1.STUDIES ON THE CHARACTERISTICS OF A MODERATELY THERMOACIDOPHILIC IRON-OXIDIZING BACTERIVM
Microbiology 1992;0(06):-
A moderately thermoacidophilic iron-oxidizing bacterium,designated as strain MLY,was isolated from a coal spoil heap in China.The optimum of temperature for growth is 50℃~54℃.The optimum of pH is 1.2~1.4.The strain MLY is facultative autotroph and grows heterotrophically on yeast extract.It is able to oxidize ferrous iron(Fe 2+ ),pyrite(FeS 2),and elemental sulfur(S 0) autotrophically and mixotrophically in the presence of yeast extract.Autotrophic oxidation of elemental sulfur is relative weak.The comparison of ferrous iron and pyrite oxidation between strain MLY and A10 Thiobacillus ferrooxidans,strain indicated that MLY is one time faster than A10.
2.Angiogenesis and its regulation mechanism in S_(180) transplanted tumor of mice
Hui GUO ; Huiling YANG ; Qin ZHENG
Chinese Journal of Pathophysiology 2000;0(11):-
AIM: To investigate the angiogenesis in the process of sarcoma 180 (S_(180)) tumor transplantation and changes of regulator factors, and explore the possible mechanism. METHODS: The S_(180) transplanted tumor in the Km mouse was used to detect the tumor angiogenesis by immunohistochemical examination of FⅧ. The levels of VEGF (V) and endostatin (E) in serum and the homogenate of tumor tissue were measured by ELISA and EIA, and the correlation between tumor weight and microvessel count (MVC) and morphology in tumor was also analyzed by multiple ANNOVA method. RESULTS: MVC, the relative count of total vessels and relative total vessel area increased with the development of transplanted S_ 180 . VEGF level in tumor tissue were higher at the 10th and 15th day than the 5th day after tumor transplantation. Endostatin in the tumor tissue and serum both reached the highest level at the 15th day, V/E ratio did not changed in this process. Furthermore, MVC, average vessel area and relative total area had a significant correlation with tumor weight. CONCLUSION: MVC increases in the development of S_(180) transplantation tumor and is related with the tumor weight; the positive regulator of angiogenesis in the tumor tissue is up-regulated during tumor growth, and the regulators in the tumor tissue maintains a relative balance.
3.Progress in the study of drug-eluting intra-stent thrombosis
Zhifu GUO ; Xing ZHENG ; Yongwen QIN
Journal of Interventional Radiology 2006;0(08):-
Durg-eluting stent has been regarded as the milestone in the history of PCI for their efficiency in the prevention of coronary arterial restenosis after percutaneous coronary intervention. But unfortunately intra-stent thrombosis continues to be a serious complication of contemporary DES use. The incidence of drug-eluting stents thrombosis is at least not lower than that of bare metal stents at present. The clinical consequences of stent thrombosis are frequently catastrophic, including death in 40% to 50% of the cases or major myocardial infarction in 60% to 70%. Premature discontinuation of standard antiplatelet therapy is by far the most important predictor of stent thrombosis with DES and other predictors included renal failure, diabetes, bifurcation lesions, multiple lesions or multivessel disease, long stents, female, advanced age, stent underexpansion and residual stenosis etc. The delayed endothelialization may be the underling mechanism of DES thrombosis.
4.Research on reform of incorporating case analysis into pathophysiology teaching by many ways
Junxia LEI ; Zhenyu GUO ; Qin ZHENG
Chinese Journal of Medical Education Research 2003;0(04):-
To meet with the need for culivating high-quality medical talents,the new teaching mode of problem-based learning (PBL) is attracting a lot of attention. Pathophysiology, which bridges basic medicine courses and clinical medicine courses,is more suitable for implementing PBL teaching mode. The teaching mode of incorporating case analysis is used into pathophysiology teaching by many ways is studied and an ideal result has been achieved.
5.Establishment of chronic graft-versus-host disease models after allo-bone marrow transplantation in rats
Zhenyu GUO ; Junxia LEI ; Qin ZHENG
Chinese Journal of Tissue Engineering Research 2007;0(07):-
AIM: To investigate the feasibility of establishment for chronic graft-versus-host disease (cGVHD) model in rats after allo-bone marrow transplantation (allo-BMT), in order to provide premise conditions for further studying the immuno-regulation role of mesenchymal stem cell (MSC) on GVHD after allo-BMT. METHODS: This experiment was finished in Laboratory of Pathology and Pathophysiology in Sun Yat-sen University from April to September 2006.①Six-week-old male Fischer344 rats (RT1Al) were used as donors while six-week-old female Waster (RT1Au) rats were used as recipients.②Recipient rats were given water supplemented with gentamycin (320 mg/L) and erythromycin (250 mg/L) three days before BMT. On the day of transplantation, recipient rats received 8.0 Gy (60Co ?, 0.7 Gy/min) total body irradiation. Within 6 hours following the irradiation, recipient rats in BMT group were transplanted with 0.8?108 cells via tail vein injection, while rats in control group only received the same volume injection of phosphate buffer. Each group included 10 animals. Evaluation of common living status was monitored including daily diet, activity, stool and urine, fur and body mass. Shaved skin, liver and intestine tissues were also analyzed histologically. RESULTS: ①All rats in the control group died within 17 days following the irradiation and most of them died on day 11 or 12 post-transplantation, while BMT group had higher survival rate, in addition to three rats died on days 12, 16, 18 respectively, whereas others were all alive through 60 days expectation period.②Rats in the BMT group had no clear symptoms of acute GVHD, such as rapid weight loss and severe diarrhea, however, the weight growth in rats of the BMT group was quite slow. Furthermore, 1 month following BMT, depilation phenomenon was evident in the head and back of recipients, and then extended to abdominal part and extremity with the increase of time. Two months following BMT, skin follicular dropout and slight dermal mononuclear infiltration were found. Hepatic disease was characterized by portal tract lymphocyte infiltration, fibrous thickening and sclerosis of the bile duct wall. Small bowel specimens showed clear inflammatory cell infiltration (neutrophils, acidophils, macrophages) within lamina propria. CONCLUSION: ①The cGVHD model can be established through allo-BMT from F344 to Wistar rats.②The typical histological signs of cGVHD are evident in skin, liver and intestine tissues, among which hepatic sign is the most dominant including portal tract and bile duct mononuclear infiltration followed by fibrous thickening and sclerosis of the bile duct wall.
6.Role of endogenous calcitonin gene related peptide in stress-induced retinal cell apoptosis
Ya-qin, ZHANG ; Ji-hong, YANG ; Zheng, GUO
Chinese Journal of Experimental Ophthalmology 2011;29(3):206-208
Background Acute stress can provoke the apoptosis of retina cells and induce increasing expression of calcitonin gene related peptide(CGRP)in retina.However,the role of CGRP in pathology of the stressinduced apoptosis of the retina ceils is still elusive.Objective The aim of this study was to investigate the effects of endogenous CGRP on retinal cell apoptosis induced by stress of acute myocardial ischemia after coronary artery occlusion in rats. Methods The acute myocardial ischemia model was established by ligating the left anterior descending branch of coronary artery in 12 male Sprague-Dawley rats.The rats were randomized into CGRP8-37 injection group and normal saline injection group,6 rats 12 eyes for every group.CGRP8-37(10-7 mol/L),a specific antagonist of CGRP receptor,was intravenously injected in CGRP8-37 group by caudal vine at 15 minutes prior to the coronary artery occlusion,and the equivalent amount of normal saline was used at the same fashion in normal saline group.The retinal samples of the rats were collected at 3 hours after coronary artery occlusion for TUNEL staining and caspase-3 activity detection respectively. Results The cellular displacement was observed in inner and outer nuclear layer,and vacuolar degeneration of retinal ganglion cells was found in the coronary artery occlusion animals.The total apoptosis index of retinal cells in CGRP8-37 group was significantly higher than that in normal saline group (42.8%±2.8% vs 37.5%±2.9%,t=-3.244,P<0.01).The retinal capase-3 activity was significantly enhanced in the CGRP8-37 group compared with saline group(11.3±3.1 fold vs 4.9±1.2 fold,t=-4.603,P<0.01)at 3 hours of coronary artery occlusion.Conclusion The results suggest that the endogenous CGRP may play an anti-apoptotic role in the stress.induced retinal cell injury.
7.Solution space of pharmacokinetics and its application on mice brain with 18F-FECNT
Guo-xian, CAO ; Zheng-ping, CHEN ; Xing-qin, ZHOU
Chinese Journal of Nuclear Medicine 2011;31(4):255-258
Objective To forward the concept of solution space of pharmacokinetics for studying radiophannaceutical distributions in animal models. Methods On the basis of special solutions of differential equations of pharmacokinetics, the solution space was established using the characteristics of linearly independent particular solutions and used to express the pharmacokinetics of pharmaceuticals in vivo. 0. 2 ml (7.4 MBq) 2β-carbomethoxy-3β- (4-corophenyl)-8-(2-18F-fluoroethyl) nortropane (18F-FECNT) was injected through tail vein into normal mice. The mice were sacrificed by decapitation at 5, 15, 30, 60, 120 and 180 min post-injection. Brain tissues were removed and weighed, and radioactivity was counted with the γ-counter. The solution space theory was used to study pharmacokinetics of 18F-FECNT in brain tissues of mice. Results The result showed that all solutions of pharmacokinetics models, based on differential equations, were included in the solution space. The solution of any organ or tissue could be linearly expressed by bases of the solution space. When the dimension number of the solution space was no more than 3, the solution could be directly expressed with coordinate picture. By this rule in our theory, the quantity of 18F-FECNT in brain tissues of mice changed with time, which was accorded with the experiment. The coordinates of striatum, frontal cortex, temporal cortex, occipital cortex, parietal cortex, hippocampus and cerebellum in the solution space were ( 10.13, 1.49), (4.27, 0. 84), (4.48, 0.81 ), (2.89, 0.98), (3.65, 0. 83),(3.55, 0. 98) and (2.03, 1.25 ), respectively. Conclusion The theory of solution space could be used to study pharmacokinetics of 18 F-FECNT in mice brain.
8.Based on the macromolecules in traditional Chinese medicine exploring the material basis and mechanism of the analgesic effect of Shaoyao Gancao Decoction
Yuan GAO ; Qin GUO ; Huan-huan WANG ; Ying-ying DONG ; Ning ZHAO ; Zheng-shen YAN ; Yu-qin YANG ; Dong BAI
Acta Pharmaceutica Sinica 2023;58(5):1138-1148
In order to study the analgesic effect of Shaoyao Gancao Decoction, this paper discussed material basis and mechanism from the perspective of macromolecules in traditional Chinese medicine. Inspired by the phenomenon of turbidity after boiling Chinese medicine, this experiment took Shaoyao Gancao Decoction as the research object to study the formation process of precipitation during boiling. The results showed that aggregates with a certain shape were formed in the solvent during the boiling process, and the precipitate was obtained by standing and centrifuging. Analysis found that the precipitation was mainly composed of small molecules such as paeoniflorin, albiflorin, liquiritin, glycyrrhizic acid, isoliquiritin and gallic acid, and macromolecules such as protein and polysaccharide. The composition of precipitate was consistent with that of Shaoyao Gancao Decoction, but the analgesic effect of Shaoyao Gancao Decoction after removing the precipitate was significantly reduced. Based on these results, we isolated small molecular compounds, polysaccharides and protein from Shaoyao Gancao Decoction and their contents are 60.4, 700.7 and 207.2 mg·g-1 respectively. We get the ratio, polysaccharide: small molecule = 11.6∶1, protein: small molecule = 3.4∶1, the precipitate is prepared in the state of boiling. The characterization results showed that the particle size of the precipitate will change significantly after co-heating, and the content determination results showed that the content of the six small molecular compounds which was free in solvent was significantly reduced after the formation of the precipitate. The acetic acid writhing experiment proved that the precipitate has a good analgesic effect, and effectively reduced the levels of inflammatory factors prostaglandin E2 and nitric oxide, and increased the level of anti-inflammatory factor interleukin-10. These results proved that the precipitate in Shaoyao Gancao Decoction is an important material basis for analgesic effect, and macromolecules such as protein and polysaccharide are the main components of the precipitate. The study of macromolecules in the precipitate of Shaoyao Gancao Decoction not only provides new ideas and methods for elucidating the pharmacodynamic material basis of Shaoyao Gancao Decoction, but also provides a reference for analyzing the scientificity of traditional decoction.
10.Differential regulation of SREBP 1 c/cm on transcriptional activity and expression of PERK promoter
Qin HU ; Yu MAO ; Jialing LU ; Weiwei XIE ; Wei ZHENG ; Fengjin GUO
Basic & Clinical Medicine 2017;37(2):162-168
Objective To investigate the effect of sterol regulating element binding protein (SREBP1c) and its ac-tive form (SREBP1cm) on human protein kinase R-like endoplasmic reticulum kinase (PERK).Methods Re-porter victors of PERK promoter and its truncations were constructed with pGL 3-basic and co-transfected with internal reference pRL-SV40 into cell and luciferase activity was detected .pcDNA3.1 ( -)-SREBP1c or pcDNA3.1 ( -)-SREBP1cm was co-transfected with PERK promoter transcriptional activity core regions and the detection of dual -lu-ciferase reporter gene was used to analyze the regulation of SREBP 1c/1cm on PERK promoter transcriptional activity . The expression level of PERK mRNA and protein were detected by RT-PCR and Western blot .Results PERK pro-moter and truncations were successfully constructed into pGL 3-basic, and PERK promoter core area of transcription-al activity had determined;Dual-luciferase report gene showed that SREBP 1c inhibited PERK promoter transcrip-tional activity and SREBP1cm promoted PERK promoter transcriptional activity .RT-PCR and Western blot showed that SREBP1c decreased PERK mRNA and protein expression , but SREBP1cm increased PERK mRNA and protein expression, which was consistent with the detection of dual-luciferase report gene .Conclusions SREBP1c and SREBP1cm have a opposite regulation effect on PERK promoter transcriptional activity and its expression .