ObjectiveTo construct human embryonic kidney cells (HEK293) modified with human preproenkephalin (hPPE) gene.MethodshPPE gene fragments were obtained from recombinant plasmid pcDNA3.1( + )/hPPE by using restriction endonuelease Hind Ⅲ and Not Ⅰ.Homologous recombination of lentivirus and hPPE gene was produced by using recombinant DNA technology.HEK293 cells were then transfected with the recombinant lentivirus vectors.The expression of hPPE gene in HEK293 cells was detected by Western blot.ResultsThe results of DNA sequencing indicated that the positive clone of recombinant lentivirus was completely consistent with sequencing of hPPE in Genebank.The titer of the concentrated virus was 2.07 × 108 TU/ml.GFP fluorescence was not seen in HEK293 cells transfected with the lentiviral vector under fluorescence microscope.A strong fluorescence was seen in HEK293 cells transfected with Ubc-GFP-L.V.empty viral vector.Positive expression of hPPE was demonstrated in HEK293 cells transfected with lentiviral vector by Western blot.Conclusion HEK293 cells modified with hPPE gene were successfully constructed and the target gene hPPE was stably expressed in HEK293 cells.

Aim To study the relationship between the vasodilatation effects of daidzein and M-receptor in the endothelial cell, extracellular Ca2+ and intracellular Ca2+.Methods Measurement of isometric force of rabbit thoracic aortae rings was performed. Results Dai(3～100 ?mol?L-1 ) significantly inhibited the contractive response of phenyleohrine dependent on intracellular Ca2+ release and extracellular Ca2+ inflow;a shift was produced to the right of the concentration-effect curve of KCl and the maximum response was depressed by Dai(10～100 ?mol?L~ -1 ); Dai(10,30,100 ?mol?L-1 ) enhanced the relaxing effect induced by acetylcholine in a concentration-dependent manner,but the relaxing effect was inhibited after using atropine to block the M-receptor. Conclusion The relaxing effect of Dai was related to the inhibition of the receptor-mediated Ca2+ -influx and Ca2+-release;Dai induced direct relaxing effect by activating the M-receptor in the endothelium and releasing EDRF, which was similar to ACh, and this effect was endothelium-dependent.

Objective To investigate the effects of selenium and iodine deficiency on the contractibility of rat thoracic aorta and probe into its mechanisms.Methods Isolated vascular methods were used to study the effects in different groups.Results The contraction of rat thoracic aorta of the groups with selenium and iodine deficiency was less than that of the normals(P(0.05));sodium selenite(0.1mol/L) had no effect on rat aortic contraction,but was significantly synergic with the contraction induced by KCl combined with NE(P

Objective To evaluate the release of leucine-enkephalin (L-EK) in the cerebrospinal fluid induced by intrathecal human embryonic kidney (HEK293) cells modified with human preproenkephalin (hPPE)gene and the analgesic efficacy of L-EK for bone cancer pain.Methods Forty CIBP female Sprague-Dawley rats were randomized into transplantation (CIBP+ hPPE/HEK293,n =20) and control (CIBP + HEK293,n =20)groups using a random number table.At 1 day before inoculation of cancer cells (T1,baseline) and 8,15,21,25,32 and 35 days after inoculation (T2-7),thermal paw withdrawal latency (TWL) was measured,and the number of licking/biting the claw on the transplantated side and degree of hindlimb limping during free activities were recorded.After observation at T4,10 rats were chosen from each group and sacrificed and the cerebrospinal fluid of rats was collected in an ice bath for detection of hPPE expression using radioimmunoassay.Results Compared with control group,TWL was significantly prolonged,the concentration of L-EK in the cerebrospinal fluid was increased,and the number of licking/biting the claw on the transplantated side and degree of hindlimb limping during free activities were decreased at T4-7 in transplantation group.Conclusion Intrathecal HEK293 cells modified with hPPE gene can continuously secrete L-EK and mitigate bone cancer pain.

Naringin is mainly present in Rutaceae Citrus Pomelo,grapefruit,lime,and its variants of the peel and fruit,which belongs to dihydrogen flavonoids.Studies have shown that naringin has anti-type 1 and type 2 diabetes pharmacological effects,the mechanism of action by inhibiting diabetes-related oxidative stress injury,inflammation,abnormal metabolism of glucose,and other aspects,while a certain degree of delay in diabetes complications (including diabetic cardiomyopathy,diabetic nephropathy,diabetic retinopathy,and diabetic neuropathy).The mechanism of naringin on the mechanism of diabetes mellitus and its complications was studied in order to provide the basis for the development of antidiabetic drug.

Objective:To evaluate the operation of urinary iodine external quality control network in Shaanxi Province in 2020, to know the urinary iodine detection capabilities of iodine deficiency disorders (IDD) laboratories in Shaanxi Province, so as to ensure the technical support for epidemiological surveillance and control of IDD.Methods:In 2020, a total of 118 IDD laboratories in Shaanxi Province participated in the external quality control assessment, and the two concentrations of urinary iodine quality control samples were measured by As 3+-Ce 4+ catalytic spectrophotometry. The testing results of urinary iodine were statistically analyzed with standard value ± uncertainty and Z-ratio scoring methods. Results:All the 118 laboratories participating in the external quality control assessment of urinary iodine in the province had feedback the assessment results. The standard value ± uncertainty method was used for evaluation, the test results of 118 laboratories in the province were all within the uncertainty range, and all were qualified. The Z-ratio scoring method was used for evaluation, there were two county level laboratories with an inter-laboratory |Z| score≥3, and the evaluation results of other laboratories were all qualified, with a qualified rate of 98.31% (116/118). The results of the two evaluation methods were basically consistent.Conclusions:After years of external quality control network operation, the urinary iodine detection capability of laboratories at all levels in Shaanxi Province is stable and reliable, and most laboratories have passed the ability verification. It is suggested that individual laboratory should strengthen internal quality control and improve detection capabilities to lay a solid foundation for monitoring and prevention of IDD.