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The preparation of microfluidic chip is investigated and improved in this research. Etching and bonding, which are key procedures in the microfluidic chip fabrication, were investigated and optimized. The effects of two kinds of etching formula were compared and the influences of etching time and the direction of oscillation during etching were studied. Moreover, it was found that the thermal bonding method with high temperature had longer lifetime than bonding under normal temperature. Using the new prepared chip, native protein electrophoresis has been realized. The increase of yield, the decreased of preparation efforts and the high performance of protein separation have been achieved by the improvement of chip preparation. This research exhibits good prospect of application in complicated biological separation. [ABSTRACT FROM AUTHOR]

Six constituents were repeatedly isolated and purified from a soft coral Sinularia sp. by silica gel and Sephadex LH-20 chromatographies. On the basis of spectroscopic data of ID NMR, 2D NMR and EI-MS, their chemical structures were identified as lobocrassolide, lobohedleolide, (7Z)-lobohedleolide, 2-epi-llZ-lobohedleohde, 1, 2-benzenedicarboxylic acid diisobutyl ester, ergosta-5-en-3β-ol. The compounds of cembranoid diterpenes are gained from this organism for the first time. [ABSTRACT FROM AUTHOR]

Thermoresponsive poly( N-isopropylacrylamide) (PNIPAAm) brushes were densely grafted onto silica surface via surface-initiated atom transfer radical polymerization (SI-ATRP). The grafting reaction started from the surfaces of 2-bromoisobutyratefunctionalized silica particles in 2-propanol aqueous solution at ambient temperature using CuCl/CuCl/ N,N,N′,N′,N″-pentamethyldiethylenetriamine (PMDETA) as the catalytic system. Based on thermogravimetric analysis (TGA) results, the grafting amount and grafting density of PNIPAM chains on the surface of silica were calculated to be 1.29 mg/ m and 0.0215 chains/nm, respectively. The gel permeation chromatography (GPC) result showed the relatively narrow molecular weight distribution ( M/ M= 1.21) of the grafted PNIPAAm. The modified silica particles were applied as high-performance liquid chromatography (HPLC) packing materials to successfully separate three aromatic compounds using water as mobile phase by changing column temperature. Temperature-dependent hydrophilic/hydrophobic property alteration of PNIPAAm brushes grafted on silica particles was determined with chromatographic interaction between stationary phase and analytes. Retention time was prolonged and resolution was improved with increasing temperature. Baseline separation with high resolution at relatively low temperatures was observed, demonstrating dense PNIPAAm brushes were grafted on silica surfaces. [ABSTRACT FROM AUTHOR]

A new assay has been developed to analyze the secretome of human SH-SY5Y by OFFGEL and LC-MS combined with the software of bioinformatics. The proteins collected from the extracellular SH-SY5Y mediums have been digested and fractionated by the OFFGEL, and then different fractions were performed by reverse phase liquid chromatography with electrospray tandem mass spectrometry. The 88 potential secretory proteins from Mascot results were predicted and screened by the bioinformatics software called SignaIP. Only 31 proteins have been confirmed by the SingaIP. Based on the neural networks and hidden Markov models of SignaIP, which could increase the identification probability, it was found that the CERU_HUMAN was one of secretory proteins with the location of signal peptide cleavage sites between 19 and 20 amino acid. The new assay would play more and more important role in the application of secretome analysis. [ABSTRACT FROM AUTHOR]

Chromatographic packing materials containing poly (N-isopropylacrylamide-co-2-acrylamido-2-methyl propane sulfonic acid) and poly(N-isopropylacrylamide-co-N-tert-butylacrylamide) were prepared via conventional radical polymerization. Characterization was performed with thermogravimetric analysis (TGA) and elemental analysis to determine the grafting ratio. Mixtures of Val, Leu, Phe, Trp, Art and Ala derivatized with phenylisothiocyanate were separated using prepared stationary phases by HPLC. The results indicated that separation can be accomplished only by controlling column temperatures, which proves that chromatographic retention of analytes alters with the change of column temperature, and the materials are of temperature-responsive property. [ABSTRACT FROM AUTHOR]

Using HP20 macroporous resin, polyamide, Sephadex-LH20 and YMC preparation column (ODS), four kinds of C-glycoside flavones were isolated from the leaves of Belamcanda chinensis grown in Hainan island. Combined with the measurement of melting points and chemical reactions, the structures of C-glycoside flavones were identified by analyzing the spectroscopic data of UV, ¹H NMR, 13C NMR, MS. They are compound I 2″-O-rhamnosylisovitexin; compound II 2″-O-rhamnosylswertisin; compound III isovitexin and compound IV swertisin. All the compounds are isolated from the Iridaceae plants for the first time. [ABSTRACT FROM AUTHOR]

Bio-functionalized chromatography--capillary electrophoresis was used in investigating the interaction between semicarbazide-sensitive amine oxidase(SSAO), its substrate benzylamine as well as its inhibitor 2-BrEA. SSAO activity detection showed that SSAO could keep 70%~ 85% activity of its free form after being immobilized onto liposome. The active immobilized SSAO was added to the PBS. With the increase of the immobilized enzyme concentration, the effective mobility of its specific substrate, benzylamine, decreased from 4.06 x 10-4 cm² · V-1 · s-1 to 0.81X10-4 cm² · V-1 · s-1 at pH=5, and from 3.91X10-4 cm² · V-1 · s-1 to 0.29X10-4 cm² · V-1 · s-1 at pH=7. If the concentration of the inhibitor 2-BrEA in the buffer was increased from 10-6 mol · L-1 to 10-1 mol · L-1, the effective mobility of benzylamine would increase from 1.42X10-4 cm² · V-1 · s-1 to 2.22X10-4 cm² · V-1 · s-1. [ABSTRACT FROM AUTHOR]

β-cyclodextrin-modified membrane was applied in the chiral separation of 1-methyl-6,7-dihydroxy-1, 2, 3, 4-tetrahydroisoquinoline (Salsolinol). From the results of HPLC, it was observed that β-cyclodextrin-modified membrane possess the ability of chiral discrimination to the Sal. Through one time diosmosis experiment of membrane circulation, the proportion of Sal changed from 0.87 to 1.55. Gaussian 98 software was used to study the difference of interaction energies between R, S-Sal with β-CD. Calculation were carried out in order to study the relevant mechanism. [ABSTRACT FROM AUTHOR]

Active components on promoting blood circulation and removing blood stasis were virtually screened by Discovery Studio with thrombin as receptor and the subjects were determined to be detected the effects on thrombin activities and anti-aggregation in vitro. Experimental data shows that the results of pharmacological effects correspond with that of the virtual screening. The subjects including loureirin A, loureirin B, loureirin C, 7-hydroxy-4'-methoxy flavane, and 4', 7-dihydroxy-homoisoflavane can inhibit the activities of thrombin in vitro effectively. It is hypothesized that they play a crucial role in promoting blood circulation and removing blood stasis. [ABSTRACT FROM AUTHOR]

By HPLC-MS n and HRMS analyses, the structures of 52 polyoxypregnane glycosides were rapidly inferred from Dregea sinensis Hemsl on the basis of their sodium-cationized molecules [M + Na] + and predominant diagnostic ions resulting from the saccharic chain on C3 and the neutral loss of substituent on C11 and C12. Compounds 1 and 7 significantly inhibited LPS-stimulated splenocyte proliferation in vitro .[Formula: see text].

Objective: To investigate the effect of androgen receptor (AR) on IgG protein expression and the proliferation and migration of prostate cancer cells., Methods: Western blotting was used to detect the expression of AR protein and IgG in androgen-dependent prostate cancer LNCap cells and castration-resistant prostate cancer PC-3 cells. In AR-overexpressing cells (PC-3-AR cells) established by transfecting PC-3 with AR gene (pCDNA3.1) and LNCap cells with small interfering RNA-mediated AR silencing (LNCap-siAR cells) were analyzed for expressions of AR protein and IgG with Western blotting; the expression of IgG mRNA was detected by Q-PCR, and the cell proliferation and migration were assessed with MTT assay and wound healing assay, respectively., Results: Compared with PC-3 cells, LNCap cells expressed a higher level of AR protein and a lower level of IgG (P<0.05). PC-3-AR cells showed attenuated proliferation and migration with a lowered expression of IgG (P<0.01), while LNCap-siAR cells showed enhanced proliferation and migration with increased expression of IgG (P<0.01)., Conclusion: The expression of AR is inversely correlated with IgG and is associated with the proliferation and migration of prostate cancer cells in vitro.

There are statistical data indicating that diabetes is a risk factor for Parkinson's disease (PD). Methylglyoxal (MG), a biologically reactive byproduct of glucose metabolism, the levels of which have been shown to be increase in diabetes, reacts with dopamine to form 1-acetyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (ADTIQ); this formation may provide further insight into the connection between PD and diabetes. In this study, we investigated the role of ADTIQ in these two diseases to determine in an aim to enhance our understanding of the link between PD and diabetes. To this end, a cell model of hyperglycemia and a rat model of diabetes were established. In the cell model of hyperglycemia, compared with the control group, the elevated glucose levels promoted free hydroxyl radical formation (p<0.01). An ADTIQ assay was successfully developed and ADTIQ levels were detected and quantified. The levels of its precursors, MG and dopamine (DA), were determined in both the cell model of hyperglycemia and the rat model of diabetes. The proteins related to glucose metabolism were also assayed. Compared with the control group, ADTIQ and MG levels were significantly elevated not only in the cell model of hyperglycemia, but also in the brains of rats with diabetes (p<0.01). Seven key enzymes from the glycolytic pathway were found to be significantly more abundant in the brains of rats with diabetes. Moreover, it was found that adenosine triphosphate (ATP) synthase and superoxide dismutase (SOD) expression levels were markedly decreased in the rats with diabetes compared with the control group. Therefore, ADTIQ expression levels were found to be elevated under hyperglycemic conditions. The results reported herein demonstrate that ADTIQ, which is derived from MG, the levels of which are increased in diabetes, may serve as a neurotoxin to dopaminergic neurons, eventually leading to PD.

Objective: To study the suitable oxygen concentration in hypoxic preconditioning., Methods: Short-term and long-term intermittent hypoxia modes were designed and the effects of various oxygen concentrations on body weight, blood oxygen saturation, swimming capability were analyzed., Results: The rate of body weight gain in rat model decreased gradually when exposed to hypoxia environment for long time. When the concentration of oxygen changed from 15% to 8%, accompanied with the decreasing of oxygen concentration, a platform was observed in blood oxygen saturation of rat model after hypoxic preconditioning training. Rat swimming capability improved significantly. After trained in 10% hypoxia environment, the swimming capability of kunming mice improved obviously., Conclusion: Proper level of hypoxic preconditioning training could improve hypoxia tolerance and enhance the rat sport capability significantly. 15%-10% oxygen concentration range could be regarded as a helpful effective area for hypoxic preconditioning, 10% oxygen concentration might be the eligible concentration for hypoxic preconditioning training.

Objective: To study the flavonoids compounds from the effective fraction of Thesium chinese in anti-inflammation., Methods: The isolation and purification were carried out by many kinds of column chromatographic techniques. The flavonoids were analyzed by HPLC-DAD, and elucidated by 1H-NMR, 13C-NMR and ESI-MS., Results: Five compounds were obtained and therir structures were determined as kaempferol-3-O-glucoside (I), rutinoside (II), luteolin-7-O-glucoside (III), kaempferyl 5-methyl ether (IV), apigenin-5-O-neohesperidoside (V)., Conclusion: Compounds IV and V are isolated from this plant for the first time.

Objective: To establish a determination method of astragulin in Thesium chinese., Method: RP-HPLC analytical method was established using a Polaris C18 column and acetonitrile-water (23:77) as the mobile phase, with a flow rate of 10 mL x min(-1), detected at 346 nm. The method of sample is refluxing exation by 50% alcohol for 2 times., Result: The content of astragulin was from 0. 120% to 0. 155%, in different groups of T. chinese collected from the same location., Conclusion: The method was validated to show convenient and reliable.

Samples extracted from the root of Iris japonica Thunb were analyzed and the optimal HPLC chromatographic conditions was confirmed. Through analyzing the chromatography, the HPLC-FPS of Iris japonica Thunb was established.