Toxicity detection of heat-labile enterotoxin in non-toxic mutant of Escherichia coli and investigation on its adjuvant effect of E.coli heat-labile enterotoxin / 中国人兽共患病学报

In the present study, the expression, purification, toxicity detection and the adjuvant effect of the heat-labile enterotoxin in non-toxic mutant mLT63 of Escherichia coli were investigated, in which the inductive expression was performed under optimal condition for inductive expression and the toxicity of the products obtained from inductive expression were tested for toxicity after being purified and concentrated with affinity chromatography. BALB/c mice were immunized orally with the mutant mLT63 associated with Helicobacter pylori (Hp) subunit vaccine UreB, Omp11. After immunization, the specific antibody levels in serum, extract from gastric tissues and fecal extract were determind by means of ELISA assay and the results were subjected to statistical analysis. It was demonstrated that the mutant mLT63 of heat-labile entrotoxin of E.coli constructed in our laboratory devoided of any toxic effect as revealed by the rabbit ileal loop assay, but its adjuvant effect could be demonstrated in the associated immunization of mice with Hp subunit vaccine UreB and Omp11.

Study and design of portable medical drop speed monitoring equipment / 医疗卫生装备

Objective To develop a portable medical drop speed monitoring equipment which can conveniently control the drop speed in infusion.Methods Taking the monolithic integrated circuit of 89C51 as a core,such units were designed as the master control unit,keyboard input system,drop speed detection,drop speed control,digital display,acousto-optics alarm circuit and electromotor drive.All circuit module units were connected in monolithic integrated circuit.The gathering data were transferred to monolithic integrated circuit in the form of electrical signals.After the operation,analysis and processing,monolithic integrated circuit transferred the data to demonstration module,electrical machinery and acousto-optics alarm circuit through the outlet.Results Automatically controlling the drop speed according to the difference of drop speed,this equipment can reach the required drop speed in 5~10s and maintain this speed with an error of 12 drops per minutes.Conclusion Portable medical drop speed monitoring equipment achieves the goal of the task and meets the clinical requirement.This equipment is worthy of popularizing.