Journal of Materials Chemistry B最新文献

From the Spanish flu to the COVID-19 pandemic, respiratory viruses have inflicted significant damage on the global population. As research into these viruses progresses, so too does the methodology employed. Although traditional in vitro two-dimensional (2D) cell culture techniques and animal models have played crucial roles in our understanding of respiratory viruses and have made significant contributions to research on viral infection mechanisms, as well as the development of drugs and vaccines, they have limitations. Specifically, 2D cell culture models do not accurately simulate the in vivo micro-environment, and animal models may not share the same susceptibility and immune response as humans. Consequently, viral isolation and culture techniques are transitioning towards 3D cell culture technologies. Furthermore, the potential for multi-disciplinary collaborations using 3D cell culture opens new opportunities for personalized medicine. This review will explore the advancement and application of 3D cell culture in respiratory virus research, emphasising the most recent developments and trends in the field. By evaluating the current strengths and limitations of these technologies, we aim to provide insights that will inform future scientific exploration and clinical applications.

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Healing of large skin wounds involves a complex biological process with overlapping phases, facing challenges from fibroblast proliferation, immune response, and extracellular matrix (ECM) remolding. Hydrogel dressings serve as temporary barriers protecting injured tissue from exogenous infections while providing an advantageous microenvironment for cellular regeneration. However, traditionally molded hydrogels through catalyzed or triggered crosslinking into fixed size and strength prior to treatment struggle to integrate tightly with irregular wound surfaces, leading to dressing detachment and wound exposure in areas with high curvature and mobility. Here, we designed CGRGDGC peptide enantiomers, incorporating with 4 arm-PEG-maleimide, to in situ form functional and morphologically matching dual-phasic hydrogel dressing. In situ elastic hydrogel dressing forms within 10 min after applying, with a storage modulus of 1300 Pa and internal porous networks. The peptide incorporation increased the surface potential to ∼370 mV, twice that of PEG hydrogels. The bioactive L-peptide hydrogel exhibited strongest immunomodulation and skin regeneration enhancement, while the non-bioactive D-peptide hydrogel also showed significant promotion compared to the PEG hydrogel. We demonstrated that both the charge microenvironment and bioactivity of hydrogel dressing regulate the immune response and promote wound healing after skin injury. This research provides novel insights and strategies showing that non-ligand peptide sequences achieve biological functions by modulating molecular potential and that adjusting the charge microenvironment and incorporating bioactive peptides through peptide phase introduction enhance skin regeneration.

Osteoarthritis (OA) is a degenerative bone and joint disease characterized by cartilage degradation and an inflammatory environment. Consequently, strategies aimed at remodeling the damaged joint microenvironment by concurrently enhancing lubrication and alleviating inflammation are essential for improving therapeutic efficacy. Herein, we designed multifunctional cyclic brush polymer (CP) nanomicelles composed of surface-grafted zwitterionic poly(sulfobetaine methacrylate) (PSBMA) brushes and a hydrophobic core of PHEMA. Benefiting from the unique cyclic brush topology and hydrated lubrication properties of PSBMA, the CPs exhibited effective lubrication. Tribological and wear tests showcased the CPs significantly reduced the coefficient of friction and surface wear under shear forces. Furthermore, the CPs served as nanocarriers for encapsulating the anti-inflammatory drug resveratrol (RSV) through hydrophobic interactions, serving as drug-loaded nanomicelles CP@RSV. In vitro studies indicated that CP@RSV exhibited excellent cytocompatibility, effectively eliminated reactive oxygen species (ROS) in cells and reversed mitochondrial dysfunction, thereby modulating the oxidative stress microenvironment. In conclusion, CP@RSV integrates enhanced lubrication with antioxidation properties, representing a promising strategy for the treatment of OA.

Polymeric nanoparticles are extremely valuable carriers for drug/gene delivery to treat cancer, as they can protect different therapeutic agents during blood circulation while being able to deliver them at desired locations. Owing to the versatility of polymers, it is possible to fine-tune the performance of nanocarriers by changing different properties, such as chemical structure, architecture, composition and molecular weight or even by functionalising the polymers with targeting molecules. The use of pH-sensitive polymers is a very popular strategy to prepare smart carriers, taking advantage of the acidic intratumoural environment to induce hydrophobic/hydrophilic transitions that allow fast and efficient release of small drugs or genetic material. This review summarizes the contributions of the use of promising pH-sensitive poly(2-(diisopropylamino)ethyl methacrylate) (PDPA), with pK_a around 6.2, in the preparation of nanocarriers for the treatment of different types of cancer through gene therapy, drug delivery or photodynamic therapy. Interest in PDPA-based copolymers for biomedical applications is increasing, as different studies have reported successful encapsulation and delivery of different therapeutic molecules with PDPA-based smart nanocarriers. In vivo studies have shown that tumour growth can be suppressed, revealing the potential of new cancer therapies.

Atherosclerosis (AS) has emerged as a significant worldwide health challenge, necessitating the development of a drug-loading platform to achieve precise delivery of anti-AS therapeutics to lesion sites, thereby mitigating its impact. Given the mildly acidic microenvironment and the abundance of activated macrophages overexpressing scavenger receptor class A (SR-A) at AS lesions, we fabricated a pH-responsive, SR-A-targeting multifunctional drug-loading platform (dextran sulfate–heparin/amorphous calcium phosphate, DS–HEP/ACP) via the coprecipitation method. This design enables efficient delivery of the platform to AS plaques with minimal drug loss during systemic circulation. In this study, we characterized the fundamental properties and biological performance of the synthesized DS–HEP/ACP platform and evaluated the anti-AS efficacy of the atorvastatin calcium (AT)-loaded DS–HEP/ACP@AT system in vitro. In vitro drug release results demonstrated that the platform exhibited superior controlled drug release properties, prolonged drug circulation under physiological conditions, while releasing the drug in the weakly acidic microenvironment of AS. Cellular uptake experiments revealed that the modification of the carrier with DS enabled the drug-loading platform to demonstrate efficient uptake through SR-A receptor-specific mechanisms in stimulated macrophages, achieved via specific receptor-mediated targeting strategies. In anti-AS evaluations, the DS–HEP/ACP@AT system demonstrated anti-inflammatory and lipid-lowering effects in vitro, outperforming monotherapy by combining AT-driven lipid reduction with the platform's intrinsic ability to block phagocytosis of oxidized low-density lipoprotein (Ox-LDL) by macrophages. This dual-targeting AS drug-loading platform achieved precise drug delivery, controlled drug release, and enhanced anti-AS efficacy. In summary, our study validates the DS–HEP/ACP@AT system as a promising candidate for AS therapy.

The spirolactam on/off switch attached to rhodamine dye is known to be a highly selective and sensitive fluorescent probe, yet few studies have explored extending the π-conjugation system within its skeleton for pH detection in live cells. An extended π-conjugated rhodamine section should enable ratiometric pH detection in the near-infrared region. In this study, we synthesized probes A and B by coupling a rhodamine derivative with 7-nitrobenzofurazan and 7-(diethylamino)-2-oxo-3,8a-dihydro-2H-chromene-3-carbaldehyde sections, respectively. Probe A exhibits emission via a Förster resonance energy transfer (FRET) mechanism. Under excitation at 370 nm, the conjugated 7-nitrobenzofurazan in probe A exhibits fluorescence at 465 nm in the ring-closed state, while fluorescence at 660 nm appears in the ring-open state due to increased conjugation in the rhodamine moiety. Excitation of probe B at 325 nm resulted in reduced emission around 350 nm and a significantly enhanced response at 525 nm. Probe A was evaluated for mitochondrial pH detection through ratiometric fluorescence emission measurements. Additional tests in living HeLa cells, including responses to stimuli such as carbonyl cyanide-4(trifluoromethoxy)phenylhydrazone (FCCP), hydrogen peroxide (H₂O₂), N-acetyl cysteine (NAC), mitophagy induced by nutrient deprivation, and hypoxia triggered by cobalt chloride (CoCl₂) treatment, as well as pH changes in fruit fly larvae, further validated its applicability for ratiometric measurement of mitochondrial pH variations. Probe A's emission was dependent on the pH level under basic conditions, but under acidic conditions, the change in conformation upon ring opening resulted in the emission also being affected by viscosity.

Lung cancer is a prevalent and deadly malignancy worldwide. Traditional angiogenesis has been augmented by the discovery of vascular mimicry (VM), an alternative mechanism where tumor cells form vascular-like structures that contribute to tumor aggressiveness independent of endothelial vessels. The study of VM has been constrained by limitations in existing in vitro models, particularly conventional tissue culture-treated plates, which fail to fully replicate the complex tumor microenvironment. Existing biomimetic models are yet to effectively reproduce VM signatures specific to non-small cell lung cancer (NSCLC), hindering further research and therapeutic development. In this context, our research aimed to address these challenges by exploring collagen/fibronectin biological macromolecules as novel biomimetic environments to study VM in NSCLC. Here, we created a collagen/fibronectin-based engineered tumor model both in vivo and in vitro to explore how these matrices affect cellular behaviors, including proliferation, colony formation, migration, stemness, and VM formation. Using extensive gene expression profiling, we characterized NSCLC cells grown in these matrices to identify key genes influencing VM formation. Furthermore, we selected two reported anti-tumor drugs and their potential VM inhibitory effects and verified the practical application of this model by developing a VM-rich tumor model in vivo. Our findings underscore the pivotal role of ECM components, particularly collagen and fibronectin, in modulating critical biological processes in cancer and VM formation. In addition, the two antitumor agents we selected have the potential to inhibit VM occurrence. By simulating the ECM environment conducive to VM, we developed a VM-rich tumor model, and our study provided insights into potential mechanisms underlying VM formation and its regulation in NSCLC.

Metal–organic frameworks (MOFs) have traditionally been valued for their stability, which is crucial for applications in catalysis, separation, and storage. However, instability, often considered a drawback, can serve as a functional advantage in specific applications. This study explores the benefits of unstable MOFs, particularly in areas where controlled degradation is desirable. Instability is an inherent characteristic of many MOFs, and rather than being viewed as a limitation, it can be harnessed to achieve remarkable outcomes. Sacrificial MOFs, which undergo complete or partial decomposition, present unique opportunities in biomedical applications, including drug delivery, bio-imaging, and wound healing, where structural breakdown can be advantageous. Furthermore, instability can be strategically utilized to create temporary scaffolds, controlled-release systems, and transient functional materials. By shifting the perspective from stability as a prerequisite to instability as an asset, this review highlights and underscores the high potential of labile MOFs and their emerging role in diverse fields beyond conventional applications. Therefore, it's critical to learn about potential future uses for sacrificial MOFs, and it's particularly opportune to offer a review in this field. Herein, we provide a description of all applications and characterization in sacrificial MOFs with recent examples and a full discussion about sacrificial MOFs.

The proliferation of pathogenic bacteria and biofilm formation on implantable material surfaces causes negative results in many medical treatments and infections. Despite the measures taken against unwanted bacteria with modern and advanced sterilization, infections due to contamination during the storage of implants are still an important problem. In order to overcome these problems, it has become necessary to develop synergistic systems to increase antibacterial performance and prevent biofilm formation. Polymer brush systems are among the strategies that can prevent bacteria and biofilm formation by keeping cell–surface or bacteria–surface interactions to a minimum. In this study, temperature-sensitive poly (di(ethylene glycol)methyl ether methacrylate) (PDEGMA) brush systems were synthesized on implant surfaces using the photoinduced-electron transfer reversible addition dissociation chain transfer polymerization (PET-RAFT) technique. Vancomycin (Van) antibiotic conjugation was achieved by covalently binding PDEGMA brushes to the carboxylic acid functional end groups. At the same time, Van release studies were performed in this system by utilizing the temperature-sensitive feature of PDEGMA. Antibacterial properties were determined after examining the implant–bacteria interaction for both cases. In particular, such synergistic systems will shed important light on implant studies for researchers thanks to their antibacterial capacities.