Research Progress on Ti3C2Tx-Based Composite Materials in Antibacterial Field.

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area.

Progress in Surface Modification of Titanium Implants by Hydrogel Coatings.

Although titanium and titanium alloys have become the preferred materials for various medical implants, surface modification technology still needs to be strengthened in order to adapt to the complex physiological environment of the human body. Compared with physical or chemical modification methods, biochemical modification, such as the introduction of functional hydrogel coating on implants, can fix biomolecules such as proteins, peptides, growth factors, polysaccharides, or nucleotides on the surface of the implants, so that they can directly participate in biological processes; regulate cell adhesion, proliferation, migration, and differentiation; and improve the biological activity on the surface of the implants. This review begins with a look at common substrate materials for hydrogel coatings on implant surfaces, including natural polymers such as collagen, gelatin, chitosan, and alginate, and synthetic materials such as polyvinyl alcohol, polyacrylamide, polyethylene glycol, and polyacrylic acid. Then, the common construction methods of hydrogel coating (electrochemical method, sol-gel method and layer-by-layer self-assembly method) are introduced. Finally, five aspects of the enhancement effect of hydrogel coating on the surface bioactivity of titanium and titanium alloy implants are described: osseointegration, angiogenesis, macrophage polarization, antibacterial effects, and drug delivery. In this paper, we also summarize the latest research progress and point out the future research direction. After searching, no previous relevant literature reporting this information was found.

Mesoporous Materials Make Hydrogels More Powerful in Biomedicine.

Scientists have been attempting to improve the properties of mesoporous materials and expand their application since the 1990s, and the combination with hydrogels, macromolecular biological materials, is one of the research focuses currently. Uniform mesoporous structure, high specific surface area, good biocompatibility, and biodegradability make the combined use of mesoporous materials more suitable for the sustained release of loaded drugs than single hydrogels. As a joint result, they can achieve tumor targeting, tumor environment stimulation responsiveness, and multiple therapeutic platforms such as photothermal therapy and photodynamic therapy. Due to the photothermal conversion ability, mesoporous materials can significantly improve the antibacterial ability of hydrogels and offer a novel photocatalytic antibacterial mode. In bone repair systems, mesoporous materials remarkably strengthen the mineralization and mechanical properties of hydrogels, aside from being used as drug carriers to load and release various bioactivators to promote osteogenesis. In hemostasis, mesoporous materials greatly elevate the water absorption rate of hydrogels, enhance the mechanical strength of the blood clot, and dramatically shorten the bleeding time. As for wound healing and tissue regeneration, incorporating mesoporous materials can be promising for enhancing vessel formation and cell proliferation of hydrogels. In this paper, we introduce the classification and preparation methods of mesoporous material-loaded composite hydrogels and highlight the applications of composite hydrogels in drug delivery, tumor therapy, antibacterial treatment, osteogenesis, hemostasis, and wound healing. We also summarize the latest research progress and point out future research directions. After searching, no research reporting these contents was found.

Controllable Preparation and Research Progress of Photosensitive Antibacterial Complex Hydrogels.

Hydrogels are materials consisting of a network of hydrophilic polymers. Due to their good biocompatibility and hydrophilicity, they are widely used in biomedicine, food safety, environmental protection, agriculture, and other fields. This paper summarizes the typical complex materials of photocatalysts, photosensitizers, and hydrogels, as week as their antibacterial activities and the basic mechanisms of photothermal and photodynamic effects. In addition, the application of hydrogel-based photoresponsive materials in microbial inactivation is discussed, including the challenges faced in their application. The advantages of photosensitive antibacterial complex hydrogels are highlighted, and their application and research progress in various fields are introduced in detail.

Mesoporous Titanium Dioxide Nanoparticles-Poly(N-isopropylacrylamide) Hydrogel Prepared by Electron Beam Irradiation Inhibits the Proliferation and Migration of Oral Squamous Cell Carcinoma Cells.

An urgently needed approach for the treatment of oral squamous cell carcinoma (OSCC) is the development of novel drug delivery systems that offer targeted specificity and minimal toxic side effects. In this study, we developed an injectable and temperature-sensitive composite hydrogel by combining mesoporous titanium dioxide nanoparticles (MTNs) with Poly(N-isopropylacrylamide) (PNIPAAM) hydrogel to serve as carriers for the model drug Astragalus polysaccharide (APS) using electron beam irradiation. The characteristics of MTNs, including specific surface area and pore size distribution, were analyzed, and the characteristics of MTNs-APS@Hyaluronic acid (HA), such as microscopic morphology, molecular structure, crystal structure, and loading efficiency, were examined. Additionally, the swelling ratio, gel fraction, and microscopic morphology of the composite hydrogel were observed. The in vitro cumulative release curve was plotted to investigate the sustained release of APS in the composite hydrogels. The effects on the proliferation, migration, and mitochondrial membrane potential of CAL-27 cells were evaluated using MTT assay, scratch test, and JC-1 staining. The results indicated successful preparation of MTNs with a specific surface area of 147.059 m2/g and an average pore diameter of 3.256 nm. The composite hydrogel displayed temperature-sensitive and porous characteristics, allowing for slow release of APS. Furthermore, it effectively suppressed CAL-27 cells proliferation, migration, and induced changes in mitochondrial membrane potential. The addition of autophagy inhibitors chloroquine (CQ) and 3-methyladenine (3-MA) attenuated the migration inhibition (p < 0.05).

(-)-Epigallocatechin-3-gallate: a novel storage medium for avulsed teeth.

The purpose of the present study was to evaluate the efficacy of (-)-epigallocatechin-3-gallate (EGCG) in maintaining the vitality of human periodontal ligament (PDL) cells when used as a storage medium for avulsed teeth prior to replantation. Thirty freshly extracted single-rooted human teeth with closed apices were randomly assigned to three experimental groups with 10 samples per group and immersed in one of the storage media: EGCG, Hank's balanced salt solution (HBSS), or milk for 2 h. The PDL cells were dissociated by an enzyme treatment with collagenase and trypsin. The cells were then labeled with 0.4% Trypan blue for the determination of viability. The result showed that EGCG group had the highest percentage of cell viability, followed by HBSS and milk group, in descending order.

Osmanthus-Loaded PVP/PVA Hydrogel Inhibits the Proliferation and Migration of Oral Squamous Cell Carcinoma Cells CAL-27.

Conventional medical agents for oral squamous cell carcinoma (OSCC) with some adverse effects no longer meet the needs of the public. In this study, the prognosis-related hub genes of osmanthus-targeted therapy for OSCC were predicted and analyzed by network pharmacology and molecular docking. Osmanthus was extracted using the ethanol reflux method and osmanthus-loaded PVP/PVA (OF/PVP/PVA) hydrogel was prepared by electron beam radiation. The molecular structure, crystal structure and microscopic morphology of hydrogels were observed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. OSCC cells CAL-27 were cultured with OF/PVP/PVA hydrogel at different concentrations of extract to discover cell proliferation by MTT assay. The scratching test and JC-1 staining were used to observe the migration and mitochondrial membrane potential. Through experimental exploration, we found that a total of six prognosis-related targets were predicted, which are PYGL, AURKA, SQLE, etc., and osmanthus extract had good binding activity to AURKA. In vitro, except for proliferation inhibition, OF/PVP/PVA hydrogel prevented cell migration and changed the mitochondrial membrane potential of CAL-27 cells at a concentration equal to or greater than 50 µg/mL (p < 0.05). The addition of autophagy inhibitor chloroquine and 3-methyladenine weakened the migration inhibition of hydrogel (p < 0.05).

Osmanthus Fragrans Loaded NIPAAM Hydrogel Promotes Osteogenic Differentiation of MC3T3-E1.

There is an urgent need to find long-acting, natural osteogenesis-promoting drug systems. In this study, first the potential targets and mechanism of osmanthus fragrans (O. fragrans) extract in regulating osteogenic differentiation based on autophagy were analyzed by network pharmacology and molecular docking. Then, osmanthus fragrans was extracted using the ethanol reflux method and an osmanthus fragrans extract loaded Poly N-isopropylacrylamide (OF/NIPAAM) hydrogel was prepared by electron beam radiation. The chemical components of the osmanthus fragrans extract and the microstructure of OF/NIPAAM hydrogels were characterized by ultraviolet-visible spectrophotometry (UV-Vis) and X-ray diffraction (XRD), respectively. Mouse embryonic osteoblast precursor cells MC3T3-E1 were cultured with different concentrations of OF/NIPAAM hydrogel to discover cell proliferation activity by CCK-8 assay. Alkaline phosphatase (ALP) staining and alizarin red staining were used to observe the differentiation and calcification. Through experimental exploration, we found that a total of 11 targets were predicted, which are TP53, CASP3, SIRT1, etc., and osmanthus fragrans had good binding activity to TP53. In vitro, except for proliferation promotion, OF/NIPAAM hydrogel enhanced ALP activity and formation of mineralized nodules of MC3T3-E1 cells at a concentration equal to or less than 62.5 µg/mL (p < 0.05). The addition of autophagy inhibitor 3-methyladenine (3-MA) reduced ALP activity and mineralized nodule formation.

A postulated role for human papillomavirus (HPV) in the transformation and proliferation of oral squamous cell carcinoma (OSCC).

Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy and is a major cause of cancer morbidity and mortality worldwide. A strong association of oral cancer with high-risk HPVs infection underlines the importance of the virus in the pathogenesis of these squamous cell carcinomas. We postulate that HPV may contribute to the carcinogenesis of oral epithelial and function to stimulate transformation and proliferation of OSCC. The appropriate method, which may involve immunoprevention, immunotherapy, or immunomodulatory, needs to be developed. Not only humoral immunity, but also cellular immunity must be part of this process.

Inhibition of TLR4 signaling pathway: molecular treatment strategy of periodontitis-associated atherosclerosis.

The accumulation of epidemiologic, pathologic, and animal model studies suggests that periodontal infection may be a contributing risk factor for atherosclerosis. The Toll-like receptor-4 (TLR4) signaling pathway plays an important role in the initiation and progression of periodontitis-associated atherosclerotic disease. We postulate that suppression of TLR4 signaling pathway can be an effective treatment for atherosclerosis. These strategies include prevention of ligand binding to TLR4, blocking the interactions of TLR4s and adaptors in signaling pathways, blocking the enzymes in signaling pathways, and immunostimulation with vaccine adjuvants. However, we should be aware that there may be unknown risks about the new technologies and these drugs, which may cause some unknown side effects in long-term administration.

Advanced glycation end products upregulate the endoplasmic reticulum stress in human periodontal ligament cells.

BACKGROUND: The accumulation of advanced glycation end products (AGEs) appears to be the main factor responsible for modulating periodontal inflammation in diabetes. The aim of this study is to examine the effects of AGEs on inflammation in human periodontal ligament cells and to investigate the mechanism with a specific emphasis on the role of endoplasmic reticulum (ER) stress-induced nuclear factor-kappa B (NF-κB) pathway. METHODS: Cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expressions of ER markers and NF-κB were examined by Western blot analysis. The translocation of NF-κB was observed by immunofluorescence assay. Proinflammatory chemokine production was determined by enzyme-linked immunosorbent assay. RESULTS: Treatment with AGEs reduced cell viability in a concentration- and time-dependent manner. AGEs induced ER stress, as evidenced by survival molecules, such as glucose-regulated protein 78 (GRP78), double-stranded RNA-activated protein kinase-like ER kinase (PERK), and activating transcription factor 6 (ATF-6), and apoptotic molecules, such as CCAAT/enhancer binding protein homologous protein (CHOP) and caspase 12. AGEs upregulated the nucleoprotein expression of NF-κB, enhanced translocation of NF-κB from the cytoplasm to the nucleus, and increased the production of proinflammatory chemokines interleukin-6 and interleukin-8. CONCLUSION: AGEs mediate inflammation of human periodontal ligament cells via the ER stress-induced NF-κB pathway.

Dual Action of Myricetin on Porphyromonas gingivalis and the Inflammatory Response of Host Cells: A Promising Therapeutic Molecule for Periodontal Diseases.

Periodontitis that affects the underlying structures of the periodontium, including the alveolar bone, is a multifactorial disease, whose etiology involves interactions between specific bacterial species of the subgingival biofilm and the host immune components. In the present study, we investigated the effects of myricetin, a flavonol largely distributed in fruits and vegetables, on growth and virulence properties of Porphyromonas gingivalis as well as on the P. gingivalis-induced inflammatory response in host cells. Minimal inhibitory concentration values of myricetin against P. gingivalis were in the range of 62.5 to 125 µg/ml. The iron-chelating activity of myricetin may contribute to the antibacterial activity of this flavonol. Myricetin was found to attenuate the virulence of P. gingivalis by reducing the expression of genes coding for important virulence factors, including proteinases (rgpA, rgpB, and kgp) and adhesins (fimA, hagA, and hagB). Myricetin dose-dependently prevented NF-κB activation in a monocyte model. Moreover, it inhibited the secretion of IL-6, IL-8 and MMP-3 by P. gingivalis-stimulated gingival fibroblasts. In conclusion, our study brought clear evidence that the flavonol myricetin exhibits a dual action on the periodontopathogenic bacterium P. gingivalis and the inflammatory response of host cells. Therefore, myricetin holds promise as a therapeutic agent for the treatment/prevention of periodontitis.

[Pilot study of the effect of green tea extractive epigallocatechin-3-gallate on degradation of collagen in dental erosion].

OBJECTIVE: To observe the effect of green tea extractive epigallocatechin-3-gallate (EGCG) on degradation of collagen in dental erosion. METHODS: Sixty-four volunteers with dental erosion were randomly divided into two groups. The custom fitted trays were made from the heat curable braces and were injected with carboxymethyl cellulose sodium (CMC) hydrogel in one group (control group) or CMC hydrogel with EGCG added in another (experimental group). These trays were used during sleep and removed from oral cavity in the next morning. The content of carboxy-terminal telopeptide of type I collagen (ICTP) were determined by radioimmunoassay kit at 1 d before the experiment, and 1, 2, 3, 4 weeks after the experiment. RESULTS: Both the types and time showed significant effects on ICTP. The incubation in EGCG resulted in relatively rapid and significant (P < 0.05) decrease in the expression level of ICTP compared with the control group. CONCLUSION: EGCG can inhibit collagen degradation and improve the antierosive effect of dentine.