0 05) 3 hours after myocardial infarction,and remarkably decreased (P

Objective To inquire into the effects of cardiac ? 1 -adrenergic receptor on myocardial remodeling and modulating calcium channel. Methods The models of myocardial remodeling after myocardial infarction in Wistar rats were used to study the expression changes of cardiac collagen subtype Ⅰ,Ⅲ,fibronectin (FN) with immunohistochemistry,and changes of T-type calcium channel,L-type calcium channel and ? 1 -adrenergic receptor mRNA expressions by reverse transcription and polymerase chain reaction(RT-PCR) and in situ hybridization. Cardiac total Ca 2+ was tested by atomic absorption/flame emission spectrophotometer. Results Cardiac collagenⅠ,collagen Ⅲ,FN protein expressions in betaloc group were remarkably decreased (P

Objective To inquire into the correlation of cardiac AT 1 receptor,? 1 receptor with PKC/MAPKs(protein kinase C/mitogen-activated protein kinase) signal transduction pathway during myocardial remodeling.Methods Twenty-four Wistar rats were randomly divided into four groups-sham group,infarcted group,losartan group and betaloc group.Except sham group,left anterior descending coronary artery was ligated for 21 days.In the other three groups,expression changes of cardiac collagen subtype Ⅰ,Ⅲ,fibronectin(FN),c-fos,ERK 1 (extracellular signal-regulated kinase,ERK)and PKC proteins were studied with immunohistochemistry and computer image analysis. c-fos mRNA expression was tested by reverse transcription and polymerase chain reaction(RT-PCR).Results Expressions of collagen Ⅰ,collagen Ⅲ , FN,c-fos,ERK 1 and PKC proteins were significantly enhanced(P

Adriamycin is an effective and broad-spectrum anthracycline antineoplastic agent.However,long-term therapy with adriamycin is associated with a high incidence of cumulative and irreversible cardiomyopathy. Mechanisms about adriamycin-induced cardiotoxieity are complicated, including oxidative stress,mitochondrionopathy,cardiac apoptosis,and so on.For the past few years,a series of measures aye used,which attenuate the cardiotoxicity and uninfluence the antitumor effects.The review focuses on the mechanism and prevention of adriamycin-induced cardiotoxicity in order to improve the long term survival rate of neoplastic patient.

Objective To inquire into T-type calcium channel effects on RyR and IP 3R of sarcoplasmic reticulum in atrial myocytes during atrial fibrillation.Methods Ten dogs underwent continuous rapid atrial pacing (500 beats/min) to create persistent atrial fibrillation.In five rapidly-paced dogs,mibefradil dihydrochloride was given beginning 2 days after pacemaker implantation,continuing until the twenty-fourth week.A group of size-matched dogs (n=5) without given mibefradil was used as a pure atrial fibrillation group.Another group of size-matched dogs (n=5) without pacemaker implantation was used as a control group.Canine atrial myocytes isolated by enzymatic dissociation were used to study T-type Ca 2+ channel blocker effects on expression and function changes of RyR and IP 3R in atrial myocytes by confocal microscopy.Results RyR/IP 3R ratio (0.2965?0.01812) was markedly lower than that of control group (2.7043?0.2293),but there was no difference compared with that of atrial fibrillation group (0.2472?0.1355).Ca 2+transient of atrial myocytes was nremarkably changed (1.3031?0.1056)(P

Objective To inquire into T-type calcium channel effects on atrial electrical remodelling and its mechanisms during atrial fibrillation.Methods Animal experiment was performed in Peking University Pepole's Hospital from Feb.2002 to Oct.2006.Fifteen adult cross-bred dogs were used in the experiment.Ten dogs underwent continuous rapid atrial pacing(500 beats/min)for twenty-four weeks to create persistent atrial fibrillation.In five rapidly-paced dogs,50mg pure powder/day of mibefradil dihydrochloride was given from the second day after pacemaker implantation and continued until the twenty-fourth week.A group of size-matched dogs(n=5)without being given mibefradil was used as a pure atrial fibrillation group.Another group of size-matched dogs(n=5)without pacemaker implantation was used as a control group.Atrial fibrillation duration was determined by electrophysiological study.Canine atrial myocytes were isolated by enzymatic dissociation and intracellular Ca2+ cytosolic transient was studied with confocal imaging.Results (1)The preoperation atrial effective refractory period was 280/90~110 ms.In the twenty-fourth week after rapid atrial pacing,atrial effective refractory period was obviously extended(2000/1400~1700 ms)in the T-type Ca2+ channel blocker group compared with the preoperation one.In the twenty-fourth week,the induced rate of persistent atrial fibrillation was 75% in atrial fibrillation group,whereas the persistent atrial fibrillation occurred in only one case(20%)in the T-type Ca2+ channel blocker group.(2)Intracellular Ca2+ concentration of atrial myocytes was unremarkably changed in control group after blocking L-type Ca2+ channel(1.17?0.09 OD ratio),whereas the intracellular Ca2+ concentration was obviously enhanced(2.35?1.05 OD ratio)(P

40 weeks old SHR did not differ from that in slices of age matched WKY. B max was increased in the same brain region of SHR when compared to WKY. That rats of 4 5 weeks were in prehypertensive stage;rats of 10 12 weeks and above were at the stage of establishing hypertensive stage. Conclusion: The difference between SHR and normotensive rats in 5 HT 1A receptor binding in various brain regions may be related to the development of hypertension. When blood pressure changes,binding capacity of 5 HT 1A receptor in CNS changes accordingly.

This design is a multi-point thermometry system based on single bus digital thermometer DS1820.The single bus system of multi-point measure temperature is developed with single chip computer 89C52 and circuit units for physiological signal measurement.Obtainment method of higher resolution temperature data is given.The method makes measure temperature resolution reach to 0.1?C.It is characterized by simplicity of structure,high precision and real time,and is easy to transmit by internet network.So the system has widely applications value on clinic.

Objective To develop an apparatus to measure pulse magnetic field. Methods Single chip computer and Hall-effect integrated circuit was utilized to measure the magnetic induction. The correlative hardware and software flow were given. The measuring range of apparatus was 0-50mT. Results The circuit was simple and the performance was safe and credible. The measuring precision was high. Conclusion It can be used for some kinds of magnetic induction measurement.

Objective To explore the immunophenotype features and folate receptor expression of blasts in patients with myelodysplastic syndromes(MDS).Methods Four-color flow cytometry using conventional and secondary gating strategies was used into analysis the immunophenotype features and folate receptor(FR) expression of blasts and CD+34 cells in bone marrow nucleated cells with MDS.The patients with acute myeloid leukemia-M2(AML-M2) were as positive control.Results with progression of MDS from RA/RAS,RAEB to RAEB-T,using conventional gating strategy,the proportion of CD+34 cells were gradually increased(P＜0.05).Moreover,the expression of HLA-DR,CDll7,CD13,CD33 were also gradually increased and the expression of CDl5 was gradually decreased(P＜0.05).Using secondary gating strategy,the expression of HLA-DR,CD117,CD13,CD33 on blasts were higher than those by conventional gating(P＜0.05).However,there was no significant difference(P＞0.05) in the expression of above mentioned antigens on CD+34 cells among different MDS subtypes.On the other hand,there were no expression of FR on blasts and cD+34 cells with different MDS subtypes.Conclusion With progression of MDS,the antigens of blasts surface change into more immature immunophenotype of medullary system.But these antigens abnormal expression only illustrates the increase of ascendant malignant clone quantity,it can not reflect the nature of the disease.Using flow cytometry technique can not detect whether or not FR expression on the blasts with MDS.