Ceusia-Breast: computer-aided diagnosis with contrast enhanced ultrasound image analysis for breast lesions.

BACKGROUND: In recent years, contrast-enhanced ultrasonography (CEUS) has been used for various applications in breast diagnosis. The superiority of CEUS over conventional B-mode imaging in the ultrasound diagnosis of the breast lesions in clinical practice has been widely confirmed. On the other hand, there have been many proposals for computer-aided diagnosis of breast lesions on B-mode ultrasound images, but few for CEUS. We propose a semi-automatic classification method based on machine learning in CEUS of breast lesions. METHODS: The proposed method extracts spatial and temporal features from CEUS videos and breast tumors are classified as benign or malignant using linear support vector machines (SVM) with combination of selected optimal features. In the proposed method, tumor regions are extracted using the guidance information specified by the examiners, then morphological and texture features of tumor regions obtained from B-mode and CEUS images and TIC features obtained from CEUS video are extracted. Then, our method uses SVM classifiers to classify breast tumors as benign or malignant. During SVM training, many features are prepared, and useful features are selected. We name our proposed method "Ceucia-Breast" (Contrast Enhanced UltraSound Image Analysis for BREAST lesions). RESULTS: The experimental results on 119 subjects show that the area under the receiver operating curve, accuracy, precision, and recall are 0.893, 0.816, 0.841 and 0.920, respectively. The classification performance is improved by our method over conventional methods using only B-mode images. In addition, we confirm that the selected features are consistent with the CEUS guidelines for breast tumor diagnosis. Furthermore, we conduct an experiment on the operator dependency of specifying guidance information and find that the intra-operator and inter-operator kappa coefficients are 1.0 and 0.798, respectively. CONCLUSION: The experimental results show a significant improvement in classification performance compared to conventional classification methods using only B-mode images. We also confirm that the selected features are related to the findings that are considered important in clinical practice. Furthermore, we verify the intra- and inter-examiner correlation in the guidance input for region extraction and confirm that both correlations are in strong agreement.

Significance of Shear Wave Dispersion Slope Values Before Versus After Biliary Drainage in Patients With Obstructive Jaundice: A Single-Center Prospective Observational Cohort Study.

ABSTRACT: The shear wave dispersion (SWD) slope has become available in the clinical practice and is related to tissue viscosity. However, clinical evaluation using SWD was not yet performed for obstructive jaundice. We aimed to evaluate the change of SWD values between before and after biliary drainage in patients with obstructive jaundice. This prospective observational cohort study evaluated 20 patients with obstructive jaundice who underwent biliary drainage. The SWD and liver elasticity values were measured before versus after biliary drainage, comparing between days -5 and 0 (day 0), days 1 and 3 (day 2), and days 6 and 8 (day 7). The mean ± SD values of SWD measured at day 0, day 2, and day 7 were 15.3 ± 2.7, 14.2 ± 3.3, and 13.3 ± 2.4 m/s/kHz, respectively. Dispersion slope values were decreased significantly from day 0 to day 2, from day 2 to day 7, and from day 0 to day 7 ( P < 0.05). Liver elasticity levels and serum hepatobiliary enzymes were additionally decreased significantly over time after biliary drainage. The correlations between SWD and liver elasticity values were strong ( r = 0.91, P < 0.01). In conclusion, t he SWD values decreased significantly over time after biliary drainage concomitant with liver elasticity.

Sonographic findings of immunoglobulin G4-related sclerosing sialadenitis.

PURPOSE: We evaluated the sonographic findings of immunoglobulin G4-related sclerosing sialadenitis (IgG4-SS). METHODS: Nineteen patients with IgG4-SS and 12 healthy volunteers (controls) were enrolled. The following sonographic features were evaluated: (1) enlargement of the submandibular gland by measurement of the longitudinal diameter and thickness; (2) the contour texture of the submandibular gland (smooth or rough); (3) the internal echo texture, categorized into three sonographic patterns (homogeneous, multiple hypoechoic nodule, and diffuse hypoechoic); and (4) quantitative color Doppler signaling. RESULTS: The longitudinal diameter and the thickness (mean ± SD) of the submandibular gland were significantly greater in patients than in controls (p = 0.005 and p < 0.001, respectively). Contour roughness was seen in 62.9 and 8.3 % of patients and controls (p < 0.001), respectively. Homogeneous echo textures alone were seen in controls, whereas multiple hypoechoic nodule patterns were seen in 60 % of the patients, and diffuse hypoechoic patterns were seen in 40 %. Color Doppler signaling (mean ± SD) was significantly higher in patients as compared with controls (p < 0.001). CONCLUSION: Patients could be distinguished from healthy volunteers using four distinctive sonographic findings, suggesting that ultrasonography would be a useful diagnostic tool for IgG4-SS.

Reliability of peripheral intraneural microhemodynamics evaluation by using contrast-enhanced ultrasonography.

PURPOSE: The purpose of the study was to validate the reliability of quantitative intraneural enhancement patterns by using contrast-enhanced ultrasonography (CEUS). METHODS: Nine asymptomatic wrists underwent a total of three CEUS examinations each conducted at 1-month intervals. The CEUS enhancement pattern of median nerves was quantitatively evaluated. The area under the time-intensity curve was calculated by placing the regions of interest at the proximal, center, and distal regions of the median nerve. An intra-class correlation coefficient for intra-observer, inter-observer, and inter-examination reproducibility was calculated. RESULTS: The intra- and inter-observer reproducibility was almost perfect. Inter-examination reproducibility of the proximal, center, and distal regions was 0.891, 0.614, and 0.535, respectively. In this study, we found that the reproducibility of the distal and center regions of the median nerve in the carpal tunnel was lower than that of the proximal region. CONCLUSION: High intra-observer, inter-observer, and inter-examination reproducibility of CEUS was obtained in the evaluation of the intraneural enhancement pattern when the region of interest was placed in the proximal region of the median nerve.

Screening for target Rabs of TBC (Tre-2/Bub2/Cdc16) domain-containing proteins based on their Rab-binding activity.

It has recently been proposed that the TBC (Tre2/Bub2/Cdc16) domain functions as a GAP (GTPase-activating protein) domain for small GTPase Rab. Because of the large number of Rab proteins in mammals, however, most TBC domains have never been investigated for Rab-GAP activity. In this study we established panels of the GTP-fixed form of 60 different Rabs constructed in pGAD-C1, a yeast two-hybrid bait vector. We also constructed a yeast two-hybrid prey vector (pGBDU-C1) that harbors the cDNA of 40 distinct TBC proteins. Systematic investigation of 2400 combinations of 60 GTP-fixed Rabs and 40 TBC proteins by yeast two-hybrid screening revealed that seven TBC proteins specifically and differentially interact with specific Rabs (e.g. OATL1 interacts with Rab2A; FLJ12085 with Rab5A/B/C; and Evi5-like with Rab10). Measurement of in vitro Rab-GAP activity revealed that OATL1 and Evi5-like actually possess significant Rab2A- and Rab10-GAP activity, respectively, but that FLJ12085 do not display Rab5A-GAP activity at all. These results indicate that specific interaction between TBC protein and Rab would be a useful indicator for screening for the target Rabs of some TBC/Rab-GAP domains, but that there is little correlation between the Rab-binding activity and Rab-GAP activity of other TBC proteins.

Synaptotagmin VII is targeted to dense-core vesicles and regulates their Ca2+ -dependent exocytosis in PC12 cells.

It has recently been proposed that synaptotagmin (Syt) VII functions as a plasma membrane Ca2+ sensor for dense-core vesicle exocytosis in PC12 cells based on the results of transient overexpression studies using green fluorescent protein (GFP)-tagged Syt VII; however, the precise subcellular localization of Syt VII is still a matter of controversy (plasma membrane versus secretory granules). In this study we established a PC12 cell line "stably expressing" the Syt VII-GFP molecule and demonstrated by immunocytochemical and immunoelectron microscopic analyses that the Syt VII-GFP protein is localized on dense-core vesicles as well as in other intracellular membranous structures, such as the trans-Golgi network and lysosomes. Syt VII-GFP forms a complex with endogenous Syts I and IX, but not with Syt IV, and it colocalize well with Syts I and IX in the cellular processes (where dense-core vesicles are accumulated) in the PC12 cell line. We further demonstrated by an N-terminal antibody-uptake experiment that Syt VII-GFP-containing dense-core vesicles undergo Ca2+ -dependent exocytosis, the same as endogenous Syt IX-containing vesicles. Moreover, silencing of Syt VII-GFP with specific small interfering RNA dramatically reduced high KCl-dependent neuropeptide Y secretion from the stable PC12 cell line (approximately 60% of the control cells), whereas the same small interfering RNA had little effect on neuropeptide Y secretion from the wild-type PC12 cells (approximately 85-90% of the control cells), indicating that the level of endogenous expression of Syt VII molecules must be low. Our results indicate that the targeting of Syt VII-GFP molecules to specific membrane compartment(s) is affected by the transfection method (transient expression versus stable expression) and suggested that Syt VII molecule on dense-core vesicles functions as a vesicular Ca2+ sensor for exocytosis in endocrine cells.