Intraplaque neovascularization is a biomarker of vulnerable plaque. However, no data are available whether the increase in neovascularization within carotid plaques is a result of ischemia or an increase in adventitial vasa vasorum (VV).

To evaluate the VV signal in carotid vulnerable plaques.

Contrast-enhanced ultrasound (CEUS) examination was performed to examine changes in VV density in 47 patients with carotid plaque, and 21 patients received CT angiography (CTA) examination to assess the VV signal. In addition, a single-channel flow tissue model was fabricated for use in vitro studies to exclude pseudo-enhancement interferences in the distal wall of arteries by CEUS.

The intensities of adventitial VV behind carotid plaque were lower than that of adventitial VV at the same level adjacent to the plaque in both CEUS and CTA examinations (P < 0.05). In vitro study, the intensities of far wall increased as the microbubble concentration increased (P < 0.05). However, no significant differences of intensities of far wall were found between different thicknesses tubes at the concentration of microbubble concentrations of 0.3% and 0.5% (P ≥ 0.05).

The formation of intraplaque neovascularization in carotid arteries is associated with the adventitial VV, and ischemia of VV may be a potential mechanism for intraplaque neovascularization.

To evaluate accuracy and feasibility of a handheld ultrasound machine for measuring carotid artery intima-media thicknesses (CIMT) and hemodynamic parameters by different expertise levels of ultrasound operators.

The operators were divided into three groups based on the level of their medical expertise: ultrasound technician, sonographer, and nursing staff. Operators from each group measured the CIMT and hemodynamic parameters of 25 volunteers using both handheld ultrasound and a conventional ultrasound machine. The reliability and reproducibility of handheld ultrasound measurements of CIMT and hemodynamic parameters (peak systolic velocity (PSV), end-diastolic velocity (EDV)) in operators were analyzed.

After a period of training, there was no statistically significant difference between the mean CIMT measured using handheld ultrasound among the three operators (0.45 ± 0.09 mm, 0.50 ± 0.07 mm, 0.46 ± 0.08 mm, P > 0.05, respectively), as well as PSV (83.30 ± 15.42 cm/s, 76.28 ± 13.26 cm/s, 81.12 ± 21.21 cm/s, P > 0.05, respectively) and EDV (21.04 ± 4.12 cm/s, 21.87 ± 5.05 cm/s, 20.17 ± 5.90 cm/s, respectively, P > 0.05). Furthermore, there was a good repeatability and consistent of handheld ultrasound device in measuring mean CIMT in the ultrasound technician and sonographer groups (r = 0.662, 0.691, respectively, P < 0.01).

Under the premise of proper training, handheld ultrasound systems are feasible for rapid and primary assessment of carotid artery by operators with different levels of expertise.

To investigate the correlation between the DCE-CT imaging biomarkers and histological biomarkers of tumor angiogenesis in adrenal adenomas and non-adenomas for the enhancement mechanism of DCE-CT.

Forty-two patients with 45 adrenal masses including 27 adenomas and 18 non-adenomas diagnosed pathologically were enrolled in this study. The features of DCE-CT (imaging biomarkers) and tumor angiogenesis (histological biomarkers) in adrenal masses were evaluated, and their correlations were explored.

The enhanced features of DCE-CT in adrenal masses were classified: rapid washout group and slow washout group. Type A and C of time density (TD) curves, relative washout rate (Washr) ≥34%, and absolute washout rate (Washa) ≥43% belonged to the rapid group. In contrast, type B, D and E, Washr <34%, and Washa <43% belonged to the slow group. There was significant difference between the biomarkers of DCE-CT in adrenal masses. The rapid group was mainly found in adenomas, whereas the slow was mainly present in nonadenomas. The tumor angiogenesis, histological biomarkers, including microvessel density (MVD), vascular endothelial growth factor (VEGF), and microvascular ultrastructures demonstrated significant difference between the rapid and the slow washout group revealed by DCE-CT. The MVD and VEGF expression in rapid group were remarkably higher than those in slow group. Meanwhile, the tumor angiogenesis was also significantly different between adenomas and nonadenomas. The MVD and VEGF expression were also significantly higher in adenomas than those in nonadenomas. Furthermore, different microvascular ultrastructures were identified between adenomas and nonadenomas, which were in accordance with those between the rapid and the slow group. Microvascular ultrastructures in adrenal adenomas and/or the rapid group showed regular lumens and nonstenosis; more pinocytotic vesicles and fenestrations of endothelium; widening of the intercellular space; uniform thinning and better integrity of basal membrane; regular and uniform thinning, along with less stroma of extra vessel space. In comparison, opposite microvascular ultrastructures, in adrenal nonadenomas and/or the slow group.

The close correlation of DCE-CT imaging biomarkers and histological biomarkers of tumor angiogenesis was found between adrenal adenomas and nonadenomas. Tumor angiogenesis in adrenal adenomas and nonadenomas were shown the different enhancement characteristics at DCE-CT.

To evaluate the carotid viscoelasticity using ultrasound shear wave dispersion imaging (USWD) and determine its feasibility.

Fifty-three volunteers were recruited and divided into the group1 (≥50 years old) and group 2 (<50 years old). The shear wave elastic modulus (SWE-A_R and SWE-P_R) and shear wave dispersion indexes (SWD-A_R and SWD-P_R), which located at the anterior and posterior walls of the common carotid artery (CCA), were obtained by USWD, and compared with pulse wave velocity (PWV). Pearson correlation analysis was applied to analyze the related factors of viscoelasticity.

Before and after body mass index, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were adjusted, SWE-A_R, SWE-P_R, SWD-A_R and SWD-P_R were all higher in the group 2 than those of group 1 (all P < 0.05). In all subjects, SWE was negatively correlated with age, SBP, DBP and PWV, respectively (r = -0.282, -0.374, -0.321, -0.256 and all P < 0.05). The SWD was negatively correlated with PWV in the group 1, while positively correlated with SBP in the group 2 (r=-0.393 and r=0.366, all P < 0.05).

The viscoelasticity of arterial wall can be assessed by USWD. It provides a new way to describe arterial disease for clinical study.

The purpose of this study was to optimize ultrasound-targeted microbubble destruction (UTMD) on RAGE plasmid transfection in human coronary artery endothelial cells (HCAECs) and improve gene transfection efficiency in vitro.

SonoVue microbubble suspension was prepared and mixed with HCAECs, while the cells were adherent and suspended, respectively. After RAGE plasmids being added, they were exposed to ultrasonic irradiation for 10, 20, and 30 s by a therapeutic US machine with 0.4W, respectively. The samples with adherent HCAECs (adherent group) were irradiated directly, while the samples with suspended HCAECs (suspended group) were irradiated via the water. The combined effect of ultrasound and microbubble on RAGE plasmid transfection in HCAECs was evaluated by detecting protein expression of RAGE by western blot. In addition, the viability of the HCAECs was analyzed by CCK8 in order to explore the optimal transfection condition.

In suspension group, compared with control, the expression of RAGE was gradually increased from 5 to 20s, and decreased from 20 to 30s. The expression of RAGE peaked in 20s and indicated statistical significance. However, compared with the control, the expression of RAGE did not significantly increase with prolonged ultrasound irradiation in the adherent group. On the other hand, viability of the HCAECs did not decrease significantly with extended exposure time in both groups.

UTMD represents an efficient and safe method for the transfection of cells in suspension and optimal exposure.