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Ultrasound Treatment (ultrasound + treatment)
Selected AbstractsComplementary roles of platelets and coagulation in thrombus formation on plaques acutely ruptured by targeted ultrasound treatment: a novel intravital modelJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2009M. J. E. KUIJPERS Summary.,Background:,Atherothrombosis is a major cause of cardiovascular events. However, animal models to study this process are scarce. Objectives:,We describe the first murine model of acute thrombus formation upon plaque rupture to study atherothrombosis by intravital fluorescence microscopy. Methods:,Localized rupture of an atherosclerotic plaque in a carotid artery from Apoe,/, mice was induced in vivo using ultrasound. Rupture of the plaque and formation of localized thrombi were verified by two-photon laser scanning microscopy (TPLSM) in isolated arteries, and by immunohistochemistry. The thrombotic reaction was quantified by intravital fluorescence microscopy. Results:,Inspection of the ultrasound-treated plaques by histochemistry and TPLSM demonstrated local damage, collagen exposure, luminal thrombus formation as well as intra-plaque intrusion of erythrocytes and fibrin. Ultrasound treatment of healthy carotid arteries resulted in endothelial damage and limited platelet adhesion. Real-time intravital fluorescence microscopy demonstrated rapid platelet deposition on plaques and formation of a single thrombus that remained subocclusive. The thrombotic process was antagonized by thrombin inhibition, or by blocking of collagen or adenosine diphosphate receptor pathways. Multiple thrombi were formed in 70% of mice lacking CD40L. Conclusions:,Targeted rupture of murine plaques results in collagen exposure and non-occlusive thrombus formation. The thrombotic process relies on platelet activation as well as on thrombin generation and coagulation, and is sensitive to established and novel antithrombotic medication. This model provides new possibilities to study atherothrombosis in vivo. [source] Ultrasonic treatment of waste activated sludgeENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 2 2006Raf Dewil Abstract Activated sludge processes are key technologies to treat wastewater. These biological processes produce huge amounts of waste activated sludge (WAS), now commonly called biosolids. Mechanical, thermal, and/or chemical WAS conditioning techniques have been proposed to reduce the sludge burden. The ultrasonic treatment of WAS is quite novel. The present paper reports on extensive investigations using an ultrasonic treatment of WAS, to study its potential to meet one or all of four objectives: (1) reduce WAS quantities; (2) achieve a better dewaterability; (3) provoke a release of soluble chemical oxygen demand (COD) from the biosolids, preferably transformed into biodegradable organics; and (4) possibly destroy the filamentous microorganisms responsible for sludge bulking. Although meeting these objectives would help to solve the problems cited, the energy consumption could be a considerable drawback: the paper will thus assess whether all or some objectives are met, and at what operational cost. A literature survey defines the occurring phenomena (cavitation) and the important operation parameters [such as frequency, duration, specific energy input (SE)]. The experiments are carried out in a batch reactor of volume up to 2.3 L. The ultrasonic equipment consisted of a generator, a converter, and a sonotrode, supplied by Alpha Ultrasonics under the brand name of Telsonic. Three different kinds of sludge were tested, with different concentrations of dry solids (DS) between approximately 3.5 and 14 g DS/L WAS. Ultrasonic energy was introduced in a continuous manner (against possible pulsed operation). The major operational parameters studied include duration of the ultrasonic treatment and specific energy input. The applied frequency was set at 20 kHz. The release of COD from the WAS phase into the filtrate phase is a function of the specific energy input with yields of nearly 30% achievable at SE values of 30,000 kJ/kg DS. A major fraction of the COD is transformed into biodegradable organics (BOD). The reduction in DS fraction of the sludge is proportional to the COD release rates. Although the DS content is reduced, the dewaterability of the sludge is not improved. This reflects itself in increased filtration times during vacuum filtration and in increased values of the capillary suction time (CST). This more difficult dewaterability is the result of considerably reduced floc sizes, offering an extended surface area: more surface water is bound (CST increases) and the filterability decreases as a result of clogging of the cake. To reach the same dryness as for the untreated cake, the required dosage of polyelectrolyte is nearly doubled when the SE of the ultrasound treatment is increased from 7500 to 20,000 kJ/kg DS. The ultrasonic reduction of filamentous WAS organisms is not conclusive and very little effect is seen at low intensities and short treatment durations. Microscopic analysis of the WAS identified the dominant presence of Actynomyces. The release of soluble COD and BOD certainly merit further research. © 2006 American Institute of Chemical Engineers Environ Prog, 2006 [source] Nanocomposite Microcontainers with High Ultrasound SensitivityADVANCED FUNCTIONAL MATERIALS, Issue 7 2010Tatiana A. Kolesnikova Abstract A water suspension of nanocomposite microcapsules with embedded ZnO nanoparticles in the capsule shell is reported. The microcapsule morphology is characterized by confocal microscopy, TEM, SEM, and AFM before and after ultrasound treatment. A remarkably high capsule sensitivity to ultrasound is evidenced, and it is observed to grow with increasing number of ZnO nanoparticle layers in the nanocomposite shell. This effect is correlated with the mechanical properties of microcapsules measured with AFM. [source] Comparison of three conservative treatment protocols in carpal tunnel syndromeINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2006O. Baysal Summary The aim of this study was to investigate and compare the therapeutic effect of three different combinations in the conservative treatment of carpal tunnel syndrome (CTS) by means of clinical and electrophysiological studies. The combinations included tendon- and nerve-gliding exercises in combination with splinting, ultrasound treatment in combination with splinting and the combination of ultrasound, splinting, tendon- and nerve-gliding exercises. A total 28 female patients (56 wrists) with clinical and electrophysiologic evidence of bilateral CTS were studied. In all patient groups, the treatment combinations were significantly effective immediately and 8 weeks after the treatment. The results of the long-term patient satisfaction questionnaire revealed that symptomatic improvement is more prominent in the group treated with splinting, exercise and ultrasound therapy combination. Our results suggest that a combination of splinting, exercise and ultrasound therapy is a preferable and an efficacious conservative type of treatment in CTS. [source] REMOVAL OF LIPID FROM SURFACES OF ROASTED PEANUTS BY SONICATION AS ASSESSED BY FLUORESCENCE AND SCANNING ELECTRON MICROSCOPYJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2010PETER WAMBURA ABSTRACT Peanut oil migrates to the outer surface during roasting, where it comes into contact with oxygen, leading to the oxidation reactions. Because of its cleaning effect, power ultrasound (sonication) was used for removing surface lipid of roasted peanuts. Georgia green runner-type peanuts were roasted at 178C for 15 min. Roasted peanuts were subjected to lipid extraction in n-hexane by sonication. Fluorescent and electron scanning micrographs revealed that the surface of sonicated peanuts was free of oil stains, as opposed to that of freshly roasted peanuts. These results showed that power ultrasound could remove the lipids from peanut surfaces very effectively. Details of microstructure of sonicated peanuts as was observed using scanning electron microscope reveal that 10 min sonication was sufficient to extract most of the lipids on the roasted peanut surfaces. Fluorescence and scanning electron microscopy are useful in peanut analysis because they can detect lipids in low concentration. PRACTICAL APPLICATIONS There is increasing interest of quick procedures to examine the surfaces of roasted peanut samples after undergoing treatments, such as removal of lipids. This research demonstrated the significant use of fluorescent and scanning electron microscopes to quickly study the extent of lipid removal from the surface of roasted peanuts after power ultrasound treatment (sonication). [source] Ultrasound-induced modifications of cytoskeletal components in osteoblast-like SAOS-2 cellsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2009Joerg Hauser Abstract In clinical and experimental studies an acceleration of fracture healing and increased callus formation induced by low-intensity pulsed ultrasound (LIPUS) has been demonstrated. The exact molecular mechanisms of ultrasound treatment are still unclear. In this study ultrasound transmitted cytoskeletal and growth rate changes of SAOS-2 cells were examined. Osteoblast-like cell lines (SAOS-2) were treated using low-intensity pulsed ultrasound. Cytoskeletal changes were analyzed using rhodamine phalloidine for f-actin staining and indirect immunofluorescence techniques with different monoclonal antibodies against several tubulin modifications. To examine changes of cell number after ultrasound treatment cell counts were done. Significant changes in cytoskeleton structure were detected compared to controls, including an enhancement of stress fiber formation combined with a loss of cell migration after ultrasound application. We further observed that sonication altered the proportion of the more stable microtubules to the more labile microtubule subclass. The labile tyrosinated microtubules appeared highly enhanced, whereas the amount of the more stable acetylated microtubules was remarkably diminished. All these observations were quantified by fluorometric measurements. The centrosomal ,-tubulin was frequently scattered throughout the cell's cytoplasm, giving rise to additional polyglu-positive microtubular asters, which induced multipolar spindles, leading either to aneuploid mini-or giant cells. Moreover, a significant increase of cell number was noticed in the sonicated group. These experiments demonstrate that ultrasound treatment increases cell number and leads to significant changes of the cytoskeletal structure and composition in vitro. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:286,294, 2009 [source] Skin permeability enhancement by low frequency sonophoresis: Lipid extraction and transport pathwaysJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2003R. Alvarez-Román Abstract The objective of this study was to shed light on the mechanism(s) by which low-frequency ultrasound (20 KHz) enhances the permeability of the skin. The physical effects on the barrier and the transport pathway, in particular, were examined. The amount of lipid removed from the intercellular domains of the stratum corneum following sonophoresis was determined by infrared spectroscopy. Transport of the fluorescent probes nile red and calcein, under the influence of ultrasound, was evaluated by laser-scanning confocal microscopy. The results were compared with the appropriate passive control data and with data obtained from experiments in which the skin was exposed simply to the thermal effects induced by ultrasound treatment. A significant fraction (,30%) of the intercellular lipids of the stratum corneum, which are principally responsible for skin barrier function, were removed during the application of low-frequency sonophoresis. Although the confocal images from the nile red experiments were not particularly informative, ultrasound clearly and significantly (again, relative to the corresponding controls) facilitated transport of the hydrophilic calcein via discrete permeabilized regions, whereas other areas of the barrier were apparently unaffected. Lipid removal from the stratum corneum is implicated as a factor contributing the observed permeation enhancement effects of low-frequency ultrasound. However, microscopic observations imply that sonophoresis induces localized (aqueous?) permeation pathways at discrete sites. © 2003 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 92:1138,1146, 2003 [source] Complementary roles of platelets and coagulation in thrombus formation on plaques acutely ruptured by targeted ultrasound treatment: a novel intravital modelJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2009M. J. E. KUIJPERS Summary.,Background:,Atherothrombosis is a major cause of cardiovascular events. However, animal models to study this process are scarce. Objectives:,We describe the first murine model of acute thrombus formation upon plaque rupture to study atherothrombosis by intravital fluorescence microscopy. Methods:,Localized rupture of an atherosclerotic plaque in a carotid artery from Apoe,/, mice was induced in vivo using ultrasound. Rupture of the plaque and formation of localized thrombi were verified by two-photon laser scanning microscopy (TPLSM) in isolated arteries, and by immunohistochemistry. The thrombotic reaction was quantified by intravital fluorescence microscopy. Results:,Inspection of the ultrasound-treated plaques by histochemistry and TPLSM demonstrated local damage, collagen exposure, luminal thrombus formation as well as intra-plaque intrusion of erythrocytes and fibrin. Ultrasound treatment of healthy carotid arteries resulted in endothelial damage and limited platelet adhesion. Real-time intravital fluorescence microscopy demonstrated rapid platelet deposition on plaques and formation of a single thrombus that remained subocclusive. The thrombotic process was antagonized by thrombin inhibition, or by blocking of collagen or adenosine diphosphate receptor pathways. Multiple thrombi were formed in 70% of mice lacking CD40L. Conclusions:,Targeted rupture of murine plaques results in collagen exposure and non-occlusive thrombus formation. The thrombotic process relies on platelet activation as well as on thrombin generation and coagulation, and is sensitive to established and novel antithrombotic medication. This model provides new possibilities to study atherothrombosis in vivo. [source] Acceleration of ALA-induced PpIX fluorescence development in the oral mucosaLASERS IN SURGERY AND MEDICINE, Issue 3 2003Sirintra Charoenbanpachon Abstract Background and Objectives The development of 5-aminolevulinic acid (ALA)-induced tissue fluorescence is optimal 2,4 hours after ALA application. Goal of this work was to develop a means of accelerating oral topical ALA-induced tissue fluorescence. Study Design/Materials and Methods In 300 hamsters, DMBA (9,10 dimethyl-1,2-benzanthracene) cheek pouch carcinogenesis produced dysplasia in 3,5 weeks. Topical application of 20% ALA in Eucerin was followed by localized ultrasound treatment (1, 3.3 MHz) in 150 animals. In 75 animals, ALA was applied in an Oral Pluronic Lecithin Organogel (OPLO,an absorption enhancer) vehicle. Seventy-five animals received only topical ALA in Eucerin. Hamsters were sacrificed and cryosections underwent fluorescence measurements, histological evaluation, 20,180 minutes after ALA application. One-way ANOVA detected independent effects of pathology on laser-induced fluorescence (LIF). Two-way ANOVA tested for independent effect of pathology and of OPLO, ultrasound, and interaction effects. Results Ultrasound significantly (P,<,0.05) accelerated tissue fluorescence development. Conclusions Low-frequency ultrasound can accelerate ALA-induced fluorescence development. Lasers Surg. Med. 32:185,188, 2003. © 2003 Wiley-Liss, Inc. [source] Stage-specific effects of osmolarity of a culture medium on development of pig oocytes and miniature pig somatic cell nuclear transfer embryos activated by ultrasound treatmentANIMAL SCIENCE JOURNAL, Issue 4 2010Yamato MIZOBE ABSTRACT Whether high osmolarity of a culture medium at the early culture stage affects the development of pig oocytes and miniature pig somatic cell nuclear transfer (SCNT) embryos activated by ultrasound was examined. When oocytes were cultured in modified porcine zygote medium-3 (mPZM-3) with increased NaCl to 138 mmol/L (mPZM-3+NaCl; 326 mOsm) or 50 mmol/L sucrose (mPZM-3+sucrose; 318 mOsm) for the first 2 days and then cultured in normal mPZM-3 (273 mOsm) for 5 days, the cleavage and blastocyst formation rates were significantly (P < 0.05) higher than those of oocytes cultured in mPZM-3 for 7 days. The cleavage and blastocyst formation rates of SCNT embryos cultured in mPZM-3+NaCl for the first 2 days and then cultured in mPZM-3 for 5 days were also significantly (P < 0.05) higher than those of embryos cultured in mPZM-3 for 7 days. These results showed that the high osmolarity of a culture medium induced by increasing NaCl concentration during the first 2 days improves the development of pig oocytes and miniature pig SCNT embryos activated by ultrasound. [source] | ||||||||||||||||