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Emelianov SY Chen X O'Donnell M Knipp B Myers D Wakefield TW Rubin JM 《Ultrasound in medicine & biology》2002,28(6):757-767
Deep venous thrombosis (DVT), and its sequela, pulmonary embolism (PE), is the leading cause of preventable in-hospital mortality in the USA and other developed countries. After it is detected, acute clots must be differentiated from chronic DVT for appropriate treatment. However, there are no reliable thrombus staging methods presently available in clinical practice. In this study, we tested the hypothesis that blood clots can be detected and staged using a triplex ultrasound (US) test. Triplex US is based on a "gold standard" duplex US technique augmented by US-based reconstructive elasticity imaging. Fibrin-composed blood clots harden with development and organization. By imaging clot elasticity, it may be possible to both detect and differentiate clots and, therefore, provide an urgently needed noninvasive means of DVT staging. 相似文献
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Gunin AG Emelianov VU Tolmachev AS 《European journal of obstetrics, gynecology, and reproductive biology》2003,107(1):62-67
BACKGROUND: It has been shown that long-term glucocporticoid administration to chronically estradiol-treated mice decreases uterine weight, proliferation in all uterine tissues, the number of perpendicularly oriented mitoses in uterine epithelia and the incidence of atypical endometrial hyperplasia. However, mechanisms of chronic glucocorticoid action on estrogen-dependent processes in the uterus are unclear. METHODS AND RESULTS: Results of present research showed that adding of glucocorticoid dexamethasone (in drinking water, 2mg/l) to estradiol-treated mice led to a decrease in the level of glucocorticoid receptor, to an increase in levels of estrogen receptor-alpha, beta-catenin and glycogen synthase kinase-3beta in uterine tissues of ovariectomized mice at 30, 60 and 90 days of the treatment. When vehicle was used instead estradiol, dexamethasone did not produce detectable changes in all parameters tested at all periods of observation. CONCLUSION: Results allow to conclude that estrogen and glucocorticoid receptors, beta-catenin and glycogen synthase kinase-3beta are involved in estrogen-dependent changes in uterine morphology and hyperplasia formation. 相似文献
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Steele DD Chenevert TL Skovoroda AR Emelianov SY 《Physics in medicine and biology》2000,45(6):1633-1648
This article presents a method for measuring three-dimensional mechanical displacement and strain fields using stimulated echo MRI. Additional gradient pulses encode internal displacements in response to an externally applied deformation. By limiting the mechanical transition to the stimulated echo mixing time, a more accurate static displacement measurement is obtained. A three-dimensional elasticity reconstruction within a region of interest having a uniform shear modulus along its boundary is performed by numerically solving discretized elasticity equilibrium equations. Data acquisition, strain measurements and reconstruction were performed using a silicone gel phantom containing an inclusion of known elastic properties. A comparison between two-dimensional and three-dimensional reconstructions from simulated and experimental displacement data shows higher accuracy from the three-dimensional reconstruction. The long-term objective of this work is to provide a method for remotely palpating and elastically quantitating manually inaccessible tissues. 相似文献
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Gunin AG Emelianov VU Mironkin IU Morozov MP Tolmachev AS 《European journal of obstetrics, gynecology, and reproductive biology》2004,114(1):83-91
OBJECTIVES: It is suggested that the Wnt/beta-catenin pathway plays a role in the regulation of estrogen action in the uterus. However, this suggestion has not been proved. Lithium can mimic increased activity of the Wnt/beta-catenin pathway by blocking the activity of glycogen synthase kinase-3beta. There are no data on the effects of lithium on estrogen-dependent processes in the uterus. This work was therefore aimed to examine the action of lithium on proliferative and morphogenetic reactions in the uterus under short- and long-term estrogen treatments. STUDY DESIGN: Ovariectomized mice received estradiol dipropionate (2 microg per 100g; s.c.) once a week or vehicle and drank tap water with 0.05% lithium chloride or plain tap water for 2 or 30 days. RESULTS: In animals treated with estradiol and lithium for a month, the incidence of atypical endometrial hyperplasia was significantly higher. In animals treated with estradiol and lithium for 2 days or for a month, uterine mass, the number of mitotic cells and BrdU-labelled cells in luminal epithelium, glandular epithelium, stromal and myometrial cells was markedly greater, whereas the levels of estrogen receptors-alpha, beta-catenin and glycogen synthase kinase-3beta were markedly lower in all uterine compartments, than in those in mice received estradiol with no lithium to drink. CONCLUSIONS: Lithium treatment results in an increase in estradiol-induced proliferative and morphogenetic changes in the uterus. This action of lithium is associated with decreased expression of estrogen receptors-alpha, beta-catenin and glycogen synthase kinase-3beta in the uterus. 相似文献
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Brian W. Pogue Vadim Backman Stanislav Emelianov Christoph K. Hitzenberger Peter So Valery Tuchin 《Biomedical optics express》2012,3(11):2771
The guest editors introduce a feature issue containing papers based on research presented at the BIOMED 2012 conference.OCIS code: (170.0170) Medical optics and biotechnologyFor the past two decades, the Optical Society of America has been organizing biennial topical meetings under the conference name BIOMED [1]. The presentations covered in this meeting are at the heart of biomedical optics, and the diversity of meeting themes covered has continued to grow with the application areas of the field. The papers published in this issue of Biomedical Optics Express are contributions from authors who presented their work at this past meeting, in April/May 2012 held in Miami FL.The meeting covered four full days of talks and posters in the areas of (1) Biomedical Applications of Digital Holography, (2) BioNanophotonic and Molecular Probes, (3) Optical Microscopy Techniques, (4) Photoacoustic Imaging and Spectroscopy, (5) Optical Coherence Tomography, (6) Optical Imaging and Tomography, and (7) Optical Spectroscopy. The conference was chaired by Dr. Claude A. Boccara (France), Dr. Xingde Li (USA) and Dr. Lev T. Perelman (USA). The intent of the conference is to bring together people to present in all of these areas, and every two years to repeat this conference. It has run every two years in Florida since 2002 and is planned to continue again in 2014 and beyond.This issue bands together 25 papers submitted to Biomedical Optics Express from talks and posters that were presented at the BIOMED 2012 conference. 相似文献
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Shah J Park S Aglyamov S Larson T Ma L Sokolov K Johnston K Milner T Emelianov SY 《Journal of biomedical optics》2008,13(3):034024
Photothermal therapy is a noninvasive, targeted, laser-based technique for cancer treatment. During photothermal therapy, light energy is converted to heat by tumor-specific photoabsorbers. The corresponding temperature rise causes localized cancer destruction. For effective treatment, however, the presence of photoabsorbers in the tumor must be ascertained before therapy and thermal imaging must be performed during therapy. This study investigates the feasibility of guiding photothermal therapy by using photoacoustic imaging to detect photoabsorbers and to monitor temperature elevation. Photothermal therapy is carried out by utilizing a continuous wave laser and metal nanocomposites broadly absorbing in the near-infrared optical range. A linear array-based ultrasound imaging system is interfaced with a nanosecond pulsed laser to image tissue-mimicking phantoms and ex-vivo animal tissue before and during photothermal therapy. Before commencing therapy, photoacoustic imaging identifies the presence and spatial location of nanoparticles. Thermal maps are computed by monitoring temperature-induced changes in the photoacoustic signal during the therapeutic procedure and are compared with temperature estimates obtained from ultrasound imaging. The results of our study suggest that photoacoustic imaging, augmented by ultrasound imaging, is a viable candidate to guide photoabsorber-enhanced photothermal therapy. 相似文献
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Jonathan M Rubin Hua Xie Kang Kim William F Weitzel Stanislav Y Emelianov Salavat R Aglyamov Thomas W Wakefield Andrew G Urquhart Matthew O'Donnell 《Journal of ultrasound in medicine》2006,25(9):1179-1186
OBJECTIVE: The purpose of this study was to assess the ability of sonographic elasticity imaging to distinguish acute from chronic deep venous thrombosis (DVT). METHODS: Fifty-four patients, 26 with acute DVT and 28 with chronic DVT, were studied, and we analyzed the data in 46 patients, 23 with acute (mean age, 5.7 days) and 23 with chronic (>8 months) DVT. Scanning was performed with a 5-MHz linear array transducer during continuous freehand external deformation of each thrombus using the ultrasound scan head. The strains in the thrombi were normalized to the average strain between the skin surface and the back wall of the vein. Relative thrombus echogenicity was measured by comparing the echogenicity of the thrombus with that of the adjacent arterial lumen. Statistical analyses were performed with the Mann-Whitney U test and receiver operating characteristic analysis. RESULTS: The median normalized strain magnitude for the acute cases was 2.75, with an interquartile range of 2.4 to 3.71, whereas the median normalized strain magnitude for the chronic cases was 0.94, with interquartile range of 0.48 to 1.36. The difference was highly significant (P < 10(-7)). The area under the receiver operating characteristic curve (A(z)) was 0.97 +/- 0.02 (SE). The echogenicity difference between the populations was highly significant (P < 10(-5)), with A(z) of 0.92 +/- 0.04. The difference between the A(z) values was not significant (P > .05). CONCLUSIONS: In this population, sonographic elasticity imaging performs at least as well as thrombus echogenicity. Thrombus aging using elasticity imaging would be particularly helpful in evaluating symptoms in patients with post-thrombotic syndrome. 相似文献
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Bo Wang Andrei Karpiouk Doug Yeager James Amirian Silvio Litovsky Richard Smalling Stanislav Emelianov 《Ultrasound in medicine & biology》2012
We present a preliminary study demonstrating the capability of ultrasound-guided intravascular photoacoustic (IVPA) imaging to visualize the depth-resolved distribution of lipid deposits in atherosclerotic plaques in vivo. Based on the characteristic optical absorption of lipid in the near infrared wavelength range, IVPA imaging at a single, 1720 nm, wavelength was used to provide a spatially-resolved, direct measurement of lipid content in atherosclerotic arteries. By overlaying an IVPA image with a spatially co-registered intravascular ultrasound (IVUS) image, the combined IVPA/IVUS image was used to visualize lipid distribution within the vessel wall. Ultrasound-guided IVPA imaging was performed in vivo in the abdominal aorta of a Watanabe heritable hyperlipidemic (WHHL) rabbit. Subsequently, the excised rabbit aorta filled with a solution of red blood cells (RBC) was then imaged ex vivo, and histology was obtained in the section adjacent to the imaged cross-section. To demonstrate the potential for future clinical application of IVPA/IVUS imaging, a sample of diseased human right coronary artery (RCA) was also imaged. Both in vivo and ex vivo IVPA images clearly showed the distribution of lipid in the atherosclerotic vessels. In vivo IVPA imaging was able to identify diffuse, lipid-rich plaques in the WHHL rabbit model of atherosclerosis. Furthermore, IVPA imaging at a single wavelength was able to identify the lipid core within the human RCA ex vivo. Our results demonstrate that ultrasound-guided IVPA imaging can identify lipid in atherosclerotic plaques in vivo. Importantly, the IVPA/IVUS images were obtained in presence of luminal blood and no saline flush or balloon occlusion was required. Overall, our studies suggest that ultrasound-guided IVPA imaging can potentially be used for depth-resolved visualization of lipid deposits within the anatomical context of the vessel wall and lumen. Therefore, IVUS/IVPA imaging may become an important tool for the detection of rupture-prone plaques. 相似文献
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