AIM To study the effect of CGRP on L-type calcium channel current in guinea pig ventricular myocytes under normal and imitating ischemia and hypoxia conditions. METHOD The whole-cell patch clamp recording technique was used. RESULTS When the ventricular cell was held at -40 mV and depolarized to 0 mV, 1?10 -9 、1?10 -8 and 1?10 -7 mol?L -1 CGRP increased I Ca-L from(1 26?0 18)nA ( n =8) to (1 87?0 25)nA ( P

AIM:To study the blocking effects of extracellular Cd2+ on the inward rectifier potassium channel (IRK1) expressed in the Xenopus oocytes. METHODS：Two-microelectrode voltage clamp (TEV) method was used. RESULTS：Cd2+ can concentration-, time- and voltage dependently block IRK1 instantaneous currents ( 1.5 ms after voltage applied ) when external Cd2+ concentration is 0, 0.1, 0.15, 0.3, 0.9, 2.7 or 5.4 mmol/L with K+ concentration fixed to 90 mmol/L. Cd2+ almost has no effect on the gating property and outward currents of IRK1. Cd2+ can concentration-dependently increase the normalized conductance of IRK1. IRK1 can not permeate Cd2+ because reverse potential did not change. Three exponential fitting analyze indicates that time constant is not changed with the change in Cd2+ concentration. This shows that the inhibitory effects of Cd2+ may be caused by surface potential or the blocking site of Cd2+ is at the surface of the channel. Because external Cd2+ can not inhibit IRK1 macroscopic currents more powerfully when external Cd2+ concentration is lower. These mean that external Cd2+ does not work through surface potential mechanism.CONCLUSION:Cd2+ is considered as one of the fast open channel blockers of IRK1 and its blocking site is at the surface of the channel.

AIM: To study the blocking effects of extracellular Cd 2+ on the inward rectifier potassium channel (IRK1) expressed in the Xenopus oocytes METHODS:Two-microelectrode voltage clamp (TEV) method was used RESULTS:Cd 2+ can concentration-, time- and voltage dependently block IRK1 instantaneous currents ( 1 5 ms after voltage applied ) when external Cd 2+ concentration is 0, 0 1, 0 15, 0 3, 0 9, 2 7 or 5 4 mmol/L with K + concentration fixed to 90 mmol/L Cd 2+ almost has no effect on the gating property and outward currents of IRK1 Cd 2+ can concentration-dependently increase the normalized conductance of IRK1 IRK1 can not permeate Cd 2+ because reverse potential did not change Three exponential fitting analyze indicates that time constant is not changed with the change in Cd 2+ concentration This shows that the inhibitory effects of Cd 2+ may be caused by surface potential or the blocking site of Cd 2+ is at the surface of the channel Because external Cd 2+ can not inhibit IRK1 macroscopic currents more powerfully when external Cd 2+ concentration is lower These mean that external Cd 2+ does not work through surface potential mechanism CONCLUSION: Cd 2+ is considered as one of the fast open channel blockers of IRK1 and its blocking site is at the surface of the channel

Objective The incidence rate of complication during central venous catheterization through internal jugular vein (IJV) and subclavian vein (SV) puncture. Methods Clinical controlled trials about IJV and SV puncture were collected and related literatures were screened according to the criteria of inclusion. The literatures underwent Meta analysis and subsequent analysis of sensitivity. Results A total of 18 literatures were included. Meta analysis indicated that statistical difference existed in the related infection rate [RR=1.74, 95%CI (1.32, 2.30)] and arterial puncture [RR=3.19, 95%CI (1.70, 5.99)], but not in the one-time-puncture success rate [RR=1.06, 95%CI (0.90, 1.24)] between IJV and SV puncture. Conclusions The rate of related infection and arterial puncture was higher by IJV than by SV puncture. But we could not confirm if any difference existed in the one-time-puncture success rate between the two methods. The results still needs evaluation by high-quality randomly controlled experiments.

Objective To investigate the clinical features,treatment,prognosis,and occurrence of neurogenic pulmonary edema(NPE) in children with severe hand-foot-mouth disease (HFMD) complicated with brain stem encephalitis and abnormal cranial magnetic resonance imaging (MRI).Methods 386 cases of severe HFMD were hospitalized in our Intensive Care Unit (ICU) from May to October 2010,of which 24 cases had abnormal cranial MRI.Their clinical symptoms,MRI features,treatment,and prognosis were analyzed.Results The clinical symptoms of severe HFMD with brainstem encephalitis included fever,startle,lethargy,vomiting,difficulty swallowing,drooling,and so on.The patients with abnormal cranial MRI were prone to have a neurogenic pulmonary edema (NPE) (5％ vs 6.5％,x2 =34.55,P ＜0.01).Conclusions The nervous system-affected parts of severe HFMD is the brain stem,thalamus,and spinal cord.Brain stem inflammation can be found early by the cranial MRI to be highly vigilant of NPE.During course of 1 ～ 5 day,special attention should be paid to the symptoms of the nervous system.The early detection,timely intervention,and prevention from NPE would result in the good prognosis.

Objective To investigate the effects of quiet respiratory intrathoracic pressure changes on ventricular dimensions and left ventricular systolic function,and to further verify our newly proposed hypothesis of the mechanism of respiratory effects on hemodynamics.Methods Twenty healthy volunteers aged 18 to 40 years average(24?7) years were included.The respiratory curve and electrocardiogram were simultaneously recorded.The interventricular septum movement,ventricular dimensions and ventricular systolic excursions were recorded by two-dimensional and M-mode echocardiography during quiet respiration.The respiratory variations of the above parameters were derived,and the parameters for assessing ventricular systolic function were calculated.Results With quiet respiration,the interventricular septum moved towards the left ventricle on inspiration,and then towards the right ventricle on expiration.The right ventricular diastolic dimension increased significantly on inspiration compared with those on expiration.The opposite changes occurred with left ventricular diastolic dimensions.The left ventricular posterior wall systolic excursion and the left ventricular stroke volume significantly increased during expiration compared with those during inspiration.No significant differences were found in left ventricular ejection fraction and fractional shortening between inspiration and expiration.Conclusions The respiratory intrathoracic pressure change is one of the factors influencing the reciprocal changes of the left and right ventricular parameters related to ventricular dimensions and systolic function.

Objective To evaluate the efficacy and safety of nasal continuous positive airway pres-sure (NCPAP) in treatment of severe pneumonia in children. Methods A series of 150 children with severe pneumonia were prospectively included from January 2016 to June 2017. The 150 children all still had short-ness of breath after 1 hours of nasal oxygen delivery,and then switched to NCPAP. We collected related clini-cal parameters (the basic vital signs,blood gas analysis index,shortness of breath,wheezing,groaning,nasal incitement,three depressions sign and NCPAP parameters) at three time points,including 0 h,1 h,4 h after using NCPAP. We compared the clinical parameters among the three time points before and after NCPAP with the purpose to assess the efficacy and safety of NCPAP. Results The proportion of shortness of breath (χ2=272. 218,P=0. 01),fast heart rate(χ2=31. 625,P=0. 01),wheezing(χ2=7. 624,P=0. 02),moaning (χ2=7. 203,P=0. 025),nasal flaring(χ2=74. 032,P＜0. 01),three depressions sign(χ2=117. 030,P＜0. 01) gradually decreased with statistically different among 0 h,1 h and 4 h after using NCPAP. PaO2/FiO2 (F=7. 32,P＜0. 01) gradually increased with statistically different among 0 h,1 h and 4 h after using NCPAP. Twenty-seven patients required intubations. PaO2and PaO2/FiO2in patiens received intubations were lower than those in patients only received NCPAP before treatment. Conclusion NCPAP is an effective and safe way for severe pneumonia children who remained abnormal breathing after conventional oxygen inhalation.

Objective To study the clinical data of patients treated with nasal continuous positive airway pressure (NCPAP) in PICU,and to explore the application time and range of NCPAP in critically ill children. Methods A prospective study was conducted to collect clinical data of 192 severe patients admitted to PICU from January 2016 to June 2017 who had shortness of breath after giving oxygen through nasal cath-eter for 1 hour and then switched to NCPAP. According to using NCPAP oxygen partial pressure,children were divided into three groups:group A[ shortness of breath ( PaO2≥70 mmHg,1 mmHg＝0. 133 kPa) ], group B[shortness of breath combined,reduced oxygen partial pressure(50mmHg