Objective To investigate the effects of ult rasonic cavitation on cell membrane cultured in vitro. Methods The rat pulmonary artery vascular smooth muscle cells were divided into three groups, control group, simple ultrasound radiation group and contrast plus ultrasound radiation group.The latter two groups were exposed to ultrasound(665 kHz, 0.5- W/cm 2) for 20 s but the last group with contrast agent. Immediately after the experiment or 24 hours after treatments, electron microscopic scanning was used to observe the membrane change. Results Compared with control group, the cell structure and cell surface had no apparent changes in the second group treated with ultrasound alone. In the third group, nearly 20% cells exhibited small holes with diameter mostly about 1-2 ?m in the cell surface and returned to normal appearance after 24 hours later. Conclusions Ultrasonic cavitation can cause small transient holes in cell surface and hence increase permeability of the cell membrane. It might be the main mechanism for gene delivery with ultrasound contrast agents.

Objective To combine the active poly lactic co-glycolic acid (PLGA) nanosperes with adriamycin in side (ADM-NP) on the surface of ultrasound micrbubbles in covalent bonding and to prepare a novel drug-loading ultrasound micrbubble,and observe the physicochemical property.To quantify drug encapsulation efficiency and drug-loading amounts and drug-release properties in vitro and the effect of tumor imaging.Methods ADM-NP were prepared with double emulsification method,The surface carboxyl of ADM-NP was activated with carbodiimide method.Amino ultrasound microbubbles (MB-NH2) were prepared with mechanical shaking.The carboxyl of ADM-NP and the MB-NH2 could take place condensation reaction under a certain condition.Light microscope was used to observe the shape and distribution of the novel micrbubble.High performance liquid chromatography (HPLC) was used to quantify drug encapsulation efficiency and drug loading amounts.This novel microbubbles were put in 2 dialysis bag to observe the releasing properties of ADM in vitro,and one of the bag was using low frequency ultrasound irradiation for 120 s.The effect of tumor imaging using this novel microbubble was observed.Results After 48 hours,a number of ADM-NP attacted to the MB-NH2 like a gar land.Determination of entrapment efficiency and drug loading of it by HPLC weare (86.11 ± 6.76)％ and (8.71 ± 0.46)％.The sustained release in vitro can last for more than 48 hours.More than 90％ of ADM encapsulated in the 2 groups was sustained released for 48 hours.And the release characteristics of the 2 groups in vitro was in accord with Higuchi equation,and no difference was observed in the 2 groups (P ＞0.05).The tumor showed typical enhancement pattems of quick wash-in and quick wash-out.Conclusions To combine the nanospheres to the surface of microbubbles with covalent bonding,it could prepare a novel efficient drug-loading microbubbles for a original technique of ultrasound-targeted microbubble destruction(UTMD).

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 explore the feasibility of virtual touch tissue quantification(VTQ) technique in noninvasive assessment of transjugular intrahepatic portosystemic stent shunt (TIPSS).Methods Twenty-four patients were enrolled in this study.Shear wave velocity(SWV) of the liver and spleen were obtained by VTQ technique on one day before TIPSS insertion and one week after TIPSS placement,and the portal vein pressure was measured while placing the TIPSS.The correlation between SWV of the liver and spleen and portal venous pressure were analysed.In addition,fourteen patients were followed up for one month after TIPSS placement.Results There was significant difference in portal vein pressure pre [(27.82 ± 4.07) mm Hg] and post [(16.26-± 3.10) mm Hg] TIPSS insertion.The SWV of the liver in patients pre and post TIPSS measured (2.43 ± 0.37)m/s and (2.40 ± 0.34)m/s,respectively.The SWV of the spleen in patients pre and post TIPSS were (3.49 ± 0.40)m/s and (3.08 ± 0.39)m/s,respectively,there was significant difference (P =0.000).However,SWV of the liver pre and post TIPSS placement was no significant difference(P =0.130).And as well as the patients which were followed up for one month after TIPSS placement.A significant,direct,linear correlation(r =0.602,P =0.000) was found between SWV of the spleen and portal vein pressure,but liver SWV was not correlated with the portal venous pressure.Conclusions SWV of the spleen measured by VTQ technique has a significant correlation with portal vein pressure.Hence,the spleen SWV based on VTQ technique can be used as a non-invasive method for quantitatively in monitoring the portal vein pressure as the function of the TIPSS.However,evidence to support a similar role for liver stiffness is lacking.

Objective To investigate how many probably benign lesions on ultrasound(US) fulfilled the published criteria and to evaluate how clinical and personal factors influenced the categorization of breast lesions.Methods A total of 487 lesions in 487 women with more than 12 months follow-up after the initial category 3 assessment on US were included.The initial US images were retrospectively reviewed according to previously published criteria,and evaluated several factors that could influence the characterization of breast lesions in clinical practice such as age,multiplicity,palpability,radiologist 's experience,and lesion size.Results Of 487 lesions,479 (98.36%) were benign and 8 (1.64%) were malignant.Of 487 lesions,203(41.68%) including 8 malignancies were reassessed as category 4.If strict criteria had been applied at initial US examination,the positive biopsy rate would have been only 3.94% (8/203) and 96.06% (195 of 203) biopsies would have been unnecessary.Lesions in women 40 years or older and multiple lesions were more frequently reassessed as category 4 (P = 0.008 and P = 0.006,respectively).The presence of palpability,lesion size,and the radiologist 's experience did not significantly influence the categorization of breast lesions on US.Of 487 probably benign lesions,41.68 % could be classified as category 4 lesions when strict criteria were applied in initial practice.Conclusions The multiplicity of the lesion and the patient 's age were found to have a significant influence on the classifcation of probably benign solid masses.

Objective To investigate the antitumor effect and its mechanism of microbubble contrast combined with Mitoxantrone exposed to low-frequency ultrasound on human breast cancer cell MCF-7. Methods MTT method was applied to examine the growth inhibition of MCF-7 treated with Mitoxantrone. MCF-7 cells were randomly divided into 4 groups:Mitoxantrone group (group D), ultrasound+Mitoxantrone group (group U+D), ultrasound+microbuble +Mitoxantrone group (group U+M+D) and control group (group C). The cytoactive of each group was examined with MTT. The intracellular drug content in each group was measured with high performance liquid chromatography. The morphology of MCF-7 cells apoptosis was observed with transmission electron microscopy (TEM). Results The IC_(50) of Mitoxantrone was 2.87 μg/ml. The differences of cytoactive among all groups were significant (P<0.05). The intracellular drug content of group U+M+D was higher than that of group U+D, and the latter was higher than that of group D. The morphological changes of apoptosis were observed with TEM. Conclusion Low-frequency ultrasound can promote intracellular drug content as to enhance the sensitivity of chemotherapy drugs on tumor cells, and this effect can be enhanced by microbubble contrast exposure to low-frequency ultrasound.

Purpose To explore the apoptosis mechanism of human ovarian cancer cells SKOV3 processed with ultrasound (US) combined with photodynamic therapy (PDT), with self-contained lactic acid/glycolic acid (PLGA) microbubbles (MBQDs/PLGA) containing quantum dots (QDs) as a photosensitizer. Materials and Methods MBQDs/PLGA was prepared with double emulsion method, and MTT was used to compare the cytotoxic activity difference between QDs and MBQDs/PLGA, to determine the proper treatment condition. SKOV3 cells were treated under selective conditions, cell damage manifestation was observed with HE staining, and double staining flow cytometry was used to detect cell apoptosis. Results When cells were treated with PDT with energy density of 180.0 J/cm2 and US with sound intensity of 0.5 W/cm2 (1.0 MHz, 10 s), cell deformation could be observed under a microscope in both US-PDT-MBQDs/PLGA group and PDT-MBQDs/PLGA group, and cell connections were absent between cells;transmission electron microscope showed dense chromatin gathered along the nuclear membrane, with the formation of apoptotic bodies also be displayed. Maximum apoptosis rate was (22.17±0.38)% Conclusion MBQDs/PLGA-mediated PDT contains proliferation inhibition effect for SKOV3 cells, which can be synergied with low-power ultrasonic irradiation due to sonoporation effect.

OBJECTIVE:To study the chemical constituents in antioxidant activity part of Semiaquilegia adoxoides. METH-ODS:The antioxidant activity part of S. adoxoides were isolated and purified by chromatography on silicagel and Sephadex LH-20 column,and compound structures were identified physicochemical properties and spectral data analysis. RESULTS:Nine com-pounds were isolated from the antioxidant activity part of S. adoxoides,namely magnoflorine (1),griffonilide (2),salidroside (3),ferulic acid(4),genistein(5),2,4-dihydroxybenzoic acid(6),chlorogenic acid(7),caffeic acid(8)and p-coumaric acid (9). CONCLUSIONS:The study confirms the active material basis in antioxidant activity part of S. adoxoides for the first time.

Objective To synthesize a photoacoustic contrast agent loaded with gold nanorod and liquid perflurocarbon which was used to observe its photoacoustic imaging in vitro,and then investigate the variation of the photoacoustic signal during and after the vaporization.Methods The PLGA nanoparticle (GNP)loaded with gold nanorod(GNR) and liquid perflurocarbon was synthesized via double emulsion technology.The experiments were divided into three groups:1)GNP group:PLGA nanoparticle loaded with gold nanorod and liquid perflurocarbon; 2) GNR group:gold nanorod ; 3) control group:PLGA nanoparticle unloaded with gold nanorod.A pulsed laser system was used to trigger the three samples.The photoacoustic image and time-signal intensity kinetics were acquired by the photoacoustic microscope.The optical microscope was used to observe the image after the vaporization.Results The gold nanoparticle was successfully prepared,the average size of the gold nanoparticle was 504.9 nm.after triggered by the pulsed laser system,the vaporized image of the GNP group could be observed by the optical microscope.The photoacoustic signal was detected in both GNP and GNR groups,and the signal intensity increased along with the concentration of the GNR.However,the photoacoustic signal of PLGA group was not detected.The photoacoustic signal kinetics of GNP group showed a descending trend from high signal amplitude to steadystate.The GNR group photoacoustic signal kinetics only showed a steady-state signal amplitude.Conclusions The PLGA nanoparticle loaded with gold nanorod and liquid perflurocarbon emerged a phase transient which produces a strong photoacoustic signal after triggered by pulsed laser system.This kind of phenomenon leads the nanoparticle to be a better photoacoustic contrast agent and lays a foundation for in vivo research and photothermal therapy in vivo.

Objective To prepare a kind of superparamagnetic iron oxide (SPIO) and doxorubicin loaded multifunctional polymer microbubbles (MPMBs),and to explore its potential application as an ultrasound(US)/magnetic resonance (MR) imaging contrast agent in vitro.Methods The MPMBs and normal polymer microbubbles (PMBs) were made by double emulsion and freeze-drying methods.The physical property,drug encapsulation efficiency and the drug-loading efficiency of MPMBs were determined,and the release property and US/MR imaging enhancement of MPMBs were observed.Results The MPMBs had a regular shape and narrow size distribution.The drug encapsulation efficiency was (60.20±2.69) ％,and the drug-loading efficiency was (6.02 ± 0.27) ％.The in vitro release experiment showed that ultrasound can promote the release of doxorubicin in MPMBs.US imaging in vitro showed that the enhancement of MPMBs was better than PMBs,and MR imaging in vitro conformed that MPMBs could well enhance MR imaging.Conclusions The MPMBs is a multifunctional contrast agent with the treatment function as well as US/MR dual-mode imaging enhancement effect.