A trimeric RBD protein as a booster vaccine enhanced the humoral response and broad neutralization against SARS-CoV-2 in mice / 中华微生物学和免疫学杂志

Objective:To investigate the efficacy of a SARS-CoV-2 recombinant protein vaccine as a booster dose.Methods:A new immunogen, namely RBD-sc-trimer, was designed by tandem repeating of single receptor binding domain (RBD) of SARS-CoV-2 spike (S) protein to mimic the trimeric form of RBD presented by the virus. The RBD-sc-trimer protein was expressed as a His-tagged fusion protein using a baculovirus expression system and purified by nickel affinity column. The purified protein was identified by Western blot. Its in vitro binding activity to human angiotensin converting enzyme 2 (hACE2) was analyzed by ELISA. The immunogenicity of RBD-sc-trimer as well as RBD proteins of other forms including RBD dimer (RBD-Fc), RBD monomer (RBD) and S protein trimer (S trimer) as a booster dose was evaluated in BALB/c mice. Results:In terms of both binding and neutralizing antibodies against SARS-CoV-2, RBD-sc-trimer showed an immunogenicity that was superior to that of RBD-Fc and RBD and close to the level of S trimer. The antibody response induced by RBD-sc-trimer was characterized as Th1-biased. Moreover, it displayed a stronger cross-neutralization activity against SARS-CoV-2 Beta, Delta and Omicron variants. The titer of neutralizing antibody against Omicron induced by RBD-sc-trimer only decreased by 9.1 folds relative to the prototype strain, while the antibody response induced by RBD-Fc and S trimer decreased by 68.4 and 70.8 folds, respectively.Conclusions:The recombinant protein, RBD-sc-trimer, which was capable of eliciting stronger humoral response in mice as a booster dose and showed the superiority in raising cross-reactive antibodies against SARS-CoV-2 variants over non-trimeric RBD forms, should be considered as an optimal immunogen for the development of more effective SARS-CoV-2 vaccines.

Clinical significance of TrACP in diagnosis and prediction of bone metastasis in prostate cancer / 局解手术学杂志

Objective To study the changes of tartrate resistant acid phosphatase in the serum of patients with bone metastasis in pros-tate cancer,and to explore its clinical significance for bone metastasis diagnosis and prediction of prostate cancer. Methods Seventy-eight cases of prostate cancer and 40 cases of benign prostatic hyperplasia patients as the research object,at the same time,40 healthy young men as controls,were divided into the group of patients with prostate cancer bone metastases (group A,n=41),prostate cancer patients with no bone metastasis group (group B,n=37),benign prostatic hyperplasia patient group (group C,n=40),healthy control group (group D,n=40). Determination of serum TrACP levels in patients with the immunoassay using double antibody sandwich ELISA,combined with pathologi-cal grade,Gleason score,PSA,ALP and ALT were statistically analyzed. Results The serum TrACP concentration in patients with bone me-tastasis significantly increased,with significant difference compared with the other groups. The concentration of serum TrACP and PSA levels showed a positive correlation. The area under the ROC curve ( AUC) was higher than that in ALT,and the ROC curve of cross TrACP and PSA,suggesting that high value in the diagnosis of bone metastasis. Conclusion The detection of TrACP has directly diagnosis and predic-tive value for prostate cancer with bone metastasis,the serum TrACP content monitoring in patients with prostate cancer has valuable clinical significance in understanding the growth progression status of prostate cancer,judgment and prediction of bone metastases.

Application of virtual reality simulators and surgical demonstration in laparoscopic operation training / 中华医学教育探索杂志

Virtual reality simulators and surgical demonstration were used in laparoscopic teaching combining teacher' guiding with students' practice to improve the teaching effectiveness hecause of the limitations of the traditional apprenticeship teaching methods.The new method was applied for 2 cycles and for 6 weeks.The results showed that the teaching methods of virtual reality simulators combined with surgical demonstration can significantly improve the effectiveness of laparoscopic teaching and shorten the initial learning curve,therefore it is worth promoting in laparoscopic operation training and teaching.

Study on the teaching of modular transurethral enucleation of the prostate operation / 中华医学教育探索杂志

To establish a new kind of minimally invasive surgical model of transurethral prostate enucleation operation and method that makes the operation easier and reduces the surgeon learning curve.According to the order and the path of surgical operation,prostate enucleation operation is split into 4 different modules named as A,B,C,D,and it is called modular transurethral enucleation of the prostate.The operation mode optimizes the process of operation design, modularizes the contents of surgical procedures,processes,and reduces the difficulty of the operation,and simplifies the surgical procedure,which can effectively shorten the operation time and make it easy for beginners to carry out and control the procedure.It has a great popularization value.

Screening of mimic epitope for MUC1 based on prediction of the antigenic epitope / 重庆医科大学学报

Objective:To predict the B cell epitope for MUC1 antigene and screen the mimic epitope of MUC1 from random phage dispay peptide library. Methods:In order to predict the B cell epitope for MUC1 antigen,the secondary structure and antigenicity was analysed with various methods. The purified Ma695 Ab was used to screen in phage random 12 peptide library. The positive clones were identified by sandwich ELISA and competitive inhibiton assay. Results:17 distinct antigenic epitope regions in MUC1 were identified by computation. 14 positive clones were acquired after 3 rounds of screening. Amino acid sequences deduced from DNA sequences showed four different sequences:KHYDPFHHRMPQ,QADTARSVALAG,VPSKPDLHVRSI and MTPIHYWNHNRV. The inhibitory assay showed that the 4 mimic epitope peptides displaying on the phage surface could effectively inhibit the combination of antibody with antigen and the inhibitory rates of each mimic epitope were 50% higher than that in the controls. Conclusion: Prediction of the B cell epitope for MUC1 can provide a basic clues for studies on structure and function of MUC1. The results indicated that KHYDPFHHRMPQ,QADTARSVALAG,VPSKPDLHVRSI and MTPIHYWNHNRV are the mimotopes which could mimic the epitope of MUC1.

Reversal effects of carvedilol on multidrug resistance in bladder cell lines / 中国癌症杂志

Purpose:To study the reversal effects on multidrug resistance in multidrug-resistent bladder cell lines BIU-87/ADM. Methods:The degree of drug-resistence was detected by MTTmethod; the concentration of ADM in cells BIU-87 and BIU-87/ADM was detected after the cells were treated by carvedilol and ADM. Results:Pretreatment by carvedilol increased the concentration of ADM in BIU-87/ADM cells, ,and the concentration was much higher than that in those cells treated by ADM only. Conclusions:Carvedilol can enhance the cytotoxic effect of ADM,and can reverse the multidrug resistance in bladder cancer lines BIU-87/ADM.

Antigenic epitopes analyses and expression of P-glycoprotein / 中国癌症杂志

Purpose:To study antigenic epitopes and expression of P glycoprotein.Methods:The secondary structure and surface properties of P glycoprotein was studied by many methods , designed a pair of primers to amplify DNA with PCR. The product was inserted into a pGEM T vector, sequenced and cloned into pGEX 2T vector, established a high expression recombinant vector named pGEX Pgp,which was transferred into DH5? and expressed , identified and purified. Results:Antigenic epitopes in extracellular fragment of P glycoprotein were identified in amino acid residues 82 115(I),741 760(IV) and 800 816(V). SDS PAGE analysis indicated that the expressed protein was about 30?10 3 (30 kD).Conclusions:High level expression of the target gene fragment was established for preparation of its antibody and biospanning its specific peptide using random phage library , which became the basis for the targeting treatment of MDR. [

Expression of TopoⅡ gene in human bladder cancer multidrug-resistant cells / 中国癌症杂志

Purpose:To study the expression of TopoⅡ gene in multidrug resistant cells of human bladder cancer. Methods:The degree of drug resistance was detected by MTT method ;the expression of TopoⅡ gene in cell lines BIU 87/ADM and BIU 87 was detected with reverse transcriptase polymerase chain reaction. Results:The cell lines BIU 87/ADM were 56.4 times more resistant to ADM than the cell lines BIU 87;the expression of TopoⅡ gene was poorly positive in BIU 87/ADM but strongly positive in BIU 87 cells. Conclusions: The decreased expression of TopoⅡ gene in BIU 87/ADM cells might contribute to the development of multidrug resistance of human bladder cancer.

Prediction of the B cell epitope for MUC1 antigen / 第三军医大学学报

Objective To predict the B cell epitope for MUC1 antigen. Methods The secondary structure and surface properties of MUC1, such as physical and chemical characters, hydrophilicity, antigenicity, were analyzed with various methods. Results Many distinct antigenic epitopes in MUC1 were identified by computation: 1-10, 24-54, 65-77, 84-91, 108-134, 140-156, 159-174, 179-196, 199-210, 220-233, 237-265, 270-299, 316-337, 351-362, 369-396, 411-420, and 445-502. Conclusion Prediction of the B cell epitope for MUC1 can provide a base for the studies of structure and function of MUC1, construction of its mutants, and selection of new expression forms of MUC1.

Expression of fused P-glycoprotein in E. coli DH5? / 第三军医大学学报

Objective To study the expression of the extracellular fragment of P glycoprotein in the bacteria. Methods According to the P glycoprotein antigen analyses and mdr1 gene structure, a couple of primers were designed to amplify the extracellular DNA fragment of the protein with PCR. The product was inserted into pGEM T vector followed by sequencing. The sequencing verified vectors were cloned into pGEX 2T to get a highly expression recombinant vector pGEX Pgp. The recombinant was transferred into E. coli DH5?, and its expression, identification and purification were studied. Results The highest level of recombinant expression was achieved at 4 h after IPTG induction. SDS PAGE analysis indicated that the expressed protein was about 30?10 3. Conclusion The target gene fragment expression at high level is established for the preparation of its antibody and biospanning of its specific peptide by using random phage library, founding a basis for the targeting treatment of multidrug resistance.