1.The role of neuronal autophagy in hypoxic-ischemic brain injiny
Qianyi HE ; Guoping PENG ; Benyan LUO
International Journal of Cerebrovascular Diseases 2009;17(12):940-943
Autophagy is a metabolic pathway that widely presents in eukaryotic cells through the lysosomal mechanism to degrade its components. Autophagy regulates cell death not only by activating classic autophagosomal-lysosomal pathway, but also by influencing the occurrence and development of apoptosis and necrosis. Currently, the effect of autophagy in neuronal injury after acute cerebral ischemia/hypoxia and its specific mechanisms remain unclear. Studies have demonstrated that the autophagy after ischemia/hypoxia has a neuroprotective effect, such as maintaining neuronal homeostasis and reducing neuronal death; but other studies have also suggested that autophagy may aggravate neuronal injury after ischemia/hypoxia by activating multiple pathways, and even induce neuronal death.
3.Transformation of alisol B 23-acetate in processing of Alisma orientalis
Yunfeng ZHENG ; Yulan ZHU ; Guoping PENG
Chinese Traditional and Herbal Drugs 1994;0(10):-
Objective To study the transformation mechanism of triterpenes in processing of Alisma orientalis. Methods The triterpene transformations of A. orientalis pre and post-processing were comparatively analyzed by techniques of HPLC and Packed Column Supercritical Fluid Chromatography (SFC). Results In baked processing (70 ℃) of A. orientalis, little alisol B 23-acetate was transformed into alisol A 24-acetate and alisol B.However, more alisol B 23-acetate was transformed into alisol A 24-acetate and alisol B, then both of them were further transformed into alisol A in processing under high temperature (160-200 ℃). Conclusion Transformation of alisol B 23-acetate has two routes when A. orientalis is processed under high temperature: For one, alisol B 23-acetate is rearranged into alisol A 24-acetate which could be deacetylated into alisol A; for the other; it is deacetylated into alisol B first, then transformed into alisol A.
4.The construction, expression and immunological activity study of eukaryotic vector expressing cytotoxic T lymphocyte-associated antigen-4 ScFv and hepatitis B virus-S gene
Guoping PENG ; Dangjiu ZHAO ; Cheng ZHOU ; Linfu ZHOU ; Zhi CHEN
Chinese Journal of Infectious Diseases 2012;30(6):324-329
Objective To construct the eukaryotic vector that expressing hepatitis B virus (HBV) S and the single fragment of variety chain (ScFv) of monoclonal antiboy against cytotoxic Tlymphocyte-associated antigen-4 (CTLA-4) and to analyze the immunological activity of recombinant S-ScFv protein.Methods The oringially constructed pSect2/ScFv4F10 and pSect2/S were double enzyme digested by Sfi I and Hind Ⅲ,respectively.Then the HBV S gene was cloned into the pSect2/ScFv4F10 vector.The pSect2/ScFv4F10 and pSect2/S-ScFv4F10 were expressed in Chinese hamster ovary (CHO) cells,and the expressed proteins were verified through sodium dodecyl sulfatepolyacrylamide gelelectrophoresis(SDS-PAGE)andWesternblotting.Afterultrafiltration concentration and affinity chromatography,the biological affinity of the expressed ScFv4F10 and S-ScFv4F10 proteins were examined by competitive enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR) technology.The comparison between groups was done by One-way ANOVA.ResultsThe eukaryotic expression vector of pSect2/S-ScFv4F10was successfully constructed,and relative molecular mass of the expressed protein of S-ScFv4 F10 was about 52 000 that analyzed by SDS-PAGE and Western blotting.With the fixed concentration of 4F10-mAb against CTLA-4,the A570 value of the mixed reaction with purified CTLA-4 antigen gradually increased with the decrease of ScFc fusion protein proportion; when the molar ratio of ScFv,S-ScFv4F10∶4F10=2∶1,the competitiveinhibitionratesagainst 4F10conjugatedantigenwere72.6%and64.5%,respectively.The affinity constants of association kinetics for CTLA-4 mAb,ScFv4F10 and S-ScFv4F10 with CTLA-4 antigen were 7.29 × 108 mol/L,9.52 × 106 mol/L and 2.04 × 106 mol/L,respectively,and the dissociation constants of KD were 1.40 × 10-9 mol/L,1.05 × 10-7 mol/L and 4.91 × 10-7 mol/L,respectively.ConclusionsThe eukaryotic expression vector of pSect2/S-ScFv4F10is successfully constructed,and the recombinant protein of S-ScFv4 F10 has a fairly high affinity with CTLA-4 antigen.
5.Large mitochondrial DNA deletions in ultraviolet B-induced cutaneous photodamage
Yina WANG ; Hong FANG ; Guoping PENG ; Haifeng LU
Chinese Journal of Dermatology 2009;42(1):45-48
Objective To analyze the association between mtDNA mutations and photodamagc after ultraviolet B (UVB) irradiation. Methods Primary human skin fibroblasts (HSF) and primary human epi- dermal keratinocytes of adult (HEKa) were irradiated by sub-lethal doses of UVB thrice a day for 4-5 days. Thereafter, genomic DNA was extracted from irradiated cells and conventional PCR was applied to detect the frequency rates of 4977 bp and 3895 bp mtDNA deletion. To quantitatively analyze the mutation levels, SYBR Green real-time PCR method was performed. Results In both cell lines, the frequency rates and relative copy number of deletions increased with the cumulative doses of UVB exposure (P<0.05). The prevalence rate of 3895 bp deletion peaked 53.3% and and relative copy number reached (49.63±4.38)×10-5, showing a more intense response to the accumulation of UVB radiation than 4977 bp deletion. In HSF, the minimum cumu- lative dose of UVB radiation was 150 mJ/cm2 for the induction of 3895 bp deletion, and 200 mJ/cm2 for the induction of 4977 bp deletion. It seemed that mtDNA deletion was more readily to be induced by UVB radia- tion in HSF than in HEKa. Conclusions The development and accumulation of mtDNA mutation are intimately related with cumulated UVB dose received by skin cells, and the 3895 bp deletion is more reliable in moni- toring the photodamage caused by UV than 4977 bp deletion. Therefore, the 3895 bp deletion may serve as a biomarker for the detection of photodamagc in skin cells. HSF appear to have an increased susceptibility to UVB radiation, which results in a higher frequency and level of mtDNA mutations compared with HEKa.
6.Oxidative stress in human skin fibroblasts induced by UVB irradiation
Yina WANG ; Wei WU ; Guoping PENG ; Hong FANG
Chinese Journal of Dermatology 2008;41(7):465-468
Objective To observe the aging,apoptosis,cell cycle arrest and oxidative stress in human skin fibroblast(HSF)induced by UVB,and to detect the expression profiles of p66Shc,a determinant of oxidative stress response and life span,in this process.Methods HSF cells were exposed to UVB at a subcytotoxic dosage twice a day for three days.The cells without exposure served as control.After another 24-hour culture,SA-β-Gal staining was performed to evaluate the senescence state of the cells,flow cytometry to observe cell apoptosis;cell cycle arrest was detected by serum starvation and flow cytometry:ELISA was applied to detect intracellular levels of superoxide dismutase(SOD)and malondialdehvde(MDA),and Western blotting to analyze the expression of p66Shc protein.Results The percentage of cells positive for SA-β-Gal staining increased from 0 to 98.3% after UVB radiation,which strongly suggested an aging state of HSF cells.The percentage of apoptotic cells increased from 0.96% to 37%.and 80.07% of the HSF cells were arrested in G0/G1 phase following the irradiation.Intracellular SOD activity decreased from(52.35±4.97)ng/g to(7.81±0.68)ng/g(P<0.01).while intracellular MDA was found to increase from(3.52±0.34)ng/g to(33.91±3.20)ng/g(P<0.05).The p66Shc protein was found to be weakly expressed in HSF in 24 hours following the exposure to UVB,and a stronger expression was noted 48 hours later.Conclusions HSF cells are induced into a state of senescence associated with oxidative stress after UVB irradiation,which may be applied as an in vitro model in aging research.The expression of p66Shc is increased in HSF during this process,and further studies are needed to explore the relation between p66Shc and oxidative stress as well as cellular aging.
7.Study on the realationship between the high density lipoprotein and atherosclerosis
Peng ZHANG ; Guoping YIN ; Yun HU ; Jianhua MA ; Xiaoming MAO
Chinese Journal of Primary Medicine and Pharmacy 2011;18(23):3175-3176
Objective To investigate the presence of type 2 diabetes dyslipidemia,and the association with HDL levels and vascular complications in diabetes.Methods Of 524 cases of type 2 diabetes,fasting blood lipids,blood glucose,glycated hemoglobin results,blood basic data,the level of lipid controlling and based data of the patients were observed.The relevance between abnormal blood lipids and vascular atherosclerosis was analyzed.Results Type 2 diabetic patients have lipid metabolism,in 524 type 2 diabetes patients,58.4% had lipid disorder;The serum level of HDL in atherosclerosis group[(0.8 ±0.26)mmol/L]was significantly lower than that in non-atherosclerotic group[(0.95 ± 0.43)mmol/L](t =1.648,P < 0.05).Conclusion The decreasing of HDL had relationship to vascular atherosclerosis in patients with type 2 diabetes.
8.Study on extraction technology of Zhixuan Granula
Hongmei WEN ; Wei LI ; Guoping PENG ; Quan ZHU ; Zhengxin ZHANG
Chinese Traditional and Herbal Drugs 1994;0(06):-
Object To optimize the preparation procedure for Zhixuan Granula (ZXG). Methods The optimum extracting conditions of ZXG were selected by orthogonal test with the active components: 23-acetate alisol B, atractylenolide I, and dried extract as the index, it mice sedation of ZXG was clarified by pharmacodynamics. Results The optimum preparation procedure was as follows: Rhizoma Alismatis and Rhizoma Atractylodis Macrocephalae were extracted with alcohol first, adding 12-fold 70% alcohol by refluxing, extracting twice, 2 h once, then extracted with water, adding 14-fold water, extracting twice, 2 h once. The extract showed the obvious effect on sedation of mice. Conclusion The optimum preparation procedure is reliable, with higher extracting ratio of the active components.
9.Study on the quality standards for Zhixuan Granule
Hongmei WEN ; Wei LI ; Aihua ZHANG ; Guoping PENG ; Zhengxin ZHANG
Chinese Traditional Patent Medicine 1992;0(06):-
Objective: The quality standards for Zhixuan Granule (Rhizoma Alismatis, Rhizoma Atractylodis Macrocephalae, etc.) were studied. Methods: The TLC methods for identification of Rhizoma Alismatis、 Rhizoma Atractylodis Macrocephalae were established. A simple HPLC was established for the determination of 23-acetate alisol B. The mobile phase was acetonitrile-water(70∶30). UV detecting wavelength was at 208nm. Results: Rhizoma Alismatis and Rhizoma Atractylodis Macrocephala could be detected. 23-acetate alisol B showed a linear relationship at the concentration range of 99~1388.8ng, r=0.9999. The average recovery was 103.05% and RSD was 2.41%(n=6). Conclusion: This method is suitable for the quality control of Zhixuan Granule.
10.Clinical value of catheter in pancreatic duct for prevention of post-EPBD pancreatitis
Yiyi HU ; Guoping DU ; Peng WANG ; Guohua LI ; Yunzheng XIE
Chinese Journal of Digestive Endoscopy 2015;(5):296-299
Objective To evaluate catheterization in pancreatic duct before endoscopic papillary bal-loon dilation (EPBD)to prevent pancreatitis after EPBD.Methods Forty-three patients with normal serum amylase levels,diagnosed as having bile duct stones,underwent EPBD.Twenty-three were assigned to experi-mental group,where catheters(ERCP imaging tube)were placed in pancreatic duct before EPBD,then the pa-pillary balloon was expanded to 10 mm.Twenty were assigned to control group where eight-millimeter-diameter papillary balloon was used to remove the stones.The serum amylase levels before EPBD,6 hours and 24 hours after EPBD,the incidence of pancreatitis and high serum amylase levels associated with EPBD,as well as the mean time and success rate of removing the stones of the two groups were compared.Results Post-EPBD pan-creatitis occurred in one patient in experimental group (4.35%),and seven in control group (35.00%), which was significantly different(P <0.05).Meanwhile,the mean levels of serum amylase 6 h and 24 h after EPBD in the experimental group were (102.61 ±98.99)U /L and (60.35 ±26.18)U /L respectively,lower than those in the control group (398.25 ±259.32)U /L and (230.50 ±281.31)U /L(P <0.05).After the papillary balloon was expanded to 10 mm in experimental group,the mean time of removing stones was (10.43 ±2.27)min,which was shorter than that of control group (17.90 ±4.49)min (P <0.05).Stone-re-moving rate of two groups had no difference and they all succeeded one time.Conclusion Placing catheter in pancreatic duct before EPBD to prevent pancreatitis after EPBD makes it easier to remove stones in shorter op-eration time.It can prevent pancreatitis and high amylase blood disease after EPBD.