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1.
Artigo em Inglês | MEDLINE | ID: mdl-38662912

RESUMO

The conventional von Neumann architecture has proven to be inadequate in keeping up with the rapid progress in artificial intelligence. Memristors have become the favored devices for simulating synaptic behavior and enabling neuromorphic computations to address challenges. An artificial synapse utilizing the perovskite structure PbHfO3 (PHO) has been created to tackle these concerns. By employing the sol-gel technique, a ferroelectric film composed of Au/PHO/FTO was created on FTO/glass for the purpose of this endeavor. The artificial synapse is composed of Au/PHO/FTO and exhibits learning and memory characteristics that are similar to those observed in biological neurons. The recognition accuracy for both MNIST and Fashion-MNIST data sets saw an increase, reaching 92.93% and 76.75%, respectively. This enhancement resulted from employing a convolutional neural network architecture and implementing an improved stochastic adaptive algorithm. The presented findings showcase a viable approach to achieve neuromorphic computation by employing artificial synapses fabricated with PHO.

2.
Nat Prod Res ; 35(7): 1172-1179, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31328555

RESUMO

One new oleanane-type nortriterpene, rosanortriterpene A (1), and one new ursane-type nortriterpene, rosanortriterpene B (2), were isolated from the fruits of Rosa laevigata var. leiocapus. The structures of 1-2 were fully characterised on the basis of extensive spectroscopic analysis, including IR, HRESIMS, as well as 1D and 2D NMR spectral data (HSQC, 1H-1H COSY, and HMBC). To the best of our knowledge, this represents the first study on the chemical constituents of R. laevigata var. leiocapus. Compounds 1-2 exhibited moderate inhibitory effects on NO production in LPS stimulated RAW264.7 cells with IC50 values of 29.29 ± 3.64 and 14.28 ± 1.20 µM, respectively.


Assuntos
Frutas/química , Rosa/química , Triterpenos/isolamento & purificação , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Concentração Inibidora 50 , Camundongos , Testes de Sensibilidade Microbiana , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácido Oleanólico/farmacologia , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Triterpenos/química , Triterpenos/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-32595744

RESUMO

Radiation enteritis is a common side effect of radiotherapy for abdominal and pelvic malignancies, which can lead to a decrease in patients' tolerance to radiotherapy and the quality of life. It has been demonstrated that glycyrrhizin (GL) possesses significant anti-inflammatory activity. However, little is known about its anti-inflammatory effect in radiation enteritis. In the present study, we aimed to investigate the potential anti-inflammatory effects of GL on radiation enteritis and elucidate the possible underlying molecular mechanisms involved. The C57BL/6 mice were subjected to 6.5 Gy abdominal X-ray irradiation to establish a model of radiation enteritis. Hematoxylin and eosin staining was performed to analyze the pathological changes in the jejunum. The expression of TNF-α in the jejunum was analyzed by immunochemistry. The levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1ß, and HMGB1 in the serum were determined by enzyme-linked immunosorbent assay. The intestinal absorption capacity was tested using the D-xylose absorption assay. The levels of HMGB1 and TLR4 were analyzed by western blotting and immunofluorescence staining. We found that GL significantly alleviated the intestinal damage and reduced the levels of inflammatory cytokines, such as TNF-α, IL-6, IL-1ß, and HMGB1 levels. Furthermore, the HMGB1/TLR4 signaling pathway was significantly downregulated by GL treatment. In conclusion, these findings indicate that GL has a protective effect against radiation enteritis through the inhibition of the intestinal damage and the inflammatory responses, as well as the HMGB1/TLR4 signaling pathway. Thereby, GL might be a potential therapeutic agent for the treatment of radiation enteritis.

4.
J Asian Nat Prod Res ; 20(10): 962-968, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28891321

RESUMO

Two new ent-kaurane diterpenes (1-2), together with five known analogs, were isolated from the stems of Eurya chinensis. The structures of new compounds were established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 3 exhibited noticeable anti-inflammatory activity as denoted by inhibiting LPS-induced nitric oxide (NO) production in RAW264.7 cells with an IC50 value of 7.82 µM. Compound 4 showed potent cytotoxic activity against human cancer cell lines NCI-H46, HepG2 and SW480 with IC50 values ranging from 7.45 to 8.54 µM.


Assuntos
Diterpenos do Tipo Caurano/isolamento & purificação , Theaceae/química , Animais , Linhagem Celular Tumoral , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Caules de Planta/química , Células RAW 264.7
5.
J Asian Nat Prod Res ; 20(9): 837-843, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28868919

RESUMO

Three new dimeric kavalactones, designated as diyangonins A-C (1-3), along with two known analogs were isolated from the roots of Piper methysticum. Their structures were elucidated by means of extensive analysis of their 1D, 2D NMR, and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units in head-to-tail or head-to-head mode. Compounds 1-5 were evaluated for their cytotoxic activities against human tumor cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Kava/química , Lactonas/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lactonas/química , Lactonas/farmacologia , Espectroscopia de Ressonância Magnética , Raízes de Plantas/química
6.
Nat Prod Res ; 32(2): 182-188, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28641459

RESUMO

One new ent-kaurane diterpene derivative (1), along with four known diterpenes, was isolated from the stems of Eurya chinensis R.Br. The structure of the new compound was established by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. Compound 1 showed moderate anti-inflammatory activities with IC50 value of 8.12 µM. This is the first example of diterpenoids with 4-hydroxy-4-(2-hydroxyethyl)-1-hydroxyl-cyclohexanoyl substituent.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Diterpenos do Tipo Caurano/isolamento & purificação , Caules de Planta/química , Plantas Medicinais/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Estrutura Molecular , Análise Espectral
7.
Nat Prod Res ; 31(21): 2459-2466, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28391729

RESUMO

Three new kavalactone dimers, designated as yangonindimers A-C (1-3), along with one known analogue were isolated from the roots of Piper methysticum. Their structures were elucidated via extensive analysis of their 1D, 2D NMR and mass spectroscopic data. All these dimers possess a skeleton featuring a cyclobutane ring connecting two kavalactone units. Compounds 1-4 were evaluated for their cytotoxic activities against human tumour cell lines NCI-H46, SW480 and HepG2, but none showed significant activity.


Assuntos
Ciclobutanos/isolamento & purificação , Kava/química , Lactonas/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ciclobutanos/química , Ciclobutanos/farmacologia , Dimerização , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Lactonas/química , Lactonas/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Raízes de Plantas/química
8.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(11): 1541-1545, 2016 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-27881347

RESUMO

OBJECTIVE: To observe the effect of rhynchophylline on methamphetamine-dependent zebrafish and explore the possible mechanism. METHODS: Zebrafish were divided into control group, amphetamine group, low- (50 mg/kg) and high (100 mg/kg)-dose rhynchophylline groups, and ketamine (150 mg/kg) group. Conditioned place preference (CPP) was induced in zebrafish with methamphetamine, and the staying time in the drug box and the tracking map of the zebrafish were observed with Noldus Ethovision XT system. The protein expressions of TH, NR2B and GLUR2 in the brain of zebrafish with CPP were detected with Western blotting. RESULTS: Compared with the control group, zebrafish in methamphetamine group showed significant variations in the staying time and swimming distance in the drug box after conditioning (P<0.05) with obvious alterations of NR2B, TH and GLUR2 expressions in the brain (P<0.05). Treatment of methamphetamine-dependent zebrafish with high-dose rhynchophylline significantly reduced the variations in the staying time and swimming distance in the drug box (P<0.05) and in the expressions of NR2B, TH and GLUR2 in the brain (P<0.05). CONCLUSION: Rhynchophylline can inhibit methamphetamine dependence in zebrafish, the mechanism of which may involve the expressions of TH, NR2B and GLUR2 proteins in the brain.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Metanfetamina/farmacologia , Peixe-Zebra/fisiologia , Animais , Ketamina/farmacologia , Oxindóis , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
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