1.False positives resulted from colony PCR in rapid identification of recombinant clones from phage antibody library
Sihe ZHANG ; Guoqiang BAO ; Jinliang XING
Medical Journal of Chinese People's Liberation Army 1982;0(03):-
Objective To evaluate the reliability of colony PCR in identifying the recombinant clones selected from phage antibody libraries. Methods The digested pComb3 vector and Lc fragments, Lc library plasmid, and Fd fragments were ligated successively. The ligation product was transformed into Escherichia Coli strain XL 1-blue bacilli by electroporation and thus murine Fab phage antibody library was constructed.The transformed recombinant clones selected randomly from libraries were identified simultaneously by colony PCR, plasmid PCR and restriction enzyme digestion. The identification consistency was analyzed. The interference was excluded by control PCR using the relevant constituents as template. Results The educed library content of Lc library was 1.175?10 6 CFU and the content of Fab antibody library was 1.02?10 6 CFU. Different recombinant percentages were obtained through three different identification methods (the Lc positive recombinant percentages by colony PCR, plasmid PCR and enzyme digestion were 100%, 78% and 78%, respectively; the Fd positive recombinant percentages by three methods were 90%, 66% and 66%, respectively; the dual positive recombinant (Fd and Lc insert simultaneously) percentages by three methods were 90%, 50% and 50%, respectively). A high frequency of false-positives appeared in colony PCR identification. Nonspecific amplification of control PCR was presumably induced by some intracellular components in XL 1-blue bacilli. Conclusion The identification of the recombinant clones selected from phage antibody libraries by colony PCR remains ambiguous. So it is our assertion that the traditional identification methods such as plasmid PCR or enzyme digestion are more accurate and will less false positive results.
2.Construction of human-mouse hybrid Fab phage antibody libraries
Guoqiang BAO ; Qingjiu MA ; Jinliang XING
Medical Journal of Chinese People's Liberation Army 1983;0(05):-
Objective To construct human-mouse hybrid Fab phage antibody libraries and to select target Fab genes. Methods With Fd repertoire genes of PBMC from hepatoma patients and the chemeric light chain gene of cFab-HAb18, two hybrid Fab phage antibody libraries(pComb3 and pComb3X) were constructed. The GST fusion and non-fusion HAb18GE were used as antigens to select the target antibodies with the optimized strategies of amplifying and screening. Results When pComb3 displaying library was cultivated at 37℃, the target fragments could not be cut out with the restriction endonucleases from most clones of the library, which was an indication of “recombinant-deletion”. But no “recombinant-deletion” was found in pComb3X displaying library. Because of the serious cross-reaction, the phage-display Fab ELISA could not be used for the selection of positive clones. But positive clones could be identified in the supernatant of lysate with ELISA afterbeing induced by IPTG. Conclusion Through the construction of HuMFab phage antibody libraries and the optimization of screening strategies, we get the desired HuMFab genes for subsequent research.
3.STUDY OF CHEMOTHERAPY SENSITIVITY IN TUMOR CELL LINES ASSESSED BY APOPTOSIS
Tonghai XING ; Zhihai PENG ; Guoqiang QIU
Tumor 2001;(1):20-22
Objective To study chemotherapy sensitivity and apoptosis in tumor cell line.Methods Two different human colon carcinoma cell lines, LoVo and Ls-174-t were incubated with DDP,MMC,5-FU,EPI at various peak plasma concentrations (PPC), 1/10PPC,1/5PPC,5PPC and 10 PPC. Apoptosis was detected by FACScan and TUNEL technique after 24 hours and 48 hous. Cell growth inhibition rates were assessed by MTT, DNA ladder were examined by agarose electrophoresis.Results At 48 hours, the highest cellular apoptosis rates were observed with PPC which was assessed by FACScan technique. There was a positive linear correlation between apoptosis assessed by TUNEL technique and growth inhibition rates of cells determined by MMT(P<0.05).Conclusion Using Annexin-V-Fluos staining FACScan technique to assess apoptosis of tumor cells is an exploring and useful method which can be used to choose both kinds and doses of chemotherapeutic drugs.
4.THE EFFECT OF MIFEPRISTONE ON APOPTOSIS AND APOPTOTIC GENE Fas/FasL EXPRESSION OF DECIDUA IN HUMAN EARLY GESTATIONAL PERIOD
Feng DING ; Guoqiang FU ; Fuq XING
Medical Journal of Chinese People's Liberation Army 1981;0(04):-
The present study was designed to investigate the effects of mifepristone on apoptosis of the decidual tissue cells and apoptotic correlated gene Fas/FasL expression in human early gestational period. The extent of DNA fragmentation of apoptotic cells were assessed by using an in situ terminal transferase reaction to label free 3′ ends of the DNA.The expression of Fas, FasL in the deciduas was examined by in situ hybridization with cDNA probe and immunohistochemical staining with polyclonal antibodies, respectively. The results showed that there were evident apoptosis in decidual tissues at about 40 days of gestation. Fas and FasL were strongly expressed in these decidual tissues. At about 50 days of gestation, there were a few apoptotic cells in the decidual tissues. Expression of Fas, FasL decreased at the same time. More apoptotic cells were observed in decidual tissues after adiministration of Mifepristone (RU486) in about 50 days of gestation. Fas, FasL mRNA and protein were up regulated after administration of Mifepristone. The results suggested that the induction of apoptosis by Mifepristone in decidual tissues might be one of the major mechanisms with regards to contraceptive and antigestational effects of mifepristone. Fas pathway might participate in the process of decidua apoptosis induced by RU486.
5.Effects of HGF in Celsior solution on levels of INF-γ. IL-4 and IL-10 in a rat liver transplantation model
Tao LI ; Huamei TANG ; Xing SUN ; Guoqiang QIU ; Zhihai PENG
Chinese Journal of Hepatobiliary Surgery 2010;16(7):524-526
Objective To explore the impact of recombinant human hepatocyte growth factor (rhHGF) in Celsior (CS) solution on the expression of INF-γ, IL-4 and IL-10 in a rat liver transplan-tation model. Methods After flushed with CS solution with addition of rhHGF (experimental group) or saline (control group), NHBD livers were stored at 4℃; for 16 h.then they were transplanted using the two-cuff technique with arterial reconstruction. The serum levels of INF-γ, IL-4 and IL-10 at lh after reperfusion were detected using ELISA. The INF-γ, IL-4 and IL-10 mRNA in the corresponding liver tissue were determined by RT-PCR. The 7-day survival rate was calculated and the histopatho-logical examination results were analyzed by hematoxylin and eosin staining. Results Compared with the control group, the experimental group showed lower INF-γ level and higher IL-4 and IL-10 levels in serum at 1 h after reperfusion (P<0. 05). The level of INF-γ mRNA in liver tissue was significant decreased at 1 h after reperfusion (P<0. 05) , and the level of IL-4 and IL-10 mRNA was significantly increased in the experimental group (P<0. 05). In experimental group, recipients got a better survival rate and histopathological examination showed a well-preserved hepatic architecture without hepatocyte necrosis, milder sinusoidal and portal congestion. Conclusion Adding exogenous rhHGF in CS solu-tion can protect NHBD livers from ischemia-reperfusion injury and prolong the survival in rats, which might be due to down-regulation of TNF-γ and up-regulation of IL-4 and IL-10.
6.The Screening of Human Anti-Hepatoma Fd Fragments Guided with the Chemeric Light Chain of HAb18
Guoqiang BAO ; Qingjiu MA ; Jinliang XING ; Xiangmin YANG ; Zhinan CHEN
Chinese Journal of Cancer Biotherapy 1995;0(03):-
Objective: To select anti-HAb18G (hepatoma associated antigen) human Fd fragments with guided selection of L chain of chimeric Fab-HAb18. Methods: The human Fd repertories genes were amplified by RT-PCR from PBMC of hepatoma patients, and cloned into the vector pComb3X with chimeric L chain to construct the human-mouse hybrid Fab phage library. HAblSGE, extracellular region of HAblSG, was used as antigen to screen. The positive clones was obtained by ELISA and FCM with p Ⅲ-fusion Fab antibody. The DNA sequences were analyzed. Results: A human-mouse Fab antibody library were constructed with 2?107 PFU. After 6 rounds panning, 7 positive clones were obtained with ELISA and FCM. And sequences of 2 clones with better affinity were same. The CHI belonged to the IgG2 class as the parent Fd, and the variable region belonged to VH3 family. Conclusions: Through the construction of the HuMFab phage antibody library and chemeric L chain-guided selection, we get the available human Fd fragments for subsequent research.
7.Relationship between Fas/FasL expression and apoptosis of colon adenocarcinoma cell lines
Zhihai PENG ; Tonghai XING ; Guoqiang QIU ; Al ET
China Oncology 1998;0(01):-
Purpose:To study the relationship between Fas/FasL expression and apoptosis of colon adenocarcinoma cell lines induced by chemotherapeutic drugs and to screen out hypersensitive drugs. Methods:Colon adenocarcinoma cell lines LS174T and LoVo were incubated respectively in cultural media with DDP,MMC,5 FU and EPI at concentrations of PPC(plasma peak concentration),1/10 PPC,1/5 PPC,5 PPC and 10 PPC. Fas/FasL expression and apoptosis were assessed by FACScan, and DNA ladder was examined by agarose gel electrophoresis. Results:In LS174T cells, Fas expression and apoptosis of DDP group, MMC group and EPI group reached their highest peaks at 1/5 PPC or PPC,and Fas expression and apoptosis were positively correlated by relativity analysis. There was no significant correlation between Fas expression and apoptosis in LoVo cells. Conclusions:We could find out hypersensitive drugs and their appropriate dosage according to apoptosis, partly according to Fas expression. The different apoptosis paths between LS174T cells and LoVo cells demonstrate the importance of individualized selection of chemotherapeutic drugs.
8.The efficacy of trans-cranial magnetic stimulation for relieving post-stroke depression:A meta-analysis
Yu JIN ; Guoqiang XING ; Zhiwei GUO ; Qing TANG ; Qiwen MU
Chinese Journal of Physical Medicine and Rehabilitation 2016;38(5):384-393
Objective To assess the effectiveness of repeated trans-cranial magnetic stimulation ( rTMS) in relieving post-stroke depression ( PSD). Methods PubMed, Embase, the Cochrane library, Web of Science, CNKI, WANFANG, and VIP were searched for reports of randomized, controlled trials of rTMS treatment of PSD published before June 2015. Crude standardized mean differences ( SMDs) and odds ratios with 95% confidence in-tervals ( CIs) were calculated for depression intensity and effectiveness rate after treatment using random or fixed effects models. Results Twenty-four studies involving 856 rTMS-treated patients and 802 control patients were in-cluded in the meta-analysis. The results showed that compared with the control group, PSD patients showed significant reductions in depression after rTMS treatment ( SMD=-1.36;95% CI-1.6 to-1.12;P≤0.05) . The total effective-ness rate in the treated group was 85% with a reduction in NIHSS score ( SMD=-0.82;95% CI-1.2 to-0.44;P≤0.05) . Subgroup analysis showed that neither the frequency of rTMS stimulation, the site stimulated, nor time after stroke had a significant influence on the effectiveness of rTMS. Additionally, a few studies reported adverse reactions after rTMS. Conclusion rTMS appears to be a safe and effective therapy for PSD. Further well-controlled trials may elucidate the mechanism underlying the placebo effects of the sham rTMS observed among PSD patients.
9.The clinical diagnosis and treatment of malignant gastrointestinal stromal tumor
Yan HONG ; Bo LU ; Xianqiu XIAO ; Xing GAO ; Guoqiang ZHANG ; Fengying ZHOU ; Xiao DONG ; Weida GONG
Chinese Journal of Primary Medicine and Pharmacy 2011;18(14):1904-1906
Objective To study the clinical diagnosis and treatment of malignant gastrointestinal stromal tumor. Methods To retrospectively analyze the clinical data of 28 cases with malignant gastrointestinal stromal tumors underweat surgical treatment . Results The malignant gastrointestinal stromal tumor in adults were more than 50 years old,71.4%(20/28) ,and common clinical symptoms were gastrointestinal bleeding,anemia,and pain. The lesion site: 19 cases of gastric bowel, 8 cases of small intestine, 1 case of colon, radical excision in 22 cases, local excision palliative resection in 5 cases, three cases were multi-visceral resection. Conclusion Malignant gastrointestinal stromal tumor could be diagnosed by the means of endoscopic imaging and clear,and preoperative diagnosis was difficult. Surgical resection was the pathology diagnosis and treatment of primary method,if necessary,to ensure multi-visceral resection of the tumor to prevent recurrence of thoroughness, had important significance.
10.The efficacy and safety of autologous cryopreserved platelet transfusion in management of thrombocytopenia after chemotherapy in hematological malignancy
Guoqiang LIU ; Huifang DING ; Xifing LU ; Min XU ; Jian XING ; Xia ZHAO ; Fang HAN ; Yinghui SHANG
Chinese Journal of Internal Medicine 2012;51(3):188-191
Objective To investigate the efficacy and safety of autologous cryopreserved platelet transfusion in the management of thrombocytopenia after chemotherapy in hematological malignancy.Methods A total of 40 patients diagnosed as hematological malignancy with complete remission were equally assigned into study group and control group.During chemotherapy interval in the study group,when platelet counts exceeded 120 × 109/L,autologous platelets were collected with CS3000 Cell Separator and cryopreserved at-80℃ with 5% dimethylsulfoxide.When platelet counts dropped below 15 × 109/L after chemotherapy,autologous platelets were thawed with 40℃ water bath and transfused back to each patient.In the control group,when platelet counts dropped below 15 × 109/L after chemotherapy,allogeneic fresh platelets were transfused.Median loss during the freeze-thaw-wash procedure in study group was observed,and the 1 h,24 h corrected count increments(CCI)were calculated in the both groups.The hemostatic effects and adverse reactions were also observed.Results In the control group,1hCCI and 24hCCI were (19.3 ±6.1)× 109/L and(12.2 ± 7.0)× 109/L,respectively,with the effective rate of 80% and the transfusion reaction rate of 45%.Totally 20 collection and transfusions were finished in the study group.A total of(3.4-8.5)× 1011 platelet were obtained in each collection.Platelet recovery after freezing and thawing was(73.51 ±9.03)%(62%-83%).1hCCI was(17.4±7.6)× 109/L,24h CCI was(10.5 ±5.8)× 109/L and the effective rate was 85%.There was no significant different between the two groups (P > 0.05).The transfusion reaction rate was 15 %,which was significantly lower than that of the control group(P < 0.05).Meanwhile,adverse reactions were occurred less in the study group.Conclusion This study demonstrates that autologous cryopreserved platelet transfusions can be safely administered for supporting thrombocytopenia in hematological malignancy patients undergoing chemotherapy.