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Glycyrrhetinic acid (GA) is a saponin compound, isolated from licorice (Glycyrrhiza glabra), which has been wildly explored for its intriguing pharmacological and medicinal effects. GA is a triterpenoid glycoside displaying an array of pharmacological and biological activities, including anti-inflammatory, anti-bacterial, antiviral and antioxidative properties. In this study, we investigated the underlying mechanisms of GA on acne vulgaris through network pharmacology and proteomics. After the intersection of the 154 drug targets and 581 disease targets, 37 therapeutic targets for GA against acne were obtained. A protein-protein interaction (PPI) network analysis highlighted TNF, IL1B, IL6, ESR1, PPARG, NFKB1, STAT3 and TLR4 as key targets of GA against acne, which is further verified by molecular docking. The experimental results showed that GA inhibited lipid synthesis in vitro and in vivo, improved the histopathological damage of skin, prevented mast cell infiltration and decreased the level of pro-inflammatory cytokines, including TNF-α, IL-1ß and IL-6. This study indicates that GA may regulate multiple pathways to improve acne symptoms, and the beneficial effects of GA against acne vulgaris might be through the regulation of sebogenesis and inflammatory responses.
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Acné Vulgar , Ácido Glicirretínico , Simulación del Acoplamiento Molecular , Farmacología en Red , Acné Vulgar/tratamiento farmacológico , Acné Vulgar/patología , Ácido Glicirretínico/farmacología , Ácido Glicirretínico/química , Animales , Humanos , Ratones , Mapas de Interacción de Proteínas/efectos de los fármacos , Citocinas/metabolismo , Antiinflamatorios/farmacología , Antiinflamatorios/química , Proteómica/métodos , Modelos Animales de EnfermedadRESUMEN
Mining entity and relation from unstructured text is important for knowledge graph construction and expansion. Recent approaches have achieved promising performance while still suffering from inherent limitations, such as the computation efficiency and redundancy of relation prediction. In this paper, we propose a novel hybrid attention and dilated convolution network (HADNet), an end-to-end solution for entity and relation extraction and mining. HADNet designs a novel encoder architecture integrated with an attention mechanism, dilated convolutions, and gated unit to further improve computation efficiency, which achieves an effective global receptive field while considering local context. For the decoder, we decompose the task into three phases, relation prediction, entity recognition and relation determination. We evaluate our proposed model using two public real-world datasets that the experimental results demonstrate the effectiveness of the proposed model.
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In this paper, a robust observer-based sliding mode control algorithm is proposed to address the modelling and measurement inaccuracies, load variations, and external disturbances of flexible articulated manipulators. Firstly, a sliding mode observer was designed with exponential convergence to observe system state accurately and to overcome the measuring difficulty of the state variables, unmeasurable quantities, and external disturbances. Next, a robust sliding mode controller was developed based on the observer, such that the output error of the system converges to zero in finite time. In this way, the whole system achieves asymptotic stability. Finally, the convergence conditions of the observer were theoretically analyzed to verify the convergence of the proposed algorithm, and simulation was carried out to confirm the effectiveness of the proposed method.
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Algoritmos , Simulación por ComputadorRESUMEN
BACKGROUND: Veratrum nigrum (Liliaceae) is perennial medicinal plant widely used to treat various conditions. To determine its insecticidal properties against the German cockroach (Blattella germanica), several laboratory tests were carried out. METHODS: A 4kg dry sample of V. nigrum root was purchased from the medicinal material market in Yunnan Province in 2015, China. In contact toxicity tests, V. nigrum alkaloidal extract was topically applied to the abdomen of cockroaches using a micro-applicator. In vitro acetylcholinesterase (AChE) activity tests were performed using a modified Ellman method. RESULTS: Veratrum nigrum alkaloidal extract was toxic to male adults and 4th nymphs cockroaches, with median lethal dose (LD50) values of 14.90µg/insect, 14.21µg/insect for adults and 41.45µg/insect, 39.01µg/insect for 4th nymphs after 24h and 48h exposure, respectively. There was a significant difference between adults and nymphs in terms of tolerance to V. nigrum alkaloidal extract. There was no significant difference in mortalities at 24h and 48h, the lethal effect of V. nigrum alkaloidal extract on German cockroach was quick. AChE activity tests showed that V. nigrum alkaloidal extract had an excellent inhibitory effect on AChE: inhibition in the 4th nymphs and male adults had 50% inhibiting concentration (IC50) values of 3.56mg/ml and 5.78mg/ml respectively. The inhibitory effect of AChE activity was positively correlated with inhibitory time (0-20min), at a concentration of 1mg/ml, inhibition of nymph and adult AChE activity had 50% inhibiting time (IT50) values of 8.34min and 16.75min, respectively. CONCLUSION: V. nigrum may be explored as a potential natural insecticide for control of the German cockroach.
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Due to the importance of pancreatic cholesterol esterase (CEase) as a potential target in atherosclerosis and for the development of hypocholesterolemic agents, there are increasing interests in designing and synthesizing CEase inhibitors. In the present study, we prepared forty-five isocoumarin phosphorus analogues (i.e., phosphaisocoumarins) and investigated the inhibition of these compounds on the CEase. The results showed that some phosphaisocoumarins could act as potent inhibitors of CEase. The most potent inhibitors, compounds 9d, 10a and 12e give IC50 values of 4.8 microM, 2.3 microM and 1.9 microM, respectively. The inhibition mechanism and kinetic characterization studies indicate that they are reversible competitive inhibitors.
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Inhibidores Enzimáticos/farmacología , Isocumarinas/farmacología , Páncreas/enzimología , Esterol Esterasa/antagonistas & inhibidores , Animales , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Isocumarinas/síntesis química , Isocumarinas/química , Cinética , Estructura Molecular , Estereoisomerismo , Esterol Esterasa/metabolismo , Relación Estructura-Actividad , PorcinosRESUMEN
We find the explicit state vector for Torres-Vega-Frederick phase space representation [Go. Torres-Vega and J. H. Frederick, J. Chem. Phys. 98, 3103 (1993)], denoted by Gamma. This set of states make up a complete and nonorthogonal representation. The Weyl ordered form of Gamma Gamma [see text for the sign] is derived, which can clearly exhibit the statistical behavior of marginal distribution of Gamma Gamma [see text for the sign]. The minimum uncertainty relation for mid R:Gamma is demonstrated, which shows it being a coherent squeezed state.
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The Einstein-Podolsky-Rosen entangled state representation is applied to studying the admissibility condition of mother wavelets for complex wavelet transforms, which leads to a family of new mother wavelets. Mother wavelets thus are classified as the Hermite-Gaussian type for real wavelet transforms and the Laguerre-Gaussian type for the complex case.
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Usually a wavelet transform is based on dilated-translated wavelets. We propose a symplectic-transformed-translated wavelet family psi(*)(r,s)(z-kappa) (r,s are the symplectic transform parameters, |s|(2)-|r|(2)=1, kappa is a translation parameter) generated from the mother wavelet psi and the corresponding wavelet transformation W(psi)f(r,s;kappa)=integral(infinity)(-infinity)(d(2)z/pi)f(z)psi(*)(r,s)(z-kappa). This new transform possesses well-behaved properties and is related to the optical Fresnel transform in quantum mechanical version.
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We find that the Collins diffraction formula in cylindrical coordinates is just the transformation matrix element of a three-parameter two-mode squeezing operator in the deduced entangled state representation. This is a new tie connecting the unitary transform in quantum optics to the generalized Hankel transform in Fourier optics. The group multiplication rule of the squeezing operators maps to the Collins formula related to two successive Hankel transforms.
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The admissibility condition of a mother wavelet is explored in the context of quantum optics theory. By virtue of Dirac's representation theory and the coherent state property we derive a general formula for finding qualified mother wavelets. A comparison between a wavelet transform computed with the newly found mother wavelet and one computed with a Mexican hat wavelet is presented.
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A gas-sensor utilizing cataluminescence (CTL) on nanosized gamma-Al2O3 + Nd2O3 for measuring low concentrations of gaseous ethylene dichloride (EDC) was developed. The results showed that gamma-Al2O3 nanoparticles as a catalyst offered high sensitivity and selectivity in the detection of EDC. The addition of a small quantity of Nd2O3 increased the intensity of CTL more than two-fold. Quantitative analysis was performed at a wavelength of 400 nm and at an optimal temperature of 279 degrees C, and the optimal flow rate of carrier gas was 320 mL/min. Under the optimized conditions, the linear range of CTL intensity vs. concentration is 6-5000 ppm (R = 0.9996; n = 7), with a detection limit of 2 ppm. The response time is <5 s. No interference or only very low levels of significant interference were observed when substances such as formaldehyde, n-hexane, methyl benzene, carbon tetrachloride, chloroform and benzene were passed through the sensor.
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Contaminantes Atmosféricos/análisis , Dicloruros de Etileno/análisis , Mediciones Luminiscentes/métodos , Óxido de Aluminio , Calibración , Mediciones Luminiscentes/normas , Nanoestructuras , Neodimio , ÓxidosRESUMEN
Using the entangled-state method in quantum mechanics, we find that the eigenmodes of the fractional Hankel transform are two-variable Hermite-Gaussian functions that can be rewritten in a clearer form as Laguerre polynominals.