Effect of dimethyl fumarate on rats with chronic pancreatitis

OBJECTIVE@#To discuss the effect of dimethyl fumarate (DMF) on rats with l-arginine induced chronic pancreatitis (CP).@*METHODS@#Male Wistar rats were given DMF treatment (25 mg/kg) by oral lavage method; then Wistar rats were given the intraperitoneal injection of l-arginine for 5 times (250 mg/100 kg, twice per time, each interval of 1 h) for building of CP model. Rats were divided into control group, CP group, DMF group and CP + DMF group. Rats in CP + DMF group were given the oral intragastric administration of DMF (25 mg/kg), while rats in control group and CP group were given the equal volume of normal saline. The weight of rats was evaluated and the intraperitoneal glucose tolerance test was performed (IPGTT, 2 g/kg). The islet of rats was isolated and then flow cytometry was employed to evaluate the quality and activity of islets. Meanwhile, the histology of non-endocrine tissues and levels of myeloperoxidase (MPO) and malondialdehyde (MDA) were detected.@*RESULTS@#Compared with control group, the weight of rats in CP group was significantly reduced at week 2, 4 and 6; the blood glucose significantly increased, AUC increased, the histopathological scores of pancreatic atrophy, acinar injury, edema and cellular infiltration increased, levels of MDA and MPO increased, the islet equivalent and islet activity decreased at 0, 30, 60, 120 and 180 min. Compared with CP group, the weight of rats in CP + DMF group significantly increased at week 2, 4 and 6; the blood glucose significantly decreased, AUC decreased, the histopathological scores of pancreatic atrophy, acinar injury, edema and cellular infiltration decreased, levels of MDA and MPO decreased, the islet equivalent and islet activity increased at 0, 30, 60, 120 and 180 min.@*CONCLUSIONS@#DMF treatment can improve CP induced by l-arginine and islet function in rats.

Effect of dimethyl fumarate on rats with chronic pancreatitis

Objective: To discuss the effect of dimethyl fumarate (DMF) on rats with l-arginine induced chronic pancreatitis (CP). Methods: Male Wistar rats were given DMF treatment (25 mg/kg) by oral lavage method; then Wistar rats were given the intraperitoneal injection of l-arginine for 5 times (250 mg/100 kg, twice per time, each interval of 1 h) for building of CP model. Rats were divided into control group, CP group, DMF group and CP + DMF group. Rats in CP + DMF group were given the oral intragastric administration of DMF (25 mg/kg), while rats in control group and CP group were given the equal volume of normal saline. The weight of rats was evaluated and the intraperitoneal glucose tolerance test was performed (IPGTT, 2 g/kg). The islet of rats was isolated and then flow cytometry was employed to evaluate the quality and activity of islets. Meanwhile, the histology of non-endocrine tissues and levels of myeloperoxidase (MPO) and malondialdehyde (MDA) were detected. Results: Compared with control group, the weight of rats in CP group was significantly reduced at week 2, 4 and 6; the blood glucose significantly increased, AUC increased, the histopathological scores of pancreatic atrophy, acinar injury, edema and cellular infiltration increased, levels of MDA and MPO increased, the islet equivalent and islet activity decreased at 0, 30, 60, 120 and 180 min. Compared with CP group, the weight of rats in CP + DMF group significantly increased at week 2, 4 and 6; the blood glucose significantly decreased, AUC decreased, the histopathological scores of pancreatic atrophy, acinar injury, edema and cellular infiltration decreased, levels of MDA and MPO decreased, the islet equivalent and islet activity increased at 0, 30, 60, 120 and 180 min. Conclusions: DMF treatment can improve CP induced by l-arginine and islet function in rats.

Development of the chip system for measurement of red blood cell rheology / 中国医疗器械杂志

We have developed a novel silicon microchannel system for the research of the red blood cell rheology and deformation. Recurring to many kinds of information technologies and advanced test means such as the electronic microscope, the image acquisition system and the computer processing system and by using the up-to-date Micro Electro Mechanical System (MEMS) technology, a new measuring system of red bood cell deformation is designed based on the chip and a model using the silicon microchannel to simulate capillary vessel network. It provides a real-time collection and anaysis of data which include image, speed, flow parameter, and so on. It provides printing, storage of the analysis results and patients' database management.

Study on construct and expression of synthetic genes encoding spider dragline silk in Escherichia coli / 生物工程学报

Dragline spider silk produced from Nephilia clavipes major ampullate is a natural fibrous protein with specific mechanical properties such as high tensile strength and elasticity. Synthetic gene monomer encoding recombinant spider silk protein, based on the known repetitive protein sequence and partial cDNA sequence of dragline silk, was constructed and expressed. DNA monomer sequences were multimerized to encode high molecular weight synthetic spider silks using a "head-to-tail" construction strategy. Multimer was cloned into pET30a(+), a prokaryotic high potency expression vector, and induced with IPTG. The protein from 8-unit repeat was produced in Escherichia coli at levels up to 20 mg/L. The protein was easily purified with high recovery by using an metal ion affinity chromatography and purity was over 90%. The results of SDS-PAGE and Western blot suggested that the mass of the expression product was about 37 kD. This value and amino acid analysis were consistent with those of theoretic calculation.

FERMENTATION CONDITIONS OF SOYMILK-CLOTTING ENZYME PRODUCTION BY BACILLUS SP.AND STUDIES ON THE PROPERTIES OF THE ENZYM E / 微生物学通报

The optimum condition of shaking-flask p roducing enzyme were the tempe rature 26℃,initial pH 6 4,fermentation period 19 hours,medium volume 15mL m e dium/300mL Flask.soymilk-clotting enzyme was obtained from ammonium sulfate p r ecipitation.The optimum temperature and pH for the soymilk-clotting activity wa s 70℃and 5 8.The enzyme was easy to lose activity in acid or alkaline circumst a nce.About 60% of the original activity remained after 1 hour at 60℃.Ca 2+ ,Fe 2+ , Mg 2+ ,Na +increased the clotting activity,whereas Zn 2+ ,Al 3+ ca use inhibition.