Study on adsorption of ten injectable drugs by eight kinds of disposable filter membranes for infusion apparatus / 中国药学杂志

OBJECTIVE: To investigate the absorbability of 8 kinds of disposable filter membranes for infusion apparatus to 10 injectable drugs, thus to provide information for clinical medication. METHODS: Each drug was separately dissolved in 250 mL 5% dextrose solution. Samples of drug solutions were collected before and after being filtered by the membranes. These samples were analyzed by HPLC-MS/MS methods. RESULTS: The 8 kinds of membranes had different adsorbabilities to the 10 injectable drugs. CN-CA membrane (CN-CA) and CN-CA Enhance membrane (CN-CA-E) adsorbed more drugs than other membranes (P<0.05). The average adsorption of PES membrane, NL-B membrane and ION membrane to the 10 drugs were lower than 1%. PP membrane and NL membrane to the 10 drugs were lower than 1.5%. CONCLUSION: PES membrane, ION membrane and NL-B membrane have lower adsorbabilityies than other membranes, thus may have little influence on medical treatment. They may be suitable for clinical application. Copyright 2012 by the Chinese Pharmaceutical Association.

Establishment and implementation of disease oriented integrated curriculum system for stomatology / 中华医学教育探索杂志

The traditional discipline-centered curriculum design can neither keep up with developments of modern medical science nor reach requirements of the education reform in the new century.Since 2011,College of Stomatology in School of Medicine in Shanghai Jiao Tong University had developed ‘ disease oriented integrated curriculum system reform’ for students of long-term stomatology education.In view of the problems existing in the original curriculum system,the integrated curriculum system was set up by coalescing clinical medicine curriculum according to the related systems and oral medicine curriculum according to the developmental rules of diseases.Lectures were combined with discussion classes in the reform and performance appraisal system was changed from simplex judgments into comprehensive evaluations.At last,further considerations of promoting the reform based on the practice were proposed.

Comparison of the therapeutic effects of PTBD and PTBS in treatment of malignant obstructive jaundice / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To summarize and compare the short-term and long-term clinical efficacy of percutaneous transhepatic biliary drainage (PTBD) and percutaneous transhepatic biliary stent (PTBS) in the treatment of malignant obstructive jaundice.</p><p><b>METHODS</b>210 cases of malignant obstructive jaundice underwent interventional therapy, of which 161 cases of drainage catheters placement and 49 cases of metallic stent implantation. Follow-up information was obtained through telephone review or check-up records.</p><p><b>RESULTS</b>The technical success rate of technique was 100%. At 3 - 5 days after treatment, the serum total bilirubin in 15 metallic stent-treated patients was decreased by (178.04 +/- 42.32) micromol/L, and direct bilirubin by (83.97 +/- 23.63) micromol/L. Compared with those of 28 cases treated with drainage catheters: (95.67 +/- 34.28) micromol/L and (49.84 +/- 28.21) micromol/L, there were statistically significant differences between the two groups (P = 0.017 and P = 0.035). At 6 - 9 days after treatment, the serum total bilirubin in 28 cases of metallic stent group was decreased by (188.22 +/- 79.90) micromol/L, and that in 126 cases of drainage catheter group decreased by (141.39 +/- 65.32) micromol/L. The difference was statistically significant (P = 0.014). But the decline value of direct bilirubin had no significant difference. The median patency period and the median survival time of the drainage catheter group were 60 and 148 days, respectively, those of metallic stent group were 197 days and 245 days. There were statistically significant differences between the two groups (P < 0.05).</p><p><b>CONCLUSION</b>The results of this study indicate that the short-term and long-term efficacies of metallic stent implantation are better than those of catheter drainage technique.</p>

Improving phytase expression by increasing the gene copy number of appA-m in Pichia pastoris / 生物工程学报

In order to improve the fermentation potency of phytase in recombinant host and decrease the production cost, the pichia expression vector pGAPZalpha-A was modified by introduction of an AOX1 promoter from vector pPIC9 and the resulted vector pAOXZalpha is an methanol induced vector. After that, a phytase gene appA-m was cloned into pAOXZalpha to construct the recombinant vector pAOXZalpha-appA-m. The recombinant Pichia pastoris 74#, which already contains one copy of appA-m and its fermentation potency exceeded 7.5 x 10(6) IU/mL, was used as the host strain for the transformation of pAOXZalpha-appA-m. The Pichia pastoris transformants were gained by electroporation. PCR results indicated that the appA-m expression box has integrated into the genome of Pichia pastoris and the original construction of phytase gene has not changed. SDS-PAGE analysis revealed that phytase was overexpressed and secreted into the medium supernatant. Recombinants with high expression level were screened and used for fermentation. In 5L fermentor, the expression level of phytase protein achieved 4 mg/mL and the phytase activity (fermentation potency) exceeded 1.2 x 10(7) IU/mL, which was about 1.6-fold compared with that of the host strain 74#. Moreover, the improved recombinant Pichia pastoris is excellent at expression stability and heredity stability.

Improvement of the thermostability of xylanase by N-terminus replacement / 生物工程学报

The hybrid xylanase TB was constructed by the substitution of the N-terminus segment of the Streptomyces olivaceoviridis xylanase XYNB with corresponding region of Thermomonosporafusca xylanase TfxA. The hybrid gene tb, encoding the TB, was correctly expressed in Escherichia coli BL21 and Pichia pastoris GS115. TB was purified and its enzymatic properties were determined. The results revealed that the optimal temperature and optimal pH of TB were at 70 degrees C and 6.0, which have been obviously improved compared with those of XYNB. The thermostability of TB were all about six-fold of XYNB's after incubating the properly diluted enzyme solutions at 80 degrees C and 90 degrees C for 3min, respectively. The pH stability of TB was 5 to approximately 9, which was narrower than that of XYNB. Still, TB remains a high specific activity as XYNB does. Analysis of a homology modeling and sequence similarity were used to reveal the factors influencing the enzymatic properties of TB and the discussion for the relationship between structure and function of xylanase was given.

Hydrophobic interaction between beta-sheet B1 and B2 in xylanase XYNB influencing the enzyme thermostability / 生物工程学报

A homology modeling of xylanase XYNB from Streptomyces olivaceoviridis A1 was made by Swiss-Model. The hydrophobic Interaction between beta-sheet B1 and B2 in the tertiary structure model of XYNB was compared with other thermophilic xylanase. A T11Y mutation was introduced in XYNB by site-dirrected mutagenesis to improve the thermostability of the enzyme. The XYNB and mutant xylanase (XYNB') expressed in Pichia pastoris were purified and their enzymatic properties were determined. The result revealed that the thermostability of XYNB' was obviously higher than that of XYNB. The optimal temperature of XYNB' for its activity was 60 degrees C, similar to XYNB. But, compare to XYNB, the optimal pH value, the Km value and the specific activity of XYNB' had also been changed. The research results suggested that the aromatic interaction between beta-sheet B1 and B2 in xylanase should increase enzyme thermostability. The mutant xylanase XYNB' is a good material for further research in the relationship between structure and function of xylanase.