Effects of different doses of dexmedetomidine on cardiac conduction system / 临床麻醉学杂志

Objective To investigate the effect of dexmedetomidine on cardiac conduction system at different loading doses.Methods Eighty male patients with orthopedic surgery,aged 20-65 years,falling into ASA physical atatus Ⅰ or Ⅰ,were randomly divided into groups D1,D2,D3 and C with 20 in each.Groups D1,D2 and D3 were infused with dexmedetomidine 0.3,0.5 and 0.8μg/ kg using a micro-pump for 10 min,group C infused 0.9％ NaCl solution in the same manner.MAP,HR,SpO2 were recorded and ECG was traced before injection (T1),5 min (T2),10 min (T3) after injection and 10 min after the end of pumping (T4).P wave duration,P-R interval,QRS time,and QTc value were calculated.Results There was no significant difference in SpO2,P wave duration,P R interval and QRS time among the four groups.There was no significant difference in MAP,HR and QTc value in group C and group D1.Compared with that in group C,MAP was significantly decreased,HR was significantly slowed down and QTc value was significantly shortened in group D2 and D3 from T2 to T4 (P ＜ 0.05).Conclusion Dexmedetomidine does not affect the cardiac conduction system.0.5 μg/kg and 0.8μg/kg dexmedetomidine can effectively shorten the QT interval.To avoid severe bradycardia,patients with low heart rate should use no more than 0.5 μg/kg dexmedetomidine.

Lung protective effect of Shenfu injection on the legs' ischemia-reperfusion injury / 临床麻醉学杂志

Objective To discuss the lung protective effect of Shenfu injection on the legs' ischemia-reperfusion injury.Methods Sixty patients (6 males, 24 females, ASA grade Ⅰ or Ⅱ)with unilateral lower limb surgery, were randomly divided into Shenfu injection group (group SF, n=32) and control group (group C, n=28).All patients were treated by combined spinal epidural anesthesia, with the same dose of local anesthetic (0.75% bupivacaine 1.5 ml and the same pressure (300mm Hg) of tourniquet.Patients in group SF were given intravenous infusion of Shenfu injection with the dose of 1 ml/kg (added in normal saline 100 ml) 30 min before apply tourniquet and 1 ml/kg (added in nomal saline 50 ml) 5 min before tourniquet deflation.Patients in group C were injected with equal dose of compound sodium lactate at the same time.Recorded the hemodynamic changes before apply tourniquet (T0) and 5 min (T1), 15 min (T2) and 30 min (T3) after tourniquet deflation.Took venous blood to determine concentrations of plasma thromboxane B2 (TXB2) and malondialdehyde (MDA).Results Compared with T0, MAP in the two groups were significcantly lower at T1-T3 (P＜0.05).MAP in group SF at T2 and T3 were higher than those in group C (P＜0.05).There was no significant difference in HR between the two groups.TXB2 and MDA in group SF at T2 and T3 were significantly lower than those in group C (P＜0.05 or P＜0.01).Conclusion Shenfu injection with antioxidation has a protective effect on lower limb ischemia-reperfusion lung injury induced by tourniquet.

Efficacy analysis of ketamine on the patients with depression of modified electric convulsive therapy / 临床麻醉学杂志

Objective To observe the effects of ketamine on the patients with depression re-ceiving modified electric conulsive therapy (MECT).Methods Sixty patients with depression were randomly divided into ketamine group and propofol group (n =30 each group).Atropine 0.5-1.0 mg, propofol 1.0 mg/kg or ketamine 0.8 mg/kg i.v.were given before MECT,Scoline 0.7-1.0 mg/kg i. v.was given after the eyelash reflex disappeared.Hamilton Depression Rating Scale (HAMD)was completed after the 2 nd ,4 th and 6 th MECT,the time of convulsion,twitch index,energy percentage, respiratory recovery time and adverse reactions were recorded.Results The total score of HAMD was significantly decreased with the increasing times of MECT in both groups,compared with propo-fol group,ketamine group's HAMD total score decreased faster,especially after the 4th MECT,the score decreased significantly in ketamine group (P <0.05).The time of convulsion,twitch index,en-ergy percentage, respiratory recovery time, adverse reactions all had no statistical significance between the two groups.Conclusion Compered with propofol,ketamine,as an anesthetic of MECT, can effectively lower the score of HAMD.

The effect of dexmedetomidine on amino acid in cerebro-spinal fluid of patients undergoing intracranial tumor surgery / 临床麻醉学杂志

Objective To investigate the effect of dexmedetomidine on excitatory aminoacid (EAA)and inhibition of amino acid(IAA)in cerebro-spinal fluid(CSF)of patients undergoing in-tracranial tumor surgery,and to explore the cerebral protective mechanism of dexmedetomidine in neurosurgery.Methods Sixty patients aged 18-64 years old,ASA Ⅰ or Ⅱ,weighing 50-90 kg un-dergoing elective intracranial tumor surgery were randomly divided into dexmedetomidine group (group D)and control group(group C).Dexmedetomidine 1 μg/kg was infused before anesthesia in-duction for more than 10 minutes and pumped continously with 0.2-0.7 μg·kg-1·h-1 in group D, while in group C midazolam 0.03-0.05 mg/kg was injected followed by intermittent administration of 0.03-0.05 mg/kg.BIS value was maintained between 40-50.MAP and HR was recorded at the time points before induction(T0 ),dura mater incision(T1 ),tumor resection(T2 ),at the end of the surgery (T3 ).And we collected CSF at T0 ,T3 ,6 hours after the surgery(T4 ),12 hours after the surgery (T5 ),24 hours after the surgery(T6 ),then the concentrations of EAA and IAA were determined with high-performance liquid chromatography (HPLC)at T0 ,T3 ,T4 ,T5 and T6 .Results The MAP and HR in group D at T1-T3 were much lower than that in T0 and in group C(P <0.05).Compared with T0 ,the Glu and Asp in CSF significantly increased in group C at T3-T6 and were much higher than those in group D (P < 0.05 ),GABA was significantly decreased and much lower than group D(P <0.05).Compared with T0 ,the Glu and Asp in group D at T3-T5 were increased and GABA was decreased, but without statistic significance. At T6 , the values recovered to the level at T0 . Conclusion Dexmedetomidine can be used to maintain hemodynamic stability in intracranial tumor surgery,and may play a role in cerebral protection through inhibiting expression of Glu and Asp (EAA).

Investigation on developing a computerized imitating system of pediatric clinical patients / 中华医学教育探索杂志

The computerized imitating system constructed by the Second Affiliated Hospital of Guangzhou Medical University contains four blocks:administration of student infomation,administration of question bank,on-line tests and administration of score inquiry.It's designed to imitate typical pediatric cases,so that the medical students may put themselves into the practical clinical scenario and solve the challenges step by step in one-direction procedure.Teaching with computerized clinical scenario imitating patients can improve students' test resuhs and activate students' learning enthusiasm significantly.It not only helps to solve the contradiction between increasing number of medical students and clinical typical teaching case shortage but also improves the clinical thinking ability of the medical students.This system can also be used as a test bank for pediatric technical skills examination.

Construction of personalized full-length fully human mammalian display antibody library for children with systemic lupus erythematosus / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a personalized full-length fully human antibody mammalian display library for children with systemic lupus erythematosus (SLE).</p><p><b>METHODS</b>The total RNA was isolated from the PBMCs of SLE children. The heavy chain variable region and kappa light chain (VH and LCκ) of the antibody genes were amplified by RT-PCR and inserted into the pDGB-HC-TM vector separately to construct the heavy chain and light chain libraries. The library DNAs were transfected into 293T cells and the expression of full-length fully human antibody on the surface of 293T cells was analyzed by flow cytometry.</p><p><b>RESULTS</b>Using 0.8 µg total RNA as the template, the VH and LCκ were amplified and the full-length fully human antibody mammalian display library was constructed. The VH and LCκ gene libraries had a size of 9.4×10(4) and 8.4×10(4), respectively. Sequence analysis of 10 clones randomly selected from the VH and LCκ gene libraries each showed that 8 heavy chain clones and 7 light chain clones contained correct open reading frames, and flow cytometry demonstrated that all the 15 clones express full-length antibodies on 293T cell surfaces. 293T cells co-transfected with the VH and LCκ gene libraries expressed the full-length antibodies on the cell surface.</p><p><b>CONCLUSION</b>The personalized full-length fully human antibody library for SLE children constructed allows display of the full-length antibodies on mammalian cell surfaces, thus providing a valuable platform for analyzing the autoantibodies, their etiological role, and their clinical implications in SLE.</p>

Application of computerized imitating patients in training of pediatric respiratory system / 中华医学教育探索杂志

Objective A computerized clinical scenario imitating patients and clinical course variation for situation simulating teaching were established due to lack of typical patients,inadequacy of resourees in pediatric teaching probation and simplification in traditional teaching pattern.Methods Data of clinical typical patients were collected and recorded into video,and then these data were synthesized and put into computer,designing a computerized clinical setting imitating patients' set.216 uodergraduate students from grade 2008 were randomly divided into 2 groups.The patients in experimenial group were taught with computerized clinical scenario imitating patients,while traditional clinical probation in the hospital ward was carried out for those in the control group.Examination and questionnaire survey were performed at the end of the study.t test was used in statistical analysis.Results Comparison between the two groups using questionnaire survey showed that the learning motivation encouragement,active participation in teaching,guidance of clinical logical thinking and judgment,improvement of clinical thinking capacity,acceptance rate in classroom,preference rate were better in the experimental group than those in the control group (P ＜0.05).Student's performance in examination in the experimental group was higher than those in the control group ( P ＜ 0.05).Conclusion Teaching with computerized clinical scenario imitating patients is a teaching method closely related to clinical situation.It can significantly activate student's learning enthusiasm,improve clinical thinking and judgment capability,avoid risk of medical care and establish a new teaching setting for clinical pediatric teaching.

Predictive value for coronary heart disease by epicardial adipose tissue and carotid intima-media thickness / 中华超声影像学杂志

Objective To explore the predictive value for coronary heart disease by epicardial adipose tissue(EAT) thickness and carotid intima-media thickness(IMT) measured with high-frequency ultrasound.Methods According to the results of coronary angiography, the cases were divided into the normal control group (29 patients),coronary artery disease group with single-vessel lesion (43 patients),coronary artery disease group with multi-vessels lesion (28 patients), respectively. EAT and IMT were measured by high-frequency ultrasound. Results The EAT in the three groups were (4.8 ± 1.3) mm, (7.6 ± 1.8) mm,(10.1±2.6) mm respectively, and the IMT were (0.8±0.1)mm,(1.0±0.2)mm,(1.1 ± 0.2)mmrespectively. In either coronary artery disease group with single-vessel lesion or multi-vessels lesion, the EAT and IMT were significantly higher than those in the normal control group ( P＜ 0.01 ). And the difference between groups of single-vessel lesion and multi-vessels lesion was also statistically significant (P＜ 0.01). The areas under receive operating characteristic(ROC) curve to predict coronary heart disease by EAT and IMT was 0.947 and 0.917, respectively, there was no significant difference between the two areas. For patient with coronary artery stenosis＞50%, the sensitivity and specificity of EAT＞6 mm were 90.1% and 86.2% ,respectively,the sensitivity and specificity of IMT＞0.85 mm were 87.3% and 82.8%,respectively. Conclusions EAT and IMT measured by high-frequency ultrasound can precisely predictcoronary heart disease. EAT can be a new predictor to diagnose coronary heart disease.

Correlation between epicardial adipose tissue thickness and cardiovascular risk factors in patients with coronary artery disease / 中华超声影像学杂志

Objective To explore the correlation between epicardial adipose tissue(EAT) thickness and cardiovascular risk factors in patients with coronary artery disease.Methods According to the results of coronary angiography,84 cases of patients undergone coronary angiography were divided into the normal control group(28 patients),coronary artery disease group with single-vessel lesion (28 patients),coronary artery disease group with multi-vessels lesion(28 patients),respectively,then measured the EAT thickness and carotid intima-media thickness(IMT) by high-frequency ultrasound.A correlation analysis was carried out between the EAT and IMT and cardiovascular risk factors.Results In either coronary artery disease group with single-vessel lesion or multi-vessels lesion,the thicknesses of EAT and IMT were significantly higher than those in the normal control group(P ＜0.01),and the difference between group of single-vessel lesion and multi-vessels lesion was also statistically significant (P ＜0.01).A correlation analysis between the EAT and IMT and cardiovascular risk factors showed that there were significantly positive correlations between EAT and the IMT,age,weight,waist circumference,body mass index,low-density lipoprotein,Creactive protein (r = 0.124～0.790,P ＜0.05 or P ＜0.01),and the significantly negative correlation between EAT and high-density lipoprotein (r = - 0.203,P ＜ 0.05).Correlation between EAT and the IMT was 0.678,0.713,0.737 in the normal control group,group with single-vessel lesion,group with multivessels lesion,respectively.Conclusions There were favorable correlation between EAT and carotid IMT in cardiovascular risk factors.The more severity of coronary heart disease,the more high correlations of EAT and IMT.EAT can be a valuable index in evaluating coronary artery disease.

Evaluation of flow structure within left ventricle in patients with dilated cardiomyopathy by vector flow mapping / 中华超声影像学杂志

Objective To evaluate left ventricular function in the way of intracavitary flow dynamics by vector flow mapping (VFM) with echocardiography, and to discuss its clinical usefulness. Methods Twenty-six patients with dilated cardiomyopathy(DCM) and 44 healthy controls were involved. The velocity distribution imagings on the section plane of the flow in the left ventricle were obtained by VFM,and series parameters of velocity and distance were measured with DSA-RS1 software,including systolic parameters,such as velocity gradient from cardiac apex to the aortic valve(△Vs) ,distance from cardiac apex to the aortic valve(Ds), velocity according to half distance (Vs1/2), and diastolic parameters, such as velocity gradient from the mitral orifice to the apex(△Vd), distance from mitral orifice to cardiac apex(Dd),velocity according to half distance(Vd1/2). Results Compared with the values in the control group, parameters of systolic velocity(△Vs, Vs1/2 ) and parameters of diastolic velocity ( △Vd, Vd1/2 ) were significantly lower, parameter of systolic distance (Ds) and parameter of diastolic distance (Dd) were significantly longer( P ＜0.05). Ds,Dd were positive correlated with left ventricular(LV) end-diastolic volume(EDV), end-systolic volume (ESV) ,LV diameter ( r ＞0.4, P ＜0.01 ), and negtively correlated with LV ejection fraction(EF) ( r ＞0.3, P ＜0.01 ). Vs1/2, Vd1/2 were negtively correlated with EDV, ESV, LV diameter ( r ＞0.3, P ＜0.01 ),and positive correlated with EF( r ＞0.3, P ＜0.01 ). Conclusions The velocity of DCM group was lower than that of control group, VFM is a new noninvasive and clinically useful parameter for the evaluation of intracavitary flow dynamics.

Evaluation of vortex within left ventricle in patients with dilated cardiomyopathy by vector flow mapping / 中华超声影像学杂志

Objective To evaluate left ventricular function in the way of intracavitary vortex by vector flow mapping(VFM),and to demonstrate the formation and variation of the vortex. Methods Twenty-six patients with dilated cardiomyopathy(DCM) and 44 healthy controls were involved. The velocity distribution imagings on the section plane of the flow in the left ventricle were obtained by VFM, the location of the vortex and its variation in every phase of cardiac cycle were focused,and series parameters were measured,such as the diameter of the vortex (transverse diameter, vertical diameter), number of the vertex. Results relaxation(e) period. Vortices were observed mostly during diastolic period, nearby the anterior leaflet of mitral valve,middle upper 1/3 of left ventricle,and their shapes changed 2 - 3 times. The diameters of the vortex (transverse diameter,vertical diameter) , number of the vertices in one cardiac cycle during 7 phases mostly nearby the cardiac apex, middle lower 2/3 of left ventricle, and their shapes changed 4 - 5 times.Compared with control group,the diameters of the vortex (transverse diameter, vertical diameter) during 7 phases in DCM group were bigger,and number of the vertices were more ( P ＜0.01 ). The diameters of the vortex (transverse diameter, vertical diameter), number of the vertices within DCM group in one cardiac cycle during 7 phases were significantly different ( P ＜ 0.01 ). Conclusions VFM can demonstrate the variation of intracavitary vortex. Vortex in DCM group were significantly bigger than those of control group.

Evaluation of atrial septal defect using real-time three-dimensional echocardiography: comparison with surgical findings / 华中科技大学学报（医学）（英德文版）

The present study evaluated the application of three dimensional echocardigraphy (3DE) in the diagnosis of atrial septal defect (ASD) and the measurement of its size by 3DE and compared the size with surgical findings. Two-dimensional and real-time three dimensional echocardiography (RT3DE) was performed in 26 patients with atrial septal defect, and the echocardiographic data were compared with the surgical findings. Significant correlation was found between defect diameter by RT3DE and that measured during surgery (r=0.77, P<0.001). The defect area changed significantly during cardiac cycle. Percentage change in defect size during cardiac cycle ranged from 6%-70%. Our study showed that the size and morphology of atrial septal defect obtained with RT3DE correlate well with surgical findings. Therefore, RT3DE is a feasible and accurate non-invasive imaging tool for assessment of atrial septal size and dynamic changes.

Assessment of carotid atherosclerotic plaques using ultrasonographic elastography / 中华超声影像学杂志

Objective To evaluate the features of carotid atherosclerotic plaques on ultrasonographic elastography. Methods A total of 45 atherosclerotie plaques of the carotid artery in 33 patients were found with routine ultrasonography, all the 45 atherosclerotic plaques were divided into soft plaque, fibrous plaque, mixed plaque and calcified plaque. The elastograms of the plaques were oberseved and the strain contrast(stiffness ratio) of blood tissue in common carotid artery to plaques were calculated. Results Seventeen soft plaques, 15 mixed plaques and 13 calcified plaques were founded using routine ultrasonography, but 0 fibrous plaques were founded. The soft plaques were shown in green, the mixed plaques were showen as mosaic of green and blue and the calcified plaques were showen in blue by ultrasonographic elastography. The strain contrast in patients with calcified plaques and mixed plaques were significantly higher when compared with the soft plaques group(P 0. 001, P <0.05). The strain contrast in patients with calcified plaques was significantly higher than the mixed plaques group (P < 0.001). Conclusions Ultrasonographie elastography could be used in carotid arteries atherosclerotic plaques. Various of acoustic characteristics plaques has different elastography and strain contrast.

Evaluation of aortic valve function in patients with bicuspid aortic valve with echocardiography / 中华超声影像学杂志

Objective To evaluate the application of echocardiography in the diagnosis of bicuspid aortic valve and its pathophysiologic development and to demonstrate the degree of aortic valve dysfunction. Methods The echocardiographic characteristics and clinical data were analyzed retrospectively in 135 patients with bicuspid aortic valve to demonstrate the variation of aortic valve dysfunction in the progression of the course of the disease. Results Isolated aortic regurgitation was present in 68 (50%) patients, 19 (14%)patients had isolated aortic stenosis and 29 (22%)patients had combined aortic stenosis and regurgitation, 19 (14%) patients had neither stenosis nor regurgitation. Aortic regurgitation were all more commen within each age group, aortic regurgitation were also more commen within each age group in patients in their advanced course who went to surgical treatment. Conclusions Echocardiography is an effective method in the early diagnosis of aortic valve dysfunction.

Significance of bronchial challenge test in the therapy of childhood asthma / 中国基层医药

Objective To investigate the relation between symptoms/pulmonary function and airway inflammation of asthmatic children through follow-up investigation on the pulmonary function and airway inflammatory,in order to provide basis for regular asthmatic therapy.Methods The pulmonary function and histamine challenge test of 32 cases of 7～14 years old asthmatic children under regular inhalation corticosteroid(ICS) therapy were carried out and the relation between the symptoms/pulmonary function and airway reactivity were evaluated.Results During the remission period after regular ICS therapy,the mean of one second force expiratory volume(FEV_1),25% and 50% of vital capacity of force expiratory flow(FEF_ 25 and FEF_ 50 ) predicted improved significantly when comparing with those prior to the therapy(P

Problem-based learning (PBL)in clinical teaching of pediatric interns / 中华医学教育探索杂志

Objective To investigate problem-based learning(PBL)in clinical teaching of pediatric interns.Methods To compare and analyze the grades of pediatric interns’case writing before and after PBL.Results There was significant difference between the two groups and the grades of interns by PBL were notably higher.Conclusion PBL can improve the interns’ability of case writing,clinical thoughts,operation ability,and enhance their enthusiasm in learning.