1.Antiarrhythmic effect of TJ0711.
Xiao-Jing ZHANG ; Jun QIU ; Gao LI
Acta Pharmaceutica Sinica 2014;49(3):419-426
To study the antiarrhythmic effect of the newly developed alpha/beta-blocker TJ0711, a variety of animal models of arrhythmia were induced by CaCl2, ouabain and ischemia/reperfusion. Glass microelectrode technique was used to observe action potentials of right ventricular papillary muscle of guinea pig. The onset time of arrhythmia induced by CaCl2 was significantly prolonged by TJ0711 at 0.75, 1.5 and 3 mg x kg(-1) doses. TJ0711 (1.5 and 3 mg x kg(-1)) can significantly shorten the ventricular tachycardia (VT) and ventricular fibrillation (VF) duration, the incidence of VF and mortality were significantly reduced. On ischemia-reperfusion-induced arrhythmic model, TJ0711 (0.25, 0.5, 1 and 2 mg x kg(-1)) can significantly reduce the ventricular premature contraction (PVC), VT, VF incidence, mortality, arrhythmia score with a dose-dependent manner. At the same time, rats serum lactate dehydrogenase (LDH) and creatine kinase (CK) activities decreased significantly by TJ0711 (1 and 2 mg x kg(-1)). Ouabain could cause arrhythmia in guinea pigs, when TJ0711 (0.375, 0.75, 1.5 and 3 mg x kg(-1)) was given, the doses of ouabain inducing a variety of arrhythmia PVC, VT, VF, cardiac arrest (CA) were significantly increased with a dose-dependent manner. In the TJ0711 0.1-30 micromol x L(-1) concentration range, guinea pig right ventricular papillary muscle action potential RP (rest potential), APA (action potential amplitude) and V(max) (maximum velocity of depolarization) were not significantly affected. APD20, APD50 and APD90 had a shortening trend but no statistical difference with the increase of TJ0711 concentration. TJ0711 has antiarrhythmic effect on the sympathetic nerve excitement and myocardial cell high calcium animal arrhythmia model. Myocardial action potential zero phase conduction velocity and resting membrane potential were not inhibited by TJ0711. APD20, APD50 and APD90 were shortened by TJ0711 at high concentration. Its antiarrhythmic action mechanism may be besides the action of blocking beta1 receptor, may also have a strong selective blocking action on alpha1 receptor and reducing intracellular calcium concentration.
Action Potentials
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drug effects
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Adrenergic alpha-Antagonists
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administration & dosage
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pharmacology
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Adrenergic beta-Antagonists
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administration & dosage
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pharmacology
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Animals
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Anti-Arrhythmia Agents
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administration & dosage
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pharmacology
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Arrhythmias, Cardiac
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blood
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chemically induced
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etiology
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pathology
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physiopathology
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Calcium Chloride
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Creatine Kinase
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blood
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Dose-Response Relationship, Drug
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Female
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Guinea Pigs
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Heart Ventricles
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cytology
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Lactate Dehydrogenases
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blood
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Male
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Myocardial Reperfusion Injury
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complications
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Myocytes, Cardiac
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drug effects
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physiology
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Ouabain
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Papillary Muscles
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cytology
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Phenoxypropanolamines
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administration & dosage
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pharmacology
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Random Allocation
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Rats
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Rats, Sprague-Dawley
2.Duction of immunoincompetence of T cells to oxidized-low density lipoprotein in vitro by CTLA4Ig
Yunling XIAO ; Haiqing GAO ; Jianhua ZHANG ; Cai ZHANG
Chinese Journal of Microbiology and Immunology 2008;28(3):244-249
Objective To induce the immunoincompetence of T cells to oxidized-low density lipoprotein(ox-LDL)in vitro,in order to prevent immune injuries in atherosclerosis(AS)and to find new strategies to prevent AS.Methods Monocytes were separated from peripheral blood to induce dendritic cells (DC).DCs were treated with LPS(30 ng/m1),ox-LDL(10μg/m1)and LDL(10μg/m1)for 48 h,respectively.Then DCs were mixed with allogeneic T lymphocytes to earry out mixed lymphoeytes reaction (MLR).CTLA4Ig in different concentrations was added into the MLR of ox-LDL group.MTr method was used to assay the proliferation of T cells.The CD25 expression and apoptosis of T cells in MLR were tested by flow cytometry.And the excretion of IL-2,IFN-γ and IL-4 were assayed by ELISPOT method.Results SI of the ox-LDL group was higher than that of the LDL group significantly(DC:T=1:5,1.6717±0.3152vs 1.4250±0.2874.P<0.05;DC:T=1:10,1.5458±0.2748 vs 1.3352±0.2991,P<0.05),and CTLA4Ig inhibited the SI of the ox-LDL group in dose-dependence(CTLA4Ig 1.25μg/ml,0.96±0.30 vs μg/ml 1.29±0.28 vs 1.64±0.33 P<0.05).CTLA4Ig caused the decrease of CD25 expression(CTLA4Ig 1.25 μg/ml,11.26±0.58 vs 14.25±1.02,P<0.05;CTLA4Ig 10μg/rnl 8.42±0.45,P<0.01)and induced apoptosis of T cells in MLR(CTLA4Ig 1.25μg/ml,12.54±3.69 vs 6.09 4-2.24,P<0.05;CTLA4Ig 10μg/ml,26.87±5.06 VS 6.09±2.24,P<0.01).CTLA4Ig caused the decrease of ELISPOT counts of IL-2(CTLA4Ig 1.25μg/ml,386±42 VS 534±54,P<0.05;CTLA4Ig 10μg/rnl,230±27 VS 534±54,P<0.01)and IFN-γ(CTLA4Ig 1.25μg/ml,445±48 VS 672±46,P<0.05;CTLA4Ig 10μg/ml,193±39 VS 672±46,P<0.01),while that of IL-4 increased(CTLA4Ig 1.25μg/ml,401±32 VS 332±41,P<0.05;CTLA4Ig 10μg/ml,453±57 VS 332±41,P<0.05).Conclusion CTLA4Ig can induce T cens immunoin competence to ox-LDL in vitro by inhibiting T cells activation,inducing T cells apoptosis and TH 1/TH2 immune deviation.
3.Effect of dexmedetomidine on myocardial injury induced by renal ischemia-reperfusion in rats
Li ZHANG ; Yong ZHANG ; Xiao TANG ; Tianqin GAO ; Yaoqi WANG
Chinese Journal of Anesthesiology 2014;34(8):1017-1019
Objective To evaluate the effect of dexmedetomidine on myocardial injury induced by renal ischemia-reperfusion (I/R) injury in rats.Methods Twenty-four male Wistar rats,weighing 280-300 g,were randomly divided into 3 groups (n =8 each):sham operation group (group S),group I/R and dexmedetomidine group (group Dex).Renal ischemia was induced by occlusion of bilateral renal arteries for 45 min followed by reperfusion in I/R and Dex groups.At 20 min before ischemia,dexmedetomidine 50 μg/kg was injected intraperitoneally in group Dex,and the rest procedures were similar to those previously described in group I/R.The rats were sacrificed at 24 h of reperfusion and myocardial specimens were obtained for determination of malondialdehyde (MDA) content and superoxide dismutase (SOD) activity.The apoptosis in cardiomyocytes was examined by flow cytometry.Apoptosis index was calculated.The expression of Bcl-2 and Bax was detected by immunohistochemistry,and Bcl-2/Bax ratio was calculated.Results Compared with group S,apoptosis index and MDA content were significantly increased in I/R and Dex groups,Bcl-2/Bax ratio was decreased in group I/R,and Bcl-2/Bax ratio was increased in group Dex.Compared with group I/R,apoptosis index and MDA content were significantly decreased,and SOD activity and Bcl-2/Bax ratio were increased in group Dex.Conclusion Dexmedetomidine can attenuate myocardial injury induced by renal I/R in rats,and the mechanism may be related to inhibited apoptosis in cardiomyocytes and reduced lipid peroxidation.
4.CTLA4Ig induces immune tolerance of T cells to oxidized-low density lipoprotein in vitro
Yunling XIAO ; Haiqing GAO ; Jianhua ZHANG ; Cai ZHANG
Chinese Journal of Pathophysiology 2000;0(12):-
AIM: Recently,it is widely accepted that atherosclerosis(AS) is an auto-immune related disease and the oxidized-low density lipoprotein(ox-LDL) is the most important AS-related antigen.In order to prevent immune injuries in AS and find new strategies to prevent AS,the immune tolerance of T cells to ox-LDL in vitro was induced in this study.METHODS: Human monocytes were separated from peripheral blood to induce dendritic cells(DCs).DCs were treated with LPS(30 ?g/L),ox-LDL(10 mg/L) and LDL(10 mg/L) for 48 h.Then DCs were mixed with allogenic T lymphocytes to carry out mixed lymphocytes reaction(MLR).CTLA4Ig in different concentrations was added in the MLR of ox-LDL group.MTT method was used to assay the proliferation of T cells and expressed in stimulation index(IS).The CD25 expression and apoptosis of T cells in MLR were tested by flow cytometry.The excretion of IL-2,IFN-? and IL-4 was assayed by ELISpot method.RESULTS: SI in ox-LDL group was higher than that in LDL group significantly(P
5.Analysis on macula injury caused by laser
Yan, ZHANG ; Yan, CAI ; Xiao-Ling, ZHANG ; Yong-Xin, GU ; Xiao-Wei, GAO ; Yun, XIAO
International Eye Science 2016;16(6):1176-1179
?AIM: To discuss the effect of laser exposure on visual acuity and macula.?METHODS: Retrospective and consecutive case series. A retrospective analysis of 11 patients (11 eyes) with laser retinal injury was carried out from January 2014 to June 2015 in Ophthalmology Department of No. 474 Hospital of Chinese PLA. All individuals underwent visual acuity, best corrected visual acuity ( BCVA ) , and spectral-domain optical coherence tomography ( SD-OCT) for macular at first visit, and fundus fluorescein angiography ( FFA ) , visual field, and multifocal electroretinogram ( mf ERG ) were perform if necessary. Symptomatic therapies, supportive therapies and pars plana vitrectomy ( PPV ) were performed depended on the patient’s condition. The patients were followed-up at 1, 3 and 6mo after the first visit, and patients were undertaken visual acuity, BCVA, macular SD-OCT and so on.?RESULTS: Eight patients ( 73%) were under 18 years old and all patients were young males, who were injured by laser pointers when playing. Three patients ( 27%) over 18 years old were injured accidentally at work. Ten (91%) patients’ BCVA were ≤0. 3, while one ( 9%) patient’s BCVA was higher ≥0. 3. Full-thickness macular holes ( the diameter 224-519 μm ) were detected in 10 patients (91%), while sub-foveal RPE changes and IS/OS injury in 1 patient ( 9%) . Macular hole with traction or cystoid edema in 6 eyes (55%) were received PPV, while the other 5 eyes ( 4 eyes with stable macular hole and 1 eyes with RPE injury ) received conservative treatment. Macular hole closed successfully in 1 eye ( 17%) after PPV, while macular hole in the other 5 eyes ( 83%) were stable after PPV of which the cystoid edema faded. The 4 patients with macular hole and 1 patient with RPE injury were stable during follow-up period. However, the BCVA in all patients had no significant improvement at end.?CONCLUSION: Exposure to laser devices could lead to severe macula injury that could reduce central vision, which is permanent.
6.In vitro study of type Ⅰ intron-mediated dual reporter gene imaging for carcinoembryonic antigen
Yajing ZHANG ; Jizheng CHEN ; Xuemei GAO ; Xue HU ; Xiao ZHANG ; Jiaqian LIANG ; Zairong GAO
Chinese Journal of Nuclear Medicine and Molecular Imaging 2015;35(4):298-302
Objective To develop a specific trans-splicing intron ribozyme type Ⅰ-mediated dual reporter gene system (Rib53-Fluc-tk) for targeting CEA.Methods The novel CEA-targeting trans-splicing ribozyme with the downstream reporter system (Rib53-Fluc-tk) was constructed by genetic engineering technology.The trans-splicing reaction product was evaluated using the 131I-5-iodo-2'-fluro-l-beta-D-arabinofuranosy-luracil (FIAU) cellular uptake rates and the bioluminescence.Two-sample t test,the analysis of variance and the least significant difference (LSD) t test was performed for data analysis.Results The sequence of Rib53-Fluc-tk was proved by gene-sequencing test.Human MCF-7 breast cancer cells showed a high ratio of firefly luciferase/renilla luciferase (0.64±0.10,n =4).A 520 bp band of product existed,which matched with the predicted size using RNA from cells transfected with Rib53-Fluc-tk in MCF-7.Signals were detected by bioluminescence in human embryonic kidney 293T cells co-transfected with Rib53-Fluc-tk and pCDNA3.1-CEA.The labelling rate of 131I-FIAU was (64.02±4.79)% (n =3).The radiochemical purity was (95.96± 1.07)% (n=3),and the stability of the radiocompound remained high in human serum at least for 24 h.The uptake of 131I-FIAU in 293T cells transfected with Rib53-Fluc-tk was (0.31±0.01)% (n=4),while it increased with the incubation time in 293T cells co-transfected with pCDNA3.1-CEA and Rib53-Fluc-tk and reached (1.40±0.06)% at 4.5 h (F=1 007.29,t=136.34,both P<0.01).Conelusions A novel and specific reporter gene in the cellular level was established.Taking advantage of trans-splicing reaction of the ribozyme,it could improve the specificity of the reporter gene imaging.
7.The involvement of outward potassium currents in methamphetamine-induced hippocampal neuron damage in fetal rat
Lei JIANG ; Jun WANG ; Rong GAO ; Hang XIAO ; Jinsong ZHANG
Chinese Journal of Emergency Medicine 2013;22(11):1229-1234
Objective To investigate the effects of methamphetamine (Meth) on the outward K+ currents and elucidate the role of outward K+ channels in Meth induced hippocampal neuron damage.Methods Hippocampal neurons were harvest from 18-day-old embryonic rats and were divided into two groups:the control group and the Meth treated group.Both of 4-AP and TEA sensitive K+ currents were recorded after the treatment of Meth by performing the whole cell patch clamp.Furthermore,the MTT and TUNEL assays were performed to evaluate the effects of K+ channel on hippocampal neuron damage mediated by Meth.For statistical comparison,One-way ANOVA and LSD multiple comparison test or t-test was used.P-value < 0.05 was considered to be statistically significant.Results The density of 4-AP sensitive K+ channel currents in Meth treated group [(120.1 ± 19.6) pA/pF,n =7] were significantly increased when compared with control group [(87.4 ± 12.5) pA/pF,n =10,P <0.01] and the increments of the currents induced by Meth was dose dependent.The MTT data showed that the cell viability was obviously decreased in Meth treated group (48.72 ± 4.38) % relative to the control group (100.07 ± 3.36) %.Moreover,application of K+ channel antagonist,4-AP (61.39 ± 3.15)%,and the high K+ solution (78.25 ± 9.42) % substantially enhanced the cell viability.The TUNEL assay showed there were protective effects of 4-AP and the high K+ solution against neuron damage observed during cells exposed to Meth.Conclusions The increments of 4-AP sensitive K+ channel currents induced by Meth might be involved in hippocampal neuron damage.
8.Survey and analysis of study attitude and current situation of medical English study among medical students of long schooling
Lei HUANG ; Jing ZHANG ; Yuanyuan XIAO ; Minfei QIANG ; Yuan GAO
Chinese Journal of Medical Education Research 2014;(3):298-301
Objective To understand the attitude and current situation of medical English stud y as well as its relevant factors among long schooling medical students so as to provide first hand information for constructing students-centered medical English teaching model. Methods A self-de-signed questionnaire including basic information of students, attitude and current situation of medical English students was given to 134 seven or eight year program clinical medical graduates from grade 2006 to grade 2008 in Tongji University. Questionnaires were collected timely and an-alyzed with SPSS 19.0 and results were described by percentage. Results Totally 132 copies of questionnaire were recovered with an recovering rate of 98.51%. 56.82%(75/132) students had interest in medical English study and 71.97%(95/132)students had a will to go abroad for learning exchange. Main pur-poses for students to learn medical English were ‘professional literature reading’(68.94%,91/132),‘SCI papers writing’(59.09%,78/132)and ‘international communication’(58.33%, 77/132). Main influencing factors of medical English study were ‘boring teaching methods ’ ( 45 . 45%, 60/132 ) ,‘difficult medical English’(41.67%,55/132) and ‘insufficient teaching time’(40.91%,54/132).Conclusions Medical students with long schooling have demand for medical English study;however, most of them have some difficulties in practical application. Measures should be taken from three as-pects including students, teachers and curriculum setting to improve students' medical English.
9.Magnetic resonance imaging changes and analysis of related factors after treatment in childhood hepatolenticular degeneration
jianming, ZHANG ; xiao-qing, LIU ; yu, GAO ; mei-xian, WANG
Journal of Applied Clinical Pediatrics 2004;0(12):-
Objectives To observe the changes of magnetic resonance imaging(MRI) during the course of treatment in hepatolen-ticular degeneration (HLD) and to evaluate its related factors.Methods Sixty - three patients with HLD received routine SE sequence MRI of brain and liver.Twenty - two patients with abnormal MRI in 42 patients and each of them had 2-4 times of serial MRI ex-aminations at interval of 1.0- 1.5 year.Results Ten patients had lesion in both brain and liver in 22 patients. Nine patients only in brain, 3 patients in liver.The major lesions disappear or decrease after rational treatments. There were only slight or no changes of MRI abnormalities in patients receiving treatments or age of patients was over 15 year old. Abnormal MRI findings shown again after stopped treatments over 2 months. In such cases, the clinical and MRI improvements were slow.The rate of clinical and MRI improvement in patients with adequate treatment were markedly higher than patients with inadequate treatment.Conclusions Liver and brain lesion will show in MRI disappear after adequate treatment;There are only slight or no change or showing again in MRI abnormalities in pa-tients with inadequate treatments compared with poor clinical improvement. MRI is beneficial to understanding therapeutic effect and prognosis of HLD.
10.The effects of four dental metal crowns on magnetic resonance imaging
Lan GAO ; Yinghuai ZHANG ; Yunmin LIAN ; Tiepeng XIAO
Journal of Practical Stomatology 2014;(4):472-476
Objective:To observe the artifacts produced by dental metal crown made from different materials on magnetic resonance imaging (MRI).Methods:Mental crows made from Co-Gr,Ni-Gr,low-Ti alloy and Pure-Ti were respectively fabricated for upper right second premolar of a ripe crossbreed dog.The 4 different casting crowns were respectively put on experimental tooth and head MRI scan was carried out with 4 sequences of 1.5 T and 6 sequences of 3.0 T MRI respectively.The existence and extent of the arti-facts were assessed and compared.Results:On both 1.5 T and 3.0 T MRI,the Go-Gr alloy crown exhibited significantly wider arti-facts than the others (ANAVO analysis,P<0.01).There were no significant differences among Ni-Gr,low-Ti alloy and Pure-Ti on 1.5 T MRI(P>0.05).On 3.0 T MRI the artifacts produced by Ni-Gr was larger than that by low-Ti alloy or Pure-Ti(P<0.05,be-tween low-Ti alloy and pure-Ti,P>0.05).By any of the test sequence either on 1.5 T or on 3.0 T,the Co-Gr alloy produced arti-facts in the most slices of MRI imaging and Pure-Ti in the least.Conclusion:Go-Gr alloy may produce larger artifacts than Ni-Gr, low-Ti alloy and Pure-Ti on MRI.