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Tau is a microtubule-associated protein that forms insoluble filaments that accumulate as neurofibrillary tangles in neurodegenerative diseases such as Alzheimer's disease and other related tauopathies. A relationship between abnormal Tau accumulation and ubiquitin-proteasome system impairment has been reported. However, the molecular mechanism linking Tau accumulation and ubiquitin proteasome system (UPS) dysfunction remains unclear. Here, we show that overexpression of wild-type or mutant (P301L) Tau increases the abundance of polyubiquitinated proteins and activates the autophagy-lysosome pathway in mammalian neuronal cells. Previous studies found that PTK2 inhibition mitigates toxicity induced by UPS impairment. Thus, we investigated whether PTK2 inhibition can attenuate Tau-induced UPS impairment and cell toxicity. We found that PTK2 inhibition significantly reduces Tau-induced death in mammalian neuronal cells. Moreover, overexpression of WT or mutant Tau increased the phosphorylation levels of PTK2 and p62. We also confirmed that PTK2 inhibition suppresses Tau-induced phosphorylation of PTK2 and p62. Furthermore, PTK2 inhibition significantly attenuated the climbing defect and shortened the lifespan in the Drosophila model of tauopathy. In addition, we observed that phosphorylation of p62 is markedly increased in Alzheimer's disease patients with tauopathies. Taken together, our results indicate that the UPS dysfunction induced by Tau accumulation might contribute directly to neurodegeneration in tauopathies and that PTK2 could be a promising therapeutic target for tauopathies.
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Doença de Alzheimer , Tauopatias , Animais , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Tauopatias/metabolismo , Ubiquitinas/metabolismo , Mamíferos/metabolismoRESUMO
Oligonucleotides of adenine (A20), guanine (G20), cytosine (C20), thymine (T20), cytosine-guanine ((CG)20), and adenine-thymine ((AT)20) were investigated as model compounds for ice recrystallization inhibition (IRI). Dehydroxy uracil (dU20), U20, and T20 were also compared to investigate the effect of minute changes in the hydrophobicity of the oligonucleotides on the IRI activity. Among the oligonucleotides considered in this study, T20 exhibited the best performance for IRI. In addition, the degree of polymerization of oligothymines varied over 5, 10, 20, 30, 50, and 100, and T20 was found to be the most effective for IRI. The IRI mechanism was investigated by comparing U20 and T20, which exhibited the lowest and highest IRI activity, respectively, among the oligonucleotides for their dynamic ice-shaping, thermal hysteresis, and ice nucleation inhibition. Little or no dynamic ice-shaping activity and small thermal hysteresis were observed for both nucleotides. All of the findings suggest that not the ice-polymer adhesion but the hydrophobic interactions of T20 in the interface layer might interfere with the water deposition on the ice crystal surfaces and contribute to the IRI activity of the T20 oligonucleotide.
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Gelo , Oligonucleotídeos , Timina , Cristalização , Água , Proteínas Anticongelantes/químicaRESUMO
Biofilms are surface-associated microbial clusters embedded in extracellular polymeric substances. Biofilms formed on food-contact surfaces create challenges for the food industry due to their increased tolerance to antimicrobial agents and disinfectants. This study aimed to evaluate the effect of the biofilm maturation period on their resistance to gaseous ClO2. Listeria monocytogenes, Salmonellaserotype Typhimurium, and Escherichia coli O157:H7 biofilms formed on stainless steel (SS) and high-density polyethylene (HDPE) surfaces were investigated. The total cell mass and protein content significantly increased (P < .05) between the second and the fifth day of maturation, and the biofilms' resistance to gaseous ClO2 increased as they matured. Generally, the cell counts of 0-day-old L. monocytogenes, Salm. Typhimurium, and E. coli O157:H7 biofilms on SS and HDPE reduced below the detection limit (0.48 log CFU/cm2) within 5 min. The cell counts of 2-day-old biofilms of the three pathogens were reduced by 6.22 to over 7.52 log, while those of 5-day-old biofilms were reduced by 3.64 to over 6.34 log after 20 min of treatment with 30 ppmv of gaseous ClO2. Therefore, as resistance increases with biofilm maturation, daily gaseous ClO2 treatment would maximize the antimicrobial efficacy of the cleaning strategy against biofilms.
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Anti-Infecciosos , Escherichia coli O157 , Gases/farmacologia , Contagem de Colônia Microbiana , Polietileno/farmacologia , Microbiologia de Alimentos , Biofilmes , Anti-Infecciosos/farmacologiaRESUMO
The aim of the present study was to elucidate the correlation between the International Caries Detection and Assessment System (ICDAS) and the Snyder caries activity test (SCAT) for the assessment of early dental caries in preschool children. Dental health status of 153 children aged 3-5 years was evaluated by oral examination. The ICDAS stage (enamel opacity stage to cavitated dentine caries stage (stages 1-6)) was assigned based on the evaluation of each tooth surface by a trained dentist based on the number of decayed (d) and filled teeth (ft). In this study, scores of d3-6t (t, teeth), d3-6s (s, tooth surface), d3-6ft and d3-6fs were the cut-off points for enamel caries, set to ICDAS code 3 (d3). SCAT score was assigned based on the acid production level of lactic acid bacteria in plaque (scores: 1-4). Linear correlation analysis was used to determine the correlation between ICDAS and SCAT scores. The proportion of children for each of the dental caries status were as follows: d0, 46.4%; d1-2, 28.1%; d3-4, 9.8%; d5-6, 15.7%. Regarding SCAT scores, 30%, 30.1%, 26.8% and 12.4% children had no, mild, moderate and severe caries activity, respectively. The d3-6t, d3-6s, d3-6ft and d3-6fs indices increased with age and were 0.56, 0.82, 2.03 and 5.05, respectively. Children with a higher SCAT score had higher ICDAS scores (p < 0.05). Our findings suggest that a combination of ICDAS and SCAT scores is beneficial for diagnosing caries progression and highly active caries. Early childhood caries should be managed early to prevent the enamel opacity stage to progress to cavitation.
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Cárie Dentária , Dente , Humanos , Pré-Escolar , Cárie Dentária/diagnóstico , Estudos Transversais , Suscetibilidade à Cárie DentáriaRESUMO
Brain mosaic mutations are a major cause of refractory focal epilepsies with cortical malformations such as focal cortical dysplasia, hemimegalencephaly, malformation of cortical development with oligodendroglial hyperplasia in epilepsy, and ganglioglioma. Here, we collected cerebrospinal fluid (CSF) during epilepsy surgery to search for somatic variants in cell-free DNA (cfDNA) using targeted droplet digital polymerase chain reaction. In 3 of 12 epileptic patients with known somatic mutations previously identified in brain tissue, we here provide evidence that brain mosaicism can be detected in the CSF-derived cfDNA. These findings suggest future opportunities for detecting the mutant allele driving epilepsy in CSF. ANN NEUROL 2021;89:1248-1252.
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Encéfalo , Ácidos Nucleicos Livres/líquido cefalorraquidiano , Epilepsia Resistente a Medicamentos/genética , Adolescente , Criança , Pré-Escolar , Epilepsia Resistente a Medicamentos/líquido cefalorraquidiano , Feminino , Humanos , Lactente , Masculino , MutaçãoRESUMO
This study evaluated the chlorine dioxide (ClO2) gas mediated inactivation of the biofilm cells of foodborne pathogens on food contact surfaces. Biofilm cells of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes were developed on stainless steel (SS) and high density polyethylene (HDPE) coupon surfaces, and 5-day-old biofilms were treated with ClO2 gas at 60 and 90% relative humidity (RH) for up to 20 min. With an increase in gas concentration and treatment time, significant differences (p < 0.05) were observed between reduction levels under different RH conditions. Treatment with 50 ppmv of ClO2 gas (60% RH) for 20 min resulted in log reductions from 2.08 to 4.62 and 2.08 to 4.41 of the biofilm cells of three pathogens on SS and HDPE surfaces, respectively. The levels of biofilm cells of E. coli O157:H7, S. Typhimurium, and L. monocytogenes on SS and HDPE surfaces were reduced to below the detection limit (0.48 log CFU/cm2) within 15, 20, and 20 min, respectively, when exposure to 50 ppmv of ClO2 gas at 90% RH.
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BACKGROUND: Cytoplasmic inclusions of transactive response DNA binding protein of 43 kDa (TDP-43) in neurons and astrocytes are a feature of some neurodegenerative diseases, such as frontotemporal lobar degeneration with TDP-43 (FTLD-TDP) and amyotrophic lateral sclerosis (ALS). However, the role of TDP-43 in astrocyte pathology remains largely unknown. METHODS: To investigate whether TDP-43 overexpression in primary astrocytes could induce inflammation, we transfected primary astrocytes with plasmids encoding Gfp or TDP-43-Gfp. The inflammatory response and upregulation of PTP1B in transfected cells were examined using quantitative RT-PCR and immunoblot analysis. Neurotoxicity was analysed in a transwell coculture system of primary cortical neurons with astrocytes and cultured neurons treated with astrocyte-conditioned medium (ACM). We also examined the lifespan, performed climbing assays and analysed immunohistochemical data in pan-glial TDP-43-expressing flies in the presence or absence of a Ptp61f RNAi transgene. RESULTS: PTP1B inhibition suppressed TDP-43-induced secretion of inflammatory cytokines (interleukin 1 beta (IL-1ß), interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-α)) in primary astrocytes. Using a neuron-astrocyte coculture system and astrocyte-conditioned media treatment, we demonstrated that PTP1B inhibition attenuated neuronal death and mitochondrial dysfunction caused by overexpression of TDP-43 in astrocytes. In addition, neuromuscular junction (NMJ) defects, a shortened lifespan, inflammation and climbing defects caused by pan-glial overexpression of TDP-43 were significantly rescued by downregulation of ptp61f (the Drosophila homologue of PTP1B) in flies. CONCLUSIONS: These results indicate that PTP1B inhibition mitigates the neuronal toxicity caused by TDP-43-induced inflammation in mammalian astrocytes and Drosophila glial cells.
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Astrócitos/metabolismo , Proteínas de Ligação a DNA/biossíntese , Mediadores da Inflamação/metabolismo , Degeneração Neural/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/biossíntese , Animais , Animais Geneticamente Modificados , Astrócitos/patologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Drosophila , Expressão Gênica , Mediadores da Inflamação/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Degeneração Neural/genética , Degeneração Neural/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/genéticaRESUMO
Based on the characteristic properties like strong fluorescence and high photostability, DNA-templated silver nanoclusters (DNA-AgNCs) were utilized to detect Klenow fragment exo- (KF-) activity and to monitor its inhibition by daidzein. In this study, fluorescence intensity is linearly correlated for KF- concentration ranging from 0 to 2.0 U/mL, with a minimum detectable concentration of 0.05 U/mL. In addition, KF- inhibition was monitored by changes in fluorescence intensity with increasing daidzein concentration gradually.
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Técnicas Biossensoriais , Nanopartículas Metálicas , DNA , DNA Polimerase Dirigida por DNA , Prata , Espectrometria de FluorescênciaRESUMO
Fluorescence assays have been developed to detect biomolecules using DNA-templated silver nanoclusters (DNA-AgNCs) utilizing their unique physical and optical properties. This study was designed to detect single-mismatched DNA by the hybridization of target DNA to template DNA either before or after DNA-AgNCs synthesis. The results showed that the detection specificity of a single-mismatched DNA was clearly enhanced when the target DNA (cDNA) was hybridized to template DNA prior to DNA-AgNCs synthesis compared with cDNA hybridization subsequent to DNA-AgNCs synthesis.
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Pareamento Incorreto de Bases , DNA/análise , Sequências Repetidas Invertidas , Nanopartículas Metálicas/química , Prata/química , DNA/química , Espectrometria de FluorescênciaRESUMO
BACKGROUND: Oral health greatly affects well-being throughout the different stages of life from childhood to late adulthood. Loss of teeth due to poor oral health hinders mastication, leading to poor nutrition absorption, and affects pronunciation and aesthetics, leading to interpersonal difficulties. As social activities become limited, a sense of isolation and loneliness, stress, and depression grows while happiness decreases. This study aimed to examine the association of stress, depression, and suicidal ideation with oral health status and oral functions in a large nationwide sample of Korean adults aged 35 years or more. METHODS: The sample comprised 15,716 adults, selected using a rolling survey sampling method and data were extracted from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES) (2010-2012). Participants were interviewed about their self-evaluation of health including oral health status and mental health, such as stress, depression, and suicidal ideation. Data from 11,347 adults were finally selected after excluding participants with missing answers. The dependent variables were stress, depression, and suicidal ideation. The independent variables were gender, age, household income, education, smoking, drinking, oral health perception, chewing, and speaking. Complex samples logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Participants met the criteria for stress (25.4%), depression (13.0%), and suicidal ideation (13.9%). Subjective oral health status was not significantly associated with stress, depression, and suicidal ideation. However, the presence of very uncomfortable chewing problems was significantly associated with stress (OR = 2.294, 95% CI = 1.41, 3.72), depression (OR = 3.232, 95% CI = 1.97, 5.31), and suicidal ideation (OR = 2.727, 95% CI = 1.58, 4.72). The presence of very uncomfortable speaking problems was significantly associated with stress (OR = 1.592, 95% CI = 1.13, 2.24) but not significantly associated with depression and suicidal ideation. CONCLUSIONS: Oral functional problems including chewing and speaking difficulties can be associated with mental health. It is necessary to develop oral health promotion programs for adults and help them maintain a good quality of life and mental health.
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Depressão/epidemiologia , Saúde Bucal , Estresse Psicológico/epidemiologia , Ideação Suicida , Adulto , Idoso , Depressão/complicações , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Bucal/estatística & dados numéricos , República da Coreia/epidemiologia , Estresse Psicológico/complicaçõesRESUMO
BACKGROUND: The aim of this study was to analyse the prevalence and severity of dental caries among Korean children aged 8 and 12 years over a period of 12 years by determining the number of decayed, missing, and filled teeth (DMFT) and the Significant Caries index (SiC index). METHODS: Stratified cluster-sampled data from the National Oral Health Survey conducted from 2000 to 2012 were analysed. In 2000, 2006, and 2012, a total of 2397, 2650, and 9601 children aged 8 and 12 years were examined, respectively. The children's oral health status, including the number of DMFT and fissures sealed teeth, was examined and recorded. The SiC index was calculated according to the child's residential district. RESULTS: Over the 12-year period, the percentages of caries-free children aged 8 and 12 years increased from 26.0 to 42.7 % and from 53.4 to 69.6 %, respectively. The percentages of children aged 8 and 12 years with sealed teeth in 2012 were 62.1 and 62.5 %, respectively, more than triple the rates in 2000. The mean DMFT values of children aged 8 and 12 years decreased from1.04 to 0.67 and from 2.86 to 1.84, respectively. The SiC index of children aged 8 and 12 years also decreased from 2.73 to 1.97 and from 6.13 to 4.51, respectively. The rate of reduction in DMFT among 8- and 12-year-old children in the second 6 years of the observation period was lower than that in the first 6 years. CONCLUSIONS: A remarkable decline in dental caries of 8- and 12-year-old Korean children was observed over the 12-year study period. The mean DMFT values and SiC index of children aged 8 and 12 years decreased. The reduction rate between 2000 and 2006 was higher than that between 2006 and 2012.
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Cárie Dentária/epidemiologia , Inquéritos de Saúde Bucal , Criança , Índice CPO , Assistência Odontológica , Humanos , Prevalência , República da Coreia/epidemiologiaRESUMO
Graphene oxide (GO) has a large surface-to-volume ratio and hydrophobic hexagonal rings that can interact with biomolecules. Single-stranded DNA adsorbs strongly to the surface of GO via hydrophobic interactions. GO has been used in optical biosensors and biomedical platforms for the detection of DNA, proteins, and small molecules. This study was designed to measure the adsorption of double-stranded DNA (dsDNA) onto GO according to DNA length, salt concentration, and pH of the reaction. Results showed that dsDNA molecules were adsorbed progressively as the pH changed from 6.0 to 4.0. At high pH, dsDNA adsorption was enhanced by the presence of MgCl2 rather than NaCl. Desorption of DNA from GO, with triton X-100 led to the rapid release of DNA from GO in the presence of MgCl2.
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DNA/química , Grafite/química , Cloreto de Magnésio/química , Óxidos/química , Cloreto de Sódio/química , Adsorção , Concentração de Íons de HidrogênioRESUMO
A phase I trial of first-line vorinostat, an orally bio-available histone deacetylase inhibitor, in combination with capecitabine plus cisplatin (XP) was performed to assess recommend phase II trial dose in patients with advanced gastric cancer. Five dose levels of three-weekly vorinostat-XP were tested; vorinostat was dosed at 300-400 mg once daily on Days 1-14, capecitabine at 800-1,000 mg/m(2) twice daily on Days 1-14, and cisplatin at 60-80 mg/m(2) on Day 1. To assess the pharmacodynamics of vorinostat, histone H3 acetylation was assessed in peripheral blood mononuclear cells before the study treatment and at Day 8 of cycle 1. In total, 30 patients with unresectable or metastatic gastric adenocarcinoma were included. Dose-limiting toxicities were thrombocytopenia, fatigue, stomatitis, and anorexia. The following doses were recommended for phase II trial: 400 mg of vorinostat once daily, 1,000 mg/m(2) of capecitabine twice daily, and 60 mg/m(2) of cisplatin. The most common grade 3-4 toxicities were neutropenia (47 %), anorexia (20 %), thrombocytopenia (17 %), and fatigue (13 %). In overall, response rate was 56 % (95 % confidence interval [CI]: 32-81). With a median follow-up of 14.1 months, the median progression-free survival and overall survival were 7.1 months (95 % CI: 3.8-10.3) and 18.0 months (95 % CI: 4.8-31.1), respectively. The change in H3 acetylation after treatment with vorinostat correlated significantly with the vorinostat dose (300 vs. 400 mg/day) and the baseline level of H3 acetylation before treatment. Three-weekly vorinostat-XP regimen is feasible and recommended for further development in advanced gastric cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Gástricas/tratamento farmacológico , Acetilação , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/análogos & derivados , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/efeitos adversos , Histonas/metabolismo , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Ácidos Hidroxâmicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/metabolismo , VorinostatRESUMO
Mobilization with movement (MWM) and myofascial release (MFR) are treatment techniques that increase ankle dorsiflexion range of motion (DFROM). Manual lymphatic drainage (MLD) facilitates waste drainage and improves soft tissue tension in peripheral tissues. To date, no studies have investigated how the combination of MLD, MWM, and MFR influences the human body. The purpose of this study is to determine how the combination of MLD, MWM, and MFR affects DFROM and balance ability. We randomly assigned 16 individuals (26 feet) to one of three groups: MWM-MFR (MR), MWM-MLD (MD), or MWM-MFR-MLD (MRD) intervention. To confirm the intervention effect of each group, DFROM was assessed using a modified lunge test, and dynamic balance was measured using a modified star excursion balance test. In the results, differences were found between the MR and MRD groups in PL and mGCM activities in the 1 section (p = 0.008, p = 0.036) and between the MD and MRD groups in mGCM activity in the 4 and 5 sections (p = 0.049, p = 0.004). We suggest that the application of MRD is the most effective intervention for increasing muscle activation of the PL and mGCM during the modified star excursion balance test.
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A biofilm is a three-dimensional microbial community, which is difficult to completely control with a typical sanitizer owing to its complex structure. The aim of this study was to establish a system for the combined treatment of biofilms with 10 ppmv gaseous chlorine dioxide (ClO2) and antimicrobial agents (2% citric acid, 2% hydrogen peroxide [H2O2], and 100 ppm peracetic acid [PAA]), and to investigate the synergistic microbicidal efficacy of the combination treatments to inactivate Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7 in biofilms. The antimicrobial agents were aerosolized using a humidifier on top of a chamber to achieve a relative humidity of 90% (within a range of ±2%). While biofilm treatment with the aerosolized antimicrobial agents for 20 min inactivated approximately 1 log CFU/cm2 (0.72-1.26 log CFU/cm2) of the pathogens and the gaseous ClO2 gas treatment for 20 min inactivated <3 log CFU/cm2 (2.19-2.77 log CFU/cm2), combination treatment with citric acid, H2O2, and PAA for 20 min achieved microbial reductions of 2.71-3.79, 4.56-5.12, and 4.45-4.67 log CFU/cm2, respectively. Our study demonstrates that foodborne pathogens in biofilms can be inactivated by combining gaseous ClO2 treatment with aerosolized antimicrobial agents. The results of this study provide baseline data for the food industry to help control foodborne pathogens in biofilms on inaccessible surfaces.
Assuntos
Anti-Infecciosos , Desinfetantes , Listeria monocytogenes , Desinfetantes/farmacologia , Contagem de Colônia Microbiana , Gases , Microbiologia de Alimentos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , BiofilmesRESUMO
Several studies have demonstrated that nuclear magnetic resonance (NMR) metabolic profiles can differentiate patients with caries from healthy individuals; however, these studies only identified individual metabolites. The present study aimed to identify a salivary metabolite biomarker panel for the diagnosis of early childhood caries (ECC). Saliva samples from children with and without caries were analyzed using NMR spectroscopy. Multivariate and univariate analyses were performed to identify the discriminating metabolites. Selected metabolites were further evaluated and used to detect ECC. The saliva samples of children with ECC were characterized based on the increased levels of formate, glycerophosphocholine, and lactate and reduced levels of alanine, glycine, isoleucine, lysine, proline, and tyrosine. The levels of these metabolites were significantly different from those in the control in the ECC subgroup according to caries severity and correlated with the number of decayed and filled teeth or surfaces. Subsequently, an optimal salivary metabolite biomarker panel comprising formate, lactate, proline, and glycine was developed. This panel exhibited a better diagnostic performance for ECC than a single metabolite. These results demonstrate that salivary metabolic signatures can reflect oral conditions associated with dental caries, thereby emphasizing the importance of distinct salivary metabolic profiles as potential biomarkers of ECC.
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The increased interest in outdoor activities has prompted the demand for water-repellent fabrics that can withstand various environmental factors. In this study, the water repellency and physical properties, namely thickness, weight, tensile strength, elongation, and stiffness, of cotton woven fabrics were analyzed according to various treatments with different types of household water-repellent agents and number of coating layers. Fluorine-, silicone-, and wax-based water-repellent agents were coated on cotton woven fabrics once, thrice, and five times. Thickness, weight, and stiffness increased with the number of coating layers, which may reduce comfort. These properties increased minimally for the fluorine- and silicone-based water-repellent agents, whereas they considerably increased for the wax-based water-repellent agent. The fluorine-based water-repellent agent had a low water repellency rating of 2.2 even after five coating layers, and the silicone-based water-repellent agent had a higher rating of 3.4 with the same five coating layers. Meanwhile, the wax-based water-repellent agent had the highest water repellency rating of 5 even with only one coating layer, which was maintained with repeated coatings. Therefore, fluorine- and silicone-based water-repellent agents minimally altered the fabric properties even with repeated coatings; multiple coating layers, especially five or more layers for the fluorine-based water-repellent agent, are recommended to attain excellent water repellency. Conversely, one coating layer of the wax-based water-repellent agent is recommended to retain the comfort of the wearer.
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Flúor , Têxteis , Fenômenos Físicos , Silicones , ÁguaRESUMO
This study presents a method for discriminating the geographical origin of dried chili peppers using femtosecond laser ablation-inductively coupled plasma-mass spectrometry (fsLA-ICP-MS) and multivariate analysis, such as orthogonal partial least squares discriminant analysis (OPLS-DA), heatmap analysis, and canonical discriminant analysis (CDA). Herein, 102 samples were analyzed for the content of 33 elements using optimized conditions of 200 Hz (repetition rate), 50 µm (spot size), and 90% (energy). Significant differences in count per second (cps) values of the elements were observed between domestic and imported peppers, with variations of up to 5.66 times (133Cs). The OPLS-DA model accuracy achieved an R2 of 0.811 and a Q2 of 0.733 for distinguishing dried chili peppers of different geographical origins. The variable importance in projection (VIP) and s-plot identified elements 10 and 3 as key to the OPLS-DA model, and in the heatmap, six elements were estimated to be significant in discriminating between domestic and imported samples. Furthermore, CDA showed a high accuracy of 99.02%. This method can ensure food safety for consumers, and accurately determine the geographic origin of agricultural products.
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Consumption of aflatoxin-contaminated food can cause severe illness when consumed by humans or livestock. Because the mycotoxin frequently occurs in cereal grains and other agricultural crops, it is crucial to develop portable devices that can be used non-destructively and in real-time to identify aflatoxin-contaminated food materials during early stages of harvesting or processing. In this study, an aflatoxin detection method was developed using a compact Raman device that can be used in the field. Data were obtained using maize samples naturally contaminated with aflatoxin, and the data were analyzed using a machine learning method. Of the multiple classification models evaluated, such as linear discriminant analysis (LDA), linear support vector machines (LSVM), quadratic discriminant analysis (QDA), and quadratic support vector machines and spectral preprocessing methods, the best classification accuracy was achieved at 95.7% using LDA in combination with Savitzky-Golay 2nd derivative (SG2) preprocessing. Partial least squares regression (PLSR) models demonstrated a close-range accuracy within the scope of standard normal variate (SNV) and multiplicative scatter correction (MSC) preprocessing methods, with determination of coefficient values of R2C and R2V of 0.9998 and 0.8322 respectively for SNV, and 0.9916 and 0.8387 respectively for MSC. This study demonstrates the potential use of compact and automated Raman spectroscopy, coupled with chemometrics and machine learning methods, as a tool for rapidly screening food and feed for hazardous substances at on-site field processing locations.