1.Construction of a recombinant Neisseria gonorrhoeae strain with rmp gene deletion and study on the bactericidal activities of its antibodies
Guocai LI ; Rushan XIE ; Yanli MAO ; Shuangxi LIU ; Hongmei JIAO ; Hongju CHEN ; Hua YAN ; Mingchun JI
Chinese Journal of Microbiology and Immunology 2013;(8):578-582
Objective To study the role of the outer membrane protein Rmp of Neisseria gonor-rhoeae strain in immunosuppression and the strategy of eliminating it .Methods The rmp gene of Neisseria gonorrhoeae strain was amplified by PCR and inserted into pMD 19-T vector .The recombinant vector pMD 19△rmp∷Kan containing Kan and the 5′-and 3′-flanking regions of rmp (△rmp∷Kan) was constructed by replacing 200 nucleotide residues of pMD 19-rmp with kanamycin resistance gene Kan and transformed into Neisseria gonorrhoeae WHO-A strain.PCR and Western blot assay were used to screen and identify the re-combinant mutant strains that could not express Rmp .Mice were immunized with mutant strains and bacteri-cidal activities of the immune sera were detected by antibody-mediated complement-dependent cytotoxicity assay.Results The mutant strains that could not encode Rmp were successfully constructed .Antibodies in-duced by mutant strains showed stronger bactericidal activity against Neisseria gonorrhoeae in comparison with those induced by wild strains .Conclusion The recombinant Neisseria gonorrhoeae strain with rmp gene de-letion might eliminate the immunosuppressive effects of Rmp expressed in wild gonococcal strains , which provides a reference for further development of novel live attenuated whole-cell vaccines of Neisseria gonor-rhoeae.
2.EGFR siRNA inhibits activation of astrocytes derived from rats through blockade of STAT3 phosphorylation
Hong QIAN ; Lijing LIU ; Yanchun LI ; Ming XIE ; Heng WU ; Shuangxi LIU ; Bin WU
Chinese Pharmacological Bulletin 2016;(2):216-222
Aim To observe the expression of epider-mal growth factor receptor ( EGFR) in cerebral tissues around hematomas after intracerebral hemorrhage, and explore the effects of EGFR on activation of astrocytes derived from rats and the involved mechanisms. Meth-ods The specimens of cerebral tissues around hemo-tomas after intracerebral hemorrhage undergoing hemo-tomas removal operation were collected and then divid-ed into 4 groups according to the time of intracerebral hemorrhage: <1 d, 1 ~5 d, 6 ~10 d and >10 d groups. Each group included 20 cases. At the same time, 20 dropped brain tissues distant to hemorrhage in the operative process were collected as control group. Immunohistostaining and Western blot were used to measure the expression of EGFR. After isolation and culturing, the astrocytes of rat cortex were treated with culture solution ( control group) , CNTF that was used to activate astrocytes, scramble siRNA + CNTF and EGFR siRNA +CNTF for 24h, respectively. The ex-pression of glial fibrillary acidic protein ( GFAP) mR-NA was detected through fluorescence real-time quanti-tative PCR. In addition, the protein levels of GFAP, signal transducers and activators of transcription 3 ( STAT3 ) and phosphorylated STAT3 ( p-STAT3 ) were examined using Western blot. Results With the ex-tension of intracerebral hemorrhage time, positive sig-nal index and protein expression levels of EGFR gradu-ally elevated, reached the peak on 6 ~10d, and then decreased after 10 d. There was statistical difference ( P<0. 01 ) . The expression levels of GFAP mRNA and protein as well as p-STAT3 were significantly in-creased in cells treated with CNTF alone as compared to control group ( P <0. 01 ) , whereas these effects were almost completely reversed by EGFR siRNA transfection ( P <0. 01 ) . Additionally, there was no statistical difference in STAT3 protein levels among groups ( P >0. 05 ) . Conclusions EGFR expression is upregulated in the cerebral tissues around hemotomas after intracerebral hemorrhage. Gene silence of EGFR contributes to suppressing the activation of astrocytes derived from rats, which may be involved in the block-ade of STAT3 phosphorylation.
3.Human carcinoembryonic antigen-related cellular adhesion molecules 1 mediated susceptibility of Neisseria gonorrhoeae to mouse
Guocai LI ; Qinghui DU ; Xiaohong WANG ; Jinsong WANG ; Feng YU ; Shuangxi LIU ; Rushan XIE ; Hongmei JIAO ; Hua YAN ; Mingchun JI
Chinese Journal of Microbiology and Immunology 2011;31(10):907-911
ObjectiveTo develop a transgenic mouse model for N.gonorrhoeae researches.Methods Human carcinoembryonic antigen-related cellular adhesion molecules 1 (hCEACAM1) eukaryotic expression vector,pCDPGICAM1,was used to generate transgenic mice by microinjection.The funder mice were screened by PCR,sequence analysis,Western blot and fluorescence-activated cell sorting analysis,respectively.The transgenic mice expressing hCEACAM1 were inoculated with N.gonorrhoeae intravaginally.Adhesion and infection of gonococci to mice were analyzed by bacteria culture and microscopy.Results Four (lines 50,53,54,and 59) of the 22 F0 generation transgenic mice were found to carry the transgene.The hCEACAM1 protein was expressed on the cell membrane of various tissues in the line 53 transgenic mouse.Compared with normal mice,N.gonorrhoeae can successfully infect and cause inflammation in the transgenic mice.Conclusion The hCEACAM1 transgenic mouse can be used as an animal model for gonococcal infections.
4.Comparison of efficacy and safety between robotic and laparoscopic pancreatic tumor enucleation
Zhiqiang LI ; Jichun SUN ; Guangping TU ; Shuangxi XIE ; Yunfei LIU ; Dongwen WANG ; Shunmin HE ; Xiao YU
Chinese Journal of General Surgery 2024;33(9):1430-1439
Background and Aims:In the era of minimally invasive surgery,the role of pancreatic tumor enucleation(PTE)in treating benign or low-grade malignant tumors is gaining attention.The Da Vinci robot offers advantages such as enhanced visualization and flexible instrument manipulation,which can ensure the safe implementation of PTE.However,whether robotic pancreatic tumor excision(RPTE)is superior to laparoscopic pancreatic tumor enucleation(LPTE)remains undetermined.Therefore,this study was performed to explore this aspect. Methods:The clinical data of 38 patients who underwent surgical treatment for benign or low-grade malignant tumors in the Third Xiangya Hospital of Central South University from April 2020 to May 2024 were collected.Among them,18 cases underwent RPTE(RPTE group),and 20 cases underwent LPTE(LPTE group).Relevant clinical variables were compared between the two groups,and subgroup comparisons were further conducted for patients with tumors in the head and neck/body/tail of the pancreas. Results:The average operative time for the entire group was 125 min,with an average intraoperative blood loss of 67.89 mL,and no C-grade pancreatic fistula occurred.The incidence rates of B-grade pancreatic fistula,postoperative bleeding,and readmission were 39.5%,21.1%,and 18.4%,respectively,with an average postoperative hospital stay of 11.44 d.Overall,the RPTE group had shorter operative time and less intraoperative blood loss than the LPTE group(both P<0.05).There were no statistically significant differences between the two groups regarding the incidence of B-grade pancreatic fistula,intraoperative bleeding,readmission rate,and postoperative hospital stay(all P>0.05).Subgroup analysis showed that for patients with head tumors,the RPTE group had shorter operative time,less intraoperative blood loss,and a lower incidence of postoperative bleeding than the LPTE group(all P<0.05).However,the differences in the incidence of B-grade pancreatic fistula,readmission rate,and postoperative hospital stay were not statistically significant(all P>0.05).In patients with neck/body/tail tumors,the RPTE group also had shorter operative time and less intraoperative blood loss(both P<0.05),but the differences in incidence of B-grade pancreatic fistula,incidence of postoperative bleeding,readmission rate,and postoperative hospital stay were not statistically significant(all P>0.05). Conclusion:Minimally invasive PTE for the treatment of benign or low-grade malignant pancreatic tumors is safe.Compared to LPTE,RPTE can significantly reduce operative time and intraoperative blood loss and shows certain advantages in reducing postoperative complications,particularly for patients with head tumors.However,the conclusion of this study needs to be confirmed by larger prospective studies.