1.Inhibitory effects and mechanisms of snake venom tripeptide pENW on platelet adhesion.
Li BAI ; Wei-rong FANG ; Yi KONG ; Yun-man LI
Acta Pharmaceutica Sinica 2015;50(9):1107-1115
This study was designed to investigate inhibitory effects and possible mechanisms of snake venom tripeptide (pENW) on platelet adhesion in order to promote the development of a novel anti-platelet therapy. To study the inhibitory effects of pENW on platelet adhesion, washed platelets pre-incubated with pENW (116.5-466.2 μmol x L(-1)) were used to test the ability of platelet adhesion to fibrinogen. Effect of pENW on fibrin clot retraction was also tested. Effect of pENW on platelets viability was tested by MTT assay. Effect of pENW on reactive-oxygen species (ROS) levels of platelet was studied by flow cytometry assay. Calcium mobilization in Fura-2/AM-loaded platelets was monitored with a spectrofluorimeter. Cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP), thromboxane A2 (determined as its metabolite thromboxane B2) were measured using enzyme immunoassay kits. Akt, ERK and p38 phosphorylation were tested by Western blot. The results showed that pENW inhibited platelet adhesion and fibrin clot retraction in a concentration-dependent manner without cytotoxicity. Intracellular cGMP and cAMP in both resting and thrombin-activated platelets were increased by pENW. In addition, pENW attenuated intracellular Ca2+ mobilization and TXA2 production in platelets stimulated by thrombin. As shown by Western blot assay, Akt, ERK and p38 phosphorylation in thrombin-induced platelet were attenuated by pENW. However, inhibitory effects of pENW had nothing to do with ROS. Thus, pENW exhibited a significant inhibition on platelet adhesion to fibrinogen, which means pENW could block the first step of thrombosis as while as retard the more stable clot formation. The mechanisms of pENW on inhibition platelet adhesion might be related to instant regulations, such as protein kinases.
Blood Platelets
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drug effects
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Blotting, Western
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Calcium
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metabolism
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Cyclic AMP
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metabolism
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Cyclic GMP
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metabolism
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Flow Cytometry
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Phosphorylation
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Platelet Aggregation
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drug effects
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Reactive Oxygen Species
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metabolism
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Snake Venoms
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chemistry
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Thromboxane A2
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metabolism
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Thromboxane B2
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metabolism
2.Hemoprotective Effect of Rotating and Stationary Magnetic Field on Mice Receiving 5-Fluorouracil
Guo-li SONG ; Bai-miao JI ; Xiao-yun ZHANG
Chinese Journal of Rehabilitation Theory and Practice 2006;12(3):213-216
ObjectiveTo study the hemoprotective effects of rotating and stationary magnetic field(RSMF) in mice treated with 5-Fluorouracil(5-FU).MethodsThe BalB/C mice were randomly divided into control group and RSMF-treated group.The mice were injected with 5-FU,the dose were 150,180,210,250 mg/kg respectively. RSMF-treated group was exposed to RSMF for 1 h a time,twice a day during 30 consecutive days,and the magnetic intensity was 0.6 T.The survival rate and survival days during the 30 days were observed.7,10,14,21,28 days after injection,the peripheral blood cells were counted.On day 8,10 and 14,the number of bone marrow mononuclear cells(BMNC) and the forming ability of colony-forming unit-granulocyte/macrophage(CFU-GM) were measured.The pathological section of femur and the expression level of bone morphogenic proteins(BMPs) in bone marrow were evaluated.ResultsRSMF could increase the survival rate and survival days of mice treated with 5-FU,and induce an increase in hemoglobin concentration,white blood cell count(WBC),red blood cell count(RBC) and platelet number.Also,RSMF could increase the number of BMNC and improve the forming ability of CFU-GM on days 8~14.Furthermore,RSMF could improve the bone marrow angiogenesis and the expression level of BMPs.ConclusionRSMF have an obvious protective effect against chemotherapeutic injury,and it can accelerate the recovery of hematopoiesis and hematopoietic microenvironment in mouse bone marrow.
3.Genetics in different subtypes of ischemic stroke
Wen BAI ; Yun LI ; Zhizhong ZHANG ; Gelin XU
International Journal of Cerebrovascular Diseases 2013;21(5):369-373
Stroke is a class of complex diseases,and it is the result of the combined action of environmental and genetic factors.With the development of molecular biology techniques,a large number of candidate genes associated with stroke and susceptibility loci have been identified.This article reviews the recent progress in research on the genetics of different subtypes of ischemic stroke.
4.The assessment of levator ani muscle contractility in postpartum women by three-dimensional ultrasound
Lian XU ; Yun BAI ; Feifei LIU ; Qin LI ; Tao YING
Chinese Journal of Ultrasonography 2014;23(3):239-242
Objective To assess the contractility of levator ani muscle in postpartum female using pelvic floor three-dimensional ultrasound and to provide an effective imaging basis for the change of levator ani muscle contractility in postpartum female.Methods Totally 75 postpartum women (55 underwent spontaneous vaginal delivery and 20 underwent selective cesarean delivery) and 40 nulliparas were examined by pelvic floor three-dimensional ultrasound.The images were obtained at rest and at maximal levator ani muscle contraction.The sagittal hiatal length (L) on the two-dimensional sagittal images,the area of levator hiatus (A) and the circumference of levator hiatus (C) were measured on the three-dimensional images,and the difference value between rest and contraction were calculated to get the △L,△A,△C.Then the △L,△A,△C between different groups were compared.Results The △L,△A,△C in spontaneous vaginal delivery group and selective cesarean delivery group were smaller than those in nulliparas group (P <0.05),and there was no statistical difference between spontaneous vaginal delivery and selective cesarean delivery group (P > 0.05).Conclusions Three-dimensional ultrasound can effectively assess the the contractility of levator ani muscle,the levator ani muscle contractility of postpartum female was poorer than nulliparas,and between spontaneous vaginal delivery and selective cesarean delivery women there is no obvious difference.
5.Effects of Huangqi Guizhi Wuwu Decoction given by different administration methods on rats with frostbite and the mechanism.
Yanyan LI ; Yonghui WANG ; Yonggang ZHANG ; Yun BAI ; Ran ZHOU
Journal of Integrative Medicine 2010;8(2):181-5
To establish a rat model of frostbite and to evaluate the effects of different administration methods of Huangqi Guizhi Wuwu Decoction (HGWD), a compound traditional Chinese herbal medicine for warming meridians to disperse cold, on rats with frostbite.
6.Inhibitory effect of recombinant LIGHT-Fc gene on the proliferation of human esophageal squamous carcinoma cell line Eca109
Gang XIONG ; Wei WU ; Jun LI ; Kang YANG ; Yun BAI
Chinese Journal of Digestive Surgery 2008;7(4):307-309
Objective To investigate the inhibitory effect of recombinant LIGHT-Fe gene on the proliferation of human esophageal carcinoma cell line Eea109. Methods LIGHT-Fc expression vector was transfected into human esophageal squamous carcinoma cell line Eca109 by using DOTAP liposomal transfection reagents. The effects of LIGHT-Fc gene on the proliferation of esophageal carcinoma cell line Eca109 in vitro were detected by cell growth curve and MTr assay. Forty-five nude mice were equally divided into Eea109/Wt group, Eca109/neo group and Eca109/LIGHT group. Carcinogenesis and pathological expression of the esophageal carcinoma tissues were observed. Results The expressions of LIGHT receptors were detected in Eca109 cells. The proliferation of Eca109 cells was inhibited after trasfecting LIGHT-Fc gene into Eca109 cells. The numbers of tumors generated in Eea109/Wt group, Eca109/neo group and Eca109/LIGHT group were 12, 11 and 5, with statistical significance between Eca109/LIGHT group and the other two groups (X2 =6.652, 4.821, P <0.05). The result of histopatholagical examination indicated that the tissue necrosis appeared significantly in tumors derived from Eea109/LIGHT cells. Conclusions The growth of esophageal squamous carcinoma cell line Eca109 can be suppressed by LIGHT-Fc gene whether in vitro or in vivo.
8.The Role of Predictive Microbiology in Food Safety Risk Assessment
Jie-Yun HU ; Jie OU ; Bai-Lin LI ;
Microbiology 2008;0(09):-
With the development of the food industry in China,it has been found that food safety is becoming the biggest issue in the food manufacture and logistics. Accurate and timely to establish a risk assessment method in produce market is the challenge for food safety system. Predictive microbiology is a core early warning technology in the food safety risk assessment. According to the microorganism predicting model,the pathogen and spoilage microorganism's growth in food can be fast judgment in advance. And it plays an important part in controlling the growth of pathogen and the spoilage microorganism in food. This paper summarized the predictive microbiology model's establishment and the present research situation,and discussed the present situation and application of predictive microbiology in food safety risk assessment. The future trend of predictive microbiology in food safety risk assessment was prospected as well.
9.Construction and eukaryotic expression of human CD137-Fc chimeric molecule
Gang HUANG ; Wanling LI ; Man JIANG ; Yun BAI ;
Journal of Third Military Medical University 2003;0(24):-
Objective To construct eukaryotic expression plasmid of hCD137 Fc gene and express hCD137 Fc fusion protein with high biological activity. Methods PCR technique was employed to clone the human CD137 cDNA from a normal human activated T cells cDNA library, and then clone its extramembrane encoding region. The extramembrane sequence together with human IgG1 Fc cDNA were inserted into the eukaryotic expression plasmid pcDNA3. CD137 Fc gene was expressed transiently in 293T cells, and then CD137 Fc protein was purified by recombinated protein A affinity chromatography column. At last, the MW, purity and antigenicity of CD137 Fc were identified by sandwich ELISA, SDS PAGE and Western blotting, respectively. Results The ORF of CD137 Fc gene was coincident with what we expected. ELISA and SDS PAGE confirmed protein expression in 293T cells. Western blotting proved the antigenicity of the purified CD137 Fc protein. Conclusion We obtained a purified recombinated CD137 Fc protein with biological activity and the expected MW. This lays the foundation for further studies of CD137 such as its role in immune homeostasis and other biological functions.
10.Cloning of human LIGHT gene and expression of the cloned molecule on 293T cells
Man JIANG ; Gang HUANG ; Wanling LI ; Yun BAI ;
Journal of Third Military Medical University 2003;0(08):-
Objective To clone the full length cDNA of human LIGHT and to construct the recombinant eukaryotic expression plasmid pCI neo LIGHT for the stable expression on 293T cells. Methods Human LIGHT cDNA was cloned from a normal human activated T cell cDNA library phAD.CAD by PCR. After sequencing, LIGHT cDNA was inserted into plasmid pCI neo for the construction of the eukaryotic expression. The recombinant was transfected into 293T cells by electroporation. The expression of LIGHT on the surface of 293T cells was detected by flow cytometry after screening with G418. Results Sequencing confirmed that ORF of LIGHT gene was intact and right. Restrictive enzyme digestion proved that LIGHT gene was inserted into the recombinant plasmid of LIGHT pCI neo correctly. FACS analysis revealed that about 78.69% 293T cells expressed LIGHT protein on the cell surfaces at 3 months after screening with G418. Conclusion LIGHT gene has been cloned successfully, and a 293T cell line expressing LIGHT protein on its membrane surface has been obtained.