Correlation between nonlinear subharmonic scattering of ultrasound contrast agent microbubbles and ambient pressure is expected to be used for local brain tissue pressure monitoring. Although high-frequency ultrasound has achieved high-resolution imaging of intracranial microvessels, the research on high-frequency subharmonic scattering characteristics of microbubbles is insufficient at present, which restricts the research progress of estimating local brain tissue pressure based on high-frequency subharmonic scattering of microbubbles. Therefore, under the excitation of 10 MHz high-frequency ultrasound, the effects of different acoustic pressures and ambient pressures on the high-frequency subharmonic scattering characteristics of three different ultrasound contrast agents including SonoVue, Sonazoid and Huashengxian were investigated in this in vitro study. Results showed that the subharmonic scattering amplitudes of the three microbubbles increased with the increase of ambient pressure at the peak negative acoustic pressures of 696, 766 and 817 kPa, and there was a favorable linear correlation between subharmonic amplitude and ambient pressure. Under the above three acoustic pressures, the highest correlation coefficient of SonoVue was 0.948 ( P = 0.03), the highest sensitivity of pressure measurement was 0.248 dB/mm Hg and the minimum root mean square error (RMSE) was 2.64 mm Hg. Sonazoid's highest correlation coefficient was 0.982 ( P < 0.01), the highest sensitivity of pressure measurement was 0.052 dB/mm Hg and the minimum RMSE was 1.51 mm Hg. The highest correlation coefficient of Huashengxian was 0.969 ( P = 0.02), the highest sensitivity of pressure measurement was 0.098 dB/mm Hg and the minimum RMSE was 2.00 mm Hg. The above in vitro experimental results indicate that by selecting ultrasound contrast agent microbubbles and optimizing acoustic pressure, the correlation between high-frequency subharmonic scattering of microbubbles and ambient pressure can be improved, the sensitivity of pressure measurement can be upgraded, and the measurement error can be reduced to meet the clinical demand for local brain tissue pressure measurement, which provided an important experimental basis for subsequent research in vivo.
Contrast Media ; Microbubbles ; Ultrasonography/methods*

BR55 is an ultrasound contrast agent targeting vascular endothelial growth factor receptor 2,which can be used to detect tumor neovascularization and improve the diagnostic accuracy.Overseas researchers have used BR55 for human ultrasound molecular imaging,which showed good safety and tolerance.We reviewed the research progress on BR55 applied in the evaluation of tumor neovascularization from the composition,characteristics,animal experiments,and clinical studies of BR55.
Animals ; Contrast Media ; Humans ; Microbubbles ; Molecular Imaging/methods* ; Neovascularization, Pathologic/diagnostic imaging* ; Ultrasonography/methods* ; Vascular Endothelial Growth Factor Receptor-2/analysis*

Ultrasound contrast agent microbubbles combined with low frequency ultrasound named as low-frequency ultrasound-targeted microbubble destruction technology has become an effective and non-invasive anti-tumor therapy for deep tumors.It can enhance the efficacies of chemotherapy,gene therapy,immunotherapy,and anti-angiogenic therapy by improving cell membrane permeability and destroying tumor neovasculature.It can be applied to sonodynamic therapy and realize multimodal synergistic therapy on the basis of nanoparticles,which increases the anti-tumor efficiency and offers a promising target therapy for tumors.
Contrast Media ; Genetic Therapy ; Humans ; Microbubbles ; Neoplasms ; Ultrasonography

Animals ; Bony Callus ; Diagnostic Imaging ; Dogs ; Fracture Fixation ; Fracture Healing ; Microbubbles ; Miners ; Muscle, Skeletal ; Osteotomy ; Perfusion ; Radiography ; Ultrasonography ; Ultrasonography, Doppler

Contrast-enhanced ultrasound (CEUS) is a powerful technique for differentiating focal liver lesions (FLLs) without the risks of potential nephrotoxicity or ionizing radiation. In the diagnostic algorithm for FLLs on CEUS, washout is an important feature, as its presence is highly suggestive of malignancy and its characteristics are useful in distinguishing hepatocellular from non-hepatocellular malignancies. Interpreting washout on CEUS requires an understanding that microbubble contrast agents are strictly intravascular, unlike computed tomography or magnetic resonance imaging contrast agents. This review explains the definition and types of washout on CEUS in accordance with the 2017 version of the CEUS Liver Imaging Reporting and Data System and presents their applications to differential diagnosis with illustrative examples. Additionally, we propose potential mechanisms of rapid washout and describe the washout phenomenon in benign entities.
Carcinoma, Hepatocellular ; Contrast Media ; Diagnosis ; Diagnosis, Differential ; Information Systems ; Liver ; Magnetic Resonance Imaging ; Microbubbles ; Neoplasm Metastasis ; Radiation, Ionizing ; Ultrasonography

Contrast-enhanced ultrasonography (CEUS) using microbubble ultrasonography contrast agent can show the vascular structure and unique contrast enhancement patterns of focal liver lesions, including hepatocellular carcinoma (HCC). CEUS shows three phases, similar to a vascular pattern on computer tomography (CT), and typical arterial enhancement and portal or late phase washout in HCC. CEUS can show real-time images without nephrotoxicity or radiation hazard and can be used as guidance for loco-regional treatment and estimation of treatment response of HCC. In addition, some data recently revealed the usefulness of CEUS in the early estimation of response to anti-cancer pharmacological (i.e., sorafenib) therapy in advanced HCC. Although CEUS has limitations in clinical practice and more investigation is needed for its validation, it is recommended as a main diagnostic modality in a few major clinical practice guidelines for HCC. Thus, greater understanding of CEUS is necessary to extend its application in real practice for diagnosis and management of diseases.
Carcinoma, Hepatocellular ; Diagnosis ; Liver ; Microbubbles ; Ultrasonography

Magnetic resonance-guided focused ultrasound (MRgFUS) is an emerging new technology with considerable potential to treat various neurological diseases. With refinement of ultrasound transducer technology and integration with magnetic resonance imaging guidance, transcranial sonication of precise cerebral targets has become a therapeutic option. Intensity is a key determinant of ultrasound effects. High-intensity focused ultrasound can produce targeted lesions via thermal ablation of tissue. MRgFUS-mediated stereotactic ablation is non-invasive, incision-free, and confers immediate therapeutic effects. Since the US Food and Drug Administration approval of MRgFUS in 2016 for unilateral thalamotomy in medication-refractory essential tremor, studies on novel indications such as Parkinson's disease, psychiatric disease, and brain tumors are underway. MRgFUS is also used in the context of blood-brain barrier (BBB) opening at low intensities, in combination with intravenously-administered microbubbles. Preclinical studies show that MRgFUS-mediated BBB opening safely enhances the delivery of targeted chemotherapeutic agents to the brain and improves tumor control as well as survival. In addition, BBB opening has been shown to activate the innate immune system in animal models of Alzheimer’s disease. Amyloid plaque clearance and promotion of neurogenesis in these studies suggest that MRgFUS-mediated BBB opening may be a new paradigm for neurodegenerative disease treatment in the future. Here, we review the current status of preclinical and clinical trials of MRgFUS-mediated thermal ablation and BBB opening, described their mechanisms of action, and discuss future prospects.
Alzheimer Disease ; Blood-Brain Barrier ; Brain ; Brain Neoplasms ; Essential Tremor ; High-Intensity Focused Ultrasound Ablation ; Immune System ; Magnetic Resonance Imaging ; Microbubbles ; Models, Animal ; Neurodegenerative Diseases ; Neurogenesis ; Parkinson Disease ; Plaque, Amyloid ; Sonication ; Therapeutic Uses ; Transducers ; Ultrasonography ; United States Food and Drug Administration

The development of low-frequency ultrasound imaging technology and the improvement of ultrasound contrast agent production technology mean that they play an increasingly important role in tumor therapy. The interaction between ultrasound and microbubbles and their biological effects can transfer and release microbubbles carrying genes and drugs to target tissues, mediate the apoptosis of tumor cells, and block the embolization of tumor microvasculature. With the optimization of ultrasound parameters, the development of targeted microbubbles, and the emergence of various composite probes with both diagnostic and therapeutic functions, low-frequency ultrasound combined with microbubble contrast agents will bring new hope for clinical tumor treatment.
Antineoplastic Agents/therapeutic use* ; Apoptosis ; Autophagy ; Cell Membrane Permeability ; Cell Proliferation ; Contrast Media/administration & dosage* ; Drug Delivery Systems ; Humans ; Microbubbles ; Microcirculation ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Neoplasms/therapy* ; Patient Safety ; Transfection ; Ultrasonic Therapy/methods*

OBJECTIVE: To analyze the specificity and sensitivity of the modified microbubble test in identifying the peripherally inserted central venous catheters (PICC) tip based on the chest X-ray location as the "gold standard", and to find out an accurate and noninvasive PICC tip positioning method that can save time and cost. METHODS: Convenient sampling method was conducted. The patients under PICC guided by ultrasound in intensive care unit (ICU) or PICC clinic of the First Affiliated Hospital of Nanchang University from August 2017 to February 2018 were enrolled. All patients were followed up by ultrasound guided PICC catheter placement, modified microbubble test and chest X-ray localization. The relationship between the density of microbubbles in modified microbubble test and the location of PICC tip in chest X-ray localization was analyzed. Using chest X-ray localization as the "gold standard", the diagnostic evaluation indexes such as specificity and sensitivity of PICC tip identification by modified microbubble test were calculated. RESULTS: A total of 120 patients were enrolled during the study period, excluding those who refused to participate in the study, unclear right atrial ultrasound, conscious intolerance, unclear chest X-ray, and finally 108 patients completed the modified microbubble test and chest X-ray tip localization. According to the chest X-ray localization results of 108 patients, 69 patients (63.9%) were in ideal locations, 33 (30.6%) were in dissatisfactory position, and 6 (5.5%) were in malposition. There was no significant difference in gender, age, tube placement, depth of catheterization, placement of catheterization room, and catheterization among the three groups. In the modified microbubble test, there were 74 patients (68.5%) with grade I microbubble, 25 (23.2%) with grade II microbubble, and 9 (8.3%) with grade III microbubble. There was a correlation between microbubble density and the tip position of the catheter, showing a moderate intensity correlation, and the contingency coefficient was 0.662. The sensitivity of the modified microbubble test for PICC tip positioning was 95.7% (66/69), the specificity was 89.7% (35/39), the rate of missed diagnosis was 4.4% (3/69), the misdiagnosis rate was 10.3% (4/39), the positive predictive value was 94.3% (66/70), the negative predictive value was 92.1% (35/38), and the Youden index was 0.85. The consistency between the two methods was good, and the Kappa value was 0.86. CONCLUSIONS Compared with the chest X-ray localization method, the modified microbubble test method has high sensitivity and specificity in identifying PICC in the position, and the operation is simple, noninvasive, with less time and low cost. The modified microbubble test can be used as a screening test for PICC tip position, especially in ICU. When there are technical limitations or suspicious patient, further chest X-ray is necessary.
Catheterization, Central Venous ; Catheterization, Peripheral ; Central Venous Catheters ; Humans ; Microbubbles ; Ultrasonography

Background: Signal transducer and activator of transcription 3 (STAT3) was strongly expressed and activated in psoriatic keratinocytes (KCs) and correlated with the severity of psoriasis. The study aimed to investigate the effects of STAT3 small interfering RNA (siRNA) combined with ultrasonic irradiation and SonoVue microbubbles on the proliferation and apoptosis in KCs of psoriatic lesions and the relative mechanisms. Methods: Psoriatic KCs were transfected under four experimental conditions: (1) STAT3 siRNA carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles (LUS group); (2) STAT3 siRNA only carried by Lipofectamine 3000 (L group); (3) the negative control of siRNA carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles (siRNA-NC); (4) not treated as Blank. Cell Counting Kit-8 assay was used to evaluate the cell proliferation. Cell cycle analysis was detected with cycle test Plus DNA reagent kit associated with flow cytometer. FITC Annexin V apoptosis detection kit associated with flow cytometer was applied for apoptosis analysis. Fluo calcium indicator associated with flow cytometer was used to analyze intracellular free calcium concentration ([Ca]). The expressions of cyclin D1 and Bcl-xL were detected both at the mRNA level by real-time reverse transcription-polymerase chain reaction (RT-PCR) and at the protein level by Western blotting. The obtained data were statistically evaluated by two-way analysis of variance. Results: STAT3 siRNA inhibited the growth of KCs in a time-dependent manner showing the highest proliferation inhibition in LUS group with proliferation ratio of 45.38% ± 5.85% at 72h (P < 0.05 vs. L group, siRNA-NC, or Blank). STAT3 siRNA induced an altered cell cycle distribution of KCs showing the highest increases in G2/M-phase population up to 18.06% ± 0.36% in LUS group (P < 0.05 vs. L group, siRNA-NC, or Blank). STAT3 siRNA induced late apoptosis of KCs with the highest late apoptosis percentage of 22.87% ± 1.28% in LUS group (P < 0.05 vs. L group, siRNA-NC, or Blank). STAT3 siRNA induced the elevation of [Ca]of KCs with the highest calcium fluorescence intensity mean of 1213.67 ± 60.51 in LUS group (P < 0.05 vs. L group, siRNA-NC, or Blank). STAT3 siRNA induced the downregulation of cyclin D1 and Bcl-xL expressions of KCs at mRNA and protein levels with the lowest expressions in LUS group with cyclin D1 expression of 51.81% ± 9.58% and 70.17% ± 4.22% at mRNA level and at protein level, respectively, and with Bcl-xL expression of 37.58% ± 4.92% and 64.06% ± 7.78% at mRNA level and at protein level, respectively (P < 0.05 vs. L group, siRNA-NC, or Blank). Conclusions STAT3 siRNA inhibited the growth and induced the apoptosis in psoriatic KCs likely partly through altering cell cycle distribution, elevating [Ca], and downregulating cyclin D1 and Bcl-xL expressions. Silencing the target gene STAT3 in psoriatic KCs with siRNA combined with ultrasonic irradiation and microbubbles would contribute to a significant innovation as a new clinical therapy for psoriasis.
Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Keratinocytes ; Microbubbles ; Phospholipids ; Psoriasis ; therapy ; RNA Interference ; RNA, Small Interfering ; STAT3 Transcription Factor ; metabolism ; Sulfur Hexafluoride ; Ultrasonics