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Objective To investigate the effects of ultrasound combined with microbubbles on intracellular Ca2+ homeostasis in carboplatin ( CBP )-treated A549 cell and its possible mechanisms of inhibiting A549 cell line activity . Methods According to whether SonoVue was used or not ,and the different dose of CBP ,the groups A-F were arranged as the ultrasound(US) group(group A) ,the ultrasound combined with microbubbles ( USMB) group( group B) ,the low dose CBP ( 100 μg/ml) + US group( group C) ,the low dose CBP+USMB group( group D) ,the high dose CBP ( 200 μg/ml)+ US group ( group E) and the high dose CBP+USMB group( group F) .A549 cells were bathed and washed by a calcium-free buffer , loaded with Ca2+ indicator fluo-4 AM . Real-time images were acquired using laser confocal microscopy .The fluorescence intensity of intracellular calcium ion concentration ([Ca2+ ]i) in individual living cell was observed and the calcium overload was analyzed . Results After ultrasound irradiation ,the normalized fluorescence intensity of [Ca2+ ]i increased rapidly ,then returned to a new homeostasis (selected cells in groups A ,B ,E ,F) or experienced a second calcium oscillation ( some cells in group C and D) . All the selected cells in group B and some cells in group C and D exhibited superimposed oscillations . The calcium overloading time in group D was longer than those of any other groups . Four cells in group A experienced delayed calcium oscillations . Compared with group A ,the selected cells in other groups exhibited a larger amplitude of calcium oscillation( all P < 0 .05) and the selected cells in group B and D exhibited calcium oscillation for a longer period of time( all P <0 .05) . Conclusions In the calcium-free buffer ,US ,USMB , CBP+ US ,CBP + USMB are direct stimuli of calcium overload in A 549 cells . SonoVue ,CBP ,CBP +SonoVue are all synergistic stimuli of calcium overload in A 549 cells irradiated by ultrasound .US ,USMB and CBP may synergistically induce calcium release from intracellular store sites in A 549 cells . Calcium overload is a possible mechanism of ultrasound combined with microbubbles in assisting CBP chemotherapy .
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To investigate the effects of ultrasound combined with microbubbles on intracellular Ca2+ homeostasis in carboplatin ( CBP )‐treated A549 cell and its possible mechanisms of inhibiting A549 cell line activity . Methods According to whether SonoVue was used or not ,and the different dose of CBP ,the groups A‐F were arranged as the ultrasound( US) group( group A ) ,the ultrasound combined with microbubbles ( USMB) group( group B) ,the low dose CBP ( 100 μg/ml) + US group( group C) ,the low dose CBP+USMB group( group D) ,the high dose CBP ( 200 μg/ml)+ US group ( group E) and the high dose CBP+USMB group( group F) .A549 cells were bathed and washed by a calcium‐free buffer , loaded with Ca2+ indicator fluo‐4 AM . Real‐time images were acquired using laser confocal microscopy . T he fluorescence intensity of intracellular calcium ion concentration ( [ Ca 2+ ] i ) in individual living cell was observed and the calcium overload was analyzed . Results After ultrasound irradiation ,the normalized fluorescence intensity of [ Ca2+ ] i increased rapidly ,then returned to a new homeostasis ( selected cells in groups A ,B ,E ,F ) or experienced a second calcium oscillation ( some cells in group C and D ) . All the selected cells in group B and some cells in group C and D exhibited superimposed oscillations . T he calcium overloading time in group D was longer than those of any other groups . Four cells in group A experienced delayed calcium oscillations . Compared with group A ,the selected cells in other groups exhibited a larger amplitude of calcium oscillation ( all P ＜ 0 .05 ) and the selected cells in group B and D exhibited calcium oscillation for a longer period of time( all P ＜0 .05) . Conclusions In the calcium‐free buffer ,US ,USMB , CBP+ US ,CBP + USMB are direct stimuli of calcium overload in A 549 cells . SonoVue ,CBP ,CBP +SonoVue are all synergistic stimuli of calcium overload in A 549 cells irradiated by ultrasound .US ,USMB and CBP may synergistically induce calcium release from intracellular store sites in A 549 cells . Calcium overload is a possible mechanism of ultrasound combined with microbubbles in assisting CBP chemotherapy .
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Objective To investigate the impact of ultrasound-targeted microbubble destruction ( UTMD) combined with carboplatin sustained release microspheres on the temperature of the tumor microenvironment and the concentration of the drug release in target tumor . Methods Twenty tumor bearing rabbits were randomly assigned into 4 groups : the control group without any treatment ; the carboplatin-loaded PLGA microspheres (CPMs) group ,only intratumoral injection of carboplatin sustained-release microspheres ;the S2000 group ,diagnostic ultrasound irradiation using S2000 equipment on local chemotherapy tumor tissue combined with lipid microbubbles ;the AP-170 group ,the same treatment as the S2000 group except the application of AP-170 instead of S2000 . Far-infrared thermography was performed to measure the tumor temperature . The experimental equipment of extracorporeal circulation was set up . The experimental conditions were assigned into 4 groups :37℃ CPMs group ,37℃ S2000 group ,37℃ AP-170 group ,40℃ AP-170 group . After irradiation experiment ,the carboplatin absorbance was measured at 229 nm wavelength . The absorbance difference of each group was compared with the 37℃ CPMs group ,and each group was tested 10 times . Results The intratumorous temperature in AP-170 group increased to (40 .24 ± 0 .72) ℃ ,which was significantly different from all the other groups ( P ＜ 0 .01).The in vitro drug release experiment showed that the absorbance in the 40 ℃ AP-170 group was 0 .1537 ± 0 .0094 ,which was significantly different from other groups ( P ＜ 0 .01).Higher temperature promoted the release of chemotherapeutic drugs from carboplatin sustained-release microspheres , thus enhanced the chemotherapeutic effect .This might be the mechanism that UTMD affects the microenvironment in this experiment .Conclusions UTMD increases the permeability of tumor cells .The increase of temperature promotes more drugs into the microenvironment of tumor cells .Thus ,the local chemotherapeutic effect is enhanced in the tumor .
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As the real-time and dynamic ultrasound images play an important role in the distance education of ultrasound medicine, the learning system is more dependent on the technology of modern net-work information. By using the DGX protocol, we have constructed an ultrasonic distance education system composed of 5 main operating terminals, which has ensured the reliable and adaptive window transmission, and has realized the optimization of the coding and decoding technology. At the same time, we have used the system to carry out ultrasonic distance education to medical students, the staff of our ultrasound department and the ultrasound doctors in other hospitals, and have achieved good results in practical application.
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Objective To investigate the feasibility of transfecting gene into HepG2 by therapeutic ultrasound combined with microbubble,and to explore the optimal ultrasonic parameters for high transfection efficiency.Methods HepG2 cells were cross-interval planted in 24-well plates.EGFP plasmid DNA and microbubbles were added to the cultured HepG2 and three parameters of the therapeutic ultrasound were optimized.Firstly,set ultrasonic intensity gradient (group A,from A1 to A5),which were 0.4 W/cm,0.8 W/cm2,1.2 W/cm2,1.6 W/cm2 and 2.0 W/cm2 respectively.Secondly,set the duty cycle gradient group (group B,from B1 to B3),which were 10％,20％ and 50％ respectively.Lastly,set the exposure time group(group C,from C1 to C3),which were 30 s,90 s and 180 s.After 24 hours,the expression of GFP was observed by fluorescence microscopy,the transfection rates was detected by flow cytometry,the cell death were assessed by trypan blue exclusion.Results The plasmid transfection efficiency was varied under different ultrasonic parameters.Within a certain range,the increasing of parameters can improve the transfection efficiency,but when the parameters were too large (eg.the intensity＞1.6 W/cm2 or 50％ duty cycle),the actual transfection efficiency decreased due to the increased cell death.When the ultrasonic intensity was 1.2 W/cm2,the transfection efficiency and mortality were better than the other subgroups of group A.When the duty cycle was 20％,the transfection efficiency and mortality rate were better than the other subgroups of group B.Continue to increase the exposure time over 90 s was not statistically significant (P ＞0.05) for transfection efficiency and cell mortality.Conclusions The ultrasound-targeted microbubble destruction is an efficient method for gene delivery in vitro.The transfection efficiency vary greatly under different parameters,so optimization parameters is conducive to the promotion of gene transfection.
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Objective To investigate the value of ultrasound guided autobiopsy technology in interventional diagnosis of pulmo-nary peripheral disease .Methods 117 cases of pulmonary peripheral disease proved by X-ray or CT ,confirmed by ultrasound ,but could not be identified the nature by the examination above ,were biopsied under the guidance of ultrasound .Results All the 117 ca-ses were biopsed successfully .115 cases of them had definite pathological results ,the pathological positivity rate was 98 .3% ,in which contained 20 cases of chronic inflammation ,14 cases of tuberculosis ,30 cases of squamous cell carcinoma ,45 cases of adeno-carcinoma ,6 cases small cell undifferentiated carcinoma .No complication ,such as pneumatothorax ,hemoptysis ,bleeding occurred during the operation .Conclusion The ultrasound guided autobiopsy technology in interventional diagnosis of pulmonary peripheral disease is a safe and effective technique ,the tissues obtained from ultrasound guided autobiopsy were adequate to pathological slide which can provide the basis of the clinical diagnosis .
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Objective To compare bolus infusion and replenishment using real low mechanical index contrast enhanced ultrasound in assessing the change of renal cortical perfusion.Methods Using dopamine (i.v.) at the dose of 0.5,2.0,5.0μg · kg- 1 · min- 1 to change renal blood perfusion of 20 rabbits,then during bolus or contant injection of SonoVue,at coded pulse inversion mode,real-time contrast ultrasound was performed,the latter method needed destroying microbubble at a high MI when amplitude reach a steady state,then recording the replenishment,peak intensity(A) and time to peak (PPT) were obtained through raw time-intensity curve,and slope rate of TIC(k) was acquired by curve fitting,standard effective renal plasma flow(ERPF) was measured through 4-aminohippuric acid clearancerate method,meanwhile correlations between ERPF and parameters were analyzed,as well as the paired samples t test for each parameter before and after dopamine administration.Results The ascending branchs of raw TIC of bolus infusion increased sharply and were approximately straight,then descended gradually,while that of replenishment looked like two straightlines with different slopes,then stayed horizontal Both the value of A of two methods were positively correlated with ERPF ( r b =0.85,r re =0.66),and were different at the same ERPF,meanwhile the value of TTP were negatively correlated with ERPF( r b =-0.92,r re =- 0.76),and there were no statistically difference between the two methods.k from Gamma fitting was far from correct,while k from exponential fitting was apparently correlated with ERPF ( r re =0.77 ).Conclusions Both bolus injection and constant injection-replenishment method can assess renal cortical blood perfusion,TIC parameters A and TTP represent regional blood volume fraction and microbubble velocity respectively.Bolus-infusion with real low mechanical index is more precise and available.Comparing with k,TTP is more appropriate to reflect perfusion velocity.
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Objective To investigate the effects of transplantated tumor capillary permeability under microbubble enhanced diagnostic ultrasound exposure.Methods Fourty eight rats were randomly divided into four groups after Walker 256 carcinomas were subcutaneousely implanted,named the control group (A),microbubbles group (B),ultrasound group (C),microbubbles and ultrasound group (D).Using Evans blue(EB) as the indicator for tumor capillary permeability,the microbubbles were injected through the vein with diagnostic ultrasound frequency as 1.75 MHz,mechanical index as 1.4.The spillover of EB was estimated under confocal laser microscope,meanwhile the contents of EB in the tumor tissues were calculated according to the standard curve and spectrophotometry.Results EB spillover was observed around the capillaries in the group D,while EB spillover was only observable on capillary in group A,B and C.The EB content was also significantly higher than those in group A,B and C.Conclusions Exposure to both diagnostic ultrasound and microbubbles results in increased capillary permeability of rat tumor tissues,which might become a potential therapeutic method on clinical chemotherapy.
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100 U/ml and treated for 48 h,the inhibitory ratio of the HepG2 cells was raised to (39.08?2.32)%,which were not further elevated with the increase of dose or elapse of treatment time. HepG2 cells apoptosis was induced by thrombin.in a dose-and time-dependent manner when the dose was between 25 to 100 U/ml. However,there was no significant difference in the apoptosis of different groups when the dose was higher than 100 U/ml and the time exceed 48 h. Conclusion Higher doses of thrombin can inhibit the proliferation of HepG2 cells,and lead to cell apoptosis. The both effects are increased in a dose-and time-dependent manner when the dose is
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Different doses of ~(90)Y glass microspheres weres injected into the livers of rabbits under ultrasound guidance to observe the distribution of isotope in the body and the histologic alteration in the liver. The result showed that the isotope microspheres were only limited at the injected areas. The areas o.f bremsstrahlung ranged 4.1～12.55cm~2(mean 8.45cm~2). Whole body scanning revealed that the isotope was not observed outside the liver and no injury of non-target organ was present. When the dose was 35 mci, complete necrosis appeared in the hepatic cells within the bremsstrahlung areas. The study indicales that intrahepatic injection of ~(90)Y glass microspheres is accurmuate in locallization, produces high local iradiation energy and may become a non-surgical way for treating carcinoma of liver.