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Latest Paper:
Anal Bioanal Chem. 2012 May 11;:
22576658
Xianjun Jia,
Hong Li,
Jing Luo,
Qing Lu,
Yan Peng,
Liying Shi,
Liping Liu,
Shuhu Du,
Guijun Zhang,
Lina Chen
School of Pharmacy, Nanjing Medical University, Nanjing, 210029, China.
Computational simulation and Doehlert experimental optimization were done for the rational design of a core-shell molecularly imprinted polymer (CS-MIP) for use in the highly selective separation of Tanshinone IIA (TSIIA) from the crude extracts of Salvia miltiorrhiza Bunge (SMB). The functional monomer layer of the polymer shells directed the selective occurrence of imprinting polymerization at the surface of silica through the copolymerization of vinyl end groups with functional monomers and also drove TSIIA templates into the formed polymer shells through the charge-transfer complex interactions between TSIIA and the functional monomer layer. As a result, the maximum rebinding capacity was achieved with the use of optimal grafting ratio by the Doehlert design. The CS-MIP exhibited high recognition selectivity and binding affinity to TSIIA. When the imprinted particles were used as dispersive solid phase extraction sorbents, the recovery yield of TSIIA reached 93 % by a one-step extraction from the crude extracts of SMB, and the purity of TSIIA was larger than 98 % by HPLC analysis. These results show the possibility of a highly selective separation and enrichment of TSIIA from the SMB using the TSIIA-imprinted core-shell molecularly imprinted polymers.
W. Zhang, Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing, China, zhangwz2002@sina.com.
Objective: L-ascorbic acid can be pro-oxidant and anti-oxidant in different reaction. This study aims to test the effects about products of oxidized L-Ascorbic Acid on acellular DNA. Measurement: Acellular DNA, nuclear DNA fixed on slides, are used in our experiment. There are four groups and one negative. Negative control is sham-treated with buffer(pH 7.2 and AA/ H2O2/fenton free). Experimental groups are treated separately with 0.06 mM L-ascorbic acid (AA) alone(exposed in air), 0.06 mM L-ascorbic acid (AA) alone(no exposure in air), 1.2 mM hydrogen peroxide (H2O2) alone, and a mixture of final concentration of 0.03 mM L-ascorbic acid and 0. 6 mM hydrogen peroxide (AA+ H2O2). Each experimental group consists of 4 slides and each slide is treated for 4 hours at 4 ℃ in a dark place. The DNA damage is quantified by alkaline Comet Assay. The comet images are analysed by Comet A1.0 software. Differences among groups are compared with SPSS 11.0. Results: DNA singlestrand breakage is found to be treatment-dependent in the following sequence: AA+ H2O2> AA(oxidized)> H2O2, AA(without oxidization) and Control. Conclusion: Acellular DNA can tolerate the low concentration H2O2, but is sensitive to free radical. The results indicate that AA expose in air and mixture of AA and H2O2 can produce •OH and L-dehydroascorbate (DHA), •OH can damage DNA.
LICOS Centre for Institutions and Economic Performance, University of Leuven (KU Leuven), Leuven 3000, Belgium.
China's milk scandal is well known for causing the nation's largest food safety crisis and for its effect on thousands of children. Less, however, is known about the effect on the other victim: China's small dairy farmers. Although small backyard producers were not the ones that added melamine to the milk supply, the incomes of dairy farmers fell sharply after the crisis. In response, one of the actions taken by the government was to encourage small dairy producers to check into production complexes that were supposed to supply services, new technologies, and provide for easy/bulk procurement of the milk produced by the cows of the farmers. Because both farmers and their cows were living (and working) away from home, in the rest of the paper we call these complexes cow hotels. In this paper we examine the dynamics of China's dairy production structure before and after the milk scandal. In particular, we seek to gain a better understanding about how China's policies have been successful in encouraging farmers to move from the backyard into cow hotels. We also seek to find if larger or smaller farmers respond differently to these policy measures. Using data from a sample of farmers from dairy-producing villages in Greater Beijing, our empirical analysis finds that 1 yr after the milk scandal, the dairy production structure changed substantially. Approximately one quarter (26%) of the sample checked into cow hotels after the milk scandal, increasing from 2% before the crisis. Our results also demonstrate that the increase in cow hotel production can largely be attributed to China's dairy policies. Finally, our results suggest that the effects of government policy differ across farm sizes; China's dairy policies are more likely to persuade larger farms to join cow hotels. Apparently, larger farms benefit more when they join cow hotels. Overall, these results suggest that during the first year after the crisis, the government policies were effective in moving some of the backyard farmers into cow hotels (although 60% farmers remained backyard producing).
Department of Ultrasound, Shanghai First People's Hospital, School of Medicine, Shanghai Jiaotong University, 100 Haining Rd, Hongkou District, 200080 Shanghai, China. du_lf@163.com.
Objectives- This study aimed to evaluate the diagnostic value of acoustic radiation force impulse (ARFI) elasticity imaging for differentiating between benign and malignant thyroid lesions. Methods- Hospitalized patients needing thyroid surgery were evaluated. After routine thyroid sonography, the patients underwent ARFI elasticity imaging. Virtual Touch tissue imaging (VTI) and Virtual Touch tissue quantification (VTQ; Siemens Medical Solutions, Mountain View, CA) were used to qualitatively and quantitatively analyze the elasticity and hardness of nodules. For statistical analysis, the Student t test, analysis of variance, and the χ(2) test were used to compare the elastic parameters. Results- Of the 98 thyroid nodules observed in 72 hospitalized patients, 56 were nodular goiters, 16 thyroid adenomas, 4 thyroiditis, and 22 thyroid malignancies, with mean VTQ values ± SD of 2.034 ± 0.484, 1.835 ± 0.364, 2.293 ± 0.787, and 3.941 ± 1.393 m/s, respectively. The elastic parameters of malignant nodules were significantly higher than those of benign nodules (P <.001) and the surrounding thyroid parenchyma (P <.001). There was no significant difference between the VTQ value of benign nodules and that of the surrounding normal thyroid parenchyma (P >.05). For differentiating between benign and malignant nodules, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accordance rate were 86.36%, 93.42%, 79.17%, 95.95%, and 91.84% based on the standard VTQ value (2.555m/s). In total, 77.6%(59 of 76) of the benign nodules showed softer and equal images in the VTI mode, and 77.3%(17 of 22) of the malignant nodules showed stiffer images (P <.001). Conclusions- Acoustic radiation force impulse imaging has high sensitivity and specificity in evaluating benign and malignant thyroid nodules and therefore had good diagnostic value in clinical applications.
Reprod Sci. 2012 Apr 24;:
22534323
Polycystic ovary syndrome (PCOS) is the most common endocrinopathy associated with infertility and metabolic disorder in women of reproductive age. Although the clinical and biochemical features are heterogeneous with individuals, the most widely accepted clinical characteristics of PCOS are oligo- or anovulation combined with hyperandrogenism. With the higher rate of implantation failure after induction of ovulation or higher risk of spontaneous miscarriage after pregnancy, the reduced fertility is apparently attributed not only to anovulation but also to endometrial dysfunction in patients with PCOS. Here we review the features of the endometrial abnormalities in women with PCOS. The ability to improve the endometrial functions is of potential therapeutic targets to increase reproductive outcome of women with PCOS.
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
The silica/polydimethylsilane (PDMS) hybrid nanoparticles were successfully synthesized by a novel solvent adjustment route. The as-prepared hybrid nanoparticles were characterized by transmission electron microscopy, UV-vis spectra, and IR spectra. The possible mechanism for the formation of silica/PDMS nanoparticles was discussed. The adjustment of solvents is a very important factor since it could tune the surface ligands and improve the coordination ability. On the other hand, it could also tune the interaction between precursors, intermediate or the target hybrid materials and guarantee the monodispersion of prepared nanoparticles. With the merits of PDMS and silica, the as-prepared SiO2-PDMS hybrid nanoparticles have a good application in hard coating material.
Molecules. 2012 ;17 (4):3794-804
22453930
School of Food Science and Technology, Henan University of Technology, Zhengzhou 450001, China. myx366@163.com.
The effects of zein ratio, concentration of glycerol, liquid-solid ratio, ethanol concentration, pH and heat-treatment temperature on the properties of zein/wheat gluten composite films were researched. The results showed that elongation (E) increased with an increase in glycerol or ethanol concentrations, but it first increased and then decreased with increasing zein/wheat gluten ratio, heat-treatment temperature, pH and the ratio of liquid to solid; Tensile strength (TS) increased with the increase in heat-treatment temperature and pH, and decreased with the increase in glycerol or ethanol concentrations, and it reached a maximum value when the ratio of zein/wheat gluten was 20%, but had a minimum value when the ratio of liquid to solid was 8:1; Water Vapor Permeability (WVP) increased with an increase of glycerol concentration and the ratio of liquid to solid and ethanol concentration, but it decreased with increasing zein/wheat gluten ratio, heat treatment temperature, and pH of the film forming solution.
Department of Chinese Medicine and Pharmacy, School of Pharmacy, Jiangsu University, China.
BACKGROUND Rutin is a bioflavonoid of strong immunostimulating activity from the Toonea Sinensis Folium, which has shown a significant ability to increase the survival rate of white shrimp with bacterial infection. However, no method for the quantitation of this active ingredient in the herb has been reported to date. MATERIALS AND METHODS A reversed phase-high performance liquid chromatography-diode array detector (RP-HPLC-DAD) method was developed to quantify Rutin in the Toonea Sinensis Folium, with the HPLC conditions optimized, followed by validation for linearity, accuracy, precision, limit of detection (LOD), repeatability, and stability. Then, the established method was used to determine the content of Rutin in two samples. RESULTS The separation was performed on a Waters XBridge Shield RP18 column (150 mm × 4.6 mm, 5 μm) kept at 25°C, and acetonitrile and water containing 0.1% acetate acid (18:82, v / v)-composed mobile phase was constantly driven at 1.0 mL / minute during the analysis. Twenty microliters of sample solution or standard solution were injected into the HPLC system and 254 nm was selected to monitor the separation. A strong linear relationship between the peak area and concentration of Rutin was observed within the range of 0.01044 - 0.2610 mg / mL (r(2)= 1.0000). The LOD was 0.03915 μg / mL, and recovery of Rutin was from 97.6 to 99.6%. In addition, the method was also validated to be repeatable, stable, precise, and accurate. CONCLUSIONS An efficient and reliable RP-HPLC-DAD method was established, which could be used for routine analysis of Rutin in Toonea Sinensis Folium and to assist in the quality control of this herb.
Pharmazie. 2012 Jan ;67 (1):59-62
22393832
Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing, China.
In the present study, the Caco-2 monolayer model and a four-site rat intestinal perfusion model were used to investigate the effects of vitamin E tocopherol polyethylene glycol succinate 1000 (TPGS) on the intestinal absorption of icariside II. Icariside II was analyzed by ultra-performance liquid chromatography (UPLC). After that its apparent permeability coefficients (Papp) and effective permeability (P*(eff)) were calculated. In the Caco-2 cell model, Papp values from the apical (AP) to the basolateral (BL) of icariside II were increased and its efflux ratios were markedly reduced in the presence of TPGS. However, either 0.25 mg/mL or 0.5 mg/mL of TPGS had no significant difference in promoting the absorption of icariside II. In four-site rat intestinal perfusion model, P*(eff) of icariside II were significantly increased by 0.5 mg/mL of TPGS in ileum and colon. The results suggest that TPGS could promote the intestinal absorption of icariside II.
China Institute of Atomic Energy, Beijing, China.
A 14 MeV medical cyclotron with the external ion source has been designed and is being constructed at China Institute of Atomic Energy. The H(-) ion will be accelerated by this machine and the proton beam will be extracted by carbon strippers in dual opposite direction. The compact multi-cusp H(-) ion source has been developed for the cyclotron. The 79.5 mm long ion source is 48 mm in diameter, which is consisting of a special shape filament, ten columns of permanent magnets providing a multi-cusp field, and a three-electrode extraction system. So far, the 3 mA∕25 keV H(-) beam with an emittance of 0.3 π mm mrad has been obtained from the ion source. The paper gives the design details and the beam test results. Further experimental study is under way and an extracted beam of 5 mA is expected.
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