Search Results (1,571)

Lead (Pb²⁺) pollution poses a severe threat to the ecological environment and human health due to its high toxicity, bioaccumulation, and refractory nature. Traditional treatment technologies for lead-contaminated wastewater, such as chemical precipitation, ion exchange, and membrane separation, often face limitations, including secondary pollution, high costs, and high energy consumption. In contrast, adsorption has emerged as a promising alternative technology with advantages such as a simple process, high efficiency at low concentrations, and renewability. Biomass-based hydrogels and their composite systems, as novel green adsorbent materials, combine the abundant functional groups of natural biomass with the structural stability, high porosity, and recoverability of hydrogels through a three-dimensional cross-linked network, offering unique advantages for lead ion adsorption. Depending on their composition, these systems range from fully biodegradable pure biopolymer networks to partly biodegradable or biomass-containing composites incorporating inorganic, carbon-based, or metal–organic framework (MOF) materials. This paper systematically reviews the latest research progress on cellulose, lignin, sodium alginate, chitosan, starch-based hydrogels, and their composite systems for lead (Pb²⁺) adsorption. First, the structural characteristics, cross-linking mechanisms, and functional modification strategies of various biomass hydrogels are introduced. Then, the adsorption mechanisms of Pb²⁺, including multiple modes of action such as coordination complexation, ion exchange, electrostatic interaction, and physical adsorption, are systematically analyzed. The adsorption performance of different material systems is compared in detail. The regeneration and recycling performance, as well as the potential practical applications, of the materials are evaluated. On this basis, the main challenges in current research are summarised: balancing adsorption capacity and mechanical strength, achieving selective adsorption in actual wastewater, improving regeneration efficiency, and optimizing costs. In addition, future development directions for biomass hydrogel adsorbent materials are discussed, including the design of multi-functional composite materials, the development of intelligent, responsive hydrogels, engineering-scale-up, and life-cycle assessment. This review aims to provide a theoretical framework and technical roadmap for the rational design of high-performance, sustainable hydrogel adsorbents and to promote their engineering application for the treatment of lead-contaminated wastewater. Full article

Plant-derived extracellular vesicles (PDEVs) have emerged as promising natural nanocarriers for biomedical applications owing to their distinctive ability to facilitate intercellular communication and transport bioactive molecules. In this review, we employ bibliometric analysis to identify research hotspots and trends, providing a comprehensive overview of these core themes. The bibliometric results reveal a sustained increase in annual publications in this field, with keyword analysis identifying drug delivery, cross-kingdom regulation, immunomodulation, engineering modification, and gut microbiota as five major research themes. The focus of research has evolved from early basic biological characteristics into engineered smart delivery platforms, with the application areas expanding from intestinal inflammation to neurological, metabolic, dermatological, and oncological diseases. This review systematically examines the core directions in this field. It compares the strengths and limitations of mainstream isolation methods and highlights the value of multi-omics integration, covering the molecular mechanisms of ferroptosis and gut microbiota regulation by PDEVs along with engineering strategies such as drug loading, surface modification, and membrane fusion. It also discusses the latest progress in frontier therapeutic applications of PDEVs, including cancer, inflammatory diseases, tissue regeneration and aesthetics, and neurological disorders. Finally, this review summarizes the key challenges confronting the field, including the lack of standardized protocols, production bottlenecks, and engineering obstacles. It also delineates future directions, including establishing international standardization definitions, advancing multi-omics and AI-driven mechanistic elucidation, developing scalable and efficient purification technologies, and executing systematic preclinical safety and pharmacokinetic evaluations to facilitate clinical translation. Full article

Thermochemical conversion of nitrogen- and sulfur-rich biomass-derived wastes, such as sewage sludge, algae, and agricultural residues, is a promising route for renewable fuel production and waste valorization. However, fuel-bound nitrogen can be released as NH₃, HCN, and HNCO, while sulfur species such as H₂S, SO₂, and COS accelerate catalyst deactivation and generate NO_x/SO_x precursors. Metal-loaded ZSM-5 catalysts are attractive for clean catalytic pyrolysis because they combine the MFI pore confinement and tunable Brønsted/Lewis acidity of ZSM-5 with the hydrogen transfer, dehydrogenation, cracking, redox, and sulfur-tolerance functions of metal species. This review critically summarizes recent advances in metal-loaded ZSM-5 catalysts for catalytic denitrogenation of biomass-derived solid wastes. The formation and migration of NH₃, HCN, HNCO, tar-N, and char-N are first discussed to clarify the chemical basis of fuel-N conversion. The effects of ZSM-5 pore structure, acid-site distribution, Si/Al ratio, hierarchical porosity, and synergy on adsorption, diffusion, C-N bond cleavage, heterocyclic-N ring-opening, aromatization, and nitrogen redistribution are then analyzed. Catalyst deactivation under realistic pyrolysis atmospheres is also highlighted, including coke deposition, metal sintering, framework dealumination, mineral poisoning, and H₂S/SO₂/COS-induced sulfur poisoning. Finally, future directions are proposed for designing multifunctional ZSM-5-based catalysts integrating denitrogenation activity, sulfur resistance, coke resistance, regenerability, and quantitative nitrogen/sulfur mass balance. Full article

Based on the growing use of guided bone regeneration (GBR) for implant rehabilitation in atrophic alveolar ridges, the choice of barrier membrane remains a critical factor for clinical success. This review aimed to evaluate the clinical effectiveness of titanium-reinforced dense polytetrafluoroethylene (d-PTFE-Ti) membranes compared with resorbable collagen membranes in vertical ridge augmentation. A literature review was conducted using PubMed, Cochrane Library, and ScienceDirect databases. Clinical studies published since 2014 involving human subjects undergoing GBR procedures with either d-PTFE-Ti or collagen membranes were included. Nine studies met the inclusion criteria, including randomized clinical trials and cohort studies. The selected studies indicated that both membrane-based approaches were effective in promoting bone regeneration and enabling implant placement. Titanium-reinforced d-PTFE membranes may offer mechanical advantages in space maintenance and dimensional stability, particularly in larger vertical defects; however, the available comparative evidence did not demonstrate a consistent statistically significant superiority over collagen-based approaches. Within the limitations of the available evidence, both strategies appear to provide clinically predictable outcomes, and membrane selection should be individualized according to defect morphology and treatment requirements. Full article

Chronic wounds constitute a major clinical and socioeconomic burden owing to prolonged inflammation, persistent bacterial infection, impaired angiogenesis, and defective extracellular matrix remodeling. Advanced wound dressings have traditionally been developed to promote tissue regeneration, control bacterial infection, and restore the wound microenvironment. Recent advances have focused on multifunctional biomaterials integrating regenerative, antibacterial, anti-inflammatory, antioxidant, and controlled drug-delivery properties. Within this context, antiviral biointerface engineering has emerged as a promising, although still exploratory, materials-engineering perspective rather than an established function of wound dressings. Hydrogel–metal–organic framework (MOF) hybrid polymer composites have emerged as versatile platforms for multifunctional wound dressings. Hydrogels provide hydrated three-dimensional matrices with tunable porosity, swelling behavior, mechanical compliance, and biocompatibility, whereas MOFs contribute high surface area, adjustable pore architectures, chemically tailorable active sites, and controlled ion release. Their integration generates synergistic systems whose performance is governed by structure–function relationships involving polymer crosslinking density, MOF dispersion, pore hierarchy, interfacial adhesion, swelling dynamics, and surface functionalization. Collectively, these parameters regulate mass transport, mechanical stability, therapeutic delivery, and cytocompatibility while potentially influencing virus–material interactions through engineered biointerfaces. Current evidence indicates that direct experimental demonstrations of antiviral performance in hydrogel–MOF wound dressing systems remain limited. Accordingly, antiviral biointerface functions should be regarded as emerging engineering opportunities requiring further experimental validation before clinical translation. This review critically analyzes the structure–function engineering principles governing hydrogel–MOF hybrid systems and examines how established regenerative functions may be integrated with emerging antiviral biointerface concepts. Unlike previous reviews focused primarily on drug delivery, antibacterial activity, or tissue engineering, this review emphasizes the relationships between polymer architecture, MOF chemistry, interfacial design, and transport phenomena while explicitly distinguishing experimentally supported evidence from prospective mechanistic concepts. Particular attention is given to current limitations, translational challenges, and future directions for the rational design of next-generation multifunctional hydrogel–MOF wound dressings. Full article

Hyaluronic acid (HA) is a glycosaminoglycan that is found within the body and has both structural and signaling functions in the extracellular matrix. HA is biocompatible and biodegradable; it has a high water content and binds directly to certain cell-surface proteins. Due to these characteristics, it is considered a promising component for the design of biomaterials for regenerative wound healing. This review covers the most recent findings on the use of HA-based biomaterials in soft tissue repair, while also incorporating earlier, foundational studies relevant to the field, focusing on HA’s characteristics, cellular interactions, design, and preclinical and clinical results. The physicochemical characteristics of HA and their influence on cellular responses and tissue regeneration are discussed to show how material properties can be adjusted for specific therapeutic purposes. There have been great advances in chemically modified composite scaffolds and HA matrices, which offer better mechanical stability and controlled degradation. At the same time, new delivery systems have been built using HA, from nanoparticles to gene delivery platforms and growth factors, and these have given the material an active role as a therapeutic agent rather than just a passive one. This narrative review covers the clinical evidence for the effectiveness of commercial products for acute and diabetic wounds, as well as burns and chronic wounds, and discusses where their use is indicated. In the end, the current limitations of the research and future applications and directions are discussed. Full article

The pathogenesis of knee osteoarthritis (KOA) involves bone homeostasis imbalance induced by inflammation, metabolism, age, mechanical stress, joint injury and other factors. Recently, Type H vessels (CD31^hiEMCN^hi endothelial cells) have emerged as a specialized endothelial cell subset that couples angiogenesis with osteogenesis. Type H angiogenesis in the diaphysis was found to be beneficial for maintaining bone homeostasis, while the abnormal proliferation of type H vessels in subchondral bone can lead to chondrocyte hypertrophy and osteophyte formation. However, the mechanism by which the abnormal proliferation of type H vessels induces KOA has not been elucidated in detail. In this review, we summarize the latest evidence on the role of type H endothelial cell function in the pathogenesis and progression of osteoarthritis (OA). We review the role of type H angiogenesis at different sites in the development and progression of OA and focus on the potential mechanisms that regulate type H angiogenesis in OA and the potential therapeutic value and significance of targeting type H angiogenesis in promoting bone regeneration and maintaining bone homeostasis. Finally, we discuss key obstacles and future directions for studying type H vessel regulation in KOA, offering an endothelial cell-based framework for understanding bone homeostasis and improving OA. Full article

Classically, Hedgehog (Hh)/GLI signaling is recognized as a developmental pathway. Increasing evidence indicates that it also contributes to cellular metabolism and adaptation to stress. In this review, we examine the involvement of Hh/GLI signaling in mitochondrial function and redox homeostasis. Mitochondria are major sources of reactive oxygen species (ROS), which act as signaling molecules in cellular adaptation. Hh signaling both influences and responds to ROS production: GLI activity is regulated by redox-dependent mechanisms, and Hh signaling is associated with mitochondrial bioenergetics, dynamics and quality-control pathways. These interactions may contribute to metabolic adaptation in physiological and pathological settings. We also discuss the contribution of sterol metabolism to this regulatory network. Cholesterol and oxysterols modulate Smoothened activation, linking lipid metabolism to mitochondrial function and redox balance. NRF2-dependent antioxidant pathways maintain mitochondrial redox homeostasis, although direct mechanistic crosstalk with Hh/GLI signaling remains incompletely defined. At the tissue level, Hh signaling is involved in responses to irradiation, inflammation, fibrosis, aging and regeneration. Depending on the biological context, pathway activation may support adaptive responses or contribute to tissue dysfunction. Overall, current evidence supports a role for Hh/GLI signaling in mitochondrial redox adaptation through the integration of metabolic and oxidative signals. Full article

Modulating the immune microenvironment has become an emerging strategy for promoting functional bone regeneration, identifying key therapeutic targets remains challenging. Our previous work showed that Nucleotide-binding oligomerization domain-like receptor family caspase recruitment domain containing protein 5 (NLRC5) is involved in bone destruction associated with periodontitis, but its potential and mechanism in regulating bone tissue repair and regeneration have not been fully elucidated. A monocortical bone defect model was established in the mouse femur to assess the impact of NLRC5 on in situ bone healing and regeneration. Mouse bone marrow-derived mesenchymal stem cells (BMSCs) were isolated to evaluate the effects of NLRC5 on osteogenic differentiation, proliferation, and migration. RNA sequencing was used to explore the direct regulatory mechanism of NLRC5 on osteogenic differentiation of mouse BMSCs. Mass cytometry was employed to examine the effect of NLRC5 on the bone marrow immune microenvironment, followed by in vitro validation experiments. Loss of NLRC5 impaired the healing and regeneration of femoral bone defects in mice, and led to a high inflammatory state in the early stage of healing. The absence of NLRC5 inhibited the osteogenic differentiation ability of BMSCs, and could be restored by NLRC5 overexpression, which was achieved through activation of the phosphatidylinositol 3-kinase/protein kinase B(PI3K/AKT) signaling pathway. Mass cytometry data revealed that NLRC5 may serve as an important factor in maintaining the differentiation and maturation of regulatory T cells (Tregs). By modulating the levels of inflammatory cytokines, NLRC5 further influences the osteogenic differentiation of BMSCs. NLRC5 serves as a key regulator and promising candidate for bone repair. NLRC5 contributes to bone regeneration through a dual mechanism: it promotes BMSCs osteogenic differentiation, at least in part via the PI3K/AKT/β-catenin signaling pathway, and indirectly modulates the local immune microenvironment to facilitate bone repair. Full article

The United Nations 2030 Agenda often employs universalist metrics that overlook situated territorial ontologies. This study analyzes the Reverdece Association in Ráquira, Colombia, where an evolving self-determined peasant-mestizo family has articulated a model of resilience rooted in a Muisca-inspired worldview. Utilizing Participatory Action Research (PAR) and qualitative modeling in ATLAS.ti 26, this research examines how community practices generate functional sustainability outcomes. The findings reveal that the association’s efficiency stems from a “Coherence Framework” that synchronizes Identity (Being), Social Agency (Doing), and an Economy of Rootedness (Having). Central to this operational logic is the community making resource management decisions based on direct, somatic interactions with the landscape—such as evaluating fiber quality or water cycles—rather than relying on abstract market signals. By intentionally prioritizing long-term permanence, the association demonstrates that ecological regeneration is a natural outcome of their daily practices. This study concludes that community-led initiatives are more successful in achieving global sustainability goals than top-down institutional interventions. By recognizing situated epistemologies as valid forms of knowledge, the research suggests that the most resilient approaches to sustainability emerge from a collective commitment to regenerate ecosystems and maintain a dignified life within the territory. This indicates that locally grounded practices can complement and, in some cases, surpass standardized global indicators. Full article

The treatment of refractory wastewater pollutants requires advanced materials capable of synergistic enrichment and destruction. Cellulose-based aerogels, combining biomass sustainability with a porous structure, are a promising platform, yet a quantitative synthesis of this field’s evolution is lacking. This study presents the first bibliometric and visual analysis of 463 publications on cellulose-based aerogels for wastewater treatment. The field shows S-shaped growth, evolving from a Nascent phase to Exponential Growth and now entering Maturation. Social network analysis reveals a China-centered but increasingly international collaboration pattern, while institutional productivity remains fragmented into multiple small research teams. The foundation rests on two synergistic pillars: adsorptive sequestration and catalytic degradation, with research evolving from their parallel development to active fusion. Current frontiers focus on sustainable system engineering, emphasizing process integration, material regeneration, and advanced precursors like cellulose nanofiber. This analysis maps the field’s maturation from material exploration toward integrated catalytic system design, providing a foundational reference and clear directives for future research to address integration challenges. In addition to bibliometric mapping, this review critically discusses treatment functions (adsorption, catalytic oxidation, and integrated pathways) and deployment barriers (regeneration, recyclability, and scale-up feasibility), thereby linking knowledge evolution to practical wastewater-treatment translation. While China contributes the largest publication share in the present dataset, the field is supported by increasing participation from multiple countries and regions. Full article

The mammalian respiratory system stands as a frontline barrier, constantly exposed to environmental insults, balancing defensive immunity with gas exchange. Historically considered sterile, the lung harbors a dynamic, low-biomass microbiome that evolves continuously in response to pulmonary pathologies. Accumulating evidence underscores that respiratory health and structural recovery are not autonomous but are critically integrated with distal microbial systems, especially the intestinal tract, through the gut–lung axis (GLA). This review characterizes the GLA as a bidirectional communication highway fueled by immune pathways, microbial metabolites, and direct microbial translocations. During acute or chronic injuries, such as COVID-19, COPD, asthma, idiopathic pulmonary fibrosis (IPF) and lung cancer, the gut microbiota serves as a remote metabolic “rheostat”. It delivers pivotal signaling molecules, such as short-chain fatty acids (SCFAs) and tryptophan metabolites (indoles), that could shape the local microenvironment in which the respiratory epithelium undergoes functional repair or maladaptive, fibrotic remodeling. Mechanistically, gut-derived butyrate enhances mitochondrial activity in alveolar epithelial cells, while resident progenitors, such as Alveolar Type 2 (AT2) cells, depend on intact mitochondrial fatty acid oxidation for proper regenerative differentiation. Conversely, critical lung illness disrupts this homeostasis via a “pathological circuit,” where severe pulmonary inflammation drives gut permeability, fecal dysbiosis, and the subsequent translocation of pathogen-associated molecular patterns (PAMPs, such as LPS) or gut-associated bacteria back into the pulmonary circulation. This review highlights the systemic nature of lung regeneration, which likely depends heavily on intestinal health through the GLA. Ultimately, leveraging these remote microbial networks through precision postbiotic supplementation, dietary priming, or microbiota transplantation represents a crucial frontier in precision medicine to promote definitive alveolar repair. Full article

Background: Disruption of the corneal epithelial (CE) cell layer is a pathological feature of several ocular disorders including the potentially severe condition, neurotrophic keratitis (NK). The drug, Oxervate™, whose active principle is recombinant human nerve growth factor (NGF), has been shown to promote healing of the corneal epithelial layer in NK. This effect could result from NGF stimulating the repair and regeneration of corneal nerves so that they provide better trophic support for CE healing and general health. Another mechanism of NGF in promoting CE layer healing may be through direct stimulation of the division and migration of CE cells. Fetal bovine serum (FBS) has also been found to promote CE layer healing in experimental studies. Like Oxervate™, FBS contains NGF, but it also contains several other bioactive components including other growth factors. The present study compares the effects of FBS to those of NGF to examine whether the combination of bioactive components in FBS might be more effective than NGF alone in producing corneal wound healing. Methods: CE cells of the HCE-S line were grown in 96-well plates fitted with a silicon plug that occluded a 1 mm circular area in the center of each well. When the cells reached confluence, the plugs were removed, resulting in the cell layers each containing a similar central defect. Different amounts of NGF, FBS, and a combination of the two were then added to each well. The effect of these treatments on the amount of closure of the defect after 24 h was measured and compared. Results: NGF increased the amount of closure of the defect after 24 h. At a concentration of 250 nM, NGF produced a significant, 25 ± 9% increase in closure. No further increase in effect was seen when the NGF concentration was increased to 500 nM. FBS also produced an increase in the closure. At an FBS concentration of 10%, this increase was 118 ± 27%, which was significantly greater than the percentage increase produced by NGF. The addition of both 250 nM NGF and 10% FBS together produced no greater amount of closure than that produced by FBS alone. Conclusions: These findings are consistent with earlier data suggesting that NGF can promote corneal healing through a direct effect on CE cells. They also show that FBS is more effective than NGF alone in producing this effect. Since the therapeutic activity of NGF in NK may be partly mediated through a direct action on corneal epithelial cells, identifying the factors in FBS that promote corneal healing might lead to more effective treatments for NK. Full article

Patients with multiple myeloma (MM) exhibit profound immune dysregulation, predisposing them to severe outcomes following SARS-CoV-2 infection. Current evidence highlights shared immunopathological mechanisms linking MM and COVID-19, with particular emphasis on the interleukin-6 (IL-6) axis as a shared amplifier of inflammation rather than the sole driver of disease. MM is characterized by a baseline pro-inflammatory milieu, in part mediated by IL-6, which is further amplified during SARS-CoV-2 infection, resulting in cytokine escalation, complement activation, coagulopathy, and multi-organ injury. This amplification operates within a broader, redundant network that also includes T-cell exhaustion, NK-cell dysfunction, checkpoint signaling, complement and endothelial injury, and treatment-induced immune defects. This overlap provides a mechanistic basis for the disproportionately high morbidity and mortality observed in this population. Even with advancements in vaccination, antiviral therapy, and clinical practice, patients with MM who exhibit impaired vaccine responses, active disease, or treatment-related immune dysfunction continue to experience considerable vulnerability to COVID-19. In addition, MM patients demonstrate suboptimal vaccine-induced immune responses, contributing to persistent vulnerability to severe and breakthrough infections. Modern MM therapies, including anti-CD38 antibodies, BCMA-directed agents, and bispecific T-cell redirecting antibodies, further reshape antiviral immunity by reducing NK cells, inducing plasma cell aplasia, causing hypogammaglobulinemia, and impairing T-cell function. Emerging treatment approaches targeting this shared pathway have been explored, with a focus on mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs). EVs exhibit multimodal properties, including suppression of pro-inflammatory cytokines, restoration of immune homeostasis, inhibition of viral entry, and promotion of tissue repair and regeneration. Early clinical experience in severe COVID-19 populations suggests a favorable short-term safety profile; reported efficacy, however, derives from small, largely uncontrolled or early-phase studies, and the single randomized trial reporting a mortality benefit did so only in an exploratory post hoc subgroup, with its pre-specified primary endpoint not met. Overall, EVs constitute a biologically plausible but as yet unproven adjunctive strategy that warrants further investigation. Critically, no MM patient has ever been enrolled in an EV trial; current rationale for EV use in MM is therefore extrapolated entirely from non-MM populations, and no MM-specific data exist. Difficulties such as EV heterogeneity, manufacturing variability, uncertain pharmacokinetics, limited targeting efficiency, and potential prothrombotic effects must be resolved before their application in MM-specific clinical settings. Full article

The rapid expansion of lithium-ion battery (LIB) use in electric vehicles and large-scale energy storage systems has intensified the need for sustainable end-of-life management. While most research and industrial efforts have focused on recovering valuable metals, graphite anodes, despite constituting a significant portion of battery mass, remain relatively overlooked. This review evaluates current progress in graphite anode recycling, emphasizing technical challenges, scalability, and economic and geopolitical considerations. Conventional recycling methods, including hydrometallurgical, pyrometallurgical, and direct recycling processes, offer viable routes for material recovery but are often constrained by high energy demands, chemical consumption, and degradation of graphite quality. Regenerated graphite exhibits competitive electrochemical performance, with initial Coulombic efficiencies above 90% and reversible capacities comparable to those of commercial materials. In addition, strategies such as surface modification and defect engineering have proven effective in restoring structural integrity and enhancing cycling stability. Despite these advances, major challenges persist in achieving cost-effective, large-scale implementation and consistent material quality suitable for reuse in battery manufacturing. Given increasing supply risks and rapidly rising global demand for graphite, advancing sustainable recycling technologies has become essential. This review emphasizes the need for integrated technological innovation and supportive policy frameworks to enable the development of a circular economy for graphite. Full article