Metabolomics-based study of chemical compositions in cellulase additives derived from a tobacco-origin Bacillus subtilis and their impact on tobacco sensory attributes.

To enhance the quality of tobacco leaves and optimize the smoking experience, diverse strains of functional bacteria and their associated metabolites have been used in tobacco aging. Exogenous cellulase additives are frequently employed to facilitate the degradation of cellulose and other macromolecular matrices and enhance the quality of the tobacco product. However, little is known about how microbial metabolites present in exogenous enzyme additives affect tobacco quality. In this study, crude cellulase solutions, produced by a tobacco-originating bacterium Bacillus subtilis FX-1 were employed on flue-cured tobacco. The incorporation of cellulase solutions resulted in the reduction of cellulose crystallinity in tobacco and the enhancement of the overall sensory quality of tobacco. Notably, tobacco treated with cellulase obtained from laboratory flask fermentation demonstrated superior scent and flavor attributes in comparison to tobacco treated with enzymes derived from industrial bioreactor fermentation. The targeted and untargeted metabolomic analysis revealed the presence of diverse flavor-related precursors and components in the cellulase additives, encompassing sugars, alcohols, amino acids, organic acids, and others. The majority of these metabolites exhibited significantly higher levels in the flask group compared to the bioreactor group, probably contributing to a pronounced enhancement in the sensory quality of tobacco. Our findings suggest that the utilization of metabolic products derived from B. subtilis FX-1 as additives in flue-cured tobacco holds promise as a viable approach for enhancing sensory attributes, establishing a solid theoretical foundation for the potential development of innovative tobacco aging additives.

Platelet-Drug Conjugates Engineered via One-step Fusion Approach for Metastatic and Postoperative Cancer Treatment.

The exploration of cell-based drug delivery systems for cancer therapy has gained growing attention. Approaches to engineering therapeutic cells with multidrug loading in an effective, safe, and precise manner while preserving their inherent biological properties remain of great interest. Here, we report a strategy to simultaneously load multiple drugs in platelets in a one-step fusion process. We demonstrate doxorubicin (DOX)-encapsulated liposomes conjugated with interleukin-15 (IL-15) could fuse with platelets to achieve both cytoplasmic drug loading and surface cytokine modification with a loading efficiency of over 70 % within minutes. Due to their inherent targeting ability to metastatic cancers and postoperative bleeding sites, the engineered platelets demonstrated a synergistic therapeutic effect to suppress lung metastasis and postoperative recurrence in mouse B16F10 melanoma tumor models.

Three-Dimensional Printed BGS Treat a Large Bone Defect in a Rabbit Model.

This study aimed to evaluate if the 3D printed bioactive glass porous scaffolds (BGS) can improve the reconstruction of the large bone defect. A rabbit model of large bone defects was established by making a 1.0 or 1.5 cm segmental defect in the middle of the femur bone. Then a 1.0 or 1.5 cm BGS was implanted into the bone defect. X-ray imaging showed that in both 1.0 and 1.5 cm groups, the newly formed bone tissue could be observed at 4 weeks after implantation, but a strengthened ossification trend could be observed at different time points. In the 1.0 cm group, a larger number of newly formed bone tissues were observed at 4 weeks, and in the 1.5 group, more newly formed bone tissues were found at 8 weeks. Nevertheless, ossified tissue generation on the BGS mainly completed at 12 weeks after implantation in both groups. The H&E staining revealed that the 3D BGS was easily degraded to form osteoid-like material in vivo, where the neo-ossification gradually occurred from the edge to the center. Immunohistochemical analysis showed that in the 1.0 group, protein expressions of three osteogenesis-related genes- BMP, collagen I and RUNX-2-all peaked at 8 weeks, and then gradually decreased at 12 and 18 weeks. In the 1.5 group, BMP and collagen I peaked at 18 weeks.

Three dimensional printed bioglass/gelatin/alginate composite scaffolds with promoted mechanical strength, biomineralization, cell responses and osteogenesis.

In this study, porous bioglass/gelatin/alginate bone tissue engineering scaffolds were fabricated by three-dimensional printing. The compressive strength and in vitro biomineralization properties of the bioglass-gelatin-alginate scaffolds (BG/Gel/SA scaffolds) were significantly improved with the increase of bioglass content until 30% weight percentage followed by a rapid decline in strength. In addition, the cells attach and spread on the BG/Gel/SA scaffolds surfaces represents good adhesion and biocompatibility. Furthermore, the cells (rat bone marrow mesenchymal stem cells, mBMSCs) proliferation and osteogenic differentiation on the BG/Gel/SA scaffolds were also promoted with the increase of bioglass content. Overall, the adding of bioglass in Gel/SA scaffolds promotes mechanical strength and in vitro osteogenic properties and the 30 BG scaffold (30%wt BG) has potential applications in bone tissue engineering and bone regenerative repair because of good compressive strength, biocompatibility, and in vitro osteogenesis.

Canine retraction and anchorage loss self-ligating versus conventional brackets: a systematic review and meta-analysis.

BACKGROUND: The purpose of this systematic review is to identify and review the orthodontic literature with regards to assessing possible differences in canine retraction rate and the amount of antero-posterior anchorage (AP) loss during maxillary canine retraction, using conventional brackets (CBs) and self-ligating brackets (SLBs). METHODS: An electronic search without time or language restrictions was undertake in September 2014 in the following electronic databases: The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE via OVID, EMBASE via OVID, Web of science. We also searched the reference lists of relevant articles. Quality assessment of the included articles was performed. Two of the authors were responsible for study selection, validity assessment and data extraction. RESULTS: Six studies met the inclusion criteria, including 2 randomized controlled trials and 4 control clinical studies. One was assessed as being at low risk of bias. Five trials were assessed as being at moderate risk of bias. The meta-analysis from 6 eligible studies showed that no statistically significant difference was observed between the 2 groups in the rate of canine retraction and loss of antero-posterior anchorage of the molars. CONCLUSION: There is some evidence from this review that both brackets showed the same rate of canine retraction and loss of antero-posterior anchorage of the molars. The results of the present systematic review should be viewed with caution due to the presence of uncontrolled interpreted factors in the included studies. Further well-designed and conducted randomized controlled trials are required, to facilitate comparisons of the results.

High performance injectable Mg doped bioactive glass bone cement for the regulation of osteogenic immune microenvironment.

Although calcium phosphate has been extensively utilized in orthopedic applications such as spine, limbs, dentistry, and maxillofacial surgery, the lack of osteoinductive properties often hinders its effectiveness in treating bone defects resulting from pathological micro-environment such as tumor surgery, osteoporosis, osteomyelitis, and diabetic. Therefore, a novel bone cement based on magnesium-doped bioactive glass was developed in this study. The moderate release of magnesium ions improved the mechanical properties by controlling the crystal size of hydroxyapatite. Through detailed discussion of element content and heat treatment temperature, it was found that 2Mg-BG-800 was suitable for the construction of bone cement. 2Mg-BG-BC exhibited favorable initial (15 min) and final (30 min) setting time, compressive strength (29.45 MPa), compressive modulus (1851.49 MPa), injectability, and shape-adaptability. Furthermore, Mg-BG-BC demonstrated the ability to enhance the osteogenic differentiation of BMSCs, and induce macrophage polarization towards the M2 phenotype, suggesting its potential for osteoporotic fracture regeneration.

Odontogenic and anti-inflammatory effects of magnesium-doped bioactive glass in vital pulp therapy.

This study aimed to investigate the effects of magnesium-doped bioactive glass (Mg-BG) on the mineralization, odontogenesis, and anti-inflammatory abilities of human dental pulp stem cells (hDPSCs). Mg-BG powders with different Mg concentrations were successfully synthesized via the sol-gel method and evaluated using x-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. Apatite formation was observed on the surfaces of the materials after soaking in simulated body fluid. hDPSCs were cultured with Mg-BG powder extracts in vitro, and no evident cytotoxicity was observed. Mg-BG induced alkaline phosphatase (ALP) expression and mineralization of hDPSCs and upregulated the expression of odontogenic genes, including those encoding dentin sialophosphoprotein, dentin matrix protein 1, ALP, osteocalcin, and runt-related transcription factor 2. Moreover, Mg-BG substantially suppressed the secretion of inflammatory cytokines (interleukin [IL]-4, IL-6, IL-8, and tumor necrosis factor-alpha). Collectively, the results of this study suggest that Mg-BG has excellent in vitro bioactivity and is a potential material for vital pulp therapy of inflamed pulps.

Wearable, Biocompatible, and Dual-Emission Ocular Multisensor Patch for Continuous Profiling of Fluoroquinolone Antibiotics in Tears.

The abuse or misuse of antibiotics in clinical and agricultural settings severely endangers human health and ecosystems, which has raised profound concerns for public health worldwide. Trace detection and reliable discrimination of commonly used fluoroquinolone (FQ) antibiotics and their analogues have consequently become urgent to guide the rational use of antibiotic medicines and deliver efficient treatments for associated diseases. Herein, we report a wearable eye patch integrated with a quadruplex nanosensor chip for noninvasive detection and discrimination of primary FQ antibiotics in tears during routine eyedrop treatment. A set of dual-mode fluorescent nanoprobes of red- or green-emitting CdTe quantum dots integrated with lanthanide ions and a sensitizer, adenosine monophosphate, were constructed to provide an enhanced fluorescence up to 45-fold and nanomolar sensitivity toward major FQs owing to the aggregation-regulated antenna effect. The aggregation-driven, CdTe-Ln(III)-based microfluidic sensor chip is highly specific to FQ antibiotics against other non-FQ counterparts or biomolecular interfering species and is able to accurately discriminate nine types of FQ or non-FQ eyedrop suspensions using linear discriminant analysis. The prototyped wearable sensing detector has proven to be biocompatible and nontoxic to human tissues, which integrates the entire optical imaging modules into a miniaturized, smartphone-based platform for field use and reduces the overall assay time to ∼5 min. The practicability of the wearable eye patch was demonstrated through accurate quantification of antibiotics in a bactericidal event and the continuous profiling of FQ residues in tears after using a typical prescription antibiotic eyedrop. This technology provides a useful supplement to the toolbox for on-site and real-time examination and regulation of inappropriate daily drug use that might potentially lead to long-term antibiotic abuse and has great implications in advancing personal healthcare techniques for the regulation of daily medication therapy.

Extraction and characterization of nanocellulose from cattail leaves: Morphological, microstructural and thermal properties.

Hydrogen peroxide combined with acid treatment demonstrates its respective characteristics for the separation of lignocellulosic biomass. Herein, holocellulose was extracted from Cattail leaves (CL) by a two-step treatment with alkali and hydrogen peroxide-acetic acid (HPAA). Then carboxylated nanocellulose was hydrolyzed with a mixed organic/inorganic acid. The chemical composition of the holocellulose and the physicochemical properties of the separated carboxylated nanocellulose were comparable. Carboxyl groups were introduced on the nanocellulose as a result of the esterification process with citric acid (CA), which endows the nanocellulose with high thermal stability (315-318 °C) and good light transmission (>80 %). Furthermore, morphological analyses revealed that nanocellulose had a spider-web-like structure with diameter between 5 and 20 nm.

miR397 regulates cadmium stress response by coordinating lignin polymerization in the root exodermis in Kandelia obovata.

Secondary lignification of the root exodermis of Kandelia obovata is crucial for its response to adversity such as high salinity and anaerobic environment, and this lignification is also effective in blocking cadmium transport to the roots. However, how the differences in lignification of root exodermis at different developmental stages respond to Cd stress and its regulatory mechanisms have not been revealed. In this study, after analyzing the root structure and cell wall thickness using a Phenom scanning electron microscope as well as measuring cadmium content in the root cell wall, we found that the exodermis of young and mature roots of K. obovata responded to Cd stress through the polymerization of different lignin monomers, forming two different mechanisms: chelation and blocking. Through small RNA sequencing, RLM-5'-RACE and dual luciferase transient expression system, we found that miR397 targets and regulates KoLAC4/17/7 expression. The expression of KoLAC4/17 promoted the accumulation of guaiacyl lignin during lignification and enhanced the binding of cadmium to the cell wall. Meanwhile, KoLAC7 expression promotes the accumulation of syringyl lignin during lignification, which enhances the obstruction of cadmium and improves the tolerance to cadmium. These findings enhance our understanding of the molecular mechanisms underlying the differential lignification of the root exodermis of K. obovata in response to cadmium stress, and provide scientific guidance for the conservation of mangrove forests under heavy metal pollution.

Integrating Bioactive Graded Hydrogel with Radially Aligned Nanofibers to Dynamically Manipulate Wound Healing Process.

Skin wound healing is a complex process that requires appropriate treatment and management. Using a single scaffold to dynamically manipulate angiogenesis, cell migration and proliferation, and tissue reconstruction during skin wound healing is a great challenge. We developed a hybrid scaffold platform that integrates the spatiotemporal delivery of bioactive cues with topographical cues to dynamically manipulate the wound-healing process. The scaffold comprised gelatin methacryloyl hydrogels and electrospun poly(ε-caprolactone)/gelatin nanofibers. The hydrogels had graded cross-linking densities and were loaded with two different functional bioactive peptides. The nanofibers comprised a radially aligned nanofiber array layer and a layer of random fibers. During the early stages of wound healing, the KLTWQELYQLKYKGI peptide, which mimics vascular endothelial growth factor, was released from the inner layer of the hydrogel to accelerate angiogenesis. During the later stages of wound healing, the IKVAVS peptide, which promotes cell migration, synergized with the radially aligned nanofiber membrane to promote cell migration, while the nanofiber membrane also supported further cell proliferation. In an in vivo rat skin wound-healing model, the hybrid scaffold significantly accelerated wound healing and collagen deposition, and the ratio of type I to type III collagen at the wound site resembled that of normal skin. The prepared scaffold dynamically regulated the skin tissue regeneration process in stages to achieve rapid wound repair with clinical application potential, providing a strategy for skin wound repair.

[Growth ability of human dental pulp cells on three bioactive scaffolds].

OBJECTIVE: To investigate the proliferation and differentiation of the human dental pulp cells (hDPCs) on the bioactive scaffolds. METHODS: Primary HDPCs were harvested from impacted third molars of healthy adult individuals (18-25 years of age) by enzyme digestion, expanded and cultured. The cells used for this investigation were the 4 th passage. Immunohistochemical methods were used to verify that the cells were dental pulp cells. The expression of stromal precursor antigen-1 (STRO-1) was determined by flow cytometry. Three different types of scaffolds were used: collagen (COL), collagen / bioglass (COL-BG) and collagen / bioglass / polycaprolactone (COL-BG-PCL). Cell proliferation on the scaffolds was determined using a MTT assay at hour 6, on days 1, 3, 5, 7, 14 and 21. On day 14, the scaffolds were stained with the alkaline phosphatase (ALP) staining kit. RESULTS: The tested cells had STRO-1 positive cells. The proliferation of HDPCs was significantly higher on the COL-BG scaffold and COL-BG-PCL scaffold as compared with COL scaffold (P<0.05). Especially on days 14 and 21, the optical density value of bioglass composite scaffold were 5 times that of the COL scaffold. The ALP positive staining area was observed more extensively on the COL-BG scaffold and COL-BG-PCL scaffold than on the COL scaffold. CONCLUSION: As comparison with the COL scaffold, HDPCs' proliferation and differentiation present more activity on the COL-BG and COL-BG-PCL scaffolds.

Two-stage method of free gingival graft prior to periodontal regenerative surgery for the treatment of intrabony defects with insufficient keratinised tissue width: a study protocol for an open-label randomised controlled trial.

INTRODUCTION: Guided tissue regeneration (GTR) combined with bone grafting for periodontal regenerative surgery has ideal clinical results for intrabony defect. However, some sites of intrabony defects often suffer from insufficient keratinised gingival width, which affects the efficacy and long-term prognosis of periodontal tissue regeneration. Free gingival graft (FGG) is an effective surgical procedure to widen the keratinised gingiva, but there are few clinical studies on FGG prior to GTR combination with bone grafting to improve clinical outcomes. METHODS: This study is an open-label randomised controlled trial. 68 patients with periodontitis with at least one intrabony defect depth with ≥3 mm are recruited and randomly grouped. In the test group, FGG is performed first, followed by GTR and bone grafting 3 months later; while in the control group, only periodontal tissue regenerative procedures are performed. After completion of all procedures, the patients will be recalled at 3 months, 6 months and 12 months and the relevant clinical and radiographic examinations will be carried out and statistical analysis of the data will also be performed. The present research has received approval from the Ethics Committee of Shanghai Stomatological Hospital (No.2022-007) on 4 August 2022. DISCUSSION: Exploring the effectiveness of the two-stage approach of FGG prior to periodontal tissue regenerative surgery for the treatment of keratinised gingival width deficient intrabony defects can provide a high-level evidence-based basis for the formulation of relevant treatment strategies in clinical practice. ETHICS AND DISSEMINATION: The present research has received approval from the Ethics Committee of Shanghai Stomatological Hospital (No.2022-007) on 4 August 2022. The patients will be incorporated into this trial only after their written informed consent has been obtained. The study will be performed according to the 2013 revision of the Helsinki Declaration of 1975. Personal information of all subjects will be stored in the Department of Periodontology of Shanghai Stomatological Hospital. Data of the present research will be registered with the Clinical Trials Registry Platform. Additionally, we will disseminate the results through scientific journals. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ID: ChiCTR 2200063180. Registered on 1 September 2022.

A bioactive glass functional hydrogel enhances bone augmentation via synergistic angiogenesis, self-swelling and osteogenesis.

Bone augmentation materials usually cannot provide enough new bone for dental implants due to the material degradation and mucosal pressure. The use of hydrogels with self-swelling properties may provide a higher bone augmentation, although swelling is generally considered to be a disadvantage in tissue engineering. Herein, a double-crosslinked gelatin-hyaluronic acid hydrogels (GH) with self-swelling properties were utilized. Meanwhile, niobium doped bioactive glasses (NbBG) was dispersed in the hydrogel network to prepare the GH-NbBG hydrogel. The composite hydrogel exhibited excellent biocompatibility and the addition of NbBG significantly improved the mechanical properties of the hydrogel. In vivo results found that GH-NbBG synergistically promoted angiogenesis and increased bone augmentation by self-swelling at the early stage of implantation. In addition, at the late stage after implantation, GH-NbBG significantly promoted new bone formation by activating RUNX2/Bglap signaling pathway. Therefore, this study reverses the self-swelling disadvantage of hydrogels into advantage and provides novel ideas for the application of hydrogels in bone augmentation.

Combined effects of microplastics and antibiotic-resistant bacteria on Daphnia magna growth and expression of functional genes.

Microplastics could act as vectors for the transport of harmful bacteria, such as pathogens and antibiotic resistance bacteria (ARB), but their combined effects have not been reported yet. Here, ARB Shigella flexneri with sulfonamides resistance and micro-polystyrene (micro-PS) were used to investigate their possible combined effects on the growth and expression of functional genes in Daphnia magna. Results showed that micro-PS colonized with S. flexneri were ingested by D. magna and blocked in their intestine after 24 h exposure. Changes were observed in the life history and morphology of D. magna, as well as the expression of functional genes in all treatments, but with no difference in the survival rate. We also determined the expression of six functional genes involved in energy and metabolism (arginine kinase, AK) and oxidative stress response (thioredoxin reductase, TRxR, catalase, CAT, and glutathione S-transferases, GSTs), as well as in growth, development and reproduction (vitellogenin, Vtg1 and ecdysone receptor, EcR). AK and Vtg1 did not show significant differences, however, EcR was down-regulated and the other three genes (TRxR, CAT, GSTs) were up-regulated in the combined-treated group. Antibiotic resistance gene (ARGs) sul1 was detected when exposed to micro-PS colonized with S. flexneri., suggesting that D. magna could acquire resistance genes through microplastic biofilms. These results indicated that MPs could act as a carrier of ARB to transfer ARGs into D. magna, and affect the life history, morphology, and the expression of related functional genes of D. magna, to adapt to the stress caused by MPs and ARB.

Sequential soft- and hard-tissue augmentation after clear aligner-mediated adjustment of traumatic occlusion: A case report.

BACKGROUND: Oral health and esthetic concerns have increasingly motivated adults with periodontitis to seek orthodontic care. Patients with periodontitis often have other dental complications that can make treatment more challenging or less likely to be successful. The predictability of multidisciplinary regenerative and orthodontic treatment approaches in a patient with periodontitis, thin periodontal phenotype, and anterior crossbite is described. CASE DESCRIPTION: A 35-year-old man was designated as having a high risk of experiencing soft-tissue recession owing to his thin periodontal phenotype. After the initial periodontal therapy, clear aligners were used to eliminate the anterior crossbite that was causing traumatic occlusion. In addition, a subepithelial connective tissue graft was used to alter the thin periodontal phenotype. Three months later, guided bone regeneration with corticotomy was performed to increase bone mass, and orthodontic traction was used at 2 weeks after surgery. Orthodontic treatment was continued until all the spaces had been closed. Clinical and radiographic evaluations conducted at the 6-month follow-up revealed substantial improvements in both the soft- and hard-tissue phenotypes. PRACTICAL IMPLICATIONS: Outcomes in this case indicate that sequential soft- and hard-tissue augmentation, after eliminating traumatic occlusion via using a clear aligner, may be a valuable approach for improving soft- and hard-tissue support in patients with periodontitis.

High-Throughput Surface-Enhanced Raman Scattering for Screening Chemical Sensor Candidates Enabled by Bipolar Electrochemistry.

A variety of hydrothermal or electrochemical methods have been explored to prepare noble metal nanostructures as surface-enhanced Raman scattering (SERS) substrates. However, most of those metallic nanoarrays are structurally homogeneous, which makes it laborious to select the high-performance substrates for particular Raman sensing purposes. Here, a high-throughput SERS imaging strategy is demonstrated for the first time for screening chemical sensors with sub-nanomolar sensitivities. Bipolar electrochemistry was applied to generate Au or Au-Ag gradient nanoarrays with diverse chemical compositions, morphologies, and particle dimensions ranging from several nanometers to micrometers. The selected "hot-spots" on the Au-Ag alloy nanoarray exhibited a 660-fold enhancement in SERS intensity compared to those on the pure Au gradient nanoarray. The SERS screening of 4-aminothiophenol, 4-nitrothiophenol, and 4-mercaptobenzoic acid was carried out that provided a limit of detection (LOD) between 1 and 5 pM. The distinctive LODs among three thiophenolic Raman probes are ascribed to the differences in the affinity of the probe to the alloy, orientation of the metal-ligand monolayer, or plasmonic environment of the nanoarray surface. As a continuous, rapid, and cost-effective manner to fabricate transitional nanostructures and screen out SERS responsive sites, this method not only facilitates controllable synthesis of noble metal nanoarrays but has the potential to provide an alternative tool for ultrasensitive chemical sensing on a wide range of bimetallic substrates.

Characteristics of microplastic pollution and analysis of colonized-microbiota in a freshwater aquaculture system.

The microbial communities associated with microplastics (MPs) and their ambient environments have received wide attention. Although previous studies have reported the differences of microbial communities between MPs and natural environment or substrates, the effects of MPs on microbial balance and functions in ambient water remain unclear, particularly for aquaculture water. Here, we investigated the MPs pollution in farm ponds of grass carp located in the Foshan City of Guangdong Province and reported the distinction of bacterial structures, functions, and complexity between microbiota on MPs and in water. MPs with an average abundance of 288.53 ± 74.27 items/L in pond water were mostly fibers and cellulose, mainly transparent and in size of 0.5-1 mm. Structures and functions of bacterial communities on MPs significantly differed from that in pond water. A large number of enriched or depleted OTUs on MPs compared with water belong to the phylum Proteobacteria, the predominant phylum in microbial communities on MPs and in water. Some species included in the phylum Proteobacteria have been shown to be cellulose-degrading and pathogenic. Microbiota on MPs exhibited higher species richness and diversity as well as a more complex network than that in water, illustrating MPs as a distinct habitat in the aquaculture system.

Microplastics as an aquatic pollutant affect gut microbiota within aquatic animals.

The adverse impact of microplastics (MPs) on gut microbiota within aquatic animals depends on the overall effect of chemicals and biofilm of MPs. Thus, it is ideal to fully understand the influences that arise from each or even all of these characteristics, which should give us a whole picture of consequences that are brought by MPs. Harmful effects of MPs on gut microbiota within aquatic organisms start from the ingestion of MPs by aquatic organisms. According to this, the present review will discuss the ingestion of MPs and its following results on gut microbial communities within aquatic animals, in which chemical components, such as plastic polymers, heavy metals and POPs, and the biofilm of MPs would be involved. This review firstly analyzed the impacts of MPs on aquatic organisms in detail about its chemical components and biofilm based on previous relevant studies. At last, the significance of field studies, functional studies and complex dynamics of gut microbial ecology in the future research of MPs affecting gut microbiota is discussed.

Self-Adhesive Hydrogel Biomimetic Periosteum to Promote Critical-Size Bone Defect Repair via Synergistic Osteogenesis and Angiogenesis.

The periosteum plays an important role in the regeneration of critical-size bone defects, with functions of recruiting multiple cells, accelerating vascular network reconstruction, and guiding bone tissue regeneration. However, these functions cannot be easily implemented by simply simulating the periosteum via a material structure design or by loading exogenous cytokines. Herein, inspired by the periosteal function, we propose a biomimetic periosteum preparation strategy to enhance natural polymer hydrogel membranes using inorganic bioactive materials. The biomimetic periosteum having bone tissue self-adhesive functions and resembling an extracellular matrix was prepared using dopamine-modified gelatin and oxidized hyaluronan (GA/HA), and micro/nanobioactive glass (MNBG) was further incorporated into the hydrogel to fabricate an organic/inorganic co-crosslinked hydrogel membrane (GA/HA-BG). The addition of MNBG enhanced the stability of the natural polymer hydrogel membrane, resulting in a sustained degradation time, biomineralization, and long-term release of ions. The Ca2+ and SiO44- ions released by bioactive glass were shown to recruit cells and promote the differentiation of bone marrow stromal cells into osteoblasts, initiating multicentric osteogenic behavior. Additionally, the bioactive ions were able to continuously stimulate the endogenous expression of vascular endothelial growth factor from human umbilical vein endothelial cells through the PI3K/Akt/HIF-1α pathway, which accelerated vascularization of the defect area and synergistically promoted the repair of bone defects. This organic-inorganic biomimetic periosteum has been proved to be effective and versatile in critical-size bone defect repair and is expected to provide a promising strategy for solving clinical issues.