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.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.
5.Process of Removing Bacterial Endotoxins by Ultrafiltration from Dextran 40 Injection
Xinglei ZHI ; Cunyu LI ; Hongyang LI ; Yang LU ; Guoping PENG
Herald of Medicine 2014;(7):922-925
Objective To study the process of removing bacterial endotoxins by ultrafiltration technology in dextran 40 injection. Methods Dextran 40 solution was ultrafiltrated by 100,200,and 300 kDa aperture ultrafiltration membranes with composite, PES and PVDF materials. In order to optimize ultrafiltration process,the content of effective component and endotoxins were detected by HPLC and kinetic-turbidimetry,respectively,and the change of particle size distribution in dextran 40 solution was analyzed before and after ultrafiltration. Results The transmittance of dextran 40 was close to the same MWCO and different membrane material. When MWCO reached 300 kDa,the transmittance was above 91%,which met the requirement of filtration. The endotoxin removal rates by 100-300 kDa composite ultrafiltration membranes were more than 99%. But the endotoxin removal rates of both of PES and PVDF membranes were less than 40%,which were unable to guarantee the removal efficiency of the endotoxin in dextran 40 solution. The particle size declined after ultrafiltration by 300 kDa composite membrane, and level of the insoluble particles decreased. Conclusion The 300 kDa composite ultrafiltration membrane can effectively remove endotoxin in dextran 40 solution with less main components loss. The material can meet requirements for producing dextran 40 injection.
6.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.
7.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.
8.Effect of local application of alendronate combined with tetracycline on the healing of replanted dog teeth after extended dry time
Lixing YIN ; Huawei XIE ; Chen CHEN ; Peng WANG ; Guoping WANG
Journal of Practical Stomatology 1995;0(04):-
0.05).The inflammatory resorption of root in experimental group was lower than that in the control(P
9.Study the application of macroporous resin combined with membrane in the refinement of traditional Chinese medicine
Guoping PENG ; Guoyuan ZHU ; Liwei GUO ; Lihua XU ;
Chinese Traditional Patent Medicine 1992;0(01):-
Objective: To study the application of macroporous resin combined with membrane in the refinement of traditional Chinese medicine. Methods: The extracts of single herbal drug and prescriptions were absorpted with macroporous resin, following by microfiltrated respectively, and then detected the extracts and analysized the quanity of effective components. Results: Through macroporous resin combined with membrane, the quantity of effective components could be improved significantly, and the method was very effective for refinement of traditional Chinese medicine. Conclusion: Application of macroporous resin combined with membrane has great prospect in the refinement of traditional Chinese medicine.