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1.
Adv Mater ; 35(20): e2211600, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36841244

RESUMO

Organic field-effect transistors (OFETs) based on 2D monolayer organic semiconductors (OSC) have demonstrated promising potentials for various applications, such as light emitting diode (LED) display drivers, logic circuits, and wearable electrocardiography (ECG) sensors. To date, the fabrications of this class of highly crystallized 2D organic semiconductors (OSC) are dominated by solution shearing. As these organic active layers are only a few molecular layers thick, their compatibilities with conventional thermal evaporated top electrodes or sophisticated photolithography patterning are very limited, which also restricts their device density. Here, an electrode transfer stamp and a semiconductor patterning stamp are developed to fabricate OFETs with channel lengths down to 3 µm over a large area without using any chemicals or causing any damage to the active layer. 2D 2,9-didecyldinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10 -DNTT) monolayer OFETs developed by this new approach shows decent performance properties with a low threshold voltage (VTH ) less than 0.5 V, intrinsic mobility higher than 10 cm2 V-1 s-1 and a subthreshold swing (SS) less than 100 mV dec-1 . The proposed patterning approach is completely comparable with ultraflexible parylene substrate less than 2 µm thick. By further reducing the channel length down to 2 µm and using the monolayer OFET in an AC/DC rectifying circuit, the measured cutoff frequency is up to 17.3 MHz with an input voltage of 4 V. The newly proposed electrode transfer and patterning stamps have addressed the long-lasting compatibility problem of depositing electrodes onto 2D organic monolayer and the semiconductor patterning. It opens a new path to reduce the fabrication cost and simplify the manufacturing process of high-density OFETs for more advanced electronic or biomedical applications.

2.
J Asian Nat Prod Res ; 25(9): 890-898, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36448552

RESUMO

A new oleanane-type triterpenoid saponin, 21ß, 22α-di-O-angeloyl-15α, 16α, 28-trihydroxyolean-12-ene 3ß-O-α-L-rhamnopyranosyl-(1→3)-α-D-xylopyranosyl-(1→3)-ß-D-glucopyranoside (1), together with five known compounds (2-5), were isolated from Camellia nitidissima. Their structures were elucidated based on spectroscopic methods, including extensive NMR and MS spectra. Compound 1 showed potential inhibitory activity on α-glucosidase with the IC50 values of 185.9 ± 44.5 µmol/L.


Assuntos
Camellia , Saponinas , Triterpenos , Saponinas/farmacologia , Saponinas/química , alfa-Glucosidases , Triterpenos/química , Camellia/química , Estrutura Molecular
3.
Mitochondrial DNA B Resour ; 8(11): 1248-1252, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188431

RESUMO

Semiothisa cinerearia Bremer & Grey, 1853 belongs to the lepidopteran family Geometridae, subfamily Ennominae. We sequenced the complete mitochondrial genome of S. cinerearia by PCR and Sanger sequencing method. The mitochondrial genome of S. cinerearia is 15,523 bp in length and contains a typical set of 37 genes with 'MIQ' type gene arrangement and a 394 bp AT-rich regions. Except for cox1 using CGA as initiation codon, all protein-coding genes (PCGs) start with ATN codons and except for nad2 and nad4l using TAG as termination codon, all PCGs terminated with TAA codon. A phylogenetic tree including 39 genus of subfamily Ennominae was first reconstructed based on the mitochondrial genome sequences with nucleotide substitution model GTR + G + I, which showed that the genera Amraica, Jankowskia, and Ectropis are not monophyletic and S. cinerearia and Macaria notata are classified together.

4.
Dev Comp Immunol ; 132: 104406, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35364136

RESUMO

In innate immunity, autophagy is an important molecular mechanism that plays a critical role in the animal defense system. Given the importance of anti-microbial autophagy in the innate immune processes, the relationship between anti-microbial autophagy and LPS-induced innate immunity in A. pernyi was investigated. Quantitative RT-PCR analysis revealed that autophagy-related genes (ATG6, ATG5, and ATG12) were induced following LPS injection. LPS treatment in the Relish knockdown larvae reduced the expression of autophagy-related genes, especially ATG5. Furthermore, ATG5 depletion decreased the innate immune effect, while its over-expression with ATG12 was induced after the LPS challenge. The dual-luciferase assay revealed that Relish could regulate ATG5 expression by binding directly to the promoter of the ATG5 gene. Overall, our findings show that Relish regulates the ATG5 transcription to eliminate Gram-negative bacteria by anti-microbial autophagy, implying a strong connection between autophagy and innate immunity in immunologic homeostasis.


Assuntos
Lipopolissacarídeos , Mariposas , Animais , Autofagia/fisiologia , Proteína 12 Relacionada à Autofagia/genética , Proteína 12 Relacionada à Autofagia/metabolismo , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Imunidade Inata
5.
ACS Appl Mater Interfaces ; 12(49): 54991-54999, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33236878

RESUMO

Piezoelectric materials enable emerging self-powered wearable and implantable devices. The sol-gel technology with the lowest cost for large-scale production has shown its potential for producing high-quality PZT thin films. However, fabricating PZT films with a sufficient thickness for different application scenarios requires a long and repeated coating and heat-treatment process. The traditional solution-based method usually requires at least 20 coating cycles to fabricate 2 µm-thick PZT thin films. To save cost and improve fabrication efficiency, we develop a simplified thin-film fabrication method assisted by PZT powder. The new method can fabricate 2 µm-thick PZT films in a single step, one spin coating and annealing. Experiments indicate that the powder-based PZT thin films have porous structures and outstanding piezoelectric performances. The measured d33 of the powder-based PZT thin film is 47 pm/V. Both solution-based and powder-based PZT thin films show high flexibility and good fatigue resistance. Furthermore, we explore 2D mica as the substrate and achieve the transfer-free fabrication of flexible PZT thin-film nanogenerators that effectively simplify the complicated physical or chemical thin-film lift-off processes. The nanogenerator prototypes demonstrate the capability of accurately monitoring dynamic responses of flexible and soft human tissues.

6.
RSC Adv ; 8(10): 5071-5078, 2018 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35542447

RESUMO

The glycosyltransferase OleD variant as a catalyst for the glycosylation of four pairs of epimers of cardiotonic steroids (CTS) are assessed. The results of this study demonstrated that the OleD-catalyze glycosylation of CTS is significantly influenced by the configuration at C-3 and the A/B fusion mode. 3ß-OH and A/B ring cis fusion are favoured by OleD (ASP). An epoxide ring at C-14 and C-15 further increases the bioconversion rate; while an acetyl group at C-16 and lactone ring type at C-17 did not influence the biotransformation. A high conversion rate corresponded to a low K m value. A molecular docking simulation showed that filling of hydrophobic pocket II and interaction with residue Tyr115 may play an important role in the glycosylation reactions catalyzed by OleD glycosyltransferases. Furthermore, the glycosylation products showed a stronger inhibitory activity for Na+, K+-ATPase than the corresponding aglycones. This study provides the first stereoselective properties for OleD (ASP) catalyzed glycosylation.

7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 42(1): 8-12, 2017 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-28216491

RESUMO

OBJECTIVE: To explore the correlation between the -31T/C polymorphisms of IL-1ß gene and thesusceptibility of Kawasaki disease (KD).
 Methods: The polymorphism at -31C/T site of IL-1ß gene was genotyped with the method of polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 100 KD patients (KD group) and 100 healthy children (control group). The differences in genotype distribution and allele frequency between the KD group and the control group were analyzed by χ2 test.
 Results: There were significant differences in genotype and allele frequencies for IL-1ß gene polymorphism at -31C/T site between the KD group and the control group (all P<0.05). The risk of KD in the KD group with TT genotype was 0.37 times as that with the CT and CC genotypes (χ2=5.65, P<0.005, OR=0.37, 95%CI 0.16 to 0.85). But there was no significant difference in genotype and allele frequencies for IL-1ß genepolymorphism at -31 site between the KD group with coronary artery lesion and the KD group without coronary artery lesion(all P>0.05).
 Conclusion: The polymorphism at -31T/C site of IL-1ß gene is associated with genetic susceptibility of KD. The KD patients with TT genotype are at low risk.


Assuntos
Interleucina-1beta/genética , Síndrome de Linfonodos Mucocutâneos/genética , Polimorfismo Genético/fisiologia , Criança , Doença da Artéria Coronariana/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase
8.
J Sep Sci ; 39(7): 1278-85, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26864462

RESUMO

This study presents an efficient strategy for separation of three phenolic compounds with high molecular weight from the crude extract of Terminalia chebula Retz. by ultrasound-assisted extraction and high-speed counter-current chromatography. The ultrasound-assisted extraction conditions were optimized by response surface methodology and the results showed the target compounds could be well enriched under the optimized extraction conditions. Then the crude extract was directly separated by high-speed counter-current chromatography without any pretreatment using n-hexane/ethyl acetate/methanol/water (1:7:0.5:3, v/v/v/v) as the solvent system. In 180 min, 13 mg of A, 18 mg of B, and 9 mg of C were obtained from 200 mg of crude sample. Their structures were identified as Chebulagic acid (A, 954 Da), Chebulinic acid (B, 956 Da), and Ellagic acid (C) by (1) H NMR spectroscopy.


Assuntos
Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Terminalia/química , Distribuição Contracorrente , Peso Molecular , Ultrassom
9.
J Sep Sci ; 37(24): 3760-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25283274

RESUMO

Barley seedlings are rich in flavones that can have positive effects on people with antihypoxia and antifatigue. Lutonarin and saponarin are two major flavonoid glycosides that have unique structures in barley seedlings. This study presents a new approach for the preparation of lutonarin and saponarin from barely seedlings by membrane separation technology and preparative high-performance liquid chromatography. Preparative conditions of these two flavonoid glycosides by membrane separation technology were studied using response surface methodology. Under the optimized conditions, the total contents of these two flavonoid glycosides amounts to 17.0%.


Assuntos
Apigenina/síntese química , Apigenina/isolamento & purificação , Flavonoides/isolamento & purificação , Glucosídeos/síntese química , Glucosídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Hordeum/química , Plântula/química , Apigenina/química , Cromatografia Líquida de Alta Pressão , Flavonoides/síntese química , Flavonoides/química , Glucosídeos/química , Glicosídeos/síntese química , Glicosídeos/química , Estrutura Molecular
10.
Artigo em Inglês | MEDLINE | ID: mdl-24662143

RESUMO

In this paper, an efficient method was successfully established by the combination of macroporous resin (MR) and high-speed counter-current chromatography (HSCCC) for rapid enrichment and separation of aloe-emodin 8-O-ß-D-glucoside, emodin 1-O-ß-D-glucoside, emodin 8-O-ß-D-glucoside and piceatannol 4'-O-ß-D-(6″-O-gallate)-glucoside. Six kinds of macroporous resins were investigated in the first step and X-5 macroporous resin was selected for the enrichment of the target compounds. The recoveries of the target compounds reached 89.0, 85.9, 82.3 and 84.9% respectively after 40% ethanol elution. In the second step, the target compounds were separated by HSCCC with a two-phase solvent system composed of chloroform/ethyl acetate/methanol/water (8:1:6:5, v/v). The established method will be helpful for further characterization and utilization of Rheum tanguticum. The results demonstrate that MR coupled with HSCCC is a powerful technique for separation of bioactive compounds from natural products.


Assuntos
Antraquinonas/isolamento & purificação , Distribuição Contracorrente/métodos , Glicosídeos/isolamento & purificação , Rheum/química , Estilbenos/isolamento & purificação , Antraquinonas/análise , Antraquinonas/química , Glicosídeos/análise , Glicosídeos/química , Reagentes de Laboratório , Extratos Vegetais/química , Raízes de Plantas/química , Porosidade , Estilbenos/análise , Estilbenos/química
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