Quantitative Evaluation of Biceps Brachii Muscle by Shear Wave Elastography in Stroke Patients.

Purpose: The present study aimed to investigate the differences in muscle size and shear wave speed (SWS) values of biceps brachii muscle (BBM) between stroke survivors and healthy controls. Methods: This study comprised 61 stroke survivors and 24 healthy subjects, examined at Guangzhou First People's Hospital within one year. Each participant underwent ultrasonic examinations for recording some specific measurement indicators, including muscle thickness, cross-sectional area (CSA), and shear wave speed (SWS) of BBM. The muscular tension of the paretic arm was scored using the modified Ashworth scale (MAS). These above-mentioned indexes were compared between stroke survivors and healthy controls. Also, the correlations among SWS and MAS scores were assessed. Results: When the lifting arm angle was set for 45°, the CSA and muscle thickness of BBM were obviously decreased in the paretic arms of stroke subjects compared to the non-paretic arms as well as the arms of healthy controls. Moreover, the paretic arms had obviously higher SWS than the non-paretic arms and the healthy arms at 45° or 90°. When the angles of paretic arms were lifted at 90° and 45°, respectively, a positive correlation was established between MAS and SWS. Conclusion: Ultrasonic examination assessing muscle thickness, CSA, and SWS of the BBM could be used as a means of assessment of the paretic arms of stroke survivors.

Application of color Doppler ultrasound combined with Doppler imaging artifacts in the diagnosis and estimate of congenital hypertrophic pyloric stenosis.

Congenital Hypertrophic Pyloric Stenosis (CHPS) is a disease condition that is caused as a result of pylorus wall hypertrophy and hyperplasia. In this study, we used color Doppler flow imaging (CDFI) and Doppler artifacts technique to observe the blood flow of hypertrophic pylorus tissue and the dynamic imaging of liquid passing through the pyloric canal in CHPS infants. 65 cases of CHPS infants and 50 infants without CHPS served as control group. We found that there were statistically significant differences between the blood flow grade of muscular layer and mucosal layer between CHPS and control infants, but no significant differences were observed in the same group. Doppler artifacts technique demonstrated the whole process of contrast agent flow through pyloric canal was directly observed in 35 of 65 subjects, and the internal diameter of the pyloric canal was 1.93 ± 0.33mm.Conclusion that CDFI combined with color Doppler artifacts technique was proved to be effective to observe the distribution feature and blood flow grade in each layer of pyloric canal in CHPS patients. This method provides the evidence for judging the degree of pyloric stenosis clinically, and furnishes the basis of therapy along with its clinical significance and good application value.

Synergistic effects of negative-charged nanoparticles assisted by ultrasound on the reversal multidrug resistance phenotype in breast cancer cells.

We have fabricated a negative-charged nanoparticle (Heparin-Folate-Tat-Taxol NP, H-F-Tat-T NP) with dual ligands, tumor targeting ligand folate and cell-penetrating peptide Tat, to deliver taxol presenting great anticancer activity for sensitive cancer cells, while it fails to overcome multidrug resistance (MDR) in MCF-7/T cells (taxol-resistant breast cancer cells). Ultrasound (US) can increase the sensitivity of positive-charged NPs thereby making it possible to reverse MDR through inducing NPs' drug release. However, compared with the negative-charged NPs, positive-charged NPs may cause higher toxic effect. Hence, the combination of negative-charged NPs and US may be an efficient strategy for overcoming MDR. The conventional procedure to treat with NPs followed by US exposure possibly destruct multifunctional NPs resulting in its bioactivity inhibition. Herein, we have further improved the operating approach to eliminate US mechanical damage and keep the integrity of negative-charged NPs: cells are exposed to US with microbubbles (MBs) prior to the treatment of H-F-Tat-T NPs. Superior to the conventional method, US sonoporation affects the physiological property of cancer cells while preventing direct promotion of drug release from NPs. The results of the present study displayed that US in condition (1MHz, 10% duty cycle, duration of 80s, US intensity of 0.6W/cm2 and volume ratio of medium to MBs 20:1) combined with H-F-T-Tat-T NPs can achieve optimal reversal MDR effect in MCF-7/T cells. Mechanism study further disclosed that the individual effect of US was responsible for the enhancement of cell membrane permeability, inhibition of cell proliferation rate and down-regulation of MDR-related genes and proteins. Simultaneously, US sonoporation on resistant cancer cells indirectly increased the accumulation of NPs by inducing endosomal escape of negative-charged NPs. Taken together, the overcoming MDR ability for the combined strategy was achieved by the synergistic effect from individual function of NPs, physiological changes of resistant cancer cells and behavior changes of NPs caused by US.

[Photocatalytic Degradation Kinetics and Mechanism of Monoazo Dye Acid Yellow 17 by UV/TiO2 in Aqueous Solution].

In order to explore the removal methods, transformation, environmental fate, effect and potential risk of dyes in environmental water, monoazo dye acid yellow 17 (AY17) was selected as model compound to investigate the degradation possibility in different advance oxidation processes (AOPs), and the degradation efficiencies followed the order of UV/H2O2

Correlation of virtual touch tissue quantification and liver biopsy in a rat liver fibrosis model.

Liver fibrosis assessment is very important to the treatment of chronic liver disease. In the present study, Virtual Touch Tissue Quantification (VTQ) and eSie Touch™ elasticity imaging techniques were used to examine the rat liver fibrosis model. Rat liver fibrosis was induced with thioacetamide and the degree of liver fibrosis was determined using pathological diagnosis as a gold standard. The right lobe of the liver was also examined with the VTQ and eSie Touch™ techniques. The VTQ and serological results were correlated and analyzed. The results were compared with those obtained from liver biopsies to investigate the accuracy and diagnostic value of eSie Touch™ and VTQ on the classification of liver fibrosis in rats. A total of 30 successful modeling cases were obtained, with a success rate of 86%. The mean acoustic radiation force impulse (ARFI) elastography­VTQ values were 1.08, 1.51, 1.88 and 2.50 m/sec for the normal and F1/F2, F3 and F4 fibrosis groups, respectively. A significant correlation (r = 0.969) was identified between the ARFI measurements and the degree of fibrosis assessed by pathological examination (P<0.001). The histological staging results correlated with those of the eSie Touch™ elasticity imaging of the biopsy site (r = 0.913, P<0.001). The predictive values of ARFI for various stages of fibrosis were as follows: F≥1 and 2 ­ cut­off >1.250 m/sec (when Vs >1.250 m/sec, the pathological grading was ≥F1/F2) [Area under receiver operating characteristic (AUROC) = 1.00], F≥3 ­ cut­off >1.685 m/sec (when Vs >1.685 m/sec, the pathological grading was ≥F3; AUROC = 1.00) and F≥4 ­ cut­off >2.166 m/sec (when Vs >2.166 m/sec, the pathological grading is cirrhosis; AUROC = 1.00). In conclusion, the eSie Touch™ elasticity imaging and VTQ techniques may be successfully adopted to assess the extent of liver stiffness. These techniques are expected to replace liver biopsy.

Hemostatic effects of microbubble-enhanced low-intensity ultrasound in a liver avulsion injury model.

OBJECTIVES: Microbubble-enhanced therapeutic ultrasound (MEUS) can block the blood flow in the organs. The aim of this study was to evaluate the hemostatic effect of microbubble-enhanced pulsed, low-intensity ultrasound in a New Zealand White rabbit model of avulsion trauma of the liver. The therapeutic ultrasound (TUS) transducer was operated with the frequency of 1.2 MHz and an acoustic pressure of 3.4 MPa. Microbubble-(MB) enhanced ultrasound (MEUS) (n = 6) was delivered to the distal part of the liver where the avulsion was created. Livers were treated by TUS only (n = 4) or MB only (n = 4) which served as controls. Bleeding rates were measured and contrast enhanced ultrasound (CEUS) was performed to assess the hemostatic effect, and liver hemoperfusion before and after treatment. Generally, bleeding rates decreased more than 10-fold after the treatment with MEUS compared with those of the control group (P<0.05). CEUS showed significant declines in perfusion. The peak intensity value and the area under the curve also decreased after insonation compared with those of the control group (P<0.05). Histological examination showed cloudy and swollen hepatocytes, dilated hepatic sinusoids, perisinusoidal spaces with erythrocyte accumulation in small blood vessels, obvious hemorrhage around portal areas and scattered necrosis in liver tissues within the insonation area of MEUS Group. In addition, necrosis was found in liver tissue 48 h after insonation. We conclude that MEUS might provide an effective hemostatic therapy for serious organ trauma such as liver avulsion injury.

Perfusion heterogeneity in breast tumors for assessment of angiogenesis.

OBJECTIVES: The purpose of this study was to investigate the perfusion heterogeneity of malignant and benign breast tumors and assay their vascular architecture changes and molecular expression, thereby evaluating the relevance between imaging and histologic characteristics of angiogenesis. METHODS: Real-time grayscale contrast-enhanced sonography was performed in 310 women with 317 breast tumors. The enhancement patterns and perfusion parameters for malignant and benign tumors were analyzed by contrast-enhanced sonography with microvascular imaging and quantitative time-intensity curve analysis. Structural characteristics were observed by light and electron microscopy. The microvessel density, vascular endothelial growth factor (VEGF) expression, and human kinase insert domain-containing receptor (KDR) expression for all tumors were assessed by immunohistochemical staining of CD31, KDR, and VEGF. RESULTS: Surgical pathologic analysis showed 163 malignant and 154 benign tumors. Significant morphologic differences, including perfusion defects, vessel distortion, vessel dilatation, and heterogeneous enhancement, were observed between the malignant and benign groups (P < .05). The mean perfusion parameters (peak intensity, ascending slope, area under the curve, and wash-out time) were greater in the malignant tumors (P < .05). There were significant differences in the peak intensity, ascending slope, area under the curve, and wash-out time between peripheral and central regions of the malignant tumors (P < .05) but none in the benign tumors. Vessels had various morphologic and distributional characteristics in the peripheral and central regions of the malignant tumors. The microvessel density and VEGF and KDR expression were significantly higher in the malignant group (P < .05), especially in the peripheral regions. CONCLUSIONS: Perfusion heterogeneity was closely associated with the tumor microvascular architecture and molecular expression. Perfusion features, especially regional morphologic and hemodynamic features, can provide valuable information for differentiating malignant from benign breast tumors.