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1.
Environ Res ; : 112210, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34656636

RESUMO

Groundwater is the major source of water for drinking and irrigation purposes in and around Hua County, Shaanxi Province, China. The main purposes of this research is to evaluate the groundwater quality in the rainy and dry seasons of Hua County and analyze the causes of seasonal differences and determine the areas with serious pollution. Groundwater quality was assessed in this study using entropy water quality index (EWQI) and some graphical approaches such as Gibbs and Piper diagrams. The contour maps of groundwater quality were drawn by Geographical Information System (GIS). According to the obtained results, the locations where groundwater quality was rated as excellent or good in both wet and dry seasons were mainly in the north and east of the research area. COD and NO3- are the parameters that have the most serious negative effect on water quality. The dominant factors influencing groundwater chemical evolution in the study area were rock weathering and dissolution, and the precipitation and evaporation during the wet and dry seasons do not cause significant changes in groundwater chemistry. Adults' health risks results revealed that 27.69% and 52.31% of the groundwater samples exceeded the acceptable limit for non-carcinogenic risk in the wet and dry season, respectively, while for children the ratios are 30.16% and 47.62%, respectively. The contributive percentages of nitrate, fluoride and nitrate to the total risk are 61.29%, 28.71% and 10.00% in the wet season and 68.84%, 20.85% and 10.31% in the dry season. The risk is higher in the south than in the north of the study area, and is especially high in the southwest of the study area.

2.
Carbohydr Polym ; 273: 118569, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560980

RESUMO

Cellulose films with biodegradability and intrinsically antistatic property have many applications. However, conventional cellulose films show poor toughness and UV-shielding property, and the major sources are high-grade cotton linter or wood pulp. Herein, by using low-cost waste cotton textiles as the raw materials, we successfully fabricated transparent cellulose/aramid nanofibers (ANFs) films, in which in-situ retained ANFs had a diameter of 20-30 nm and a length of several micrometers. Because ANFs and cellulose chains formed strong hydrogen bonding interactions, the tensile strength and elongation of the resultant cellulose/ANFs film with 1.0 wt% ANFs could reach 54.4 MPa and 15.8%, respectively, increased by 63.4% and 154% compared to those of pure cellulose film (33.3 MPa and 6.2%). Meanwhile, the cellulose/ANFs films show excellent UV-shielding properties and irradiation stability. Hence, the novel cellulose/ANFs films with improved mechanical and UV-shielding performance were in-situ prepared leading to enhance the valorization of waste cotton textiles.

3.
Talanta ; 235: 122747, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517615

RESUMO

Microchip capillary electrophoresis (MCE) is a powerful technique for rapid separation; however, its acceptance in routine laboratories is still limited. Compromises caused by the efforts for solving different problems, such as reducing its cost of fabrication and ensuring high separation efficiency, undermine the competitiveness of this technology compared to other separation techniques. Contrary to the conventional pursuit of narrow microchannels, this study investigated the suitability of microchips with channels at the sub-millimeter level, targeting the simplification of the overall operation, cost reduction, and robustness improvement. To this effect, we considered the influence of pressurized flow and Joule heating on the separation. The suppression of pressurized flow with viscous solutions was confirmed through a combination of simulations and experimental results, indicating that the buffer viscosity was enough for successful separation. We fabricated channels of 200 µm × 230 µm using computer numerical controlled (CNC) machining and obtained theoretical plate numbers of 4.8 × 105 m-1 and 5.3 × 105 m-1 for fluorescein isothiocyanate (FITC) labeled small molecules and DNA fragments, respectively, with a buffer viscosity of 168 mPa s (0.5 % hydroxypropyl methylcellulose, HPMC). These values are comparable with that of narrow-bore microchips. Furthermore, we did not observe any deleterious effects with low-conductivity buffers. We investigated the rapid and highly sensitive detection of mycoplasma contamination and the real samples of circulating cell-free DNA (cfDNA), which gave a limit of detection (LOD) as low as 2.3 ng mL-1. Owing to the significant reduction in cost, ease of operation, and fast separation capabilities demonstrated in this work, MCE can be a viable alternative to the usual slab gel electrophoresis running in most biological laboratories.


Assuntos
Eletroforese em Microchip , DNA , Eletroforese Capilar , Derivados da Hipromelose , Limite de Detecção
4.
J Hazard Mater ; 417: 125986, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-33990038

RESUMO

Sensitive, convenient and rapid detection devices for toxic Cr(VI) suitable for filed use are required. Smartphone can be used as the detector, but the quality of images taken with a smartphone may depend on the ambient light and the operator. In this work, two types of low-cost and portable smartphone-based devices used for fluorescence spots brightness and size dual-mode detection of Cr(VI) were constructed with the aid of the 3D printing, which avoids the effect of ambient light and maintains a fixed position of the phone camera relative to the samples. Based on the brightness reflected by the blue channel of RGB values of the images of carbon nanodots, a linear relationship between quenching efficiency and concentration of Cr(VI) in a range of 0.2-150 µM with a limit of detection of 0.058 µM was attained, which is comparable to or better than that from fluorescence spectrometers. With the size variation of fluorescence spots, a linear range of 10-350 µM was acquired and it is more intuitive for direct naked-eye estimation of the concentration of Cr(VI). The applicability of the proposed devices for the detection of Cr(VI) was verified with water and soil samples with recoveries ranging in 95.0-108.2%.


Assuntos
Pontos Quânticos , Carbono , Cromo , Smartphone
5.
J Cancer ; 11(16): 4783-4790, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32626525

RESUMO

Background: LncRNAs has been shown to play important roles in the progression of lung cancer, but it remains poorly understood whether lncRNAs affect the occurrence and development of lung cancer by regulating autophagy and apoptosis levels. Here, we investigated the roles of PANDAR in NSCLC. Materials and Methods: The expression profile and clinical application of PANDAR and its possible target gene BECN1 were tested in 276 cases of lung cancer tissues. Through some actual experiments, we explored functions of PANDAR about proliferation, apoptosis and autophagy of NSCLC cells in vitro. Results: PANDAR was found to downregulate both in lung cancer tissues and cell lines compared with corresponding controls (P < 0.05 for all), which was related to tumor stage (P < 0.05). Moreover, autophagy related gene BECN1 was also downregulated in lung cancer tissues comparison with normal tissues (P < 0.01), and there was a significant positive correlation between PANDAR and BECN1 levels (r = 0.789, P < 0.001). So, the high expression of PANDAR increased BECN1 expression levels and impaired the proliferation of NSCLC cell lines in vitro. Furthermore study showed PANDAR could regulate cell autophagy and apoptosis levels. Conclusion: These results indicated lncRNA PANDAR was a tumor suppressor and can inhibit NSCLC cell proliferation by activating autophagy and apoptosis pathways via upregulation of BECN1 expression.

6.
Electrophoresis ; 41(15): 1273-1279, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32358896

RESUMO

Mutations in the potassium channel genes may be linked to the development of epilepsy and affect the blood potassium levels. Therefore, accurate determination of potassium in the blood will be critical to diagnose the cause of epilepsy. CE is a competent technique for the fast detection of multiple ions, but complicated matrices of a blood sample may cause significant variation of migration times and the peak shape. In this work, a procedure for rapid stabilization of the capillary inner surface through preflushing of a blood sample was employed. The process takes only 40 min for a capillary and then it can be used for more than 2 weeks. No pretreatment of the blood sample or other surface modification of the capillary is needed for the analysis. The RSDs of the migration time and peak area were reduced to 1.5 and 5.1% from 12.6 and 14.5%, respectively. The proposed method has been successfully applied to the determination of the potassium contents in the blood sample of patients with epilepsy at different stages. The recoveries of potassium ions in these blood samples are in a range from 86.5 to 104.5%.


Assuntos
Eletroforese Capilar/métodos , Epilepsia/diagnóstico , Potássio/sangue , Coleta de Amostras Sanguíneas , Humanos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
7.
ISA Trans ; 97: 241-250, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31300159

RESUMO

Remaining useful life (RUL) prediction is very important for improving the availability of a system and reducing its life cycle cost. This paper proposes a deep long short-term memory (DLSTM) network-based RUL prediction method using multiple sensor time series signals. The DLSTM model fuses multi-sensor monitoring signals for accurate RUL prediction, which is able to discover the hidden long-term dependencies among sensor time series signals through deep learning structure. By grid search strategy, the network structure and parameters of the DLSTM are efficiently tuned using an adaptive moment estimation algorithm so as to realize an accurate and robust prediction. Two various turbofan engine datasets are adopted to verify the performance of the DLSTM model. The experimental results demonstrate that the DLSTM model has a competitive performance in comparison with state-of-the-arts reported in literatures and other neural network models.

8.
Sensors (Basel) ; 19(12)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248106

RESUMO

Accurate and timely bearing fault diagnosis is crucial to decrease the probability of unexpected failures of rotating machinery and improve the efficiency of its scheduled maintenance. Since convolutional neural networks (CNN) have poor feature extraction capability for sensor data with 1D format, CNN combined with signal processing algorithm is often adopted for fault diagnosis. This increases manual conversion work and expertise dependence while reducing the feasibility and robustness of the corresponding fault diagnosis method. In this paper, a novel sensor data-driven fault diagnosis method is proposed by fusing S-transform (ST) algorithm and CNN, namely ST-CNN. First of all, a ST layer is designed based on S-transform algorithm. In the ST layer, sensor data is automatically converted into 2D time-frequency matrix without manual conversion work. Then, a new ST-CNN model is constructed, and the time-frequency coefficient matrixes are inputted into the constructed ST-CNN model. After the training process of the ST-CNN model is completed, the classification layer such as softmax performs the fault diagnosis. Finally, the diagnosis performance of the proposed method is evaluated by using two public available datasets of bearings. The experimental results show that the proposed method performs the higher and more robust diagnosis performance than other existing methods.

9.
Talanta ; 201: 16-22, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122407

RESUMO

Diode lasers, especially 405 nm diode laser, as excitation sources offer new opportunities for laser-induced fluorescence (LIF) detection, but the lack of available derivatization reagents limits their widespread applications. Herein, a commercial fluorescent dye, 7-(diethylamino)coumarin-3-carboxylic acid (DEAC-C) was introduced as derivatization reagent and corresponding derivatization strategy for DEAC-C labeling sulfonamides was developed for 405 nm LIF detection. After systematic optimization, three sulfonamides including hydrochlorothiazide (HCTZ), chlorothiazide (CTZ) and chlortalidone (CTD) could be efficiently labeled by DEAC-C in the presence of cyanuric chloride and triethylamine (1.5%) in acetonitrile at 50 °C for 180 min. Based on the laboratory-built capillary electrophoresis-LIF system, a robust method was then proposed for the separation of DEAC-C labeled sulfonamides by micellar electrokinetic chromatography (MEKC) using the classic borax-SDS system. Under the optimized conditions, a baseline separation of three sulfonamides was achieved within 15 min, and the detection limits were determined to be 0.24, 0.29, and 0.23 nM for HCTZ, CTZ, and CTD, respectively. Furthermore, the developed MEKC-LIF method was validated using sulfonamide standards and spiked human urine sample and successfully applied for the analysis of three sulfonamides in complex pharmaceutical and physiological samples.

10.
Environ Sci Pollut Res Int ; 24(32): 24844-24855, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28914413

RESUMO

This article used novel non-magnetized and magnetized biochars prepared under a CO2 atmosphere returned to Cd-contaminated soil and compared these to the effects of conventional biochars prepared under a N2 atmosphere with regard to Cd-contaminated soil remediation. A pot experiment with lettuce (Lactuca sativa) was conducted to investigate the relative soil remediation effects of these biochars. The soil used for the pot experiment was spiked with 20 mg kg-1 Cd and amended with 5% of a biochar before sowing. Through these research works, some important results were obtained as follows: (1) applying biochar treated by pyrolysis under a CO2 atmosphere can obtain the best remediation effect of Cd-contaminated soil that the content of cadmium in the lettuce roots, stems, and leaves was reduced 67, 62, and 63%, respectively; (2) the magnetic biochar aggregation for the soil is weak, so the heavy metal cadmium in the soil could not be immobilized well by the magnetic biochar; (3) The remediation mechanism of novel biochars is that biochar includes a large number of organic functional groups (-C-OH, -C=O, COO-) that can act in a complexing reaction with heavy metal Cd(II) and the inorganic salt ions (Si, S, Cl, etc.) that can combine with cadmium and generate a stable combination.


Assuntos
Cádmio/análise , Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Fenômenos Magnéticos , Poluentes do Solo/análise , Biodegradação Ambiental , Recuperação e Remediação Ambiental/instrumentação , Alface/metabolismo
11.
Tumour Biol ; 39(5): 1010428317706208, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28488546

RESUMO

Numerous studies suggested that long non-coding RNA UCA1 was highly expressed and played critical roles in the development and progression of various cancerous tissues and cells. However, little is known about the association between UCA1 and tumor lymph node metastasis. In our study, a systematic review was conducted to evaluate the association between UCA1 expression and tumor lymph node metastasis and explore whether UCA1 can be a potential molecular marker for predicting the multiple tumor lymph node metastasis. The meta-analysis result showed that the number of lymph node metastasis in different tumorous types of UCA1 high-expression group was significantly higher compared with UCA1 low-expression group (pooled odds ratio = 2.13, 95% confidence interval: 1.60-2.84, p < 0.05). To verify whether the above result was still valid in specific tumor type, we conducted a meta-analysis including four articles on colorectal cancer (pooled odds ratio = 2.07, 95% confidence interval: 1.28-3.34, p < 0.05). Based on the existing results, it can be explained that the long non-coding RNA UCA1 was significantly associated with lymph node metastasis and both the results revealed that compared with UCA1 low-expression group, the lymph node metastasis rate of UCA1 high-expression group was statistically significantly elevated. Therefore, long non-coding RNA UCA1 has the potential of being a biological marker for predicting lymph node metastasis.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias Colorretais/genética , RNA Longo não Codificante/biossíntese , Biomarcadores Tumorais/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Prognóstico , RNA Longo não Codificante/genética
12.
J Ethnopharmacol ; 198: 291-301, 2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28088494

RESUMO

ETHNO-PHARMACOLOGICAL RELEVANCE: Hibiscus rosa-sinensis L. (HRS), a folk medicine named Zhujin in China, possess anti-tumor, antioxidant, antibacterial, low density lipoprotein oxidation prevention and macrophage death prevention effects. The leaves and red flowers of HRS have been traditionally used to treat with furuncle and ulceration. AIM OF THE STUDY: To investigate the efficacy and possible mechanism of the N-butyl alcohol extract of HRS (NHRS) red flowers in wound healing by analyzing the collagen fiber deposition, angiogenic activity and macrophages action of the NHRS. MATERIALS AND METHODS: In an excisional wound healing model in rats, different concentrations of NHRS, or recombinant bovine basic fibroblast growth factor (rbFGF), were respectively applied twice daily for 9 days. Histopathology was assessed on day 9 via hematoxylin and eosin (HE) and Masson's trichrome (MT) staining, and immunohistochemistry for vascular endothelial growth factor (VEGF), transforming growth factor-ß1 (TGF-ß1) and CD68. Immunomodulation by NHRS was evaluated by a carbon clearance test in mice. RESULTS: Wound healing post-surgery was greater in the rbFGF-control, NHRS-M and MHRS-H groups than in the model and 5% dimethylsulfoxide (DMSO)-control groups after the third day. By the sixth day the wound contraction of NHRS-M and MHRS-H groups was much higher than the rbFGF-control group. HE and MT staining revealed that epithelialization, fibroblast distribution, collagen deposition of NHRS-M- and NHRS-H-control groups were significantly higher than the model group. Moreover, immunohistochemistry showed more intense staining of VEGF, TGF-ß1 and CD68 in the rbFGF- and NHRS-control groups, compared to that in model and 5% DMSO-control groups. The clearance and phagocytic indices of NHRS-M- and NHRS-H-control groups were significantly higher than that of the carboxyl methyl cellulose (CMC) group in mice. CONCLUSION: NHRS accelerates wound repair via enhancing the macrophages activity, accelerating angiogenesis and collagen fiber deposition response mediated by VEGF and TGF-ß1.


Assuntos
Hibiscus/química , Neovascularização Fisiológica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , 1-Butanol/química , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Bovinos , Colágeno/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Fator 2 de Crescimento de Fibroblastos/farmacologia , Flores , Masculino , Camundongos , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Biosens Bioelectron ; 92: 536-541, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27838204

RESUMO

As a novel "turn on" fluorescent probe, 4-((1Z,3Z)-1,4-bis(4-(methoxycarbonyl)phenyl)-4-(pyridin-4-yl)buta-1,3-dien-1-yl)-1-methylpyridin-1-ium hexafluorophosphate (TABD-Py-PF6) with an aggregation-induced emission characteristic was synthesized for in-situ quantitation of γ-globulins in the blood serum. It was shown that the TABD-Py-PF6 probe was highly specific for γ-globulins and that other components in the blood serum, including serum albumins, fibrinogen, glucose, urea, and cholesterol, barely interfered with the molecular interactions between TABD-Py-PF6 and γ-globulins. The high specificity of this probe enabled in-situ quantitative detection of γ-globulins without isolation of γ-globulins from the blood serum. The fluorescence intensity of TABD-Py-PF6 was linearly correlated with the concentration of γ-globulins in the ranges of 7.89-300µg/mL. The detection limit of γ-globulins was determined to be 7.89µg/mL. The fluorescence response time of TABD-Py-PF6 for detecting γ-globulins was very short (below 5s), allowing for real-time detection. The mechanism of the fluorescent turn-on behavior of the TABD-Py-PF6 probe was investigated and electrostatic interactions between TABD-Py-PF6 and γ-globulins were identified.


Assuntos
Corantes Fluorescentes/química , Compostos de Piridínio/química , Espectrometria de Fluorescência/métodos , gama-Globulinas/análise , Técnicas Biossensoriais/métodos , Humanos , Limite de Detecção , Modelos Moleculares
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