Application of CRISPR in evolution analysis, detecting and typing, virulence and antibiotic resistance regulation in food-borne pathogens / 生物工程学报

Clustered regularly interspaced short palindromic repeats (CRISPR) and its associated protein gene system can limit the horizontal gene transfer, thereby effectively preventing the invasion of foreign gene elements such as bacteriophages. CRISPR arrays of different bacteria are diverse. Based on the differences in the CRISPR system, this review summarizes the application of CRISPR in food-borne pathogen evolution analysis, detection and typing, virulence and antibiotic resistance in recent years. We also address bacterial detection typing method developed based on the characteristics of CRISPR arrays and the association of CRISPR with virulence and drug resistance of food-borne pathogens. The shortcomings of CRISPR in evolution, detection and typing, virulence and resistance applications are analyzed. In addition, we suggest standardizing CRISPR typing methods, improving and expanding the CRISPR database of pathogenic bacteria, and further exploring the co-evolution relationship between phages and bacteria, to provide references for further exploration of CRISPR functions.

One case report of overseas imported quartan malaria / 中国血吸虫病防治杂志

This paper reports one case of overseas imported quartan malaria and the diagnosis and treatment process. By using dihydroartemisinin combined with piperaquine,the treatment results are satisfactory.

Development of sustained release tablet of tamoxifen citrate and its in vitro release profile / 北京大学学报(医学版)

Objective: To reduce the frequency of administration of tamoxifen citrate so as to improve its bioavailability and patients’ compliance. Methods: HPMC K4M was employed as major retarded release controller. The wetting granulation and directly compressing method was used to produce the sustained release tablet. Then the in vitro release profile was applied as main criteria to evaluate six formulations according to the variation of HPMC K4M amount. The concentration of tamoxifen citrate was measured by UV spectrometry. Finally the releasing characteristics of sustained release and conventional tablets were compared to clarify the sustained effect of the former. Result: At 278 nm there was no interaction between tamoxifen citrate and the recipients so that it was adopted as the wavelength of determination. The recovery efficiency of this method ranged from 95%-105%. The final formulation could release 86.40% of its loading amount in 12 h and its releasing profile fitted the Zero order equation well. The percentages of accumulative release in 1 h were 76.81% and 7.08% for sustained release tablet and conventional tablet respectively. Conclusion: The sustained release tablet of tamoxifen citrate could demonstrate a continuous and stable releasing profile and last for over 12 h. It has significant retarded effect in comparison with the conventional one and could be a new choice of regimen in its clinical application.