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INTRODUCTION: Odontogenic keratocysts (OKCs) are locally aggressive and have a high rate of recurrence, but the pathogenesis of OKCs is not fully understood. We aimed to investigate the serum metabolomic profile of OKCs and discover potential biomarkers. METHODS: Metabolomic analysis was performed on 42 serum samples from 22 OKC patients and 20 healthy controls (HCs) using gas chromatographyâmass spectrometry to identify dysregulated metabolites in the OKC samples. LASSO regression and receiver operating characteristic (ROC) curve analyses were used to select and validate metabolic biomarkers and develop diagnostic models. RESULTS: A total of 73 metabolites were identified in the serum samples, and 24 metabolites were dysregulated in the OKC samples, of which 4 were upregulated. Finally, a diagnostic panel of 10 metabolites was constructed that accurately diagnosed OKCs (sensitivity of 100%, specificity of 100%, area under the curve of 1.00). CONCLUSION: This study is the first to investigate the metabolic characteristics and potential metabolic biomarkers in the serum of OKC patients using GCâMS. Our study provides further evidence to explore the pathogenesis of OKC.
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Metabolômica , Cistos Odontogênicos , Humanos , Cistos Odontogênicos/diagnóstico , Biomarcadores , Cromatografia Gasosa-Espectrometria de Massas , Curva ROCRESUMO
Nitrate reduction in bio-electrochemical systems (BESs) has attracted wide attention due to its low sludge yields and cost-efficiency advantages. However, the high resistance of traditional electrodes is considered to limit the denitrification performance of BESs. Herein, a new graphene/polypyrrole (rGO/PPy) modified electrode is fabricated via one-step electrodeposition and used as cathode in BES for improving nitrate removal from wastewater. The formation and morphological results support the successful formation of rGO/PPy nanohybrids and confirm the part covalent bonding of Py into GO honeycomb lattices to form a three-dimensional cross-linked spatial structure. The electrochemical tests indicate that the rGO/PPy electrode outperforms the unmodified electrode due to the 3.9-fold increase in electrochemical active surface area and 6.9-fold decrease in the charge transfer resistance (Rct). Batch denitrification activity tests demonstrate that the BES equipped with modified rGO/PPy biocathode could not only achieve the full denitrification efficiency of 100% with energy recovery (15.9 × 10-2 ± 0.14 A/m2), but also favor microbial attach and growth with improved biocompatible surface. This work provides a feasible electrochemical route to fabricate and design a high-performance bioelectrode to enhance denitrification in BESs.
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Desnitrificação , Eletrodos , Grafite , Polímeros , Pirróis , Grafite/química , Polímeros/química , Pirróis/química , Técnicas Eletroquímicas/métodos , Fontes de Energia Bioelétrica , Nitratos/química , Carbono/química , Fibra de Carbono/químicaRESUMO
BACKGROUND: Oral squamous cell carcinoma (OSCC) is a prevalent malignancy affecting the head and neck region. The prognosis for OSCC patients remains unfavorable due to the absence of precise and efficient early diagnostic techniques. Metabolomics offers a promising approach for identifying distinct metabolites, thereby facilitating early detection and treatment of OSCC. OBJECTIVE: This review aims to provide a comprehensive overview of recent advancements in metabolic marker identification for early OSCC diagnosis. Additionally, the clinical significance and potential applications of metabolic markers for the management of OSCC are discussed. RESULTS: This review summarizes metabolic changes during the occurrence and development of oral squamous cell carcinoma and reviews prospects for the clinical application of characteristic, differential metabolites in saliva, serum, and OSCC tissue. In this review, the application of metabolomic technology in OSCC research was summarized, and future research directions were proposed. CONCLUSION: Metabolomics, detection technology that is the closest to phenotype, can efficiently identify differential metabolites. Combined with statistical data analyses and artificial intelligence technology, it can rapidly screen characteristic biomarkers for early diagnosis, treatment, and prognosis evaluations.
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Biomarcadores Tumorais , Carcinoma de Células Escamosas , Metabolômica , Neoplasias Bucais , Humanos , Neoplasias Bucais/metabolismo , Neoplasias Bucais/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Biomarcadores Tumorais/metabolismo , Saliva/metabolismo , Saliva/química , Detecção Precoce de Câncer , PrognósticoRESUMO
The manganese peroxidase (MnP) can degrade multiple mycotoxins including deoxynivalenol (DON) efficiently; however, the lignin components abundant in foods and feeds were discovered to interfere with DON catalysis. Herein, using MnP from Ceriporiopsis subvermispora (CsMnP) as a model, it was demonstrated that desired catalysis of DON, but not futile reactions with lignin, in the reaction systems containing feeds could be achieved by engineering MnP and supplementing with a boosting reactant. Specifically, two successive strategies (including the fusion of CsMnP to a DON-recognizing ScFv and identification of glutathione as a specific targeting enhancer) were combined to overcome the lignin competition, which together resulted into elevation of the degradation rate from 2.5% to as high as 82.7% in the feeds. The method to construct a targeting MnP and fortify it with an additional enhancer could be similarly applied to catalyze the many other mycotoxins with yet unknown responsive biocatalysts.
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Lignina , Micotoxinas , Tricotecenos , Lignina/metabolismo , Peroxidases/metabolismoRESUMO
The intricate and protracted process of dentin formation has been extensively explored, thanks to the significant advancements facilitated by the use of animal models and related techniques. Despite variations in their effectiveness, taking into account factors such as sensitivity, visibility, and reliability, these models or techniques are indispensable tools for investigating the complexities of dentin formation. This article focuses on the latest advances in animal models and related technologies, shedding light on the key molecular mechanisms that are essential in dentin formation. A deeper understanding of this phenomenon enables the careful selection of appropriate animal models, considering their suitability in unraveling the underlying molecular intricacies. These insights are crucial for the advancement of clinical drugs targeting dentin-related ailments and the development of comprehensive treatment strategies throughout the duration of the disease.
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Lignin is a crucial substance in the formation of the secondary cell wall in plants. It is widely distributed in various plant tissues and plays a significant role in various biological processes. However, the number of copies, characteristics, and expression patterns of genes involved in lignin biosynthesis in maize are not fully understood. In this study, bioinformatic analysis and gene expression analysis were used to discover the lignin synthetic genes, and two representative maize inbred lines were used for stem strength phenotypic analysis and gene identification. Finally, 10 gene families harboring 117 related genes involved in the lignin synthesis pathway were retrieved in the maize genome. These genes have a high number of copies and are typically clustered on chromosomes. By examining the lignin content of stems and the expression patterns of stem-specific genes in two representative maize inbred lines, we identified three potential stem lodging resistance genes and their interactions with transcription factors. This study provides a foundation for further research on the regulation of lignin biosynthesis and maize lodging resistance genes.
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Regulação da Expressão Gênica de Plantas , Genoma de Planta , Lignina , Zea mays , Zea mays/genética , Zea mays/metabolismo , Lignina/biossíntese , Lignina/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Genes de Plantas , Perfilação da Expressão Gênica/métodos , Parede Celular/metabolismo , Parede Celular/genética , Estudo de Associação Genômica Ampla , FenótipoRESUMO
Astaxanthin has 550 times more antioxidant activity than vitamin E, so it can scavenge free radicals in vivo and improve body immunity. However, the poor stability of astaxanthin becomes a bottleneck problem that limits its application. Herein, Haematococcus pluvialis (H. pluvialis) as a raw material was used to extract astaxanthin, and the optimal extraction conditions included the extraction solvent (EA:EtOH = 1:6, v/v), extraction temperature (60 °C), and extraction time (70 min). The extracted astaxanthin was then loaded using lecithin to form corresponding liposomes via the ethanol injection method. The results showed that the particle size and zeta potential of the prepared liposomes were 105.8 ± 1.2 nm and -38.0 ± 1.7 mV, respectively, and the encapsulation efficiency of astaxanthin in liposomes was 88.83%. More importantly, the stability of astaxanthin was significantly improved after being embedded in the prepared liposomes.
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Lipossomos , Xantofilas , Xantofilas/isolamento & purificação , Xantofilas/química , Lipossomos/química , Tamanho da Partícula , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Clorófitas/química , Clorofíceas/químicaRESUMO
Microplastics (MPs) have been shown to be a new type of pollutant in the oceans, with complex biofilms attached to their surfaces. Bacteria with quorum sensing (QS) systems are important participants in biofilms. Such bacteria can secrete and detect signal molecules. When a signal molecule reaches its threshold level, bacteria with QS systems can perform several biological functions, such as biofilm formation and antibiotic metabolite production. However, the ecological effects of QS bacteria in biofilm as MPs distribute globally with ocean currents are not to be elucidate yet. In this study, polypropylene and polyvinyl chloride were selected for on-site enrichment to acquire microplastics with biofilms. Eight culturable QS bacteria in the resulting biofilm were isolated by using biosensor assays, and their biodiversity was analyzed. The profiles of the N-acyl-homoserine lactones (AHLs) produced by these bacteria were analyzed by using thin-layer chromatography (TLC)-bioautography and gas chromatography and mass spectrometry (GC-MS). Biofilm-forming properties and several biological characteristics, such as bacteriostasis, algal inhibition, and dimethylsulfoniopropionate (DMSP) degradation, were explored along with QS quenching. Results showed that QS bacteria were mainly affiliated with class Alphaproteobacteria, particularly Rhodobacteraceae, followed by class Gammaproteobacteria. TLC-bioautography and GC-MS analyses revealed that seven AHLs, namely, C6-HSL, C8-HSL, 3-oxo-C6-HSL, 3-oxo-C8-HSL, 3-oxo-C10-HSL, and two unidentified AHLs were produced. The QS system equipped bacteria with strong biofilm-forming capacity and may contribute to the keystone roles of Rhodobacteraceae. In addition, QS bacteria may exacerbate the adverse environmental effects of MPs, such as inducing the misfeeding of planktons on MPs. This study elucidated the diversity of QS bacteria in MP-associated biofilms and provided a new perspective of the effect of key membrane-forming bacteria on the marine ecological environment.
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Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Percepção de Quorum , Acil-Butirolactonas , Bactérias , Biodiversidade , Biofilmes , Ecossistema , Microplásticos , Plásticos , AnimaisRESUMO
OBJECTIVES: This study aimed to determine the prevalence and independent risk factors of SDB, and explore its association with malocclusion among 6-11-year-old children in Shanghai, China. METHODS: A cluster sampling procedure was adopted in this cross-sectional study. Pediatric Sleep Questionnaire (PSQ) was applied to evaluate the presence of SDB. Questionnaires including PSQ, medical history, family history, and daily habits/environment were completed by parents under instruction, and oral examinations were implemented by well-trained orthodontists. Multivariable logistic regression was applied to identify independent risk factors for SDB. Chi-square tests and Spearman's Rank Correlation were used to estimate the relationship between SDB and malocclusion. RESULTS: A total of 3433 subjects (1788 males and 1645 females) were included in the study. The SDB prevalence was about 17.7%. Allergic rhinitis (OR 1.39, 95% CI 1.09-1.79), adenotonsillar hypertrophy (OR 2.39, 95% CI 1.82-3.19), paternal snoring (OR 1.97, 95% CI 1.53-2.53), and maternal snoring (OR 1.35, 95% CI 1.05-1.73) were independent risk factors for SDB. The SDB prevalence was higher in children with retrusive mandibles than in proper or excessive ones. No significant difference was observed in the correlation between SDB and lateral facial profile, mandible plane angle, constricted dental arch form, the severity of anterior overjet and overbite, degree of crowding and spacing, and the presence of crossbite and open bite. CONCLUSIONS: The prevalence of SDB in primary students in the Chinese urban population was high and highly associated with mandible retrusion. The independent risk factors included Allergic rhinitis, adenotonsillar hypertrophy, paternal snoring, and maternal snoring. More efforts should be made to enhance public education about SDB and related dental-maxillofacial abnormalities.
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Má Oclusão , Síndromes da Apneia do Sono , Masculino , Feminino , Humanos , Criança , Ronco/complicações , Ronco/epidemiologia , Estudos Transversais , China/epidemiologia , Síndromes da Apneia do Sono/complicações , Síndromes da Apneia do Sono/epidemiologia , Má Oclusão/complicações , Má Oclusão/epidemiologia , Fatores de Risco , Hipertrofia/complicações , Inquéritos e QuestionáriosRESUMO
Microplastics have been recognized as a novel niche for bacteria. However, studies have characterized the plastisphere microbial community in situ without exploring the microbial changes after transferring to other ecosystems. Here we focus on bacterial succession on typical microplastics (polypropylene and expanded polystyrene) and natural substrates (wood) after transferring from mariculture area to seagrass meadows system. Using high-throughput sequencing of 16 S rRNA, we found that alpha diversity significantly reduced after transferring and microplastics especially PP had significant separations on PCoA plots at different succession stages. The abundance and metabolic pathways of potential pathogen-associated microorganisms are significantly decreased. The relative abundance of xenobiotics biodegradation pathways was significantly lower and of energy metabolism pathways was significantly higher by comparing before and after transferring. Main environmental factors affecting microbial communities changed from nutrient characteristics to basic physicochemical properties after transferring. The succession times of the microbial communities of the three materials were different.
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Microbiota , Microplásticos , Microplásticos/metabolismo , Plásticos , Polipropilenos , Bactérias/metabolismoRESUMO
Limited permeability in solid tumors significantly restricts the anticancer efficacy of nanomedicines. Light-driven nanomotors powered by photothermal converting engines are appealing carriers for directional drug delivery and simultaneous phototherapy. Nowadays, it is still a great challenge to construct metal-free photothermal nanomotors for a programmable anticancer treatment. Herein, one kind of photoactivated organic nanomachines is reported with asymmetric geometry assembled by light-to-heat converting semiconducting polymer engine and macromolecular anticancer payload through a straightforward nanoprecipitation process. The NIR-fueled polymer engine can be remotely controlled to power the nanomachines for light-driven thermophoresis in the liquid media and simultaneously thermal ablating the cancer cells. The great manipulability of the nanomachines allows for programming of their self-propulsion in the tumor microenvironment for effectively improving cellular uptake and tumor penetration of the anticancer payload. Taking the benefit from this behavior, a programmed treatment process is established at a low drug dose and a low photothermal temperature for significantly enhancing the antitumor efficacy.
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Nanopartículas , Neoplasias , Sistemas de Liberação de Medicamentos , Humanos , Fototerapia , Polímeros , Microambiente TumoralRESUMO
The cavity electromechanical devices with radiation-pressure interaction induced Kerr-like nonlinearity are promising candidates to generate microwave frequency combs. We construct a silicon-nitride membrane based superconducting cavity electromechanical device and study two mechanical modes synergistic frequency combs. Around the threshold of intracavity field instability, we first show independent frequency combs with tooth spacing equal to each mechanical mode frequency. At the overlap boundaries of these two individual mechanical mode mediated instability thresholds, we observe hybridization of frequency combs based on the cavity field mediated indirect coupling between these two mechanical modes. The spectrum lines turn out to be unequally spaced, but can be recognized in combinations of the coexisting frequency combs. Beyond the boundary, the comb reverts to the single mode case, and which mechanical mode frequency will the tooth spacing be depends on the mode competition. Our work demonstrates mechanical mode competition enabled switchability of frequency comb tooth spacing and can be extended to other devices with multiple nonlinearities.
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The nonspecific binding of proteins with nanomaterials (NMs) is a dynamic reversible process including both protein adsorption and desorption parts, which is crucial for controlled release of protein drug loaded by nanocarriers. The nonspecific binding of proteins is susceptible to high temperature, whereas its underlying mechanism still remains elusive. Here, the binding behavior of human serum albumin (HSA) with an amino-terminated self-assembled monolayer (SAM)-coated gold (111) surface was investigated by using molecular dynamics (MD) simulations. HSA binds to the SAM surface through salt bridges at 300 K. As the temperature increases to 350 K, HSA maintains its native structure, while the salt bridges largely diminish owing to the considerable lateral diffusion of HSA on the SAM. Moreover, the interfacial water located between HSA and the SAM gets increased and prevents the reformation of the salt bridges of HSA with the SAM, which reduces the binding affinity of HSA. And HSA eventually desorbs from the SAM. The depiction of thermally induced spontaneous protein desorption enriches our understanding of reversible binding behavior of protein with NMs, and may provide new insights into the controlled release of protein drugs delivered by using nanocarriers under the regulation of high temperature.
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Nanopartículas Metálicas/química , Albumina Sérica Humana/química , Adsorção , Ouro/química , Temperatura Alta , Humanos , Membranas Artificiais , Simulação de Dinâmica Molecular , Eletricidade Estática , Compostos de Sulfidrila/química , Água/químicaRESUMO
BACKGROUND: Removal of self-expanding esophageal metal stents that have been implanted for a long time can be difficult and risky. PURPOSE: In this paper, we describe the use of the "inversion technique" under fluoroscopy for removal of self-expandable nitinol esophageal stents that have been placed for long periods and evaluate the effectiveness and safety of the method. METHODS: Retrospective analysis of patients who underwent removal of self-expanding nitinol esophageal stents by the inversion technique under fluoroscopy at our center. Demographic characteristics, type of esophageal stents, stent retention time, reasons for stent removal, and related complications were collected from the case records and analyzed. RESULTS: A total of 112 metal esophageal stents (62 fully covered esophageal stents and 50 partially covered esophageal stents) were extracted from the 107 patients included in the study. Indications for stent implantation were malignant esophageal stenosis (27 patients), benign esophageal stenosis (42 patients), and esophageal fistula (38 patients). Median duration of stent retention was 77 days (29-727 days). All stents were removed successfully without major complications such as esophageal rupture, massive hemorrhage, asphyxia, or cardiorespiratory arrest. CONCLUSION: Inversion technique under fluoroscopy appears to be a safe, effective, and quick procedure for removal of self-expanding nitinol esophageal stent after long-term placement.
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Estenose Esofágica , Ligas , Remoção de Dispositivo/métodos , Estenose Esofágica/etiologia , Fluoroscopia , Humanos , Metais , Estudos Retrospectivos , Stents/efeitos adversos , Resultado do TratamentoRESUMO
Enterococcus faecalis (E. faecalis) biofilm-associated persistent endodontic infections (PEIs) are one of the most common tooth lesions, causing chronic periapical periodontitis, root resorption, and even tooth loss. Clinical root canal disinfectants have the risk of damaging soft tissues (e.g., mucosa and tongue) and teeth in the oral cavity, unsatisfactory to the therapy of PEIs. Nanomaterials with remarkable antibacterial properties and good biocompatibility have been developed as a promising strategy for removing pathogenic bacteria and related biofilm. Herein, carbon dots (CDs) derived from fucoidan (FD) are prepared through a one-pot hydrothermal method for the treatment of PEIs. The prepared FDCDs (7.15 nm) with sulfate groups and fluorescence property are well dispersed and stable in water. Further, it is found that in vitro FDCDs display excellent inhibiting effects on E. faecalis and its biofilm by inducing the formation of intracellular and extracellular reactive oxygen species and altering bacterial permeability. Importantly, the FDCDs penetrated the root canals and dentinal tubules, removing located E. faecalis biofilm. Moreover, the cellular assays show that the developed FDCDs have satisfactory cytocompatibility and promote macrophage recruitment. Thus, the developed FDCDs hold great potential for the management of PEIs.
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Enterococcus faecalis , Irrigantes do Canal Radicular , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Carbono , Polissacarídeos , Irrigantes do Canal Radicular/farmacologia , Irrigantes do Canal Radicular/uso terapêutico , Hipoclorito de Sódio/farmacologia , Hipoclorito de Sódio/uso terapêuticoRESUMO
Impaction of multiple maxillary anterior teeth is a rare condition; when it occurs, it impacts the patient's chewing function and smile esthetics, and it has always been problematic for clinicians. This case report presents an 11-year-old girl with impaction of 3 adjacent maxillary anterior teeth, including labiopalatally oriented maxillary right central and lateral incisors and a mesially inclined maxillary right canine. These 3 impacted and stacked teeth were sequentially aligned after surgical exposure and orthodontic traction, and the surrounding dentigerous cyst healed simultaneously. Precise and delicate biomechanics will control root movement and prevent root collision. Gate spring, a novel torquing auxiliary, was used for highly efficient root torque movements of the previously impacted incisors. After 32-month treatment, the patient's occlusion and esthetics greatly improved.
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Coxsackievirus A6 (CV-A6) has been associated with increasingly occurred sporadic hand-foot-mouth disease (HFMD) cases and outbreak events in many countries. In order to understand epidemiological characteristics of CV-A6, we collected the information describing HFMD caused by CV-A6 to describe the detection rate, severe rate and onychomadesis rate, which is defined as one or more nails defluvium, caused by CV-A6 from 2007 to 2017. The results showed that there was an outbreak of CV-A6 every other year, and overall trend of the epidemic of CA6-associated HFMD was increasing in China. The detection rate of CV-A6 in other countries was 32.0% (95% CI: 25.0%~40.0%) before 2013 and 28.0% (95% CI: 20.0%~36.0%) after 2013, respectively. Although the severe rate of HFMD caused by CV-A6 was low (0.10%, 95% CI: 0.01%~0.20%), CV-A6 can cause a high incidence of onychomadesis (28.0%, 95%CI: 21.9%-34.3%). Thus, it would be worthwhile to research and develop an effective multivalent vaccine for CV-A6 to achieve a more powerful prevention of HMFD.
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Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Comorbidade , Surtos de Doenças , Suscetibilidade a Doenças , Enterovirus Humano A/classificação , Saúde Global , Doença de Mão, Pé e Boca/diagnóstico , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Incidência , Epidemiologia Molecular , Vigilância em Saúde PúblicaRESUMO
Two novel sulfonic functionalized coordination polymers (CPs) {[Cd1.5(dimb)(5-sip)(H2O)3]·3H2O}n (1, dimb = 1,4-di(1H-imidazol-1-yl)butane) and [Co2(iptz)(Hiptz)(5-sip)(H2O)]·4H2O (2, Hiptz = 1-(4-(1H-imidazole-5-yl)phenyl)-1H-1,2,4-triazole) were acquired via different metal(II) salts reacting with the mixed ligands containing 1-(4-(1H-imidazole-5-yl)phenyl)-1H-1,2,4-triazole, 1,4-di(1H-imidazol-1-yl)butane and sodium 5-sulfoisophthalate (NaH2sip), respectively. Furthermore, the complex 1 based on Cd(II) could be utilized as the luminescent senor for picric acid (PA) detection in water. In bio-research, compounds 1 and 2 treatment effect on chronic periodontitis was assessed and the specific mechanism was discussed. First of all, the RT-PCR was performed to measure the HmuY and fimA genes relative expression level in P.gingivalis after treated by compounds 1 and 2. Then, the TNF-α and IL-6 content in the fluid of gingival crevicular after compounds treatment was determined with ELISA detection kit.
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Periodontite Crônica/tratamento farmacológico , Periodontite Crônica/metabolismo , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Interleucina-6/metabolismo , Polímeros/química , Fator de Necrose Tumoral alfa/metabolismo , Complexos de Coordenação/uso terapêutico , Ligantes , Elementos de Transição/químicaRESUMO
Extracellular polymeric substances (EPS) are considered crucial components in the formation of microbial aggregates such as biofilms, flocs and granules. However, the role of EPS in sludge aggregation is still unclear. In this study, the differences in EPS characteristics of anammox granular sludge (AG), anammox floc sludge (AF) and activated floc sludge (AS) were investigated to clarify its role in granular aggregation. The results showed that the flocculation ability of EPS extracted from AG (62.8 ± 2.3%) was notably higher than that of EPS extracted from AF (35.7 ± 1.7%) and AS (17.3 ± 1.5%). The zeta potential and hydrophobicity of EPS showed the same tendency. In addition, the PN/PS ratio of AG, AF and AS were 7.66, 4.62 and 3.93, respectively. FTIR, XPS and 3D-EEM fluorescence spectra results revealed that anammox granular sludge has a higher ratio of hydrophobic groups, α-helixs/(ß-sheets and random coils), intermolecular hydrogen bonds, and aromatic amino acids, and a lower ratio of electronegative groups. Anammox granular sludge exhibited high aggregation ability, because its EPS had higher zeta potential, hydrophobicity and intermolecular hydrogen bond ratio. This work provides a better understanding of the high aggregation ability of anammox granules and a theoretical basis for improving granules proportion and retention ability of microbes in reactor system.
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Oxidação Anaeróbia da Amônia , Reatores Biológicos , Polímeros/química , Esgotos , Anaerobiose , Desenho de Equipamento , Matriz Extracelular de Substâncias Poliméricas , Floculação , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Nitrogênio , Espectroscopia Fotoeletrônica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
A magnetic solid-phase extraction (MSPE) technique coupled with high performance liquid chromatography (HPLC) was developed and used for bioaccumulation investigation of bisphenol A (BPA) in HepG2 cells and zebrafishes. Cobalt magnetic polystyrene microsphere derived carbon (C-Co@PST) as an adsorbent was prepared by in situ polymerization reaction and further annealing treatment. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectrometry, X-ray photoelectron spectroscopy and X-ray diffraction were employed to confirm successful synthesis of C-Co@PST. A series of extraction parameters including the amount of the sorbent, the type of elute, extraction time and elution time were investigated to achieve high extraction efficiency. C-Co@PST based MSPE combined with HPLC was successfully established for bioaccumulation research of BPA in living creatures. It was found that the bioconcentration values of BPA in HepG2 cells underwent an increase, then a decrease, and finally reached an equilibrium level of 11.60 µg kg-1 at 8 h. The concentration of BPA in zebrafishes increased ranging from 6.05 µg kg-1 to 31.84 µg kg-1 over a culture time from 1 h to 12 h. Furthermore, linear and exponential models were employed to analyse the bioconcentration variation of BPA in organisms over the exposure time. Mathematical models have been developed to predict the transfer characteristics of BPA.