Objective To prepare the quantum dots(QDs) (CdTe-MPA)-loaded polymer(lactic-coglycolic acid,PLGA) microbubbles(MBQDs@PLGA) as dual-modality imaging agent for both fluorescent and ultrasonic imaging ability.Methods The MBQDs@PLGA were generated by the double emulsion technique,then filling in C3F8 after freeze-drying.Confocal laser scanning microscope(CLSM) and transmission electron microscope(TEM) were used to confirm the load of quantum dots in the MBs.Fluorospectro photometer spectra of the MBQDs@PLGA were analyzed to demonstrate the fluorescent imaging ability and determine the encapsulation efficiency by using the regression equation.Imaging experiments was applied to validate the fluorescent and ultrasonic imaging ability of the MBQDs@PLGA both by imaging of the model in vitro and by imaging of ovarian tumor blood vessels of tumor-bearing nude mouse in vivo.Results At excitation 272 nm the MBQDs@PLGA peak of the emission spectrum was 549 nm,and the encapsulation efficiency was 54％.The average diameter of MBQDs@PLGA was (1.7 ±0.2)μm,CLSM and TEM results confirmed the QDs-loaded in MBQDs-PLGA.The imaging results of MBQDs@PLGA showed a dual-modality imaging ability both fluorescent and ultrasonic imaging.Conclusions MBQDs@PLGA present fluorescence-ultrasound dual mode imaging performance by the QDs embedding in polymer microbubbles,and explore a new development train of thought of multi-mode imaging agent.

Objective To assess the clinical features and treatment of children with long QT syndrome (LQTS)and syncope.Methods Eleven cases of children with LQTS and syncope between January 2009 and July 2014 in Hunan Children′s Hospital were retrospectively analyzed for clinical features,treatment and long term follow -up.Results There were 11 cases of children with LQTS aged 4.0 -14.5(9.16 ±2.71)years,8 male and 3 female, with syncope more than once.The range of QTc was 460 -521(483.72 ±22.90)ms.For 3 cases of acquired LQTS,1 case was parathyroid hypothyroidism causing hypocalcemia,1 case was myocarditis complicated with third degree atrio-ventricular block,and 1 case showed atrial flutter receiving amiodarone post congenital cardiac surgery.All patients re-covered after the inducement removed and primary illness cured.For 8 cases of congenital LQTS,3 cases of LQTS un-derwent genetic test (1 case of KCNQ1 gene mutation,2 cases of KCNH2 gene mutation).One case died after frequent torsade de pointes (Tdp)and ventricular fibrillation during hospitalization,the remaining 7 patients were given oral pro-pranolol,potassium chloride sustained -release tablets after discharge.Follow -up time was 8 to 75 months,an average of (45.73 ±24.42)months.One case died suddenly at home after 25 months of follow -up.The remaining 6 cases of children with congenital LQTS could withstand general activities without syncope,in which 4 cases had normal QTc by electrocardiography(ECG),and the findings in 2 cases did not change compared with those previously.The QTc re-turned to normal in children with acquired LQTS in the follow -up review.Conclusions Children with congenital LQTS should receive early genetic screening and genotyping for rational use of drugs.For children with higher risk of sudden death,drug therapy combined with implantable cardioverter defibrillator should be considered.For acquired LQTS,it should be better to remove the inducement and treat primary disease actively.

Objective To investigate the effects of 5-aminolaevulinic acid-photodynamic therapy (ALA-PDT) on precancerous changes and carcinoma of the skin in situ. Methods Fifteen patients with actinic keratosis, 3 patients with erythroplasia of Queyrat and 8 patients with Bowen′s disease were given topical ALA followed by PDT. Results The clearance was achieved in 17 lesions of 15 patients with actinic keratosis, 2 patients with erythroplasia of Queyrat and 7 patients with Bowen′s disease by topical ALA-PDT. The recurrence rates were 13.33%, 0 and 14.28% for actinic keratosis, erythroplasia of Queyrat and Bowen′s disease, respectively. Conclusions Topical ALA-PDT is a simple, effective and new treatment with lower recurrent rates, no scar formation and excellent cosmetic results for precancerous changes and carcinoma in situ of the skin, especially for the large and multifocal lesions located on the face and external genitalia.

Objective To evaluate the plasma level of amino-terminal pro-brain natriuretic peptide(NT-proBNP) before and after treatment in children with dilated cardiomyopathy (DCM) and explore the relationship between NTproBNP and heart functional classes.To evaluate the significance of dynamic change in NT-proBNP level in children with dilated cardiomyopathy.Methods The study comprised 49 children with DCM from Aug.2011 to Sep.2013 in Hunan Children's Hospital.NT-proBNP levels were measured before and after treatment.All the patients were evaluated under the modified Ross Heart Association functional class and echocardiographic determination of left ventricular ejection fraction(LVEF) and fractional shortening(SF).The patients were divided into improvement group(38 cases) and the non-improvement group(11 cases) according to cardiac function after treatment.Results The plasma level of NTproBNP was positively correlated with Ross heart failure classification (r =0.756,P ＜ 0.01),and much better than LVEF and SF.To identify mild heart failure,the cut-off value of 329 ng/L was 93.8％ sensitive and 90.9％ specific.To identify moderate heart failure,the cut-off value of 2 833 ng/L was 95.6％ sensitive and 92.9％ specific.To identify severe heart failure,the cut-off value of 12 125 ng/L was 80.6％ sensitive and 84.8％ specific.There was significant difference in the improvement group before and after treatment(t =2.357,P ＜ 0.05).In non-improvement group there was no significant difference (t =0.132,P =0.778) before and after treatment.Conclusions There is significant correlation between the plasma level of NT-proBNP and heart failure severity.The dynamic changes in NT-proBNP levels before and after treatment can help us to determine the effect of treatment and prognosis.

Objective To prepare a kind of new lipid perfluorooctylbromide(PFOB) nanoparticles and to explore its potential application as an ultrasound contrast agent. Methods Lipid PFOB nanoparticles were prepared by microfluidization techniques. The morphology and distribution were observed with optical microscope and transmission electron microscope. Particle size and electric potential were determined with Malvern laser light scattering analyzer. Twelve normal Wistar rats were performed directly contrast imaging after injection of PFOB nanoparticles via caudal vein. Vital signs of the rats were monitored during the whole study. And eehogenie intensity of the liver was dynamically quantified through DFY ultrasound quantified analysis system. The mechanism of enhancement was studied by the frozen sections of rat's liver and spleen. Results The nanoparticles size and distribution were highly uniformed. The grey scale ultrasound imaging of the rat's liver and spleen were enhanced by PFOB nanoparticles. Ten seconds after PFOB nanoparticles injected,enhancement of liver began, the peak time was approximately 3 - 4 min, the duration of contrast enhancement was nearly up to 1 h, The enhancement of spleen was more significant and the duration was much longer. No abnormal changes of the rat's vital signs appeared during the study. Frozen sections suggested that PFOB nanoparticles accumulated in the liver and spleen was the potential mechanism of enhancement. Conclusions This novel and safe lipid PFOB nanoparticles could make prolonged enhancement of rat's liver and spleen,which has a good potency for ultrasound application.

Objective To evaluate and compare the predictive validity of the Braden Q and Braden pressure ulcer risk assessment scales in the acute pediatric patients, and explore the cutoff score of the scales. Methods We adopted the prospective cohort study design.The settings included three PICU of three different children's hospitals. Two nurses were appointed as the data collectors, and they were in charge of both the scoring and the skin assessment separately. Results We collected 145 samples. There were 9 patients who developed the pressure ulcers, and the incidence rate was 6.2%. The cutoff score of Braden Q and Braden scale was 17 and 14. The AUC of the ROC curve of the two scales was 0.481 and 0.398. Conclusions The Braden Q scale is more suitable for the pediatric patients. Further study is neededed to improve the scale.

Objective To evaluate the effect of ultrasound-guided interscalene brachial plexus block and nerve stimulator on operation around shoulder joints. Methods Sixty cases of patients scheduled for operation around shouler joints were randomly divided into group A and B , with 30 cases in each group. Patients in group A underwent interscalend brachial plexus block guided by nerve stimulator with 0.5% ropivacaine and those in group B interscalend brachial plexus block guided by ultrasound and nerve stimulator with 0.5% ropivacaine 30 mL. The number of puncture, the effect of anesthesia and complication of anesthesia in both groups were recorded. Results The number of puncture of group B was less than that of group A (P﹤0.05) while the effect of anesthesia and the duration of anesthesia of group B were similar to those of group A (P﹥0.05). There was no serious complications in two groups. Conclusion With definite anesthesia effect and less pain , ultrasound-guided interscalene brachial plexus block and nerve stimulator is simple and safe for operation around shouler joints.

Objectives To assess treatment outcomes and prognosis in infants with atrial flutter (AFL).Methods Thirty-four (34) cases of infants with AFL in Hunan Children's Hospital had been analyzed for clinical features, treatment outcomes and follow-up between March, 2009 and September, 2015. Based on ECG characteristics, the patients had been divided into simple and complex AFL groups. Based on age, they had been divided into neonates and non-neonates group. The aim of this study is to compare the clinical effects of drug treatment in different types of AFL.Resultsb With digitalis alone, the cardioversion rate was 37.5%,no signiflcant difference was observed between simple and complex AFL groups (45.8% vs 12.5%,P=0.206). Combining with other drugs, the cardioversion rate was 54.5%, which showed signiflcant difference between simple and complex AFL groups (76.9% vs 22.2%,P=0.036). The overall cardioversion rate was 70.6%, which showed signiflcant difference between simple and complex AFL groups(87.5% vs 30%,P=0.003). There was no signiflcant difference in pharmaceutical cardioversion rate between neonates and non-neonates group (85.7% vs 60.0%,P=0.216). Two cases with symptoms of heart failure used synchronized cardioversion. One patient restored to sinus rhythm, and another case was still recurrent of AFL after repeated electrical cardioversion, and eventually died of cardiogenic shock. After treatment, 9 patients were still with paroxysmal AFL and atrial tachycardia episodes, including 3 cases of simple type and 6 cases of complex type who were discharged with oral digoxin and propafenone treatment at home. 24 patients were followed up (3 months to 3 years and 4 months). 16 cases restored to sinus rhythm during hospitalization had no recurrence of AFL.Conclusions The overall treatment effects of AFL in infants were good. In simple type of AFL, most of patients did not need long-term antiarrhythmic drug therapy and the prognosis was good. The prognosis of treatment with conventional drug was poor in complex AFL group, with a higher rate of recurrence of AFL.

Objective To prepare lipid-coated ultrasound microbubbles containing 10-HCPT(HLM) and explore the antitumor effects on mice xenografed H22 solid tumor using the technique of ultrasound-mediated HLM destruction. Methods Sixty-four tumor-bearing mice were radomly divided into A and B groups. Each group was divided into four groups again and administered respectively by tail vein with HI.M, non-drug-loaded microbubbles,10-HCPT and saline once a day. Ultrasound irradiation was applied on the tumor sites immediately after injection. After 7 days of consecutive treatment, all mice in group A were sacrificed and the tumors were harvested to measure weights. The tumor inhibition rate was calculated by weights. The tumor microvessel density (MVD) was detected by immunohistochemical staining. The tumor growth curve was depicted according to volumes. The survival time of mice in group B was recorded. Results The tumor inhibition rate was the highest in HLM group while this group's MVD was the lowest. Survival time in HLM group and 10-HCPT group were obviously longer compared with the control group,while no statistic difference was observed between the two groups. There was no statistic difference between the group of non-drug-loaded microbubbles and the control group. Conclusions Ultrasound irradiation mediates HLM destruction so that the drug is released from the vihicles at the same time, which can significantly enhance the tumor inhibition effect of 10-HCPT on the H22 tumor. This technique is expected to be adopted as a novel tool for liver cancer chemotherapy.

Objective To optimize the formulation of a new kind of ultrasound contrast agents carrying the sensitizer of hematoporphyrin(HP)with[Poly(lactic-co-glycolic acid),PLGA]for material.Methods The technique of double emulsion was applied to produce HP loaded PLGA ultrasound microbubbles,which was optimized through orthogonal test using encapsulation efficiency for the detected index.Then morphology and distribution of HP-PLGA microbubbles were observed through light microscope and scaning electron microscope.The size,Zeta potential and the properties of releasing behavior and ultrasound imaging in vitro of Hp-PLGA contrast agents were detected.Results The optimization parameters were picked out as 10 mg/ml for concentration of HP,40 mg for PLGA,and 1/5 for volume ratio of water inside to dichloromethane.The optimized HP-PLGA contrast agents were spheric with the mean size of 602.3 nm,and Zeta potentiaI of-(17.1±1.6)mV.The drug loading and encapsulation efficiency of HP-PLGA were(2.15±0.15)%and(63.5±2.6)%,respectively.And the releasing behavior of HP-PLGA contrast agents in vitro was that after an obvious release of about 35.1%in former 24 h,there were 86.5%HP-PLGA released within 14 days.The ultrasound imaging of HP-PLGA could be enhanced obviously in vitro.Conclusions The self-made HP-PLGA ultrasound microbubble might be a useful tool for delivering sensitizer and thus provide a novel strategy for sonodynamic therapy on tumor.