The RGD-binding integrins αvß6 and αvß8 are receptors for mouse adenovirus-1 and -3 infection.

Mammalian adenoviruses (AdVs) comprise more than ~350 types including over 100 human (HAdVs) and just three mouse AdVs (MAdVs). While most HAdVs initiate infection by high affinity/avidity binding of their fiber knob (FK) protein to either coxsackievirus AdV receptor (CAR), CD46 or desmoglein (DSG)-2, MAdV-1 (M1) infection requires arginine-glycine-aspartate (RGD) binding integrins. To identify the receptors mediating MAdV infection we generated five novel reporter viruses for MAdV-1/-2/-3 (M1, M2, M3) transducing permissive murine (m) CMT-93 cells, but not B16 mouse melanoma cells expressing mCAR, human (h) CD46 or hDSG-2. Recombinant M1 or M3 FKs cross-blocked M1 and M3 but not M2 infections. Profiling of murine and human cells expressing RGD-binding integrins suggested that αvß6 and αvß8 heterodimers are associated with M1 and M3 infections. Ectopic expression of mß6 in B16 cells strongly enhanced M1 and M3 binding, infection, and progeny production comparable with mαvß6-positive CMT-93 cells, whereas mß8 expressing cells were more permissive to M1 than M3. Anti-integrin antibodies potently blocked M1 and M3 binding and infection of CMT-93 cells and hαvß8-positive M000216 cells. Soluble integrin αvß6, and synthetic peptides containing the RGDLXXL sequence derived from FK-M1, FK-M3 and foot and mouth disease virus coat protein strongly interfered with M1/M3 infections, in agreement with high affinity interactions of FK-M1/FK-M3 with αvß6/αvß8, determined by surface plasmon resonance measurements. Molecular docking simulations of ternary complexes revealed a bent conformation of RGDLXXL-containing FK-M3 peptides on the subunit interface of αvß6/ß8, where the distal leucine residue dips into a hydrophobic pocket of ß6/8, the arginine residue ionically engages αv aspartate215, and the aspartate residue coordinates a divalent cation in αvß6/ß8. Together, the RGDLXXL-bearing FKs are part of an essential mechanism for M1/M3 infection engaging murine and human αvß6/8 integrins. These integrins are highly conserved in other mammals, and may favour cross-species virus transmission.

Polystyrene microplastic particles induce autophagic cell death in BEAS-2B human bronchial epithelial cells.

The detection of high levels of microplastics in indoor and outdoor air has increased concerns regarding its toxic effects on the respiratory system. They are not easily degradable and can be deposited deep in the lungs. Although several studies have reported inhalation toxicities of microplastics, they are still controversial due to a lack of evidence. Herein, we evaluated the inhalation toxicities of three differently charged polystyrene microplastics (PS-MPs), the most abundant microplastics in the air. Cytotoxicity and ROS generation were evaluated using WST-1 and DCF-DA assays, respectively. To evaluate the toxic effects on the lung, inflammatory responses were analyzed after repeated exposure to the PS-MPs through intratracheal instillation. To explore the mechanism of toxicity, autophagy and ER stress-associated proteins were analyzed. Only the positively charged PS-MPs (NH2 -PS-MPs) showed cytotoxicity and increased ROS generation in BEAS-2B cells. Similarly, only NH2 -PS-MPs significantly increased the expression and secretion of the pro-inflammatory cytokine IL-ß in the animal experiments. The expression of ER stress proteins indicated that NH2 -PS-MPs increased ER stress via PERK-EIF2α and ATF4-CHOP pathways. Moreover, accumulation of NH2 -PS-MPs in lysosomes and deformity of the nucleus were observed in BEAS-2B cells with autophagy induction. Taken together, our results demonstrated that NH2 -PS-MPs induced autophagic cell death in bronchial epithelial cells, leading to inflammatory responses in the lungs. These results suggest that repeated inhalation of microplastics can result in inflammatory responses in the lung through cellular damage of lung epithelial cells, and that inhalation microplastics should be monitored to reduce inhalation health risks.

2D Polymer Nanonets: Controllable Constructions and Functional Applications.

2D polymer nanonets have demonstrated great potential in various application fields due to their integrated advantages of ultrafine diameter, small pore size, high porosity, excellent interconnectivity, and large specific surface area. Here, a comprehensive overview of the controlled constructions of the polymer nanonets derived from electrospinning/netting, direct electronetting, self-assembly of cellulose nanofibers, and nonsolvent-induced phase separation is provided. Then, the widely researched multifunctional applications of polymer nanonets in filtration, sensor, tissue engineering, and electricity are also given. Finally, the challenges and possible directions for further developing the polymer nanonets are also intensively highlighted.

Design of Hierarchically Tailored Hybrids Based on Nickle Nanocrystal-Decorated Manganese Dioxides for Enhanced Fire Safety of Epoxy Resin.

A novel and hierarchical hybrid composite (MnO2@CHS@SA@Ni) was synthesized utilizing manganese dioxide (MnO2) nanosheets as the core structure, self-assembly chitosan (CHS), sodium alginate (SA) and nickel species (Ni) as surface layers, and it was further incorporated into an epoxy matrix for achieving fire hazard suppression via surface self-assembly technology. Herein, the resultant hybrid epoxy composite possessed an exceptional nano-barrier and synergistic charring effect to aid the formation of a compact layered structure that enhanced its fire-resistive effectiveness. As a result, the addition of only 2 wt% MnO2@CHS@SA@Ni hybrids led to a dramatic reduction in the peak heat release rate and total heat release values (by ca. 33% and 27.8%) of the epoxy matrix. Notably, the peak smoke production rate and total smoke production values of EP/MnO2@CHS@SA@Ni 2% were decreased by ca. 16.9 and 38.4% compared to the corresponding data of pristine EP. This was accompanied by the suppression of toxic CO, NO release and the diffusion of thermal pyrolysis gases during combustion through TG-IR results. Overall, a significant fire-testing outcome of the proposed hierarchical structure was proven to be effective for epoxy composites in terms of flammability, smoke and toxicity reductions, optimizing their prospects in other polymeric materials in the respective fields.

Ultrasensitive glucose detection from tears and saliva through integrating a glucose oxidase-coupled DNAzyme and CRISPR-Cas12a.

The accurate and sensitive detection of glucose from secretory clinical samples, such as tears and saliva, remains a great challenge. In this research, a novel ultrasensitive glucose detection method consisting of a glucose oxidase (GOx), pistol-like DNAzyme (PLDz), and CRISPR-Cas12a system is proposed. First, the oxidation of glucose catalyzed by GOx leads to the production of H2O2; the self-cleavage activity of PLDz is activated after recognition of the produced H2O2. The two procedures triggered by COx and PLDz play an important role in accurately identifying glucose and converting glucose signals to nucleic acids. The obtained PLDz fragments can be recognized by the Cas12 enzyme and thus activate the trans-cleavage activity of the Cas12a enzyme. Finally, the surrounding reporter probes are cut by the Cas12a enzyme to produce fluorescence signals. In summary, an ultra-sensitive and specific fluorescence method has been developed for glucose detection from secretory clinical samples, which could potentially contribute to the noninvasive diagnosis of diabetes mellitus.

HA-g-CS Implant and Moderate-intensity Exercise Stimulate Subchondral Bone Remodeling and Promote Repair of Osteochondral Defects in Mice.

Background: Substantial evidence shows that crosstalk between cartilage and subchondral bone may play an important role in cartilage repair. Animal models have shown that hydroxyapatite-grafted-chitosan implant (HA-g-CS) and moderate-intensity exercise promote regeneration of osteochondral defects. However, no in vivo studies have demonstrated that these two factors may have a synergistic activity to facilitate subchondral bone remodeling in mice, thus supporting bone-cartilage repair. Questions: This study was to clarify whether HA-g-CS and moderate-intensity exercise might have a synergistic effect on facilitating (1) regeneration of osteochondral defects and (2) subchondral bone remodeling in a mouse model of osteochondral defects. Methods: Mouse models of osteochondral defects were created and divided into four groups. BC Group was subjected to no treatment, HC Group to HA-g-CS implantation into osteochondral defects, ME group to moderate-intensity treadmill running exercise, and HC+ME group to both HA-g-CS implantation and moderate-intensity exercise until sacrifice. Extent of subchondral bone remodeling at the injury site and subsequent cartilage repair were assessed at 4 weeks after surgery. Results: Compared with BC group, HC, ME and HC+ME groups showed more cartilage repair and thicker articular cartilage layers and HC+ME group acquired the best results. The extent of cartilage repair was correlated positively to bone formation activity at the injured site as verified by microCT and correlation analysis. Histology and immunofluorescence staining confirmed that bone remodeling activity was increased in HC and ME groups, and especially in HC+ME group. This bone formation process was accompanied by an increase in osteogenesis and chondrogenesis factors at the injury site which promoted cartilage repair. Conclusions: In a mouse model of osteochondral repair, HA-g-CS implant and moderate-intensity exercise may have a synergistic effect on improving osteochondral repair potentially through promotion of subchondral bone remodeling and generation of osteogenesis and chondrogenesis factors. Clinical Relevance: Combination of HA-g-CS implantation and moderate-intensity exercise may be considered potentially in clinic to promote osteochondral defect repair. Also, cartilage and subchondral bone forms a functional unit in an articular joint and subchondral bone may regulate cartilage repair by secreting growth factors in its remodeling process. However, a deeper insight into the exact role of HA-g-CS implantation and moderate-intensity exercise in promoting osteochondral repair in other animal models should be explored before they can be applied in clinic in the future.

Asprin-loaded strontium-containing α-calcium sulphate hemihydrate/nano-hydroxyapatite composite promotes regeneration of critical bone defects.

Our laboratory originally synthesized strontium(Sr)-containing α-calcium sulphate hemihydrate/nano-hydroxyapatite composite (Sr-α-CSH/n-HA) and demonstrated its ability to repair critical bone defects. This study attempted to incorporate aspirin into it to produce a better bone graft material for critical bone defects. After 5% Sr-α-CSH was prepared by coprecipitation and hydrothermal methods, it was mixed with aspirin solution of different concentrations (50 µg/ml, 200 µg/ml, 800 µg/ml and 3200 µg/ml) at a fixed liquid-solid ratio (0.54 v/w) to obtain aspirin-loaded Sr-α-CSH/n-HA composite. In vitro experiments were performed on the composite extracts. The tibial defects (3 mm*5 mm) in SD rat model were filled with the composite for 4 weeks and 12 weeks to evaluate its osteogenic capacity in vivo. Our results showed its capability of proliferation, migration and osteogenesis of BMSCs in vitro got improved. In vivo treatment with 800 µg/ml aspirin-loaded Sr-α-CSH/n-HA composite led to significantly more new bone formation in the defects compared with Sr-α-CSH/n-HA composite and significantly promoted the expression of osteogenic-related genes and inhibited osteoclast activity. In general, our research suggests that aspirin-loaded Sr-α-CSH/n-HA composite may have a greater capacity of repairing tibial defects in SD rats than simple Sr-α-CSH/n-HA composite.

Changes in heart rate related to rhythmic masticatory muscle activities and limb movements in patients with sleep bruxism.

Most sleep bruxism (SB) episodes are accompanied by an increase in sympathetic tone and heart rate (HR). To characterise heart rate (HR) changes in relation to rhythmic masticatory muscle activities (RMMAs) in SB patients, polysomnographic recordings were performed on 10 SB patients and 11 normal controls. The duration of movement events, amplitude and duration of HR increases, and time to reach HR peak associated with RMMAs and limb movements (LMs) were determined, and the relationships of the parameters of HR increases with types of movements and RMMAs were analysed. All of the parameters of HR increases associated with three types of movements (RMMAs, RMMAs + LMs and LMs) and masseter activities (phasic, tonic and mixed) were significantly different (two-way ANOVA, P < .001 for all) in both SB patients and controls. The duration of RMMAs/LMs was positively correlated with the parameters (SB patients: R2  = .24-.85, P < .0001; controls: R2  = .23-.68, P < .0001). The amplitude of HR increases was also positively correlated with respiration changes in the SB patients (R2  = .3258, P < .0001) and controls (R2  = .09469, P < .05). The proportions of phasic RMMAs associated with awakenings, microarousals and no cortical arousals were significantly different and so were the proportions of tonic and mixed RMMAs (Friedman's tests, P < .05-.001). The HR increases associated with RMMAs may be intrinsic to the cortical arousal response and autonomic activation, and differences in HR increases associated with different types of movements and RMMAs might be related to the changes in respiration and differences in cortical arousal levels.

Loss of homeoprotein Msx1 and Msx2 leading to athletic and kinematic impairment related to the increasing neural excitability of neurons in aberrant neocortex in mice.

Although homeoproteins Msx1 and Msx2, the cell-specific transcription regulators, have been proven to play multiple roles in the embryogenesis of bone, muscle and tooth, the functions and mechanisms of Msx1 and Msx2 in the development of the central nervous system of mice after birth are not clear because of the death of Msx1 and Msx1/2 germline-deleted embryo at late gestation of mouse. In current research, Nestin-Cre mice was introduced to generate the central nervous system-specific knockout mice (Nestin-Cre;Msx1,Msx2fl/fl). We found that besides the falling of the body mass and the brain volume, the cortical tissue sections and staining showed the decreasing thickness of layer II-IV and declining number of vertebral cells in layer V resulting from Msx1/2 deletion. In addition, electrophysiological tests revealed the aberrant action potential parameters of deep pyramidal neurons in Nestin-Cre;Msx1,2 fl/fl mice, which may be related with the ethology impairment displayed in further experiments. We discovered Nestin-Cre;Msx1,2 fl/fl mice had severe impairment in their athletic ability and kinematic learning ability in rotate test, and exhibited hyperactivity in open-field test. Above all, our results revealed that deletion of homeoproteins Msx1 and Msx2 could lead to behavioral disorders and suggested that Msx1 and Msx2 played a crucial role in regulating the development and function of the neocortex. In addition, our current research provided a new mouse model for understanding the pathogenesis of human central nervous system disease.

Characterisation of the relationships between rhythmic masticatory muscle activities and limb movements in patients with sleep bruxism.

BACKGROUND: Most rhythmic masticatory muscle activities (RMMAs) have been shown to be accompanied with limb movements (LMs) in sleep bruxism (SB) patients during sleep. OBJECTIVES: To compare the relationships between RMMAs and LMs in SB patients and normal subjects. METHODS: Polysomnographic recordings were performed on eight SB patients and nine normal subjects and the frequencies and durations of RMMAs as well as LMs were determined. Linear regression and correlation analysis were performed to study the relationship between durations of RMMAs and LMs when RMMAs occurred with LMs. RESULTS: Most LMs in SB patients, but not in normal subjects, were accompanied with RMMAs. RMMAs in SB patients were more likely to be isolated, phasic or mixed, while RMMAs in normal subjects were more likely to be tonic. The frequencies of LMs, isolated RMMAs and RMMAs accompanied with LMs in SB patients were significantly higher than those in normal subjects. Furthermore, linear regression and correlation analysis showed that duration of RMMAs was significantly associated with that of LMs when RMMAs occurred with LMs. The duration of RMMAs, when accompanied with LMs, in SB patients was significantly longer than that in normal subjects. CONCLUSIONS: Close relationships between LMs and RMMAs exist in SB patients and normal subjects, and SB episodes may be part of cortical arousal responses and the increased cortical activities associated with SB episodes may not just be localised to the central nervous system (CNS) that controls jaw movements but may also include other parts of CNS that controls LMs.

Repair of Osteochondral Defects in a Rabbit Model Using Bilayer Poly(Lactide-co-Glycolide) Scaffolds Loaded with Autologous Platelet-Rich Plasma.

BACKGROUND To examine the effects of the addition of autologous platelet-rich plasma (PRP) into bilayer poly(lactide-co-glycolide) (PLGA) scaffolds on the reconstruction of osteochondral defects in a rabbit model. MATERIAL AND METHODS Porous PLGA scaffolds were prepared in a bilayered manner to reflect the structure of chondral and subchondral bone. Bone defects, measuring 4 mm in diameter and 4 mm in thickness, were created in both knee joints in 18 healthy New Zealand white rabbits, aged between 120-180 days old. Rabbits were randomly divided into three groups: rabbits with bone defects implanted with bilayer PLGA scaffolds (PLGA group) (N=6); or with bilayer PLGA and autologous PRP (PLGA/PRP group) (N=6); and the untreated group (control group) (N=6). The gross morphology, histology, and immunohistochemistry for the expression of collagen type II and aggrecan were observed at 12 weeks after surgery and compared using a scoring system. Micro-computed tomography (CT) imaging and relative expression of specific genes were also assessed. RESULTS The platelet concentrations in the PRP samples were found to be 4.9 times greater than that of whole blood samples. The total score on gross appearance and histology was greatest in the PLGA/PRP group, as was the expression of collagen II and aggrecan of the neo-tissue. Micro-CT imaging showed that more subchondral bone was formed in the PLGA/PRP group. CONCLUSIONS Bilayer PLGA scaffolds loaded with autologous PRP improve the reconstruction of osteochondral defects in the rabbit model.

Materials from Mussel-Inspired Chemistry for Cell and Tissue Engineering Applications.

Current advances in biomaterial fabrication techniques have broadened their application in different realms of biomedical engineering, spanning from drug delivery to tissue engineering. The success of biomaterials depends highly on the ability to modulate cell and tissue responses, including cell adhesion, as well as induction of repair and immune processes. Thus, most recent approaches in the field have concentrated on functionalizing biomaterials with different biomolecules intended to evoke cell- and tissue-specific reactions. Marine mussels produce mussel adhesive proteins (MAPs), which help them strongly attach to different surfaces, even under wet conditions in the ocean. Inspired by mussel adhesiveness, scientists discovered that dopamine undergoes self-polymerization at alkaline conditions. This reaction provides a universal coating for metals, polymers, and ceramics, regardless of their chemical and physical properties. Furthermore, this polymerized layer is enriched with catechol groups that enable immobilization of primary amine or thiol-based biomolecules via a simple dipping process. Herein, this review explores the versatile surface modification techniques that have recently been exploited in tissue engineering and summarizes polydopamine polymerization mechanisms, coating process parameters, and effects on substrate properties. A brief discussion of polydopamine-based reactions in the context of engineering various tissue types, including bone, blood vessels, cartilage, nerves, and muscle, is also provided.

Preparation of calcium phosphate cement and polymethyl methacrylate for biological composite bone cements.

BACKGROUND: We studied the biological safety, biomechanics, and tissue compatibility of calcium phosphate cement and Polymethyl Methacrylate composite bone cement mixed in different ratios. MATERIAL/METHODS: CPC and PMMA were mixed in different ratios (3:1, 2:1, 1:1, 1:2, 1:5, 1:10, 1:15, and 1:20). PMMA solvent is a general solvent containing a dissolved preparation of the composite bone cement specific to a given specimen to determine biological safety, biomechanics, and tissue compatibility. RESULTS: The CPC/PMMA (33%) group, CPC/PMMA (50%) group, CPC/PMMA (67%) group, and CPC/PMMA (75%) group were more in line with the composite bone cement without cytotoxicity requirements. The compressive strength of the CPC/PMMA (67%) group and CPC/PMMA (75%) group was 20 Mpa-30 Mpa, while that of the CPC/PMMA (4.8%) group, CPC/PMMA (6.25%) group, CPC/PMMA (9.1%) group, CPC/PMMA (16.7%) group, CPC/PMMA (33%) group, and CPC/PMMA (50%) group was 40 Mpa-70 Mpa. Curing time was longer in the CPC group (more than 11 min) and shorter in the PMMA group (less than 2 min). The results of weight loss rate showed that there were no significant differences between the CPC/PMMA group (4.8%, 6.25%, 9.1%, 16.7%, 33%) and PMMA control group (p>0.05). With the decrease of CPC content, the rate of weight loss gradually decreased. CONCLUSIONS: The CPC/PMMA (50%) group, CPC/PMMA (67%) group, and CPC/PMMA (75%) group provide greater variability and selectivity for the composite bone cement in obtaining better application.

Color assimilation of resin composites with adjacent color according to the distance.

STATEMENT OF PROBLEM: Color of esthetic restorative materials shifts toward color of adjacent material. PURPOSE: The purposes were to determine the amount of distance-dependent color shift in resin composites toward the color of adjacent materials and to define a color shift parameter (CSP) that can quantify this phenomenon. METHODS: Three brands of resin composites, two shades for each, were investigated. Specimens of 2 (thickness) × 4 (width) × 16 (length) mm(3) were fixed in an adjustable XY stage in contact with black and white ceramic tiles at each end. Color was measured by a spectroradiometer at seven separated points in 2-mm intervals, in which P1 was 2 mm away from the black tile. Mean value of the color differences (ΔE*ab ) between P1 and each of the other measurement points (P2-P6) was defined as the CSP, in which higher CSP value indicated smaller color assimilation toward P1 color. RESULTS: The range of the CSP was 7.5-12.4, which was influenced by the brand and shade of resin composites (p < 0.05). CONCLUSIONS: The CSP defined in this study provided the amount of color shift of esthetic materials toward adjacent color, which indicated the color assimilation effect of these materials. CLINICAL SIGNIFICANCE: The CSP investigated in the present study might be used to compare the tendency of color assimilation of esthetic restorative materials, and proper CSP ranges for optimal color assimilation or color blocking should be further determined.

[Analysis of 2 patients with occupational hard mental lung disease].

OBJECTIVE: We sought to master the clinical characteristics and prognosis of hard mental lung disease, improving this disease's diagnosis and treatment quality. METHODS: We recruited two suspected patients with hard mental lung disease and collected their occupational history, examination results of occupational health, and past medical records. By virtue of laboratory tests, high Kv chest radiography, CT and HRCT of chest, fiberoptic bronchoscopy and ECG examination, diagnostic report was synthesized respectively by respiratory physicians and pathologist from three different agencies. Then the report was submitted to diagnosis organizations of occupational disease, and diagnostic conclusion of occupational disease was drawn after discussion by at least three diagnosticians of occupational disease. RESULTS: We found that both of the two suspected patients were exposed to dusts of hard metal, and length of exposure service ranged from 8 to 9 years. Clinical manifestations were dominated by dry cough, wheezing after activities, and pathological manifestation was characteristic giant cell interstitial pneumonia. The prognosis and outcome of the disease were different. CONCLUSION: According to exact occupational exposure history, clinical manifestations, combined with the results of high Kv chest radiography, CT of chest and pathological manifestation, it can be diagnosed with hard mental lung disease.

Testing non-inferiority of a new treatment in three-arm clinical trials with binary endpoints.

BACKGROUND: A two-arm non-inferiority trial without a placebo is usually adopted to demonstrate that an experimental treatment is not worse than a reference treatment by a small pre-specified non-inferiority margin due to ethical concerns. Selection of the non-inferiority margin and establishment of assay sensitivity are two major issues in the design, analysis and interpretation for two-arm non-inferiority trials. Alternatively, a three-arm non-inferiority clinical trial including a placebo is usually conducted to assess the assay sensitivity and internal validity of a trial. Recently, some large-sample approaches have been developed to assess the non-inferiority of a new treatment based on the three-arm trial design. However, these methods behave badly with small sample sizes in the three arms. This manuscript aims to develop some reliable small-sample methods to test three-arm non-inferiority. METHODS: Saddlepoint approximation, exact and approximate unconditional, and bootstrap-resampling methods are developed to calculate p-values of the Wald-type, score and likelihood ratio tests. Simulation studies are conducted to evaluate their performance in terms of type I error rate and power. RESULTS: Our empirical results show that the saddlepoint approximation method generally behaves better than the asymptotic method based on the Wald-type test statistic. For small sample sizes, approximate unconditional and bootstrap-resampling methods based on the score test statistic perform better in the sense that their corresponding type I error rates are generally closer to the prespecified nominal level than those of other test procedures. CONCLUSIONS: Both approximate unconditional and bootstrap-resampling test procedures based on the score test statistic are generally recommended for three-arm non-inferiority trials with binary outcomes.

Are platelet concentrates an ideal biomaterial for arthroscopic rotator cuff repair? A meta-analysis of randomized controlled trials.

PURPOSE: The present study aims to conduct a meta-analysis of Level I evidence studies to investigate the efficacy of concomitant platelet concentrate (PC) used in arthroscopic rotator cuff repair. METHODS: We systematically searched electronic databases to identify randomized controlled trials (RCTs) evaluating the role of PC augmentation in arthroscopic rotator cuff repairs for patients with full-thickness tears. The search strategy followed the requirements in the Cochrane Library Handbook. The primary outcome was retearing of the rotator cuff. Functional outcomes were analyzed in terms of Constant score, specific Constant pain score, University of California, Los Angeles (UCLA) shoulder score, Simple Shoulder Test (SST) score, and American Shoulder and Elbow Surgeons (ASES) score. RESULTS: Seven studies with a total of 417 patients available at the latest follow-up reporting data about retears were analyzed in this meta-analysis. However, 4 studies with Constant scores (n = 237), 3 studies with UCLA scores (n = 168), 2 studies with Constant pain scores (n = 164), 2 studies with ASES scores (n = 101), and 2 studies with SST scores (n = 121) were analyzed. The retear rates and functional scores showed that there was no significant efficacy of PC application in arthroscopic rotator cuff repairs. CONCLUSIONS: This meta-analysis of high-level evidence suggests that PCs have no benefit regarding retear rate and overall clinical outcomes for the arthroscopic repair of full-thickness rotator cuff tears. LEVEL OF EVIDENCE: Level II, meta-analysis of randomized controlled trials.

Self-assembled lignin-based flame retardant hybrids carrying Cu2+ for poly(lactic acid) composites with improved fire safety and mechanical properties.

To enhance the flame retardancy and mechanical performance of PLA, a polyelectrolyte complex predicated on lignin was obtained by electrostatic mutual adsorption of ammonium polyphosphate (APP), polyethyleneimine (PEI), and copper ions as raw materials. The FT-IR spectra and EDX analysis confirmed the successful synthesis of a lignin-based flame retardant hybrid (APL-Cu2+) containing copper, phosphorus, and nitrogen elements. The combustion test results showed that the peak heat release rate and total heat release of the PLA composite containing 12 wt% APL-Cu2+ were decreased by 15.1 % and 18.2 %, respectively, as compared to those of pure PLA. The char residue morphology observation revealed that the addition of APL-Cu2+ could promote the formation of a highly dense and stable graphitized char layer, while TG-MS detected the emission of refractory gases such as ammonia gas, carbon dioxide, and water during combustion. The strong hydrogen bonding between APL-Cu2+ and the PLA matrix kept the composite maintaining good strength and toughness. The tensile strength and impact strength of PLA/6APL-Cu2+ increased by 4.73 % and 65.71 %, respectively, due to its high crystallinity and good interfacial compatibility. This work provides a feasible method to develop biobased flame retardant hybrids for PLA composites with better fire safety and improved mechanical properties.

Construction of sustainable and highly efficient fire-protective nanocoatings based on polydopamine and phosphorylated cellulose for flexible polyurethane foam.

Layer-by-layer (LBL) self-assembly is an effective strategy for constructing fire-resistant coatings on flexible polyurethane foam (FPUF), while the efficiency of fire-resistant coatings remains limited. Therefore, this study proposes an in situ flame retardancy modification combined with LBL self-assembly technology to enhance the efficiency of flame retardant coatings for FPUF. Initially, polydopamine (PDA) and polyethyleneimine (PEI) were employed to modify the FPUF skeleton, thereby augmenting the adhesion on the surface of the skeleton network. Then, the self-assembly of MXene and phosphorylated cellulose nanofibers (PCNFs) via the LBL technique on the foam skeleton network formed a novel, sustainable, and efficient flame retardant system. The final fire-protective coatings comprising PDA/PEI and MXenes/PCNF effectively prevented the collapse of the foam structure and suppressed the melt dripping of the FPUF during combustion. The peak heat release rate, the peak CO production rate and peak CO2 production rate were reduced by 68.6 %, 61.1 %, and 68.4 % only by applying a 10-bilayer coating. In addition, the smoke release rate and total smoke production were reduced by 83.3 % and 57.7 %, respectively. This work offers a surface modification approach for constructing highly efficient flame retardant coatings for flammable polymeric materials.

Remodeling Microenvironment for Implant-Associated Osteomyelitis by Dual Metal Peroxide.

Implant-associated osteomyelitis (IAOM) is characterized by bone infection and destruction; current therapy of antibiotic treatment and surgical debridement often results in drug resistance and bone defect. It is challenging to develop an antibiotic-free bactericidal and osteogenic-enhanced strategy for IAOM. Herein, an IAOM-tailored antibacterial and osteoinductive composite of copper (Cu)-strontium (Sr) peroxide nanoparticles (CSp NPs), encapsulated in polyethylene glycol diacrylate (PEGDA) (CSp@PEGDA), is designed. The dual functional CSp NPs display hydrogen peroxide (H2O2) self-supplying and Fenton catalytic Cu2+ ions' release, generating plenty of hydroxyl radical (•OH) in a pH-responsive manner for bacterial killing, while the released Sr2+ promotes the in vitro osteogenicity regarding cell proliferation, alkaline phosphatase activity, extracellular matrix calcification, and osteo-associated genes expression. The integration of Cu2+ and Sr2+ in CSp NPs together with the coated PEGDA hydrogel ensures the stable and sustainable ion release during short- and long-term periods. Benefitted from the injectablity and photo-crosslink ability, CSp@PEGDA is able to thoroughly fill the infectious site and gelate in situ for bacterial elimination and bone regeneration, which is verified through in vivo evaluation using a clinical-simulating IAOM mouse model. These favorable abilities of CSp@PEGDA precisely meet the multiple therapeutic needs and pave a promising way for implant-associated osteomyelitis treatment.