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Jasmonic acid (JA) and ethylene (ET) signaling modulate plant defense against necrotrophic pathogens in a synergistic and interdependent manner, while JA and ET also have independent roles in certain processes, e.g. in responses to wounding and flooding, respectively. These hormone pathways lead to transcriptional reprogramming, which is a major part of plant immunity and requires the roles of transcription factors. ET response factors are responsible for the transcriptional regulation of JA/ET-responsive defense genes, of which ORA59 functions as a key regulator of this process and has been implicated in the JA-ET crosstalk. We previously demonstrated that Arabidopsis (Arabidopsis thaliana) GDSL LIPASE 1 (GLIP1) depends on ET for gene expression and pathogen resistance. Here, promoter analysis of GLIP1 revealed ERELEE4 as the critical cis-element for ET-responsive GLIP1 expression. In a yeast one-hybrid screening, ORA59 was isolated as a specific transcription factor that binds to the ERELEE4 element, in addition to the well-characterized GCC box. We found that ORA59 regulates JA/ET-responsive genes through direct binding to these elements in gene promoters. Notably, ORA59 exhibited a differential preference for GCC box and ERELEE4, depending on whether ORA59 activation is achieved by JA and ET, respectively. JA and ET induced ORA59 phosphorylation, which was required for both activity and specificity of ORA59. Furthermore, RNA-seq and virus-induced gene silencing analyses led to the identification of ORA59 target genes of distinct functional categories in JA and ET pathways. Our results provide insights into how ORA59 can generate specific patterns of gene expression dynamics through JA and ET hormone pathways.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Ciclopentanos/metabolismo , Etilenos/metabolismo , Oxilipinas/metabolismo , Imunidade Vegetal/genética , Fatores de Transcrição/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/metabolismo , DNA de Plantas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Background and Objectives: Sugammadex is widely used in anesthesia to reverse rocuronium-induced neuromuscular blockade (NMB). In patients with compromised kidney function, most drugs show alteration of their pharmacokinetic profile with reduced clearance. The purpose of this article is to examine the efficacy, pharmacokinetics, and safety of sugammadex in end-stage renal disease (ESRD) patients receiving general anesthesia, using a systematic review. Materials and Methods: The databases of PubMed, EMBASE, the Cochrane Library, Web of Science, Scopus, KoreaMed, and ClinicalTrials.gov were searched for studies comparing the efficacy or safety outcomes of sugammadex administration for the reversal of rocuronium-induced NMB, in ESRD patients (group R) or in those with normal renal function (group N) undergoing surgery under general anesthesia. Results: We identified nine studies with 655 patients-six prospective, case-control studies with 179 patients (89 and 90 in groups R and N) and three retrospective observational studies with 476 ESRD patients. In the six prospective studies, the times taken to reach a train-of-four ratio ≥0.9, 0.8, and 0.7 were significantly longer in group R than in group N (weighted mean difference [95% confidence interval] [min]: 1.14 [0.29 to 2.00], 0.9 [0.24 to 1.57], 0.89 [0.20 to 1.57], respectively). The total plasma clearance of sugammadex was significantly lower in group R than in group N. There was no significant difference in the incidence of NMB recurrence and prolonged time to recovery between the groups. In the three retrospective studies, the possibility of sugammadex-related adverse events appears to be insignificant. Conclusions: Sugammadex may effectively and safely reverse rocuronium-induced NMB in patients with ESRD, although the recovery to a TOF ratio of 0.9 may be prolonged compared to patients with normal renal function. Further studies are needed, considering the small number of studies included and the high heterogeneity of some of the results.
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Falência Renal Crônica , Bloqueio Neuromuscular , Fármacos Neuromusculares não Despolarizantes , gama-Ciclodextrinas , Androstanóis , Humanos , Falência Renal Crônica/cirurgia , Estudos Prospectivos , Estudos Retrospectivos , Rocurônio , Sugammadex/uso terapêutico , gama-Ciclodextrinas/efeitos adversosRESUMO
BACKGROUND: Hypoxia inhibits the uptake of glutamate (a major neurotransmitter in the brain closely related to cognitive function) into brain cells, and the initial response of cells to cortical hypoxia depends on glutamate. Previous studies have suggested that magnesium may have protective effects against hypoxic injuries. In particular, magnesium L-threonate (MgT) may increase magnesium ion concentrations in the brain better than MgSO4 and improve cognitive function. METHODS: We evaluated cell viability under hypoxic conditions in the MgT- and MgSO4-treated human SH-SY5Y neurons, in vivo behavior using the T-maze test following hypoxia in MgT-treated zebrafish, activity of brain mitochondrial dehydrogenase by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and protein expression of the excitatory amino acid transporter (EAAT) 4 glutamate transporter by western blotting. RESULTS: Among the groups treated with hypoxia, cell viability significantly increased when pre-treated with 1 or 10 mM MgT (p = 0.009 and 0.026, respectively). Despite hypoxic insult, MgT-treated zebrafish showed preferences for the red compartment (p = 0.025 for distance and p = 0.007 for frequency of entries), suggesting memory preservation. TTC staining showed reduced cerebral infarction and preserved absorbance in the MgT-treated zebrafish brain after hypoxia (p = 0.010 compared to the hypoxia group). In addition, western blot showed upregulation of EAAT4 protein in the MgT treated group. CONCLUSIONS: Pre-treatment with MgT attenuated cell death and cerebral infarction due to hypoxia and protected cognitive function in zebrafish. In addition, MgT appeared to modulate expression of the glutamate transporter, EAAT4.
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Encéfalo/efeitos dos fármacos , Butiratos/farmacologia , Hipóxia/fisiopatologia , Magnésio/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Ácido Glutâmico/metabolismo , Hipóxia/tratamento farmacológico , Magnésio/farmacologia , Memória/efeitos dos fármacos , Memória/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Peixe-Zebra/metabolismoRESUMO
Transparent conducting electrodes (TCEs) based on silver nanowire (AgNW) networks possess high conductance, transmittance, and mechanical flexibility. However, due to the relatively high diffuse reflection of incident light on AgNWs, they cannot be practically implemented in displays requiring low pattern visibility. One promising strategy for solving this problem is to place an optical stack with high refractive index underneath the AgNW layer. In this work, AgNW-RuO2 nanosheet hybrid TCEs with low diffuse reflections are fabricated using metallic RuO2 nanosheets as undercoats. As predicted by theoretical simulations, RuO2 nanosheets with high refractive indices reduce the diffuse reflections of AgNWs by almost 8%. Moreover, after the partial etching of AgNWs, the difference in the diffuse reflections of their etched and non-etched regions becomes equal to about 0.003, leading to the formation of an invisible pattern. The film consisting of micro-sized RuO2 nanosheets is not damaged during etching, but instead forms a current path between different AgNWs broken by cyclic bending, resulting in a tenfold decrease in the resistance of the AgNW TCE after 170 000 cycles. Further, RuO2 nanosheets suppress the diffusion of humid air from the outside, thus improving the environmental stability of the AgNW-RuO2 nanosheet hybrid TCEs.
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OBJECTIVES: To reveal the suitable surface condition of an implant abutment for fibroblast attachment, the correlation between the surface characteristics of various materials and the human gingival fibroblast (HGF-1) attachment to the surfaces were analyzed. METHODS: Six kinds of surfaces comprised of machined titanium alloy (SM), machined Co-Cr-Mo alloy (CCM), titanium nitride coated titanium alloy (TiN), anodized titanium alloy (AO), composite resin coating on titanium alloy (R) and zirconia (Zr) were used. The measured surface parameters were Sa, Sq, Sz, Sdr, Sdq, Sal, Str and water contact angle (WCA). The HGF-1 cell attachment was investigated and the correlations were analyzed using a multiple regression analysis. RESULTS: The HGF-1 cell attachment was greater in the SM, TiN and Zr groups than the other groups and smallest in the CCM group (p = 0.0096). From the multiple regression analysis, the HGF-1 cell attachment was significantly correlated with Sdr, Sdq and WCA. When the R group was excluded, only WCA showed significant correlation with the fibroblast attachment. CONCLUSIONS: Within the limitations of this study, the cell attachment of human gingival fibroblasts was correlated with WCA, developed interfacial area ratio and surface slope. When the surfaces with Sa values of â¼ 0.2 µm or less were concerned, only WCA showed a correlation in a third order manner.
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Dente Suporte , Implantes Dentários , Materiais Dentários/química , Fibroblastos/fisiologia , Gengiva/citologia , Ligas , Adesão Celular/fisiologia , Linhagem Celular , Ligas de Cromo/química , Materiais Revestidos Biocompatíveis/química , Resinas Compostas/química , Ligas Dentárias/química , Humanos , Imageamento Tridimensional/métodos , Propriedades de Superfície , Titânio/química , Molhabilidade , Zircônio/químicaRESUMO
The state-of-the-art all-solid-state batteries have emerged as an alternative to the traditional flammable lithium-ion batteries, offering higher energy density and safety. Nevertheless, insufficient intimate contact at electrode-electrolyte surface limits their stability and electrochemical performance, hindering the commercialization of all-solid-state batteries. Herein, we conduct a systematic investigation into the effects of shear force in the dry electrode process by comparing binder-free hand-mixed pellets, wet-processed electrodes, and dry-processed electrodes. Through digitally processed images, we quantify a critical factor, 'coverage', the percentage of electrolyte-covered surface area of the active materials. The coverage of dry electrodes was significantly higher (67.2%) than those of pellets (30.6%) and wet electrodes (33.3%), enabling superior rate capability and cyclability. A physics-based electrochemical model highlights the effects of solid diffusion by elucidating the impact of coverage on active material utilization under various current densities. These results underscore the pivotal role of the electrode fabrication process, with the focus on the critical factor of coverage.
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Thin films of Indium tin oxide (ITO), Gallium zinc oxide (GZO), and Indium zinc tin oxide (IZTO) were deposited on glass substrates by pulsed direct current magnetron sputtering at room temperature. The structural, optical, and electrical properties of the films were investigated towards evaluating their applications as flexible anodes. IZTO films exhibited the lowest resistivity (6.3 x 10(-4) Omega cm). Organic light-emitting diodes (OLEDs) were fabricated using the ITO, GZO, and IZTO films as anode layers. The turn-on voltages at a current density of 4.5 mA/cm2, 5.5 mA/cm2, 6.5 mA/cm2 were 5.5 V, 13.7 V, and 4.7 V for the devices with ITO, GZO, and IZTO anodes, respectively. The best performance was observed with the IZTO film, indicating its suitability as an alternative material for conventional ITO anodes used in OLEDs and flexible displays.
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Here we tried to show the possibility of mechanical milling method for fabrication of SiC nanoparticles and ink-jet printing method to make SiC patterns for use as several applications, e.g., micro hotplates. Planetary milling was employed to fabricate the nano-scale SiC particles from coarse powders. After 100 hours of milling, the size of the SiC particles decreased to about 100 nm, which was sufficient for the formulation of ink for ink-jet printing. The SiC particles were dispersed in an ink system consisted of ethylene glycol and ethanol with a small amount of additives. The ink with SiC nanoparticles could be successfully printed on an alumina substrate by the ink-jet printing method.
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BACKGROUND: Abnormalities of bone metabolism may be involved in the pathogenesis of ossification of the posterior longitudinal ligament (OPLL) of the spine. Besides its hemostatic effect, vitamin K epoxide reductase complex subunit 1 (VKORC1) plays a pivotal role in bone mineralization. The aim of this study is to investigate whether single nucleotide polymorphisms (SNPs) of the VKORC1 gene are associated with the occurrence of OPLL in a Korean population. METHOD: A total of 98 patients with OPLL and 200 controls were genotyped for the VKORC1-1639G>A SNP (rs9923231) by polymerase chain reaction and restriction fragment length polymorphism analysis. All the patients (n = 98) in this study underwent surgery (60, posterior-only approach; 36, anterior-only approach; 2, combined anterior and posterior approach) during their admission. We analyzed this association separately according to the gender and OPLL subgroup: OPLL continuous group (continuous type plus mixed type) and OPLL segmental group (segmental and localized type). RESULTS: We found that the genotype VKORC1-1639G>A frequency was significantly associated with the occurrence of the OPLL in the female group (adjusted odds ratio = 5.22, 95 % confidence interval: 1.675 to 16.269, p = 0.004). However, there was no overall association between the OPLL susceptibility and VKORC1-1639G>A polymorphism. A subgroup analysis did not show any significant correlation between VKORC1-1639G>A polymorphism and subgroup of OPLL either. CONCLUSION: Our results suggest that the VKORC1-1639G>A SNP may increase susceptibility to OPLL in women. However, there was only a statistical association in the female group despite a number of stratified analyses. Therefore, the findings should be interpreted with caution, and further genetic study is needed to improve our understanding of the role of VKORC1 polymorphisms in determining the risk of OPLL occurrence.
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Predisposição Genética para Doença , Ossificação do Ligamento Longitudinal Posterior/genética , Polimorfismo de Nucleotídeo Único/genética , Vitamina K Epóxido Redutases/genética , Adulto , Idoso , Povo Asiático/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Ossificação do Ligamento Longitudinal Posterior/etiologia , Fatores SexuaisRESUMO
INTRODUCTION: It is increasingly recognized that regular boosters will be necessary for the continued management of the COVID-19 pandemic. While vaccine hesitancy in the context of the initial COVID-19 vaccinations has been extensively studied, less is known about hesitancy around boosters in the post-pandemic era, where the immediate threat of COVID-19 has diminished. METHODS: Using 5,584 survey responses from people who had received at least one COVID-19 vaccine dose based on a four-round survey between May and November 2022, we examined various factors that affect booster vaccine uptake and the willingness to take an additional shot. Ordinary least squares regressions were conducted to confirm the statistical significance of the findings. RESULTS: Nearly 99% of vaccinated respondents reported having had two COVID-19 vaccine doses, while 69% of respondents reported having received a booster shot (three or more vaccine doses) and 48% reported being willing to get another shot. Booster uptake was strongly increased along with the degree of trust in the Korean Disease Control Agency (KDCA) and was also significantly associated with older age, gender, political propensity, and household income-level. When examining willingness to get an additional shot, the predictors were similar to booster vaccine uptake. However, the effect of trust in the KDCA became more salient. CONCLUSION: The factors associated with booster uptake and willingness to continue to boost are similar to those associated with initial vaccine acceptance in the ROK, namely trust in the public health authority and older age. Despite high initial uptake in the ROK, convincing the public of the continued necessity of routine immunization against COVID-19 may pose challenges in the post-pandemic era.
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COVID-19 , Confiança , Humanos , Vacinas contra COVID-19 , Pandemias/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , Saúde Pública , Vacinação , República da Coreia/epidemiologiaRESUMO
Introduction: As South Korea is fast becoming an aging society, the need for integrated care of the elderly has increased. 'Community Integrated Care Initiatives' have been implemented by the Ministry of Health and Welfare. However, home healthcare is insufficient to meet this need. Description: The National Health Insurance Service (NHIS) launched the initiative, 'Patient-Centered Integrated model of Home Health Care Services in South Korea (PICS-K)'. Its purpose is to coordinate home healthcare providers by establishing a home health care support center (HHSC) in public hospitals starting in 2021. The PICS-K has six main features: integration of primary care-hospital-personal care-social services through a consortium, HHSC in hospitals with primary care collaboration, increased accessibility, interdisciplinary team (IDT), patient-centeredness, and education. Discussion: Integrating healthcare, personal care, and social services at multiple levels is necessary. Accordingly, platforms to share participant information and service records, and institutional payment system reforms are required. Conclusion: In public hospitals, the HHSC supported primary care, which provides home healthcare. The model combined community healthcare and social services to accomplish the aging-in-place of the homebound population by focusing on their needs. This model will be applicable to other regions in Korea.
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Electrical stimulation such as transcranial direct current stimulation (tDCS) is widely used to treat neuropsychiatric diseases and neurological disorders. Computational modeling is an important approach to understand the mechanisms underlying tDCS and optimize treatment planning. When applying computational modeling to treatment planning, uncertainties exist due to insufficient conductivity information inside the brain. In this feasibility study, we performed in vivo MR-based conductivity tensor imaging (CTI) experiments on the entire brain to precisely estimate the tissue response to the electrical stimulation. A recent CTI method was applied to obtain low-frequency conductivity tensor images. Subject-specific three-dimensional finite element models (FEMs) of the head were implemented by segmenting anatomical MR images and integrating a conductivity tensor distribution. The electric field and current density of brain tissues following electrical stimulation were calculated using a conductivity tensor-based model and compared to results using an isotropic conductivity model from literature values. The current density by the conductivity tensor was different from the isotropic conductivity model, with an average relative difference |rD| of 52 to 73%, respectively, across two normal volunteers. When applied to two tDCS electrode montages of C3-FP2 and F4-F3, the current density showed a focused distribution with high signal intensity which is consistent with the current flowing from the anode to the cathode electrodes through the white matter. The gray matter tended to carry larger amounts of current densities regardless of directional information. We suggest this CTI-based subject-specific model can provide detailed information on tissue responses for personalized tDCS treatment planning.
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This paper suggests a force sensor array measuring contact force based on intensity change of light transmitted throughout optical waveguide. For transparency and flexibility of the sensor, two soft prepolymers with different refractive index have been developed. The optical waveguide consists of two cladding layers and a core layer. The top cladding layer is designed to allow light scattering at the specific area in response to finger contact. The force sensor shows a distinct tendency that output intensity decreases with input force and measurement range is from 0 to -13.2 dB.
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Polímeros/química , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Transdutores de Pressão , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Estresse MecânicoRESUMO
Vitamin D(3) upregulated protein 1 (VDUP1) is a candidate tumor suppressor, the expression of which is dramatically reduced in various tumor tissues. In this study, we found that VDUP1 expression is suppressed during human hepatic carcinogenesis, and mice lacking VDUP1 are much more susceptible to diethylnitrosamine-induced hepatocarcinogenesis compared with wild type mice. VDUP1-deficient tumors proliferated significantly more than wild type tumors and had corresponding changes in the expression of key cell cycle regulatory proteins. In addition, the hepatomitogen-induced response was associated with a considerable increase in the release of TNF-α and subsequent enhancement of NF-κB activation in VDUP1-deficient mice. When cells were treated with TNF-α, the VDUP1 level was markedly reduced, concomitant with elevated NF-κB activation. Furthermore, the overexpression of VDUP1 resulted in the robust suppression of TNF-α-activated NF-κB activity via association with HDAC1 and HDAC3. These results indicate that VDUP1 negatively regulates hepatocarcinogenesis by suppressing TNF-α-induced NF-κB activation.
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Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/metabolismo , Neoplasias Hepáticas/metabolismo , NF-kappa B/metabolismo , Tiorredoxinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática/fisiologia , Humanos , Imuno-Histoquímica , Imunoprecipitação , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Knockout , Microscopia de Fluorescência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologiaRESUMO
D-(pi-A)n type dyes of triphenylamine derivatives were synthesized and their absorption and luminescence in different solvents were examined to investigate solvent dependent properties observed for their emissions in solvents with different dielectric constants. The emission wavelengths showed a dramatic blue shift with increasing solvent polarity. The results of molecular orbital calculations by computer simulation, based on Material Studio suite of programs, were found to reasonably account for the spectral properties. Relative levels of HOMO and LUMO were measured and calculated and all derivatives exhibited strong solid fluorescence with distinctively different FWHMs.
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Ionizing radiation delivers sufficient energy inside the human body to create ions, which kills cancerous tissues either by damaging the DNA directly or by creating charged particles that can damage the DNA. Recent magnetic resonance (MR)-based conductivity imaging shows higher sensitivity than other MR techniques for evaluating the responses of normal tissues immediately after irradiation. However, it is still necessary to verify the responses of cancer tissues to irradiation by conductivity imaging for it to become a reliable tool in evaluating therapeutic effects in clinical practice. In this study, we applied MR-based conductivity imaging to mouse brain tumors to evaluate the responses in irradiated and non-irradiated tissues during the peri-irradiation period. Absolute conductivities of brain tissues were measured to quantify the irradiation effects, and the percentage changes were determined to estimate the degree of response. The conductivity of brain tissues with irradiation was higher than that without irradiation for all tissue types. The percentage changes of tumor tissues with irradiation were clearly different than those without irradiation. The measured conductivity and percentage changes between tumor rims and cores to irradiation were clearly distinguished. The contrast of the conductivity images following irradiation may reflect the response to the changes in cellularity and the amounts of electrolytes in tumor tissues.
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In this study, ultrafine nickel oxide nanoparticles (NiO NPs) were well synthesized using a simple wet chemical method under low temperature, 300 °C. An Ni(OH)2 precursor was well precipitated by dropping NH4OH into an Ni(Ac)2 solution. TG-DTA showed that the weight of the precipitate decreases until 300 °C; therefore, the precursor was heat-treated at 300 °C. X-ray diffraction (XRD) patterns indicated that hexagonal-structured NiO NPs with (200) preferred orientation was synthesized. In addition, BET specific surface area (SSA) and HRTEM analyses revealed that spherical NiO NPs were formed with SSA and particle size of 60.14 m2/g and ca. 5-15 nm by using the low temperature method. FT-IR spectra of the NiO NPs showed only a sharp vibrating absorption peak at around 550 cm-1 owing to the Ni-O bond. Additionally, in UV-vis absorption spectra, the wavelength for absorption edge and energy band gap of the ultrafine NiO NPs was 290 nm and 3.44 eV.
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PURPOSE: Periodontal treatment aims at complete regeneration of the periodontium, and developing strategies for periodontal regeneration requires a deep understanding of the tissues composing the periodontium. In the present study, the stemness characteristics and gene expression profiles of cementum-derived cells (CDCs) were investigated and compared with previously established human stem cells. Candidate marker proteins for CDCs were also explored. METHODS: Periodontal ligament stem cells (PDLSCs), pulp stem cells (PULPSCs), and CDCs were isolated and cultured from extracted human mandibular third molars. Human bone marrow stem cells (BMSCs) were used as a positive control. To identify the stemness of CDCs, cell differentiation (osteogenic, adipogenic, and chondrogenic) and surface antigens were evaluated through flow cytometry. The expression of cementum protein 1 (CEMP1) and cementum attachment protein (CAP) was investigated to explore marker proteins for CDCs through reverse-transcription polymerase chain reaction. To compare the gene expression profiles of the 4 cell types, mRNA and miRNA microarray analysis of 10 samples of BMSCs (n=1), PDLSCs (n=3), PULPSCs (n=3), and CDCs (n=3) were performed. RESULTS: The expression of mesenchymal stem cell markers with a concomitant absence of hematopoietic markers was observed in PDLSCs, PULPSCs, CDCs and BMSCs. All 4 cell populations also showed differentiation into osteogenic, adipogenic, and chondrogenic lineages. CEMP1 was strongly expressed in CDCs, while it was weakly detected in the other 3 cell populations. Meanwhile, CAP was not found in any of the 4 cell populations. The mRNA and miRNA microarray analysis showed that 14 mRNA genes and 4 miRNA genes were differentially expressed in CDCs vs. PDLSCs and PULPSCs. CONCLUSIONS: Within the limitations of the study, CDCs seem to have stemness and preferentially express CEMP1. Moreover, there were several up- or down-regulated genes in CDCs vs. PDLSCs, PULPSCs, and BMSCs and these genes could be candidate marker proteins of CDCs.
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We have designed and synthesized a triphenylamine-based new dye sensor and corresponding selective and sensitive detection functions for heavy metal ions were investigated. The complex potentials for heavy metal ions were characterized by the measurements of optical properties using UV-Vis spectrophotometer and spectrofluorophotometer. Furthermore, the molecular energy levels of the designed dye sensors were also computationally optimized and calculated by the density function theory (DFT) with exchange correction functional of local density approximation (LDA) based on the Perdew-Wang (PWC) set and cyclic voltammetry.
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Compostos de Anilina/síntese química , Corantes/síntese química , Compostos de Anilina/química , Corantes/química , Espectrometria de Fluorescência , Espectrofotometria UltravioletaRESUMO
The multi-layer dye film as an acid-alkali reversible sensing material has been fabricated using poly(diallyldimethylammonium chloride) (PDDAC) and 1,3-bisdicyanovinylindane dye compound by electrostatic forces and layer-by-layer self-assembly attractions. These dye layers show reversible color switchable properties. The dye shows blue colored characteristic in alkaline condition. However, when strong acidic atmospheres are subjected to colored dye structure, it converts to the colorless form of the dye structure within the multi film layers. These results were characterized using absorbance measurement and Atomic Force Microscopy (AFM). UV-vis absorption spectra of the multi-layer films increased linearly at 583 nm, which indicated that fabrication of the dye layer as a sensing moiety proceeded regularly. The dye fabrication films also clearly showed the hydrochloric gas sensing properties with reversible color changes.