1.The influence of pretreatment with PPI on helicobacter pylori eradication:a Meta analysis
Jia CHEN ; Chuanfei LI ; Lin LV ; Zhechuan MEI
Chongqing Medicine 2015;(30):4244-4246,4251
Objective To systematically investigate the pretreatment impact of proton pump inhibitor (PPI) on Helicobacter pylori (HP) eradication rate .Methods PubMed ,EMBASE ,Cochrane database ,Web of Science ,Clinical trial .gov ,SinoMed ,China National Knowledge Internet ,WANFANG Data ,VIP database and Google Scholar were used to search for randomized controlled trials(RCT) .HP eradication rate was calculated by per‐protocol analysis (PP) .RevMan 5 .2 was applied to analyze data .Results There were 10 articles included (982 cases) ,43 cases didn′t meet the program have been removed ,a total of 939 cases included .The result showed that there was no significant difference between the pretreatment of PPI group and the control group ,RR= 0 .99 (95% CI:0 .95-1 .04 ,P=0 .75) .Conducted a subgroup analysis according to eradication regimen ,regimen combining a PPI ,amoxi‐cillin and clarithromycin and regimen combining a PPI ,clarithromycin and metronidazole the pooled risk ratio were 1 .02(95% CI:0 .90-1 .14 ,P=0 .79)and 1 .02(95% CI:0 .92-1 .12 ,P=0 .74)respectively ,there were no significant difference as well .Conclusion The pretreatment with PPI does not affect HP eradication rates of triple or quadruple therapies for HP eradication .We can eradi‐cate HP directly for the patients who have used PPI but were diagnosed to be positive to HP .
2.Serum Myocardial Enzymes and High Sensitivity C-reactive Protein Levels in Young Children with Rotavirus A Infection
Aijuan LI ; Chuanfei ZHANG ; Peifen PANG ; Jinhua ZHANG
Chinese Journal of Nosocomiology 1994;0(01):-
OBJECTIVE To detect the changes in young children,with diarrhea including rotavirus A antigens in stool specimens,serum myocardial enzymes,high-sensitivity C-reactive protein(hs-CRP) and alteration of intestinal flora.METHODS Rotavirus A antigens in stool specimens were detected by immunologic colloidal gold,serum myocardial enzymes were measured by full automatic analyzer,hs-CRP level of serum specimens was measured by gold labeled test,and alteration of intestinal flora was also analyzed.The same method was also applied in control group.RESULTS Among 234 diarrhear cases of young children,124 cases with positive rotavirus A antigens appeared the high level of serum myocardial enzyme and hs-CRP compared with the control group.Candida albicans from stool specimens was detected in 45 cases with positive rotavirus A.CONCLUSIONS The results indicate that rotavirus A can cause gastrointestinal tract infection in young children,lead in alteration of intestinal flora,damage myocardium and lead to high level of hs-CRP.All these laboratory results are significant for clinical diagnosis and treatment.
3.N terminal sequencing for practical detection of monoclonal antibody.
Wei GUO ; Chuanfei YU ; Meng LI ; Lan WANG ; Feng ZHANG ; Chunyu LIU ; Wenbo WANG ; Kai GAO
Chinese Journal of Biotechnology 2014;30(9):1473-1480
Here we discuss whether N terminal sequencing is appropriate as one of the conventional control methods for monoclonal antibody products. We determined the N terminal sequences of two monoclonal antibody products targeting two antigens separately with both Edman degradation and mass peptide spectrometry. We also identified the characteristic peptide fragments with mass spectrometry. Furthermore, we analyzed their heterogeneity with ion exchange chromatography, capillary zone electrophoresis and Imaged Capillary Isoelectric Focusing. Edman degradation method showed that the N terminal 15 amino acids of heavy and light chains of the two monoclonal antibodies were identical. Peptide mass spectrometry demonstrated that T1 peptide fragments of heavy and light chains of the two antibodies were also the same. But in contrast, peptide mapping and the three analytical methods for heterogeneity analysis could effectively identify and differentiate the two antibodies. The N terminal sequences of two monoclonal antibodies are identical because the number of framework sequences of humanized or human monoclonal antibodies is relatively limited, so whether N terminal sequencing analysis could be regulated as one of the practical control methods should be carefully discussed. Our work also proves that the above analytical methods could combinatorially applied to the identification of monoclonal antibody products, and are more objective compared to N terminal sequencing.
Amino Acid Sequence
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Antibodies, Monoclonal
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isolation & purification
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Chromatography, Ion Exchange
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Humans
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Isoelectric Focusing
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Mass Spectrometry
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Peptide Mapping
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Peptides
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Sequence Analysis, Protein
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methods
4.Comparative study of size and charge heterogeneities of anti-TNF-αantibodies by high performance liquid chromatography
Wei GUO ; Wenbo WANG ; Chuanfei YU ; Feng ZHANG ; Lan WANG ; Chunyu LIU ; Meng LI ; Kai GAO
Chinese Journal of Microbiology and Immunology 2014;(9):723-726
Objective To analyze the differences of size and charge heterogeneities between origi-nal humanized anti-TNF-αantibody and four similar biotherapeutic products ( SBP ) .Methods The size exclusion chromatography ( SEC-HPLC ) and weak cation exchange chromatography ( WCX-HPLC ) were used to analyze the size and charge heterogeneities , respectively.Carboxypeptidase B (CpB) treatment was employed to analyze the source of charge heterogeneity of the antibody products .Results Four SBPs showed the same pattern with the originator in SEC-HPLC, and no significant difference with the percentage of mono-mer was observed .The percentages of the aggregates of SBP-3 and SBP-4 were a little higher than those of the originator .The charge distribution of SBPs was significantly different from the originator ′s, especially in the basic region .The results from the samples treated with CpB indicated that the difference of charge distri -bution in the basic region might be caused by the C-terminal lysine variants .Conclusion Four SBPs showed similar size heterogeneity with the originator , but significant differences with charge heterogeneity were observed among them .The study suggested that more attention should be paid to the charge heterogene -ity analysis of the biosimilar products .
5.Size heterogeneity analysis of monoclonal antibody products
Chuanfei YU ; Wenbo WANG ; Meng LI ; Lan WANG ; Feng ZHANG ; Chunyu LIU ; Kai GAO
Chinese Journal of Microbiology and Immunology 2014;(9):718-722
Objective To compare the capability of capillary electrophoresis-sodium dodecyl sul-fate ( CE-SDS) and size exclusion-high performance liquid chromatography ( SE-HPLC) for analysis of size heterogeneity of monoclonal antibody products .Methods The size heterogeneity of one humanized anti-VEGF monoclonal antibody was analyzed by using non-reduced and reduced CE-SDS, and conventional , de-natured and denatured reduced SE-HPLC.Results The percentage of aggregates detected by non-reduced CE-SDS (0.82%±0.01%) was equal to that by using denatured SE-HPLC (1.05%±0.02%), but it was significantly lower than that by using conventional SE-HPLC analysis (5.08%±0.10%).With regard to fragments analyzed with non-reduced antibodies, its percentage was (7.12±0.04)% measured by non-re-duced CE-SDS analysis that was significantly higher than that by conventional SE -HPLC analysis (0.02%± 0.01%) and denatured SE-HPLC analysis (0.62%±0.01%).Using reduced antibodies , the percentage of fragments was (3.19±0.50)%tested by reduced CE-SDS analysis that was significantly higher than that by using denatured reduced SE-HPLC analysis (0.07%±0.01%).Conclusion Conventional SE-HPLC was more objective than CE-SDS for content analysis of aggregates , as both the covalent and non-covalent forms of aggregates could be detected .Non-reduced CE-SDS could demonstrate the content of clips , while reduced CE-SDS showed the degraded fragments .Therefore, CE-SDS had an advantage over conventional SE-HPLC for content analysis of fragments .The use of the two analytical methods in combination provided solid techni-cal supports for the quality control of size heterogeneity of monoclonal antibodies .
6.Development of a novel reporter gene method for determination of ADCC potency of anti-CD20 monoclonal antibody.
Chunyu LIU ; Lan WANG ; Wei GUO ; Chuanfei YU ; Feng ZHANG ; Wenbo WANG ; Meng LI ; Kai GAO
Acta Pharmaceutica Sinica 2015;50(1):94-8
The biological activity of ADCC by anti-CD20 monoclonal antibody was determined by BioGlo™ Luciferase Assay System using Jurkat/NFAT-luc+FcγRIIIa cell line as effector cell and WIL2-S cell line as target cell. The developed method was verified for specificity, precision and accuracy. Anti-CD20 monoclonal antibody showed a dose-response mode by the developed method, and the determination result complied with the following four-parameter equation: y = (A-D)/[1 + (X/C)(B)] + D. The optimized parameters of the method were determined including the antibodies diluted concentration (18,000 ng·mL(-1)), dilution rate (1:5), the ratio of effector cell and target cell (6:1), and induction time (6 h). The values of eight independent tests have passed a statistical test for curve regression analysis, linear or parallelism, which showed the method possessed good specificity. Four different dilute groups of recovery rates sample were determined for 3 times, and the result showed mean relative potencies of (44.39±3.93)%, (72.74±2.78)%, (128.28±7.01)% and (168.19±2.70)% respectively, with a variation coefficient of less than 10%, and the recoveries of (88.78±7.85)%, (96.99±3.70)%, (102.63±5.61)% and (112.12±1.80)% respectively. A novel reporter gene method for determination of biological activity of ADCC by anti-CD20 monoclonal antibody was successfully developed, which showed strong specificity, good reproducibility and high accuracy, and might be used routinely.
7.The study on CASP 8-652 6N I/D polymorphism and susceptibility of 2 type diabetes mellitus
Xuemei HE ; Juan LI ; Xiaoping TANG ; Yongping HE ; Chuanfei HU ; Feng CHEN ; Qin WAN ; Zhuang CHEN
The Journal of Practical Medicine 2014;(19):3073-3075
Objective To investigate the association of cysteine aspartic acid specific protease 8 (CASP 8) gene-652 6N Insertion/Deletion polymorphisms and susceptibility of type 2 diabetes mellitus (T2DM). Methods CASP 8 gene -652 6N I/D polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing in 414 controls and 410 patients with T2DM. Results I/I, I/D and D/D genotype frequency were 56.5%, 38.9%, 4.6%in controls and 58.0%, 32.9%, 9.0%in T2DM group respectively (P<0.05). The risk in D/D genotype people was 1.916 times than I/I genotype (adjusted OR=1.916, 95%CI=1.199~3.054, P<0.05). The fasting blood sugar of D/D genotype people was significantly higher than that of I/D and I/I genotype people (P<0.05). Conclusions CASP 8 gene-652 6N I/D polymorphisms are associated with T2DM outbreak.
8.Determination of drug antibody ratio in an antibody-drug conjugate.
Chuanfei YU ; Meng LI ; Wei GUO ; Lan WANG ; Feng ZHANG ; Chunyu LIU ; Wenbo WANG ; Junzhi WANG ; Kai GAO
Acta Pharmaceutica Sinica 2014;49(3):363-7
This paper reports the determination of the drug antibody ratio in an antibody-drug conjugate with two methods, i.e. LC-MS and UV/VIS, and to provide a reliable method to scientifically evaluate and effectively control the drug antibody ratio. Deglycosylated sample was analyzed with C4 column followed by MS, and the number of conjugated drugs in the antibody was determined by the molecular weight increase due to the addition of different number of drugs to the antibody, and then drug antibody ratio was calculated by weighted average of different number of drugs conjugated to the antibody. Optical density at 252 and 280 nm was measured with UV/VIS, and due to the difference of extinction coefficients between the antibody and the drug, the drug antibody ratio was calculated from linear equation with two unknowns. The drug antibody ratio was 3.21 and 3.25 respectively measured by the two methods, and the results were similar with the two methods. Our study indicated that both methods, LC-MS and UV/VIS, could be applied to the analysis of drug antibody ratio of the antibody drug conjugate.
9.Effect of aquaporin 9 on proliferation, apoptosis, invasiveness and migration of HepG2 cells.
Chuanfei LI ; Xiaofeng CHEN ; Wenguang ZHANG ; Jia LIU ; Lin LYU ; Zhechuan MEI
Chinese Journal of Hepatology 2015;23(6):437-442
OBJECTIVETo investigate the impact of aquaporin 9 (AQP9) on the proliferation,apoptosis,invasiveness and migration of hepatocellular carcinoma cells using the HepG2 cell line.
METHODSA lentiviral vector targeting the coding region of human AQP9 was constructed. The recombinant lentiviral vector was harvested from the 293T cell line and transfected into the HepG2 cell line; resistant cell clones were selected with puromycin. Three groups of cells were established, including the CC group (control without lentiviral vector), the PWPI group (control with empty carrier virus), and the AQP9 overexpression group (experimental with the AQP9 recombinant virus). Transfection efficiency was validated by laser confocal microscopy.Expression of AQP9 was detected in the transfected HepG2 cells by westem blotting (protein) and real-time qPCR (mRNA). AQP9 effects on proliferation, migration, invasion and apoptosis of the HepG2 cell line were assessed by plate colony formation assay, woumd healing assay, transwell assay and flow cytometry.
RESULTSThe green fluorescent protein of the recombinant lentiviral vector was appropriately distributed in the cell membrane. The AQP9 overexpression group showed significantly higher AQP9 mRNA and protein levels than the PWPI group and the CC group (both P < 0.01). Cells with AQP9 overexpression showed a lower colony formation rate (16.93±3.19% vs. CC group: 23.53±2.10% and PWPI group: 23.00±2.02%; F=6.46, P=0.032) and a lower overall apoptosis rate (44.96±3.53% vs. CC group:19.7±2.49% and PWPI group: 24.37±2.38%; F=66.88, P < 0.01). The AQP9 overexpression group also showed significantly higher number of cells in the G1 stage and significantly lower number of cells in the S stage (G1: 66.58±0.99% and S:15.25±1.81%), significantly smaller cell migration distance (P=0.01 < 0.05), and significantly suppressed invasiveness (17±8 vs. CC group:109+/-9 and PWPI group: 95±11; P=0.01 < 0.05).
CONCLUSIONIn HepG2 cells, AQP9 significantly reduces the migrative and invasive capabilities, induces cell apoptosis, and inhibits cell proliferation via cell cycle arrest at the G1/S phases.
Apoptosis ; Aquaporins ; Cell Movement ; Cell Proliferation ; Genetic Vectors ; Hep G2 Cells ; Humans ; Lentivirus ; Neoplasm Invasiveness ; RNA, Messenger ; Transfection
10.Application of online teaching in the teaching of medical imaging diagnostics
Chinese Journal of Medical Education Research 2022;21(7):847-849
Objective:To explore the application and effectiveness of online teaching in the teaching of medical imaging diagnostics.Methods:A total of 134 undergraduate students of Medical Imaging Technology Department of Chongqing Medical University in Batch 2016 and Batch 2017 were selected as the research objects. They were divided into control group and experimental group with 67 students in each group. The experimental group adopted the online teaching mode based on Xuexitong and Tencent Meeting learning platforms; while the control group adopted the traditional teaching mode. The final grades of two groups were compared, and self-made questionnaires were anonymously investigated, so as to realize the evaluation of online teaching effects. SPSS 21.0 was used for rank sum test.Results:The qualification rate of final results in the experimental group and control group were respectively 80.6% (54/67) and 64.2% (43/67). The qualification rate of final results in the experimental group students was significantly better than that of the control group ( P<0.05). A total of 134 survey questionnaires were distributed and all recovered. The survey questionnaires showed that experimental group was superior to the control group in self-learning ability, analyzing and solving problems ability, communication skills, interest and enthusiasm in learning ( P<0.05). Conclusion:The online teaching is conducive to improving the qualification rate of final results, self-learning ability, analyzing and solving problems ability, communication skills, interest and enthusiasm in learning for the teaching of medical imaging diagnostics, which has good teaching effects and qualities and is of great promotion significance.