/Objectives: The growing prevalence of obesity necessitates innovative gut-targeted material strategies to modulate diet-associated metabolic dysfunction. This study investigates a spray-dried konjac glucomannan–montmorillonite (KGM-MMT) hybrid designed to integrate fermentable polysaccharide properties with luminal lipid-adsorptive clay functions within a single micro-engineered formulation. Methods: In HFD-fed mice treated for 42 days with 2% w/w KGM-MMT, cumulative body weight gain was attenuated by 7.6%, with an AUC of 5094 ± 52.95, compared to 5513 ± 81.35 in HFD controls (p < 0.0001). Results: Serum IL-6 concentrations were reduced by 97% (p = 0.0002), while blood glucose decreased by 46% (p < 0.0001); these effects were greater than those observed with MMT (24%, p = 0.0271) and KGM (16%, ns). Gut microbiota profiling demonstrated a significant 6.2-log₂-fold increase in Lactobacillaceae (p = 0.023) and a 2.4-log₂-fold increase in Enterococcaceae (p = 0.015) following KGM-MMT treatment. Functional shifts inferred from 16S rRNA gene-based prediction indicated a 1.9-fold increase in short-chain fatty acid-related pathways and a 5.4-fold increase in bile acid deconjugation pathways. Conclusions: Although the KGM-MMT hybrid did not consistently outperform its individual components across all endpoints, it consolidated complementary KGM- and MMT-associated effects within a single dosage form. These findings support spray-dried KGM-MMT as a gut-targeted biomaterial strategy that integrates multiple luminal and microbiota-associated functions within a single formulation. Future studies should define dose–response relationships, validate microbiota-derived functional predictions using higher-resolution approaches, and assess durability and safety under longer-term exposure. Full article

Chronic wounds resulting from bacterial infection remain one of the main challenges in clinical practice. There is a pressing need to develop an injectable hydrogel sealant with multifunctional properties, including remodeling capabilities, self-healing, painless removal, and antibacterial activity, to promote tissue remodeling. In this work, aldehyde carboxymethylated agarose (ACMA) is employed for the first time as a bio-template. Dopamine (DA) is introduced onto the ACMA template via a reversible Schiff-base reaction, endowing it with biomineralization properties to synthesize DA-modified ACMA-Ag nanoparticles (ACMA-DA-Ag). Further, the prepared ACMA-DA-Ag, which possesses both antibacterial activity and injectable behavior, is incorporated into a guar gum hydrogel through the formation of borate/diol bonds, thereby forming a multiple-dynamic-bond crosslinked network. This hydrogel demonstrates adequate mechanical strength, injectability, remodeling capabilities, and self-healing performance. It can reassemble into a new hydrogel within 4 ± 0.6 min upon simple physical contact, and supports tissue adhesion. Furthermore, the hydrogel effectively covers irregular-shaped wound and can be removed without causing secondary injury. More importantly, this multifunctional hydrogel is cost-effective, easy to synthesize, and simple to use, significantly accelerating skin regeneration and promoting the formation of skin appendages, such as hair follicles. The outcome of this research not only serves a tissue sealant for wound healing, but also presents a new strategy for creating novel polysaccharide-based biomaterials. Full article

Bone tissue engineering requires biomaterials capable of simultaneously supporting regeneration and preventing infection. Platelet-rich fibrin (PRF) has been widely used due to its autologous origin and growth factor release, but its rapid resorption limits its clinical applications. Albumin-PRF (Alb-PRF) membranes were developed to improve stability, and their combination with carbonated nanostructured hydroxyapatite (nCHA) may further reinforce osteoconductive properties. In this proof-of-concept study, we fabricated Alb-PRF, Alb-nCHA-PRF, and Alb-nCHA-PRF + doxycycline (DOX) membranes and characterized their physicochemical, antimicrobial, and biological performance in vitro. Membrane stability was monitored for up to 14 days; DOX incorporation and release were evaluated by autofluorescence and spectrophotometry; antimicrobial activity was assessed against E. faecalis and S. aureus; and MG-63 osteoblast-like cells were used to test cytocompatibility, proliferation, mineralization, and alkaline phosphatase (ALP) activity. The release of 27 cytokines and growth factors was quantified by multiplex immunoassay. Alb-PRF exhibited morphological integrity and an enhanced trophic secretome, and supported proliferation and late mineralization. nCHA incorporation reduced cell proliferation and secretome output, while DOX conferred sustained antibacterial activity and enhanced early ALP expression even with attenuated cytokine release, positively impacting mineralization, when compared to nCHA alone. These preliminary results provide preliminary feasibility evidence that Alb-PRF can be engineered as a multifunctional scaffold combining antimicrobial and regenerative functions, though some trade-offs indicate the need for dose optimization and validation with in vivo models. Full article

The reliability of adhesive bonding to CAD/CAM resin composites is influenced not only by material composition and surface treatment but also by the testing methodology used to assess bond strength. However, the impact of different shear bond strength (SBS) test configurations remains insufficiently clarified. This study evaluated the influence of different surface pretreatment protocols and SBS test methods on the bonding performance of a self-adhesive resin cement to two CAD/CAM materials: a conventional particulate-filled composite (Cerasmart 270) and an experimental short glass fiber-reinforced composite (SFRC CAD). Specimens (14 × 12 × 3 mm; n = 80 per material) were ground with 320-grit silicon carbide paper and divided according to surface pretreatment: airborne-particle abrasion (APA) or APA followed by hydrofluoric acid application for 60 s (APA + HF). Each group was further subdivided based on the SBS test method using either resin cement cylinders fabricated with a custom transparent mold (diameter: 3.6 mm; height: 3 mm) or metallic cylinders cemented to the treated surface. Half of the specimens were tested after 48 h of water storage, while the remainder underwent hydrothermal aging by boiling in water for 16 h prior to testing. Material type, SBS test method, surface pretreatment, and aging significantly affected bond strength (p < 0.05). The metallic cylinder method produced higher SBS values than the transparent mold technique, particularly for SFRC CAD. APA + HF tended to reduce SBS in Cerasmart 270, particularly after aging, whereas SFRC CAD showed comparable or higher bond strength values with APA alone. Aging decreased SBS in most groups. Overall, bond strength was influenced by both material type and test methodology. Within the limitations of this study, airborne-particle abrasion alone may be sufficient for SFRC CAD materials, while additional HF treatment may not provide further benefit. These findings highlight the importance of considering both material characteristics and test configuration when interpreting laboratory bond strength data. Full article

Diabetes mellitus is primarily caused by the loss or malfunction of insulin-producing β-cells, and although current therapies improve glycemic control, they do not restore physiologic insulin secretion. Advances in stem cell biology and organoid engineering have led to the development of pancreatic organoids and induced pluripotent stem cell (iPSC)-derived β-cells as promising platforms for disease modeling, drug testing, and regenerative medicine. Pancreatic organoids generated from ductal, acinar, or progenitor populations can recapitulate key anatomical and functional features of native pancreatic tissue, enabling studies of development, injury, and regeneration. In parallel, improvements in iPSC differentiation protocols have produced β-like cells capable of insulin secretion in response to glucose, although achieving full functional maturity remains a challenge. Bioengineering strategies, including biomaterial scaffolds, microfluidic platforms, endothelial co-culture systems, three-dimensional bioprinting, and CRISPR-based genome editing, have enhanced the stability, vascular compatibility, and functional performance of both organoid and iPSC-derived systems. Despite these advances, variability in differentiation efficiency, limited β-cell maturity, and poor long-term survival continue to hinder clinical translation. Together, pancreatic organoids and iPSC-derived β-cells represent complementary platforms that advance fundamental research and support the development of β-cell replacement therapies, with ongoing integration of bioengineering approaches expected to accelerate progress toward reproducible, scalable, and clinically relevant β-cell regeneration. Full article

The growing environmental impacts associated with conventional plastics and textiles have intensified interest in bio-based and circular material alternatives. This study presents a qualitative and structured literature review of the valorization of fruit and nut agricultural residues as sustainable feedstocks for biomaterials and biotextiles, with a strategic focus on Greece. Drawing on international literature, regional agricultural production data, and validated processing technologies, the review synthesizes existing evidence on residue availability, conversion routes, environmental performance, and market trends. The reviewed literature indicates that residues such as grape pomace, olive by-products, citrus peels, and nut shells have been widely reported as suitable sources of cellulose, lignin, and pectin for the development of fibers, films, and composite materials. Findings from published life cycle assessment (LCA) studies suggest potential reductions in water use, greenhouse gas emissions, and land-use intensity compared with conventional cotton and synthetic textiles, although results vary depending on system boundaries and processing conditions. The review further highlights enabling factors, technical limitations, and policy considerations relevant to the Greek context. This study provides a qualitative integrative perspective on the opportunities and constraints associated with agricultural residue valorization, identifying key research gaps and strategic directions for future development within Greece and similar Mediterranean regions. Full article

The construction sector remains a major contributor to global energy consumption and greenhouse gas emissions. Heat loss through building envelopes plays a key role, especially in regions with long heating seasons. Hollow building blocks are widely used due to their low cost and structural simplicity, but their inadequate thermal insulation requires additional layers of insulation, increasing costs and complicating installation. The production of cement and traditional insulation materials is associated with a high carbon footprint and disposal issues, which conflict with sustainable development principles and decarbonization goals. In contrast to previous reviews that primarily address bio-based insulation in general building envelopes or focus on bioaggregates in concrete mixes, this paper specifically targets the application of biomaterials in hollow building blocks. It emphasizes how bio-based loose-fill and bound fillers interact with the peculiar thermo-fluid behavior of hollow cavities, including natural convection, conduction and radiation. The effects on thermal performance (thermal conductivity, U-value of walls) are analyzed, along with selected aspects of mechanical strength and durability. Gaps in long-term data on biodegradation are identified. Recommendations for selecting strategies depending on climate and design are offered, as well as directions for future research, including numerical modeling of thermal conditions. The results highlight the potential of biomodified blocks for creating energy-efficient and environmentally friendly wall systems. Full article

Composite materials with Ti or Ti alloy reinforcement in a Zn matrix are new, promising materials with potential applications in implantology. Infiltrating zinc into the porous titanium reinforcement of a designed implant could improve its osseointegration. In this field, it is important to avoid the formation of brittle intermetallics; therefore, understanding their growth is fundamental. This work focuses on characterizing the Ti-Zn intermetallic phases at the interface of the TiAlV/Zn and Ti/Zn composites. Samples were prepared by immersing the Ti-6Al-4V or Ti bulk material in zinc melt at various temperatures. After various dwell times, the samples (pieces of Ti-6Al-4V or Ti in the molten zinc) were removed from the furnace and cooled in air. The sequence of evolution of intermetallic phases was observed to be dependent on dwell time at selected temperatures. The influences of surface treatment methods on the boundary structure were also tested. Full article

The reconstruction of complex orbitomaxillary defects requires biomaterials that can simultaneously provide structural stability, biocompatibility, and accurate restoration of facial volume and contour. While rigid polymers such as polyetheretherketone (PEEK) offer reliable mechanical support, they do not adequately replicate the viscoelastic behavior of soft tissues. This report presents a translational revision case employing a personalized hybrid biomaterial approach that combines a 3D-printed PEEK implant for structural orbital floor support with a patient-specific polydimethylsiloxane (PDMS) implant for malar volumetric augmentation. Reconstruction was planned using CT segmentation and contralateral mirroring. Patient-specific implants were subsequently designed using CAD/CAM techniques, combining a rigid PEEK implant for structural orbital support with a flexible PDMS implant for malar volumetric augmentation with complementary mechanical properties. Revision surgery included the removal of inadequately positioned titanium hardware, the release of incarcerated extraocular muscles, and the restoration of orbital anatomy and facial symmetry. Postoperative imaging demonstrated stable implant positioning and sustained orbitomaxillary stability. Despite successful anatomical reconstruction, residual functional sequelae, including strabismus related to the severity of the initial orbital trauma, persisted and were addressed separately in a staged manner, resulting in satisfactory ocular alignment and resolution of diplopia in primary gaze. This case underscores the complementary functional roles of rigid and elastic polymers and highlights the translational potential of PDMS as a permanent, patient-specific implant material for volumetric and contour restoration in craniofacial reconstruction. Full article

Bone marrow(BM) is the primary site of hematopoiesis, supporting the self-renewal and differentiation of hematopoietic stem cells (HSCs). Its function depends on a highly complex microenvironment composed of stromal cells, vascular networks, extracellular matrix components, and dynamic biophysical signals. Traditional two-dimensional culture systems and animal models fail to adequately recapitulate the spatial architecture and dynamic regulatory processes of the human bone marrow niche, thereby limiting in-depth investigations into hematopoietic regulatory mechanisms, disease pathogenesis, and drug-induced bone marrow toxicity. In recent years, advances in microphysiological systems (MPS) have provided novel engineering approaches for the in vitro reconstruction of the bone marrow microenvironment. This review systematically summarizes current construction strategies for bone marrow MPS, including three-dimensional self-organized bone marrow organoids and microfluidic bone marrow-on-a-chip platforms. Particular attention is given to the roles of key cellular components, biomaterial scaffolds, vascularized architectures, and dynamic perfusion systems in biomimetic bone marrow engineering. In addition, we discuss strategies for constructing more complex models, such as vascular niches, vascularized bone tissue constructs, and bone metastasis models. Bone marrow MPS more faithfully recapitulate the hematopoietic microenvironment and provide a physiologically relevant in vitro platform for hematopoietic research, disease modeling, and drug evaluation, thereby supporting future advances in precision and regenerative medicine. Full article

Thermal processing of biomass can induce chemical transformations that lead to the formation of fluorescent carbonaceous products. In this study, six β-glucan-rich medicinal mushrooms, Ganoderma lucidum, Cordyceps sinensis, Inonotus obliquus, Lentinula edodes, Grifola frondosa, and Hericium erinaceus, were subjected to mild pyrolytic treatment (200 °C for 3 h) to investigate the formation of water-soluble fluorescent fractions. Physicochemical characterization of aqueous extracts was performed using high-performance liquid chromatography size-exclusion chromatography (HPLC-SEC), fluorescence emission spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and β-glucan quantification. Fluorescence emission spectra revealed species-dependent differences in emission intensity, with the most pronounced signals observed for G. lucidum and C. sinensis. HPLC-SEC analysis showed only minor changes in molecular weight distribution after thermal treatment, suggesting limited polymer degradation. FTIR spectra indicated moderate structural modifications consistent with partial carbonization and chemical rearrangement within the mushroom matrices. Despite the mild processing conditions, measurable increases in fluorescence intensity were observed in several species, indicating the formation of fluorescent carbon-rich molecular structures. These findings demonstrate that moderate thermal treatment of β-glucan-rich fungal biomass can generate water-soluble fluorescent carbonaceous fractions without extensive breakdown of the original polysaccharide matrix. The results provide new insights into thermally induced photophysical changes in medicinal mushrooms and contribute to understanding the formation of fluorescent carbonaceous products from natural biomaterials. Full article

The rapid emergence of antibiotic-resistant bacteria represents one of the most critical challenges in modern healthcare and has stimulated intense research into alternative antimicrobial strategies. Antibacterial hydrogels have emerged as versatile biomaterials due to their high water content, tunable physicochemical properties, and ability to function as multifunctional platforms for drug delivery and tissue regeneration. This review analyzes recent advances in antibacterial hydrogel systems through a conceptual framework based on three complementary pillars: biological antibacterial agents, inorganic functional components, and structural material engineering. Biological strategies, particularly bacteriophage-based approaches, provide highly specific antibacterial activity capable of targeting multidrug-resistant pathogens and disrupting bacterial biofilms. Inorganic components such as hydroxyapatite nanoparticles contribute additional functionalities including drug adsorption, modulation of the ionic microenvironment, and osteoconductive behavior relevant for bone-related infections. Structural design strategies based on electrospinning enable the fabrication of fibrous architectures that enhance mechanical stability, regulate therapeutic release, and mimic extracellular matrix organization. The integration of these three pillars within multifunctional hydrogel platforms offers promising opportunities for developing advanced antibacterial biomaterials capable of addressing infection control while supporting tissue regeneration. Full article

The use of postmortem (autopsy) material in fundamental and applied biomedical research significantly facilitates the collection of biomaterial for statistically robust sample cohorts. However, natural adaptive processes to developing cellular stress in the early postmortem period, caused by oxygen and nutrient deprivation, trigger the activation of numerous genes promoting cell survival under stress. Many of these activated pathways are also crucial for tumor cell survival in vivo, as evidenced by various transcriptomic studies. This study aimed to investigate the potential influence of postmortem interval (PMI) duration on gene expression in normal and tumor tissues. Using a model of chemically induced hepatocellular carcinoma in mouse liver, we comparatively analyzed the dynamics of transcript levels for several genes (BRCA1, BRCA2, CHEK1, CHEK2, ATM, CDK12) in paired samples of normal and tumor tissue over a 24-h PMI using RT-qPCR. In normal tissue, gene expression increased significantly, while tumor tissue demonstrated relative transcriptional stability, with no substantial changes in the studied transcript levels. A critical finding was the observed convergence of expression profiles: initial differences between the tissues were completely eliminated by 24 h PMI. This pattern developed despite formally adequate RNA quality (RQN) and the absence of clear signs of progressive autolysis in histology, indicating the insufficiency of standard quality criteria for detecting postmortem changes. These findings collectively underscore the critical importance of minimizing and controlling PMI during the biobanking of oncological samples for reliable transcriptomic research. Full article

Background/Objectives: Biodegradable magnesium (Mg)-based biomaterials release Mg²⁺ ions during degradation and may promote vascular-related regeneration. However, their effects on lymphatic endothelial cells (LECs) and lymphangiogenesis remain unclear. This study investigated whether magnesium powder-derived ionic extracts could enhance lymphangiogenesis-related behaviors of LECs in vitro. Methods: Mg powder extracts were prepared and diluted for in vitro treatment. After viability screening, Mg (1:10), Mg (1:100), and Mg (1:1000) were selected for further analysis. LEC proliferation, migration, and tube formation were assessed, together with intracellular reactive oxygen species (ROS) levels and the expression of VEGFA, VEGFC, and VEGFR3. Results: Mg (1:10) and Mg (1:100) showed good cytocompatibility and significantly promoted LEC proliferation, migration, and tube formation compared with the control and Mg (1:1000) groups. These effects were accompanied by reduced intracellular ROS levels and increased expression of VEGFA, VEGFC, and VEGFR3. Conclusions: Magnesium powder-derived ionic extracts enhance lymphangiogenesis-related responses of LECs in vitro, particularly at the 1:10 and 1:100 dilutions. These findings support the potential of Mg-based biodegradable biomaterials for lymphatic tissue regeneration. Full article