Objective To isolate and identify the anti-MRSA bioactive fraction from the fermentation broth of the marine-derived actinomycete AM105.Methods By means of silica gel column chromatography,preparative TLC and Sephadex LH20 column chromatography,the bioactive component was purified.The structure was determined by the spectral methods.Results and Conclusion The bioactive component AM105-Ⅱ was purified and the spectra showed that AM105-Ⅱ was composed of rifamycin S and its isomer,named isorifamycin S,which is a novel structure compound.Its antibacterial activity is better than rifamycin SV according to MIC.

Objective To investigate the therapeutic effects of treating chloasma with Huoxue Xiaoban Decoction.Methods A total of 80 cases were randomly recruited into a control group and a treatment group, 40 cases in each group. The treatment group was treated with Huoxue Xiaoban Decoction, while the control group was treated with high dose of Vitamin C. After both groups were treated for a therapeutic course of four weeks, the therapeutic effects were compared between them. Results The total effective rate was 85.0% and 47.5% in the treatment group ands the control group respectively, showing significant difference between the two group (χ2= 12.26, P＜0.01 ) . Conclusion Huoxue Xiaoban Decoction was effective in treating chloasma.

The effects of carbon source, Sodium glutamate, salinity, and incubation temperature on the growth of Thraustochytrium aureum H0 and the production of docosahexaenoic acid were studied. The time course of the cell growth of Thraustochytrium aureum H0 was determined. The results showed that glucose is the best carbon souce and the optimum concentrations of glucose and Sodium glutamate are 30g ? L-1 and 5g ? L-1 respectively. The suitable salinity is half of salinity of sea water. Under the optimum culture conditions, 6. 2g ? L-1 of the dry cell weight and 0. 51g ? L-1 of the docosahexaenoic acid were obtained.

Objective To investigate the efficacy and safety of mycophenolate mofetil (MMF) for refractory autoimmune 1iver disease:Methods Six patients with autoimmune liver disease who had failed MMF treatment and variation of biochemical indexes.adverse effects of the MMF treatment were recorded.Results After MMF treatment.the serum 1evels of alanine aminotransferase (ALT) were decreased to nOrmal level in three of four patients with higher ALT.The serum levels of alkaline phosphatase (ALP) were decreased to more than fifty percent of normal level in four of five patients with higher ALP.The serum levels of γ-glutamyhransferase (GGT) were decreased to more than fifty percent of normal level in all five patients with higher GGT.The serum levels of immunoglobulin G (IgG) and γ-globulin were decreased to normal level in all two patients who had elevated IgG and r-globulin levels.The serum levels of total bilirublin and total bile acid.the count of white blood cell and platelet had no change.There were no adverse effects in a11 six patients.Conclusion MMF treatment for early refactory autoimmune liver disease is effective with few sideeffects.

Mixed saponin molecules in the extraction of Panax notoginseng(PNE) can be effectively desorpted into the molecular ionization for measurement and analysis by mass analyzer from matrix assisted laser desorption ionization-time of flight-mass spectrometry(MALDI-TOF MS). The saponin samples with chromatography purity were directly analyzed by MALDI-TOF MS, which indicated that the sensitivity of the method was higher than that of RP-HPLC. A technology of MALDI-TOF MS was directly employed to analyze the saponin kinds and their relative contents in Panax notoginseng(PN) while the saponins were perfectly extracted from the Chinese traditional medicine of PN. It was indicated that there were at least 20 saponins consisting of different molecular structure and that the content of both ginsenoside Rg1 and notoginsenoside R1 in PNE was relative high. R1 saponin was extracted and identified to follow its metabolism pathway by both thin layer chromatography and MALDI-TOF MS, respectively. The saponin fingerprinting maps in PNE can be established to evaluate the quality of PE and to study both metabolism pathway and mechanism of extra minim saponins in vivo.

A special solid phase micro extraction ( SPME ) fibre was successfully attained by coating with a special adsorptive material on a porous stainless steel support. And the porous stainless steel support was prepared by electrochemical corrosion for the first time. The optimized erosion condition in this research was as follows: the current intensity of 30 mA, the stainless steel was etched in 2 mol/L hydrochloride solution for 1 min, then sonicated for 3 min; these procedures repeated 5 times. Meanwhile, the treated fiber coated 35 times in the sorbent solution with concentration of 5% ( m/V) in dichloromethane. The SPME fibre was applied to the analysis of gutter oil samples, and the performance of the SPME fibre for the headspace solid phase micro extraction of the exogenous impurities in gutter oil was specific, durable, stable and low-cost. The four detected trace level characteristic impurities in certain gutter oil were given as follows:42 . 7 mg/kg for acetic acid, 21. 6 mg/kg 3-butenenitrile, 71. 8 mg/kg carbon disulfide and 2. 8 mg/kg allylisothiocyanate.

A high-throughput method for screening drug multi residues was developed by quadrupole-time-of-flight( Q-TOF) mass spectrometry together with QuEChERS sample preparation technique. It has been used for the determination of 57 drugs, such as tetracyclines ( TCs ) , sulfonamides ( SAs ) , quinolones ( QNs ) , triphenylmethanes (TPMs), estrogens (ETs), androgens (AGs) and glucocorticoids (GCs) in fish. The optimized pretreatment conditions were examined. The target compounds were extracted with acetonitrile under the condition of Na2 EDTA-Mcllvaine buffer, and the usage of clean-up reagents was 25 mg anhydrous magnesium sulfate, 12. 5 mg octadecylsilane and 6. 25 mg N-Propylethylenediamine sorbent for extracted solvent of each milliliter. The positive results acquired by this high-throughput method were confirmed by liquid chromatography-tandem mass spectrometry ( LC-MS/MS) . The detection limit for these 59 drugs was in the range of 0. 5-5. 3 μg/kg. The method is time-saving, convenient, effective and wide coverage. Its sensitivity can meet the requirement of the detection of drug residues in aquatic products.

A high throughput screening method based on QuEChERS purification and stable isotope dilution-liquid chromatography coupled to high resolution time-of-flight mass spectrometry was developed for the simultaneous rapid determination of 86 kinds of glucocorticoids (GCs) in cosmetics.The analytes were extracted by acetonitrile, and then the extracts were purified using an improved QuEChERS method.The chromatographic separation was performed on a novel multiple chromatographic retention mechanisms column of Poroshell 120 PFP (100 mm × 2.1 mm, 2.7 μm) with gradient elution using 0.2% (V/V) acetic acid and acetonitrile as mobile phase.The accurate mass database of parent ions and mass spectra library of fragment ions of 86 GCs were established under positive ionization mode with electrospray ionization source.Based on the method described above, the qualitative identifications of the 86 GCs were accomplished without the contrast of standard substances.The results demonstrated that the linear range of this method was from 2 μg/L to 200 μg/L with good correlation coefficients of R2>0.99.The average recoveries of the 86 GCs ranged from 66.2% to 112.8%, and the relative standard deviation (RSDs) was 4.6%-13.9% at three different spiked levels.The limit of detection (LOD) and quantification (LOQ) were 0.006-0.015 mg/kg and 0.02-0.05 mg/kg, respectively.The method is simple, efficient, reliable and accurate, and is suitable for high throughput screening of 86 GCs added illegally in cosmetics.

AIM:To direct embryonic stem cells(ESCs)into hematopoietic stem cells(HSCs)in vitro by simulating the hematogenic microenvironment in human early embryonic aorta-gonad-mesonephero(AGM)region.METHODS:Murine E14 embronic stem cell line was used for two-step differentiation.In the first step of primary differentiation,E14 ESCs were seeded into semisolid methylcellulose-based medium containing bone morphogenesis protein 4(BMP4)and vascular endothelial growth factor(VEGF)for embryoid body(EB)formation.On days 3,6,9,12 and 15,single EB cells were analyzed for Flk-1+ cells amount through flow cytometry.In the second step,single cell from EB containing most Flk-1+ cells was further co-cultured with human AGM stromal cells in non-contact system.On co-culture days of 3,6,9 and 12 days,cells were collected for cell count,flow cytometry for Sca-1+c-kit+ cells analysis,and colony forming cell assay.RESULTS:During the EB formation,BMP4+VEGF promoted Flk-1+ cell genesis on day 9 at peak pencentage value of 27.53%?2.84%,which was statistically higher than that in control group as 8.77?1.10(P

Arapidscreeningmethodforthedeterminationofcarbamatepesticides(CBPs)residuesin vegetables by measuring acetylcholinesterase ( AChE ) inhibition rate using electrospray ionization mass spectrometry ( ESI-MS ) has been established. After pretreatment by QuEChERS method, sample solution reacts with AChE using acetylthiocholine as substrate. AChE inhibition rate was calculated by determination of the conversion of substrate to product ( thiocholine) using ESI-MS. The temperature, time and concentration conditions of enzymatic reactions have been optimized. The relationship between the concentration of 10 kinds of common CBPs and AChE inhibition rate was researched. Matrix effects of real vegetables were studied. The limit of detection ( LOD) , which was measured by 3 times of enzyme inhibition rate of pesticide-free vegetable samples, was 0. 01-0. 05 mg/kg. The results showed that the method was better than the current national standard method of china for rapid screening of pesticide residues and fully meet the requirements of maximum residue limits( MRL) for pesticides in food of national food safety standard. False positive results were avoided effectively due to its good ability of resistance matrix interference. The reliability was proved by analyzing vegetables with liquid chromatography-tandem mass spectrometry. The method is simple, rapid, sensitive, reliable, and can be used for the rapid, high-throughput screening of CBPs in vegetables.