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Osteoinductive supplements without side effects stand out from the growth factors and drugs widely used in bone tissue engineering. Lithium magnesium sodium silicate hydrate (laponite) nanoflake is a promising bioactive component for bone regeneration, attributed to its inherent biosafety and effective osteoinductivity. Up to now, the in vivo osteogenic potential and mechanisms of laponite-encapsulated fibrous membranes remain largely unexplored. This study presents a unique method for homogeneously integrating high concentrations of laponite RDS into a polycaprolactone (PCL) matrix by dispersing laponite RDS sol into the polymer solution. Subsequently, a core-shell fibrous membrane (10RP-PG), embedding laponite-loaded PCL in its core, was crafted using coaxial electrospinning. The PCL core's slow degradation and the shell's gradient degradation enabled the sustained release of bioactive ions (Si and Mg) from laponite. In vivo studies on a critical-sized calvarial bone defect model demonstrated that the 10RP-PG membrane markedly enhanced bone formation and remodeling by accelerating the process of endochondral ossification. Further transcriptome analysis suggested that osteogenesis in the 10RP-PG membrane is driven by Mg and Si from endocytosed laponite, activating pathways related to ossification and endochondral ossification, including Hippo, Wnt and Notch. The fabricated nanocomposite fibrous membranes hold great promise in the fields of critical-sized bone defect repair.
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Polymer-based scaffolds with different degradability have been investigated to screen the matrix whose degradation rate is more closely matched with the bone regeneration rate. However, these comparisons are inclined to be compromised by the animal individual differences. In this study, we constructed an integrated scaffold model comprising four parts with different degradability and bioactivity to achieve an in situ comparison of bone regeneration ability of different scaffolds. Slow-degradable polycaprolactone (PCL), fast-degradable poly (lactic-co-glycolic acid) (PLGA), and silica-coated PCL and PLGA scaffolds were assembled into a round sheet to form a hydroxyapatite (HA)-free integrated scaffold. HA-doped PCL, PLGA, and silica-coated PCL and PLGA scaffolds were assembled to create an HA-incorporated integrated scaffold. The in vivo experimental results demonstrated that the local acid microenvironment caused by the rapid degradation of PLGA interfered with the osteogenic process promoted by PCL-based scaffolds in defect areas implanted with HA-free integrated scaffolds. Since the incorporation of HA alleviated the acidic microenvironment to some extent, each scaffold in HA-incorporated scaffolds exhibited its expected bone regeneration capacity. Consequently, it is feasible to construct an integrated structure for comparing the osteogenic effects of various scaffolds in situ, when there is no mutual interference between the materials. The strategy presented in this study inspired the structure design of biomaterials to enable in situ comparison of bone regeneration capacity of scaffolds.
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Durapatita , Osteogênese , Poliésteres , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Alicerces Teciduais , Alicerces Teciduais/química , Osteogênese/efeitos dos fármacos , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Poliésteres/química , Durapatita/química , Regeneração Óssea/efeitos dos fármacos , Polímeros/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ácido Poliglicólico/química , Engenharia Tecidual/métodos , Ácido Láctico/químicaRESUMO
Due to the decomposition temperature of Polyamide 66 (PA66) in the environment is close to its thermoforming temperature, it is difficult to construct porous scaffolds of PA66/nanohydroxyapatite (PA66/HAp) by fused deposition modeling (FDM) three-dimensional (3D) printing. In this study, we demonstrated for the first time a method for 3D printing PA66/HAp composites at room temperature, prepared PA66/HAp printing ink using a mixed solvent of formic acid/dichloromethane (FA/DCM), and constructed a series of composite scaffolds with varying HAp content. This printing system can print composite materials with a high HAp content of 60 wt %, which is close to the mineral content in natural bone. The physicochemical evaluation presented that the hydroxyapatite was uniformly distributed within the PA66 matrix, and the PA66/HAp composite scaffold with 30 wt % HAp content exhibited optimal mechanical properties and printability. The results of in vitro cell culture experiments indicated that the incorporation of HAp into the PA66 matrix significantly improved the cell adhesion, proliferation, and osteogenic differentiation of bone marrow stromal cells (BMSCs) cultured on the scaffold. In vivo animal experiments suggested that the PA66/HAp composite material with 30 wt % HAp content had the best structural maintenance and osteogenic performance. The three-dimensional PA66/HAp composite scaffold prepared by low temperature printing in the current study holds great potential for the repair of large-area bone defects.
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Durapatita , Células-Tronco Mesenquimais , Nylons , Impressão Tridimensional , Alicerces Teciduais , Durapatita/química , Alicerces Teciduais/química , Nylons/química , Animais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Engenharia Tecidual/métodos , Proliferação de Células/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Temperatura , Adesão CelularRESUMO
Diabetic chronic wounds pose significant clinical challenges due to their characteristic features of impaired extracellular matrix (ECM) function, diminished angiogenesis, chronic inflammation, and increased susceptibility to infection. To tackle these challenges and provide a comprehensive therapeutic approach for diabetic wounds, the first coaxial electrospun nanocomposite membrane is developed that incorporates multifunctional copper peroxide nanoparticles (n-CuO2 ). The membrane's nanofiber possesses a unique "core/sheath" structure consisting of n-CuO2 +PVP (Polyvinylpyrrolidone)/PCL (Polycaprolactone) composite sheath and a PCL core. When exposed to the wound's moist environment, PVP within the sheath gradually disintegrates, releasing the embedded n-CuO2 . Under a weakly acidic microenvironment (typically diabetic and infected wounds), n-CuO2 decomposes to release H2 O2 and Cu2+ ions and subsequently produce ·OH through chemodynamic reactions. This enables the anti-bacterial activity mediated by reactive oxygen species (ROS), suppressing the inflammation while enhancing angiogenesis. At the same time, the dissolution of PVP unveils unique nano-grooved surface patterns on the nanofibers, providing desirable cell-guiding function required for accelerated skin regeneration. Through meticulous material selection and design, this study pioneers the development of functional nanocomposites for multi-modal wound therapy, which holds great promise in guiding the path to healing for diabetic wounds.
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Diabetes Mellitus , Nanocompostos , Nanofibras , Humanos , Cicatrização , Pele/lesões , Nanocompostos/química , Nanofibras/química , InflamaçãoRESUMO
Both of the two citrus diseases, Alternaria brown spot (ABS) and Anthracnose, caused by Alternaria and Colletotrichum spp., respectively, can produce leaf lesions which are hard to differentiate. These two diseases have been confused as causal agents of brown spot for over a decade in China. In this study, citrus leaves with or without brown spot were collected from Zhaoqing, Guangdong and Wanzhou, Chongqing, and were further used for the taxonomic and functional comparisons between the co-occurring Alternaria and Colletotrichum species. In the amplicon sequencing, the average relative abundance and the composition of Alternaria, but not Colletotrichum, increased (from 0.1 to 9.9, p = 0.059; and to 0.7, p < 0.05) and significantly altered (p < 0.01) with the brown spot in Zhaoqing and Wanzhou, respectively. Two representative isolates Alternaria sp. F12A and Colletotrichum sp. F12C, from the same brown spot, were proved with different virulence and host response activation to citrus leaves. F12A caused typical symptoms of brown spot with the average spot length expanded to 5 and 6.1 cm, and also altered the citrus global gene expression 48 and 72 h after inoculation. In addition, F12A enriched the expression of genes that were most frequently involved in plant defense. In comparison, F12C caused leaf spot limited to the wounded site, and its milder activation of host response recovered 72 h after inoculation. Our study indicates that the incidence of brown spot in China is caused by Alternaria species, and the ABS should be a fungal disease of major concern on citrus.
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Bromine is an important resource that is widely used in medical, automotive, and electronic industries. Waste electronic products containing brominated flame retardants can cause serious secondary pollution, which is why catalytic cracking, adsorption, fixation, separation, and purification have gained significant attention. However, the bromine resources have not been effectively reutilized. The application of advanced pyrolysis technology could help solve this problem via converting bromine pollution into bromine resources. Coupled debromination and bromide reutilization during pyrolysis is an important field of research in the future. This prospective paper presents new insights in terms of the reorganization of different elements and adjustment of bromine phase transition. Furthermore, we proposed some research directions for efficient and environmentally friendly debromination and reutilization of bromine: 1) precise synergistic pyrolysis should be further explored for efficient debromination, such as using persistent free radicals in biomass, polymer hydrogen supply, and metal catalysis, 2) rematching of Br elements and nonmetal elements (C/H/O) will be a promising direction for synthesizing functionalized adsorption materials, 3) oriented control of the bromide migration path should be further studied to obtain different forms of bromine resources, and 4) advanced pyrolysis equipment should be well developed.
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Resíduo Eletrônico , Retardadores de Chama , Bromo , Brometos , Pirólise , Estudos Prospectivos , Resíduo Eletrônico/análiseRESUMO
Irisin is a hormone-like molecule mainly released by skeletal muscles in response to exercise, which is proposed to induce the 'browning' of white adipose tissue. Since its identification, irisin was reported to be closely associated with many metabolic diseases, including type 2 diabetes mellitus (T2DM), obesity, cardiovascular disease (CVD), and metabolic bone diseases. In recent years, irisin has attracted increasing research interest, and numerous studies have been published in this field. Thus, it is essential to identify the current research status of irisin and measure research hotspots and possible future trends. In this study, by utilizing two visualization software named CiteSpace and VOSviewer, we analyzed 1510 Web of Science publications on irisin published from 2012 to 2021. Our results show that the number of irisin-related articles published annually has increased significantly. China participates in the most studies, followed by the United States and Turkey. Firat University, Harvard University, and Shandong University are three major institutions with larger numbers of publications. The analysis of keywords co-occurrence indicates that insulin resistance, inflammation, and circulating irisin levels in serum are the research hotspots. Apoptosis, BDNF, and osteoporosis will likely become the focus of future research related to irisin. Overall, this study may provide helpful insights for researchers to understand the current research situation and identify the potential frontiers of irisin.
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Diabetes Mellitus Tipo 2 , Resistência à Insulina , Bibliometria , Fibronectinas , Humanos , Publicações , Estados UnidosRESUMO
A talent identification index system for male and female cross-country skiers in four age groups (11-12 years old, 13-14 years old, 15-16 years old, and 17-18 years old) was established. The system comprises five body shape indexes ( i =5): Leg-to-Body Ratio (LBR), body fat percentage, maturity status, spreaded brachia index, and upper extremity length. The physiological function indexes ( i =2) are VO2max and haemoglobin mass (Hb). The psychological indexes ( i =5) cover reaction time, perception speed, a quality-of-will scale, an attention test, and operational thinking. The physical fitness indexes ( i =11) comprise upper limb explosiveness, vertical jump, 3000-metre run, orthostatic forward flexion, closed-eyes single-leg stand, standing long jump, 20-metre sprint, pull-ups (males), flexed arm hang (females), hexagon jump, and a Functional Movement Screen (FMS) test. The athletic performance indexes ( i =3) comprise on-snow time trials for 1.2 km, 5 km, and 10 km. The talent identification evaluation model was created using automated evaluation software. The talent identification index system and evaluation standard table for cross-country skiers passed the P60 shortlist and P90 elite boundaries established using the percentile method. Thus, the results of this test profile verify that the evaluative model is objectively effective.
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Aptidão , Esqui/fisiologia , Esqui/psicologia , Adiposidade/fisiologia , Adolescente , Desempenho Atlético/fisiologia , Atenção/fisiologia , Estatura/fisiologia , Criança , China , Análise de Dados , Técnica Delphi , Estudos de Avaliação como Assunto , Teste de Esforço/métodos , Feminino , Hemoglobina A/análise , Humanos , Masculino , Modelos Teóricos , Percepção de Movimento/fisiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Desempenho Físico Funcional , Equilíbrio Postural/fisiologia , Tempo de Reação , Corrida/fisiologia , Fatores Sexuais , Somatotipos/fisiologia , Pensamento , Fatores de Tempo , Extremidade Superior/anatomia & histologia , Volição/fisiologiaRESUMO
OBJECTIVE: To understand the antimicrobial resistance, virulence factors, and molecular characterization of MRSA isolates cultured from ready-to-eat(RTE) foods from several provinces in China. METHODS: Totally, 397 S. aureus isolates were collected from RTE foods from several provinces in China, in 2017. The mecA gene was amplified to detect the MRSA strains among all 397 isolates by a polymerase chain reaction(PCR) method. Furthermore, the antimicrobial susceptibility and virulence factors of the MRSA isolates were detected by broth microdilution method and PCR, respectively, while the molecular characterization of all MRSA isolates were analyzed by pulsed-field gel electrophoresis(PFGE). RESULTS: In total, 32 MRSA isolates were identified from 397 isolates. All 32 MRSA isolates were resistant to penicillin, oxacillin and cefoxitin. Meanwhile, 78. 1%, 65. 6%, 53. 1, 28. 1% and 12. 5% of the 32 MRSA isolates showed resistant to erythromycin, clindamycin, tetracycline, chloramphenicol, and ciprofloxacin, respectively. Resistance rates to gentamicin and trimethoprim-sulfamethoxazole of all MRSA isolates were less than 10%. Eleven drug resistant spectrums were identified and 29 out of 32 MRSA isolates were identified as multi-drug resistant(MDR) isolates and two isolates were found to resistant to 9 antimicrobial agents tested in this study. Of all, 27 MRSA isolates were detected to harboring 13 virulence genes with sel-q(56. 3%), sel-k(43. 8%), seb(28. 1%) and sec(18. 8%) genes being the top four frequently detected. Besides, the result also showed that two or more virulence genes could be detected in one MRSA isolate. Finally, all 32 MRSA were identified to have 26 PFGE patterns and no dominant PFGE patterns were found in this study. CONCLUSION: An overall high level antimicrobial resistance was found among RTE associated MRSA in China in 2017, so was the MDR condition. Virulence genes could be frequently detected in RTE associated MRSA isolates. The PFGE patterns of RTE associated MRSA showed wide distribution characteristics.
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Farmacorresistência Bacteriana Múltipla , Contaminação de Alimentos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Fatores de Virulência/genética , Antibacterianos/farmacologia , China , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Testes de Sensibilidade MicrobianaRESUMO
An environmentally friendly technology of cryogenic grinding for recovering cathode materials from spent lithium-ion batteries was has been investigated in this paper. Differential Scanning Calorimeter was used to test the glass transition temperature of the organic binder. Advanced analysis techniques, a microcomputer-controlled electronic universal material-testing machine, a low-temperature impact testing machine, scanning electron microscopy and high-resolution 3 Dimension-X-ray microscopy, were utilized to analyze the effect of low temperature on the mechanical properties and morphology of cathode. Results show that the yield strength, tensile strength and impact strength of the current collector is significantly increased at low temperature, that the glass transition temperature of the organic binder is approximately 235â¯K. Low temperature enhances the strength of the current collector and causes the organic binder to fail. Therefore, cryogenic grinding could realize the selective grinding of the cathode and significantly improve the peel-off of the electrode materials. The peel-off efficiency of cathode materials was improved from 25.03% to 87.29% at the optimum conditions of low temperature pretreatment for 5â¯min and cryogenic grinding for 30â¯s. The experiments demonstrate that the cryogenic grinding can obviously facilitate the efficient recovery of cathode materials, revealing a great application prospective for the recycling of spent lithium-ion batteries.
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Fontes de Energia Elétrica , Lítio , Eletrodos , Estudos Prospectivos , ReciclagemRESUMO
Recycling of valuable metals from spent lithium ion batteries (LIBs) is of great significance considering the conservation of metal resources and the alleviation of potential hazardous effects on environment. Thus, the present work focuses on enhancing the efficiency of leaching process for the recovery of cobalt and lithium from the cathode active materials of spent LIBs. In this study, benzenesulfonic acid (C6H5SO3H) with a reducing agent hydrogen peroxide (H2O2) was innovatively used as leaching reagents, and the operating variables were optimized to obtain higher leaching efficiencies. Results show the optimized leaching recovery of 99.58% Li and 96.53% Co was obtained under the conditions of 0.75â¯M benzenesulfonic acid, 3â¯vol% H2O2, a solid to liquid (S/L) ratio of 15â¯g/L, 500â¯rpm stirring speed, and 80â¯min leaching time at 90⯰C. Moreover, a new kinetic model was introduced to describe the leaching kinetics of LiCoO2 from the cathode material. The apparent activation energies Ea for leaching of lithium and cobalt are 41.06 and 35.21â¯kJ/mol, respectively, indicating that the surface chemical reaction is the rate-controlling step during this leaching process. Further, the proposed recovery mechanism for spent cathode material was raised by analyzing the experimental results and characterizing the morphological and chemical state (i.e. SEM-EDS, XPS and XRD) of raw material and leaching residues. In comparison with the previous leaching process, this research was found to be efficient, low energy consumption, and environmental friendly.
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Cobalto , Lítio , Benzenossulfonatos , Fontes de Energia Elétrica , Peróxido de Hidrogênio , ReciclagemRESUMO
In complex discrete manufacturing environment, there used to be a poor network and an isolated information island in production line, which led to slow information feedback and low utilization ratio, hindering the construction of enterprise intelligence. To solve these problems, uncertain factors in the production process and demands of sensor network were analyzed; hierarchical topology design method and the deployment strategy of the complexity industrial internet of things were proposed; and a big data analysis model and a system security protection system based on the network were established. The weight of each evaluation index was calculated using analytic hierarchy process, which established the intelligentized evaluation system and model. An actual production scene was also selected to validate the feasibility of the method. A diesel engine production workshop and the enterprise MES were used as an example to establish a network topology. The intelligence level based on both subjective and objective factors were evaluated and analyzed considering both quantitative and qualitative aspects. Analysis results show that the network topology design method and the intelligentize evaluation system were feasible, could improve the intelligence level effectively, and the network framework was expansible.
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Extended-spectrum ß-lactamases (ESBLs)-producing Salmonella is a tremendous hazard to food safety and public health. The objective of this study was to determine the prevalence of 30 virulence genes (avrA, sipA, sseC, marT, rhuM, siiE, pipA, pipD, envR, gogB, gtgA, sodC1, sseI, irsA, sopE2, spvC, rck, spvR, fhuA, msgA, pagK, srfj, stkc, fimA, lpfD, pefA, stcC, steB, stjB, and tcfA) in 156 ESBLs-producing Salmonella isolates that belonged to 21 serotypes. These isolates were recovered from retail raw chicken samples collected from 5 provinces and 2 national cities in China between 2007 and 2012. The results indicated that 154 (98.7%) ESBLs-producing Salmonella isolates carried at least 1 virulence gene, 138 (88.5%) simultaneously carried at least 5 virulence genes, 107 (68.6%) carried 10 or more, and 20 (12.8%) carried 15 or more virulence genes. The most frequently detected virulence genes were marT (n = 127, 81.4%), siiE (n = 126, 80.8%), msgA (n = 121, 77.6%), and sipA (n = 121, 77.6%). Significant difference was identified between detection percentages of virulence genes of rhuM, pipD, envR, sopE2, pagK, lpfD, steB, and stjB in S. Indiana, S. Thompson, S. Enteritidis, S. Typhimurium, S. Shubra, S. Edinburg, and S. Agona isolates. Distribution of virulence genes were significantly influenced by sampling districts (P < 0.01), especially for sodC1 and pipD, and then were msgA and sopE2. The heatmap showed the frequencies of virulence genes in ESBLs-producing isolates from retail chickens in southern, central, and northern regions of China were completely different from each other. Based on our findings, ESBLs-producing Salmonella of retail chicken origin were common carriers of multiple virulence genes and were regionally distributed.
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Galinhas/microbiologia , Genes Bacterianos , Aves Domésticas/microbiologia , Salmonella/genética , beta-Lactamases/genética , Animais , China , Contaminação de Alimentos , Microbiologia de Alimentos , Salmonella/enzimologia , Fatores de Virulência/genéticaRESUMO
An oscillatory emulsification system for the production of oil in water emulsions using a commercially available low-cost woven metal microscreen (WMMS) is investigated. The system allows for independent control of both the oscillation frequencies and amplitudes such that it provides two degrees of freedom for controlling the emulsion properties. The investigations included the production of both surfactant and particle-stabilized emulsions. The average droplet size was found to decrease when both the oscillation frequency and amplitude was increased. For surfactant-stabilized emulsions, using bi-surfactants in both the continuous and dispersed phases resulted in a smaller droplet size due to lower interfacial tension. For particle-stabilized emulsions, both the hydrodynamics of the system and the hydrophobic and hydrophilic nature of the stabilizing particles influenced the interfacial properties at the oil-water interface, which in turn affected the final droplet size and distribution with potential droplet breakage. In absence of the latter, a simple torque balance model can be used to reasonably predict the average emulsion droplet size.