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
;
drug effects
;
Blotting, Western
;
Calcium
;
metabolism
;
Cyclic AMP
;
metabolism
;
Cyclic GMP
;
metabolism
;
Flow Cytometry
;
Phosphorylation
;
Platelet Aggregation
;
drug effects
;
Reactive Oxygen Species
;
metabolism
;
Snake Venoms
;
chemistry
;
Thromboxane A2
;
metabolism
;
Thromboxane B2
;
metabolism
2.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.
3.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.
4.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.
5.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.Expression of angiopoietin-like proteins for animal breeding: a review.
Weiwei FU ; Yun MA ; Ningbo CHEN ; He LI ; Yueyu BAI
Chinese Journal of Biotechnology 2015;31(11):1567-1578
Angiopoietin-like proteins are a family of proteins that are closely related to lipid, glucose and energy metabolism, as well as angiogenesis. To date, eight Angptls have been discovered, namely Angptl1 to Angptl8 that play key roles in metabolic regulation and marker assisted selection. In this review, we summarized current progress on the structure, signaling pathways, upstream regulatory genes and metabolic network of Angptl1-8. Finally, in combination with our work, the status and problems of animal breeding as well as the future prospects for Angptls were discussed.
Angiopoietins
;
genetics
;
metabolism
;
Animals
;
Breeding
;
Energy Metabolism
;
Gene Regulatory Networks
;
Glucose
;
metabolism
;
Lipid Metabolism
;
Metabolic Networks and Pathways
;
Signal Transduction
9.Promoting effect of p75NTR receptor overexpression on oxidative stress injury in human retinal pigment epithelium cells
Yun, QI ; Yujing, BAI ; Xiaoxin, LI ; Xuan, SHI
Chinese Journal of Experimental Ophthalmology 2016;34(1):17-23
Background Choroidal neovascularization (CNV) is the primary pathogenic cause of many fundus diseases.Oxidative stress injury of retinal pigment epithelial (RPE) cells plays important role in angiogenesis of choroid new blood vessels.Oxidative stress injury can active p75NTR receptor, a member of tumor necrosis factors family,resulting in the proliferation of vascular endothelial cells.However, the mechanisms of vascular endothelial cell proliferation remain unclear.Objective This study was conducted to investigate the effect of p75NTR overexpression on CNV and the relative mechanism.Methods The ARPE-19 cell line was used in this study.RPE cells were transfected with p75NTR receptor overexpressed plasmid, and untransfected cells served as the control group.The transfected results were verified by reverse transcription-PCR and Western blot assay.Viability of the cells over time was determined in the p75NTR receptor plasmid transfected group by using BrdU assay.The percentage of apoptotic cells was detected by flow cytometry using Annexin V-FITC/PI fluorescence staining.The percentage of reactive oxygen species (ROS) expression in the cells was detected by using H2 DCFDA fluorescence and flow cytometry.Mitochondrial membrane potential and cytochrome C expression were examined under the confocal microscope.The protein expressions of cleaved caspase-3, Fas and VEGF were determined by Western blot assay.Results The relative expression level of p75 NTR receptor mRNA was (6.11 ±0.77) times higher than that of the control group, and relative expression level of p75NTR receptor protein in the cells in the p75NTR receptor plasmid transfected group was (7.42±0.48) times higher than that in the control group (t=11.49 and 23.17 ,both at P<0.01).The absorbency values of the p75NTR receptor plasmid transfected group were (93.12±0.56) % , (86.30±0.66) % , (72.53-±0.86) % and (60.77 ±2.81) % in 12,24,36 and 48 hours after plasmid transfection, which were significantly lower than 100% in the control group, and the apoptotic percentages were evidently higher than that in the control group (all at P<0.05).The relative fluorescence intensity of ROS fluorescence in the p75NTR receptor plasmid transfected group was 2.4 times higher than that in the control group,showing significant difference (t=16.45, P<0.01).The positive expressing rate of mitomarker (mitochondrial membrane potentials) was 100% in the control group and (37.30± 2.06)% in the p75NTR receptor plasmid transfected group, with significant difference between them (t =57.71,P<0.01).The fluorescence intensity of cytochrome C expression was elevated in the p75NTR receptor plasmid transfected group compared with the control group.Compared with the control group,the expressing levels of cleaved caspase-3 ,Fas and VEGF165 proteins in the cells were significantly raised in the p75NTR receptor plasmid transfected group (all at P<0.01).Conclusions Overexpression of p75NTR receptors in RPE cells leads to mitochondrial damage and cellular apoptosis and the secretion of VEGF protein, which sequentially promote CNV.P75NTR receptor may be another important regulation pathway in RPE oxygen damage.
10.Major assessment study and practice based on protecting teaching quality
Xiaojie ZHANG ; Li BAI ; Changhai YUN ; Qingdong LUO ; Dan XIN
Chinese Journal of Medical Education Research 2015;(3):248-251
The major assessment is the key link of the applied undergraduate education quality guarantee system. According to the spirit of the Ministry of Education, The Qiqihar Medical University developed the internal major assessment study and founded 8 first grade indexes and 26 second level indexes including educational idea, teaching staff, major construction. The university also established the major evaluation system, monitor and improve the university's teaching quality. This system makes sense to the establishment and improvement of undergraduate teaching quality guarantee system and has attained great achievement in the building of teaching staff, major construction, teaching environ-ment and teaching idea. Also the school has rectified the problems, making the work more perfect and the teaching better and better.