The authors used suspension cells of Populus euphratica to isolate protoplast in the present study. Protoplasts were successfully obtained after 4 hours incubation in enzyme solution containing 1 0% cellulase “o...The authors used suspension cells of Populus euphratica to isolate protoplast in the present study. Protoplasts were successfully obtained after 4 hours incubation in enzyme solution containing 1 0% cellulase “onozuka” R\|10, 0\^01% pectolyase Y\|23,0\^15% macerozyme R\|10 and 0\^1% hemicellulase at 25℃. Outward and inward single channels in plasma membrane were observed using cell\|attached recording of patch\|clamp technique. In this study, single channel records showed that more than one species of channel were obtained. These attempts in protoplast isolation and ion channel recording offers the opportunity to characterize cellular mechanisms of salt tolerance in tree species.展开更多
The patch clamp recording technique in vivois a blind patch clamp recording methods to record the current of the spinal or cereral neurons of anaes：hesia （ or awake） animals. This technique can be used to study the...The patch clamp recording technique in vivois a blind patch clamp recording methods to record the current of the spinal or cereral neurons of anaes：hesia （ or awake） animals. This technique can be used to study the synaptic function and plasticity in central nervous system in vivoin order to understand the physiological properties of the ion channels from an integrated point of view. The advantage of this technique have already presented itself in the study of the synaptic transmission and nervous network. Nowadays, in vivo patch whole-cell recording technique in combination with other techniques is becoming a common method in the research fields.展开更多
Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to de...Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.展开更多
This paper presents an automatic techruque of suitable reference potential selection for quantitative EEG interpretation.The 16-channels EEG recording under mono-polar derivation is analyzed.There are two prejudgments...This paper presents an automatic techruque of suitable reference potential selection for quantitative EEG interpretation.The 16-channels EEG recording under mono-polar derivation is analyzed.There are two prejudgments defined for checking the amplitude distribution and ear lobe activation.After prejudgments,the EEG is classified into several cases in cluding diffused case,non-diffused case,and artifact contami nation case.Due to the cases,an automatic reference selection method is applied in order to find out suitable reference potential.Finally,the referential derivation constructed according to the obtained reference potential,is evaluated for further EEG rhythm analysis.The presented technique can high light the EEG rhythm of interest,which is useful for quantitative EEG interpretation by both visual inspection and automatic evaluation.展开更多
文摘The authors used suspension cells of Populus euphratica to isolate protoplast in the present study. Protoplasts were successfully obtained after 4 hours incubation in enzyme solution containing 1 0% cellulase “onozuka” R\|10, 0\^01% pectolyase Y\|23,0\^15% macerozyme R\|10 and 0\^1% hemicellulase at 25℃. Outward and inward single channels in plasma membrane were observed using cell\|attached recording of patch\|clamp technique. In this study, single channel records showed that more than one species of channel were obtained. These attempts in protoplast isolation and ion channel recording offers the opportunity to characterize cellular mechanisms of salt tolerance in tree species.
文摘The patch clamp recording technique in vivois a blind patch clamp recording methods to record the current of the spinal or cereral neurons of anaes：hesia （ or awake） animals. This technique can be used to study the synaptic function and plasticity in central nervous system in vivoin order to understand the physiological properties of the ion channels from an integrated point of view. The advantage of this technique have already presented itself in the study of the synaptic transmission and nervous network. Nowadays, in vivo patch whole-cell recording technique in combination with other techniques is becoming a common method in the research fields.
基金supported by grants from the Fujian Provincial Natural Science Foundation of China (No. 2008J0075)the Fujian Provincial Science and Technology Project of China(No. 2010Y0011)
文摘Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.
基金Grant sponsor:National Natural Science Foundation of China,grant number:61074113grant sponsor:Shanghai Leading Academic Discipline Project,grant number:B504grant sponsor:Fundamental Research Funds for the Central Universities,grant number:WH0914028
文摘This paper presents an automatic techruque of suitable reference potential selection for quantitative EEG interpretation.The 16-channels EEG recording under mono-polar derivation is analyzed.There are two prejudgments defined for checking the amplitude distribution and ear lobe activation.After prejudgments,the EEG is classified into several cases in cluding diffused case,non-diffused case,and artifact contami nation case.Due to the cases,an automatic reference selection method is applied in order to find out suitable reference potential.Finally,the referential derivation constructed according to the obtained reference potential,is evaluated for further EEG rhythm analysis.The presented technique can high light the EEG rhythm of interest,which is useful for quantitative EEG interpretation by both visual inspection and automatic evaluation.
