RESUMO
OBJECTIVES: To evaluate the accuracy of implant placement using a dynamic navigation system in fully edentulous jaws and to analyze the influence of implant distribution on implant position accuracy. MATERIALS AND METHODS: Edentulous patients who received implant placement using a dynamic navigation system were included. Four to six mini screws were placed in the edentulous jaw under local anesthesia as fiducial markers. Then patients received CBCT scans. Virtual implant positions were designed in the planning software based on CBCT data. Under local anesthesia, implants were inserted under the guidance of the dynamic navigation system. CBCTs were taken following implant placement. The deviation between the actual and planned implant positions was measured by comparing the pre- and postsurgery CBCT. RESULTS: A total of 13 edentulous patients with 13 edentulous maxillae and 7 edentulous mandibles were included, and 108 implants were placed. The average linear deviations at the implant entry point and apex were 1.08 ± 0.52 mm and 1.15 ± 0.60 mm, respectively. The average angular deviation was 2.85 ± 1.20°. No significant difference was detected in linear and angular deviations between the maxillary and mandibular implants, neither between the anterior and posterior implants. CONCLUSIONS: The dynamic navigation system provides high accuracy for implant placement in fully edentulous jaws, while the distribution of the implants showed little impact on implant position accuracy.
Assuntos
Implantes Dentários , Arcada Edêntula , Boca Edêntula , Cirurgia Assistida por Computador , Humanos , Implantação Dentária Endóssea , Estudos Retrospectivos , Tomografia Computadorizada de Feixe Cônico , Arcada Edêntula/diagnóstico por imagem , Arcada Edêntula/cirurgia , Boca Edêntula/diagnóstico por imagem , Boca Edêntula/cirurgia , Computadores , Desenho Assistido por Computador , Imageamento TridimensionalRESUMO
Orthodontic treatment in adults is often related to longer treatment time as well as higher periodontal risks compared to adolescents. The aim of this review is to explore the influence of age-related chages on orthodontic tooth movement (OTM) from macro and micro perspectives. Adults tend to show slower tooth movement speed compared to adolescence, especially during the early phase. Under orthodontic forces, the biological responses of the periodontal ligament (PDL) and alveolar bone is different between adult and adolescents. The adult PDL shows extended disorganization time, increased cell senescence, less cell signaling and a more inflammatory microenvironment than the adolescent PDL. In addition, the blood vessel surface area is reduced during the late movement phase, and fiber elasticity decreases. At the same time, adult alveolar bone shows a higher density, as well as a reduced osteoblast and osteoclast activation, under orthodontic forces. The local cytokine expression also differs between adults and adolescents. Side-effects, such as excessive root resorption, greater orthodontic pain, and reduced pulpal blood flow, also occur more frequently in adults than in adolescents.
RESUMO
The comprehensive investigation of protein phosphorylation and glycosylation aids in the discovery of novel biomarkers as well as the understanding of the pathophysiology of illness. In this work, a nitrogen/titanium-rich porous organic polymer was developed by copolymerizing carbohydrazide (CH) and 2,3-dihydroxyterephthalaldehyde (2,3-Dha) and modifying with Ti4+ (CH-Dha-Ti4+). The adequate nitrogen contributes to the enrichment of glycopeptides via HILIC, while titanium benefits from capturing phosphopeptides through IMAC. The proposed method exhibits excellent selectivity (1 : 1000, both for glycopeptides and phosphopeptides), LOD (for glycopeptides: 0.05 fmol µL-1, for phosphopeptides: 0.2 fmol), loading capacity (for glycopeptides: 100 mg g-1, for phosphopeptides: 125 mg g-1) and size-exclusion effect (1 : 10 000, both for glycopeptides and phosphopeptides). Furthermore, CH-Dha-Ti4+ was applied to capture glycopeptides and phosphopeptides from human serum; 205 glycopeptides and 45 phosphopeptides were detected in the serum of normal controls; and 294 glycopeptides and 63 phosphopeptides were found in the serum of uremia patients after being analyzed by nano LC-MS/MS. The discovered glycopeptides and phosphopeptides were involved in several molecular biological processes and activities, according to a gene ontology study.
Assuntos
Fosfopeptídeos , Polímeros , Humanos , Fosfopeptídeos/química , Fosfopeptídeos/metabolismo , Titânio/química , Glicopeptídeos/química , Porosidade , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Orthodontic tooth movement (OTM) is a dynamic equilibrium of bone remodeling, involving the osteogenesis of new bone and the osteoclastogenesis of old bone, which is mediated by mechanical force. Periodontal ligament stem cells (PDLCSs) in the periodontal ligament (PDL) space can transmit mechanical signals and regulate osteoclastogenesis during OTM. KAT6A is a histone acetyltransferase that plays a part in the differentiation of stem cells. However, whether KAT6A is involved in the regulation of osteoclastogenesis by PDLSCs remains unclear. RESULTS: In this study, we used the force-induced OTM model and observed that KAT6A was increased on the compression side of PDL during OTM, and also increased in PDLSCs under compression force in vitro. Repression of KAT6A by WM1119, a KAT6A inhibitor, markedly decreased the distance of OTM. Knockdown of KAT6A in PDLSCs decreased the RANKL/OPG ratio and osteoclastogenesis of THP-1. Mechanistically, KAT6A promoted osteoclastogenesis by binding and acetylating YAP, simultaneously regulating the YAP/TEAD axis and increasing the RANKL/OPG ratio in PDLSCs. TED-347, a YAP-TEAD4 interaction inhibitor, partly attenuated the elevation of the RANKL/OPG ratio induced by mechanical force. CONCLUSION: Our study showed that the PDLSCs modulated osteoclastogenesis and increased the RANKL/OPG ratio under mechanical force through the KAT6A/YAP/TEAD4 pathway. KAT6A might be a novel target to accelerate OTM.
Assuntos
Histona Acetiltransferases , Osteogênese , Osteoprotegerina , Ligamento Periodontal , Ligante RANK , Técnicas de Movimentação Dentária , Fatores de Transcrição , Animais , Humanos , Proteínas de Ligação a DNA/metabolismo , Histona Acetiltransferases/metabolismo , Osteoclastos/metabolismo , Osteogênese/fisiologia , Osteoprotegerina/metabolismo , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Ligante RANK/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco , Técnicas de Movimentação Dentária/métodos , Fatores de Transcrição/metabolismoRESUMO
The structure and surface physicochemical properties of anode play a crucial role in microbial fuel cells (MFCs). To enhance the enrichment of exoelectrogen and facilitate extracellular electron transfer (EET), a three-dimensional macroporous graphene aerogel with polydopamine coating was successfully introduced to modify carbon brush (PGA/CB). The three-dimensional graphene aerogel (GA) with micrometer pores improved the space utilization efficiency of microorganisms. Polydopamine (PDA) coating enhanced the physicochemical properties of the electrode surface by introducing abundant functional groups and nitrogen-containing active sites. MFCs equipped with PGA/CB anodes (PGA/CB-MFCs) demonstrated superior power generation compared to GA/CB-MFCs and CB-MFCs (MFCs with GA/CB and CB anodes respectively), including a 23.0 % and 30.1 % reduction in start-up time, and an increase in maximum power density by 2.43 and 1.24 times respectively. The higher bioelectrochemical activity exhibited by the biofilm of PGA/CB anode and the promoted riboflavin secretion by PGA modification imply the enhanced EET efficiency. 16S rRNA high-throughput sequence analysis of the biofilms revealed successful enrichment of Geobacter on PGA/CB anodes. These findings not only validate the positive impact of the synergistic effects between GA and PDA in promoting EET and improving MFC performance but also provide valuable insights for electrode design in other bioelectrochemical systems.
Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Grafite , Indóis , Polímeros , Indóis/química , Indóis/metabolismo , Fontes de Energia Bioelétrica/microbiologia , Polímeros/química , Grafite/química , Transporte de Elétrons , Biofilmes , Géis/químicaRESUMO
Background/purpose: External root resorption is a main side effect of orthodontic treatment and is more likely to occur on the pression side than the tension side. To explore the potential protective mechanisms on the tension side, this study investigated the influence of mechanical tension on cementoblast mineralization and elucidated the role of autophagy in mediating this process. Materials and methods: Mechanical tension was applied to cementoblasts using iStrain. The expression of mineralization-related and autophagy-related markers was detected by qRT-PCR, Western blot analysis, and immunofluorescence staining. RNA sequencing identified key regulators. Immunohistochemical staining assessed related markers expression in in vivo experiments. Results: Applying tension to cementoblasts increased mineralization-related gene expression in a force-dependent and time-dependent manner. The immunohistochemical staining result of in vivo experiments supported these findings, demonstrating elevated expression of mineralization markers under tension. Mechanical tension also enhanced autophagic activity in cementoblasts, which was demonstrated by the results of qRT-PCR, Western blot analysis, immunofluorescence staining, and in vivo experiments. Suppression of autophagy with chloroquine attenuated the mineralization of cementoblasts induced by tension stimulus. RNA-seq identified Postn as a key regulator, and the knockdown of Postn impaired the mechanical tension-promoted mineralization of cementoblasts. Conclusion: This study proposed the tension-induced promotion in mineralization of cementoblasts and emphasized the mediating role of autophagy in this process. Postn, a mediator connecting autophagy and mineralization, was identified as a key regulator. These discoveries helped elucidate orthodontic-related microprocesses on tooth roots and offer potential targets for therapeutic interventions to prevent and restore external root resorption clinically.
RESUMO
The CO2 bioelectromethanosynthesis via two-chamber microbial electrolysis cell (MEC) holds tremendous potential to solve the energy crisis and mitigate the greenhouse gas emissions. However, the membrane fouling is still a big challenge for CO2 bioelectromethanosynthesis owing to the poor proton diffusion across membrane and high inter-resistance. In this study, a new MEC bioreactor with biogas recirculation unit was designed in the cathode chamber to enhance secondary-dissolution of CO2 while mitigating the contaminant adhesion on membrane surface. Biogas recirculation improved CO2 re-dissolution, reduced concentration polarization, and facilitated the proton transmembrane diffusion. This resulted in a remarkable increase in the cathodic methane production rate from 0.4 mL/L·d to 8.5 mL/L·d. A robust syntrophic relationship between anodic organic-degrading bacteria (Firmicutes 5.29%, Bacteroidetes 25.90%, and Proteobacteria 6.08%) and cathodic methane-producing archaea (Methanobacterium 65.58%) enabled simultaneous organic degradation, high CO2 bioelectromethanosynthesis, and renewable energy storage.
Assuntos
Biocombustíveis , Reatores Biológicos , Dióxido de Carbono , Metano , Dióxido de Carbono/análise , Eletrólise , Eletrodos , Fontes de Energia Bioelétrica , Methanobacterium/metabolismo , Membranas Artificiais , Proteobactérias/metabolismoRESUMO
Electrochemical anaerobic membrane bioreactor (EC-AnMBR) by integrating a composite anodic membrane (CAM), represents an effective method for promoting methanogenic performance and mitigating membrane fouling. However, the development and formation of electroactive biofilm on CAM, and the spatio-temporal distribution of key functional microorganisms, especially the degradation mechanism of organic pollutants in metabolic pathways were not well documented. In this work, two AnMBR systems (EC-AnMBR and traditional AnMBR) were constructed and operated to identify the role of CAM in metabolic pathway on biogas upgrading and mitigation of membrane fouling. The methane yield of EC-AnMBR at HRT of 20 days was 217.1 ± 25.6 mL-CH4/g COD, about 32.1â¯% higher compared to the traditional AnMBR. The 16S rRNA analysis revealed that the EC-AnMBR significantly promoted the growth of hydrolysis bacteria (Lactobacillus and SJA-15) and methanogenic archaea (Methanosaeta and Methanobacterium). Metagenomic analysis revealed that the EC-AnMBR promotes the upregulation of functional genes involved in carbohydrate metabolism (gap and kor) and methane metabolism (mtr, mcr, and hdr), improving the degradation of soluble microbial products (SMPs)/extracellular polymeric substances (EPS) on the CAM and enhancing the methanogens activity on the cathode. Moreover, CAM biofilm exhibits heterogeneity in the degradation of organic pollutants along its vertical depth. The bacteria with high hydrolyzing ability accumulated in the upper part, driving the feedstock degradation for higher starch, sucrose and galactose metabolism. A three-dimensional mesh-like cake structure with larger pores was formed as a biofilter in the middle and lower part of CAM, where the electroactive Geobacter sulfurreducens had high capabilities to directly store and transfer electrons for the degradation of organic pollutants. This outcome will further contribute to the comprehension of the metabolic mechanisms of CAM module on membrane fouling control and organic solid waste treatment and disposal.
Assuntos
Biocombustíveis , Reatores Biológicos , Membranas Artificiais , Reatores Biológicos/microbiologia , Anaerobiose , RNA Ribossômico 16S/genética , Metano/metabolismo , Biofilmes , Bactérias/metabolismo , Incrustação BiológicaRESUMO
The treatment of osteoporotic bone defect remains a big clinical challenge because osteoporosis (OP) is associated with oxidative stress and high levels of reactive oxygen species (ROS), a condition detrimental for bone formation. Anti-oxidative nanomaterials such as selenium nanoparticles (SeNPs) have positive effect on osteogenesis owing to their pleiotropic pharmacological activity which can exert anti-oxidative stress functions to prevent bone loss and facilitate bone regeneration in OP. In the current study a strategy of one-pot method by introducing Poly (lactic acid-carbonate) (PDT) and ß-Tricalcium Phosphate (ß-TCP) with SeNPs, is developed to prepare an injectable, anti-collapse, shape-adaptive and adhesive bone graft substitute material (PDT-TCP-SE). The PDT-TCP-SE bone graft substitute exhibits sufficient adhesion in biological microenvironments and osteoinductive activity, angiogenic effect and anti-inflammatory as well as anti-oxidative effect in vitro and in vivo. Moreover, the PDT-TCP-SE can protect BMSCs from erastin-induced ferroptosis through the Sirt1/Nrf2/GPX4 antioxidant pathway, which, in together, demonstrated the bone graft substitute material as an emerging biomaterial with potential clinical application for the future treatment of osteoporotic bone defect. STATEMENT OF SIGNIFICANCE: Injectable, anti-collapse, adhesive, plastic and bioactive bone graft substitute was successfully synthesized. Incorporation of SeNPs with PDT into ß-TCP regenerated new bone in-situ by moderating oxidative stress in osteoporotic bone defects area. The PDT-TCP-SE bone graft substitute reduced high ROS levels in osteoporotic bone defect microenvironment. The bone graft substitute could also moderate oxidative stress and inhibit ferroptosis via Sirt1/Nrf2/GPX4 pathway in vitro. Moreover, the PDT-TCP-SE bone graft substitute could alleviate the inflammatory environment and promote bone regeneration in osteoporotic bone defect in vivo. This biomaterial has the advantages of simple synthesis, biocompatibility, anti-collapse, injectable, and regulation of oxidative stress level, which has potential application value in bone tissue engineering.
Assuntos
Regeneração Óssea , Substitutos Ósseos , Fosfatos de Cálcio , Osteoporose , Estresse Oxidativo , Estresse Oxidativo/efeitos dos fármacos , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Osteoporose/patologia , Osteoporose/terapia , Osteoporose/tratamento farmacológico , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/química , Ratos Sprague-Dawley , Selênio/química , Selênio/farmacologia , Feminino , Osteogênese/efeitos dos fármacos , Poliésteres/química , Poliésteres/farmacologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos , InjeçõesRESUMO
The purpose of this study was to fabricate poly(epsilon-caprolactone) (PCL)/poly ethylene oxid (PEO)/chitosan (CS) ultrafine fiber in both aligned and random structures using electrospinning technique and their process parameters were optimized. The aligned and random PCL/PEO/chitosan ultrafine fibers were also used as scaffold for tissue engineering and their cell affinity was investigated. In the first part, we inspected the effect of environment conditions, solution properties, process parameters on PCL/PEO/chitosan ultrafine fiber. In the second part, the apparatus of electrospinning to manufacture highly aligned PCL/PEO/chitosan ultrafine fiber was developed. The effects of process parameters such as flow rate, design of collector and rotation speed of collecting drum on the morphology of ultrafine fiber were discussed. In addition, the cross link of PCL/PEO/chitosan ultrafine fiber by cross-linking agent was examined, too. The physical properties, chemical properties, and cell affinities of the aligned PCL/PEO/chitosan ultrafine fiber with or without cross link were measured. The chemical analysis and tensile strength of the ultrafine fiber were characterized using Fourier Transfer Infared Spectrophotometer and Universal Tensile Machine, respectively. The results show that the aligned PCL/PEO/chitosan ultrafine fibrous mat had the capacity to induce cellular alignment and enhance cellular elongation.
Assuntos
Quitosana/química , Células-Tronco Mesenquimais/citologia , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Animais , Células Cultivadas , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Células-Tronco Mesenquimais/fisiologia , Conformação Molecular , RatosRESUMO
Human papillomavirus infection can cause a variety of benign or malignant oral lesions, and the various genotypes can cause distinct types of lesions. To our best knowledge, there has been no report of 2 different human papillomavirus-related oral lesions in different oral sites in the same patient before. This paper reported a patient with 2 different oral lesions which were clinically and histologically in accord with focal epithelial hyperplasia and oral papilloma, respectively. Using DNA extracted from these 2 different lesions, tissue blocks were tested for presence of human papillomavirus followed by specific polymerase chain reaction testing for 6, 11, 13, 16, 18, and 32 subtypes in order to confirm the clinical diagnosis. Finally, human papillomavirus-32-positive focal epithelial hyperplasia accompanying human papillomavirus-16-positive oral papilloma-like lesions were detected in different sites of the oral mucosa. Nucleotide sequence sequencing further confirmed the results. So in our clinical work, if the simultaneous occurrences of different human papillomavirus associated lesions are suspected, the multiple biopsies from different lesions and detection of human papillomavirus genotype are needed to confirm the diagnosis.
Assuntos
Alphapapillomavirus/isolamento & purificação , Hiperplasia Epitelial Focal/virologia , Papillomavirus Humano 16/fisiologia , Neoplasias Bucais/virologia , Papiloma/virologia , Infecções por Papillomavirus/virologia , Alphapapillomavirus/classificação , Biópsia , Criança , Genótipo , Neoplasias Gengivais/virologia , Papillomavirus Humano 11/isolamento & purificação , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Papillomavirus Humano 6/isolamento & purificação , Humanos , Masculino , Reação em Cadeia da Polimerase , Neoplasias da Língua/virologiaRESUMO
Accounting for more than half of the total primary microplastic (MP) emissions, and one-sixth of the total marine MP pollution in China in 2015, tire wear particles (TWP) are inevitable to age and interact with co-existing species, thus pose a potential risk to the surroundings. The impacts of simulated ultraviolet radiation weathering and liquid-phase potassium persulfate oxidation of TWP on the surface physicochemical properties were comparatively explored. The characterization results demonstrated that the content of carbon black, particle size and specific surface area of the aged TWP all decreased, while the changes of the hydrophobicity and polarity were inconsistent. The interfacial interactions with tetracycline (TC) in aqueous were investigated, the well fitted pseudo-second-order kinetics, Dual-mode Langmuir and Scatchard isotherm models indicated the attachment of TC dominated by surface adsorption at lower concentration, and there's a positive synergistic effect among the main sorption domains. Moreover, the results of the influences of co-existing salts and natural organic matter revealed that the potential risks of TWP elevated by the adjacent media in natural compartment. This work provides new insights into the way that TWP interact with contaminants in the real environment.
Assuntos
Compostos Heterocíclicos , Poluentes Químicos da Água , Plásticos , Raios Ultravioleta , Tetraciclina , Antibacterianos , Microplásticos/química , Adsorção , Poluentes Químicos da Água/análiseRESUMO
Wound healing from bacterial infections is one of the major challenges in the biomedical field. The traditional single administration methods are usually accompanied with side effects or unsatisfactory efficacy. Herein, we design dynamically evolving antibacterial and repair-promoting nanocomposites (NCs) by in situ self-assembling of zeolitic imidazolate framework-8 (ZIF-8) on the surface of barium titanate (BTO), and further loading with a small amount of ciprofloxacin (CIP). The new strategy of combining pH-stimulated drug delivery and ultrasound-controlled sonodyamics has the potential to dynamically evolve in infected wound sites, offering a multifunctional therapy. In vitro study demonstrates that the enhancement generation of reactive oxygen species through the sonodynamic process due to the heterostructures and a small amount of CIP released in an acidic environment are synergistically antibacterial, and the inhibition rate was >99.9%. In addition, reduced sonodynamic effect and Zn2+ generated along with the gradual degradation of ZIF-8 simultanously promote cell migration and tissue regeneration. The in vivo study of full-thickness skin wounds in mouse models demonstrate a healing rate of 99.3% could be achieved under the treatment of BTO@ZIF-8/CIP NCs. This work provides a useful improvement in rational design of multi-stimulus-responsive nanomaterials for wound healing. STATEMENT OF SIGNIFICANCE: A novel piezoelectric nanocomposite was proposed to realize sonodynamic therapy and pH-stimulated drug releasing simultaneously in wound healing treatment. The dynamically evolving structure of the piezoelectric nanocomposite in acidic microenvironment has been theoretically and experimentally verified to contribute to a continuous variation of sonodymanic strength, which accompanied with the gradual releasing of drug and biocompatible Zn2+effectively balanced antibacterial and repair-promoting effects. Both of the in vitro and in vivo study demonstrated that the strategy could significantly accelerate wound healing, inspiring researchers to optimize the design of multi-stimulus-responsive nanomaterials for various applications in biomedical and biomaterial fields.
Assuntos
Antibacterianos , Nanocompostos , Camundongos , Animais , Antibacterianos/uso terapêutico , Cicatrização , Nanocompostos/uso terapêutico , Nanocompostos/química , Sistemas de Liberação de Medicamentos , Materiais Biocompatíveis/farmacologiaRESUMO
Due to the limited self-repairing capacity after peripheral nerve injuries (PNI), artificial nerve conduits are widely applied to facilitate neural regeneration. Exogenous electrical stimulation (ES) that is carried out by the conductive conduit regulates the biological behavior of Schwann cells (SCs). Meanwhile, a longitudinal surface structure counts to guide axonal growth to accelerate the end-to-end connection. Currently, there are no conduits equipped with both electrical conduction and axon-guiding surface structure. Herein, a biodegradable, conductive poly(l-lactide-co-caprolactone)/graphene (PLCL/GN) composite conduit is designed. The conduit with 20.96 ± 1.26 MPa tensile strength has a micropatterned surface of 20 µm groove fabricated by microimprint technology and self-assembled polydopamine (PDA). In vitro evaluation shows that the conduits with ES effectively stimulate the directional cell migration, adhesion, and elongation, and enhance neuronal expression of SCs. The rat sciatic nerve crush model demonstrates that the conductive micropatterned conduit with ES promotes the growth of myelin sheath, faster nerve regeneration, and 20-fold functional recovery in vivo. These discoveries prove that the PLCL(G)/PDA/GN composite conduit is a promising tool for PNI treatment by providing the functional integration of physical guidance, biomimetic biological regulation, and bioelectrical stimulation, which inspires a novel therapeutic approach for nerve regeneration in the future.
Assuntos
Traumatismos dos Nervos Periféricos , Polímeros , Ratos , Animais , Polímeros/química , Nervo Isquiático/lesões , Nervo Isquiático/fisiologia , Indóis/farmacologia , Regeneração Nervosa/fisiologiaRESUMO
The landfills store a lot of waste plastics, thus it has been confirmed a main source for the occurrence of plastics/microplastic. Although there are some reports that microplastics (MPs) can generate in leachate and refuse samples from the landfill, it exist many blanks for the evolution of physical and chemical characteristics of waste plastics and microplastics with different landfill age. To explore the process that large pieces of plastic are fractured into microplastics, the waste plastics with landfill age from 7 to 30 years are surveyed from a typical landfill in Shanghai. The results show that PE and PP are the most common types of landfilling plastics, and their chemical composition also have changed due to the creation of CO and -OH. Moreover, the crystallinity is affected by plastic type and landfill age. The crystallinity of PP increased from 24.9% to 56.8%, but for PE, the crystallinity decreased from 55.6% to 20.8%. The mechanical properties of waste plastics were reduced significantly, which may be caused by changes in carbon-chain molecules. Al, Ti, Co, and other metal elements were detected on the plastic surface. The hydrophobic behavior of waste plastic is constantly decreasing (102.2°-80.1°) under long-term landfilling. By investigating the changes in the physical and chemical characteristics of waste plastics with different landfill age can shed light upon the process of environmental weathering of waste plastics. This provide theoretical guidance for reducing the transport of microplastics to the environment.
Assuntos
Microplásticos , Poluentes Químicos da Água , China , Plásticos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análiseRESUMO
Increasing microplastics (MPs) pollution in estuaries profoundly impacts microbial ecosystems and biogeochemical processes. Nitrous oxide (N2O), a powerful greenhouse gas, is an important intermediate product of microbial nitrogen cycling. However, how MPs regulate N2O production and its pathways remain poorly understood. Here, impacts of traditional petroleum-based and emerging biodegradable MPs on microbial N2O production and its pathways were studied through dual-isotope (15N-18O) labeling technique and molecular methods. Results indicated that both traditional petroleum-based and emerging biodegradable MPs promoted sedimentary N2O production, whereas pathways varied. Biodegradable polylactic acid (PLA) MPs displayed greater promotion of N2O production than petroleum-based MPs, polyvinyl chloride (PVC) and polyethylene (PE), of which PLA promoted through nitrifier nitrification (NN) and heterotrophic denitrification (HD), PE through nitrifier denitrification and HD, and PVC through NN. By combining the analysis of N2O production rates with sediment chemical and microbiological properties, we demonstrated that the enrichment of nitrifying and denitrifying bacteria, as well as related functional genes directly and/or indirectly increased N2O production primarily by interacting with carbon and nitrogen substrates. Different response of nitrogen cycling microbes to MPs led to the difference in N2O increase pathways, of which nitrifying bacteria significantly enriched in all MPs treatments due to the niches provided by MPs. However, part of denitrifying bacteria significantly enriched in treatments containing PLA and PE MPs, which may serve as organic carbon substrates. This work highlights that the presence of MPs can promote sedimentary N2O production, and the emerging biodegradable MPs represented by PLA may have a greater potential to enhance estuarine N2O emissions and accelerate global climate change.
Assuntos
Microbiota , Petróleo , Bactérias/metabolismo , Carbono/metabolismo , Desnitrificação , Microplásticos , Nitrificação , Nitrogênio/metabolismo , Óxido Nitroso/metabolismo , Petróleo/metabolismo , Plásticos , Poliésteres/metabolismo , Cloreto de Polivinila/metabolismoRESUMO
Di-(2-ethylehxyl) phthalate (DEHP) is one of the most broadly representative phthalic acid esters (PAEs) used as a plasticizer in polyvinyl chloride (PVC) production, and is considered to be an endocrine-disrupting chemical. DEHP and its monoester metabolites are responsible for adverse effects on human health. An efficient DEHP-degrading bacterial strain Rhodococcus ruber YC-YT1, with super salt tolerance (0â»12% NaCl), is the first DEHP-degrader isolated from marine plastic debris found in coastal saline seawater. Strain YC-YT1 completely degraded 100 mg/L DEHP within three days (pH 7.0, 30 °C). According to high-performance liquid chromatographyâ»mass spectrometry (HPLC-MS) analysis, DEHP was transformed by strain YC-YT1 into phthalate (PA) via mono (2-ethylehxyl) phthalate (MEHP), then PA was used for cell growth. Furthermore, YC-YT1 metabolized initial concentrations of DEHP ranging from 0.5 to 1000 mg/L. Especially, YC-YT1 degraded up to 60% of the 0.5 mg/L initial DEHP concentration. Moreover, compared with previous reports, strain YC-YT1 had the largest substrate spectrum, degrading up to 13 kinds of PAEs as well as diphenyl, p-nitrophenol, PA, benzoic acid, phenol, protocatechuic acid, salicylic acid, catechol, and 1,2,3,3-tetrachlorobenzene. The excellent environmental adaptability of strain YC-YT1 contributed to its ability to adjust its cell surface hydrophobicity (CSH) so that 79.7â»95.9% of DEHP-contaminated agricultural soil, river water, coastal sediment, and coastal seawater were remedied. These results demonstrate that R. ruber YC-YT1 has vast potential to bioremediate various DEHP-contaminated environments, especially in saline environments.
Assuntos
Dietilexilftalato/análise , Dietilexilftalato/química , Disruptores Endócrinos/análise , Disruptores Endócrinos/química , Rhodococcus , Poluição da Água/análise , Infecções por Actinomycetales , Biodegradação Ambiental , Poluição Ambiental , Ésteres , Humanos , Ácidos Ftálicos/metabolismo , Plastificantes , Cloreto de Polivinila , Solo , Microbiologia do Solo , Microbiologia da ÁguaRESUMO
Surgical or traumatic brain injury often leads to loss of cerebral parenchyma but there is as yet no clinically effective strategy for neural regeneration. Collagen glycosaminoglycan (collagen-GAG, CG) scaffolds have previously been used in many tissues in vivo but have never been utilized in the brain. Using an animal model, we investigated the effects of the implantation of CG scaffold matrix following surgical brain trauma. Results indicated that implantation of CG scaffold could significantly promote functional recovery following surgical brain trauma. The CG scaffold was found to facilitate proliferation, differentiation and migration of endogenous neural precursor cells (NPCs) both in the intra-matrix zone (IMZ) and lesion boundary zone (LBZ). The tissue concentration of brain-derived neurotrophic factor (BDNF) and glia-derived neurotrophic factor (GDNF) in the cortex demonstrated a sustained increase after implantation of CG scaffold following surgical brain trauma. These results suggest that the utilization of CG scaffolds can be considered as a potential clinical strategy for tissue regeneration and functional recovery after brain injury.
Assuntos
Lesões Encefálicas/terapia , Colágeno/uso terapêutico , Glicosaminoglicanos/uso terapêutico , Regeneração Nervosa/fisiologia , Neurogênese/fisiologia , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Colágeno/química , Colágeno/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacologia , Humanos , Masculino , Teste de Materiais , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacosRESUMO
OBJECTIVE: IL-10 is a cytokine that plays a complex role in the control of immune responses. A case-control study was conducted to investigate the expression pattern of IL-10 in both serum and the whole unstimulated saliva from ethnic Chinese patients with oral lichen planus. METHOD AND MATERIALS: Seventy-nine Chinese patients with oral lichen planus were recruited for this study, and 41 healthy volunteers served as a control group. The levels of IL-10 and IFN-g in the serum and saliva were detected using enzyme-linked immunosorbent assay (ELISA). The IFN-g/IL-10 ratio was calculated by direct counting. RESULTS: The results demonstrated an expression profile of high IL-10 level and low IFN-g level and IFN-g/IL-10 ratio in both serum and saliva from oral lichen planus patients, compared to the controls. Saliva levels of IL-10 and IFN-g were positively correlated to their serum partners. No significant difference was found among subtypes of oral lichen planus. CONCLUSION: Elevation of IL-10 level might be involved in the pathogenesis of oral lichen planus, and saliva might be a substitute for serum to reflect the disease-related cytokine production in oral lichen planus patients.
Assuntos
Interleucina-10/análise , Líquen Plano Bucal/imunologia , Adulto , Análise de Variância , Povo Asiático , Estudos de Casos e Controles , Feminino , Expressão Gênica , Humanos , Interferon gama/análise , Interferon gama/biossíntese , Interferon gama/sangue , Interleucina-10/biossíntese , Interleucina-10/sangue , Líquen Plano Bucal/sangue , Líquen Plano Bucal/metabolismo , Líquen Plano Bucal/patologia , Masculino , Pessoa de Meia-Idade , Saliva/química , Estatísticas não ParamétricasRESUMO
The aim of the report is to increase the dentists', vigilance to the acquired immune deficiency syndrome (AIDS) by means of analyzing the oral exosyndrome and discussing the experience of diagnosis to 3 patients with AIDS. Vigilance to AIDS can make us to discover, diagnose and treat it in the early stage, and prevent us from transmission of the disease.