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Objective:To prepare a phase-change lipid nanoparticle modified by tumor homing membrane-penetrating peptide (tLyP-1) and carrying paclitaxel (PTX) engineered by metal polyphenol network (TA-Fe 3+ ), and evaluate the therapeutic effects of tumor targeting, ultrasound/photoacoustic imaging and photothermal combined chemotherapy in vitro. Methods:Phase-change lipid nanoparticles (t-P@TFP) with TA-Fe 3+ engineered PTX mediated by tLyP-1 were prepared by solvent replacement method, thin film hydration method and double emulsification method. Its detection and characterization, in vitro targeting ability, photothermal conversion ability, in vitro photoacoustic and ultrasonic imaging ability, CCK-8 method, cell live and death double staining method and flow cytometry method were used to detect the safety of nanoparticles and the killing effects of different nanoparticles on 4T1 cells. Results:t-P@TFP nanoparticles were successfully prepared. Transmission electron microscopy showed that the nanoparticles were spherical with uniform shape and size, with a particle size of (209.8±1.56)nm and a potential of (-25.9±1.36)mV. Laser confocal scanning microscopy showed that t-P@TFP nanoparticles could gather around 4T1 cells in a targeted manner. It had an efficient photothermal conversion effect, and nanoparticles could quickly become microbubbles after being irradiated by near-infrared laser, which enhanced the in vitro ultrasonic imaging effect; The photoacoustic signal of nanoparticles increased with the increase of concentration. CCK-8 method, double staining of living and dead cells and flow cytometry showed that t-P@TFP combined photothermal chemotherapy had the best anti-tumor effect. Conclusions:t-P@TFP nanoparticles are successfully prepared. The nanoparticles have good targeting ability for photoacoustic and ultrasonic imaging and have good photothermal effect, killing breast cancer cells, which is expected to realize the integration of diagnosis and treatment.
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Objective:To explore the application effect of flipped classroom teaching method in musculoskeletal ultrasound teaching for standardized residency training of ultrasound department.Methods:In the study, 30 residents in ultrasound department of The Second Affiliated Hospital of Chongqing Medical University were collected and divided into control group ( n=15) and experimental group ( n=15). The control group was taught by traditional teaching method and the flipped teaching method was adopted in the experimental group. All residents were trained for 3 months. At the end of the training, theoretical test and operating skill test as well as the questionnaire survey were performed to evaluate the effects of these 2 teaching methods. SPSS 17.0 was used for t test and chi-square test. Results:The experimental group were superior to the control group in the aspects of the theoretical test scores, operating skill test scores, improving learning efficiency, building clinical thinking patterns, improving self-study ability, and there were significant differences. The satisfaction degree of teaching methods in the experiment group was higher than that in the control group, with significant differences ( P<0.001). Conclusion:Flipped classroom teaching method can improve the teaching outcomes and quality to ensure smooth completion of the teaching objectives.
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Objective To explore the relationship between iodine and fluoride content in drinking water and the incidence of adult thyroid nodules in Cangzhou,Hebei.Methods According to the previous reports on iodine and fluoride levels in drinking water in Cangzhou,from November 2016 to January 2017,Cangzhou was divided into high iodine,low iodine,normal iodine and fluorine,low iodine and high fluorine,high iodine and high fluorine areas,and according to the different contents of iodine and fluorine in drinking water,high iodine and high fluorine area was further divided into high iodine and high fluorine 1 (iodine:743.30 μg/L,fluorine:4.27 mg/L),2 (iodine:119.31μg/L,fluorine:4.67 mg/L) and 3 (iodine:105.30 μg/L,fluorine:1.64 mg/L) subareas.Subjects who lived for 20 or more years and aged 30 or older,without serious disease and not taken iodized salt were selected.Palpation was used to examine the size,texture,mass,tenderness and mobility of the thyroid gland.The boundary,internal echo,blood flow and quantity of nodules were observed and recorded by color Doppler.Results The prevalence difference of thyroid nodules [36.8％ (629/1 710),32.8％ (636/1 938),25.1％ (427/1 700)] in high iodine,low iodine and normal iodine and fluorine areas was statistically significant (x2 =55.597,P ＜ 0.05).The prevalences of thyroid nodules in both high iodine and low iodine areas were higher than that of normal iodine and fluorine area (P＜ 0.016 7).The prevalence difference of thyroid nodules [43.3％ (749/1 730),39.8％ (712/1 790),34.9％ (623/1 785)] in high iodine and high fluorine 1,2 and 3 subareas was statistically significant(x2 =26.220,P ＜ 0.05).Compared with low iodine area,the prevalence of thyroid nodules [41.2％ (735/1 785)] in low iodine and high fluorine area was increased (x2 =6.288,P ＜ 0.05).Conclusions Both high iodine and low iodine can induce thyroid nodules.In water source areas with high iodine content,both high iodine and high fluorine are the factors inducing thyroid nodules.The prevalence of thyroid nodules in low iodine and high fluorine area is significantly higher than that of low iodine area.
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ObjectiveTo evaluate the accuracy and reproducibility of three‐dimensional echocardiographic( 3DE) automated quantification technique for assessment of left heart chamber volumes and function in consecutive patients . Methods One hundred and fifty consecutive patients underwent 3DE were enrolled in the cross‐sectional study . According to image quality , the patients were divided into satisfactory group ( n ＝ 102 ) and unsatisfactory group ( n ＝ 33 ) . T he accuracy and reproducibility of automated 3DE for measuring left ventricular end‐diastolic volume ( LVEDV ) , left ventricular end‐systolicvolume ( LVESV ) ,left atrial volume ( LAV ) and left ventricular ejection fraction ( LVEF ) were evaluated by the traditional manual 3DE as the relative standard . Among those with satisfactory image quality ,the effects of cardiac cycle selection on automatic 3DE were analyzed . In addition ,according to LVEDV index and LAV index ,the patients were grouped as enlargement group and normal group ,and the significance of editing the endocardial boundaries for both groups were analyzed . Results ① One hundred and thirty‐five patients were successfully analyzed by the automated 3DE . T he inter‐technique comparisons showed good correlations ( r‐values :LVEDV 0 .90 ,LVESV 0 .87 ,LAV 0 .86 ,LVEF 0 .67 ;all P ＜ 0 .01 ) and small biases( LVEDV 11 .9 ml ,LVESV 6 .4 ml ,LAV 9 .0 ml ,LVEF －0 .4% ) for all measurements in all patients . ② T he various parameters in satisfactory group had better correlations and consistency than those in the unsatisfactory group( all P ＜0 .05) . ③Between the two different cardiac cycles ,the automated 3DE measurements showed good correlations( r‐values :EDV 0 .96 ,ESV 0 .96 ,LAV 0 .95 ,LVEF 0 .80 ;all P＜ 0 .01 ) . ④ After optimized boundary of the automated 3DE ,LVEDV ,LVESV increased and LVEF decreased in the left chamber enlargement group( all P ＜0 .05) . ⑤All automated measurements were more reproducible than conventional manual measurements in both intra‐/inter‐observer studies . Conclusions Since automated 3DE is accurate and reproducible for the assessment of left heart chamber volumes and function ,it can be widely used in clinical practice as a feasible and objective ultrasound technique .
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As an effective way,adjuvant chemotherapy is widely used in treatment of malignant tumors,whereas chemotherapy related cardiotoxicity has become an important factor influencing of patients' life quality and survival rate.Early,accurate prediction of cardiotoxicity is very important.Echocardiography is widely used to assess the cardiac function with advantages of convenience,economicly and noninvasion.New technologies of echocardiography can make up for the deficiency of conventional echocardiography and improve sensitivity and accuracy of cardiac function assessment,which making it possible to detect cardiotoxicity early and accurately.The progresses of echocardiography in evaluation of chemotherapy related cardiotoxicity were reviewed in this article.
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Acoustic cavitation triggered by low intensity ultrasound combined with microbubbles can lead to a series of biological effect on the organism.It provides a new,noninvasive,efficient method for the treatment of diseases,therefore having wide application prospect.The research progresses of ultrasound-stimulated microbubbles applied to tumor chemotherapy and arterial thrombolysis were reviewed in this article.
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Objective To evaluate the intra- and interatrial synchronization before and after pacemaker implantation in patients with sick sinus syndrome ( SSS) by tissue Doppler imaging ( TDI) . Methods Thirty-eight patients with SSS ( SSS group ) underwent pacemaker implantation . Echocardiography was performed before and after operation . Twenty-five volunteers were chosen as control group . Routine measurement of left and right atrial diameter by echocardiography . In apical four chamber view ,the sample volume of TDI was located at right atrial lateral wall at tricuspid annulus ,interatrial septum and left atrial lateral wall at mitral annulus . The interval time between the early diastolic wave ( E wave) and the late diastolic wave (A wave) (E-AR ,E-AI ,E-AL ) ,and the duration of A wave (AR ,AI ,AL ) were measured . At the same time ,the electromechanical coupling time was measured ,namely the initiation of the P wave of the synchronous electrocardiogram to the starting point of A wave ( P-A0R ,P-A0I ,P-A0L ) , and the starting point of the P wave to the peak point of the A wave ( P-AR ,P-AI ,P-AL ) . And the right atrial electromechanical delay time ,P-A0I and P-A0R value ( T0IR ) ,P-AI value and P-AR value ( TIR ) were recorded .Other parameters include left atrial electromechanical delay time:P-A0L and P-A0I value ( T0LI ) , and P-AL and P-AI value ( TLI ) ;interatrial electromechanical delay time:P-A0L and P-A0R value ( T0LR ) ,P-AL and P-AR ( TLR ) were recorded . Results Compared with the control group ,left atrium and right atrium in SSS group enlarged before operation , E-AR ,E-AI ,E-AL ,P-A0R ,P-A0I ,P-AR ,P-AL prolonged ,while T0LR and T0LI were shortened ( all P < 0 .05 ) . Postoperative changes in SSS group patients included shortened E-AR ,E-AI and E-AL ,and prolonged T0LI and T0LR ( all P <0 .05) . Compared with the control group ,the size of left atriums and right atriums in SSS group still increased postoperation ,and the P-A0I 、P-AR and P-AL remained longer (all P <0 .05) . The same as the control group ,the postoperative AR ,AI and AL in SSS group were decreased successively ( all P < 0 .05 ) . Conclusions In SSS patients , electromechanical asynchrony exists in different part of atrium and between left atrium and right atrium . Pacemaker therapy can improve atrial electromechanical synchronicity .
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Objective To evaluate the right ventricular global and regional strain and strain rate in patients with metabolic syndrome(MS) by two‐dimensional speckle tracking imaging(2D‐STI) ,and explore the correlation between different MS criteria and global strain and strain rate of right ventricle . Methods Forty‐four MS subjects ,35 pre‐MS subjects and 40 healthy subjects were enrolled . The basal ,middle and apical systolic longitudinal peak strain( Ss) and strain rate( SRs) ,early diastolic and late diastolic peak strain rate(SRe ,SRa) of right ventricular free wall were measured using 2D‐STI and global strain and strain rate ( GSs ,GSRs ) ,early diastolic and late diastolic peak strain rate ( GSRe ,GSRa ) of right ventricle were calculated . The correlation between different MS criteria and GS ,GSR of right ventricle were analyzed . Results Compared with control group ,Ss ,SRs ,SRe and SRa in basal and middle segments in MS group and Ss ,SRs in basal segment in Pre‐MS group decreased( all P 0 .05) . There were good correlation of waist circumference(WC) ,systolic blood pressure(SBP) ,fasting blood‐glucose with GSs( r =-0 .73 ,-0 .69 ,-0 .46 , P < 0 .01) and GSRs( r = -0 .63 ,-0 .78 ,-0 .48 , P < 0 .01) . The multiple regression analysis of MS criteria showed that waist circumference and systolic blood pressure were independently associated with GSs and GSRs of right ventricle(β= -0 .44 ,-0 .77 , P <0 .01) . Conclusions 2D‐STI could accurately assess right ventricular global and regional function in MS patients .Among all MS risk factors ,waist circumference and systolic blood pressure are the most responsible for right ventricular function .
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Objective To prepare a novel ultrasound contrast agent , targeted phase-shift lipid nanoparticles mediated by tumor homing and penetrating peptide tLyP-1 ,and to evaluate its characteristics . Methods The nanoparticles were prepared by filming-rehydration and acoustic-vibration methods .The morphology ,distribution ,particle size and zeta potential were detected . After heating and irradiating of low intensity focused ultrasound ( LIFU) ,the phase-shift characteristic and the enhancement effect in vitro were observed . The tumor homing and cell-penetrating properties of the nanoparticles were examined by confocal laser scanning microscopy and flow cytometry . The cytotoxicity of the nanoparticles was evaluated by CCK 8 assay . Results The size and distribution of nanoparticles were uniformed . The size and zeta potential of nanoparticles were ( 399 .50 ± 29 .98) nm and ( 3 .28 ± 1 .72) mV ,respectively . When the nanoparticles were heated to a temperature of 45 ℃ or after irradiated by LIFU ,nanoparticles generated phase-shift and enhanced ultrasound imaging in vitro ( P 0 .05 ) . Conclusions A novel ultrasound contrast agent , targeted phase-shift lipid nanoparticles mediated by tumor homing and penetrating peptide tLyP-1 ,is prepared successfully . It can target to MDA-MB-231 cell and penetrate into the cell in vitro ,and enhance ultrasound imaging in vitro after LIFU irradiation ,which expected to become a novel tumor targeted ultrasound contrast agent and achieve ultrasound molecular imaging at the level of tumor cell .
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Objective To quantify the right ventricular (RV) function in patients with left heart disease (LHD) related pulmonary hypertension (PH) by two-dimensional speckle tracking imaging (2D-STI),and explore its potential value in diagnosis of reactive PH.Methods Forty healthy volunteers and 65 patients with LHD related PH were enrolled.PH patients were further divided into two subgroups according to pulmonary vascular resistance(PVR):passive PH group and reactive PH group.A complete 2D-STI derived longitudinal strain of RV free wall was performed,and the basal,middle,apical longitudinal peak systolic strain (LS) and RV free wall global LS (RVLSbas,RVLSmid,RVLSapi and RVLSfw) were measured.Results Compared to control group,RVLSbas and RVLSfw in reactive PH group decreased significantly (all P ＜0.05).Compared to passive PH group,RVLSbas and RVLSfw in patients with reactive PH decreased significantly (all P ＜0.05).The differences of RVLSbas and RVLSfw between control group and passive PH group had no statistical significance (all P ＞0.05).No significant differences in etiology and left ventricular ejection fraction (LVEF) were observed between PH subgroups (all P ＞0.05).The area under the ROC curve of RVLSbas in predicting reactive PH was 0.93,the cut-off value was-21.86,and the sensitivity and specificity were 83 ％ and 89 ％,respectively.The area under the ROC curve of RVLSfw was 0.79,the cut-off value was-13.84,and the sensitivity and specificity were 59％ and 89％,respectively.Conclusions 2D-STI can realize quantitative assessment of RV function in patients with LHD related PH.RVLSbas and RVLSfw may have important clinical value in diagnosing patients with reactive PH,and differential diagnosis value between patients with passive PH and patients with reactive PH.
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Objective To investigate the application value of real clinical case centered situation simulation examination model in clinical medicine. Methods Two classes were randomly selected from 2008 grade clinical medicine majors, respectively as test group(n=158) and control group(n=156). Final examination of test group includes usual performance, case-oriented situation simulation examination (COSSE) and final written examination. Traditional methods were used in control group. The same paper was used in final written examination of the two groups. Scores of written examination and question-naires were used to evaluate the COSSE model. Data were processed using SPSS 16.0 statistical software;t and chi-square tests were used to analyze the data;P<0.05 signifies that the difference is statistically sig-nificant. Results Scores of final examination in test group were higher than those in control group(P<0.001). Times of independent completion of history taking, physical examinations and medical record writing were more in test group than in control group(P=0.002,0.017,0.048). Conclusions Contents and methods of COSSE is conducive to improving student's professional comprehensive ability.
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Objective To prepare a kind of P-selectin antibody loaded-targeted ultrasound contrast agent,and to investigate its ability of targeting in vitro.Methods P-selectin antibody loaded-targeted ultrasound contrast agent was prepared via an avidin-biotin bridge.Its basic property was determined.Human umbilical vein endothelial cells (HUVECs) were stimulated to express P-selectin by applying different doses of recombinant human interleukin-4 (rhIL-4) and histamine.The expression level of P-selectin was detected by immunofluorescence technique,and explored rhIL-4 optimal stimulation dose.The experiment group was divided into 3 groups,including targeted ultrasound contrast agent,isotype control ultrasound contrast agent and blank ultrasound contrast agent.Targeting abilities of 3 groups were observed by adhering to treated HUVECs and untreated HUVECs,respectively.Results P-selectin antibody loaded targeted ultrasound contrast agent was prepared successfully.The average diameter was (2.24 ± 0.71)μm.The average Zeta potential was (-2.75 ± 0.84)mV.The concentration was (3.0 ± 0.3) × 109/ml.The rate of antibody binding was as high as 99.80％.RhIL-4 and histamine could stimulate HUVECs to express P-selectin,and optimal stimulation dose was obtained.Targeting experiment showed that targeted ultrasound contrast agent could preferably adhere to HUVECs stimulated by optimal dose of rhIL-4 and histamine.Compared with other groups,there were significant differences.Conclusions P-selectin antibody loaded targeted ultrasound contrast agent was prepared successfully via an avidin-biotin bridge.The targeted ultrasound contrast agent could effectively adhere to HUVECs stimulated by rhIL-4 and histamine.
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Objective To investigate whether pulsed ultrasound-mediated microbubbles destruction could effectively enhance the efficiency of liposome delivery plasmid to hepatoma cells.Methods The cultured HepG2 cells were divided into six groups.The first group was as contrast group and the second group was given proper dose of liposome and plasmid.Pulsed-ultrasound exposed liposome was the third group.Add plasmid and microbubbles to the fourth group and exposed to pulsed-ultrasound.Add plasmid and liposome to the fifth group and exposed to pulsed-ultrasound,too.Liposome with plasmid and microbubbles were applied to the sixth group and exposed to ultrasound.After 24 hours,the EGFP expression in the hepatoma cells was detected by fluorescence microscopy and MTT.Results Green fluorescence intensity and transfection efficiency of the fifth group were higher than that of other groups,and cell viability had no significant difference.Although they were high in the sixth group,cells were partly died.Conclusions The liposome delivered EGFP expression efficiency in hepatoma cells was increased with the administration of pulsed ultrasound-mediated microbubbles destruction.In certain condition,microbubbles can enhance the efficiency of plasmid.
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Objective To prepare the lipid ultrasound microbubbles carrying gene and transactivating transc"ptional activator(Tat)peptide and to study the efficiency of carrying gene and Tat as well as to study their ability as an ultrasound contrast agent.Methods The lipid ultrasound microbubbles were prepared using mechanical vibration method.The appearance,distribution,concentration,diameter and zeta potential were measured.The efficiencies of carrying gene and Tat were studyed by a confocal laser scanning microscopy and a fluorospectrophotometer.For the in vivo experiment,contrast-enhanced ultrasonography was performed on six rabbits to observe the duration and intensity of enhancement in the heart chambers and myocardium after the injection of the microbubbles.Results The diameter of the self-made lipid microbubbles carrying gene and Tat was(2.27±0.38)μm,the concentration was(3.07±0.42)×109/ml and zeta potential was(1.95±0.13)mV.The gene encapsulation efficiency for the lipid ultrasound microbubbles was 32%,and the Tat encapsulation efficiency was 35%.The in vivo experiment showed that the lipid ultrasound microbubbles could significantly enhance the echo intensity of myocardium.Conclusions The efficiency of carrying gene and Tat for the prepared lipid microbubbles is high,which can be used as a new vehicle carrying genes or drugs for therapy as well as an ultrasound contrast agent.