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1.
Food Chem ; 367: 130653, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343809

RESUMO

A uniform spherical structure covalent organic framework (TAPA-BPDA-COF) was prepared by a facile method at room temperature with tris(4-aminophenyl)amine (TAPA) and 4,4'-biphenyldicarboxaldehyde (BPDA) as building blocks. Based on the solid phase extraction with the TAPA-BPDA-COF as the sorbent and high performance liquid chromatography-diode array detection, a sensitive analytical method was established for the determination of four neonicotinoid insecticides from water and honey samples. Under the optimum conditions, good linear response for the quantification of the analytes was achieved in the range of 0.3-50.0 ng mL-1 for water samples and in the range of 8.0-500.0 ng g-1 for honey samples. The method recoveries fell in the range of 80.0-121.9% with RSDs less than 7.6%. The limits of detection at the signal to noise ratio of 3 were measured to be in the range of 0.08-0.12 ng mL-1 for water samples and 2.6-3.3 ng g-1 for honey samples, depending on compounds.


Assuntos
Inseticidas , Estruturas Metalorgânicas , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Neonicotinoides , Extração em Fase Sólida
2.
Rev Esp Enferm Dig ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34607443

RESUMO

AIM: To investigate the relationship between TMEM16A and the clinicopathological features and prognosis of patients with colorectal cancer (CRC). METHODS: 96 patients with CRC that were confirmed by pathology after being operated on at the First Affiliated Hospital of Dalian Medical University between June 2009 and December 2011 were enrolled and followed up upon. The expression of TMEM16A protein in CRC was detected by immunohistochemistry in 96 cases. The relationship between the expression of TMEM16A protein in CRC and the clinical features and clinical prognosis were analyzed. RESULTS: 1. There was no correlation between the TMEM16A protein expression and gender, age, or tumor location, size, and degree of differentiation (P>0.05). However, the expression of TMEM16A protein was significantly associated with the depth of invasion, lymph node metastasis, and the Dukes stage (P<0.05). 2. Kaplan-Meier survival curves showed that CRC patients with high expressions of TMEM16A protein had poorer overall survival compared with those having low expression levels (68.2% vs. 92.3%, X2=9.892, P = 0.002). Multivariate Cox regression analysis showed that upregulation of TMEM16A protein expression is an independent predictive factor for poor prognosis in patients with CRC (P<0.05, RR=6.467, 95% CI: 1.777- 23.538). CONCLUSIONS: The expression of TMEM16A protein in CRC was associated with tumor invasion, lymph node metastasis, and the Dukes stage. High expression of TMEM16A protein in CRC can be identified as an independent predictive factor for the poor prognosis of patients with CRC.

4.
Int J Mol Sci ; 22(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34502461

RESUMO

Broomcorn millet (Panicum miliaceum L.) affected by smut (caused by the pathogen Sporisorium destruens) has reduced production yields and quality. Determining the tolerance of broomcorn millet varieties is essential for smut control. This study focuses on the differences in the phenotypes, physiological characteristics, and transcriptomes of resistant and susceptible broomcorn millet varieties under Sporisorium destruens stress. In diseased broomcorn millet, the plant height and stem diameter were reduced, while the number of nodes increased. After infection, the activities of superoxide dismutase and peroxidase decreased, and malondialdehyde and relative chlorophyll content (SPAD) decreased. Transcriptome analysis showed 514 and 5452 differentially expressed genes (DEGs) in the resistant and susceptible varieties, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of DEGs showed that pathways related to plant disease resistance, such as phenylpropanoid biosynthesis, plant-pathogen interaction, and plant hormone signal transduction, were significantly enriched. In addition, the transcriptome changes of cluster leaves and normal leaves in diseased broomcorn millet were analysed. Gene ontology and KEGG enrichment analyses indicated that photosynthesis played an important role in both varieties. These findings lay a foundation for future research on the molecular mechanism of the interaction between broomcorn millet and Sporisorium destruens.

5.
Arch Biochem Biophys ; 711: 109024, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34487720

RESUMO

This study attempted to determine the effect of EphA2 on H2O2-treated lens epithelial cells (SRA01/04) and the underlying mechanisms. MTT assay and flow cytometry were performed to assess cell viability and cell apoptosis. Western blot was carried out to examine the levels of proteins associated with apoptosis and autophagy. Our results revealed that EphA2 significantly elevated the reduced cell viability, and inhibited the increased cell apoptosis in H2O2-treated SRA01/04 cells, along with the significant up-regulated Bcl-2 and down-regulated Cleaved-caspase-3 and Bax protein levels, but which were all abolished by Rapa (autophagy activator). We also found that EphA2 significantly suppressed cell autophagy in H2O2-treated SRA01/04 cells. Additionally, EphA2 significantly up-regulated the protein levels of p-Akt and p-mTOR in H2O2-treated SRA01/04 cells, and the inhibition of Akt by MK-2206 and inhibition of mTOR by Rapa both obviously reversed EphA2-mediated the inhibition of autophagy in H2O2-treated SRA01/04 cells. In summary, these data demonstrated that EphA2 inhibited the apoptosis of SRA01/04 cells by inhibiting autophagy via activating PI3K/Akt/mTOR pathway.

6.
Endocrinol Diabetes Nutr (Engl Ed) ; 68(5): 329-337, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34556263

RESUMO

Saponins are the main bioactive substances with anti-hyperglycemic activities of Momordica charantia. This study aimed to verify the effects of M. charantia saponins on insulin secretion and explore the potential underlying mechanisms in INS-1 pancreatic ß-cells. We injured INS-1 cells with 33.3mM glucose and then treated them with saponins. Saponins improved cell morphology and viability as demonstrated by inverted microscopy and CCK8 detection and significantly increased insulin secretion in a concentration-dependent manner as shown by ELISA. Thus, we obtained the optimal concentration for the subsequent experiments. Potential mechanisms were explored by immunofluorescence, western blotting, and RT-qPCR techniques. First, saponins increased the mRNA and protein levels of IRS-2 but decreased the serine 731 phosphorylation level of IRS-2. Moreover, saponins increased the phosphorylation of Akt protein and decreased the protein level of FoxO1, which were both reversed by the PI3K inhibitor ly294002. Furthermore, saponins increased the protein level of the downstream molecule and insulin initiating factor PDX-1, which was also reversed by ly294002. Saponins also increased Akt and PDX-1 mRNA and decreased FoxO1 mRNA, which were both reversed by ly294002. Saponins increased glucose-stimulated insulin secretion (GSIS) and intracellular insulin content, which were reversed by ly294002, as determined by ELISA. The immunofluorescence results also confirmed this tendency. In conclusion, our findings improve our understanding of the function of saponins in INS-1 pancreatic ß-cells and suggest that saponins may increase insulin secretion via the PI3K/Akt/FoxO1 signaling pathway.

7.
Sensors (Basel) ; 21(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34577265

RESUMO

Today, vehicles are increasingly being connected to the Internet of Things, which enables them to obtain high-quality services. However, the numerous vehicular applications and time-varying network status make it challenging for onboard terminals to achieve efficient computing. Therefore, based on a three-stage model of local-edge clouds and reinforcement learning, we propose a task offloading algorithm for the Internet of Vehicles (IoV). First, we establish communication methods between vehicles and their cost functions. In addition, according to the real-time state of vehicles, we analyze their computing requirements and the price function. Finally, we propose an experience-driven offloading strategy based on multi-agent reinforcement learning. The simulation results show that the algorithm increases the probability of success for the task and achieves a balance between the task vehicle delay, expenditure, task vehicle utility and service vehicle utility under various constraints.


Assuntos
Algoritmos , Aprendizagem , Simulação por Computador , Internet , Probabilidade
8.
Int J Biol Macromol ; 190: 999-1006, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34487782

RESUMO

In this work, binding interaction between molybdenum disulfide quantum dots (MoS2 QDs) and human serum albumin (HSA) was researched deeply to dissect the conformational variation and fibrillation of HSA affected by MoS2 QDs. The results revealed that MoS2 QDs bound strongly with HSA with molar ratio of 1:1 under the joint actions of hydrogen bond and van der Waals force, leading to the static fluorescence quenching of HSA. MoS2 QDs caused the secondary structure transition of HSA from α-helix stepwise to ß-turn, ß-sheet, and random coil gradually. MoS2 QDs reduced both the molar enthalpy change and the melting temperature of HSA, reducing the thermal stability of HSA significantly. It is worth noting that MoS2 QDs inhibited the fibrillation process of HSA according to the reduced hydrophobic environment and the disturbance of disulfide bonds in HSA network structure. These results reveal the precise binding mechanism of MoS2 QDs with HSA at molecular level, providing indispensable information for the potential application of MoS2 QDs in biological fields.

9.
Ecotoxicol Environ Saf ; 224: 112669, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34419643

RESUMO

Cadmium (Cd) pollution highly threatens food security and human health, and phytoremediation with Cd-tolerant plants is a cost-effective in situ method for remediation of Cd contamination. Broomcorn millet is known for its strong abiotic stress resistance and can be used as a pioneer crop in both marginal regions and newly reclaimed land. To evaluate their potential in remediation of Cd contamination, a total of 288 broomcorn millet core collections were investigated under hydroponic conditions to compare their capabilities in Cd tolerance, translocation, and accumulation. The core collections varied considerably in their growth parameters, Cd concentration, Cd translocation factor, Cd bioaccumulation factor, and Cd accumulation under Cd stress. According to the Cd tolerance index (TI) values, 160 varieties were Cd tolerant. The Cd TI was significantly positively correlated with Cd accumulation, and the shoot Cd concentrations of five Cd-tolerant varieties were more than 100 mgkg-1, the threshold for being Cd hyperaccumulators. Moreover, the concentrations of essential metal elements were significantly decreased in shoots, and Cd concentration had a significantly positive relationship with magnesium (Mg) and zinc (Zn) concentrations in roots under Cd stress. These results demonstrate that broomcorn millet shows considerable tolerance to Cd stress and great differences in Cd accumulation abilities among varieties. Accordingly, broomcorn millet is a promising plant species for Cd bioremediation, with valuable varieties that have been identified for further study on Cd tolerance mechanisms and the remediation of Cd contamination.

10.
Micromachines (Basel) ; 12(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357211

RESUMO

Focusing on service control factors, rapid changes in manufacturing environments, the difficulty of resource allocation evaluation, resource optimization for 3D printing services (3DPSs) in cloud manufacturing environments, and so on, an indicator evaluation framework is proposed for the cloud 3D printing (C3DP) order task execution process based on a Pareto optimal set algorithm that is optimized and evaluated for remotely distributed 3D printing equipment resources. Combined with the multi-objective method of data normalization, an optimization model for C3DP order execution based on the Pareto optimal set algorithm is constructed with these agents' dynamic autonomy and distributed processing. This model can perform functions such as automatic matching and optimization of candidate services, and it is dynamic and reliable in the C3DP order task execution process based on the Pareto optimal set algorithm. Finally, a case study is designed to test the applicability and effectiveness of the C3DP order task execution process based on the analytic hierarchy process and technique for order of preference by similarity to ideal solution (AHP-TOPSIS) optimal set algorithm and the Baldwin effect.

11.
Transl Psychiatry ; 11(1): 441, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429396

RESUMO

The majority of smokers relapse even after successfully quitting because of the craving to smoking after unexpectedly re-exposed to smoking-related cues. This conditioned craving is mediated by reward memories that are frequently experienced and stubbornly resistant to treatment. Reconsolidation theory posits that well-consolidated memories are destabilized after retrieval, and this process renders memories labile and vulnerable to amnestic intervention. This study tests the retrieval reconsolidation procedure to decrease nicotine craving among people who smoke. In this study, 52 male smokers received a single dose of propranolol (n = 27) or placebo (n = 25) before the reactivation of nicotine-associated memories to impair the reconsolidation process. Craving for smoking and neural activity in response to smoking-related cues served as primary outcomes. Functional magnetic resonance imaging was performed during the memory reconsolidation process. The disruption of reconsolidation by propranolol decreased craving for smoking. Reactivity of the postcentral gyrus in response to smoking-related cues also decreased in the propranolol group after the reconsolidation manipulation. Functional connectivity between the hippocampus and striatum was higher during memory reconsolidation in the propranolol group. Furthermore, the increase in coupling between the hippocampus and striatum positively correlated with the decrease in craving after the reconsolidation manipulation in the propranolol group. Propranolol administration before memory reactivation disrupted the reconsolidation of smoking-related memories in smokers by mediating brain regions that are involved in memory and reward processing. These findings demonstrate the noradrenergic regulation of memory reconsolidation in humans and suggest that adjunct propranolol administration can facilitate the treatment of nicotine dependence. The present study was pre-registered at ClinicalTrials.gov (registration no. ChiCTR1900024412).


Assuntos
Propranolol , Tabagismo , Sinais (Psicologia) , Humanos , Masculino , Memória , Nicotina , Fumantes , Tabagismo/tratamento farmacológico
12.
Mol Ecol Resour ; 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34233085

RESUMO

Phylogenetic trees have been extensively used in community ecology. However, how the phylogeny construction affects ecological inferences is poorly understood. In this study, we constructed three different types of phylogenetic trees (a synthetic-tree generated using V.PhyloMaker, a barcode-tree generated using rbcL+matK+trnH-psbA, and a plastome-tree generated from plastid genomes) that represented an increasing level of phylogenetic resolution among 580 woody plant species from six forest dynamic plots in subtropical evergreen broadleaved forests of China. We then evaluated the performance of each phylogeny in estimations of community phylogenetic structure, turnover and phylogenetic signal in functional traits. As expected, the plastome-tree was most resolved and most supported for relationships among species. For local phylogenetic structure, the three trees showed consistent results with Faith's PD and MPD; however, only the synthetic-tree produced significant clustering patterns using MNTD for some plots. For phylogenetic turnover, contrasting results between the molecular trees and the synthetic-tree occurred only with nearest neighbor distance. The barcode-tree agreed more with the plastome-tree than the synthetic-tree for both phylogenetic structure and turnover. For functional traits, both the barcode-tree and plastome-tree detected phylogenetic signal in maximum height, but only the plastome-tree detected signal in leaf width. This is the first study that uses plastid genomes in large-scale community phylogenetics. Our results highlight the improvement of plastome-trees over barcode-trees and synthetic-trees for the analyses studied here. Our results also point to the possibility of type I and II errors in estimation of phylogenetic structure and turnover and detection of phylogenetic signal when using synthetic-trees.

14.
Comput Intell Neurosci ; 2021: 1560972, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34326864

RESUMO

In recent years, artificial intelligence supported by big data has gradually become more dependent on deep reinforcement learning. However, the application of deep reinforcement learning in artificial intelligence is limited by prior knowledge and model selection, which further affects the efficiency and accuracy of prediction, and also fails to realize the learning ability of autonomous learning and prediction. Metalearning came into being because of this. Through learning the information metaknowledge, the ability to autonomously judge and select the appropriate model can be formed, and the parameters can be adjusted independently to achieve further optimization. It is a novel method to solve big data problems in the current neural network model, and it adapts to the development trend of artificial intelligence. This article first briefly introduces the research process and basic theory of metalearning and discusses the differences between metalearning and machine learning and the research direction of metalearning in big data. Then, four typical applications of metalearning in the field of artificial intelligence are summarized: few-shot learning, robot learning, unsupervised learning, and intelligent medicine. Then, the challenges and solutions of metalearning are analyzed. Finally, a systematic summary of the full text is made, and the future development prospect of this field is assessed.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Big Data , Aprendizado de Máquina
16.
J Colloid Interface Sci ; 602: 810-821, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34157516

RESUMO

Although more and more attention has been paid to electromagnetic interference (EMI) shielding fabric materials due to increasing electromagnetic waves pollution, little attention to their fire safety behavior and durability in practical use. Herein, durable EMI shielding ramie fabric with flame retardant and self-healing performance were fabricated by depositing ammonium polyphosphate (APP)/polyethyleneimine (PEI) layer, MXene sheets and polycaprolactone (PCL) layer. The resultant multifunctional fabric could self-extinguish and the peak heat release rate (pHRR) value reduced about 74.3% for the modified ramie fabric that contains about 12 wt% of PEI/APP bilayer compared with pure ramie fabric. Furthermore, the ramie fabric coated by a increasing amount of MXene sheets changed from insulating to conductive, thus gradually improving their EMI shielding performance, which exhibit a high electrical conductivity of 900.56 S/m with an outstanding SE value of 35 dB at a 1.2 mg/cm2 content in the X-band. Besides, When the multifunctional fabric was cut off under external force, it could achieve self-healing and the EMI shielding performance can recover to 34 dB due to the low melting point and good fluidity of PCL. Thus, this multifunctional fabric holds great promise for wearable intelligent cloth, EMI shielding and other fields.


Assuntos
Boehmeria , Retardadores de Chama , Condutividade Elétrica , Polifosfatos , Têxteis
17.
Glob Chang Biol ; 27(17): 4196-4206, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34101948

RESUMO

A consensus about the fire-related soil carbon (C) and nitrogen (N) impacts that determine soil health and ecosystem services at the global scale remains elusive. Here, we conducted a global meta-analysis of 3173 observations with 1444, 1334, 228, and 167 observations for soil C, N, pyrogenic C (PyC), and the percent of PyC to total organic C (PyC/TOC) from 296 field studies. Results showed that fire significantly decreased soil C (-15.2%) and N (-14.6%) but increased soil PyC (40.6%) and PyC/TOC (30.3%). Stronger negative fire impacts on soil C and N were found in tropical and temperate climates than in Mediterranean and subtropical climates; stronger effects were found in forest ecosystems than in non-forest ecosystems. Wildfire and high-severity fire led to greater soil C and N losses than prescribed and low-severity fires, respectively, while they promoted greater increases in soil PyC and PyC/TOC than prescribed and low-severity fires, respectively. However, soil C and N recovered to control levels approximately 10 years after fire, which is a shorter period than previously determined. These results suggest that fire-induced PyC production should be accounted for in the C budget under global change. These results will improve our knowledge of the spatiotemporal variability of fire effects on soil C and N storage and have implications for fire management and ecosystem recovery.


Assuntos
Incêndios , Solo , Carbono , Ecossistema , Florestas , Nitrogênio
18.
Cancer Lett ; 518: 49-58, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34139284

RESUMO

Oncolytic viruses as cancer vaccines modulate the tumor microenvironment and act synergistically with immune checkpoint inhibitors to overcome resistance. Taking advantage of the loading capacity for exogenous genes, we generated a recombinant herpes simplex virus type 1 (HSV-1), HSV-aPD-1, carrying a full-length humanized anti-PD-1 monoclonal antibody (anti-PD-1 mAb) that replicates and expresses anti-PD-1 mAbs in tumor cells in vitro and in vivo. Its anti-tumor effect was assessed in human PD-1 knock-in mice by analyzing tumor inhibition, cell populations and RNA expression in tumors, and serum cytokine levels. Enhanced anti-tumor immune responses and T-cell infiltration were induced by HSV-aPD-1 compared with unloaded virus or anti-PD-1 therapy in both MC38 and B16-F10 models, resulting in improved treatment efficacy in the latter. Moreover, compared with unloaded HSV-1 or HSV-1 loaded with GM-CSF/IL-2 combined with anti-PD-1 mAbs, HSV-aPD-1 displayed similar therapeutic control of tumor growth. Finally, tumor RNAseq analysis in the B16-F10 model showed upregulated IFN pathway and antigen processing and presentation genes, and downregulated angiogenesis and cell adhesion genes, which all contribute to tumor inhibition. These findings indicate the clinical potential of HSV-aPD-1 as monotherapy or combination therapy, especially in tumors resistant to immune checkpoint inhibitors.

19.
Bull Environ Contam Toxicol ; 107(4): 693-699, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34100971

RESUMO

Microplastic pollution to the marine environment is a global issue. This study investigated microplastic pollution in ten species of different mollusks. Microplastic shape and size were determined under a microscope. Additionally, the polymer types were identified using Fourier transform infrared microspectroscopy (µ-FT-IR). The results showed that the microplastic abundance varied from 0.19 to 1.76 items/g (wet weight) and 4.3 to 36.6 items/individual. Four types of microplastics were observed, including fibers, fragments, films, and pellets. Fibers smaller than 500 µm were the most common. Cellophane (CP) and polyethylene terephthalate (PET) were the main polymer types. The microplastic abundance in the buried bivalve Ruditapes philippinarum demonstrated the highest level of microplastic contamination assessed by wet weight (1.76 ± 0.95 items/g). Furthermore, the Spearman correlation test showed that there was a significant negative correlation between the microplastic abundance calculated by weight and the biometric parameters (shell length, shell height and soft tissue wet weight). Our results will provide valuable information for assessment of the potential health risks of microplastics in China's seafood.

20.
J Chromatogr A ; 1651: 462301, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34107399

RESUMO

In this work, a core-shell structured magnetic covalent organic framework named as M-TpDAB was constructed with 3,3'-diaminobenzidine (DAB) and 1,3,5-triformylphloroglucinol (Tp) as building units. M-TpDAB was characterized by infrared spectroscopy, nitrogen adsorption-desorption isotherms, powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Using the M-TpDAB as adsorbent, a simple and highly effective method was proposed for preconcentrating phenylurea herbicides before high performance liquid-phase chromatography analysis. In the optimized conditions, a good linearity was achieved within the range of 0.15-100 ng mL-1 for water sample, 1.0-100.0 ng mL-1 for tea drink samples. The limits of detection for the analytes were 0.05-0.15 ng mL-1 for water sample and 0.30-0.50 ng mL-1 for drink samples. Satisfactory recoveries of spiked target compounds were in the range of 84.6%-105% for water sample and 80.3%-102% for tea drink samples. Finally, the M-TpDAB based method was successfully used to determine phenylurea herbicides in tea drinks and water samples, demonstrating a good alternative for analyzing trace level of phenylurea herbicides in water samples.


Assuntos
Herbicidas/isolamento & purificação , Estruturas Metalorgânicas/química , Compostos de Fenilureia/isolamento & purificação , Extração em Fase Sólida/métodos , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão , Água Potável/química , Herbicidas/análise , Fenômenos Magnéticos , Magnetismo/métodos , Compostos de Fenilureia/análise , Difração de Raios X
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