Aim To construct 3 D structure model of cardiac Cav1.2 channel and check its accuracy and re-liability.Methods Homology model of Cav1.2 chan-nel α1 subunit was constructed using SWISS-MODEL server.The model was submitted to an online testing server built by University of California and scored by it.The binding of Cav1.2 channel with blocker or drug was simulated by MOE software molecular docking pro-gram to check the model′s accuracy and reliability.Re-sults Both the target sequence Cav1.2 α1 C and the template sequence Cav1.1 α1 S searched by SWISS-MODEL server belonged to L-type Ca2+channel.Since the homology was 7 1.5% revealed by sequence align-ment,homology modeling was performed using automa-ted mode.L-type Ca2+ channel blockers Verapamil, Nifedipine and Diltiazem could bind to the 3 D structure model of Cav1.2 channel,while sodium channel bloc-ker TTX could not.Furthermore,active ingredient of traditional Chinese drug Praeruptorin A and Berberine could also bind to the 3D structure model of Cav1.2 channel.Conclusion The 3 D structure model of Cav1.2 channel was constructed successfully,which provides reliable materials for further studies and estab-lishes the foundation for the application of homology modeling in the study of 3 D structure prediction of ion channels.

Objective To investigate a method for the purification of the N?terminal peptide fragment(NT)of the myocardial calcium channel Cav1.2,and characterize its interaction with calmodulin(CaM). Methods EscherichiacoliBL?21 cells were transformed with plasmid pGEX?6p?3/NT harboring the NT?GST fusion gene. The cells harboring pGEX?6p?3/NT were cultured and protein expression was induced with isopropyl?β?D?thiogalactoside(IPTG). Then,the GST?NT fusion protein was purified by using glutathione Sepharose 4B(GS?4B)beads. GST was cleaved off with the PreScission protease,and SDS?PAGE was performed to detect the purity and relative molecular weight of the purified peptide. Further, GST pull?down assay was performed to characterize the interaction of the NT peptide with CaM. Results SDS?PAGE analysis showed that the NT peptide was successfully purified,with high purity. Results of the GST pull?down assay showed that the NT peptide could interact with CaM. Conclusion This study establishes a method for the purification of the NT peptide and lays the foundation for further research on the interaction partners and biological functions of NT.

Objective:To investigate the application value of digital X-ray radiotherapy and single photon emission computed tomography(SPECT)radionuclide bone imaging in the diagnosis of intertrochanteric fracture of femur.Methods:A total of 70 patients who were diagnosed as intertrochanteric fracture of femur in Shijiazhuang People's hospital from January 2017 to December 2020 were selected,and they were divided into study group and control group according to random number method,with 35 cases in each group.Digital X-ray radiography combined with SPECT radionuclide bone imaging was used in the study group,and digital X-ray radiography was used in the control group.And then,the accuracy of the diagnostic results between the two groups were compared.Results:The radiographic examination indicated that 31 cases(88.6%)of 35 cases in the study group were confirmed,and 24 cases(68.6%)of 35 cases in the control group were confirmed.The diagnostic accuracy rate of the study group was significantly higher than that of the control group,and the difference was statistically significant(x2=4.158,P<0.05).The preoperative imaging diagnosis indicated that diagnosed number of fracture blocks in the study group was(3.57±0.50),which was significantly higher than that(2.67±0.40)in the control group,and the difference of that between two groups was statistically significant(t=8.315,P<0.05).In the actual intraoperative examining for bone continuity,5 cases were continuity and 30 cases were non-continuity.In the bone stability,13 cases were stability and 22 cases were non-stability.The study group was closer to intraoperative bone continuity and bone stability,and the differences of them between two groups were statistically significant(x2=12.857,4.644,P<0.05),respectively.Conclusion:The combination of digital X-ray radiography and SPECT radionuclide bone imaging has higher diagnostic value for intertrochanteric fracture of femur,which can provide important reference for clinical diagnosis.

Objective To construct a CaME141G fusion protein-expressing plasmid,and to express,purify,and identify the activity of the recombinant protein. Methods The 141st site of the wild type CaM,E (GAG),was mutated to G (GGG),using site-specific mutagenesis technology. Escherichia coli BL-21 was transformed with the mutant plasmid. The GST-CaME141G fusion protein was mass-cultured and induced for expression. Subsequently,the GST-CaME141G fusion protein was purified using GS-4B beads. PreScission protease was applied to remove the GST,the Bradford method used to determine the concentration of purified protein,and SDS-PAGE used to detect its relative molecular weight and purity. The GST pull-down assay was used to study the protein's biological activity. Results The CaME141G protein was successfully purified at a high concentration and purity. The protein could interact with PreIQ protein fragments from the myocardial CaV1. 2 calcium channel C terminal,in a CaME141G concentration-dependent manner. Therefore,CaME141G has the ability to bind with the CaV1. 2 calcium channel. Conclusion This study successfully constructed a CaME141G fusion protein-expressing plasmid and purified the CaME141G protein. This lays a foundation for regulating the function of CaM mutations in the myocardial CaV1. 2 calcium channel,and for the study of its relationship with diseases of the cardiovascular system.

Objective To investigate the effect of tyrosine kinase inhibitor(TKI)on radioiodine-refractory differentiated thyroid carcinoma(RAI-rDTC).Methods Literature related to RAI-rDTC was retrieved from Wanfang Data,CNKI,VIP,PubMed,Cochrane,EmBase and Medline databases until December 31,2021.Literature quality and experimental bias were referred to the Cochrane quality risk assessment table,and Meta-analysis was performed using RevMan 5.3 software.Results A total of 1384 patients were included in 6 studies.The results of Meta-analysis showed that the median progress free survive(HR=0.30,95%CI:0.18-0.50,P<0.00001)and overall survival(HR=0.70,95%CI:0.57-0.88,P=0.002)in treatment group were significantly longer than those in control group.There was no significant difference in complete response between two groups(RR=3.31,95%CI:0.41-26.89,P=0.26).The partial response in treatment group was significantly higher than that in control group(RR=15.97,95%CI:3.48-73.17,P=0.0004).The incidence of TKI-related adverse reactions above grade 3 in treatment group was significantly higher than that in control group(RR=2.91,95%CI:1.70-4.96,P<0.0001).Conclusion TKI can significantly prolong progress free survive and overall survival in patients with RAI-rDTC,but there are still many adverse reactions.It is necessary to comprehensively evaluate the health status of patients before medication.