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Sample records for heart wall region

  1. In vivo wall shear measurements within the developing zebrafish heart.

    Directory of Open Access Journals (Sweden)

    R Aidan Jamison

    Full Text Available Physical forces can influence the embryonic development of many tissues. Within the cardiovascular system shear forces resulting from blood flow are known to be one of the regulatory signals that shape the developing heart. A key challenge in investigating the role of shear forces in cardiac development is the ability to obtain shear force measurements in vivo. Utilising the zebrafish model system we have developed a methodology that allows the shear force within the developing embryonic heart to be determined. Accurate wall shear measurement requires two essential pieces of information; high-resolution velocity measurements near the heart wall and the location and orientation of the heart wall itself. We have applied high-speed brightfield imaging to capture time-lapse series of blood flow within the beating heart between 3 and 6 days post-fertilization. Cardiac-phase filtering is applied to these time-lapse images to remove the heart wall and other slow moving structures leaving only the red blood cell movement. Using particle image velocimetry to calculate the velocity of red blood cells in different regions within the heart, and using the signal-to-noise ratio of the cardiac-phase filtered images to determine the boundary of blood flow, and therefore the position of the heart wall, we have been able to generate the necessary information to measure wall shear in vivo. We describe the methodology required to measure shear in vivo and the application of this technique to the developing zebrafish heart. We identify a reduction in shear at the ventricular-bulbar valve between 3 and 6 days post-fertilization and demonstrate that the shear environment of the ventricle during systole is constantly developing towards a more uniform level.

  2. In vivo wall shear measurements within the developing zebrafish heart.

    Science.gov (United States)

    Jamison, R Aidan; Samarage, Chaminda R; Bryson-Richardson, Robert J; Fouras, Andreas

    2013-01-01

    Physical forces can influence the embryonic development of many tissues. Within the cardiovascular system shear forces resulting from blood flow are known to be one of the regulatory signals that shape the developing heart. A key challenge in investigating the role of shear forces in cardiac development is the ability to obtain shear force measurements in vivo. Utilising the zebrafish model system we have developed a methodology that allows the shear force within the developing embryonic heart to be determined. Accurate wall shear measurement requires two essential pieces of information; high-resolution velocity measurements near the heart wall and the location and orientation of the heart wall itself. We have applied high-speed brightfield imaging to capture time-lapse series of blood flow within the beating heart between 3 and 6 days post-fertilization. Cardiac-phase filtering is applied to these time-lapse images to remove the heart wall and other slow moving structures leaving only the red blood cell movement. Using particle image velocimetry to calculate the velocity of red blood cells in different regions within the heart, and using the signal-to-noise ratio of the cardiac-phase filtered images to determine the boundary of blood flow, and therefore the position of the heart wall, we have been able to generate the necessary information to measure wall shear in vivo. We describe the methodology required to measure shear in vivo and the application of this technique to the developing zebrafish heart. We identify a reduction in shear at the ventricular-bulbar valve between 3 and 6 days post-fertilization and demonstrate that the shear environment of the ventricle during systole is constantly developing towards a more uniform level.

  3. Cartan frames for heart wall fiber motion

    NARCIS (Netherlands)

    Samari, Babak; Aumentado-Armstrong, Tristan; Strijkers, Gustav J.; Froeling, Martijn; Siddiqi, Kaleem

    2017-01-01

    Current understanding of heart wall fiber geometry is based on ex vivo static data obtained through diffusion imaging or histology. Thus, little is known about the manner in which fibers rotate as the heart beats. Yet, the geometric organization of moving fibers in the heart wall is key to its

  4. Identification of the heart wall and chamber based on temporal change of ultrasonic scatterer distribution

    Science.gov (United States)

    Takahashi, Kohei; Taki, Hirofumi; Kanai, Hiroshi

    2017-07-01

    In most current methods for evaluating the cardiac function by ultrasound, the heart wall area is identified manually by an examiner. To eliminate examiner dependence and to improve usability, an automatic heart wall identification method is desirable. Identification based on only echogenicity often fails because of low echogenicity of some areas of the heart wall. In the present study, to determine more essential features, we focused on the relative temporal change of ultrasonic scatterer distribution and proposed three features for identification of the heart wall and the chamber: cross-correlation of RF signals, that of envelopes, and spatial dispersion of movement vectors in small regions. In an in vivo experiment, using echogenicity and the three features, we identified the heart wall and the chamber in the left ventricular long-axis view, resulting in criteria of separability J of 1.69, 1.40, and 3.02 using these features compared with the result of 0.979 using echogenicity.

  5. Regional wall movement of the left ventricle in coronary heat diseases

    International Nuclear Information System (INIS)

    Schad, N.

    1979-01-01

    The regional wall movement of the left ventriculus is a substantial criterion for the treatment of coronary heart diseases. The non-invasive and riskless intravenous injections of a bolus of Technetium 99m-Pertechnetat and the recording of the first passage through the heart allow to present the regional wall movement of the left ventriculus and, in addition, to make a statement on the haemodynamic feed back effects on lungs and the right heart. The congruency with the wall movement determined invasively, in the contrast substance angiocardiogram, is high both for the normokinesis and for hypo-, A - and dyskinesis (90-92%). The examination proved good in following groups of patients and makes the decision on the further proceding easier: 1) After myocardial infarction. 2) In ishaemia-ECG or persistent ST-elevation. 3) In unstable progressive angina pectoris. 4) In unclear breast aches and negative ECG on exertion. 5) For course control after conservative and surgial therapy. The myocardial reserve can be shown using a after nitroglycerin administration. An investigation on exertion can find out affected vessel territories in the circulation. (orig.) [de

  6. Improvement of Automated Identification of the Heart Wall in Echocardiography by Suppressing Clutter Component

    Science.gov (United States)

    Takahashi, Hiroki; Hasegawa, Hideyuki; Kanai, Hiroshi

    2013-07-01

    For the facilitation of analysis and elimination of the operator dependence in estimating the myocardial function in echocardiography, we have previously developed a method for automated identification of the heart wall. However, there are misclassified regions because the magnitude-squared coherence (MSC) function of echo signals, which is one of the features in the previous method, is sensitively affected by the clutter components such as multiple reflection and off-axis echo from external tissue or the nearby myocardium. The objective of the present study is to improve the performance of automated identification of the heart wall. For this purpose, we proposed a method to suppress the effect of the clutter components on the MSC of echo signals by applying an adaptive moving target indicator (MTI) filter to echo signals. In vivo experimental results showed that the misclassified regions were significantly reduced using our proposed method in the longitudinal axis view of the heart.

  7. S values for selected radionuclides and organs with the heart wall and heart contents as source organs

    International Nuclear Information System (INIS)

    Coffey, J.L.; Watson, E.E.

    1981-01-01

    The generalized heart model of MIRD Pamphlet No. 5, Revised has no separation of heart wall from heart contents, and no phi values were listed for heart as either a source or target organ. Because of this, the heart model of the heterogeneous phantom for dosimetry calculations was revised and a description of this model and specific absorbed fractions will be published in MIRD Pamphlet No. 13. The purpose of this study is to use the specific absorbed fractions from MIRD-13 and decay scheme data to produce tables of S values (absorbed dose per unit cumulated activity) for selected radionuclides with the heart wall and heart contents as the source organs. As in the MIRD reports the activity is assumed to be uniformly distributed in the source organs. The phi values for the photon energies of a given radionuclide were found by lineraly interpolating between the energies listed in MIRD-13. When the source and target are the same, all nonpenetrating radiations are assumed to be absorbed in the organ in which they originate. For organs with walls and with the contents as the source, the dose to the wall from nonpenetrating radiations is assumed to be half of the dose to the contents

  8. The thick left ventricular wall of the giraffe heart normalises wall tension, but limits stroke volume and cardiac output

    DEFF Research Database (Denmark)

    Smerup, Morten Holdgaard; Damkjær, Mads; Brøndum, Emil

    2016-01-01

    Giraffes - the tallest extant animals on Earth - are renowned for their high central arterial blood pressure, which is necessary to secure brain perfusion. The pressure which may exceed 300 mmHg has historically been attributed to an exceptionally large heart. Recently, this has been refuted...... by several studies demonstrating that the mass of giraffe heart is similar to that of other mammals when expressed relative to body mass. It remains enigmatic, however, how the normal-sized giraffe heart generates such massive arterial pressures.We hypothesized that giraffe hearts have a small...... intraventricular cavity and a relatively thick ventricular wall, allowing for generation of high arterial pressures at normal left ventricular wall tension. In nine anaesthetized giraffes (495±38 kg), we determined in vivo ventricular dimensions using echocardiography along with intraventricular and aortic...

  9. Simultaneous measurement of instantaneous heart rate and chest wall plethysmography in short-term, metronome guided heart rate variability studies: suitability for assessment of autonomic dysfunction.

    Science.gov (United States)

    Perring, S; Jones, E

    2003-08-01

    Instantaneous heart rate and chest wall motion were measured using a 3-lead ECG and an air pressure chest wall plethysmography system. Chest wall plethysmography traces were found to accurately represent the breathing pattern as measured by spirometry (average correlation coefficient 0.944); though no attempt was made to calibrate plethysmography voltage output to tidal volume. Simultaneous measurements of heart rate and chest wall motion were made for short periods under metronome guided breathing at 6 breaths per minute. The average peak to trough heart rate change per breath cycle (AVEMAX) and maximum correlation between heart rate and breathing cycle (HRBRCORR) were measured. Studies of 44 normal volunteers indicated clear inverse correlation of heart rate variability parameters with age (AVEMAX R = -0.502, P < 0.001) but no significant change in HRBRCORR with age (R = -0.115). Comparison of normal volunteers with diabetics with no history of symptoms associated with autonomic failure indicated significant lower heart rate variability in diabetics (P = 0.005 for AVEMAX) and significantly worse correlation between heart rate and breathing (P < 0.001 for HRBRCORR). Simultaneous measurement of heart rate and breathing offers the possibility of more sensitive diagnosis of autonomic failure in a simple bedside test and gives further insight into the nature of cardio-ventilatory coupling.

  10. Clinical significance of exercise-induced left ventricular wall motion abnormality occurring at a low heart rate

    International Nuclear Information System (INIS)

    Kimchi, A.; Rozanski, A.; Fletcher, C.; Maddahi, J.; Swan, H.J.; Berman, D.S.

    1987-01-01

    We studied the relationship between the heart rate at the time of onset of exercise-induced wall motion abnormality and the severity of coronary artery disease in 89 patients who underwent exercise equilibrium radionuclide ventriculography as part of their evaluation for coronary artery disease. Segmental wall motion was scored with a five-point system (3 = normal; -1 = dyskinesis); a decrease of one score defined the onset of wall motion abnormality. The onset of wall motion abnormality at less than or equal to 70% of maximal predicted heart rate had 100% predictive accuracy for coronary artery disease and higher sensitivity than the onset of ischemic ST segment depression at similar heart rate during exercise: 36% (25 of 69 patients with coronary disease) vs 19% (13 of 69 patients), p = 0.01. Wall motion abnormality occurring at less than or equal to 70% of maximal predicted heart rate was present in 49% of patients (23 of 47) with critical stenosis (greater than or equal to 90% luminal diameter narrowing), and in only 5% of patients (2 of 42) without such severe stenosis, p less than 0.001. The sensitivity of exercise-induced wall motion abnormality occurring at a low heart rate for the presence of severe coronary artery disease was similar to that of a deterioration in wall motion by more than two scores during exercise (49% vs 53%) or an absolute decrease of greater than or equal to 5% in exercise left ventricular ejection fraction (49% vs 45%)

  11. Cine MR imaging assessment of regional left ventricular systolic wall thickening in patients with remote myocardial infarction

    International Nuclear Information System (INIS)

    Pfugfelder, P.; White, R.D.; Sechtem, U.; Gould, R.G.; Higgins, C.B.

    1986-01-01

    Cine MR imaging, a new rapid imaging technique, was used to acquire transverse images of the heart at a rate of 16-30 frames per cardiac cycle. Left ventricular wall thickness was measured at end diastole and end systole in six regions in the midventricular section of 13 healthy subjects and seven patients with previously documented myocardial infarction. Mean percent systolic wall thickening (%SWT) was 51% +- 26% in healthy subjects. In patients, %SWT was -8% +- 22% in the infarct zone and 42% +- 22% in the normal myocardium. In addition to the qualitative information derived from the cinematic display, determination of regional %SWT by cine-MR imaging may be useful for quantifying regional left ventricular dysfunction

  12. SU-F-T-85: Energy Modulated Electron Postmastectomy Unreconstructed (PU) Chest Wall (CW) Irradiation Technique to Achieve Heart Sparing

    Energy Technology Data Exchange (ETDEWEB)

    Hong, L; Ballangrud, A; Mechalakos, J [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); McCormick, B [Memerial Sloan-Kettering Cancer Center, New York, NY (United States)

    2016-06-15

    Purpose: For left-sided PU patients requiring CW and nodal irradiation, sometimes partial wide tangents (PWT) are not feasible due to abnormal chest wall contour or heart position close to the anterior chest wall or unusual wide excision scar. We developed an energy modulated electron chest wall irradiation technique that will achieve heart sparing. Methods: Ten left-sided PU patients were selected for this dosimetry study. If PWT were used, the amount of the ipsilateral lung would be ranged 3.4 to 4.4 cm, and the amount of heart would be ranged 1.3 to 3.8 cm. We used electron paired fields that matched on the skin to achieve dose conformity to the chest wall. The enface electron fields were designed at extended SSD from a single isocenter and gantry angle with different energy beams using different cutout. Lower energy was used in the central chest wall part and higher energy was used in the periphery of the chest wall. Bolus was used for the electron fields to ensure adequate skin dose coverage. The electron fields were matched to the photon supra-clavicle field in the superior region. Daily field junctions were used to feather the match lines between all the fields. Target volumes and normal tissues were drawn according to institutional protocols. Prescription dose was 2Gy per fraction for a total 50Gy. Dose calculations were done with Eclipse EMC-11031 for Electron and AAA-11031 for photons. Results: Six patients were planned using 6/9MeV, three using 9/12MeV and one 6/12MeV. Target volumes achieved adequate coverage. For heart, V30Gy, V20Gy and Mean Dose were 0.6%±0.6%, 2.7%±1.7%, and 3.0Gy±0.8Gy respectively. For ipsilateral lung, V50Gy, V20Gy, V10Gy and V5Gy were 0.9%±1.1%, 34.3%±5.1%, 51.6%±6.3% and 64.1%±7.5% respectively. Conclusion: For left-sided PU patients with unusual anatomy, energy modulated electron CW irradiation technique can achieve heart sparing with acceptable lung dose.

  13. Evaluation of regional wall motion abnormalities of the heart. Comparison with Doppler tissue echocardiography, MR-tagging and levocardiography

    International Nuclear Information System (INIS)

    Kivelitz, D.E.; Enzweiler, C.N.H.; Hamm, B.; Borges, A.C.; Walde, T.; Rutsch, W.; Baumann, G.

    2004-01-01

    Purpose: To compare the visual analysis of magnetic resonance imaging (MRI) with the tagging technique and Doppler tissue echocardiography with invasive ventriculography in detecting and quantifying regional left ventricular wall motion abnormalities. Materials and Methods: Sixteen patients with coronary artery disease and a history of prior myocardial infarction underwent invasive ventriculography. Doppler tissue echocardiography and MR-tagging within one week. Regional wall motion abnormalities (WMA) were detected in all patients. WMA were graded as normal=1; hypokinetic=2; akinetic=3; or dyskinetic=4. For agreement between MRI, echocardiography, and ventriculography the kappa coefficient (κ) according to Cohen was calculated. Results: The kappa coefficient (κ) was 0.962 for agreement between MRI and echocardiography and 0.602 for agreement between MRI and ventriculography as well as between echocardiography and ventriculography. Conclusion: Reliable analysis of regional left ventricular wall motion abnormalities is feasible using visual analysis of MR-tagging. MRI and Doppler tissue echocardiography detect more WMA than invasive ventriculography and grade them as more severe. (orig.)

  14. Temporal Fourier transform of digital angiograms for left ventricular regional wall motion analysis

    International Nuclear Information System (INIS)

    Katayama, Kazuhiro; Guth, B.D.; Widmann, T.F.; Lee, Jong-Dae; Seitelberger, R.; Peterson, K.L.

    1988-01-01

    To determine whether or not the first harmonic of a temporal Fourier transform, applied pixel-by-pixel on time-intensity curves, can detect the subtle wall motion abnormalities due to ischemia, 6 dogs were instrumented with a micromanometer in the left ventricles, a hydraulic cuff occluder around the circumflex coronary artery, and sonomicrometers on the inferior (ischemic) and anterior (non-ischemic) walls. Left ventricular images, obtained after contrast injection via the pulmonary artery, were compared with dimension signals in control and 3 progressive levels of coronary stenosis (Stenosis I, II and III). Normalized, digital functional images (512 x 512 matrix, 256 shades of gray/pixel) were divided into anterior, apical, and inferior areas to acquire regional mean phase (degrees) and amplitude (intensity units) values. After inducing stenosis, phase in ischemic region significantly increased at all 3 levels of stenosis, whereas amplitude significantly decreased at Stenosis II and III. However, amplitude images showed clearly the topographic site of ischemia. There was a progressive increase in phase and decrease in amplitude in ischemic areas as the percent wall thickening (%WTh) fell (phase vs. %WTh: r = -0.55, p < 0.005; amplitude vs. %WTh: r = 0.71, p < 0.001). Heart rate and peak systolic pressure showed no significant changes during stenoses. We conclude that quantitative functional images, generated from a temporal Fourier transform, are sensitive to the detection of left ventricular regional wall motion abnormalities during mild, moderate, and severe degrees of ischemia. (author)

  15. Interventional heart wall motion analysis with cardiac C-arm CT systems

    International Nuclear Information System (INIS)

    Müller, Kerstin; Maier, Andreas K; Schwemmer, Chris; Hornegger, Joachim; Zheng, Yefeng; Wang, Yang; Lauritsch, Günter; Rohkohl, Christopher; Fahrig, Rebecca

    2014-01-01

    Today, quantitative analysis of three-dimensional (3D) dynamics of the left ventricle (LV) cannot be performed directly in the catheter lab using a current angiographic C-arm system, which is the workhorse imaging modality for cardiac interventions. Therefore, myocardial wall analysis is completely based on the 2D angiographic images or pre-interventional 3D/4D imaging. In this paper, we present a complete framework to study the ventricular wall motion in 4D (3D+t) directly in the catheter lab. From the acquired 2D projection images, a dynamic 3D surface model of the LV is generated, which is then used to detect ventricular dyssynchrony. Different quantitative features to evaluate LV dynamics known from other modalities (ultrasound, magnetic resonance imaging) are transferred to the C-arm CT data. We use the ejection fraction, the systolic dyssynchrony index a 3D fractional shortening and the phase to maximal contraction (ϕ i, max ) to determine an indicator of LV dyssynchrony and to discriminate regionally pathological from normal myocardium. The proposed analysis tool was evaluated on simulated phantom LV data with and without pathological wall dysfunctions. The LV data used is publicly available online at https://conrad.stanford.edu/data/heart. In addition, the presented framework was tested on eight clinical patient data sets. The first clinical results demonstrate promising performance of the proposed analysis tool and encourage the application of the presented framework to a larger study in clinical practice. (paper)

  16. Determination of left ventricular wall motility injury by factor analysis in patients with advanced ischemic heart disease

    International Nuclear Information System (INIS)

    Kasalicky, J.; Kidery, J.; Vavrejn, B.; Surova, H.; Malek, I.

    1989-01-01

    Left ventricular phase and amplitude images (Fourier analysis, PAI) and factor analysis images (FAI) from gated radionuclide ventriculography were obtained in 235 patients after myocardial infarction (MI) and in 44 patients with well documented ischemic heart disease (IHD) in order to assess areas of regional left ventricular motility injury (LVMI). The sensitivity of FAI for LVMI detection was higher than with PAI (36.3% vs 22.7% in patients without MI; 76.6% vs 68% in those after anterior MI; and 53.2% vs 31.9% after posterior MI, respectively). In 2.9% of all patients PAI were unclear due to small time activity amplitudes and heart rate irregularity, whereas FAI could be easily assessed. Significantly decreased left ventricular ejection fraction was observed predominantly after anterior MI in connection with distinct signs of LVMI in a large area of anterior wall or in the anteroseptal and/or apical region. Areas of LVMI could be sharply delineated in FAI; however, in contrast to PAI, FAI is unable to distinguish between dyskinetic and akinetic regions. The use of both PAI and FAI is recommended for more detailed detection of regional LVMI in patients with IHD. (orig.)

  17. Intraventricular filling under increasing left ventricular wall stiffness and heart rates

    Science.gov (United States)

    Samaee, Milad; Lai, Hong Kuan; Schovanec, Joseph; Santhanakrishnan, Arvind; Nagueh, Sherif

    2015-11-01

    Heart failure with normal ejection fraction (HFNEF) is a clinical syndrome that is prevalent in over 50% of heart failure patients. HFNEF patients show increased left ventricle (LV) wall stiffness and clinical diagnosis is difficult using ejection fraction (EF) measurements. We hypothesized that filling vortex circulation strength would decrease with increasing LV stiffness irrespective of heart rate (HR). 2D PIV and hemodynamic measurements were acquired on LV physical models of varying wall stiffness under resting and exercise HRs. The LV models were comparatively tested in an in vitro flow circuit consisting of a two-element Windkessel model driven by a piston pump. The stiffer LV models were tested in comparison with the least stiff baseline model without changing pump amplitude, circuit compliance and resistance. Increasing stiffness at resting HR resulted in diminishing cardiac output without lowering EF below 50% as in HFNEF. Increasing HR to 110 bpm in addition to stiffness resulted in lowering EF to less than 50%. The circulation strength of the intraventricular filling vortex diminished with increasing stiffness and HR. The results suggest that filling vortex circulation strength could be potentially used as a surrogate measure of LV stiffness. This research was supported by the Oklahoma Center for Advancement of Science and Technology (HR14-022).

  18. Thin walls in regions with vacuum energy

    Energy Technology Data Exchange (ETDEWEB)

    Garfinkle, D [Florida Univ., Gainesville, FL (USA). Dept. of Physics; Vuille, C [Embry-Riddle Aeronautical Univ., Prescott, AZ (USA). Dept. of Math/Physical Science

    1989-12-01

    The motion of a thin wall is treated in the case where the regions on either side of the wall have vacuum energy. This treatment generalises previous results involving domain walls in vacuum and also previous results involving the properties of false vacuum bubbles. The equation of state for a domain wall is{tau} = {sigma} where {tau} is the tension in the wall and {sigma} is the energy density. We consider the motion of a more general class of walls having equation of state {tau}{Gamma}{sigma} with 0{le}{Gamma}{le}1. Spherically symmetric and planar symmetric walls are examined. We also find the global structure of the wall spacetime. (author).

  19. Arterial wall mechanics as a function of heart rate: role of vascular smooth muscle

    International Nuclear Information System (INIS)

    Salvucci, Fernando Pablo; Schiavone, Jonathan; Craiem, Damian; Barra, Juan Gabriel

    2007-01-01

    Vascular wall viscoelasticity can be evaluated using a first-order lumped model. This model consists of a spring with elastic constant E and a dashpot with viscous constant η. More importantly, this viscoelastic model can be fitted in-vivo measuring arterial pressure and diameter. The aim of this work is to analyze the influence of heart rate over E and η. In two anesthetized sheep, diameter in thoracic aorta and intravascular pressure has been registered. The right atrium was connected to a programmable stimulator through a pair of pace-maker wires to produce changes in stimulation heart rate (HR) from 80 to 160 bpm. Additionally, local activation of vascular smooth muscle was induced with phenylephrine. After converting pressure and diameter signals into stress and strain respectively, E y η were calculated in control state and during muscle activation. The elastic modulus E did not present significant changes with heart rate. The viscous modulus η decreased 49% with a two-fold acceleration in heart rate from 80 to 160 bpm. However, the product η HR remained stable. The viscous modulus η increased 39% with smooth muscle activation. No significant pressure changes were registered during the experiment. The contractile action of vascular smooth muscle could contribute to increasing arterial wall viscosity. The decrease of η when HR increased might be related to smooth muscle relaxation mediated by endothelium activity, which was stimulated by flow increase. We conclude that HR can modulate arterial wall viscoelasticity through endothelium-dependent mechanisms

  20. Changes in dynamic embryonic heart wall motion in response to outflow tract banding measured using video densitometry

    Science.gov (United States)

    Stovall, Stephanie; Midgett, Madeline; Thornburg, Kent; Rugonyi, Sandra

    2016-11-01

    Abnormal blood flow during early cardiovascular development has been identified as a key factor in the pathogenesis of congenital heart disease; however, the mechanisms by which altered hemodynamics induce cardiac malformations are poorly understood. This study used outflow tract (OFT) banding to model increased afterload, pressure, and blood flow velocities at tubular stages of heart development and characterized the immediate changes in cardiac wall motion due to banding in chicken embryo models with light microscopy-based video densitometry. Optical videos were used to acquire two-dimensional heart image sequences over the cardiac cycle, from which intensity data were extracted along the heart centerline at several locations in the heart ventricle and OFT. While no changes were observed in the synchronous contraction of the ventricle with banding, the peristaltic-like wall motion in the OFT was significantly affected. Our data provide valuable insight into early cardiac biomechanics and its characterization using a simple light microscopy-based imaging modality.

  1. Determination of global and regional heart functions with minimum transit times

    International Nuclear Information System (INIS)

    Feinendegen, L.E.; Becker, V.; Vyska, K.; Freundlieb, C.; Bosiljanoff, P.

    1980-01-01

    The minimum transit time obviously represents the most constant flow parameter. By means of a constant, that was chosen to be 1.2 for cardiac flow, it is equal to the quotient of volume to flow and is also inversely related proportional to the fraction of ejection that is concerned. The first indicator passage through the heart is measured for the minimum cardiac transit time, whereby interesting regions were chosen for the two auricula, the two ventricula, the pulmonary artery and the aorta. The time activity characteristica obtained from the particular regions need a special smoothing by means of the gliding mean, so that the arrival times can easily be recognized. This way in one examination process the differences of arrival times respectively the minimal transit times can be obtained for each particular cardiac segment, the pulmonary circuit and the whole cardio-pulmonary circuit. The advantages of minimum cardiac transit time measurements are the simplicity and the speed of the noninvasive functional diagnostic with lower radiation load and accuracy and reproductability with low error limits, especially for the whole cardio-pulmonary MTT. The simultaneous acquisition of multiple cardiac segments is to emphasize a special way. For its particular values similar error widths were found as for the left ventricular function measurement with the triggered scintigraphy of the interior of the heart. A further advantage of the measurement is an almost problem-less application in body load. Therefore the MTT-measurement is especially useful for preventive diagnostics of coronary diseases. A combination of MTT-measurements of all segments of the small circuit with the triggered scintigraphy of the interior of the heart for analysis of regional left-ventricular ejection fractions and left-ventricular wall movements would essentially enrich the noninvasive cardiac diagnostics. (orig./APR) [de

  2. [Segmental wall movement of the left ventricle in healthy persons and myocardial infarct patients studied by a catheter-less nuclear medical method (camera-cinematography of the heart)].

    Science.gov (United States)

    Geffers, H; Sigel, H; Bitter, F; Kampmann, H; Stauch, M; Adam, W E

    1976-08-01

    Camera-Kinematography is a nearly noninvasive method to investigate regional motion of the myocard, and allows evaluation of the function of the heart. About 20 min after injection of 15-20 mCi of 99mTC-Human-Serum-Albumin, when the tracer is distributed homogenously within the bloodpool, data acquisition starts. Myocardial wall motion is represented in an appropriate quasi three-dimensional form. In this representation scars can be revealed as "silent" (akinetic) regions, aneurysms by asynchronic motion. Time activity curves for arbitrarily chosen regions can be calculated and give an equivalent for regional volume changes. 16 patients with an old infarction have been investigated. In fourteen cases the location and extent of regions with abnormal motion could be evaluated. Only two cases of a small posterior wall infarction did not show deviations from normal contraction pattern.

  3. Post mastectomy linac IMRT irradiation of chest wall and regional nodes: dosimetry data and acute toxicities

    International Nuclear Information System (INIS)

    Ma, Jinli; Li, Jiongyan; Xie, Jiang; Chen, Jian; Zhu, Chuanying; Cai, Gang; Zhang, Zhen; Guo, Xiaomao; Chen, Jiayi

    2013-01-01

    Conventional post-mastectomy radiation therapy is delivered with tangential fields for chest wall and separate fields for regional nodes. Although chest wall and regional nodes delineation has been discussed with RTOG contouring atlas, CT-based planning to treat chest wall and regional nodes as a whole target has not been widely accepted. We herein discuss the dosimetric characteristics of a linac IMRT technique for treating chest wall and regional nodes as a whole PTV after modified radical mastectomy, and observe acute toxicities following irradiation. Patients indicated for PMRT were eligible. Chest wall and supra/infraclavicular region +/−internal mammary nodes were contoured as a whole PTV on planning CT. A simplified linac IMRT plan was designed using either integrated full beams or two segments of half beams split at caudal edge of clavicle head. DVHs were used to evaluate plans. The acute toxicities were followed up regularly. Totally, 85 patients were enrolled. Of these, 45 had left-sided lesions, and 35 received IMN irradiation. Planning designs yielded 55 integrated and 30 segmented plans, with median number of beams of 8 (6–12). The integrated and segmented plans had similar conformity (1.41±0.14 vs. 1.47±0.15, p=0.053) and homogeneity indexes (0.13±0.01 vs. 0.14±0.02, p=0.069). The percent volume of PTV receiving >110% prescription dose was <5%. As compared to segmented plans, integrated plans typically increased V 5 of ipsilateral lung (p=0.005), and heart (p=0.001) in patients with left-sided lesions. Similarly, integrated plans had higher spinal cord D max (p=0.009), ipsilateral humeral head (p<0.001), and contralateral lung D mean (p=0.019). During follow-up, 36 (42%) were identified to have ≥ grade 2 radiation dermatitis (RD). Of these, 35 developed moist desquamation. The median time to onset of moist desquamation was 6 (4–7) weeks from start of RT. The sites of moist desquamation were most frequently occurred in anterior axillary

  4. Cellular cardiomyoplasty for a patient with heart failure

    International Nuclear Information System (INIS)

    Zhang Fumin; Chen Yijiang; Yang Zhijian; Gao Xiang; Ma Wenzhu; Li Chuanfu; Kao, Race L.

    2003-01-01

    Background: A 73-year-old man with a history of myocardial infarction and hypertension for 5 years suffered heart failure (NYHA III-IV). Methods: 2D echo indicated hypokinesia at septal, left ventricular anterior wall and apical regions. Coronary angiograms demonstrated 60% stenosis in distal left main and 99% stenosis in proximal and distal left anterior descending coronary arteries (LAD). Both proximal artery and middle left circumflex coronary artery (LC) had 90% stenosis, and diffuse stenosis of right coronary artery (RC) was found. Myocardial perfusion imaging using 99m Tc-MIBI indicated defective perfusion of left ventricular apex, anterior wall and septal region and severe reduced perfusion of posterior inferior wall. Myocardial metabolic activities ( 18 F-deoxyglucose) also showed comparable reductions. After exposing the heart, LAD, LC, and RC were all completely occluded and bypass procedure could not be completed. Autologous satellite cells were implanted without any complication and the patient had an uneventful recovery. Results: During the first 2 months, he remained in heart failure, and by the third month, he gradually improved and reached NYHA II. At fifth month after the procedure, significant increased ejection fraction (37.1-48.6%) and wall movement with modest reduction of left ventricular systolic diameter (48-45 mm) were observed. Imaging with 18 F-deoxyglucose showed dramatic improvement in myocardial metabolic activity with similar improvement in myocardial perfusion ( 99m Tc-MIBI). Conclusion: This is the first successful case of cellular cardiomyoplasty without any conjunctional procedure for patient with severe coronary heart disease and heart failure

  5. Place Atrium to Water Seal (PAWS): Assessing Wall Suction Versus No Suction for Chest Tubes After Open Heart Surgery.

    Science.gov (United States)

    Kruse, Tamara; Wahl, Sharon; Guthrie, Patricia Finch; Sendelbach, Sue

    2017-08-01

    Traditionally chest tubes are set to -20 cm H 2 O wall suctioning until removal to facilitate drainage of blood, fluid, and air from the pleural or mediastinal space in patients after open heart surgery. However, no clear evidence supports using wall suction in these patients. Some studies in patients after pulmonary surgery indicate that using chest tubes with a water seal is safer, because this practice decreases duration of chest tube placement and eliminates air leaks. To show that changing chest tubes to a water seal after 12 hours of wall suction (intervention) is a safe alternative to using chest tubes with wall suction until removal of the tubes (usual care) in patients after open heart surgery. A before-and-after quality improvement design was used to evaluate the differences between the 2 chest tube management approaches in chest tube complications, output, and duration of placement. A total of 48 patients received the intervention; 52 received usual care. The 2 groups (intervention vs usual care) did not differ significantly in complications (0 vs 2 events; P = .23), chest tube output (H 1 = 0.001, P = .97), or duration of placement (median, 47 hours for both groups). Changing chest tubes from wall suction to water seal after 12 hours of wall suction is a safe alternative to using wall suctioning until removal of the tubes. ©2017 American Association of Critical-Care Nurses.

  6. Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR

    Science.gov (United States)

    Lee, Lik Chuan; Zhihong, Zhang; Hinson, Andrew; Guccione, Julius M.

    2013-01-01

    Injection of Algisyl-LVR, a treatment under clinical development, is intended to treat patients with dilated cardiomyopathy. This treatment was recently used for the first time in patients who had symptomatic heart failure. In all patients, cardiac function of the left ventricle (LV) improved significantly, as manifested by consistent reduction of the LV volume and wall stress. Here we describe this novel treatment procedure and the methods used to quantify its effects on LV wall stress and function. Algisyl-LVR is a biopolymer gel consisting of Na+-Alginate and Ca2+-Alginate. The treatment procedure was carried out by mixing these two components and then combining them into one syringe for intramyocardial injections. This mixture was injected at 10 to 19 locations mid-way between the base and apex of the LV free wall in patients. Magnetic resonance imaging (MRI), together with mathematical modeling, was used to quantify the effects of this treatment in patients before treatment and at various time points during recovery. The epicardial and endocardial surfaces were first digitized from the MR images to reconstruct the LV geometry at end-systole and at end-diastole. Left ventricular cavity volumes were then measured from these reconstructed surfaces. Mathematical models of the LV were created from these MRI-reconstructed surfaces to calculate regional myofiber stress. Each LV model was constructed so that 1) it deforms according to a previously validated stress-strain relationship of the myocardium, and 2) the predicted LV cavity volume from these models matches the corresponding MRI-measured volume at end-diastole and end-systole. Diastolic filling was simulated by loading the LV endocardial surface with a prescribed end-diastolic pressure. Systolic contraction was simulated by concurrently loading the endocardial surface with a prescribed end-systolic pressure and adding active contraction in the myofiber direction. Regional myofiber stress at end-diastole and

  7. Global, Regional, and National Burden of Rheumatic Heart Disease, 1990-2015.

    Science.gov (United States)

    Watkins, David A; Johnson, Catherine O; Colquhoun, Samantha M; Karthikeyan, Ganesan; Beaton, Andrea; Bukhman, Gene; Forouzanfar, Mohammed H; Longenecker, Christopher T; Mayosi, Bongani M; Mensah, George A; Nascimento, Bruno R; Ribeiro, Antonio L P; Sable, Craig A; Steer, Andrew C; Naghavi, Mohsen; Mokdad, Ali H; Murray, Christopher J L; Vos, Theo; Carapetis, Jonathan R; Roth, Gregory A

    2017-08-24

    Rheumatic heart disease remains an important preventable cause of cardiovascular death and disability, particularly in low-income and middle-income countries. We estimated global, regional, and national trends in the prevalence of and mortality due to rheumatic heart disease as part of the 2015 Global Burden of Disease study. We systematically reviewed data on fatal and nonfatal rheumatic heart disease for the period from 1990 through 2015. Two Global Burden of Disease analytic tools, the Cause of Death Ensemble model and DisMod-MR 2.1, were used to produce estimates of mortality and prevalence, including estimates of uncertainty. We estimated that there were 319,400 (95% uncertainty interval, 297,300 to 337,300) deaths due to rheumatic heart disease in 2015. Global age-standardized mortality due to rheumatic heart disease decreased by 47.8% (95% uncertainty interval, 44.7 to 50.9) from 1990 to 2015, but large differences were observed across regions. In 2015, the highest age-standardized mortality due to and prevalence of rheumatic heart disease were observed in Oceania, South Asia, and central sub-Saharan Africa. We estimated that in 2015 there were 33.4 million (95% uncertainty interval, 29.7 million to 43.1 million) cases of rheumatic heart disease and 10.5 million (95% uncertainty interval, 9.6 million to 11.5 million) disability-adjusted life-years due to rheumatic heart disease globally. We estimated the global disease prevalence of and mortality due to rheumatic heart disease over a 25-year period. The health-related burden of rheumatic heart disease has declined worldwide, but high rates of disease persist in some of the poorest regions in the world. (Funded by the Bill and Melinda Gates Foundation and the Medtronic Foundation.).

  8. Regional interaction between myocardial sympathetic denervation, contractile dysfunction, and fibrosis in heart failure with preserved ejection fraction: {sup 11}C-hydroxyephedrine PET study

    Energy Technology Data Exchange (ETDEWEB)

    Aikawa, Tadao; Naya, Masanao; Obara, Masahiko [Hokkaido University, Department of Cardiovascular Medicine, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Oyama-Manabe, Noriko [Hokkaido University Hospital, Department of Diagnostic and Interventional Radiology, Sapporo (Japan); Manabe, Osamu [Hokkaido University, Department of Nuclear Medicine, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Magota, Keiichi [Hokkaido University Hospital, Division of Medical Imaging and Technology, Sapporo (Japan); Ito, Yoichi M. [Hokkaido University, Department of Biostatistics, Faculty of Medicine and Graduate School of Medicine, Sapporo (Japan); Katoh, Chietsugu [Hokkaido University, Department of Biomedical Science and Engineering, Faculty of Health Sciences, Sapporo (Japan); Tamaki, Nagara [Kyoto Prefectural University of Medicine, Department of Radiology, Kyoto (Japan)

    2017-10-15

    This investigation aimed to identify significant predictors of regional sympathetic denervation quantified by {sup 11}C-hydroxyephedrine (HED) positron emission tomography (PET) in patients with heart failure with preserved left ventricular ejection fraction (HFpEF). Included in the study were 34 patients (age 63 ± 15 years, 23 men) with HFpEF (left ventricular ejection fraction ≥40%) and 11 age-matched volunteers without heart failure. Cardiac magnetic resonance imaging was performed to measure left ventricular size and function, and the extent of myocardial late gadolinium enhancement (LGE). {sup 11}C-HED PET was performed to quantify myocardial sympathetic innervation that was expressed as a {sup 11}C-HED retention index (RI, %/min). To identify predictors of regional {sup 11}C-HED RI in HFpEF patients, we propose a multivariate mixed-effects model for repeated measures over segments with an unstructured covariance matrix. Global {sup 11}C-HED RI was significantly lower and more heterogeneous in HFpEF patients than in volunteers (P < 0.01 for all). Regional {sup 11}C-HED RI was correlated positively with systolic wall thickening (r = 0.42, P < 0.001) and negatively with the extent of LGE (r = -0.43, P < 0.001). Segments in HFpEF patients with a large extent of LGE had the lowest regional {sup 11}C-HED RI among all segments (P < 0.001 in post hoc tests). Multivariate analysis demonstrated that systolic wall thickening and the extent of LGE were significant predictors of regional {sup 11}C-HED RI in HFpEF patients (both P ≤ 0.001). Regional sympathetic denervation was associated with contractile dysfunction and fibrotic burden in HFpEF patients, suggesting that regional sympathetic denervation may provide an integrated measure of myocardial damage in HFpEF. (orig.)

  9. Diagnostic value of electrocardiography, dynamic isotope studies and angiography in coronary heart disease

    International Nuclear Information System (INIS)

    Haas, J.

    1986-01-01

    The goal of this work is on the basis of the case histories of 36 patients with heart anamneses (27 with electrocardiographically and/or enzymatically detected heart infarcts, 9 with various cardial diseases) to test the diagnostic value of stress electrocardiograms, dynamic isotope examinations of the heart and coronary angiographies in the cases of myocardial infarcts, heart wall aneurysms, coronary heart disease and in the determination of the global discharge fraction, specifically broad scanning (heart front, side and back walls) as well as fine scanning (individual coronary vessel branches). In the case of myocardial infarct the stress EKG and the heart scintigraphy agree with one another to a large degree, whereby scintigraphy (with 99mTc-DPTA) in addition detects infarcted myocardial regions. In the diagnosis of heart wall aneurysms scintigraphy and ventriculography had the same results in 91.6% of the cases. Coronary heart disease results agreed for all three methods in 91.7% of the cases and with scintigraphy and angiography in 94.4%. The degree of agreement between scintigraphy and coronary angiography is confirmed in the literature. One-, two- and 3-vessel diseases can be determined with these two methods in 90 to 75% agreement. The result lies thereby above the values of 201Tl-myocardial scintigraphy given in the literature. Also the global discharge fraction shows scintigraphic as well as angiographic agreement of almost 90%. (TRV) [de

  10. Pulmonary Vein, Dorsal Atrial Wall and Atrial Septum Abnormalities in Podoplanin Knockout Mice With Disturbed Posterior Heart Field Contribution

    NARCIS (Netherlands)

    Douglas, Yvonne L.; Mahtab, Edris A. F.; Jongbloed, Monique R. M.; Uhrin, Pavel; Zaujec, Jan; Binder, Bernd R.; Schalij, Martin J.; Poelmann, Robert E.; Deruiter, Marco C.; Gittenberger-De Groot, Adriana C.

    The developing sinus venosus myocardium, derived from the posterior heart field, contributes to the atrial septum, the posterior atrial wall, the sino-atrial node, and myocardium lining the pulmonary and cardinal veins, all expressing podoplanin, a coelomic and myocardial marker. . We compared

  11. Radionuclide cinematography of the heart

    International Nuclear Information System (INIS)

    Adam, W.E.; Sigel, H.; Geffers, H.; Bitter, F.; Meyer, G.; Kampmann, H.; Stauch, M.

    1976-01-01

    Radionuclide cinematography is described as a procedure making use of radiation-level variations above the heart after equipartitioning of sup(99m)Tc-labelled human serum albumin in the blood pool. Regional ventricular and vestibular variations are phase-shifted. This procedure permits delineation of aneurysmas with interphasic course, cicatrization of the cardiac wall not producing any cyclical variation. The study included normal subjects and 16 patients with full course infarction. Characteristic disturbances of motility distribution were found in all cases of scarred or aneurysmic alterations in the frontal and side walls of the left ventricle. The procedure was unable to detect two small infarction scars on the rear wall. The possibility of using radionuclide cinematography to prove coronary insufficiency as well as a comparison with other methods are discussed

  12. Neuronal mapping of the heart with 6-[18F]fluorometaraminol

    International Nuclear Information System (INIS)

    Wieland, D.M.; Rosenspire, K.C.; Hutchins, G.D.; Van Dort, M.; Rothley, J.M.; Mislankar, S.G.; Lee, H.T.; Massin, C.C.; Gildersleeve, D.L.; Sherman, P.S.

    1990-01-01

    The false neurotransmitter metaraminol labeled with fluorine-18 has been used to noninvasively assess regional adrenergic nerve density in the canine heart. Intravenous administration of 6-[ 18 F]fluorometaraminol (FMR) results in high, selective accumulation of radioactivity in the heart; drug blocking studies with desipramine and reserpine confirm the neuronal locus of FMR. Iodine-125 labeled metaraminol, however, shows no selective accumulation in the canine heart. Positron emission tomography (PET) analyses with FMR of closed-chest dogs bearing left ventricular neuronal defects clearly delineate the region of neuronal impairment; blood perfusion in the left ventricle wall was homogeneous as determined by [13N]NH3 tomograms. The accumulation of FMR in regionally denervated dog heart correlates closely (r = 0.88) with endogenous norepinephrine concentrations. PET-generated 18F time-activity curves demonstrate marked kinetic differences between normal and denervated myocardium. FMR/PET analysis could be used to assess the heterogeneity of sympathetic innervation in human heart disease contingent on the development of FMR with sufficiently high specific activity to clearly avoid pressor activity

  13. A method to quantitate regional wall motion in left ventriculography using Hildreth algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Mikio [Hyogo Red Cross Blood Center (Japan); Naito, Hiroaki; Sato, Yoshinobu; Tamura, Shinichi; Kurosawa, Tsutomu

    1998-06-01

    Quantitative measurement of ventricular wall motion is indispensable for objective evaluation of cardiac function associated with coronary artery disease. We have modified the Hildreth`s algorithm to estimate excursions of the ventricular wall on left ventricular images yielded by various imaging techniques. Tagging cine-MRI was carried out on 7 healthy volunteers. The original Hildreth method, the modified Hildreth method and the centerline method were applied to the outlines of the images obtained, to estimate excursion of the left ventricular wall and regional shortening and to evaluate the accuracy of these methods when measuring these parameters, compared to the values of these parameters measured actually using the attached tags. The accuracy of the original Hildreth method was comparable to that of the centerline method, while the modified Hildreth method was significantly more accurate than the centerline method (P<0.05). Regional shortening as estimated using the modified Hildreth method differed less from the actually measured regional shortening than did the shortening estimated using the centerline method (P<0.05). The modified Hildreth method allowed reasonable estimation of left ventricular wall excursion in all cases where it was applied. These results indicate that when applied to left ventriculograms for ventricular wall motion analysis, the modified Hildreth method is more useful than the original Hildreth method. (author)

  14. Scintigraphic detection of regional disruption of adrenergic neurons in the heart

    International Nuclear Information System (INIS)

    Sisson, J.C.; Lynch, J.J.; Johnson, J.; Jaques, S. Jr.; Wu, D.; Bolgos, G.; Lucchesi, B.R.; Wieland, D.M.

    1988-01-01

    Experiments were designed to detect regional disruptions of adrenergic neurons in the hearts of living dogs. The neuron disruption was achieved by the application of phenol to the epicardium of the left ventricle. Evidence for denervation was the reduction in endogenous norepinephrine (NE) concentrations in the myocardium beneath the region of phenol treatment and toward the apex. Radiolabeled meta-iodobenzylguanidine (MIBG) acts as an analog of NE and as such is concentrated in adrenergic nerve terminals. Following phenol application, MIBG labeled with 125 I was found, 20 hours after injection, to be distributed within myocardium in patterns comparable to those of NE. However, left stellectomy did not alter the distributions of NE or 125 I-MIBG in the myocardium and apparently did not disrupt adrenergic innervation. MIBG labeled with 123 I enabled scintigraphic images of heart neurons in the living dog 3 and 20 hours after injection; these images portrayed the regions of adrenergic neuron disruption caused by phenol treatment. Concentrations of thallium-201 depicted on scintigraphic image and of triphenyltetrazolium observed on in vitro staining demonstrated no myocardial injury. Thus, scintigraphy with 123 I-MIBG will display regional adrenergic denervations in the heart

  15. Numerical Simulation of Flow Features and Energy Exchange Physics in Near-Wall Region with Fluid-Structure Interaction

    Science.gov (United States)

    Zhang, Lixiang; Wang, Wenquan; Guo, Yakun

    Large eddy simulation is used to explore flow features and energy exchange physics between turbulent flow and structure vibration in the near-wall region with fluid-structure interaction (FSI). The statistical turbulence characteristics in the near-wall region of a vibrating wall, such as the skin frictional coefficient, velocity, pressure, vortices, and the coherent structures have been studied for an aerofoil blade passage of a true three-dimensional hydroturbine. The results show that (i) FSI greatly strengthens the turbulence in the inner region of y+ < 25; and (ii) the energy exchange mechanism between the flow and the vibration depends strongly on the vibration-induced vorticity in the inner region. The structural vibration provokes a frequent action between the low- and high-speed streaks to balance the energy deficit caused by the vibration. The velocity profile in the inner layer near the vibrating wall has a significant distinctness, and the viscosity effect of the fluid in the inner region decreases due to the vibration. The flow features in the inner layer are altered by a suitable wall vibration.

  16. Thinner regions of intracranial aneurysm wall correlate with regions of higher wall shear stress: a 7.0 tesla MRI

    Science.gov (United States)

    Blankena, Roos; Kleinloog, Rachel; Verweij, Bon H.; van Ooij, Pim; ten Haken, Bennie; Luijten, Peter R.; Rinkel, Gabriel J.E.; Zwanenburg, Jaco J.M.

    2016-01-01

    Purpose To develop a method for semi-quantitative wall thickness assessment on in vivo 7.0 tesla (7T) MRI images of intracranial aneurysms for studying the relation between apparent aneurysm wall thickness and wall shear stress. Materials and Methods Wall thickness was analyzed in 11 unruptured aneurysms in 9 patients, who underwent 7T MRI with a TSE based vessel wall sequence (0.8 mm isotropic resolution). A custom analysis program determined the in vivo aneurysm wall intensities, which were normalized to signal of nearby brain tissue and were used as measure for apparent wall thickness (AWT). Spatial wall thickness variation was determined as the interquartile range in AWT (the middle 50% of the AWT range). Wall shear stress was determined using phase contrast MRI (0.5 mm isotropic resolution). We performed visual and statistical comparisons (Pearson’s correlation) to study the relation between wall thickness and wall shear stress. Results 3D colored AWT maps of the aneurysms showed spatial AWT variation, which ranged from 0.07 to 0.53, with a mean variation of 0.22 (a variation of 1.0 roughly means a wall thickness variation of one voxel (0.8mm)). In all aneurysms, AWT was inversely related to WSS (mean correlation coefficient −0.35, P<0.05). Conclusions A method was developed to measure the wall thickness semi-quantitatively, using 7T MRI. An inverse correlation between wall shear stress and AWT was determined. In future studies, this non-invasive method can be used to assess spatial wall thickness variation in relation to pathophysiologic processes such as aneurysm growth and –rupture. PMID:26892986

  17. Mechanical analysis of congestive heart failure caused by bundle branch block based on an electromechanical canine heart model

    Energy Technology Data Exchange (ETDEWEB)

    Dou Jianhong; Xia Ling; Zhang Yu; Shou Guofa [Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027 (China); Wei Qing; Liu Feng; Crozier, Stuart [School of Information Technology and Electrical Engineering, University of Queensland, St Lucia, Brisbane, Queensland 4072 (Australia)], E-mail: xialing@zju.edu.cn

    2009-01-21

    Asynchronous electrical activation, induced by bundle branch block (BBB), can cause reduced ventricular function. However, the effects of BBB on the mechanical function of heart are difficult to assess experimentally. Many heart models have been developed to investigate cardiac properties during BBB but have mainly focused on the electrophysiological properties. To date, the mechanical function of BBB has not been well investigated. Based on a three-dimensional electromechanical canine heart model, the mechanical properties of complete left and right bundle branch block (LBBB and RBBB) were simulated. The anatomical model as well as the fiber orientations of a dog heart was reconstructed from magnetic resonance imaging (MRI) and diffusion tensor MRI (DT-MRI). Using the solutions of reaction-diffusion equations and with a strategy of parallel computation, the asynchronous excitation propagation and intraventricular conduction in BBB was simulated. The mechanics of myocardial tissues were computed with time-, sarcomere length-dependent uniaxial active stress initiated at the time of depolarization. The quantification of mechanical intra- and interventricular asynchrony of BBB was then investigated using the finite-element method with an eight-node isoparametric element. The simulation results show that (1) there exists inter- and intraventricular systolic dyssynchrony during BBB; (2) RBBB may have more mechanical synchrony and better systolic function of the left ventricle (LV) than LBBB; (3) the ventricles always move toward the early-activated ventricle; and (4) the septum experiences higher stress than left and right ventricular free walls in BBB. The simulation results validate clinical and experimental recordings of heart deformation and provide regional quantitative estimates of ventricular wall strain and stress. The present work suggests that an electromechanical heart model, incorporating real geometry and fiber orientations, may be helpful for better

  18. Value of gated SPECT in the analysis of regional wall motion of the interventricular septum after coronary artery bypass grafting

    International Nuclear Information System (INIS)

    Giubbini, Raffaele; Rossini, Pierluigi; Bertagna, Francesco; Bosio, Giovanni; Paghera, Barbara; Pizzocaro, Claudio; Canclini, Silvana; Terzi, Arturo; Germano, Guido

    2004-01-01

    The aim of this study was the evaluation of septal wall motion, perfusion and wall thickening after CABG in two groups of consecutive patients, one with grafted left anterior coronary artery and no history of myocardial infarction, and the other with previous anteroseptal myocardial infarction and impaired septal motion before surgery. The issue addressed was the ability of gated SPECT to differentiate between true paradoxical septal motion, characterised by paradoxical wall motion, depressed ejection fraction (EF), poor viability and compromised wall thickening, and pseudo-paradoxical motion, characterised by abnormal wall motion and regional EF but preserved perfusion and wall thickening. One hundred and thirty-two patients with previous anterior myocardial infarction, 82 patients with left anterior descending coronary disease and no history of myocardial infarction and 27 normal subjects underwent rest gated SPECT after 99m Tc-sestamibi injection, according to the standard QGS protocol. Quantitative regional EF, regional perfusion, regional wall motion and regional wall thickening were determined using a 20-segment model. Despite the presence of similar regional wall motion impairment in patients with and patients without septal infarction, in terms of regional EF (2.5%±3% vs 1.9%±4.9% p=NS) and inward septal motion (3±4.9 mm vs 2.3±6.1 mm p=NS), significant differences were observed in both perfusion (74.7%±6.2% vs 63.3%±13%, p>0.0001) and regional wall thickening (17.2%±7.4% vs 12.6%±7.2%, p>0.0001). Gated SPECT with perfusion tracers can reliably differentiate pseudo-paradoxical from true paradoxical septal motion in patients with previous CABG, and it may be the method of choice for evaluating left ventricular performance in this patient population. (orig.)

  19. Value of gated SPECT in the analysis of regional wall motion of the interventricular septum after coronary artery bypass grafting.

    Science.gov (United States)

    Giubbini, Raffaele; Rossini, Pierluigi; Bertagna, Francesco; Bosio, Giovanni; Paghera, Barbara; Pizzocaro, Claudio; Canclini, Silvana; Terzi, Arturo; Germano, Guido

    2004-10-01

    The aim of this study was the evaluation of septal wall motion, perfusion and wall thickening after CABG in two groups of consecutive patients, one with grafted left anterior coronary artery and no history of myocardial infarction, and the other with previous anteroseptal myocardial infarction and impaired septal motion before surgery. The issue addressed was the ability of gated SPECT to differentiate between true paradoxical septal motion, characterised by paradoxical wall motion, depressed ejection fraction (EF), poor viability and compromised wall thickening, and pseudo-paradoxical motion, characterised by abnormal wall motion and regional EF but preserved perfusion and wall thickening. One hundred and thirty-two patients with previous anterior myocardial infarction, 82 patients with left anterior descending coronary disease and no history of myocardial infarction and 27 normal subjects underwent rest gated SPECT after 99mTc-sestamibi injection, according to the standard QGS protocol. Quantitative regional EF, regional perfusion, regional wall motion and regional wall thickening were determined using a 20-segment model. Despite the presence of similar regional wall motion impairment in patients with and patients without septal infarction, in terms of regional EF (2.5%+/-3% vs 1.9%+/-4.9% p=NS) and inward septal motion (3+/-4.9 mm vs 2.3+/-6.1 mm p=NS), significant differences were observed in both perfusion (74.7%+/-6.2% vs 63.3%+/-13%, p>0.0001) and regional wall thickening (17.2%+/-7.4% vs 12.6%+/-7.2%, p>0.0001). Gated SPECT with perfusion tracers can reliably differentiate pseudo-paradoxical from true paradoxical septal motion in patients with previous CABG, and it may be the method of choice for evaluating left ventricular performance in this patient population.

  20. Value of gated SPECT in the analysis of regional wall motion of the interventricular septum after coronary artery bypass grafting

    Energy Technology Data Exchange (ETDEWEB)

    Giubbini, Raffaele; Rossini, Pierluigi; Bertagna, Francesco; Bosio, Giovanni; Paghera, Barbara; Pizzocaro, Claudio; Canclini, Silvana; Terzi, Arturo [Spedali Civili di Brescia, Department of Nuclear Medicine, Brescia (Italy); Germano, Guido [Cedars-Sinai Medical Center, Artificial Intelligence Program, Department of Medicine, Los Angeles, CA (United States)

    2004-10-01

    The aim of this study was the evaluation of septal wall motion, perfusion and wall thickening after CABG in two groups of consecutive patients, one with grafted left anterior coronary artery and no history of myocardial infarction, and the other with previous anteroseptal myocardial infarction and impaired septal motion before surgery. The issue addressed was the ability of gated SPECT to differentiate between true paradoxical septal motion, characterised by paradoxical wall motion, depressed ejection fraction (EF), poor viability and compromised wall thickening, and pseudo-paradoxical motion, characterised by abnormal wall motion and regional EF but preserved perfusion and wall thickening. One hundred and thirty-two patients with previous anterior myocardial infarction, 82 patients with left anterior descending coronary disease and no history of myocardial infarction and 27 normal subjects underwent rest gated SPECT after {sup 99m}Tc-sestamibi injection, according to the standard QGS protocol. Quantitative regional EF, regional perfusion, regional wall motion and regional wall thickening were determined using a 20-segment model. Despite the presence of similar regional wall motion impairment in patients with and patients without septal infarction, in terms of regional EF (2.5%{+-}3% vs 1.9%{+-}4.9% p=NS) and inward septal motion (3{+-}4.9 mm vs 2.3{+-}6.1 mm p=NS), significant differences were observed in both perfusion (74.7%{+-}6.2% vs 63.3%{+-}13%, p>0.0001) and regional wall thickening (17.2%{+-}7.4% vs 12.6%{+-}7.2%, p>0.0001). Gated SPECT with perfusion tracers can reliably differentiate pseudo-paradoxical from true paradoxical septal motion in patients with previous CABG, and it may be the method of choice for evaluating left ventricular performance in this patient population. (orig.)

  1. Prevalence and histopathological finding of thin-walled and thick-walled Sarcocysts in slaughtered cattle of Karaj abattoir, Iran.

    Science.gov (United States)

    Nourollahi-Fard, Saeid R; Kheirandish, Reza; Sattari, Saeid

    2015-06-01

    Sarcocystosis is a zoonotic disease caused by Sarcocystis spp. with obligatory two host life cycle generally alternating between an herbivorous intermediate host and a carnivorous definitive host. Some species of this coccidian parasite can cause considerable morbidity and mortality in cattle. The present study was set to investigate the prevalence of Sarcocystis spp. and type of cyst wall in slaughtered cattle of Karaj abattoir, Iran. For this purpose 125 cattle (88 males and 37 females) were investigated for the presence of macroscopic and microscopic Sarcocystis cysts in muscular tissues. No macroscopic Sarcocystis cysts were found in any of the samples. In light microscopy, 121 out of 125 cattle (96.8 %) had thin-walled cysts of Sarcocystis cruzi, while 43 out of them (34.4 %) had thick-walled Sarcocystis cyst. In this survey, the most infected tissue was esophagus and heart and the less was diaphragm. Thin-walled cysts (S. cruzi) mostly found in heart and skeletal muscle showed the less. However, thick-walled cyst (S. hominis or S. hirsuta) mostly were detected in diaphragm, heart muscle showed no thick-walled cyst. No significant relation was observed between age and sex and the rate of infection. The results showed that Sarcocystis cyst is prevalent in cattle in the North part of Iran and the evaluation of infection potential can be useful when considering control programs.

  2. Transmural expression of ion channels and transporters in human nondiseased and end-stage failing hearts

    DEFF Research Database (Denmark)

    Soltysinska, Ewa; Olesen, Søren-Peter; Christ, Torsten

    2009-01-01

    The cardiac action potential is primarily shaped by the orchestrated function of several different types of ion channels and transporters. One of the regional differences believed to play a major role in the progression and stability of the action potential is the transmural gradient of electrica...... cardiac ion channels and transporters which may in part explain the increased susceptibility to arrhythmia in end-state failing hearts....... activity across the ventricular wall. An altered balance in the ionic currents across the free wall is assumed to be a substrate for arrhythmia. A large fraction of patients with heart failure experience ventricular arrhythmia. However, the underlying substrate of these functional changes is not well......-established as expression analyses of human heart failure (HF) are sparse. We have investigated steady-state RNA levels by quantitative polymerase chain reaction of ion channels, transporters, connexin 43, and miR-1 in 11 end-stage HF and seven nonfailing (NF) hearts. The quantifications were performed on endo-, mid...

  3. Wall-based identification of coherent structures in wall-bounded turbulence

    Science.gov (United States)

    Sanmiguel Vila, C.; Flores, O.

    2018-04-01

    During the last decades, a number of reduced order models based on coherent structures have been proposed to describe wall-bounded turbulence. Many of these models emphasize the importance of coherent wall-normal velocity eddies (ν-eddies), which drive the generation of the very long streamwise velocity structures observed in the logarithmic and outer region. In order to use these models to improve our ability to control wall-bounded turbulence in realistic applications, these ν-eddies need to be identified from the wall in a non-intrusive way. In this paper, the possibility of using the pressure signal at the wall to identify these ν-eddies is explored, analyzing the cross-correlation between the wall-normal velocity component and the pressure fluctuations at the wall in a DNS of a turbulent channel flow at Reτ = 939. The results show that the cross-correlation has a region of negative correlation upstream, and a region of positive correlation backwards. In the spanwise direction the correlation decays monotonously, except very close to the wall where a change of sign of the correlation coefficient is observed. Moreover, filtering the pressure fluctuations at the wall in space results in an increase of the region where the cross-correlation is strong, both for the positively and the negatively correlated regions. The use of a time filter for the pressure fluctuations at the wall yields different results, displacing the regions of strong correlation without changing much their sizes. The results suggest that space-filtering the pressure at the wall is a feasible way to identify ν-eddies of different sizes, which could be used to trigger turbulent control strategies.

  4. Multi-region approach to free-boundary three-dimensional tokamak equilibria and resistive wall instabilities

    Science.gov (United States)

    Ferraro, N. M.; Jardin, S. C.; Lao, L. L.; Shephard, M. S.; Zhang, F.

    2016-05-01

    Free-boundary 3D tokamak equilibria and resistive wall instabilities are calculated using a new resistive wall model in the two-fluid M3D-C1 code. In this model, the resistive wall and surrounding vacuum region are included within the computational domain. This implementation contrasts with the method typically used in fluid codes in which the resistive wall is treated as a boundary condition on the computational domain boundary and has the advantage of maintaining purely local coupling of mesh elements. This new capability is used to simulate perturbed, free-boundary non-axisymmetric equilibria; the linear evolution of resistive wall modes; and the linear and nonlinear evolution of axisymmetric vertical displacement events (VDEs). Calculated growth rates for a resistive wall mode with arbitrary wall thickness are shown to agree well with the analytic theory. Equilibrium and VDE calculations are performed in diverted tokamak geometry, at physically realistic values of dissipation, and with resistive walls of finite width. Simulations of a VDE disruption extend into the current-quench phase, in which the plasma becomes limited by the first wall, and strong currents are observed to flow in the wall, in the SOL, and from the plasma to the wall.

  5. Multi-region approach to free-boundary three-dimensional tokamak equilibria and resistive wall instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Ferraro, N. M., E-mail: nferraro@pppl.gov; Lao, L. L. [General Atomics, La Jolla, California 92186 (United States); Jardin, S. C. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Shephard, M. S.; Zhang, F. [Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2016-05-15

    Free-boundary 3D tokamak equilibria and resistive wall instabilities are calculated using a new resistive wall model in the two-fluid M3D-C1 code. In this model, the resistive wall and surrounding vacuum region are included within the computational domain. This implementation contrasts with the method typically used in fluid codes in which the resistive wall is treated as a boundary condition on the computational domain boundary and has the advantage of maintaining purely local coupling of mesh elements. This new capability is used to simulate perturbed, free-boundary non-axisymmetric equilibria; the linear evolution of resistive wall modes; and the linear and nonlinear evolution of axisymmetric vertical displacement events (VDEs). Calculated growth rates for a resistive wall mode with arbitrary wall thickness are shown to agree well with the analytic theory. Equilibrium and VDE calculations are performed in diverted tokamak geometry, at physically realistic values of dissipation, and with resistive walls of finite width. Simulations of a VDE disruption extend into the current-quench phase, in which the plasma becomes limited by the first wall, and strong currents are observed to flow in the wall, in the SOL, and from the plasma to the wall.

  6. Evaluation of right ventricular regional wall motion in inferior myocardial infarction by cine MRI

    International Nuclear Information System (INIS)

    Nishino, Masami; Ohnishi, Shusaku; Hasegawa, Shinji

    1991-01-01

    The purpose of this study is to evaluate right ventricular regional wall motion in inferior myocardial infarction by cine MRI. Thirteen patients with inferior myocardial infarction were investigated by cine MRI and were divided into proximal group which consisted of seven patients: >90% stenosis in segment 1 or 2 of right coronary artery and distal group which consisted of six patients: >90% stenosis in segment 3 or 4 of right coronary artery. Cine MRI was performed by 1.5 tesla magnet system (Signa, GE). To depict the regional asynergy, right ventricular wall was divided into 6 segments as follows: Segments 1 and 2 were upper and lower segments in transverse planes, respectively. Segments 3 and 4 were free wall and diaphragmatic segments of outflow tract, and segments 5 and 6 were of inflow tract in sagittal planes. Our results were as follows: (1) In proximal group, right ventricular asynergy was detected in six patients but in distal group it was detected in only one patient; (2) Right ventricular asynergy was detected most frequently at diaphragmatic segments in sagittal planes; (3) All the patients who had shown the hemodynamic deterioration of right ventricle on acute phase of inferior myocardial infarction presented the broad asynergy in right ventricle; (4) Cine MRI is clinically useful in evaluating right ventricular regional wall movement and diagnosing right ventricular infarction. (author)

  7. Region and cell-type resolved quantitative proteomic map of the human heart

    DEFF Research Database (Denmark)

    Doll, Sophia; Dreßen, Martina; Geyer, Philipp E

    2017-01-01

    The heart is a central human organ and its diseases are the leading cause of death worldwide, but an in-depth knowledge of the identity and quantity of its constituent proteins is still lacking. Here, we determine the healthy human heart proteome by measuring 16 anatomical regions and three major...... cardiac cell types by high-resolution mass spectrometry-based proteomics. From low microgram sample amounts, we quantify over 10,700 proteins in this high dynamic range tissue. We combine copy numbers per cell with protein organellar assignments to build a model of the heart proteome at the subcellular...

  8. CLINICAL AND ANGIOGRAPHIC PROFILE OF PATIENTS WITH COMPLETE HEART BLOCK

    Directory of Open Access Journals (Sweden)

    Kavya Pingali

    2017-05-01

    Full Text Available BACKGROUND The angiographic findings and prognosis of patients with Complete Heart Block (CHB remain unclear. Thus, we aimed to study the clinical profile, risk factors, angiographic distribution and in-hospital outcomes of patients with complete heart block. MATERIALS AND METHODS This was a prospective, single-centred study which included 100 patients who came to the emergency department with CHB. Routine blood investigations including serum electrolytes were done. Coronary angiogram was done and lesions were assessed. Temporary pacemaker was implanted followed by permanent pacemakers in required patients, and in-hospital complications were noted down. RESULTS Commonest age group was above 60 years (75%. The patients were predominantly males. Most common presentation was chest pain (60%; there was regional wall motion abnormality in 30% patients. Degenerative complete heart block was seen in 34% patients, diphtheric myocarditis in 15%, hypokalaemic in 15%, dilated cardiomyopathy in 2%. Of total 53 patients had AV block, 14 had bifascicular block, 23 had LBBB, 6 had RBBB, 3 had Mobitz I and 1 had Mobitz II. Inferior wall myocardial infarction (MI was pervasively present in patients. Temporary pacemakers were implanted in 6 patients and permanent pacemakers in 43 patients. In-hospital outcomes constituted of complication like cardiogenic shock (10% and death (26%. The patients who died either had 80% -90% stenosis in RCA, triple vessel disease, ostioproximal LAD occlusion or diphtheric myocarditis. CONCLUSION Complete heart block was majorly associated with advanced age and inferior wall MI, virtually caused by dominant RCA occlusion. The in-hospital mortality was significantly higher in the patients with CHB.

  9. The relationship between phase and heart rate

    International Nuclear Information System (INIS)

    Underwood, S.R.; Walton, S.; Brown, N.J.G.; Laming, P.J.; Ell, P.J.; Emanuel, R.W.; Swanton, R.H.

    1984-01-01

    The Fourier phase image is used in rest and stress radionuclide angiocardiography to assess the timing of ventricular wall motion in a regional fashion, and areas of high phase are taken to reprensent areas of delayed contraction. However, phase increases with heart rate and this can make interpretation difficult. This study investigates the relationship between phase and heart rate. A heterogenous group of 43 subjects was studied by ECG-gated equilibrium radionuclide angiocardiography, all of the subjects having normal extent of left ventricular wall motion as judged by normal ejection fraction and normal amplitude image. Mean left ventricular phase correlated well with mean time of end systole (r=0.92), but there was no correlation with time of end diastole.Thus phase reflects the time of end systole as a proportion of cycle length and should be linearly related to heart rate provided the duration of systole is unchanged. In 28 normal subjects mean left ventricular phase correlated linearly with resting rate (r=0.91), and when exercised the relationship was maintained up to 90 beats per minute. Above this rate the increases were less marked as the duration of systole shortened. The same was true in 4 subjects paced at different rates. Mean resting heart rate in the normal subjects was 70 beats per minute and correcting phase linearly to rate 70 did not change mean left ventricular phase but did decrease the standard deviation from 18 degree to 12 degree. It is concluded that correcting phase for heart rate below 90 beats per minute will increase the sensitivity of the phase image to abnormalities of the timing of ventricular contraction. This correction should be appropriate in resting, isometric exercise, and cold pressor studies but because of the higher heart rates involved will not be appropriate for bicycle exercise. (Author)

  10. Optical wall dynamics induced by coexistence of monostable and bistable spatial regions.

    Science.gov (United States)

    Odent, V; Louvergneaux, E; Clerc, M G; Andrade-Silva, I

    2016-11-01

    When nonequilibrium extended homogeneous systems exhibit multistability, it leads to the presence of domain walls between the existing equilibria. Depending on the stability of the steady states, the dynamics differs. Here, we consider the interface dynamics in the case of a spatially inhomogeneous system, namely, an optical system where the control parameter is spatially Gaussian. Then interfaces connect the monostable and the bistable nonuniform states that are associated with two distinct spatial regions. The coexistence of these two regions of different stability induces relaxation dynamics and the propagation of a wall with a time-dependent speed. We emphasize analytically these two dynamical behaviors using a generic bistable model. Experimentally, an inhomogeneous Gaussian light beam traveling through either a dye-doped liquid crystal cell or a Kerr cavity depicts these behaviors, in agreement with the theoretical predictions.

  11. Fast Simulation of Mechanical Heterogeneity in the Electrically Asynchronous Heart Using the MultiPatch Module.

    Directory of Open Access Journals (Sweden)

    John Walmsley

    2015-07-01

    Full Text Available Cardiac electrical asynchrony occurs as a result of cardiac pacing or conduction disorders such as left bundle-branch block (LBBB. Electrically asynchronous activation causes myocardial contraction heterogeneity that can be detrimental for cardiac function. Computational models provide a tool for understanding pathological consequences of dyssynchronous contraction. Simulations of mechanical dyssynchrony within the heart are typically performed using the finite element method, whose computational intensity may present an obstacle to clinical deployment of patient-specific models. We present an alternative based on the CircAdapt lumped-parameter model of the heart and circulatory system, called the MultiPatch module. Cardiac walls are subdivided into an arbitrary number of patches of homogeneous tissue. Tissue properties and activation time can differ between patches. All patches within a wall share a common wall tension and curvature. Consequently, spatial location within the wall is not required to calculate deformation in a patch. We test the hypothesis that activation time is more important than tissue location for determining mechanical deformation in asynchronous hearts. We perform simulations representing an experimental study of myocardial deformation induced by ventricular pacing, and a patient with LBBB and heart failure using endocardial recordings of electrical activation, wall volumes, and end-diastolic volumes. Direct comparison between simulated and experimental strain patterns shows both qualitative and quantitative agreement between model fibre strain and experimental circumferential strain in terms of shortening and rebound stretch during ejection. Local myofibre strain in the patient simulation shows qualitative agreement with circumferential strain patterns observed in the patient using tagged MRI. We conclude that the MultiPatch module produces realistic regional deformation patterns in the asynchronous heart and that

  12. Revision of orthovoltage chest wall treatment using Monte Carlo simulations.

    Science.gov (United States)

    Zeinali-Rafsanjani, B; Faghihi, R; Mosleh-Shirazi, M A; Mosalaei, A; Hadad, K

    2017-01-01

    Given the high local control rates observed in breast cancer patients undergoing chest wall irradiation by kilovoltage x-rays, we aimed to revisit this treatment modality by accurate calculation of dose distributions using Monte Carlo simulation. The machine components were simulated using the MCNPX code. This model was used to assess the dose distribution of chest wall kilovoltage treatment in different chest wall thicknesses and larger contour or fat patients in standard and mid sternum treatment plans. Assessments were performed at 50 and 100 cm focus surface distance (FSD) and different irradiation angles. In order to evaluate different plans, indices like homogeneity index, conformity index, the average dose of heart, lung, left anterior descending artery (LAD) and percentage target coverage (PTC) were used. Finally, the results were compared with the indices provided by electron therapy which is a more routine treatment of chest wall. These indices in a medium chest wall thickness in standard treatment plan at 50 cm FSD and 15 degrees tube angle was as follows: homogeneity index 2.57, conformity index 7.31, average target dose 27.43 Gy, average dose of heart, lung and LAD, 1.03, 2.08 and 1.60 Gy respectively and PTC 11.19%. Assessments revealed that dose homogeneity in planning target volume (PTV) and conformity between the high dose region and PTV was poor. To improve the treatment indices, the reference point was transferred from the chest wall skin surface to the center of PTV. The indices changed as follows: conformity index 7.31, average target dose 60.19 Gy, the average dose of heart, lung and LAD, 3.57, 6.38 and 5.05 Gy respectively and PTC 55.24%. Coverage index of electron therapy was 89% while it was 22.74% in the old orthovoltage method and also the average dose of the target was about 50 Gy but in the given method it was almost 30 Gy. The results of the treatment study show that the optimized standard and mid sternum treatment for different chest

  13. Evaluation of echogenicity of the heart in Kawasaki disease.

    Science.gov (United States)

    Nagata, Hazumu; Yamamura, Kenichiro; Uike, Kiyoshi; Nakashima, Yasutaka; Hirata, Yuichiro; Morihana, Eiji; Mizuno, Yumi; Ishikawa, Shiro; Hara, Toshiro

    2014-08-01

    Pathologic studies of the heart in patients with Kawasaki disease (KD) revealed vasculitis, valvulitis, myocarditis, and pericarditis. However, there have been no studies on the quantitative determination of multi-site echogenicity of the heart in KD patients. It is also undetermined whether the degree of echogenicity of each site of the heart in patients with KD might be related to the response to intravenous immunoglobulin (IVIG) treatment. In 81 KD patients and 30 control subjects, we prospectively analyzed echogenicity of the heart. Echogenicity was measured in four sites: coronary artery wall (CAW), mitral valve (MV), papillary muscle (PM), and ascending aortic wall (AAo wall) by the calibrated integrated backscatters (cIBs). The cIB values of all measurement sites at acute phase in KD patients were significantly higher than those in control subjects (KD patients vs control subjects; CAW, 19.8 ± 6.2 dB vs 14.5 ± 2.0 dB, p IVIG nonresponders were significantly higher than those in responders. Conclusion: Echogenicity of the heart in KD patients at the acute phase increased not only in the coronary artery wall but also in other parts of the heart. Echogenicity of CAW might be helpful in determining the unresponsiveness of IVIG treatment.

  14. Factors affecting regional pulmonary blood flow in chronic ischemic heart disease

    International Nuclear Information System (INIS)

    Pistolesi, M.; Miniati, M.; Bonsignore, M.

    1988-01-01

    To assess the effect of left heart disease on pulmonary blood flow distribution, we measured mean pulmonary arterial and wedge pressures, cardiac output, pulmonary vascular resistance, pulmonary blood volume, and arterial oxygen tension before and after treatment in 13 patients with longstanding ischemic heart failure and pulmonary edema. Pulmonary edema was evaluated by a radiographic score, and regional lung perfusion was quantified on a lung scan by the upper to lower third ratio (U:L ratio) of pulmonary blood flow per unit of lung volume. In all cases, redistribution of lung perfusion toward the apical regions was observed; this pattern was not affected by treatment. After treatment, pulmonary vascular pressures, resistance, and edema were reduced, while pulmonary blood volume did not change. At this time, pulmonary vascular resistance showed a positive correlation with the U:L ratio (r = 0.78; P less than 0.01), whereas no correlation was observed between U:L ratio and wedge pressure, pulmonary edema, or arterial oxygen tension. Hence, redistribution of pulmonary blood flow, in these patients, reflects chronic structural vascular changes prevailing in the dependent lung regions

  15. Determination of global heart function parameters

    International Nuclear Information System (INIS)

    Adam, W.E.; Hoffmann, H.; Sigel, H.; Bitter, F.; Nechwatal, W.; Stauch, M.; Ulm Univ.; Freiburg Univ.

    1980-01-01

    1. ECG-triggered scintigraphy of the interior of the heart (radioactive ventriculography) is a reliable non-invasive technique for the acquisition of the global and regional function of the left ventricle. 2. The most important global parameter is the output function (OF) of the left ventricle. It can be measured exactly. The decrease of the OF under load is typical for coronary insufficience under load, but is not specifically. 3. A movement disturbance on the ground of a KHK is recognized with highest sensitivity at the decrease of the maximum relaxation velocity of the global left-ventricular time-activity characteristic (fast phase of filling). 4. Regional wall movement disturbances can be measured quantitatively by means of viewing the radioactive nucleid ventriculogramm at the display. 5. The quantitative measurement of the regional function needs an extensive analysis of the local time-activity characteristics of a representative coronary cycle. For this the amplitude and phase and the contraction and relaxation velocity of all time-activity characteristics is determined by Fourier analysis and their spatial distribution is drawn (parametric scan). 6. The parametric scans (distribution of amplitude, phase, contraction and relaxation velocities) describe the regional wall movement in detail, the reliability of its quantitative acquisition has to be approved by further investigations. (orig.) [de

  16. AcvR1-mediated BMP signaling in second heart field is required for arterial pole development: implications for myocardial differentiation and regional identity.

    Science.gov (United States)

    Thomas, Penny S; Rajderkar, Sudha; Lane, Jamie; Mishina, Yuji; Kaartinen, Vesa

    2014-06-15

    BMP signaling plays an essential role in second heart field-derived heart and arterial trunk development, including myocardial differentiation, right ventricular growth, and interventricular, outflow tract and aortico-pulmonary septation. It is mediated by a number of different BMP ligands, and receptors, many of which are present simultaneously. The mechanisms by which they regulate morphogenetic events and degree of redundancy amongst them have still to be elucidated. We therefore assessed the role of BMP Type I receptor AcvR1 in anterior second heart field-derived cell development, and compared it with that of BmpR1a. By removing Acvr1 using the driver Mef2c[AHF]-Cre, we show that AcvR1 plays an essential role in arterial pole morphogenesis, identifying defects in outflow tract wall and cushion morphology that preceded a spectrum of septation defects from double outlet right ventricle to common arterial trunk in mutants. Its absence caused dysregulation in gene expression important for myocardial differentiation (Isl1, Fgf8) and regional identity (Tbx2, Tbx3, Tbx20, Tgfb2). Although these defects resemble to some degree those in the equivalent Bmpr1a mutant, a novel gene knock-in model in which Bmpr1a was expressed in the Acvr1 locus only partially restored septation in Acvr1 mutants. These data show that both BmpR1a and AcvR1 are needed for normal heart development, in which they play some non-redundant roles, and refine our understanding of the genetic and morphogenetic processes underlying Bmp-mediated heart development important in human congenital heart disease. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Evaluation of regional wall motion in myocardial infarction using animation ECG gated cardiac computed tomography

    International Nuclear Information System (INIS)

    Shimizu, Takahiko; Hyodo, Haruo; Hayashi, Terumi; Yamamoto, Hideo; Yagi, Shigeru

    1984-01-01

    Regional wall motion of the left ventricle was evaluated in 21 patients with myocardial infarction using an animation system of gated cardiac computed tomographic (CT) images (animation gated CCT). The results obtained were compared with data by two-dimensional echocardiography (2-DE). 1. Evaluation of the asynergic area by animation gated CCT and 2-DE: Animation gated CCT detected the following specific regions with asynergy established by 2-DE; 10/10 cases (100%) at the anterior wall of the left ventricle, 14/14 cases (100%) at the interventricular septum, and 9/11 cases (81.8%) at the infero-posterior wall. In addition, one false positive case and one negative case were observed at the lateral wall and the apex, respectively. Of 37 instances with asynergic areas established by 2-DE, 21 cases or 89.2% were detected by animation gated CCT; the sensitivity was 91.9%. 2. Evaluation of severity of asynergy by animation gated CCT and 2-DE: The degree of asynergy evaluated by both methods was compared with each other, and the agreement was as follows: 10/10 cases (100%) at the left-ventricular anterior wall, 13/13 cases (100%) at the interventricular septum, and 7/9 cases (77.8%) at the infero-posterior wall. 3. Evaluation of the asynergic area by nonanimation gated CCT and 2-DE: Nonanimation gated CCT detected asynergic areas ascertained by 2-DE at the following areas; 8/10 cases (80%) at the left-ventricular anterior wall, 12/14 cases (85.7%) at the interventricular septum, and 4/11 cases (36.4%) at the infero-posterior wall. The difference between animation and nonanimation gated CCT was statistically significant (p<0.05). The severity of asynergy could not be evaluated by nonanimation gated CCT. (J.P.N.)

  18. The plasma-wall interaction region: a key low temperature plasma for controlled fusion

    International Nuclear Information System (INIS)

    Counsell, G F

    2002-01-01

    The plasma-wall interaction region of a fusion device provides the interface between the hot core plasma and the material surfaces. To obtain acceptably low levels of erosion from these surfaces requires most of the power leaving the core to be radiated. This is accomplished in existing devices by encouraging plasma detachment, in which the hot plasma arriving in the region is cooled by volume recombination and ion-neutral momentum transfer with a dense population of neutrals recycled from the surface. The result is a low temperature (1 eV e e >10 19 m -3 ) but weakly ionized (n 0 >10 20 m -3 , n e /n 0 <0.1) plasma found nowhere else in the fusion environment. This plasma provides many of the conditions found in industrial plasmas exploiting plasma chemistry and the presence of carbon in the region (in the form of carbon-fibre composite used in the plasma facing materials) can result in the formation of deposited hydrocarbon films. The plasma-wall interaction region is therefore among the most difficult in fusion to model, requiring an understanding of atomic, molecular and surface physics issues

  19. Myocardial metabolism, perfusion, wall motion and electrical activity in Duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Perloff, J.K.; Henze, E.; Schelbert, H.R.

    1982-01-01

    The cardiomyopathy of Duchenne's muscular dystrophy originates in the posterobasal left ventricle and extends chiefly to the contiguous lateral wall. Ultrastructural abnormalities in these regions precede connective tissue replacement. We postulated that a metabolic fault coincided with or antedated the subcellular abnormality. Accordingly, regional left ventricular metabolism, perfusion and wall motion were studied using positron computed tomography and metabolic isotopes supplemented by thallium perfusion scans, equilibrium radionuclide angiography and M-mode and two-dimensional echocardiography. To complete the assessment, electrocardiograms, vectorcardiograms, 24 hour taped electrocardiograms and chest x-rays were analyzed. Positron computed tomography utilizing F-18 2-fluoro 2-deoxyglucose (FDG) provided the first conclusive evidence supporting the hypothesis of a premorphologic regional metabolic fault. Thus, cardiac involvement in duchenne dystrophy emerges as a unique form of heart disease, genetically targeting specific regions of ventricular myocardium for initial metabolic and subcellular changes. Reported ultrastructural abnormalities of the impulse and conduction systems provide, at least in part, a basis for the clinically observed sinus node, intraatrial, internodal, AV nodal and infranodal disorders

  20. Fourier analysis of heart SPECT slices: from remodelation to function?

    International Nuclear Information System (INIS)

    Zigman, M.; Prpic, H.; Lokner, V.

    1994-01-01

    The aim of this study was to determine character of the spatial distribution of marked erythrocytes in heart chambers, lungs and great blood vessels in relation to function of the left and right heart. Investigation included total of 142 subjects, 28 of which were without subjective and clinical signs of heart disease as well as 56 after myocardial infarction (30 of anterior localization, 26 of inferior infarction), 35 with predominant left heart disease (aortic valve disease, dilatative myocardiopathy, etc.) and 23 with predominant right heart disease (atrial septal defect, mitral valve disease). Radionuclide ventriculography (RNV) at rest, and thorax SPECT were performed in all subjects with 740 MBq Tc-99m after in vivo erythrocyte labelling with pyrophosphate. Ultrasound investigation was performed on all the subjects with heart disease and 87 of them underwent invasive cardiac investigation. RNV analysis revealed scintigraphic data on left and right ventricle: global ejection fraction (GEF), end-systolic volume (ESV), end-diastolic volume (EDV), fast tilling rate (FFR), fast emptying rate (FER) as well as regional wall motion shortening. Reconstruction of 64x64x8 SPECT images resulted in 3x64 slices (transversal, coronal and sagittal slices). Fourier analysis of 20-32 reconstructed slices in all three dimensions gave amplitude image of the intensity distribution of marked erythrocytes in heart chambers lungs and great blood vessels as well as phase display of spatial localization of regional amplitude values. Results of joint ROC curves constructed for detection, localization and character of heart disease in all subjects revealed significant clinical information content of SPECT data. Evaluation of RI retention using amplitude images in 3D provides insight in regional changes of volume, particular for atrial and lung involvement. (author)

  1. Boundary layer theory approach to the concentration layer adjacent to the ceiling wall of a hydrogen leakage: Axisymmetric impinging and far regions

    Energy Technology Data Exchange (ETDEWEB)

    El-Amin, M.F.; Kanayama, H. [Department of Mechanical Engineering, Faculty of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

    2009-02-15

    As hydrogen leaks into a partially open space with a ceiling wall, a boundary layer of hydrogen can be constructed under that wall due to the impingement on the wall and the buoyancy force. The resulting boundary layer can be divided into two regions, namely the stagnation-point region and the far region. When the geometry of the source of the hydrogen leak is circular, such as a pinhole or an o-ring, the behavior of leakage flow will be axisymmetric due to the resulting radial jet. In contrast, when the geometry of the source of the hydrogen leak is planar, such as a crack, the behavior of leakage flow will be planar due to the resulting planar jet. Previously, we studied the planar case in the context of both the stagnation-point flow region [El-Amin MF, Kanayama H. Boundary layer theory approach to the concentration layer adjacent to a ceiling wall at impinging region of a hydrogen leakage. Int J Hydrogen Energy 2008; 33(21): 6393-00] and the far region [El-Amin MF, Inoue M, Kanayama H. Boundary layer theory approach to the concentration layer adjacent to a ceiling wall of a hydrogen leakage: far region. Int J Hydrogen Energy 2008; 33(24):7642-7]. This paper is concerned with both the stagnation-point flow region and the far region of the axisymmetric concentration boundary layer adjacent to a ceiling wall. Flow in the stagnation-point region is treated as Hiemenz flow, while it is treated as Blasius flow in the far region. The current results are compared with the planar cases [El-Amin MF, Kanayama H. Boundary layer theory approach to the concentration layer adjacent to a ceiling wall at impinging region of a hydrogen leakage. Int J Hydrogen Energy 2008; 33(21): 6393-00; El-Amin MF, Inoue M, Kanayama H. Boundary layer theory approach to the concentration layer adjacent to a ceiling wall of a hydrogen leakage: far region. Int J Hydrogen Energy 2008; 33(24):7642-7] for both stagnation-point flow and far regions. Both momentum and concentration boundary layer

  2. Determination of optimum insulation thicknesses of the external walls and roof (ceiling) for Turkey's different degree-day regions

    International Nuclear Information System (INIS)

    Sisman, Nuri; Kahya, Emin; Aras, Nil; Aras, Haydar

    2007-01-01

    The external walls and roof of a building are the interface between its interior and the outdoor environment. Insulation of the external walls and roof is the most cost-effective way of controlling the outside elements to make homes more comfortable. Although insulation is generally accepted as a factor increasing the building costs, with the calculations we have shown that this is not the case. Fuel consumption and operational costs are reduced by increasing the thickness of the external walls and roof (ceiling), despite an increase in the investment costs. According to Turkish Standard Number 825 (TS 825), there are four different degree-day (DD) regions, and the required heat loads for the buildings in these regions exhibit large differences. Therefore, a method based on costs is needed for the determination of optimum insulation thicknesses of different DD regions. In this study, optimum insulation thicknesses for different DD regions of Turkey, namely, Izmir (DD: 1450), Bursa (DD: 2203), Eskisehir (DD: 3215) and Erzurum (DD: 4856), have been determined for a lifetime of N years, maximizing the present worth value of annual energy savings for insulated external walls

  3. Role of wall-attached structures in the interface of the quiescent core region in turbulent pipe flow

    Science.gov (United States)

    Yang, Jongmin; Hwang, Jinyul; Sung, Hyung Jin

    2017-11-01

    The effects of low- and high-speed structures on the interface of the quiescent core region are explored using direct numerical simulation data of turbulent pipe flow. The quiescent core region is a uniform momentum zone located at the center of the pipe flow, which contains the highest streamwise momentum with a low level of turbulence. The interface of the quiescent core region can be identified from the probability density function of the streamwise modal velocity. In the vicinity of the interface of the quiescent core region, the streamwise velocity changes abruptly. The abrupt jump in velocity causes an increase of the velocity gradient. The interface of the quiescent core region is similar to the laminar superlayer in turbulent/non-turbulent interface. The interface of the quiescent core region contains the low- and high-speed structures. They can be classified into wall-attached and detached structures depending on the distance between the structures and the wall. The influence of the detached structures accounted for most of the number of detected structures is negligible due to its small volume. Conversely, the wall-attached structures adjacent to the interface have a huge influence on the statistical amount of the interface, such as entrainment characteristics. This work was supported by the Creative Research Initiatives (No. 2017-013369) program of the National Research Foundation of Korea (MSIP).

  4. Connection forms for beating the heart

    DEFF Research Database (Denmark)

    Mensch, Arthur; Piuze, Emmanuel; Lehnert, Lucas

    2014-01-01

    We combine recent work on modeling cardiac mechanics using a finite volume method with the insight that heart wall myofiber orientations exhibit a particular volumetric geometry. In our finite vol- ume mechanical simulation we use Maurer-Cartan one-forms to add a geometrical consistency term...... to control the rate at which myofiber ori- entation changes in the direction perpendicular to the heart wall. This allows us to estimate material properties related to both the passive and active parameters in our model. We have obtained preliminary results on the 4 canine datasets of the 2014 mechanics...... challenge using the FEBio software suite. In ongoing work we are validating and improving the model using rat heart (ex-vivo DTI and in-vivo tagging) MRI datasets, from which we have estimated strain tensors....

  5. Moving frames for heart fiber geometry

    DEFF Research Database (Denmark)

    Piuze, Emmanuel; Sporring, Jon; Siddiqi, Kaleem

    2013-01-01

    fibers is central to our understanding of normal heart function. Motivated by a recent abstraction by Savadjiev et al. of heart wall fibers into generalized helicoid minimal surfaces, this paper develops an extension based on differential forms. The key idea is to use Maurer-Cartan’s method of moving...

  6. Small scale structure in the wall region of a turbulent boundary layer

    International Nuclear Information System (INIS)

    Bogar, T.J.

    1975-01-01

    This paper is a report of the construction and application of an extremely small hot-wire X-probe (typical dimensions of 100 μ) to the measurement of Reynolds stress in the wall region of the turbulent boundary layer of a flat plate at high Reynolds number (Re/sub theta/ = 11,300). In the present flow, the size of the probe corresponds to a dimensionless length based on wall parameters of lu/sub tau//ν = 3. Probe construction methods are described. The Wyngaard-Lumley constant temperature anemometer used to heat the wire is analyzed, and a direct acoustical frequency calibration of the wire is made. This calibration shows the small wire to have uniform frequency response to 15 kHz. A novel calibration technique is employed using a high speed, digital mini-computer to determine the velocity in the stream direction and in a direction normal to the wall by matching the unique voltage pairs produced by the X-wire array in a turbulent flow to the voltage pairs produced when the probe is exposed to a known uniform flow inclined at various angles

  7. Hypertensive heart disease versus hypertrophic cardiomyopathy: multi-parametric cardiovascular magnetic resonance discriminators when end-diastolic wall thickness ≥ 15 mm

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Jonathan C.L. [University Hospitals Bristol NHS Foundation Trust, NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute (United Kingdom); University of Bristol, School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences (United Kingdom); Rohan, Stephen [University of Bristol, Medical School, Faculty of Medicine and Dentistry (United Kingdom); Ghosh Dastidar, Amardeep; Harries, Iwan; Lawton, Christopher B. [University Hospitals Bristol NHS Foundation Trust, NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute (United Kingdom); Ratcliffe, Laura E.; Burchell, Amy E.; Nightingale, Angus K. [University Hospitals Bristol NHS Foundation Trust, CardioNomics Research Group, Clinical Research and Imaging Centre, Bristol Heart Institute (United Kingdom); Hart, Emma C.; Paton, Julian F.R. [University of Bristol, School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences (United Kingdom); University Hospitals Bristol NHS Foundation Trust, CardioNomics Research Group, Clinical Research and Imaging Centre, Bristol Heart Institute (United Kingdom); Hamilton, Mark C.K. [University Hospitals Bristol NHS Foundation Trust, Department of Radiology, Bristol Royal Infirmary (United Kingdom); Manghat, Nathan E. [University Hospitals Bristol NHS Foundation Trust, NIHR Bristol Cardiovascular Biomedical Research Unit, Cardiac Magnetic Resonance Department, Bristol Heart Institute (United Kingdom); University Hospitals Bristol NHS Foundation Trust, Department of Radiology, Bristol Royal Infirmary (United Kingdom)

    2017-03-15

    European guidelines state left ventricular (LV) end-diastolic wall thickness (EDWT) ≥15 mm suggests hypertrophic cardiomyopathy (HCM), but distinguishing from hypertensive heart disease (HHD) is challenging. We identify cardiovascular magnetic resonance (CMR) predictors of HHD over HCM when EDWT ≥15 mm. 2481 consecutive clinical CMRs between 2014 and 2015 were reviewed. 464 segments from 29 HCM subjects with EDWT ≥15 mm but without other cardiac abnormality, hypertension or renal impairment were analyzed. 432 segments from 27 HHD subjects with EDWT ≥15 mm but without concomitant cardiac pathology were analyzed. Magnitude and location of maximal EDWT, presence of late gadolinium enhancement (LGE), LV asymmetry (>1.5-fold opposing segment) and systolic anterior motion of the mitral valve (SAM) were measured. Multivariate logistic regression was performed. Significance was defined as p<0.05. HHD and HCM cohorts were age-/gender-matched. HHD had significantly increased indexed LV mass (110±27 g/m{sup 2} vs. 91±31 g/m{sup 2}, p=0.016) but no difference in site or magnitude of maximal EDWT. Mid-wall LGE was significantly more prevalent in HCM. Elevated indexed LVM, mid-wall LGE and absence of SAM were significant multivariate predictors of HHD, but LV asymmetry was not. Increased indexed LV mass, absence of mid-wall LGE and absence of SAM are better CMR discriminators of HHD from HCM than EDWT ≥15 mm. circle Hypertrophic cardiomyopathy (HCM) is often diagnosed with end-diastolic wall thickness ≥15 mm. (orig.)

  8. Hypertensive heart disease versus hypertrophic cardiomyopathy: multi-parametric cardiovascular magnetic resonance discriminators when end-diastolic wall thickness ≥ 15 mm

    International Nuclear Information System (INIS)

    Rodrigues, Jonathan C.L.; Rohan, Stephen; Ghosh Dastidar, Amardeep; Harries, Iwan; Lawton, Christopher B.; Ratcliffe, Laura E.; Burchell, Amy E.; Nightingale, Angus K.; Hart, Emma C.; Paton, Julian F.R.; Hamilton, Mark C.K.; Manghat, Nathan E.

    2017-01-01

    European guidelines state left ventricular (LV) end-diastolic wall thickness (EDWT) ≥15 mm suggests hypertrophic cardiomyopathy (HCM), but distinguishing from hypertensive heart disease (HHD) is challenging. We identify cardiovascular magnetic resonance (CMR) predictors of HHD over HCM when EDWT ≥15 mm. 2481 consecutive clinical CMRs between 2014 and 2015 were reviewed. 464 segments from 29 HCM subjects with EDWT ≥15 mm but without other cardiac abnormality, hypertension or renal impairment were analyzed. 432 segments from 27 HHD subjects with EDWT ≥15 mm but without concomitant cardiac pathology were analyzed. Magnitude and location of maximal EDWT, presence of late gadolinium enhancement (LGE), LV asymmetry (>1.5-fold opposing segment) and systolic anterior motion of the mitral valve (SAM) were measured. Multivariate logistic regression was performed. Significance was defined as p<0.05. HHD and HCM cohorts were age-/gender-matched. HHD had significantly increased indexed LV mass (110±27 g/m"2 vs. 91±31 g/m"2, p=0.016) but no difference in site or magnitude of maximal EDWT. Mid-wall LGE was significantly more prevalent in HCM. Elevated indexed LVM, mid-wall LGE and absence of SAM were significant multivariate predictors of HHD, but LV asymmetry was not. Increased indexed LV mass, absence of mid-wall LGE and absence of SAM are better CMR discriminators of HHD from HCM than EDWT ≥15 mm. circle Hypertrophic cardiomyopathy (HCM) is often diagnosed with end-diastolic wall thickness ≥15 mm. (orig.)

  9. Quantitative assessment of left ventricular systolic wall thickening using multidetector computed tomography

    DEFF Research Database (Denmark)

    Kristensen, Thomas S; Kofoed, Klaus F; Møller, Daniel V

    2009-01-01

    BACKGROUND: Multidetector computed tomography (MDCT) of the heart provides both anatomical and functional information. The objective of this study was to evaluate the accuracy of quantitative assessment of left ventricular contractile function in relation to two-dimensional transthoracic echocard......BACKGROUND: Multidetector computed tomography (MDCT) of the heart provides both anatomical and functional information. The objective of this study was to evaluate the accuracy of quantitative assessment of left ventricular contractile function in relation to two-dimensional transthoracic...... echocardiography (TTE). MATERIALS AND METHODS: Sixty-four patients with known or suspected coronary artery disease underwent ECG-gated 64-slice MDCT and TTE. Regional left ventricular contractile function was measured by percent systolic wall thickening (SWT) in 16 myocardial segments using MDCT, and compared...

  10. 31P-MR spectroscopy of all regions of the human heart at 1.5 T with acquisition-weighted chemical shift imaging

    International Nuclear Information System (INIS)

    Koestler, H.; Beer, M.; Buchner, S.; Sandstede, J.; Pabst, T.; Kenn, W.; Hahn, D.

    2001-01-01

    Aim: Aim of this study was to show whether or not acquisition-weighted chemical shift imaging (AW-CSI) allows the determination of PCr and ATP in the lateral and posterior wall of the human heart at 1.5 T. Methods: 12 healthy volunteers were examined using a conventional chemical shift imaging (CSI) and an AW-CSI. The sequences differed only in the number of repetitions for each point in k space. A hanning function was used as filter function leading to 7 repetitions in the center of the k space and 0 in the corners. Thus, AW-CSI had the same resolution as the CSI sequence. The results for both sequences were analyzed using identically positioned voxels in the septal, anterior, lateral and posterior wall. Results: The determined averaged AW-CSI signal to noise ratios were higher for PCr by a factor of 1.3 and for ATP by 1.4 than those of CSI. The PCr/ATP ratios were higher by a factor of 1.2 - 1.3 and showed a smaller standard deviation in all locations for AW-CSI. The mean PCr/ATP ratios determined by AW-CSI of septal, lateral and posterior wall were almost identical (1.72 - 1.76), while it was higher in the anterior wall (1.9). Conclusions: The reduced contamination in AW-CSI improves the signal to noise ratio and the determination of the PCr/ATP ratio in cardiac 31 P spectroscopy compared to CSI with the same resolution. The results in volunteers indicate that AW-CSI renders 31 P spectroscopy of the lateral and posterior wall of the human heart feasible for patient studies at 1.5 T. (orig.) [de

  11. Measurement of global and regional left ventricular performance with isotope technique in coronary heart disease

    International Nuclear Information System (INIS)

    Bostroem, P.-A.; Svensson, M.; Lilja, B.

    1988-01-01

    To evaluate left ventricular function in coronary artery disease, radionuclide measurements of global and regional ejection fraction (EF), regional wall motion and phase analyses of left ventricular contraction were performed by equilibrium technique, using sup(99m)Tc. One group of patients with angina pectoris and one group with myocardial infarction were compared with a control group. All above-mentioned parameters significantly separated the infarction group from the reference group both at rest and during work, while the group of patients with angina pectoris showed disturbances mainly during work, such as impaired ability to increase global and regional ejection fraction and regional wall motion. Adding regional analysis and phase analysis to the global EF determination increases the possibility of studying the left ventricular function. However, this addition has a limited value in detecting impaired left ventricular function compared to the determination of just global EF in patients with angina pectoris and in patients with myocardial infarction. (author)

  12. DGCR6 at the proximal part of the DiGeorge critical region is involved in conotruncal heart defects

    Science.gov (United States)

    Gao, Wenming; Higaki, Takashi; Eguchi-Ishimae, Minenori; Iwabuki, Hidehiko; Wu, Zhouying; Yamamoto, Eiichi; Takata, Hidemi; Ohta, Masaaki; Imoto, Issei; Ishii, Eiichi; Eguchi, Mariko

    2015-01-01

    Cardiac anomaly is one of the hallmarks of DiGeorge syndrome (DGS), observed in approximately 80% of patients. It often shows a characteristic morphology, termed as conotruncal heart defects. In many cases showing only the conotruncal heart defect, deletion of 22q11.2 region cannot be detected by fluorescence in situ hybridization (FISH), which is used to detect deletion in DGS. We investigated the presence of genomic aberrations in six patients with congenital conotruncal heart defects, who show no deletion at 22q11.2 in an initial screening by FISH. In these patients, no abnormalities were identified in the coding region of the TBX1 gene, one of the key genes responsible for the phenotype of DGS. However, when copy number alteration was analyzed by high-resolution array analysis, a small deletion or duplication in the proximal end of DiGeorge critical region was detected in two patients. The affected region contains the DGCR6 and PRODH genes. DGCR6 has been reported to affect the expression of the TBX1 gene. Our results suggest that altered dosage of gene(s) other than TBX1, possibly DGCR6, may also be responsible for the development of conotruncal heart defects observed in patients with DGS and, in particular, in those with stand-alone conotruncal heart defects. PMID:27081520

  13. Regional differences in right versus left congenital heart disease diagnoses in neonates in the United States.

    Science.gov (United States)

    Nelson, Jennifer S; Strassle, Paula D

    2018-03-01

    Differences in the prevalence of left and right congenital heart defects (CHD) across the United States are unclear. This study evaluated the overall prevalence and the distribution of right versus left CHD across US regions and divisions in neonates. Newborns born from 2000 to 2014 diagnosed with CHD were identified using the National Inpatient Sample. Heart defects were stratified into right, left, and "neither" subtypes. The risk of right and left heart diagnoses between US Census regions and divisions was compared using multivariable binomial regression, adjusting for infant, and hospital characteristics. Two hundred forty thousand four hundred fifty-five newborns were included and 38,185 (15.9%) were classifiable as having either right or left subtypes. Between 2000 and 2014, the prevalence of right defects increased from 1.65 to 2.88 cases/1,000 live born infants (p right heart defect diagnosis compared to the West. When stratified by division, New England states had a significantly higher prevalence of right defects compared to the Pacific (RD adj .09, 95% CI .06, 0.11). No differences in the prevalence of left defects were seen. The prevalence of CHD diagnoses at birth in the US has increased, and regional differences in the prevalence of right defects appear to exist. © 2017 Wiley Periodicals, Inc.

  14. A predominance of hypertensive heart disease among patients with cardiac disease in buea, a semi-urban setting, South west region of cameroon

    NARCIS (Netherlands)

    Nkoke, Clovis; Makoge, Christelle; Dzudie, Anastase; Mfeukeu, Liliane Kuate; Luchuo, Engelbert Bain; Menanga, Alain; Kingue, Samuel

    2017-01-01

    Objective: The pattern of heart disease is diverse within and among world regions. The little data on the spectrum of heart disease in Cameroon has been so far limited to major cities. We sought to describe the pattern of heart disease in Buea, the South West Region of Cameroon, a semi-urban

  15. 2D-speckle tracking right ventricular strain to assess right ventricular systolic function in systolic heart failure. Analysis of the right ventricular free and posterolateral walls.

    Science.gov (United States)

    Mouton, Stéphanie; Ridon, Héléne; Fertin, Marie; Pentiah, Anju Duva; Goémine, Céline; Petyt, Grégory; Lamblin, Nicolas; Coisne, Augustin; Foucher-Hossein, Claude; Montaigne, David; de Groote, Pascal

    2017-10-15

    Right ventricular (RV) systolic function is a powerful prognostic factor in patients with systolic heart failure. The accurate estimation of RV function remains difficult. The aim of the study was to determine the diagnostic accuracy of 2D-speckle tracking RV strain in patients with systolic heart failure, analyzing both free and posterolateral walls. Seventy-six patients with dilated cardiopathy (left ventricular end-diastolic volume≥75ml/m 2 ) and left ventricular ejection fraction≤45% had an analysis of the RV strain. Feasibility, reproducibility and diagnostic accuracy of RV strain were analyzed and compared to other echocardiographic parameters of RV function. RV dysfunction was defined as a RV ejection fraction≤40% measured by radionuclide angiography. RV strain feasibility was 93.9% for the free-wall and 79.8% for the posterolateral wall. RV strain reproducibility was good (intra-observer and inter-observer bias and limits of agreement of 0.16±1.2% [-2.2-2.5] and 0.84±2.4 [-5.5-3.8], respectively). Patients with left heart failure have a RV systolic dysfunction that can be unmasked by advanced echocardiographic imaging: mean RV strain was -21±5.7% in patients without RV dysfunction and -15.8±5.1% in patients with RV dysfunction (p=0.0001). Mean RV strain showed the highest diagnostic accuracy to predict depressed RVEF (area under the curve (AUC) 0.75) with moderate sensitivity (60.5%) but high specificity (87.5%) using a cutoff value of -16%. RV strain seems to be a promising and more efficient measure than previous RV echocardiographic parameters for the diagnosis of RV systolic dysfunction. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Idiopathic dilated cardiomyopathy: computerized anatomic study of relashionship between septal and free left ventricle wall.

    Science.gov (United States)

    Juliani, Paulo Sérgio; Costa, Eder França da; Correia, Aristides Tadeu; Monteiro, Rosangela; Jatene, Fabio Biscegli

    2014-01-01

    A feature of dilated cardiomyopathy is the deformation of ventricular cavity, which contributes to systolic dysfunction. Few studies have evaluated this deformation bearing in mind ventricular regions and segments of the ventricle, which could reveal important details of the remodeling process, supporting a better understanding of its role in functional impairment and the development of new therapeutic strategies. To evaluate if, in basal, equatorial and apical regions, increased internal transverse perimeter of left ventricle in idiopathic dilated cardiomyopathy occurs proportionally between the septal and non-septal segment. We performed an anatomical study with 28 adult hearts from human cadavers. One group consisted of 18 hearts with idiopathic dilated cardiomyopathy and another group with 10 normal hearts. After lamination and left ventricle digital image capture, in three different regions (base, equator and apex), the transversal internal perimeter of left ventricle was divided into two segments: septal and not septal. These segments were measured by proper software. It was established an index of proportionality between these segments, called septal and non-septal segment index. Then we determined whether this index was the same in both groups. Among patients with normal hearts and idiopathic dilated cardiomyopathy, the index of proportionality between the two segments (septal and non-septal) showed no significant difference in the three regions analyzed. The comparison results of the indices NSS/SS among normal and enlarged hearts were respectively: in base 1.99 versus 1.86 (P=0.46), in equator 2.22 versus 2.18 (P=0.79) and in apex 2.96 versus 3.56 (P=0.11). In the idiopathic dilated cardiomyopathy, the transversal dilatation of left ventricular internal perimeter occurs proportionally between the segments corresponding to the septum and free wall at the basal, equatorial and apical regions of this chamber.

  17. Chemical and structural analysis of Eucalyptus globulus and E. camaldulensis leaf cuticles: a lipidized cell wall region

    Directory of Open Access Journals (Sweden)

    Paula eGuzmán

    2014-09-01

    Full Text Available The plant cuticle has traditionally been conceived as an independent hydrophobic layer that covers the external epidermal cell wall. Due to its complexity, the existing relationship between cuticle chemical composition and ultra-structure remains unclear to date. This study aimed to examine the link between chemical composition and structure of isolated, adaxial leaf cuticles of Eucalyptus camaldulensis and E. globulus by the gradual extraction and identification of lipid constituents (cutin and soluble lipids, coupled to spectroscopic and microscopic analyses. The soluble compounds and cutin monomers identified could not be assigned to a concrete internal cuticle ultra-structure. After cutin depolymerization, a cellulose network resembling the cell wall was observed, with different structural patterns in the regions ascribed to the cuticle proper and cuticular layer, respectively. Our results suggest that the current cuticle model should be revised, stressing the presence and major role of cell wall polysaccharides. It is concluded that the cuticle may be interpreted as a modified cell wall region which contains additional lipids. The major heterogeneity of the plant cuticle makes it difficult to establish a direct link between cuticle chemistry and structure with the existing methodologies.

  18. Noninvasive assessment of right ventricular wall motion by radionuclide cardioangiography

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshiisa; Naito, Hiroaki; Hayashida, Kohei; Kozuka, Takahiro

    1981-01-01

    Radionuclide cardioangiography is a useful method to evaluate the left ventricular wall motion in various heart diseases. It has been also attempted to assess the right ventricular wall motion simultaneously by radionuclide method. In this study, using the combination of first-pass (RAO 30 0 ) and multi-gate (LAO 40 0 ) method, the site of right vetricle was classified in five. (1 inflow, 2 sinus, 3 outflow, 4 septal, 5 lateral) and the degree of wall motion was classified in four stages (dyskinesis, akinesis, hypokinesis, normal) according to the AHA committee report. These methods were applied clinically to forty-eight patients with various heart diseases. In the cases with right ventricular pressure or volume overload such as COLD, pulmonary infarction, the right ventricle was dilated and the wall motion was reduced in all portions. Especially, in the cases with right ventricular infarction, the right ventricular wall motion was reduced in the infarcted area. The findings of radionuclide method were in good agreement with those of contrast right ventriculography or echocardiography. In conclusion, radionuclide cardioangiography is a useful and noninvasive method to assess not only the left but also the right ventricular wall motion. (author)

  19. Diagnostic assessment of the heart after infarction: what is the role of magnetic resonance imaging?

    International Nuclear Information System (INIS)

    Kivelitz, D.E.; Taupitz, M.; Hamm, B.

    1999-01-01

    There have been considerable advances in the diagnostic assessment of the heart by magnetic resonance imaging (MRI) in recent years. Thus, MRI as a one-stop shop modality for the comprehensive noninvasive evaluation of coronary heart disease and myocardial infarction may soon become a reality. This article presents an overview of the present possibilities and future potential of evaluating myocardial anatomy, function, perfusion, and coronary anatomy after myocardial infarction. Cine MRI provides a reliable analysis of regional and global disturbances of cardiac wall motion with a high temporal and spatial resolution. Tagging techniques permit the noninvasive labelling of parts of the myocardium and the identification of three-dimensional patterns of contraction. Myocardial perfusion and disturbed wall motion under pharmacologic stress can be reliably assessed by MRI as well. What is unique is the visualization of myocardial edema, which is made possible by the high soft-tissue contrast resolution. The as yet limited potential to assess coronary arteries and coronary bypasses is likewise discussed. (orig.) [de

  20. Isomyosin expression patterns during rat heart morphogenesis: an immunohistochemical study

    NARCIS (Netherlands)

    de Groot, I. J.; Lamers, W. H.; Moorman, A. F.

    1989-01-01

    An immunohistochemical study of cardiac alpha and beta myosin heavy chain (MHC) expression during rat heart morphogenesis was performed. In tubular hearts (embryonic days, ED10-11) coexpression of both cardiac alpha and beta MHC was found throughout the heart, except for the left free wall of the

  1. Mortality by Heart Failure and Ischemic Heart Disease in Brazil from 1996 to 2011

    International Nuclear Information System (INIS)

    Gaui, Eduardo Nagib; Oliveira, Gláucia Maria Moraes de; Klein, Carlos Henrique

    2014-01-01

    Circulatory system diseases are the first cause of death in Brazil. To analyze the evolution of mortality caused by heart failure, by ischemic heart diseases and by ill-defined causes, as well as their possible relations, in Brazil and in the geoeconomic regions of the country (North, Northeast, Center-West, South and Southeast), from 1996 to 2011. Data were obtained from DATASUS and death declaration records with codes I20 and I24 for acute ischemic diseases, I25 for chronic ischemic diseases, and I50 for heart failure, and codes in chapter XIII for ill-defined causes, according to geoeconomic regions of Brazil, from 1996 to 2011. Mortality rates due to heart failure declined in Brazil and its regions, except for the North and the Northeast. Mortality rates due to acute ischemic heart diseases increased in the North and Northeast regions, especially from 2005 on; they remained stable in the Center-West region; and decreased in the South and in the Southeast. Mortality due to chronic ischemic heart diseases decreased in Brazil and in the Center-West, South and Southeast regions, and had little variation in the North and in the Northeast. The highest mortality rates due to ill-defined causes occurred in the Northeast until 2005. Mortality due to heart failure is decreasing in Brazil and in all of its geoeconomic regions. The temporal evolution of mortality caused by ischemic heart diseases was similar to that of heart failure. The decreasing number of deaths due to ill-defined causes may represent the improvement in the quality of information about mortality in Brazil. The evolution of acute ischemic heart diseases ranged according to regions, being possibly confused with the differential evolution of ill-defined causes

  2. Mortality by Heart Failure and Ischemic Heart Disease in Brazil from 1996 to 2011

    Directory of Open Access Journals (Sweden)

    Eduardo Nagib Gaui

    2014-06-01

    Full Text Available Background: Circulatory system diseases are the first cause of death in Brazil. Objective: To analyze the evolution of mortality caused by heart failure, by ischemic heart diseases and by ill-defined causes, as well as their possible relations, in Brazil and in the geoeconomic regions of the country (North, Northeast, Center-West, South and Southeast, from 1996 to 2011. Methods: Data were obtained from DATASUS and death declaration records with codes I20 and I24 for acute ischemic diseases, I25 for chronic ischemic diseases, and I50 for heart failure, and codes in chapter XIII for ill-defined causes, according to geoeconomic regions of Brazil, from 1996 to 2011. Results: Mortality rates due to heart failure declined in Brazil and its regions, except for the North and the Northeast. Mortality rates due to acute ischemic heart diseases increased in the North and Northeast regions, especially from 2005 on; they remained stable in the Center-West region; and decreased in the South and in the Southeast. Mortality due to chronic ischemic heart diseases decreased in Brazil and in the Center-West, South and Southeast regions, and had little variation in the North and in the Northeast. The highest mortality rates due to ill-defined causes occurred in the Northeast until 2005. Conclusions: Mortality due to heart failure is decreasing in Brazil and in all of its geoeconomic regions. The temporal evolution of mortality caused by ischemic heart diseases was similar to that of heart failure. The decreasing number of deaths due to ill-defined causes may represent the improvement in the quality of information about mortality in Brazil. The evolution of acute ischemic heart diseases ranged according to regions, being possibly confused with the differential evolution of ill-defined causes.

  3. Mortality by Heart Failure and Ischemic Heart Disease in Brazil from 1996 to 2011

    Energy Technology Data Exchange (ETDEWEB)

    Gaui, Eduardo Nagib, E-mail: engaui@cardiol.br; Oliveira, Gláucia Maria Moraes de [Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil); Klein, Carlos Henrique [Escola Nacional de Saúde Pública Sérgio Arouca da Fundação Oswaldo Cruz, Rio de Janeiro, RJ (Brazil)

    2014-06-15

    Circulatory system diseases are the first cause of death in Brazil. To analyze the evolution of mortality caused by heart failure, by ischemic heart diseases and by ill-defined causes, as well as their possible relations, in Brazil and in the geoeconomic regions of the country (North, Northeast, Center-West, South and Southeast), from 1996 to 2011. Data were obtained from DATASUS and death declaration records with codes I20 and I24 for acute ischemic diseases, I25 for chronic ischemic diseases, and I50 for heart failure, and codes in chapter XIII for ill-defined causes, according to geoeconomic regions of Brazil, from 1996 to 2011. Mortality rates due to heart failure declined in Brazil and its regions, except for the North and the Northeast. Mortality rates due to acute ischemic heart diseases increased in the North and Northeast regions, especially from 2005 on; they remained stable in the Center-West region; and decreased in the South and in the Southeast. Mortality due to chronic ischemic heart diseases decreased in Brazil and in the Center-West, South and Southeast regions, and had little variation in the North and in the Northeast. The highest mortality rates due to ill-defined causes occurred in the Northeast until 2005. Mortality due to heart failure is decreasing in Brazil and in all of its geoeconomic regions. The temporal evolution of mortality caused by ischemic heart diseases was similar to that of heart failure. The decreasing number of deaths due to ill-defined causes may represent the improvement in the quality of information about mortality in Brazil. The evolution of acute ischemic heart diseases ranged according to regions, being possibly confused with the differential evolution of ill-defined causes.

  4. Myocardial temperature variation: effect on regional function and coronary flow in dogs

    International Nuclear Information System (INIS)

    D'Ambra, M.N.; Magrassi, P.; Lowenstein, E.; Kyo, S.; Austen, W.G.; Buckley, M.J.; LaRaia, P.J.

    1987-01-01

    Incremental changes in the temperature (28-42.5 0 C) of the anterior left ventricular wall in a canine, working, beating right heart bypass preparation (constant preload, afterload, and heart rate) were produced to measure the effect of regional temperature on myocardial function and blood flow. Circumferential-axis segment lengths were measured with sonomicrometry in both the temperature-varied, left-anterior descending coronary artery (LAD)-supplied myocardium and the normothermic (38 0 C) circumflex-supplied myocardium. Fast thermistors (time constant 0 C), regional systolic shortening decreased 42.2 +/- 10% at 41 0 C and increased 23.3 +/- 6% at 31 0 C. There was no significant change in coronary blood flow or distribution at the three temperatures. Pressure-length areas varied inversely with myocardial temperature. These data demonstrate that there is a reversible inverse relationship between midwall T and ventricular function when heart rate, preload, and afterload are controlled

  5. NMR-tomography of the heart

    International Nuclear Information System (INIS)

    Weikl, A.; Bachmann, K.

    1987-01-01

    The NMR-tomography as a non-invasive imaging process is examined regarding to the value to answer clinical issues. This method allows an evaluation of qualitative, quantitative, morphological and functional parameters. The diagnostic use on the heart shows early myocardial changes, thrombosis, changes in the dynamics of the left ventricle (EDV, ESV, EF), the quantitative wall movement and the blood flow in a shunt defect. The placed value of echocardiography, myocardial scintigraphy and coronary angiography in the diagnosis of acquired valvular heart disease, myocardial perfusion and coronary heart disease is not lowered by the above mentioned method. (orig.) [de

  6. NMR-tomography of the heart

    Energy Technology Data Exchange (ETDEWEB)

    Weikl, A.; Bachmann, K.

    1987-04-03

    The NMR-tomography as a non-invasive imaging process is examined regarding to the value to answer clinical issues. This method allows an evaluation of qualitative, quantitative, morphological and functional parameters. The diagnostic use on the heart shows early myocardial changes, thrombosis, changes in the dynamics of the left ventricle (EDV, ESV, EF), the quantitative wall movement and the blood flow in a shunt defect. The placed value of echocardiography, myocardial scintigraphy and coronary angiography in the diagnosis of acquired valvular heart disease, myocardial perfusion and coronary heart disease is not lowered by the above mentioned method.

  7. Percutaneous Implantation of A Parachute Device For Treatment of Ischemic Heart Failure

    Energy Technology Data Exchange (ETDEWEB)

    Cilingiroglu, Mehmet, E-mail: mcilingiroglu@yahoo.com; Rollefson, William A.; Mego, David

    2013-07-15

    Congestive heart failure (CHF) secondary to ischemic cardiomyopathy is associated with significant morbidity and mortality despite currently available medical therapy. The Parachute{sup TM} device is a novel left ventricular partitioning device that is delivered percutaneously in the left ventricle (LV) in patients with anteroapical regional wall motion abnormalities, dilated LV and systolic dysfunction after anterior myocardial infarction with favorable clinical and LV hemodynamic improvements post-implantation. Here, we do review the current literature and present a case of the Parachute device implantation.

  8. Percutaneous Implantation of A Parachute Device For Treatment of Ischemic Heart Failure

    International Nuclear Information System (INIS)

    Cilingiroglu, Mehmet; Rollefson, William A.; Mego, David

    2013-01-01

    Congestive heart failure (CHF) secondary to ischemic cardiomyopathy is associated with significant morbidity and mortality despite currently available medical therapy. The Parachute TM device is a novel left ventricular partitioning device that is delivered percutaneously in the left ventricle (LV) in patients with anteroapical regional wall motion abnormalities, dilated LV and systolic dysfunction after anterior myocardial infarction with favorable clinical and LV hemodynamic improvements post-implantation. Here, we do review the current literature and present a case of the Parachute device implantation

  9. Direct measurements of wall shear stress by buried wire gages in a shock-wave boundary-layer interaction region

    Science.gov (United States)

    Murthy, V. S.; Rose, W. C.

    1977-01-01

    Detailed measurements of wall shear stress (skin friction) were made with specially developed buried wire gages in the interaction regions of a Mach 2.9 turbulent boundary layer with externally generated shocks. Separation and reattachment points inferred by these measurements support the findings of earlier experiments which used a surface oil flow technique and pitot profile measurements. The measurements further indicate that the boundary layer tends to attain significantly higher skin-friction values downstream of the interaction region as compared to upstream. Comparisons between measured wall shear stress and published results of some theoretical calculation schemes show that the general, but not detailed, behavior is predicted well by such schemes.

  10. Regional Longitudinal Deformation Improves Prediction of Ventricular Tachyarrhythmias in Patients With Heart Failure With Reduced Ejection Fraction

    DEFF Research Database (Denmark)

    Biering-Sørensen, Tor; Knappe, Dorit; Pouleur, Anne-Catherine

    2017-01-01

    BACKGROUND: Left ventricular dysfunction is a known predictor of ventricular arrhythmias. We hypothesized that measures of regional longitudinal deformation by speckle-tracking echocardiography predict ventricular tachyarrhythmias and provide incremental prognostic information over clinical...... in the model, only a decreasing myocardial function in the inferior myocardial wall predicted VT/VF (hazard ratio, 1.05 [1.00-1.11]; P=0.039). Only strain obtained from the inferior myocardial wall provided incremental prognostic information for VT/VF over clinical and echocardiographic parameters (C statistic...... 0.71 versus 0.69; P=0.005). CONCLUSIONS: Assessment of regional longitudinal myocardial deformation in the inferior region provided incremental prognostic information over clinical and echocardiographic risk factors in predicting ventricular tachyarrhythmias. CLINICAL TRIAL REGISTRATION: URL: http...

  11. Patterns of presentation of chronic ischemic heart disease with and without previous myocardial infarction

    International Nuclear Information System (INIS)

    Ahmad, R.; Rabbani, A.; Awan, Z.A.

    2009-01-01

    The prevalence of Ischemic Heart Disease (IHD) is on the rise, from increasing lifespan of population and availability of better medical facilities. We studied chronic IHD cases with and without previous myocardial infarction, in Hazara, NWFP, Pakistan to evaluate left ventricular (LV) dysfunction, wall motion abnormalities and complications of IHD. All patients presenting with history of chest pain in Medical 'C' Unit, Ayub Teaching Hospital, Abbottabad from June 2004 to May 2005 were included in the study. Patients with non-cardiac chest pain were excluded from the study. Cases with congenital and rheumatic heart disease, cardiomyopathies, unstable angina and acute MI were excluded. Patients with IHD with or without myocardial infarction (MI) were studied for left ventricular dysfunction (ejection fraction, left atrial size, E/A ratio), wall motion abnormalities and complications of IHD (Mitral regurgitation, Ventricular Septal Defect (VSD), LV aneurysm, LV clot). Clinical and echocardiographic evaluation was done in each case. Out of 183 cases of chronic IHD, 123 patients were without previous MI and 60 had had previous MI. Ejection fraction (EF) was 45%+-15 in the group without MI and 35+-11% in cases with MI. Left Atrium (LA) size was 35+-6 mm and 39+-4 mm in the two groups respectively. LV diastolic dysfunction was seen in 17% in the first and 24% in the second group respectively. Global hypokinesia was seen in 8% and 17% in the 2 groups respectively. Regional Wall Motion Abnormality (RWMA) was observed in 12% in patients without MI and in 58% cases with MI. Mitral regurgitation was seen in 10 and 20% in the 2 groups respectively LV clots, VSD, LV and aneurysm were seen in 8.4, 5, and 6.5% respectively, only in cases with previous MI. LV dysfunction, wall motion abnormalities and mitral regurgitation were more common in IHD cases with previous heart attack. (author)

  12. The Evaluation of a Regional Faith Community Network's Million Hearts Program.

    Science.gov (United States)

    Cooper, Jennifer; Zimmerman, Wendy

    2016-01-01

    The goal of the Million Hearts initiative is to prevent one million heart attacks and strokes by 2017. Maryland was one state in the Association of State and Territorial Health Official's Million Hearts State Learning Collaborative. Washington County, Maryland formed a collaboration between the County Health Department, Meritus Health System, and the Meritus Health Parish Nurse Coordinator to address hypertension in the county. Within a regional network of 52 faith communities, the Parish Nurse Coordinator recruited 25 faith community nurses to participate in a three-month program. Nurses were trained on proper blood pressure measurement and 22 nurses identified 58 participants engaged in blood pressure self-monitoring and coaching for lifestyle changes. Additionally, nurses took 1,729 blood pressures and provided health education to individuals within their congregations. Fifty-one participants participated in blood pressure self-monitoring and lifestyle coaching with faith community nurses. There was improvement in six out of seven lifestyle areas. Eight-two percent of participants (N = 42) decreased their systolic and/or diastolic blood pressure over three months. Coaching provided by faith community nurses can create an environment of sustained support to promote improved lifestyle and blood pressure changes over time. © 2015 Wiley Periodicals, Inc.

  13. Regeneration of near-wall turbulence structures

    Science.gov (United States)

    Hamilton, James M.; Kim, John J.; Waleffe, Fabian A.

    1993-01-01

    An examination of the regeneration mechanisms of near-wall turbulence and an attempt to investigate the critical Reynolds number conjecture of Waleffe & Kim is presented. The basis is an extension of the 'minimal channel' approach of Jimenez and Moin which emphasizes the near-wall region and further reduces the complexity of the turbulent flow. Reduction of the flow Reynolds number to the minimum value which will allow turbulence to be sustained has the effect of reducing the ratio of the largest scales to the smallest scales or, equivalently, of causing the near-wall region to fill more of the area between the channel walls. In addition, since each wall may have an active near-wall region, half of the channel is always somewhat redundant. If a plane Couette flow is instead chosen as the base flow, this redundancy is eliminated: the mean shear of a plane Couette flow has a single sign, and at low Reynolds numbers, the two wall regions share a single set of structures. A minimal flow with these modifications possesses, by construction, the strongest constraints which allow sustained turbulence, producing a greatly simplified flow in which the regeneration process can be examined.

  14. Assessment of left ventricular filling in various heart disease, especially in ischemic heart disease, by ECG-gated cardiac blood pool scintigraphy

    International Nuclear Information System (INIS)

    Nakagawa, Hiroaki

    1986-01-01

    Using ECG-gated cardiac blood pool scintigraphy (BPS), left ventricular (LV) diastolic function was evaluated in various heart disease, especially in ischemic heart disease (IHD). LV function indices (2 systolic and 9 diastolic) were obtained from LV time activity curve derived from BPS. Among various diastolic indices, peak filling rate (PFR) and 2 other indices were significantly influenced by heart rate (HR), so corrected values for HR were used for this study. Various degrees of disturbance in diastolic filling were found in many cases without systolic impairment. According to the mechanism responsible for diastolic impairment, LV time activity curve showed a characteristic pattern. In IHD, filling disturbance in early diastole was observed before the impairment of systolic contraction developed, so it was thought to be an early predictor of cardiac failure. In the scar region of myocardial infarction (MI), decrease in regional ejection fraction and asynchrony in wall motion were shown, and these resulted in marked deterioration of early diastolic filling. On the other hand in angina pectoris (AP), such systolic disorders were not shown in the ischemic region perfused by stenotic coronary artery, although the disturbance of regional filling was found. The exercise capacity in AP was more related to the impairment in diastolic function at resting state than in systolic function, and furthermore the reserve of diastolic function as well as of systolic function was shown to be an important determinant of exercise capacity in AP. As HR increased, increase of PFR and decrease in time to peak filling was found, which was thought to be a sort of compensation for the shortening diastolic time due to increase in HR during exercise. Such compensation was decreased in AP with reduced exercise capacity. (J.P.N.)

  15. Single-walled carbon nanotubes based chemiresistive genosensor for label-free detection of human rheumatic heart disease

    Science.gov (United States)

    Singh, Swati; Kumar, Ashok; Khare, Shashi; Mulchandani, Ashok; Rajesh

    2014-11-01

    A specific and ultrasensitive, label free single-walled carbon nanotubes (SWNTs) based chemiresistive genosensor was fabricated for the early detection of Streptococcus pyogenes infection in human causing rheumatic heart disease. The mga gene of S. pyogenes specific 24 mer ssDNA probe was covalently immobilized on SWNT through a molecular bilinker, 1-pyrenemethylamine, using carbodiimide coupling reaction. The sensor was characterized by the current-voltage (I-V) characteristic curve and scanning electron microscopy. The sensing performance of the sensor was studied with respect to changes in conductance in SWNT channel based on hybridization of the target S. pyogenes single stranded genomic DNA (ssG-DNA) to its complementary 24 mer ssDNA probe. The sensor shows negligible response to non-complementary Staphylococcus aureus ssG-DNA, confirming the specificity of the sensor only with S. pyogenes. The genosensor exhibited a linear response to S. pyogenes G-DNA from 1 to1000 ng ml-1 with a limit of detection of 0.16 ng ml-1.

  16. MRI of the heart, the great vessels and the mediastinum

    International Nuclear Information System (INIS)

    Obletter, N.; Picker, D.; Stirner, H.; Schmitt, R.; Helmberger, T.

    1994-01-01

    The article surveys the most important indications for MRT of the heart, the great vessels and the mediastinum. MRT is clearly indicated with search or clarification of aneurysms of the heart wall, atrial or ventriucular septal defects with shunting or other congenital vitia in children or in the newborn, aortic aneurysms as well as connatal defects. MRT is superior to other screening methods when clarifying mediastinal neoplasms because of its multiplanar presentation and its strong quality in contrasting soft tissue. With MRT impressive dynamic studies can be obtained through cine modes and gradient echo sequences, which are very successfully used for aortic and mitral valve stenoses, for aneurysms of the heart wall, for aortic aneurysms and atrial and septal shunts. (orig./MG) [de

  17. Simultaneous estimates of regional myocardial blood flow and metabolism by the developing chick heart using [201]thallium and [14C] 2-deoxyglucose autoradiography

    International Nuclear Information System (INIS)

    Kostreva, D.R.; Wood, J.D.

    1990-01-01

    Little is known about regional myocardial blood flow and metabolism in the developing heart. Simultaneous estimates of regional myocardial blood flow and glucose metabolism have been made in the adult rat by Yonekura et al using [ 201 ] Thallium (THAL) and [ 14 C]2-deoxyglucose (DG) autoradiography. Since glucose is the primary cardiac metabolic substrate during development, glucose utilization is also an estimate of myocardial metabolism. Examination and comparison of the THAL and DG autoradiographs revealed that there is an uncoupling of blood flow and metabolism in the developing chick heart. Areas of the heart which had marked glucose utilization did not always have marked blood flow. Regions of the heart which had marked blood flow but very little glucose utilization were the interventricular septum and the apex. One explanation for this disparity is that although blood flow may be established in these regions, normal cardiac function requiring significant substrate utilization may not be fully developed

  18. SU-F-T-92: Clinical Benefit for Breast and Chest Wall Setup in Using a Breast Board

    Energy Technology Data Exchange (ETDEWEB)

    Li, S; Miyamoto, C; Serratore, D; Liang, Q; Dziemianowicz, E [Temple University Hospital, Philadelphia, PA (United States)

    2016-06-15

    Purpose: To validate benefit of using a breast board (BB) by analyzing the geometry and dosimetry changes of the regions of interest (ROIs) between CT scans with and without BB. Methods: Seven patients, two chest walls (CW) and five breasts, use BB at CT simulation and no BB at diagnostic CT were included. By using deformable image registration software (Velocity AI), diagnostic CT and planning CT were rigidly co-registered according to the thoracic cage at the target. The heart and the target were then deformedly matched and the contours of the planned ROIs were transferred to the diagnostic CT. Which were brought back to the planning CT data set though the initial rigid co-registration in order to keep the deformed ROIs redefined in the diagnostic CT. Anatomic shifts and volume changes of a ROI beyond the rigid translation were recorded and dosimetry changes to ROIs were compared with recalculated DVHs. Results: Patient setup without the BB had small but systematic heart shifts superiorly by ∼5 mm. Torso rotations in two cases moved the heart in opposite directions by ∼10 mm. The breast target volume, shape, and locations were significantly changed with arm extension over the head but not in cases with the arm extended laterally. Breast setup without BB could increase the mean dose to the heart and the maximal dose to the anterior ventricle wall by 1.1 and 6.7 Gy, respectively. Conclusion: A method for evaluation of breast setup technique is introduced and applied for patients. Results of systematic heart displacement without using the BB and the potential increase of heart doses encourage us to further investigate the current trend of not using a BB for easy setup and CT scans. Using a BB would likely increase patient sag during prolonged IMRT and real-time patient position monitoring is clinically desired.

  19. Mediastinal and heart wall invasion by actinomycosis: CT and MRI appearances

    International Nuclear Information System (INIS)

    Fisch, C.; Schmutz, G.R.; Benko, A.J.; Kastler, B.

    1994-01-01

    Widespread use of antibiotics facilitates the development of some uncommon chronic infections such as actinomycosis. The clinical and radiographic findings overlap those of other inflammatory and neoplastic conditions. With a review of the literature, we report the CT and MRI findings in a case of thoracic actinomycosis, presenting with right ventricular failure caused by heart involvement. CT was helpful in identifying the mediastinal extent of the disease and in demonstrating the absence of pulmonary involvement. MRI, however, offered complementary information, especially in assessing heart involvement without the need for intravenous contrast media. On T2-weighted images the mediastinal process was noted to be of relatively low signal intensity, possibly indicating its benign nature. The association with heart involvement was suggestive of thoracic actinomycosis. (orig.)

  20. Evaluation of multi-gated myocardial perfusion imaging in various heart diseases

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshitake; Kozuka, Takahiro

    1980-01-01

    Multi-gated myocardial perfusion imaging were studied in a hundred cases of various heart diseases. In normal cases, ED ES images showed thinning and thickening of wall motion respectively to compare with static images. In the myocardial infarction cases, the dynamic changes of wall motion was decreased at infarcted areas in all cases. In congestive cardiomyopathy, the change of wall motion is smaller than normal cases in all cases, while in hypertrophic cardiomyopathy, the change is not so hyperdynamic to compare with normal cases and by multi-gated images, asymmetric hypertrophy was clearly detected in HCM than static images. In conclusion, these methods were useful to detect the myocardial contraction stage in various heart diseases. (author)

  1. Heart failure due to severe myocardial calcification

    International Nuclear Information System (INIS)

    Takahashi, Shouichi; Maida, Kiyoshi; Yokoyama, Hitoshi; Tanaka, Shigeo

    1993-01-01

    A 28-year-old female who had had irradiation on the chest wall at the age of 5 as a remedy for keloid granulation after burn, recently developed congestive heart failure. Severe tricuspid regurgitation was demonstrated by echocardiography with a certain calcification in the cardiac shadow on chest radiogram. Calcified right ventricle and ventricular septum were noticed operatively, which disturbed ventricular motion and also caused tricuspid valve deformity. These calcified myocardium apparently corresponded with the irradiation field. After tricuspid valve replacement, she regained physical activity satisfactorily without congestive heart failure. Because she had no other known causes of cardiac calcification such as hypercalcemia, myocarditis, myocardial infarction or renal diseases, irradiation on the chest wall could be responsible for the severe myocardial calcification. (author)

  2. Coronary artery wall imaging in mice using osmium tetroxide and micro-computed tomography (micro-CT)

    International Nuclear Information System (INIS)

    Pai, Vinay M.; Kozlowski, Megan; Donahue, Danielle; Miller, Elishiah; Xiao, Xianghui; Chen, Marcus Y.; Yu, Zu-Xi; Connelly, Patricia; Jeffries, Kenneth; Wen, Han

    2012-01-01

    The high spatial resolution of micro-computed tomography (micro-CT) is ideal for 3D imaging of coronary arteries in intact mouse heart specimens. Previously, micro-CT of mouse heart specimens utilized intravascular contrast agents that hardened within the vessel lumen and allowed a vascular cast to be made. However, for mouse coronary artery disease models, it is highly desirable to image coronary artery walls and highlight plaques. For this purpose, we describe an ex vivo contrast-enhanced micro-CT imaging technique based on tissue staining with osmium tetroxide (OsO 4 ) solution. As a tissue-staining contrast agent, OsO 4 is retained in the vessel wall and surrounding tissue during the fixation process and cleared from the vessel lumens. Its high X-ray attenuation makes the artery wall visible in CT. Additionally, since OsO 4 preferentially binds to lipids, it highlights lipid deposition in the artery wall. We performed micro-CT of heart specimens of 5- to 25-week-old C57BL/6 wild-type mice and 5- to 13-week-old apolipoprotein E knockout (apoE -/- ) mice at 10 μm resolution. The results show that walls of coronary arteries as small as 45 μm in diameter are visible using a table-top micro-CT scanner. Similar image clarity was achieved with 1/2000th the scan time using a synchrotron CT scanner. In 13-week-old apoE mice, lipid-rich plaques are visible in the aorta. Our study shows that the combination of OsO 4 and micro-CT permits the visualization of the coronary artery wall in intact mouse hearts.

  3. Thoracic and heart biometrics of non-anesthetized agouti (Dasyprocta primnolopha Wagler, 1831 measured on radiographic images

    Directory of Open Access Journals (Sweden)

    Anaemilia das N. Diniz

    2013-03-01

    Full Text Available The agouti is a species intensively hunted throughout the Amazon and the semi-arid regions of northeastern Brazil. Considering the current trend in conservation management of wild species, the aim of this study was to determine the morphometric reference to the heart of agouti raised in captivity, based on thoracic and cardiac measurements in these animals. Thirty adult agoutis, 1 to 3 years of age, without clinical signs of cardiac disease were selected. The animals were physically restrained and radiographies in laterolateral (LL and ventrodorsal (VD recumbence were produced. The following measures were taken: the apicobasilar length of the heart (at the most cranial height of the Carina region to the heart apex (AB, maximum width of the heart perpendicular to AB (CD, heart inclination angle (AIC, trachea inclination angle (AIT, distance from the right heart wall (DPTd, distance from the left heart wall (DPTe and vertical depth of the thorax, and the ventral face of the vertebral column to the dorsal border of the sternum at the level of the trachea bifurcation (H. The ratios between AB/CD, AB/H and CD/H were also analyzed. To calculate the vertebral heart scale (VHS, the AB and CD measurements were laid over the thoracic vertebra starting at T4. Radiographic evaluation showed values consistent with those reported in small animals and some wild and exotic species. The main biometric values in the chest cavity and heart of agouti are arranged as follows: (1 The ratios between AB/H ratio and CD/H were not sensitive for identifying heart increases (p>0.05, while the ratio AB/CD was more sensitive in this identification (p<0.05; (2 AIC: 21.2±6.4º (mean between male and famale; (3 AIT for males and females: 9.93±3.23° and 8.4±3.94°; (4 DPTd and DPTe for males: 0.97±0.40cm and 0.7±0.30cm; (5 DPTd and DPTe for females: 1.12±0.42cm and 01.02±0.43cm; (6 VHS for males and females: 7.75±0.48v e 7.61±0.34v; (7 The caudal vena cava (CVC was

  4. Necrotizing infection of the heart.

    Science.gov (United States)

    Ballard, David H; Pennington, George Patton; Pennington, George P; Johnson, Joe; Bhalla, Sanjeev; Raptis, Constantine

    2018-02-06

    A case of necrotizing infection of the heart is presented. A 70-year-old woman presented with vague chest and abdominal pain. CT of the abdomen and pelvis was initially obtained, which demonstrated gas in the myocardium of the left ventricle. Subsequent chest CT, endoscopy, and abdominal surgical exploration did not reveal perforated viscus or diaphragm compromise. At median sternotomy, the inferior wall of the heart was found to be necrotic. Culture of the excised tissue grew E. coli. The patient expired shortly after surgical exploration. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Physical principles of artificial stimulation of the heart : Stimulation of the canine heart in situ

    NARCIS (Netherlands)

    Schneider, H.

    1. 1. In artificial heart stimulation, the essential quantity is the density of current, , in the intramyocardial wall. Dosage of the pulse amplitude in volts can have serious consequences for the patient. Curve indications in volts on pacemakers and in publications and records must, therefore, be

  6. Swirling flow in bileaflet mechanical heart valve

    Science.gov (United States)

    Gataulin, Yakov A.; Khorobrov, Svyatoslav V.; Yukhnev, Andrey D.

    2018-05-01

    Bileaflet mechanical valves are most commonly used for heart valve replacement. Nowadays swirling blood flow is registered in different parts of the cardiovascular system: left ventricle, aorta, arteries and veins. In present contribution for the first time the physiological swirling flow inlet conditions are used for numerical simulation of aortic bileaflet mechanical heart valve hemodynamics. Steady 3-dimensional continuity and RANS equations are employed to describe blood motion. The Menter SST model is used to simulate turbulence effects. Boundary conditions are corresponded to systolic peak flow. The domain was discretized into hybrid tetrahedral and hexahedral mesh with an emphasis on wall boundary layer. A system of equations was solved in Ansys Fluent finite-volume package. Noticeable changes in the flow structure caused by inlet swirl are shown. The swirling flow interaction with the valve leaflets is analyzed. A central orifice jet changes its cross-section shape, which leads to redistribution of wall shear stress on the leaflets. Transvalvular pressure gradient and area-averaged leaflet wall shear stress increase. Physiological swirl intensity noticeably reduces downstream of the valve.

  7. Single-walled carbon nanotubes based chemiresistive genosensor for label-free detection of human rheumatic heart disease

    International Nuclear Information System (INIS)

    Singh, Swati; Kumar, Ashok; Khare, Shashi; Mulchandani, Ashok; Rajesh

    2014-01-01

    A specific and ultrasensitive, label free single-walled carbon nanotubes (SWNTs) based chemiresistive genosensor was fabricated for the early detection of Streptococcus pyogenes infection in human causing rheumatic heart disease. The mga gene of S. pyogenes specific 24 mer ssDNA probe was covalently immobilized on SWNT through a molecular bilinker, 1-pyrenemethylamine, using carbodiimide coupling reaction. The sensor was characterized by the current-voltage (I-V) characteristic curve and scanning electron microscopy. The sensing performance of the sensor was studied with respect to changes in conductance in SWNT channel based on hybridization of the target S. pyogenes single stranded genomic DNA (ssG-DNA) to its complementary 24 mer ssDNA probe. The sensor shows negligible response to non-complementary Staphylococcus aureus ssG-DNA, confirming the specificity of the sensor only with S. pyogenes. The genosensor exhibited a linear response to S. pyogenes G-DNA from 1 to1000 ng ml −1 with a limit of detection of 0.16 ng ml −1

  8. Single-walled carbon nanotubes based chemiresistive genosensor for label-free detection of human rheumatic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Swati; Kumar, Ashok, E-mail: rajesh-csir@yahoo.com, E-mail: ashokigib@rediffmail.com [CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007 (India); Academy of Scientific and Innovative Research (AcSIR), New Delhi (India); Khare, Shashi [National Centre for Disease Control, Sham Nath Marg, Delhi 110054 (India); Mulchandani, Ashok [Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521 (United States); Rajesh, E-mail: rajesh-csir@yahoo.com, E-mail: ashokigib@rediffmail.com [CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi 110012 (India)

    2014-11-24

    A specific and ultrasensitive, label free single-walled carbon nanotubes (SWNTs) based chemiresistive genosensor was fabricated for the early detection of Streptococcus pyogenes infection in human causing rheumatic heart disease. The mga gene of S. pyogenes specific 24 mer ssDNA probe was covalently immobilized on SWNT through a molecular bilinker, 1-pyrenemethylamine, using carbodiimide coupling reaction. The sensor was characterized by the current-voltage (I-V) characteristic curve and scanning electron microscopy. The sensing performance of the sensor was studied with respect to changes in conductance in SWNT channel based on hybridization of the target S. pyogenes single stranded genomic DNA (ssG-DNA) to its complementary 24 mer ssDNA probe. The sensor shows negligible response to non-complementary Staphylococcus aureus ssG-DNA, confirming the specificity of the sensor only with S. pyogenes. The genosensor exhibited a linear response to S. pyogenes G-DNA from 1 to1000 ng ml{sup −1} with a limit of detection of 0.16 ng ml{sup −1}.

  9. Reinforcement mechanism of multi-anchor wall with double wall facing

    Science.gov (United States)

    Suzuki, Kouta; Kobayashi, Makoto; Miura, Kinya; Konami, Takeharu; Hayashi, Taketo

    2017-10-01

    The reinforced soil wall has high seismic performance as generally known. However, the seismic behavior has not been clarified accurately yet, especially on multi-anchor wall with double wall facing. Indefinite behavior of reinforced soil wall during earthquake make us complicated in case with adopting to the abutment, because of arrangement of anchor plate as reinforcement often different according to the width of roads. In this study, a series of centrifuge model tests were carried out to investigate the reinforcement mechanism of multi anchor wall with double wall facing from the perspective of the vertical earth pressure. Several types of reinforce arrangement and rigid wall were applied in order to verify the arch function in the reinforced regions. The test results show unique behavior of vertical earth pressure, which was affected by arch action. All the vertical earth pressure placed behind facing panel, are larger than that of middle part between facing panel despite of friction between backfill and facing panel. Similar results were obtained in case using rigid wall. On the other hands, the vertical earth pressure, which were measured at the 3cm high from bottom of model container, shows larger than that of bottom. This results show the existence of arch action between double walls. In addition, it implies that the wall facing of such soil structure confined the backfill as pseudo wall, which is very reason that the multi anchor wall with double wall facing has high seismic performance.

  10. Regional myocardial oxygen consumption estimated by carbon-11 acetate and positron emission tomography before and after repetitive ischemia

    DEFF Research Database (Denmark)

    Kofoed, K F; Hansen, P R; Holm, S

    2000-01-01

    alternating with 5 minutes of reperfusion. Before and after repetitive coronary occlusions, oxygen 15 water/oxygen 15 carbon monoxide (blood flow), and 11C-acetate (oxygen consumption) PET imaging were performed. Left ventricular regional systolic wall thickening was measured with sonomicrometry. Forty......BACKGROUND: Preserved myocardial oxygen consumption estimated by carbon 11-acetate and positron emission tomography (PET) in myocardial regions with chronic but reversibly depressed contractile function in patients with ischemic heart disease have been suggested to be caused by repeated short......-five minutes after the ischemic episodes, systolic ventricular wall thickening was decreased by 90%, whereas myocardial blood flow was reduced by 21% compared with baseline values (P consumption was unaltered compared with the baseline level...

  11. Comparison of various quantization methods of segmental ventricular wall motion in ischemic heart disease

    International Nuclear Information System (INIS)

    Probst, P.; Moore, R.; Kim, S.W.; Zollikofer, C.; Amplatz, K.

    1981-01-01

    Numerous methods of measuring regional myocardial wall motion are in use. A critical comparison is needed to assess the strengths, weaknesses, accuracy, and precision of these methods. This paper reports the evaluation of five methods using computer-assisted interactive graphics. Fifty cines were selected: 16 from normal subjects, and 34 from patients with proven cardiovascular diseases. Tracings were made of the opacified left ventricle in end systole and dastole and digitized. All fifty cines were analyzed by five methods using computer-implemented graphic techniques. The reults included a display of the silhouettes, which were translated and rotated according to various methods. In addition, the percent contraction for eleven myocardial regions was tabulated and displayed. The sixteen cines from normal subjects were used to derive 1 range of 'house' normal values for region contraction patterns with which the measurements from the 34 abnormal patients were compared. The five methods were evaluated by comparing results from the computer-aided analysis with the visual assessment of two experienced radiologists. One method was found, the results from which agreed with the radiologists' visual impression for every case. This computer-aided method was quantitative and reproducible. Consequently, it can give information which supplements the visual impression. (orig.) [de

  12. Plasma-wall interactions

    International Nuclear Information System (INIS)

    Behrisch, Rainer

    1978-01-01

    The plasma wall interactions for two extreme cases, the 'vacuum model' and the 'cold gas blanket' are outlined. As a first step for understanding the plasma wall interactions the elementary interaction processes at the first wall are identified. These are energetic ion and neutral particle trapping and release, ion and neutral backscattering, ion sputtering, desorption by ions, photons and electrons and evaporation. These processes have only recently been started to be investigated in the parameter range of interest for fusion research. The few measured data and their extrapolation into regions not yet investigated are reviewed

  13. Enhanced washout of 99mTc-tetrofosmin in hypertrophic cardiomyopathy: quantitative comparisons with regional 123I-BMIPP uptake and wall thickness determined by MRI

    International Nuclear Information System (INIS)

    Thet-Thet-Lwin, Tohoru; Takeda, Jin; Wu, Yuko; Fumikura, Keiji; Iida, Satoru; Kawano, Iwao; Yamaguchi, Yuji; Itai

    2003-01-01

    The diagnostic value of technetium-99m tetrofosmin (TF) washout in hypertrophic cardiomyopathy (HCM) was examined by investigating its relation to the metabolic abnormality depicted by iodine-123 β-methyl-p-iodophenylpentadecanoic acid (BMIPP) uptake and the left ventricular (LV) myocardial wall thickness as measured by magnetic resonance imaging (MRI). TF washout was evaluated in 31 patients with HCM and 23 normal control subjects using 30-min (early) and 3-h (delayed) TF single-photon emission tomography images. The LV myocardial wall was divided into 19 segments and the percentage TF washout, regional BMIPP uptake and LV wall thickness were measured in each segment. Mean TF washout in the patients with HCM was significantly faster than that in normal control subjects (23.7±5.7 vs 13.4±4.1, P<0.0001). In the patients with HCM, TF washout showed an excellent correlation with MRI wall thickness (r=0.82, P<0.0001) and a good inverse correlation with regional BMIPP uptake (r=-0.72, P<0.0001). In addition, a good linear correlation was observed between TF uptake and MRI wall thickness in the 19 regional segments. In conclusion, the degree of TF washout corresponds well with the severity of myocardial wall thickness and the degree of metabolic abnormality in patients with HCM. These results suggest that enhanced TF washout might provide additional clinical information regarding metabolic alterations in HCM. (orig.)

  14. Enhanced washout of 99mTc-tetrofosmin in hypertrophic cardiomyopathy: quantitative comparisons with regional 123I-BMIPP uptake and wall thickness determined by MRI.

    Science.gov (United States)

    Thet-Thet-Lwin; Takeda, Tohoru; Wu, Jin; Fumikura, Yuko; Iida, Keiji; Kawano, Satoru; Yamaguchi, Iwao; Itai, Yuji

    2003-07-01

    The diagnostic value of technetium-99m tetrofosmin (TF) washout in hypertrophic cardiomyopathy (HCM) was examined by investigating its relation to the metabolic abnormality depicted by iodine-123 beta-methyl- p-iodophenylpentadecanoic acid (BMIPP) uptake and the left ventricular (LV) myocardial wall thickness as measured by magnetic resonance imaging (MRI). TF washout was evaluated in 31 patients with HCM and 23 normal control subjects using 30-min (early) and 3-h (delayed) TF single-photon emission tomography images. The LV myocardial wall was divided into 19 segments and the percentage TF washout, regional BMIPP uptake and LV wall thickness were measured in each segment. Mean TF washout in the patients with HCM was significantly faster than that in normal control subjects (23.7+/-5.7 vs 13.4+/-4.1, P<0.0001). In the patients with HCM, TF washout showed an excellent correlation with MRI wall thickness ( r=0.82, P<0.0001) and a good inverse correlation with regional BMIPP uptake ( r=-0.72, P<0.0001). In addition, a good linear correlation was observed between TF uptake and MRI wall thickness in the 19 regional segments. In conclusion, the degree of TF washout corresponds well with the severity of myocardial wall thickness and the degree of metabolic abnormality in patients with HCM. These results suggest that enhanced TF washout might provide additional clinical information regarding metabolic alterations in HCM.

  15. Identification of acute myocardial infarction with MR imaging by using combined assessment of regional wall motion and Gd-DTPA uptake

    International Nuclear Information System (INIS)

    Roos, A. de; Matheijssen, N.A.A.; Doornbos, J.; van Dijkman, P.; Pattynama, P.; van der Wall, E.

    1990-01-01

    This paper evaluates the usefulness of MR imaging for identification of acute myocardial infarction (AMI) in clinical patients, based on the assessment of regional wall motion abnormalities in conjunction with local uptake of Gd-DTPA. Fourteen patients with proved AMI and 12 normal volunteers underwent multisection-multiphase MR imaging in the short-axis plane encompassing the entire left ventricle. Gd-DTPA (0.2 mmol/kg) was injected in all patients to enhance the infarcted region. MR cine loops of the patients and volunteers were blinded and displayed. Three experienced observers scored the cine loops in consensus as to the presence or absence of AMI, noting wall motion abnormalities and/or increased Gd-DTPA uptake

  16. Wall motion abnormality of myocardial infarction

    International Nuclear Information System (INIS)

    Hayashi, Senji; Tsuda, Takashi; Ojima, Kenji

    1984-01-01

    By use of the gated blood pool scan, we divided the left ventricular LAO 45 image into 8 sections with the center of the volume as the basal point, and devised a method of quantitative evaluation of the regional wall motion from 2 aspects: 1) wall movement and 2) phase abnormality. To evaluate the wall movement, we obtained the following indeces from count curves of each section: 1) EF1=(end-diastolic count-end-systolic count)/ end-diastolic count, 2) EF2=(maximum count-minimum count)/maximum count, and 3) the difference of the two (EF2-EF1). As indeces of the phase abnormality, the mean value of phases of the pixels (phase characteristics) and the standard deviation (variation) of each section were calculated. Furthermore, the phase delay of each section was calculated as the difference from the earliest phase value of the 8 sections. Control values and standard deviation were obtained from 8 healthy controls. By this method, we analyzed 20 patients with old myocardial infarction. And following results were obtained: 1. Applying this method, we could evaluate the regional wall motion of the left ventricle more precisely, and we considered it would be useful clinically. 2. The abnormal regional wall motion of old myocardial infarction were classified into 4 typical forms as follows: 1) the wall movement decreased extremely. 2) the wall movement decreased, but no phase delay recognized. 3) the wall movement did not decrease, but phase delay was recognized. 4) the wall movement decreased, and phase delay was recognized. (author)

  17. /sup 201/Thallium scintimetry of the heart as a new method for functional assessment in coronary heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Buell, U; Strauer, B E; Hast, B; Niendorf, H P [Muenchen Univ. (F.R. Germany). Klinik und Poliklinik fuer Radiologie; Muenchen Univ. (F.R. Germany). 1. Medizinische Klinik)

    1976-05-01

    /sup 201/Tl scintimetry of the heart was used for a statistical comparison between normal people (10 individuals) and those with acute anterior wall infarcts (5 patients), anterior wall hypokinesia (5 patients) and dyskinesia (8 patients). Numerical results were obtained by a computer and depended on the relative /sup 201/Tl storage in the left ventricular myocardium (64 mm/sup 2/ area) related to mediastinal background uptake. It was found that maximal myocardial uptake, compared with mediastinal activity (about 290%) did not differ between normals and patients with coronary heart disease. Aneurysms of the anterior ventricular wall showed a reduction (with the ventricle perpendicular to the collimator) of 45.8%; in hypokinesia and acute myocardial infarcts, it was 64.2% and 64.6% respectively (normal 82.6%). /sup 201/Tl uptake in aneurysms (42.4%) approached background activity (36%) if a projection parallel to the collimator was used. /sup 201/Tl scintimetry provides a means of defining function ability of the myocardium (depending on myocardial perfusion and mass). Aneurysms and hypokinetic portions of the myocardium can be differentiated statistically from normal /sup 201/Tl uptake.

  18. Three-dimensional fluid flow phenomena in the blade end wall corner region

    Science.gov (United States)

    Hazarika, B. K.; Raj, R.; Boldman, D. R.

    1986-01-01

    Flow visualization, static and total pressure measurements, and mean velocity profile measurements with a single-sensor inclined hot wire probe, are used in a study of three-dimensional flow at a turbine blade end wall corner region for six critical axial stations along the blade chord. Three vortices are identified: (1) a horseshoe vortex near the leading edge; (2) a corner eddy between the horseshoe vortex and the corner; and (3) a vortex at the rear portion of the corner due to the corner eddy's secondary flow. Attention is given to the relative size and rate-of-spread of the vortices in the streamwise direction.

  19. Relationship between regional severity of emphysema and coronary heart disease

    International Nuclear Information System (INIS)

    Nagao, Michinobu; Sakai, Shinya; Yasuhara, Yoshifumi; Ikezoe, Junpei; Murase, Kenya; Ichiki, Taku

    2000-01-01

    We analyzed the relationship between regional severity of emphysema, which was evaluated by three-dimensional fractal analysis (3D-FA) of Technegas SPECT images, and coronary heart disease (CHD). For 22 patients with emphysema who underwent Technegas SPECT, we followed up CHD events. The follow-up period was 5.4±0.5 (mean ±SD) years. We defined the upper-lung fractal dimension (U-FD) and lower-lung fractal dimension (L-FD) obtained with 3D-FA of Technegas SPECT images as the regional severity of emphysema. FD became greater with the progression of emphysematous change. During the follow-up period, CHD events occurred in 6 (27%) of the 22 patients. The ratio of U-FD to L-FD for patients with CHD events (0.87±0.22) was significantly smaller than for patients without CHD events (1.52±0.38) (p=0.0015). These findings suggest that severer emphysema in the lower lung indicates a higher risk of CHD than that in the upper lung. (author)

  20. Parametric images evaluation of selected phases of the heart cycle with PET

    International Nuclear Information System (INIS)

    Just, U.; Will, E.; Beuthien Baumann, B.; Bredow, J.

    2002-01-01

    The standard evaluation of dynamic heart acquisitions with PET uses image data not corrected for heart wall movement. The evaluation of parametric data sets (Patlak Plot) was investigated for gated studies of selected heart phases (diastolic, systolic) and compared to the standard evaluation. Parametric images of selected heart phases have improved resolution. The values for metabolic rate are different for a ''normal'' and gated evaluation, up to 50% more for the systole compared to the normal one. (orig.)

  1. Analysis of wall-packed-bed thermal interactions

    International Nuclear Information System (INIS)

    Gorbis, Z.R.; Tillack, M.S.; Tehranian, F.; Abdou, M.A.

    1995-01-01

    One of the major issues remaining for ceramic breeder blankets involves uncertainties in heat transfer and thermomechanical interactions within the breeder and multiplier regions. Particle bed forms are considered in many reactor blanket designs for both the breeder and Be multiplier. The effective thermal conductivity of beds and the wall-bed thermal conductance are still not adequately characterized, particularly under the influence of mechanical stresses. The problem is particularly serious for the wall conductance between Be and its cladding, where the uncertainty can be greater than 50%. In this work, we describe a new model for the wall-bed conductance that treats the near-wall region as a finite-width zone. The model includes an estimate of the region porosity based on the number of contact points, and the contact area for smooth surfaces. It solves the heat conduction in a near-wall unit cell. The model is verified with existing data and used to predict the range of wall conductances expected in future simulation experiments and in reactor applications. (orig.)

  2. Precision and accuracy in CT attenuation measurement of vascular wall using region-of-interest supported by differentiation curve

    International Nuclear Information System (INIS)

    Suzuki, Shigeru; Kidouchi, Takashi; Kuwahara, Sadatoshi; Vembar, Mani; Takei, Ryoji; Yamamoto, Asako

    2012-01-01

    Objectives: To evaluate the precision and accuracy in CT attenuation measurement of vascular wall using region-of-interest (ROI) supported by differentiation curves. Study design: We used vascular models (actual attenuation value of the wall: 87 HU) with wall thicknesses of 1.5, 1.0, or 0.5 mm, filled with contrast material of 250, 348, or 436 HU. The nine vascular models were scanned with a 64-detector CT. The wall attenuation values were measured using three sizes (diameter: 0.5, 1.0, and 1.5 mm) of ROIs without differentiation curves. Sixteen measurements were repeated for each vascular model by each of two operators. Measurements supported by differentiation curves were also performed. We used analyses of variance with repeated measures for the measured attenuations for each size of the ROI. Results: Without differentiation curves, there were significant differences in the attenuation values of the wall among the three densities of contrast material, and the attenuation values tended to be overestimated more as the contrast material density increased. Operator dependencies were also found in measurements for 0.5- and 1.5-mm thickness models. With differentiation curves, measurements were not possible for 0.5- and 1.0-mm thickness models. Using differentiation curves for 1.5-mm thickness models with a ROI of 1.0- or 1.5-mm diameter, the wall attenuations were not affected by the contrast material densities and were operator independent, measuring between 75 and 103 HU. Conclusions: The use of differentiation curves can improve the precision and accuracy in wall attenuation measurement using a ROI technique, while measurements for walls of ≤1.0 mm thickness are difficult.

  3. The septal bulge--an early echocardiographic sign in hypertensive heart disease.

    Science.gov (United States)

    Gaudron, Philipp Daniel; Liu, Dan; Scholz, Friederike; Hu, Kai; Florescu, Christiane; Herrmann, Sebastian; Bijnens, Bart; Ertl, Georg; Störk, Stefan; Weidemann, Frank

    2016-01-01

    Patients in the early stage of hypertensive heart disease tend to have normal echocardiographic findings. The aim of this study was to investigate whether pathology-specific echocardiographic morphologic and functional parameters can help to detect subclinical hypertensive heart disease. One hundred ten consecutive patients without a history and medication for arterial hypertension (AH) or other cardiac diseases were enrolled. Standard echocardiography and two-dimensional speckle-tracking-imaging analysis were performed. Resting blood pressure (BP) measurement, cycle ergometer test (CET), and 24-hour ambulatory BP monitoring (ABPM) were conducted. Patients were referred to "septal bulge (SB)" group (basal-septal wall thickness ≥ 2 mm thicker than mid-septal wall thickness) or "no-SB" group. Echocardiographic SB was found in 48 (43.6%) of 110 patients. In this SB group, 38 (79.2%) patients showed AH either by CET or ABPM. In contrast, in the no-SB group (n = 62), 59 (95.2%) patients had no positive test for AH by CET or ABPM. When AH was solely defined by resting BP, SB was a reasonable predictive sign for AH (sensitivity 73%, specificity 76%). However, when AH was confirmed by CET or ABPM the echocardiographic SB strongly predicted clinical AH (sensitivity 93%, specificity 86%). In addition, regional myocardial deformation of the basal-septum in SB group was significantly lower than in no-SB group (14 ± 4% vs. 17 ± 4%; P heart disease. Sophisticated BP evaluation including resting BP, ABPM, and CET should be performed in all patients with an accidental finding of a SB in echocardiography. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Proton nuclear magnetic resonance imaging of regionally ischemic canine hearts: effects of paramagnetic proton signal enhancement

    International Nuclear Information System (INIS)

    Brady, T.J.; Goldman, M.R.; Pykett, I.L.; Buonanno, F.S.; Kistler, J.P.; Newhouse, J.H.; Burt, C.T.; Hinshaw, W.S.; Pohost, G.M.

    1982-01-01

    In a study to evaluate the potential of proton nuclear magnetic resonance (NMR) imaging with and without manganese contrast enhancement for detecting acute myocardial infarction, 12 dogs underwent 90-minute occlusion of the left circumflex coronary artery. Transverse-section NMR images of the excised, nonbeating heart were obtained at 1-cm intervals using the steady-state-free-precession (SSFP) technique. All NMR images revealed detailed structure of the heart. The three hearts without manganese showed no difference in intensity between the normal and the ischemic posterior regions, whereas those with manganese demonstrated a clearly demarcated zone of reduced signal intensity consistent with the ischemic zone. It is concluded that high-resolution tomograms of the excised canine myocardium can be obtained using proton NMR imaging. With the SSFP imaging technique, proton signal enhancement with manganese infusion is necessary to differentiate between ischemic and nonischemic myocardium after 90 minutes of coronary occlusion

  5. Association between Functional Variables and Heart Failure after Myocardial Infarction in Rats

    Energy Technology Data Exchange (ETDEWEB)

    Polegato, Bertha F.; Minicucci, Marcos F.; Azevedo, Paula S.; Gonçalves, Andréa F.; Lima, Aline F.; Martinez, Paula F.; Okoshi, Marina P.; Okoshi, Katashi; Paiva, Sergio A. R.; Zornoff, Leonardo A. M., E-mail: lzornoff@fmb.unesp.br [Faculdade de Medicina de Botucatu - Universidade Estadual Paulista ' Júlio de mesquita Filho' - UNESP Botucatu, SP (Brazil)

    2016-02-15

    Heart failure prediction after acute myocardial infarction may have important clinical implications. To analyze the functional echocardiographic variables associated with heart failure in an infarction model in rats. The animals were divided into two groups: control and infarction. Subsequently, the infarcted animals were divided into groups: with and without heart failure. The predictive values were assessed by logistic regression. The cutoff values predictive of heart failure were determined using ROC curves. Six months after surgery, 88 infarcted animals and 43 control animals were included in the study. Myocardial infarction increased left cavity diameters and the mass and wall thickness of the left ventricle. Additionally, myocardial infarction resulted in systolic and diastolic dysfunction, characterized by lower area variation fraction values, posterior wall shortening velocity, E-wave deceleration time, associated with higher values of E / A ratio and isovolumic relaxation time adjusted by heart rate. Among the infarcted animals, 54 (61%) developed heart failure. Rats with heart failure have higher left cavity mass index and diameter, associated with worsening of functional variables. The area variation fraction, the E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate were functional variables predictors of heart failure. The cutoff values of functional variables associated with heart failure were: area variation fraction < 31.18%; E / A > 3.077; E-wave deceleration time < 42.11 and isovolumic relaxation time adjusted by heart rate < 69.08. In rats followed for 6 months after myocardial infarction, the area variation fraction, E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate are predictors of heart failure onset.

  6. Association between Functional Variables and Heart Failure after Myocardial Infarction in Rats

    International Nuclear Information System (INIS)

    Polegato, Bertha F.; Minicucci, Marcos F.; Azevedo, Paula S.; Gonçalves, Andréa F.; Lima, Aline F.; Martinez, Paula F.; Okoshi, Marina P.; Okoshi, Katashi; Paiva, Sergio A. R.; Zornoff, Leonardo A. M.

    2016-01-01

    Heart failure prediction after acute myocardial infarction may have important clinical implications. To analyze the functional echocardiographic variables associated with heart failure in an infarction model in rats. The animals were divided into two groups: control and infarction. Subsequently, the infarcted animals were divided into groups: with and without heart failure. The predictive values were assessed by logistic regression. The cutoff values predictive of heart failure were determined using ROC curves. Six months after surgery, 88 infarcted animals and 43 control animals were included in the study. Myocardial infarction increased left cavity diameters and the mass and wall thickness of the left ventricle. Additionally, myocardial infarction resulted in systolic and diastolic dysfunction, characterized by lower area variation fraction values, posterior wall shortening velocity, E-wave deceleration time, associated with higher values of E / A ratio and isovolumic relaxation time adjusted by heart rate. Among the infarcted animals, 54 (61%) developed heart failure. Rats with heart failure have higher left cavity mass index and diameter, associated with worsening of functional variables. The area variation fraction, the E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate were functional variables predictors of heart failure. The cutoff values of functional variables associated with heart failure were: area variation fraction < 31.18%; E / A > 3.077; E-wave deceleration time < 42.11 and isovolumic relaxation time adjusted by heart rate < 69.08. In rats followed for 6 months after myocardial infarction, the area variation fraction, E/A ratio, E-wave deceleration time and isovolumic relaxation time adjusted by heart rate are predictors of heart failure onset

  7. Biodistribution of radioactive organocations and cationic technetium complexes - implications to the uptake mechanism of potential heart-affine radiopharmaceuticals

    International Nuclear Information System (INIS)

    Muenze, R.; Shyre, R.; Seifert, S.; Guethert, I.; Kretschmar, M.; Kampf, G.; Knop, G.; Mohnike, W.; Schmidt, J.

    1986-01-01

    The biodistribution of various 14 C labeled organocations (ammonium, phosphonium) and cationic technetium complexes (TcCl 2 DMPE 2 ,TcDMPE 3 + ) was studied in rats to find potential relations between the chemical composition, structure, molecular size, lipophilicity and heart uptake. All of the radioactive cations were distributed in a similar manner, but with different biokinetics. Molecules containing several electronegative atoms in their ligand structure, e.g. nitrogen or oxygen which enhance polarity, were rapidly accumulated, but washed out again with resultant transient and diminished heart uptake. More highly lipophilic materials, by contrast, showed more extensive accumulation and persistent retention in the heart. The effect of human serum albumin on heart uptake was studied in a perfused heart model. Strong albumin binding prevented extensive heart uptake. This undesirable effect was neutralized by adding detergents to the perfusion bath. Evidence from these animal experiments was considered in the development of a new heart-seeking technetium compound (Tc-DPO), which is characterized by rapid accumulation in the human heart and substantially delayed washout. Heart images with minimal overlap of the inferoposterior wall and the right liver lobe were available in no more than 10 minutes p.i. in both planar and SPECT modes. A deficit in the inferior region was much more clearly defined than on the corresponding Thallium image. (Author)

  8. Myocardium scanning with 201TL-chloride in ischemic heart disease

    International Nuclear Information System (INIS)

    Shejretova, E.; Beloev, J.; Kaloyanova, A.; Trindev, P.

    1979-01-01

    Results of myocardial scanning with 210 TL-chloride in ischemic herart disease are repoorted. An avearge dose of 500 microcurie and antero-posterior or lateral projection scanning with coloured registration are recommended. The scintigraphic pattern of the normal myocardium and the pathological changes, manifested by reduced isotope fixation, depending on the severity of the damage, are described. The diffuse pathological changes in the myocardium in ischemic heart disease are manifested by diffuse hypofixation of the radionuclide. The focal lesions in ischemic heart disease were manifested by characteristic changes: the infarctions of the posterior wall show a relatively clear scanographic picture on antero-posterior projection, with cold or cool zones in the median sections of the myocardium picture. Infarctions of the anterior myocardial wall, depending on how sizable they are, on antero-posterior projection are seen to occupy the lateral and central parts of the heart muscle. In the left oblique projection the pathologic process is projected frontally and centrally. (A.B.)

  9. Differential Lectin Binding Patterns Identify Distinct Heart Regions in Giant Danio (Devario aequipinnatus) and Zebrafish (Danio rerio) Hearts

    Science.gov (United States)

    Manalo, Trina; May, Adam; Quinn, Joshua; Lafontant, Dominique S.; Shifatu, Olubusola; He, Wei; Gonzalez-Rosa, Juan M.; Burns, Geoffrey C.; Burns, Caroline E.; Burns, Alan R.; Lafontant, Pascal J.

    2016-01-01

    Lectins are carbohydrate-binding proteins commonly used as biochemical and histochemical tools to study glycoconjugate (glycoproteins, glycolipids) expression patterns in cells, tissues, including mammalian hearts. However, lectins have received little attention in zebrafish (Danio rerio) and giant danio (Devario aequipinnatus) heart studies. Here, we sought to determine the binding patterns of six commonly used lectins—wheat germ agglutinin (WGA), Ulex europaeus agglutinin, Bandeiraea simplicifolia lectin (BS lectin), concanavalin A (Con A), Ricinus communis agglutinin I (RCA I), and Lycopersicon esculentum agglutinin (tomato lectin)—in these hearts. Con A showed broad staining in the myocardium. WGA stained cardiac myocyte borders, with binding markedly stronger in the compact heart and bulbus. BS lectin, which stained giant danio coronaries, was used to measure vascular reconstruction during regeneration. However, BS lectin reacted poorly in zebrafish. RCA I stained the compact heart of both fish. Tomato lectin stained the giant danio, and while low reactivity was seen in the zebrafish ventricle, staining was observed in their transitional cardiac myocytes. In addition, we observed unique staining patterns in the developing zebrafish heart. Lectins’ ability to reveal differential glycoconjugate expression in giant danio and zebrafish hearts suggests they can serve as simple but important tools in studies of developing, adult, and regenerating fish hearts. PMID:27680670

  10. Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Fujino, Takayuki; Ishii, Yoshinao; Hirasawa, Kunihiko; Tateda, Kunihiko [Asahikawa City Hospital, Hokkaido (Japan); Takeuchi, Toshiharu; Kikuchi, Kenjiro; Hasebe, Naoyuki [Asahikawa Medical Coll., Hokkaido (Japan)

    2003-09-01

    The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-{beta}-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The IR, estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion. (author)

  11. Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction

    International Nuclear Information System (INIS)

    Fujino, Takayuki; Ishii, Yoshinao; Hirasawa, Kunihiko; Tateda, Kunihiko; Takeuchi, Toshiharu; Kikuchi, Kenjiro; Hasebe, Naoyuki

    2003-01-01

    The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-β-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The IR, estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion. (author)

  12. Recovery of BMIPP uptake and regional wall motion in insulin resistant patients following angioplasty for acute myocardial infarction.

    Science.gov (United States)

    Fujino, Takayuki; Ishii, Yoshinao; Takeuchi, Toshiharu; Hirasawa, Kunihiko; Tateda, Kunihiko; Kikuchi, Kenjiro; Hasebe, Naoyuki

    2003-09-01

    The effect of insulin resistance (IR) on the fatty acid metabolism of myocardium, and therefore on the recovery of left ventricular (LV) wall motion, has not been established in patients with acute myocardial infarction (AMI). A total of consecutive 58 non-diabetic AMI patients who had successfully undergone emergency coronary angioplasty were analyzed retrospectively. They were categorized into 2 groups, normal glucose tolerance (NGT) and impaired glucose tolerance (IGT), based on a 75-g oral glucose tolerance test (OGTT). The parameters of OGTT, myocardial scintigraphy (n=58) (thallium-201 (Tl) and iodine-123-beta-methyl-iodophenylpentadecanoic acid (BMIPP)) and left ventriculography (n=24) were compared in the 2 groups after reperfusion (acute phase) and 3-4 weeks after the AMI (chronic phase). The insulin resistance (IR), estimated by the serum concentration of insulin at 120 min (IRI 120') of the OGTT and by the HOMA (the homeostasis model assessment) index, was higher in the IGT group than in NGT group. An inverse correlation was found between the recovery of regional LV wall motion in the ischemic lesion and the IRI 120' and HOMA index. Although the recovery of BMIPP uptake from the acute to the chronic phase was higher in the IGT group, it was only correlated with the degree of IRI 120', not with the HOMA. IR accompanied by IGT can negatively influence the recovery of regional LV wall motion.

  13. Enhanced washout of {sup 99m}Tc-tetrofosmin in hypertrophic cardiomyopathy: quantitative comparisons with regional {sup 123}I-BMIPP uptake and wall thickness determined by MRI

    Energy Technology Data Exchange (ETDEWEB)

    Thet-Thet-Lwin, Tohoru; Takeda, Jin; Wu, Yuko; Fumikura, Keiji; Iida, Satoru; Kawano, Iwao; Yamaguchi, Yuji; Itai [Institute of Clinical Medicine, University of Tsukuba, Tennodai 1-1-1, 305-8575, Tsukuba-shi, Ibaraki-ken (Japan)

    2003-07-01

    The diagnostic value of technetium-99m tetrofosmin (TF) washout in hypertrophic cardiomyopathy (HCM) was examined by investigating its relation to the metabolic abnormality depicted by iodine-123 {beta}-methyl-p-iodophenylpentadecanoic acid (BMIPP) uptake and the left ventricular (LV) myocardial wall thickness as measured by magnetic resonance imaging (MRI). TF washout was evaluated in 31 patients with HCM and 23 normal control subjects using 30-min (early) and 3-h (delayed) TF single-photon emission tomography images. The LV myocardial wall was divided into 19 segments and the percentage TF washout, regional BMIPP uptake and LV wall thickness were measured in each segment. Mean TF washout in the patients with HCM was significantly faster than that in normal control subjects (23.7{+-}5.7 vs 13.4{+-}4.1, P<0.0001). In the patients with HCM, TF washout showed an excellent correlation with MRI wall thickness (r=0.82, P<0.0001) and a good inverse correlation with regional BMIPP uptake (r=-0.72, P<0.0001). In addition, a good linear correlation was observed between TF uptake and MRI wall thickness in the 19 regional segments. In conclusion, the degree of TF washout corresponds well with the severity of myocardial wall thickness and the degree of metabolic abnormality in patients with HCM. These results suggest that enhanced TF washout might provide additional clinical information regarding metabolic alterations in HCM. (orig.)

  14. Cardiac magnetic resonance imaging in heart failure: where the alphabet begins!

    Science.gov (United States)

    Aljizeeri, Ahmed; Sulaiman, Abdulbaset; Alhulaimi, Naji; Alsaileek, Ahmed; Al-Mallah, Mouaz H

    2017-07-01

    Cardiac Magnetic Resonance Imaging has become a cornerstone in the evaluation of heart failure. It provides a comprehensive evaluation by answering all the pertinent clinical questions across the full pathological spectrum of heart failure. Nowadays, CMR is considered the gold standard in evaluation of ventricular volumes, wall motion and systolic function. Through its unique ability of tissue characterization, it provides incremental diagnostic and prognostic information and thus has emerged as a comprehensive imaging modality in heart failure. This review outlines the role of main conventional CMR sequences in the evaluation of heart failure and their impact in the management and prognosis.

  15. The adaption growth of the heart in the higher age

    International Nuclear Information System (INIS)

    Kranz, D.; Kunde, D.; Fuhrmann, I.

    1976-01-01

    There was examined the influence of the age on the development of a compensatory hypertrophy of the heart in 4 to 16 month old masculin Wistar-rats autoradiographically. The valuation took place at various times after stenosing of the aorta and application of 3 H-thymidine separatly on both ventricular walls by counting of the nuclei of the marked muscle- and connective tissue cells of the heart and their mitosis. The 3 H-thymidine and mitotic index were calculated for the connective tissue cells and body and heart weight were determined. (author)

  16. Description, evaluation and clinical decision making according to various fetal heart rate patterns. Inter-observer and regional variability

    DEFF Research Database (Denmark)

    Lidegaard, O; Bøttcher, L M; Weber, Tom

    1992-01-01

    departments, especially between departments far apart. It is concluded that we still need a scientific clarification of which specific heart rate changes are the best predictors of fetal stress. Artificial intelligence programs for interpreting fetal cardiotocograms and ECG signals constitute one promising......At 10 Danish obstetrical departments, 116 residents (42 senior and 74 junior) participated in a study to assess inter-observer and regional variability in the description and evaluation of and clinical decision regarding 11 fetal heart rate patterns. The 11 traces included normal as well...... as pathological patterns, and normal as well as clinically asphyxiated babies. Five antepartum and six intrapartum patterns were included. A total of 1,276 descriptions and evaluations were obtained. The degree of agreement in description of fetal heart rate changes was high regarding the baseline...

  17. Right ventricular longitudinal strain correlates well with right ventricular stroke work index in patients with advanced heart failure referred for heart transplantation.

    Science.gov (United States)

    Cameli, Matteo; Lisi, Matteo; Righini, Francesca Maria; Tsioulpas, Charilaos; Bernazzali, Sonia; Maccherini, Massimo; Sani, Guido; Ballo, Piercarlo; Galderisi, Maurizio; Mondillo, Sergio

    2012-03-01

    Right ventricular (RV) systolic function has a critical role in determining the clinical outcome and success of using left ventricular assist devices (LVADs) in patients with refractory heart failure. Tissue Doppler and M-mode measurements of tricuspid systolic motion (tricuspid S' and tricuspid annular plane systolic excursion [TAPSE]) are the most currently used methods for the quantification of RV longitudinal function; RV deformation analysis by speckle-tracking echocardiography (STE) has recently allowed the analysis of global RV longitudinal function. Using cardiac catheterization as the reference standard, this study aimed at exploring the correlation between RV longitudinal function by STE and RV stroke work index (RVSWI) in patients referred for cardiac transplantation. Right-side heart catheterization and transthoracic echo Doppler were simultaneously performed in 41 patients referred for cardiac transplantation evaluation for advanced systolic heart failure. Thermodilution RV stroke volume and invasive pulmonary pressures were used to obtain RVSWI. RV longitudinal strain (RVLS) by STE was assessed averaging all segments in apical 4-chamber view (global RVLS) and by averaging RV free-wall segments (free-wall RVLS). Tricuspid S' and TAPSE were also calculated. No significant correlations were found for TAPSE or tricuspid S' with RVSWI (r = 0.14; r = 0.06; respectively). Close negative correlations between global RVLS and free-wall RVLS with the RVSWI were found (r = -0.75; r = -0.82; respectively; both P rights reserved.

  18. Dynamic positional fate map of the primary heart-forming region.

    Science.gov (United States)

    Cui, Cheng; Cheuvront, Tracey J; Lansford, Rusty D; Moreno-Rodriguez, Ricardo A; Schultheiss, Thomas M; Rongish, Brenda J

    2009-08-15

    Here we show the temporal-spatial orchestration of early heart morphogenesis at cellular level resolution, in vivo, and reconcile conflicting positional fate mapping data regarding the primary heart-forming field(s). We determined the positional fates of precardiac cells using a precision electroporation approach in combination with wide-field time-lapse microscopy in the quail embryo, a warm-blooded vertebrate (HH Stages 4 through 10). Contrary to previous studies, the results demonstrate the existence of a "continuous" circle-shaped heart field that spans the midline, appearing at HH Stage 4, which then expands to form a wide arc of progenitors at HH Stages 5-7. Our time-resolved image data show that a subset of these cardiac progenitor cells do not overlap with the expression of common cardiogenic factors, Nkx-2.5 and Bmp-2, until HH Stage 10, when a tubular heart has formed, calling into question when cardiac fate is specified and by which key factors. Sub-groups and anatomical bands (cohorts) of heart precursor cells dramatically change their relative positions in a process largely driven by endodermal folding and other large-scale tissue deformations. Thus, our novel dynamic positional fate maps resolve the origin of cardiac progenitor cells in amniotes. The data also establish the concept that tissue motion contributes significantly to cellular position fate - i.e., much of the cellular displacement that occurs during assembly of a midline heart tube (HH Stage 9) is NOT due to "migration" (autonomous motility), a commonly held belief. Computational analysis of our time-resolved data lays the foundation for more precise analyses of how cardiac gene regulatory networks correlate with early heart tissue morphogenesis in birds and mammals.

  19. A caudal proliferating growth center contributes to both poles of the forming heart tube

    NARCIS (Netherlands)

    van den Berg, G.; Abu-Issa, R.; de Boer, B.A.; Hutson, M.R.; de Boer, P.A.J.; Soufan, A.T.; Ruijter, J.M.; Kirby, M.L.; van den Hoff, M.J.B.; Moorman, A.F.M.

    2009-01-01

    Recent studies have shown that the primary heart tube continues to grow by addition of cells from the coelomic wall. This growth occurs concomitantly with embryonic folding and formation of the coelomic cavity, making early heart formation morphologically complex. A scarcity of data on localized

  20. Fluorine-18 heart dosimetry in myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Toledo, Janine M.; Trindade, Bruno; Campos, Tarcísio P.R., E-mail: janine.toledo@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pós-Graduação em Ciências e Técnicas Nucleares

    2017-07-01

    This paper conducts a recalling in myocardial perfusion imaging (MPI) followed by a spatial dosimetric investigation of the Fluorine-18 distributed at the myocardium by self-absorption of the heart uptake. Methods and Results: Radiological data manipulation was prepared and a computational heart voxelized model was assembled. A set of images from the abdominal aorta and angiotomography of the thorax was set up providing anatomic and functional information for heart modeling in SISCODES code. A homogeneous distribution of fluorine-18 was assumed into the heart myocardial wall. MCNP – Monte Carlo Code was used to provide the photon transport into the heart model taken in consideration the interactions into the tissues. The spatial dose distribution and histogram dose versus volume are presented. An analytical alternative model was addressed to the data validation. The present developed tools can produce spatial dose distribution in MPI at heart. Specially, the dosimetry performed elucidates imparted dose in the myocardial muscle per unit of injected Fluorine-18 activity by self-absorption of the heart uptake, which can contribute to future deterministic effect investigations. (author)

  1. Fluorine-18 heart dosimetry in myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Toledo, Janine M.; Trindade, Bruno; Campos, Tarcísio P.R.

    2017-01-01

    This paper conducts a recalling in myocardial perfusion imaging (MPI) followed by a spatial dosimetric investigation of the Fluorine-18 distributed at the myocardium by self-absorption of the heart uptake. Methods and Results: Radiological data manipulation was prepared and a computational heart voxelized model was assembled. A set of images from the abdominal aorta and angiotomography of the thorax was set up providing anatomic and functional information for heart modeling in SISCODES code. A homogeneous distribution of fluorine-18 was assumed into the heart myocardial wall. MCNP – Monte Carlo Code was used to provide the photon transport into the heart model taken in consideration the interactions into the tissues. The spatial dose distribution and histogram dose versus volume are presented. An analytical alternative model was addressed to the data validation. The present developed tools can produce spatial dose distribution in MPI at heart. Specially, the dosimetry performed elucidates imparted dose in the myocardial muscle per unit of injected Fluorine-18 activity by self-absorption of the heart uptake, which can contribute to future deterministic effect investigations. (author)

  2. 3D cardiac wall thickening assessment for acute myocardial infarction

    Science.gov (United States)

    Khalid, A.; Chan, B. T.; Lim, E.; Liew, Y. M.

    2017-06-01

    Acute myocardial infarction (AMI) is the most severe form of coronary artery disease leading to localized myocardial injury and therefore irregularities in the cardiac wall contractility. Studies have found very limited differences in global indices (such as ejection fraction, myocardial mass and volume) between healthy subjects and AMI patients, and therefore suggested regional assessment. Regional index, specifically cardiac wall thickness (WT) and thickening is closely related to cardiac function and could reveal regional abnormality due to AMI. In this study, we developed a 3D wall thickening assessment method to identify regional wall contractility dysfunction due to localized myocardial injury from infarction. Wall thickness and thickening were assessed from 3D personalized cardiac models reconstructed from cine MRI images by fitting inscribed sphere between endocardial and epicardial wall. The thickening analysis was performed in 5 patients and 3 healthy subjects and the results were compared against the gold standard 2D late-gadolinium-enhanced (LGE) images for infarct localization. The notable finding of this study is the highly accurate estimation and visual representation of the infarct size and location in 3D. This study provides clinicians with an intuitive way to visually and qualitatively assess regional cardiac wall dysfunction due to infarction in AMI patients.

  3. The pathophysiology of heart failure.

    Science.gov (United States)

    Kemp, Clinton D; Conte, John V

    2012-01-01

    Heart failure is a clinical syndrome that results when the heart is unable to provide sufficient blood flow to meet metabolic requirements or accommodate systemic venous return. This common condition affects over 5 million people in the United States at a cost of $10-38 billion per year. Heart failure results from injury to the myocardium from a variety of causes including ischemic heart disease, hypertension, and diabetes. Less common etiologies include cardiomyopathies, valvular disease, myocarditis, infections, systemic toxins, and cardiotoxic drugs. As the heart fails, patients develop symptoms which include dyspnea from pulmonary congestion, and peripheral edema and ascites from impaired venous return. Constitutional symptoms such as nausea, lack of appetite, and fatigue are also common. There are several compensatory mechanisms that occur as the failing heart attempts to maintain adequate function. These include increasing cardiac output via the Frank-Starling mechanism, increasing ventricular volume and wall thickness through ventricular remodeling, and maintaining tissue perfusion with augmented mean arterial pressure through activation of neurohormonal systems. Although initially beneficial in the early stages of heart failure, all of these compensatory mechanisms eventually lead to a vicious cycle of worsening heart failure. Treatment strategies have been developed based upon the understanding of these compensatory mechanisms. Medical therapy includes diuresis, suppression of the overactive neurohormonal systems, and augmentation of contractility. Surgical options include ventricular resynchronization therapy, surgical ventricular remodeling, ventricular assist device implantation, and heart transplantation. Despite significant understanding of the underlying pathophysiological mechanisms in heart failure, this disease causes significant morbidity and carries a 50% 5-year mortality. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Higher coronary heart disease and heart attack morbidity in Appalachian coal mining regions.

    Science.gov (United States)

    Hendryx, Michael; Zullig, Keith J

    2009-11-01

    This study analyzes the U.S. 2006 Behavioral Risk Factor Surveillance System survey data (N=235,783) to test whether self-reported cardiovascular disease rates are higher in Appalachian coal mining counties compared to other counties after control for other risks. Dependent variables include self-reported measures of ever (1) being diagnosed with cardiovascular disease (CVD) or with a specific form of CVD including (2) stroke, (3) heart attack, or (4) angina or coronary heart disease (CHD). Independent variables included coal mining, smoking, BMI, drinking, physician supply, diabetes co-morbidity, age, race/ethnicity, education, income, and others. SUDAAN Multilog models were estimated, and odds ratios tested for coal mining effects. After control for covariates, people in Appalachian coal mining areas reported significantly higher risk of CVD (OR=1.22, 95% CI=1.14-1.30), angina or CHD (OR=1.29, 95% CI=1.19-1.39) and heart attack (OR=1.19, 95% CI=1.10-1.30). Effects were present for both men and women. Cardiovascular diseases have been linked to both air and water contamination in ways consistent with toxicants found in coal and coal processing. Future research is indicated to assess air and water quality in coal mining communities in Appalachia, with corresponding environmental programs and standards established as indicated.

  5. Presence of post-systolic shortening is an independent predictor of heart failure in patients following ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Brainin, Philip; Haahr-Pedersen, Sune; Sengeløv, Morten

    2018-01-01

    echocardiography (STE) in six myocardial walls from all three apical projections. During a median follow-up period of 5.4 years (interquartile range, 4.1-6.0 years), 180 events occurred: 59 deaths, 70 heart failures (HF) and 51 new myocardial infarctions (MI). In multivariable analysis adjusting for: age, sex......Following an ischemic event post systolic shortening (PSS) may occur. We investigated the association between PSS in patients with ST-segment elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (pPCI) and occurrence of cardiovascular events at follow...... incrementally with increasing numbers of walls displaying PSS. The increased risk of HF was confirmed when assessing the post-systolic index by STE (HR 1.29 95% CI 1.09-1.53, P = 0.003, per 1% increase). A regional analysis showed that PSS by TDI in the septal wall was the strongest predictor of HF (HR 1.77, 95...

  6. Computer-aided detection of bladder wall thickening in CT urography (CTU)

    Science.gov (United States)

    Cha, Kenny H.; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Caoili, Elaine M.; Cohan, Richard H.; Weizer, Alon Z.; Gordon, Marshall N.; Samala, Ravi K.

    2018-02-01

    We are developing a computer-aided detection system for bladder cancer in CT urography (CTU). Bladder wall thickening is a manifestation of bladder cancer and its detection is more challenging than the detection of bladder masses. We first segmented the inner and outer bladder walls using our method that combined deep-learning convolutional neural network with level sets. The non-contrast-enhanced region was separated from the contrast-enhanced region with a maximum-intensity-projection-based method. The non-contrast region was smoothed and gray level threshold was applied to the contrast and non-contrast regions separately to extract the bladder wall and potential lesions. The bladder wall was transformed into a straightened thickness profile, which was analyzed to identify regions of wall thickening candidates. Volume-based features of the wall thickening candidates were analyzed with linear discriminant analysis (LDA) to differentiate bladder wall thickenings from false positives. A data set of 112 patients, 87 with wall thickening and 25 with normal bladders, was collected retrospectively with IRB approval, and split into independent training and test sets. Of the 57 training cases, 44 had bladder wall thickening and 13 were normal. Of the 55 test cases, 43 had wall thickening and 12 were normal. The LDA classifier was trained with the training set and evaluated with the test set. FROC analysis showed that the system achieved sensitivities of 93.2% and 88.4% for the training and test sets, respectively, at 0.5 FPs/case.

  7. Myocardial imaging with 99mTc-Tetrofosmin: Influence of post-stress acquisition time, regional radiotracer uptake, and wall motion abnormalities on the clinical result.

    Science.gov (United States)

    Giorgetti, Assuero; Kusch, Annette; Casagranda, Mirta; Tagliavia, Irene D'Aragona; Marzullo, Paolo

    2010-04-01

    We previously demonstrated that early (15', T1) post-stress myocardial imaging with Tetrofosmin could be more accurate than standard acquisitions (45', T2) in identifying coronary artery disease. To clarify this phenomenon, 120 subjects (age 61 +/- 10 years) with both T1 and T2 scans were divided into Group 1 (53/120 pts) with more ischemia at T1 vs T2 imaging (T1-T2SDS > or = 3); Group 2 (67/120 pts) with similar results (T1-T2SDS statistic and semiquantitative wall motion/thickening values were obtained. Analysis of T1 and T2 post-stress myocardial counts demonstrated a significant Tetrofosmin wash-out rate that was higher in Group 1 control nonischemic regions (15 +/- 8% vs 13.6 +/- 9.6%, P stress wall thickening (T1-T2) was lower in Group 1 ischemic regions (-4.5 +/- 9.15% vs -1.90 +/- 7.0%, P stress acquisition time because of ischemic-induced regional wall thickening abnormalities and the existence of a differential radiotracer myocardial wash-out.

  8. Direct numerical simulation of MHD flow with electrically conducting wall

    International Nuclear Information System (INIS)

    Satake, S.; Kunugi, T.; Naito, N.; Sagara, A.

    2006-01-01

    The 2D vortex problem and 3D turbulent channel flow are treated numerically to assess the effect of electrically conducting walls on turbulent MHD flow. As a first approximation, the twin vortex pair is considered as a model of a turbulent eddy near the wall. As the eddy approaches and collides with the wall, a high value electrical potential is induced inside the wall. The Lorentz force, associated with the potential distribution, reduces the velocity gradient in the near-wall region. When considering a fully developed turbulent channel flow, a high electrical conductivity wall was chosen to emphasize the effect of electromagnetic coupling between the wall and the flow. The analysis was performed using DNS. The results are compared with a non-MHD flow and MHD flow in the insulated channel. The mean velocity within the logarithmic region in the case of the electrically conducting wall is slightly higher than that in the non-conducting wall case. Thus, the drag is smaller compared to that in the non-conducting wall case due to a reduction of the Reynolds stress in the near wall region through the Lorentz force. This mechanism is explained via reduction of the production term in the Reynolds shear stress budget

  9. Blood pressure, risk of ischemic cerebrovascular and ischemic heart disease, and longevity in alpha(1)-antitrypsin deficiency

    DEFF Research Database (Denmark)

    Dahl, Morten; Tybjaerg-Hansen, Anne; Sillesen, Henrik

    2003-01-01

    Because elastase in alpha(1)-antitrypsin deficiency may attack elastin in the arterial wall, we tested whether alpha(1)-antitrypsin deficiency is associated with reduced blood pressure, risk of ischemic cerebrovascular (ICVD) and ischemic heart disease (IHD), and longevity.......Because elastase in alpha(1)-antitrypsin deficiency may attack elastin in the arterial wall, we tested whether alpha(1)-antitrypsin deficiency is associated with reduced blood pressure, risk of ischemic cerebrovascular (ICVD) and ischemic heart disease (IHD), and longevity....

  10. Rare occurrence of heart lesions in Pacific oysters Crassostrea gigas caused by an unknown bacterial infection.

    Science.gov (United States)

    Meyer, Gary R; Lowe, Geoffrey J; Bower, Susan M

    2017-09-20

    On rare occasions, small cream-coloured cysts have been observed in the heart and pericardial cavity of Pacific oysters Crassostrea gigas from British Columbia, Canada. Histopathology revealed the presence of large colonies of bacteria (up to 800 µm in diameter) causing significant host response and hypertrophy of the heart epithelium. The causative bacteria were characterized as follows: Gram-negative, coccoid to small rod-shaped, typically <1.5 µm in size, cell walls highly endowed with surface fimbriae and division via binary fission. Although these bacteria shared some morphological characteristics with the order Rickettsiales, they did not require an intracellular existence for multiplication. Unfortunately, a cultured isolate was not available, and a retrospective attempt to further characterize the bacteria using DNA sequence analysis of a fragment from the 16S rDNA region proved to be uninformative.

  11. Myocardial imaging in the noninvasive evaluation of patients with suspected ischemic heart disease

    International Nuclear Information System (INIS)

    Pitt, B.; Strauss, H.W.

    1976-01-01

    Three noninvasive radioactive tracer techniques for evaluating patients with ischemic heart disease are described: (1) myocardial perfusion imaging, (2) acute infarct imaging, and (3) the gated blood pool scan. Myocardial perfusion imaging with tracers that distribute in the myocardium in relation to regional blood flow allows detection of patients with transmural and nontransmural infarction by the finding of decreased tracer concentration in the affected region of the myocardium. If these tracers are injected at the time of maximal stress to patients with significant coronary arterial stenosis but without infarction, areas of transient ischemia can be identified as zones of decreased tracer concentration not found when an examination is performed at rest. Acute infarct imaging with tracers that localize in acutely damaged tissue permits separation of patients with acute myocardial necrosis from those without infarction and those with more chronic damage. The gated blood pool scan permits assessment of left ventricular function and regional wall motion. The measurement of ventricular volumes, ejection fraction and regional wall motion adds significantly to the determination of hemodynamic variables in assessing patients with acute infarction. The technique also permits detection of right ventricular dysfunction. Performance of a combination of these radioactive tracer techniques is often advantageous, particularly in patients with suspected infarction. The techniques can establish whether infarction is present, whether it is acute, where the damage is located and how extensive it is; they can also provide a measure of the effect of this damage on left ventricular function

  12. Compromised Global and Regional Cerebral Blood Flow in Congestive Heart Failure

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. S.; Kim, J. J.; Im, K. C.; Moon, D. H. [College of Medicine, Univ. of Ulsan, Seoul (Korea, Republic of)

    2003-07-01

    It has been known that cerebral perfusion is maintained in patients with congestive heart failure (CHF) by a complex series of compensatory mechanisms. However cognitive impairment is a common problem experienced by patients with CHF and may result from deranged cerebral perfusion. We prospectively investigated the global and regional CBF of patients with CHF and compared the results with that of normal controls. Thirty two patients (M/F: 22/10, 4211 yr) with CHF (LVEF=218.1%) and 10 healthy controls (M/F: 6/4, 398 yr) were prospectively studied. No patients had cerebrovascular disease or other disease affecting cognitive function. All patients and normal controls underwent radionuclide angiography including cerebral hemispheres and aortic arch, and brain perfusion SPECT using Tc-99m ECD. Global CBF was measured non-invasively by the application of Patlak plot graphical analysis. Quantitative rCBF images were obtained from SPECT image using global CBF values, regional/global count ratios, and Lassen's linearization correction algorithm. Difference of regional CBF between CHF and normal control were assessed using a SPM99 without global count normalization (uncorrected p<0.0001, extent threshold>100 voxels). Global CBF (41.54.7 ml/min/100g) of the patients with CHF were significantly lower than those (49.15.7 ml/min/100g) of controls (p<0.001). Regional CBF was significantly decreased in frontal, temporal and parietal neocortex of both cerebral hemispheres compared to normal controls. Regional rCBF of basal ganglia, thalamus, and brain stem were preserved, even though global CBF was variably compromised. Our study show that global CBF is significantly decreased in CHF and regional CBF of frontal, parietal and temporal neocortex is compromised preferentially. Further studies would be needed to investigate the relationship of rCBF change and cognitive impairment in patients with CHF.

  13. Turbine airfoil with outer wall thickness indicators

    Science.gov (United States)

    Marra, John J; James, Allister W; Merrill, Gary B

    2013-08-06

    A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

  14. Changing trend in congenital abdominal wall defects in Eastern region of Ireland.

    LENUS (Irish Health Repository)

    McDonnell, R

    2002-09-01

    In the past six years, there have been reports from abroad of an unexplained rise in the birth prevalence rate of the congenital abdominal wall defect gastroschisis, while rates for the macroscopically similar anomaly omphalocoele have remained stable. The Dublin EUROCAT Registry of congenital anomalies monitors trends in the birth prevalence of birth defects in the eastern region of Ireland. We analysed births of children with omphalocoele and gastroschisis born in the period 1981-2000, with comparisons of a number of demographic and obstetric variables. During the 20 year period the birth prevalence rate for omphalocoele remained stable at 2.5\\/10,000 births, whereas the rate for gastroschisis increased significantly during the 1990s from 1.0\\/10,000 in 1991 to 4.9\\/10,000 in 2000. Most of the increase occurred among mothers under 25 years of age. Omphalocoele was associated with a relatively high proportion of other major congenital anomalies. This study showed that there has been an unexpected rise in the birth prevalence of gastroschisis in the region, similar to that experienced in other countries in the same time period and likely to have common aetiological features.

  15. Importance of congestive heart failure and interaction of congestive heart failure and left ventricular systolic function on prognosis in patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Køber, L; Torp-Pedersen, C; Pedersen, O D

    1996-01-01

    or persistent. Wall motion index and CHF are correlated. Furthermore, there is an interaction between wall motion index and CHF. The prognostic importance of wall motion index depends on whether patients have CHF or not: the risk ratio associated with decreasing 1 wall motion index unit is 3.0 (2.6 to 3......Left ventricular (LV) systolic function and congestive heart failure (CHF) are important predictors of long-term mortality after acute myocardial infarction. The importance of transient CHF and the interaction of CHF and LV function on prognosis has not been studied in detail previously....... In the TRAndolapril Cardiac Evaluation Study, 6,676 consecutive patients with acute myocardial infarction 1 to 6 days earlier had LV systolic function quantified as wall motion index (echocardiography), which is closely correlated to LV ejection fraction. To study the interaction of CHF and wall motion index on long...

  16. Higher coronary heart disease and heart attack morbidity in Appalachian coal mining regions

    Energy Technology Data Exchange (ETDEWEB)

    Hendryx, M.; Zullig, K.J. [West Virginia University, Morgantown, WV (United States). Dept. of Community Medicine

    2009-11-15

    This study analyzes the U.S. 2006 Behavioral Risk Factor Surveillance System survey data (N = 235,783) to test whether self-reported cardiovascular disease rates are higher in Appalachian coal mining counties compared to other counties after control for other risks. Dependent variables include self-reported measures of ever (1) being diagnosed with cardiovascular disease (CVD) or with a specific form of CVD including (2) stroke, (3) heart attack, or (4) angina or coronary heart disease (CHD). Independent variables included coal mining, smoking, BMI, drinking, physician supply, diabetes co-morbidity, age, race/ethnicity, education, income, and others. SUDAAN Multilog models were estimated, and odds ratios tested for coal mining effects. After control for covariates, people in Appalachian coal mining areas reported significantly higher risk of CVD (OR = 1.22, 95% CI = 1.14-1.30), angina or CHO (OR = 1.29, 95% C1 = 1.19-1.39) and heart attack (OR = 1.19, 95% C1 = 1.10-1.30). Effects were present for both men and women. Cardiovascular diseases have been linked to both air and water contamination in ways consistent with toxicants found in coal and coal processing. Future research is indicated to assess air and water quality in coal mining communities in Appalachia, with corresponding environmental programs and standards established as indicated.

  17. Phenomenology of wall-bounded Newtonian turbulence.

    Science.gov (United States)

    L'vov, Victor S; Pomyalov, Anna; Procaccia, Itamar; Zilitinkevich, Sergej S

    2006-01-01

    We construct a simple analytic model for wall-bounded turbulence, containing only four adjustable parameters. Two of these parameters are responsible for the viscous dissipation of the components of the Reynolds stress tensor. The other two parameters control the nonlinear relaxation of these objects. The model offers an analytic description of the profiles of the mean velocity and the correlation functions of velocity fluctuations in the entire boundary region, from the viscous sublayer, through the buffer layer, and further into the log-law turbulent region. In particular, the model predicts a very simple distribution of the turbulent kinetic energy in the log-law region between the velocity components: the streamwise component contains a half of the total energy whereas the wall-normal and cross-stream components contain a quarter each. In addition, the model predicts a very simple relation between the von Kármán slope k and the turbulent velocity in the log-law region v+ (in wall units): v+=6k. These predictions are in excellent agreement with direct numerical simulation data and with recent laboratory experiments.

  18. The effect of partial poloidal wall sections on the wall stabilization of external kink modes

    International Nuclear Information System (INIS)

    Ward, D.J.

    1996-02-01

    An analysis of the effect on the wall stabilization of external kink modes due to toroidally continuous gaps in the resistive wall is performed. The effects with and without toroidal rotation are studied. For a high-β equilibrium, the mode structure is localized on the outboard side. Therefore, outboard gaps greatly increase the growth rate when there is no rotation. For resistive wall stabilization by toroidal rotation, the presence of gaps has the same effect as moving the wall farther away, i.e. destabilizing for the ideal plasma mode, and stabilizing for the resistive wall mode. The region of stability, in terms of wall position, is reduced in size and moved closer to the plasma. However, complete stabilization becomes possible at considerably reduced rotation frequencies. For a high-β, reverse-shear equilibrium both the resistive wall mode and the ideal plasma mode can be stabilized by close fitting discrete passive plates on the outboard side. The necessary toroidal rotation frequency to stabilize the resistive wall mode using these plates is reduced by a factor of three compared to that for a poloidally continuous and complete wall at the same plasma-wall separation. (author) 15 figs., 24 refs

  19. MHD stabilization of high β mirror plasma partially enclosed by conducting wall

    International Nuclear Information System (INIS)

    Li, X.Z.; Kesner, J.; Lane, B.

    1985-04-01

    An MHD formulation is used to study a wall stabilized high β mirror plasma with isotropic pressure. The stabilizing wall extends axially only a part of the distance between the mirror midplane and throat. We model this arrangement using a wall that approaches the plasma surface in the bad curvature region and is distant from the plasma in the good curvature region. A variational method is used to solve the equation in the distant wall region and an iterative method is used to solve the equation when the wall is close to the plasma. A jump condition is used to connect the regions of close and distant plasma-wall proximity. A simple trial function is used to perform the variational calculation (the choice of trial function is substantiated by an exact numerical solution). The results show that for a low mirror ratio case more conducting wall surface is needed for stability than in the high mirror ratio case. This agrees with the physical mechanism of the wall stabilization

  20. Postmortem magnetic resonance imaging: Reproducing typical autopsy heart measurements.

    Science.gov (United States)

    Ampanozi, Garyfalia; Hatch, Gary M; Flach, Patricia M; Thali, Michael J; Ruder, Thomas D

    2015-11-01

    The aim of this study was to evaluate the utility of cardiac postmortem magnetic resonance (PMMR) to perform routine measurements of the ventricular wall thicknesses and the heart valves and to assess if imaging measurements are consistent with traditional autopsy measurements. In this retrospective study, 25 cases with cardiac PMMR and subsequent autopsy were included. The thicknesses of the myocardial walls as well as the circumferences of all heart valves were measured on cardiac PMMR and compared to autopsy measurements. Paired samples T-test and the Wilcoxon-Signed rank test, were used to compare autopsy and cardiac PMMR measurements. For exploring correlations, the Pearson's Correlation coefficient and the Spearman's Rho test were used. Cardiac PMMR measurements of the aortic and pulmonary valve circumferences showed no significant differences from autopsy measurements. The mitral and tricuspid valves circumferences differed significantly from autopsy measurements. Left myocardial and right myocardial wall thickness also differed significantly from autopsy measurements. Left and right myocardial wall thickness, and tricuspid valve circumference measurements on cardiac PMMR and autopsy, correlated strongly and significantly. Several PMMR measurements of cardiac parameters differ significantly from corresponding autopsy measurements. However, there is a strong correlation between cardiac PMMR measurements and autopsy measurements in the majority of these parameters. It is important to note that myocardial walls are thicker when measured in situ on cardiac PMMR than when measured at autopsy. Investigators using post-mortem MR should be aware of these differences in order to avoid false diagnoses of cardiac pathology based on cardiac PMMR. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. The usefulness of treatment evaluation of severe heart failure by ECG-gated myocardial SPECT

    International Nuclear Information System (INIS)

    Ohkoshi, Nobuyuki; Watanabe, Shingo; Matsumoto, Tooru

    2011-01-01

    Our purpose of study was to investigate the usefulness of treatment evaluation of severe heart failure by Electrocardiogram (ECG)-gated myocardial single photon emission computed tomography (SPECT). We evaluated the cardiac function in the case of severe heart failure by gated SPECT and compared it with the cardiac function obtained by left ventriculography (LVG), echocardiography, cardiac MRI, and B-type natriuretic peptide (BNP) values. We investigated the correlation of ejection fraction (EF), time lag of wall motion between the septal and lateral walls of the left ventricle for cardiac resynchronization therapy (CRT) and wall thickening (WT). We classified the left ventricular (LV) into basal, middle and apical areas for comparison of WT. We investigated the effect of a perfusion defect score in these comparisons. The gated SPECT results were correlated with comparative subjects in EF. The results were correlated with MRI on the middle area of the LV in the comparison of WT. We thought it was possible that there was an effect from a perfusion defect score in a time lag comparison of wall motion. Treatment evaluation of severe heart failure by gated SPECT is useful, because it is able to obtain three-dimensional cardiac function analysis, and it offers objectivity and reproducible quantitative evaluation. At the same time, perfusion SPECT is helpful for CRT and LV-plasty. (author)

  2. Sound Transmission in a Duct with Sudden Area Expansion, Extended Inlet, and Lined Walls in Overlapping Region

    Directory of Open Access Journals (Sweden)

    Ahmet Demir

    2016-01-01

    Full Text Available The transmission of sound in a duct with sudden area expansion and extended inlet is investigated in the case where the walls of the duct lie in the finite overlapping region lined with acoustically absorbent materials. By using the series expansion in the overlap region and using the Fourier transform technique elsewhere we obtain a Wiener-Hopf equation whose solution involves a set of infinitely many unknown expansion coefficients satisfying a system of linear algebraic equations. Numerical solution of this system is obtained for various values of the problem parameters, whereby the effects of these parameters on the sound transmission are studied.

  3. Athlete's Heart: Is the Morganroth Hypothesis Obsolete?

    Science.gov (United States)

    Haykowsky, Mark J; Samuel, T Jake; Nelson, Michael D; La Gerche, Andre

    2018-05-01

    In 1975, Morganroth and colleagues reported that the increased left ventricular (LV) mass in highly trained endurance athletes versus nonathletes was primarily due to increased end-diastolic volume while the increased LV mass in resistance trained athletes was solely due to an increased LV wall thickness. Based on the divergent remodelling patterns observed, Morganroth and colleagues hypothesised that the increased "volume" load during endurance exercise may be similar to that which occurs in patients with mitral or aortic regurgitation while the "pressure" load associated with performing a Valsalva manoeuvre (VM) during resistance exercise may mimic the stress imposed on the heart by systemic hypertension or aortic stenosis. Despite widespread acceptance of the four-decade old Morganroth hypothesis in sports cardiology, some investigators have questioned whether such a divergent "athlete's heart" phenotype exists. Given this uncertainty, the purpose of this brief review is to re-evaluate the Morganroth hypothesis regarding: i) the acute effects of resistance exercise performed with a brief VM on LV wall stress, and the patterns of LV remodelling in resistance-trained athletes; ii) the acute effects of endurance exercise on biventricular wall stress, and the time course and pattern of LV and right ventricular (RV) remodelling with endurance training; and iii) the value of comparing "loading" conditions between athletes and patients with cardiac pathology. Copyright © 2018. Published by Elsevier B.V.

  4. Comparison among patients with hypertrophic cardiomyopathy, hypertrophic cardiomyopathy with hypertension and hypertensive heart disease by 123I-BMIPP myocardial scintigraphy

    International Nuclear Information System (INIS)

    Yoneyama, Satoshi; Sugihara, Hiroki; Ito, Kazuki

    1997-01-01

    The usefulness of 123 I-BMIPP myocardial SPECT in discriminating hypertrophic cardiomyopathy (46 patients), hypertrophic cardiomyopathy with hypertension (23 patients), and hypertensive hypertrophic heart (20 patients) was studied. SPECT image was divided into 17 domains, and dimension of decreased accumulation was decided visually at each domain as four classes called defect score (DS). Summation of DS (TDS) of each group was used to compare frequency and dimension of decreased accumulation, and characteristic of each site. Frequency of decreased accumulation and TDS in hypertrophic cardiomyopathy were similar in dimension with those in hypertrophic cardiomyopathy with hypertension, and those data in hypertensive hypertrophic heart were lower than those in above-mentioned 2 groups. In the cases of hypertrophic cardiomyopathy and hypertrophic cardiomyopathy with hypertension, decreased accumulation site was similar and was anterior wall-septum junction, septum-posterior wall junction and apex of heart. In the case of hypertensive hypertrophic heart, decreased accumulation site was only the posterior wall. Frequency, dimension and site of decreased accumulation in hypertrophic cardiomyopathy were different from those in hypertensive hypertrophic heart, and BMIPP was thought to be useful in discriminating these diseases. (K.H.)

  5. Elevated uptake of plasma macromolecules by regions of arterial wall predisposed to plaque instability in a mouse model.

    Directory of Open Access Journals (Sweden)

    Zahra Mohri

    Full Text Available Atherosclerosis may be triggered by an elevated net transport of lipid-carrying macromolecules from plasma into the arterial wall. We hypothesised that whether lesions are of the thin-cap fibroatheroma (TCFA type or are less fatty and more fibrous depends on the degree of elevation of transport, with greater uptake leading to the former. We further hypothesised that the degree of elevation can depend on haemodynamic wall shear stress characteristics and nitric oxide synthesis. Placing a tapered cuff around the carotid artery of apolipoprotein E -/- mice modifies patterns of shear stress and eNOS expression, and triggers lesion development at the upstream and downstream cuff margins; upstream but not downstream lesions resemble the TCFA. We measured wall uptake of a macromolecular tracer in the carotid artery of C57bl/6 mice after cuff placement. Uptake was elevated in the regions that develop lesions in hyperlipidaemic mice and was significantly more elevated where plaques of the TCFA type develop. Computational simulations and effects of reversing the cuff orientation indicated a role for solid as well as fluid mechanical stresses. Inhibiting NO synthesis abolished the difference in uptake between the upstream and downstream sites. The data support the hypothesis that excessively elevated wall uptake of plasma macromolecules initiates the development of the TCFA, suggest that such uptake can result from solid and fluid mechanical stresses, and are consistent with a role for NO synthesis. Modification of wall transport properties might form the basis of novel methods for reducing plaque rupture.

  6. Congenital Heart Disease: Causes, Diagnosis, Symptoms, and Treatments.

    Science.gov (United States)

    Sun, RongRong; Liu, Min; Lu, Lei; Zheng, Yi; Zhang, Peiying

    2015-07-01

    The congenital heart disease includes abnormalities in heart structure that occur before birth. Such defects occur in the fetus while it is developing in the uterus during pregnancy. About 500,000 adults have congenital heart disease in USA (WebMD, Congenital heart defects medications, www.WebMD.com/heart-disease/tc/congenital-heart-defects-medications , 2014). 1 in every 100 children has defects in their heart due to genetic or chromosomal abnormalities, such as Down syndrome. The excessive alcohol consumption during pregnancy and use of medications, maternal viral infection, such as Rubella virus, measles (German), in the first trimester of pregnancy, all these are risk factors for congenital heart disease in children, and the risk increases if parent or sibling has a congenital heart defect. These are heart valves defects, atrial and ventricular septa defects, stenosis, the heart muscle abnormalities, and a hole inside wall of the heart which causes defect in blood circulation, heart failure, and eventual death. There are no particular symptoms of congenital heart disease, but shortness of breath and limited ability to do exercise, fatigue, abnormal sound of heart as heart murmur, which is diagnosed by a physician while listening to the heart beats. The echocardiogram or transesophageal echocardiogram, electrocardiogram, chest X-ray, cardiac catheterization, and MRI methods are used to detect congenital heart disease. Several medications are given depending on the severity of this disease, and catheter method and surgery are required for serious cases to repair heart valves or heart transplantation as in endocarditis. For genetic study, first DNA is extracted from blood followed by DNA sequence analysis and any defect in nucleotide sequence of DNA is determined. For congenital heart disease, genes in chromosome 1 show some defects in nucleotide sequence. In this review the causes, diagnosis, symptoms, and treatments of congenital heart disease are described.

  7. Radiochemicals used to scan the heart

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Techniques for heart scanning using 201 Tl and /sup 99m/Tc pyrophosphate are discussed. Thallium-201, produced artificially in a cyclotron, concentrates in normal heart muscle but not in abnormal tissue. Technetium-99m is deposited in mitochondria of heart cells that are irreversibly damaged. The combined use of 201 Tl and /sup 99m/Tc makes it possible to identify regions of recent heart damage as well as older heart damage. Advantages of using 129 Cs for heart scanning are also discussed

  8. Cardiorespiratory effects of inelastic chest wall restriction.

    Science.gov (United States)

    Miller, Jordan D; Beck, Kenneth C; Joyner, Michael J; Brice, A Glenn; Johnson, Bruce D

    2002-06-01

    We examined the effects of chest wall restriction (CWR) on cardiorespiratory function at rest and during exercise in healthy subjects in an attempt to approximate the cardiorespiratory interactions observed in clinical conditions that result in restrictive lung and/or chest wall changes and a reduced intrathoracic space. Canvas straps were applied around the thorax and abdomen so that vital capacity was reduced by >35%. Data were acquired at rest and during cycle ergometry at 25 and 45% of peak workloads. CWR elicited significant increases in the flow-resistive work performed on the lung (160%) and the gastric pressure-time integral (>400%) at the higher workload, but it resulted in a decrease in the elastic work performed on the lung (56%) compared with control conditions. With CWR, heart rate increased and stroke volume (SV) fell, resulting in >10% fall in cardiac output at rest and during exercise at matched workloads (P < 0.05). Blood pressure and catecholamines were significantly elevated during CWR exercise conditions (P < 0.05). We conclude that CWR significantly impairs SV during exercise and that a compensatory increase in heart rate does not prevent a significant reduction in cardiac output. O(2) consumption appears to be maintained via increased extraction and a redistribution of blood flow via sympathetic activation.

  9. Intermittency and scaling laws for wall bounded turbulence

    NARCIS (Netherlands)

    Benzi, R.; Amati, G.; Casciola, C.M.; Toschi, F.; Piva, R.

    1999-01-01

    Well defined scaling laws clearly appear in wall bounded turbulence, very close to the wall, where a distinct violation of the refined Kolmogorov similarity hypothesis (RKSH) occurs together with the simultaneous persistence of scaling laws. A new form of RKSH for the wall region is here proposed in

  10. Intermittency and scaling laws for wall bounded turbulence

    OpenAIRE

    Benzi, R.; Amati, G.; Casciola, C. M.; Toschi, F.; Piva, R.

    1998-01-01

    Well defined scaling laws clearly appear in wall bounded turbulence, even very close to the wall, where a distinct violation of the refined Kolmogorov similarity hypothesis (RKSH) occurs together with the simultaneous persistence of scaling laws. A new form of RKSH for the wall region is here proposed in terms of the structure functions of order two which, in physical terms, confirms the prevailing role of the momentum transfer towards the wall in the near wall dynamics.

  11. Nonsingular walls in plane cholesteric layers

    International Nuclear Information System (INIS)

    Belyakov, V A; Osipov, M A; Stewart, I W

    2006-01-01

    The structure of a straight interface (wall) between regions with differing values of the pitch in planar cholesteric layers with finite strength of the surface anchoring is investigated theoretically. It is found that the shape and strength of the anchoring potential influences essentially the structure of the wall and a motionless wall between thermodynamically stable regions without a singularity in the director distribution in the layer can exist for sufficiently weak anchoring only. More specifically, for the existence of such a wall the dimensionless parameter S d = K 22 /Wd (where W is the depth of the anchoring potential, K 22 is the elastic twist modulus and d is the layer thickness) should exceed its critical value, which is dependent on the shape of the anchoring potential. General equations describing the director distribution in the wall are presented. Detailed analysis of these equations is carried out for the case of infinitely strong anchoring at one surface and finite anchoring strength at the second layer surface. It is shown that the wall width L is directly dependent upon the shape and strength of the anchoring potential and that its estimate ranges from d to (dL p ) 1/2 (where L p = K 22 /W is the penetration length), corresponding to different anchoring strengths and shape potentials. The dependence of the director distribution in the wall upon all three Frank elastic moduli is analytically found for some specific limiting cases of the model anchoring potentials. Motion of the wall is briefly investigated and the corresponding calculations performed under the assumption that the shape of a moving wall is the same as a motionless one. It is noted that experimental investigation of the walls in planar cholesteric layers can be used for the determination of the actual shape of surface anchoring potentials

  12. Mathematical Modeling of Flow Characteristics in the Embryonic Chick Heart

    DEFF Research Database (Denmark)

    Heebøll-Christensen, Jesper

    This ph.d. thesis contains the mathematical modeling of fluid dynamical phenomena in the tubular embryonic chick heart at HH-stages 10, 12, 14, and 16. The models are constructed by application of energy bond technique and involve the elasticity of heart walls with elliptic cross-section, Womersley...... modified inertia, and resistance due to friction and curvature of the multilayered tubular heart. Through the modeling, flow conditions in the embryonic heart are characterized. The models suggest that eccentric rather than concentric deformation of the beating heart is optimal for mean flows induced...... the models are not conclusive on this point. In addition the Liebau effect is investigated in a simpler system containing two elastic tubes joined to form a liquid filled ring, with a compression pump at an asymmetric location. Through comparison to other reports the system validates model construction...

  13. Cardiac injury of the newborn mammalian heart accelerates cardiomyocyte terminal differentiation

    DEFF Research Database (Denmark)

    Zebrowski, David C.; Jensen, Charlotte H.; Becker, Robert

    2017-01-01

    exhibited midbody formation consistent with successful abscission, whereas those from 3 day-old cardiomyocytes after apical resection exhibited midbody formation consistent with abscission failure. Lastly, injured hearts failed to fully regenerate as evidenced by persistent scarring and reduced wall motion......After birth cardiomyocytes undergo terminal differentiation, characterized by binucleation and centrosome disassembly, rendering the heart unable to regenerate. Yet, it has been suggested that newborn mammals regenerate their hearts after apical resection by cardiomyocyte proliferation. Thus, we...... increased rate of binucleation there was a nearly 2-fold increase in the number of cardiomyocytes in mitosis indicating that the majority of injury-induced cardiomyocyte cell cycle activity results in binucleation, not proliferation. Concurrently, cardiomyocytes undergoing cytokinesis from embryonic hearts...

  14. Sunspot Light Walls Suppressed by Nearby Brightenings

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shuhong; Zhang, Jun; Hou, Yijun; Li, Xiaohong [CAS Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Erdélyi, Robertus [Solar Physics and Space Plasma Research Centre, School of Mathematics and Statistics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Yan, Limei, E-mail: shuhongyang@nao.cas.cn [Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

    2017-07-01

    Light walls, as ensembles of oscillating bright structures rooted in sunspot light bridges, have not been well studied, although they are important for understanding sunspot properties. Using the Interface Region Imaging Spectrograph and Solar Dynamics Observatory observations, here we study the evolution of two oscillating light walls each within its own active region (AR). The emission of each light wall decays greatly after the appearance of adjacent brightenings. For the first light wall, rooted within AR 12565, the average height, amplitude, and oscillation period significantly decrease from 3.5 Mm, 1.7 Mm, and 8.5 minutes to 1.6 Mm, 0.4 Mm, and 3.0 minutes, respectively. For the second light wall, rooted within AR 12597, the mean height, amplitude, and oscillation period of the light wall decrease from 2.1 Mm, 0.5 Mm, and 3.0 minutes to 1.5 Mm, 0.2 Mm, and 2.1 minutes, respectively. Particularly, a part of the second light wall even becomes invisible after the influence of a nearby brightening. These results reveal that the light walls are suppressed by nearby brightenings. Considering the complex magnetic topology in light bridges, we conjecture that the fading of light walls may be caused by a drop in the magnetic pressure, where the flux is canceled by magnetic reconnection at the site of the nearby brightening. Another hypothesis is that the wall fading is due to the suppression of driver source ( p -mode oscillation), resulting from the nearby avalanche of downward particles along reconnected brightening loops.

  15. Comparative study of diastolic filling under varying left ventricular wall stiffness

    Science.gov (United States)

    Mekala, Pritam; Santhanakrishnan, Arvind

    2014-11-01

    Pathological remodeling of the human cardiac left ventricle (LV) is observed in hypertensive heart failure as a result of pressure overload. Myocardial stiffening occurs in these patients prior to chronic maladaptive changes, resulting in increased LV wall stiffness. The goal of this study was to investigate the change in intraventricular filling fluid dynamics inside a physical model of the LV as a function of wall stiffness. Three LV models of varying wall stiffness were incorporated into an in vitro flow circuit driven by a programmable piston pump. Windkessel elements were used to tune the inflow and systemic pressure in the model with least stiffness to match healthy conditions. Models with stiffer walls were comparatively tested maintaining circuit compliance, resistance and pump amplitude constant. 2D phase-locked PIV measurements along the central plane showed that with increase in wall stiffness, the peak velocity and cardiac output inside the LV decreased. Further, inflow vortex ring propagation toward the LV apex was reduced with increasing stiffness. The above findings indicate the importance of considering LV wall relaxation characteristics in pathological studies of filling fluid dynamics.

  16. Geographic differences in heart failure trials.

    Science.gov (United States)

    Ferreira, João Pedro; Girerd, Nicolas; Rossignol, Patrick; Zannad, Faiez

    2015-09-01

    Randomized controlled trials (RCTs) are essential to develop advances in heart failure (HF). The need for increasing numbers of patients (without substantial cost increase) and generalization of results led to the disappearance of international boundaries in large RCTs. The significant geographic differences in patients' characteristics, outcomes, and, most importantly, treatment effect observed in HF trials have recently been highlighted. Whether the observed regional discrepancies in HF trials are due to trial-specific issues, patient heterogeneity, structural differences in countries, or a complex interaction between factors are the questions we propose to debate in this review. To do so, we will analyse and review data from HF trials conducted in different world regions, from heart failure with preserved ejection fraction (HF-PEF), heart failure with reduced ejection fraction (HF-REF), and acute heart failure (AHF). Finally, we will suggest objective and actionable measures in order to mitigate regional discrepancies in future trials, particularly in HF-PEF where prognostic modifying treatments are urgently needed and in which trials are more prone to selection bias, due to a larger patient heterogeneity. © 2015 The Authors European Journal of Heart Failure © 2015 European Society of Cardiology.

  17. The plasma-wall transition layers in the presence of collisions with a magnetic field parallel to the wall

    Science.gov (United States)

    Moritz, J.; Faudot, E.; Devaux, S.; Heuraux, S.

    2018-01-01

    The plasma-wall transition is studied by means of a particle-in-cell (PIC) simulation in the configuration of a parallel to the wall magnetic field (B), with collisions between charged particles vs. neutral atoms taken into account. The investigated system consists of a plasma bounded by two absorbing walls separated by 200 electron Debye lengths (λd). The strength of the magnetic field is chosen such as the ratio λ d / r l , with rl being the electron Larmor radius, is smaller or larger than unity. Collisions are modelled with a simple operator that reorients randomly ion or electron velocity, keeping constant the total kinetic energy of both the neutral atom (target) and the incident charged particle. The PIC simulations show that the plasma-wall transition consists in a quasi-neutral region (pre-sheath), from the center of the plasma towards the walls, where the electric potential or electric field profiles are well described by an ambipolar diffusion model, and in a second region at the vicinity of the walls, called the sheath, where the quasi-neutrality breaks down. In this peculiar geometry of B and for a certain range of the mean-free-path, the sheath is found to be composed of two charged layers: the positive one, close to the walls, and the negative one, towards the plasma and before the neutral pre-sheath. Depending on the amplitude of B, the spatial variation of the electric potential can be non-monotonic and presents a maximum within the sheath region. More generally, the sheath extent as well as the potential drop within the sheath and the pre-sheath is studied with respect to B, the mean-free-path, and the ion and electron temperatures.

  18. Intrinsic and extrinsic innervation of the heart in zebrafish (Danio rerio).

    Science.gov (United States)

    Stoyek, Matthew R; Croll, Roger P; Smith, Frank M

    2015-08-01

    In the vertebrate heart the intracardiac nervous system is the final common pathway for autonomic control of cardiac output, but the neuroanatomy of this system is not well understood. In this study we investigated the innervation of the heart in a model vertebrate, the zebrafish. We used antibodies against acetylated tubulin, human neuronal protein C/D, choline acetyltransferase, tyrosine hydroxylase, neuronal nitric oxide synthase, and vasoactive intestinal polypeptide to visualize neural elements and their neurotransmitter content. Most neurons were located at the venous pole in a plexus around the sinoatrial valve; mean total number of cells was 197 ± 23, and 92% were choline acetyltransferase positive, implying a cholinergic role. The plexus contained cholinergic, adrenergic, and nitrergic axons and vasoactive intestinal polypeptide-positive terminals, some innervating somata. Putative pacemaker cells near the plexus showed immunoreactivity for hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) and the transcription factor Islet-1 (Isl1). The neurotracer neurobiotin showed that extrinsic axons from the left and right vagosympathetic trunks innervated the sinoatrial plexus proximal to their entry into the heart; some extrinsic axons from each trunk also projected into the medial dorsal plexus region. Extrinsic axons also innervated the atrial and ventricular walls. An extracardiac nerve trunk innervated the bulbus arteriosus and entered the arterial pole of the heart to innervate the proximal ventricle. We have shown that the intracardiac nervous system in the zebrafish is anatomically and neurochemically complex, providing a substrate for autonomic control of cardiac effectors in all chambers. © 2015 Wiley Periodicals, Inc.

  19. Granular packings with moving side walls

    International Nuclear Information System (INIS)

    Landry, James W.; Grest, Gary Stephen

    2004-01-01

    The effects of movement of the side walls of a confined granular packing are studied by discrete element, molecular dynamics simulations. The dynamical evolution of the stress is studied as a function of wall movement both in the direction of gravity as well as opposite to it. For all wall velocities explored, the stress in the final state of the system after wall movement is fundamentally different from the original state obtained by pouring particles into the container and letting them settle under the influence of gravity. The original packing possesses a hydrostaticlike region at the top of the container which crosses over to a depth-independent stress. As the walls are moved in the direction opposite to gravity, the saturation stress first reaches a minimum value independent of the wall velocity, then increases to a steady-state value dependent on the wall velocity. After wall movement ceases and the packing reaches equilibrium, the stress profile fits the classic Janssen form for high wall velocities, while some deviations remain for low wall velocities. The wall movement greatly increases the number of particle-wall and particle-particle forces at the Coulomb criterion. Varying the wall velocity has only small effects on the particle structure of the final packing so long as the walls travel a similar distance.

  20. Complex regional pain syndrome with associated chest wall dystonia: a case report

    Directory of Open Access Journals (Sweden)

    Schwartzman Robert J

    2011-09-01

    Full Text Available Abstract Patients with complex regional pain syndrome (CRPS often suffer from an array of associated movement disorders, including dystonia of an affected limb. We present a case of a patient with long standing CRPS after a brachial plexus injury, who after displaying several features of the movement disorder previously, developed painful dystonia of chest wall musculature. Detailed neurologic examination found palpable sustained contractions of the pectoral and intercostal muscles in addition to surface allodynia. Needle electromyography of the intercostal and paraspinal muscles supported the diagnosis of dystonia. In addition, pulmonary function testing showed both restrictive and obstructive features in the absence of a clear cardiopulmonary etiology. Treatment was initiated with intrathecal baclofen and the patient had symptomatic relief and improvement of dystonia. This case illustrates a novel form of the movement disorder associated with CRPS with response to intrathecal baclofen treatment.

  1. Automated segmentation of the atrial region and fossa ovalis towards computer-aided planning of inter-atrial wall interventions.

    Science.gov (United States)

    Morais, Pedro; Vilaça, João L; Queirós, Sandro; Marchi, Alberto; Bourier, Felix; Deisenhofer, Isabel; D'hooge, Jan; Tavares, João Manuel R S

    2018-07-01

    Image-fusion strategies have been applied to improve inter-atrial septal (IAS) wall minimally-invasive interventions. Hereto, several landmarks are initially identified on richly-detailed datasets throughout the planning stage and then combined with intra-operative images, enhancing the relevant structures and easing the procedure. Nevertheless, such planning is still performed manually, which is time-consuming and not necessarily reproducible, hampering its regular application. In this article, we present a novel automatic strategy to segment the atrial region (left/right atrium and aortic tract) and the fossa ovalis (FO). The method starts by initializing multiple 3D contours based on an atlas-based approach with global transforms only and refining them to the desired anatomy using a competitive segmentation strategy. The obtained contours are then applied to estimate the FO by evaluating both IAS wall thickness and the expected FO spatial location. The proposed method was evaluated in 41 computed tomography datasets, by comparing the atrial region segmentation and FO estimation results against manually delineated contours. The automatic segmentation method presented a performance similar to the state-of-the-art techniques and a high feasibility, failing only in the segmentation of one aortic tract and of one right atrium. The FO estimation method presented an acceptable result in all the patients with a performance comparable to the inter-observer variability. Moreover, it was faster and fully user-interaction free. Hence, the proposed method proved to be feasible to automatically segment the anatomical models for the planning of IAS wall interventions, making it exceptionally attractive for use in the clinical practice. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Development of cardiac parasympathetic neurons, glial cells, and regional cholinergic innervation of the mouse heart.

    Science.gov (United States)

    Fregoso, S P; Hoover, D B

    2012-09-27

    Very little is known about the development of cardiac parasympathetic ganglia and cholinergic innervation of the mouse heart. Accordingly, we evaluated the growth of cholinergic neurons and nerve fibers in mouse hearts from embryonic day 18.5 (E18.5) through postnatal day 21(P21). Cholinergic perikarya and varicose nerve fibers were identified in paraffin sections immunostained for the vesicular acetylcholine transporter (VAChT). Satellite cells and Schwann cells in adjacent sections were identified by immunostaining for S100β calcium binding protein (S100) and brain-fatty acid binding protein (B-FABP). We found that cardiac ganglia had formed in close association to the atria and cholinergic innervation of the atrioventricular junction had already begun by E18.5. However, most cholinergic innervation of the heart, including the sinoatrial node, developed postnatally (P0.5-P21) along with a doubling of the cross-sectional area of cholinergic perikarya. Satellite cells were present throughout neonatal cardiac ganglia and expressed primarily B-FABP. As they became more mature at P21, satellite cells stained strongly for both B-FABP and S100. Satellite cells appeared to surround most cardiac parasympathetic neurons, even in neonatal hearts. Mature Schwann cells, identified by morphology and strong staining for S100, were already present at E18.5 in atrial regions that receive cholinergic innervation at later developmental times. The abundance and distribution of S100-positive Schwann cells increased postnatally along with nerve density. While S100 staining of cardiac Schwann cells was maintained in P21 and older mice, Schwann cells did not show B-FABP staining at these times. Parallel development of satellite cells and cholinergic perikarya in the cardiac ganglia and the increase in abundance of Schwann cells and varicose cholinergic nerve fibers in the atria suggest that neuronal-glial interactions could be important for development of the parasympathetic nervous

  3. Heart position variability during voluntary moderate deep inspiration breath-hold radiotherapy for breast cancer determined by repeat CBCT scans.

    Science.gov (United States)

    van Haaren, Paul; Claassen-Janssen, Fiere; van de Sande, Ingrid; Boersma, Liesbeth; van der Sangen, Maurice; Hurkmans, Coen

    2017-08-01

    Voluntary moderate deep inspiration breath hold (vmDIBH) in left-sided breast cancer radiotherapy reduces cardiac dose. The aim of this study was to investigate heart position variability in vmDIBH using CBCT and to compare this variability with differences in heart position between vmDIBH and free breathing (FB). For 50 patients initial heart position with respect to the field edge (HP-FE) was measured on a vmDIBH planning CT scan. Breath-hold was monitored using an in-house developed vertical plastic stick. On pre-treatment CBCT scans, heart position variability with respect to the field edge (Δ HP-FE ) was measured, reflecting heart position variability when using an offline correction protocol. After registering the CBCT scan to the planning CT, heart position variability with respect to the chest wall (Δ HP-CW ) was measured, reflecting heart position variability when using an online correction protocol. As a control group, vmDIBH and FB computed tomography (CT) scans were acquired for 30 patients and registering both scans on the chest wall. For 34 out of 50 patients, the average HP-FE and HP-CW increased over the treatment course in comparison to the planning CT. Averaged over all patients and all treatment fractions, the Δ HP-FE and the Δ HP-CW was 0.8±4.2mm (range -9.4-+10.6mm) and 1.0±4.4mm (range -8.3-+10.4mm) respectively. The average gain in heart to chest wall distance was 11.8±4.6mm when using vmDIBH instead of FB. In conclusion, substantial variability in heart position using vmDIBH was observed during the treatment course. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  4. Ischaemic heart disease deaths in Brazil: current trends, regional disparities and future projections.

    Science.gov (United States)

    Baena, Cristina P; Chowdhury, Rajiv; Schio, Nicolle Amboni; Sabbag, Ary Elias; Guarita-Souza, Luiz Cesar; Olandoski, Marcia; Franco, Oscar H; Faria-Neto, José Rocha

    2013-09-01

    To quantify the trend of ischaemic heart disease (IHD) deaths in Brazil during the last decade (2000-2010) for various population characteristics and to forecast the upcoming mortality trends across regions in Brazil until the year 2015. Nationwide comparative observational study. The population studied encompassed all adult residents (≥ 20 years) living in five Brazilian regions between 2000 and 2010. Demographic, economic and mortality data were obtained from Brazilian National Mortality Data System and National Applied Economics Research Institute. Subnotified deaths were redistributed proportionally to IHD deaths. Age-standardised mortality rates (ASMRs) per 100 000 inhabitants, by sex and region, were calculated employing a standard Brazilian population and constructing multivariate regression models to quantify and to project temporal trends. Absolute numbers of death due to IHD and region-specific death rates in Brazil by age and sex. During the study period, 627 786 men and 452 690 women died due to IHD in Brazil. ASMR trends across all regions for men and women converged, driven by a declining trend in the South and Southeast and an opposite incline in the North and Northeast (p < 0.05). Future projections demonstrated potential widening of the observed North-South gap in coming years. The IHD death trend in Brazil has changed from a decline to a stagnant state. However, a significant discrepancy in mortality trends exists between the northern and southern regions, which is likely to widen further. Reappraisal of the public health policies tailored to populations with diverse socioeconomic structures is urgently required.

  5. Domain wall engineering through exchange bias

    International Nuclear Information System (INIS)

    Albisetti, E.; Petti, D.

    2016-01-01

    The control of the structure and position of magnetic domain walls is at the basis of the development of different magnetic devices and architectures. Several nanofabrication techniques have been proposed to geometrically confine and shape domain wall structures; however, a fine tuning of the position and micromagnetic configuration is hardly achieved, especially in continuous films. This work shows that, by controlling the unidirectional anisotropy of a continuous ferromagnetic film through exchange bias, domain walls whose spin arrangement is generally not favored by dipolar and exchange interactions can be created. Micromagnetic simulations reveal that the domain wall width, position and profile can be tuned by establishing an abrupt change in the direction and magnitude of the exchange bias field set in the system. - Highlights: • Micromagnetic simulations study domain walls in exchange biased thin films. • Novel domain wall configurations can be stabilized via exchange bias. • Domain walls nucleate at the boundary of regions with different exchange bias. • Domain wall width and spin profile are controlled by tuning the exchange bias.

  6. Influence of strong perturbations on wall-bounded flows

    Science.gov (United States)

    Buxton, O. R. H.; Ewenz Rocher, M.; Rodríguez-López, E.

    2018-01-01

    Single-point hot-wire measurements are made downstream of a series of spanwise repeating obstacles that are used to generate an artificially thick turbulent boundary layer. The measurements are made in the near field, in which the turbulent boundary layer is beginning to develop from the wall-bounded wakes of the obstacles. The recent paper of Rodríguez-López et al. [E. Rodríguez-López et al., Phys. Rev. Fluids 1, 074401 (2016), 10.1103/PhysRevFluids.1.074401] broadly categorized the mechanisms by which canonical turbulent boundary layers eventually develop from wall-bounded wakes into two distinct mechanisms, the wall-driven and wake-driven mechanisms. In the present work we attempt to identify the geometric parameters of tripping arrays that trigger these two mechanisms by examining the spectra of the streamwise velocity fluctuations and the intermittent outer region of the flow. Using a definition reliant upon the magnitude of the velocity fluctuations, an intermittency function is devised that can discriminate between turbulent and nonturbulent flow. These results are presented along with the spectra in order to try to ascertain which aspects of a trip's geometry are more likely to favor the wall-driven or wake-driven mechanism. The geometrical aspects of the trips tested are the aspect ratio, the total blockage, and the blockage at the wall. The results indicate that the presence, or not, of perforations is the most significant factor in affecting the flow downstream. The bleed of fluid through the perforations reenergizes the mean recirculation and leads to a narrower intermittent region with a more regular turbulent-nonturbulent interface. The near-wall turbulent motions are found to recover quickly downstream of all of the trips with a wall blockage of 50%, but a clear influence of the outer fluctuations, generated by the tip vortices of the trips, is observed in the near-wall region for the high total blockage trips. The trip with 100% wall blockage is

  7. Clinical evaluation of 123I-metaiodobenzylguanidine myocardial scintigram in patients with vascular heart disease

    International Nuclear Information System (INIS)

    Terada, Kouji; Sugihara, Hiroki; Shiga, Koji

    1995-01-01

    Myocardial sympathetic nerve function can be evaluated by 123 I-metaiodobenzylguanidine (MIBG) scintigraphy. Congestive heart failure is closely related to myocardial sympathetic nerve function. This study evaluated the severity of congestive heart failure in 30 patients with valvular heart disease [aortic regurgitation (AR): n=20, mean age=70±13 years; mitral regurgitation (MR): n=10, mean age=61±18 years], who had chronic heart failure by MIBG myocardial scintigraphy. Single photon emission computed tomography (SPECT) and anterior planar myocardial images were obtained 15 minutes (initial images) and 4 hours (delayed images) after injection of MIBG (111 MBq). Defect score was determined by the delayed SPECT images visually as a semi-quantitative index. Myocardial MIBG uptake was quantified by the heart to upper mediastinum uptake ratio on the delayed anterior planar images (H/M) and mean cardiac MIBG washout rate during 4 hours was calculated from the bull's eye display data (clearance). These indices were compared with the NYHA class and echocardiographic findings of the patients. MIBG regional defect in the delayed image was most frequently seen in the inferoposterior wall, and defect score and clearance were significantly higher and the H/M ratio was significantly lower in NYHA class III patients than in class II patients. In patients with AR, clearance significantly correlated with left ventricular end-systolic dimension. In patients with MR, both the H/M ratio and clearance significantly correlated with left atrial dimension. Defect score, H/M, and clearance were closely related to the severity of AR and MR. These results indicate that MIBG scan can be used to assess the severity of valvular heart disease. (author)

  8. Topological domain walls in helimagnets

    Science.gov (United States)

    Schoenherr, P.; Müller, J.; Köhler, L.; Rosch, A.; Kanazawa, N.; Tokura, Y.; Garst, M.; Meier, D.

    2018-05-01

    Domain walls naturally arise whenever a symmetry is spontaneously broken. They interconnect regions with different realizations of the broken symmetry, promoting structure formation from cosmological length scales to the atomic level1,2. In ferroelectric and ferromagnetic materials, domain walls with unique functionalities emerge, holding great promise for nanoelectronics and spintronics applications3-5. These walls are usually of Ising, Bloch or Néel type and separate homogeneously ordered domains. Here we demonstrate that a wide variety of new domain walls occurs in the presence of spatially modulated domain states. Using magnetic force microscopy and micromagnetic simulations, we show three fundamental classes of domain walls to arise in the near-room-temperature helimagnet iron germanium. In contrast to conventional ferroics, the domain walls exhibit a well-defined inner structure, which—analogous to cholesteric liquid crystals—consists of topological disclination and dislocation defects. Similar to the magnetic skyrmions that form in the same material6,7, the domain walls can carry a finite topological charge, permitting an efficient coupling to spin currents and contributions to a topological Hall effect. Our study establishes a new family of magnetic nano-objects with non-trivial topology, opening the door to innovative device concepts based on helimagnetic domain walls.

  9. Rationale, design and baseline results of the Treatment Optimisation in Primary care of Heart failure in the Utrecht region (TOPHU) study : a cluster randomised controlled trial

    NARCIS (Netherlands)

    Valk, Mark J.; Hoes, Arno W.; Mosterd, Arend; Landman, Marcel A.; Broekhuizen, Berna D L; Rutten, Frans H.

    2015-01-01

    BACKGROUND: Heart failure (HF) is mainly detected and managed in primary care, but the care is considered suboptimal. We present the rationale, design and baseline results of the Treatment Optimisation in Primary care of Heart failure in the Utrecht region (TOPHU) study. In this study we assess the

  10. The influence of wall orientation and exterior surface solar absorptivity on time lag and decrement factor in the Greek region

    Energy Technology Data Exchange (ETDEWEB)

    Kontoleon, K.J.; Eumorfopoulou, E.A. [Department of Civil Engineering, Laboratory of Building Construction and Physics, Aristotle University of Thessaloniki (A.U.Th.), Gr-541 24 Thessaloniki (Greece)

    2008-07-15

    The aim of this study is to determine how time lag and decrement factor are affected by wall orientation and exterior surface solar absorptivity, for specific climatic conditions. Their influence forms a non-sinusoidal periodical forcing function that simulates suitably the outdoor temperature fluctuations. This novel approach, allows the predictability of building's thermal response in an efficient way. The investigation is carried out for various insulated opaque wall formations comprising typical material elements, during the summer period in the mild Greek region. This study that allows proper building planning procedures, at the very early stages of the envelope design, presents great importance. The analysed configurations are assumed to have an orientation that corresponds to each compass point. In addition, the solar absorptivity of surface coatings is assumed to be varying from 0 to 1. The transient thermal analysis is obtained via a thermal circuit that models accurately the fundamental heat transfer mechanisms on both boundaries and through the multi-layered wall configurations. Moreover, the mathematical formulation and solution of this lumped model is achieved in discrete time steps by adopting the non-linear nodal method. The simulation results are focused on the single and combined effects of orientation and solar absorptivity on the dynamic thermal characteristics of various wall configurations. (author)

  11. Investigating the Flow and Biomechanics of the Embryonic Zebrafish Heart

    Science.gov (United States)

    Johnson, Brennan; Garrity, Deborah; Dasi, Lakshmi

    2010-11-01

    Understanding flow and kinematic characteristics of the embryonic heart is a prerequisite to devise early intervention or detection methods in the context of congenital heart defects. In this study, the kinematics and fluid dynamics of the embryonic zebrafish heart were analyzed through the early stages of cardiac development (24-48 hours post-fertilization) in vivo using optical microscopy and high-speed video. Endocardial walls and individual blood cells were segmented from raw images and were tracked through the cardiac cycle. Particle tracking velocimetry analysis yielded quantitative blood cell velocity field, chamber volume, and flow rate information. It was seen that the pumping mechanism starts as a combined peristaltic and suction pump while the heart is in the tube configuration and transforms into a positive displacement pump after cardiac looping. Strong two-phase nature of the fluid is evident. This work provides us new understanding of the spatio-temporal characteristics of kinematics and blood cell velocity field inside the developing heart.

  12. Intraventricular flow alterations due to dyssynchronous wall motion

    Science.gov (United States)

    Pope, Audrey M.; Lai, Hong Kuan; Samaee, Milad; Santhanakrishnan, Arvind

    2015-11-01

    Roughly 30% of patients with systolic heart failure suffer from left ventricular dyssynchrony (LVD), in which mechanical discoordination of the ventricle walls leads to poor hemodynamics and suboptimal cardiac function. There is currently no clear mechanistic understanding of how abnormalities in septal-lateral (SL) wall motion affects left ventricle (LV) function, which is needed to improve the treatment of LVD using cardiac resynchronization therapy. We use an experimental flow phantom with an LV physical model to study mechanistic effects of SL wall motion delay on LV function. To simulate mechanical LVD, two rigid shafts were coupled to two segments (apical and mid sections) along the septal wall of the LV model. Flow through the LV model was driven using a piston pump, and stepper motors coupled to the above shafts were used to locally perturb the septal wall segments relative to the pump motion. 2D PIV was used to examine the intraventricular flow through the LV physical model. Alterations to SL delay results in a reduction in the kinetic energy (KE) of the flow field compared to synchronous SL motion. The effect of varying SL motion delay from 0% (synchronous) to 100% (out-of-phase) on KE and viscous dissipation will be presented. This research was supported by the Oklahoma Center for Advancement of Science and Technology (HR14-022).

  13. Radiologic appearance of fat in the interatrial septum of the heart

    International Nuclear Information System (INIS)

    Szamosi, A.; Rajs, J.

    1979-01-01

    The interatrial septum of the heart may be visible on conventional films when it is oriented tangentially to the plane of the incident radiation, due to the presence of fatty tissue in the space between the muscular walls of the atria. (Auth.)

  14. Magnetic resonance imaging of the heart and great vessels

    International Nuclear Information System (INIS)

    Naitoh, Hiroaki; Nishimura, Tsunehiko; Takamiya, Makoto; Kozuka, Takahiro.

    1985-01-01

    About sixty subjects with normal heart or various cardiovascular diseases were examined with 0.35 or 1.5 T superconductive magnetic resonance imaging (MRI) system, and ECG-gated spin-echo multislice technique was used to evaluate cardiovascular anatomy. MRI accurately demonstrated ventricular wall thinning caused by myocardial infarction and asymmetric ventricular hypertrophy owing to cardiomyopathy. Rheumatic valvular thickening, congenital cardiac malformations, aortic aneurysm and dissection were also clearly demonstrated by gated MRI without the use of any contrast media. MRI was shown to be an excellent non-invasive imaging modality for evaluation of pathoanatomy of the heart and great vessels. (author)

  15. Simulating secondary organic aerosol in a regional air quality model using the statistical oxidation model – Part 2: Assessing the influence of vapor wall losses

    OpenAIRE

    Cappa, Christopher D.; Jathar, Shantanu H.; Kleeman, Michael J.; Docherty, Kenneth S.; Jimenez, Jose L.; Seinfeld, John H.; Wexler, Anthony S.

    2016-01-01

    The influence of losses of organic vapors to chamber walls during secondary organic aerosol (SOA) formation experiments has recently been established. Here, the influence of such losses on simulated ambient SOA concentrations and properties is assessed in the UCD/CIT regional air quality model using the statistical oxidation model (SOM) for SOA. The SOM was fit to laboratory chamber data both with and without accounting for vapor wall losses following the approa...

  16. Regional and ethnic differences among patients with heart failure in Asia: the Asian sudden cardiac death in heart failure registry.

    Science.gov (United States)

    Lam, Carolyn S P; Teng, Tiew-Hwa Katherine; Tay, Wan Ting; Anand, Inder; Zhang, Shu; Shimizu, Wataru; Narasimhan, Calambur; Park, Sang Weon; Yu, Cheuk-Man; Ngarmukos, Tachapong; Omar, Razali; Reyes, Eugene B; Siswanto, Bambang B; Hung, Chung-Lieh; Ling, Lieng H; Yap, Jonathan; MacDonald, Michael; Richards, A Mark

    2016-11-01

    To characterize regional and ethnic differences in heart failure (HF) across Asia. We prospectively studied 5276 patients with stable HF and reduced ejection fraction (≤40%) from 11 Asian regions (China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Taiwan, and Thailand). Mean age was 59.6 ± 13.1 years, 78.2% were men, and mean body mass index was 24.9 ± 5.1 kg/m 2 . Majority (64%) of patients had two or more comorbid conditions such as hypertension (51.9%), coronary artery disease (CAD, 50.2%), or diabetes (40.4%). The prevalence of CAD was highest in Southeast Asians (58.8 vs. 38.2% in Northeast Asians). Compared with Chinese ethnicity, Malays (adjusted odds ratio [OR] 1.97, 95% CI 1.63-2.38) and Indians (OR 1.44, 95% CI 1.24-1.68) had higher odds of CAD, whereas Koreans (OR 0.38, 95% CI 0.29-0.50) and Japanese (OR 0.44, 95% CI 0.36-0.55) had lower odds. The prevalence of hypertension and diabetes was highest in Southeast Asians (64.2 and 49.3%, respectively) and high-income regions (59.7 and 46.2%, respectively). There was significant interaction between ethnicity and region, where the adjusted odds were 3.95 (95% CI 2.51-6.21) for hypertension and 4.91 (95% CI 3.07-7.87) for diabetes among Indians from high- vs. low-income regions; and 2.60 (95% CI 1.66-4.06) for hypertension and 2.62 (95% CI 1.73-3.97) for diabetes among Malays from high- vs. low-income regions. These first prospective multi-national data from Asia highlight the significant heterogeneity among Asian patients with stable HF, and the important influence of both ethnicity and regional income level on patient characteristics. NCT01633398. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  17. Log-layer mismatch and modeling of the fluctuating wall stress in wall-modeled large-eddy simulations

    Science.gov (United States)

    Yang, Xiang I. A.; Park, George Ilhwan; Moin, Parviz

    2017-10-01

    Log-layer mismatch refers to a chronic problem found in wall-modeled large-eddy simulation (WMLES) or detached-eddy simulation, where the modeled wall-shear stress deviates from the true one by approximately 15 % . Many efforts have been made to resolve this mismatch. The often-used fixes, which are generally ad hoc, include modifying subgrid-scale stress models, adding a stochastic forcing, and moving the LES-wall-model matching location away from the wall. An analysis motivated by the integral wall-model formalism suggests that log-layer mismatch is resolved by the built-in physics-based temporal filtering. In this work we investigate in detail the effects of local filtering on log-layer mismatch. We show that both local temporal filtering and local wall-parallel filtering resolve log-layer mismatch without moving the LES-wall-model matching location away from the wall. Additionally, we look into the momentum balance in the near-wall region to provide an alternative explanation of how LLM occurs, which does not necessarily rely on the numerical-error argument. While filtering resolves log-layer mismatch, the quality of the wall-shear stress fluctuations predicted by WMLES does not improve with our remedy. The wall-shear stress fluctuations are highly underpredicted due to the implied use of LES filtering. However, good agreement can be found when the WMLES data are compared to the direct numerical simulation data filtered at the corresponding WMLES resolutions.

  18. Clinical evaluation of {sup 123}I-metaiodobenzylguanidine myocardial scintigram in patients with vascular heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Terada, Kouji; Sugihara, Hiroki; Shiga, Koji [Kyoto Prefectural Univ. of Medicine (Japan)] [and others

    1995-05-01

    Myocardial sympathetic nerve function can be evaluated by {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy. Congestive heart failure is closely related to myocardial sympathetic nerve function. This study evaluated the severity of congestive heart failure in 30 patients with valvular heart disease [aortic regurgitation (AR): n=20, mean age=70{+-}13 years; mitral regurgitation (MR): n=10, mean age=61{+-}18 years], who had chronic heart failure by MIBG myocardial scintigraphy. Single photon emission computed tomography (SPECT) and anterior planar myocardial images were obtained 15 minutes (initial images) and 4 hours (delayed images) after injection of MIBG (111 MBq). Defect score was determined by the delayed SPECT images visually as a semi-quantitative index. Myocardial MIBG uptake was quantified by the heart to upper mediastinum uptake ratio on the delayed anterior planar images (H/M) and mean cardiac MIBG washout rate during 4 hours was calculated from the bull`s eye display data (clearance). These indices were compared with the NYHA class and echocardiographic findings of the patients. MIBG regional defect in the delayed image was most frequently seen in the inferoposterior wall, and defect score and clearance were significantly higher and the H/M ratio was significantly lower in NYHA class III patients than in class II patients. In patients with AR, clearance significantly correlated with left ventricular end-systolic dimension. In patients with MR, both the H/M ratio and clearance significantly correlated with left atrial dimension. Defect score, H/M, and clearance were closely related to the severity of AR and MR. These results indicate that MIBG scan can be used to assess the severity of valvular heart disease. (author).

  19. A film-based wall shear stress sensor for wall-bounded turbulent flows

    Science.gov (United States)

    Amili, Omid; Soria, Julio

    2011-07-01

    In wall-bounded turbulent flows, determination of wall shear stress is an important task. The main objective of the present work is to develop a sensor which is capable of measuring surface shear stress over an extended region applicable to wall-bounded turbulent flows. This sensor, as a direct method for measuring wall shear stress, consists of mounting a thin flexible film on the solid surface. The sensor is made of a homogeneous, isotropic, and incompressible material. The geometry and mechanical properties of the film are measured, and particles with the nominal size of 11 μm in diameter are embedded on the film's surface to act as markers. An optical technique is used to measure the film deformation caused by the flow. The film has typically deflection of less than 2% of the material thickness under maximum loading. The sensor sensitivity can be adjusted by changing the thickness of the layer or the shear modulus of the film's material. The paper reports the sensor fabrication, static and dynamic calibration procedure, and its application to a fully developed turbulent channel flow at Reynolds numbers in the range of 90,000-130,000 based on the bulk velocity and channel full height. The results are compared to alternative wall shear stress measurement methods.

  20. Sequential biventricular pacing improves regional contractility, longitudinal function and dyssynchrony in patients with heart failure and prolonged QRS

    Directory of Open Access Journals (Sweden)

    Ring Margareta

    2010-04-01

    Full Text Available Abstract Aims Biventricular pacing (BiP is an effective treatment in systolic heart failure (HF patients with prolonged QRS. However, approximately 35% of the patients receiving BiP are classified as non-responders. The aim of this study is to evaluate the acute effects of VV-optimization on systolic heart function. Methods Twenty-one HF patients aged 72 (46-88 years, QRS 154 (120-190 ms, were studied with echocardiography, Tissue Doppler Imaging (TDI and 3D-echo the first day after receiving a BiP device. TDI was performed; during simultaneous pacing (LV-lead pacing 4 ms before the RV-lead and during sequential pacing (LV 20 and 40 ms before RV and RV 20 and 40 ms before LV-lead pacing. Systolic heart function was studied by tissue tracking (TT for longitudinal function and systolic maximal velocity (SMV for regional contractility and signs of dyssynchrony assessed by time-delays standard deviation of aortic valve opening to SMV, AVO-SMV/SD and tissue synchronization imaging (TSI. Results The TT mean value preoperatively was 4,2 ± 1,5 and increased at simultaneous pacing to 5,0 ± 1,2 mm (p Conclusions VV-optimization in the acute phase improves systolic heart function more than simultaneous BiP pacing. Long-term effects should be evaluated in prospective randomized trials.

  1. Silencing of the Drosophila ortholog of SOX5 in heart leads to cardiac dysfunction as detected by optical coherence tomography.

    Science.gov (United States)

    Li, Airong; Ahsen, Osman O; Liu, Jonathan J; Du, Chuang; McKee, Mary L; Yang, Yan; Wasco, Wilma; Newton-Cheh, Christopher H; O'Donnell, Christopher J; Fujimoto, James G; Zhou, Chao; Tanzi, Rudolph E

    2013-09-15

    The SRY-related HMG-box 5 (SOX5) gene encodes a member of the SOX family of transcription factors. Recently, genome-wide association studies have implicated SOX5 as a candidate gene for susceptibility to four cardiac-related endophenotypes: higher resting heart rate (HR), the electrocardiographic PR interval, atrial fibrillation and left ventricular mass. We have determined that human SOX5 has a highly conserved Drosophila ortholog, Sox102F, and have employed transgenic Drosophila models to quantitatively measure cardiac function in adult flies. For this purpose, we have developed a high-speed and ultrahigh-resolution optical coherence tomography imaging system, which enables rapid cross-sectional imaging of the heart tube over various cardiac cycles for the measurement of cardiac structural and dynamical parameters such as HR, dimensions and areas of heart chambers, cardiac wall thickness and wall velocities. We have found that the silencing of Sox102F resulted in a significant decrease in HR, heart chamber size and cardiac wall velocities, and a significant increase in cardiac wall thickness that was accompanied by disrupted myofibril structure in adult flies. In addition, the silencing of Sox102F in the wing led to increased L2, L3 and wing marginal veins and increased and disorganized expression of wingless, the central component of the Wnt signaling pathway. Collectively, the silencing of Sox102F resulted in severe cardiac dysfunction and structural defects with disrupted Wnt signaling transduction in flies. This implicates an important functional role for SOX5 in heart and suggests that the alterations in SOX5 levels may contribute to the pathogenesis of multiple cardiac diseases or traits.

  2. Cardiac pacing in heart failure patients with left bundle branch block: impact of pacing site for optimizing left ventricular resynchronization.

    Science.gov (United States)

    Pappone, C; Rosanio, S; Oreto, G; Tocchi, M; Gulletta, S; Salvati, A; Dicandia, C; Santinelli, V; Mazzone, P; Veglia, F; Ding, J; Sallusti, L; Spinelli, J; Vicedomini, G

    2000-07-01

    Acute left ventricular pacing has been associated with hemodynamic improvement in patients with congestive heart failure and wide QRS complex. We hypothesized that pacing two left ventricular sites simultaneously would produce faster activation and better systolic function than single-site pacing. We selected 14 heart failure patients (NYHA functional class III or IV) in normal sinus rhythm with left bundle branch block and QRS > 150 ms. An 8F dual micromanometer catheter was placed in the aorta for measuring +dP/dt (mmHg/s), aortic pulse pressure (mmHg), and end-diastolic pressure (mmHg). Pacing leads were positioned via coronary veins at the posterior base and lateral wall. Patients were acutely paced VDD at the posterior base, lateral wall, and both sites (dual-site) with 5 atrioventricular delays (from 8 ms to PR -30 ms). Pacing sequences were executed in randomized order using a custom external computer (FlexStim, Guidant CRM). Dual-site pacing increased peak +dP/dt significantly more than posterior base and lateral wall pacing. Dual-site and posterior base pacing raised aortic pulse pressure significantly more than lateral wall pacing. Dual-site pacing shortened QRS duration by 22 %, whereas posterior base and lateral wall pacing increased it by 2 and 12%, respectively (p = 0.006). In heart failure patients with left bundle branch block, dual-site pacing improves systolic function more than single-site stimulation. Improved ventricular activation synchrony, expressed by paced QRS narrowing, may account for the additional benefit of dual- vs single-site pacing in enhancing contractility. This novel approach deserves consideration for future heart failure pacing studies.

  3. Spanwise vorticity and wall normal velocity structure in the inertial region of turbulent boundary layers

    Science.gov (United States)

    Cuevas Bautista, Juan Carlos; Morrill-Winter, Caleb; White, Christopher; Chini, Gregory; Klewicki, Joseph

    2017-11-01

    The Reynolds shear stress gradient is a leading order mechanism on the inertial domain of turbulent wall-flows. This quantity can be described relative to the sum of two velocity-vorticity correlations, vωz and wωy . Recent studies suggest that the first of these correlates with the step-like structure of the instantaneous streamwise velocity profile on the inertial layer. This structure is comprised of large zones of uniform momentum segregated by slender regions of concentrated vorticity. In this talk we study the contributions of the v and ωz motions to the vorticity transport (vωz) mechanism through the use of experimental data at large friction Reynolds numbers, δ+. The primary contributions to v and ωz were estimated by identifying the peak wavelengths of their streamwise spectra. The magnitudes of these peaks are of the same order, and are shown to exhibit a weak δ+ dependence. The peak wavelengths of v, however, exhibit a strong wall-distance (y) dependence, while the peak wavelengths of ωz show only a weak y dependence, and remain almost O (√{δ+}) in size throughout the inertial domain. This research was partially supported by the National Science Foundation and partially supported by the Australian Research Council.

  4. An NPARC Turbulence Module with Wall Functions

    Science.gov (United States)

    Zhu, J.; Shih, T.-H.

    1997-01-01

    The turbulence module recently developed for the NPARC code has been extended to include wall functions. The Van Driest transformation is used so that the wall functions can be applied to both incompressible and compressible flows. The module is equipped with three two-equation K-epsilon turbulence models: Chien, Shih-Lumley and CMOTR models. Details of the wall functions as well as their numerical implementation are reported. It is shown that the inappropriate artificial viscosity in the near-wall region has a big influence on the solution of the wall function approach. A simple way to eliminate this influence is proposed, which gives satisfactory results during the code validation. The module can be easily linked to the NPARC code for practical applications.

  5. Cardiac dose reduction with deep inspiration breath hold for left-sided breast cancer radiotherapy patients with and without regional nodal irradiation.

    Science.gov (United States)

    Yeung, Rosanna; Conroy, Leigh; Long, Karen; Walrath, Daphne; Li, Haocheng; Smith, Wendy; Hudson, Alana; Phan, Tien

    2015-09-22

    Deep inspiration breath hold (DIBH) reduces heart and left anterior descending artery (LAD) dose during left-sided breast radiation therapy (RT); however there is limited information about which patients derive the most benefit from DIBH. The primary objective of this study was to determine which patients benefit the most from DIBH by comparing percent reduction in mean cardiac dose conferred by DIBH for patients treated with whole breast RT ± boost (WBRT) versus those receiving breast/chest wall plus regional nodal irradiation, including internal mammary chain (IMC) nodes (B/CWRT + RNI) using a modified wide tangent technique. A secondary objective was to determine if DIBH was required to meet a proposed heart dose constraint of Dmean irradiation.

  6. Transient forced convection with viscous dissipation to power-law fluids in thermal entrance region of circular ducts with constant wall heat flux

    International Nuclear Information System (INIS)

    Dehkordi, Asghar Molaei; Mohammadi, Ali Asghar

    2009-01-01

    A numerical investigation was conducted on the transient behavior of a hydrodynamically, fully developed, laminar flow of power-law fluids in the thermally developing entrance region of circular ducts taking into account the effect of viscous dissipation but neglecting the effect of axial conduction. In this regard, the unsteady state thermal energy equation was solved by using a finite difference method, whereas the steady state thermal energy equation without wall heat flux was solved analytically as the initial condition of the former. The effects of the power-law index and wall heat flux on the local Nusselt number and thermal entrance length were investigated. Moreover, the local Nusselt number of steady state conditions was correlated in terms of the power-law index and wall heat flux and compared with literature data, which were obtained by an analytic solution for Newtonian fluids. Furthermore, a relationship was proposed for the thermal entrance length

  7. On a turbulent wall model to predict hemolysis numerically in medical devices

    Science.gov (United States)

    Lee, Seunghun; Chang, Minwook; Kang, Seongwon; Hur, Nahmkeon; Kim, Wonjung

    2017-11-01

    Analyzing degradation of red blood cells is very important for medical devices with blood flows. The blood shear stress has been recognized as the most dominant factor for hemolysis in medical devices. Compared to laminar flows, turbulent flows have higher shear stress values in the regions near the wall. In case of predicting hemolysis numerically, this phenomenon can require a very fine mesh and large computational resources. In order to resolve this issue, the purpose of this study is to develop a turbulent wall model to predict the hemolysis more efficiently. In order to decrease the numerical error of hemolysis prediction in a coarse grid resolution, we divided the computational domain into two regions and applied different approaches to each region. In the near-wall region with a steep velocity gradient, an analytic approach using modeled velocity profile is applied to reduce a numerical error to allow a coarse grid resolution. We adopt the Van Driest law as a model for the mean velocity profile. In a region far from the wall, a regular numerical discretization is applied. The proposed turbulent wall model is evaluated for a few turbulent flows inside a cannula and centrifugal pumps. The results present that the proposed turbulent wall model for hemolysis improves the computational efficiency significantly for engineering applications. Corresponding author.

  8. Study of noise reduction characteristics of double-wall panels

    Science.gov (United States)

    Navaneethan, R.; Quayle, B.; Stevenson, S.; Graham, M.

    1983-05-01

    The noise reduction characteristics of general aviation type, flat, double-wall structures were investigated. The experimental study was carried out on 20-by-20 inch panels with an exposed area of 18 by 18 inches. A frequency range from 20 to 5000 Hz was covered. The experimental results, in general, follow the expected trends. At low frequencies the double-wall structures are no better than the single-wall structures. However, for depths normally used in the general aviation industry, the double-wall panels are very attractive. The graphite-spoxy skin panels have higher noise reduction at very low frequencies ( 100 Hz) than the Kevlar skin panels. But the aluminum panels have higher noise reduction in the high frequency region, due to their greater mass. Use of fiberglass insulation is not effective in the low frequency region, and at times it is even negative. But the insulation is effective in the high-frequency region. The theoretical model for predicting the transmission loss of these multilayered panels is also discussed.

  9. DNA methylation abnormalities in congenital heart disease.

    Science.gov (United States)

    Serra-Juhé, Clara; Cuscó, Ivon; Homs, Aïda; Flores, Raquel; Torán, Núria; Pérez-Jurado, Luis A

    2015-01-01

    Congenital heart defects represent the most common malformation at birth, occurring also in ∼50% of individuals with Down syndrome. Congenital heart defects are thought to have multifactorial etiology, but the main causes are largely unknown. We have explored the global methylation profile of fetal heart DNA in comparison to blood DNA from control subjects: an absolute correlation with the type of tissue was detected. Pathway analysis revealed a significant enrichment of differential methylation at genes related to muscle contraction and cardiomyopathies in the developing heart DNA. We have also searched for abnormal methylation profiles on developing heart-tissue DNA of syndromic and non-syndromic congenital heart defects. On average, 3 regions with aberrant methylation were detected per sample and 18 regions were found differentially methylated between groups. Several epimutations were detected in candidate genes involved in growth regulation, apoptosis and folate pathway. A likely pathogenic hypermethylation of several intragenic sites at the MSX1 gene, involved in outflow tract morphogenesis, was found in a fetus with isolated heart malformation. In addition, hypermethylation of the GATA4 gene was present in fetuses with Down syndrome with or without congenital heart defects, as well as in fetuses with isolated heart malformations. Expression deregulation of the abnormally methylated genes was detected. Our data indicate that epigenetic alterations of relevant genes are present in developing heart DNA in fetuses with both isolated and syndromic heart malformations. These epimutations likely contribute to the pathogenesis of the malformation by cis-acting effects on gene expression.

  10. Dynamics of strings between walls

    International Nuclear Information System (INIS)

    Eto, Minoru; Fujimori, Toshiaki; Nagashima, Takayuki; Nitta, Muneto; Ohashi, Keisuke; Sakai, Norisuke

    2009-01-01

    Configurations of vortex strings stretched between or ending on domain walls were previously found to be 1/4 Bogomol'nyi-Prasad-Sommerfield (BPS) states in N=2 supersymmetric gauge theories in 3+1 dimensions. Among zero modes of string positions, the center of mass of strings in each region between two adjacent domain walls is shown to be non-normalizable whereas the rests are normalizable. We study dynamics of vortex strings stretched between separated domain walls by using two methods, the moduli space (geodesic) approximation of full 1/4 BPS states and the charged particle approximation for string end points in the wall effective action. In the first method we explicitly obtain the effective Lagrangian in the strong coupling limit, which is written in terms of hypergeometric functions, and find the 90 deg. scattering for head-on collision. In the second method the domain wall effective action is assumed to be U(1) N gauge theory, and we find a good agreement between two methods for well-separated strings.

  11. Growth hormone and the heart.

    Science.gov (United States)

    Cittadini, A; Longobardi, S; Fazio, S; Saccà, L

    1999-01-01

    Until a few years ago, growth hormone (GH) and insulin-like growth factor-1 (IGF-1) were considered essential only to the control of linear growth, glucose homeostasis, and for the maintenance of skeletal muscle mass. A large body of evidence recently coming from animal and human studies has unequivocally proven that the heart is a target organ for the GH/IGF-1 axis. Specifically GH exerts both direct and indirect cardiovascular actions. Among the direct effects, the ability of GH to trigger cardiac tissue growth plays a pivotal role. Another direct effect is to augment cardiac contractility, independent of myocardial growth. Direct effects of GH also include the improvement of myocardial energetics and mechanical efficiency. Indirect effects of GH on the heart include decreased peripheral vascular resistance (PVR), expansion of blood volume, increased glomerular filtration rate, enhanced respiratory activity, increased skeletal muscle performance, and psychological well-being. Among them, the most consistently found is the decrease of PVR. GH may also raise preload through its sodium-retaining action and its interference with the hormonal system that regulates water and electrolyte metabolism. Particularly important is the effect of GH on skeletal muscle mass and performance. Taking into account that heart failure is characterized by left ventricular dilation, reduced cardiac contractility, and increase of wall stress and peripheral vascular resistance, GH may be beneficial for treatment of heart failure. Animal studies and preliminary human trials have confirmed the validity of the GH approach to the treatment of heart failure. Larger placebo-controlled human studies represent the main focus of future investigations.

  12. Reynold-Number Effects on Near-Wall Turbulence

    Science.gov (United States)

    Mansour, N. N.; Kim, J.; Moser, R. D.; Rai, Man Mohan (Technical Monitor)

    1995-01-01

    The Reynolds stress budget in a full developed turbulent channel flow for three Reynolds numbers (Re = 180,395,590) are used to investigate the near wall scaling of various turbulence quantities. We find that as the Reynolds number increases, the extent of the region where the production of the kinetic energy is equal to the dissipation increases. At the highest Reynolds number the region of equilibrium extends from y+ - 120 to y+ = 240. As the Reynolds number increases, we find that wall scaling collapses the budgets for the streamwise fluctuating component, but the budgets for the other two components show Reynolds number dependency.

  13. Changes During Growth in Cell Wall Components of Berseem Clover Under Different Cutting Treatments in a Mediterranean Region

    Directory of Open Access Journals (Sweden)

    Giuditta De Santis

    2007-09-01

    Full Text Available Forage digestibility of berseem clover (Trifolium Alexandrinum L. is influenced by plant cell wall composition. This study was conducted to evaluate the effects of different cutting treatments on cell-wall components of the herbage and plant fractions in two Mediterranean berseem genotypes during growth and to examine the relationship between digestibility and cell wall components in these plant fractions. Cutting treatments were initiated at sixth internode elongation (A and early flowering (B and there was an uncut control treatment (C. Spring growth of genotypes of Egyptian (cv. Giza 10 and Italian (cv. Sacromonte origins was harvested in each of two years beginning 196 days after sowing and thereafter every 6 days (twelve harvests in total to measure cell wall components. Neutral detergent fibre (NDF, acid detergent fibre (ADF and acid detergent lignin (ADL concentrations were determined for leaf, stem, and total forage of each cultivar at each harvest. Without defoliation, NDF, ADF and ADL concentrations of herbage increased linearly to a maximum of 528, 375 and 84 g kg-1 DM, respectively, by 220 days after planting, when plant height reached maximum values, then plateaued until 257 days after planting. Plant parts differed in cell-wall concentration, with stems being of higher fibre components than leaves, in the two cutting treatments. Herbage and plant fraction fibre concentrations were negatively correlated with digestibility for all cutting treatments. Defoliation induced a reduction in fibre concentrations and plant height, although a rapid regrowth was observed after cutting, in both treatments A and B. However, delaying defoliation to the early flowering stage (B increased fibre components concentrations both at cutting time and during the growing season and significantly reduced the regrowth height. Conversely, plants cut at the sixth internode elongation (treatment A showed lower concentrations of fibre fractions than initiating

  14. Assessment of the interface of beating heart with total artificial heart using magnetic resonance imaging

    International Nuclear Information System (INIS)

    Komoda, Tsuyoshi; Maeta, Hajime; Uyama, Chikao; Sanou, Kazuo.

    1992-01-01

    We have studied three-dimensionally (3-D) reconstructed images of atrioventricular (AV) annuli based on four-chamber magnetic resonance (MR) images for total artificial heart (TAH) implantation. To assess the interrelationship among the AV annuli and the thorax, we applied the frame of reference of the vertebral canal to these images. The Z-axis was along the vertebral canal, the Y-axis in the anteroposterior direction. The angle alpha was defined as the angle between the X-axis and the intersection between the plane of the annulus and the X-Y plane. The angle beta was defined as the angle between the Z-axis and the intersection between the plane of annulus and X-Z plane. The angle gamma was defined as the angle between the plane of the annulus and the anterior thoracic wall. We determined each angle for the mitral annulus (MVA) and tricuspid annulus (TVA) in four normal subjects to be as follows: alpha-MVA, 20.5-39.5 degrees; alpha-TVA, 26.1-43.5 degrees; beta-MVA, 4.7-49.4 degrees; beta-TVA, 4.4-40.9 degrees; and gamma-TVA, 35.2-44.1 degrees. It is suggested that reconstruction of the thoracic wall and AV annuli using the frame of reference of the diaphragmatic surface of the heart would facilitate evaluation of the spacial requirements for TAH implantation. Research to define this new frame of reference is in progress. (author)

  15. Influence of Coherent Structures on the Wall Shear Stress in Axial Flow Between a Cylinder and a Plane Wall

    International Nuclear Information System (INIS)

    Khabbouchi, Imed; Guellouz, Mohamed Sadok; Tavoularis, Stavros

    2009-01-01

    Synchronised hot-film and hot-wire measurements were made in the narrower region of a rectangular channel containing a cylindrical rod. The hot-film probe was mounted flush with the channel bottom wall to measure the wall shear stress, while the hot-wire probe was placed at a fixed position, selected in order to easily detect the passage of coherent structures. Mean and rms profiles of the wall shear stress show the influence of the gap to diameter ratio on their respective distributions. The latter presented peculiarities that could only be explained by the presence of coherent structures in the flow between the rod and the wall. Evidence of this presence is seen in the velocity power spectra. The strong influence of the coherent structures on the wall shear stress spatial and temporal distributions is established through velocity-wall shear stress cross-correlations functions and through conditionally sampled measurements

  16. Quantification and Control of Wall Effects in Porous Media Experiments

    Science.gov (United States)

    Roth, E. J.; Mays, D. C.; Neupauer, R.; Crimaldi, J. P.

    2017-12-01

    Fluid flow dynamics in porous media are dominated by media heterogeneity. This heterogeneity can create preferential pathways in which local seepage velocities dwarf system seepage velocities, further complicating an already incomplete understanding of dispersive processes. In physical models of porous media flows, apparatus walls introduce preferential flow paths (i.e., wall effects) that may overwhelm other naturally occurring preferential pathways within the apparatus, leading to deceptive results. We used planar laser-induced fluorescence (PLIF) in conjunction with refractive index matched (RIM) porous media and pore fluid to observe fluid dynamics in the porous media, with particular attention to the region near the apparatus walls in a 17 cm x 8 cm x 7 cm uniform flow cell. Hexagonal close packed spheres were used to create an isotropic, homogenous porous media field in the interior of the apparatus. Visualization of the movement of a fluorescent dye revealed the influence of the wall in creating higher permeability preferential flow paths in an otherwise homogenous media packing. These preferential flow paths extended approximately one half of one sphere diameter from the wall for homogenously packed regions, with a quickly diminishing effect on flow dynamics for homogenous media adjacent to the preferential pathway, but with major influence on flow dynamics for adjoining heterogeneous regions. Multiple approaches to mitigate wall effects were investigated, and a modified wall was created such that the fluid dynamics near the wall mimics the fluid dynamics within the homogenous porous media. This research supports the design of a two-dimensional experimental apparatus that will simulate engineered pumping schemes for use in contaminant remediation. However, this research could benefit the design of fixed bed reactors or other engineering challenges in which vessel walls contribute to unwanted preferential flow.

  17. Non-invasive evaluation of regional function of the left ventricle

    International Nuclear Information System (INIS)

    Schad, N.; Nickel, O.

    1980-01-01

    Assessment of regional left ventricular function with first pass angiocardiography in the RAO view almost entirely depends on high image statistics, accurate border definition and background subtraction, as well as an analysis of so called functional images which regionally measure and illustrate functional change during heart action. During first bolus transit the multicrystal camera gives an average of 300,000 cts/sec allowing precise border definition because of steepness of count changes at the LV-border. A varying background adjacent to each border point and also over the LV is subtracted. Measurements of segmental hemiaxis shortening and of zonal ejection fractions in the three zones supplied by the major coronary arteries have been performed. Clinical applications comprise examinations at rest, peak exercise, after nitroglycerin administration and after bypass graft surgery. Wall motion measured by means of hemiaxis shortening (210 segments) showed good correlation with angiocardiography in 91% of segments with normokinesis, in 90% asynergic and 88% of hypokinetic segments. Functional images corrected false negativ and false positiv wall motion measurements. In patients after myocardial infarction, there was (after NTG-administration) a significant increase in hemiaxis shortening in asynergic segment, but not in dyskinesias. Exercise studies in patients with wall motion disorders showed a significantly higher increase in global ejection fraction in patients with resting EF-values and 58% than above that value. Zonal ejection fractions after bypass surgery showed an average increase of 6.4 points if complete vascularization was performed, but no zonal increase or decrease when vascularization was incomplete or the zone included a previous myocardial infarction. (orig.) [de

  18. Self-similarity in the inertial region of wall turbulence.

    Science.gov (United States)

    Klewicki, J; Philip, J; Marusic, I; Chauhan, K; Morrill-Winter, C

    2014-12-01

    The inverse of the von Kármán constant κ is the leading coefficient in the equation describing the logarithmic mean velocity profile in wall bounded turbulent flows. Klewicki [J. Fluid Mech. 718, 596 (2013)] connects the asymptotic value of κ with an emerging condition of dynamic self-similarity on an interior inertial domain that contains a geometrically self-similar hierarchy of scaling layers. A number of properties associated with the asymptotic value of κ are revealed. This is accomplished using a framework that retains connection to invariance properties admitted by the mean statement of dynamics. The development leads toward, but terminates short of, analytically determining a value for κ. It is shown that if adjacent layers on the hierarchy (or their adjacent positions) adhere to the same self-similarity that is analytically shown to exist between any given layer and its position, then κ≡Φ(-2)=0.381966..., where Φ=(1+√5)/2 is the golden ratio. A number of measures, derived specifically from an analysis of the mean momentum equation, are subsequently used to empirically explore the veracity and implications of κ=Φ(-2). Consistent with the differential transformations underlying an invariant form admitted by the governing mean equation, it is demonstrated that the value of κ arises from two geometric features associated with the inertial turbulent motions responsible for momentum transport. One nominally pertains to the shape of the relevant motions as quantified by their area coverage in any given wall-parallel plane, and the other pertains to the changing size of these motions in the wall-normal direction. In accord with self-similar mean dynamics, these two features remain invariant across the inertial domain. Data from direct numerical simulations and higher Reynolds number experiments are presented and discussed relative to the self-similar geometric structure indicated by the analysis, and in particular the special form of self

  19. Purification and characterization of a soybean cell wall protein

    International Nuclear Information System (INIS)

    San Francisco, S.; Tierney, M.L.

    1989-01-01

    Plant cell wall composition is thought to reflect cellular responses to developmental and environmental signals. We have purified a 33 kDa protein from cell wall extracts of soybean seedlings which is most abundant in extracts from the hook region of the hypocotyl and is rich in proline and hydroxypyroline. In vivo 3 H-proline labelling of hypocotyl tissues indicates that the hook tissue is the predominant site for synthesis of this protein. In unwounded hook, label is incorporated into a 33 kDa protein, while in wounded hook this and additional proteins rich in proline are synthesized. Similarly treated cell wall extracts analyzed by Western blot analysis, using a polyclonal antibody raised against this 33kD protein, showed that the 33 kDa protein is most abundant in cell wall extracts from the hook region of unwounded seedlings and does not increase upon wounding. An immunologically related 35kD protein is also apparent in extracts from wounded hooks and appears to co-migrate with one of the labelled proteins extractable from this tissue. These data indicate that there are two related, proline-rich cell wall proteins in the hook region of soybean seedlings, one of which (33 kDa) is prominent during seedling development and another (35 kDa) which is wound inducible

  20. Reduced expression of mitochondrial electron transport chain proteins from hibernating hearts relative to ischemic preconditioned hearts in the second window of protection.

    Science.gov (United States)

    Cabrera, Jesús A; Butterick, Tammy A; Long, Eric K; Ziemba, Elizabeth A; Anderson, Lorraine B; Duffy, Cayla M; Sluiter, Willem; Duncker, Dirk J; Zhang, Jianyi; Chen, Yingjie; Ward, Herbert B; Kelly, Rosemary F; McFalls, Edward O

    2013-07-01

    Although protection against necrosis has been observed in both hibernating (HIB) and ischemic preconditioned hearts in the second window of protection (SWOP), a comparison of the mitochondrial proteome between the two entities has not been previously performed. Anesthetized swine underwent instrumentation with a fixed constrictor around the LAD artery and were followed for 12 weeks (HIB; N=7). A second group of anesthetized swine underwent ischemic preconditioning by inflating a balloon within the LAD artery 10 times for 2 min, each separated by 2 min reperfusion and were sacrificed 24h later (SWOP; N=7). Myocardial blood flow and high-energy nucleotides were obtained in the LAD region and normalized to remote regions. Post-sacrifice, protein content as measured with iTRAQ was compared in isolated mitochondria from the LAD area of a Sham heart. Basal regional blood flow in the LAD region when normalized to the remote region was 0.86±0.04 in HIB and 1.02±0.02 in SWOP tissue (Pregional blood flows in HIB hearts, ATP content in the LAD region, when normalized to the remote region was similar in HIB versus SWOP (1.06±0.06 and 1.02±0.05 respectively; NS) as was the transmural phosphocreatine (PCr) to ATP ratio (2.1±0.2 and 2.2±0.2 respectively; NS). Using iTRAQ, 64 common proteins were identified in HIB and SWOP hearts. Compared with SWOP, the relative abundance of mitochondrial proteins involved with electron transport chain (ETC) were reduced in HIB including NADH dehydrogenase, Cytochrome c reductase and oxidase, ATP synthase, and nicotinamide nucleotide transhydrogenase. Within chronically HIB heart tissue with reduced blood flow, the relative abundance of mitochondrial ETC proteins is decreased when compared with SWOP tissue. These data support the concept that HIB heart tissue subjected to chronically reduced blood flow is associated with a down-regulation in the expression of key mitochondrial proteins involved in electron transport. Published by Elsevier

  1. Dominance of free wall radial motion in global right ventricular function of heart transplant recipients.

    Science.gov (United States)

    Lakatos, Bálint Károly; Tokodi, Márton; Assabiny, Alexandra; Tősér, Zoltán; Kosztin, Annamária; Doronina, Alexandra; Rácz, Kristóf; Koritsánszky, Kinga Bianka; Berzsenyi, Viktor; Németh, Endre; Sax, Balázs; Kovács, Attila; Merkely, Béla

    2018-03-01

    Assessment of right ventricular (RV) function using conventional echocardiography might be inadequate as the radial motion of the RV free wall is often neglected. Our aim was to quantify the longitudinal and the radial components of RV function using three-dimensional (3D) echocardiography in heart transplant (HTX) recipients. Fifty-one HTX patients in stable cardiovascular condition without history of relevant rejection episode or chronic allograft vasculopathy and 30 healthy volunteers were enrolled. RV end-diastolic (EDV) volume and total ejection fraction (TEF) were measured by 3D echocardiography. Furthermore, we quantified longitudinal (LEF) and radial ejection fraction (REF) by decomposing the motion of the RV using the ReVISION method. RV EDV did not differ between groups (HTX vs control; 96 ± 27 vs 97 ± 2 mL). In HTX patients, TEF was lower, however, tricuspid annular plane systolic excursion (TAPSE) decreased to a greater extent (TEF: 47 ± 7 vs 54 ± 4% [-13%], TAPSE: 11 ± 5 vs 21 ± 4 mm [-48%], P < .0001). In HTX patients, REF/TEF ratio was significantly higher compared to LEF/TEF (REF/TEF vs LEF/TEF: 0.58 ± 0.10 vs 0.27 ± 0.08, P < .0001), while in controls the REF/TEF and LEF/TEF ratio was similar (0.45 ± 0.07 vs 0.47 ± 0.07). Current results confirm the superiority of radial motion in determining RV function in HTX patients. Parameters incorporating the radial motion are recommended to assess RV function in HTX recipients. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Conceptual design of the INTOR first-wall system

    International Nuclear Information System (INIS)

    Smith, D.L.; Majumdar, S.; Mattas, R.F.; Turner, L.; Jung, J.; Abdou, M.A.; Bowers, D.; Trachsel, C.; Merrill, B.

    1981-10-01

    The design concept and performance characteristics of the first-wall design for the phase-1 INTOR (International Tokamak Reactor) study is described. The reference design consists of a water-cooled stainless steel panel. The major uncertainty regarding the performance of the bare stainless steel wall relates to the response of a thin-melt layer predicted to form on limited regions during a plasma disruption. A more-complex backup design, which incorporates radiatively cooled graphite tiles on the inboard wall, is briefly described

  3. In vivo hypertensive arterial wall uptake of radiolabeled liposomes

    International Nuclear Information System (INIS)

    Hodis, H.N.; Amartey, J.K.; Crawford, D.W.; Wickham, E.; Blankenhorn, D.H.

    1990-01-01

    Using five sham-operated and seven aortic coarctation-induced hypertensive New Zealand White rabbits intravenously injected with neutral small unilamellar vesicles loaded with [111In]nitrilotriacetic acid, we demonstrated in vivo that the normal aortic arterial wall participates in liposome uptake and that this uptake is increased in the hypertensive aortic wall by approximately threefold (p less than or equal to 0.0001). Among the three regions examined, aortic arch, thoracic aorta, and lower abdominal aorta, the difference in uptake between the normotensive and hypertensive arterial walls was significantly different, p less than or equal to 0.05, p less than or equal to 0.0001, and p less than 0.05, respectively. The uptake by the different regions of the hypertensive arterial wall is consistent with the pathological changes present in these areas. Furthermore, the extent of liposome uptake by the aortic wall is strongly correlated with the height of the blood pressure (r = 0.85, p = 0.001, n = 11). We conclude that neutral small unilamellar liposomes can be used to carry agents into the arterial wall in vivo in the study of hypertensive vascular disease and could be especially useful for the delivery of pharmacologically or biologically active agents that would otherwise be inactivated within the circulation or are impermeable to the arterial wall

  4. μCT of ex-vivo stained mouse hearts and embryos enables a precise match between 3D virtual histology, classical histology and immunochemistry

    Science.gov (United States)

    Larsson, Emanuel; Martin, Sabine; Lazzarini, Marcio; Tromba, Giuliana; Missbach-Guentner, Jeannine; Pinkert-Leetsch, Diana; Katschinski, Dörthe M.; Alves, Frauke

    2017-01-01

    The small size of the adult and developing mouse heart poses a great challenge for imaging in preclinical research. The aim of the study was to establish a phosphotungstic acid (PTA) ex-vivo staining approach that efficiently enhances the x-ray attenuation of soft-tissue to allow high resolution 3D visualization of mouse hearts by synchrotron radiation based μCT (SRμCT) and classical μCT. We demonstrate that SRμCT of PTA stained mouse hearts ex-vivo allows imaging of the cardiac atrium, ventricles, myocardium especially its fibre structure and vessel walls in great detail and furthermore enables the depiction of growth and anatomical changes during distinct developmental stages of hearts in mouse embryos. Our x-ray based virtual histology approach is not limited to SRμCT as it does not require monochromatic and/or coherent x-ray sources and even more importantly can be combined with conventional histological procedures. Furthermore, it permits volumetric measurements as we show for the assessment of the plaque volumes in the aortic valve region of mice from an ApoE-/- mouse model. Subsequent, Masson-Goldner trichrome staining of paraffin sections of PTA stained samples revealed intact collagen and muscle fibres and positive staining of CD31 on endothelial cells by immunohistochemistry illustrates that our approach does not prevent immunochemistry analysis. The feasibility to scan hearts already embedded in paraffin ensured a 100% correlation between virtual cut sections of the CT data sets and histological heart sections of the same sample and may allow in future guiding the cutting process to specific regions of interest. In summary, since our CT based virtual histology approach is a powerful tool for the 3D depiction of morphological alterations in hearts and embryos in high resolution and can be combined with classical histological analysis it may be used in preclinical research to unravel structural alterations of various heart diseases. PMID:28178293

  5. Assessing forest resources in Denmark using wall-to-wall remote sensing data

    DEFF Research Database (Denmark)

    Schumacher, Johannes

    then be applied to estimate resources on both small and large scales. Numerous studies have investigated the possibilities of using remote sensing data for forest monitoring at plot or single tree levels. However, experience of estimating these properties for larger areas, for example regional or country...... assessments, is lacking. In this thesis wall-to-wall remote sensing data (from aerial images, airborne LiDAR, and space-borne SAR) were combined with ground reference data (from NFI plots and tree species experiments) to build and evaluate models estimating properties such as basal area, timber volume......, the thesis extends the application of remote sensing methods to estimate important variables with relevance to water catchment management....

  6. Regional differences in recipient waitlist time and pre- and post-transplant mortality after the 2006 United Network for Organ Sharing policy changes in the donor heart allocation algorithm.

    Science.gov (United States)

    Schulze, P Christian; Kitada, Shuichi; Clerkin, Kevin; Jin, Zhezhen; Mancini, Donna M

    2014-04-01

    This study examined the impact of the United Network for Organ Sharing (UNOS) policy changes for regional differences in waitlist time and mortality before and after heart transplantation. The 2006 UNOS thoracic organ allocation policy change was implemented to allow for greater regional sharing of organs for heart transplantation. We analyzed 36,789 patients who were listed for heart transplantation from January 1999 through April 2012. These patients were separated into 2 eras centered on the July 12, 2006 UNOS policy change. Pre- and post-transplantation characteristics were compared by UNOS regions. Waitlist mortality decreased nationally (up to 180 days: 13.3% vs. 7.9% after the UNOS policy change, p < 0.001) and within each region. Similarly, 2-year post-transplant mortality decreased nationally (2-year mortality: 17.3% vs. 14.6%; p < 0.001) as well as regionally. Waitlist time for UNOS status 1A and 1B candidates increased nationally 17.8 days on average (p < 0.001) with variability between the regions. The greatest increases were in Region 9 (59.2-day increase, p < 0.001) and Region 4 (41.2-day increase, p < 0.001). Although the use of mechanical circulatory support increased nearly 2.3-fold nationally in Era 2, significant differences were present on a regional basis. In Regions 6, 7, and 10, nearly 40% of those transplanted required left ventricular assist device bridging, whereas only 19.6%, 22.3%, and 15.5% required a left ventricular assist device in regions 3, 4, and 5, respectively. The 2006 UNOS policy change has resulted in significant regional heterogeneity with respect to waitlist time and reliance on mechanical circulatory support as a bridge to transplantation, although overall both waitlist mortality and post-transplant survival are improved. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  7. Collagenolytic Activity Is Associated with Scar Resolution in Zebrafish Hearts after Cryoinjury

    Science.gov (United States)

    Gamba, Laurent; Amin-Javaheri, Armaan; Kim, Jieun; Warburton, David; Lien, Ching-Ling

    2017-01-01

    Myocardial infarction is the major cause of cardiac injury in western countries and can result in a massive loss of heart cells, leading eventually to heart failure. A fibrotic collagen-rich scar may prevent ventricular wall rupture, but also may result in heart failure because of its stiffness. In zebrafish, cardiac cryoinjury triggers a fibrotic response and scarring. Unlike with mammals, zebrafish heart has the striking ability to regenerate and to resolve the scar. Thus, understanding the mechanisms of scar resolution in zebrafish heart might facilitate the design of new therapeutic approaches to improve the recovery of patients. To visualize the collagenolytic activity within the zebrafish heart following cryoinjury, we used an in situ collagen zymography assay. We detected expression of mmp2 and mmp14a and these matrix metalloproteinases might contribute to the collagenase activity. Collagenolytic activity was present in the wound area, but decreased as the myocardium regenerated. Comparison with neonatal mouse hearts that failed to regenerate after transmural cryoinjury revealed a similar collagenolytic activity in the scar. These findings suggest that collagenolytic activity may be key to how the zebrafish heart resolves its scar; however, it is not sufficient in mouse hearts that lack efficient myocardial regeneration. PMID:29367534

  8. Detection of cardiac wall motion defects with combined amplitude/phase analysis

    International Nuclear Information System (INIS)

    Bacharach, S.L.; Green, M.V.; Bonow, R.O.; Pace, L.; Brunetti, A.; Larson, S.M.

    1985-01-01

    Fourier phase images have been used with some success to detect and quantify left ventricular (LV) wall motion defects. In abnormal regions of the LV, wall motion asynchronies often cause the time activity curve (TAC) to be shifted in phase. Such regional shifts are detected by analysis of the distribution function of phase values over the LV. However, not all wall motion defects result in detectable regional phase abnormalities. Such abnormalities may cause a reduction in the magnitude of contraction (and hence TAC amplitude) without any appreciable change in TAC shape(and hence phase). In an attempt to improve the sensitivity of the Fourier phase method for the detection of wall motion defects the authors analyzed the distribution function of Fourier amplitude as well as phase. 26 individuals with normal cardiac function and no history of cardiac disease served as controls. The goal was to detect and quantify wall motion as compared to the consensus of 3 independent observers viewing the scintigraphic cines. 26 subjects with coronary artery disease and mild wall motion defects (22 with normal EF) were studied ate rest. They found that analysis of the skew of thew amplitude distribution function improved the sensitivity for the detection of wall motion abnormalities at rest in the group from 65% to 85% (17/26 detected by phase alone, 22/26 by combined phase and amplitude analysis) while retaining a 0 false positive rate in the normal group. The authors conclude that analysis of Fourier amplitude distribution functions can significantly increase the sensitivity of phase imaging for detection of wall motion abnormalities

  9. A New High-Resolution Spectral Approach to Noninvasively Evaluate Wall Deformations in Arteries

    Directory of Open Access Journals (Sweden)

    Ivonne Bazan

    2014-01-01

    Full Text Available By locally measuring changes on arterial wall thickness as a function of pressure, the related Young modulus can be evaluated. This physical magnitude has shown to be an important predictive factor for cardiovascular diseases. For evaluating those changes, imaging segmentation or time correlations of ultrasonic echoes, coming from wall interfaces, are usually employed. In this paper, an alternative low-cost technique is proposed to locally evaluate variations on arterial walls, which are dynamically measured with an improved high-resolution calculation of power spectral densities in echo-traces of the wall interfaces, by using a parametric autoregressive processing. Certain wall deformations are finely detected by evaluating the echoes overtones peaks with power spectral estimations that implement Burg and Yule Walker algorithms. Results of this spectral approach are compared with a classical cross-correlation operator, in a tube phantom and “in vitro” carotid tissue. A circulating loop, mimicking heart periods and blood pressure changes, is employed to dynamically inspect each sample with a broadband ultrasonic probe, acquiring multiple A-Scans which are windowed to isolate echo-traces packets coming from distinct walls. Then the new technique and cross-correlation operator are applied to evaluate changing parietal deformations from the detection of displacements registered on the wall faces under periodic regime.

  10. A New High-Resolution Spectral Approach to Noninvasively Evaluate Wall Deformations in Arteries

    Science.gov (United States)

    Bazan, Ivonne; Negreira, Carlos; Ramos, Antonio; Brum, Javier; Ramirez, Alfredo

    2014-01-01

    By locally measuring changes on arterial wall thickness as a function of pressure, the related Young modulus can be evaluated. This physical magnitude has shown to be an important predictive factor for cardiovascular diseases. For evaluating those changes, imaging segmentation or time correlations of ultrasonic echoes, coming from wall interfaces, are usually employed. In this paper, an alternative low-cost technique is proposed to locally evaluate variations on arterial walls, which are dynamically measured with an improved high-resolution calculation of power spectral densities in echo-traces of the wall interfaces, by using a parametric autoregressive processing. Certain wall deformations are finely detected by evaluating the echoes overtones peaks with power spectral estimations that implement Burg and Yule Walker algorithms. Results of this spectral approach are compared with a classical cross-correlation operator, in a tube phantom and “in vitro” carotid tissue. A circulating loop, mimicking heart periods and blood pressure changes, is employed to dynamically inspect each sample with a broadband ultrasonic probe, acquiring multiple A-Scans which are windowed to isolate echo-traces packets coming from distinct walls. Then the new technique and cross-correlation operator are applied to evaluate changing parietal deformations from the detection of displacements registered on the wall faces under periodic regime. PMID:24688596

  11. European Regional activation towards Brussels: From the heart to the Ultra-periphery of Europe. Walloon and Canary Islands’ strategies

    Directory of Open Access Journals (Sweden)

    Jorge Tuñón

    2008-06-01

    Full Text Available Wallonia and the Canary Islands are both regions with legislative capacities within the European Union (EU. They have traditionally shared serious socio-economic deficits. Therefore, while a new European Regional policy was being designed, they both built regional strategies in order to extract as much as they can from the EU. How far are these Sub-State activations towards Brussels linked to regional gains (outputs from the EU? How different are both mobilisations? How can the higher degree of success of the Canary Islands be explained, taking into account that the Archipelago is far away from the heart of Europe and Wallonia is within it? The research, based on a qualitative analysis method, will be carried out through findings about the regional mechanisms developed to influence the European institutions: the participation (direct and non direct within the Council of Ministers, the Committee of the Regions, the regional interaction with the European Commission, the establishment of representative bodies in Brussels and the participation within interregional associations.

  12. Reversible Stress Cardiomyopathy Presenting as Acute Coronary Syndrome with Elevated Troponin in the Absence of Regional Wall Motion Abnormalities: A Forme Fruste of Stress Cardiomyopathy?

    Directory of Open Access Journals (Sweden)

    Mahesh Anantha Narayanan

    2014-01-01

    Full Text Available We present a case of reversible stress cardiomyopathy in a surgical patient, described here as a forme fruste due to its atypical features. It is important to recognize such unusual presentation of stress cardiomyopathy that mimics acute coronary syndrome. Stress cardiomyopathy commonly presents as acute coronary syndrome and is characterized by typical or atypical variants of regional wall motion abnormalities. We report a 60-year-old Caucasian male with reversible stress cardiomyopathy following a sternal fracture fixation. Although the patient had several typical features of stress cardiomyopathy including physical stress, ST-segment elevation, elevated cardiac biomarkers and normal epicardial coronaries, there were few features that were atypical, including unusual age, gender, absence of regional wall motion abnormalities, high lateral ST elevation, and high troponin-ejection fraction product. In conclusion, this could represent a forme fruste of stress cardiomyopathy.

  13. Right ventricular function in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Araki, Haruo; Hisano, Ryuichi; Nagata, Yoshiyuki; Caglar, N.; Nakamura, Motoomi

    1985-01-01

    Thirty-five patients with ischemic heart disease (IHD) and 10 normal subjects were studied. Right and left ventricular ejecction fractions (EF) were determined using equilibrium radionuclide ventriculography with technetium-99m. Furthermore, abnormal motion of the right ventricular septal wall was obtained by cardiac cathetelization, and its relation to the right ventricular EF was examined. In IHD patients with anterior myocardial infarction, left ventricular EF decreased, but right ventricular EF was normal. This suggested that left ventricular dysfunction does not always have an effect on right ventricular function. Right ventricular EF was normal even when akinesis or dyskinesis was present in the ventricular septul, suggesting that abnormal motion of the ventricular septal wall has no significantly stimulant effect on right ventricular function. A decreased right ventricular EF was likely to occur only when the right ventricular free wall became ischemic or necrotic simultaneously with occurrence of posterior myocardial infarction. (Namekawa, K.)

  14. 4D blood flow mapping using SPIM-microPIV in the developing zebrafish heart

    Science.gov (United States)

    Zickus, Vytautas; Taylor, Jonathan M.

    2018-02-01

    Fluid-structure interaction in the developing heart is an active area of research in developmental biology. However, investigation of heart dynamics is mostly limited to computational uid dynamics simulations using heart wall structure information only, or single plane blood ow information - so there is a need for 3D + time resolved data to fully understand cardiac function. We present an imaging platform combining selective plane illumination microscopy (SPIM) with micro particle image velocimetry (μPIV) to enable 3D-resolved flow mapping in a microscopic environment, free from many of the sources of error and bias present in traditional epi uorescence-based μPIV systems. By using our new system in conjunction with optical heart beat synchronization, we demonstrate the ability obtain non-invasive 3D + time resolved blood flow measurements in the heart of a living zebrafish embryo.

  15. Investigating the Role of Interventricular Interdependence in Development of Right Heart Dysfunction During LVAD Support: A Patient-Specific Methods-Based Approach

    Directory of Open Access Journals (Sweden)

    Kevin L. Sack

    2018-05-01

    Full Text Available Predictive computation models offer the potential to uncover the mechanisms of treatments whose actions cannot be easily determined by experimental or imaging techniques. This is particularly relevant for investigating left ventricular mechanical assistance, a therapy for end-stage heart failure, which is increasingly used as more than just a bridge-to-transplant therapy. The high incidence of right ventricular failure following left ventricular assistance reflects an undesired consequence of treatment, which has been hypothesized to be related to the mechanical interdependence between the two ventricles. To investigate the implication of this interdependence specifically in the setting of left ventricular assistance device (LVAD support, we introduce a patient-specific finite-element model of dilated chronic heart failure. The model geometry and material parameters were calibrated using patient-specific clinical data, producing a mechanical surrogate of the failing in vivo heart that models its dynamic strain and stress throughout the cardiac cycle. The model of the heart was coupled to lumped-parameter circulatory systems to simulate realistic ventricular loading conditions. Finally, the impact of ventricular assistance was investigated by incorporating a pump with pressure-flow characteristics of an LVAD (HeartMate II™ operating between 8 and 12 k RPM in parallel to the left ventricle. This allowed us to investigate the mechanical impact of acute left ventricular assistance at multiple operating-speeds on right ventricular mechanics and septal wall motion. Our findings show that left ventricular assistance reduces myofiber stress in the left ventricle and, to a lesser extent, right ventricle free wall, while increasing leftward septal-shift with increased operating-speeds. These effects were achieved with secondary, potentially negative effects on the interventricular septum which showed that support from LVADs, introduces unnatural bending

  16. Role of nuclear medicine in ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Hayashida, Kohei; Nishimura, Tsunehiko; Uehara, Toshiisa; Naito, Hiroaki; Omine, Hiromi; Kozuka, Takahiro [National Cardiovascular Center, Suita, Osaka (Japan)

    1982-08-01

    With the progress in gamma camera and computer system, nuclear medicine has been applied for diagnostic tool in ischemic heart disease. There are two devices for cardiac images; (1) Radionuclide angiocardiography (RNA) by in vivo sup(99m)Tc-RBC labeling (2) Myocardial imaging by /sup 201/Tlcl. RNA can evaluate the kinesis of wall motion of left ventricle with gated pool scan and also detect reserve of cardiac function with exercise study. Myocardial imaging at rest can identify myocardial necrosis and the imaging in exercise can detect myocardial ischemia. The elaborateness and reproducibility of cardiac image in nuclear medicine will play the great role to evaluate clinical stage of ischemic heart disease by not only imaging but also functional diagnosis.

  17. Newer concepts in the pathophysiology of ischemic heart disease.

    Science.gov (United States)

    Kirk, E S; Factor, S; Sonnenblick, E H

    1984-11-01

    Thus the thrust of these studies suggests that blood flow is the overwhelming factor in determining the consequences of the imbalance of oxygen supply and demand. Moreover, the factors that determine the requirements for tissue survival in the presence of deep ischemia are not the same as those shown for the normal myocardium in figure 1. In deep ischemia, contraction ceases, and metabolism shifts from aerobic to anaerobic pathways. Survival rather than contractile function then becomes the agenda. Not only does supply tend to overshadow demand in determining extent of transmural necrosis, but the anatomical pattern of supply precisely delineates the region at risk following a coronary occlusion as well as the ultimate extent of infarction. These views are summarized in the model presented in figures 12 and 13. The anatomic distribution of the ligated artery determines the lateral limits of the ischemic region (Fig. 12) and thus the lateral extension of necrosis (Fig. 13). The extension of the necrosis across the heart wall depends largely on the status of perfusion within the ischemic region. Extension of an infarct, should it occur, has to be explained by other mechanisms. These might include: (i) vascular obstruction in adjacent vascular systems that were not involved in the first occlusion, (ii) relative ischemia in the normal tissue surrounding the ischemic tissue due to an increased wall stress at the demarcation between contracting and noncontracting tissue, or (9) interruption of vessels supplying large interdigitations of normal tissue within the originally ischemic tissue due to changes associated with the process of infarction of ischemia. Alternatively, much that is called extension of infarction may involve more of the wall transmurally without lateral extension. Additional features of the development of myocardial infarction in figures 12 and 13 include: (i) the development of collateral vessel function resulting in an increased capacity to supply the

  18. INTOR impurity control and first wall system

    International Nuclear Information System (INIS)

    Abdou, M.A.

    1983-04-01

    The highlights of the recent INTOR effort on examining the key issues of the impurity control/first wall system are summarized. The emphasis of the work was an integrated study of the edge-region physics, plasma-wall interaction, materials, engineering and magnetic considerations associated with the poloidal divertor and pump limiter. The development of limiter and divertor collector plate designs with an acceptable lifetime was a major part of the work

  19. [Present status and trend of heart fluid mechanics research based on medical image analysis].

    Science.gov (United States)

    Gan, Jianhong; Yin, Lixue; Xie, Shenghua; Li, Wenhua; Lu, Jing; Luo, Anguo

    2014-06-01

    With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV), speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.

  20. Gravitational lens effect of wall-like objects and its cosmological implications

    International Nuclear Information System (INIS)

    Tomita, Kenji.

    1990-08-01

    First we derive the gravitational deflection angle of light rays passing through a disk consisting of pressureless matter, and show that it behaves like a convex lens. Next we derive the two-ray difference of deflection angles by help of the Raychaudhuri equation, in the cases when the wall-like objects are dust walls and domain-walls. Moreover we derive the two-ray difference of deflection angles in a low mass-density regions lying between wall-like objects. This region plays a role of a concave lens, but it is shown that its effect is minor, compared with the effect of wall-like objects. On the basis of these deflection angle differences, we consider the gravitational lens effect of uniform wall-like objects which may exist homogeneously on the cosmological scale, and show that, in the case when the wall-like objects appear at the epoch of z = 5, the measured angles of the cosmic background radiation may be increased about 3-2 times owing to the integrated convex lens effect and so its measured anisotropy may be smaller by a factor of about 10-6 than the intrinsic one. (author)

  1. Pericardial and congestive heart failure diagnostic with CT-and MR-imaging

    International Nuclear Information System (INIS)

    Rienmueller, R.; Seiderer, M.; Doliva, R.; Kemkes, B.; Lissner, J.

    1986-01-01

    Angiocardiography is still considered the gold standard in the estimation of functional parameters of the heart. However because of the inferior density resolution and the draw back of superimposition of cardiac structures angiocardiography provides only limited information about non cardiac and some cardiac structures for instance: The perimyo-, endocardium, the valves, the myocardial perfusion and metabolism or coronary blood flow. The present diagnostic and prognostic validity of CT and MR in visualizing the pericardium, the left ventricular myocardium, the heart chambers and the great heart vessels in the clinical work up of patients with pericardial and congestive heart failure is demonstrated. MR is more reliable in the diagnosis of left ventricular myocardial atrophy or fibrosis than CT. Disadvantages of MR include the failure to identify endo-, myo-and pericardial calcifications. The measurable improvement in the visualization of systolic and diastolic myocardial wall thickness using MR is of marked prognostic value in the preoperative exclusion of myocardial atrophy or fibrosis in patients with pericardial constriction

  2. Failure Behavior of Elbows with Local Wall Thinning

    Science.gov (United States)

    Lee, Sung-Ho; Lee, Jeong-Keun; Park, Jai-Hak

    Wall thinning defect due to corrosion is one of major aging phenomena in carbon steel pipes in most plant industries, and it results in reducing load carrying capacity of the piping components. A failure test system was set up for real scale elbows containing various simulated wall thinning defects, and monotonic in-plane bending tests were performed under internal pressure to find out the failure behavior of them. The failure behavior of wall-thinned elbows was characterized by the circumferential angle of thinned region and the loading conditions to the piping system.

  3. The origin of 'Great Walls'

    International Nuclear Information System (INIS)

    Shandarin, Sergei F.

    2009-01-01

    A new semi-analytical model that explains the formation and sizes of the 'great walls' - the largest structures observed in the universe is suggested. Although the basis of the model is the Zel'dovich approximation it has been used in a new way very different from the previous studies. Instead of traditional approach that evaluates the nonlinear density field it has been utilized for identification of the regions in Lagrangian space that after the mapping to real or redshift space (depending on the kind of structure is studied) end up in the regions where shell-crossing occurs. The set of these regions in Lagrangian space form the progenitor of the structure and after the mapping it determines the pattern of the structure in real or redshift space. The particle trajectories have crossed in such regions and the mapping is no longer unique there. The progenitor after mapping makes only one stream in the multi-stream flow regions therefore it does not comprise all the mass. Nevertheless, it approximately retains the shape of the structure. The progenitor of the structure in real space is determined by the linear density field along with two non-Gaussian fields derived from the initial potential. Its shape in Eulerian space is also affected by the displacement field. The progenitor of the structure in redshift space also depends on these fields but in addition it is strongly affected by two anisotropic fields that determine the pattern of great walls as well as their huge sizes. All the fields used in the mappings are derived from the linear potential smoothed at the current scale of nonlinearity which is R nl = 2.7 h −1 Mpc for the adopted parameters of the ΛCDM universe normalized to σ 8 = 0.8. The model predicts the existence of walls with sizes significantly greater than 500 h −1 Mpc that may be found in sufficiently large redshift surveys

  4. Imaging regional metabolic changes in the ischemic rat heart in vivo using hyperpolarized(1-13C)Pyruvate

    DEFF Research Database (Denmark)

    Lauritzen, Mette Hauge; Magnusson, Peter; Laustsen, Christoffer

    2017-01-01

    in the in vivo rat heart in an open-chest model of ischemia reperfusion. Hyperpolarized MRI enables new possibilities for evaluating changes in cardiac metabolism noninvasively and in real time, which potentially could be used for research to evaluate new treatments and metabolic interventions for myocardial......We evaluated the use of hyperpolarized 13C magnetic resonance imaging (MRI) in an open-chest rat model of myocardial infarction to image regional changes in myocardial metabolism. In total, 10 rats were examined before and after 30 minutes of occlusion of the left anterior descending coronary...

  5. Remnant Cholesterol Elicits Arterial Wall Inflammation and a Multilevel Cellular Immune Response in Humans.

    Science.gov (United States)

    Bernelot Moens, Sophie J; Verweij, Simone L; Schnitzler, Johan G; Stiekema, Lotte C A; Bos, Merijn; Langsted, Anne; Kuijk, Carlijn; Bekkering, Siroon; Voermans, Carlijn; Verberne, Hein J; Nordestgaard, Børge G; Stroes, Erik S G; Kroon, Jeffrey

    2017-05-01

    Mendelian randomization studies revealed a causal role for remnant cholesterol in cardiovascular disease. Remnant particles accumulate in the arterial wall, potentially propagating local and systemic inflammation. We evaluated the impact of remnant cholesterol on arterial wall inflammation, circulating monocytes, and bone marrow in patients with familial dysbetalipoproteinemia (FD). Arterial wall inflammation and bone marrow activity were measured using 18 F-FDG PET/CT. Monocyte phenotype was assessed with flow cytometry. The correlation between remnant levels and hematopoietic activity was validated in the CGPS (Copenhagen General Population Study). We found a 1.2-fold increase of 18 F-FDG uptake in the arterial wall in patients with FD (n=17, age 60±8 years, remnant cholesterol: 3.26 [2.07-5.71]) compared with controls (n=17, age 61±8 years, remnant cholesterol 0.29 [0.27-0.40]; P wall and cellular inflammation. These findings imply an important inflammatory component to the atherogenicity of remnant cholesterol, contributing to the increased cardiovascular disease risk in patients with FD. © 2017 American Heart Association, Inc.

  6. Wall shear stress measurement of near-wall flow over inclined and curved boundaries by stereo interfacial particle image velocimetry

    International Nuclear Information System (INIS)

    Nguyen, Thien Duy; Wells, John Craig; Nguyen, Chuong Vinh

    2010-01-01

    In investigations of laminar or turbulent flows, wall shear is often important. Nevertheless, conventional particle image velocimetry (PIV) is difficult in near-wall regions. A near-wall measurement technique, named interfacial PIV (IPIV) [Nguyen, C., Nguyen, T., Wells, J., Nakayama, A., 2008. Proposals for PIV of near-wall flow over curved boundaries. In: Proceedings of 14th International Symposium on Applications of Laser Technique to Fluid Mechanics], handles curved boundaries by means of conformal transformation, directly measures the wall gradient, and yields the near-wall tangential velocity profile at one-pixel resolution. In this paper, we show the feasibility of extending IPIV to measure wall gradients by stereo reconstruction. First, we perform a test on synthetic images generated from a direct numerical simulation (DNS) snapshot of turbulent flow over sinusoidal bed. Comparative assessment of wall gradients derived by IPIV, stereo-IPIV and particle image distortion (PID) [Huang, H.T., Fiedler, H.E., Wang, J.J., 1993. Limitation and improvement of PIV. Experiments in Fluids 15(4), 263-273] is evaluated with DNS data. Also, the sensitivity of IPIV and stereo-IPIV results to the uncertainty of identified wall position is examined. As a practical application of IPIV and stereo-IPIV to experimental images, results from turbulent open channel flow over a backward-facing step are discussed in detail.

  7. Active inhibitor-1 maintains protein hyper-phosphorylation in aging hearts and halts remodeling in failing hearts.

    Science.gov (United States)

    Pritchard, Tracy J; Kawase, Yoshiaki; Haghighi, Kobra; Anjak, Ahmad; Cai, Wenfeng; Jiang, Min; Nicolaou, Persoulla; Pylar, George; Karakikes, Ioannis; Rapti, Kleopatra; Rubinstein, Jack; Hajjar, Roger J; Kranias, Evangelia G

    2013-01-01

    Impaired sarcoplasmic reticulum calcium cycling and depressed contractility are key characteristics in heart failure. Defects in sarcoplasmic reticulum function are characterized by decreased SERCA2a Ca-transport that is partially attributable to dephosphorylation of its regulator phospholamban by increased protein phosphatase 1 activity. Inhibition of protein phosphatase 1 through activation of its endogenous inhibitor-1 has been shown to enhance cardiac Ca-handling and contractility as well as protect from pathological stress remodeling in young mice. In this study, we assessed the long-term effects of inducible expression of constitutively active inhibitor-1 in the adult heart and followed function and remodeling through the aging process, up to 20 months. Mice with inhibitor-1 had normal survival and similar function to WTs. There was no overt remodeling as evidenced by measures of left ventricular end-systolic and diastolic diameters and posterior wall dimensions, heart weight to tibia length ratio, and histology. Higher phosphorylation of phospholamban at both Ser16 and Thr17 was maintained in aged hearts with active inhibitor-1, potentially offsetting the effects of elevated Ser2815-phosphorylation in ryanodine receptor, as there were no increases in arrhythmias under stress conditions in 20-month old mice. Furthermore, long-term expression of active inhibitor-1 via recombinant adeno-associated virus type 9 gene transfer in rats with pressure-overload induced heart failure improved function and prevented remodeling, associated with increased phosphorylation of phospholamban at Ser16 and Thr17. Thus, chronic inhibition of protein phosphatase 1, through increases in active inhibitor-1, does not accelerate age-related cardiomyopathy and gene transfer of this molecule in vivo improves function and halts remodeling in the long term.

  8. Limb-body wall defect: experience of a reference service of fetal medicine from Southern Brazil.

    Science.gov (United States)

    Gazolla, Ana C; da Cunha, André C; Telles, Jorge A B; Betat, Rosilene da S; Romano, Mayara A; Marshall, Isabel; Gobatto, Amanda M; de H Bicca, Anna M; Arcolini, Camila P; Dal Pai, Thaís K V; Vieira, Luciane R; Targa, Luciano V; Betineli, Ildo; Zen, Paulo R G; Rosa, Rafael F M

    2014-10-01

    Limb-body wall defect is a rare condition characterized by a combination of large and complex defects of the ventral thorax and abdominal wall with craniofacial and limb anomalies. The aim of this study was to describe the experience of our fetal medicine service, a reference from Southern Brazil, with prenatally diagnosed patients with a limb-body wall defect in a 3 years period. Only patients who fulfilled the criteria suggested by Hunter et al. (2011) were included in the study. Clinical data and results of radiological and cytogenetic evaluation were collected from their medical records. Our sample was composed of 8 patients. Many of their mothers were younger than 25 years (50%) and in their first pregnancy (62.5%). It is noteworthy that one patient was referred due to suspected anencephaly and another due to a twin pregnancy with an embryonic sac. Craniofacial defects were verified in three patients (37.5%), thoracic/abdominal abnormalities in 6 (75%) and limb defects in eight (100%). Congenital heart defects were observed in five patients (62.5%). One of them presented a previously undescribed complex heart defect. The results disclosed that complementary exams, such as MRI and echocardiography, are important to better define the observed defects. Some of them, such as congenital heart defects, may be more common than previously reported. This definition is essential for the proper management of the pregnancy and genetic counseling of the family. The birth of these children must be planned with caution and for the prognosis a long survival possibility, despite unlikely and rare, must be considered. © 2014 Wiley Periodicals, Inc.

  9. Two endogenous proteins that induce cell wall extension in plants

    Science.gov (United States)

    McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

    1992-01-01

    Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

  10. Technical Note: A 3-D rendering algorithm for electromechanical wave imaging of a beating heart.

    Science.gov (United States)

    Nauleau, Pierre; Melki, Lea; Wan, Elaine; Konofagou, Elisa

    2017-09-01

    Arrhythmias can be treated by ablating the heart tissue in the regions of abnormal contraction. The current clinical standard provides electroanatomic 3-D maps to visualize the electrical activation and locate the arrhythmogenic sources. However, the procedure is time-consuming and invasive. Electromechanical wave imaging is an ultrasound-based noninvasive technique that can provide 2-D maps of the electromechanical activation of the heart. In order to fully visualize the complex 3-D pattern of activation, several 2-D views are acquired and processed separately. They are then manually registered with a 3-D rendering software to generate a pseudo-3-D map. However, this last step is operator-dependent and time-consuming. This paper presents a method to generate a full 3-D map of the electromechanical activation using multiple 2-D images. Two canine models were considered to illustrate the method: one in normal sinus rhythm and one paced from the lateral region of the heart. Four standard echographic views of each canine heart were acquired. Electromechanical wave imaging was applied to generate four 2-D activation maps of the left ventricle. The radial positions and activation timings of the walls were automatically extracted from those maps. In each slice, from apex to base, these values were interpolated around the circumference to generate a full 3-D map. In both cases, a 3-D activation map and a cine-loop of the propagation of the electromechanical wave were automatically generated. The 3-D map showing the electromechanical activation timings overlaid on realistic anatomy assists with the visualization of the sources of earlier activation (which are potential arrhythmogenic sources). The earliest sources of activation corresponded to the expected ones: septum for the normal rhythm and lateral for the pacing case. The proposed technique provides, automatically, a 3-D electromechanical activation map with a realistic anatomy. This represents a step towards a

  11. Anterior chest wall examination reviewed

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Anterior chest wall involvement is not infrequently observed within inflammatory arthropaties, particularly if one considers seronegative spondiloarthritides and SAPHO syndrome. Physical examination is unreliable and conventional X-rays analysis is an unsatisfactory tool during diagnostic work-up of this region. Scintigraphic techniques yield informations both on the activity and on the anatomical extent of the disease while computerized tomography visualize the elementary lesions, such as erosions, which characterize the process. Moreover, when available, magnetic resonance imaging couple the ability to finely visualize such lesions with the possibility to show early alterations and to characterize the “activity” of the disease, presenting itself as a powerful tool both for diagnosis and follow-up. This review briefly shows the applications of imaging techniques for the evaluation of the anterior chest wall focusing on what has been done in the SAPHO syndrome which can be considered prototypical for this regional involvement since it is the osteo-articular target mainly affected by the disease.

  12. Examination of wall functions for a Parabolized Navier-Stokes code for supersonic flow

    Energy Technology Data Exchange (ETDEWEB)

    Alsbrooks, T.H. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Mechanical Engineering

    1993-04-01

    Solutions from a Parabolized Navier-Stokes (PNS) code with an algebraic turbulence model are compared with wall functions. The wall functions represent the turbulent flow profiles in the viscous sublayer, thus removing many grid points from the solution procedure. The wall functions are intended to replace the computed profiles between the body surface and a match point in the logarithmic region. A supersonic adiabatic flow case was examined first. This adiabatic case indicates close agreement between computed velocity profiles near the wall and the wall function for a limited range of suitable match points in the logarithmic region. In an attempt to improve marching stability, a laminar to turbulent transition routine was implemented at the start of the PNS code. Implementing the wall function with the transitional routine in the PNS code is expected to reduce computational time while maintaining good accuracy in computed skin friction.

  13. Examination of wall functions for a Parabolized Navier-Stokes code for supersonic flow

    Energy Technology Data Exchange (ETDEWEB)

    Alsbrooks, T.H. (New Mexico Univ., Albuquerque, NM (United States). Dept. of Mechanical Engineering)

    1993-01-01

    Solutions from a Parabolized Navier-Stokes (PNS) code with an algebraic turbulence model are compared with wall functions. The wall functions represent the turbulent flow profiles in the viscous sublayer, thus removing many grid points from the solution procedure. The wall functions are intended to replace the computed profiles between the body surface and a match point in the logarithmic region. A supersonic adiabatic flow case was examined first. This adiabatic case indicates close agreement between computed velocity profiles near the wall and the wall function for a limited range of suitable match points in the logarithmic region. In an attempt to improve marching stability, a laminar to turbulent transition routine was implemented at the start of the PNS code. Implementing the wall function with the transitional routine in the PNS code is expected to reduce computational time while maintaining good accuracy in computed skin friction.

  14. In situ stabilization wall for containment and hot spot retrieval

    International Nuclear Information System (INIS)

    Loomis, G.G.

    1996-01-01

    This paper presents the results of a full scale field demonstration of a in situ stabilization technology applicable to buried transuranic waste. The technology involves creating a jet grouted wall around selected regions or hot spots within a buried waste site. The resulting wall provides a barrier against further horizontal migration of the contaminants and allows vertical digging of material inside the wall, thus minimizing waste during a hot spot removal action. The demonstration involved creating a open-quotes Uclose quotes shaped wall in the interior of a full sized, simulated waste pit. The wall simulated the main features of a four sided wall. The demonstration also involved a destructive examination and a stability test for a hot spot retrieval scenario

  15. ENHANCEMENT OF A SUNSPOT LIGHT WALL WITH EXTERNAL DISTURBANCES

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shuhong; Zhang, Jun [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Erdélyi, Robert, E-mail: shuhongyang@nao.cas.cn [Solar Physics and Space Plasma Research Centre, School of Mathematics and Statistics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2016-12-20

    Based on the Interface Region Imaging Spectrograph observations, we study the response of a solar sunspot light wall to external disturbances. A flare occurrence near the light wall caused material to erupt from the lower solar atmosphere into the corona. Some material falls back to the solar surface and hits the light bridge (i.e., the base of the light wall), then sudden brightenings appear at the wall base followed by the rise of wall top, leading to an increase of the wall height. Once the brightness of the wall base fades, the height of the light wall begins to decrease. Five hours later, another nearby flare takes place, and a bright channel is formed that extends from the flare toward the light bridge. Although no obvious material flow along the bright channel is found, some ejected material is conjectured to reach the light bridge. Subsequently, the wall base brightens and the wall height begins to increase again. Once more, when the brightness of the wall base decays, the wall top fluctuates to lower heights. We suggest, based on the observed cases, that the interaction of falling material and ejected flare material with the light wall results in the brightenings of wall base and causes the height of the light wall to increase. Our results reveal that the light wall can be not only powered by the linkage of p -mode from below the photosphere, but may also be enhanced by external disturbances, such as falling material.

  16. H.Ea.R.T. 2013 Conference

    CERN Document Server

    Tampone, Gennaro; Zinno, Raffaele; Historical Earthquake-Resistant Timber Frames in the Mediterranean Area

    2015-01-01

    This book presents a selection of the best papers from the HEaRT 2013 conference, held in Cosenza, Italy, which provided a valuable forum for engineers and architects, researchers, and educators to exchange views and findings concerning the technological history, construction features, and seismic behavior of historical timber-framed walls in the Mediterranean countries. The topics covered are wide ranging and include historical aspects and examples of the use of timber-framed construction systems in response to earthquakes, such as the gaiola system in Portugal and the Bourbon system in southern Italy; interpretation of the response of timber-framed walls to seismic actions based on calculations and experimental tests; assessment of the effectiveness of repair and strengthening techniques, e.g., using aramid fiber wires or sheets; and modelling analyses. In addition, on the basis of case studies, a methodology is presented that is applicable to diagnosis, strengthening, and improvement of seismic performance...

  17. Direct myocardial perfusion imaging in valvular heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

    1981-02-01

    Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of /sup 99m/Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure.

  18. Direct myocardial perfusion imaging in valvular heart disease

    International Nuclear Information System (INIS)

    Soto, R.C.; Durante, M.L.; Villacorta, E.V.; Torres, J.F.; Monzon, O.P.

    1981-01-01

    Twenty two patients with rheumatic valvular heart disease - 21 having a history of heart failure - were studied using direct coronary injection of sup(99m)Tc labelled MAA particles during the course of hemodynamic and arteriographic studies. Myocardial perfusion deficit patterns have been shown to be consistent or indicative of either patchy, regional or gross ischemia. In patients with history of documented heart failure 90% (18 cases) had ischemic perfusion deficit in the involved ventricle. We conclude that diminished myocardial blood flow is an important mechanism contributing to the development of heart failure. (orig.) [de

  19. Heart valve cardiomyocytes of mouse embryos express the serotonin transporter SERT

    International Nuclear Information System (INIS)

    Pavone, Luigi Michele; Spina, Anna; Lo Muto, Roberta; Santoro, Dionea; Mastellone, Vincenzo; Avallone, Luigi

    2008-01-01

    Multiple evidence demonstrate a role for serotonin and its transporter SERT in heart valve development and disease. By utilizing a Cre/loxP system driven by SERT gene expression, we recently demonstrated a regionally restricted distribution of SERT-expressing cells in developing mouse heart. In order to characterize the cell types exhibiting SERT expression within the mouse heart valves at early developmental stages, in this study we performed immunohistochemistry for Islet1 (Isl1) and connexin-43 (Cx-43) on heart sections from SERT Cre/+ ;ROSA26R embryos previously stained with X-gal. We observed the co-localization of LacZ staining with Isl1 labelling in the outflow tract, the right ventricle and the conal region of E11.5 mouse heart. Cx-43 labelled cells co-localized with LacZ stained cells in the forming atrioventricular valves. These results demonstrate the cardiomyocyte phenotype of SERT-expressing cells in heart valves of the developing mouse heart, thus suggesting an active role of SERT in early heart valve development.

  20. Evaluation of regional pulmonary blood flow in mitral valvular heart disease using single-pass radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Chang-Soon Koh; Byung Tae Kim; Myung Chul Lee; Bo Yeon Cho

    1982-01-01

    Pulmonary hypertension in mitral valvular cardiac disease has been evaluated in 122 patients by a modified upper lung/lower count ratio using single-pass radionuclide angiocardiography. The mean upper lung/lower lung radio correlates well with pulmonary artery mean (r=0.483) and wedge pressure (r=0.804). After correction surgery of the cardiac valve, the ratio decreases and returns to normal range in patients judged clinically to have good surgical benifit. This modified method using single-pass technique provides additional simple, reproducible and nontraumatic results of regional pulmonary blood flow and appears to be correlated with the degree of pulmonary hypertension in mitral heart disease

  1. Clustering Of Left Ventricular Wall Motion Patterns

    Science.gov (United States)

    Bjelogrlic, Z.; Jakopin, J.; Gyergyek, L.

    1982-11-01

    A method for detection of wall regions with similar motion was presented. A model based on local direction information was used to measure the left ventricular wall motion from cineangiographic sequence. Three time functions were used to define segmental motion patterns: distance of a ventricular contour segment from the mean contour, the velocity of a segment and its acceleration. Motion patterns were clustered by the UPGMA algorithm and by an algorithm based on K-nearest neighboor classification rule.

  2. Relationship between the optimum cut off frequency for Butter worth filter and lung-heart ratio in 99mTc myocardial SPECT

    International Nuclear Information System (INIS)

    Salihin Yusoff, M. N.; Zakaria, A.

    2010-01-01

    We investigated whether the lung-heart ratio parameter can be used to identify the optimum cut off frequency for Butter worth filter in 99m Tc myocardial SPECT imaging. Materials and Methods: This study involved a cardiac phantom system consisting of cardiac insert in which 1.10 cm cold defect was inserted into its myocardium wall and filled with 4.0 μCi/ml (0.148 MBq/ml) 99m Tc concentration. The cardiac insert was then put into a cylindrical tank which filled with six different 99m Tc concentrations as background. Thus, six target background concentrations ratios (T/B) were carried out. The lung-heart ratio was determined for every SPECT raw image obtained corresponding to each T/B. Then, 130 different combinations of filter parameters from Butter worth filter were utilized to reconstruct each SPECT raw image. The determination of count in myocardium, background, and defect regions of interest were performed for every reconstructed image. All the count values were then used to calculate contrast, signal-to-noise ratio, and defect size. Each criterion was graded (1 to 100) and then summed together to obtain total grade. The optimum cut off frequency for each lung-heart ratio was determined from the total grade. The relation between optimum cut off frequency for Butter worth filter and lung-heart ratio was established using linear regression. Results: There were good relationship between the optimum Butter worth cut off frequency and lung-heart ratio (R 2 = 0.864, p<0.01). The optimal cut off frequency correspond to the change in lung-heart ratio can be expressed by the equation: Optimum cut off frequency=0.715*lung-heart ratio + 0.227. Conclusion: This study suggests that the optimum cut off frequency for Butter worth filter should be determined by referring to lung-heart ratio in each patient study.

  3. Partition wall structure in spent fuel storage pool and construction method for the partition wall

    International Nuclear Information System (INIS)

    Izawa, Masaaki

    1998-01-01

    A partitioning wall for forming cask pits as radiation shielding regions by partitioning inside of a spent fuel storage pool is prepared by covering both surface of a concrete body by shielding metal plates. The metal plate comprises opposed plate units integrated by welding while sandwiching a metal frame as a reinforcing material for the concrete body, the lower end of the units is connected to a floor of a pool by fastening members, and concrete is set while using the metal plate of the units as a frame to form the concrete body. The shielding metal plate has a double walled structure formed by welding a lining plate disposed on the outer surface of the partition wall and a shield plate disposed to the inner side. Then the term for construction can be shortened, and the capacity for storing spent fuels can be increased. (N.H.)

  4. Isolation of a novel cell wall architecture mutant of rice with defective Arabidopsis COBL4 ortholog BC1 required for regulated deposition of secondary cell wall components.

    Science.gov (United States)

    Sato, Kanna; Suzuki, Ryu; Nishikubo, Nobuyuki; Takenouchi, Sachi; Ito, Sachiko; Nakano, Yoshimi; Nakaba, Satoshi; Sano, Yuzou; Funada, Ryo; Kajita, Shinya; Kitano, Hidemi; Katayama, Yoshihiro

    2010-06-01

    The plant secondary cell wall is a highly ordered structure composed of various polysaccharides, phenolic components and proteins. Its coordinated regulation of a number of complex metabolic pathways and assembly has not been resolved. To understand the molecular mechanisms that regulate secondary cell wall synthesis, we isolated a novel rice mutant, cell wall architecture1 (cwa1), that exhibits an irregular thickening pattern in the secondary cell wall of sclerenchyma, as well as culm brittleness and reduced cellulose content in mature internodes. Light and transmission electron microscopy revealed that the cwa1 mutant plant has regions of local aggregation in the secondary cell walls of the cortical fibers in its internodes, showing uneven thickness. Ultraviolet microscopic observation indicated that localization of cell wall phenolic components was perturbed and that these components abundantly deposited at the aggregated cell wall regions in sclerenchyma. Therefore, regulation of deposition and assembly of secondary cell wall materials, i.e. phenolic components, appear to be disturbed by mutation of the cwa1 gene. Genetic analysis showed that cwa1 is allelic to brittle culm1 (bc1), which encodes the glycosylphosphatidylinositol-anchored COBRA-like protein specifically in plants. BC1 is known as a regulator that controls the culm mechanical strength and cellulose content in the secondary cell walls of sclerenchyma, but the precise function of BC1 has not been resolved. Our results suggest that CWA1/BC1 has an essential role in assembling cell wall constituents at their appropriate sites, thereby enabling synthesis of solid and flexible internodes in rice.

  5. Large-scale influences in near-wall turbulence.

    Science.gov (United States)

    Hutchins, Nicholas; Marusic, Ivan

    2007-03-15

    Hot-wire data acquired in a high Reynolds number facility are used to illustrate the need for adequate scale separation when considering the coherent structure in wall-bounded turbulence. It is found that a large-scale motion in the log region becomes increasingly comparable in energy to the near-wall cycle as the Reynolds number increases. Through decomposition of fluctuating velocity signals, it is shown that this large-scale motion has a distinct modulating influence on the small-scale energy (akin to amplitude modulation). Reassessment of DNS data, in light of these results, shows similar trends, with the rate and intensity of production due to the near-wall cycle subject to a modulating influence from the largest-scale motions.

  6. MR-evaluation of left myocardial function in transplanted hearts

    International Nuclear Information System (INIS)

    Rienmuller, R.K.; Lioret, J.; Kemkes, B.; Erdmann, E.; Gartner, C.; Hacker, H.; Tilling, R.

    1988-01-01

    Of 60 heart transplant recipients, 25 were restudied with magnetic resonance (MR) imaging after 1 year to evaluate the left ventricular myocardial (LVM) function, Seven healthy subjects and 15 patients with dilated cardiomyopathy (DCM) served as controls. EDV, ejection fraction (EF), LVMM, wall stress (T-diastolic, T-systolic), and LVM contraction and relaxation (LVMC, LVMR) were measured over a cardiac cycle and compared with angiocardiographic and clinical data. The results showed that EDV and EF were normal in heart transplant recipients both initially and at follow-up, and in healthy subjects. LVMM was significantly increased in patients with DCM and less so in transplant recipients. T-diastolic wall stress was increased in transplant recipients and patients with DCM. The isovolumetric part of LVMC and the LVMR were reduced in these groups, corresponding to restrictive hemodynamics. In transplant recipients at follow-up, a progressive reduction in LVMR was found. In transplant recipients with global myocardial ischemia, LVMM,LVMC,LVMR, and EF are continuously decreasing, in contrast to acute or subacute rejection, where LVMM was found unchanged or increased. In conclusion, LVMM, LVMR, and LVMC as determined by MR imaging are sensitive quantitative indexes of various causes of altered LVM function that result from (sub) acute, chronic rejection or graft atherosclerosis

  7. Studies on first wall and plasma wall interaction in JT-60

    International Nuclear Information System (INIS)

    Nakamura, Hiroo

    1988-12-01

    This paper describes studies on first wall and plasma wall interaction in JT-60. Main results are as follows; (1) To select JT-60 first wall material, various RandD were done in FY1975 ∼ 1976. Mo was selected as first wall materials of limiters and divertor plates because of its reliability under a high heat flux condition. (2) Development of low-Z material has been done to reduce impurity problem of Mo first wall. As a result, titanium carbide (TiC) was selected as a coating material on the Mo. High heat load testing has been done for TiC coated Mo limiter same as JT-60. This material can survive under the condition of 1 kW/cm 2 x 10 s, expected in JT-60 limiter design. (3) To reduce high heat load on the divertor plate, separatrix swing is proposed. Optimum frequency of the sweeping is evaluated to be 2 Hz in JT-60. For a discharge with heating power of 30 MW and duration time of 10 s, in addition to the separatrix swing, remote radiative cooling in the divertor region is necessary. Moreover, calculations of erosion thickness have been done for stainless steel, Mo, graphite, TiC and silicon caibide under high heat flux during plasma disruption. (4) In divertor experiments in JT-60, divertor functions on particle, heat load and impurity controls have been demonstrated. In elctron density of 6 x 10 19 m -3 , particle fueling rate of 20 MW NB heating (3 Pa m 3 /s) can be exhausted by divertor pumping system. Effectiveness of remote radiative cooling is demonstrated under the condition of 20 MW NB heating power. Also, separatrix swing is demonstrated to reduce heat load on the divertor plate. Total radiation in main plasma is 5 ∼ 10% of total absorbed power. (author) 120 refs

  8. Shear wall ultimate drift limits

    International Nuclear Information System (INIS)

    Duffey, T.A.; Goldman, A.; Farrar, C.R.

    1994-04-01

    Drift limits for reinforced-concrete shear walls are investigated by reviewing the open literature for appropriate experimental data. Drift values at ultimate are determined for walls with aspect ratios ranging up to a maximum of 3.53 and undergoing different types of lateral loading (cyclic static, monotonic static, and dynamic). Based on the geometry of actual nuclear power plant structures exclusive of containments and concerns regarding their response during seismic (i.e.,cyclic) loading, data are obtained from pertinent references for which the wall aspect ratio is less than or equal to approximately 1, and for which testing is cyclic in nature (typically displacement controlled). In particular, lateral deflections at ultimate load, and at points in the softening region beyond ultimate for which the load has dropped to 90, 80, 70, 60, and 50 percent of its ultimate value, are obtained and converted to drift information. The statistical nature of the data is also investigated. These data are shown to be lognormally distributed, and an analysis of variance is performed. The use of statistics to estimate Probability of Failure for a shear wall structure is illustrated

  9. Clinical use of nuclear cardiology in the assessment of heart failure

    International Nuclear Information System (INIS)

    Han Lei; Shi Hongcheng

    2011-01-01

    Nuclear cardiology is the most commonly performed non-invasive cardiac imaging test in patients with heart failure, and it plays an important role in their assessment and management. Quantitative gated single positron emission computed tomography is used to assess quantitatively cardiac volume, left ventricular ejection fraction, stroke volume, and cardiac diastolic function. Resting and stress myocardial perfusion imaging can not only identify nonischemic heart failure and ischemic heart failure, but also demonstrate myocardial viability. Diastolic heart failure also termed as heart failure with a preserved left ventricular ejection fraction is readily identified by nuclear cardiology techniques and can accurately be estimated by peak filling rate and time to peak filling rate. With newer techniques such as three-dimensional, quantitative gated single positron emission computed tomography can assess movement of the left ventricle, and wall thickening evaluation aids its assessment. Myocardial perfusion imaging is also commonly used to identify candidates for implantable cardiac defibrillator and cardiac resynchronization therapies. Neurotransmitter imaging using 123 I-metaiodobenzylguanidine offers prognostic information in patients with heart failure. Metabolism and function in the heart are closely related, and energy substrate metabolism is a potential target of medical therapies to improve cardiac function in patients with heart failure. Cardiac metabolic imaging using 123 I-15-(p-iodophenyl) 3-R, S-methylpentadecacoic acid is a commonly used tracer in clinical studies to diagnose metabolic heart failure. Nuclear cardiology tests, including neurotransmitter imaging and metabolic imaging, are now easily preformed with new tracers to improve heart failure diagnosis. Nuclear cardiology techniques contribute significantly to identifying patients with heart failure and to guiding their management decisions. (authors)

  10. The value of regional wall motion abnormalities on 99Tcm-MIBI gated cardiac SPECT in predicting angiographic stenoses of coronary artery

    International Nuclear Information System (INIS)

    Li Dianfu; Huang Jun; Zhu Tiebing; Wang Liansheng; Yang Zhijian; Feng Jianlin; Li Jianhua; Chen Jianwei; Chang Guojun

    2004-01-01

    Objective: To determine the magnitude of angiographic stenoses of coronary artery in reversible regional wall motion abnormalities (RWMA) present in exercise stress 99 Tc m -methoxyisobutylisonitrile (MIBI) gated SPECT myocardial perfusion imaging (MPI). Methods: One hundred and sixteen patients undergoing coronary angiography two weeks before and after the exercise stress 99 Tc m -MIBI gated SPECT MPI. Images were acquired 15 to 20 min after stress. A five grades and twenty segments marking system was introduced to assess the RWMA and thickening of left ventricles. Results: The sensitivity of reversible RWMA for detecting ≥75% angiographic stenoses was 65%, with a specificity of 97%. Reversible RWMA has a high positive predictive value (98%) for stratification between severe angiographic stenoses of 75% and non-severe stenoses (less than 75%). Multivariate analysis showed that the post-stress wall motion (SSSWM), exercise wall motion differentiation value (SDSWM) and summed stress score (SSS) were the independent risk factor of coronary artery jeopardy score. Conclusions: Reversible RWMA, as shown by exercise stress 99 Tc m -MIBI gated SPECT MPI, is a significant predictor of angiographic disease with very high specificity and positive predictive values. Exercise reversible RWMA can rise the assessment value of angiographic severity in MPI

  11. Inviscid Wall-Modeled Large Eddy Simulations for Improved Efficiency

    Science.gov (United States)

    Aikens, Kurt; Craft, Kyle; Redman, Andrew

    2015-11-01

    The accuracy of an inviscid flow assumption for wall-modeled large eddy simulations (LES) is examined because of its ability to reduce simulation costs. This assumption is not generally applicable for wall-bounded flows due to the high velocity gradients found near walls. In wall-modeled LES, however, neither the viscous near-wall region or the viscous length scales in the outer flow are resolved. Therefore, the viscous terms in the Navier-Stokes equations have little impact on the resolved flowfield. Zero pressure gradient flat plate boundary layer results are presented for both viscous and inviscid simulations using a wall model developed previously. The results are very similar and compare favorably to those from another wall model methodology and experimental data. Furthermore, the inviscid assumption reduces simulation costs by about 25% and 39% for supersonic and subsonic flows, respectively. Future research directions are discussed as are preliminary efforts to extend the wall model to include the effects of unresolved wall roughness. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1053575. Computational resources on TACC Stampede were provided under XSEDE allocation ENG150001.

  12. A SOLAR FLARE DISTURBING A LIGHT WALL ABOVE A SUNSPOT LIGHT BRIDGE

    International Nuclear Information System (INIS)

    Hou, Yijun; Zhang, Jun; Li, Ting; Yang, Shuhong; Li, Leping; Li, Xiaohong

    2016-01-01

    With the high-resolution data from the Interface Region Imaging Spectrograph , we detect a light wall above a sunspot light bridge in the NOAA active region (AR) 12403. In the 1330 Å slit-jaw images, the light wall is brighter than the ambient areas while the wall top and base are much brighter than the wall body, and it keeps oscillating above the light bridge. A C8.0 flare caused by a filament activation occurred in this AR with the peak at 02:52 UT on 2015 August 28, and the flare’s one ribbon overlapped the light bridge, which was the observational base of the light wall. Consequently, the oscillation of the light wall was evidently disturbed. The mean projective oscillation amplitude of the light wall increased from 0.5 to 1.6 Mm before the flare and decreased to 0.6 Mm after the flare. We suggest that the light wall shares a group of magnetic field lines with the flare loops, which undergo a magnetic reconnection process, and they constitute a coupled system. When the magnetic field lines are pushed upward at the pre-flare stage, the light wall turns to the vertical direction, resulting in the increase of the light wall’s projective oscillation amplitude. After the magnetic reconnection takes place, a group of new field lines with smaller scales are formed underneath the reconnection site, and the light wall inclines. Thus, the projective amplitude notably decrease at the post-flare stage.

  13. A SOLAR FLARE DISTURBING A LIGHT WALL ABOVE A SUNSPOT LIGHT BRIDGE

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Yijun; Zhang, Jun; Li, Ting; Yang, Shuhong; Li, Leping; Li, Xiaohong, E-mail: yijunhou@nao.cas.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2016-10-01

    With the high-resolution data from the Interface Region Imaging Spectrograph , we detect a light wall above a sunspot light bridge in the NOAA active region (AR) 12403. In the 1330 Å slit-jaw images, the light wall is brighter than the ambient areas while the wall top and base are much brighter than the wall body, and it keeps oscillating above the light bridge. A C8.0 flare caused by a filament activation occurred in this AR with the peak at 02:52 UT on 2015 August 28, and the flare’s one ribbon overlapped the light bridge, which was the observational base of the light wall. Consequently, the oscillation of the light wall was evidently disturbed. The mean projective oscillation amplitude of the light wall increased from 0.5 to 1.6 Mm before the flare and decreased to 0.6 Mm after the flare. We suggest that the light wall shares a group of magnetic field lines with the flare loops, which undergo a magnetic reconnection process, and they constitute a coupled system. When the magnetic field lines are pushed upward at the pre-flare stage, the light wall turns to the vertical direction, resulting in the increase of the light wall’s projective oscillation amplitude. After the magnetic reconnection takes place, a group of new field lines with smaller scales are formed underneath the reconnection site, and the light wall inclines. Thus, the projective amplitude notably decrease at the post-flare stage.

  14. Far- and near-field second-harmonic imaging of ferroelectric domain walls

    DEFF Research Database (Denmark)

    Bozhevolnyi, Sergey I.; Pedersen, K.; Skettrup, Torben

    1998-01-01

    Domain walls in periodically poled ferroelectric LiNbO3 crystals are observed with both far- and near-field imaging techniques that make use of second harmonic generation in the transition regions between neighbouring domains. Second harmonic images of domain walls represent bright lines of about.......5 micrometers in width (as measured with the near-field microscope) for the polarization of the second harmonic radiation perpendicular to the domain walls. Origin and selection rules for the constrast in second harmonic images of domain walls are discussed....

  15. OSCILLATING LIGHT WALL ABOVE A SUNSPOT LIGHT BRIDGE

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shuhong; Zhang, Jun; Jiang, Fayu [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Xiang, Yongyuan, E-mail: shuhongyang@nao.cas.cn [Fuxian Solar Observatory, Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

    2015-05-10

    With the high tempo-spatial Interface Region Imaging Spectrograph 1330 Å images, we find that many bright structures are rooted in the light bridge of NOAA 12192, forming a light wall. The light wall is brighter than the surrounding areas, and the wall top is much brighter than the wall body. The New Vacuum Solar Telescope Hα and the Solar Dynamics Observatory 171 and 131 Å images are also used to study the light-wall properties. In 1330, 171, and 131 Å, the top of the wall has a higher emission, while in the Hα line, the wall-top emission is very low. The wall body corresponds to bright areas in 1330 Å and dark areas in the other lines. The top of the light wall moves upward and downward successively, performing oscillations in height. The deprojected mean height, amplitude, oscillation velocity, and the dominant period are determined to be 3.6 Mm, 0.9 Mm, 15.4 km s{sup −1}, and 3.9 minutes, respectively. We interpret the oscillations of the light wall as the leakage of p-modes from below the photosphere. The constant brightness enhancement of the wall top implies the existence of some kind of atmospheric heating, e.g., via the persistent small-scale reconnection or the magneto-acoustic waves. In another series of 1330 Å images, we find that the wall top in the upward motion phase is significantly brighter than in the downward phase. This kind of oscillation may be powered by the energy released due to intermittent impulsive magnetic reconnection.

  16. Vortex ring behavior provides the epigenetic blueprint for the human heart.

    Science.gov (United States)

    Arvidsson, Per M; Kovács, Sándor J; Töger, Johannes; Borgquist, Rasmus; Heiberg, Einar; Carlsson, Marcus; Arheden, Håkan

    2016-02-26

    The laws of fluid dynamics govern vortex ring formation and precede cardiac development by billions of years, suggesting that diastolic vortex ring formation is instrumental in defining the shape of the heart. Using novel and validated magnetic resonance imaging measurements, we show that the healthy left ventricle moves in tandem with the expanding vortex ring, indicating that cardiac form and function is epigenetically optimized to accommodate vortex ring formation for volume pumping. Healthy hearts demonstrate a strong coupling between vortex and cardiac volumes (R(2) = 0.83), but this optimized phenotype is lost in heart failure, suggesting restoration of normal vortex ring dynamics as a new, and possibly important consideration for individualized heart failure treatment. Vortex ring volume was unrelated to early rapid filling (E-wave) velocity in patients and controls. Characteristics of vortex-wall interaction provide unique physiologic and mechanistic information about cardiac diastolic function that may be applied to guide the design and implantation of prosthetic valves, and have potential clinical utility as therapeutic targets for tailored medicine or measures of cardiac health.

  17. Flux measurements with a sniffer probe near the wall in ASDEX

    International Nuclear Information System (INIS)

    Poschenrieder, W.; Venus, G.; Wang, Y.G.; Mueller, E.R.; Bartiromo, R.; Becker, G.; Bosch, H.S.; Brocken, H.; Eberhagen, A.; Fussmann, G.; Gehre, O.; Gernhardt, J.; Gierke, G. v.; Glock, E.; Gruber, O.; Haas, G.; Janeschitz, G.; Karger, F.; Kotze, P.B.; Keilhacker, M.; Klueber, O.; Kornherr, M.; Lackner, K.; Lenoci, M.; Lisitano, G.; Mayer, H.M.; McCormick, K.; Meisel, D.; Mertens, V.; Murmann, H.; Niedermeyer, H.; Rapp, H.; Roehr, H.; Ryter, F.; Schneider, F.; Siller, G.; Smeulders, P.; Soeldner, F.; Speth, E.; Steuer, K.H.; Vollmer, O.; Wagner, F.

    1985-01-01

    For a detailed assessment of particle recycling in a tokamak it is necessary to know quality and quantity of the particle fluxes directed to the elements of the wall. In a divertor machine like ASDEX we have to differentiate between at least four distinct elements: main chamber wall, protective limiters, collector plates, and divertor walls. Relevant data about the divertor region are obtained from pressure and flux measurements. (orig./GG)

  18. EFFECT OF MITRAL REGURGITATION ON CHRONIC HEART FAILURE COURSE AND STRUCTURE-FUNCTIONAL HEART STATE

    Directory of Open Access Journals (Sweden)

    V. N. Larina

    2009-01-01

    Full Text Available Aim. To evaluate chronic heart failure (CHF course, functional and structural heart changes in patients with functional mitral regurgitation (MR of various degrees.Material and methods. A total of 104 outpatients (60-85 y. o. with CHF of functional class II-IV by NYHA and functional MR of I-II degrees and MR of III-IV degrees were included into the study groups.Results: Patients in both groups were comparable in sex, age, CHF duration, body mass index, systolic and diastolic blood pressure, clinical state by the clinical state scale, quality of life, anxious and depressive status. The majority of patients with MR III had significant left ventricle (LV systolic dysfunction (p=0,029, severe CHF course (p=0,034, received furosemide (p=0.004 and digoxin (p=0,004. They had significant increase in end-diastolic dimension (p<0,001, end-systolic dimension (p<0,001, left atrium (p=0,004, end-diastolic volume (p<0,001, end-systolic volume (p<0,001, pulmonary artery pressure (p<0,001, decrease in LV relative wall thickness (p=0,021 and LV ejection fraction (p<0,001. Patients of this group were hospitalized because of CHF decompensation and ischemic heart disease exacerbation more often (p=0,045.Conclusion. MR can be considered as one of sensitive predictors of LV geometry and function alteration in CHF patients and play an important role in symptoms development.

  19. EFFECT OF MITRAL REGURGITATION ON CHRONIC HEART FAILURE COURSE AND STRUCTURE-FUNCTIONAL HEART STATE

    Directory of Open Access Journals (Sweden)

    V. N. Larina

    2016-01-01

    Full Text Available Aim. To evaluate chronic heart failure (CHF course, functional and structural heart changes in patients with functional mitral regurgitation (MR of various degrees.Material and methods. A total of 104 outpatients (60-85 y. o. with CHF of functional class II-IV by NYHA and functional MR of I-II degrees and MR of III-IV degrees were included into the study groups.Results: Patients in both groups were comparable in sex, age, CHF duration, body mass index, systolic and diastolic blood pressure, clinical state by the clinical state scale, quality of life, anxious and depressive status. The majority of patients with MR III had significant left ventricle (LV systolic dysfunction (p=0,029, severe CHF course (p=0,034, received furosemide (p=0.004 and digoxin (p=0,004. They had significant increase in end-diastolic dimension (p<0,001, end-systolic dimension (p<0,001, left atrium (p=0,004, end-diastolic volume (p<0,001, end-systolic volume (p<0,001, pulmonary artery pressure (p<0,001, decrease in LV relative wall thickness (p=0,021 and LV ejection fraction (p<0,001. Patients of this group were hospitalized because of CHF decompensation and ischemic heart disease exacerbation more often (p=0,045.Conclusion. MR can be considered as one of sensitive predictors of LV geometry and function alteration in CHF patients and play an important role in symptoms development.

  20. Dynamics of plane-symmetric thin walls in general relativity

    International Nuclear Information System (INIS)

    Wang, A.

    1992-01-01

    Plane walls (including plane domain walls) without reflection symmetry are studied in the framework of Einstein's general relativity. Using the distribution theory, all the Einstein field equations and Bianchi identities are split into two groups: one holding in the regions outside of the wall and the other holding at the wall. The Einstein field equations at the wall are found to take a very simple form, and given explicitly in terms of the discontinuities of the metric coefficients and their derivatives. The Bianchi identities at the wall are also given explicitly. Using the latter, the interaction of a plane wall with gravitational waves and some specific matter fields is studied. In particular, it is found that, when a gravitational plane wave passes through a wall, if the wall has no reflection symmetry, the phenomena, such as reflection, stimulation, or absorption, in general, occur. It is also found that, unlike for gravitational waves, a massless scalar wave or an electromagnetic wave continuously passes through a wall without any reflection. The repulsion and attraction of a plane wall are also studied. It is found that the acceleration of an observer who is at rest relative to the wall usually consists of three parts: one is due to the force produced by the wall, the second is due to the force produced by the space-time curvature, which is zero if the wall has reflection symmetry, and the last is due to the accelerated motion of the wall. As a result, a repulsive (attractive) plane wall may not be repulsive (attractive) at all. Finally, the collision and interaction among the walls are studied

  1. Flow characteristics and scaling past highly porous wall-mounted fences

    Science.gov (United States)

    Rodríguez-López, Eduardo; Bruce, Paul J. K.; Buxton, Oliver R. H.

    2017-07-01

    An extensive characterization of the flow past wall-mounted highly porous fences based on single- and multi-scale geometries has been performed using hot-wire anemometry in a low-speed wind tunnel. Whilst drag properties (estimated from the time-averaged momentum equation) seem to be mostly dependent on the grids' blockage ratio; wakes of different size and orientation bars seem to generate distinct behaviours regarding turbulence properties. Far from the near-grid region, the flow is dominated by the presence of two well-differentiated layers: one close to the wall dominated by the near-wall behaviour and another one corresponding to the grid's wake and shear layer, originating from between this and the freestream. It is proposed that the effective thickness of the wall layer can be inferred from the wall-normal profile of root-mean-square streamwise velocity or, alternatively, from the wall-normal profile of streamwise velocity correlation. Using these definitions of wall-layer thickness enables us to collapse different trends of the turbulence behaviour inside this layer. In particular, the root-mean-square level of the wall shear stress fluctuations, longitudinal integral length scale, and spanwise turbulent structure is shown to display a satisfactory scaling with this thickness rather than with the whole thickness of the grid's wake. Moreover, it is shown that certain grids destroy the spanwise arrangement of large turbulence structures in the logarithmic region, which are then re-formed after a particular streamwise extent. It is finally shown that for fences subject to a boundary layer of thickness comparable to their height, the effective thickness of the wall layer scales with the incoming boundary layer thickness. Analogously, it is hypothesized that the growth rate of the internal layer is also partly dependent on the incoming boundary layer thickness.

  2. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    International Nuclear Information System (INIS)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun; Lee, Hyong Woo; Chung, Jin Hong

    1990-01-01

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  3. Identification and Assessment of Paradoxical Ventricular Wall Motion Using ECG Gated Blood Pool Scan - Comparison of cine Loop , Phase Analysis and Paradox Image -

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Tae; Kim, Gwang Weon; Lee, Kyu Bo; Chung, Byung Chun; Whang, Kee Suk; Chae, Sung Chul; Paek, Wee Hyun; Cheon, Jae Eun [Kyungpook National University School of Medicine, Daegu (Korea, Republic of); Lee, Hyong Woo; Chung, Jin Hong [Yeongnam National University College of Medicine, Daegu (Korea, Republic of)

    1990-07-15

    Sixty-four patients with paradoxical ventricular wall motion noticed both in angiocardiography or 2-dimensional echocardiography were assessed by ECG gated blood pool scan (GBPS). Endless cine loop image, phase and amplitude images and paradox image obtained by visual inspection of each cardiac beat or Fourier transformation of acquired raw data were investigated to determine the incremental value of GBPS with these processing methods for identification of paradoxical ventricular wall motion. The results were as follows:1) Paradoxical wall motions were observed on interventricular septum in 34 cases, left ventricular free wall in 26 and right ventricular wall in 24. Underlying heart diseases were is chemic (23 cases) valvular(9), congenital heart disease (12), cardiomyopathy (5), pericardial effusion(5), post cardiac surgery(3), corpulmonale (2), endocarditis (l) and right ventricular tumor(l). 2) Left ventricular ejection fractions of patients with paradoxical left ventricular wall motion were significantly lower than those with paradoxical septal motion (p <0.005). 3) The sensitivity of each processing methods for detecting paradoxical wall motion was 76.9% by phase analysis, 74.6% by endless cine loop mapping and 68.4% by paradox image manipulation respectively. Paradoxial motions visualized only in phase, paradox or both images were appeared as hypokinesia or akinesia in cine loop image. 4) All events could be identified by at least one of above three processing methods, however only 34 cases (48.4%) showed the paradoxical motions in all of the three images. By these findings, we concluded that simultaneous inspection of all above three processing methods-endless cine loop, phase analysis and paradox image is necessary for accurate identification and assessment of paradoxical ventricular wall motion when performing GBPS.

  4. Ancient engineering geology projects in China; A canal system in Ganzu province and trenches along the Great Wall in Ningxia Hui Autonomous Region

    Science.gov (United States)

    Wallace, R.E.; Bucknam, R.C.; Hanks, T.C.

    1994-01-01

    Two major construction projects of ancient times in China involved what today would be considered engineering geology. We describe an ancient canal system in Gaotai County, Gansu province that was possibly begun in the Han dynasty (206 BC-220 AD). The canal system heads at the Dasha River and extends northwestward for about 55 km to the City of Camels and Xusanwan village. Four parallel canals are present at the local site we examined. The canals were likely built primarily to transport water but may also have served as defensive military barriers. A second project involves trenches and berms along the north side of the Great Wall, clearly part of the Great Wall defensive system. This site is in Ningxia Autonomous Region near the town of Shizuishan. ?? 1994.

  5. Valvular Heart Disease in Heart Failure

    Directory of Open Access Journals (Sweden)

    Giuseppe MC Rosano

    2017-01-01

    Full Text Available Structural valvular heart disease may be the cause of heart failure or may worsen the clinical status of patients with heart failure. Heart failure may also develop in patients treated with valve surgery. Patients with heart failure with valvular heart disease are at increased risk of events including sudden cardiac death. Before considering intervention (surgical or percutaneous all patients should receive appropriate medical and device therapy taking into account that vasodilators must be used with caution in patients with severe aortic stenosis. Numerous percutaneous and/or hybrid procedures have been introduced in the past few years and they are changing the management of valvular heart disease. In patients with heart failure and valvular heart disease, either primary or functional, the whole process of decision-making should be staged through a comprehensive evaluation of the risk– benefit ratio of different treatment strategies and should be made by a multidisciplinary ‘heart team’ with a particular expertise in valvular heart disease. The heart team should include heart failure cardiologists, cardiac surgeons/structural valve interventionists, imaging specialists, anaesthetists, geriatricians and intensive care specialists. This article will review recent developments and distill practical guidance in the management of this important heart failure co-morbidity.

  6. Evaluation of wall thinning profile by flow accelerated corrosion in separation and union pipe

    International Nuclear Information System (INIS)

    Watanabe, Shun; Yoneda, Kimitoshi

    2013-01-01

    Flow Accelerated Corrosion (FAC) is a pipe wall thinning phenomena to be monitored and managed in power plants with high priority. At present, its management has been conducted with conservative evaluation of thinning rate and residual lifetime of the piping based on wall thickness measurements. However, noticeable case of wall thinning was occurred at separation and union pipe. In such pipe system, it is a problem to manage section beneath reinforcing plate of T-tube pipe and 'crotch' of T-joint pipe; the region where wall thickness measurement is difficult to conduct with ordinary ultrasonic testing device. In this study, numerical analysis for separation and union part of T-tube and T-joint pipe was conducted, and wall thinning profile by Flow Accelerated Corrosion was evaluated by calculating mass transfer coefficient and geometry factor. Based on these results, we considered applicable wall thinning management for T-tube and T-joint pipe. In the case of union flow from main and branch pipe, the wall thinning profile of T-tube showed the tendency of increase at main pipe like semielliptical region. On the other hand, noticeable profile appeared at 'crotch' in T-joint. Although it was found that geometry factor of T-joint in this case was half the value of T-tube, an alternative evaluation method to previous one might be needed for the profiles of 'semielliptical region' and 'crotch'. (author)

  7. Near-Wall Turbulence Modelling of Rotating and Curved Shear Flows

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Bjoern Anders

    1997-12-31

    This thesis deals with verification and refinement of turbulence models within the framework of the Reynolds-averaged approach. It pays special attention to modelling the near-wall region, where the turbulence is strongly non-homogeneous and anisotropic. It also studies in detail the effects associated with an imposed rotation of the reference frame or streamline curvature. The objective with near-wall turbulence closure modelling is to formulate a set of equations governing single point turbulence statistics, which can be solved in the region of the flow which extends to the wall. This is in contrast to the commonly adopted wall-function approach in which the wall-boundary conditions are replaced by matching conditions in the logarithmic region. The near-wall models allow more flexibility by not requiring any such universal behaviour. Assessment of the novel elliptic relaxation approach to model the proximity of a solid boundary reveals an encouraging potential used in conjunction with second-moment and eddy-viscosity closures. The most natural level of closure modelling to predict flows affected by streamline curvatures or an imposed rotation of the reference frame is at the second-moment closure (SMC) level. Although SMCs naturally accounts for the effects of system rotation, the usual application of a scalar dissipation rate equation is shown to require ad hoc corrections in some cases in order to give good results. The elliptic relaxation approach is also used in conjunction with non-linear pressure-strain models and very encouraging results are obtained for rotating flows. Rotational induced secondary motions are vital to predicting the effects of system rotation. Some severe weaknesses of non-linear pressure-strain models are also indicated. Finally, a modelling methodology for anisotropic dissipation in nearly homogeneous turbulence are proposed. 84 refs., 56 figs., 16 tabs.

  8. Irradiation of the chest wall and regional nodes as an integrated volume with IMRT for breast cancer after mastectomy: from dosimetry to clinical side-effects

    International Nuclear Information System (INIS)

    Ma Jinli; Li Jiongxiong; Zhu Chuanying

    2012-01-01

    Objective: To discuss dosimetric characteristics of an intensity-modulated radiotherapy (IMRT) technique for treating the chest wall and regional nodes as an integrated volume after modified radical mastectomy (MRM), and observe acute side-effects following irradiation. Methods: From June 2009 to August 2010, 75 patients were randomly enrolled. Of these, 41 had left-sided breast cancer. Each eligible patient had a planning CT in treatment position, on which the chest wall, supraclavicular,and infraclavicular nodes, +/-internal mammary region, were contoured as an integrated volume. A multi-beam IMRT plan was designed with the target either as a whole or two segments divided at below the clavicle head. A dose of 50 Gy in 25 fractions was prescribed to cover at least 90% of the PTV. Internal mammary region was included in 31 cases. Dose volume histograms were used to evaluate the IMRT plans. The acute side effects were followed up regularly during and after irradiation. The independent two-sample t-test was used to compare the dosimetric parameters between integrated and segmented plans. Results: Planning design was completed for all patients, including 55 integrated and 20 segmented plans, with median number of beams of 8. The conformity index and homogeneity index was 1.43 ± 0.15 and 0.14 ± 0.02, respectively. Patients with internal mammary region included in PTV had higher homogeneity index PT. The percent volume of PTV receiving > 110% prescription dose was max , D mean V 107% , and V 110% , between integrated and segmented plans (t=2.19 -2.53, P=0.013-0.031). ≥ grade 2 radiation dermatitis was identified in 3 2 patients (grade 2 in 22 patients, grade 3 in 10 patients), mostly occurred within 1 - 2 weeks after treatment. The sites of moist desquamation were anterior axillary fold (27/37) and chest wall (10/37). Only 2 patients developed grade 2 radiation pneumonitis. Conclusions: The IMRT technique applied after MRM with integrated locoregional target volume

  9. Thermal effect on heart rate and hemodynamics in vitelline arteries of stage 18 chicken embryos.

    Science.gov (United States)

    Lee, Jung Yeop; Lee, Sang Joon

    2010-12-01

    We investigated the thermal effects on heart rate, hemodynamics, and response of vitelline arteries of stage-18 chicken embryos. Heart rate was monitored by a high-speed imaging method, while hemodynamic quantities were evaluated using a particle image velocimetry (PIV) technique. Experiments were carried out at seven different temperatures (36-42 °C with 1 °C interval) after 1h of incubation to stabilize the heart rate. The heart rate increased in a linear manner (r = 0.992). Due to the increased cardiac output (or heart rate), the hemodynamic quantities such as mean velocity (U(mean)), velocity fluctuation (U(fluc)), and peak velocity (U(peak)) also increased with respect to the Womersley number (Ω) in the manner r = 0.599, 0.693, and 0.725, respectively. This indicates that the mechanical force exerting on the vessel walls increases. However, the active response (or regulation) of the vitelline arteries was not observed in this study. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Local heart irradiation of ApoE(-/-) mice induces microvascular and endocardial damage and accelerates coronary atherosclerosis

    NARCIS (Netherlands)

    Gabriels, Karen; Hoving, Saske; Seemann, Ingar; Visser, Nils L.; Gijbels, Marion J.; Pol, Jeffrey F.; Daemen, Mat J.; Stewart, Fiona A.; Heeneman, Sylvia

    2012-01-01

    Radiotherapy of thoracic and chest-wall tumors increases the long-term risk of radiation-induced heart disease, like a myocardial infarct. Cancer patients commonly have additional risk factors for cardiovascular disease, such as hypercholesterolemia. The goal of this study is to define the

  11. Plasma interactions with the outboard chamber wall in DIII-D

    International Nuclear Information System (INIS)

    Rudakov, D.L.; Boedo, J.A.; Yu, J.H.; Brooks, N.H.; Fenstermacher, M.E.; Groth, M.; Hollmann, E.M.; Lasnier, C.J.; McLean, A.G.; Moyer, R.A.; Stangeby, P.C.; Tynan, G.R.; Wampler, W.R.; Watkins, J.G.; West, W.P.; Wong, C.P.C.; Bastasz, R.J.; Buchenauer, D.; Whaley, J.

    2009-01-01

    Erosion of the main chamber plasma-facing components is of concern for ITER. Plasma interaction with the outboard chamber wall is studied in DIII-D using Langmuir probes and optical diagnostics. Fast camera data shows that edge localized modes (ELMs) feature helical filamentary structures propagating towards the outboard wall. Upon reaching the wall, filaments result in regions of local intense plasma-material interaction (PMI) where peak incident particle and heat fluxes are up to two orders of magnitude higher than those between ELMs. In low density/collisionality H-mode discharges, PMI at the outboard wall is almost entirely due to ELMs. A moderate change of the gap between the separatrix and the outer wall strongly affects PMI intensity at the wall. Material samples exposed near the outboard wall showed net carbon deposition in high-density discharges (near the Greenwald limit) and tendency towards net erosion in lower density discharges (∼0.45 of the Greenwald limit).

  12. Reduction of heart sound interference from lung sound signals using empirical mode decomposition technique.

    Science.gov (United States)

    Mondal, Ashok; Bhattacharya, P S; Saha, Goutam

    2011-01-01

    During the recording time of lung sound (LS) signals from the chest wall of a subject, there is always heart sound (HS) signal interfering with it. This obscures the features of lung sound signals and creates confusion on pathological states, if any, of the lungs. A novel method based on empirical mode decomposition (EMD) technique is proposed in this paper for reducing the undesired heart sound interference from the desired lung sound signals. In this, the mixed signal is split into several components. Some of these components contain larger proportions of interfering signals like heart sound, environmental noise etc. and are filtered out. Experiments have been conducted on simulated and real-time recorded mixed signals of heart sound and lung sound. The proposed method is found to be superior in terms of time domain, frequency domain, and time-frequency domain representations and also in listening test performed by pulmonologist.

  13. [Plastic surgery of the thoracic wall as a method of thoracic wall reconstruction after complete surgical wound disintegration after sternotomy].

    Science.gov (United States)

    Hájek, T; Jirásek, K; Urban, M; Straka, Z

    1998-12-01

    During the period between January 1996 and July 1998 in our department 1920 patients were operated on account of heart disease from median sternotomy. In 17 patients, i.e. in 0.9% during the early postoperative period the surgical wound disintegrated incl. dehiscence of the sternum and the development of postoperative mediastinitis. In 14 of these patients the authors reconstructed the defect of the thoracic wall by their own modification of Jurkiewicz plastic operation using the pectoral muscles. One patient from this group died, in the remaining 13 patients the wound healed without deformity of the chest and without signs of instability, without restriction of movement and function.

  14. Statistical analysis of the velocity and scalar fields in reacting turbulent wall-jets

    Science.gov (United States)

    Pouransari, Z.; Biferale, L.; Johansson, A. V.

    2015-02-01

    The concept of local isotropy in a chemically reacting turbulent wall-jet flow is addressed using direct numerical simulation (DNS) data. Different DNS databases with isothermal and exothermic reactions are examined. The chemical reaction and heat release effects on the turbulent velocity, passive scalar, and reactive species fields are studied using their probability density functions (PDFs) and higher order moments for velocities and scalar fields, as well as their gradients. With the aid of the anisotropy invariant maps for the Reynolds stress tensor, the heat release effects on the anisotropy level at different wall-normal locations are evaluated and found to be most accentuated in the near-wall region. It is observed that the small-scale anisotropies are persistent both in the near-wall region and inside the jet flame. Two exothermic cases with different Damköhler numbers are examined and the comparison revealed that the Damköhler number effects are most dominant in the near-wall region, where the wall cooling effects are influential. In addition, with the aid of PDFs conditioned on the mixture fraction, the significance of the reactive scalar characteristics in the reaction zone is illustrated. We argue that the combined effects of strong intermittency and strong persistency of anisotropy at the small scales in the entire domain can affect mixing and ultimately the combustion characteristics of the reacting flow.

  15. Cardiac MRI and Transthoracic Echocardiography of Left Ventricular Myocardial Noncompaction in A Patient with Congestive Heart Failure: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Eui Min; Byun, Joo Nam [Chosun University Hospital College of Medicine, Gwangju (Korea, Republic of); Kim, Dong Hun [Soonchunhyang University Hospital Bucheon College of Medicine, Bucheon (Korea, Republic of)

    2010-11-15

    We report a case of a 38-year-old male presenting with new-onset dyspnea, that was diagnosed as left ventricular noncompaction by transthoracic echocardiographic and cardiac MR. The tests revealed left ventricular systolic dysfunction with prominent trabeculations associated with deep intertrabecular recesses and an enddiastolic noncompacted to compacted ratio of 2.5 in the whole apical wall and mid-ventricular anterolateral and inferolateral walls. Delayed gadolinium contrast-enhanced MRI revealed subepicardial mid-wall hyperenhancement of the midventricular anteroseptal and inferoseptal walls, which suggested myocardial fibrosis. We review the pathophysiology, clinical characteristics, and diagnostic approach of the left ventricular noncompaction associated with congestive heart failure

  16. Heart Health - Brave Heart

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Brave Heart Past Issues / Winter 2009 Table of Contents For ... you can have a good life after a heart attack." Lifestyle Changes Surviving—and thriving—after such ...

  17. Application Problems of Anchor Dowels in Reinforced Concrete Shear Wall and Frame Connections

    OpenAIRE

    Musa H. Arslan

    2016-01-01

    Strengthening of the existing seismically deficient reinforced concrete (RC) buildings is an important issue in earthquake prone regions. Addition of RC shear wall as infill or external walls into the structural system has been a commonly preferred strengthening technique since the Big Erzincan Earthquake occurred in Turkey, 1992. The newly added rigid infill walls act primarily as shear walls and relieve the non-ductile existing frames from being subjected to large shear demands providing th...

  18. Structural and functional changes in the heart and clinical features of heart failure with preserved left ventricular ejection fraction in patients after myocardial infarction, comorbided with arterial hypertension

    Directory of Open Access Journals (Sweden)

    V. D. Syvolap

    2013-12-01

    class I, 32% - NYHA class II, 48% - NYHA class III and 10% have NYHA class IV. In the first group revealed a significant increase of left ventricular end diastolic volume (13,8%, p <0,05, left ventricular end systolic volume (14,9%, p <0,05 and left atrial volume index (35%, p <0,05 compared with patients from the second group. Patients from the second group had a significant increase of left ventricular mass index (15,2%, p <0,05, left ventricular posterior wall ( 12,8%, p <0,05 and interventricular septum (10%, p <0,05 compared with patients from the third group. Patients from the first group had a higher E/E ' ratio (26%, p <0,05 compared with patients from the second group. In patients from the second group revealed decreased E/A (30,8%, p <0,05, E '(35,7%, p <0,05 and increased E/E' (13, 3%, p <0,05 compared with patients from the third group. Patients after myocardial infarction with arterial hypertension and diastolic heart failure had diastolic dysfunction mainly on the type of violation of relaxation (74%. 22% of these patients had pseudonormal type of diastolic dysfunction and 4% had restrictive LV filling type. Conclusion: In patients with post-infarction cardiosclerosis and diastolic heart failure with arterial hypertension severity of clinical manifestations of heart failure correlates with left atrial volume index and markers of diastolic dysfunction such as E' and E/E'. In patients with post-infarction cardiosclerosis and arterial hypertension with diastolic heart failure had predominantly concentric hypertrophy with increased left atrial volume index and moderate left ventricular dilatation and mild diastolic dysfunction. In patients after myocardial infarction with arterial hypertension and asymptomatic diastolic dysfunction observed structural and functional changes in the type of concentric hypertrophy with thickened walls and increased left ventricular mass index.

  19. Reconstruction and Visualization of Fiber and Laminar Structure in the Normal Human Heart from Ex Vivo DTMRI Data

    International Nuclear Information System (INIS)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-01-01

    Background--The human heart is composed of a helical network of muscle fibers. These fibers are organized to form sheets that are separated by cleavage surfaces. This complex structure of fibers and sheets is responsible for the orthotropic mechanical properties of cardiac muscle. The understanding of the configuration of the 3D fiber and sheet structure is important for modeling the mechanical and electrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling after myocardial infarction. Methods--Anisotropic least square filtering followed by fiber and sheet tracking techniques were applied to Diffusion Tensor Magnetic Resonance Imaging (DTMRI) data of the excised human heart. The fiber configuration was visualized by using thin tubes to increase 3-dimensional visual perception of the complex structure. The sheet structures were reconstructed from the DTMRI data, obtaining surfaces that span the wall from the endo- to the epicardium. All visualizations were performed using the high-quality ray-tracing software POV-Ray. Results--The fibers are shown to lie in sheets that have concave or convex transmural structure which correspond to histological studies published in the literature. The fiber angles varied depending on the position between the epi- and endocardium. The sheets had a complex structure that depended on the location within the myocardium. In the apex region the sheets had more curvature. Conclusions--A high-quality visualization algorithm applied to demonstrated high quality DTMRI data is able to elicit the comprehension of the complex 3 dimensional structure of the fibers and sheets in the heart

  20. Take heart!

    CERN Multimedia

    Alizée Dauvergne

    2010-01-01

    Recently, ten new semi-automatic defibrillators were installed at various locations around CERN. This is a preventive measure intended to provide cardiac arrest victims with the best possible response. The first responder could be you!   The Director-General has welcomed the initiative of the Medical Service and Fire Brigade for the installation of ten new semi-automatic defibrillators. You have probably seen them on your way to the restaurant, for example:  brand new semi-automatic defibrillators, ready for an emergency. Housed in a white wall-mounted case, the bright red defibrillators are marked with a white heart symbol crossed by a lightning bolt (see photo). The defibrillator is designed so that anyone can use it. “Anyone can use it, you don’t need to be a health professional,” says Dr Reymond from CERN's Medical Service. Together with the CERN Fire Brigade, he is behind the initiative to have these units put in place. And with good reason, as the unit...

  1. Right ventricular longitudinal strain and right ventricular stroke work index in patients with severe heart failure: left ventricular assist device suitability for transplant candidates.

    Science.gov (United States)

    Cameli, M; Bernazzali, S; Lisi, M; Tsioulpas, C; Croccia, M G; Lisi, G; Maccherini, M; Mondillo, S

    2012-09-01

    Right ventricular (RV) systolic function has a critical role in determining the clinical outcome and the success of using left ventricular assist devices in patients with refractory heart failure. RV deformation analysis by speckle tracking echocardiography (STE) has recently allowed the analysis of RV longitudinal function. Using cardiac catheterization as the reference standard, this study aimed to explore the correlation between RV longitudinal function by STE and RV stroke work index (RVSWI) among patients referred for cardiac transplantation. Right heart catheterization and transthoracic echo-Doppler were simultaneously performed in 47 patients referred for cardiac transplant assessment due to refractory heart failure (ejection fraction 25.1 ± 4.5%). Thermodilution RV stroke volume and invasive pulmonary pressures were used to obtain RVSWI. RV longitudinal strain (RVLS) by STE was assessed averaging RV free-wall segments (free-wall RVLS). We also calculated. Tricuspid S' and tricuspid annular plane systolic excursion (TAPSE). No significant correlation was observed for TAPSE on tricuspid S' with RV stroke volume (r = 0.14 and r = 0.06, respectively). A close negative correlation between free-wall RVLS and RVSWI was found (r = -0.82; P rights reserved.

  2. Sub-hectare crop area mapped wall-to-wall in Tigray Ethiopia with HEC processing of WorldView sub-meter panchromatic image texture

    Science.gov (United States)

    Neigh, C. S. R.; Carroll, M.; Wooten, M.; McCarty, J. L.; Powell, B.; Husak, G. J.; Enenkel, M.; Hain, C.

    2017-12-01

    Global food production in the developing world occurs within sub-hectare fields that are difficult to identify with moderate resolution satellite imagery. Knowledge about the distribution of these fields is critical in food security programs. We developed a semi-automated image segmentation approach using wall-to-wall sub-meter imagery with high-end computing (HEC) to map crop area (CA) throughout Tigray, Ethiopia that encompasses over 41,000 km2. Our approach tested multiple HEC processing streams to reduce processing time and minimize mapping error. We applied multiple resolution smoothing kernels to capture differences in land surface texture associated to CA. Typically, very-small fields (mean big-data methodology to extract wall-to-wall CA for other regions of the world that have very-small agriculture fields with similar image texture.

  3. [The role of natriuretic peptides in heart failure].

    Science.gov (United States)

    Ancona, R; Limongelli, G; Pacileo, G; Miele, T; Rea, A; Roselli, T; Masarone, D; Messina, S; Palmieri, R; Golia, E; Iacomino, M; Gala, S; Calabrò, P; Di Salvo, G; Calabrò, R

    2007-10-01

    Over the last decades, there has been a significant increase in incidence and prevalence of heart failure, a major cause of cardiac morbidity and mortality. Measurements of neurohormones, in particular B-type natriuretic peptide (BNP), can significantly improve diagnostic accuracy, and also correlate with long-term morbidity and mortality in patients with chronic heart failure presenting to the emergency department. BNP is secreted by cardiac ventricles mainly in response to wall stress and neurohormonal factors like the sympathetic nervous system, endothelins, and the rennin-angiotensin-aldosterone system. BNP increases myocardial relaxation and oppose the vasoconstrictive, sodium retaining, and natriuretic effects caused by vasoconstrictive factors. BNP is the first biomarker to prove its clinical value for the diagnosis of left ventricular systolic and diastolic dysfunction but also for the right ventricular dysfunction, guiding prognosis and therapy management. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.

  4. Correlates of lung/heart ratio of thallium-201 in coronary artery disease

    International Nuclear Information System (INIS)

    Homma, S.; Kaul, S.; Boucher, C.A.

    1987-01-01

    We studied 306 patients with chest pain (262 with coronary artery disease and 44 with no coronary artery disease) to determine which of 23 clinical, exercise, thallium, and angiographic variables best discriminate between patients with increased lung/heart ratios of thallium versus those with normal ratios. Normal lung/heart ratio values were defined using an additional 45 subjects with less than 1% probability of coronary artery disease. The number of diseased vessels was the best discriminator between patients with increased ratios versus those with normal ratios. Double product at peak exercise, number of segments with abnormal wall motion, patient gender, and duration of exercise were also significant discriminators. Using discriminant function analysis these variables could correctly identify 81% of cases with increased lung/heart ratios and 72% of cases with normal ratios. These results indicate that an increased lung/heart ratio of thallium reflects exercise-induced left ventricular dysfunction and affords a better understanding of why this thallium parameter is a powerful prognostic indicator in patients with chest pain

  5. Association Mapping of Cell Wall Synthesis Regulatory Genes and Cell Wall Quality in Switchgrass

    Energy Technology Data Exchange (ETDEWEB)

    Bartley, Laura [Univ. of Oklahoma, Norman, OK (United States). Dept. of Microbiology and Plant Biology; Wu, Y. [Oklahoma State Univ., Stillwater, OK (United States); Zhu, L. [Oklahoma State Univ., Stillwater, OK (United States); Brummer, E. C. [Noble Foundation, Ardmore, OK (United States); Saha, M. [Noble Foundation, Ardmore, OK (United States)

    2016-05-31

    markers might be used to select switchgrass genotypes with improved composition in breeding programs for biofuel and forage production. Because the SSAC continues to be characterized by collaborators in the bioenergy community, the data generated will be used to identify additional markers in higher resolution genotyping data to approach identifying the genes and alleles that cause natural variation in switchgrass cell wall quality. For example, these markers can be surveyed in the 2100-member Oklahoma Southern and Northern Lowland switchgrass collections that this project also characterized. An orthogonal approach to biodiversity studies, using comparative functional genomics permits systematic querying of how much regulatory information is likely to be transferable from dicots to grasses and use of accumulated functional genomics resources for better-characterized grass species, such as rice, itself a biomass source in global agriculture and in certain regions. The project generated and tested a number of specific hypotheses regarding cell wall transcription factors and enzymes of grasses. To aid identification of cell wall regulators, the project assembled a novel, highdepth and -quality gene association network using a general linearized model scoring system to combine rice gene network data. Using known or putative orthologs of Arabidopsis cell wall biosynthesis genes and regulators, the project pulled from this network a cell wall sub-network that includes 96 transcription factors. Reverse genetics of a co-ortholog of the Arabidopsis MYB61 transcription factor in rice revealed that this regulatory node has evolved the ability to regulate grass-specific cell wall synthesis enzymes. A transcription factor with such activity has not been previously characterized to our knowledge, representing a major conclusion of this work. Changes in gene expression in a protoplast-based assay demonstrated positive or negative roles in cell wall regulation for eleven other

  6. Theoretical Study of α-V2O5 -Based Double-Wall Nanotubes.

    Science.gov (United States)

    Porsev, Vitaly V; Bandura, Andrei V; Evarestov, Robert A

    2015-10-05

    First-principles calculations of the atomic and electronic structure of double-wall nanotubes (DWNTs) of α-V2 O5 are performed. Relaxation of the DWNT structure leads to the formation of two types of local regions: 1) bulk-type regions and 2) puckering regions. Calculated total density of states (DOS) of DWNTs considerably differ from that of single-wall nanotubes and the single layer, as well as from the DOS of the bulk and double layer. Small shoulders that appear on edges of valence and conduction bands result in a considerable decrease in the band gaps of the DWNTs (up to 1 eV relative to the single-layer gaps). The main reason for this effect is the shift of the inner- and outer-wall DOS in opposite directions on the energetic scale. The electron density corresponding to shoulders at the conduction-band edges is localized on vanadium atoms of the bulk-type regions, whereas the electron density corresponding to shoulders at the valence-band edges belongs to oxygen atoms of both regions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Stabilization of mitochondrial membrane potential prevents doxorubicin-induced cardiotoxicity in isolated rat heart

    International Nuclear Information System (INIS)

    Montaigne, David; Marechal, Xavier; Baccouch, Riadh; Modine, Thomas; Preau, Sebastien; Zannis, Konstantinos; Marchetti, Philippe; Lancel, Steve; Neviere, Remi

    2010-01-01

    The present study was undertaken to examine the effects of doxorubicin on left ventricular function and cellular energy state in intact isolated hearts, and, to test whether inhibition of mitochondrial membrane potential dissipation would prevent doxorubicin-induced mitochondrial and myocardial dysfunction. Myocardial contractile performance and mitochondrial respiration were evaluated by left ventricular tension and its first derivatives and cardiac fiber respirometry, respectively. NADH levels, mitochondrial membrane potential and glucose uptake were monitored non-invasively via epicardial imaging of the left ventricular wall of Langendorff-perfused rat hearts. Heart performance was reduced in a time-dependent manner in isolated rat hearts perfused with Krebs-Henseleit solution containing 1 μM doxorubicin. Compared with controls, doxorubicin induced acute myocardial dysfunction (dF/dt max of 105 ± 8 mN/s in control hearts vs. 49 ± 7 mN/s in doxorubicin-treated hearts; *p < 0.05). In cardiac fibers prepared from perfused hearts, doxorubicin induced depression of mitochondrial respiration (respiratory control ratio of 4.0 ± 0.2 in control hearts vs. 2.2 ± 0.2 in doxorubicin-treated hearts; *p < 0.05) and cytochrome c oxidase kinetic activity (24 ± 1 μM cytochrome c/min/mg in control hearts vs. 14 ± 3 μM cytochrome c/min/mg in doxorubicin-treated hearts; *p < 0.05). Acute cardiotoxicity induced by doxorubicin was accompanied by NADH redox state, mitochondrial membrane potential, and glucose uptake reduction. Inhibition of mitochondrial permeability transition pore opening by cyclosporine A largely prevented mitochondrial membrane potential dissipation, cardiac energy state and dysfunction. These results suggest that in intact hearts an impairment of mitochondrial metabolism is involved in the development of doxorubicin cardiotoxicity.

  8. Avaliação quantitativa da movimentação parietal regional do ventrículo esquerdo na endomiocardiofibrose Quantitative assessment of left ventricular regional wall motion in endomyocardial fibrosis

    Directory of Open Access Journals (Sweden)

    Charles Mady

    2005-03-01

    Full Text Available OBJETIVO: Analisar a movimentação parietal regional do ventrículo esquerdo (VE em pacientes com endomiocardiofibrose (EMF. MÉTODOS: Estudados 88 pacientes, 59 do sexo feminino, com idade média de 39±13 anos (variação de 9 a 65 com evidência ecocardiográfica e angiográfica de EMF do VE. A intensidade da deposição de tecido fibroso na cineventriculografia contrastada foi classificada como discreta, moderada ou importante. A fração de ejeção global do ventrículo esquerdo (FEVE foi determinada pelo método área-comprimento por meio da ventriculografia. O movimento foi medido em 100 cordas eqüidistantes e perpendiculares à linha média desenhada no meio dos contornos diastólico e sistólico finais e normalizadas para o tamanho cardíaco. Analisaram-se cinco segmentos do VE: A - apical; AL - ântero-lateral; AB - ântero-basal; IA - ínfero-apical; IB - ínfero-basal. A anormalidade foi expressa em unidades de desvio padrão do movimento médio em uma população de referência normal, composta por 103 pacientes com VE normal, conforme dados de clínica, eletrocardiograma e padrões angiográficos. RESULTADOS: A FEVE média foi de 0,47±0,12. O envolvimento de tecido fibroso do VE foi discreto em 12 pacientes, moderado em 40 e importante em 36. As regiões com pior movimentação parietal foram A (-1,4±1,6 desvio-padrão/cordas e IA (-1,6±1,8 desvio-padrão/cordas comparadas com AB (-0,3±1,9 desvio-padrão /cordas, AL (-0,5±1,8 desvio-padrão/cordas e IB (-0,9±1,3 desvio-padrão/cordas. Não se observou relação entre a intensidade de envolvimento do tecido fibroso e a manutenção parietal regional. CONCLUSÃO : Existe alteração da movimentação parietal regional na EMF e é independente da intensidade de deposição de tecido fibroso avaliada qualitativamente. O envolvimento não uniforme do VE deve ser levado em conta no planejamento cirúrgico dessa doença.OBJECTIVE: To analyze left ventricular (LV regional wall

  9. Assessment of automatic quantification of myocardial perfusion and left ventricular function derived from ECG gated myocardial SPECT with {sup 99m}Tc-tetrofosmin in ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Mitsunori; Habara, Hirokazu; Tatsuno, Hironari; Fukuda, Hiroshi; Hamada, Noriko; Kazatani, Yukio [Ehime Prefectural Central Hospital (Japan)

    1999-09-01

    Non-invasive assessment of ischemic heart disease (IHD) requires information of both myocardial perfusion and left ventricular (LV) function. Recently, automatic quantification of ECG-gated myocardial scintigraphy with {sup 99m}Tc-tetrofosmin (QGS) can provide both of them. QGS, coronary angiograms (CAG) and left venticulograms (LVG) were performed in 83 patients with severe IHD in same period. Significant stenosis of coronary artery in CAG were assessed by QGS. The sensitivity, specificity and accuracy of significant stenosis by QGS was excellent (85%, 93% and 88%). The LV end-distolic and end-systolic volumes (EDV and ESV), LV ejection fraction (EF) and regional LV wall motion determined by QGS were compared to LVG. There was a good correlation between the values obtained from QGS and LVG (EDV: r=0.86, ESV: r=0.94, EF: r=0.84, p<0.0001), but QGS tended to underestimate EDV and EF. High complete agreement of regional LV wall motion was gained with 427 (74.0%) out of total 581 segments. In conclusion, QGS data was considered to be useful for assessment of determine significant stenosis and LV function in severe IHD. (author)

  10. Use of the breast board in the radiation treatment of breast cancer on chest wall and regional lymph nodes

    International Nuclear Information System (INIS)

    Shepherd, G.S.; Krishnan, L.; Dean, R.D.; Evans, R.G.

    1987-01-01

    Optimal treatment of the breast or chest wall and regional nodes for carcinoma of the breast is complex and time consuming. A variable angled breast board has been designed to address some of the problems responsible for complications. It has three adjustable inclinations, two L-arm locations with adjustable heights, support to the contralateral arm, and a cassette holder for port films and treatment verification. The design of the board is such that it enables us to reproduce treatment position with relative ease without sacrificing the quality of treatment. Approximately 75 patients have been treated, and to date no complications due to positional error have been documented

  11. Extrapleural Inner Thoracic Wall Lesions: Multidetector CT Findings

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Soo; Kim, Young Tong; Jou, Sung Shik [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of)

    2010-06-15

    The extrapleural space is external to the parietal pleura in the thorax. The structures within and adjacent to this region include the fat pad, endothoracic fascia, intercostal muscles, connective tissue, nerves, vessels, and ribs. Further, the space is divided into the inner and outer thoracic wall by the innermost intercostal muscle. Extrapleural lesions in the inner thoracic wall are classified as air-containing lesions, fat-containing lesions, and soft tissue-containing lesions according on their main component. Air-containing lesions include extrapleural air from direct chest trauma and extrapleural extension from pneumomediastinum. Prominent extrapleural fat is seen in decreased lung volume conditions, and can also be seen in normal individuals. Soft tissue-containing lesions include extrapleural extensions from a pleural or chest wall infection as well as tumors and extrapleural hematoma. We classify extrapleural lesions in the inner thoracic wall and illustrate their imaging findings

  12. [Considerations on local-regional anesthesia for ambulatory tooth extractions in patients with heart disease].

    Science.gov (United States)

    Debernardi, G; Borgogna, E

    1975-01-01

    Ambulatory dental extraction was performed on 150 patients with various forms of heart disease. No serious complications were noted with an anaesthetic without vasoconstriction (plain 3% carbocaine). The prior history was carefully studied and pressure values were determined. It is felt that heart disease does not form an absolute contraindication to ambulatory dental extraction.

  13. Scintigraphy of the heart using sup(99m)Tc diphosphonate in combination with selective coronary perfusion scintigraphy and coronaroangiography

    International Nuclear Information System (INIS)

    Neumann, G.; Trenckmann, H.; Duck, H.J.; Katzschmann, R.; Neugebauerova, A.; Schneider, G.; Gottschild, D.

    1980-01-01

    In 45 patients with ischemic heart disease the results obtained by myocardial scintigraphy using technetium-99m diphosphonate (Tc-99m-DP) were compared with those obtained at selective coronary angiography and selective coronary perfusion scintigraphy. The cumulation of activity in the heart muscle was seen in twelve patients. This group is analyzed in the present paper in more detail. The ventriculographic examination of the left ventricle showed disturbed motility of the wall in six patients, of whom five had a positive myocardial scintigram. In view of this, myocardial scintigraphy using Tc-99m-DP may be considered a complementary, non-invasive method for proving significant disturbances of the motility of the heart wall. Positive myocardial scintigrams were also found in angna pectoris, in a patient after aorto-coronary bypass, in cardiomyopathy and myocarditis. In view of the fact that myocardial scintigraphy using Tc-99m-DP is capable of proving disturbances of cells of the heart muscle taking place at the moment, conclusions can be drawn as to the activity in the heart muscle. It further follows that myocardial scintigraphy may be significant in indicating the aorto-coronary bypass. We failed to prove an unequivocal correlation between myocardial scintigraphy, the number of sclerotically changed coronary vessels and the degree of their narrowing. An immediate relationship could not be proved between the extent of perfusion disturbance and the results of myocardial scintigraphy

  14. Heart disease among children with HIV/AIDS attending the ...

    African Journals Online (AJOL)

    Background: There are very few published studies of heart disease in HIV infected children living in sub-Saharan Africa, a region with more than 50% of the world's population of HIV infected patients. Objectives: To determine the prevalence, and describe the type and clinical presentation of heart disease among children ...

  15. Reasons for the lack of benefit of immediate angioplasty during recombinant tissue plasminogen activator therapy for acute myocardial infarction: a regional wall motion analysis. European Cooperative Study Group

    NARCIS (Netherlands)

    Arnold, A. E.; Serruys, P. W.; Rutsch, W.; Simoons, M. L.; de Bono, D. P.; Tijssen, J. G.; Lubsen, J.; Verstraete, M.

    1991-01-01

    Regional ventricular wall motion analysis utilizing three different methods was performed on predischarge left ventriculograms from 291 of 367 patients enrolled in a randomized trial of single chain recombinant tissue-type plasminogen activator (rt-PA), aspirin and heparin with and without immediate

  16. Assessment of cardiac performance with quantitative radionuclide angiocardiography: sequential left ventricular ejection fraction, normalized left ventricular ejection rate, and regional wall motion

    International Nuclear Information System (INIS)

    Marshall, R.C.; Berger, H.J.; Costin, J.C.; Freedman, G.S.; Wolberg, J.; Cohen, L.S.; Gotischalk, A.; Zaret, B.L.

    1977-01-01

    Sequential quantitative first pass radionuclide angiocardiograms (RA) were used to measure left ventricular ejection fraction (LVEF) and left ventricular ejection rate (LVER), and to assess regional wall motion (RWM) in the anterior (ANT) and left anterior oblique (LAO) positions. Studies were obtained with a computerized multicrystal scintillation camera suitable for acquiring high count-rate data. Background was determined in a new fashion by selecting frames temporally from the left ventricular region of interest time-activity curve. A ''representative'' cardiac cycle was formed by summing together counts over three to six cardiac cycles. From this background corrected, high count-rate ''representative''cardiac cycle, LVEF, LVER, and RWM were determined. In 22 patients with normal sinus rhythm in the absence of significant valvular regurgitation, RA LVEF correlated well with that measured by contrast angiography (r = 0.95). LVER correlated well with LVEF measured at contrast angiography (r = 0.90) and allowed complete separation of those with normal (LVER = 3.4 +- 0.17 sec -1 ) and abnormal (LVER = 1.22 +- 0.11 sec -1 ) (P < 0.001) left ventricular performance. This separation was independent of background. Isoproterenol infusion in five normal subjects caused LVER to increase by 81 +- 17% while LVEF increased by 10 +- 2.0%. RWM was correctly defined in 21/22 patients and 89% of left ventricular segments with abnormal wall motion

  17. Characteristics of wall pressure over wall with permeable coating

    Energy Technology Data Exchange (ETDEWEB)

    Song, Woo Seog; Shin, Seungyeol; Lee, Seungbae [Inha Univ., Incheon (Korea, Republic of)

    2012-11-15

    Fluctuating wall pressures were measured using an array of 16 piezoelectric transducers beneath a turbulent boundary layer. The coating used in this experiment was an open cell, urethane type foam with a porosity of approximately 50 ppi. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The boundary layer on the flat plate was measured by using a hot wire probe, and the CPM method was used to determine the skin friction coefficient. The wall pressure autospectra and streamwise wavenumber frequency spectra were compared to assess the attenuation of the wall pressure field by the coating. The coating is shown to attenuate the convective wall pressure energy. However, the relatively rough surface of the coating in this investigation resulted in a higher mean wall shear stress, thicker boundary layer, and higher low frequency wall pressure spectral levels compared to a smooth wall.

  18. Segmental wall motion abnormalities in dilated cardiomyopathy: hemodynamic characteristics and comparison with thallium-201 myocardial scintigraphy

    International Nuclear Information System (INIS)

    Yamaguchi, S.; Tsuiki, K.; Hayasaka, M.; Yasui, S.

    1987-01-01

    This study assessed the hemodynamic characteristics of segmental wall motion abnormality of the left ventricle in patients with dilated cardiomyopathy (DCM) and its relation to the thallium-201 (TI-201) myocardial scintigraphy (MPI). Left ventriculograms and MPI in 23 patients were analyzed by the use of quantitative indexes of regional wall motion and TI-201 uptake based on a mean and a standard deviation of 13 normal subjects. Relative normokinesis in our definition was more frequently seen in the inferior wall than in the anterior wall (p less than 0.01). In contrast, severe asynergy was more often seen in the anterior wall than in the inferior wall (p less than 0.01). There were 11 patients who had relative normokinesis and asynergy together. By means of the index of wall motion, the DCM patients were divided into two groups, one with segmental wall motion abnormality (SWMA) and another with diffuse wall motion abnormality (DWMA). The DWMA group had higher left ventricular end-diastolic pressures (p less than 0.05) and the tendency of large left ventricular end-diastolic volumes than the SWMA group. There was a rough correlation (r = 0.58) between the quantitative indexes of TI-201 uptake and wall motion at the same region of the left ventricle. Thus, the nonuniformity of the left ventricular wall motion was recognized in the patients with DCM and more increased preload was shown in the patients with DWMA than in the group with SWMA. Further, the regional asynergy may be related to the localized fibrosis within the left ventricle in DCM, considering the result that the worse TI-201 uptake was roughly accompanied by the more severe asynergy

  19. Role of Myocardial Collagen in Severe Aortic Stenosis With Preserved Ejection Fraction and Symptoms of Heart Failure.

    Science.gov (United States)

    Echegaray, Kattalin; Andreu, Ion; Lazkano, Ane; Villanueva, Iñaki; Sáenz, Alberto; Elizalde, María Reyes; Echeverría, Tomás; López, Begoña; Garro, Asier; González, Arantxa; Zubillaga, Elena; Solla, Itziar; Sanz, Iñaki; González, Jesús; Elósegui-Artola, Alberto; Roca-Cusachs, Pere; Díez, Javier; Ravassa, Susana; Querejeta, Ramón

    2017-10-01

    We investigated the anatomical localization, biomechanical properties, and molecular phenotype of myocardial collagen tissue in 40 patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure. Two transmural biopsies were taken from the left ventricular free wall. Mysial and nonmysial regions of the collagen network were analyzed. Myocardial collagen volume fraction (CVF) was measured by picrosirius red staining. Young's elastic modulus (YEM) was measured by atomic force microscopy in decellularized slices to assess stiffness. Collagen types I and III were measured as C I VF and C III VF, respectively, by confocal microscopy in areas with YEM evaluation. Compared with controls, patients exhibited increased mysial and nonmysial CVF and nonmysial:mysial CVF ratio (P < .05). In patients, nonmysial CVF (r = 0.330; P = .046) and the nonmysial:mysial CVF ratio (r = 0.419; P = .012) were directly correlated with the ratio of maximal early transmitral flow velocity in diastole to early mitral annulus velocity in diastole. Both the C I VF:C III VF ratio and YEM were increased (P ≤ .001) in nonmysial regions compared with mysial regions in patients, with a direct correlation (r = 0.895; P < .001) between them. These findings suggest that, in patients with severe aortic stenosis with preserved ejection fraction and symptoms of heart failure, diastolic dysfunction is associated with increased nonmysial deposition of collagen, predominantly type I, resulting in increased extracellular matrix stiffness. Therefore, the characteristics of collagen tissue may contribute to diastolic dysfunction in these patients. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  20. Bridging the divide: Middle Eastern walls and fences and the spatial governance of problem populations

    NARCIS (Netherlands)

    Pallister-Wilkins, P.

    2015-01-01

    Building on a long history of spatial control through walling in the region, walls and fences have been built in the Middle East in recent years to undertake a range of practices. Gated communities, residential and security compounds, anti-migrant walls, separation barriers and counter-insurgency

  1. Reconstruction and Visualization of Fiber and Laminar Structure inthe Normal Human Heart from Ex Vivo DTMRI Data

    Energy Technology Data Exchange (ETDEWEB)

    Rohmer, Damien; Sitek, Arkadiusz; Gullberg, Grant T.

    2006-12-18

    Background - The human heart is composed of a helicalnetwork of muscle fibers. These fibers are organized to form sheets thatare separated by cleavage surfaces. This complex structure of fibers andsheets is responsible for the orthotropic mechanical properties ofcardiac muscle. The understanding of the configuration of the 3D fiberand sheet structure is important for modeling the mechanical andelectrical properties of the heart and changes in this configuration maybe of significant importance to understand the remodeling aftermyocardial infarction.Methods - Anisotropic least square filteringfollowed by fiber and sheet tracking techniques were applied to DiffusionTensor Magnetic Resonance Imaging (DTMRI) data of the excised humanheart. The fiber configuration was visualized by using thin tubes toincrease 3-dimensional visual perception of the complex structure. Thesheet structures were reconstructed from the DTMRI data, obtainingsurfaces that span the wall from the endo- to the epicardium. Allvisualizations were performed using the high-quality ray-tracing softwarePOV-Ray. Results - The fibers are shown to lie in sheets that haveconcave or convex transmural structure which correspond to histologicalstudies published in the literature. The fiber angles varied depending onthe position between the epi- and endocardium. The sheets had a complexstructure that depended on the location within the myocardium. In theapex region the sheets had more curvature. Conclusions - A high-qualityvisualization algorithm applied to demonstrated high quality DTMRI datais able to elicit the comprehension of the complex 3 dimensionalstructure of the fibers and sheets in the heart.

  2. Lung capillary injury and repair in left heart disease: a new target for therapy?

    Science.gov (United States)

    Azarbar, Sayena; Dupuis, Jocelyn

    2014-07-01

    The lungs are the primary organs affected in LHD (left heart disease). Increased left atrial pressure leads to pulmonary alveolar-capillary stress failure, resulting in cycles of alveolar wall injury and repair. The reparative process causes the proliferation of MYFs (myofibroblasts) with fibrosis and extracellular matrix deposition, resulting in thickening of the alveolar wall. Although the resultant reduction in vascular permeability is initially protective against pulmonary oedema, the process becomes maladaptive causing a restrictive lung syndrome with impaired gas exchange. This pathological process may also contribute to PH (pulmonary hypertension) due to LHD. Few clinical trials have specifically evaluated lung structural remodelling and the effect of related therapies in LHD. Currently approved treatment for chronic HF (heart failure) may have direct beneficial effects on lung structural remodelling. In the future, novel therapies specifically targeting the remodelling processes may potentially be utilized. In the present review, we summarize data supporting the clinical importance and pathophysiological mechanisms of lung structural remodelling in LHD and propose that this pathophysiological process should be explored further in pre-clinical studies and future therapeutic trials.

  3. Regional variance of visually lossless threshold in compressed chest CT images: Lung versus mediastinum and chest wall

    International Nuclear Information System (INIS)

    Kim, Tae Jung; Lee, Kyoung Ho; Kim, Bohyoung; Kim, Kil Joong; Chun, Eun Ju; Bajpai, Vasundhara; Kim, Young Hoon; Hahn, Seokyung; Lee, Kyung Won

    2009-01-01

    Objective: To estimate the visually lossless threshold (VLT) for the Joint Photographic Experts Group (JPEG) 2000 compression of chest CT images and to demonstrate the variance of the VLT between the lung and mediastinum/chest wall. Subjects and methods: Eighty images were compressed reversibly (as negative control) and irreversibly to 5:1, 10:1, 15:1 and 20:1. Five radiologists determined if the compressed images were distinguishable from their originals in the lung and mediastinum/chest wall. Exact tests for paired proportions were used to compare the readers' responses between the reversible and irreversible compressions and between the lung and mediastinum/chest wall. Results: At reversible, 5:1, 10:1, 15:1, and 20:1 compressions, 0%, 0%, 3-49% (p < .004, for three readers), 69-99% (p < .001, for all readers), and 100% of the 80 image pairs were distinguishable in the lung, respectively; and 0%, 0%, 74-100% (p < .001, for all readers), 100%, and 100% were distinguishable in the mediastinum/chest wall, respectively. The image pairs were less frequently distinguishable in the lung than in the mediastinum/chest wall at 10:1 (p < .001, for all readers) and 15:1 (p < .001, for two readers). In 321 image comparisons, the image pairs were indistinguishable in the lung but distinguishable in the mediastinum/chest wall, whereas there was no instance of the opposite. Conclusion: For JPEG2000 compression of chest CT images, the VLT is between 5:1 and 10:1. The lung is more tolerant to the compression than the mediastinum/chest wall.

  4. Regional variance of visually lossless threshold in compressed chest CT images: Lung versus mediastinum and chest wall

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Jung [Department of Radiology, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea, Republic of); Lee, Kyoung Ho [Department of Radiology, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea, Republic of)], E-mail: kholee@snubhrad.snu.ac.kr; Kim, Bohyoung; Kim, Kil Joong; Chun, Eun Ju; Bajpai, Vasundhara; Kim, Young Hoon [Department of Radiology, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea, Republic of); Hahn, Seokyung [Medical Research Collaborating Center, Seoul National University Hospital, 28 Yongon-dong, Chongno-gu, Seoul 110-744 (Korea, Republic of); Seoul National University College of Medicine (Korea, Republic of); Lee, Kyung Won [Department of Radiology, Seoul National University Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do 463-707 (Korea, Republic of); Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center (Korea, Republic of)

    2009-03-15

    Objective: To estimate the visually lossless threshold (VLT) for the Joint Photographic Experts Group (JPEG) 2000 compression of chest CT images and to demonstrate the variance of the VLT between the lung and mediastinum/chest wall. Subjects and methods: Eighty images were compressed reversibly (as negative control) and irreversibly to 5:1, 10:1, 15:1 and 20:1. Five radiologists determined if the compressed images were distinguishable from their originals in the lung and mediastinum/chest wall. Exact tests for paired proportions were used to compare the readers' responses between the reversible and irreversible compressions and between the lung and mediastinum/chest wall. Results: At reversible, 5:1, 10:1, 15:1, and 20:1 compressions, 0%, 0%, 3-49% (p < .004, for three readers), 69-99% (p < .001, for all readers), and 100% of the 80 image pairs were distinguishable in the lung, respectively; and 0%, 0%, 74-100% (p < .001, for all readers), 100%, and 100% were distinguishable in the mediastinum/chest wall, respectively. The image pairs were less frequently distinguishable in the lung than in the mediastinum/chest wall at 10:1 (p < .001, for all readers) and 15:1 (p < .001, for two readers). In 321 image comparisons, the image pairs were indistinguishable in the lung but distinguishable in the mediastinum/chest wall, whereas there was no instance of the opposite. Conclusion: For JPEG2000 compression of chest CT images, the VLT is between 5:1 and 10:1. The lung is more tolerant to the compression than the mediastinum/chest wall.

  5. On the Partitioning of Wall Heat Flux in Subcooled Flow Boiling

    International Nuclear Information System (INIS)

    Chu, In-Cheol; Hoang, Nhan Hien; Euh, Dong-Jin; Song, Chul-Hwa

    2015-01-01

    This region has been treated successfully by two-fluid model coupled with a population balance model or interfacial area transport equation (IATE). The second region is near-wall heat transfer which has been commonly described by a wall heat flux partitioning model coupled with models of nucleation site density (NSD), bubble departure diameter and bubble release frequency. Since the phase change process in the near-wall heat transfer is really complex, comprising different heat transfer mechanisms, bubble dynamics, bubble nucleation and thermal response of heated surface, the modeling of the second region is still a great challenge despite intensive efforts. Numerous models and correlations have been proposed to aim for computing the near-wall heat transfer. The models of nucleation site density, bubble departure diameter and bubble release frequency are used to quantify these components. The models closely related to each other. The heat flux partitioning model controls the wall and liquid temperatures. Then, it turns to control the boiling parameters, i.e. nucleation site density, bubble departure diameter and bubble release frequency. In this study, the partitioning of wall heat flux is taken into account. The existing issues occurred with previous models of the heat flux partitioning are pointed out and then a new model which considers the heat transfer caused by evaporation of superheated liquid at bubble boundary and the actual period of transient conduction term is formulated. The new model is then validated with a collected experimental database. This paper presented a new heat flux partitioning model in which the heat transfer by evaporation of the superheated liquid at the bubble boundary and the active period of the transient conduction were considered. The new model was validated with the experimental data of the subcooled flow boiling of water obtained by Phillips

  6. Study of prevalence & risk factors of congenital heart defect (Review Article

    Directory of Open Access Journals (Sweden)

    ali dehghani

    2017-09-01

    Full Text Available Abstract Background: Congenital heart defects are known as the state that comes from birth and influences on structure and function of baby's heart, The different types of defects can range from mild (e.g., a small hole between the heart chambers to hard (like a flaw or weakness in a part of the heart. Method: This article is a review article in which the articles published in Farsi and English that the bases valid as Medline, Google Scholar, Pubmed, Springer, SID index has been used, as well as for the study of keywords associated with the use of MESH keywords in identifying and no time limit listed in the databases were searched. Result The prevalence of congenital heart defect, in general, less than one per cent in newborn. The ventricular wall abnormalities defect (VSD, atrial septal defect of (ASD, patent ductus arteriosus (PDA and tetralogy of Fallot (TOF Top among the most types of congenital heart anomalies. Factors such as the age of the parents at conception, maternal risk of diabetes, influenza and febrile illness during pregnancy, drug use during pregnancy and taking a multivitamin before and during the Pregnancy were influenced of newborns with congenital heart defects. Conclusion: According to studies need to be conducted in the presence of multiple risk factors for these disorders, seem to have a detailed plan to Study of More about the factors that affect the risk of developing these disorders, as well as interventions to reduce risk factors identified particularly during pregnancy.

  7. Influence of age on the prognostic importance of left ventricular dysfunction and congestive heart failure on long-term survival after acute myocardial infarction. TRACE Study Group

    DEFF Research Database (Denmark)

    Køber, L; Torp-Pedersen, C; Ottesen, M

    1996-01-01

    for entry into the TRAndolapril Cardiac Evaluation (TRACE) study. Medical history, echocardiographic estimation of LV systolic function determined as wall motion index, infarct complications, and survival were documented for all patients. To study the importance of congestive heart failure and wall motion...... dysfunction was more pronounced in the elderly than in the young....

  8. Pathology of radiation pancarditis. Cardiac lesions in thirty-four autopsy cases of malignant tumors following radiation therapy to a portion of the heart

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, S; Yamamoto, M; Kawaguchi, Y; Shirasawa, K; Toyoda, H [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    1977-12-01

    Morphological features of the heart were studied on 34 autopsy cases of malignant tumors treated with x-ray or telecobalt irradiation to the cardiac region. Clinically, 8 cases among 11 with abnormal electrocardiograms had sinus tachycardia. On chest x-ray film, an extension of the median shadow was found in 5 among 26 cases with pericarditis. Histologically, the irradiated heart showed sinus-like capillary dilation in the myocardium and had features of pancarditis; pericarditis fibrinosa, interstitial edema between muscle fibers, myolysis or necrosis, and endocardial edema with slight inflammatory cell infiltration. Radiation pericarditis most often occurred in the case of esophageal carcinoma. Those changes throughout the cardiac wall seem to be directly induced by radiation in addition to circulatory disturbances. Electron-microscopically, there were interesting changes in the mitochondria of cardiac muscles; proliferation and aggregation, fusion of the unit membrane, and an appearance of giant mitochondria up to 3.8 ..mu.. in diameter. In the frequency and extent of both glycoprotein degeneration and myocardial fibrosis, there were no differences between 34 examined and 22 control cases. Fibrosis in the irradiated heart, however, tended to occur in the myocardium just beneath the radiation pericarditis, should be taken into consideration especially in radiotherapeutic cases of esophageal carcinoma.

  9. Calculation of lung-heart ratios for single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Soares, E.J.; King, M.A.; Glick, S.J.; Villegas, B.J.

    1996-01-01

    The authors investigate the effectiveness of simple iterative reconstruction techniques in calculating lung-heart activity ratios (LHRs). The LHR has been shown to be an effective indicator of the severity of coronary artery disease in cardiac SPECT. A study was conducted with a mathematical cardiac torso phantom that modelled uptake of 201 Tl in the heart and lung regions. The projection data included only the effects of nonuniform photon attenuation. The data were first reconstructed with zeroth-order Chang and a variant of the Bellini method, both of which utilize information from the nonuniform attenuation map. This nonuniform (NU) Bellini method compensates exactly for attenuation in the heart region, but is incorrect for other regions in the medium. These reconstructions were then used as the initial estimates in the iterative Chang, variable step-size (VSS) Chang, and Morozumi methods,m for one and five iterations. The average heart count (AHC) and average lung count (ALC) were calculated using region-of-interest (ROI) templates derived from the true activity map. The population mean LHR was tabulated as the ratio of the ALC to AHC. Using the same reconstruction procedure, the authors also calculated the sample mean LHR and standard deviation from 21 noisy 3D reconstructions

  10. Comparative Structural and functional changes in the heart and aorta of retire active and non- active endurance and bodybuilder athletes

    Directory of Open Access Journals (Sweden)

    Eskandar Rahimi

    2016-06-01

    We concluded that the BA had a greater thickness of LV posterior wall than EI and also they had a significant difference in aortic wall elasticity than BI and EI. This may be due to the Valsalva maneuver or differences in breathing of bodybuilder. We also found that the structure changes of heart in spite of detraining remain for years. Keywords: former endurance athletes, former bodybuilder athletes, Aortic elasticity, cardiac structure and function

  11. Application of the electrodiffusion method for near-wall flow diagnostics

    Directory of Open Access Journals (Sweden)

    Tihon J.

    2014-03-01

    Full Text Available The electrodiffusion method is presented as a measuring technique suitable for the flow measurement done in close proximity of the wall, thus in the region difficultly accessible by standard anemometric techniques (e.g. PIV, LDA. The experimental results obtained in different flow configurations (backward-facing step flow, wavy film flow, turbulent channel flow, rising Taylor bubbles document application capabilities of this technique, e.g. for mapping of wall shear stresses, delimitation of stable flow-recirculation zones, detection of short-time reversal of the near-wall flow, investigation of the near-wall turbulence, or detection of moving fluid particles. A new technology of sensor fabrication based on photolithography is introduced and possible applications of microsensors in microfluidic devices discussed.

  12. Regional ventricular performance and exercise training in children and young adults after repair of tetralogy of Fallot: randomized controlled pilot study.

    Science.gov (United States)

    Duppen, Nienke; Geerdink, Lianne M; Kuipers, Irene M; Bossers, Sjoerd S M; Koopman, Laurens P; van Dijk, Arie P J; Roos-Hesselink, Jolien W; De Korte, Chris L; Helbing, Willem A; Kapusta, Livia

    2015-04-01

    Public-health guidelines recommend patients with congenital heart disease to exercise. Studies have shown that patients with congenital heart disease can improve physical exercise capacity. The effect of training on regional ventricular performance has hardly been studied. We performed a pilot study to assess whether an exercise training program would result in adverse changes of regional ventricular performance in patients with corrected tetralogy of Fallot. Multicenter prospective randomized controlled pilot study in patients with tetralogy of Fallot aged 10 to 25 years. A 12-week standardized aerobic dynamic exercise training program (3 one-hour sessions per week) was used. Pre- and post-training cardiopulmonary exercise tests, MRI, and echocardiography, including tissue-Doppler imaging, were performed. Patients were randomized to the exercise group (n=28) or control group (n=20). One patient in the exercise group dropped out. Change in tissue-Doppler imaging parameters was similar in the exercise group and control group (change in right ventricle free wall peak velocity E' exercise group, 0.8±2.6 cm/s; control group, 0.9±4.1; peak velocity A' exercise group, 0.4±2.4 m/s; control group 4.6±18.1 cm/s). This randomized controlled pilot study provides preliminary data suggesting that regional ventricular performance is well maintained during 3-month aerobic dynamic exercise training in children and young adults with repaired tetralogy of Fallot. This information might help patients adhere to current public-health guidelines. URL: http//:www.trialregister.nl. Unique identifier: NTR2731. © 2015 American Heart Association, Inc.

  13. The clinical meaning of gastric-wall hyperactivity observed on sestamibi cardiac single-photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Cote, C.; Dumont, M. [Centre Hospitalier Universitaire de Quebec, Dept. of Nuclear Medicine, Quebec, Quebec (Canada)]. E-mail: christian.cote@chuq.qc.ca

    2004-06-01

    To evaluate prospectively the incidence and clinical meaning, if any, of gastric-wall hyperactivity observed on sestamibi cardiac single-photon emission computed tomography (SPECT). This phenomenon is completely different from the well-known intraluminal gastric reflux of sestamibi. A group of 819 patients who underwent sestamibi cardiac SPECT was studied from January 2000 to October 2000. Gastric-wall activity was graded qualitatively. Only patients with gastric-wall activity near or equivalent to their heart activity were considered for subsequent analysis. The medical records of patient candidates were reviewed, and their family physicians were asked to respond to a questionnaire by telephone when further information was needed. We identified 13 patients with significant gastric-wall hyperactivity, which was more intense on rest images. Our review of the clinical data shows that all these patients were suffering from dyspepsia and were taking gastric medication. These 13 cases were assigned to 3 groups: gastroesophageal reflux, chronic functional dyspepsia and nonspecific gastritis. Significant gastric-wall hyperactivity is an infrequent observation on sestamibi cardiac SPECT. Our results indicate that the presence of significant gastric-wall hyperactivity is associated with dyspepsia. It is important to realize that this gastric-wall hyperactivity by its proximity to the inferior myocardial wall could in some circumstances lead to either false-negative or false-positive findings, representing a diagnostic problem. Although infrequent, this situation could be avoided by proper quality control, including a systematic review of the raw cine data before reading the images. (author)

  14. Effects of Liquid Transpiration Cooling on Heat Transfer to the Diverging Region of a Porous-Walled Nozzle

    National Research Council Canada - National Science Library

    Schieb, Daniel

    1997-01-01

    This research effort investigated the effects of evaporation of water on the heat transferred to the wall of the diverging portion of a porous walled nozzle The AFIT High Pressure Shock Tube was used...

  15. ChIP-seq Identification of Weakly Conserved Heart Enhancers

    Energy Technology Data Exchange (ETDEWEB)

    Blow, Matthew J.; McCulley, David J.; Li, Zirong; Zhang, Tao; Akiyama, Jennifer A.; Holt, Amy; Plajzer-Frick, Ingrid; Shoukry, Malak; Wright, Crystal; Chen, Feng; Afzal, Veena; Bristow, James; Ren, Bing; Black, Brian L.; Rubin, Edward M.; Visel, Axel; Pennacchio, Len A.

    2010-07-01

    Accurate control of tissue-specific gene expression plays a pivotal role in heart development, but few cardiac transcriptional enhancers have thus far been identified. Extreme non-coding sequence conservation successfully predicts enhancers active in many tissues, but fails to identify substantial numbers of heart enhancers. Here we used ChIP-seq with the enhancer-associated protein p300 from mouse embryonic day 11.5 heart tissue to identify over three thousand candidate heart enhancers genome-wide. Compared to other tissues studied at this time-point, most candidate heart enhancers are less deeply conserved in vertebrate evolution. Nevertheless, the testing of 130 candidate regions in a transgenic mouse assay revealed that most of them reproducibly function as enhancers active in the heart, irrespective of their degree of evolutionary constraint. These results provide evidence for a large population of poorly conserved heart enhancers and suggest that the evolutionary constraint of embryonic enhancers can vary depending on tissue type.

  16. The World Society for Pediatric and Congenital Heart Surgery: its mission and history.

    Science.gov (United States)

    Tchervenkov, Christo I; Stellin, Giovanni; Kurosawa, Hiromi; Jacobs, Jeffrey P; Mavroudis, Constantine; Bernier, Pierre-Luc; Maruszewski, Bohdan; Kreutzer, Christian; Cicek, Sertac; Kinsley, Robin H; Nunn, Graham R; Jonas, Richard A

    2009-01-01

    The World Society for Pediatric and Congenital Heart Surgery (WSPCHS) was established in 2006 to assemble pediatric and congenital heart surgeons from all continents and regions of the world and their colleagues from related specialties dealing with pediatric and congenital heart disease. Since its birth, it has held a highly successful inaugural scientific meeting in 2007 in Washington, DC, and a World Summit on Pediatric and Congenital Heart Surgery Services, Education, and Cardiac Care for Children and Adults with Congenital Heart Disease in 2008 in Montreal. It currently has 549 members from 71 countries and in a short period of time has become the largest organization in the world of pediatric and congenital heart surgeons. Its brief history already seems to be a guarantee of a promising future. Projects in the areas of research, training and education, patient care, and community service will allow the Society to reach its goals. By bringing together professionals from every region of the world, the WSPCHS should play a significant role in the improvement of care for children and adults with congenital heart disease around the world.

  17. An approach for extracting the vein and heart boundaries from raw NM images

    International Nuclear Information System (INIS)

    Mitrovski, Cvetko D.; Kostov, Mitko B.

    2003-01-01

    In this paper we present our approach on prE.processing chest region dynamical NM images which enables anatomical data extraction of the vena cava and the heart. The aim of the method is developing sophisticated diagnostic software that could automatically offer the optimal positions and the shapes of the regions of interest needed for the heart studies. (Author)

  18. Decreasing Compensatory Ability of Concentric Ventricular Hypertrophy in Aortic-Banded Rat Hearts

    Directory of Open Access Journals (Sweden)

    Alexandre Lewalle

    2018-02-01

    Full Text Available The cardiac system compensates for variations in physiological and pathophysiological conditions through a dynamic remodeling at the organ, tissue, and intracellular levels in order to maintain function. However, on longer time scales following the onset of ventricular pressure overload, such remodeling may begin to inhibit physiological function and ultimately lead to heart failure. This progression from compensatory to decompensatory behavior is poorly understood, in particular owing to the absence of a unified perspective of the concomitantly remodeling subsystems. To address this issue, the present study investigates the evolution of compensatory mechanisms, in response to overload, by integrating diffusion-tensor MRI, echocardiography, and intracellular and hemodynamic measurements within consistent computational simulations of aortic-banded rat hearts. This approach allows a comparison of the relative leverage of different cardiac properties (geometry, passive mechanical stiffness, fiber configuration, diastolic and peak calcium concentrations, calcium-binding affinity, and aortic impedance to affect cardiac contraction. Measurements indicate that, following aortic banding, an ejection fraction (EF of 75% was maintained, relative to control rats, despite significant remodeling of the left-ventricular wall thickness (increasing by ~90% over 4 weeks. Applying our framework, we identified the left-ventricular wall thickness (concentric hypertrophy and the intracellular calcium dynamics as playing the dominant roles in preserving EF acutely, whereas the significance of hypertrophy decreased subsequently. This trend suggests an increasing reliance on intracellular mechanisms (average increase ~50%, rather than on anatomical features (average decrease ~60%, to achieve compensation of pump function in the early phase of heart failure.

  19. Epidemiology of childhood heart failure in Port Harcourt, Nigeria ...

    African Journals Online (AJOL)

    Background: Heart failure (HF) is a clinical syndrome that complicates a variety of childhood illnesses. Recent studies in various parts of Nigeria show a prevalence rate of 5.8-15.5%. There is relatively scant data on heart failure in children in the south-south geo-political region of the country, necessitating this study. Aim: To ...

  20. Modification of a Volume-Overload Heart Failure Model to Track Myocardial Remodeling and Device-Related Reverse Remodeling

    Science.gov (United States)

    Tuzun, Egemen; Bick, Roger; Kadipasaoglu, Cihan; Conger, Jeffrey L.; Poindexter, Brian J.; Gregoric, Igor D.; Frazier, O. H.; Towbin, Jeffrey A.; Radovancevic, Branislav

    2011-01-01

    Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods. We induced volume-overload heart failure in 2 sheep; 20 weeks later, we implanted an LVAD and assessed recovery 11 weeks thereafter. We examined changes in histologic and hemodynamic data and levels of cellular markers of CHF. Results. After CHF induction, we found increases in LV end-diastolic pressure, LV systolic and diastolic dimensions, wall thickness, left atrial diameter, and atrial natriuretic protein (ANP) and endothelin-1 (ET-1) levels; β-adrenergic receptor (BAR) and dystrophin expression decreased markedly. Biopsies confirmed LV remodeling. After LVAD support, LV systolic and diastolic dimensions, wall thickness, and mass, and ANP and ET-1 levels decreased. Histopathologic and hemodynamic markers improved, and BAR and dystrophin expression normalized. Conclusions. We describe a successful sheep model for ventricular and reverse remodeling. PMID:22347659

  1. Digital subtraction ventriculography for assessment of global and regional leftventricular parameters in comparison to conventional contrast ventriculography

    International Nuclear Information System (INIS)

    Eichstaedt, H.; Langer, M.; Felix, R.

    1984-01-01

    Since May 1982 we studied more than 100 patients with heart diseases by means of digital angiography, out of them 46 patients with a history of transmural myocardial infarction were selected. Urografin 76, 30 ml, was administered at a flow rate of 18 ml/s by means of a catheter in the superior vena cava during digital subtraction ventriculography. Results were compared with conventional contrast ventriculograms. The correlation coefficient was r=0.93 (p 0.001) for determination of ejection fraction with both methods. The data in individual cases suggest that DSV is more sensitive than conventional contrast ventriculography in determination of severely reduced ejection fractions. The methods are practically identical in qualitative evaluation of disorders of regional wall motion in the anterolateral region, while DSV is more sensitive than conventional ventriculography in evaluating the apical region. Sensitivity was 85.7% when the two methods were compared in evaluation of the inferior region of the left ventricle. Both methods are identical in demonstration of severely deformed ventricles. Digital subtraction ventriculography may replace conventional contrast ventriculography in some of situations discussed above. (orig.)

  2. Stability of ideal and resistive modes in cylindrical plasmas with resistive walls and plasma rotation

    International Nuclear Information System (INIS)

    Bondeson, A.; Xie, H.X.

    1996-01-01

    The stabilization of cylindrical plasmas by resistive walls combined with plasma rotation is analyzed. Perturbations with a single mode rational surface q=m/n in a finitely conducting plasma are treated by the resistive kink dispersion relation of Coppi. The possibilities for stabilization of ideal and resistive instabilities are explored systematically in different regions of parameter space. The study confirms that an ideal instability can be stabilized by a close-fitting wall and a rotation velocity of the order of resistive growth rate. However, the region in parameter space where such stabilization occurs is very small and appears to be difficult to exploit in experiments. The overall conclusion from the cylindrical plasma model is that resistive modes can readily be wall stabilized, whereas complete wall stabilization is hard to achieve for plasmas that are ideally unstable with the wall at infinity. 26 refs, 5 figs

  3. Domain wall oscillation in magnetic nanowire with a geometrically confined region

    Science.gov (United States)

    Sbiaa, R.; Bahri, M. Al; Piramanayagam, S. N.

    2018-06-01

    In conventional magnetic devices such as magnetic tunnel junctions, a steady oscillation of a soft layer magnetization could find its application in various electronic systems. However, these devices suffer from their low output signal and large spectral linewidth. A more elegant scheme based on domain wall oscillation could be a solution to these issues if DW dynamics could be controlled precisely in space and time. In fact, in DW devices, the magnetic configuration of domain wall and its position are strongly dependent on the device geometry and material properties. Here we show that in a constricted device with judiciously adjusted dimensions, a DW can be trapped within the central part and keep oscillating with a single frequency f. For 200 nm by 40 nm nanowire, f was found to vary from 2 GHz to 3 GHz for a current density between 4.8 × 1012 A/m2 and 5.6 × 1012 A/m2. More interestingly, the device fabrication is simply based on two long nanowires connected by adjusting the offset in both x and y directions. This new type of devices enables the conversion of dc-current to an ac-voltage in a controllable manner opening thus the possibility of a new nano-oscillators with better performance.

  4. Prevalence and clinical characteristics of mental stress-induced myocardial ischemia in patients with coronary heart disease.

    Science.gov (United States)

    Jiang, Wei; Samad, Zainab; Boyle, Stephen; Becker, Richard C; Williams, Redford; Kuhn, Cynthia; Ortel, Thomas L; Rogers, Joseph; Kuchibhatla, Maragatha; O'Connor, Christopher; Velazquez, Eric J

    2013-02-19

    The goal of this study was to evaluate the prevalence and clinical characteristics of mental stress-induced myocardial ischemia. Mental stress-induced myocardial ischemia is prevalent and a risk factor for poor prognosis in patients with coronary heart disease, but past studies mainly studied patients with exercise-induced myocardial ischemia. Eligible patients with clinically stable coronary heart disease, regardless of exercise stress testing status, underwent a battery of 3 mental stress tests followed by a treadmill test. Stress-induced ischemia, assessed by echocardiography and electrocardiography, was defined as: 1) development or worsening of regional wall motion abnormality; 2) left ventricular ejection fraction reduction ≥ 8%; and/or 3) horizontal or downsloping ST-segment depression ≥ 1 mm in 2 or more leads lasting for ≥ 3 consecutive beats during at least 1 mental test or during the exercise test. Mental stress-induced ischemia occurred in 43.45%, whereas exercise-induced ischemia occurred in 33.79% (p = 0.002) of the study population (N = 310). Women (odds ratio [OR]: 1.88), patients who were not married (OR: 1.99), and patients who lived alone (OR: 2.24) were more likely to have mental stress-induced ischemia (all p mental stress-induced ischemia (all p Mental stress-induced ischemia is more common than exercise-induced ischemia in patients with clinically stable coronary heart disease. Women, unmarried men, and individuals living alone are at higher risk for mental stress-induced ischemia. (Responses of Myocardial Ischemia to Escitalopram Treatment [REMIT]; NCT00574847). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  5. A nested-LES wall-modeling approach for computation of high Reynolds number equilibrium and non-equilibrium wall-bounded turbulent flows

    Science.gov (United States)

    Tang, Yifeng; Akhavan, Rayhaneh

    2014-11-01

    A nested-LES wall-modeling approach for high Reynolds number, wall-bounded turbulence is presented. In this approach, a coarse-grained LES is performed in the full-domain, along with a nested, fine-resolution LES in a minimal flow unit. The coupling between the two domains is achieved by renormalizing the instantaneous LES velocity fields to match the profiles of kinetic energies of components of the mean velocity and velocity fluctuations in both domains to those of the minimal flow unit in the near-wall region, and to those of the full-domain in the outer region. The method is of fixed computational cost, independent of Reτ , in homogenous flows, and is O (Reτ) in strongly non-homogenous flows. The method has been applied to equilibrium turbulent channel flows at 1000 shear-driven, 3D turbulent channel flow at Reτ ~ 2000 . In equilibrium channel flow, the friction coefficient and the one-point turbulence statistics are predicted in agreement with Dean's correlation and available DNS and experimental data. In shear-driven, 3D channel flow, the evolution of turbulence statistics is predicted in agreement with experimental data of Driver & Hebbar (1991) in shear-driven, 3D boundary layer flow.

  6. Simulating secondary organic aerosol in a regional air quality model using the statistical oxidation model – Part 2: Assessing the influence of vapor wall losses

    Directory of Open Access Journals (Sweden)

    C. D. Cappa

    2016-03-01

    Full Text Available The influence of losses of organic vapors to chamber walls during secondary organic aerosol (SOA formation experiments has recently been established. Here, the influence of such losses on simulated ambient SOA concentrations and properties is assessed in the University of California at Davis / California Institute of Technology (UCD/CIT regional air quality model using the statistical oxidation model (SOM for SOA. The SOM was fit to laboratory chamber data both with and without accounting for vapor wall losses following the approach of Zhang et al. (2014. Two vapor wall-loss scenarios are considered when fitting of SOM to chamber data to determine best-fit SOM parameters, one with “low” and one with “high” vapor wall-loss rates to approximately account for the current range of uncertainty in this process. Simulations were run using these different parameterizations (scenarios for both the southern California/South Coast Air Basin (SoCAB and the eastern United States (US. Accounting for vapor wall losses leads to substantial increases in the simulated SOA concentrations from volatile organic compounds (VOCs in both domains, by factors of  ∼  2–5 for the low and  ∼  5–10 for the high scenarios. The magnitude of the increase scales approximately inversely with the absolute SOA concentration of the no loss scenario. In SoCAB, the predicted SOA fraction of total organic aerosol (OA increases from  ∼  0.2 (no to  ∼  0.5 (low and to  ∼  0.7 (high, with the high vapor wall-loss simulations providing best general agreement with observations. In the eastern US, the SOA fraction is large in all cases but increases further when vapor wall losses are accounted for. The total OA ∕ ΔCO ratio captures the influence of dilution on SOA concentrations. The simulated OA ∕ ΔCO in SoCAB (specifically, at Riverside, CA is found to increase substantially during the day only for the high vapor wall

  7. Building America Case Study: Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation, Cold Climate Region

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    High-R wall assemblies (R-40 and above) are gaining popularity in the market due to programs like the DOE's Zero Energy Ready Home program, Passive House (PH), Net Zero Energy Home (NZEH) challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used 'double wall' systems to more practically achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double wall systems is that there are very few new exterior details. Exterior sheathing, structural bracing, house wrap or building paper, window and door flashing, and siding attachment are usually identical to good details in conventional framed wall systems. The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and result in a reduction of material brought to landfills due to failures and resulting decay. While this document focuses on double wall framing techniques, the majority of the information on how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture related damage and are intended for builders, framing contractors, architects, and consultants involved in designing and building super insulated homes.

  8. Chest wall invasion by bronchogenic carcinoma. Evaluation with Cine-MRI

    International Nuclear Information System (INIS)

    Nawano, Shigeru; Murakami, Kohji; Ohnuma, Hiroshi; Iwata, Ryoko; Hayashi, Takayuki; Moriyama, Noriyuki; Nishiwaki, Yutaka; Nagai, Kanji

    1996-01-01

    With the view of examining possible chest wall invasion of bronchogenic carcinoma, Cine-MRI was performed on 22 such cases. These cases were suspected of having above chest wall invasion by CT and their histopathological findings were obtained in surgery. The judgment of the chest wall invasion by Cine-CT was made such that non-moving up and down of the tumor with respiration involves its invasion, moving of the tumor without any up-and-down movement suspects its invasion and moving up and down of the tumor with respiration involves no invasion. The chest wall invasion was observed in 5 of 7 cases of invasion judged by Cine-MRI. For 2 false-positive cases, the histopathological findings presumed that tumor cells disappeared from the chest wall invaded region as the result of preoperative chemotherapy. The above invasion was observed in 1 of 4 cases suspected of possible invasion. Correct diagnosis was formed of 11 cases judged invasion-free by Cine-MRI. The above results suggested Cine-MRI to be useful for diagnosis of chest wall invasion of bronchogenic carcinoma. (author)

  9. LES of turbulent flow in a concentric annulus with rotating outer wall

    International Nuclear Information System (INIS)

    Hadžiabdić, M.; Hanjalić, K.; Mullyadzhanov, R.

    2013-01-01

    Highlights: • High rotation up to N = 2 dampens progressively the turbulence near the rotating outer wall. • At 2 2.8, while tending to laminarize, the flow exhibits distinct Taylor-Couette vortical rolls. -- Abstract: Fully-developed turbulent flow in a concentric annulus, r 1 /r 2 = 0.5, Re h = 12,500, with the outer wall rotating at a range of rotation rates N = U θ,wall /U b from 0.5 up to 4 is studied by large-eddy simulations. The focus is on the effects of moderate to very high rotation rates on the mean flow, turbulence statistics and eddy structure. For N up to ∼2, an increase in the rotation rate dampens progressively the turbulence near the rotating outer wall, while affecting only mildly the inner-wall region. At higher rotation rates this trend is reversed: for N = 2.8 close to the inner wall turbulence is dramatically reduced while the outer wall region remains turbulent with discernible helical vortices as the dominant turbulent structure. The turbulence parameters and eddy structures differ significantly for N = 2 and 2.8. This switch is attributed to the centrifuged turbulence (generated near the inner wall) prevailing over the axial inertial force as well as over the counteracting laminarizing effects of the rotating outer wall. At still higher rotation, N = 4, the flow gets laminarized but with distinct spiralling vortices akin to the Taylor–Couette rolls found between the two counter-rotating cylinders without axial flow, which is the limiting case when N approaches to infinity. The ratio of the centrifugal to axial inertial forces, Ta/Re 2 ∝ N 2 (where Ta is the Taylor number) is considered as a possible criterion for defining the conditions for the above regime change

  10. Wind tunnels with adapted walls for reducing wall interference

    Science.gov (United States)

    Ganzer, U.

    1979-01-01

    The basic principle of adaptable wind tunnel walls is explained. First results of an investigation carried out at the Aero-Space Institute of Berlin Technical University are presented for two dimensional flexible walls and a NACA 0012 airfoil. With five examples exhibiting very different flow conditions it is demonstrated that it is possible to reduce wall interference and to avoid blockage at transonic speeds by wall adaptation.

  11. Embryonic stem cell therapy of heart failure in genetic cardiomyopathy.

    Science.gov (United States)

    Yamada, Satsuki; Nelson, Timothy J; Crespo-Diaz, Ruben J; Perez-Terzic, Carmen; Liu, Xiao-Ke; Miki, Takashi; Seino, Susumu; Behfar, Atta; Terzic, Andre

    2008-10-01

    Pathogenic causes underlying nonischemic cardiomyopathies are increasingly being resolved, yet repair therapies for these commonly heritable forms of heart failure are lacking. A case in point is human dilated cardiomyopathy 10 (CMD10; Online Mendelian Inheritance in Man #608569), a progressive organ dysfunction syndrome refractory to conventional therapies and linked to mutations in cardiac ATP-sensitive K(+) (K(ATP)) channel subunits. Embryonic stem cell therapy demonstrates benefit in ischemic heart disease, but the reparative capacity of this allogeneic regenerative cell source has not been tested in inherited cardiomyopathy. Here, in a Kir6.2-knockout model lacking functional K(ATP) channels, we recapitulated under the imposed stress of pressure overload the gene-environment substrate of CMD10. Salient features of the human malignant heart failure phenotype were reproduced, including compromised contractility, ventricular dilatation, and poor survival. Embryonic stem cells were delivered through the epicardial route into the left ventricular wall of cardiomyopathic stressed Kir6.2-null mutants. At 1 month of therapy, transplantation of 200,000 cells per heart achieved teratoma-free reversal of systolic dysfunction and electrical synchronization and halted maladaptive remodeling, thereby preventing end-stage organ failure. Tracked using the lacZ reporter transgene, stem cells engrafted into host heart. Beyond formation of cardiac tissue positive for Kir6.2, transplantation induced cell cycle activation and halved fibrotic zones, normalizing sarcomeric and gap junction organization within remuscularized hearts. Improved systemic function induced by stem cell therapy translated into increased stamina, absence of anasarca, and benefit to overall survivorship. Embryonic stem cells thus achieve functional repair in nonischemic genetic cardiomyopathy, expanding indications to the therapy of heritable heart failure. Disclosure of potential conflicts of interest is

  12. Preattentive processing of heart cues and the perception of heart symptoms in congenital heart disease.

    Science.gov (United States)

    Karsdorp, Petra A; Kindt, Merel; Everaerd, Walter; Mulder, Barbara J M

    2007-08-01

    The present study was aimed at clarifying whether preattentive processing of heart cues results in biased perception of heart sensations in patients with congenital heart disease (ConHD) who are also highly trait anxious. Twenty-six patients with ConHD and 22 healthy participants categorized heart-related (heart rate) or neutral sensations (constant vibration) as either heart or neutral. Both sensations were evoked using a bass speaker that was attached on the chest of the participant. Before each physical sensation, a subliminal heart-related or neutral prime was presented. Biased perception of heart-sensations would become evident by a delayed categorization of the heart-related sensations. In line with the prediction, a combination of high trait anxiety and ConHD resulted in slower responses after a heart-related sensation that was preceded by a subliminal heart cue. Preattentive processing of harmless heart cues may easily elicit overperception of heart symptoms in highly trait anxious patients with ConHD.

  13. Myocardial 99mTc-sestamibi extraction and washout in hypertensive heart failure using an isolated rat heart

    International Nuclear Information System (INIS)

    Fukushima, Kenji; Momose, Mitsuru; Kondo, Chisato; Higuchi, Takahiro; Kusakabe, Kiyoko; Hagiwara, Nobuhisa

    2010-01-01

    Purpose: Myocardial mitochondria are the primary part of energy production for healthy cardiac contraction. And mitochondrial dysfunction would play an important role in progressive heart failure. In the recent years, myocardial washout of 99m Tc-sestamibi [( 99m Tc-hexakis-2-methoxy-2-methylpropyl isonitrile (MIBI)] has been introduced to be a potential marker in patients with heart failure. The objective of this study was to clarify MIBI extraction and washout kinetics using isolated perfusion system in hypertension induced model of myocardial dysfunction. Methods: Six-week-old Dahl-salt sensitive rats, allotted to 4 groups; a 5-week high-salt group (5wk-HS), 12-week high-salt group (12wk-HS) and two age-matched, low-salt diet control groups (5wk-LS and 12wk-LS). The rats in 5wk-HS and 12wk-HS groups were fed a high-salt diet (containing 8% NaCl). Cardiac function was examined by echocardiography before removing heart. Hearts were perfused according to the Langendorff method at a constant flow rate, in which 20-min MIBI washin was conducted followed by 25-min MIBI washout. Whole heart radioactivity was collected every sec by an external gamma detector. The myocardial extraction, K 1 (ml/min) and washout rate, k 2 (min -1 ) were generated. Results: High-salt diet groups showed significant high-blood pressure. Echocardiography revealed thickened LV walls in 5wk-HS, and reduced cardiac function in 12wk-HS, compared to each age-matched control group. K 1 showed no significant difference among all groups (5wk-HS: 2.36±1.07, 5wk-control: 2.59±0.28, 12wk-HS: 1.91±0.90, and 12wk-control: 2.84±0.57). k 2 in 5wk-HS was comparable to that in the age matched control group (0.00030±0.00039 vs -0.000010±0.00044), but it was increased remarkably in 18wk-HS compared to the age matched control group (0.0025±0.0011 vs 0.000025±0.000041, P<.01), and 5wk-HS (P<.01). Conclusion: In the course of hypertensive heart disease, MIBI washout was increased in the transitional state

  14. Inverse measurement of wall pressure field in flexible-wall wind tunnels using global wall deformation data

    Science.gov (United States)

    Brown, Kenneth; Brown, Julian; Patil, Mayuresh; Devenport, William

    2018-02-01

    The Kevlar-wall anechoic wind tunnel offers great value to the aeroacoustics research community, affording the capability to make simultaneous aeroacoustic and aerodynamic measurements. While the aeroacoustic potential of the Kevlar-wall test section is already being leveraged, the aerodynamic capability of these test sections is still to be fully realized. The flexibility of the Kevlar walls suggests the possibility that the internal test section flow may be characterized by precisely measuring small deflections of the flexible walls. Treating the Kevlar fabric walls as tensioned membranes with known pre-tension and material properties, an inverse stress problem arises where the pressure distribution over the wall is sought as a function of the measured wall deflection. Experimental wall deformations produced by the wind loading of an airfoil model are measured using digital image correlation and subsequently projected onto polynomial basis functions which have been formulated to mitigate the impact of measurement noise based on a finite-element study. Inserting analytic derivatives of the basis functions into the equilibrium relations for a membrane, full-field pressure distributions across the Kevlar walls are computed. These inversely calculated pressures, after being validated against an independent measurement technique, can then be integrated along the length of the test section to give the sectional lift of the airfoil. Notably, these first-time results are achieved with a non-contact technique and in an anechoic environment.

  15. Evaluation of myocardial function with the 201 Thallium scintimetry in various diseases of the heart. A correlative study based on 100 patients

    Energy Technology Data Exchange (ETDEWEB)

    Buell, U; Niendorf, H P; Strauer, B E; Hast, B

    1976-08-12

    To assess the validity of the quantitative /sup 201/Tl scintimetry in various diseases of the heart (coronary heart disease with and without myocardial infarction, non-coronary cardiomyopathy, scleroderma heart disease and asymmetric septal hypertrophy with IHSS), the /sup 201/Tl myocardial uptake values for five standardized projections (a) were correlated with the grade of LAD stenosis, (b) the pattern of myocardial wall motion and (c) were compared with the /sup 201/Tl uptake values derived from normal patients. Significant reduction (c) of /sup 201/Tl myocardial uptake could in individual cases be evaluated in acute myocardial infarction (95%), in dys- and akinesia (90%), in hypokinesia (71%), in scleroderma heart disease (50%), in non-coronary cardiomyopathy (50%) as well as in normokinesia (28%) when associated with LAD stenosis. The mean values (b) of /sup 201/Tl uptake in normo- and hypokinesia significantly differed between these two groups and from those evaluated in dys- and akinesia. The latter group showed the lowest /sup 201/Tl uptake values computed which in some cases were very close to the mean mediastinal /sup 201/Tl uptake. The correlation (a) of individual /sup 201/Tl values demonstrated that /sup 201/Tl distribution in the myocardium is not only equivalent to myocardial ''perfusion'' but is corresponding with the myocardial function. In non-coronary cardiomyopathy reduced /sup 201/Tl values sometimes could not be separated from values in coronary heart disease (and myocardial infarction). A regional increase of myocardial mass as in septal hypertrophy correlated well with an augmented /sup 201/Tl uptake when referred to the /sup 201/Tl storage in the mediastinum.

  16. Evaluation of myocardial function with the 201 Thallium scintimetry in various diseases of the heart. A correlative study based on 100 patients

    Energy Technology Data Exchange (ETDEWEB)

    Buell, U.; Niendorf, H.P.; Strauer, B.E.; Hast, B.

    1976-08-12

    To assess the validity of the quantitative /sup 201/Tl scintimetry in various diseases of the heart (coronary heart disease with and without myocardial infarction, non-coronary cardiomyopathy, scleroderma heart disease and asymmetric septal hypertrophy with IHSS), the /sup 201/Tl myocardial uptake values for five standardized projections (a) were correlated with the grade of LAD stenosis, (b) the pattern of myocardial wall motion and (c) were compared with the /sup 201/Tl uptake values derived from normal patients. Significant reduction (c) of /sup 201/Tl myocardial uptake could in individual cases be evaluated in acute myocardial infarction (95%), in dys- and akinesia (90%), in hypokinesia (71%), in scleroderma heart disease (50%), in non-coronary cardiomyopathy (50%) as well as in normokinesia (28%) when associated with LAD stenosis. The mean values (b) of /sup 201/Tl uptake in normo- and hypokinesia significantly differed between these two groups and from those evaluated in dys- and akinesia. The latter group showed the lowest /sup 201/Tl uptake values computed which in some cases were very close to the mean mediastinal /sup 201/Tl uptake. The correlation (a) of individual /sup 201/Tl values demonstrated that /sup 201/Tl distribution in the myocardium is not only equivalent to myocardial ''perfusion'' but is corresponding with the myocardial function. In non-coronary cardiomyopathy reduced /sup 201/Tl values sometimes could not be separated from values in coronary heart disease (and myocardial infarction). A regional increase of myocardial mass as in septal hypertrophy correlated well with an augmented /sup 201/Tl uptake when referred to the /sup 201/Tl storage in the mediastinum.

  17. Pathophysiology of cardiac hypertrophy and heart failure: signaling pathways and novel therapeutic targets.

    Science.gov (United States)

    Tham, Yow Keat; Bernardo, Bianca C; Ooi, Jenny Y Y; Weeks, Kate L; McMullen, Julie R

    2015-09-01

    The onset of heart failure is typically preceded by cardiac hypertrophy, a response of the heart to increased workload, a cardiac insult such as a heart attack or genetic mutation. Cardiac hypertrophy is usually characterized by an increase in cardiomyocyte size and thickening of ventricular walls. Initially, such growth is an adaptive response to maintain cardiac function; however, in settings of sustained stress and as time progresses, these changes become maladaptive and the heart ultimately fails. In this review, we discuss the key features of pathological cardiac hypertrophy and the numerous mediators that have been found to be involved in the pathogenesis of cardiac hypertrophy affecting gene transcription, calcium handling, protein synthesis, metabolism, autophagy, oxidative stress and inflammation. We also discuss new mediators including signaling proteins, microRNAs, long noncoding RNAs and new findings related to the role of calcineurin and calcium-/calmodulin-dependent protein kinases. We also highlight mediators and processes which contribute to the transition from adaptive cardiac remodeling to maladaptive remodeling and heart failure. Treatment strategies for heart failure commonly include diuretics, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers and β-blockers; however, mortality rates remain high. Here, we discuss new therapeutic approaches (e.g., RNA-based therapies, dietary supplementation, small molecules) either entering clinical trials or in preclinical development. Finally, we address the challenges that remain in translating these discoveries to new and approved therapies for heart failure.

  18. Clinical evaluation of segmental wall motion by radionuclide cardioangiography in the patients with myocardial infarction

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Uehara, Toshiisa; Kozuka, Takahiro

    1980-01-01

    To detect segmental wall motion of left ventricle is useful to identify the size and location of infarcted area in coronary arteries diseases. In this study, segmental wall motion by radionuclide cardioangiography were evaluated to compare with contrast left ventriculography in fifty patients of myocardial infarction. Segmental wall motion in RAO position by first pass method, in LAO position by multi-gated method were evaluated using an Anger camera and on-line minicomputer system by following methods; ED, ES images, sequential images, edge display, regional ejection fraction and movie imaging system (MIS). The percent agreements of segmental wall motion by RI and LVG were 84% in 350 segments of 50 cases. In all segments, segments 4, 6, 7 were better agreements than other segments. For the degree of wall motion, skinesis and dyskinesis were good agreements in both methods, while hypokinesia was slightly poor agreement (62%). On the other hand, the size of infarction, that is, percent thallium defect area was good correlated with radionuclide left ventricular ejection fraction (r = -0.855 in anterior infarction, r = -0.646 in inferior infarction). From these data, wall motion was thought to be closely related with left ventricular function, therefore, regional ejection fraction in seven areas in left ventricular image was developed and compared with segmental wall motion in left ventriculogram according to the classification of A.H.A. Comittee Report. The value of regional ejection fraction is 0.29, 0.40, 0.60 in akinesis, hypokinesis and normal. In conclusion, radionuclide cardioangiography is useful in the detection of abnormal segmental wall motion as noninvasive methods. (author)

  19. Wall-attached structures of streamwise velocity fluctuations in turbulent boundary layer

    Science.gov (United States)

    Hwang, Jinyul; Sung, Hyung Jin

    2017-11-01

    The wall-attached structures of streamwise velocity fluctuations (u) are explored using direct numerical simulation data of turbulent boundary layer at Reτ = 1000 . We identify the structures of u, which are extended close to the wall. Their height (ly) ranges from the near-wall region to the edge of turbulent boundary layer. They are geometrically self-similar in a sense that the length and width of the structures are proportional to the distance from the wall. The population density of the attached structures shows that the tall attached structures (290 wall. The wall-attached structures of u identified in the present work are a proper candidate for Townsend's attached eddy hypothesis and these structures exist in the low Reynolds number turbulent boundary layer. This work was supported by the Creative Research Initiatives (No. 2017-013369) program of the National Research Foundation of Korea (MSIP) and supported by the Supercomputing Center (KISTI).

  20. Different prognostic impact of systolic function in patients with heart failure and/or acute myocardial infarction

    DEFF Research Database (Denmark)

    Thune, Jens Jakob; Carlsen, Christian; Buch, Pernille

    2005-01-01

    with either AMI or HF, a medical history and an echocardiographic assessment of left ventricular systolic function by wall motion index (WMI) were obtained. Patients were divided into four groups: AMI with or without a history of HF, and primary HF (no recent AMI) with or without a history of ischemic heart...

  1. Operation Sadbhavana: winning hearts and minds in the Ladakh Himalayan region.

    Science.gov (United States)

    Cariappa, Mudera P; Bonventre, Eugene V; Mohanti, Bikash K

    2008-08-01

    "Sadbhavana" literally means "goodwill among people." The Indian Army has evolved a military strategy of winning hearts and minds, with this being just a phase in the broader war on terror. We have focused on actions to address the border regions of Ladakh in the Himalayas. The government of India strives against difficult conditions to provide essential services (including health care) to its population in an equitable manner; in remote areas with fragile security and hamstrung provincial government systems, the Indian Army fills this role. The Army's medical units have played a pivotal role in providing comprehensive health care as a keystone of the strategy. The endeavors of the doctors in uniform have succeeded in winning over an alienated population. A total of 163 medical camps were held in 2004, with attendance of 14,050 patients seeking medical attention and 264 patients seeking dental attention; in 2005, 87 camps were conducted, with attendance totals of 7,562 and 559, respectively. The Operation Sadbhavana military strategy has paid rich dividends in the form of changes in the perspective of the denizens of the remote and exotic locales of Ladakh. Planners must carefully analyze the target audiences and the messages delivered to those audiences at the onset of such projects. Future efforts would be enhanced by attempts to quantify the effects of medical missions on the health of the population and on population attitudes toward the Indian Army and the central government.

  2. Ultrasonic measurements of chest wall thickness and realistic chest phantom for calibration of Pu lung counting facilities

    International Nuclear Information System (INIS)

    Shirotani, Takashi

    1990-01-01

    There are four important problems for the measurements of chest wall thickness using ultrasonic device: (1) selection of optimum position of transducer and the number of measured points on the chest covered with detector, (2) estimation of adipose-to-muscle ratio in the chest wall, especially for dispersed adipose like 'marbled beef', (3) determination of regression equations for the prediction of chest wall thickness, derived from groups of different body shape, i.e. corpulent and lean, and (4) estimation of effective chest wall thickness involved self-absorption layer of lung tissue, which changes with distribution of activity in the lungs. This quantity can not be measured with ultrasonic device. Realistic chest phantom was developed. The phantom contains removable model organs (lungs, liver, kidneys and heart), model trachea and artificial rib cage, and also includes chest plates that can be placed over the chest to simulate wide range adipose-to-muscle ratio in the chest wall. Various soft tissue substitutes were made of polyurethane with different concentrations of additive, and the rib cage were made of epoxy resin with calcium carbonate. The experimental data have shown that the phantom can be used as a standard phantom for the calibration. (author)

  3. DNS, LES and RANS of turbulent heat transfer in boundary layer with suddenly changing wall thermal conditions

    International Nuclear Information System (INIS)

    Hattori, Hirofumi; Yamada, Shohei; Tanaka, Masahiro; Houra, Tomoya; Nagano, Yasutaka

    2013-01-01

    Highlights: • We study the turbulent boundary layer with heat transfer by DNS. • Turbulent boundary layers with suddenly changing wall thermal conditions are observed. • The detailed turbulent statistics and structures in turbulent thermal boundary layer are discussed. • Turbulence models in LES and RANS are evaluated using DNS results. • LES and RANS are almost in good agreement with DNS results. -- Abstract: The objectives of this study are to investigate a thermal field in a turbulent boundary layer with suddenly changing wall thermal conditions by means of direct numerical simulation (DNS), and to evaluate predictions of a turbulence model in such a thermal field, in which DNS of spatially developing boundary layers with heat transfer can be conducted using the generation of turbulent inflow data as a method. In this study, two types of wall thermal condition are investigated using DNS and predicted by large eddy simulation (LES) and Reynolds-averaged Navier–Stokes equation simulation (RANS). In the first case, the velocity boundary layer only develops in the entrance of simulation, and the flat plate is heated from the halfway point, i.e., the adiabatic wall condition is adopted in the entrance, and the entrance region of thermal field in turbulence is simulated. Then, the thermal boundary layer develops along a constant temperature wall followed by adiabatic wall. In the second case, velocity and thermal boundary layers simultaneously develop, and the wall thermal condition is changed from a constant temperature to an adiabatic wall in the downstream region. DNS results clearly show the statistics and structure of turbulent heat transfer in a constant temperature wall followed by an adiabatic wall. In the first case, the entrance region of thermal field in turbulence can be also observed. Thus, both the development and the entrance regions in thermal fields can be explored, and the effects upstream of the thermal field on the adiabatic region are

  4. ELM-Induced Plasma Wall Interactions in DIII-D

    International Nuclear Information System (INIS)

    Rudakov, D.L.; Boedo, J.A.; Yu, J.H.; Brooks, N.H.; Fenstermacher, M.E.; Groth, M.; Hollmann, E.M.; Lasnier, C.J.; McLean, A.G.; Moyer, R.A.; Stangeby, P.C.; Tynan, G.R.; Wampler, W.R.; Watkins, J.G.; West, W.P.; Wong, C.C.; Zeng, L.; Bastasz, R.J.; Buchenauer, D.; Whaley, J.

    2008-01-01

    Intense transient fluxes of particles and heat to the main chamber components induced by edge localized modes (ELMs) are of serious concern for ITER. In DIII-D, plasma interaction with the outboard chamber wall is studied using Langmuir probes and optical diagnostics including a fast framing camera. Camera data shows that ELMs feature helical filamentary structures localized at the low field side of the plasma and aligned with the local magnetic field. During the nonlinear phase of an ELM, multiple filaments are ejected from the plasma edge and propagate towards the outboard wall with velocities of 0.5-0.7 km/s. When reaching the wall, filaments result in 'hot spots'--regions of local intense plasma-material interaction (PMI) where the peak incident particle and heat fluxes are up to 2 orders of magnitude higher than those between ELMs. This interaction pattern has a complicated geometry and is neither toroidally nor poloidally symmetric. In low density/collisionality H-mode discharges, PMI at the outboard wall is almost entirely due to ELMs. In high density/collisionality discharges, contributions of ELMs and inter-ELM periods to PMI at the wall are comparable. A Midplane Material Evaluation Station (MiMES) has been recently installed in order to conduct in situ measurements of erosion/redeposition at the outboard chamber wall, including those caused by ELMs

  5. The transpiration cooled first wall and blanket concept

    International Nuclear Information System (INIS)

    Barleon, Leopold; Wong, Clement

    2002-01-01

    To achieve high thermal performance at high power density the EVOLVE concept was investigated under the APEX program. The EVOLVE W-alloy first wall and blanket concept proposes to use transpiration cooling of the first wall and boiling or vaporizing lithium (Li) in the blanket zone. Critical issues of this concept are: the Magnetohydrodynamic (MHD) pressure losses of the Li circuit, the evaporation through a capillary structure and the needed superheating of the Li at the first wall and blanket zones. Application of the transpiration concept to the blanket region results in the integrated transpiration cooling concept (ITCC) with either toroidal or poloidal first wall channels. For both orientations the routing of the liquid Li and the Li vapor has been modeled and the corresponding pressure losses have been calculated by varying the width of the supplying slot and the capillary diameter. The concept works when the sum of the active and passive pumping head is higher than the total system pressure losses and when the temperature at the inner side of the first wall does not override the superheating limit of the coolant. This cooling concept has been extended to the divertor design, and the removal of a surface heat flux of up to 10 MW/m 2 appears to be possible, but this paper will focus on the transpiration cooled first wall and blanket concept assessment

  6. Flow heterogeneity following global no-flow ischemia in isolated rabbit heart

    International Nuclear Information System (INIS)

    Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; Schustz, Amy M.; Kuo, Chaincy; Huesman, Michelle K.; Huesman, Ronald H.

    2002-01-01

    The purpose of this study was to evaluate flow heterogeneity and impaired reflow during reperfusion following 60 min global no-flow ischemia in the isolated rabbit heart. Radiolabeled microspheres were used to measure relative flow in small left ventricular (LV) segments in five ischemia + reperfused hearts and in five non-ischemic controls. Although variable in the post-ischemic hearts, flow heterogeneity was increased relative to pre-ischemia for the whole LV (0.92 plus or minus 0.41 vs. 0.37 plus or minus 0.07, P < 0.05) as well as the subendocardium (Endo) and subepicardium (Epi) considered separately (endo: 1.28 plus or minus 0.74 vs. 0.30 plus or minus 0.09; epi: 0.69 plus or minus 0.22 vs. 0.38 plus or minus 0.08; P < 0.05 for both comparisons) during early reperfusion. There were also segments with abnormally reduced reflow. The number of segments with abnormally reduced reflow increased as flow heterogeneity increased. Abnormally reduced reflow indicates that regional ischemia can persist despite restoration of normal global flow. In addition, the relationship between regional and global flow is altered and venous outflow is derived from regions with continued perfusion and not the whole LV. These observations emphasize the need to quantify regional reflow during reperfusion following sustained no-flow ischemia in the isolated rabbit heart

  7. Flow heterogeneity following global no-flow ischemia in isolated rabbit heart

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Robert C.; Powers-Risius, Patricia; Reutter, Bryan W.; Schustz, Amy M.; Kuo, Chaincy; Huesman, Michelle K.; Huesman, Ronald H.

    2003-02-01

    The purpose of this study was to evaluate flow heterogeneity and impaired reflow during reperfusion following 60 min global no-flow ischemia in the isolated rabbit heart. Radiolabeled microspheres were used to measure relative flow in small left ventricular (LV) segments in five ischemia + reperfused hearts and in five non-ischemic controls. Although variable in the post-ischemic hearts, flow heterogeneity was increased relative to pre-ischemia for the whole LV (0.92 plus or minus 0.41 vs. 0.37 plus or minus 0.07, P < 0.05) as well as the subendocardium (Endo) and subepicardium (Epi) considered separately (endo: 1.28 plus or minus 0.74 vs. 0.30 plus or minus 0.09; epi: 0.69 plus or minus 0.22 vs. 0.38 plus or minus 0.08; P < 0.05 for both comparisons) during early reperfusion. There were also segments with abnormally reduced reflow. The number of segments with abnormally reduced reflow increased as flow heterogeneity increased. Abnormally reduced reflow indicates that regional ischemia can persist despite restoration of normal global flow. In addition, the relationship between regional and global flow is altered and venous outflow is derived from regions with continued perfusion and not the whole LV. These observations emphasize the need to quantify regional reflow during reperfusion following sustained no-flow ischemia in the isolated rabbit heart.

  8. Nitrendipine binding in congestive heart failure due to myocardial infarction

    International Nuclear Information System (INIS)

    Dixon, I.M.; Lee, S.L.; Dhalla, N.S.

    1990-01-01

    Depressed cardiac pump function is the hallmark of congestive heart failure, and it is suspected that decreased influx of Ca2+ into the cardiac cell is responsible for depressed contractile function. Since Ca2+ channels in the sarcolemmal membrane are considered to be an important route for the entry of Ca2+, we examined the status of Ca2+ receptors/channels in failing rat hearts after myocardial infarction of the left ventricular free wall. For this purpose, the left coronary artery was ligated and hearts were examined 4, 8, and 16 weeks later; sham-operated animals served as controls. Hemodynamic assessment revealed decreased total mechanical energy (left ventricular systolic pressure x heart rate), increased left ventricular diastolic pressure, and decreased positive and negative dP/dt in experimental animals at 4, 8, and 16 weeks. Although accumulation of ascites in the abdominal cavity was evident at 4 weeks, other clinical signs of congestive heart failure in experimental rats were evident from the presence of lung congestion and cardiac dilatation at 8 and 16 weeks after induction of myocardial infarction. The density of Ca2+ receptors/channels in crude membranes, as assessed by [3H]nitrendipine binding assay, was found to be decreased in the uninfarcted experimental left ventricle at 8 and 16 weeks; however, no change in the affinity of nitrendipine was evident. A similar depression in the specific binding of another dihydropyridine compound, [3H]PN200-110, was also evident in failing hearts. Brain and skeletal muscle crude membrane preparations, unlike those of the right ventricle and liver, revealed a decrease in Ca2+ receptors/channels density in experimental animals at 16 weeks

  9. [Topography of the contours of the inner surface of the wall of the left ventricle of the heart in systole].

    Science.gov (United States)

    Uglov, F G; Zubtsovskiĭ, V N; Bol'shakov, O P; Mursalova, F A; Tarasov, A N

    1984-09-01

    Chosen at random 38 diastolic preparations of human hearts from persons having not any cardiac pathology, as demonstrate the postmortem examination, have been investigated. The left ventricle casts have been made during the first 24 hours after death according to a strictly fixed technique by means of filling the cardiac chambers with polymere mass--protacryl--under a physiological pressure of the diastolic filling. The trabecules are arranged as a spiral from the apex of the ventricle up to the atrioventricular fibrous ring, with approaching the apex the spiral step increases and the trabecules straighten. The left ventricle cast is devided into some planes, the envelopes and the trabecularity lines are measured. Average values of the shift in the trabecularity lines I, II, III and in the cross sections B, C, D, E are defined in relation to the plane A and in every case in relation to the previous plane Cn-1. The data obtained are presented in tables and diagrams. The greatest shift demonstrate the trabecularity lines I running predominantly along the posterior wall of the left ventricle in the planes B and which are situated nearer to the atrioventricular ring projection. Owing to the presence of the spiral-shaped course of the trabecules, it is possible to suppose that it influences the blood stream twisting clockwise in the left ventricle during the diastole phase. This indicates the necessity to work out some new constructions of artificial cardiac valves, securing the twisted blood stream. The condition mentioned should be taken into consideration while making prostheses of the cardiac valves.

  10. Diagnostic evaluation of ischemic heart disease by X-ray computed tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Masuda, Yoshiaki; Kobayashi, Shiro; Takasu, Junichiro; Sakakibara, Makoto; Imai, Hitoshi; Aoyagi, Yutaka; Morooka, Nobuhiro; Watanabe, Shigeru; Inagaki, Yoshiaki

    1987-01-01

    To assess the usefulness of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in detecting and evaluating ischemic heart disease, conventional and enhanced CT were performed for 180 patients (150 with transmural infarction, 12 with subendocardial infarction, and 18 with angina pectoris). MRI examinations were performed for 38 patients (31 with transmural infarction, three with subendocardial infarction, and four with angina pectoris). With enhanced CT, two findings in the myocardium were direct evidence of myocardial infarction: 1) filling defects on the early scans, and 2) late enhancement of the myocardium on the delayed scans. The former were observed mainly at the sites of recent anterior myocardial infarction and the latter were seen in about half of the patients with recent and remote anterior myocardial infarctions. However, these findings were inadequately imaged in patients with inferoposterior infarction and subendocardial infarction. Among 137 patients with transmural infarction, enhanced CT revealed left ventricular aneurysms in 51 (37 %) and ventricular thrombi in 26 (19 %). ECG-gated MRI apparatus having a superconducting magnetic operating at 0.25 Tesla was used, and data for this study were collected using the single-slice spin echo technique. In eight of nine patients with acute myocardial infarction, gated MRI demonstrated the infarcted myocardium as regions of high signal intensity relative to that of the adjacent normal myocardium. Such a difference in MRI signal intensity was scarcely recognized in the chronic stage of myocardial infarction, but the indirect findings of infarction, such as regional wall thinning, wall motion disturbances, left ventricular aneurysms, and ventricular thrombi were easily detected using MRI. No characteristic finding was obtained by CT or MRI in patients with angina pectoris. (author)

  11. Heart transplantation in adults with congenital heart disease.

    Science.gov (United States)

    Houyel, Lucile; To-Dumortier, Ngoc-Tram; Lepers, Yannick; Petit, Jérôme; Roussin, Régine; Ly, Mohamed; Lebret, Emmanuel; Fadel, Elie; Hörer, Jürgen; Hascoët, Sébastien

    2017-05-01

    With the advances in congenital cardiac surgery and postoperative care, an increasing number of children with complex congenital heart disease now reach adulthood. There are already more adults than children living with a congenital heart defect, including patients with complex congenital heart defects. Among these adults with congenital heart disease, a significant number will develop ventricular dysfunction over time. Heart failure accounts for 26-42% of deaths in adults with congenital heart defects. Heart transplantation, or heart-lung transplantation in Eisenmenger syndrome, then becomes the ultimate therapeutic possibility for these patients. This population is deemed to be at high risk of mortality after heart transplantation, although their long-term survival is similar to that of patients transplanted for other reasons. Indeed, heart transplantation in adults with congenital heart disease is often challenging, because of several potential problems: complex cardiac and vascular anatomy, multiple previous palliative and corrective surgeries, and effects on other organs (kidney, liver, lungs) of long-standing cardiac dysfunction or cyanosis, with frequent elevation of pulmonary vascular resistance. In this review, we focus on the specific problems relating to heart and heart-lung transplantation in this population, revisit the indications/contraindications, and update the long-term outcomes. Copyright © 2017. Published by Elsevier Masson SAS.

  12. Acute myocarditis with normal wall motion detected with 2D speckle tracking echocardiography

    Directory of Open Access Journals (Sweden)

    Thomas Sturmberger

    2016-05-01

    Full Text Available We present the case of a 26-year-old male with acute tonsillitis who was referred for coronary angiography because of chest pain, elevated cardiac biomarkers, and biphasic T waves. The patient had no cardiovascular risk factors. Echocardiography showed no wall motion abnormalities and no pericardial effusion. 2D speckle tracking revealed distinct decreased regional peak longitudinal systolic strain in the lateral and posterior walls. Ischemic disease was extremely unlikely in view of his young age, negative family history regarding coronary artery disease, and lack of regional wall motion abnormalities on the conventional 2D echocardiogram. Coronary angiography was deferred as myocarditis was suspected. To confirm the diagnosis, cardiac magnetic resonance tomography (MRT was performed, showing subepicardial delayed hyperenhancement in the lateral and posterior walls correlating closely with the strain pattern obtained by 2D speckle tracking echocardiography. With a working diagnosis of acute myocarditis associated with acute tonsillitis, we prescribed antibiotics and nonsteroidal anti-inflammatory drugs. The patient’s clinical signs resolved along with normalization of serum creatine kinase (CK levels, and the patient was discharged on the third day after admission. Learning points: • Acute myocarditis can mimic acute coronary syndromes. • Conventional 2D echocardiography lacks specific features for detection of subtle regional wall motion abnormalities. • 2D speckle tracking expands the scope of echocardiography in identifying myocardial dysfunction derived from edema in acute myocarditis.

  13. The distribution of wall shear stress downstream of a change in roughness

    International Nuclear Information System (INIS)

    Loureiro, J.B.R.; Sousa, F.B.C.C.; Zotin, J.L.Z.; Silva Freire, A.P.

    2010-01-01

    In the present work, six different experimental techniques are used to characterize the non-equilibrium flow downstream of a rough-to-smooth step change in surface roughness. Over the rough surface, wall shear stress results obtained through the form drag and the Reynolds stress methods are shown to be mutually consistent. Over the smooth surface, reference wall shear stress data is obtained through two optical methods: linear velocity profiles obtained through laser-Doppler anemometry and a sensor surface, the diverging fringe Doppler sensor. The work shows that the two most commonly used methods to determine the wall shear stress, the log-law gradient method and the Reynolds shear stress method, are completely inappropriate in the developing flow region. Preston tubes, on the other hand, are shown to perform well in the region of a non-equilibrium flow.

  14. Women's Heart Disease: Heart Attack Symptoms

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Women's Heart Disease Heart Attack Symptoms Past Issues / Winter ... most common heart attack symptom in men and women is chest pain or discomfort. However, women also ...

  15. The Use of Fluid Mechanics to Predict Regions of Microscopic Thrombus Formation in Pulsatile VADs.

    Science.gov (United States)

    Topper, Stephen R; Navitsky, Michael A; Medvitz, Richard B; Paterson, Eric G; Siedlecki, Christopher A; Slattery, Margaret J; Deutsch, Steven; Rosenberg, Gerson; Manning, Keefe B

    2014-03-01

    We compare the velocity and shear obtained from particle image velocimetry (PIV) and computational fluid dynamics (CFD) in a pulsatile ventricular assist device (VAD) to further test our thrombus predictive methodology using microscopy data from an explanted VAD. To mimic physiological conditions in vitro , a mock circulatory loop is used with a blood analog that matched blood's viscoelastic behavior at 40% hematocrit. Under normal physiologic pressures and for a heart rate of 75 bpm, PIV data is acquired and wall shear maps are produced. The resolution of the PIV shear rate calculations are tested using the CFD and found to be in the same range. A bovine study, using a model of the 50 cc Penn State V-2 VAD, for 30 days at a constant beat rate of 75 beats per minute (bpm) provides the microscopic data whereby after the 30 days, the device is explanted and the sac surface analyzed using scanning electron microscopy (SEM) and, after immunofluorescent labeling for platelets and fibrin, confocal microscopy. Areas are examined based on PIV measurements and CFD, with special attention to low shear regions where platelet and fibrin deposition are most likely to occur. Data collected within the outlet port in a direction normal to the front wall of the VAD shows that some regions experience wall shear rates less than 500 s -1 , which increases the likelihood of platelet and fibrin deposition. Despite only one animal study, correlations between PIV, CFD, and in vivo data show promise. Deposition probability is quantified by the thrombus susceptibility potential, a calculation to correlate low shear and time of shear with deposition.

  16. Possibilities of exercise radionuclide ventriculography carried out in equilibrium in the detection of ischaemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Csernay, L.; Mester, J.; Edes, I.; Pavics, L.; Gruber, N.; Szasz, K.; Csanady, M.

    1985-08-04

    Authors give account of the initiation of the exercise radionuclide ventriculography and of their diagnostic experiences. In 33 control persons and 20 patients with coronary heart disease verified with coronarography, the left ventricular ejection fraction, the wall motion and the systolic and diastolic volume of the left ventricle were examined at rest and during exercise. A decrease or an increase of not more than 5% of ejection fraction, the exercise induced wall motion abnormalities or an increase of resting wall motion disorder were interpreted as an index of underlying significant coronary stenosis. A sensitivity of 90% and a specificity of 88% of the method were found. Upon the results, which are in good agreement with literary data, the initiation of the method in nuclear medical laboratories equipped with camera-computer system is proposed

  17. Possibilities of exercise radionuclide ventriculography carried out in equilibrium in the detection of ischaemic heart disease

    International Nuclear Information System (INIS)

    Csernay, Laszlo; Mester, Janos; Edes, Istvan; Pavics, Laszlo; Gruber, Noemi; Szasz, Karoly; Csanady, Miklos

    1985-01-01

    Authors give account of the initiation of the exercise radionuclide ventriculography and of their diagnostic experiences. In 33 control persons and 20 patients with coronary heart disease verified with coronarography, the left ventricular ejection fraction, the wall motion and the systolic and diastolic volume of the left ventricle were examined at rest and during exercise. A decrease or an increase of not more than 5% of ejection fraction, the exercise induced wall motion abnormalities or an increase of resting wall motion disorder were interpreted as an index of underlying significant coronary stenosis. A sensitivity of 90% and a specificity of 88% of the method were found. Upon the results, which are in good agreement with literary data, the initiation of the method in nuclear medical laboratories equipped with camera-computer system is proposed. (author)

  18. Wood Pulp Digetster Wall Corrosion Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Giles, GE

    2003-09-18

    The modeling of the flow in a wood pulp digester is but one component of the investigation of the corrosion of digesters. This report describes the development of a Near-Wall-Model (NWM) that is intended to couple with a CFD model that determines the flow, heat, and chemical species transport and reaction within the bulk flow of a digester. Lubrication theory approximations were chosen from which to develop a model that could determine the flow conditions within a thin layer near the vessel wall using information from the interior conditions provided by a CFD calculation of the complete digester. The other conditions will be determined by coupled solutions of the wood chip, heat, and chemical species transport and chemical reactions. The NWM was to couple with a digester performance code in an iterative fashion to provide more detailed information about the conditions within the NW region. Process Simulations, Ltd (PSL) is developing the digester performance code. This more detailed (and perhaps more accurate) information from the NWM was to provide an estimate of the conditions that could aggravate the corrosion at the wall. It is intended that this combined tool (NWM-PSL) could be used to understand conditions at/near the wall in order to develop methods to reduce the corrosion. However, development and testing of the NWM flow model took longer than anticipated and the other developments (energy and species transport, chemical reactions and linking with the PSL code) were not completed. The development and testing of the NWM are described in this report. In addition, the investigation of the potential effects of a clear layer (layer reduced in concentration of wood chips) near the wall is reported in Appendix D. The existence of a clear layer was found to enhance the flow near the wall.

  19. Plant-based foods containing cell wall polysaccharides rich in specific active monosaccharides protect against myocardial injury in rat myocardial infarction models.

    Science.gov (United States)

    Lim, Sun Ha; Kim, Yaesil; Yun, Ki Na; Kim, Jin Young; Jang, Jung-Hee; Han, Mee-Jung; Lee, Jongwon

    2016-12-08

    Many cohort studies have shown that consumption of diets containing a higher composition of foods derived from plants reduces mortality from coronary heart disease (CHD). Here, we examined the active components of a plant-based diet and the underlying mechanisms that reduce the risk of CHD using three rat models and a quantitative proteomics approach. In a short-term myocardial infarction (MI) model, intake of wheat extract (WE), the representative cardioprotectant identified by screening approximately 4,000 samples, reduced myocardial injury by inhibiting apoptosis, enhancing ATP production, and maintaining protein homeostasis. In long-term post-MI models, this myocardial protection resulted in ameliorating adverse left-ventricular remodelling, which is a predictor of heart failure. Among the wheat components, arabinose and xylose were identified as active components responsible for the observed efficacy of WE, which was administered via ingestion and tail-vein injections. Finally, the food components of plant-based diets that contained cell wall polysaccharides rich in arabinose, xylose, and possibly fucose were found to confer protection against myocardial injury. These results show for the first time that specific monosaccharides found in the cell wall polysaccharides in plant-based diets can act as active ingredients that reduce CHD by inhibiting postocclusion steps, including MI and heart failure.

  20. Surface compositions in the Aristarchus Region: Implications for regional stratigraphy

    Science.gov (United States)

    Hawke, H. R.; Lucey, P. G.; Mccord, T. B.; Pieters, C. M.; Head, J. W.

    1984-01-01

    Near infrared reflectance spectra for the Aristachus region, obtained using the 2.2m UH telescope at the Mauna Kea Observatory, were reduced and analyzed. The spectra obtained for the central peak, southern floor, southwestern wall, eastern wall, and northwestern wall of Aristachus crater exhibit shallow continuum slopes, relatively strong feldspar bands, pyroxene bands stronger than those typically seen in the spectra of fresh higland features, and pyroxene band centers near l micrometer suggesting the dominance of Ca rich clinopyroxene. The spectrum of the south rim of Aristachus is quite distinct from those of other crater units. The position of Aristrchus on the plateau/mare boundary raises questions concerning compositional variations in crater ejects deposits.

  1. Thermal dynamic simulation of wall for building energy efficiency under varied climate environment

    Science.gov (United States)

    Wang, Xuejin; Zhang, Yujin; Hong, Jing

    2017-08-01

    Aiming at different kind of walls in five cities of different zoning for thermal design, using thermal instantaneous response factors method, the author develops software to calculation air conditioning cooling load temperature, thermal response factors, and periodic response factors. On the basis of the data, the author gives the net work analysis about the influence of dynamic thermal of wall on air-conditioning load and thermal environment in building of different zoning for thermal design regional, and put forward the strategy how to design thermal insulation and heat preservation wall base on dynamic thermal characteristic of wall under different zoning for thermal design regional. And then provide the theory basis and the technical references for the further study on the heat preservation with the insulation are in the service of energy saving wall design. All-year thermal dynamic load simulating and energy consumption analysis for new energy-saving building is very important in building environment. This software will provide the referable scientific foundation for all-year new thermal dynamic load simulation, energy consumption analysis, building environment systems control, carrying through farther research on thermal particularity and general particularity evaluation for new energy -saving walls building. Based on which, we will not only expediently design system of building energy, but also analyze building energy consumption and carry through scientific energy management. The study will provide the referable scientific foundation for carrying through farther research on thermal particularity and general particularity evaluation for new energy saving walls building.

  2. Wall roughness effects on flow and scouring in curved channels with gravel bed

    OpenAIRE

    Hersberger, Daniel S.

    2002-01-01

    Wall roughness effects on flow and scouring in curved channels with gravel bed In the narrow valleys in Alpine regions, rivers frequently flow across constructed zones, passing through villages and cities. Due to limited space, the protection from high floods often needs to be ensured by protection walls. During floods, these protection walls may be endangered by scour phenomena, especially if they are located in bends. In the past, the potential danger of underscoured structures was reduced ...

  3. Anterior Abdominal Wall Desmoids Tumor in a Five Year Old Girl – A ...

    African Journals Online (AJOL)

    xp

    ABSTRACT: Desmoid tumors are rare, slow – growing, mesenchymal monoclinic proliferation. It may occur as intra-abdominal tumor usually affecting the mesentery of the intestine or it could be extra-abdominal in which they may affect the popliteal region, the chest wall or the anterior abdominal wall. Reports in children ...

  4. Is There a Dose-Response Relationship for Heart Disease With Low-Dose Radiation Therapy?

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eugene [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Corbett, James R. [Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Moran, Jean M. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Griffith, Kent A. [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Marsh, Robin B.; Feng, Mary; Jagsi, Reshma; Kessler, Marc L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Ficaro, Edward C. [Division of Nuclear Medicine, Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Pierce, Lori J., E-mail: ljpierce@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-03-15

    Purpose: To quantify cardiac radiation therapy (RT) exposure using sensitive measures of cardiac dysfunction; and to correlate dysfunction with heart doses, in the setting of adjuvant RT for left-sided breast cancer. Methods and Materials: On a randomized trial, 32 women with node-positive left-sided breast cancer underwent pre-RT stress single photon emission computed tomography (SPECT-CT) myocardial perfusion scans. Patients received RT to the breast/chest wall and regional lymph nodes to doses of 50 to 52.2 Gy. Repeat SPECT-CT scans were performed 1 year after RT. Perfusion defects (PD), summed stress defects scores (SSS), and ejection fractions (EF) were evaluated. Doses to the heart and coronary arteries were quantified. Results: The mean difference in pre- and post-RT PD was −0.38% ± 3.20% (P=.68), with no clinically significant defects. To assess for subclinical effects, PD were also examined using a 1.5-SD below the normal mean threshold, with a mean difference of 2.53% ± 12.57% (P=.38). The mean differences in SSS and EF before and after RT were 0.78% ± 2.50% (P=.08) and 1.75% ± 7.29% (P=.39), respectively. The average heart Dmean and D95 were 2.82 Gy (range, 1.11-6.06 Gy) and 0.90 Gy (range, 0.13-2.17 Gy), respectively. The average Dmean and D95 to the left anterior descending artery were 7.22 Gy (range, 2.58-18.05 Gy) and 3.22 Gy (range, 1.23-6.86 Gy), respectively. No correlations were found between cardiac doses and changes in PD, SSS, and EF. Conclusions: Using sensitive measures of cardiac function, no clinically significant defects were found after RT, with the average heart Dmean <5 Gy. Although a dose response may exist for measures of cardiac dysfunction at higher doses, no correlation was found in the present study for low doses delivered to cardiac structures and perfusion, SSS, or EF.

  5. The Risk of Heart Failure and Cardiometabolic Complications in Obesity May Be Masked by an Apparent Healthy Status of Normal Blood Glucose

    Directory of Open Access Journals (Sweden)

    Shuchita Tiwari

    2013-01-01

    Full Text Available Although many obese individuals are normoglycemic and asymptomatic of cardiometabolic complications, this apparent healthy state may be a misnomer. Since heart failure is a major cause of mortality in obesity, we investigated the effects of heme-oxygenase (HO on heart failure and cardiometabolic complications in obese normoglycemic Zucker-fatty rats (ZFs. Treatment with the HO-inducer, hemin, reduced markers of heart failure, such as osteopontin and osteoprotegerin, abated left-ventricular (LV hypertrophy/fibrosis, extracellular matrix/profibrotic proteins including collagen IV, fibronectin, TGF-β1, and reduced cardiac lesions. Furthermore, hemin suppressed inflammation by abating macrophage chemoattractant protein-1, macrophage-inflammatory protein-1 alpha, TNF-α, IL-6, and IL-1β but enhanced adiponectin, atrial-natriuretic peptide (ANP, HO activity, insulin sensitivity, and glucose metabolism. Correspondingly, hemin improved several hemodynamic/echocardiographic parameters including LV-diastolic wall thickness, LV-systolic wall thickness, mean-arterial pressure, arterial-systolic pressure, arterial-diastolic pressure, LV-developed pressure, +dP/dt, and cardiac output. Contrarily, the HO-inhibitor, stannous mesoporphyrin nullified the hemin effect, exacerbating inflammatory/oxidative insults and aggravated insulin resistance (HOMA-index. We conclude that perturbations in insulin signaling and cardiac function may be forerunners to overt hyperglycemia and heart failure in obesity. Importantly, hemin improves cardiac function by suppressing markers of heart failure, LV hypertrophy, cardiac lesions, extracellular matrix/profibrotic proteins, and inflammatory/oxidative mediators, while concomitantly enhancing the HO-adiponectin-ANP axis.

  6. Myocardial {sup 99m}Tc-sestamibi extraction and washout in hypertensive heart failure using an isolated rat heart

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, Kenji [Department of Cardiology, Tokyo Women' s Medical University, Tokyo 162-8666 (Japan); Department of Radiology, Johns Hopkins University, Baltimore, MD (United States); Momose, Mitsuru, E-mail: mmomose@rad.twmu.ac.j [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women' s Medical University, Tokyo 162-8666 (Japan); Kondo, Chisato [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women' s Medical University, Tokyo 162-8666 (Japan); Higuchi, Takahiro [Department of Radiology, Johns Hopkins University, Baltimore, MD (United States); Kusakabe, Kiyoko [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women' s Medical University, Tokyo 162-8666 (Japan); Hagiwara, Nobuhisa [Department of Cardiology, Tokyo Women' s Medical University, Tokyo 162-8666 (Japan)

    2010-11-15

    Purpose: Myocardial mitochondria are the primary part of energy production for healthy cardiac contraction. And mitochondrial dysfunction would play an important role in progressive heart failure. In the recent years, myocardial washout of {sup 99m}Tc-sestamibi [({sup 99m}Tc-hexakis-2-methoxy-2-methylpropyl isonitrile (MIBI)] has been introduced to be a potential marker in patients with heart failure. The objective of this study was to clarify MIBI extraction and washout kinetics using isolated perfusion system in hypertension induced model of myocardial dysfunction. Methods: Six-week-old Dahl-salt sensitive rats, allotted to 4 groups; a 5-week high-salt group (5wk-HS), 12-week high-salt group (12wk-HS) and two age-matched, low-salt diet control groups (5wk-LS and 12wk-LS). The rats in 5wk-HS and 12wk-HS groups were fed a high-salt diet (containing 8% NaCl). Cardiac function was examined by echocardiography before removing heart. Hearts were perfused according to the Langendorff method at a constant flow rate, in which 20-min MIBI washin was conducted followed by 25-min MIBI washout. Whole heart radioactivity was collected every sec by an external gamma detector. The myocardial extraction, K{sub 1} (ml/min) and washout rate, k{sub 2} (min{sup -1}) were generated. Results: High-salt diet groups showed significant high-blood pressure. Echocardiography revealed thickened LV walls in 5wk-HS, and reduced cardiac function in 12wk-HS, compared to each age-matched control group. K{sub 1} showed no significant difference among all groups (5wk-HS: 2.36{+-}1.07, 5wk-control: 2.59{+-}0.28, 12wk-HS: 1.91{+-}0.90, and 12wk-control: 2.84{+-}0.57). k{sub 2} in 5wk-HS was comparable to that in the age matched control group (0.00030{+-}0.00039 vs -0.000010{+-}0.00044), but it was increased remarkably in 18wk-HS compared to the age matched control group (0.0025{+-}0.0011 vs 0.000025{+-}0.000041, P<.01), and 5wk-HS (P<.01). Conclusion: In the course of hypertensive heart disease, MIBI

  7. Purification of a Streptococcus mutans protein that binds to heart tissue and glycosaminoglycans.

    OpenAIRE

    Choi, S H; Stinson, M W

    1989-01-01

    Proteins of Streptococcus mutans MT703 were isolated by differential filtration from chemically defined culture medium following growth of the bacteria. Incubation of this preparation with cryostat-cut sections of fresh rabbit cardiac muscle resulted in deposition of streptococcal components on basement membranes of sarcolemmal sheaths and capillary walls, as indicated by indirect immunofluorescence assay. Binding of radioiodinated streptococcal proteins to heart in vitro was time dependent a...

  8. 3-D simulation of hanging wall effect at dam site

    Science.gov (United States)

    Zhang, L.; Xu, Y.

    2017-12-01

    Hanging wall effect is one of the near fault effects. This paper focuses on the difference of the ground motions on the hanging wall side between the footwall side of the fault at dam site considering the key factors, such as actual topography, the rupture process. For this purpose, 3-D ground motions are numerically simulated by the spectrum element method (SEM), which takes into account the physical mechanism of generation and propagation of seismic waves. With the SEM model of 548 million DOFs, excitation and propagation of seismic waves are simulated to compare the difference between the ground motion on the hanging wall side and that on the footwall side. Take Dagangshan region located in China as an example, several seismogenic finite faults with different dip angle are simulated to investigate the hanging wall effect. Furthermore, by comparing the ground motions of the receiving points, the influence of several factors on hanging wall effect is investigated, such as the dip of the fault and the fault type (strike slip fault or dip-slip fault). The peak acceleration on the hanging wall side is obviously larger than those on the footwall side, which numerically evidences the hanging wall effect. Besides, the simulation shows that only when the dip is less than 70° does the hanging wall effect deserve attention.

  9. Normal and abnormal electrical activation of the heart. Imaging patterns obtained by phase analysis of equilibrium cardiac studies

    International Nuclear Information System (INIS)

    Pavel, D.; Byrom, E.; Swiryn, S.; Meyer-Pavel, C.; Rosen, K.

    1981-01-01

    By using a temporal Fourier analysis of gated equilibrium cardiac studies, phase images were obtained. These functional images were analysed qualitatively and quantitatively to determine if specific patterns can be found for normal versus abnormal electrical activation of the heart. The study included eight subjects with normal cardiac function and 24 patients with abnormal electrical activation: eight with left bundle branch block (LBBB), two with right bundle branch block (RBBB), six with Wolff-Parkinson-White syndrome (WPW), one with junctional rhythm, one with spontaneous sustained ventricular tachycardia (VT) (all with normal wall motion), two with chronic transvenous pacemakers, and four with induced sustained VT (all with regional wall motion abnormalities). The results show that the two ventricals have the same mean phase (within +-9 0 ) in normals, but significantly different mean phases in all patients with bundle branch blocks. Of the six WPW patients, three had a distinctive abnormal pattern. The patient with junctional rhythm, those with transvenous pacemakers, and those with VT all had abnormal patterns on the phase image. The phase image is capable of showing differences between patients with electrical activation and a variety of electrical abnormalities. Within the latter category distinct patterns can be associated with each type of abnormality. (author)

  10. Myocardial perfusion imaging for the detection of coronary heart disease

    International Nuclear Information System (INIS)

    Strauss, H.W.; Cook, D.J.; Bailey, I.; Rouleau, J.; Pitt, B.

    1976-01-01

    A method of myocardial perfusion imaging using 201 Tl is described. Thallium is able to substitute for potassium in biological systems including transport by the sodium--potassium ATP-ase system. The high extraction efficiency of the heart for 201 Tl offers a method whereby a tracer may be administered intravenously and is concentrated to a significant degree by the heart. However, only about 3 to 4 percent of the dose administered lodges in the myocardium. Experiments with dogs indicated that the regional distribution of Tl in the heart reflects the regional distribution of blood flow. The goal is to develop a procedure that can detect those patients with significant disease prior to the onset of a catastrophic event and studies are being undertaken to improve the sensitivity of the method for the detection of smaller lesions in the myocardium

  11. The Mid America Heart Institute: part II.

    Science.gov (United States)

    McCallister, Ben D; Steinhaus, David M

    2003-01-01

    The Mid America Heart Institute (MAHI) is one of the first and largest hospitals developed and designed specifically for cardiovascular care. The MAHI hybrid model, which is a partnership between the not-for-profit Saint Luke's Health System, an independent academic medical center, and a private practice physician group, has been extremely successful in providing high-quality patient care as well as developing strong educational and research programs. The Heart Institute has been the leader in providing cardiovascular care in the Kansas City region since its inception in 1975. Although challenges in the future are substantial, it is felt that the MAHI is in an excellent position to deal with the serious issues in health care because of the Heart Institute, its facility, organization, administration, dedicated medical and support staff, and its unique business model of physician management. In part I, the authors described the background and infrastructure of the Heart Institute. In part II, cardiovascular research and benefits of physician management are addressed.

  12. The Mid America Heart Institute: part 1.

    Science.gov (United States)

    McCallister, Ben D; Steinhaus, David M

    2003-01-01

    The Mid America Heart Institute (MAHI) is one of the first and largest hospitals developed and designed specifically for cardiovascular care. The MAHI hybrid model, which is a partnership between the not-for-profit Saint Luke's Health System, an independent academic medical center, and a private practice physician group, has been extremely successful in providing high-quality patient care as well as developing strong educational and research programs. The Heart Institute has been the leader in providing cardiovascular care in the Kansas City region since its inception in 1975. Although challenges in the future are substantial, it is felt that the MAHI is in an excellent position to deal with the serious issues in health care because of the Heart Institute, its facility, organization, administration, dedicated medical and support staff, and its unique business model of physician management. In part I, the authors describe the background and infrastructure of the Heart Institute. In part II, cardiovascular research and benefits of physician management will be addressed.

  13. Heart murmurs

    Science.gov (United States)

    Chest sounds - murmurs; Heart sounds - abnormal; Murmur - innocent; Innocent murmur; Systolic heart murmur; Diastolic heart murmur ... The heart has 4 chambers: Two upper chambers (atria) Two lower chambers (ventricles) The heart has valves that close ...

  14. On the assumption of vanishing temperature fluctuations at the wall for heat transfer modeling

    Science.gov (United States)

    Sommer, T. P.; So, R. M. C.; Zhang, H. S.

    1993-01-01

    Boundary conditions for fluctuating wall temperature are required for near-wall heat transfer modeling. However, their correct specifications for arbitrary thermal boundary conditions are not clear. The conventional approach is to assume zero fluctuating wall temperature or zero gradient for the temperature variance at the wall. These are idealized specifications and the latter condition could lead to an ill posed problem for fully-developed pipe and channel flows. In this paper, the validity and extent of the zero fluctuating wall temperature condition for heat transfer calculations is examined. The approach taken is to assume a Taylor expansion in the wall normal coordinate for the fluctuating temperature that is general enough to account for both zero and non-zero value at the wall. Turbulent conductivity is calculated from the temperature variance and its dissipation rate. Heat transfer calculations assuming both zero and non-zero fluctuating wall temperature reveal that the zero fluctuating wall temperature assumption is in general valid. The effects of non-zero fluctuating wall temperature are limited only to a very small region near the wall.

  15. Cosmic bubble and domain wall instabilities II: fracturing of colliding walls

    Energy Technology Data Exchange (ETDEWEB)

    Braden, Jonathan [CITA, University of Toronto,60 St. George Street, Toronto, ON, M5S 3H8 (Canada); Department of Physics, University of Toronto,60 St. George Street, Toronto, ON, M5S 3H8 (Canada); Department of Physics and Astronomy, University College London,Gower Street, London, WC1E 6BT (United Kingdom); Bond, J. Richard [CITA, University of Toronto,60 St. George Street, Toronto, ON, M5S 3H8 (Canada); Mersini-Houghton, Laura [Department of Physics and Astronomy, University of North Carolina-Chapel Hill,1 Phillips Hall, 120 E. Cameron Avenue, Chapel Hill, NC 27599-3255 (United States)

    2015-08-26

    We study collisions between nearly planar domain walls including the effects of small initial nonplanar fluctuations. These perturbations represent the small fluctuations that must exist in a quantum treatment of the problem. In a previous paper, we demonstrated that at the linear level a subset of these fluctuations experience parametric amplification as a result of their coupling to the planar symmetric background. Here we study the full three-dimensional nonlinear dynamics using lattice simulations, including both the early time regime when the fluctuations are well described by linear perturbation theory as well as the subsequent stage of fully nonlinear evolution. We find that the nonplanar fluctuations have a dramatic effect on the overall evolution of the system. Specifically, once these fluctuations begin to interact nonlinearly the split into a planar symmetric part of the field and the nonplanar fluctuations loses its utility. At this point the colliding domain walls dissolve, with the endpoint of this being the creation of a population of oscillons in the collision region. The original (nearly) planar symmetry has been completely destroyed at this point and an accurate study of the system requires the full three-dimensional simulation.

  16. Cosmic bubble and domain wall instabilities II: fracturing of colliding walls

    Energy Technology Data Exchange (ETDEWEB)

    Braden, Jonathan; Bond, J. Richard [CITA, University of Toronto, 60 St. George Street, Toronto, ON, M5S 3H8 (Canada); Mersini-Houghton, Laura, E-mail: j.braden@ucl.ac.uk, E-mail: bond@cita.utoronto.ca, E-mail: mersini@physics.unc.edu [Department of Physics and Astronomy, University of North Carolina-Chapel Hill, 1 Phillips Hall, 120 E. Cameron Avenue, Chapel Hill, NC 27599-3255 (United States)

    2015-08-01

    We study collisions between nearly planar domain walls including the effects of small initial nonplanar fluctuations. These perturbations represent the small fluctuations that must exist in a quantum treatment of the problem. In a previous paper, we demonstrated that at the linear level a subset of these fluctuations experience parametric amplification as a result of their coupling to the planar symmetric background. Here we study the full three-dimensional nonlinear dynamics using lattice simulations, including both the early time regime when the fluctuations are well described by linear perturbation theory as well as the subsequent stage of fully nonlinear evolution. We find that the nonplanar fluctuations have a dramatic effect on the overall evolution of the system. Specifically, once these fluctuations begin to interact nonlinearly the split into a planar symmetric part of the field and the nonplanar fluctuations loses its utility. At this point the colliding domain walls dissolve, with the endpoint of this being the creation of a population of oscillons in the collision region. The original (nearly) planar symmetry has been completely destroyed at this point and an accurate study of the system requires the full three-dimensional simulation.

  17. Cosmic bubble and domain wall instabilities II: fracturing of colliding walls

    International Nuclear Information System (INIS)

    Braden, Jonathan; Bond, J. Richard; Mersini-Houghton, Laura

    2015-01-01

    We study collisions between nearly planar domain walls including the effects of small initial nonplanar fluctuations. These perturbations represent the small fluctuations that must exist in a quantum treatment of the problem. In a previous paper, we demonstrated that at the linear level a subset of these fluctuations experience parametric amplification as a result of their coupling to the planar symmetric background. Here we study the full three-dimensional nonlinear dynamics using lattice simulations, including both the early time regime when the fluctuations are well described by linear perturbation theory as well as the subsequent stage of fully nonlinear evolution. We find that the nonplanar fluctuations have a dramatic effect on the overall evolution of the system. Specifically, once these fluctuations begin to interact nonlinearly the split into a planar symmetric part of the field and the nonplanar fluctuations loses its utility. At this point the colliding domain walls dissolve, with the endpoint of this being the creation of a population of oscillons in the collision region. The original (nearly) planar symmetry has been completely destroyed at this point and an accurate study of the system requires the full three-dimensional simulation

  18. Effect of two dimensional heat conduction within the wall on heat transfer of a tube partially heated on its circumference

    International Nuclear Information System (INIS)

    Satoh, Isao; Kurosaki, Yasuo

    1987-01-01

    This paper dealt with the numerical calculations of the heat transfer of a tube partially heated on its circumference, considering two-dimensional heat conduction within the wall. The contribution of the unheated region of the tube wall to heat tranfer of the heated region was explained by the term of 'fin efficiency of psuedo-fin', it was clarified that the fin efficiency of the unheated region was little affected by the temperature difference between the inner and outer surfaces of the wall, and could be approximated by the fin efficency of a rectangular fin. Both the circumferential and radial heat conductions within the wall affected the temperature difference between the inner and outer surfaces of the heated region; however, the effect of the temperature difference on the circumferentially average Nusselt number could be obtained by using the analytical solution of radially one-dimensional heat conduction. Using these results, a diagram showing the effect of wall conduction on heat transfer, which is useful for designing the circumferentially nonuniformly heated coolant passages, was obtained. (author)

  19. Anterior Abdominal Wall Desmoids Tumor in a Five Year Old Girl – A ...

    African Journals Online (AJOL)

    Desmoid tumors are rare, slow – growing, mesenchymal monoclinic proliferation. It may occur as intra-abdominal tumor usually affecting the mesentery of the intestine or it could be extra-abdominal in which they may affect the popliteal region, the chest wall or the anterior abdominal wall. Reports in children less than 10 ...

  20. Embolotherapy using N-butyl cyanoacrylate for abdominal wall bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Ho; Koh, Young Hwan; Han, Dae Hee; Kim, Ji Hoon; Cha, Joo Hee; Lee, Eun Hye; Song, Chi Sung [Seoul National University Boramae Hospital, Seoul (Korea, Republic of)

    2008-05-15

    We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n =2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinical on an outpatient basis. NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding.

  1. Embolotherapy using N-butyl cyanoacrylate for abdominal wall bleeding

    International Nuclear Information System (INIS)

    Choi, Young Ho; Koh, Young Hwan; Han, Dae Hee; Kim, Ji Hoon; Cha, Joo Hee; Lee, Eun Hye; Song, Chi Sung

    2008-01-01

    We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n =2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinical on an outpatient basis. NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding

  2. Effect of percutaneous renal sympathetic nerve radiofrequency ablation in patients with severe heart failure.

    Science.gov (United States)

    Dai, Qiming; Lu, Jing; Wang, Benwen; Ma, Genshan

    2015-01-01

    This study aimed to investigate the clinical feasibility and effects of percutaneous renal sympathetic nerve radiofrequency ablation in patients with heart failure. A total of 20 patients with heart failure were enrolled, aged from 47 to 75 years (63±10 years). They were divided into the standard therapy (n = 10), and renal nerve radiofrequency ablation groups (n = 10). There were 15 males and 5 female patients, including 8 ischemic cardiomyopathy, 8 dilated cardiomyopathy, and 8 hypertensive cardiopathy. All of the patients met the criteria of New York Heart Association classes III-IV cardiac function. Patients with diabetes and renal failure were excluded. Percutaneous renal sympathetic nerve radiofrequency ablation was performed on the renal artery wall under X-ray guidance. Serum electrolytes, neurohormones, and 24 h urine volume were recorded 24 h before and after the operation. Echocardiograms were performed to obtain left ventricular ejection fraction at baseline and 6 months. Heart rate, blood pressure, symptoms of dyspnea and edema were also monitored. After renal nerve ablation, 24 h urine volume was increased, while neurohormone levels were decreased compared with those of pre-operation and standard therapy. No obvious change in heart rate or blood pressure was recorded. Symptoms of heart failure were improved in patients after the operation. No complications were recorded in the study. Percutaneous renal sympathetic nerve radiofrequency ablation may be a feasible, safe, and effective treatment for the patients with severe congestive heart failure.

  3. Measurement of the near-wall velocity profile for a nanofluid flow inside a microchannel

    Science.gov (United States)

    Kanjirakat, Anoop; Sadr, Reza

    2015-11-01

    Hydrodynamics and anomalous heat transfer enhancements have been reported in the past for colloidal suspensions of nano-sized particles dispersed in a fluid (nanofluids). However, such augmentations may manifest itself by study of fluid flow characteristics near in the wall region. Present experimental study reports near-wall velocity profile for nanofluids (silicon dioxide nanoparticles in water) measured inside a microchannel. An objective-based nano-Particle Image Velocimetry (nPIV) technique is used to measure fluid velocity within three visible depths, O(100nm), from the wall. The near-wall fluid velocity profile is estimated after implementing the required corrections for optical properties and effects caused by hindered Brownian motion, wall-particle interactions, and non-uniform exponential illumination on the measurement technique. The fluid velocities of nanofluids at each of the three visible depths are observed to be higher than that of the base fluid resulting in a higher shear rate in this region. The relative increase in shear rates for nanofluids is believed to be the result of the near-wall shear-induced particle migration along with the Brownian motion of the nanoparticles. This research is funded by NPRP grant # 08-574-2-239 from the Qatar National Research Fund (a member of Qatar Foundation).

  4. First wall and blanket stresses induced by cyclic fusion core operations

    International Nuclear Information System (INIS)

    Bohachevsky, I.O.; Kostoff, R.N.

    1981-01-01

    An analysis is made of cyclic thermal loads and stresses for the complete range of operating conditions. Two critical components were examined; the solid wall adjacent to the fusion plasma (first wall) and the fuel elements in the high power density region of the blanket. Simple closed form expressions were derived for temperature increases and thermal stresses that may be evaluated conveniently and rapidly and the values compared for different systems

  5. Particles in wall-bounded turbulent flows deposition, re-suspension and agglomeration

    CERN Document Server

    Pozorski, Jacek

    2017-01-01

    The book presents an up-to-date review of turbulent two-phase flows with the dispersed phase, with an emphasis on the dynamics in the near-wall region. New insights to the flow physics are provided by direct numerical simuation and by fine experimental techniques. Also included are models of particle dynamics in wall-bounded turbulent flows, and a description of particle surface interactions including muti-layer deposition and re-suspension.

  6. Correction of the kinetic blur and representation of heart dynamics in nuclear imagery

    International Nuclear Information System (INIS)

    Ignaszewski, A.; Vaillant, D.; Sabatier, J.P.; Fernandez, Y.

    1975-01-01

    In heart cavity studies the simplicity and harmlessness nuclear imagery are great advantages, but it is necessary to improve on the data obtainable by this technique. The usual image is faulty, owing to the presence of a kinetic softness, and deficient because it fails to account for the mobility of the walls. An attempt was made to correct the kinetic softness on an image and to reconstitute the film of a heart cycle, an aim achieved by combining a computer with the camera. The examination conditions generally adopted include storage of all data and a reconstitution of the entire cycle is programmed taking a multiple time unit of 20ms; this supplies a sequence of images which when observed in succession resembles the heat contractility film [fr

  7. Fuel retention in JET ITER-Like Wall from post-mortem analysis

    Energy Technology Data Exchange (ETDEWEB)

    Heinola, K., E-mail: kalle.heinola@ccfe.ac.uk [Association EURATOM-TEKES, University of Helsinki, PO Box 64, 00560 Helsinki (Finland); EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Widdowson, A. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Likonen, J. [Association EURATOM-TEKES, VTT, PO Box 1000, 02044 VTT, Espoo (Finland); Alves, E. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Baron-Wiechec, A. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Barradas, N. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Brezinsek, S. [Forschungszentrum Julich GmbH, EURATOM Association, D-52425 Julich (Germany); Catarino, N. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Coad, P. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Koivuranta, S. [Association EURATOM-TEKES, VTT, PO Box 1000, 02044 VTT, Espoo (Finland); Matthews, G.F. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Mayer, M. [Max-Planck Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Petersson, P. [Royal Institute of Technology, Association EURATOM-VR, SE-10044 Stockholm (Sweden)

    2015-08-15

    Selected Ion Beam Analysis techniques applicable for detecting deuterium and heavier impurities have been used in the post-mortem analyses of tiles removed after the first JET ITER-Like Wall (JET-ILW) campaign. Over half of the retained fuel was measured in the divertor region. The highest figures for fuel retention were obtained from regions with the thickest deposited layers, i.e. in the inner divertor on top of tile 1 and on the High Field Gap Closure tile, which resides deep in the plasma scrape-off layer. Least retention was found in the main chamber high erosion regions, i.e. in the mid-plane of Inner Wall Guard Limiter. The fuel retention values found typically varied with deposition layer thicknesses. The reported retention values support the observed decrease in fuel retention obtained with gas balance experiments of JET-ILW.

  8. Prospective Heart Tracking for Whole-heart Magnetic Resonance Angiography

    Science.gov (United States)

    Moghari, Mehdi H.; Geva, Tal; Powell, Andrew J.

    2015-01-01

    Purpose To develop a prospective respiratory-gating technique (Heart-NAV) for use with contrast-enhanced 3D inversion recovery (IR) whole-heart magnetic resonance angiography (MRA) acquisitions that directly tracks heart motion without creating image inflow artifact. Methods With Heart-NAV, 1 of the startup pulses for the whole-heart steady-state free precession MRA sequence is used to collect the centerline of k-space, and its 1-dimensional reconstruction is fed into the standard diaphragm-navigator (NAV) signal analysis process to prospectively gate and track respiratory-induced heart displacement. Ten healthy volunteers underwent non-contrast whole-heart MRA acquisitions using the conventional diaphragm-NAV and Heart-NAV with 5 and 10 mm acceptance windows in a 1.5T scanner. Five patients underwent contrast-enhanced IR whole-heart MRA using a diaphragm-NAV and Heart-NAV with a 5 mm acceptance window. Results For non-contrast whole-heart MRA with both the 5 and 10 mm acceptance windows, Heart-NAV yielded coronary artery vessel sharpness and subjective visual scores that were not significantly different than those using a conventional diaphragm-NAV. Scan time for Heart-NAV was 10% shorter (p<0.05). In patients undergoing contrast-enhanced IR whole-heart MRA, inflow artifact was seen with the diaphragm-NAV but not with Heart-NAV. Conclusion Compared to a conventional diaphragm-NAV, Heart-NAV achieves similar image quality in a slightly shorter scan time and eliminates inflow artifact. PMID:26843458

  9. Generalized wall function and its application to compressible turbulent boundary layer over a flat plate

    Science.gov (United States)

    Liu, J.; Wu, S. P.

    2017-04-01

    Wall function boundary conditions including the effects of compressibility and heat transfer are improved for compressible turbulent boundary flows. Generalized wall function formulation at zero-pressure gradient is proposed based on coupled velocity and temperature profiles in the entire near-wall region. The parameters in the generalized wall function are well revised. The proposed boundary conditions are integrated into Navier-Stokes computational fluid dynamics code that includes the shear stress transport turbulence model. Numerical results are presented for a compressible boundary layer over a flat plate at zero-pressure gradient. Compared with experimental data, the computational results show that the generalized wall function reduces the first grid spacing in the directed normal to the wall and proves the feasibility and effectivity of the generalized wall function method.

  10. Preoperative atrial fibrillation and long-term survival after open heart surgery in a rural tertiary heart institute.

    Science.gov (United States)

    O'Neal, Wesley T; Efird, Jimmy T; Davies, Stephen W; Choi, Yuk Ming; Anderson, Curtis A; Kindell, Linda C; O'Neal, Jason B; Ferguson, T Bruce; Chitwood, W Randolph; Kypson, Alan P

    2013-01-01

    Preoperative atrial fibrillation (AF) is associated with increased morbidity and mortality after open heart surgery. However, the impact of preoperative AF on long-term survival after open heart surgery has not been widely examined in rural populations. Patients from rural regions are less likely to receive treatment for cardiac conditions and to have adequate medical insurance coverage. To examine the influence of preoperative AF on long-term survival following open heart surgery in rural eastern North Carolina. Long-term survival was compared in patients with and without preoperative AF after coronary artery bypass grafting (CABG) and CABG plus valve (CABG + V) surgery between 2002 and 2011. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model. The study population consisted of 5438 patients. A total of 263 (5%) patients had preoperative AF. Preoperative AF was an independent predictor of long-term survival (open heart surgery: adjusted HR = 1.6, 95% CI = 1.3-2.0; CABG: adjusted HR = 1.6, 95% CI = 1.3-2.1; CABG + V: adjusted HR = 1.6, 95% CI = 1.1-2.3). Preoperative AF is an important predictor of long-term survival after open heart surgery in this rural population. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Near wall turbulence: An experimental view

    Science.gov (United States)

    Stanislas, Michel

    2017-10-01

    The present paper draws upon the experience of the author to illustrate the potential of advanced optical metrology for understanding near-wall-turbulence physics. First the canonical flat plate boundary layer problem is addressed, initially very near to the wall and then in the outer region when the Reynolds number is high enough to generate an outer turbulence peak. The coherent structure organization is examined in detail with the help of stereoscopic particle image velocimetry (PIV). Then the case of a turbulent boundary layer subjected to a mild adverse pressure gradient is considered. The results obtained show the great potential of a joint experimental-numerical approach. The conclusion is that the insight provided by today's optical metrology opens the way for significant improvements in turbulence modeling in upcoming years.

  12. Edge states in gated bilayer-monolayer graphene ribbons and bilayer domain walls

    Science.gov (United States)

    Mirzakhani, M.; Zarenia, M.; Peeters, F. M.

    2018-05-01

    Using the effective continuum model, the electron energy spectrum of gated bilayer graphene with a step-like region of decoupled graphene layers at the edge of the sample is studied. Different types of coupled-decoupled interfaces are considered, i.e., zigzag (ZZ) and armchair junctions, which result in significant different propagating states. Two non-valley-polarized conducting edge states are observed for ZZ type, which are mainly located around the ZZ-ended graphene layers. Additionally, we investigated both BA-BA and BA-AB domain walls in the gated bilayer graphene within the continuum approximation. Unlike the BA-BA domain wall, which exhibits gapped insulating behaviour, the domain walls surrounded by different stackings of bilayer regions feature valley-polarized edge states. Our findings are consistent with other theoretical calculations, such as from the tight-binding model and first-principles calculations, and agree with experimental observations.

  13. Impaired mitochondrial function in chronically ischemic human heart

    DEFF Research Database (Denmark)

    Stride, Nis Ottesen; Larsen, Steen; Hey-Mogensen, Martin

    2013-01-01

    , and finally to assess myocardial antioxidant levels. Mitochondrial respiration in biopsies from ischemic and nonischemic regions from the left ventricle of the same heart was compared in nine human subjects. Maximal oxidative phosphorylation capacity in fresh muscle fibers was lower in ischemic compared.......05), and the levels of antioxidant protein expression was lower. Diminished mitochondrial respiration capacity and excessive ROS production demonstrate an impaired mitochondrial function in ischemic human heart muscle. No chronic ischemic preconditioning effect was found....

  14. Resistive wall mode active control physics design for KSTAR

    International Nuclear Information System (INIS)

    Park, Y. S.; Sabbagh, S. A.; Bialek, J. M.; Berkery, J. W.; Bak, J. G.; Lee, S. G.; Oh, Y. K.

    2014-01-01

    As KSTAR H-mode operation approaches the region where the resistive wall mode (RWM) can be unstable, an important issue for future long pulse, high beta plasma operation is to evaluate RWM active feedback control performance using a planned active/passive RWM stabilization system on the device. In particular, an optimal design of feedback sensors allows mode stabilization up to the highest achievable β N close to the ideal with-wall limit, β N wall , with reduced control power requirements. The computed ideal n = 1 mode structure from the DCON code has been input to the VALEN-3D code to calculate the projected performance of an active RWM control system in the KSTAR three-dimensional conducting structure device geometry. Control performance with the midplane locked mode detection sensors, off-midplane saddle loops, and magnetic pickup coils is examined. The midplane sensors measuring the radial component of the mode perturbation is found to be strongly affected by the wall eddy current. The off-axis saddle loops with proper compensation of the prompt applied field are computed to provide stabilization at β N up to 86% of β N wall but the low RWM amplitude computed in the off-axis regions near the sensors can produce a low signal-to-noise ratio. The required control power and bandwidth are also estimated with varied noise levels in the feedback sensors. Further improvements have been explored by examining a new RWM sensor design motivated by the off-midplane poloidal magnetic field sensors in NSTX. The new sensors mounted off of the copper passive stabilizer plates near the device midplane show a clear advantage in control performance corresponding to achieving 99% of β N wall without the need of compensation of the prompt field. The result shows a significant improvement of RWM feedback stabilization using the new sensor set which motivates a future feedback sensor upgrade

  15. Influence of cold walls on PET image quantification and volume segmentation: A phantom study

    International Nuclear Information System (INIS)

    Berthon, B.; Marshall, C.; Edwards, A.; Spezi, E.; Evans, M.

    2013-01-01

    Purpose: Commercially available fillable plastic inserts used in positron emission tomography phantoms usually have thick plastic walls, separating their content from the background activity. These “cold” walls can modify the intensity values of neighboring active regions due to the partial volume effect, resulting in errors in the estimation of standardized uptake values. Numerous papers suggest that this is an issue for phantom work simulating tumor tissue, quality control, and calibration work. This study aims to investigate the influence of the cold plastic wall thickness on the quantification of 18F-fluorodeoxyglucose on the image activity recovery and on the performance of advanced automatic segmentation algorithms for the delineation of active regions delimited by plastic walls.Methods: A commercial set of six spheres of different diameters was replicated using a manufacturing technique which achieves a reduction in plastic walls thickness of up to 90%, while keeping the same internal volume. Both sets of thin- and thick-wall inserts were imaged simultaneously in a custom phantom for six different tumor-to-background ratios. Intensity values were compared in terms of mean and maximum standardized uptake values (SUVs) in the spheres and mean SUV of the hottest 1 ml region (SUV max , SUV mean , and SUV peak ). The recovery coefficient (RC) was also derived for each sphere. The results were compared against the values predicted by a theoretical model of the PET-intensity profiles for the same tumor-to-background ratios (TBRs), sphere sizes, and wall thicknesses. In addition, ten automatic segmentation methods, written in house, were applied to both thin- and thick-wall inserts. The contours obtained were compared to computed tomography derived gold standard (“ground truth”), using five different accuracy metrics.Results: The authors' results showed that thin-wall inserts achieved significantly higher SUV mean , SUV max , and RC values (up to 25%, 16

  16. Towards grid-converged wall-modeled LES of atmospheric boundary layer flows

    Science.gov (United States)

    Yellapantula, Shashank; Vijayakumar, Ganesh; Henry de Frahan, Marc; Churchfield, Matthew; Sprague, Michael

    2017-11-01

    Accurate characterization of incoming atmospheric boundary layer (ABL) turbulence is a critical factor in improving accuracy and predictive nature of simulation of wind farm flows. Modern commercial wind turbines operate in the log layer of the ABL that are typically simulated using wall-modeled large-eddy simulation (WMLES). One of the long-standing issues associated with wall modeling for LES and hybrid RANS-LES for atmospheric boundary layers is the over-prediction of the mean-velocity gradient, commonly referred to as log-layer mismatch. Kawai and Larsson in 2012, identified under-resolution of the near-wall region and the incorrect information received by the wall model as potential causes for the log-layer mismatch in WMLES of smooth-wall boundary-layer flows. To solve the log layer mismatch issue, they proposed linking the wall model to the LES solution at a physical of height of ym, instead of the first grid point. In this study, we extend their wall modeling approach to LES of the rough-wall ABL to investigate issues of log-layer mismatch and grid convergence. This work was funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Wind Energy Technologies Office, under Contract No. DE-AC36-08-GO28308 with the National Renewable Energy Laboratory.

  17. Wall Shear Stress, Wall Pressure and Near Wall Velocity Field Relationships in a Whirling Annular Seal

    Science.gov (United States)

    Morrison, Gerald L.; Winslow, Robert B.; Thames, H. Davis, III

    1996-01-01

    The mean and phase averaged pressure and wall shear stress distributions were measured on the stator wall of a 50% eccentric annular seal which was whirling in a circular orbit at the same speed as the shaft rotation. The shear stresses were measured using flush mounted hot-film probes. Four different operating conditions were considered consisting of Reynolds numbers of 12,000 and 24,000 and Taylor numbers of 3,300 and 6,600. At each of the operating conditions the axial distribution (from Z/L = -0.2 to 1.2) of the mean pressure, shear stress magnitude, and shear stress direction on the stator wall were measured. Also measured were the phase averaged pressure and shear stress. These data were combined to calculate the force distributions along the seal length. Integration of the force distributions result in the net forces and moments generated by the pressure and shear stresses. The flow field inside the seal operating at a Reynolds number of 24,000 and a Taylor number of 6,600 has been measured using a 3-D laser Doppler anemometer system. Phase averaged wall pressure and wall shear stress are presented along with phase averaged mean velocity and turbulence kinetic energy distributions located 0.16c from the stator wall where c is the seal clearance. The relationships between the velocity, turbulence, wall pressure and wall shear stress are very complex and do not follow simple bulk flow predictions.

  18. Total contact cast wall load in patients with a plantar forefoot ulcer and diabetes.

    Science.gov (United States)

    Begg, Lindy; McLaughlin, Patrick; Vicaretti, Mauro; Fletcher, John; Burns, Joshua

    2016-01-01

    The total contact cast (TCC) is an effective intervention to reduce plantar pressure in patients with diabetes and a plantar forefoot ulcer. The walls of the TCC have been indirectly shown to bear approximately 30 % of the plantar load. A new direct method to measure inside the TCC walls with capacitance sensors has shown that the anterodistal and posterolateral-distal regions of the lower leg bear the highest load. The objective of this study was to directly measure these two regions in patients with Diabetes and a plantar forefoot ulcer to further understand the mechanism of pressure reduction in the TCC. A TCC was applied to 17 patients with Diabetes and a plantar forefoot ulcer. TCC wall load (contact area, peak pressure and max force) at the anterodistal and posterolateral-distal regions of the lower leg were evaluated with two capacitance sensor strips measuring 90 cm(2) (pliance®, novel GmbH, Germany). Plantar load (contact area, peak pressure and max force) was measured with a capacitance sensor insole (pedar®, novel GmbH, Germany) placed inside the TCC. Both pedar® and pliance® collected data simultaneously at a sampling rate of 50Hz synchronised to heel strike. The magnitude of TCC wall load as a proportion of plantar load was calculated. The TCC walls were then removed to determine the differences in plantar loading between the TCC and the cut down shoe-cast for the whole foot, rearfoot, midfoot and forefoot (region of interest). TCC wall load was substantial. The anterodistal lower leg recorded 48 % and the posterolateral-distal lower leg recorded 34 % of plantar contact area. The anterodistal lower leg recorded 28 % and the posterolateral-distal lower leg recorded 12 % of plantar peak pressure. The anterodistal lower leg recorded 12 % and the posterolateral-distal lower leg recorded 4 % of plantar max force. There were significant differences in plantar load between the TCC and the cut down shoe-cast for the whole foot, rearfoot, midfoot and

  19. Echocardiography Differences Between Athlete's Heart Hearth and Hypertrophic Cardiomyopathy.

    Science.gov (United States)

    Kreso, Amir; Barakovic, Fahir; Medjedovic, Senad; Halilbasic, Amila; Klepic, Muhamed

    2015-10-01

    Among long term athletes there is always present hypertrophy of the left ventricle walls as well as increased cardiac mass. These changes are the result of the heart muscle adaptation to load during the years of training, which should not be considered as pathology. In people suffering from hypertrophic cardiomyopathy (HCM), there is also present hypertrophy of the left ventricle walls and increased mass of the heart, but these changes are the result of pathological changes in the heart caused by a genetic predisposition for the development HCM of. Differences between myocardial hypertrophy in athletes and HCM are not clearly differentiated and there are always dilemmas between pathological and physiological hypertrophy. The goal of the study is to determine and compare the echocardiographic cardiac parameters of longtime athletes to patients with hypertrophic cardiomyopathy. The study included 60 subjects divided into two groups: active athletes and people with hypertrophic cardiomyopathy. Mean values of IVSd recorded in GB is IVSd=17.5 mm (n=20, 95% CI, 16.00-19.00 mm), while a significantly smaller mean value is recorded in GA, IVSd=10.0 mm (n=40, 95% CI, 9.00-11.00 mm). The mean value of the left ventricle in diastole (LVDd) recorded in the GA is LVDd=51 mm (n=40; 95% CI, 48.00 to 52.00 mm), while in the group with hypertrophic cardiomyopathy (GB) mean LVDd value is 42 mm (n=20; 95% CI, 40.00 to 48.00 mm). The mean value of the rear wall of the left ventricle (LVPWd) recorded in the GA is LVDd=10 mm (n=40; 95% CI, 9.00-10.00 mm) while in the group with hypertrophic cardiomyopathy (GB) mean LVDd is 14 mm (n=20; 95% CI, 12.00 to 16.00 mm). The mean of the left ventricle during systole (LVSD) observed in GA is LVSD=34 mm (n=40; 95% CI, 32.00 to 36.00 mm), while in the group with hypertrophic cardiomyopathy (GB) mean LVSD is 28 mm (n=20; 95% CI, 24.00 to 28.83 mm). The mean ejection fraction (EF%) observed in GA is EF=60% (n=40; 95% CI, 56.41 to 63.00%), while in

  20. Evaluation of a Thermoplastic Immobilization System for Breast and Chest Wall Radiation Therapy

    International Nuclear Information System (INIS)

    Strydhorst, Jared H.; Caudrelier, Jean-Michel; Clark, Brenda G.; Montgomery, Lynn A.; Fox, Greg; MacPherson, Miller S.

    2011-01-01

    We report on the impact of a thermoplastic immobilization system on intra- and interfraction motion for patients undergoing breast or chest wall radiation therapy. Patients for this study were treated using helical tomotherapy. All patients were immobilized using a thermoplastic shell extending from the shoulders to the ribcage. Intrafraction motion was assessed by measuring maximum displacement of the skin, heart, and chest wall on a pretreatment 4D computed tomography, while inter-fraction motion was inferred from patient shift data arising from daily image guidance procedures on tomotherapy. Using thermoplastic immobilization, the average maximum motion of the external contour was 1.3 ± 1.6 mm, whereas the chest wall was found to be 1.6 ± 1.9 mm. The day-to-day setup variation was found to be large, with random errors of 4.0, 12.0, and 4.5 mm in the left-right, superior-inferior, and anterior-posterior directions, respectively, and the standard deviations of the systematic errors were found to be 2.7, 9.8, and 4.1 mm. These errors would be expected to dominate any respiratory motion but can be mitigated by daily online image guidance. Using thermoplastic immobilization can effectively reduce respiratory motion of the chest wall and external contour, but these gains can only be realized if daily image guidance is used.

  1. A case of Wolf-Hirschhorn syndrome and hypoplastic left heart syndrome.

    Science.gov (United States)

    von Elten, Kelley; Sawyer, Taylor; Lentz-Kapua, Sarah; Kanis, Adam; Studer, Matthew

    2013-06-01

    Wolf-Hirschhorn Syndrome (WHS) is a genetic syndrome that includes a typical facial appearance, mental retardation, growth delay, seizures, and congenital cardiac defects. A deletion of the terminal band of the short arm of chromosome 4, with a breakpoint at the 4p15 to 4p16 region, is the most common genetic mutation causing WHS. Congenital heart disease associated with WHS typically includes atrial and ventricular septal defects, though there are a few case reports of associated complex congenital heart disease. Here we report a case of an infant with a large 4p deletion, with a breakpoint at the 4p12 region, and hypoplasic left heart syndrome. We discuss a possible link between the size of the chromosomal deletion in WHS and the severity of the cardiac defect.

  2. Ambiguous walls

    DEFF Research Database (Denmark)

    Mody, Astrid

    2012-01-01

    The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how walls...... have encouraged architectural thinking of enclosure, materiality, construction and inhabitation in architectural history, the paper’s aim is to define new directions for the integration of LEDs in walls, challenging the thinking of inhabitation and program. This paper introduces the notion...... of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...

  3. Spatially resolved RNA-sequencing of the embryonic heart identifies a role for Wnt/β-catenin signaling in autonomic control of heart rate

    Science.gov (United States)

    Burkhard, Silja Barbara

    2018-01-01

    Development of specialized cells and structures in the heart is regulated by spatially -restricted molecular pathways. Disruptions in these pathways can cause severe congenital cardiac malformations or functional defects. To better understand these pathways and how they regulate cardiac development we used tomo-seq, combining high-throughput RNA-sequencing with tissue-sectioning, to establish a genome-wide expression dataset with high spatial resolution for the developing zebrafish heart. Analysis of the dataset revealed over 1100 genes differentially expressed in sub-compartments. Pacemaker cells in the sinoatrial region induce heart contractions, but little is known about the mechanisms underlying their development. Using our transcriptome map, we identified spatially restricted Wnt/β-catenin signaling activity in pacemaker cells, which was controlled by Islet-1 activity. Moreover, Wnt/β-catenin signaling controls heart rate by regulating pacemaker cellular response to parasympathetic stimuli. Thus, this high-resolution transcriptome map incorporating all cell types in the embryonic heart can expose spatially restricted molecular pathways critical for specific cardiac functions. PMID:29400650

  4. Laminar boundary layer near the rotating end wall of a confined vortex

    Science.gov (United States)

    Shakespeare, W. J.; Levy, E. K.

    1982-06-01

    The results of an experimental and theoretical investigation of the fluid mechanics in a confined vortex are discussed with particular emphasis on behavior away from the axis of symmetry and near the end walls. The vortex is generated in a rotating cylindrical chamber with an exit opening in one end. Both end walls rotate. For the range of flow rates and swirl ratios (S between 1 and 5) of interest here, the flow field far from the end walls behaves as inviscid and irrotational; and the end wall boundary layers are thin and laminar. Measurements and calculations of tangential and radial velocity in the end wall region show the development of a secondary flow resulting in a strong velocity 'overshoot' in the radial component. Results illustrating the nature of the velocity variations on the end walls are presented; and it is shown that the mass flow rate through the end wall boundary layers, while only a small fraction of the total flow, increases with increasing swirl and with decreasing total flow rate through the chamber.

  5. Time Resolved Tomographic PIV Measurements of Rough-Wall Turbulent Channel Flow

    Science.gov (United States)

    Miorini, Rinaldo; Zhang, Cao; Katz, Joseph

    2013-11-01

    Time resolved tomographic PIV is used to study flow structures in the outer region of a rough-wall turbulent boundary layer, focusing on imprints of the roughness on the outer layer. Measurements are performed in a transparent channel installed in the JHU optically index matched facility. The roughness consists of pyramids with height, k = 0.46 mm, and wavelength, λ = 3.2 mm, satisfying h/k = 55 (h = 25.4 mm is the channel half-height), k + = 64 and Re = 40000. The TPIV setup consists of four high-speed cameras operating at 3 kHz, which view the sample volume through acrylic prisms. The flow field is illuminated by an Nd:YLF laser. Following enhancement, calibration, and reconstruction, 643 voxels interrogation volumes with 0.75 overlap provide 3D velocity fields with spacing of 0.5883 mm3. Formation and transport of near-wall 3D U-shaped vortex structures, with base in front of the pyramids, and quasi-streamwise legs extending between pyramid crest lines are evident from the data. Extended streamwise regions of high wall-normal vorticity appear ``latched'' to the roughness elements close to the wall, but are transported downstream at higher elevations. Also evident are traveling streamwise low velocity streaks, which cover many roughness elements. Sponsored by NSF CBET and ONR.

  6. Investigation of the Geometry of Metal Tube Walls after Necking in Uniaxial Tension

    Directory of Open Access Journals (Sweden)

    Chong Li

    2017-03-01

    Full Text Available Abstract: In order to characterize the deformation and true stress–strain relation of metal tubes, the geometry of tube walls after necking in uniaxial tension need to be determined. The paper investigated the necking process of metal tube. A large number of tensile tests and finite element analysis of 1Cr18Ni9Ti tubes with different sizes were conducted. It was found that the geometry of outer tube wall in the necking region can be described using a logistic regression model. The final geometry of the tube is determined by original tube diameter and wall thickness. The offset of tube walls are affected by two competing factors: volume constancy and necking. The offset distances of outer and inner walls are mainly affected by original wall thickness. The length of the necking zone is more influenced by original tube diameter. Tube elongation at fracture increases slightly as tube diameter gets larger, while the wall thickness has almost no impact on the elongation.

  7. Heart Failure

    Science.gov (United States)

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  8. Prediction of the external work of the native heart from the dynamic H-Q curves of the rotary blood pumps during left heart bypass.

    Science.gov (United States)

    Yokoyama, Yoshimasa; Kawaguchi, Osamu; Kitao, Takashi; Kimura, Taro; Steinseifer, Ulrich; Takatani, Setsuo

    2010-09-01

    The ventricular performance is dependent on the drainage effect of rotary blood pumps (RBPs) and the performance of RBPs is affected by the ventricular pulsation. In this study, the interaction between the ventricle and RBPs was examined using the pressure-volume (P-V) diagram of the ventricle and dynamic head pressure-bypass flow (H-Q) curves (H, head pressure: arterial pressure minus ventricular pressure vs. Q, bypass flow) of the RBPs. We first investigated the relationships in a mock loop with a passive fill ventricle, followed by validation in ex vivo animal experiments. An apical drainage cannula with a micro-pressure sensor was especially fabricated to obtain ventricular pressure, while three pairs of ultrasonic crystals placed on the heart wall were used to derive ventricular volume. The mock loop-configured ventricular apical-descending aorta bypass revealed that the external work of the ventricle expressed by the area inside the P-V diagrams (EW(Heart) ) correlated strongly with the area inside dynamic H-Q curves (EW(VAD)), with the coefficients of correlation being R² = 0.869 ∼ 0.961. The results in the mock loop were verified in the ex vivo studies using three Shiba goats (10-25 kg in body weight), showing the correlation coefficients of R² = 0.802 ∼ 0.817. The linear regression analysis indicated that the increase in the bypass flow reduced pulsatility in the ventricle expressed in EW(Heart) as well as in EW(VAD) . Experimental results, both mock loop and animal studies, showed that the interaction between cardiac external work and H-Q performance of RBPs can be expressed by the relationships "EW(Heart) versus EW(VAD) ." The pulsatile nature of the native heart can be expressed in the area underneath the H-Q curves of RBPs EW(VAD) during left heart bypass indicating the status of the level of assistance by RBPs and the native heart function. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and

  9. High-R Walls for Remodeling: Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J.; Kochkin, V.

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  10. High-R Walls for Remodeling. Wall Cavity Moisture Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States); Kochkin, V. [NAHB Research Center Industry Partnership, Upper Marlboro, MD (United States)

    2012-12-01

    The focus of the study is on the performance of wall systems, and in particular, the moisture characteristics inside the wall cavity and in the wood sheathing. Furthermore, while this research will initially address new home construction, the goal is to address potential moisture issues in wall cavities of existing homes when insulation and air sealing improvements are made.

  11. Global and regional brain mean diffusivity changes in patients with heart failure.

    Science.gov (United States)

    Woo, Mary A; Palomares, Jose A; Macey, Paul M; Fonarow, Gregg C; Harper, Ronald M; Kumar, Rajesh

    2015-04-01

    Heart failure (HF) patients show gray and white matter changes in multiple brain sites, including autonomic and motor coordination areas. It is unclear whether the changes represent acute or chronic tissue pathology, a distinction necessary for understanding pathological processes that can be resolved with diffusion tensor imaging (DTI)-based mean diffusivity (MD) procedures. We collected four DTI series from 16 HF (age 55.1 ± 7.8 years, 12 male) and 26 control (49.7 ± 10.8 years, 17 male) subjects with a 3.0-Tesla magnetic resonance imaging scanner. MD maps were realigned, averaged, normalized, and smoothed. Global and regional MD values from autonomic and motor coordination sites were calculated by using normalized MD maps and brain masks; group MD values and whole-brain smoothed MD maps were compared by analysis of covariance (covariates; age and gender). Global brain MD (HF vs. controls, units × 10(-6) mm(2) /sec, 1103.8 ± 76.6 vs. 1035.9 ± 69.4, P = 0.038) and regional autonomic and motor control site values (left insula, 1,085.4 ± 95.7 vs. 975.7 ± 65.4, P = 0.001; right insula, 1,050.2 ± 100.6 vs. 965.7 ± 58.4, P = 0.004; left hypothalamus, 1,419.6 ± 165.2 vs. 1,234.9 ± 136.3, P = 0.002; right hypothalamus, 1,446.5 ± 178.8 vs. 1,273.3 ± 136.9, P = 0.004; left cerebellar cortex, 889.1 ± 81.9 vs. 796.6 ± 46.8, P right cerebellar cortex, 797.8 ± 50.8 vs. 750.3 ± 27.5, P = 0.001; cerebellar deep nuclei, 1,236.1 ± 193.8 vs. 1,071.7 ± 107.1, P = 0.002) were significantly higher in HF vs. control subjects, indicating chronic tissue changes. Whole-brain comparisons showed increased MD values in HF subjects, including limbic, basal-ganglia, thalamic, solitary tract nucleus, frontal, and cerebellar regions. Brain injury occurs in autonomic and motor control areas, which may contribute to deficient function in HF patients. The chronic tissue changes likely

  12. Prediction of wall friction for fluids at supercritical pressure with CFD models

    International Nuclear Information System (INIS)

    Angelucci, M.; Ambrosini, W.; Forgione, N.

    2011-01-01

    In this paper, the STAR-CCM+ CFD code is used in the attempt to reproduce the values of friction factor observed in experimental data at supercritical pressures at various operating conditions. A short survey of available data and correlations for smooth pipe friction in circular pipes puts the basis for the discussion, reporting observed trends of friction factor in the liquid-like and the gas-like regions and within the transitional region around the pseudo-critical temperature. For smooth pipes, a general decrease of the friction factor in the transitional region is reported, constituting one of the relevant effects to be predicted by the computational fluid-dynamic models. A limited number of low-Reynolds number models is adopted, making use of refined near-wall discretisations as required by the constraint y + < 1 at the wall. In particular, the Lien k-ε and the SST k-ω models are considered. The values of the wall shear stress calculated by the code are then post-processed on the basis of bulk fluid properties to obtain the Fanning and then the Darcy-Weisbach friction factors, basing on their classical definitions. The obtained values are compared with those provided by experimental tests and correlations, finding a reasonable qualitative agreement. Expectedly, the agreement is better in the gas-like and liquid-like regions, where fluid property changes are moderate, than in the transitional region, where the trends provided by available correlations are reproduced only in a qualitative way. (author)

  13. Recruitment of aged donor heart with pharmacological stress echo. A case report

    Directory of Open Access Journals (Sweden)

    Bombardini Tonino

    2006-01-01

    Full Text Available Abstract Background The heart transplant is a treatment of the heart failure, which is not responding to medications, and its efficiency is already proved: unfortunately, organ donation is a limiting step of this life-saving procedure. To counteract heart donor shortage, we should screen aged potential donor hearts for initial cardiomyopathy and functionally significant coronary artery disease. Donors with a history of cardiac disease are generally excluded. Coronary angiography is recommended for most male donors older than 45 years and female donors older than 50 years to evaluate coronary artery stenoses. A simpler way to screen aged potential donor hearts for initial cardiomyopathy and functionally significant coronary artery disease should be stress echocardiography. Case report A marginal donor (A 57 year old woman meeting legal requirements for brain death underwent a transesophageal (TE Dipyridamole stress echo (6 minutes accelerated protocol to rule out moderate or severe heart and coronary artery disease. Wall motion was normal at baseline and at peak stress (WMSI = 1 at baseline and peak stress, without signs of stress inducible ischemia. The pressure/volume ratio was 9.6 mmHg/ml/m2 at baseline, increasing to 14 mmHg/ml/m2 at peak stress, demonstrating absence of latent myocardial dysfunction. The marginal donor heart was transplanted to a recipient "marginal" for co-morbidity ( a 63 year old man with multiple myeloma and cardiac amyloidosis , chronic severe heart failure, NYHA class IV. Postoperative treatment and early immunosuppressant regimen were performed according to standard protocols. The transplanted heart was assessed normal for dimensions and ventricular function at transthoracic (TT echocardiography on post-transplant day 7. Coronary artery disease was ruled out at coronary angiography one month after transplant; left ventriculography showed normal global and segmental LV function of the transplanted heart. Conclusion For

  14. Heart MRI

    Science.gov (United States)

    Magnetic resonance imaging - cardiac; Magnetic resonance imaging - heart; Nuclear magnetic resonance - cardiac; NMR - cardiac; MRI of the heart; Cardiomyopathy - MRI; Heart failure - MRI; Congenital heart disease - MRI

  15. Segmentation of Drosophila Heart in Optical Coherence Microscopy Images Using Convolutional Neural Networks

    OpenAIRE

    Duan, Lian; Qin, Xi; He, Yuanhao; Sang, Xialin; Pan, Jinda; Xu, Tao; Men, Jing; Tanzi, Rudolph E.; Li, Airong; Ma, Yutao; Zhou, Chao

    2018-01-01

    Convolutional neural networks are powerful tools for image segmentation and classification. Here, we use this method to identify and mark the heart region of Drosophila at different developmental stages in the cross-sectional images acquired by a custom optical coherence microscopy (OCM) system. With our well-trained convolutional neural network model, the heart regions through multiple heartbeat cycles can be marked with an intersection over union (IOU) of ~86%. Various morphological and dyn...

  16. Intracranial Vascular Disease Evaluation With Combined Vessel Wall Imaging And Patient Specific Hemodynamics

    Science.gov (United States)

    Samson, Kurt; Mossa-Basha, Mahmud; Yuan, Chun; Canton, Maria De Gador; Aliseda, Alberto

    2017-11-01

    Intracranial vascular pathologies are evaluated with angiography, conventional digital subtraction angiography or non-invasive (MRI, CT). Current techniques present limitations on the resolution with which the vessel wall characteristics can be measured, presenting a major challenge to differential diagnostic of cerebral vasculopathies. A new combined approach is presented that incorporates patient-specific image-based CFD models with intracranial vessel-wall MRI (VWMRI). Comparisons of the VWMRI measurements, evaluated for the presence of wall enhancement and thin-walled regions, against CFD metrics such as wall shear stress (WSS), and oscillatory shear index (OSI) are used to understand how the new imaging technique developed can predict the influence of hemodynamics on the deterioration of the aneurysmal wall, leading to rupture. Additionally, histology of each resected aneurysm, evaluated for inflammatory infiltration and wall thickness features, is used to validate the analysis from VWMRI and CFD. This data presents a solid foundation on which to build a new framework for combined VWMRI-CFD to predict unstable wall changes in unruptured intracranial aneurysms, and support clinical monitoring and intervention decisions.

  17. Liquid Wall Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  18. Rising damp in building walls: the wall base ventilation system

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, A.S.; Delgado, J.M.P.Q.; Freitas, V.P. de [Faculdade de Engenharia da Universidade do Porto, Laboratorio de Fisica das Construcoes (LFC), Departamento de Engenharia Civil, Porto (Portugal)

    2012-12-15

    This work intends to validate a new system for treating rising damp in historic buildings walls. The results of laboratory experiments show that an efficient way of treating rising damp is by ventilating the wall base, using the HUMIVENT technique. The analytical model presented describes very well the observed features of rising damp in walls, verified by laboratory tests, who contributed for a simple sizing of the wall base ventilation system that will be implemented in historic buildings. (orig.)

  19. Heart Health - Heart Disease: Symptoms, Diagnosis, Treatment

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health Heart Disease: Symptoms, Diagnosis, Treatment Past Issues / Winter 2009 ... of this page please turn Javascript on. Most heart attacks happen when a clot in the coronary ...

  20. Cardiac dose reduction with deep inspiration breath hold for left-sided breast cancer radiotherapy patients with and without regional nodal irradiation

    International Nuclear Information System (INIS)

    Yeung, Rosanna; Conroy, Leigh; Long, Karen; Walrath, Daphne; Li, Haocheng; Smith, Wendy; Hudson, Alana; Phan, Tien

    2015-01-01

    Deep inspiration breath hold (DIBH) reduces heart and left anterior descending artery (LAD) dose during left-sided breast radiation therapy (RT); however there is limited information about which patients derive the most benefit from DIBH. The primary objective of this study was to determine which patients benefit the most from DIBH by comparing percent reduction in mean cardiac dose conferred by DIBH for patients treated with whole breast RT ± boost (WBRT) versus those receiving breast/chest wall plus regional nodal irradiation, including internal mammary chain (IMC) nodes (B/CWRT + RNI) using a modified wide tangent technique. A secondary objective was to determine if DIBH was required to meet a proposed heart dose constraint of D mean < 4 Gy in these two cohorts. Twenty consecutive patients underwent CT simulation both free breathing (FB) and DIBH. Patients were grouped into two cohorts: WBRT (n = 11) and B/CWRT + RNI (n = 9). 3D-conformal plans were developed and FB was compared to DIBH for each cohort using Wilcoxon signed-rank tests for continuous variables and McNemar’s test for discrete variables. The percent relative reduction conferred by DIBH in mean heart and LAD dose, as well as lung V 20 were compared between the two cohorts using Wilcox rank-sum testing. The significance level was set at 0.05 with Bonferroni correction for multiple testing. All patients had comparable target coverage on DIBH and FB. DIBH statistically significantly reduced mean heart and LAD dose for both cohorts. Percent reduction in mean heart and LAD dose with DIBH was significantly larger in the B/CWRT + RNI cohort compared to WBRT group (relative reduction in mean heart and LAD dose: 55.9 % and 72.1 % versus 29.2 % and 43.5 %, p < 0.02). All patients in the WBRT group and five patients (56 %) in the B/CWBRT + RNI group met heart D mean <4 Gy with FB. All patients met this constraint with DIBH. All patients receiving WBRT met D mean Heart < 4 Gy on FB, while only slightly over

  1. Fast wall of thermonuclear device

    International Nuclear Information System (INIS)

    Kitamura, Kazunori.

    1990-01-01

    A protruding molten metal reservoir is disposed to a sealing vessel embedded in the armour tile of fast walls, and molten metal of low melting point such as tin, lead or alloy thereof is filled in the sealing vessel. The volume of the molten metal reservoir is determined such that the surface level of the molten metal is kept within the molten metal reservoir even when the sealed low melting point metal is solidified at room temperature. When the temperature is lowered during plasma interruption period and the sealed low melting molten metal is solidified to reduce the volume, most of the molten metal reservoir regioin constitutes a vacuum gap. However, the inner wall of the sealing vessel other than the molten metal reservior region can be kept into contact with the sealed metal. Accordingly, the temperature and the sublimation loss of the armour tile can be kept low even upon plasma heat application. (I.N.)

  2. Lattice Boltzmann simulations for wall-flow dynamics in porous ceramic diesel particulate filters

    Science.gov (United States)

    Lee, Da Young; Lee, Gi Wook; Yoon, Kyu; Chun, Byoungjin; Jung, Hyun Wook

    2018-01-01

    Flows through porous filter walls of wall-flow diesel particulate filter are investigated using the lattice Boltzmann method (LBM). The microscopic model of the realistic filter wall is represented by randomly overlapped arrays of solid spheres. The LB simulation results are first validated by comparison to those from previous hydrodynamic theories and constitutive models for flows in porous media with simple regular and random solid-wall configurations. We demonstrate that the newly designed randomly overlapped array structures of porous walls allow reliable and accurate simulations for the porous wall-flow dynamics in a wide range of solid volume fractions from 0.01 to about 0.8, which is beyond the maximum random packing limit of 0.625. The permeable performance of porous media is scrutinized by changing the solid volume fraction and particle Reynolds number using Darcy's law and Forchheimer's extension in the laminar flow region.

  3. Heart Health: The Heart Truth Campaign 2009

    Science.gov (United States)

    ... Bar Home Current Issue Past Issues Cover Story Heart Health The Heart Truth Campaign 2009 Past Issues / Winter 2009 Table ... one of the celebrities supporting this year's The Heart Truth campaign. Both R&B singer Ashanti (center) ...

  4. Women's Heart Disease: Heart Disease Risk Factors

    Science.gov (United States)

    ... this page please turn JavaScript on. Feature: Women's Heart Disease Heart Disease Risk Factors Past Issues / Winter 2014 Table ... or habits may raise your risk for coronary heart disease (CHD). These conditions are known as risk ...

  5. Active particle control experiments and critical particle flux discriminating between the wall pumping and fuelling in the compact plasma wall interaction device CPD spherical tokamak

    International Nuclear Information System (INIS)

    Zushi, H.; Sakamoto, M.; Yoshinaga, T.; Higashizono, Y.; Hanada, K.; Yoshida, N.; Tokunaga, K.; Kawasaki, S.; Sato, K. N.; Nakamura, K.; Idei, H.; Hirooka, Y.; Bhattacharyay, R.; Okamoto, K.; Miyazaki, T.; Honma, H.; Nakashima, Y.; Nishino, N.; Kado, S.; Shikama, T.

    2009-01-01

    Two approaches associated with wall recycling have been performed in a small spherical tokamak device CPD (compact plasma wall interaction experimental device), that is, (1) demonstration of active particle recycling control, namely, 'active wall pumping' using a rotating poloidal limiter whose surface is continuously gettered by lithium and (2) a basic study of the key parameters which discriminates between 'wall pumping and fuelling'. For the former, active control of 'wall pumping' has been demonstrated during 50 kW RF current drive discharges whose pulse length is typically ∼300 ms. Although the rotating limiter is located at the outer board, as soon as the rotating drum is gettered with lithium, hydrogen recycling measured with H α spectroscopy decreases by about a factor of 3 not only near the limiter but also in the centre stack region. Also, the oxygen impurity level measured with O II spectroscopy is reduced by about a factor of 3. As a consequence of the reduced recycling and impurity level, RF driven current has nearly doubled at the same vertical magnetic field. For the latter, global plasma wall interaction with plasma facing components in the vessel is studied in a simple torus produced by electron cyclotron waves with I p -4 to ∼0.1 x 10 -4 Torr during the experimental campaign (∼3000 shots). In the wall pumping pressure range the wall pumping fraction is reduced with increasing surface temperature up to 150 deg. C.

  6. Lung and heart pathology in fatal drug addiction. A consecutive autopsy study.

    Science.gov (United States)

    Kringsholm, B; Christoffersen, P

    1987-01-01

    Lung and heart sections from 33 drug addicts submitted for medico-legal autopsy at the Institute of Forensic Medicine in Copenhagen were studied together with tissue sections from 20 'normal' persons. In the drug addict cases focal bleedings in lung tissue were found in 94%, signs of earlier bleedings, haemosiderin containing histiocytes, were seen in 91%, and focal fibrosis in 46%. The bleeding episodes may be due to hypoxia in connection with heroin intake. In 94% of the drug addicts birefringent material in lung tissue was demonstrated, in 58% in granulomas and giant cells, in 27% in giant cells only and in 9% in isolated histiocytes. The material was localized in the wall of pulmonar arteries and/or in the interstitial tissue, undoubtedly depending on the duration of the abuse. In 18% angiothrombosis was seen, in all cases granulomas/giant cells were observed in the wall of the vessel concerned. The results indicate periodical intravenous injection of dissolved tablets in addition to heroin. Histological signs of pulmonary hypertension were not seen, possibly due to the fact that abuse of central stimulants is very rare in Denmark. Regarding heart alterations no significant differences were demonstrated between drug addicts and controls. The only note-worthy finding was focal infiltration of lymphocytes in the atrio-ventricular bundle in two drug addicts, the meaning of which is uncertain.

  7. The effect of wall temperature distribution on streaks in compressible turbulent boundary layer

    Science.gov (United States)

    Zhang, Zhao; Tao, Yang; Xiong, Neng; Qian, Fengxue

    2018-05-01

    The thermal boundary condition at wall is very important for the compressible flow due to the coupling of the energy equation, and a lot of research works about it were carried out in past decades. In most of these works, the wall was assumed as adiabatic or uniform isothermal surface; the flow over a thermal wall with some special temperature distribution was seldom studied. Lagha studied the effect of uniform isothermal wall on the streaks, and pointed out that higher the wall temperature is, the longer the streak (POF, 2011, 23, 015106). So, we designed streamwise stripes of wall temperature distribution on the compressible turbulent boundary layer at Mach 3.0 to learn the effect on the streaks by means of direct numerical simulation in this paper. The mean wall temperature is equal to the adiabatic case approximately, and the width of the temperature stripes is in the same order as the width of the streaks. The streak patterns in near-wall region with different temperature stripes are shown in the paper. Moreover, we find that there is a reduction of friction velocity with the wall temperature stripes when compared with the adiabatic case.

  8. HEART FAILURE – KEEPING STEP WITH THE PROGRESS

    Directory of Open Access Journals (Sweden)

    Camelia Diaconu

    2018-06-01

    countries across North America (NA, Central and South America (CSA, Western (WE and Eastern Europe (EE, the Eastern Mediterranean and Africa (EMA, South East Asia (SEA and the Western Pacific (WP, under the study co-chairs, Prof. Gerasimos Filippatos (Greece and Prof. Mihai Gheorghiade (USA. Inter-regional differences in the hospital entry point, comorbidities and precipitants have been observed. Ischemia was a common precipitant in SEA, WP and EMA, whereas non-adherence to diet and medication was more common in NA. There have been also observed differences regarding the treatment, especially in time to initial intravenous therapy. Patients in NA have significantly longer time to first therapy, compared with other regions; this may impact the symptoms, because the sooner the IV therapies are delivered, the sooner symptoms will improve. There are differences regarding the implementation of international heart failure guidelines, which may influence the patients’ outcomes. Researchers from the Institute of Molecular Biotechnology at the Vienna BioCenter have studied the first systems for heart regeneration following complex heart attacks in mammals. In vivo neonatal models showed that, after a heart attack, mice underwent total repair of cardiac injury. This type of repair had been encountered previously in fish, but not in mammals. The researchers set up now genetic systems to identify the molecular signals that mediate this regeneration of the heart. Biotechnologies may become the future of the heart failure treatment.

  9. Quantitative description of the 3D regional mechanics of the left atrium using cardiac magnetic resonance imaging

    International Nuclear Information System (INIS)

    Kuklik, P; Molaee, P; Ganesan, A N; Brooks, A G; Worthley, S G; Sanders, P; Podziemski, P

    2014-01-01

    The left atrium (LA) plays an important role in the maintenance of hemodynamic and electrical stability of the heart. One of the conditions altering the atrial mechanical function is atrial fibrillation (AF), leading to an increased thromboembolic risk due to impaired mechanical function. Preserving the regions of the LA that contribute the greatest to atrial mechanical function during curative strategies for AF is important. The purpose of this study is to introduce a novel method of regional assessment of mechanical function of the LA. We used cardiac MRI to reconstruct the 3D geometry of the LA in nine control and nine patients with paroxysmal atrial fibrillation (PAF). Regional mechanical function of the LA in pre-defined segments of the atrium was calculated using regional ejection fraction and wall velocity. We found significantly greater mechanical function in anterior, septal and lateral segments as opposed to roof and posterior segments, as well as a significant decrease of mechanical function in the PAF group. We suggest that in order to minimize the impact of the AF treatment on global atrial mechanical function, damage related to therapeutic intervention, such as catheter ablation, in those areas should be minimized. (paper)

  10. Aortic valve-sparing operation after correction of heart displacement due to pectus excavatum using Nuss procedure in a Marfan syndrome patient.

    Science.gov (United States)

    Fukunaga, Naoto; Yuzaki, Mitsuru; Hamakawa, Hiroshi; Nasu, Michihiro; Takahashi, Yutaka; Okada, Yukikatsu

    2012-01-01

    Cardiovascular surgery in the setting of chest wall deformities is a clinical challenge. Pectus excavatum, for example, can cause heart displacement to the left thoracic cavity, following the poor operative field. This report highlights a case in which a successful aortic valve-sparing operation via conventional median sternotomy after correction of the heart displacement due to pectus excavatum using Nuss procedure in Marfan syndrome. This technique can be one surgical option in Marfan syndrome patients with pectus excavatum and thoracic aortic aneurysm under close follow up.

  11. The effect of load-controlled bending load on the failure pressure of wall-thinned pipe elbows

    International Nuclear Information System (INIS)

    Kim, Jin Weon; Yoon, Min Soo; Park, Chi Yong

    2013-01-01

    Highlights: • We evaluated bending load effect on the failure pressure of wall-thinned pipe elbows. • Burst tests were conducted on real-scale elbow specimens with local wall thinning. • The tests were performed under combined pressure and load-controlled bending. • Load-controlled bending reduced the failure pressure of wall-thinned elbows. • Bending load effect was significant for opening-mode and intrados wall-thinning case. - Abstract: In this research, burst tests were conducted on real-scale elbow specimens, each with an artificial local wall-thinning defect, under combined internal pressure and constant in-plane bending load, as well as under simple internal pressure, to evaluate the effect of load-controlled bending load on the failure pressure of locally wall-thinned pipe elbows. Ninety-degree, 65A Schedule 80 elbows, with wall-thinning defects in the intrados and extrados, were used as specimens. The bending loads were in-plane opening- and closing-mode bending, applied in load-control mode. The results clearly indicated that a load-controlled in-plane bending load reduced the failure pressure of wall-thinned pipe elbows, in contrast to observations previously made under displacement-controlled bending conditions. The effect of the bending load was more significant for opening-mode than for closing-mode bending, regardless of the wall-thinning location in the elbow. Also, the effect was greater when the wall-thinning defect was located in the intrados region of the elbow, rather than the extrados region. Existing models that have been proposed to evaluate the failure of wall-thinned elbows under simple internal pressure conservatively predicted the failure pressure of elbows subjected to a combined internal pressure and load-controlled bending load

  12. Bridging the Gap, Facing the Challenge—the 26th Great Wall International Congress of Cardiology (GW-ICC)

    OpenAIRE

    Zhang, Yingmei; Ren, Jun

    2016-01-01

    The joint venue of the 26th Great Wall International Congress of Cardiology (GW-ICC) & Asia Pacific Heart Congress 2015 (APHC 2015) & International Congress Cardiovascular Prevention and Rehabilitation 2015 (ICCPR 2015) were held from October 29 to November 01, 2015 at the China National Convention Center (CNCC), Beijing, China. This year’s conference focused on cardiovascular disease prevention, health promotion, education and training, as well as disease management and rehabilitation.

  13. Right heart ejection fraction, ventricular volumes, and left to right cardiac shunt measurements with a conventional Anger camera in congenital heart disease

    International Nuclear Information System (INIS)

    Cook, S.A.; Go, R.T.; MacIntyre, W.J.; Moodie, D.S.; Houser, T.S.; Ceimo, J.; Underwood, D.; Yiannikas, J.

    1982-01-01

    The object of this investigation was to demonstrate that a conventional Anger camera can be used for measurement of right heart ejection fraction, ventricular volumes and left to right shunts in routine clinical determinations. The automatic selection of chamber and lung regions, the recirculation subtraction of recirculation, and the filtering of the right heart ejection fraction dilution curves are all done entirely without operator intervention. Thus, this entire evaluation has been incorporated into the routine procedures of patient care

  14. Reynolds number invariance of the structure inclination angle in wall turbulence.

    Science.gov (United States)

    Marusic, Ivan; Heuer, Weston D C

    2007-09-14

    Cross correlations of the fluctuating wall-shear stress and the streamwise velocity in the logarithmic region of turbulent boundary layers are reported over 3 orders of magnitude change in Reynolds number. These results are obtained using hot-film and hot-wire anemometry in a wind tunnel facility, and sonic anemometers and a purpose-built wall-shear stress sensor in the near-neutral atmospheric surface layer on the salt flats of Utah's western desert. The direct measurement of fluctuating wall-shear stress in the atmospheric surface layer has not been available before. Structure inclination angles are inferred from the cross correlation results and are found to be invariant over the large range of Reynolds number. The findings justify the prior use of low Reynolds number experiments for obtaining structure angles for near-wall models in the large-eddy simulation of atmospheric surface layer flows.

  15. External heart deformities in passerine birds exposed to environmental mixtures of polychlorinated biphenyls during development.

    Science.gov (United States)

    DeWitt, Jamie C; Millsap, Deborah S; Yeager, Ronnie L; Heise, Steve S; Sparks, Daniel W; Henshel, Diane S

    2006-02-01

    Necropsy-observable cardiac deformities were evaluated from 283 nestling passerines collected from one reference site and five polychlorinated biphenyl (PCB)-contaminated sites around Bloomington and Bedford, Indiana, USA. Hearts were weighed and assessed on relative scales in three dimensions (height, length, and width) and for externally visible deformities. Heart weights normalized to body weight (heart somatic index) were decreased significantly at the more contaminated sites in both house wren (Troglodytes aedon) and tree swallow (Tachycineta bicolor). Heart somatic indices significantly correlated with log PCB concentrations in Carolina chickadee (Parus carolinesis) and tree swallow and with log 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent values in tree swallow alone. Ventricular length was increased significantly in eastern bluebirds (Sialia sialis) and decreased significantly in Carolina chickadee and tree swallow from contaminated sites versus the reference site. Heart length regressed significantly against the log PCB concentrations (Carolina chickadee and tree swallow) or the square of the PCB concentrations (red-winged blackbird [Agelaius phoeniceus]) in a sibling bird. The deformities that were observed most at the contaminated sites included abnormal tips (pointed, rounded, or flattened), center rolls, macro- and microsurface roughness, ventricular indentations on the ventral or dorsal surface, lateral ventricular notches, visibly thin ventricular walls, and changes in overall heart shape. A pooled heart deformity index regressed significantly against the logged contaminant concentrations for all species except red-winged blackbird. These results indicate that developmental changes in heart morphometrics and shape abnormalities are quantifiable and may be sensitive and useful indicators of PCB-related developmental impacts across many avian species.

  16. 201Tl-redistribution analysis in early and delayed myocordial scintigrams of patients with coronary heart disease (CHD)

    International Nuclear Information System (INIS)

    Hoer, G.; Sebening, H.; Sauer, E.; Dressler, J.; Lutilsky, L.; Wagner-Manslau, C.; Bofilias, I.; Technische Univ. Muenchen

    1979-01-01

    Scans were performed on 8 healthy subjects and 25 with coronary heart disease proven by angiography and ventriculography including 6 with previous myocardial infarction at rest, exercise, and 1 and 2 h after exercise. Data were collected by a gamma camera interfaced to a data collection system. In healthy subjects 201 Tl distribution was homogeneous at rest and after exercise, the count rate ranging between 100% - as set in the region of maximum - and 80% over other regions of myocardium. In 19 patients with coronary heart disease it was uniform only at rest; 6 patients with previous myocardial infarction had locally diminished 201 Tl uptake even at rest. In patients with coronary heart disease without previous myocardial infarction, scans made immediately after exercise showed significant 201 Tl hypofixation in region of minimum, the count rate of which was less than 80% of the count rate as determined over region of maximum, 201 Tl uptake. Scans made 1 and 2 h after exercise had filling-in of 201 Tl within the region of minimum the count rate of which returned to the normal range of at least 80% of the count rate measured over region of maximum uptake. This return to resting distribution was called 201 Tl redistribution. Six patients with coronary heart disease and previous myocardial infarction had 201 Tl defects larger after exercise than at rest, without redistribution being observed. Redistribution in late postexercise scans is a sign of reversible ischemia in coronary heart disease. Scans at rest may be omitted in coronary heart disease, because transient ischemia is undetectable, unless spontaneous angina occurs during scan procedure. (orig.) [de

  17. Aging influences multiple indices of oxidative stress in the heart of the Fischer 344/NNia x Brown Norway/BiNia rat.

    Science.gov (United States)

    Asano, Shinichi; Rice, Kevin M; Kakarla, Sunil; Katta, Anjaiah; Desai, Devashish H; Walker, Ernest M; Wehner, Paulette; Blough, Eric R

    2007-01-01

    We report the influence of aging on multiple markers of oxidative-nitrosative stress in the heart of adult (6-month), aged (30-month) and very aged (36-month) Fischer 344/NNiaHSd x Brown Norway/BiNia (F344/NXBN) rats. Compared to adult (6-month) hearts, indices of oxidative (superoxide anion [O2*-], 4-hydroxy-2-nonenal [4-HNE]) and nitrosative (protein nitrotyrosylation) stress were 34.1 +/- 28.1%, 186 +/- 28.1% and 94 +/- 5.8% higher, respectively, in 36-month hearts and these findings were highly correlated with increases in left ventricular wall thickness (r > 0.669; r > 0.710 and P lead to age-associated alterations in cardiac oxidative stress.

  18. The Aspergillus niger MADS-box transcription factor RlmA is required for cell wall reinforcement in response to cell wall stress.

    NARCIS (Netherlands)

    Damveld, R.A.; Arentshorst, M.; Franken, A.; Vankuyk, P.A.; Klis, F.M.; van den Hondel, C.A.; Ram, A.F.

    2005-01-01

    In Aspergillus niger, the genes coding for glutamine:fructose-6-phosphate amidotransferase (gfaA) and ¿-1,3-glucan synthase (agsA) are induced in response to cell wall stress. In silico analysis of the promoter region of the two genes revealed the presence of putative DNA binding sites for

  19. Measurement of wall thickness with electrodynamic test heads

    International Nuclear Information System (INIS)

    Koch, R.; Maurer, A.

    1993-01-01

    Starting from the boundary conditions fixed by the physical properties of the electromagnetic/acoustic conversion and the operating limits which result from these for the sensors used, the use of electro-dynamic ultrasonic transducers for measuring wall thickness and double checks in plants for automatic production inspection and production control is shown. The sensor itself is the heart of a test system, but only the equipment and plant concepts surrounding the sensor make economic solution of the test problem possible. The quality of the signals which are supplied by a sensor, determines the quality of a test system. This can only be achieved by optimising all parts of a complex automatic test rig, such as the test head, mechanics, electronics and evaluation for the