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Sun Y.-Y.,Huaihai Institute of Technology | Sun Y.-Y.,Marine Innovation and Technology | Wang H.,Beijing Institute of Medical Device Testing | Guo G.-L.,Huaihai Institute of Technology | And 3 more authors.
Environmental Science and Pollution Research | Year: 2016

Ten compounds (1~10) were successfully isolated from green algae Ulva prolifera through the combination of silica gel column chromatography, Sephadex LH-20 column chromatography and repeated preparative thin-layer chromatography. These ten compounds showed antialgal activity against red tide microalgae. Among them, compounds 3, 6, and 7 showed stronger antialgal activity against red tide microalgae. Furthermore, their structure was identified on the basis of spectroscopic data. There are three glycoglycerolipids: 1-O-octadecanoic acid-3-O-β-d-galactopyranosyl glycerol (2), 1-O-palmitoyl-3-O-β-d-galactopyranosyl glycerol (4), and 1-O-palmitoyl-2-O-oleoyl-3-O-β-d-galactopyranosyl glycerol (5); two monoglycerides: glycerol monopalmitate (1), 9-hexadecenoic acid, 2,3-dihydroxypropyl ester (3); two terpenoids: loliolide (6) and lsololiolide (7); one lipid-soluble pigments: zeaxanthin (8); one sterol: cholest-5-en-3-ol (9); and one alkaloid: pyrrolopiperazine-2,5-dione (10). These compounds were isolated from U. prolifera for the first time, and compounds 2, 3, 5, and 8 were isolated from marine macroalgae for the first time. © 2015, Springer-Verlag Berlin Heidelberg.

Cao B.,University of Science and Technology Beijing | Cao B.,Beijing Institute of Medical Device Testing | Zheng Y.,University of Science and Technology Beijing | Xi T.,University of Science and Technology Beijing | And 6 more authors.
Biomedical Microdevices | Year: 2012

Sustained release of copper (Cu) ions from Cucontaining intrauterine devices (CuIUD) is quite efficient for contraception. However, the tissue surrounding the CuIUD is exposed to toxic Cu ion levels. The objective for this study was to quantify the concentration dependent cytotoxic effects of Cu ions and correlate the toxicity due to Cu ion burst release for two popular T-shaped IUDs-TCu380A and TCu220C on L929 mouse fibroblasts. Fibroblasts were cultured in 98 well tissue culture plates and 3-(4,5-dimethylth iazol-2-yl)-2,5- diphehyltetrazolium bromide (MTT) assay was used to determine their viability and proliferation as a function of time. For cell seeding numbers ranging from 10,000 to 100,000, a maximum culture time of 48 h was identified for fibroblasts without significant reduction in cell proliferation due to contact inhibition. Thus, for Cu cytotoxicity assays, a cell seeding density of 50,000 and a maximum culture time of 48 h in 96 well plates were used. 24 h after cell seeding, culture media were replaced with Cu ion containing media solutions of different concentrations, including 24 and 72 h extracts from TCuIUDs and incubated for a further 24 h. Cell viability decreased with increasing Cu ion concentration, with 30 % and 100 % reduction for 40 ìg/ml and 100 ìg/ml respectively at 24 h. The cytotoxic effects were further evaluated using light microscopy, apoptosis and cell cycle analysis assays. Fibroblasts became rounded and eventually detached from TCP surface due to Cu ion toxicity. A linear increase in apoptotic cell population with increasing Cu ion concentration was observed in the tested range of 0 to 50 ìg/ml. Cell cycle analysis indicated the arrest of cell division for the tested 25 to 50 ìg/ml Cu ion treatments. Among the TCuIUDs, TCu220C having 265 mm2 Cu surface area released 9.08±0.16 and 26.02±0.25 ìg/ml, while TCu380A having 400 mm2 released 96.7±0.11 and 159.3±0.15 ìg/ml respectively following 24 and 72 h extractions. The effects of TCuIUD extracts on viability, morphology, apoptosis and cell cycle assay on L929 mouse fibroblasts cells, were appropriate for their respective Cu ion concentrations. Thus, a concentration of about 46 ìg/ml (~29 ìM) was identified as the LD50 dose for L929 mouse fibroblasts when exposed for 24 h based on our MTT cell viability assay. The burst release of lethal concentration of Cu ions from TCu380A, especially at the implant site, is a cause of concern, and it is advisable to use TCuIUD designs that release Cu ions within cytotoxic limits yet therapeutic, similar to TCu220C. © 2012 Springer Science+Business Media, LLC.

Zhang J.,Peking Union Medical College | Zhang J.,Beijing Institute of Medical Device Testing | Peng Y.,Peking Union Medical College
Computing in Cardiology | Year: 2011

This paper is aimed to explore the possibility in evaluating the state of cardiac autonomic nerve based on paired short-term heart rate variability (HRV) and QT variability (QTV) indexes. Fantasia Database and Normal Sinus Rhythm Database were used as data source. Using short-term symbolic analysis and mutual information (MI) estimation, the consistency of HRV and QTV and its influencing factors were investigated. The MI of paired HRV and QTV indexes had no significant difference according to age, sex and circadian rhythm, while there were significant differences in most HRV indexes at the same time. The proposed measure is expected to reduce the influence of individual difference and highlight that of some pathological states. © 2011 CCAL.

Ning J.,Kunming University of Science and Technology | Yang C.,Kunming University of Science and Technology | Yang C.,Beijing Institute of Medical Device Testing | Bi L.,Kunming University | And 3 more authors.
Asian Journal of Chemistry | Year: 2015

Vortex-assisted surfactant-enhanced emulsification microextraction and high performance liquid chromatography (VASEME-HPLC) for the preconcentration and determination of trace amounts of scutellarin in urine was developed. Pentanol and Triton X-100 were used as the extraction solvent and emulsifier, respectively. The factors influencing the extraction, such as the kind and volume of the extraction solvent and emulsifier, pH were optimized. Under the optimum conditions, the linear dynamic range was between 0.04-24 μg/mL (r = 0.9977). The limit of detection (LOD, S/N = 3) was 1.3 ng/mL. The limit of quantification (LOQ, S/N = 10) was 3.9 ng/mL. The relative standard deviation (RSD) at 0.04 μg/mL level of scutellarin (n = 5) was found to be 3.1%. Good recovery results (86.3-93.6%) were obtained when the proposed method was applied to determine scutellarin in urine samples. © 2015, Chemical Publishing Co. All rights reserved.

Sun Y.,Huaihai Institute of Technology | Wang H.,Beijing Institute of Medical Device Testing | Guo G.,Huaihai Institute of Technology | Pu Y.,Huaihai Institute of Technology | Yan B.,Huaihai Institute of Technology
Carbohydrate Polymers | Year: 2014

Three polysaccharides, IPSI-A, IPSI-B and IPSII, were successfully isolated from the marine microalgae Isochrysis galbana through a combination of anion-exchange column chromatography and repeated gel chromatography. These three polysaccharides were demonstrated to have moderate scavenging activities against superoxide and hydroxyl radicals and moderate reductive power in a concentration-dependent manner. The IPSII demonstrated more effective antioxidant activities than IPSI-A and IPSI-B. IPSII had a molecular weight of 15.934 kDa belonging to a β-type heteropolysaccharide with a pyran group and primarily contained mannose with variable amounts of glucose, galactose and rhamnose based on an analysis of infrared spectroscopy (IR), electrospray ionization-mass spectrometry (ESI-MS) and 1H nuclear magnetic resonance (1H NMR). © 2014 Elsevier Ltd.

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