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1.
J Chromatogr Sci ; 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37647634

RESUMEN

Pinus massoniana needles, a traditional herb, were applied to prevent hair loss in China. Studies available mainly focused on pine needle flavonoids with various biological activities. However, there has been no pharmacokinetics study of the flavonoids from Pinus needles extract. A selective and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to simultaneously quantify taxifolin, quercetin and catechin in rat plasma. To separate the three constituents, an Agilent Extend-C18 column (2.1 mm × 100 mm, 1.8 µm) was used with a mobile phrase of (A) 0.1% formic acid and (B) acetonitrile. The analytes were measured by multiple reaction monitoring in the negative ionization mode. There was good linearity in the established UHPLC-MS/MS method, with a coefficient of determination (r2) of >0.99. The accuracy, intra-day and inter-day precision and recovery were all satisfactory and these 3 compounds were stable under the tested conditions. The validated method in this study was successfully applied to pharmacokinetic study in healthy rats after oral and transdermal administration of Pinus needles extract. The results could provide further research foundation for pine needle extract as external preparations.

2.
Basic Clin Pharmacol Toxicol ; 131(6): 474-486, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36126111

RESUMEN

Elevated levels of circulating fibroblast growth factor 21 (FGF21) have been reported in patients with hyperuricemia. However, the effect of FGF21 in hyperuricemic nephropathy (HN) remains unexplored. Here, we investigated the effect and mechanism of action of FGF21 on HN. HN model was induced with adenine and potassium oxysalt in wild-type C57BL/6 mice and FGF21-/- mice. For in vitro studies, human renal tubular epithelial (HK-2) cells were exposed to uric acid with/without FGF21 or ß-Klotho-siRNA. Here, we reported aggravated renal dysfunction and structural damage in the FGF21-/- mice compared to the wild-type mice. These were evident in the upsurge of inflammatory factors IL-1ß, TNF-α, IL-6, and IL-18; fibrotic markers Collagen I and α-SMA; and oxidation products ROS and MDA. However, exogenous administration of FGF21 to wild-type HN mice significantly reversed these negative effects. In terms of mechanism, FGF21 significantly inhibited NF-κB/NLRP3 and TGF-ß1/Smad3 pathways and promoted nuclear translocation of Nrf2 both in vivo and in vitro. Furthermore, the silencing of ß-Klotho was marked by the attenuation of the improved effect of FGF21 on cell damage. In conclusion, our studies revealed that exogenous FGF21 treatment significantly improved HN, which was achieved by the inhibition of inflammation, fibrosis, and oxidative stress.


Asunto(s)
Hiperuricemia , Humanos , Ratones , Animales , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/metabolismo , Ácido Úrico , Transducción de Señal , Ratones Endogámicos C57BL , Fibrosis , Estrés Oxidativo , Inflamación/tratamiento farmacológico
3.
IEEE Trans Pattern Anal Mach Intell ; 44(8): 4321-4338, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33621168

RESUMEN

Existing face hallucination methods based on convolutional neural networks (CNNs) have achieved impressive performance on low-resolution (LR) faces in a normal illumination condition. However, their performance degrades dramatically when LR faces are captured in non-uniform illumination conditions. This paper proposes a Recursive Copy and Paste Generative Adversarial Network (Re-CPGAN) to recover authentic high-resolution (HR) face images while compensating for non-uniform illumination. To this end, we develop two key components in our Re-CPGAN: internal and recursive external Copy and Paste networks (CPnets). Our internal CPnet exploits facial self-similarity information residing in the input image to enhance facial details; while our recursive external CPnet leverages an external guided face for illumination compensation. Specifically, our recursive external CPnet stacks multiple external Copy and Paste (EX-CP) units in a compact model to learn normal illumination and enhance facial details recursively. By doing so, our method offsets illumination and upsamples facial details progressively in a coarse-to-fine fashion, thus alleviating the ambiguity of correspondences between LR inputs and external guided inputs. Furthermore, a new illumination compensation loss is developed to capture illumination from the external guided face image effectively. Extensive experiments demonstrate that our method achieves authentic HR face images in a uniform illumination condition with a 16× magnification factor and outperforms state-of-the-art methods qualitatively and quantitatively.


Asunto(s)
Algoritmos , Cara , Alucinaciones , Humanos , Redes Neurales de la Computación
4.
Bioresour Technol ; 326: 124768, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33529982

RESUMEN

Corncob is an abundant and renewable resource that could be enzymatically hydrolyzed to fermentable sugar. A major impediment in corncob utilization is the low hydrolysis efficiency at high-solids content. This study attempted different pretreatment methods and fed-batch modes to achieve a 25% solids content hydrolysis with high yields. Natural corncobs were compared with acid-treated and acid-alkali-treated corncobs in terms of kinetics parameters, conversion rate and glucose titer. By feeding in batches, a "low amount and high frequency" mode (10%-3%-3%-3%-3%-3%, every 5 h) was confirmed to be optimal for a 25% high-solids hydrolysis system with a cellulase loading of 12 mg/g (7.3 FPU/g), resulted with an 84.4% glucose yield at 96 h. Our results demonstrated that combination of both optimized pretreatment method and fed-batch mode were a favored process model for high-solids hydrolysis of lignocellulose, boosting cellulose hydrolysis efficiency and sugar yields on an industrial scale.


Asunto(s)
Celulasa , Zea mays , Álcalis , Celulosa , Hidrólisis
5.
Int Immunopharmacol ; 85: 106644, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32474387

RESUMEN

Systemic sclerosis (SSc) is induced by variety of factors and eventually causes multiple organ damage. In recent years, biological agents targeting cytokines and cell surface molecules have gradually come to market. Here, the anti-inflammatory and antifibrotic effects of a novel bispecific antibody (FL-BsAb1/17) targeting interleukin-17A (IL-17A) and interleukin-1ß (IL-1ß) were detected. Bleomycin (BLM) was subcutaneously injected for 21 consecutive days to establish the SSc mouse model, and mice were subsequently treated with etanercept or different doses (1, 5, 10 mg/kg) of FL-BsAb1/17. The results showed that FL-BsAb1/17 treatment (10 mg/kg, 5 mg/kg) significantly attenuated BLM-induced SSc-like inflammation by inhibiting the expression of inflammatory factors (IL-17A, IL-1ß, IL-8, IL-22, IL-23, IL-6) and fibrosis, with specific outcomes of dermis thickening and lung fibrosis, by inhibiting the expression of fibrotic factors (TGF-ß, α-sma, Col-1, Col-3) in the serum, skin and lungs. In addition, FL-BsAb1/17 (10 mg/kg, 5 mg/kg) downregulated protein levels of TGF-ß and phosphorylated Smad2/3 in the skin and lungs and reduced collagen 1 protein levels. This indicated that FL-BsAb1/17 can inhibit the development of fibrosis by inhibiting the TGF-ß/Smad2/3 signaling pathway. FL-BsAb1/17 (10 mg/kg, 5 mg/kg) could also effectively reduce the content of MDA, increase the activity of SOD and CAT, and improve the total antioxidant capacity (T-AOC). In conclusion, FL-BsAb1/17 alleviated BLM-induced SSc by downregulating inflammatory cascades, relieving oxidative stress and inhibiting TGF-ß/Smad2/3 signaling. These data suggest that FL-BsAb1/17 has potential as a novel therapeutic candidate for SSc.


Asunto(s)
Anticuerpos Biespecíficos/uso terapéutico , Esclerodermia Sistémica/tratamiento farmacológico , Animales , Bleomicina , Citocinas/inmunología , Modelos Animales de Enfermedad , Femenino , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Ratones Endogámicos BALB C , Estrés Oxidativo/efectos de los fármacos , Esclerodermia Sistémica/inducido químicamente , Esclerodermia Sistémica/inmunología , Esclerodermia Sistémica/patología , Piel/efectos de los fármacos , Piel/inmunología , Piel/patología
6.
Food Sci Nutr ; 7(6): 1997-2005, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31289647

RESUMEN

Many Lactobacillus plantarum strains can secrete some antimicrobial substances and be added to food as antimicrobial agents and preservatives. In this study, three L. plantarum strains (P1, S11, and M7) with strong antimicrobial activity against three pathogenic bacteria were isolated from Xinjiang traditional dairy products. Five common organic acids produced by fermentation of strains play a key role in inhibiting three pathogenic bacteria. At the same pH, the antimicrobial activity of the fermentation broth against Escherichia coli and Salmonella is stronger than that of the organic acid alone. Thus, three kinds of antimicrobial agents (P1-1, M7-1, and S11-1) mixed with five common organic acids were produced. Moreover, the antimicrobial activity against Salmonella ASI.1174 of the antimicrobial agents was about 30% higher than that of the fermentation broth. In addition, organic acid antimicrobial agents combined in different proportions can inhibit different pathogenic bacteria. According to this result, it is a potential approach to develop novel antimicrobial agents used in food preservation by mixing different organic acids.

7.
Artículo en Inglés | MEDLINE | ID: mdl-30575535

RESUMEN

In this paper, we present a novel high-frequency facial feature and a high-frequency based sparse representation classification to tackle single sample face recognition (SSFR) under varying illumination. Firstly, we propose the assumption that QRCP bases can represent intrinsic face surface features with different frequencies, and their corresponding energy coefficients describe illumination intensities. Based on this assumption, we take QRCP bases with corresponding weighting coefficients (i.e. the major components of energy coefficients) to develop the high-frequency facial feature of the face image, which is named as QRCP-face. The normalized QRCP-face (NQRCPface) is constructed to further constraint illumination effects by normalizing the weighting coefficients of QRCP-face. Moreover, we propose the adaptive QRCP-face (AQRCP-face) that assigns a special parameter to NQRCP-face via the illumination level estimated by the weighting coefficients. Secondly, we consider that the differences of pixel images cannot model the intraclass variations of generic faces with illumination variations, and the specific identification information of the generic face is redundant for the current SSFR with generic learning. To tackle above two issues, we develop a general high-frequency based sparse representation (GHSP) model. Two practical approaches separated high-frequency based sparse representation (SHSP) and unified high-frequency based sparse representation (UHSP) are developed. Finally, the performances of the proposed methods are verified on the Extended Yale B, CMU PIE, AR, LFW and our self-built Driver face databases. The experimental results indicate that the proposed methods outperform previous approaches for SSFR under varying illumination.

8.
Huan Jing Ke Xue ; 34(9): 3654-62, 2013 Sep.
Artículo en Chino | MEDLINE | ID: mdl-24289019

RESUMEN

The distributions, soil environment status and potential ecological risk of heavy metals were studied in beach soil of returning the cropland into Yellow River beach region in Kaifeng by the Nemerows and Håkansons methods. The results showed that (1) as Among the average contents of the five heavy metals Pb, Cr, Hg, As and Cd, the highest was the average content of Cr, and the lowest was the average content of Pb and Hg. In addition to Hg, the coefficients of variation of other heavy metals were relatively small, indicating that the content of heavy metals was quite different at different sites, and to some extent, relecting that Hg, As and Pb were the major elements polluting the soil, among which, Pb pollution was the pollution with universality. There was little difference in the contents of Cr and Cd from village to village the coefficient of variation was small, and the contents were below the national standard level. (2) There was significant difference in the spatial distribution of soil heavy metal elements in the upper, the middle and lower sections of the study area. The upper section was clean, the middle section was slightly polluted, and the lower section was enriched with pollutants. (3) The distribution of heavy metals in the beach region inside and outside the levees of Yellow River was closely related to the distribution of the residential regions. In the upper section of the beach region (southwest), the population was large and the contents of heavy metals were high. The contents of heavy metals were lower in the near river zone than outside the levees of Yellow River. And the heavy metal contents in the middle and lower section were higher than those outside the levees of Yellow River, while the lower section (northwest) showed a tendency of pollution enrichment. (4) In the view of the average individual potential ecological risk index of heavy metals (E(r)i), the potential ecological risk of Hg reached intense levels, and the potential ecological risk of Pb's contribution to the integrated risk was 50.5%, which was the heavy metal with highest ecological risks. Cd and Pb had a moderate ecological risk, while As and Cr had minor ecological risk. Ecological hazards of heavy metals ranked in the ascending order of Hg > Pb > As > Cd > Cr. (5) The ecological hazard of the heavy metals was ranked in the order Hg > Cd > As > Pb > Cr. Based on the potential ecological risk level corresponding to the RI values, it was shown that there was moderate potential ecological risks of heavy metals in the Yellow River beach region in Kaifeng.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes del Suelo/análisis , China , Ciudades , Medición de Riesgo , Ríos , Suelo/química
9.
IEEE Trans Biomed Circuits Syst ; 7(6): 841-50, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24473548

RESUMEN

A 0.16 nJ/b MICS transmitter and 0.18 nJ/b super-regenerative receiver are demonstrated, where each is specifically designed to operate in the near-threshold region. The low-VDD transmitter utilizes a sub-harmonic injection-locked ring oscillator, edge combiner for frequency multiplication, and class-C power amplifier. The low-VDD receiver introduces a replica super-regenerative receiver as a method to reject common-mode noise sources, such as supply/substrate coupling, thereby reducing undesired self-oscillations and improving BER. Designed in a 90-nm CMOS process, the test-chip measurements show a sensitivity of -80 dBm at 500 kb/s and -65 dBm at 1 Mb/s, respectively, at a BER less than 10⁻³, with 340 µW total power.


Asunto(s)
Electrónica Médica/instrumentación , Tecnología de Sensores Remotos/instrumentación , Diseño de Equipo , Semiconductores
10.
Acta Crystallogr C ; 68(Pt 8): m209-12, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22850844

RESUMEN

The title compound, [CuNa(C(4)H(3)O(7)S)(C(10)H(8)N(2))(H(2)O)(3)](n), consists of one Cu(II) cation, one Na(I) cation, one 2-sulfonatobutanedioate trianion (SSC(3-)), one 2,2'-bipyridyl (bpy) ligand and three coordinated water molecules as the building unit. The coordination of the Cu(II) cation is composed of two pyridyl N atoms, one water O atom and two carboxylate O atoms in a distorted square-pyramidal coordination geometry with an axial elongation. The Na(I) cation is six-coordinated by three water molecules and three carboxylate O atoms from three SSC(3-) ligands in a distorted octahedral geometry. Two SSC(3-) ligands link two Cu(II) cations to form a Cu(2)(SSC)(2)(bpy)(2) macrocyclic unit lying across an inversion centre, which is further linked by Na(I) cations via Na-O bonds to give a one-dimensional chain. Interchain hydrogen bonds link these chains to form a two-dimensional layer, which is further extended into a three-dimensional supramolecular framework through π-π stacking interactions. The thermal stability of the title compound has also been investigated.

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