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1.
Chem Commun (Camb) ; 57(15): 1907-1910, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33491686

RESUMO

In this work, we presented a solid-state hybrid electrolyte dielectric film fabricated by a facile solution process, composed of ionic liquid and high-k polymers for leakage current reduction. With ions involved in the dielectric, the organic transistor can be operated under low voltage, and some essential synaptic behaviors were successfully simulated by the electrostatic coupling effect for building neuromorphic computing systems.

3.
Tree Physiol ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33440426

RESUMO

Apomixis is a form of reproduction that does not involve the fertilization of female gametes by male gametes but instead involves the production of offspring directly from the female parent. The offspring of apomixis are genetically identical to the female parent and inherit its traits. Therefore, apomixis has great potential for application to agricultural genetic breeding. However, it remains unclear whether apomictic species require pollination, and the impacts of pollination on such species are poorly understood. We investigated the effects of pollination on the apomictic species Zanthoxylum bungeanum by analyzing its fertilization process, assembling its transcriptome, and measuring hormone concentrations, fruit setting rate, and gene expression levels. Transcriptome sequencing of pollinated and unpollinated fruits resulted in a total of 69,131 PacBio reads. Of these, 7,102 genes were upregulated, and 6,491 genes were downregulated. Analysis of the differentially expressed genes (DEGs) and construction of a weighted gene co-expression network showed that many DEGs were involved in plant hormone signal transduction, suggesting that hormonal signaling during development differs between pollinated and unpollinated fruit. The germination rate of Z. bungeanum pollen in vitro was only 11%, and pollen could not germinate in the embryo sac to complete fertilization. Although pollination did not enable Z. bungeanum to complete the sexual reproduction process, it significantly increased abscisic acid (ABA) concentration and fruit setting rate. Spraying 100 µg/L ABA also significantly increased the fruit setting rate. Therefore, ABA appears to be a key factor in the regulation of fruit setting in apomictic Z. bungeanum. Based on these results, we suggest that some male plants be cultivated in Z. bungeanum plantations or exogenous ABA be sprayed to increase the likelihood of pollination and thereby increase the fruit setting rate.

4.
Nano Lett ; 21(1): 389-396, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33337160

RESUMO

In parallel to the burgeoning field of soft electronics, soft plasmonics focuses on the design and fabrication of plasmonic structures supported on elastomers and to understand how their properties respond to mechanical deformations. Here, we report on a partial ligand-stripping strategy to fabricate elastomer-supported gold nanobipyramid (NBP) plasmene nanosheets. Unlike spherelike building blocks, NBP-building blocks display complex orientation-dependent plasmonic responses to external strains. By collecting polarized plasmonic resonance spectra in conjunction with electrostatic eigenmode modeling, we reveal simultaneous changes in interparticle spacing and spatial orientations of NBP building blocks under mechanical strains. Such changes are directly related to initial NBP packing orders. Further analysis of strain sensitivities for various NBP plasmenes indicated that plasmonic spectra of ∼45° oriented samples are mostly susceptible to strain at acute polarized angles. The results presented may enable novel applications in future soft optoelectronic devices in sensing, encryption, and data storage.

5.
J Agric Food Chem ; 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33300333

RESUMO

The purplish-red color of "Tailihong" jujube fruit skins is caused primarily by anthocyanin accumulation, but the mechanisms that underlie anthocyanin biosynthesis in jujube fruit have rarely been studied. We performed metabolomic and transcriptomic analyses of jujube fruit skins at different developmental stages and identified a total of 158 flavonoids, among which cyanidin-3-O-rutinoside and peonidin-3,5-O-diglucoside were the primary anthocyanins. During fruit development and maturation, the anthocyanin content was strongly correlated with the expression of ZjANS and ZjUGT79B1, suggesting that these are key genes in the anthocyanin biosynthesis process. Transcriptomic analysis indicated that the transcription factors ZjMYB5, ZjTT8, and ZjWDR3 regulated anthocyanin biosynthesis in jujube fruit skins. Subcellular localization experiments confirmed that ZjANS and ZjUGT79B1 were localized to the nucleus and the endoplasmic reticulum. ZjMYB5 and ZjTT8 were found only in the nucleus, whereas strong fluorescence signals from ZjWDR3 were observed in the nucleus and cytoplasm. Prokaryotic expression and in vitro enzyme activity assays showed that the recombinant ZjANS protein catalyzed the formation of cyanidin from (+)-catechin. Secondary glycosylation by ZjUFGT79B1 modified cyanidin-3-O-glucoside to produce cyanidin-3-O-rutinoside, and ZjCCoAOMT readily catalyzed the production of the methylated anthocyanin peonidin-3,5-O-diglucoside from cyanidin 3,5-O-glucoside. Dual-Luciferase and GUS activity assays showed that the ZjANS and ZjUGT79B1 promoters were activated by ZjMYB5, ZjTT8, and ZjWDR3. All data indicated that these three transcription factors played important roles in anthocyanin biosynthesis in the color mutant Ziziphus jujuba cv. Tailihong, contributing to anthocyanin accumulation by enhancing the expression of ZjANS and ZjUGT79B1.

7.
Chem Biodivers ; 17(12): e2000813, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33155408

RESUMO

Paeonia veitchii has been widely distributed in China under different ecological types. Its roots contain diverse phytochemical constituents, which possess very high bioactivities. However, the influence of ecological factors on activities and ingredients of P. veitchii roots still remains unknown. The purpose of this research was to analyze the variation in bioactivities and phytochemical composition of P. veitchii roots upon exposure to various ecological factors. Seven P. veitchii populations collected from different regions in China were evaluated. The results of correlation analysis suggested that four major ecological factors, including average annual temperature, elevation, total potassium, and organic matter, had a strong correlation with the bioactivities of P. veitchii roots. Further, the major ecological factors were also highly correlated with the contents of naringin, gallic acid, benzoylpaeoniflorin, and paeoniflorin. The principal component analysis results supported four major metabolites as the main contributing ingredients. All populations were classified into three groups, G1, G2, and G3, through hierarchical cluster analysis. G1 showed more significant advantages in the above-mentioned four ecological factors, four active ingredients, and bioactivities compared to the other two groups. P. veitchii roots growing at lower average annual temperature, high elevation, rich total potassium and organic matter in the soils were presumed to have relatively higher bioactivities. These data expand the study on the bioactivities and phytochemical composition of P. veitchii roots and have a guiding significance for the ecological factor selection during the cultivation process of this herbaceous peony species.

8.
Nanoscale Horiz ; 5(11): 1515-1523, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33103698

RESUMO

Skin-like optoelectronic sensors can have a wide range of technical applications ranging from wearable/implantable biodiagnostics, human-machine interfaces, and soft robotics to artificial intelligence. The previous focus has been on electrical signal transduction, whether resistive, capacitive, or piezoelectric. Here, we report on "optical skin" strain sensors based on elastomer-supported, highly ordered, and closely packed plasmonic nanocrystal arrays (plasmene). Using gold nanocubes (AuNCs) as a model system, we find that the types of polymeric ligands, interparticle spacing, and AuNC sizes play vital roles in strain-induced plasmonic responses. In particular, brush-forming polystyrene (PS) is a "good" ligand for forming elastic plasmenes which display strain-induced blue shift of high-energy plasmonic peaks with high reversibility upon strain release. Further experimental and simulation studies reveal the transition from isotropic uniform plasmon coupling at a non-strained state to anisotropic plasmon coupling at strained states, due to the AuNC alignment perpendicular to the straining direction. The two-term plasmonic ruler model may predict the primary high-energy peak location. Using the relative shift of the averaged high-energy peak to the coupling peak before straining, a plasmene nanosheet may be used as a strain sensor with the sensitivity depending on its internal structures, such as the constituent AuNC size or inter-particle spacing.

9.
Neurotherapeutics ; 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32959271

RESUMO

The molecular mechanism of Alzheimer-like cognitive impairment induced by manganese (Mn) exposure has not yet been fully clarified, and there are currently no effective interventions to treat neurodegenerative lesions related to manganism. Protein phosphatase 2 A (PP2A) is a major tau phosphatase and was recently identified as a potential therapeutic target molecule for neurodegenerative diseases; its activity is directed by the methylation status of the catalytic C subunit. Methionine is an essential amino acid, and its downstream metabolite S-adenosylmethionine (SAM) participates in transmethylation pathways as a methyl donor. In this study, the neurotoxic mechanism of Mn and the protective effect of methionine were evaluated in Mn-exposed cell and rat models. We show that Mn-induced neurotoxicity is characterized by PP2Ac demethylation accompanied by abnormally decreased LCMT-1 and increased PME-1, which are associated with tau hyperphosphorylation and spatial learning and memory deficits, and that the poor availability of SAM in the hippocampus is likely to determine the loss of PP2Ac methylation. Importantly, maintenance of local SAM levels through continuous supplementation with exogenous methionine, or through specific inhibition of PP2Ac demethylation by ABL127 administration in vitro, can effectively prevent tau hyperphosphorylation to reduce cellular oxidative stress, apoptosis, damage to cell viability, and rat memory deficits in cell or animal Mn exposure models. In conclusion, our data suggest that SAM and PP2Ac methylation may be novel targets for the treatment of Mn poisoning and neurotoxic mechanism-related tauopathies.

10.
iScience ; 23(7): 101281, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32622263

RESUMO

Bacterial infections caused by pathogens have always been a thorny issue that threatens human health, and there is urgent need to develop a new generation of antimicrobial nano-agents and treatments. Herein, biodegradable nickel disulfide (ND) nanozymes as excellent antibacterial agents that integrate excellent photothermal performance, nano-catalysis property, and glutathione (GSH)-depleting function have been successfully constructed. The ND nanozymes can effectively catalyze the decomposition of H2O2 to produce ⋅OH, and the hyperthermia of ND nanozymes generated by photothermal therapy (PTT) can further increase its catalytic activity, which provides rapid and effective bacterial killing effect compared with nano-catalytic treatment or PTT alone. Surprisingly, the ND nanozymes have the ability of GSH consumption, thus enhancing its sterilization effect. Moreover, the ND nanozymes are biodegradable nanomaterials that do not cause any significant toxicity in vivo. Collectively, the ND nanozymes with excellent photothermal performance, catalytic activity, and GSH-depleting function are used for high-efficiency sterilization.

11.
J Cancer ; 11(15): 4542-4549, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32489471

RESUMO

Background: Although the prostate-specific antigen (PSA) testing was widely used for early detection of prostate cancer (PCa), it is difficult for PSA to distinguish the PCa from benign prostatic hyperplasia (BPH) patients. Emerging evidence has shown that microRNA (miRNA) was a promising biomarker for PCa screening. Methods: We applied miRNA profiling from microarray or high-throughput sequencing in Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases to identify the differentially expressed miRNAs in PCa patients (n = 1,017) and controls (n = 413). Then, qRT-PCR analysis was used to validate the expression of candidate miRNAs in our independent cohort, include 66 PCa cases and 63 BPH patients diagnosed by biopsy. The area under the receiver operating characteristic curve (AUC) was conducted to evaluate the diagnostic efficacy of miRNAs and PSA. Results: In the microarray analysis, we identified two consistently differently expressed miRNAs (miR-103a-3p and let-7f-5p) between PCa patients and controls. In the subsequent qRT-PCR analysis, the let-7f-5p was upregulated in PCa compared with BPH patients (P=2.17E-07), but no statistically difference of miR-103a-3p expression was observed (P=0.456). The AUC was 0.904 for combination of lef-7f-5p and PSA, which was significantly higher than that of let-7f-5p (0.782) or PSA (0.795) alone (P=7.55E-04 and P=2.09E-03, respectively). Besides, the results of decision curve analysis and nomogram prediction indicated that combination of let-7f-5p and PSA had superior predictive accuracy of PCa. Conclusions: Our study suggests that plasma let-7f-5p combining PSA could serve as potentially diagnostic biomarkers for PCa.

12.
Technol Health Care ; 28(S1): 245-251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32364157

RESUMO

BACKGROUND: Absence epilepsy (AE) is a systemic disease of the brain, which mainly occurs during childhood and adolescence. The control mechanism is still unclear, and few theoretical studies have been conducted to investigate this. OBJECTIVE: In this paper, we employed external direct voltage stimulation in the subthalamic nucleus to explore mechanisms that inhibit absence seizures. METHODS: All simulation results are obtained by the four-order Runge-Kutta method in the MATLAB environment. The inhibition mechanism can be inferred from the results. RESULTS: We found that the seizures may be inhibited by tuning the strength of the voltage to suitable ranges. This regulation may be achieved through the competition between the inhibitory projections from the basal ganglia to the thalamus. CONCLUSION: Because the mechanism underlying the treatment of epilepsy with a uniform direct current electric field is unclear, we hope that these results can inspire further experimental studies.

13.
J Colloid Interface Sci ; 575: 24-34, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32344216

RESUMO

Nanotechnology's rapid development of nanostructured materials with disruptive material properties has inspired research for their use as electrocatalysts to potentially substitute enzymes. Herein, a novel electrocatalytic nanomaterial was constructed by growing gold nanograss (AuNG) on 2D nanoassemblies of gold nanocubes (AuNC). The resulting structure (NG@NC) was used for the detection of H2O2via its electrochemical reduction. The NG@NC electrode displayed a large active surface area, resulting in improved electron transfer efficiency. On the nanoscale, AuNG maintained its structure, providing high stability and reproducibility of the sensing platform. Our nanostructured electrode showed excellent catalytic activity towards H2O2 at an applied potential of -0.5 V vs Ag/AgCl. This facilitated H2O2 detection with excellent selectivity in an environment like human urine, and a linear response from 50 µM to 30 mM, with a sensitivity of 100.66 ± 4.0 µA mM-1 cm-2. The NG@NC-based sensor hence shows great potential in nonenzymatic electrochemical sensing.

14.
Neuropsychiatr Dis Treat ; 16: 829-836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273709

RESUMO

Objective: To explore the effect of Type 2 diabetes mellitus (T2DM) on the development of neuropsychiatric symptoms (NPS) in early Alzheimer's disease (AD). Methods: From September 2017 to March 2019, a cross-sectional study was conducted on the clinical data of 158 early AD patients over 65 years old in the Department of Neurology of Daping Hospital. All early stage of AD patients were divided into early stage of AD with NPS group and early stage of AD without NPS group according to the presence or absence of NPS. Clinical data of age, sex, body mass index (BMI), smoking and alcohol consumption, history of hypertension, hyperlipidemia, white matter leisure (WML) and T2DM, MMSE, CDR and NPI-Q scores were collected. Multivariate logistic regression analyses were performed to examine the relationship between T2DM and NPS in early AD. Results: Compared with the early stage of AD group without NPS, the early stage of AD group with NPS was older, the proportion of women was higher, the proportion of T2DM, hypertension, hyperlipidemia and WML was higher, and the MMSE score was lower (P< 0.05). T2DM was an independent risk factor for NPS in early stage of AD patients (OR 3.48, 95% CI 2.91-3.84). The incidence of T2DM in AD patients with depression, anxiety, nighttime behavioral disturbances, and appetite disturbances was significantly higher than in AD patients without these symptoms. T2DM was an independent risk factor of depression (OR 2.04, 95% CI 1.71-2.38), anxiety (OR 1.69, 95% CI 1.38-1.97), nighttime behavioral disturbances (OR 1.95, 95% CI 1.75-2.13) and appetite disturbances (OR 1.62, 95% CI 1.33-1.94) in early AD patients. Conclusion: T2DM was an important independent risk factor for NPS in early AD, which promotes the occurrence of depression, anxiety, nighttime behavioral disturbances and appetite disturbances in early AD.

15.
Cogn Neurodyn ; 14(1): 137-154, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32015772

RESUMO

Absence epileptiform activities are traditionally considered to be primarily induced by abnormal interactions between the cortical and thalamic neurons, which form the thalamocortical circuit in the brain. The basal ganglia, as an organizational unit in the brain, has close input and output relationships with the thalamocortical circuit. Although several studies report that the basal ganglia may participate in controlling and regulating absence epileptiform activities, to date, there have been no studies regarding whether the basal ganglia directly cause absence epileptiform activities. In this paper, we built a basal ganglia-corticothalamic network model to determine the role of basal ganglia in this disease. We determined that absence epileptiform activities might be directly induced by abnormal coupling strengths on certain pivotal pathways in the basal ganglia. These epileptiform activities can be well controlled by the coupling strengths of three major pathways that project from the thalamocortical network to the basal ganglia. The results implied that the substantia nigra pars compacta (SNc) can be considered to be the effective treatment target area for inhibiting epileptiform activities, which supports the observations of previous studies. Particularly, as a major contribution of this paper, we determined that the final presentation position of the epileptic slow spike waves is not limited to the cerebral cortex; these waves may additionally appear in the thalamus, striatal medium spiny neurons, striatal fast spiking interneuron, the SNc, subthalamic nucleus, substantia nigra pars reticulata and globus pallidus pars externa. In addition, consistent with several previous studies, the delay in the network was observed to be a critical factor for inducing transitions between different types of absence epileptiform activities. Our new model not only explains the onset and control mechanism but also provides a unified framework to study similar problems in neuron systems.

16.
Nat Commun ; 11(1): 946, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075976

RESUMO

Amides are among the most fundamental functional groups and essential structural units, widely used in chemistry, biochemistry and material science. Amide synthesis and transformations is a topic of continuous interest in organic chemistry. However, direct catalytic asymmetric activation of amide C-N bonds still remains a long-standing challenge due to high stability of amide linkages. Herein, we describe an organocatalytic asymmetric amide C-N bonds cleavage of N-sulfonyl biaryl lactams under mild conditions, developing a general and practical method for atroposelective construction of axially chiral biaryl amino acids. A structurally diverse set of axially chiral biaryl amino acids are obtained in high yields with excellent enantioselectivities. Moreover, a variety of axially chiral unsymmetrical biaryl organocatalysts are efficiently constructed from the resulting axially chiral biaryl amino acids by our present strategy, and show competitive outcomes in asymmetric reactions.


Assuntos
Amidas/química , Aminoácidos/química , Aminoácidos/síntese química , Técnicas de Química Sintética/métodos , Catálise , Lactamas/química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
17.
Small ; 16(13): e1907472, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32068955

RESUMO

Synaptic electronics is a new technology for developing functional electronic devices that can mimic the structure and functions of biological counterparts. It has broad application prospects in wearable computing chips, human-machine interfaces, and neuron prostheses. These types of applications require synaptic devices with ultralow energy consumption as the effective energy supply for wearable electronics, which is still very difficult. Here, artificial synapse emulation is demonstrated by solid-ion gated organic field-effect transistors (OFETs) with a 3D-interface conducting channel for ultralow-power synaptic simulation. The basic features of the artificial synapse, excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), and high-pass filtering, are successfully realized. Furthermore, the single-fiber based artificial synapse can be operated by an ultralow presynaptic spike down to -0.5 mV with an ultralow reading voltage at -0.1 mV due to the large contact surface between the ionic electrolyte and fiber-like semiconducting channel. Therefore, the ultralow energy consumption at one spike of the artificial synapse can be realized as low as ≈3.9 fJ, which provides great potential in a low-power integrated synaptic circuit.

18.
Chemistry ; 26(15): 3252-3258, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-31950547

RESUMO

Pyrido-benzodiazepine derivatives are undoubtedly one of the most important structural motifs in the marketed drugs and the drug candidates. Commonly synthetic methods for construction of the benzodiazepine ring derivatives are based on the condensation reactions of two highly functionalized synthons. The development of synthesis for these compounds, however, is hampered by the regioselectivity and atom economy. In this work, a one-step synthesis of pyrido-benzodiazepine backbones and its analogues is achieved through continuous ring-opening hydrolysis of benzimidazole salts and intramolecular C-H bond activation. The reaction mechanism is explored by control experiments and density functional theory (DFT) calculations.

19.
J Mater Chem B ; 8(16): 3655-3660, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-31998927

RESUMO

Sweat pH is a key health indicator related to metabolism and homeostasis level through hydrogen ion concentration in biological bio-fluid. Therefore, increasing research efforts have been directed to develop wearable pH sensors towards continuous non-invasive monitoring of sweat pH values in the out-of-hospital environments. Herein, we report a stretchable gold fiber-based electrochemical pH sensor based on our recently developed elastomer-bonded gold nanowire coating technology. The densely packed gold film offers superior strain-insensitive conductivity, high stretchability and large electrochemical active surface area (EASA). By electrodepositing polyamine (PANI) and Ag/AgCl onto the gold fibers, we could selectively detect the pH based on open circuit potentials in an ion-selective electrode design. The obtained fiber-based pH sensors feature a great sensitivity (60.6 mV per pH), high selectivity against cationic interference and high stretchability (up to 100% strain). One of the attributes for the fiber-based sensors is that they can be weaved into textiles, holding great potential for integration into everyday clothing for "unfeelable" personal health monitoring.

20.
Cancer Gene Ther ; 27(9): 726-738, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31636361

RESUMO

Tumorigenesis and metastasis depend on intricate interactions between genetically altered tumor cells and their surrounding microenvironment. It is, however, unclear regarding the molecular mechanisms underlying the progress and metastasis of human clear-cell renal cell carcinoma in the microenvironment with fibroblasts. In this work, we investigated the effect of normal fibroblasts on the metastasis of renal cancer and the relevant signaling pathways. We isolated normal fibroblasts from normal renal tissues and used normal fibroblast-conditioned medium culture renal cancer cells. The CCK-8 and transwell assays showed that normal fibroblasts conditioned medium significantly enhanced ccRCC cell migration. IL6 mediated the cross talk between normal fibroblasts and the cancer cells, and promoted tumor cell migration through the STAT3 pathway. In contrast, GATA3 was downregulated at both mRNA and protein levels in the normal fibroblast-conditioned medium treated with renal cancer cells, but upregulated in adjacent normal tissues. GATA3 overexpression significantly reduced STAT3 phosphorylation and attenuated the migration in both renal cancer cell and IL6-stimulated renal cancer cell. Taken together, our findings suggest that the IL6/STAT3 pathway plays a crucial role in the normal fibroblast-enhanced clear-cell renal cell carcinoma metastasis, while GATA3 may mitigate this effect by inhibiting IL6/STAT3 signaling.

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