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1.
Sensors (Basel) ; 18(2)2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29461506

RESUMO

We investigate the temperature effect on sensing characteristics and drift effect of an arrayed flexible ruthenium dioxide (RuO2)/graphene oxide (GO) chloride sensor at different solution temperatures between 10 °C and 50 °C. The average sensor sensitivities according to our experimental results were 28.2 ± 1.4 mV/pCl (10 °C), 42.5 ± 2.0 mV/pCl (20 °C), 47.1 ± 1.8 mV/pCl (30 °C), 54.1 ± 2.01 mV/pCl (40 °C) and 46.6 ± 2.1 mV/pCl (50 °C). We found the drift effects of an arrayed flexible RuO2/GO chloride sensor in a 1 M NaCl solution to be between 8.2 mV/h and 2.5 mV/h with solution temperatures from 10 °C to 50 °C.

2.
Zhongguo Zhong Yao Za Zhi ; 42(17): 3379-3384, 2017 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-29192450

RESUMO

The constituents from 95% ethanol extract of the roots of Stelleropsis tianschanica were purified by column chromatography techniques, leading to the isolation of 17 compounds. Their structures were elucidated by spectroscopic dataas 5'-methoxy lariciresinol(1), pinoresinol(2), daphnoretin(3), acutissimalignan B(4),(+)-secoisolariciresinol(5),(+)-epipinoresinol(6), 7-methyi-daphnoretin(7), thero-8S-7-methoxysyringylglycerol(8), 1-O-methyl-guaiacylglycerol(9), 2R-22'-ferulic acid ester-2,3-dihydroxypropyl ester(10), vesiculosin(11), 4ß,5ßH-guai-9,7(11)-dien-12,8-olide-1α,8α-diol(12),(-)-nortrachelogenin(13), 4α,5ßH-guai-9,7(11)-dien-12,8-olide-1α,8α-diol(14), matairesinol(15), lariciresinol(16)and isolariciresinol(17). Among them, compounds 1-13 wereobtained for the first time fromthe genus Stelleropsis. Compounds 3, 7, 10-14 were tested for their activation of orphan nuclear receptor TR3 with the immunofluorescence technology in 50 µmol•L⁻¹. The results showed that compound 10 displayed moderate activity with the activity ratio of 76.38%, and the others were only about 50.0%.


Assuntos
Compostos Fitoquímicos/análise , Raízes de Plantas/química , Thymelaeaceae/química , Medicamentos de Ervas Chinesas/química
3.
Molecules ; 22(10)2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29039768

RESUMO

One new cassane diterpene possessing an unusual N bridge between C-19 and C-20 named caesalsappanin R (1), as well as another new diterpene caesalsappanin S (2), were isolated from the seeds of Caesalpinia sappanwith methanol extract. Their structures were determined by spectroscopic analysis and examined alongside existing data from prior studies. Their biological activities were profiled by their antiplasmodial activity.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Caesalpinia/química , Diterpenos/química , Diterpenos/farmacologia , Antimaláricos/isolamento & purificação , Diterpenos/isolamento & purificação , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Testes de Sensibilidade Parasitária , Extratos Vegetais/química , Extratos Vegetais/farmacologia
4.
Sensors (Basel) ; 17(7)2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28704960

RESUMO

We proposed the flexible arrayed lactate biosensor based on immobilizing l-lactate dehydrogenase (LDH) and nicotinamide adenine dinucleotide ( NAD + ) on nickel oxide (NiO) film, and which the average sensitivity could be enhanced by using graphene oxide (GO) and magnetic beads (MBs). By using GO and MBs, it exhibits excellent sensitivity (45.397 mV/mM) with a linearity of 0.992 in a range of 0.2 mM to 3 mM. According to the results of electrochemical impedance spectroscopy (EIS), the electron transfer resistance of LDH- NAD + -MBs/GPTS/GO/NiO film was smaller than those of LDH-NAD⁺/GPTS/GO/NiO film and LDH- NAD + /GPTS/NiO film, and it presented the outstanding electron transfer ability. After that, the limit of detection, anti-interference effect and bending test were also investigated.


Assuntos
Técnicas Biossensoriais , Grafite , L-Lactato Desidrogenase , Ácido Láctico , NAD
5.
Yao Xue Xue Bao ; 52(3): 425-9, 2017 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29979854

RESUMO

This study was designed to investigate triterpenoids from the roots of Rosa laevigata Michx. The silica gel column chromatography was used to separate the chemical constituents from the roots of Rosa laevigata Michx. HPLC was used to analyze its purity and chemical constitution. Spectroscopy methods were used to determine their structures. Five constituents were isolated and identified as19α-OH-3ß-E-feruloyl corosolic acid (1), 23-hydroxy-tormentic acid (2), 2α, 3ß, 19α, 23- tetrahydroxy-12-en-28-oleanolic acid (3), 2α, 3α, 20ß- trihydroxyurs-13 (18)-en-28-oic-acid (4), 2α, 3ß, 20ß-trihydroxyurs-13 (18)-en-28-oic-acid (5). Compound 1 was assigned as a new compound, compounds 4, 5 were obtained from the genus Rosa for the first time.


Assuntos
Raízes de Plantas/química , Rosa/química , Triterpenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Ácido Oleanólico , Extratos Vegetais , Triterpenos/química
6.
Biomed Pharmacother ; 82: 399-405, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27470378

RESUMO

BACKGROUND: Imbalance in bone remodeling causes osteoporosis. PURPOSE: In the present study, we identified that protocatechuic acid inhibits osteoclast differentiation and induces apoptosis in RAW264.7 murine macrophage cells. METHODS: Tartrate-resistance acid phosphatase (TRAP) activity was used to determine osteoclast formation. Oxidative stress was analyzed through ROS, lipid peroxide and antioxidant enzyme activities. Osteoclast and inflammatory marker expressions were determined through western blot. Apoptosis induction was determined through membrane potential analysis, Cyt c release and caspase activation. RESULTS: Protocatechuic acid dose dependently reduced RANKL-induced tartrate-resistance acid phosphatase (TRAP) activity and multinucleated osteoclasts formation. Protocatechuic acid inhibited oxidative stress by reducing ROS and lipid peroxide levels with concomitant increase in antioxidant status. Osteoclast specific marker expression (MMP, c-Src, TRAP, TRAF-6, Cathepsin) and transcription factor AP-1 and NFATc1 expression were significantly down regulated by protocatechuic acid. Further, MAPK activation and inflammatory proteins such as NF-kB and COX-2 expressions were significantly down regulated by protocatechuic acid treatment. Further, protocatechuic acid enhanced Nrf-2 translocation into the nucleus. In mature osteoclasts, protocatechuic acid induced apoptosis by inducing mitochondrial membrane potential, cytochrome c release and caspase activation. INTERPRETATION: The present findings shows evidence that, protocatechuic acid prevents osteoclast differentiation through regulating oxidative stress, inflammation and inducing apoptosis in RAW264.7 murine macrophage cells.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Hidroxibenzoatos/farmacologia , Osteoclastos/citologia , Animais , Biomarcadores/metabolismo , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ligante RANK/farmacologia , Células RAW 264.7 , Fatores de Transcrição/metabolismo
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(1): 82-4, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19565856

RESUMO

INTRODUCTION: To develop a model for forecasting the mortality of stroke in Tianjin, China. The time series of stroke mortality from 1999 Jan. to 2006 Dec. in Tianjin city were subjected. Circle distribution analysis was used to verify the trend of time concentration. Multiple seasonal autoregressive integrated moving average model [ARIMA (p, d, q) (P, D, Q) s], based on model identification, estimation and verification of parameter, and analysis of the fitting of model, was established. Most of the deaths from stroke occurred in January and had a cycle of 12 months. An ARIMA model (0, 1, 0) x (0, 1, 1)12 was established (1--B) (1-- B12) lnx(i) = 0.001 + (1--0.537 B12)epsilon(t). CONCLUSION: ARIMA & Circle Distribution analysis is an important tool for stroke mortality analysis. Potentially it has a high practical value on the surveillance, forecasting and prevention of stroke mortality.


Assuntos
Modelos Estatísticos , Acidente Vascular Cerebral/mortalidade , Causas de Morte , China/epidemiologia , Humanos , Distribuições Estatísticas , Acidente Vascular Cerebral/epidemiologia , Fatores de Tempo
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