Preparative resolution of gatifloxacin enantiomers with pre-column esterification strategy and comparing their enantioselectivity to bacteria and antibody / 生物医学与环境科学（英文）

Gatifloxacin (GFX) is a kind of chiral fluoroquinolones compound due to the methyl group at the C-3 position of the piperazine ring[1]. Although the enantiomers of GFX show similar levels of antimicrobial activity and pharmacokinetics[2], the other biological activities (i.e., toxicity or enantioselective recognition to various receptors in vivo) of GFX enantiomers have not yet been studied. With this in mind, we developed a rapid and cost-effective high performance liquid chromatographic (HPLC) separation procedure for GFX enantiomers with a pre-column esterification strategy. With significant enhancement of drug solubility and optimization for chromatographic conditions, the proposed method was scaled up to preparative HPLC to obtain optical active S-(-)- and R-(+)-GFX. The antibacterial activities of GFX enantiomers after preparative separation were further verified by measuring the Minimum Inhibitory Concentration (MIC) values against Escherichia coli ATCC 25922. In addition, the binding selectivity of GFX enantiomers to protein receptor were evaluated by antibody using enzyme-linked immunosorbent assay (ELISA) for the first time.

Combination of tamsulosin and tolterodine alleviates refractory lower urinary tract symptoms in male patients / 中华男科学杂志

<p><b>OBJECTIVE</b>To evaluate and compare the clinical efficacy and safety of the highly selective alpha receptor antagonist tamsulosin and its combination with the M receptor antagonist tolterodine in the treatment of refractory lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia (BPH).</p><p><b>METHODS</b>We included in this study 184 BPH patients with refractory LUTS with the disease course of 4 weeks to 2 years, whose LUTS were not alleviated after a week's treatment with tamsulosin. The patients were randomly divided into Groups A and B, the former (n=89) treated with tamsulosin at 0.2 mg qd and the latter (n=95) given tolterodine at 2 mg bid in addition to tamsulosin medication, both for 4 weeks. Scores on IPSS, QOL and Qmax were obtained before and after the treatment, and the improvement of LUTS evaluated after the medication.</p><p><b>RESULTS</b>The tamsulosin group showed no significant differences before and after the treatment in the scores on IPSS (13.23 +/- 4.39 vs. 12.21 +/- 4.07), QOL (4.23 +/- 1.27 vs 3.53 +/- 0.95) and Qmax ([12.3 +/- 8.39] ml/s vs. [14.1 +/- 8.62] mls) (P > 0.05), while the combination group exhibited significantly higher scores on IPSS and QOL and lower score on Qmax after the medication than before it (IPSS: 14.45 +/- 5.31 vs. 6.56 +/- 2.03, P < 0.05; QOL: 4.45 +/- 0.79 vs. 2.34 +/- 0.73, P < 0.05; Qmax: [11.4 +/- 9.21] ml/s vs. [15.5 +/- 8.35] ml/s, P < 0.01). No severe complications were found in any of the cases.</p><p><b>CONCLUSION</b>Combination of tamsulosin and tolterodine can significantly alleviate refractory LUTS and improve QOL without causing serious adverse events in BPH patients.</p>

Experimental study on the new significant function domains of KCHIP1 protein / 生理学报

Human K(v) channel interacting protein 1 (KCHIP1) is a new member of the neural calcium binding protein superfamily. Theoretically KCHIP1 has several calcium binding domains and two myristoylation sites. In this study, we demonstrated that the calcium binding domains and myristoylation sites were functional. The first, through running SDS-PAGE gel, we testified its ability of binding Ca(2+) with obvious discrepancy of the electrophoresis migrating rate after binding Ca(2+). Then, through the techniques of fused green fluorescence protein and site-directed mutagenesis, we demonstrated that wild type KCHIP1 protein accumulated in the secretory vesicles of Golgi body. In contrast, its two mutated forms without myristoylation sites accumulated throughout the whole cytoplasm. These observations indicate that KCHIP1 protein has a myristoylation motif mediating the interaction between KCHIP1 protein and membrane.

Purification and properties of Bacillus subtilis SA-22 endo-1, 4-beta-D-mannanase / 生物工程学报

beta-mannanase (EC 3.2.1.78) from Bacillus subtilis SA-22 was purified successively by ammonium sulfate precipitation, hydroxyapatite chromatography, Sephadex G-75 gel filtration and DEAE-52 anion-exchange chromatography. Through these steps, the enzyme was concentrated 30.75-fold with a recovery rate of 23.43%, with a specific activity of 34780.56 u/mg. Molecular weight of the enzyme was determined to be 38 kD by SDS-PAGE and 34 kD by gel filtration. The results revealed that the optimal pH value for the enzyme was 6.5 and the optimal temperature was 70 degrees C. The enzyme is stable between pH 5 to 10. The enzyme remained most of its activity after a treatment of 4 h at 50 degrees C, but lost 25% of activity at 60 degrees C for 4 h, lost 50% of activity at 70 degrees C for 3 h. The enzyme activity was strongly inhibited by Hg2+. The Michaelis constants (Km) were measured as 11.30 mg/mL for locust bean gum and 4.76 mg/mL for konjac powder, while Vmax for these two polysaccharides were 188.68 (micromol x mL(-1) x min(-1)) and 114.94 (micromol x mL(-1) x min(-1)), respectively.

Studies on purification of methamidophos monoclonal antibodies and comparative immunoactivity of purified antibodies / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To purify Methamidophos (Met) monoclonal antibodies with two methods and compare immune activity of purified antibodies.</p><p><b>METHOD</b>Caprylic acid ammonium sulphate precipition (CAASP) method and Sepharose protein-A (SPA) affinity chromatography method were used to purify Met monoclonal antibodies, UV spectrum scanning was used to determine protein content and recovery of purified antibodies, sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) was used to analyze the purity of purified antibodies, and enzyme-linked immunosorbent assay (ELISA) was used to determine immune activity of purified antibodies.</p><p><b>RESULTS</b>Antibody protein content and recovery rate with CAASP method were 7.62 mg/mL and 8.05% respectively, antibody protein content and recovery rate with SPA method were 6.45 mg/mL and 5.52% respectively. Purity of antibodies purified by SPA method was higher than that by CAASP method. The half-maximal inhibition concentration (IC50) of antibodies purified by SPA to Met was 181.26 microg/mL, and the linear working range and the limit of quantification (LOD) were 2.43-3896.01 microg/mL and 1.03 microg/mL, respectively. The IC50 of antibodies purified by CAASP to Met was 352.82 microg/mL, and the linear working range and LOD were 10.91-11412.29 microg/mL and 3.42 microg/mL, respectively.</p><p><b>CONCLUSION</b>Antibodies purified by SPA method are better than those by CAASP method, and Met monoclonal antibodies purified by SPA method can be used to prepare gold-labelled testing paper for analyzing Met residue in vegetable and drink water.</p>

Expression of Fas, FasL, and NF-kappa B in the process of osteoclast-like cell apoptosis effected by sodium fluoride / 中国医学科学院学报

<p><b>OBJECTIVE</b>To detect the changes in the expression of apoptosis signals: Fas, FasL and NF-kappa B in the process of osteoclast-like cell (OLC) apoptosis effected by sodium fluoride.</p><p><b>METHODS</b>After co-culture of osteoclast-like cells with 0, 5, 10 and 15 mg/L sodium fluoride, Fas, FasL and NF-kappa B antibody expressions were detected by immune-histochemistry.</p><p><b>RESULTS</b>The expression of Fas and FasL increased with the concentration of the sodium fluoride, however the expression of NF-kappa B decreased with the concentration of sodium fluoride.</p><p><b>CONCLUSION</b>In the process of OLC apoptosis induced by sodium fluoride, the expression of Fas and FasL increased, and that of NF-kappa B decreased with the concentration of sodium fluoride respectively, and the changes of the expression present a dose-dependent pattern.</p>