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1.
Mater Sci Eng C Mater Biol Appl ; 106: 110159, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753404

RESUMO

Stimuli-triggered drug delivery systems have been recognized as a crucial strategy to achieve on-demand drug release at the tumor for improving therapeutic efficacy. In this work, novel biocompatible and biodegradable reactive oxygen species (ROS)-responsive amino acid- based polymeric micelles were developed for tumor-specific drug release triggered by high ROS levels in cancer cells, which were composed of amphiphilic poly(aspartic acid) (PASP) derivatives (PASP-BSer) with phenylborate serine (BSer) side groups as the ROS-responsive unit. A series of PASP-BSer conjugates with different degree of substitution (DS) were synthesized, and their self-assembly and H2O2-responsive behaviors were investigated to optimize the structure of PASP-BSer. In vitro drug loading and release studies confirmed that the optimized PASP-BSer micelles could effectively encapsulate the model anticancer drug doxorubicin (Dox) and exhibit desirable H2O2-triggered release behaviors. More importantly, Dox-loaded PASP-BSer micelles showed high selective cytotoxicity against A549 cancer cells than L929 normal cells. Accordingly, PASP-BSer micelles have significant potential as on-demand drug carriers for anticancer therapy.

2.
Cancer Cell ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31786140

RESUMO

Long non-coding RNAs (lncRNAs) are critical for regulating HOX genes, aberration of which is a dominant mechanism for leukemic transformation. How HOX gene-associated lncRNAs regulate hematopoietic stem cell (HSC) function and contribute to leukemogenesis remains elusive. We found that HOTTIP is aberrantly activated in acute myeloid leukemia (AML) to alter HOXA-driven topologically associated domain (TAD) and gene expression. HOTTIP loss attenuates leukemogenesis of transplanted mice, while reactivation of HOTTIP restores leukemic TADs, transcription, and leukemogenesis in the CTCF-boundary-attenuated AML cells. Hottip aberration in mice abnormally promotes HSC self-renewal leading to AML-like disease by altering the homeotic/hematopoietic gene-associated chromatin signature and transcription program. Hottip aberration acts as an oncogenic event to perturb HSC function by reprogramming leukemic-associated chromatin and gene transcription.

3.
J Chromatogr A ; : 460740, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31796250

RESUMO

The identification and quantification of post-translational modifications (PTMs) is a crucial step required during the development of therapeutic proteins. In particular, the characterization of charge variants separated by cation exchange chromatography (CEX) is a tedious process commonly performed with an off-line manual fraction collection followed by peptide mapping. To improve the efficiency of this time-consuming approach, a generic on-line multi-dimensional LC/MS approach was developed for the characterization of various monoclonal antibody (mAb) isotypes and a bi-specific antibody (BsAb). Fractions collected from 1D CEX analysis were consecutively reduced on a 2D reversed phase liquid chromatography (RPLC) column (polyphenyl), digested within 1-2 min using a 3D immobilized trypsin cartridge, and finally the obtained peptides were separated on another 4D RPLC column (C18), and simultaneously identified with a Q Exactive™ mass spectrometer. 2D RPLC columns and 3D trypsin cartridges from different suppliers were compared, as well as the effects of reducing agents. The effect of 2D and 4D RPLC column temperature, and 2D RPLC column mass load were also systematically studied. Under optimal conditions, the multi-dimensional LC/MS system described in this paper is a robust tool for the on-line digestion of proteins and shows high repeatability. Similar levels of oxidation and deamidation were measured using the off-line and on-line approaches for the same stressed samples. The lower amounts of deamidation and isomerization measured at some asparagine and aspartic acid residues by the on-line approach compared to the manual off-line procedure suggest reduced artifacts using the on-line methodology. The multi-dimensional LC/MS described here enables fast, on-line, automated characterization of therapeutic antibodies without the need for off-line fraction collection and sample pre-treatment (manual approach). The entire workflow can be completed within less than one day, compared to weeks with the manual off-line procedure.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31796710

RESUMO

 Many ocular diseases (such as glaucoma, diabetic retinopathy, age-related macular degeneration, and traumatic eye injuries) can result in the degeneration of retinal cells and the subsequent loss of vision. Some kinds of treatments, such as drugs, stem cell transplantation and surgery are reported to be effective in certain patients. However, no confirmatively effective, convenient and low-price intervention has been available so far. Physical exercise has been reported to exert neuroprotective effects on several neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. Studies investigating the potential impacts of exercise on retinal diseases are rapidly emerging. Here we review these up-to-date findings from both human and animal studies, and discuss the possible mechanisms underlying exercise-elicited protection on retina.

5.
J Dairy Sci ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31733844

RESUMO

This study investigated the antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) isolated from cases of subclinical bovine mastitis in China, as well as resistance mechanisms and virulence genes encoding adhesins and toxins. We determined antimicrobial susceptibility using the disk diffusion method, and analyzed resistance, adhesin, and toxin genes using PCR. We confirmed MRSA in 73 of 498 (14.7%) Staph. aureus isolates recovered from subclinical mastitic milk samples. All isolates were positive for mecA. The MRSA isolates showed high resistance to penicillin (100.0%), gentamicin (100.0%), and tetracycline (98.6%). All MRSA isolates harbored resistance genes blaZ (penicillin), aacA/aphD (gentamicin), and tetM (alone or in combination with tetK, tetracycline). Moreover, all isolates carried the adhesin genes fnbpA, clfA, clfB, cna, sdrE, and map/eap, and most carried sdrC (98.6%), sdrD (95.9%), bbp (94.5%), and ebpS (80.8%). The toxin genes seh, hla, and hld were present in all isolates, and most isolates carried sea (71.2%), seg (84.9%), sei (82.2%), lukE-lukD (97.3%), and hlg (72.6%). These findings of high-level resistance to antimicrobials commonly used in dairy cattle should lead to calls for antibiogram analysis before antimicrobial therapy. The high frequency of adhesin and toxin genes in MRSA indicates their potential virulence in bovine mastitis in China.

6.
Andrologia ; : e13386, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733069

RESUMO

The miRNAs are dysregulated in BPH. Rape bee pollen (RBP) is used to improve benign prostatic hyperplasia (BPH). Whether RBP treats BPH by regulating the dysregulated miRNAs remains unclear. Here, we identified miRNAs regulated along with the improvement of BPH by RBP in posterior lobes of prostate in rats. Firstly, to screened miRNAs might relate to improvement of BPH by RBP, we compared differentially expressed miRNAs between BPH model group and RBP group by high-throughput sequencing. As a result, 10 known miRNAs and 17 novel miRNA were up-regulated in RBP group, and 6 known and 13 novel miRNAs were down-regulated. Secondly, among the known miRNAs, we identified those that might relate to BPH by RT-qPCR, while only rno-miR-184 was screened, so we compared it among normal control group, BPH model group and RBP group. The results showed that rno-miR-184 was significantly lower expressed in BPH group, but up-regulated along with the improvement of BPH by RBP. Moreover, expression level of rno-miR-184 was no difference between RBP group and normal control level. Therefore, we considered that RBP might improve BPH through regulating expression of miRNAs like rno-miR-184 in prostate in rats.

8.
EMBO Mol Med ; : e10835, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31709724

RESUMO

Aerobic glycolysis is a hallmark of metabolic reprogramming in tumor progression. However, the mechanisms regulating glycolytic gene expression remain elusive in neuroblastoma (NB), the most common extracranial malignancy in childhood. Herein, we identify that CUT-like homeobox 1 (CUX1) and CUX1-generated circular RNA (circ-CUX1) contribute to aerobic glycolysis and NB progression. Mechanistically, p110 CUX1, a transcription factor generated by proteolytic processing of p200 CUX1, promotes the expression of enolase 1, glucose-6-phosphate isomerase, and phosphoglycerate kinase 1, while circ-CUX1 binds to EWS RNA-binding protein 1 (EWSR1) to facilitate its interaction with MYC-associated zinc finger protein (MAZ), resulting in transactivation of MAZ and transcriptional alteration of CUX1 and other genes associated with tumor progression. Administration of an inhibitory peptide blocking circ-CUX1-EWSR1 interaction or lentivirus mediating circ-CUX1 knockdown suppresses aerobic glycolysis, growth, and aggressiveness of NB cells. In clinical NB cases, CUX1 is an independent prognostic factor for unfavorable outcome, and patients with high circ-CUX1 expression have lower survival probability. These results indicate circ-CUX1/EWSR1/MAZ axis as a therapeutic target for aerobic glycolysis and NB progression.

9.
J Clin Lipidol ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31767518

RESUMO

BACKGROUND: Familial hypercholesterolemia is characterized by high levels of low-density lipoprotein cholesterol (LDL-C), and causes of familial hypercholesterolemia include apolipoprotein B (APOB) loss-of-function mutations (LOFm) and proprotein convertase subtilisin/kexin type 9 (PCSK9) gain-of-function mutations (GOFm). OBJECTIVE: The aim of this study was to compare the pharmacokinetics and pharmacodynamics of alirocumab between patients with APOB LOFm vs PCSK9 GOFm. METHODS: Patients (6 APOB LOFm and 17 PCSK9 GOFm carriers) with LDL-C ≥70 mg/dL on maximally tolerated lipid-lowering therapies received alirocumab 150 mg at Weeks 0, 2, 4, and 6, placebo at Week 8, alirocumab at Week 10, placebo at Weeks 12 and 14, then completed a follow-up period at Week 22. RESULTS: At Week 8, mean ± standard error (SE) alirocumab concentration was lower in APOB LOFm carriers compared with PCSK9 GOFm carriers (12.12 ± 1.81 vs 16.74 ± 2.53 mg/L). APOB LOFm carriers had higher mean ± SE total PCSK9 (6.56 ± 0.73 mg/L) and lower mean ± SE free PCSK9 (0.025 ± 0.016 mg/L) at Week 8 compared with PCSK9 GOFm carriers (4.21 ± 0.35 and 0.11 ± 0.035 mg/L for total and free PCSK9, respectively). Despite this observed greater PCSK9 suppression, mean ± SE percent LDL-C reduction was lower in APOB LOFm (55.3 ± 1.0%) compared with PCSK9 GOFm carriers (73.1 ± 0.9%). Treatment-emergent adverse events occurred in 16 patients (94.1%) in the PCSK9 GOFm group and 5 patients (83.3%) in the APOB LOFm group. CONCLUSIONS: Overall, PCSK9 inhibition with alirocumab results in clinically meaningful reductions in LDL-C in both APOB LOFm and PCSK9 GOFm carriers, although reductions were greater in the PCSK9 GOFm carriers. The results indicate a possible underlying contributor to hypercholesterolemia other than PCSK9 in patients with APOB LOFm. CLINICAL TRIAL REGISTRATION: NCT01604824; clinicaltrials.gov.

10.
J Recept Signal Transduct Res ; : 1-5, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774019

RESUMO

Although ecotropic viral integration site 2 A (EVI2A) plays key roles in several cancers, the expression and function of EVI2A in osteosarcoma (OS) have not been investigated. Hence, we explored the expression of EVI2A and its clinical significance of EVI2A of OS. Firstly, we investigated the expression of EVI2A in OS tissues. The relationship of EVI2A expression and survival time was analyzed using Kaplan-Meier plotter. Then, we used quantitative reverse transcription PCR (qRT-PCR) to confirm the expression level of EVI2A in OS cell lines. Cell proliferation, and wound-healing experiments were used to identify the biological function of EVI2A. Moreover, EVI2A-mediated MEK/ERK signaling pathway was evaluated using western blotting. Data suggested that EVI2A was highly expressed in OS tissues, and high-expression of EVI2A was associated with worse overall survival in OS patients. Moreover, the up-regulation of it was observed in OS cell lines (Saos2, and MG63). Knockdown of EVI2A suppressed cell proliferation and migration of OS. Western blotting revealed that the inactivation of MEK/ERK pathway was found in OS cells after EVI2A knockdown. Our data implicated the crucial role of EVI2A in the progression of OS, demonstrating that expression of EVI2A may offer an attractive novel prognostic signature for OS.

11.
J Med Chem ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31693353

RESUMO

It is a great challenge to design drugs that penetrate the blood-brain barrier to inhibit brain tumor growth by acting against multiple targets and also improve their delivery efficacy and targeting ability to cancer cells. To overcome the above problems, we designed a multitarget metal agent for treating brain tumors based on an human serum albumin (HSA)-cell penetrating peptide conjugate. Thus, we rationally screened copper (Cu) and 2-acetyl-3-ethylpyrazine thiosemicarbazones to synthesize six compounds, and we investigated their structure-activity relationships and confirmed multiple mechanisms for brain glioma cells. The HSA-6b complex structure indicated that 6b binds to the IIA subdomain of HSA and His242 replaces the Br ligand in 6b in coordination with Cu2+. In vivo data suggested that both 6b and the HSA-6b-peptide conjugate penetrate the blood-brain barrier and inhibit brain tumor growth with few side effects. Furthermore, the HSA-peptide conjugate also improved the delivery efficacy and targeting ability of 6b in vivo.

12.
Mol Cancer ; 18(1): 158, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718709

RESUMO

BACKGROUND: Circular RNAs (circRNAs), a subclass of non-coding RNAs, play essential roles in tumorigenesis and aggressiveness. Our previous study has identified that circAGO2 drives gastric cancer progression through activating human antigen R (HuR), a protein stabilizing AU-rich element-containing mRNAs. However, the functions and underlying mechanisms of circRNAs derived from HuR in gastric cancer progression remain elusive. METHODS: CircRNAs derived from HuR were detected by real-time quantitative RT-PCR and validated by Sanger sequencing. Biotin-labeled RNA pull-down, mass spectrometry, RNA immunoprecipitation, RNA electrophoretic mobility shift, and in vitro binding assays were applied to identify proteins interacting with circRNA. Gene expression regulation was observed by chromatin immunoprecipitation, dual-luciferase assay, real-time quantitative RT-PCR, and western blot assays. Gain- and loss-of-function studies were performed to observe the impacts of circRNA and its protein partner on the growth, invasion, and metastasis of gastric cancer cells in vitro and in vivo. RESULTS: Circ-HuR (hsa_circ_0049027) was predominantly detected in the nucleus, and was down-regulated in gastric cancer tissues and cell lines. Ectopic expression of circ-HuR suppressed the growth, invasion, and metastasis of gastric cancer cells in vitro and in vivo. Mechanistically, circ-HuR interacted with CCHC-type zinc finger nucleic acid binding protein (CNBP), and subsequently restrained its binding to HuR promoter, resulting in down-regulation of HuR and repression of tumor progression. CONCLUSIONS: Circ-HuR serves as a tumor suppressor to inhibit CNBP-facilitated HuR expression and gastric cancer progression, indicating a potential therapeutic target for gastric cancer.

13.
Aquat Toxicol ; 217: 105331, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31683207

RESUMO

Ocean acidification and marine biofouling, which may interact in the future, pose two major threats to global coastal ecosystems. Yet, the fate of highly invasive fouling species in a rapidly acidifying ocean remains poorly understood, due to lack of information on multigenerational consequences at different levels of biological organization. Here, we investigated antioxidant responses of the mussel, Musculista senhousia, a swiftly spreading invasive fouling species in global coastal waters, following transgenerational exposure to elevated pCO2. In the face of seawater acidification, M. senhousia without a prior history of transgenerational exposure to elevated pCO2 showed resistance to lipid peroxidation, but significantly increased activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), indicated oxidative stress responses. However, enhanced transgenerational immunity occurred, as exemplified by observations that mussels originating from parents exposed to elevated pCO2 exhibited significantly lower activities of SOD, CAT and GPx in comparison to those spawn from parents exposed to ambient pCO2. Rapid transgenerational acclimation of M. senhousia in terms of reduced oxidative stress responses can likely be linked to the enhanced capacity of maintaining acid-base homeostasis previously demonstrated. These findings provide the first evidence of transgenerational plasticity at the biochemical level in highly invasive fouling bivalve species, and represent a step forward in understanding how they respond and acclimate in an acidifying ocean.

14.
Food Chem ; : 125823, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31757489

RESUMO

Phenolic acids, which are important aromatic secondary metabolites, are widely distributed in plant foods. In this study, a simple, economical and fast on-line immobilized trypsin microreactor was developed for evaluating the inhibitory activity of phenolic acids by capillary electrophoresis. The Michaelis-Menten constant (Km) of immobilized trypsin was determined as 0.99 mM, and the half-maximal inhibitory concentration (IC50) and inhibition constant (Ki) of benzamidine were measured as 3.39 and 1.68 mM, respectively. Then, the developed strategy was applied to investigate the inhibitory activity of six phenolic acids on trypsin. The results showed that gallic acid, caffeic acid and ferulic acid had high inhibitory activity at concentration of 150 µM. Molecular docking results illustrated that gallic acid, caffeic acid and ferulic acid can interact indirectly with the catalytic and substrate-binding sites of trypsin. The developed strategy is an effective tool for evaluating inhibitory activity of phenolic acids on trypsin.

15.
Plant Biol (Stuttg) ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31758615

RESUMO

Ethylene(ET), known as a key phytohormone associated with plant-pathogen interaction, plays critical roles in plants' resistance in biotic stress. Brassinosteroids (BRs) also play essential roles in biotic stress. Plant immunity is regulated by a huge phytohormone regulation network. However, the relationship between BR and ET in plant immunity is unclear. To investigate the relationship between ET and BR in plant defenses against Pst DC3000 in Nicotiana benthamiana, we used chemical treatments, genetic approaches and inoculation experiments. Foliar applications of ET and BR enhanced plant resistance to Pst DC3000 inoculation, while treatment of brassinazole (BRZ, a specific BR biosynthesis inhibitor) eliminated the ET induced plant resistance to Pst DC3000. Silencing of DWARF 4 (DWF4, a key BR biosynthetic gene), BRASSINOSTEROID INSENSITIVE 1 (BRI1, BR receptor) and BRASSINOSTEROID-SIGNALING KINASE 1 (BSK1, the downstream of BRI1) also neutralized the ET-induced plant resistance to DC3000. ET can induce callose deposite and reactive oxygen species (ROS) accumulation to resist DC3000, inhibition of BR biosynthesis and blocking of BR signaling transduction completely eliminated it. Thus, our results suggest that the involvement of ET in plant resistance possibly by the induction of callose deposite and ROS accumulation in a BR-dependent way.

16.
Artigo em Inglês | MEDLINE | ID: mdl-31771181

RESUMO

Oxygen deficiency and coldness are the main challenges for highway tunnel construction in high-altitude areas such as western Sichuan plateau. The artificial oxygen supply and anti-freezing structure in the tunnel construction process has a significant impact on vocational health and the environment. Thus, the conditions of tunnels need to be carefully evaluated before construction. However, the current design code for tunnel construction contains few instructions about these aspects. This paper attempts to establish a simple evaluation method to guide the construction design by analyzing the oxygen partial pressure of trachea, the mean temperature of the coldest month, and the maximum freezing depth for tunnel projects in western Sichuan plateau. Based on the on-site meteorological monitoring at different altitudes of three typical tunnels in the western Sichuan plateau and the comparative analysis of the existing meteorological data, the corresponding relationships between the three parameters and the altitude were investigated. The thresholds by altitude for grading the tunnels are identified as 2100 m and 4200 m, respectively. The highway tunnels in the western Sichuan plateau are graded in three categories, namely, general-altitude tunnels, high-altitude tunnels, and ultra-high-altitude tunnels. The corresponding measures of oxygen supply and freezing prevention for different graded tunnels are recommended. The results would provide a basis for the design and construction of new tunnels and enhance the service life and operations safety of the tunnels in western Sichuan plateau and other similar high-altitude areas.

17.
J Sep Sci ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31701660

RESUMO

Xanthii Fructus is extensively used as an herbal medicine. Ingestion of this herb is associated with severe hepatotoxicity and nephrotoxicity. Atractyloside and carboxyatractyloside are two dominative toxic constituents in Xanthii Fructus. However, their pharmacokinetic study is lacking. In this study, a novel high-performance liquid chromatography-tandem mass spectrometry method was developed to simultaneously quantify the rat plasma concentrations of atractyloside and carboxyatractyloside. After protein precipitation, the analytes were chromatographic separated on a ZORBAX Eclipse Plus column (2.1 × 150 mm id, 5 µm) under gradient elute. In the negative electrospray ionization mode, the transitions at m/z 725.3→645.4 for atractyloside, m/z 769.3→689.4 for carboxyatractyloside, and m/z 479.2→121.1 for paeoniflorin (the internal standard) were acquired by multiple reaction monitoring. This analytical method showed good linearity over 1-500 ng/mL for atractyloside and 2-500 ng/mL for carboxyatractyloside with acceptable precision and accuracy. No matrix effect, instability and carryover occurred in the analysis procedure. The extraction recoveries were greater than 85.0%. This method was applied to a preliminary pharmacokinetic study by orally administering Xanthii Fructus extract (9 g/kg) to rats, which was useful to evaluate the role of these two compounds in Xanthii Fructus-induced toxicity.

18.
Planta ; 251(1): 22, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31781953

RESUMO

MAIN CONCLUSION: This study unravels the transcriptional response of a highly productive faba bean cultivar under vernalization treatment. Faba bean (Vicia faba L.) is a member of the Leguminosae family and an important food crop worldwide providing valuable nutrients for humans. However, genome-wide studies and comprehensive sequencing resources of faba bean remain limited. Vernalization is crucial for enhanced yields in a number of winter-sown crops. However, the effects of vernalization on faba bean remain unknown. In this study, we generated a high-quality transcriptome assembly and functional annotation source for vernalized faba bean (Vicia faba L.) cv. Tongxian-2, a domesticated cultivar from southern China. A total of 369.9 million clean Illumina paired-end RNA-Seq reads were generated, and the transcriptome was assembled into 68,683 unigene sequences, with an average length of 1018 bp and an N50 of 1652 bp. Comprehensive functional annotation provided putative functional descriptions for more than 70% of the faba bean transcripts. We annotated a total of 1560 faba bean transcripts encoding transcription factors (TFs) belonging to 55 distinct TF families. The bHLH (168 transcripts), ERF (123 transcripts) and WRKY (105 transcripts) contained the largest number of TFs in response to vernalization. Genome-wide transcript changes comparing vernalized and unvernalized seedlings were investigated using bioinformatics approaches, which revealed a strong repression of photosynthesis and carbon metabolism, while genes participating in 'response to stress' were significantly induced. We also specifically identified vernalization-induced twenty-two 'pollen-pistil interaction' genes. A detailed functional annotation and expression profile analyses unveiled a number of protein kinases, which were specifically induced in vernalized seedlings. We also identified a total of 6852 simple sequence repeats (SSRs) in 6552 transcripts, representing a valuable genomic molecular marker resource for faba bean. In summary, this study provides new insights into the vernalization process in this economically valuable crop. The transcriptome data obtained provides us with a valuable candidate gene resource for future functional and molecular breeding studies. These data will contribute to the genome annotation for ensuing genome projects.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31746187

RESUMO

The oxygen (O2)-dependent resistance change of multilayered molybdenum ditelluride (MoTe2) channels was characterized. A variation of the channel resistance could reproducibly determine relative O2 content (denoted as the O2 index). We found that Joule heating in a layered MoTe2 field-effect transistor caused the O2 index to decrease drastically from 100 to 12.1% in back gate modulation. Furthermore, Joule heating caused effective O2 desorption from the MoTe2 surface and repeatable O2 detection by multilayered MoTe2 channels was realized. This work not only explored the influence of O2 on the electrical properties of multilayered MoTe2 channels but also revealed that MoTe2 channels are promising for sensing O2 in an environmental condition.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31679778

RESUMO

Capacitive devices have drawn a beautiful application scene in electronic device systems ranging from touch sensors, energy storages and multifunction transistors, but serving as memristive term is still blank. Sweet potato peel (SPP) as function layer was employed to develop the memristive device with Ag/SPP/F-doped SnO2 (FTO) structure. A current-voltage (I-V) hysteresis, which is characterized by a typical capacitive behavior, is impressively observed in the developed device. Nonvolatile data storage is feasible using the non-zero-crossing I-V hysteresis because the resistance states can be well maintained. Charge transfer at the Ag/SPP and SPP/FTO interfaces, and the interplay between Ag+ ions and charges are responsible for this non-zero-crossing I-V hysteresis behaviors. This work possibly gives an insight into the data storage in terms of a new conception electronic device based on environment-friendly material.

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