Reactive oxygen species (ROS) are chemically reactive oxygen derivatives which are capable of profoundly altering cellular pathways. Due to their ability to induce oxidative damage and damage cells, ROS have been explored as a promising avenue to combat cancer and treat pathogenic bacteria. Recent intersections in the development of nanotechnology and ROS-based therapeutics include engineered nanoparticles, enzyme-mimicking nanozymes, and metal-organic frameworks. These nanoplatforms allow refined control of spatiotemporal generation of ROS within desired tissue, improved ROS targeting of cancer lesions and at sites of bacterial infection, and concurrent delivery of ROS-incorporated, multi-therapeutic agents. In this review, we outline the fundamental principles and advancements of ROS-based nanotherapies that have been used against both malignant cells and pathogenic bacteria, including photodynamic, sonodynamic, chemodynamic, and radiotherapeutic approaches. In addition, we explore strategies that combine ROS with immunotherapy or antibiotics to elicit synergistic anti-cancer or antimicrobial effects. Although ROS-based therapies face challenges in the current landscape, including limited tissue penetration, toxicity, and difficulties with in vivo monitoring, there are ongoing efforts to address these hurdles. Once a better mechanistic understanding of ROS is established and key biosafety criteria are met, once these challenges are addressed, ROS-based nanotherapies can serve as a powerful tool against tumors and drug-resistant bacteria, enable more effective personalized treatments, and advance precision medicine.

Tissue engineering and regenerative medicine (TERM) rely on advanced biomaterials and scaffolds that require strict sterilization without sacrificing their structural and functional properties. Conventional sterilization methods, including steam, ethylene oxide, and gamma irradiation, often compromise scaffold integrity, alter surface chemistry and/or leave toxic residues. Ozone (O3) has emerged as a promising alternative sterilant because of its strong oxidizing potential, broad-spectrum antimicrobial activity, and residue-free decomposition. Importantly, ozone sterilization can preserve—and in some cases enhance—scaffold bioactivity by maintaining cytocompatibility and favorable surface chemistries that support cell adhesion and differentiation. This review critically evaluates the role of ozone sterilization in the context of TERM applications, focusing on its physicochemical properties, disinfection kinetics, material compatibility and regulatory perspectives. Evidence from studies on polymethyl methacrylate (PMMA) scaffolds, bone implants, and hydrogel-based systems suggests that, under optimized conditions, ozone can achieve high sterilization efficacy without significant degradation of mechanical or chemical properties. However, challenges related to process validation, health and safety considerations, and scalability remain. The review highlights opportunities for integrating ozone into automated biomanufacturing workflows and identifies key research gaps to support the broader adoption of ozone sterilization in TERM applications.

The design of new medical devices in biomedical engineering often necessitates the control of microbial load at the point of application, making antibacterial action valuable for numerous applications in the biomedical field. Nanotechnology products, such as silver nanoparticles (AgNPs), represent highly promising yet underexplored bioactive and antimicrobial agents that have attracted researchers' interest for integration into medical devices. This study focuses on stable suspensions of silver nanoparticles, characterized by using a range of complementary physicochemical techniques as well as bacterial cell cultures, while also demonstrating controlled entrapment of the nanoparticles in collagen-based gels. The findings reveal that highly stable suspensions of negatively charged AgNPs (~6 nm in size) consistently exhibit broad-spectrum antimicrobial activity against both Gram-negative and Gram-positive bacteria, with minimum inhibitory concentration values of 10-20 ppm, whilst, importantly, close contact between the nanoparticles and bacterial cells turns out to be essential for their antibacterial action. Controlled entrapment of the nanoparticles in collagen-based gels enables regulation of nanoparticle release and their antimicrobial efficacy. This work highlights the promising prospects of silver nanoparticles in designing novel biomedical engineering products, while underscoring the need for a more comprehensive understanding of their biological activity to ensure optimal utilization.

Probiotic and live biotherapeutic interventions frequently yield inconsistent clinical benefits despite strong mechanistic rationale and widespread use. We propose that this heterogeneity reflects the ecological state of the gut at the time of dosing, in which an introduced strain must invade an already occupied ecosystem shaped by host physicochemical filters and resident community interactions. We introduce microbial niche tension as a trial-operational state variable capturing the net impedance to engraftment imposed by exclusionary forces (resource competition, antagonism, spatial crowding, and host immune and chemical barriers) and facilitative forces (niche vacancy, cross-feeding, and transient permissive windows). We further define a niche tension index (NTI) as a quantitative framework to estimate engraftment permissiveness across space, time, and host contexts. We synthesize evidence showing that niche tension is structured by gut transit, pH, oxygen gradients, diet, antibiotics, and host factors, including sex and hormonal state. Finally, we outline design rules for precision probiotics, including niche preconditioning, cooperative guild construction, sex-aware stratification, and data-driven prediction tools, to improve reproducibility and clinical efficacy.

Batch fermentations of the wild type Yarrowia lipolytica MUCL 28849 were performed in a bench-top bioreactor to assess crucial operating conditions. A setup of carbon to nitrogen (mol/mol) ratio equal to 34, pH = 6.0 and 52 g/L of crude glycerol showed increased lipid production and complete glycerol consumption at t = 24 h, thus, selected for further process improvement. & Acy; semi-continuous process was implemented, where a pH drop to 4.0 at 24 h, interrupted citric acid secretion without affecting lipid production. An in-situ membrane module was employed for membrane bioreactor fermentations, where yeast cells were successfully retained with minimum fouling. The membrane bioreactor fed-batch process, resulted in a high-cell-density culture reaching 49.8 g/L of dry biomass and 4.9 g/L of lipids. An unstructured model was developed and successfully simulated operation under all fermentation modes, distinguishing diverse physiological shifts.

Cancer immunotherapy has revolutionized cancer treatment by leveraging the immune system to target and eliminate tumor cells. Implantable biomaterials, such as hydrogels, sponges, scaffolds, implantable microdevice platforms, and macrobeads, offer localized and sustained release of immunomodulatory agents, improving the delivery of treatments such as immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapies like CAR-T cells. This review examines the emerging role of these biomaterials in modulating the tumor microenvironment, enhancing immune cell recruitment, and reducing systemic side effects, positioning them as significant tools for treating solid tumors. Recent advances in material engineering are also discussed, including the integration of bioactive molecules and real-time therapeutic adjustments based on patient-specific immune responses, which offer new potential in personalized cancer treatments. However, challenges such as biocompatibility, high production costs, variability in patient response, and the necessity of surgical manipulations remain key obstacles. Nonetheless, ongoing research and technological advancements are steadily addressing these issues, paving the way for more effective and accessible cancer immunotherapies. Overall, this review highlights the promise of implantable biomaterials overcoming the current limitations of cancer immunotherapy and expanding the scope of effective, targeted cancer treatments.

Silver nanoparticles (AgNPs) are highly promising components for the development of innovative biomedical products. However, a critical issue remains the insufficient deep and quantitative understanding of their fundamental physicochemical properties. These properties essentially govern the bioactivity of silver nanoparticles and, consequently, the success of their biomedical applications. Current characterization methods do not fully capture the complex nature of AgNPs, leaving key questions unresolved, such as detailed surface properties, dynamic interactions in real biological environments, long-term changes, and the release of silver ions—all factors that influence the toxicity and performance of the nanoparticles. This gap in knowledge complicates the reproducibility of experiments, comparison of results, and proper evaluation of potential health risks associated with their use. While advanced techniques such as Atomic Force Microscopy (AFM), Inductively Coupled Plasma (ICP) spectroscopy, and X-ray Photoelectron Spectroscopy (XPS) further significantly our understanding, they still do not fully meet all the demands for understanding silver nanoparticles. Specifically, these methods face limitations in monitoring the dynamic and complex interactions of nanoparticles within real biological settings, especially physicochemical properties that are linked to toxicity and also the biological. Therefore, despite their invaluable role, these techniques represent only part of the solution for the thorough understanding and assessment of the biomedical performance of AgNPs, highlighting the need for continued research to ensure their safe and efficient biomedical utilization.

This review article provides a comprehensive evaluation of Infuse® and InductOs®, two ground-breaking recombinant human Bone Morphogenetic Protein-2 (rhBMP-2)-based bone graft products, focusing on their tissue-level regenerative responses, clinical applications, and associated costs. Preclinical and clinical studies demonstrate that rhBMP-2 induces strong osteoinductive activity, effectively promoting mesenchymal stem cell differentiation and vascularized bone remodeling. While generally well-tolerated, these osteoinductive effects are dose-dependent, and excessive dosing or off-label use may result in adverse outcomes, such as ectopic bone formation or soft tissue inflammation. Histological and imaging analyses in craniofacial, orthopedic, and spinal fusion models confirm significant bone regeneration, positioning rhBMP-2 as a viable alternative to autologous grafts. Notably, advances in delivery systems and scaffold design have enhanced the stability, bioavailability, and targeted release of rhBMP-2, leading to improved fusion rates and reduced healing times in selected patient populations. These innovations, alongside its proven regenerative efficacy, underscore its potential to expand treatment options in cases where autografts are limited or unsuitable. However, the high initial cost, primarily driven by rhBMP-2, remains a critical limitation. Although some studies suggest overall treatment costs might be comparable to autografts when factoring in reduced complications and operative time, autografts often remain more cost-effective. Infuse® has not substantially reduced the cost of bone regeneration and presents additional safety concerns due to the rapid (burst) release of growth factors and limited mechanical scaffold support. Despite representing a significant advancement in synthetic bone grafting, further innovation is essential to overcome limitations related to cost, mechanical properties, and controlled growth factor delivery.

The effect of biomechanical signals induced by a non-toxic and biocompatible gel on Non-Small Cell Lung Cancer cells is investigated in this preliminary study. Gelatin type A, chitosan, and alginate were compared in a quantitative manner by means of rheology, in order to assess the most stable and easily prepared gel in physiological solution conditions for 3D cancer cell culturing. Crucial factors that influence the fabrication of the gel were examined and quantified, including gelation kinetics, reactants’ contact time, and temperature, leading to the development of an optimal research protocol. Alginate was found to lead to the most suitable physiological gels and its effect on the cancer cells was examined using flow cytometry. The results implied that alginate gels interfered with the cancerous cells’ growth rate, as the live cells’ percentage was far lower compared to the reference cell culture. Thus, alginate is a promising material for biomedical engineering applications concerning 3D culturing of cancer cells and its further research and optimization are strongly suggested.

Bone regeneration using Bone Morphogenetic Proteins (BMPs) alongside various engineered scaffolds has attracted considerable attention over the years. The field has seen extensive research in preclinical animal models, leading to the approval of two products and guiding the quest for new materials. Natural and synthetic polymers, ceramics, and composites have been used to fabricate the necessary porous 3D scaffolds and delivery systems for BMPs. Interestingly, all reported applications in the literature are triumphant. Evaluation of the results is typically based on histologic assessment after appropriate staining and radiological modalities, providing morphological identification of the newly formed bone and describing cells and the organic compound. Remarkably, while these evaluation methods illustrate mineralization, they are not capable of identifying hydroxyapatite crystals, the mineral component of the bone, which are crucial for its mechanical properties, structure, integrity, and long-term stability of regenerated bone tissue. This review aims to focus on the different scaffolds used in bone tissue engineering applications and underline the pressing need for techniques that could recognize the presence of hydroxyapatite crystals as well as their characteristics in bone tissue engineering, which will provide a more complete and comprehensive assessment of the successful results.

Fetal lung development is a crucial and complex process that lays the groundwork for postnatal respiratory health. However, disruptions in this delicate developmental journey can lead to fetal lung development disorders, impacting neonatal outcomes and potentially influencing health outcomes well into adulthood. Recent research has shed light on the intriguing association between fetal lung development disorders and the development of adult diseases. Understanding these links can provide valuable insights into the developmental origins of health and disease, paving the way for targeted preventive measures and clinical interventions. This review article aims to comprehensively explore the association of fetal lung development disorders with adult diseases. We delve into the stages of fetal lung development, examining key factors influencing fetal lung maturation. Subsequently, we investigate specific fetal lung development disorders, such as respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), congenital diaphragmatic hernia (CDH), and other abnormalities. Furthermore, we explore the potential mechanisms underlying these associations, considering the role of epigenetic modifications, transgenerational effects, and intrauterine environmental factors. Additionally, we examine the epidemiological evidence and clinical findings linking fetal lung development disorders to adult respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and other respiratory ailments. This review provides valuable insights for healthcare professionals and researchers, guiding future investigations and shaping strategies for preventive interventions and long-term care.

Τransforming growth factor β1 (TGF-β1) comprises a key regulator protein in many cellular processes, including in vivo chondrogenesis. The treatment of human dental pulp stem cells, separately, with Leu83-Ser112 (C-terminal domain of TGF-β1), as well as two very short peptides, namely, 90-YYVGRKPK-97 (peptide 8) and 91-YVGRKP-96 (peptide 6) remarkably enhanced the chondrogenic differentiation capacity in comparison to their full-length mature TGF-β1 counterpart either in monolayer cultures or 3D scaffolds. In 3D scaffolds, the reduction of the elastic modulus and viscous modulus verified the production of different amounts and types of ECM components. Molecular dynamics simulations suggested a mode of the peptides' binding to the receptor complex TβRII-ALK5 and provided a possible structural explanation for their role in inducing chondrogenesis, along with endogenous TGF-β1. Further experiments clearly verified the aforementioned hypothesis, indicating the signal transduction pathway and the involvement of TβRII-ALK5 receptor complex. Real-time PCR experiments and Western blot analysis showed that peptides favor the ERK1/2 and Smad2 pathways, leading to an articular, extracellular matrix formation, while TGF-β1 also favors the Smad1/5/8 pathway which leads to the expression of the metalloproteinases ADAMTS-5 and MMP13 and, therefore, to a hypertrophic chondrocyte phenotype. Taken together, the two short peptides, and, mainly, peptide 8, could be delivered with a scaffold to induce in vivo chondrogenesis in damaged articular cartilage, constituting, thus, an alternative therapeutic approach for osteoarthritis.

This work describes the design, preparation, and deep investigation of "intelligent nanobiomaterials" that fulfill the safety rules and aim to serve as "signal deliverers" for osteogenesis, harboring a specific peptide that promotes and enhances osteogenesis at the end of their hydrogel fibers. The de novo synthesized protein fibers, besides their mechanical properties owed to their protein constituents from elastin, silk fibroin and mussel-foot adhesive protein-1 as well as to cell-attachment peptides from extracellular matrix glycoproteins, incorporate the Bone Morphogenetic Protein-2 (BMP2) peptide (AISMLYLDEN) that, according to our studies, serves as "signal deliverer" for osteogenesis. The osteogenetic capacity of the biomaterial has been evidenced by investigating the osteogenic marker genes ALP, RUNX2, Osteocalcin, COL1A1, BMPR1A, and BMPR2, which were increased drastically in cells cultured on scaffold-BMP2 for 21 days, even in the absence of osteogenesis medium. In addition, the induction of phosphorylation of intracellular Smad-1/5 and Erk-1/2 proteins clearly supported the osteogenetic capacity of the biomaterial.

The regeneration of articular cartilage remains a serious problem in various pathological conditions such as osteoarthritis, due to the tissue's low self-healing capacity. The latest therapeutic approaches focus on the construction of biomaterials that induce cartilage repair. This research describes the design, synthesis, and investigation of a safe, "smart", fibrous scaffold containing a genetically incorporated active peptide for chondrogenic induction. While possessing specific sequences and the respective mechanical properties from natural fibrous proteins, the fibers also incorporate a Transforming Growth Factor-β1 (TGF-β1)-derived peptide (YYVGRKPK) that can promote chondrogenesis. The scaffold formed stable porous networks with shear-thinning properties at 37 °C, as shown by SEM imaging and rheological characterization, and were proven to be non-toxic to human dental pulp stem cells (hDPSCs). Its chondrogenic capacity was evidenced by a strong increase in the expression of specific chondrogenesis gene markers SOX9, COL2, ACAN, TGFBR1A, and TGFBR2 in cells cultured on "scaffold-TGFβ1" for 21 days and by increased phosphorylation of intracellular signaling proteins Smad-2 and Erk-1/2. Additionally, intense staining of glycosaminoglycans was observed in these cells. According to our results, "scaffold-TGFβ1" is proposed for clinical studies as a safe, injectable treatment for cartilage degeneration.

This paper presents a systematic review of a key sector of the much promising and rapidly evolving field of biomedical engineering, specifically on the fabrication of three-dimensional open, porous collagen-based medical devices, using the prominent freeze-drying process. Collagen and its derivatives are the most popular biopolymers in this field, as they constitute the main components of the extracellular matrix, and therefore exhibit desirable properties, such as biocompatibility and biodegradability, for in vivo applications. For this reason, freeze-dried collagen-based sponges with a wide variety of attributes can be produced and have already led to a wide range of successful commercial medical devices, chiefly for dental, orthopedic, hemostatic, and neuronal applications. However, collagen sponges display some vulnerabilities in other key properties, such as low mechanical strength and poor control of their internal architecture, and therefore many studies focus on the settlement of these defects, either by tampering with the steps of the freeze-drying process or by combining collagen with other additives. Furthermore, freeze drying is still considered a high-cost and time-consuming process that is often used in a non-optimized manner. By applying an interdisciplinary approach and combining advances in other technological fields, such as in statistical analysis, implementing the Design of Experiments, and Artificial Intelligence, the opportunity arises to further evolve this process in a sustainable and strategic manner, and optimize the resulting products as well as create new opportunities in this field.

Three-dimensional, open porous sensitive medical devices are increasingly attractive in biomedical engineering; at the same time new challenges immerse since traditional sterilization processes may not be appropriate for use with such sensitive devices. In the present study, we use a lyophilized nanostructured collagen sponge, as a model system of a sensitive medical device in order to study the effects of the two most common sterilization processes. Sterilization with gamma irradiation was found to cause profound effects on the internal structure illustrated by a change of the pore size from ca 70 mu m to heterogeneous 40-560 mu m. In contrast, ethylene oxide sterilization was seen to largely preserve the interior architecture, although it may alter permanently the surface properties of the sponge. This study helps to highlight the sterilization barriers that this kind of medical devices need to overcome. Copyright (C) 2023 Elsevier Ltd. All rights reserved.

Abstract Background Yarrowia lipolytica is a well-studied oleaginous yeast known for its ability to accumulate and store intracellular lipids, while growing on diverse, non-conventional substrates. Amongst them, crude glycerol, a low-cost by-product of the biodiesel industry, appears to be an interesting option for scaling up a sustainable single-cell oil production process. Adaptive laboratory evolution (ALE) is a powerful tool to force metabolic adaptations endowing tolerance to stressful environmental conditions, generating superior phenotypes with industrial relevance. Results Y. lipolytica MUCL 28849 underwent ALE in a synthetic medium with increasing concentration of pure or crude glycerol as a stressing factor (9–20% v/v) for 520 generations. In one case of pure glycerol, chemical mutagenesis with ethyl methanesulfonate (EMS) was applied prior to ALE. Growth profile, biomass production and lipid content of 660 evolved strains (EVS), revealed 5 superior isolates; exhibiting from 1.9 to 3.6-fold increase of dry biomass and from 1.1 to 1.6-fold increase of lipid concentration compared to the parental strain, when grown in 15% v/v crude glycerol. NGS for differential gene expression analysis, showed induced expression in all EVS affecting nucleosomal structure and regulation of transcription. As strains differentiated, further changes accumulated in membrane transport and protein transport processes. Genes involved in glycerol catabolism and triacylglycerol biosynthesis were overexpressed in two EVS. Mismatches and gaps in the expressed sequences identified altered splicing and mutations in the EVS, with most of them, affecting different components of septin ring formation in the budding process. The selected YLE155 EVS, used for scale-up cultivation in a 3L benchtop bioreactor with 20% v/v crude glycerol, achieved extended exponential phase, twofold increase of dry biomass and lipid yields at 48 h, while citric acid secretion and glycerol consumption rates were 40% and 50% lower, respectively, compared to the parental strain, after 24 h of cultivation. Conclusion ALE and EMS-ALE under increasing concentrations of pure or crude glycerol generated novel Y. lipolytica strains with enhanced biomass and lipid content. Differential gene expression analysis and scale-up of YLE155, illustrated the potential of the evolved strains to serve as suitable “chassis” for rational engineering approaches towards both increased lipid accumulation, and production of high-added value compounds, through efficient utilization of crude glycerol.

The objective of the present study was to investigate the viscoelastic properties in synovial fluid be-tween normal horses and horses with naturally occurring OA and to detect factors affecting synovial fluid viscosity. In total, 105 horses were included in this study. Synovial fluid samples were obtained from 60 mature horses with mild to moderate osteoarthritis in the 2nd interphalangeal, the metacarpophalangeal or the intercarpal joint. Forty-five horses were used as controls. Full rheological sample characterization was performed in order to measure the elastic G' and viscous G" moduli. For determining hyaluronic acid concentrations a commercially available ELISA kit was used. The results of the linear mixed effect (LME) model revealed statistically significant (p < 0.001) effect of HA concentration, on the mean values of logG' and logG" measurements. The ANOVA findings of the final model revealed statistically significant effect of joint type (p < 0.001) on the mean values of viscoelastic measurements. Interpreting the coefficients of the covariates osteoarthritis (p < 0.001) and age (p = 0.013), a negative correlation was detected on the response logG' and logG" measurements. Geldings seemed to present lower viscous properties compared to mares. To the authors' knowledge this is the first multivariate study to quantitatively evaluate the several factors that affect the viscoelastic properties of equine synovial fluid. Horses with osteoarthritis seemed to present lower viscoelastic prop-erties compared to the healthy subjects that are joint type dependant. Finally, considering the multifactorial nature of osteoarthritis, one should expect an emerging need of personalized disease-modifying treatments.

Objective: The viscoelastic properties of synovial fluid are crucial to joint performance. The objective of the present study was to evaluate qualitatively and quantitatively the viscoelastic properties of equine synovial fluid from normal joints and joints with osteoarthritis and to detect any possible differences. Methodology: Synovial fluid was aspirated from 16 joints with osteoarthritis in a fetlock joint, obtained from 12 mature English Thoroughbred horses. Additionally, synovial fluid samples obtained from 6 normal joints were used as controls. Full rheological characterization was performed in order to measure the elastic G’ and viscous G’’ moduli. Hyaluronic acid (HA) concentration was determined using a commercially available ELISA kit. Results: Viscoelastic properties of osteoarthritic joints were significantly lower compared to the ones obtained from normal joints. Joints with osteoarthritis presented lower HA concentration compared to normal joints (p < 0.001). In addition, a negative correlation between viscoelastic properties and osteoarthritis (lameness score and radiographic score) (p < 0.001) was detected. Conclusion: Osteoarthritic joints present significantly lower viscoelastic properties and lower HA concentrations compared to normal ones. Despite considerable research, the complex role of synovial fluid as a lubricant is not fully understood. Confronting the need of developing new methods to control osteoarthritis, the horse provides an excellent animal model for tentative biomedical extrapolations.

Silver nanoparticles (AgNPs) constitute a promising approach for the development of new antimicrobial systems. The major global concern about the emergence of bacterial strains resistant to widely used therapeutic agents for human infections has increased research for the discovery of new antimicrobial compounds as therapeutic alternatives. The aim of the present study was a preliminary investigation of the spectroscopic properties and inhibitory activity of silver nanoparticles on four reference gram negative and gram positive bacterial strains: Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes and Staphylococcus aureus, at two different concentrations (103 and 106 cfu/ml) using cultivation media. The results confirmed that AgNPs absorb light in the visible area of the electromagnetic spectrum, as a fairly dominant and sharp peak appears at around 425 nm wavelength. These nanomaterials are shown here to be very effective antibacterial agents in both pathogen (Listeria, Salmonella) and non-pathogens (E.coli, Staphylococcus) microorganisms; furthermore the present study proves their efficacy against both Gram positive (Staphylococcus, Listeria) and Gram negative (E.coli, Salmonella) bacteria.