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1.
Dalton Trans ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36662484

RESUMO

The combination of DNA nanotechnology and nanopore sensing technology has greatly promoted research on target molecule or ion detection. The large solid-state nanopores/nanochannels show better mechanical stability and reproducibility, but metal ion detection in the large nanopores with diameters of hundreds of nanometers or several micrometers is rarely reported. Hence, it is meaningful and urgent to develop a large nanopore-based sensing platform for the detection of metal ions. Herein, we employed a salicylic aldehyde-modified DNA network in conjunction with a glass nanopipette (GN) with a diameter of hundreds of nanometers as a sensing platform for the detection of target metal ions. Upon the addition of different receptors with the amino group, the salicylic aldehyde could in situ specifically recognize and bind with Zn2+ and Al3, forming Schiff base-metal ion complexes at the four vertices of one face per nanocube unit. The steric hindrance effect of multiple Schiff bases and metal ion complexes leads to the blockage of internal structure and decrease of ion current in the GN. Owing to this signal amplification strategy, the detection limit of the target metal ion reaches a level of fM in the GN with a diameter of about 300 nm. In the future, this functional nanopore sensing platform is expected to realize highly sensitive detection for more biological metal ions by choosing appropriate receptors.

2.
AMB Express ; 13(1): 7, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36656394

RESUMO

As an indispensable enzyme for the hydrolysis of dextran, dextranase has been widely used in the fields of food and medicine. It should be noted that the weak thermostability of dextranase has become a restricted factor for industrial applications. This study aims to improve the thermostability of dextranase AoDex in glycoside hydrolase (GH) family 49 that derived from Arthrobacter oxydans KQ11. Some mutants were predicted and constructed based on B-factor analysis, PoPMuSiC and HotMuSiC algorithms, and four mutants exhibited higher heat resistance. Compared with the wild-type, mutant S357P showed the best improved thermostability with a 5.4-fold increase of half-life at 60 °C, and a 2.1-fold increase of half-life at 65 °C. Furthermore, S357V displayed the most obvious increase in enzymatic activity and thermostability simultaneously. Structural modeling analysis indicated that the improved thermostability of mutants might be attributed to the introduction of proline and hydrophobic effects, which generated the rigid optimization of the structural conformation. These results illustrated that it was effective to improve the thermostability of dextranase AoDex by rational design and site-directed mutagenesis. The thermostable mutant of dextranase AoDex has potential application value, and it can also provide references for engineering other thermostable dextranases of the GH49 family.

3.
Huan Jing Ke Xue ; 44(1): 540-548, 2023 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-36635842

RESUMO

In this study, rice straw, soybean straw, wheat straw, and corn straw were chosen as raw materials, and biochars were prepared through the pyrolysis method at 550℃ under oxygen-limited conditions to investigate the physicochemical properties of biochars derived from the straws, the migration and transformation characteristics of heavy metals (HMs) (Cr, Ni, Cu, As, Cd, and Pb) after pyrolysis, and their leaching behaviors in different leaching solutions. The results showed that the physicochemical properties and elemental composition of the biochars were basically consistent. However, compared with that of biochars derived from other straws, biochar derived from wheat straw had a higher ash content (22.48%) and H/C radio (0.06). Meanwhile, biochar derived from corn straw had a smaller micropore volume (0.006 cm3·g-1) and a correspondingly smaller specific surface area (110.120 m2·g-1), which was consistent with the SEM image. After pyrolysis, the content of HMs (except Cd) increased by 14.04% to 410.81%, especially that of Cu and As. However, the content of Cd in soybean straw and corn straw decreased by 20.49% and 8.20% after pyrolysis, respectively, due to the low boiling point of Cd. Furthermore, most of the HMs (except Cd and Pb) tended to transform from unstable (acid-soluble/exchangeable and reducible forms) to stable forms (oxidizable and residual forms), implying that pyrolysis facilitated the stabilization of the HMs. The HMs in biochar were not leached or were leached in small amounts in ultra-pure water and buffered salt solutions, as opposed to leaching in relatively larger amounts in acetic acid solution and humic acid solution. Cr and Ni showed low leaching capacity in all leaching solutions. Cu showed relatively high leaching capacity in acetic acid solution, with the leaching amount ranging from 2.601 mg·kg-1 to 4.224 mg·kg-1, and As showed a relatively high leaching capacity in humic acid solution, with the leaching amount ranging from 0.074 mg·kg-1to 0.166 mg·kg-1. After pyrolysis, the environmental quality index (PIi) and the Nemerow pollution index (NPI) values of various HMs increased by different degrees. However, the pollution of single HMs remained at a safe level, and the integrated pollution of biochars was at the level of "clean". Due to the significant increase in potential ecological risk factors (Er) of Ni, Cd, and Pb after pyrolysis, the potential ecological risk index (RI) of biochar derived from the rice straw increased slightly. However, the potential ecological risk indexes of biochars derived from other straws significantly decreased after pyrolysis, owing to the stabilization of HMs.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Cádmio , Substâncias Húmicas , Chumbo , Poluentes do Solo/análise , Metais Pesados/química , Carvão Vegetal/química , Zea mays , Oryza/química , Acetatos
4.
Cancer Med ; 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36545697

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous hematopoietic malignancy originated from leukemia stem cells (LSC). Emerging evidence suggests T-cell immunoglobulin mucin-3(Tim3) as surface marker for LSC. However, the clinical significance and biology of Tim-3 in AML remain to be determined, especially those LSCs. In public AML databases as well as our data, we separated AML patients into Tim-3high and Tim-3low subsets using the X-tile software and evaluated the associations between Tim-3 and overall survival (OS) and disease-free survival (DFS). The Cancer Genome Atlas (TCGA) cohort revealed that high Tim-3 expression in leukemic cells was linked with poor prognosis (DFS: p = 0.018; OS: p = 0.041). Furthermore, multiple regression analysis shows that Tim-3 was an independent factor for the prognosis (HR = 2.26, 95% CI = 1.15-4.44, p = 0.017). Validation cohort of public gene expression omnibus (GEO) confirmed that Tim-3 was a prognostic candidate in AML. Besides, in our internal cohort, we also confirmed that over expression of Tim-3 protein in LSC/LPC made poor prognosis in AML. Additionally, we revealed that the LSC markers AKR1C3, CD34, and MMRN1 were upregulated in the Tim-3high group of TCGA. We found that the upregulated genes in the Tim-3high group were mainly enriched in immune response, cytokine binding and cell adhesion molecules, and JAK-STAT signaling pathway, by gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Collectively, we revealed that, for the first time, upregulation of Tim-3 in LSCs at the level of gene and protein expression is associated with poor prognosis and the important biological feature of Tim-3 of LSC in AML.

5.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500562

RESUMO

Interstitial lung disease associated with rheumatoid arthritis (RA-ILD) can lead to interstitial fibrosis and even lung failure as a complication of rheumatoid arthritis (RA), and there is currently no effective treatment and related basic research. Studies have found that resveratrol (Res) can improve the progression of RA by regulating autophagy, and increasing evidence supports the connection between autophagy and common interstitial lung disease (ILD). We explored changes in autophagy levels in fibrotic lungs in RA-ILD and found that the level of autophagy is enhanced in the early stage but inhibited in the late stage. However, resveratrol treatment improved the level of autophagy and reversed the inhibition of autophagy, and attenuated fibrosis. We created corresponding cell models that exhibited the same phenotypic changes as animal models; under the effect of resveratrol, the level of fibrosis changed accordingly, and the fusion process of lysosomes and autophagosomes in autophagy was liberated from the inhibition state. Resveratrol effects were reversed by the addition of the late autophagy inhibitor chloroquine. These results suggest that resveratrol attenuates pulmonary fibrosis, increases autophagic flux, and modulates the autophagy-lysosome pathway, and particularly it may work by improving the formation of autophagic lysosomes, which may be an effective treatment for induced RA-ILD.


Assuntos
Artrite Reumatoide , Doenças Pulmonares Intersticiais , Fibrose Pulmonar , Animais , Resveratrol/farmacologia , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/complicações , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Fibrose , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/etiologia , Autofagia
6.
Front Plant Sci ; 13: 1020309, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388527

RESUMO

Coptis species are the main source of Rhizoma Coptidis (RC) drugs, which have always been used to treat Alzheimer's disease in the clinical experience of ancient China. However, many species of this genus have been largely underutilized until now. With this fact, this research has been designed to investigate for the first time the anti-acetylcholinesterase (AChE) property of different extracts for RC drugs from four Coptis species (C. chinensis, C. deltoidea, C. teeta and C. omeiensis) and to quantify the main alkaloids. Petroleum ether, ethyl acetate and n-butanol fractions of RC drugs were sequentially collected using an accelerated solvent extraction technique. Spectrum-effect relationship and molecular docking were applied to analyse the relationships between alkaloids and AChE inhibitory activity. The N-butanol extract was proven to be the main active fraction, and C. teeta may be the best source of RC drugs for Alzheimer's disease treatment, with significantly lower IC 20, IC 50 and IC 80 values for AChE inhibition. The UPLC/QqQ-MS quantitative analysis showed that the accumulations of 10 alkaloids in RC drugs from different sources greatly varied. Three data processing methods (Random forest, Boruta and Pearson correlation) comprehensively analysed the spectrum-effect relationship and revealed that columbamine, berberine and palmatine were the most important AChE inhibitors that could be used as quality markers to select RC drugs for Alzheimer's disease treatment. In addition, the dominant compounds were successfully docked against AChE to verify the binding affinity and interactions with the active site. The present study can contribute to the reasonable development and utilization of RC drugs from different sources, especially to provide certain evidence for their application in the treatment of Alzheimer's disease.

7.
Front Microbiol ; 13: 1012957, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439846

RESUMO

The cold-adapted and/or salt-tolerant enzymes from marine microorganisms were confirmed to be meritorious tools to enhance the efficiency of biocatalysis in industrial biotechnology. We purified and characterized a dextranase CeDex from the marine bacterium Cellulosimicrobium sp. THN1. CeDex acted in alkaline pHs (7.5-8.5) and a broad temperature range (10-50°C) with sufficient pH stability and thermostability. Remarkably, CeDex retained approximately 40% of its maximal activities at 4°C and increased its activity to 150% in 4 M NaCl, displaying prominently cold adaptation and salt tolerance. Moreover, CeDex was greatly stimulated by Mg2+, Na+, Ba2+, Ca2+ and Sr2+, and sugarcane juice always contains K+, Ca2+, Mg2+ and Na+, so CeDex will be suitable for removing dextran in the sugar industry. The main hydrolysate of CeDex was isomaltotriose, accompanied by isomaltotetraose, long-chain IOMs, and a small amount of isomaltose. The amino acid sequence of CeDex was identified from the THN1 genomic sequence by Nano LC-MS/MS and classified into the GH49 family. Notably, CeDex could prevent the formation of Streptococcus mutans biofilm and disassemble existing biofilms at 10 U/ml concentration and would have great potential to defeat biofilm-related dental caries.

8.
Biomed Pharmacother ; 157: 114024, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36402030

RESUMO

Although statins are shown to have cardiac pleiotropic effects independent of lowering cholesterol, the underlying mechanism remains unclear. Mitochondrial dysfunction induced by increased fatty acid oxidation (FAO) is the culprit in the development of cardiac hypertrophy and dysfunction. This study was to explore whether the cardiac pleiotropic effects of atorvastatin were associated with FAO regulation, with a specific focus on carnitine palmitoyltransferase 1 (CPT1). High-fat diet (HFD)-fed mice and palmitic acid (PA)-stimulated neonatal rat primary cardiomyocytes (NRCMs) were treated with atorvastatin, with or without FAO modulators, signal transducer and activator of transcription 3 (STAT3) agonist, and inhibitor. Atorvastatin (3 mg/kg) did not reduce serum cholesterol levels in HFD-fed mice but ameliorated mitochondrial dysfunction and cardiac hypertrophy. In vitro, atorvastatin and the FAO inhibitor alleviated PA-induced mitochondrial dysfunction and cardiomyocyte hypertrophy. However, the FAO enhancer eliminated atorvastatin's protective effects. Furthermore, atorvastatin decreased CPT1 and FAO levels and prevented STAT3 phosphorylation and nuclear translocation. STAT3 inhibitor had the same inhibitory effects as atorvastatin on CPT1, FAO levels, and cardiomyocyte hypertrophy, whereas STAT3 agonist disrupted these effects of atorvastatin. Our results demonstrate that atorvastatin decreases myocardial FAO by inactivating the p-STAT3/CPT1 signaling pathway, which improves lipid overload-induced mitochondrial dysfunction and cardiac hypertrophy in a cholesterol-independent manner. This is the first study to explore the cardiac pleiotropic effects of atorvastatin with respect to FAO. However, whether atorvastatin regulates FAO in the cardiac hypertrophy model induced by other variables has not been investigated in this work, and this is expected to be performed in the future.

9.
Reprod Biol ; 22(4): 100702, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36327671

RESUMO

Circular RNA (circRNA) have been shown to exert vital functions in the pathological progressions of ovarian cancer (OC). Herein, this study aimed to investigate the role and mechanisms of circ_0015756 in OC progression. Levels of circ_0015756, microRNA (miR)- 145-5p and phosphoserine aminotransferase 1 (PSAT1) were detected using quantitative real-time polymerase chain reaction, Western blot or immunohistochemistry assays. Cell proliferation, apoptosis, migration and invasion were determined using cell counting kit-8, 5-Ethynyl-2'-Deoxyuridine (Edu) incorporation, flow cytometry, transwell and Western blot assays. The binding interaction between miR-145-5p and circ_0015756 or PSAT1 was confirmed by bioinformatics prediction and dual-luciferase reporter assay. Tumor formation assay in nude mice was performed to determine the tumor growth in vivo. Circ_0015756 was highly expressed in OC tissues and cells. Knockdown of circ_0015756 suppressed cancer cell growth, migration and invasion in vitro, as well as impeded tumor growth in vivo. In a mechanical study, circ_0015756 directly bound to miR-145-5p, and inhibition of miR-145-5p reversed the effects of circ_0015756 knockdown on OC cells. Moreover, miR-145-5p directly targeted PSAT1, and miR-145-5p weakened OC cell growth, migration and invasion via targeting PSAT1. Importantly, further studies confirmed that circ_0015756 could indirectly regulate PSAT1 expression via sponging miR-145-5p. In all, circ_0015756 accelerated OC tumorigenesis through regulating miR-145-5p/PSAT1 axis, providing a new therapeutic target for OC.


Assuntos
MicroRNAs , Neoplasias Ovarianas , RNA Circular , Transaminases , Animais , Feminino , Humanos , Camundongos , Carcinogênese , Proliferação de Células , Camundongos Nus , MicroRNAs/genética , Neoplasias Ovarianas/genética , RNA Circular/genética , Transaminases/genética
10.
Front Genet ; 13: 1024300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313453

RESUMO

DNA methylation is closely related to the occurrence and development of many diseases, but its role in obesity is still unclear. This study aimed to find the potential differentially methylated genes associated with obesity occurrence and development. By combining methylation and transcriptome analysis, we identified the key genes in adipose tissue affecting the occurrence and development of obesity and revealed the possible molecular mechanisms involved in obesity pathogenesis. We first screened 14 methylation-related differential genes and verified their expression in adipose tissue by quantitative polymerase chain reaction (qPCR). Seven genes with the same expression pattern were identified as key genes, namely, CCRL2, GPT, LGALS12, PC, SLC27A2, SLC4A4, and TTC36. Then, the immune microenvironment of adipose tissue was quantified by CIBERSORT, and we found that the content of M0 macrophages and T follicular helper cells in adipose tissue was significantly increased and decreased, respectively, in the obese group. Furthermore, the relationship between key genes and the immune microenvironment was analyzed. Additionally, the metabolic pathway activity of each sample was calculated based on the ssGSEA algorithm, and the key gene-metabolic network was constructed. Moreover, we performed a CMAP analysis based on the differential genes in adipose tissue to screen out drugs potentially effective in obesity treatment. In conclusion, we identified seven methylation-related key genes closely related to obesity pathogenesis and explored the potential mechanism of their role in obesity. This study provided novel insights into the molecular mechanisms and management of obesity.

11.
Front Pharmacol ; 13: 975291, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059990

RESUMO

Glioblastoma (GBM) is the most malignant tumor of the central nervous system in adults. Irradiation (IR) and temozolomide (TMZ) play an extremely important role in the treatment of GBM. However, major impediments to effective treatment are postoperative tumor recurrence and acquired resistance to chemoradiotherapy. Our previous studies confirm that Yin Yang 1 (YY1) is highly expressed in GBM, whereby it is associated with cell dedifferentiation, survival, and therapeutic resistance. Targeted delivery of small interfering RNA (siRNA) without blood-brain barrier (BBB) restriction for eradication of GBM represents a promising approach for therapeutic interventions. In this study, we utilize the engineering technology to generate T7 peptide-decorated exosome (T7-exo). T7 is a peptide specifically binding to the transferrin receptor. T7-exo shows excellent packaging and protection of cholesterol-modified Cy3-siYY1 while quickly releasing payloads in a cytoplasmic reductive environment. The engineered exosomes T7-siYY1-exo could deliver more effciently to GBM cells both in vitro and in vivo. Notably, in vitro experiments demonstrate that T7-siYY1-exo can enhance chemoradiotherapy sensitivity and reverse therapeutic resistance. Moreover, T7-siYY1-exo and TMZ/IR exert synergistic anti-GBM effect and significantly improves the survival time of GBM bearing mice. Our findings indicate that T7-siYY1-exo may be a potential approach to reverse the chemoradiotherapy resistance in GBM.

12.
Molecules ; 27(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36144789

RESUMO

In previous studies, Auriculariaauricula polysaccharides (AAP) has been found to improve type 2 diabetes mellitus, but its mechanism remains unclear. In this study, we sought to demonstrate that AAP achieves remission by altering the gut microbiota in mice with type 2 diabetes. We successfully constructed a type 2 diabetes mellitus (T2DM) model induced by a high-fat diet (HFD) combined with streptozotocin (STZ), following which fasting blood glucose (FBG) levels and oral glucose tolerance test (OTGG) were observed to decrease significantly after 5 weeks of AAP intervention. Furthermore, AAP enhanced the activities of total superoxide dismutase (T-SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and reduced the content of malondialdehyde (MDA) to alleviate the oxidative stress injury. AAP-M (200 mg/kg/d) displayed the best improvement effect. Moreover, 16S rRNA results showed that AAP decreased the abundance of Firmicutes and increased that of Bacteroidetes. The abundance of beneficial genera such as Faecalibaculum, Dubosiella, Alloprevotella, and those belonging to the family Lachnospiraceae was increased due to the intake of AAP. AAP could reduced the abundance of Desulfovibrio, Enterorhabdus, and Helicobacter. In all, these results suggest that AAP can improve the disorders of glucose and lipid metabolism by regulating the structure of the gut microbiota.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Animais , Auricularia , Bacteroidetes/metabolismo , Glicemia , Catalase/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Firmicutes , Glutationa Peroxidase/farmacologia , Malondialdeído/metabolismo , Camundongos , Polissacarídeos/farmacologia , RNA Ribossômico 16S , Estreptozocina/farmacologia , Superóxido Dismutase/metabolismo
14.
Antiviral Res ; 206: 105404, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36049553

RESUMO

Chronic infection by hepatitis B virus (HBV) is associated with high risks of liver fibrosis, cirrhosis and hepatocellular carcinoma. HBV covalently closed circular DNA (cccDNA) in the nucleus of infected hepatocyte serves as transcription template. Neither natural resolution of acute infection nor current treatment options for chronic infection are believed to cause cccDNA clearance. We previously showed that injection of IL-33-expressing plasmid facilitated clearance of intrahepatic HBV DNA in a mouse model of HBV persistence. In this work, HBV-targeting therapeutic effects of IL-33 were further explored. Murine IL-33 delivered by recombinant adeno-associated virus (AAV-mIL-33) induced clearance of both serum HBV markers and intrahepatic HBV DNA in two mouse models of HBV persistence based on replicon plasmid and recombinant cccDNA (rcccDNA) respectively. Clearance was associated with serum ALT elevations and liver infiltrations by CD4+ and CD8+ T cells, indicating IL-33-induced cellular immune responses against HBV-harboring cells. Adoptive transfer of splenocytes from AAV-mIL-33-cured mice was indeed sufficient to engender similar clearance in recipient mice. In vitro, intracellular, instead of extracellular, IL-33 was mainly responsible for repressing viral transcription, protein production and genome replication in Huh7 cells transfected with HBV replicon or rcccDNA. IL-33 was shown to be recruited onto rcccDNA minichromosome accompanied by loss of transcriptional activation epigenetic marks. Finally, transfection of IL-33 into HBV-infected HepG2/NTCP cells resulted in reduced transcription, antigen expression and genome replication, suggesting repression of canonical cccDNA. These data demonstrated diverse inhibitory effects on HBV and HBV-infected cells mediated by IL-33, and suggest IL-33 as an interesting therapeutic candidate.


Assuntos
Hepatite B Crônica , Hepatite B , Interleucina-33 , Animais , Linfócitos T CD8-Positivos/metabolismo , DNA Circular/genética , DNA Viral/genética , DNA Viral/metabolismo , Modelos Animais de Doenças , Hepatite B/imunologia , Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/metabolismo , Interleucina-33/genética , Interleucina-33/uso terapêutico , Camundongos , Replicação Viral/genética
15.
Ann Transl Med ; 10(15): 820, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36034984

RESUMO

Background: Pancreatic cancer (PC) is a highly metastatic and lethal cancer with a very low overall 5-year survival rate. There is an urgent need for identifying new therapeutic agents for this deadly disease. Cardiac glycosides (CGs) have been traditionally used for their potent cardiovascular activities and have also recently been reported to exhibit anti-tumor effects. Proscillaridin A (Pro A), a natural CG, has been shown to display anti-tumor effects on multiple cancer types. Methods: The cytotoxic effect of Pro A on PC cells was determined using cell viability assay, colony formation assay and transwell assay in vitro. Cell apoptosis, cell cycle, reactive oxygen species (ROS) generation, intracellular Ca2+ levels and mitochondrial membrane potential (MMP) were assayed by flow cytometry. Panc-1-xenografted mice model was used to evaluate Pro A's effect in tumor growth. Mitochondria morphology was observed by transmission electron microscopy. LC3 aggregation was assessed by GFP-LC3 fluorescence microscopy. Gene expression was assayed by western blot or real-time quantitative polymerase chain reaction (qPCR). Results: Pro A inhibits the proliferation, migration and invasion of Panc-1, BxPC-3 and AsPC-1 PC cells in vitro, and Panc-1 cells display the highest sensitivity with an IC50 at the nano-molar level. In vivo, Pro A treatment inhibits tumor progression in Panc-1 xenograft nude mice. Pro A treatment promotes both cell apoptosis and autophagy, and Pro A-treated PC cells display characteristics of mitochondrial damage including increased ROS generation, intracellular Ca2+ levels and disruption of MMP. In addition, high sensitivity towards Pro A of Panc-1 cells compared to BxPC-3 and AsPC-1 cells could be partially attributed to the loss of endogenous SMAD4 expression in the latter. Conclusions: Our findings suggest that Pro A constitutes a promising therapeutic candidate for certain types of PC.

16.
J Mol Model ; 28(9): 264, 2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-35986785

RESUMO

The dispersion of silica dioxide (SiO2)/sodium lauryl sulfate (SDS) has been widely used in hydrocarbon reservoirs, but its instability is still a problem in practical engineering applications. The dispersion morphology of SiO2 nanoparticles before and after modification was studied by TEM, and the thermal stability of different foam dispersions was evaluated by FoamScan. In this paper, the mechanism of foam stability was investigated by combining the measurement of interfacial energy of nanoparticles at the gas-liquid interface with dynamics simulation of molecular diffusion. The results showed that SiO2/SDS dispersions had good thermal stability due to the synergistic effect of SiO2 nanoparticles and SDS. The addition of SiO2 nanoparticles improved the interfacial energy and interfacial activity at the gas-liquid interface, meanwhile limited the movement of SDS molecules and water molecules, which was beneficial for foam stability. Notably, the addition of modified SiO2 nanoparticles further enhanced the interfacial energy at the gas-liquid interface and strengthened the restriction of water/SDS molecular movement, thereby slowing down the drainage and decay of the foam dispersions. The mechanism investigation of SiO2/SDS dispersions was of benefit to foam flooding in hydrocarbon reservoirs.

18.
Comput Intell Neurosci ; 2022: 3464984, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814559

RESUMO

To solve the problems existing in the research of scene recognition, this paper studies a new convolutional neural network target detection model to achieve a better balance between the accuracy and speed of high-speed scene image recognition. First, aiming at the problem that the image is easy to be disturbed by impurities and poor quality in fine-grained image recognition, a preprocessing method based on the Canny edge detection is designed and the Canny operator is introduced to process the gray image. Second, the L2 regularization algorithm is used to optimize the basic network framework of the convolutional neural network, enhance the stability of the model in a complex environment, improve the generalization ability of the model, and improve the recognition accuracy of the algorithm to a certain extent. Finally, by collecting the campus environment datasets under different environmental conditions, the location recognition experiment and heat map visualization experiment are carried out. Experiments show that compared with the basic convolution neural network algorithm, the algorithm has better recognition performance and good generalization ability. The research of this study realizes the effective combination of multiframe convolution neural network and batch normalization algorithm and has a good practical effect on scene image recognition.


Assuntos
Algoritmos , Redes Neurais de Computação
19.
Front Psychol ; 13: 875266, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783747

RESUMO

With increased global competition and the advent of the knowledge economy, developing graduate students' ability to innovate in their research has become a core focus of graduate education. Graduate students' perceived help and assistance from supervisors is one of the key resources for research innovation. This study explored the relationships between graduate students' perceived supervisor support and their innovative behavior in research, and examined the mediation effect of creative self-efficacy, their confidence in abilities to generate creative ideas or produce creative outcomes. Survey data were collected from a sample of 996 Chinese graduate students. The results revealed that academic support was negatively related to idea generation and idea search; personal support was positively related to overcoming obstacles; autonomy support was positively related to all factors of innovative behavior except overcoming obstacles and innovation outputs. The mediation analysis suggested that creative self-efficacy significantly mediated the relationship between academic support and graduate students' innovative behavior in research. The results of this study highlight the significance of both supervisor support and creative self-efficacy in developing graduate students' research innovation. The findings have significant implications for stimulating students' research innovation and for improving the quality of graduate education.

20.
Environ Sci Technol ; 56(15): 10691-10698, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35833964

RESUMO

This study is the first to investigate the emission and environmental fate of one type of modified methylsiloxane with double-bond (vinyl) groups. During 2018-2020, 2,4,6-trimethyl-2,4,6-trivinylcyclotrisiloxane (V3), 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (V4), and 2,4,6,8,10-pentavinyl-2,4,6,8,10-pentamethylcyclopentasiloxane (V5) were found in aqueous (

Assuntos
Poluentes do Solo , Purificação da Água , Biossólidos , Cloreto de Polivinila , Esgotos , Solo/química , Poluentes do Solo/metabolismo
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