BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and...BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and the instability of intracellular calcium homeostasis.The present study aimed to determine the effect of CaMKII-ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia.METHODS:Forty New Zealand rabbits were randomized into four groups(10 per group):sham group,LVH group,KN-93 group(LVH+KN-93),and ryanodine group(LVH+ryanodine).Rabbits in the LVH,KN-93,and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta,while those in the sham group did not undergo the coarctation.After eight weeks,action potentials(APs) were recorded simultaneously in the endocardium and epicardium,and a transmural electrocardiogram(ECG) was also recorded in the rabbit left ventricular wedge model.Drugs were administered to the animals in the KN-93 and ryanodine groups,and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline(1 μmol/L) and high-frequency stimulation.RESULTS:The frequency(animals/group) of triggered APs was 0/10 in the sham group,10/10 in the LVH group,4/10 in the KN-93 group,and 1/10 in the ryanodine group.The frequencies of ventricular tachycardia were 0/10,9/10,3/10,and 1/10,respectively.The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10,7/10,2/10,and 1/10,respectively.The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group(P<0.05).CONCLUSIONS:KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH.The CaMKII-ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.展开更多
The opening of mitochondrial permeability transition pore（MPTP） plays a critical role in platelet activation. However,the potential trigger of the MPTP opening in platelet activation remains unknown. Inflammation is...The opening of mitochondrial permeability transition pore（MPTP） plays a critical role in platelet activation. However,the potential trigger of the MPTP opening in platelet activation remains unknown. Inflammation is the crucial trigger of platelet activation. In this study,we aimed to explore whether and how the important inflammatory cytokine IL-17 is associated with MPTP opening in platelets activation by using MPTP inhibitor cyclosporine-A（Cs A）. The mitochondrial membrane potential（Δψm） was detected to reflect MPTP opening levels. And the platelet aggregation,activation,and the primary signaling pathway were also tested. The results showed that the MPTP opening levels were increased and Δψm reduced in platelets administrated with IL-17. Moreover,the levels of aggregation,CD62 P,PAC-1,P53 and the phosphorylation of ERK2 were enhanced along with the MPTP opening in platelets pre-stimulated with IL-17. However,Cs A attenuated these effects triggered by IL-17. It was suggested that IL-17 could induce MPTP opening through ERK2 and P53 signaling pathway in platelet activation and aggregation.展开更多
A CMOS integrated signal processing circuit based on capacitance resonance principle whose structure is simple in capacitive sensors is designed. The waveform of output voltage is improved by choosing bootstrap refere...A CMOS integrated signal processing circuit based on capacitance resonance principle whose structure is simple in capacitive sensors is designed. The waveform of output voltage is improved by choosing bootstrap reference current mirror with initiate circuit, CMOS analogy switch and positive feedback of double-stage inverter in the circuit. Output voltage of this circuit is a symmetric square wave signal. The variation of sensitive capacitance, which is part of the capacitive sensors, can be denoted by the change of output voltage’s frequency. The whole circuit is designed with 1.5 μm P-well CMOS process and simulated by PSpice software. Output frequency varies from 261.05 kHz to 47.93 kHz if capacitance varies in the range of 1PF～15PF. And the variation of frequency can be easily detected using counter or SCU.展开更多
Terahertz time-domain spectroscopy(THz-TDS)system,as a new means of spectral analysis and detection,plays an increasingly pivotal role in basic scientific research.However,owing to the long scanning time of the tradit...Terahertz time-domain spectroscopy(THz-TDS)system,as a new means of spectral analysis and detection,plays an increasingly pivotal role in basic scientific research.However,owing to the long scanning time of the traditional THz-TDS system and the complex control of the asynchronous optical scanning(ASOPS)system,which requires frequent calibration,we combine traditional THz-TDS and ASOPS systems to form a composite system and propose an all-fiber trigger signal generation method based on the time overlapping interference signal generated by the collinear motion of two laser pulses.Finally,the time-domain and frequency-domain spectra are obtained by using two independent systems in the integrated systems.It is found that the full width at half maximum(FWHM)of the time-domain spectra and the spectral width of the frequency-domain spectra are almost the same,but the sampling speed of the ASOPS system is significantly faster than that of the traditional THz-TDS system,which conduces to the study of the transient characteristics of substances.展开更多
The modeling of Application Triggering Architecture (ATA) in the IP Multimedia Sub- system (IMS) is presented. The session setup delay and system throughput are employed as the measurement to investigate the performan...The modeling of Application Triggering Architecture (ATA) in the IP Multimedia Sub- system (IMS) is presented. The session setup delay and system throughput are employed as the measurement to investigate the performance of ATA and the Serving Call Session Control Function (S-CSCF). With theoretical analysis and simulation results, we find that, the number of the ASs (Application Servers), the use of the subsequent Filter Criteria (sFC) and the arrival rate have heavy impact on the session setup delay and the S-CSCF is the major bottleneck in IMS network. The results are useful in constructing IMS network. At last, we propose several possible solutions to reduce the session setup delay and decrease the load of the S-CSCF.展开更多
基金supported by a grant from Surface Project of Natural Science Foundation of Fujian Province(2008J0075)
文摘BACKGROUND:Calcium calmodulin-dependent kinase II(CaMKII) can be more active in patients with left ventricular hypertrophy(LVH),which in turn causes phosphorylation of ryanodine receptors,resulting in inactivation and the instability of intracellular calcium homeostasis.The present study aimed to determine the effect of CaMKII-ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia.METHODS:Forty New Zealand rabbits were randomized into four groups(10 per group):sham group,LVH group,KN-93 group(LVH+KN-93),and ryanodine group(LVH+ryanodine).Rabbits in the LVH,KN-93,and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta,while those in the sham group did not undergo the coarctation.After eight weeks,action potentials(APs) were recorded simultaneously in the endocardium and epicardium,and a transmural electrocardiogram(ECG) was also recorded in the rabbit left ventricular wedge model.Drugs were administered to the animals in the KN-93 and ryanodine groups,and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline(1 μmol/L) and high-frequency stimulation.RESULTS:The frequency(animals/group) of triggered APs was 0/10 in the sham group,10/10 in the LVH group,4/10 in the KN-93 group,and 1/10 in the ryanodine group.The frequencies of ventricular tachycardia were 0/10,9/10,3/10,and 1/10,respectively.The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10,7/10,2/10,and 1/10,respectively.The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group(P<0.05).CONCLUSIONS:KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH.The CaMKII-ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.
基金supported by the National Natural Science Foundation of China(Nos.81370425,81470502,and 81400283)
文摘The opening of mitochondrial permeability transition pore（MPTP） plays a critical role in platelet activation. However,the potential trigger of the MPTP opening in platelet activation remains unknown. Inflammation is the crucial trigger of platelet activation. In this study,we aimed to explore whether and how the important inflammatory cytokine IL-17 is associated with MPTP opening in platelets activation by using MPTP inhibitor cyclosporine-A（Cs A）. The mitochondrial membrane potential（Δψm） was detected to reflect MPTP opening levels. And the platelet aggregation,activation,and the primary signaling pathway were also tested. The results showed that the MPTP opening levels were increased and Δψm reduced in platelets administrated with IL-17. Moreover,the levels of aggregation,CD62 P,PAC-1,P53 and the phosphorylation of ERK2 were enhanced along with the MPTP opening in platelets pre-stimulated with IL-17. However,Cs A attenuated these effects triggered by IL-17. It was suggested that IL-17 could induce MPTP opening through ERK2 and P53 signaling pathway in platelet activation and aggregation.
文摘A CMOS integrated signal processing circuit based on capacitance resonance principle whose structure is simple in capacitive sensors is designed. The waveform of output voltage is improved by choosing bootstrap reference current mirror with initiate circuit, CMOS analogy switch and positive feedback of double-stage inverter in the circuit. Output voltage of this circuit is a symmetric square wave signal. The variation of sensitive capacitance, which is part of the capacitive sensors, can be denoted by the change of output voltage’s frequency. The whole circuit is designed with 1.5 μm P-well CMOS process and simulated by PSpice software. Output frequency varies from 261.05 kHz to 47.93 kHz if capacitance varies in the range of 1PF～15PF. And the variation of frequency can be easily detected using counter or SCU.
基金Project supported by the National Key Research and Development Program of China(Grant No.2021YFB3200100)the National Natural Science Foundation of China(Grant No.61575131)。
文摘Terahertz time-domain spectroscopy(THz-TDS)system,as a new means of spectral analysis and detection,plays an increasingly pivotal role in basic scientific research.However,owing to the long scanning time of the traditional THz-TDS system and the complex control of the asynchronous optical scanning(ASOPS)system,which requires frequent calibration,we combine traditional THz-TDS and ASOPS systems to form a composite system and propose an all-fiber trigger signal generation method based on the time overlapping interference signal generated by the collinear motion of two laser pulses.Finally,the time-domain and frequency-domain spectra are obtained by using two independent systems in the integrated systems.It is found that the full width at half maximum(FWHM)of the time-domain spectra and the spectral width of the frequency-domain spectra are almost the same,but the sampling speed of the ASOPS system is significantly faster than that of the traditional THz-TDS system,which conduces to the study of the transient characteristics of substances.
基金Supported by the National Science Fund for Distinguished Young Scholars (No.60525110)the National 973 Program (No.2007CB307100, 2007CB307103)+2 种基金the Program for New Century Excellent Talents in University (No. NCET-04-0111)the Development Fund Project for Electronic and Information Industry (Mobile Service and Application System Based on 3G)the National Spe-cific Project for Hi-Tech Industrialization and Information Equipments (Mobile Intelligent Network Supporting Value-added Data Services)
文摘The modeling of Application Triggering Architecture (ATA) in the IP Multimedia Sub- system (IMS) is presented. The session setup delay and system throughput are employed as the measurement to investigate the performance of ATA and the Serving Call Session Control Function (S-CSCF). With theoretical analysis and simulation results, we find that, the number of the ASs (Application Servers), the use of the subsequent Filter Criteria (sFC) and the arrival rate have heavy impact on the session setup delay and the S-CSCF is the major bottleneck in IMS network. The results are useful in constructing IMS network. At last, we propose several possible solutions to reduce the session setup delay and decrease the load of the S-CSCF.
