NASA-Ames Summer High School Apprenticeship Research Program (SHARP)

Science.gov (United States)

Powell, P.

1983-01-01

The function of SHARP is to recognize high school juniors who have demonstrated unusually high promise for sucess in mathemtics and science. Twenty academically talented students who will be seniors in high school in September were chosen to participate in SHARP 83. Mentors were selected to provide students with first-hand experiences in a research and development environment in order that each student might try out his or her tentative professional career choice. Some special features of SHARP included field trips to private industries doing similar and related research, special lectures on topics of research here at ARC, individual and group counseling sessions, written research papers and oral reports, and primarily the opportunity to be exposed to the present frontiers in space exploration and research. The long-range goal of SHARP is to contribute to the future recruitment of needed scientists and engineers. This final report is summary of all the phases of the planning and implemenation of the 1983 Summer High School Apprenticeship Research Program (SHARP).

Improved detection of chronic myocardial infarction with Fourier amplitude and phase imaging in two projections

International Nuclear Information System (INIS)

Akins, E.W.; Scott, E.A.; Williams, C.M.

1987-01-01

Twenty-seven patients with 33 chronic myocaridal infarctions underwent MR imaging and radionuclide ventriculography at rest. The radionuclide ventriculographs, in left anterior oblique (LAO) and left posterior oblique (LPO) projections, were analyzed by two independent observers by visual inspection and combined Fourier-transformed amplitude and phase imaging. Only 15 (45%) of the 33 infarctions were detected by visual inspection, but 21 (64%) were detected on the LAO Fourier-transformed images along. Thirty (91%) were detected by using both LAO and LPO Fourier-transformed images. On MR imaging, 28 (85%) of the myocardial infarctions appeared as areas of focal wall thinning. Combined Fourier-transformed amplitude and phase imaging in both LAO and LPO views discloses more myocardial infarctions than visual inspection or LAO Fourier-transformed images alone because inferior infarctions, which are frequently missed in the LAO view, are easily seen in the LPO view

Assessment of myocardial viability using multidetector computed tomography in patients with reperfused acute myocardial infarction

International Nuclear Information System (INIS)

Kim, T.; Choi, B.J.; Kang, D.K.; Sun, J.S.

2012-01-01

Aim: To assess the prognostic value of 64-section multidetector computed tomography (MDCT) to predict follow-up myocardial dysfunction and functional recovery after reperfusion therapy in patients with acute myocardial infarction (MI) as defined by echocardiography. Materials and methods: After reperfusion therapy for acute MI, 71 patients underwent two-phase contrast-enhanced MDCT and follow-up echocardiography. MDCT findings were compared with echocardiographic findings using kappa statistics. The areas under the receiver operating characteristic curves (AUCs) and the odds ratios (ORs) of early perfusion defects (EPD), delayed enhancement (DE), and residual perfusion defects (RPD) for predicting follow-up myocardial dysfunction and functional recovery were calculated on a segmental basis. Results: The presence of transmural EPD (EPD TM ) or RPD showed good agreement (k = 0.611 and 0.658, respectively) with follow-up myocardial dysfunction, while subendocardial EPD (EPD sub ) or subendocardial DE (DE sub ) showed fair agreement with follow-up myocardial dysfunction (k = 0.235 and 0.234, respectively). The AUC of RPD (0.796) was superior (p TM (0.761) and DE TM (0.771). The presence of EPD TM , DE TM , and RPD were significant, independent positive predictors of follow-up myocardial dysfunction (OR = 6.4, 1.9, and 9.8, respectively). EPD TM was a significant, independent negative predictor of myocardial functional recovery (OR = 0.13). Conclusion: Abnormal myocardial attenuation on two-phase MDCT after reperfusion therapy may provide promising information regarding myocardial viability in patients with acute MI.

SHARP User Manual

Energy Technology Data Exchange (ETDEWEB)

Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Thomas, J. W. [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States); Solberg, Jerome [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-03-31

SHARP is an advanced modeling and simulation toolkit for the analysis of nuclear reactors. It is comprised of several components including physical modeling tools, tools to integrate the physics codes for multi-physics analyses, and a set of tools to couple the codes within the MOAB framework. Physics modules currently include the neutronics code PROTEUS, the thermal-hydraulics code Nek5000, and the structural mechanics code Diablo. This manual focuses on performing multi-physics calculations with the SHARP ToolKit. Manuals for the three individual physics modules are available with the SHARP distribution to help the user to either carry out the primary multi-physics calculation with basic knowledge or perform further advanced development with in-depth knowledge of these codes. This manual provides step-by-step instructions on employing SHARP, including how to download and install the code, how to build the drivers for a test case, how to perform a calculation and how to visualize the results. Since SHARP has some specific library and environment dependencies, it is highly recommended that the user read this manual prior to installing SHARP. Verification tests cases are included to check proper installation of each module. It is suggested that the new user should first follow the step-by-step instructions provided for a test problem in this manual to understand the basic procedure of using SHARP before using SHARP for his/her own analysis. Both reference output and scripts are provided along with the test cases in order to verify correct installation and execution of the SHARP package. At the end of this manual, detailed instructions are provided on how to create a new test case so that user can perform novel multi-physics calculations with SHARP. Frequently asked questions are listed at the end of this manual to help the user to troubleshoot issues.

SHARP User Manual

International Nuclear Information System (INIS)

Yu, Y. Q.; Shemon, E. R.; Thomas, J. W.; Mahadevan, Vijay S.; Rahaman, Ronald O.; Solberg, Jerome

2016-01-01

SHARP is an advanced modeling and simulation toolkit for the analysis of nuclear reactors. It is comprised of several components including physical modeling tools, tools to integrate the physics codes for multi-physics analyses, and a set of tools to couple the codes within the MOAB framework. Physics modules currently include the neutronics code PROTEUS, the thermal-hydraulics code Nek5000, and the structural mechanics code Diablo. This manual focuses on performing multi-physics calculations with the SHARP ToolKit. Manuals for the three individual physics modules are available with the SHARP distribution to help the user to either carry out the primary multi-physics calculation with basic knowledge or perform further advanced development with in-depth knowledge of these codes. This manual provides step-by-step instructions on employing SHARP, including how to download and install the code, how to build the drivers for a test case, how to perform a calculation and how to visualize the results. Since SHARP has some specific library and environment dependencies, it is highly recommended that the user read this manual prior to installing SHARP. Verification tests cases are included to check proper installation of each module. It is suggested that the new user should first follow the step-by-step instructions provided for a test problem in this manual to understand the basic procedure of using SHARP before using SHARP for his/her own analysis. Both reference output and scripts are provided along with the test cases in order to verify correct installation and execution of the SHARP package. At the end of this manual, detailed instructions are provided on how to create a new test case so that user can perform novel multi-physics calculations with SHARP. Frequently asked questions are listed at the end of this manual to help the user to troubleshoot issues.

Sharpening Sharpe Ratios

OpenAIRE

William N. Goetzmann; Jonathan E. Ingersoll Jr.; Matthew I. Spiegel; Ivo Welch

2002-01-01

It is now well known that the Sharpe ratio and other related reward-to-risk measures may be manipulated with option-like strategies. In this paper we derive the general conditions for achieving the maximum expected Sharpe ratio. We derive static rules for achieving the maximum Sharpe ratio with two or more options, as well as a continuum of derivative contracts. The optimal strategy has a truncated right tail and a fat left tail. We also derive dynamic rules for increasing the Sharpe ratio. O...

Sharp and the Jules Verne Launcher

Science.gov (United States)

Hunter, John; Cartland, Harry

1996-03-01

Lawrence Livermore National Laboratory (LLNL) has built the worlds largest hydrogen gas gun called SHARP, (Super High Altitude Research Project). Originally designed to launch 5 kg to a 450 km altitude, SHARP is configured horizontally at Site 300 in Tracy, California. SHARP is successfully delivering 5 kg scramjets at Mach 9 in aerophysics tests. Some of the results of the scramjet tests are enlightening and are presented insofar as they are relevant to future launches into space. Using a light gas gun to launch payloads into orbit has been analyzed. We look at LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), and LO (Lunar Orbit). We present a conceptual design for a large light gas gun called the Jules Verne Launcher (JVL). The JVL can deliver 3.3 metric tons to a 500 km low earth orbit. We anticipate one launch per day. We present the history of light gas guns, the SHARP design and performance, and the JVL design. Another section is devoted to the vehicle environment and resultant design. Lastly, we present a cost analysis. Our results indicated that the JVL will be able to deliver 1000 metric tons of payload to LEO yearly. The cost will be 5% of the best US rocket delivery cost. This technology will enable the next phase of man's exploration of space.

The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by 15O-water-PET

International Nuclear Information System (INIS)

Tsukagoshi, Joichi

1994-01-01

The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by 15 O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with 15 O-water even in the absence of metabolic imaging. (author)

Value of the Doppler index of myocardial performance in the early phase of acute myocardial infarction

DEFF Research Database (Denmark)

Poulsen, S H; Jensen, S E; Tei, C

2000-01-01

Prospective assessment of a nongeometric Doppler-derived index of combined systolic and diastolic myocardial performance was performed in 64 patients with acute myocardial infarction (MI) within 1 hour after their arrival to the hospital and in 39 age-matched healthy subjects. The index is defined...

Thallium-201 myocardial imaging in acute-myocardial infarction

International Nuclear Information System (INIS)

Wackers, F.J.Th.; Lie, K.I.; Sokole, E.B.; Wellens, H.J.J.; Samson, G.; Schoot, J.B. van der

1980-01-01

Thallium-201 scintigraphy has proven to be an early and highly sensitive technique to detect myocardial perfusion abnormalities in patients with acute myocardial infarction. During the early phase of acute myocardial infarction, patients may be hemodynamically and electrically unstable. Therefore, scintigraphy is performed preferably at the bed side in the Coronary Care Unit using a mobile gamma camera. Additionally, in order to shorten imaging time in these often critically ill patients, the authors recommend injecting no less than 2 mCi of 201 Tl. Using this dosage, the imaging time per view will be approximately five minutes. Routinely, three views are taken: the first view is a supine 45 0 left-anterior-oblique view, followed by a supine anterior view and finally a left-lateral view, the latter with the patient turned on the right side. (Auth.)

Late-phase MSCT in the different stages of myocardial infarction: animal experiments

International Nuclear Information System (INIS)

Mahnken, Andreas H.; Bruners, Philipp; Kinzel, Sylvia; Katoh, Marcus; Muehlenbruch, Georg; Guenther, Rolf W.; Wildberger, Joachim E.

2007-01-01

The purpose of this study was to intraindividually evaluate myocardial late enhancement on multislice spiral computed tomography (MSCT) for the assessment of the different stages of myocardial infarction (MI) in comparison with magnetic resonance (MR) imaging. Reperfused MI was successfully induced in seven pigs. Delayed enhancement MR imaging and late-phase MSCT were performed on day 0 as well as 7, 28 and 90 days after the procedure. The pigs were sacrificed, and 2,3,5-triphenyltetrazolin-chloride (TTC) staining was acquired. MI size was compared between the different imaging techniques and over time applying Bland-Altman plots and multivariate analysis with repeated measures. On day 0 the mean MI size was 23.7 ± 11.8% of the left ventricular area on MSCT and 24.5 ± 10.6% on MR imaging. On day 90 infarct sizes decreased significantly to 16.9 ± 8.4% and 18.9 ± 8.0%, respectively (P 0.0019). On TTC staining the size of MI was 16.8 ± 8.2%. Bland-Altman plots showed a good agreement between MSCT and MR imaging with mean deviations ranging from -3.4% to -1.9%. No significant difference between MSCT and MR imaging was found. Myocardial late enhancement on MSCT correlates well with delayed enhancement MR imaging during the different stages of MI and allows for reliable assessment of reperfused MI during acute, subacute and chronic stages. (orig.)

SHARP Multiphysics Tutorials

Energy Technology Data Exchange (ETDEWEB)

Yu, Y. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States); Mahadevan, Vijay S. [Argonne National Lab. (ANL), Argonne, IL (United States); Rahaman, Ronald O. [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-02-29

SHARP, developed under the NEAMS Reactor Product Line, is an advanced modeling and simulation toolkit for the analysis of advanced nuclear reactors. SHARP is comprised of three physics modules currently including neutronics, thermal hydraulics, and structural mechanics. SHARP empowers designers to produce accurate results for modeling physical phenomena that have been identified as important for nuclear reactor analysis. SHARP can use existing physics codes and take advantage of existing infrastructure capabilities in the MOAB framework and the coupling driver/solver library, the Coupled Physics Environment (CouPE), which utilizes the widely used, scalable PETSc library. This report aims at identifying the coupled-physics simulation capability of SHARP by introducing the demonstration example called sahex in advance of the SHARP release expected by Mar 2016. sahex consists of 6 fuel pins with cladding, 1 control rod, sodium coolant and an outer duct wall that encloses all the other components. This example is carefully chosen to demonstrate the proof of concept for solving more complex demonstration examples such as EBR II assembly and ABTR full core. The workflow of preparing the input files, running the case and analyzing the results is demonstrated in this report. Moreover, an extension of the sahex model called sahex_core, which adds six homogenized neighboring assemblies to the full heterogeneous sahex model, is presented to test homogenization capabilities in both Nek5000 and PROTEUS. Some primary information on the configuration and build aspects for the SHARP toolkit, which includes capability to auto-download dependencies and configure/install with optimal flags in an architecture-aware fashion, is also covered by this report. A step-by-step instruction is provided to help users to create their cases. Details on these processes will be provided in the SHARP user manual that will accompany the first release.

SHARP Multiphysics Tutorials

International Nuclear Information System (INIS)

Yu, Y. Q.; Shemon, E. R.; Mahadevan, Vijay S.; Rahaman, Ronald O.

2016-01-01

SHARP, developed under the NEAMS Reactor Product Line, is an advanced modeling and simulation toolkit for the analysis of advanced nuclear reactors. SHARP is comprised of three physics modules currently including neutronics, thermal hydraulics, and structural mechanics. SHARP empowers designers to produce accurate results for modeling physical phenomena that have been identified as important for nuclear reactor analysis. SHARP can use existing physics codes and take advantage of existing infrastructure capabilities in the MOAB framework and the coupling driver/solver library, the Coupled Physics Environment (CouPE), which utilizes the widely used, scalable PETSc library. This report aims at identifying the coupled-physics simulation capability of SHARP by introducing the demonstration example called sahex in advance of the SHARP release expected by Mar 2016. sahex consists of 6 fuel pins with cladding, 1 control rod, sodium coolant and an outer duct wall that encloses all the other components. This example is carefully chosen to demonstrate the proof of concept for solving more complex demonstration examples such as EBR II assembly and ABTR full core. The workflow of preparing the input files, running the case and analyzing the results is demonstrated in this report. Moreover, an extension of the sahex model called sahex c ore, which adds six homogenized neighboring assemblies to the full heterogeneous sahex model, is presented to test homogenization capabilities in both Nek5000 and PROTEUS. Some primary information on the configuration and build aspects for the SHARP toolkit, which includes capability to auto-download dependencies and configure/install with optimal flags in an architecture-aware fashion, is also covered by this report. A step-by-step instruction is provided to help users to create their cases. Details on these processes will be provided in the SHARP user manual that will accompany the first release.

Formation of binucleated myocardial cells in the neonatal rat. An index for growth hypertrophy

International Nuclear Information System (INIS)

Clubb, F.J. Jr.; Bishop, S.P.

1984-01-01

The purposes of this study were to characterize myocardial cell growth in neonatal rats and investigate the mechanism of binucleation in myocardial cells. To test the hypothesis that binucleated myocardial cells result from karyokinesis without cytokinesis, experiments were designed to measure the rate of DNA synthesis and the percentage of binucleated myocardial cells in neonatal rats during growth. Estimates of myocardial cell nuclear divisions were obtained from rats pulsed with tritiated thymidine at 17 days of gestation. Autoradiograms were prepared from isolated myocardial cells of rats killed at various ages postpartum, and the number of developed silver halide grains over myocardial cell nuclei was calculated. This estimated the mitotic activity of nuclei. To determine myocardial cell DNA synthesis postpartum, another set of rats were injected at various time periods with 4 hourly doses of tritiated thymidine, and hearts were fixed by perfusion 1 hour later. Labeling index of myocardial cells was calculated (labeled/total myocardial cells) from autoradiograms. Results indicated that the growth of myocardial cells in period can be divided into three phases: (a) a hyperplastic phase, (b) a transitional phase, and (c) a hypertrophic phase. Binucleation of myocardial cells was not due to fusion of mononucleated cells

Diagnostic value of amplitude-phase analysis in myocardial infarct. Comparison with thallium perfusion scintigraphy and contrast ventrilography

International Nuclear Information System (INIS)

Garcheva, M.; Trindev, P.; Shejretova, E.; Stoyanova, N.; Kaloyanova, P.; Khadzhikostova, Kh.

1990-01-01

The evaluation is based on the results of investigation of 34 patients who have had myocardial infarct without rhythm disturbances. Compared to contrast ventrilography, the amplitude-phase analysis (APA) of 'rest' radionuclide ventrilography show 80% sensitivity and 100% specificity, as well as high accuracy in determination of the type and localization of the kinetic disturbances. The comparison with the thallium perfusion scintigraphy demonstrates the possibility of APA to vizualize abnormal kinetic area of the myocardial wall and shows its independent significance in the cases of doubtful findings. APA is a powerful tool for unambigious differentiating of hypokinetic from akinetic and diskinetic areas. 1 tab., 1 fig., 4 refs

Absolute coronary blood flow measurement and microvascular resistance in ST-elevation myocardial infarction in the acute and subacute phase

Energy Technology Data Exchange (ETDEWEB)

Wijnbergen, Inge; Veer, Marcel van ' t [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands); Lammers, Jeroen; Ubachs, Joey [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Pijls, Nico H.J., E-mail: nico.pijls@cze.nl [Department of Cardiology, Catharina Hospital, Eindhoven (Netherlands); Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven (Netherlands)

2016-03-15

Background/Purpose: In a number of patients with acute myocardial infarction (AMI), myocardial hypoperfusion, known as the no-reflow phenomenon, persists after primary percutaneous intervention (PPCI). The aim of this study was to evaluate the feasibility and safety of a new quantitative method of measuring absolute blood flow and resistance within the perfusion bed of an infarct-related artery. Furthermore, we sought to study no-reflow by correlating these measurements to the index of microvascular resistance (IMR) and the area at risk (AR) as determined by cardiac magnetic resonance imaging (CMR). Methods: Measurements of absolute flow and myocardial resistance were performed in 20 patients with ST-segment elevation myocardial infarction (STEMI), first immediately following PPCI and then again after 3–5 days. These measurements used the technique of thermodilution during a continuous infusion of saline. Flow was expressed in ml/min per gram of tissue within the area at risk. Results: The average time needed for measurement of absolute flow, resistance and IMR was 20 min, and all measurements could be performed without complication. A higher flow supplying the AR correlated with a lower IMR in the acute phase. Absolute flow increased from 3.14 to 3.68 ml/min/g (p = 0.25) and absolute resistance decreased from 1317 to 1099 dyne.sec.cm-5/g (p = 0.40) between the first day and fifth day after STEMI. Conclusions: Measurement of absolute flow and microvascular resistance is safe and feasible in STEMI patients and may allow for a better understanding of microvascular (dys)function in the early phase of AMI. - Highlights: • We measured absolute coronary blood flow and microvascular resistance in STEMI patients in the acute phase and in the subacute phase, using the technique of thermodilution with low grade intracoronary continuous infusion of saline. • These measurements are safe and feasible during PPCI in STEMI patients. • In STEMI patients, absolute flow

[Myocardial imaging in acute myocardial infarction using beta-methyl-p-(123I)-iodophenylpentadecanoic acid: comparison with 201Tl imaging and wall motion].

Science.gov (United States)

Naruse, H; Itano, M; Kondo, T; Kogame, T; Yamamoto, J; Morita, M; Kawamoto, H; Fukutake, N; Ohyanagi, M; Iwasaki, T

1992-01-01

Myocardial imaging using beta-methyl-p-(123I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial imagings with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (TL) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than TL in the subacute phase, although the uptake of BMIPP correlated with that of TL (tau = 0.82, p less than 0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase (tau = 0.50, p less than 0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and TL alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of TL and WM.

Myocardial delayed-enhancement CT: initial experience in children and young adults

Energy Technology Data Exchange (ETDEWEB)

Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

2017-10-15

Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

Myocardial delayed-enhancement CT: initial experience in children and young adults

International Nuclear Information System (INIS)

Goo, Hyun Woo

2017-01-01

Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

The relationship between myocardial blood flow and myocardial viability after reperfusion. Myocardial viability assessed by [sup 15]O-water-PET

Energy Technology Data Exchange (ETDEWEB)

Tsukagoshi, Joichi (Gunma Univ., Maebashi (Japan). School of Medicine)

1994-09-01

The purpose of this study was to examine the relationship between myocardial blood flow and myocardial viability in the ischemic canine myocardium after reperfusion. Transient ischemia was induced by 60-, 90-, and 180-minute occlusion of the left anterior descending coronary artery. Myocardial blood flow (MBF) was measured in the areas in which regional contractility was severely impaired (ehocardiographically akinetic or dyskinetic) in the early reperfusion period by [sup 15]O-water positron emission tomography (PET) 12 hours and 4 weeks after reperfusion. An MBF ratio of ischemic to nonischemic regions 12 hours after reperfusion was inversely correlated with the amount of histologically determined tissue necrosis (r=-0.74). The regional contractility recovered 4 weeks later in the areas where an MBF ratio was 0.48 or greater, but did not recover in the areas with a lower MBF ratio. Thus, myocardial viability can be appropriately predicted in the early phase of myocardial perfusion by PET with [sup 15]O-water even in the absence of metabolic imaging. (author).

Profile of MIBI liquid phase radiopharmaceutical for myocardial imaging

International Nuclear Information System (INIS)

I Daruwati; ME Sriyani; NK Oekar; N Zainuddin; KA Hanafiah

2016-01-01

The 99m Tc-MIBI radiopharmaceutical has been used in nuclear medicine in Indonesia for myocardial imaging. BATAN researchers have mastered the technology to manufacture MIBI as a lyophilized kit. A reformulation of MIBI radiopharmaceutical has been conducted to improve the stability of the kit especially in the liquid-phase kit. Basically, radiopharmaceuticals in liquid form are not different from the dry kit. However in the manufacturing of liquid-phase kit, lyophilization process was not done. To improve the stability of liquid kit, a reformulation of the components was conducted by using two separate vials (Formulation 2) and the characteristics were compared with the one-vial formulation (Formulation 1). The MIBI Formulation 2 consists of two vials, vial A containing 0.06 mg of SnCl 2 2H 2 O and 2.6 mg Sodium Citrate 2H 2 O and vial B containing 0.5 mg of [Cu(MIBI) 4 ]BF 4 , 1 mg of cysteine hydrochloride, and 20 mg of mannitol. The purposes of this study were to determine the stability of two different formulations of MIBI as a liquid-phase kit, to compare their stability in different storage condition such as in refrigerator and freezer, and to compare the ratio of activities attained between target and nontarget organs after injection to animal model. As a diagnostic agent, MIBI was reconstituted with Technetium-99m as radionuclide tracer to 99m Tc-MIBI labeled compound. The radiochemical purity of 99m Tc-MIBI was determined by chromatography method using alumina thin-layer chromatography paper as the stationary phase and ethanol 95% as the mobile phase. The results showed MIBI Formulation 2 has a higher stability than Formulation 1. Formulation 2 also maintained a 96.68% radiochemical purity under 52-day storage and attained a target-to-nontarget activity ratio of 8.22. (author)

Evaluation of the prevalence of stress and its phases in acute myocardial infarction in patients active in the labor market

Directory of Open Access Journals (Sweden)

Luciane Boreki Lucinda

2015-02-01

Full Text Available Introduction: Acute myocardial infarction is a social health problem of epidemiological relevance, with high levels of morbidity and mortality. Stress is one of the modifiable risk factors that triggers acute myocardial infarction. Stress is a result of a set of physiological reactions, which when exaggerated in intensity or duration can lead to imbalances in one's organism, resulting in vulnerability to diseases. Objective: To identify the presence of stress and its phases in hospitalized and active labor market patients with unstable myocardial infarction and observe its correlation with the life of this population with stress. Methods: The methodology used was a quantitative, descriptive and transversal research approach conducted with a total of 43 patients, who were still active in the labor market, presenting or not morbidities. Data collection occurred on the fourth day of their hospitalization and patients responded to Lipp's Stress Symptom Inventory for adults. Results: Thirty-one patients (72.1% presented stress and twelve (27.8% did not. In patients with stress, the identified phases were: alert - one patient (3.2%; resistance -twenty-two patients (71.0%; quasi-exhaustion - six patients (19.4% and exhaustion - two patients (6.5%. All women researched presented stress. Conclusion: The results suggest a high level of stress, especially in the resistance phase, in the male infarcted population, hospitalized and active in the labor market.

The diagnostic value of Tc-99m PYP, Tl-201 dual isotope SPECT to predict the viability of damaged myocardium in the acute phase of myocardial infarction

International Nuclear Information System (INIS)

Matsuo, Hitoshi; Watanabe, Sachiro; Arai, Masazumi

1991-01-01

To assess the diagnostic value of Tc-99m pyrophosphate (PYP), Tl-201 dual isotope SPECT for the evaluation of myocardial viability, segmental comparison between dual isotope SPECT and exercise, delayed, and reinjected Tl study were performed with 18 acute myocardial infarction (AMI) patients. Among 72 damaged myocardial segments, 48 segments (67%) were judged as viable by chronic phase Tl studies. The segments with severely reduced Tl uptake by dual SPECT showed significantly lower prevalence of viable myocardium than the segments with reduced and normal Tl uptake (p<0.001). The segments with PYP accumulation localized to the subendocardium represented the favorable outcome compared with the transmural accumulation (p<0.001). And overlap segments show better prognosis than the segments without overlap (p<0.05). Most importantly, we can get better predictive accuracy of myocardial scar by dual isotope SPECT than the judgement by Tl or PYP SPECT alone (83.3% vs 77.8%, 68.1%). Thus, we conclude that Tc-99m PYP, Tl-201 dual isotope SPECT is useful to assess the severity of myocardial damage in the acute phase of myocardial infarction. (author)

Myocardial imaging in acute myocardial infarction using. beta. -methyl-p-( sup 123 I)-iodophenylpentadecanoic acid; Comparison with sup 201 Tl imaging and wall motion

Energy Technology Data Exchange (ETDEWEB)

Naruse, Hitoshi; Itano, Midoriko; Kondo, Tomohiro (Hyogo College of Medicine, Nishinomiya (Japan)) (and others)

1992-01-01

Myocardial imaging using {beta}-methyl-p-({sup 123}I)-iodophenylpentadecanoic acid (BMIPP) was performed in 11 patients with acute myocardial infarction. The left ventricular images were divided into 12 segments, and myocardial images with BMIPP were compared with coronary angiography (CAG), thallium-201 myocardial scintigraphy (Tl) and wall motion obtained by two-dimensional echocardiography (WM). When the culprit lesion was at the proximal point of the left anterior descending artery (LAD), all segments showed depressed uptake. In 3 cases with single vessel disease of the LAD, inferior wall of the basis showed reduced uptake of BMIPP despite the location of the culprit lesion. In cases with discordant uptake between the two tracers, BMIPP frequently showed more severely depressed uptake than Tl in the subacute phase, although the uptake of BMIPP correlated with that of Tl ({tau}=0.82, p<0.001). In such cases, the discordance was related to the improvement in WM from the acute phase to the convalescent phase. BMIPP uptake correlated with WM in the subacute phase ({tau}=0.50, p<0.001). BMIPP showed more severely depressed uptake while WM showed mild asynergy in most cases in which discordance was found between the BMIPP and WM findings. However, there was no correlation between the change in WM from the acute to subacute phases, or the uptakes of BMIPP and Tl alone. We concluded that the myocardial condition can be evaluated in detail in acute myocardial infarction by comparing the findings of BMIPP with those of Tl and WM. (author).

Increased platelet aggregation and turnover in the acute phase of ST-elevation myocardial infarction

DEFF Research Database (Denmark)

Jensen, Kristian Løkke Funck; Dalsgaard, Jens; Grove, Erik Lerkevang

2013-01-01

Newly produced platelets are present in the acute phase of ST-elevation myocardial infarction (STEMI). This may influence the antiplatelet effect of aspirin and clopidogrel administered prior to primary percutaneous coronary intervention (PPCI). The aims of this study were to investigate the anti...... turnover may partly explain the reduced efficacy of antiplatelet drugs in the acute phase of STEMI....... the antiplatelet effect of aspirin and clopidogrel and evaluate platelet turnover in the acute phase of STEMI compared to a stable phase 3 months later. In this observational follow-up study on 48 STEMI patients transferred for PPCI, loading doses of aspirin (300 mg) and clopidogrel (600 mg) were given orally...... in the ambulance. Blood samples were obtained immediately prior to PPCI, at 4 and 12 hours after administration of bolus doses and at follow-up after 3 months. Residual platelet aggregation was evaluated by Multiplate® and VerifyNow® aggregometry. Platelet turnover was evaluated by automated flow cytometry...

Role of myocardial perfusion imaging in evaluating thrombolytic therapy for acute myocardial infarction

International Nuclear Information System (INIS)

Beller, G.A.

1987-01-01

Myocardial thallium-201 scintigraphy is being increasingly employed as a method for assessing the efficacy of coronary reperfusion in acute myocardial infarction. New thallium uptake after intracoronary tracer administration after successful recanalization indicates that nutrient blood flow has been successfully restored. One may also presume that some myocardial salvage occurred if thallium administered in this manner is transported intracellularly by myocytes with intact sarcolemmal membranes. However, if one injects thallium by way of the intracoronary route immediately after reperfusion, the initial uptake of thallium in reperfused myocardium may predominantly represent hyperemic flow and regional thallium counts measured may not be proportional to the mass of viable myocytes. When thallium is injected intravenously during the occlusion phase the degree of redistribution after thrombolysis is proportional to the degree of flow restoration and myocardial viability. When thallium is injected for the first time intravenously immediately after reperfusion, an overestimation of myocardial salvage may occur because of excess thallium uptake in the infarct zone consequent to significant hyperemia. Another approach to myocardial thallium scintigraphy in patients undergoing thrombolytic therapy is to administer two separate intravenous injections before and 24 hours or later after treatment. Finally, patients with acute myocardial infarction who receive intravenous thrombolytic therapy are candidates for predischarge exercise thallium-201 scintigraphy for risk stratification and detection of residual ischemia

Myocardial scintigraphy with thallium-201

International Nuclear Information System (INIS)

Schwaiger, M.; Silber, S.; Klein, U.; Rudolph, W.

1980-01-01

Thallium-201 myocardial scintigraphy is an important non-invasive method for assessment of coronary artery disease. Other applications of the method such as delineation of the right ventricular free wall in right ventricular overload, or the detection of hypertrophic cardiomyopathies or myocardial infiltrations are of subordinate importance. In heart disease such as congestive cardiomyopathy and mitral valve prolapse thallium-201 uptake defects have been described, the clinical implications of these findings, however, cannot be adequately interpreted at this time. Myocardial uptake of thallium-201 is an active process, dependent on and proportional to perfusion. Differentiation between myocardial ischemia and myocardial scar is based on the presence or absence of thallium-201 'redistribution'. That is, in the presence of acute reversible ischemia there is increased thallium-201 uptake in the post-ischemic phase in previously hypoperfused myocardium and, subsequently, equilibrium of the initially registered activity differences. 'Redistribution' has also been described in the resting scintigram of patients with severe coronary artery disease and chronic hypoperfusion. (orig.) [de

The association between reconstructed phase space and Artificial Neural Networks for vectorcardiographic recognition of myocardial infarction.

Science.gov (United States)

Costa, Cecília M; Silva, Ittalo S; de Sousa, Rafael D; Hortegal, Renato A; Regis, Carlos Danilo M

Myocardial infarction is one of the leading causes of death worldwide. As it is life threatening, it requires an immediate and precise treatment. Due to this, a growing number of research and innovations in the field of biomedical signal processing is in high demand. This paper proposes the association of Reconstructed Phase Space and Artificial Neural Networks for Vectorcardiography Myocardial Infarction Recognition. The algorithm promotes better results for the box size 10 × 10 and the combination of four parameters: box counting (Vx), box counting (Vz), self-similarity method (Vx) and self-similarity method (Vy) with sensitivity = 92%, specificity = 96% and accuracy = 94%. The topographic diagnosis presented different performances for different types of infarctions with better results for anterior wall infarctions and less accurate results for inferior infarctions. Copyright © 2018 Elsevier Inc. All rights reserved.

Cardiac functional mapping for thallium-201 myocardial perfusion, washout, wall motion and phase using single-photon emission computed tomography (SPECT)

International Nuclear Information System (INIS)

Nakajima, Kenichi; Bunko, Hisashi; Taniguchi, Mitsuru; Taki, Junichi; Tonami, Norihisa; Hisada, Kinichi; Hirano, Takako; Wani, Hidenobu.

1986-01-01

A method for three-dimensional functional mapping of Tl-201 myocardial uptake, washout, wall motion and phase was developed using SPECT. Each parameter was mapped using polar display in the same format. Normal values were determined in Tl-201 exercise study in 16 patients. Myocardial counts were lower in the septum and inferior wall and the difference of counts between anterior and inferior walls were greater in man compared with the perfusion pattern in woman. Washout was slower at septum and inferior wall in man, and slightly slower at inferior wall in woman. In gated blood-pool tomography, length-based and count-based Fourier analyses were applied to calculate the parameters of contraction and phase. The results of both Fourier analyses generally agreed; however, the area of abnormality was slightly different. Phase maps were useful for the assessment of asynergy as well as in patients with conduction disorders. These cardiac functional maps using SPECT were considered to be effective for the understanding of three-dimensional informations of cardiac function. (author)

Sharps container

Science.gov (United States)

Lee, Angelene M. (Inventor)

1992-01-01

This invention relates to a system for use in disposing of potentially hazardous items and more particularly a Sharps receptacle for used hypodermic needles and the like. A Sharps container is constructed from lightweight alodined nonmagnetic metal material with a cup member having an elongated tapered shape and length greater than its transverse dimensions. A magnet in the cup member provides for metal retention in the container. A nonmagnetic lid member has an opening and spring biased closure flap member. The flap member is constructed from stainless steel. A Velcro patch on the container permits selective attachment at desired locations.

Almost sharp quantum effects

International Nuclear Information System (INIS)

Arias, Alvaro; Gudder, Stan

2004-01-01

Quantum effects are represented by operators on a Hilbert space satisfying 0≤A≤I, and sharp quantum effects are represented by projection operators. We say that an effect A is almost sharp if A=PQP for projections P and Q. We give simple characterizations of almost sharp effects. We also characterize effects that can be written as longer products of projections. For generality we first work in the formalism of von Neumann algebras. We then specialize to the full operator algebra B(H) and to finite dimensional Hilbert spaces

Sharp superconductor-insulator transition in short wires

International Nuclear Information System (INIS)

Meidan, Dganit; Oreg, Yuval; Refael, Gil; Smith, Robert A.

2008-01-01

Recent experiments on short MoGe nanowires show a sharp superconductor-insulator transition tuned by the normal state resistance of the wire, with a critical resistance of R c ∼ R Q = h/(4e 2 ). These results are at odds with a broad range of theoretical work on Josephson-like systems that predicts a smooth transition, tuned by the value of the resistance that shunts the junction. We develop a self-consistent renormalization group treatment of interacting phase-slips and their dual counterparts, correlated cooper pair tunneling, beyond the dilute approximation. This analysis leads to a very sharp transition with a critical resistance of R Q . The addition of the quasi-particles' resistance at finite temperature leads to a quantitative agreement with the experimental results. This self-consistent renormalization group method should also be applicable to other physical systems that can be mapped onto similar sine-Gordon models, in the previously inaccessible intermediate-coupling regime

Selective coronarography and ventriculography with Iopamidol in the acute phase of myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Ricci Maccarini, P; Benenati, P M; Bellanti, G; Piscitelli, G

1988-01-01

The new techniques for an early treatement of acute myocardial infarction (AMI), such as thrombolysis and percutaneous transluminal angioplasty, often necessitate rapid and accurate radiological evaluation of coronaric lesions and left ventricular function. The aim of the present study was to evaluate both safety and tolerability of selective coronarography (SC) and left ventriculography (LVG), with iopamidol 370 mg I/ml as a contrast medium, in the acute phase of AMI. Thirty-nine patients aged 26-29 years, were examined: 18 group A, within 4 days (mean 2.6+-0.8 SD) and 21, group B, within 5-15 days after AMI (mean 8.8+-3 SD). Contrast media (cm) dosage varied from 150 to 300 ml (2.43-5.5 ml/bw). During the procedure, ECG was continuosly recorded; left ventricular pressure was registered immediately and 30 minutes after cm administration. During the following 9 days ECG tracings and plasmatic cytolysisenzymes were monitored. During the examination no patient complained of any symptoms. After LVG slight elevations in end diastolic pressure were detected in all patients (mean increase 4.7 mmHg), which were not relevant from a clinical point of view. In 11/39 cases ventricular tachycardia was observed, which spontaneously ceased. During SC no change in ECG tracings was registered except in one patient, group A, in whom complete transitory heart block was detected. After SC no alteration in instrumental and biochemical parameters was registered except in one patient, group B, in whom a reinfarction due to right coronaric artery occlusion was observed. In conclusion, these results suggest that both SC and LVG with iopamidol are safe techniques also in the early phase of myocardial infarction. 24 refs.

Myocardial protection in heart surgery.

Science.gov (United States)

Mentzer, Robert M

2011-01-01

One of the unmet clinical needs in heart surgery is the prevention of myocardial stunning and necrosis that occurs as a result of ischemia-reperfusion. Myocardial stunning, a frequent consequence after heart surgery, is characterized by a requirement for postoperative inotropic support despite a technically satisfactory heart operation. In high-risk patients with marginal cardiac reserve, stunning is a major cause of prolonged critical care and may be associated with as much as a 5-fold increase in mortality. In contrast, the frequency of myocardial necrosis (myocardial infarction [MI]) after cardiac surgery is less appreciated and its consequences are much more subtle. The consequences may not be apparent for months to years. While we now have a much better understanding of the molecular mechanisms underlying myocardial stunning and MI, we still have no effective way to prevent these complications, nor a consistently effective means to engage the well-studied endogenous mechanisms of cardioprotection. The failure to develop clinically effective interventions is multifactorial and can be attributed to reliance on findings obtained from subcellular and cellular studies, to drawing conclusions from preclinical large animal studies that have been conducted in a disease-free state, and to accepting less than robust surrogate markers of injury in phase II clinical trials. These factors also explain the disappointing failure to identify effective adjuvant therapy in the setting of percutaneous coronary revascularization for acute MI (AMI) and reperfusion injury. These issues have contributed to the disappointing outcomes of large and costly phase III trials, resulting in a lack of enthusiasm on the part of the pharmaceutical industry to engage in further drug development for this indication. The purpose of this review is to (1) define the scope of the clinical problem; (2) summarize the outcomes of selected phases II and III clinical trials; and (3) identify the gap that

Analysis of sharpness increase by image noise

Science.gov (United States)

Kurihara, Takehito; Aoki, Naokazu; Kobayashi, Hiroyuki

2009-02-01

Motivated by the reported increase in sharpness by image noise, we investigated how noise affects sharpness perception. We first used natural images of tree bark with different amounts of noise to see whether noise enhances sharpness. Although the result showed sharpness decreased as noise amount increased, some observers seemed to perceive more sharpness with increasing noise, while the others did not. We next used 1D and 2D uni-frequency patterns as stimuli in an attempt to reduce such variability in the judgment. The result showed, for higher frequency stimuli, sharpness decreased as the noise amount increased, while sharpness of the lower frequency stimuli increased at a certain noise level. From this result, we thought image noise might reduce sharpness at edges, but be able to improve sharpness of lower frequency component or texture in image. To prove this prediction, we experimented again with the natural image used in the first experiment. Stimuli were made by applying noise separately to edge or to texture part of the image. The result showed noise, when added to edge region, only decreased sharpness, whereas when added to texture, could improve sharpness. We think it is the interaction between noise and texture that sharpens image.

Clinical usefulness of technetium-99m pyrophosphate and Tl-201 myocardial imaging for the estimation of myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Suzuki, Akio; Sato, Akihiko; Miyakoda, Hiroyuki; Watanabe, Toshiya; Itatsu, Hidetaka; Ueda, Osamu; Sakurai, Kuniteru; Kawai, Naoki; Sotobata, Iwao

1985-04-01

A correlative study was performed between the infarct size estimated by either technetium-99 pyrophosphate (Tc-PYP) or Tl-201 myocardial imaging, and the cumulative total creatinine phosphokinase activity (..sigma..CPK) or left ventricular ejection fraction (LVEF) in 40 patients with acute myocardial infarction. Tc-PYP infarct area (TcIA) and mean Tl-201 uptake ratio (MUR) were calculated as indices of myocardial infarct size. LVEF was evaluated by first pass method using Tc-PYP in the acute phase of myocardial infraction. In 23 patients with anterior myocardial infarction, a significant correlation was shown between either TcIA or anterior-wall MUR and ..sigma..CPK (r=0.81 and r=-0.69, respectively) and also between either TcIA or anterior-wall MUR and LVEF (r=-0.84 and r=0.80, respectively). In 17 patients with inferior myocardial infarction without additional involvement of right ventricular wall, inferior-wall MUR correlated with ..sigma..CPK (r=-0.74). No statically significant correlation was shown between TcIA and ..sigma..CPK, and also between either TcIA or inferior-wall MUR and LVEF. In conclusion, the infarct size estimated with Tc-PYP or Tl-201 myocardial imaging could be a useful clinical indicator of the severity of acute myocardial infarction especially in anterior wall. (author).

The stratigraphy and evolution of lower Mount Sharp from spectral, morphological, and thermophysical orbital data sets.

Science.gov (United States)

Fraeman, A A; Ehlmann, B L; Arvidson, R E; Edwards, C S; Grotzinger, J P; Milliken, R E; Quinn, D P; Rice, M S

2016-09-01

We have developed a refined geologic map and stratigraphy for lower Mount Sharp using coordinated analyses of new spectral, thermophysical, and morphologic orbital data products. The Mount Sharp group consists of seven relatively planar units delineated by differences in texture, mineralogy, and thermophysical properties. These units are (1-3) three spatially adjacent units in the Murray formation which contain a variety of secondary phases and are distinguishable by thermal inertia and albedo differences, (4) a phyllosilicate-bearing unit, (5) a hematite-capped ridge unit, (6) a unit associated with material having a strongly sloped spectral signature at visible near-infrared wavelengths, and (7) a layered sulfate unit. The Siccar Point group consists of the Stimson formation and two additional units that unconformably overlie the Mount Sharp group. All Siccar Point group units are distinguished by higher thermal inertia values and record a period of substantial deposition and exhumation that followed the deposition and exhumation of the Mount Sharp group. Several spatially extensive silica deposits associated with veins and fractures show that late-stage silica enrichment within lower Mount Sharp was pervasive. At least two laterally extensive hematitic deposits are present at different stratigraphic intervals, and both are geometrically conformable with lower Mount Sharp strata. The occurrence of hematite at multiple stratigraphic horizons suggests redox interfaces were widespread in space and/or in time, and future measurements by the Mars Science Laboratory Curiosity rover will provide further insights into the depositional settings of these and other mineral phases.

Focusing optical waves with a rotationally symmetric sharp-edge aperture

Science.gov (United States)

Hu, Yanwen; Fu, Shenhe; Li, Zhen; Yin, Hao; Zhou, Jianying; Chen, Zhenqiang

2018-04-01

While there has been various kinds of patterned structures proposed for wave focusing, these patterned structures usually involve complicated lithographic techniques since the element size of the patterned structures should be precisely controlled in microscale or even nanoscale. Here we propose a new and straightforward method for focusing an optical plane wave in free space with a rotationally symmetric sharp-edge aperture. The focusing phenomenon of wave is realized by superposition of a portion of the higher-order symmetric plane waves generated from the sharp edges of the apertures, in contrast to previously focusing techniques which usually depend on a curved phase. We demonstrate both experimentally and theoretically the focusing effect with a series of apertures having different rotational symmetry, and find that the intensity of the hotspots could be controlled by the symmetric strength of the sharp-edge apertures. The presented results would advance the conventional wisdom that light would diffract in all directions and become expanding when it propagates through an aperture. The proposed method is easy to be processed, and might open potential applications in interferometry, image, and superresolution.

The SHARP scramjet launcher

Energy Technology Data Exchange (ETDEWEB)

Cartland, H.; Fiske, P.; Greenwood, R.; Hargiss, D.; Heston, P.; Hinsey, N.; Hunter, J.; Massey, W.

1995-01-10

The worlds largest light gas gun at SHARP (Super High Altitude Research Project) is completed and in the past year has launched 9 scramjets. Typical masses and velocities are 5.9 kg at 2.8 km/sec.and 4.4 kg at 3.1 km/sec. In so doing SHARP launched the first fully functioning, hydrogen burning scramjet at mach 8. The SHARP launcher is unique in having a 4 inch diameter and 155 foot-long barrel. This enables lower acceleration launches than any other system. In addition the facility can deliver high energy projectiles to targets in the open air without having to contain the impact fragments. This allows one to track lethality test debris for several thousand feet.

Equilibrium radionuclide ventriculography in male patients after transmural myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Nestaval, A; Stanek, V; Malek, I; Kidery, J; Runczik, I [Institut pro Klinickou a Experimentalni Medicinu, Prague (Czechoslovakia); Cernoch, V; Oppelt, A [Institut pro Dalsi Vzdelavani Lekaru a Farmaceutu, Prague (Czechoslovakia)

1982-12-17

The ejection fraction of the left ventricle was measured using the method of equilibrium radionuclide ventriculography in 10 healthy males and 57 males after the first transmural myocardial infarction. The examination was effected 4 to 7 months after the event and the sample is representative for males after myocardial infarction who are younger than 65 years and show no signs of heart insufficiency by the time of examination. The resting value of the ejection fraction was 63+-5% in healthy males, 54+-7% in patients with uncomplicated myocardial infarction and 37+-8% in patients with clinical manifestations of heart insufficiency in acute phase. The differences between the groups are statistically significant. In patients with anteroseptal localization of myocardial infarction there was a negative correlation between the ejection fraction on the one hand and the sum of the voltages of Q waves in precordial ECG map and the maximum value of serum creatine kinase in acute phase on the other. The ejection fraction was in correlation to the degree of pulmonary hypertension measured in equal phase during exercise. The ejection fraction was measured in 31 patients under the working load of 50 W; significant changes were not found in healthy males or in patients after myocardial infarction. No changes were found when the state just before discharge from the hospital was compared with his state 6 months after myocardial infarction. The results obtained in compensated patients showed a relative stability of the value of the ejection fraction both during the first 6 months after discharge and under a mild working load. A comparison between the indicators in acute phase and hemodynamic examination after 6 months shows that the value of the ejection fraction is a sensitive indicator of the extent of necrosis and functional lesion of the left ventricle.

Myocardial perfusion in silent myocardial ischemia

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

1989-01-01

To investigate myocardial perfusion in silent myocardial ischemia, we performed exercise stress myocardial tomography with thallium-201 (Tl) in 85 patients with coronary artery disease (CAD). Exercise stress myocardial tomography was obtained both immediately after exercise and three hours later. Patients were classified into two groups according to the presence (Symptomatic Group, n=36) or absence (Silent Group, n=49) of chest pain during exercise stress. Clinical features (age, gender and history of myocardial infarction) and arteriographically determined severity of CAD were the same in both groups. The extent of myocardial ischemia (% Ischemia) estimated by exercise stress myocardial tomography was the same in each group (30±10 % in Silent Group, 28±12 % in Symptomatic Group, NS). The severity of exercise-induced myocardial ischemia was expressed as a minimal value of myocardial Tl washout rate (minimal WOR) of each patient. Although exercise heart rate was identical in both groups, minimal WOR in Silent Group was significantly higher than that of Symptomatic Group (4±10% vs -16±14%, p<0.001). The study in patients who exhibited both silent and symptomatic ischemia showed the same results. These findings suggest that the severity of ischemia is a fundamental factor in determining the presence or absence of pain during exercise induced ischemia. (author)

Dose-dependent effects of atorvastatin on myocardial infarction

Directory of Open Access Journals (Sweden)

Barbarash O

2015-06-01

Full Text Available Olga Barbarash, Olga Gruzdeva, Evgenya Uchasova, Ekaterina Belik, Yulia Dyleva, Victoria KaretnikovaFederal State Budgetary Institution, Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo, the Russian Federation Background: Dyslipidemia is a key factor determining the development of both myocardial infarction (MI and its subsequent complications. Dyslipidemia is associated with endothelial dysfunction, activation of inflammation, thrombogenesis, and formation of insulin resistance. Statin therapy is thought to be effective for primary and secondary prevention of complications associated with atherosclerosis.Methods: This study examined 210 patients with Segment elevated MI (ST elevated MI who were treated with atorvastatin from the first 24 hours after MI. Group 1 (n=110 were given atorvastatin 20 mg/day. Group 2 (n=100 were given atorvastatin 40 mg/day. At days 1 and 12 after MI onset, insulin resistance levels determined by the homeostasis model assessment of insulin resistance index, lipid profiles, and serum glucose, insulin, adipokine, and ghrelin levels were measured.Results: Free fatty acid levels showed a sharp increase during the acute phase of MI. Treatment with atorvastatin 20 mg/day, and especially with 40 mg/day, resulted in a decrease in free fatty acid levels. The positive effect of low-dose atorvastatin (20 mg/day is normalization of the adipokine status. Administration of atorvastatin 20 mg/day was accompanied with a statistically significant reduction in glucose levels (by 14% and C-peptide levels (by 38%, and a decrease in the homeostasis model assessment of insulin resistance index on day 12.Conclusion: Determination of atorvastatin dose and its use during the in-hospital period and subsequent periods should take into account changes in biochemical markers of insulin resistance and adipokine status in patients with MI.Keywords: myocardial infarction, statin, insulin resistance, adipokines

SHARP's systems engineering challenge: rectifying integrated product team requirements with performance issues in an evolutionary spiral development acquisition

Science.gov (United States)

Kuehl, C. Stephen

2003-08-01

Completing its final development and early deployment on the Navy's multi-role aircraft, the F/A-18 E/F Super Hornet, the SHAred Reconnaissance Pod (SHARP) provides the war fighter with the latest digital tactical reconnaissance (TAC Recce) Electro-Optical/Infrared (EO/IR) sensor system. The SHARP program is an evolutionary acquisition that used a spiral development process across a prototype development phase tightly coupled into overlapping Engineering and Manufacturing Development (EMD) and Low Rate Initial Production (LRIP) phases. Under a tight budget environment with a highly compressed schedule, SHARP challenged traditional acquisition strategies and systems engineering (SE) processes. Adopting tailored state-of-the-art systems engineering process models allowd the SHARP program to overcome the technical knowledge transition challenges imposed by a compressed program schedule. The program's original goal was the deployment of digital TAC Recce mission capabilities to the fleet customer by summer of 2003. Hardware and software integration technical challenges resulted from requirements definition and analysis activities performed across a government-industry led Integrated Product Team (IPT) involving Navy engineering and test sites, Boeing, and RTSC-EPS (with its subcontracted hardware and government furnished equipment vendors). Requirements development from a bottoms-up approach was adopted using an electronic requirements capture environment to clarify and establish the SHARP EMD product baseline specifications as relevant technical data became available. Applying Earned-Value Management (EVM) against an Integrated Master Schedule (IMS) resulted in efficiently managing SE task assignments and product deliveries in a dynamically evolving customer requirements environment. Application of Six Sigma improvement methodologies resulted in the uncovering of root causes of errors in wiring interconnectivity drawings, pod manufacturing processes, and avionics

Evaluation of 99mTc-nitroimidazole in animal of myocardial necrosis

International Nuclear Information System (INIS)

Shimpi, H.H.; Mahapatra, S.; Noronha, O.P.D.

1998-01-01

Full text: Extensive studies carried out using 99m Tc-nitroimidazole (BMS 181321) suggested that it is a useful agent to investigate the status of hypoxia in solid tumors and ischemic myocardium. In vitro studies also showed that 99m Tc nitroimidazole is preferentially trapped in and retained by hypoxic, but viable cardiac muscle. We have evaluated the compound in an animal (rat) model of myocardial necrosis. 99m Tc-nitromidazole was labelled with 99m Tc by using cyclan and Sn-glucaric acid. The radiochemical purity was >95%. It was found to be very stable. Experimental (rat) animal of myocardial necrosis or ischemic necrosis was obtained by injecting iso proternol HCl subcutaneously (S.C.) at a dose of 5.25 mg/kg body weight. After 48 h, gross and microscopic necrotic changes were seen in the heart which closely resembled the myocardial infarct of necrotic lesion akin to ischemic necrosis of the myocardium. Animal biodistribution study demonstrated that 99m Tc nitroimidazole cleared very fast from the blood stream of both normal system. Significantly higher uptake was seen in heart of experimental animals compared to normal animals at 60 min. The ratios of heart to blood, liver and kidneys in both normal and experimental animals showed significantly higher ratios in experimental animals. The heart to blood ratio of experimental animal remained same up to 60 min. compared to a sharp decline with time in normal animals. The above results show that 99m Tc-nitroimidazole could be used for detection of myocardial necrosis or myocardial infarct in clinical conditions

Sharp at any Age: Moho boundary thickness estimates along a trans-sect through 2 Ga of tectonic history.

Science.gov (United States)

Servali, A.; Levin, V. L.; VanTongeren, J. A.

2015-12-01

In this study we evaluate crustal thickness and Moho sharpness beneath seismic stations in three different tectonic units of the North American continent: the Archean Superior Province, the Proterozoic Grenville Province, and the Paleozoic Appalachian Orogen. Our analysis involves two steps. First, for each site, we produce P-to-S receiver functions (RFs) organized by backazimuth and epicentral distance, and use them to identify the phase most likely representing a conversion from the Moho. Second, we construct averaged RFs for groups of telesismic events located in a similar geographic region, which we employ to examine shapes of Moho P-to-S converted phases in time series with maximum frequencies increasing from 0.25Hz to 2-3 Hz. At some sites we observe a progressive narrowing of a simple Moho converted phase with an increase in frequency, typical of a vertically instantaneous boundary, while at others the converted phase becomes progressively more complex, typical of a diffuse Moho. Thus, we adopt this difference in converted wave shape dependence on increasing frequency as a measure of Moho thickness. Our estimates of Moho thickness range from less than 300 m to over 2 km, with some locations showing evidence for multiple converting boundaries in the 35-50 km depth range. In this study we define "sharp" Moho at those sites where its vertical thickness is less than 1 km. Our results show that sharp Moho is universal in the Archean terranes regardless of surface lithology, likely due to higher Moho temperatures facilitating wide-spread delamination of dense lower crustal rocks. While a sharp Moho is not unique to the Superior Province, all Grenville and Appalachians sites where we find sharp Moho are in regions of granitic plutonism, suggesting a possible general association with reworking and density sorting of the crustal material (e.g. volcanic arc).

Nuclear medicine methods in the field of studying the mechanisms of delayed phase of myocardial preconditioning

International Nuclear Information System (INIS)

Wang Shuxia

2001-01-01

Ischemic preconditioning is the intrinsic and most potently myocardial protection. Its mechanism is the foundation of rational therapeutic application. Nowadays there are some theories about delayed phase of preconditioning such as nitric oxide hypothesis, free radical mechanisms, protective protein synthesis and opening of ATP-sensitive potassium channels. By incorporation 3 H-leucine, using liquid scintillation counter, the authors know there was protective protein synthesis during preconditioning. SPECT could study the characteristics of preconditioned myocardium in vivo, and PET might further show the metabolism, energy consumption and its relationship to myocardium dysfunction

Summer High School Apprenticeship Research Program (SHARP)

Science.gov (United States)

1997-01-01

The summer of 1997 will not only be noted by NASA for the mission to Mars by the Pathfinder but also for the 179 brilliant apprentices that participated in the SHARP Program. Apprentice participation increased 17% over last year's total of 153 participants. As indicated by the End-of-the-Program Evaluations, 96% of the programs' participants rated the summer experience from very good to excellent. The SHARP Management Team began the year by meeting in Cocoa Beach, Florida for the annual SHARP Planning Conference. Participants strengthened their Education Division Computer Aided Tracking System (EDCATS) skills, toured the world-renowned Kennedy Space Center, and took a journey into space during the Alien Encounter Exercise. The participants returned to their Centers with the same goals and objectives in mind. The 1997 SHARP Program goals were: (1) Utilize NASA's mission, unique facilities and specialized workforce to provide exposure, education, and enrichment experiences to expand participants' career horizons and inspire excellence in formal education and lifelong learning. (2) Develop and implement innovative education reform initiatives which support NASA's Education Strategic Plan and national education goals. (3) Utilize established statistical indicators to measure the effectiveness of SHARP's program goals. (4) Explore new recruiting methods which target the student population for which SHARP was specifically designed. (5) Increase the number of participants in the program. All of the SHARP Coordinators reported that the goals and objectives for the overall program as well as their individual program goals were achieved. Some of the goals and objectives for the Centers were: (1) To increase the students' awareness of science, mathematics, engineering, and computer technology; (2) To provide students with the opportunity to broaden their career objectives; and (3) To expose students to a variety of enrichment activities. Most of the Center goals and

The Spectral Sharpness Angle of Gamma-ray Bursts

Directory of Open Access Journals (Sweden)

Hendrik J. van Eerten

2016-06-01

Full Text Available We extend the results of Yu et al. (2015b of the novel sharpness angle measurement to a large number of spectra obtained from the Fermi gamma-ray burst monitor. The sharpness angle is compared to the values obtained from various representative emission models: blackbody, single-electron synchrotron, synchrotron emission from a Maxwellian or power-law electron distribution. It is found that more than 91% of the high temporally and spectrally resolved spectra are inconsistent with any kind of optically thin synchrotron emission model alone. It is also found that the limiting case, a single temperature Maxwellian synchrotron function, can only contribute up to 58+23 -18% of the peak flux. These results show that even the sharpest but non-realistic case, the single-electron synchrotron function, cannot explain a large fraction of the observed spectra. Since any combination of physically possible synchrotron spectra added together will always further broaden the spectrum, emission mechanisms other than optically thin synchrotron radiation are likely required in a full explanation of the spectral peaks or breaks of the GRB prompt emission phase.

The values of myocardial tomography imaging and gated cardiac blood pool imaging in detecting left ventricular aneurysm

International Nuclear Information System (INIS)

Zhu Mei; Pan Zhongyun; Li Jinhui

1992-01-01

The sensitivity and specificity of myocardial tomography imaging and gated cardiac blood-pool imaging in detecting LVA were studied in 36 normal subjects and 68 patients with myocardial infarction. The sensitivities of exercise and rest myocardial imaging in detecting LVA were 85% and 77.3% respectively. The specificity of both is 95.5%. The sensitivity of cinema display, phase analysis and left ventricular phase shift in evaluating LVA were 86.7%, 86.7%, 100% respectively. Their specificity were all 100%. It is concluded that blood pool imaging is of choice for the diagnosis of LVA, and that myocardial imaging could also demonstrate LVA during diagnosing myocardial infarction

Spouses' conceptions of the pre-hospital phase when their partners suffered an acute myocardial infarction--a qualitative analysis.

Science.gov (United States)

Johansson, Ingela; Swahn, Eva; Strömberg, Anna

2008-09-01

Delay from onset of acute myocardial infarction symptoms to the delivery of medical care is a major determinant of prognosis. Although studies have explored patient reasons for delay, there are only limited data concerning experiences of the spouse. Was to describe spouses' conceptions of the pre-hospital phase when their partners suffered an acute myocardial infarction. A phenomenographic approach was applied. Fifteen spouses were interviewed rational, and consulting others. The category respecting independence contained: accepting the need for control, marital roles and experiences, restraining emotions, and seeking agreement. Our findings suggest that spouses have a strong influence on the course of events. When accepting the partner's need for control through following earlier marital roles and experiences, restraining own emotions and seeking agreement, this seemed to contribute to delay. However, when the spouse was resourceful by sharing the experience, having knowledge, understanding the severity, being rational and consulting others when needed, this seemed to have a positive influence on the pre-hospital time.

Myocardial Bridge

Science.gov (United States)

... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

Evaluation of a method to determine the myocardial uptake from 123I-BMIPP myocardial SPECT and its significance

International Nuclear Information System (INIS)

Iwase, Mikio; Toriyama, Takayuki; Itou, Masato; Shimao, Ryuichiro; Ikeda, Koshiro; Suzuki, Takeshi; Nobuta, Takaaki; Iida, Akihiko.

1996-01-01

We examined methods of calculating myocardial uptake (TU) of 123 I-BMIPP by SPECT, and compared TU to heart function (ejection fraction (EF), cardiac output (CO), cardiac index (CI)) calculated by left ventriculography. Forty-two patients with acute myocardial infarction were classified into 5 groups; within 1 week (I), from 1 to 2 weeks (II), from 2 weeks to 1.5 months (III), from 1.5 to 3 months (IV) and more than 3 months (V) after percutaneous transluminal coronary angioplasty (PTCA). Chest depth (Tw) was calculated by measuring the thoracic absorption rate of 123 I. In calculating TU, the myocardial count was calculated from short-axis tomograms, and then absorption was corrected using Tw to calculate each value on early-phase image (E) and delay-phase image (D). The influence of lung uptake on myocardial count was only 1.76%. When TU was compared to heart function, there were correlations between group I and group V. Especially in group VD-TU was a significantly correlated with heart function. In heart function CI, but not EF nor CO, was significantly correlated with TU. It was suggested that the correlation between TU and heart function reflected the infarct condition before PTCA in group I, and that the individual difference in recovery of fatty acid metabolism in group V. The significant correlation between D-TU and CI suggests that D-TU reflects heart function and fatty acid metabolism, although TU is influenced by differences in physical status. (author)

A note on trader Sharpe Ratios.

Science.gov (United States)

Coates, John M; Page, Lionel

2009-11-25

Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D), which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

A note on trader Sharpe Ratios.

Directory of Open Access Journals (Sweden)

John M Coates

Full Text Available Traders in the financial world are assessed by the amount of money they make and, increasingly, by the amount of money they make per unit of risk taken, a measure known as the Sharpe Ratio. Little is known about the average Sharpe Ratio among traders, but the Efficient Market Hypothesis suggests that traders, like asset managers, should not outperform the broad market. Here we report the findings of a study conducted in the City of London which shows that a population of experienced traders attain Sharpe Ratios significantly higher than the broad market. To explain this anomaly we examine a surrogate marker of prenatal androgen exposure, the second-to-fourth finger length ratio (2D:4D, which has previously been identified as predicting a trader's long term profitability. We find that it predicts the amount of risk taken by traders but not their Sharpe Ratios. We do, however, find that the traders' Sharpe Ratios increase markedly with the number of years they have traded, a result suggesting that learning plays a role in increasing the returns of traders. Our findings present anomalous data for the Efficient Markets Hypothesis.

Changes in the phase and amplitude images in the rehabilitation phase after myocardial infarction

International Nuclear Information System (INIS)

Csernay, L.; Mester, J.; Vidakovich, T.; Rajtar, M.; Pavics, L.; Szasz, K.

1984-01-01

A studing involving patients with completed myocardial infarction, who underwent a 3-week exercise program at a cardiocirculatory rehabilitation center in Southern Hungary, is described. Infarctions were confirmed by the typical clinical and ECG signs and symptoms as well as by 201-T1 imaging at rest. Patients with normal 201-T1 activity distribution were excluded. Three ECG-gated equilibrium radionuclide studies were performed in each case: The first was done on the first day of rehabilitation (at a mean post-infarction interval of 1.5 months); the second study was scheduled 3 weeks after the first on completion of the exercise program and the last 9 weeks after the first (on an outpatient basis). From April 25, 1983 to September 9, 1983 a total of 25 patients were investigated. Of these, 9 had normal 201-T1 images. Of the remaining 16, 9 showed no significant changes of the phase and amplitude images. In 2 cases dyskinesia was found to have been replaced by akinesia, and in another 3 akinesia was replaced by hypokinesia. By contrast, 2 previously akinetic patients became dyskinetic. We expect to increase our patient material to at least 50 cases by the end of 1983 and would like to present our results, illustrating them by some typical examples. (Author)

Assessment of sharps waste management practices in a referral ...

African Journals Online (AJOL)

hospital (40.8 kg/day) was higher than values reported in district hospitals, but the sharps waste ... Key words: Sharps waste, sharps waste container, overfilled safety box, sharps waste proportion, .... requirements and availability of technology.

Melatonin protects against myocardial hypertrophy induced by lipopolysaccharide.

Science.gov (United States)

Lu, Qi; Yi, Xin; Cheng, Xiang; Sun, Xiaohui; Yang, Xiangjun

2015-04-01

Melatonin is thought to have the ability of antiatherogenic, antioxidant, and vasodilatory. It is not only a promising protective in acute myocardial infarction but is also a useful tool in the treatment of pathological remodeling. However, its role in myocardial hypertrophy remains unclear. In this study, we investigated the protective effects of melatonin on myocardial hypertrophy induced by lipopolysaccharide (LPS) and to identify their precise mechanisms. The cultured myocardial cell was divided into six groups: control group, LPS group, LPS + ethanol (4%), LPS + melatonin (1.5 mg/ml) group, LPS + melatonin (3 mg/ml) group, and LPS + melatonin (6 mg/ml) group. The morphologic change of myocardial cell was observed by inverted phase contrast microscope. The protein level of myocardial cell was measured by Coomassie brilliant blue protein kit. The secretion level of tumor necrosis factor-α (TNF-α) was evaluated by enzyme-linked immunosorbent assay (ELISA). Ca(2+) transient in Fura-2/AM-loaded cells was measured by Till image system. The expression of Ca(2+)/calmodulin-dependent kinase II (CaMKII) and calcineurin (CaN) was measured by Western blot analysis. Our data demonstrated that LPS induced myocardial hypertrophy, promoted the secretion levels of TNF-α, and increased Ca(2+) transient level and the expression of CaMKII and CaN. Administration of melatonin 30 min prior to LPS stimulation dose-dependently attenuated myocardial hypertrophy. In conclusion, the results revealed that melatonin had the potential to protect against myocardial hypertrophy induced by LPS in vitro through downregulation of the TNF-α expression and retains the intracellular Ca(2+) homeostasis.

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)

Abnormal myocardial capillary density in apical hypertrophic cardiomyopathy can be assessed by myocardial contrast echocardiography

International Nuclear Information System (INIS)

Moon, Jeonggeun; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Jang, Yangsoo; Chung, Namsik; Rim, Se-Joong

2010-01-01

Myocardial ischemia and dysfunction can occur in hypertrophic cardiomyopathy (HCM) because of the high muscle-to-blood ratio, even without significant coronary artery disease. Microbubbles reside only in the intravascular space and myocardial video-intensity during systole results mostly from microbubbles within capillaries. The hypothesis explored in the present study was that an abnormal capillary density in apical HCM (ApHCM) can be demonstrated using myocardial contrast echocardiography (MCE). The 56 patients were investigated (31 males, age 58±9 years; 33 ApHCM, 9 hypertensive left ventricular hypertrophy [LVH], 14 controls). MCE was performed with low-mechanical-index power modulation imaging. Tissue Doppler imaging to assess myocardial contractile function was obtained at the mitral annulus (S'), and 99m Tc-MIBI single photon emission computed tomography (SPECT) was also performed. All ApHCM patients exhibited perfusion defects at the hypertrophied segments in the systolic phase during MCE, whereas SPECT showed normal or rather increased perfusion at those sites. The cyclic variation of video-intensity was exaggerated in ApHCM when compared with the LVH or control group (% of [systolic video-intensity]/[diastolic video-intensity]: 33.0±12.3%, 88.3±19.2% and 79.4±13.9%, respectively [P<0.05]). Concurrently, MCE cyclic variation and perfusion defect size were related to decreased S' (P<0.05 for all). A perfusion defect at the hypertrophied segment, representing abnormal myocardial capillary density, was observed in ApHCM patients during MCE. The extent of MCE cyclic variation and the perfusion defect size both correlate with decreased myocardial contractile property in ApHCM. (author)

Myocardial perfusion imaging by digital subtraction angiography

International Nuclear Information System (INIS)

Kadowaki, Hiroyuki; Ishikawa, Kinji; Ogai, Toshihiro; Katori, Ryo

1986-01-01

Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; 1) at the R wave of the electrocardiogram, 2) 100 msec before the R wave, and 3) 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery. In all patients with anterior myocardial infarction, low perfusion was observed at the infarcted portion compared to the non-infarcted myocardium. In patients with inferior myocardial infarction, this low perfusion area was not observed because right coronary angiography was not subjected to DSA in this study. (J.P.N.)

Motion-corrected whole-heart PET-MR for the simultaneous visualisation of coronary artery integrity and myocardial viability: an initial clinical validation.

Science.gov (United States)

Munoz, Camila; Kunze, Karl P; Neji, Radhouene; Vitadello, Teresa; Rischpler, Christoph; Botnar, René M; Nekolla, Stephan G; Prieto, Claudia

2018-05-12

Cardiac PET-MR has shown potential for the comprehensive assessment of coronary heart disease. However, image degradation due to physiological motion remains a challenge that could hinder the adoption of this technology in clinical practice. The purpose of this study was to validate a recently proposed respiratory motion-corrected PET-MR framework for the simultaneous visualisation of myocardial viability ( 18 F-FDG PET) and coronary artery anatomy (coronary MR angiography, CMRA) in patients with chronic total occlusion (CTO). A cohort of 14 patients was scanned with the proposed PET-CMRA framework. PET and CMRA images were reconstructed with and without the proposed motion correction approach for comparison purposes. Metrics of image quality including visible vessel length and sharpness were obtained for CMRA for both the right and left anterior descending coronary arteries (RCA, LAD), and relative increase in 18 F-FDG PET signal after motion correction for standard 17-segment polar maps was computed. Resulting coronary anatomy by CMRA and myocardial integrity by PET were visually compared against X-ray angiography and conventional Late Gadolinium Enhancement (LGE) MRI, respectively. Motion correction increased CMRA visible vessel length by 49.9% and 32.6% (RCA, LAD) and vessel sharpness by 12.3% and 18.9% (RCA, LAD) on average compared to uncorrected images. Coronary lumen delineation on motion-corrected CMRA images was in good agreement with X-ray angiography findings. For PET, motion correction resulted in an average 8% increase in 18 F-FDG signal in the inferior and inferolateral segments of the myocardial wall. An improved delineation of myocardial viability defects and reduced noise in the 18 F-FDG PET images was observed, improving correspondence to subendocardial LGE-MRI findings compared to uncorrected images. The feasibility of the PET-CMRA framework for simultaneous cardiac PET-MR imaging in a short and predictable scan time (~11 min) has been

Impact of right-ventricular apical pacing on the optimal left-ventricular lead positions measured by phase analysis of SPECT myocardial perfusion imaging

International Nuclear Information System (INIS)

Hung, Guang-Uei; Huang, Jin-Long; Lin, Wan-Yu; Tsai, Shih-Chung; Wang, Kuo-Yang; Chen, Shih-Ann; Lloyd, Michael S.; Chen, Ji

2014-01-01

The use of SPECT phase analysis to optimize left-ventricular (LV) lead positions for cardiac resynchronization therapy (CRT) was performed at baseline, but CRT works as simultaneous right ventricular (RV) and LV pacing. The aim of this study was to assess the impact of RV apical (RVA) pacing on optimal LV lead positions measured by SPECT phase analysis. This study prospectively enrolled 46 patients. Two SPECT myocardial perfusion scans were acquired under sinus rhythm with complete left bundle branch block and RVA pacing, respectively, following a single injection of 99m Tc-sestamibi. LV dyssynchrony parameters and optimal LV lead positions were measured by the phase analysis technique and then compared between the two scans. The LV dyssynchrony parameters were significantly larger with RVA pacing than with sinus rhythm (p ∝0.01). In 39 of the 46 patients, the optimal LV lead positions were the same between RVA pacing and sinus rhythm (kappa = 0.861). In 6 of the remaining 7 patients, the optimal LV lead positions were along the same radial direction, but RVA pacing shifted the optimal LV lead positions toward the base. The optimal LV lead positions measured by SPECT phase analysis were consistent, no matter whether the SPECT images were acquired under sinus rhythm or RVA pacing. In some patients, RVA pacing shifted the optimal LV lead positions toward the base. This study supports the use of baseline SPECT myocardial perfusion imaging to optimize LV lead positions to increase CRT efficacy. (orig.)

Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

International Nuclear Information System (INIS)

Chang, Meng-Chu; Peng, Hsu-Hsia; Wu, Ming-Ting; Weng, Ken-Pen; Su, Mao-Yuan; Menza, Marius; Huang, Hung-Chieh

2018-01-01

We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

Left ventricular regional myocardial motion and twist function in repaired tetralogy of Fallot evaluated by magnetic resonance tissue phase mapping

Energy Technology Data Exchange (ETDEWEB)

Chang, Meng-Chu; Peng, Hsu-Hsia [National Tsing Hua University, Department of Biomedical Engineering and Environmental Sciences, Hsinchu (China); Wu, Ming-Ting [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China); National Yang-Ming University, Faculty of Medicine, Taipei (China); Weng, Ken-Pen [National Yang-Ming University, Faculty of Medicine, Taipei (China); Kaohsiung Veterans General Hospital, Department of Pediatrics, Kaohsiung (China); Shu-Zen Junior College of Medicine and Management, Department of Physical Therapy, Kaohsiung (China); Su, Mao-Yuan [National Taiwan University Hospital, Department of Medical Imaging, Taipei (China); Menza, Marius [Medical Center University of Freiburg, Faculty of Medicine, University of Freiburg, Department of Radiology, Medical Physics, Freiburg (Germany); Huang, Hung-Chieh [Kaohsiung Veterans General Hospital, Department of Radiology, Kaohsiung (China)

2018-01-15

We aimed to characterise regional myocardial motion and twist function in the left ventricles (LV) in patients with repaired tetralogy of Fallot (rTOF) and preserved LV global function. We recruited 47 rTOF patients and 38 age-matched normal volunteers. Tissue phase mapping (TPM) was performed for evaluating the LV myocardial velocity in longitudinal, radial, and circumferential (Vz, Vr, and VOe) directions in basal, middle, and apical slices. The VOe peak-to-peak (PTP) during systolic phases, the rotation angle of each slice, and VOe inconsistency were computed for evaluating LV twist function and VOe dyssynchrony. As compared to the controls, the rTOF patients presented decreased RV ejection fraction (RVEF) (p = 0.002) and preserved global LV ejection fraction (LVEF). They also demonstrated decreased systolic and diastolic Vz in several LV segments and higher diastolic Vr in the septum (all p < 0.05). A lower VOe PTP, higher VOe inconsistency, and reduced peak net rotation angle (all p < 0.05) were observed. The aforementioned indices demonstrated an altered LV twist function in rTOF patients in an early disease stage. MR TPM could provide information about early abnormalities of LV regional motion and twist function in rTOF patients with preserved LV global function. (orig.)

Sharp spatially constrained inversion

DEFF Research Database (Denmark)

Vignoli, Giulio G.; Fiandaca, Gianluca G.; Christiansen, Anders Vest C A.V.C.

2013-01-01

We present sharp reconstruction of multi-layer models using a spatially constrained inversion with minimum gradient support regularization. In particular, its application to airborne electromagnetic data is discussed. Airborne surveys produce extremely large datasets, traditionally inverted...... by using smoothly varying 1D models. Smoothness is a result of the regularization constraints applied to address the inversion ill-posedness. The standard Occam-type regularized multi-layer inversion produces results where boundaries between layers are smeared. The sharp regularization overcomes...... inversions are compared against classical smooth results and available boreholes. With the focusing approach, the obtained blocky results agree with the underlying geology and allow for easier interpretation by the end-user....

Effect of collateral circulation on myocardial protection in patients with acute myocardial infarction. Comparison of technetium-99m-tetrofosmin myocardial single photon emission computed tomography and coronary angiography

International Nuclear Information System (INIS)

Yoshida, Michi; Kondo, Makoto; Abe, Yoshiteru; Kubota, Tomoyuki; Matsuoka, Ryota; Araki, Makoto; Tanio, Hitoshi; Doyama, Kiyoshi

2006-01-01

Evaluation of myocardial blood flow from collateral vessels into the infarct area has been estimated by coronary angiography. In patients with acute myocardial infarction with Thrombolysis in Myocardial Infarction (TIMI) 0 flow, myocardial tracer uptake on single photon emission computed tomography (SPECT) images can predict the collateral blood flow in the infarct area if technetium (Tc)-99m-tetrofosmin was administered before recanalization. The present study investigated whether collateral blood flow evaluated by myocardial scintigraphy is a good predictor of myocardial salvage in patients with acute myocardial infarction. The study group consisted of 30 patients (mean age 65±14 years, 23 males, 7 females) with first acute myocardial infarction and coronary angiography evidence of total occlusion (TIMI 0) within 12 hr after the onset. All patients had one vessel disease related to infarction and TIMI 3 flow after percutaneous coronary intervention (PCI). Tc-99m-tetrofosmin was injected intravenously before the PCI. The regional severity score index (RSSI) was obtained from SPECT using the 17 segment method with the four-point scoring system. Myocardial viability was evaluated by the RSSI obtained from thallium-glucose-insulin infusion SPECT after 1 week and regional wall motion score index obtained from echocardiography during the chronic phase. The patients were divided into two groups according to the angiographic collateral finding. There were no differences in RSSI on thallium-glucose-insulin SPECT and regional wall motion score between the good collateral group (n=8) and poor collateral group (n=22). Myocardial Tc-99m-tetrofosmin RSSI was similar in these groups. On the other hand, the patients were divided according to Tc-99m-tetrofosmin scintigraphic evaluation before PCI. RSSI on thallium-glucose-insulin SPECT was significantly greater (0.7±0.5 vs 1.5±0.4, p<0.01) and regional wall motion score was significantly less (1.46±0.50 vs 2.08±0.78, p<0

Sharps injury reduction using a sharps container with enhanced engineering: a 28 hospital nonrandomized intervention and cohort study.

Science.gov (United States)

Grimmond, Terry; Bylund, Suzann; Anglea, Candace; Beeke, Lou; Callahan, Angela; Christiansen, Erik; Flewelling, Kelly; McIntosh, Kathleen; Richter, Kay; Vitale, Monica

2010-12-01

The decrease in reported sharps injuries (SI) in the United States has markedly slowed. Additional devices and strategies need investigation. Sharps containers are associated with SI, and more than 90% of these injuries are related to container design. This study addresses the hypothesis that containers with enhanced engineering can reduce SI. In a before/after intervention study from 2006 to 2008, we examined the impact of conversion to a sharps container with enhanced engineering (the Device) on SI categories in 14 Ascension Health hospitals (study group). The Device's safety features included large horizontal aperture, sensitive counterbalanced door, large atrium, and passive overfill prevention. Study group results were also compared with a control cohort of 14 contemporaneous size-matched, Ascension Health hospitals (control group). The Device was associated with significant reductions in after-procedure (-30%), disposal-related (-57%), and container-associated (-81%) SI in the study group. No significant reductions occurred in container-associated sharps injuries in the control group. Hospitals using the Device had significantly fewer total SI than control hospitals. Enhanced aperture design can significantly reduce container-associated sharps injuries. Other factors contributing to reduced injuries may include 1-hand deposit, safe closure, hand restriction, and preassembly. These results, from a country where sharps safety devices are widespread, are particularly applicable to countries where safety devices are not extensively used. Copyright © 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

Stress-induced myocardial ischemia is associated with early post-stress left ventricular mechanical dyssynchrony as assessed by phase analysis of {sup 201}Tl gated SPECT myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Chen, Chien-Cheng; Shen, Thau-Yun [Show Chwan Memorial Hospital, Department of Cardiology, Changhua (China); Chang, Ming-Che [Changhua Christian Hospital, Department of Nuclear Medicine, Changhua (China); Hung, Guang-Uei [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China); Chen, Wan-Chen [Chang Bing Show Chwan Memorial Hospital, Department of Nuclear Medicine, Changhua (China); Kao, Chia-Hung [China Medical University, Department of Biomedical Imaging and Radiological Science, Taichung (China); Chen, Ji [Emory University School of Medicine, Department of Radiology and Imaging Sciences, Atlanta, GA (United States)

2012-12-15

In {sup 201}Tl SPECT myocardial perfusion imaging (MPI) data are acquired shortly after the stress injection to assess early post-stress left ventricle (LV) function. The purpose of this study was to use {sup 201}Tl SPECT MPI to investigate whether stress-induced myocardial ischemia is associated with LV mechanical dyssynchrony. Enrolled in the study were 75 patients who were referred for dipyridamole stress and rest {sup 201}Tl gated SPECT MPI. The early post-stress scan was started 5 min after injection, and followed by the rest scan 4 h later. The patients were divided into three groups: ischemia group (N = 25, summed stress score, SSS, {>=}5, summed rest score, SRS, <5), infarct group (N = 16, SSS {>=}5, SRS {>=}5) and normal group (N = 34, SSS <5, SRS <5). LV dyssynchrony parameters were calculated by phase analysis, and compared between the stress and rest images. In the ischemia group, LV dyssynchrony was significantly larger during stress than during rest. On the contrary, LV dyssynchrony during stress was significantly smaller than during rest in the normal and infarct groups. LV dyssynchrony during rest was significantly larger in the infarct group than in the normal and ischemia groups. There were no significant differences in LV dyssynchrony during rest between the normal and ischemia groups. Stress-induced myocardial ischemia caused dyssynchronous contraction in the ischemic region, leading to a deterioration in LV synchrony. Normal myocardium had more synchronous contraction during stress. The different dyssynchrony pattern between ischemic and normal myocardium early post-stress may aid the diagnosis of coronary artery disease using {sup 201}Tl gated SPECT MPI. (orig.)

Acoustic streaming of a sharp edge.

Science.gov (United States)

Ovchinnikov, Mikhail; Zhou, Jianbo; Yalamanchili, Satish

2014-07-01

Anomalous acoustic streaming is observed emanating from sharp edges of solid bodies that are vibrating in fluids. The streaming velocities can be orders of magnitude higher than expected from the Rayleigh streaming at similar amplitudes of vibration. Acoustic velocity of fluid relative to a solid body diverges at a sharp edge, giving rise to a localized time-independent body force acting on the fluid. This force results in a formation of a localized jet. Two-dimensional numerical simulations are performed to predict acoustic streaming for low amplitude vibration using two methods: (1) Steady-state solution utilizing perturbation theory and (2) direct transient solution of the Navier-Stokes equations. Both analyses agree with each other and correctly predict the streaming of a sharp-edged vibrating blade measured experimentally. The origin of the streaming can be attributed to the centrifugal force of the acoustic fluid flow around a sharp edge. The dependence of this acoustic streaming on frequency and velocity is examined using dimensional analysis. The dependence law is devised and confirmed by numerical simulations.

77 FR 56647 - Lisa Jean Sharp: Debarment Order

Science.gov (United States)

2012-09-13

... Act (the FD&C Act) permanently debarring Lisa Jean Sharp from providing services in any capacity to a...&C Act. Ms. Sharp was given notice of the proposed permanent debarment and an opportunity to request... drug product under the FD&C Act. The factual basis for this conviction is as follows: Ms. Sharp was the...

Assessment of Sharp Injuries among Cameroonian Dental ...

African Journals Online (AJOL)

2010-07-10

Jul 10, 2010 ... prophylaxis practice and methods of sharps disposal. Results ... training on guidelines adherence, safe recapping and disposal systems. Abstract ... of sharps in oral healthcare delivery and restricted nar- row field of surgery ...

Anomalous optical behavior of biological media: modifying the optical window of myocardial tissues

Science.gov (United States)

Splinter, Robert; Raja, M. Yasin A.; Svenson, Robert H.

1996-05-01

In medical experimental and clinical treatment modalities of light, laser photocoagulation of ventricular tachycardia amongst others, the success of the application relies on whether or not the procedure operates in the optical window of the light-tissue interaction. The optical window of biological tissues can be determined by spectral scans of the optical properties. Optical anomalies may result from the irradiance, the wavelength, or from the tissue composition itself. The transmission of cw Nd:YAG laser light on myocardial tissue showed a nonlinearity in the transmission curve at approximately 3 kW/mm2 irradiance. The total attenuation coefficient dropped sharp from 1.03 plus or minus 0.04 mm-1 to 0.73 plus or minus 0.05 mm-1 at this point in the curve. On the other hand, aneurysm tissue has a highly organized fiber structure, which serves as light-guides, since the transmission of light along the length of the collagen fibers is approximately 50% higher than the transmission perpendicular to the fiber orientation. In addition, changes in optical properties due to tissue phase changes also influence the penetration depth. These phenomena can be utilized to manipulate the optical penetration to an advantage.

Simultaneous quantification of porcine myocardial adenine nucleotides and creatine phosphate by ion-pair reverse-phase high-performance liquid chromatography

International Nuclear Information System (INIS)

Cordis, G.A.; Das, D.K.

1987-01-01

In order to follow the energy metabolism and the levels of high-energy phosphate compounds in porcine myocardium subjected to ischemic insult, it was necessary to develop a high-performance liquid chromatography (HPLC) method where creatine phosphate (CP) and the adenine nucleotides could be measured simultaneously in a single run. Currently available ion-pair reverse-phase HPLC methods require a separate injection with a change in wavelength and mobile phase in order to measure the creatine phosphate, while baseline separation of AMP is lacking. The ion-exchange HPLC method includes a simultaneous determination, but the baseline drifts due to the gradient and baseline separation of AMP is not achieved. In the following ion-pair reverse-phase HPLC method, simultaneous measurements of porcine myocardial adenine nucleotides and creatine phosphate were achieved along with a stable baseline and homogeneous baseline separation of each measured compound, allowing accurate quantification

Variational reconstruction using subdivision surfaces with continuous sharpness control

Institute of Scientific and Technical Information of China (English)

Xiaoqun Wu; Jianmin Zheng; Yiyu Cai; Haisheng Li

2017-01-01

We present a variational method for subdivision surface reconstruction from a noisy dense mesh.A new set of subdivision rules with continuous sharpness control is introduced into Loop subdivision for better modeling subdivision surface features such as semi-sharp creases,creases,and corners.The key idea is to assign a sharpness value to each edge of the control mesh to continuously control the surface features.Based on the new subdivision rules,a variational model with L1 norm is formulated to find the control mesh and the corresponding sharpness values of the subdivision surface that best fits the input mesh.An iterative solver based on the augmented Lagrangian method and particle swarm optimization is used to solve the resulting non-linear,non-differentiable optimization problem.Our experimental results show that our method can handle meshes well with sharp/semi-sharp features and noise.

MANAGEMENT OF DIABETES IN ACUTE MYOCARDIAL INFARCTION IN CELJE GENERAL HOSPITAL IN 1999

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Gregor Veninšek

2001-12-01

Full Text Available Background. DIGAMI study showed that intrahospital mortality and mortality at one year after myocardial infarction can be significantly reduced in diabetics treated in acute phase of myocardial infarction by GI infusion and afterwards for at least three months with intensive insulin treatment. Mortality can be reduced for more than 50% in a subgroup of patients younger than 70 years, without congestive heart failure, with first myocardial infarction, not treated with insulin or digitalis. In this perspective we reviewed treatment of diabetics with acute myocardial infarction in 1999 in Celje General Hospital.Methods. We reviewed documentation of treatment of all diabetics with acute myocardial infarction treated in Celje General Hospital in 1999. We collected data on number of newly discovered diabetes, on previous treatment of diabetes, on treatment of diabetes during hospitalization and at discharge, on drugs used for treatment of diabetes and on mortality during hospitalization.Results. Diabetics presented 20% of all patients with acute myocardial infarction treated in Celje General Hospital in 1999. None of patients received GI infusion, none had intensively managed blood sugar. 24% of patients were treated with sulfonylureas in acute phase of myocardial infarction. 33% of patients were discharged from hospital with insulin therapy. Intrahospital mortality was 9%, comparable with patients without diabetes.Conclusions. In 1999 was intrahospital treatment of diabetics with acute myocardial infarction in Celje General Hospital successful as their intrahospital mortality equaled non-diabetics. Treatment of diabetes itself, during hospitalization and after discharge, on the other hand, in 1999 had not been up to date according to results of recent studies. In our opinion, it is mandatory for diabetologist to make part of the team that treats diabetic with acute myocardial infarction

Three-dimension structure of ventricular myocardial fibers after myocardial infarction

Directory of Open Access Journals (Sweden)

Li Libin

2010-11-01

Full Text Available Abstract Background To explore the pathological changes of three-dimension structure of ventricular myocardial fibers after anterior myocardial infarction in dog heart. Methods Fourteen acute anterior myocardial infarction models were made from healthy dogs (mean weight 17.6 ± 2.5 kg. Six out of 14 dogs with old myocardial infarction were sacrificed, and their hearts were harvested after they survived the acute anterior myocardial infarction for 3 months. Each heart was dissected into ventricular myocardial band (VMB, morphological characters in infarction region were observed, and infarct size percents in descending segment and ascending segment were calculated. Results Six dog hearts were successfully dissected into VMB. Uncorresponding damages in myocardial fibers of descending segment and ascending segment were found in apical circle in anterior wall infarction. Infarct size percent in the ascending segment was significantly larger than that in the descending segment (23.36 ± 3.15 (SD vs 30.69 ± 2.40%, P = 0.0033; the long axis of infarction area was perpendicular to the orientation of myocardial fibers in ascending segment; however, the long axis of the infarction area was parallel with the orientation of myocardial fibers in descending segment. Conclusions We found that damages were different in both morphology and size in ascending segment and descending segment in heart with myocardial infarction. This may provide an important insight for us to understand the mechanism of heart failure following coronary artery diseases.

The Sharp Lepton Quandary: Reasonable cautions

International Nuclear Information System (INIS)

Griffin, J.J.

1996-02-01

Surprisingly, the new APEX experiment designed to measure a definitive invariant mass distribution of the sharp pairs previously reported in similar heavy ion studies reports null results. Although it asserts no direct conflict with any data reported by EPOS/I, the APEX report nevertheless seems to have encouraged the view that the earlier (EPOS/I) observations were erroneous, and by extrapolation, that the whole (e + e - ) Puzzle data set can be dismissed as an unfortunate set of physically meaningless statistical fluctuations. We wish here to argue that such sweeping judgments should be postponed, on the grounds that (1) the published APEX analysis of their data is self-inconsistent, and can therefore sustain no valid inference about the EPOS/I data; (2) the data which supports the occurrence of sharp (e + e - ) pairs is much more extensive than the EPOS/I data, so that the APEX surprise must be considered as one episode in a much longer struggle finally to settle the question of whether these weak signals are significant or not; (3) a qualitative phenomenology exists which can organize the whole range of data of the Sharp Lepton Problem, and which suggests that (4) certain low energy (and low cost) experiments ought to be explored for their creation of sharp pairs; as follows: the study of pairs emitted following scattering of few MeV electron and positron beams from neutral U and Th atoms, and the study of pairs emitted following the resonant absorption of photons of 1.5 to 2.0 MeV on U and Th atoms. We first present a brief data-oriented history of the Sharp Lepton Problem, to show that no single unexpected null result can provide an adequate basis for rejecting the great range and quantity of data which evidences the occurrence of sharp pairs. We then consider the Quadronium Composite Particle Scenario for these processes, and its Quantum Electrodynamical implications, in support of the above recommendations

Spacecraft Health Automated Reasoning Prototype (SHARP): The fiscal year 1989 SHARP portability evaluations task for NASA Solar System Exploration Division's Voyager project

Science.gov (United States)

Atkinson, David J.; Doyle, Richard J.; James, Mark L.; Kaufman, Tim; Martin, R. Gaius

1990-01-01

A Spacecraft Health Automated Reasoning Prototype (SHARP) portability study is presented. Some specific progress is described on the portability studies, plans for technology transfer, and potential applications of SHARP and related artificial intelligence technology to telescience operations. The application of SHARP to Voyager telecommunications was a proof-of-capability demonstration of artificial intelligence as applied to the problem of real time monitoring functions in planetary mission operations. An overview of the design and functional description of the SHARP system is also presented as it was applied to Voyager.

Clinical usefulness of T1-201 myocardial scintigraphy and diastolic phase index by gated cardiac blood pool imaging in patients with hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Ohmine, Hiromi; Nishimura, Tsunehiko; Hayashida, Kohhei; Uehara, Toshiisa; Kozuka, Takahiro

1984-01-01

Tl-201 myocardial scintigraphy and gated cardiac blood pool imaging with Tc-99m were performed at rest in 24 hypertrophic cardiomyopathy (HCM) and 11 normal subjects. Based on visual analysis of Tl-201 myocardial scintigraphies, patients with HCM were subdivided into the following four groups; type I: non-obstructive, type II: obstructive, type III: asymmetric septal hypertrophy, type IV: apical hypertrophy. Characteristic myocardial hypertrophy of each group was also confirmed from the profile curves of circumferential analysis. First third filling fraction (1/3 FF) and mean first third filling rate (1/3 FRm) were obtained from gated cardiac blood pool imaging. As compaired with the normal subjects, 1/3 FF was not so sensitive for the detection of left ventricular hypertrophy. Mean+-S.D. of 1.3 FRm were 1.96+-0.56/sec (normal group), 1.30+-0.44/sec (typ e I), 1.18+-0.63/sec (type II), 1.17+-0.14/sec (type III), and 1.26+-0.03/sec (type IV). We considered that 1/3 FRm was a useful diastolic phase index in the diagnosis of HCM. (author)

Applicability of myocardial perfusion scintigraphy in the evaluation of cardiac synchronization

Energy Technology Data Exchange (ETDEWEB)

Reis, Christiane Cigagna Wiefels; Nascimento, Erivelton Alessandro do; Dias, Fernanda Baptista Ribeiro; Ribeiro, Mario Luiz; Wanderley, Annelise Passos Bispo; Batista, Layanara Albino; Nunes, Thais Helena Peixoto; Mesquita, Claudio Tinoco, E-mail: chriswreis@gmail.com [Universidade Federal Fluminense (UFF), Niterói, RJ (Brazil). Hospital Universitário Antônio Pedro

2017-07-15

To systematically assess the literature on the applicability of myocardial perfusion scintigraphy with phase analysis in the investigation of cardiac dyssynchrony and in the selection of patients for cardiac resynchronization therapy (CRT), manuscripts published on the PubMed database over the past five years have been reviewed. The following MeSH terms were used: heart failure, left ventricular, dyssynchrony, gated-SPECT, phase analysis and resynchronization therapy. Altogether, 99 manuscripts were included for discussion. Speckle-tracking echocardiography is still widely used in the evaluation of dyssynchrony, but the advent of myocardial perfusion scintigraphy with the phase analysis technique has been gaining ground, as besides being operator independent, it can evaluate myocardial viability in the same test. Its use became more widespread in patients with left bundle branch block, with recommendation of CRT. Phase analysis also allows evaluating, in a highly reproducible way, the last ventricular segment to contract, hence allowing the best positioning of the CRT electrode. Knowing that the presence, location and extent of fibrosis in the left ventricle, associated with dyssynchrony are determinants of response to resynchronization therapy, GATED- SPECT can provide this information in a single test and in a reproducible and accurate way. Phase histogram offers several parameters that provide greater sensitivity and specificity to the method. It seems that the technique is able to add value both in the selection and in the evaluation of response of patients eligible to CRT. Further studies are being conducted to demonstrate its clinical applicability. (author)

Myocardial infarction

International Nuclear Information System (INIS)

Ando, Jyoji; Yasuda, Hisakazu; Miyamoto, Atsushi; Kobayashi, Tsuyoshi

1980-01-01

sup(99m)Tc-pyrophosphate (PYP) scintigraphy and 201 Tl myocardial scintigraphy were utilized for the diagnoses of the presence, the region, and the extent of myocardial infarction. Exercise 201 Tl myocardial scintigrams and exercise radionuclide ventriculography were utilized for diagnosis of coronary artery lesions in angina pectoris. Radionuclide ventriculography was used to investigate effects of coronary artery lesions on cardiac function and hemodynamics. In order to select adequate treatments for myocardial infarction and estimate the prognosis, it was necessary to detect the presence, the region, and the extent of acute myocardial infarction and to investigate effects of partial infarction on hemodynamics by using radionuclide imaging. Exercise myocardial scintigraphy could be carried out noninvasively and repeatedly for diagnosis of coronal artery disease. Therefore, this method could be applied widely. It was possible to use this method as a screening test of coronary artery diseases for the diagnoses of asymptomatic patients who showed ST changes in ECG, the patients with cardiac neurosis and the patency after a reconstructive surgery of coronary artery. (Tsunoda, M.)

Deciphering the role of CA1 inhibitory circuits in sharp wave-ripple complexes.

Science.gov (United States)

Cutsuridis, Vassilis; Taxidis, Jiannis

2013-01-01

Sharp wave-ripples (SWRs) are population oscillatory patterns in hippocampal LFPs during deep sleep and immobility, involved in the replay of memories acquired during wakefulness. SWRs have been extensively studied, but their exact generation mechanism is still unknown. A computational model has suggested that fast perisomatic inhibition may generate the high frequency ripples (~200 Hz). Another model showed how replay of memories can be controlled by various classes of inhibitory interneurons targeting specific parts of pyramidal cells (PC) and firing at particular SWR phases. Optogenetic studies revealed new roles for interneuronal classes and rich dynamic interplays between them, shedding new light in their potential role in SWRs. Here, we integrate these findings in a conceptual model of how dendritic and somatic inhibition may collectively contribute to the SWR generation. We suggest that sharp wave excitation and basket cell (BC) recurrent inhibition synchronises BC spiking in ripple frequencies. This rhythm is imposed on bistratified cells which prevent pyramidal bursting. Axo-axonic and stratum lacunosum/moleculare interneurons are silenced by inhibitory inputs originating in the medial septum. PCs receiving rippling inhibition in both dendritic and perisomatic areas and excitation in their apical dendrites, exhibit sparse ripple phase-locked spiking.

Scintigraphy for the detection of myocardial damage in the indeterminate form of Chagas disease

International Nuclear Information System (INIS)

Pedroso, Enio Roberto Pietra; Rezende, Nilton Alves de

2010-01-01

Background: non-invasive cardiological methods have been used for the identification of myocardial damage in Chagas disease. Objective: to verify whether the rest/stress myocardial perfusion scintigraphy is able to identify early myocardial damage in the indeterminate form of Chagas disease. Methods: eighteen patients with the indeterminate form of Chagas Disease and the same number of normal controls, paired by sex and age, underwent rest/stress myocardial scintigraphy using sestamibi-99mTc, aiming at detecting early cardiac damage. Results: the results did not show perfusion or ventricular function defects in patients at the indeterminate phase of Chagas disease and in the normal controls, except for a patient who presented signs of ventricular dysfunction in the myocardial perfusion scintigraphy with electrocardiographic gating. Conclusion: the results of this study, considering the small sample size, showed that the rest/stress myocardial scintigraphy using sestamibi-99mTc is not an effective method to detect early myocardial alterations in the indeterminate form of Chagas disease (author)

Scintigraphy for the detection of myocardial damage in the indeterminate form of Chagas disease

Energy Technology Data Exchange (ETDEWEB)

Pedroso, Enio Roberto Pietra; Rezende, Nilton Alves de, E-mail: narezende@terra.com.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Medicina; Abuhid, Ivana Moura [Instituto de Medicina Nuclear e Diagnostico Molecular, Belo Horizonte, MG (Brazil)

2010-07-15

Background: non-invasive cardiological methods have been used for the identification of myocardial damage in Chagas disease. Objective: to verify whether the rest/stress myocardial perfusion scintigraphy is able to identify early myocardial damage in the indeterminate form of Chagas disease. Methods: eighteen patients with the indeterminate form of Chagas Disease and the same number of normal controls, paired by sex and age, underwent rest/stress myocardial scintigraphy using sestamibi-99mTc, aiming at detecting early cardiac damage. Results: the results did not show perfusion or ventricular function defects in patients at the indeterminate phase of Chagas disease and in the normal controls, except for a patient who presented signs of ventricular dysfunction in the myocardial perfusion scintigraphy with electrocardiographic gating. Conclusion: the results of this study, considering the small sample size, showed that the rest/stress myocardial scintigraphy using sestamibi-99mTc is not an effective method to detect early myocardial alterations in the indeterminate form of Chagas disease (author)

An alternative window upon the GSI sharp lepton problem

International Nuclear Information System (INIS)

Griffin, J.J.

1997-10-01

Two major heavy ion studies of the GSI ''(e + e - )-Puzzle'' have ended in stalemate: APEX reports no evidence, but its data show a peak near 800 keV. EPOS/II cannot reproduce its own results,and leans towards random fluctuations as the explanation of sharp pair lines. (But one EPOS/II report shows evidence for a peak at an EPOS/I line energy, 610 keV, and under selection conditions the same as EPOSII's.) It is clear that these latest heavy ion studies, designed to settle once and for all the question of sharp pairs, have failed to fulfill that goal. Attention must now turn towards the sharp electron lines reported by Sakai et al. and others in collisions of few MeV beta decay positrons on U and Th atoms. In the Q 0 Scenario of the Sharp Lepton Problem these arise from the same source as the GSI pairs. Verification of Sakai's 100 mb cross section for such sharp electrons in collisions of few MeV electrons (or positrons) upon U or Th atoms would confirm this new experimental window upon the Sharp Lepton Problem. These relatively simple experiments, which are both inexpensive and reproducible (as their heavy ion counterparts are not), promise a less ponderous pace for the study of these questions. On the other hand, they require a challenging combination of proficiencies to measure a nuclear sized cross section in an atomic physics environment. The authors review briefly the diverse history (and especially the most recent developments) of the Sharp Lepton Problem, and outline how the Quadronium Scenario provides it with a unifying conceptual framework. That discussion points clearly towards the experimental study of sharp leptons and sharp pairs from few MeV (lepton+ATOM) and (photon+ATOM) processes as the appropriate next step towards either verifying the earlier results or precluding them

Study of thallium scintigraphy for myocardial infarction performed within 72 hours of attack

Energy Technology Data Exchange (ETDEWEB)

Setsuda, Koichi; Tomita, Yoshifumi; Takayama, Morimasa (Nippon Medical School, Tokyo)

1983-11-01

In 40 cases undergoing /sup 201/Tl myocardial scanning within 72 hours of attack of myocardial infarction, a significant correlation was found between the infarct size determined by myocardial scanning and the size of the infarction estimated on the basis of ECG findings and serum enzymes. The group with high pulmonary capillary wedge pressure was the group with low Tl scores. The group showing dyskinesis and aneurysm in left ventriculography showed low Tl scores and a significant correlation between the ejection fraction calculated from left ventriculograms and the Tl score. The above date indicate that /sup 201/Tl myocardial scanning in the acute phase after attack of infarction reflects the infarction size and cardiac function.

Sharp Gronwall-Bellman type integral inequalities with delay

Directory of Open Access Journals (Sweden)

István Győri

2016-11-01

Full Text Available Various attempts have been made to give an upper bound for the solutions of the delayed version of the Gronwall-Bellman integral inequality, but the obtained estimations are not sharp. In this paper a new approach is presented to get sharp estimations for the nonnegative solutions of the considered delayed inequalities. The results are based on the idea of the generalized characteristic inequality. Our method gives sharp estimation, and therefore the results are more exact than the earlier ones.

Improving acute and long-term myocardial infarction care : bridging the gap between science and practice

NARCIS (Netherlands)

Liem, Su-San

2009-01-01

The main topic of this thesis was the design, implementation and subsequent evaluation of an all-phases integrated care program for patients with acute myocardial infarction: the MISSION! protocol. The aim of MISSION! was to improve daily care for patients with an acute myocardial infarction by

Myocardial Bridging

Directory of Open Access Journals (Sweden)

Shi-Min Yuan

2016-02-01

Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

Clinical study on the time courses of serum myosin light chain I levels in patients with acute myocardial infarction

International Nuclear Information System (INIS)

Nakanishi, Masako; Saiki, Yasuhiko; Ui, Kazuyo

1992-01-01

Changes of serum myosin light chain I (Myosin LCI) concentrations and creatine kinase (CK) activities were serially measured in 23 patients with acute myocardial infarction. Intracoronary thrombolysis was performed in 14 patients (ICT group) while the remaining 9 patients were treated in the conventional manner (non ICT group). The relationships between the maximum levels of serum Myosin LCI or CK and a myocardial infarct size index or left ventricular function were evaluated in 18 patients. The myocardial infarct size index was determined by 201 Tl myocardial scintigrams performed in the chronic phase. Multiple peaks of Myosin LCI were observed in 64% (9/14) of the ICT group and the first peak in 6 of these patients appeared much earlier in the same time as CK peak than in the non-ICT group, while multiple peaks were seen only in one case in the non-ICT group. The infarct size index by 201 Tl myocardial SPECT correlated with maximum Myosin LCI levels (r=0.88, p<0.001, n=10) and CK activities (r=0.67, p<0.05, n=10). These results indicate that the measurement of serum Myosin LCI is very useful for estimating the extent of myocardial damage and suggest that myocardial degeneration occurs at a very early phase of myocardial infarction. (author)

Fasa Registry on Acute Myocardial Infarction (FaRMI: Feasibility Study and Pilot Phase Results.

Directory of Open Access Journals (Sweden)

Ehsan Bahramali

Full Text Available Myocardial infarction (MI is the leading cause of death in Iran. Every attempt to improve treatment patterns and patient outcomes needs a surveillance system to both consider the efficacy and safety measures. Fasa Registry on Myocardial Infarction (FaRMI is the first population-based registry for acute MI in Iran targeted to provide meticulous description of patients' characteristics, to explore the management patterns of these patients, to discover the degree of adherence to the practice guidelines, and to investigate the determinants of poor in-hospital and later outcomes.A diagnosis of acute MI (type I, II and III was made upon the accepted criteria by the attending cardiologists and types IV and V MI were excluded. Two registrar nurses gathered data on demographics, place of residence and ethnicity, past medical history, risk factors, and the clinical course. Management patterns in the pre-hospital setting, during the hospital stay and at the discharge time were recorded. Routine laboratory results and cardiac biomarkers on three consecutive days were registered.pilot phase included the first 95 patients, 63.5% of whom were men and 31.5% were women. With a mean age of 62.89±13.75 years among participants, the rate of premature MI was 31.8%. ST segment elevation MI accounted for 68.2% cases and inferior wall was the most prevalent region involved followed by anterior and posterior walls.Obtained data on the characteristics of patients suffering an MI event revealed the major determinants of delay in initiation of therapies and contributors of poor outcome. Completeness of data was guaranteed upon involvement of multiple checkpoints and data quality was secured by means of automatic validation processes in addition to weekly physicians' roundups.Execution of FaRMI in the form presented is feasible and it will build up a comprehensive population-based registry for MI in the region.

Heterogeneous sharpness for cross-spectral face recognition

Science.gov (United States)

Cao, Zhicheng; Schmid, Natalia A.

2017-05-01

Matching images acquired in different electromagnetic bands remains a challenging problem. An example of this type of comparison is matching active or passive infrared (IR) against a gallery of visible face images, known as cross-spectral face recognition. Among many unsolved issues is the one of quality disparity of the heterogeneous images. Images acquired in different spectral bands are of unequal image quality due to distinct imaging mechanism, standoff distances, or imaging environment, etc. To reduce the effect of quality disparity on the recognition performance, one can manipulate images to either improve the quality of poor-quality images or to degrade the high-quality images to the level of the quality of their heterogeneous counterparts. To estimate the level of discrepancy in quality of two heterogeneous images a quality metric such as image sharpness is needed. It provides a guidance in how much quality improvement or degradation is appropriate. In this work we consider sharpness as a relative measure of heterogeneous image quality. We propose a generalized definition of sharpness by first achieving image quality parity and then finding and building a relationship between the image quality of two heterogeneous images. Therefore, the new sharpness metric is named heterogeneous sharpness. Image quality parity is achieved by experimentally finding the optimal cross-spectral face recognition performance where quality of the heterogeneous images is varied using a Gaussian smoothing function with different standard deviation. This relationship is established using two models; one of them involves a regression model and the other involves a neural network. To train, test and validate the model, we use composite operators developed in our lab to extract features from heterogeneous face images and use the sharpness metric to evaluate the face image quality within each band. Images from three different spectral bands visible light, near infrared, and short

Surface-Wave Pulse Routing around Sharp Right Angles

Science.gov (United States)

Gao, Z.; Xu, H.; Gao, F.; Zhang, Y.; Luo, Y.; Zhang, B.

2018-04-01

Surface-plasmon polaritons (SPPs), or localized electromagnetic surface waves propagating on a metal-dielectric interface, are deemed promising information carriers for future subwavelength terahertz and optical photonic circuitry. However, surface waves fundamentally suffer from scattering loss when encountering sharp corners in routing and interconnection of photonic signals. Previous approaches enabling scattering-free surface-wave guidance around sharp corners are limited to either volumetric waveguide environments or extremely narrow bandwidth, being unable to guide a surface-wave pulse (SPP wave packet) on an on-chip platform. Here, in a surface-wave band-gap crystal implemented on a single metal surface, we demonstrate in time-domain routing a surface-wave pulse around multiple sharp right angles without perceptible scattering. Our work not only offers a solution to on-chip surface-wave pulse routing along an arbitrary path, but it also provides spatiotemporal information on the interplay between surface-wave pulses and sharp corners, both of which are desirable in developing high-performance large-scale integrated photonic circuits.

The sharp edge: a frequent radiographic sign in neonatal pneumothorax

International Nuclear Information System (INIS)

Oestreich, A.E.

1987-01-01

The sharp edge sign, an unusually sharply defined silhouette of the heart and/or hemidiaphragm on frontal radiographs of the supine neonate, has been valuable in the initial recognition of pneumothorax. In a prospective study of 50 neonatal pneumothoraces, a sharp edge sign was present on the initial pneumothorax film 49 times. In seven of these, only the hemidiaphragm showed a sharp edge, while the heart margin was superimposed on the vertebral column. Greater awareness of the sharp edge sign would promote earlier recognition of neonatal pneumothorax. 6 refs.; 3 figs

Assessment of myocardial viability by exercise stress myocardial tomography with 201Tl

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa

1992-01-01

Exercise stress (Ex) and redistribution (RD) myocardial tomography with Tl-201 has been widely used for evaluating myocardial viability. But recent studies have demonstrated that reinjection (ReI) study following RD study is necessary for detecting reversible ischemic myocardium. On the other hand, decreased myocardial washout of Tl-201 after Ex is an indicator of myocardial ischemia. So we have studied the usefulness of myocardial Tl-201 washout rate (WOR) for the evaluation of myocardial viability by comparing it with ReI images. Ex and RD myocardial tomographies were obtained immediately after Ex and 3 hours later. After RD study a small amount of Tl-201 was injected and ReI imaging was repeated. We studied 64 myocardial segments (in 58 patients with coronary artery disease) in which Ex-induced perfusion defects persisted in RD images. According to the changes of perfusion defects between Ex, RD and ReI images, they were classified into 3 types: Type I; perfusion defect on the RD image was identical to ReI image (75%). Type I was divided into 2 subgroups whether perfusion defect at Ex was unchanged (Ia, 42%) or improved (Ib, 33%) on the RD image. Type II; perfusion defect at Ex was reduced on the RD image and it improved furthermore at ReI image (17%). Type III; perfusion defect was the same at Ex and RD but it was reduced on the ReI image (8%). WOR less than 30% was defined as abnormal when Ex heart rate exceeded 120 bpm and lung-myocardial Tl-201 uptake ratio was less than 0.45. The differentiation between Type Ia and Type III is of great importance. History of myocardial infarction, effort angina and Ex induced ST depression could not differentiate these 2 groups. WOR abnormality was observed in all of Type III, but WOR was normal in Type Ia. In conclusion, WOR abnormality in Ex-RD myocardial imaging is useful for evaluating myocardial viability. ReI imaging is necessary for the precise evaluation of viable muscle mass and for inadequate Ex. (author)

Sharp tipped plastic hollow microneedle array by microinjection moulding

Science.gov (United States)

Yung, K. L.; Xu, Yan; Kang, Chunlei; Liu, H.; Tam, K. F.; Ko, S. M.; Kwan, F. Y.; Lee, Thomas M. H.

2012-01-01

A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost.

Sharp tipped plastic hollow microneedle array by microinjection moulding

International Nuclear Information System (INIS)

Yung, K L; Xu, Yan; Kang, Chunlei; Liu, H; Tam, K F; Ko, S M; Kwan, F Y; Lee, Thomas M H

2012-01-01

A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost. (paper)

Different Causes of Death in Patients with Myocardial Infarction Type 1, Type 2, and Myocardial Injury.

Science.gov (United States)

Lambrecht, Sascha; Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S; Gerke, Oke; Hosbond, Susanne; Diederichsen, Axel C P; Thygesen, Kristian; Mickley, Hans

2018-05-01

Data outlining the mortality and the causes of death in patients with type 1 myocardial infarction, type 2 myocardial infarction, and those with myocardial injury are limited. During a 1-year period from January 2010 to January 2011, all hospitalized patients who had cardiac troponin I measured on clinical indication were prospectively studied. Patients with at least one cardiac troponin I value >30 ng/L underwent case ascertainment and individual evaluation by an experienced adjudication committee. Patients were classified as having type 1 myocardial infarction, type 2 myocardial infarction, or myocardial injury according to the criteria of the universal definition of myocardial infarction. Follow-up was ensured until December 31, 2014. Data on mortality and causes of death were obtained from the Danish Civil Registration System and the Danish Register of Causes of Death. Overall, 3762 consecutive patients were followed for a mean of 3.2 years (interquartile range 1.3-3.6 years). All-cause mortality differed significantly among categories: Type 1 myocardial infarction 31.7%, type 2 myocardial infarction 62.2%, myocardial injury 58.7%, and 22.2% in patients with nonelevated troponin values (log-rank test; P causes, vs 42.6% in patients with type 2 myocardial infarction (P = .015) and 41.2% in those with myocardial injury (P causes of death did not differ substantially between patients with type 2 myocardial infarction and those with myocardial injury. Patients with type 2 myocardial infarction and myocardial injury exhibit a significantly higher long-term mortality compared with patients with type 1 myocardial infarction . However, most patients with type 1 myocardial infarction die from cardiovascular causes in contrast to patients with type 2 myocardial infarction and myocardial injury, in whom noncardiovascular causes of death predominate. Copyright © 2018 Elsevier Inc. All rights reserved.

Myocardial accumulation of a dopamine D[sub 2] receptor-binding radioligand, 2'-iodospiperone

Energy Technology Data Exchange (ETDEWEB)

Saji, Hideo; Yonekura, Yoshiharu; Tanahashi, Kiyoko; Iida, Yasuhiko; Iwasaki, Yasushi; Magata, Yasuhiro; Konishi, Junji; Yokoyama, Akira [Kyoto Univ. (Japan). Faculty of Medicine

1993-08-01

[sup 125]I-iodospiperone (2'-ISP), which has a high and selective affinity for dopamine D[sub 2] receptors, produced a high myocardial accumulation of radioactivity in the early phase after intravenous injection into mice. A human scintigraphic study also showed that the myocardium was clearly visualized soon after intravenous injection of the tracer. Analysis of the myocardial homogenate obtained from mice showed that [sup 125]I-2'-ISP was metabolically stable and was taken up by the myocardium in its intact form. Administration of spiperone significantly reduced the myocardial uptake of [sup 125]I-2'-ISP in mice. Treatment with haloperidol and (+) butaclamol, which have a high affinity for dopamine D[sub 2] receptors, also tended to reduce the myocardial uptake of radioactivity, while (-)-butaclamol, which has no affinity for dopamine D[sub 2] receptors, caused no change in uptake. These findings suggest that the myocardial accumulation of 2'-ISP occurred in association with dopamine D[sub 2] (DA[sub 2]) receptors. (author).

Myocardial imaging. Coxsackie myocarditis

Energy Technology Data Exchange (ETDEWEB)

Wells, R.G.; Ruskin, J.A.; Sty, J.R.

1986-09-01

A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

Myocardial imaging. Coxsackie myocarditis

International Nuclear Information System (INIS)

Wells, R.G.; Ruskin, J.A.; Sty, J.R.

1986-01-01

A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1

A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

International Nuclear Information System (INIS)

Liu, Yixun; Summers, Ronald M.; Yao, Jianhua; Liu, Songtao; Sibley, Christopher T.; Bluemke, David A.; Nacif, Marcelo S.

2013-01-01

Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use

A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images

Energy Technology Data Exchange (ETDEWEB)

Liu, Yixun; Summers, Ronald M.; Yao, Jianhua, E-mail: JYao@cc.nih.gov [Clinical Image Processing Service, Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Liu, Songtao; Sibley, Christopher T.; Bluemke, David A. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 and Molecular Biomedical Imaging Laboratory, National Institute of Biomedical Imaging and Bioengineering, NIH Clinical Center, Bethesda, Maryland 20892 (United States); Nacif, Marcelo S. [Radiology and Imaging Sciences, NIH Clinical Center, Bethesda, Maryland 20892-1182 (United States)

2013-10-15

Purpose: Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image. Methods: To deal with this difficulty, the authors present a complete ECVF measurement framework including a point-guided myocardial modeling, a deformable model-based myocardium segmentation, nonrigid registration of pre- and post-CT, and ECVF calculation. Results: The proposed method was evaluated on 20 patients by two observers. Compared to the manually delineated reference segmentations, the accuracy of our segmentation in terms of true positive volume fraction (TPVF), false positive volume fraction (FPVF), and average surface distance (ASD), were 92.18% ± 3.52%, 0.31% ± 0.10%, 0.69 ± 0.14 mm, respectively. The interobserver variability measured by concordance correlation coefficient regarding TPVF, FPVF, and ASD were 0.95, 0.90, 0.94, respectively, demonstrating excellent agreement. Bland-Altman method showed 95% limits of agreement between ECVF at CT and ECVF at MR. Conclusions: The proposed framework demonstrates its efficiency, accuracy, and noninvasiveness in ECVF measurement and dramatically advances the ECVF at cardiac CT toward its clinical use.

Epitaxial growth of topological insulator Bi{sub 2}Se{sub 3} film on Si(111) with atomically sharp interface

Energy Technology Data Exchange (ETDEWEB)

Bansal, Namrata [Department of Electrical and Computer Engineering, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Kim, Yong Seung [Graphene Research Institute, Sejong University, Seoul 143-747 (Korea, Republic of); Edrey, Eliav; Brahlek, Matthew; Horibe, Yoichi [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Iida, Keiko; Tanimura, Makoto [Research Department, Nissan Arc, Ltd. Yokosuka, Kanagawa 237-0061 (Japan); Li Guohong; Feng Tian; Lee, Hang-Dong; Gustafsson, Torgny; Andrei, Eva [Department of Physics and Astronomy, Rutgers, State University of New Jersey, Piscataway, NJ 08854 (United States); Oh, Seongshik, E-mail: ohsean@physics.rutgers.edu [Department of Physics and Astronomy, Rutgers, the State University of New Jersey, Piscataway, NJ 08854 (United States)

2011-10-31

Atomically sharp epitaxial growth of Bi{sub 2}Se{sub 3} films is achieved on Si(111) substrate with molecular beam epitaxy. Two-step growth process is found to be a key to achieve interfacial-layer-free epitaxial Bi{sub 2}Se{sub 3} films on Si substrates. With a single-step high temperature growth, second phase clusters are formed at an early stage. On the other hand, with low temperature growth, the film tends to be disordered even in the absence of a second phase. With a low temperature initial growth followed by a high temperature growth, second-phase-free atomically sharp interface is obtained between Bi{sub 2}Se{sub 3} and Si substrate, as verified by reflection high energy electron diffraction (RHEED), transmission electron microscopy (TEM) and X-ray diffraction. The lattice constant of Bi{sub 2}Se{sub 3} is observed to relax to its bulk value during the first quintuple layer according to RHEED analysis, implying the absence of strain from the substrate. TEM shows a fully epitaxial structure of Bi{sub 2}Se{sub 3} film down to the first quintuple layer without any second phase or an amorphous layer.

Study progress of cardiac MRI technology in assessment of myocardial viability after myocardial infarction

International Nuclear Information System (INIS)

Wang Jing; Zhang Hao

2013-01-01

Acute myocardial infarction (AMI) is one of the most common diseases that cause disability and death around the world. Correctly and effectively assessing the myocardial viability after myocardial infarction can reduce the disabled rate and mortality rate. At present, many methods could be used to assess myocardial viability. The cardiac magnetic resonance imaging (CMR) technology has a lot of advantages compared to other methods. In this paper, we reviewed the research progress of CMR in assessment of myocardial viability after myocardial infarction, and compared CMR with other technologies. (authors)

The diagnosis of silent myocardial ischemia. Motion-Frozen (or morphing) myocardial perfusion imaging.

Science.gov (United States)

Chang, Cheng; Ye, Bo; Xie, Wenhui; Zhang, Daoliang; Lei, Bei; Ye, Xiaodan

2016-01-01

Silent myocardial ischemia is typically defined as objective evidence of myocardial ischemia in patients without subjective ischemia symptoms. Currently, coronary artery angiography is the gold standard for diagnosis of asymptomatic coronary artery disease (CAD). Computed tomography coronary angiography (CTCA) can visually demonstrate the morphology, trend and extent of coronary stenosis and is commonly used in clinical screening of CAD. Myocardial perfusion imaging can be used not only to identify whether anatomical stenosis causes myocardial dysfunction, but to also assess the risk stratification and prognosis of myocardial disease (MD). Myocardial perfusion imaging using morphing combined with CTCA can simultaneously show the relationship between CAD and myocardial ischemia from an anatomical and functional aspect. This allows earlier diagnosis of asymptomatic CAD myocardial ischemia, accurate identification of the culprit vessels, and could prevent unnecessary interventional therapy. The 1-day dobutamine stress/resting met-hod is also one of the methods used. The combination of CTCA and the morphing technique can provide anatomical and functional information on coronary arteries at the same time, significantly improving the diagnostic sensitivity, specificity, and accuracy of MD.

Sharp Efficiency for Vector Equilibrium Problems on Banach Spaces

Directory of Open Access Journals (Sweden)

Si-Huan Li

2013-01-01

Full Text Available The concept of sharp efficient solution for vector equilibrium problems on Banach spaces is proposed. Moreover, the Fermat rules for local efficient solutions of vector equilibrium problems are extended to the sharp efficient solutions by means of the Clarke generalized differentiation and the normal cone. As applications, some necessary optimality conditions and sufficient optimality conditions for local sharp efficient solutions of a vector optimization problem with an abstract constraint and a vector variational inequality are obtained, respectively.

Screening for silent myocardial ischemia caseof diabetics : interest of myocardial perfusion scintigraphy

International Nuclear Information System (INIS)

Bahri, Haifa

2007-01-01

Silent myocardial ischemia is a major cause of morbidity and mortality in diabetic patients. Its diagnosis by noninvasive means such as myocardial SPECT would improve the management of these patients. The purpose of this study is to assess the frequency of silent myocardial ischemia in asymptomatic diabetics and their evolution. As a result, the myocardial SPECT is a reliable tool for screening for silent myocardial ischemia in diabetic patients. Its prognostic value allows to stratify the cardiac risk and guide therapeutic management. Its integration into a screening strategy in Tunisia seems limited by its low availability and cost. The latter could be reduced by better patient selection.

Sharp foreign body ingestion by a young girl

African Journals Online (AJOL)

Riyadh Mohamad Hasan

2017-06-09

Jun 9, 2017 ... Sharp foreign body ingestion by a young girl. Riyadh Mohamad Hasan. University of Baghdad ... ray imaging and retrieved with the aid of C-arm fluoroscope at a laparotomy. Her postoperative period ... In our patient the foreign bodies were long sharp ones (sewing needles). Foreign body ingestion can be ...

Myocardial perfusion imaging with Technetium-99m Sestamibi and Thallium-201. Results of the phase III clinical trial

International Nuclear Information System (INIS)

Giering, L.; Haber, S.; Joseph, J.L.; Neacy, W.

1998-01-01

Full text: Technetium-99m-Sestamibi (MIBI) has been compared to 201 TI and coronary angiography in a large Phase III clinical trial to assess diagnostic accuracy. Exercise and rest planar (P) and SPECT (S) MIBI, and exercise and redistribution thallium-201 studies were performed in 150 healthy volunteers and 396 patients (379 males; mean age 51.3 years). Prior myocardial infarction was present in 50% of the patients. Sensitivity and specificity for angiographically defined cardiovascular diseases - CAD (>70% stenosis) for planar imaging was 90.3% and 81.3% for MIBI and 91.6% and 50.0% for 201 TI. Agreement was 88.7% MIBI and 84.0% for 201 TI. For SPECT imaging, sensitivity and specificity were 95.1% and 46.0% for MIBI and 92.3% and 39.7% for 201 TI. Agreement was 80.0% for MIBI and 76.1% for 201 TI. Tomographic normality rates were 91.4% and 92.9% for MIBI and 201 TI. Agreement for characterisation of defect type by MIBI and 201 TI SPECT was 82.5%. In females, sensitivity was comparable for both agents. Specificity of MIBI planar and SPECT imaging was higher then for 201 TI (P: 90.9% v. 66.7%; S: 76.2% v. 61.9%). The improved imaging characteristics of MIBI results in better diagnostic confidence when interpreting myocardial perfusion studies especially in women and obese patients

Periodontitis and myocardial hypertrophy.

Science.gov (United States)

Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

2017-04-01

There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

Time-clustering behavior of sharp fluctuation sequences in Chinese stock markets

International Nuclear Information System (INIS)

Yuan Ying; Zhuang Xintian; Liu Zhiying; Huang Weiqiang

2012-01-01

Sharp fluctuations (in particular, extreme fluctuations) of asset prices have a great impact on financial markets and risk management. Therefore, investigating the time dynamics of sharp fluctuation is a challenge in the financial fields. Using two different representations of the sharp fluctuations (inter-event times and series of counts), the time clustering behavior in the sharp fluctuation sequences of stock markets in China is studied with several statistical tools, including coefficient of variation, Allan Factor, Fano Factor as well as R/S (rescaled range) analysis. All of the empirical results indicate that the time dynamics of the sharp fluctuation sequences can be considered as a fractal process with a high degree of time-clusterization of the events. It can help us to get a better understanding of the nature and dynamics of sharp fluctuation of stock price in stock markets.

Knowledge Base Editor (SharpKBE)

Science.gov (United States)

Tikidjian, Raffi; James, Mark; Mackey, Ryan

2007-01-01

The SharpKBE software provides a graphical user interface environment for domain experts to build and manage knowledge base systems. Knowledge bases can be exported/translated to various target languages automatically, including customizable target languages.

Assessment of left ventricular myocardial scar with three-dimensional MRI

International Nuclear Information System (INIS)

Yin Gang; Zhao Shihua; Lu Minjie

2011-01-01

Objective: To assess the value of free-breathing 3D phase sensitive inversion recovery (PSIR) turbo FLASH for demonstrating the left ventricular myocardial scar in patients with myocardial infarction. Methods: Twenty-three patients with myocardial infarction underwent 2D and 3D phase sensitive inversion recovery (PSIR) Turbo FLASH sequences 10-15 minutes after injection of dimeglumine gadopentetate. The image quality, the area, location and volume of hyperenhanced scar were independently assessed by two experienced radiologists. Student's t test or rank sum test and Pearson linear correlation were used for the statistics. Results: There were no significant differences in the overall image quality (2.57± 0.59 vs 2.39±0.66, Z=-0.93, P=0.35), the area (24.48±10.83 vs 29.00±11.56, Z=-1.41, P=0.16) and location (16.78±6.51 vs 18.87±6.76, Z=-1.17, P=0.24) of hyperenhanced scar between 2D and 3D PSIR sequences. The mean volume of hyperenhanced scar was significantly greater in 3D PSIR sequence than that in 2D PSIR sequence [(23.46±10.61) vs (31.65±13.86) cm 3 , t=-2.25, P= 0.03]. There was a good correlation in the volume of hyperenhanced scar between 2D PSIR and 3D PSIR sequences (r=0.940, P 2 =0.883). Conclusion: Free-breathing 3D PSIR Turbo FLASH is a promising new imaging technique for accurate assessment of myocardial scar. (authors)

The clinical application value of myocardial perfusion imaging in evaluating coronary artery myocardial bridge patients with symptoms

International Nuclear Information System (INIS)

Wang Yuetao; Fu Ning; Ding Xuemei; Lu Cunzhi; Zhu Feng; Wang Guanmin; Huang Yijie; Wang Linguang

2008-01-01

Objective: Myocardial bridge is a common inborn coronary artery anomaly, myocardial bridge may be associated with myocardial ischemia. Only a few patients with coronary artery myocardial bridge were evaluated with nuclear medicine techniques. The aim of this study was to investigate the role of nuclear cardiology with myocardial perfusion technique in symptomatic myocardial bridge patients. Methods Nineteen myocardial bridge patients with the symptoms of chest pain and chest distress were analyzed retrospectively. 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion images (both exercise and rest) were performed in all. Imaging results were compared with the results of movement electrocardiogram (ECG) and coronary arteriography. The t test or χ 2 test was used to statistically analyze the data with Stata 7.0 software. Results: Of the 19 patients, 18 patients had myocardial bridge locating at the left anterior descending artery, 1 patient at the left anterior descending and left circumflex artery, the mean angiographic systolic occlusion within the myocardial bridge was (65.4 ± 22.1)%. Of these 19 patients, Exercise-rest 99 Tc m -MIBI myocardial perfusion imaging defined positive myocardial ischemia in 10 and negative in 9 patients. Of the 10 patients with 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia, 8 had reversible radioactive defect of partial anterior wall and (or) apex, 1 had reversible defect of post lateral wall and post septal wall, and 1 had reversible defect of inferior wall. The positive predictive value of myocardial perfusion imaging was 52.6% (10/19), which was higher than movement ECG [21.1% (4/19), χ 2 = 4.07, P 99 Tc m -MIBI myocardial periusion imaging defined myocardial ischemia. Six cases with Grade II stenosis, two were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial ischemia. Eight cases with Grade III stenosis, seven were 99 Tc m -MIBI myocardial perfusion imaging defined myocardial

Clinical Characteristics and Outcomes of Patients with Myocardial Infarction, Myocardial Injury, and Nonelevated Troponins

DEFF Research Database (Denmark)

Sarkisian, Laura; Saaby, Lotte; Poulsen, Tina S

2016-01-01

BACKGROUND: Cardiac troponins have emerged as the preferred biomarkers for detecting myocardial necrosis and diagnosing myocardial infarction. However, current cardiac troponin assays do not discriminate between ischemic and nonischemic causes of myocardial cell death. Thus, when an increased...... troponin value is encountered in the absence of obvious myocardial ischemia, a careful search for other clinical conditions is crucial. METHODS: In 2010 to 2011, we prospectively studied hospitalized patients who had cardiac troponin I measured on clinical indication. An acute myocardial infarction...... was diagnosed in cases of a cardiac troponin I increase or decrease pattern with at least 1 value >30 ng/L (99th percentile) together with myocardial ischemia. Myocardial injury was defined as cardiac troponin I values >30 ng/L, but without signs or symptoms indicating overt cardiac ischemia. Patients with peak...

SHARP {Summer High School Apprenticeship Research Program}

Science.gov (United States)

Glasco, Deborah (Technical Monitor)

2002-01-01

The Year 2002 was another successful year for SHARP. Even after 22 years of SHARP, the Program continues to grow. There were 12 NASA Field Installations with a total of 210 apprentices who participated in the summer 2002 Program supported by 215 mentors in the fields of science and engineering. The apprentices were chosen from a pool of 1,379 applicants. This was a record year for applications exceeding the previous year by over 60%. For the second consecutive year, the number of female participants exceeded the number of males with 53% female and 47% male participants in the program. The main thrust of our recruiting efforts is still focused on underrepresented populations; especially African American, Hispanic, and Native American. At the conclusion of the summer program, most SHARP Apprentices indicated on the EDCATS that they would be interested in pursuing careers in Aerospace (56.2%) while the second largest career choice was a job at NASA (45.7%). The smallest number (11.9%) were interested in careers in the government. The table of responses is listed in the Appendix. Once again this year we were fortunate in that the SHARP COTR, Ms. Deborah Glasco, gained the support of MURED funding sources at NASA to fully fund additional apprentices and boost the number of apprentices to 210.

GATED SPECT TO EVALUATE LEFT VENTRICULAR MYOCARDIAL PERFUSION, FUNCTION AND DYSSYNCHRONY FOR RESYNCHRONIZATION THERAPY

Directory of Open Access Journals (Sweden)

E.N. Ostroumov

2009-01-01

Full Text Available The study included 15 consecutive patients with heart failure and substantial LV dyssynchrony undergoing CRT. Clinical and phase analysis of gated myocardial perfusion SPECT assessed at baseline, after 2–3 days and after 3–4 months of CRT. The results demonstrated inversely relationship between the response to CRT and the nonviable myocardium. Evaluation of myocardial viability is necessary to considered in the selection process for CRT.

Left ventricular diastolic dyssynchrony assessed with phase analysis of gated myocardial perfusion SPECT: a comparison with tissue Doppler imaging

International Nuclear Information System (INIS)

Boogers, Mark J.; Veltman, Caroline E.; Chen, Ji; Garcia, Ernest V.; Bommel, Rutger J. van; Mooyaart, Eline A.Q.; Wall, Ernst E. van der; Schalij, Martin J.; Bax, Jeroen J.; Delgado, Victoria; Younis, Imad Al; Hiel, Bernies van der; Dibbets-Schneider, Petra

2011-01-01

The aim of the current study was to evaluate the feasibility of phase analysis on gated myocardial perfusion SPECT (GMPS) for the assessment of left ventricular (LV) diastolic dyssynchrony in a head-to-head comparison with tissue Doppler imaging (TDI). The population consisted of patients with end-stage heart failure of New York Heart Association functional class III or IV with a reduced LV ejection fraction of ≤35%. LV diastolic dyssynchrony was calculated using TDI as the maximal time delay between early peak diastolic velocities of two opposing left ventricle walls (diastolic mechanical delay). Significant LV diastolic dyssynchrony was defined as a diastolic mechanical delay of >55 ms on TDI. Furthermore, phase analysis on GMPS was performed to evaluate LV diastolic dyssynchrony; diastolic phase standard deviation (SD) and histogram bandwidth (HBW) were used as markers of LV diastolic dyssynchrony. A total of 150 patients (114 men, mean age 66.0 ± 10.4 years) with end-stage heart failure were enrolled. Both diastolic phase SD (r = 0.81, p 55 ms) showed significantly larger diastolic phase SD (68.1 ± 13.4 vs. 40.7 ± 14.0 , p < 0.01) and diastolic HBW (230.6 ± 54.3 vs. 129.0 ± 55.6 , p < 0.01) as compared to patients without LV diastolic dyssynchrony on TDI (≤55 ms). Finally, phase analysis on GMPS showed a good intra- and interobserver reproducibility for the determination of diastolic phase SD (ICC 0.97 and 0.88) and diastolic HBW (ICC 0.98 and 0.93). Phase analysis on GMPS showed good correlations with TDI for the assessment of LV diastolic dyssynchrony. (orig.)

Clinical aspects of coronary heart diseases without myocardial infarction and in the chronic infarction phase

International Nuclear Information System (INIS)

Kober, G.

1984-01-01

Reductions in coronary vessel diameters of more than 50% are usually caused by atherosclerosis, seldom by predominant spasme. They can lead via an inadequate myocardial perfusion to angina pectoris. Whereas in patients with organic coronary stenoses exertional angina is typical, patients with coronary spasms usually tend to angina at rest. Depending on the symptoms, a stable or unstable angina can be distinguished from the status anginosus and a variant form of angina. During anginal attacks signs of myocardial ischemia can often be seen in the electrocardiogram. This applies to patients with and without earlier myocardial infarctions. When pathologic ECG-changes can already be seen in the ECG at rest, difficulties often arise during evaluation of the exercise-ECG. In those cases, diagnosis can be improved by additional investigations, especially with radionuclear techniques. For a conclusive diagnosis, left heart catheterization and a functional coronary angiography is necessary. Coronary heart disease can be treated either by drug therapy, coronary angioplasty or bypass surgery. The same diagnostic procedures are suitable for the evaluation of a therapeutical success and for primary diagnosis. (orig.) [de

Diagnostic value of exercise induced 18F-FDG myocardial metabolism scintigraphy in myocardial ischemia

International Nuclear Information System (INIS)

Shen Rui; He Zuoxiang; Shi Rongfang; Liu Xiujie; Tian Yueqin; Guo Feng; Wei Hongxing; Wu Yongjian; Qin Xuewen; Gao Runlin

2006-01-01

Objective: To evaluate the feasibility and diagnostic accuracy of exercise induced myocardial imaging with 18 F-fluorodeoxyglucose (FDG) in myocardial ischemia. Methods: Twenty-six patients with known or suspected coronary artery, disease (CAD) and with no prior myocardial infarction underwent simultaneous myocardial perfusion and metabolism imaging following intravenous injection of 99 Tc m -methoxy-isobutylisonitrile ( 99 Tc m -sestamibi) and 18 F-FDG at peak exercise. Subsequently rest perfusion imaging and coronary angiography (CAG) were performed in all patients. Exercise 18 F-FDG myocardial imaging was compared with 99 Tc m -sestamibi imaging and CAG. Results: In 22 patients with ≥50% narrowing over l coronary artery, 18 had perfusion abnormalities (sensitivity 82%), whereas 20 had abnormal myocardial 18 F-FDG uptake (sensitivity 91%, P>0.05). Patients with reversible (12 cases) or partial reversible (3 cases) perfusion abnormalities had increased myocardial 18 F-FDG uptake in abnormal perfusion segments. Compared with CAG, perfusion defect was seen in myocardial segments corresponding to 25 vascular territories of 51 vessels with ≥50% narrowing in 22 patients in 99 Tc m -sestamibi imaging (sensitivity 49%), whereas increased 18 F-FDG uptake was seen in 34 vascular territories (sensitivity 67%, P=0.008). Conclusions: Exercise induced myocardial ischemia can be imaged directly with 18 F-FDG. Combined exercise 18 F-FDG and 99 Tc m -sestamibi imaging provides a better assessment of exercise-induced myocardial ischemia as compared with exercise-rest perfusion imaging. (authors)

The impact of sharps injuries on student nurses: a systematic review.

Science.gov (United States)

Hambridge, Kevin; Nichols, Andrew; Endacott, Ruth

2016-10-27

The purpose of this review was to discover the impact of sharps injuries in the student nurse population. Much is known and reported about sharps injuries in registered nurses, but there has been a lack of published evidence regarding sharps injuries within the student nurse population. A systematic review of nursing, health and psychology databases was conducted. The limits set were publications between 1980 and 2014 in the English language. Studies were identified then, following a rigorous critical and quality appraisal with validated tools, were selected for the systematic review. A total of 40 articles met the inclusion criteria, reporting studies conducted in 18 countries. Psychological and physical impacts of sharps injuries in student nurses were reported, such as fear, anxiety and depression, although these impacts were not quantified using a validated instrument. The impact of sharps injuries can be severe, both psychological and physical. This systematic review shows that further research is needed into this, especially in under-researched areas such as the UK, to establish the impact of sharps injuries within this population. Further research would also aid the education and prevention of this harmful problem. The review also emphasises the psychological issues relating to sharps injuries, the impact these can have on individuals and the support and counselling that student nurses require after injury. These findings highlight the potential psychological issues that can result from sharps injuries in this population.

Radioimmunoassay determination of factor 4 platelets (PF4) in acute myocardial infarction patients

International Nuclear Information System (INIS)

Leon Herrejon, Ma. de L.; Graef S, A.; Altamirano B, P.; Ramos C, M.A.

1985-01-01

From a pathological standpoint an increase in the Factor 4 platelet has been observed in various abnormal states including myocardial infarction, diabetes mellitus, diffuse intravascular coagulation and renal insufficiency among others. Eighty subjects were studied at rest: 40 normal and under no medication, and 40 myocardial infarction patients in the acute phase and with added pathology. All were under the same therapeutic regimen. Results obtained between both groups were statistically significant with a P > 0.01. (author)

Localization and quantification of acute myocardial infarction by myocardial perfusion tomographic imaging

International Nuclear Information System (INIS)

Lin Xiufang; Min Changgeng; Lin Zhihu; Ke Ruoyi

1994-01-01

The authors reported the result of the quantification and localization of 30 clinically confirmed acute myocardial infarction patients in comparison with that of ECG. A left ventricle model was used to correct the area calculated by the method of Bull's eye. The result indicated that the infarction area calculated by the corrected Bull's eye method correlated closely with that determined by the ECG QRS scoring method (r = 0.706, P<0.01). Myocardial infarctions of all 30 patients were detected by both ECG and myocardial perfusion tomographic imaging. The accuracy of localization of myocardial infarction by myocardial perfusion imaging was similar to that of ECG in the anterior wall, anterior septum, anterior lateral and inferior wall, but superior to that of ECG in the apex, posterior lateral, posterior septum, and posterior wall

Classification of myocardial infarction

DEFF Research Database (Denmark)

Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne Elisabeth

2013-01-01

The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...

Direct Evidence that Myocardial Insulin Resistance following Myocardial Ischemia Contributes to Post-Ischemic Heart Failure

Science.gov (United States)

Fu, Feng; Zhao, Kun; Li, Jia; Xu, Jie; Zhang, Yuan; Liu, Chengfeng; Yang, Weidong; Gao, Chao; Li, Jun; Zhang, Haifeng; Li, Yan; Cui, Qin; Wang, Haichang; Tao, Ling; Wang, Jing; Quon, Michael J; Gao, Feng

2015-01-01

A close link between heart failure (HF) and systemic insulin resistance has been well documented, whereas myocardial insulin resistance and its association with HF are inadequately investigated. This study aims to determine the role of myocardial insulin resistance in ischemic HF and its underlying mechanisms. Male Sprague-Dawley rats subjected to myocardial infarction (MI) developed progressive left ventricular dilation with dysfunction and HF at 4 wk post-MI. Of note, myocardial insulin sensitivity was decreased as early as 1 wk after MI, which was accompanied by increased production of myocardial TNF-α. Overexpression of TNF-α in heart mimicked impaired insulin signaling and cardiac dysfunction leading to HF observed after MI. Treatment of rats with a specific TNF-α inhibitor improved myocardial insulin signaling post-MI. Insulin treatment given immediately following MI suppressed myocardial TNF-α production and improved cardiac insulin sensitivity and opposed cardiac dysfunction/remodeling. Moreover, tamoxifen-induced cardiomyocyte-specific insulin receptor knockout mice exhibited aggravated post-ischemic ventricular remodeling and dysfunction compared with controls. In conclusion, MI induces myocardial insulin resistance (without systemic insulin resistance) mediated partly by ischemia-induced myocardial TNF-α overproduction and promotes the development of HF. Our findings underscore the direct and essential role of myocardial insulin signaling in protection against post-ischemic HF. PMID:26659007

End-point sharpness in thermometric titrimetry.

Science.gov (United States)

Tyrrell, H J

1967-07-01

It is shown that the sharpness of an end-point in a thermometric titration where the simple reaction A + B right harpoon over left harpoon AB takes place, depends on Kc(A') where K is the equilibrium constant for the reaction, and c(A') is the total concentration of the titrand (A) in the reaction mixture. The end-point is sharp if, (i) the enthalpy change in the reaction is not negligible, and (ii) Kc(A') > 10(3). This shows that it should, for example, be possible to titrate 0.1 M acid, pK(A) = 10, using a thennometric end-point. Some aspects of thermometric titrimetry when Kc(A') < 10(3) are also considered.

Edge Sharpness Assessment by Parametric Modeling: Application to Magnetic Resonance Imaging.

Science.gov (United States)

Ahmad, R; Ding, Y; Simonetti, O P

2015-05-01

In biomedical imaging, edge sharpness is an important yet often overlooked image quality metric. In this work, a semi-automatic method to quantify edge sharpness in the presence of significant noise is presented with application to magnetic resonance imaging (MRI). The method is based on parametric modeling of image edges. First, an edge map is automatically generated and one or more edges-of-interest (EOI) are manually selected using graphical user interface. Multiple exclusion criteria are then enforced to eliminate edge pixels that are potentially not suitable for sharpness assessment. Second, at each pixel of the EOI, an image intensity profile is read along a small line segment that runs locally normal to the EOI. Third, the profiles corresponding to all EOI pixels are individually fitted with a sigmoid function characterized by four parameters, including one that represents edge sharpness. Last, the distribution of the sharpness parameter is used to quantify edge sharpness. For validation, the method is applied to simulated data as well as MRI data from both phantom imaging and cine imaging experiments. This method allows for fast, quantitative evaluation of edge sharpness even in images with poor signal-to-noise ratio. Although the utility of this method is demonstrated for MRI, it can be adapted for other medical imaging applications.

Tl myocardial SPECT demonstrates importance of collateral circulation in patients with myocardial infarction

International Nuclear Information System (INIS)

Hattori, Fukunori

1997-01-01

The influence of collateral circulation on the preservation of myocardial viability and the efficacy of drug therapy and PTCA were evaluated by exercise 201 Tl myocardial SPECT before and after treatment. Thirty-five patients with a history of myocardial infarction resulting from total or subtotal obstruction of the responsible coronary artery were divided into four groups, according to the method of the treatment and the degree of collateral blood flow. Patients in groups A and B received drug therapy and displayed developed and undeveloped collateral circulation, respectively. Groups C and D received PTCA and displayed developed and undeveloped collateral circulation, respectively. Tl myocardial SPECT was performed before treatment to record the extent of redistribution to the occluded region, the degree of myocardial viability and the nature and extent of the ischemic lesion. In group A, myocardial perfusion improved, although redistribution remained in all cases, while in group B, 4 of 7 cases improved after drug therapy. In group C, myocardial perfusion improved in all cases, and redistribution disappeared in 7 of 12 cases. 5 of 6 cases improved in group D after PTCA. After drug therapy, the %Tl uptake in the infarcted region improved significantly in initial and delayed images of patients in group A. The differences in initial and delayed images in group B before and after drug therapy were not significant. In contrast, groups C and D both registered significant improvement in initial and delayed images after PTCA. The washout rate improved significantly in groups A, C and D after their respective treatments. These results suggest that developed collateral circulation helps to preserve myocardial viability in cases of myocardial infarction. Myocardial perfusion improved after drug therapy in cases with developed collateral circulation, and in patients with developed and undeveloped collateral circulation receiving PTCA. (K.H.)

Myocardial scintigraphy

International Nuclear Information System (INIS)

Bunko, Hisashi; Hisada, Kinichi

1982-01-01

Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome.

Science.gov (United States)

Chen, Chun; Li, Dianfu; Miao, Changqing; Feng, Jianlin; Zhou, Yanli; Cao, Kejiang; Lloyd, Michael S; Chen, Ji

2012-07-01

The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4%) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI.

Positron computed tomography for myocardial uptake of N-13 ammonia in patients with hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Yoshida, Katsuya; Himi, Toshiharu; Imai, Hitoshi; Shukuya, Masaki; Masuda, Yoshiaki; Inagaki, Yoshiaki; Yamasaki, Toshiro; Tateno, Yukio.

1985-01-01

In the present study, positron computed tomography (PCT) was used to evaluate the myocardial uptake of N-13 ammonia in patients with hypertrophic cardiomyopathy (HCM). Eight subjects including two normal persons, four patients with HCM, and two with old myocardial farction (OMI) were selected for the study. N-13 ammonia was administered intravenously as a bolus and, commencing with the tracer injection, serial 30-second PCT scans were performed. The results were summarized as follows: 1. The first scan exhibiting cardiac blood pool images revealed a reduced left ventricular cavity in the HCM subjects. 2. After clearance of N-13 from the cardiopulmonary vasculature, the left ventricular myocardium was clearly visualized and an increased myocardial mass with characteristic morphology was demonstrated in the HCM subjects. 3. Detailed analysis of the time-activity curves of the blood pool and myocardium derived from these serial scan images disclosed two uptake phases in the uptake mode of N-13 ammonia. In the initial phase within three minutes, the myocardial uptake of N-13 was rapid in the normal and OMI subjects, whereas its significant delay was observed in the HCM subjects. This may reflect an abnormal initial extraction of N-13 ammonia in the HCM patients compared with the other subjects. 4. Subsequently, in the second phase, which was characterized by a gradual increase of N-13 in the myocardium, the HCM subjects revealed higher uptake ratios than did the others. This may indicate an increased extraction of metabolites of N-13 ammonia during the second phase. These preliminary results undersore the usefulness of dynamic PCT with N-13 ammonia for the assessment of HCM. (author)

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

International Nuclear Information System (INIS)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E.; El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria; Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke; Kroft, Lucia J.; Younis, Imad Al; Reiber, Johan H.; Scholte, Arthur J.

2013-01-01

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 ± 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS ≥2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p 2 = 20.7) and lesion length (χ 2 = 26.0) to the clinical variables and the visual assessment (χ 2 = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have incremental value over baseline variables and visually assessed significant stenosis. Potentially, QCT can refine assessment of CAD, which may be of potential use for identification of patients with myocardial ischaemia. (orig.)

Myocardial contusion in patients with blunt chest trauma as evaluated by thallium 201 myocardial scintigraphy

International Nuclear Information System (INIS)

Bodin, L.; Rouby, J.J.; Viars, P.

1988-01-01

Fifty five patients suffering from blunt chest trauma were studied to assess the diagnosis of myocardial contusion using thallium 201 myocardial scintigraphy. Thirty-eight patients had consistent scintigraphic defects and were considered to have a myocardial contusion. All patients with scintigraphic defects had paroxysmal arrhythmias and/or ECG abnormalities. Of 38 patients, 32 had localized ST-T segment abnormalities; 29, ST-T segment abnormalities suggesting involvement of the same cardiac area as scintigraphic defects; 21, echocardiographic abnormalities. Sixteen patients had segmental hypokinesia involving the same cardiac area as the scintigraphic defects. Fifteen patients had clinical signs suggestive of myocardial contusion and scintigraphic defects. Almost 70 percent of patients with blunt chest trauma had scintigraphic defects related to areas of myocardial contusion. When thallium 201 myocardial scintigraphy directly showed myocardial lesion, two-dimensional echocardiography and standard ECG detected related functional consequences of cardiac trauma

Exercise induced ST elevation and residual myocardial ischemia in previous myocardial infarction

International Nuclear Information System (INIS)

Shimonagata, Tsuyoshi; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Saito, Muneyasu; Sumiyoshi, Tetsuya

1987-01-01

The purpose of this study was to evaluate the clinical significance of stress induced ST elevation on infarcted area in 65 patients with previous myocardial infarction (single vessel disease) who had stress thallium scan. Stress induced ST changes on infarcted area were compared with quantitative assessment of myocardial ischemia (thallium ischemic score; TIS) and extent of myocardial infarction (defect score; DS) derived from circumferential profile analysis. In patients with previous myocardial infarction in less than 3 month from the onset (n = 36), left ventricular ejection fraction (LVEF) and extent of abnormal LV wall motion were not significantly different between patients with stress induced ST elevation ( ≥ 2 mm, n = 26) and those with stress induced ST elevation ( < 2 mm, n = 10), while, in patients with previous myocardial infarction in more than 3 month (n = 29), patients with stress induced ST elevation ( ≥ 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with ST elevation ( < 2 mm, n = 14). In addition, the former showed significantly higher DS and significantly lower TIS than the latter. In patients with previous myocardial infarction in less than 3 month, patients with ST elevation ( ≥ 2 mm, n = 15) with prominent upright T wave (n = 15) had transient thallium defect in infarcted area in 73 % and they had significantly higher LVEF and TIS than those with ST elevation ( < 2 mm, n = 11). These results indicated that ST elevation in infarcted area reflect different significance according to the recovery of injured myocardium and stress induced ST elevation with prominent upright T wave in infarcted area reflect residual myocardial ischemia in less than 3 month from the onset of myocardial infarction. (author)

Myocardial ischemia in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Lima Filho, Moyses de Oliveira; Figueiredo, Geraldo L.; Simoes, Marcus V.; Pyntia, Antonio O.; Marin Neto, Jose Antonio

2000-01-01

Myocardial ischemia in hypertrophic cardiomyopathy is multifactorial and explains the occurrence of angina, in about 50% of patients. The pathophysiology of myocardial ischemia may be explained by the increase of the ventricular mass and relative paucity of the coronary microcirculation; the elevated ventricular filling pressures and myocardial stiffness causing a compression of the coronary microvessels; the impaired coronary vasodilator flow reserve caused by anatomic and functional abnormalities; and the systolic compression of epicardial vessel (myocardial bridges). Myocardial ischemia must be investigated by perfusion scintigraphic methods since its presence influences the prognosis and has relevant clinical implications for management of patients. Patients with hypertrophic cardiomyopathy and documented myocardial ischemia usually need to undergo invasive coronary angiography to exclude the presence of concomitant atherosclerotic coronary disease. (author)

Multislice coronary computed tomographic angiography in emergency department presentations of unsuspected acute myocardial infarction.

Science.gov (United States)

Hecht, Harvey S; Bhatti, Tandeep

2009-01-01

Coronary computed tomographic angiography (CCTA) is not indicated in the setting of acute myocardial infarction in the emergency department (ED). Nonetheless, acute coronary syndromes may have atypical presentations, and CCTA may be inadvertently performed in this setting. This study was designed to determine the frequency and characteristics of CCTA imaging of unsuspected acute myocardial infarction in the ED. All CCTAs performed in the ED at Lenox Hill Hospital were reviewed for clinical indications and subsequent course; patients with documented acute myocardial infarction were identified. Of the 500 CCTAs performed on ED patients in the Lenox Hill laboratory, 5 patients (1%) were imaged during the initial phase of an unsuspected acute myocardial infarction; in all cases the CCTAs were key to the diagnosis. The imaging characteristics were (1) total or subtotal occlusion and (2) transmural hypodensity in the infarct area. Although acute myocardial infarction on CCTA in ED patients is an infrequent event, proper and prompt recognition is critical for appropriate patient care, particularly as applications to the ED increase.

Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

International Nuclear Information System (INIS)

Jodocy, Daniel; Aglan, Iman; Friedrich, Guy; Mallouhi, Ammar; Pachinger, Otmar; Jaschke, Werner; Feuchtner, Gudrun M.

2010-01-01

Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 ± 6.5 mm; depth, 2.6 ± 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p 50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

Effects of sharp vorticity gradients in two-dimensional hydrodynamic turbulence

DEFF Research Database (Denmark)

Kuznetsov, E.A.; Naulin, Volker; Nielsen, Anders Henry

2007-01-01

The appearance of sharp vorticity gradients in two-dimensional hydrodynamic turbulence and their influence on the turbulent spectra are considered. We have developed the analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together with the ......The appearance of sharp vorticity gradients in two-dimensional hydrodynamic turbulence and their influence on the turbulent spectra are considered. We have developed the analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together...... with the divorticity lines. Compressibility of this mapping can be considered as the main reason for the formation of the sharp vorticity gradients at high Reynolds numbers. For two-dimensional turbulence in the case of strong anisotropy the sharp vorticity gradients can generate spectra which fall off as k−3 at large...

Automated quantitative coronary computed tomography correlates of myocardial ischaemia on gated myocardial perfusion SPECT

Energy Technology Data Exchange (ETDEWEB)

Graaf, Michiel A. de; Boogers, Mark J.; Veltman, Caroline E. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); The Interuniversity Cardiology Institute of The Netherlands, Utrecht (Netherlands); El-Naggar, Heba M.; Bax, Jeroen J.; Delgado, Victoria [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands); Broersen, Alexander; Kitslaar, Pieter H.; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Kroft, Lucia J. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Younis, Imad Al [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands); Reiber, Johan H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical imaging systems B.V., Leiden (Netherlands); Scholte, Arthur J. [Leiden University Medical Center, Department of Cardiology, Leiden (Netherlands)

2013-08-15

Automated software tools have permitted more comprehensive, robust and reproducible quantification of coronary stenosis, plaque burden and plaque location of coronary computed tomography angiography (CTA) data. The association between these quantitative CTA (QCT) parameters and the presence of myocardial ischaemia has not been explored. The aim of the present investigation was to evaluate the association between QCT parameters of coronary artery lesions and the presence of myocardial ischaemia on gated myocardial perfusion single-photon emission CT (SPECT). Included in the study were 40 patients (mean age 58.2 {+-} 10.9 years, 27 men) with known or suspected coronary artery disease (CAD) who had undergone multidetector row CTA and gated myocardial perfusion SPECT within 6 months. From the CTA datasets, vessel-based and lesion-based visual analyses were performed. Consecutively, lesion-based QCT was performed to assess plaque length, plaque burden, percentage lumen area stenosis and remodelling index. Subsequently, the presence of myocardial ischaemia was assessed using the summed difference score (SDS {>=}2) on gated myocardial perfusion SPECT. Myocardial ischaemia was seen in 25 patients (62.5 %) in 37 vascular territories. Quantitatively assessed significant stenosis and quantitatively assessed lesion length were independently associated with myocardial ischaemia (OR 7.72, 95 % CI 2.41-24.7, p < 0.001, and OR 1.07, 95 % CI 1.00-1.45, p = 0.032, respectively) after correcting for clinical variables and visually assessed significant stenosis. The addition of quantitatively assessed significant stenosis ({chi} {sup 2} = 20.7) and lesion length ({chi} {sup 2} = 26.0) to the clinical variables and the visual assessment ({chi} {sup 2} = 5.9) had incremental value in the association with myocardial ischaemia. Coronary lesion length and quantitatively assessed significant stenosis were independently associated with myocardial ischaemia. Both quantitative parameters have

Diagnostic usefulness of the oedema-infarct ratio to differentiate acute from chronic myocardial damage using magnetic resonance imaging

International Nuclear Information System (INIS)

Yamada, Kiyoyasu; Suzuki, Susumu; Kinoshita, Kousuke; Yokouchi, Kazuhiko; Iwata, Hirokazu; Sawada, Ken; Isobe, Satoshi; Ohshima, Satoru; Murohara, Toyoaki; Hirai, Makoto

2012-01-01

To differentiate acute from chronic damage to the myocardium in patients with myocardial infarction (MI) using DE and T2w MR. Short-axis T2w and DE MR images were acquired twice after the onset of MI in 36 patients who successfully underwent emergency coronary revascularisation. The areas of infarct and oedema were measured. The oedema-infarct ratio (O/I) of the left ventricular area was calculated by dividing the oedema by the infarct area. The oedema size on T2w MR was significantly larger than the infarct size on DE MR in the acute phase. Both the oedema size on T2w MR and the infarct size on DE MR in the acute phase were significantly larger than those in the chronic phase. The O/I was significantly greater in the acute phase compared with that in the chronic phase (P < 0.05). An analysis of relative cumulative frequency distributions revealed an O/I of 1.4 as a cut-off value for differentiating acute from chronic myocardial damage with the sensitivity, specificity, and accuracy of 85.1%, 82.7% and 83.9%, respectively. The oedema-infarct ratio may be a useful index in differentiating acute from chronic myocardial damage in patients with MI. (orig.)

Hydrodynamic processes in sharp meander bends and their morphological implications

NARCIS (Netherlands)

Blanckaert, K.

2011-01-01

The migration rate of sharp meander bends exhibits large variance and indicates that some sharply curved bends tend to stabilize. These observations remain unexplained. This paper examines three hydrodynamic processes in sharp bends with fixed banks and discusses their morphological implications:

Evaluation of left ventricular function in patient with old myocardial infarction by 201-thallium myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Kanji; Shimohara, Yasuaki; Ito, Misao; Okada, Keisei [Kure Kyosai Hospital, Hiroshima (Japan); Kodama, Kazunori

1984-08-01

Correlation between the ratio of myocardial defect calculated by 201-thallium myocardial scintigraphy and the left ventricular ejection fraction (LVEF) obtained by gated blood pool scintigraphy and the maximum level of creatine phosphokinase (CPK) was studied in 70 patients with old myocardial infarction. There was a significant correlation between the defect ratio and the LVEF or CPK level in patients with anterior or septal myocardial infarction. In all patients with inferior myocardial infarction in whom no defect was seen, the LVEF was more than 40%. However, no distinct correlation between the defect ratio and the LVEF or CPK level was obtained in cases of inferior myocardial infarction.

Hydrogen Sulfide Donor GYY4137 Protects against Myocardial Fibrosis

Directory of Open Access Journals (Sweden)

Guoliang Meng

2015-01-01

Full Text Available Hydrogen sulfide (H2S is a gasotransmitter which regulates multiple cardiovascular functions. However, the precise roles of H2S in modulating myocardial fibrosis in vivo and cardiac fibroblast proliferation in vitro remain unclear. We investigated the effect of GYY4137, a slow-releasing H2S donor, on myocardial fibrosis. Spontaneously hypertensive rats (SHR were administrated with GYY4137 by intraperitoneal injection daily for 4 weeks. GYY4137 decreased systolic blood pressure and inhibited myocardial fibrosis in SHR as evidenced by improved cardiac collagen volume fraction (CVF in the left ventricle (LV, ratio of perivascular collagen area (PVCA to lumen area (LA in perivascular regions, reduced hydroxyproline concentration, collagen I and III mRNA expression, and cross-linked collagen. GYY4137 also inhibited angiotensin II- (Ang II- induced neonatal rat cardiac fibroblast proliferation, reduced the number of fibroblasts in S phase, decreased collagen I and III mRNA expression and protein synthesis, attenuated oxidative stress, and suppressed α-smooth muscle actin (α-SMA, transforming growth factor-β1 (TGF-β1 expression as well as Smad2 phosphorylation. These results indicate that GYY4137 improves myocardial fibrosis perhaps by a mechanism involving inhibition of oxidative stress, blockade of the TGF-β1/Smad2 signaling pathway, and decrease in α-SMA expression in cardiac fibroblasts.

Assessment of myocardial fatty acid metabolism in patients with angina pectoris and diabetes mellitus using 123I-BMIPP myocardial scintigraphy

International Nuclear Information System (INIS)

Ito, Kazuki; Tanabe, Takuji; Yuba, Tatsuya; Doue, Tomoki; Adachi, Yoshihiko; Katoh, Shuuji; Sugihara, Hiroki; Azuma, Akihiro; Nakagawa, Masao

2001-01-01

We studied the effect of myocardial ischemia and diabetes mellitus (DM) on the myocardial fatty acid metabolism using 123 I-BMIPP myocardial scintigraphy. We performed 123 I-BMIPP myocardial scintigraphy in 50 patients with myocardial ischemia and without DM (AP), in 30 patients with myocardial ischemia and DM (AP+DM), 12 patients with DM and without myocardial ischemia (DM), and in 10 normal subjects (N). Myocardial uptake rate of 123 I-BMIPP was obtained using the time activity curve. Myocardial washout rate of 123 I-BMIPP was calculated using the polar images of early and delayed SPECT images. Myocardial uptake rate of 123 I-BMIPP (%) were AP: 4.9±0.6, AP+DM: 5.5±0.5, DM 5.7±0.5 and N: 5.0±0.4. 123 I-BMIPP myocardial uptake rate was increased in AP+DM and DM. 123 I-BMIPP myocardial washout rate (%) were AP: 30.2±4.3, AP+DM: 24.5±3.9, DM: 16.1±2.8 and N: 19.4±3.2. 123 I-BMIPP myocardial washout rate was increased in AP and AP+DM. 123 I-BMIPP myocardial washout rate was increased particularly in patients with multi-vessels disease. 123 I-BMIPP myocardial washout rate was decreased in DM. The present study suggested that diabetes mellitus increased myocardial fatty acid uptake and decreased myocardial fatty acid washout, and that myocardial ischemia increased myocardial fatty acid washout. (author)

[Overview of sharps injuries among health-care workers].

Science.gov (United States)

Gopar-Nieto, Rodrigo; Juárez-Pérez, Cuauhtémoc Arturo; Cabello-López, Alejandro; Haro-García, Luis Cuauhtémoc; Aguilar-Madrid, Guadalupe

2015-01-01

Sharps injuries are one of the most frequent health-care related accidents. It is estimated globally that 35 million workers are at risk; in Mexico there is no data available for this type of injuries. They are associated with lack of training, instrument and procedure risk, fatigue and stress. The occupational distribution is nurses 45 %, technicians 20 %, doctors 20 % and maintenance workers 5 %. The most commonly associated procedures are injection, venipuncture, suture, and insertion and manipulation of IV catheters. Hepatitis B is the most commonly transmitted agent. Emotional distress is huge as well as the cost of prophylaxis and follow-up. More than half of the injuries are not notified. The most common reasons for not reporting are: the belief that the exposure has low risk of infection, the lack of knowledge of reporting systems and the assumption that it is difficult to notify. Many strategies have been created to reduce the incidence of sharps injuries, such as: identifying the risk of blood exposure, the creation of politics to minimize the risk, the education and training to create a safe workplace, the enhancing of the reporting system, the use of double-gloving and using safety-engineered sharps devices. In many countries these politics have reduced the incidence of sharps injuries as well as the economic burden.

Dynamic 123-I-HDA myocardial scintigraphy: which parameters are useful

International Nuclear Information System (INIS)

Fridrich, L.; Gassner, A.; Sykora, J.; Mostbeck, G.; Vagner, M.; Pichler, M.

1984-01-01

32 patients underwent dynamic myocardial imaging using I-123-HDA at rest. Of these, 12 had undergone coronary angiography including 6 with coronary bypass; 8 were post myocardial infarction, 8 had cardiomyopathies and 6 were normal. As radionuclide ventriculography at rest and on exertion had been done throughout, fatty acid turnover and global as well as regional function data were available for comparison. In contrast to most of the earlier studies which did not go beyond the early phase of tracer kinetics, i.e. the first 40 minutes, and thus seem to be suggestive of a monoexponential pattern, the acquisition time in our study was extended to 90 minutes. In addition, the kinetic profile of the tracer was evaluated both mono-exponentially (early phase) and bi-exponentially. Unlike the 70-minute acquisition time, this provides for a better identification of the late phase. Mono-exponential evaluation showed half-lifes of 20 to 45 minutes. Using the be-exponential method, half-lifes of 5 to 19 minutes were found for the rapid elimination phase. The ratio between the rapid and the slow component of fatty acid elimination was equally determined. Ratios <1.0 sensitively predict the presence of CHD or CMP. In the latter condition the uncorrected early phase already shows a clearly prolonged elimination half-life. Computing the fast tracer elimination half-life alone after allowing for the slow component has sofar not been found to be a clinically useful criterion. (Author)

Occupational exposure to sharps injury among healthcare providers in Ethiopia regional hospitals

NARCIS (Netherlands)

Sharew, Nigussie Tadesse; Mulu, Getaneh Baye; Habtewold, Tesfa Dejenie; Gizachew, Kefyalew Dagne

2017-01-01

BACKGROUND: Sharps injury is a penetrating stab wound from a needle, scalpel, or another sharp object that may result in exposure to blood or other body fluids. According to World Health Organization pooled estimate, the annual incidence of sharps injury in Africa was ranged from 2.10 to 4.68 per

Phase-field model of eutectic growth

International Nuclear Information System (INIS)

Karma, A.

1994-01-01

A phase-field model which describes the solidification of a binary eutectic alloy with a simple symmetric phase diagram is introduced and the sharp-interface limit of this model is explored both analytically and numerically

LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome

International Nuclear Information System (INIS)

Chen, Chun; Li, Dianfu; Miao, Changqing; Zhou, Yanli; Cao, Kejiang; Feng, Jianlin; Lloyd, Michael S.; Chen, Ji

2012-01-01

The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4 %) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p < 0.05). RFA improved LV synchrony in the entire cohort and in the patients with septal APs (p < 0.01). Phase analysis of gated SPECT MPI demonstrated that LV mechanical dyssynchrony can be present in patients with WPW syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI. (orig.)

LV dyssynchrony as assessed by phase analysis of gated SPECT myocardial perfusion imaging in patients with Wolff-Parkinson-White syndrome

Energy Technology Data Exchange (ETDEWEB)

Chen, Chun; Li, Dianfu; Miao, Changqing; Zhou, Yanli; Cao, Kejiang [First Affiliated Hospital of Nanjing Medical University, Department of Cardiology, Nanjing, Jiangsu (China); Feng, Jianlin [First Affiliated Hospital of Nanjing Medical University, Department of Nuclear Medicine, Nanjing, Jiangsu (China); Lloyd, Michael S. [Emory University School of Medicine, Division of Cardiology, Atlanta, GA (United States); Chen, Ji [Emory University School of Medicine, Department of Radiology and Imaging Sciences, Atlanta, GA (United States)

2012-07-15

The purpose of this study was to evaluate left ventricular (LV) mechanical dyssynchrony in patients with Wolff-Parkinson-White (WPW) syndrome pre- and post-radiofrequency catheter ablation (RFA) using phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Forty-five WPW patients were enrolled and had gated SPECT MPI pre- and 2-3 days post-RFA. Electrophysiological study (EPS) was used to locate accessory pathways (APs) and categorize the patients according to the AP locations (septal, left and right free wall). Electrocardiography (ECG) was performed pre- and post-RFA to confirm successful elimination of the APs. Phase analysis of gated SPECT MPI was used to assess LV dyssynchrony pre- and post-RFA. Among the 45 patients, 3 had gating errors, and thus 42 had SPECT phase analysis. Twenty-two patients (52.4 %) had baseline LV dyssynchrony. Baseline LV dyssynchrony was more prominent in the patients with septal APs than in the patients with left or right APs (p < 0.05). RFA improved LV synchrony in the entire cohort and in the patients with septal APs (p < 0.01). Phase analysis of gated SPECT MPI demonstrated that LV mechanical dyssynchrony can be present in patients with WPW syndrome. Septal APs result in the greatest degree of LV mechanical dyssynchrony and afford the most benefit after RFA. This study supports further investigation in the relationship between electrical and mechanical activation using EPS and phase analysis of gated SPECT MPI. (orig.)

Myocardial scintigraphy with thallium-201

Energy Technology Data Exchange (ETDEWEB)

Lichte, H [Zentralkrankenhaus Gauting (Germany, F.R.). Nuklearmedizinische Abt.

1977-04-01

Myocardial scintigraphy with /sup 201/thallium is a non-invasive method for detection of myocardial infarction and coronary heart disease. Redistribution-analysis as a sequential-scintigraphy of an exercise-scan permits to distinguish between myocardial scars and coronary vessel disease.

Myocardial adrenergic nerve activity in valvular diseases assessed by iodine-123-metaiodobenzylguanidine myocardial scintigraphy

International Nuclear Information System (INIS)

Imamura, Yoshihiro; Fukuyama, Takaya

1997-01-01

Iodine-123-metaiodobenzylguanidine (MIBG) imaging was used to assess myocardial adrenergic nerve activity in patients with heart failure. MIBG planar images were obtained in 94 patients. The uptake of MIBG, calculated as the heart-to-mediastinum activity ratio in the immediate image (15 min), showed a significant decrease only in patients with severe heart failure due to cardiomyopathy, but was not changed in those with valvular diseases. Storage and release of MIBG, calculated as the percentage myocardial MIBG washout from 15 min to 4 hours after isotope injection, was substantially accelerated in both patients with cardiomyopathy and valvular diseases in proportion to the severity of heart failure. These data suggest that, in severe heart failure associated with cardiomyopathy, norepinephrine uptake is reduced. Also, myocardial adrenergic nerve activity is accelerated in proportion to the severity of heart failure independent of the underlying cause. MIBG images were analyzed in 20 patients with mitral stenosis with the same methods to clarify whether myocardial adrenergic nerve activity is different in patients with heart failure without left ventricular volume or pressure overload. Myocardial uptake of MIBG did not show any significant difference. The percentage myocardial MIBG washout was increased in patients with severe heart failure. The closest correlation was between myocardial washout and cardiac output. In heart failure due to mitral stenosis, myocardial adrenergic nerve activity is intensified. Decrease in cardiac output associated with mitral stenosis acts as a potent stimulus for this intensification. (author)

[Myocardial perfusion imaging by digital subtraction angiography].

Science.gov (United States)

Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

1986-03-01

Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of the cardiac motion in myocardial infarction by the ECG-synchronized CT

International Nuclear Information System (INIS)

Watanabe, Shigeru; Shimizu, Masahiko; Yoshida, Hideo; Morooka, Nobuhiro; Shukuya, Masaki

1981-01-01

The cardiac motion in patients with myocardial infarction was analyzed by the ECG-synchronized computed tomography (CT). For ECG synchronization, the ECG gating method and the data sorting method were used. By the ECG gating method, the gated cardiac images during 0.1 msec intervals at end-diastolic and the end-systolic phases were obtained. By the data sorting method, phasic CT images were reconstructed retrospectively by selecting appropriate data from a series of consecutive scans taken with simultaneous continuous ECG recordings. Six normal subjects and eight patients with myocardial infarction were studied by the ECG gating method, and 14 normal subjects and 25 patients with myocardial infarction were studied by the data sorting method. The end-diastolic and the end-systolic pictures at mid left ventricular level were superimposed and the cardiac borders were traced for the analysis (Fig. 4). Then the cardiac cross-sectional areas at each cardiac phase (40 msec) were calculated, and a cardiac area curve was obtained by plotting them consecutively. The cross-sectional images were divided into right anterior, right posterior, left anterior and left posterior segments. Cardiac area curves of the each segment were also obtained for further analysis. From these curves, the changing ratio of cardiac areas (maximum area - minimum area/maximum area) and the maximum area velocity in systole and diastole were calculated. On the images and the cardiac area curves in myocardial infarction patients, abnormal myocardial movements such as partial akinesis, hypokinesis or paradoxical movement were apparent asd the area of abnormal motions corresponded well with the location of infarction determined by ECG, RI scanning and angiography. A decrease of the changing ratio and the velocity in the infarction area were shown (Fig. 6, 7) and the functional disturbances were suggested during not only systole but diastole also. (author)

Myocardial Hemorrhage After Acute Reperfused ST-Segment–Elevation Myocardial Infarction

Science.gov (United States)

Carrick, David; Haig, Caroline; Ahmed, Nadeem; McEntegart, Margaret; Petrie, Mark C.; Eteiba, Hany; Hood, Stuart; Watkins, Stuart; Lindsay, M. Mitchell; Davie, Andrew; Mahrous, Ahmed; Mordi, Ify; Rauhalammi, Samuli; Sattar, Naveed; Welsh, Paul; Radjenovic, Aleksandra; Ford, Ian; Oldroyd, Keith G.

2016-01-01

Background— The success of coronary reperfusion therapy in ST-segment–elevation myocardial infarction (MI) is commonly limited by failure to restore microvascular perfusion. Methods and Results— We performed a prospective cohort study in patients with reperfused ST-segment–elevation MI who underwent cardiac magnetic resonance 2 days (n=286) and 6 months (n=228) post MI. A serial imaging time-course study was also performed (n=30 participants; 4 cardiac magnetic resonance scans): 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. Myocardial hemorrhage was taken to represent a hypointense infarct core with a T2* value of hemorrhage 2 days post MI was associated with clinical characteristics indicative of MI severity and inflammation. Myocardial hemorrhage was a multivariable associate of adverse remodeling (odds ratio [95% confidence interval]: 2.64 [1.07–6.49]; P=0.035). Ten (4%) patients had a cardiovascular cause of death or experienced a heart failure event post discharge, and myocardial hemorrhage, but not microvascular obstruction, was associated with this composite adverse outcome (hazard ratio, 5.89; 95% confidence interval, 1.25–27.74; P=0.025), including after adjustment for baseline left ventricular end-diastolic volume. In the serial imaging time-course study, myocardial hemorrhage occurred in 7 (23%), 13 (43%), 11 (33%), and 4 (13%) patients 4 to 12 hours, 2 days, 10 days, and 7 months post reperfusion. The amount of hemorrhage (median [interquartile range], 7.0 [4.9–7.5]; % left ventricular mass) peaked on day 2 (Phemorrhage and microvascular obstruction follow distinct time courses post ST-segment–elevation MI. Myocardial hemorrhage was more closely associated with adverse outcomes than microvascular obstruction. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT02072850. PMID:26763281

Insulin stimulates the expression of the SHARP-1 gene via multiple signaling pathways.

Science.gov (United States)

Takagi, K; Asano, K; Haneishi, A; Ono, M; Komatsu, Y; Yamamoto, T; Tanaka, T; Ueno, H; Ogawa, W; Tomita, K; Noguchi, T; Yamada, K

2014-06-01

The rat enhancer of split- and hairy-related protein-1 (SHARP-1) is a basic helix-loop-helix transcription factor. An issue of whether SHARP-1 is an insulin-inducible transcription factor was examined. Insulin rapidly increased the level of SHARP-1 mRNA both in vivo and in vitro. Then, signaling pathways involved with the increase of SHARP-1 mRNA by insulin were determined in H4IIE rat hepatoma cells. Pretreatments with LY294002, wortmannin, and staurosporine completely blocked the induction effect, suggesting the involvement of both phosphoinositide 3-kinase (PI 3-K) and protein kinase C (PKC) pathways. In fact, overexpression of a dominant negative form of atypical protein kinase C lambda (aPKCλ) significantly decreased the induction of the SHARP-1 mRNA. In addition, inhibitors for the small GTPase Rac or Jun N-terminal kinase (JNK) also blocked the induction of SHARP-1 mRNA by insulin. Overexpression of a dominant negative form of Rac1 prevented the activation by insulin. Furthermore, actinomycin D and cycloheximide completely blocked the induction of SHARP-1 mRNA by insulin. Finally, when a SHARP-1 expression plasmid was transiently transfected with various reporter plasmids into H4IIE cells, the promoter activity of PEPCK reporter plasmid was specifically decreased. Thus, we conclude that insulin induces the SHARP-1 gene expression at the transcription level via a both PI 3-K/aPKCλ/JNK- and a PI 3-K/Rac/JNK-signaling pathway; protein synthesis is required for this induction; and that SHARP-1 is a potential repressor of the PEPCK gene expression. © Georg Thieme Verlag KG Stuttgart · New York.

ASSESSMENT OF THE MANAGEMENT OF SHARPS INJURIES IN GOVERNMENT HOSPITALS: THE MALAYSIAN SITUATION

Directory of Open Access Journals (Sweden)

M. Siti Haniza M.D PhD

2012-11-01

Full Text Available Introduction: Management of occupational hazards has been a priority and sharps injuries is a known potential risk to health care workers. With the known risks of potential infections, to the workers as well as the patients, our workers need protection from further danger. Objective: This study looked at the measures taken on managing the affected healthcare workers. Methods: A cross-sectional survey using self-administered questionnaire was sent to 55 hospital directors. They were required to inform on their management practices on sharps injuries. Results: The findings showed variations in the management of sharps injuries during and after office hours, variation in the site of keeping the records, person responsible and variation in the frequency of data analysis and presentation to hospital directors. Discussion: According to OSHA Act 1994, it is the responsibility of the employer to ensure safety, health and welfare of the employee. In management of sharps injury data from injury reporting should be compiled and assessed. Reporting feedback need to be encouraged with timely follow-up of all sharps injury cases. Reporting of sharps injuries is essential to ensure that all healthcare workers receive appropriate post-exposure medical treatment. Conclusion & Recommendation: A uniform management of sharps injuries protocol need to be established to improve reporting. An avenue to present sharps injuries data regularly is needed so as appropriate management of workers be ensured. Therefore adherence to the available guidelines need to be ensured. Key words: management, sharps injuries, healthcare workers

Seismic observation of a sharp post-garnet phase transition within the Farallon crust: Evidence for oceanic plateau subduction

Science.gov (United States)

Maguire, R.; Ritsema, J.

2017-12-01

The tectonic evolution of North America over the past 150 million years was heavily influenced by the complex subduction history of the Farallon plate. In particular, Laramide mountain building may have been triggered by the initiation of flat slab subduction in the late Cretaceous. While it has been proposed that the cause of slab flattening is related to the subduction of an oceanic plateau[1], direct geophysical evidence of a subducted oceanic plateau is lacking. Here, using P-to-S receiver functions, we detect a sharp seismic discontinuity at 720-km depth beneath the southeastern United States and Gulf of Mexico. We interpret this discontinuity as a garnet-to-bridgmanite phase transition occurring within a thickened Farallon crust. Our results are consistent with a subducted oceanic plateau (likely the conjugate half of the Hess rise) which is foundering below the base of the mantle transition zone. Additionally, we find a strong 520-km discontinuity beneath the southeastern United States which may indicate a hydrous transition zone due to the release of H2O from the Farallon slab. These results provide insight into the dynamics of flat slab subduction as well as the tectonic history of North America. [1] Livaccari, R. F., Burke, K., & Şengör, A. M. C. (1981). Was the Laramide orogeny related to subduction of an oceanic plateau? Nature, v. 289, p. 276-278, doi: 10.1038/289276a0

Mortality rate in type 2 myocardial infarction

DEFF Research Database (Denmark)

Saaby, Lotte; Poulsen, Tina Svenstrup; Diederichsen, Axel Cosmus Pyndt

2014-01-01

myocardial infarction, hypercholesterolemia, high p-creatinine, and diabetes mellitus. The multivariable-adjusted hazard ratio for type 2 myocardial infarction was 2.0 (95% confidence interval, 1.3-3.0). With shock as the only exception, mortality was independent of the triggering conditions leading to type....../119) in those with type 2 myocardial infarction and 26% (92/360) in those with type 1 myocardial infarction (P high age, prior myocardial infarction, type 2...... 2 myocardial infarction. CONCLUSIONS: Mortality in patients with type 2 myocardial infarction is high, reaching approximately 50% after 2 years. Further descriptive and survival studies are needed to improve the scientific evidence on which treatment of type 2 myocardial infarction is based....

Stability analysis of sharp-boundary Vlasov-fluid screw-pinch equilibria

International Nuclear Information System (INIS)

Lewis, H.R.; Turner, L.

1975-01-01

The Vlasov-fluid model is being used to study the linear stability of sharp-boundary screw pinches numerically. The numerical method appears to work well, and some preliminary results are reported. The sharp-boundary calculation is useful for gaining insight and for comparing with known MHD results. (auth)

VO(2peak), myocardial hypertrophy, and myocardial blood flow in endurance-trained men.

Science.gov (United States)

Laaksonen, Marko S; Heinonen, Ilkka; Luotolahti, Matti; Knuuti, Juhani; Kalliokoski, Kari K

2014-08-01

Endurance training induces cardiovascular and metabolic adaptations, leading to enhanced endurance capacity and exercise performance. Previous human studies have shown contradictory results in functional myocardial vascular adaptations to exercise training, and we hypothesized that this may be related to different degrees of hypertrophy in the trained heart. We studied the interrelationships between peak aerobic power (V˙O2peak), myocardial blood flow (MBF) at rest and during adenosine-induced vasodilation, and parameters of myocardial hypertrophy in endurance-trained (ET, n = 31) and untrained (n = 17) subjects. MBF and myocardial hypertrophy were studied using positron emission tomography and echocardiography, respectively. Both V˙O2peak (P negatively with adenosine-stimulated MBF, but when LV mass was taken into account as a partial correlate, this correlation disappeared. The present results show that increased LV mass in ET subjects explains the reduced hyperemic myocardial perfusion in this subject population and suggests that excessive LV hypertrophy has negative effect on cardiac blood flow capacity.

Stem cell mobilization induced by subcutaneous granulocyte-colony stimulating factor to improve cardiac regeneration after acute ST-elevation myocardial infarction: result of the double-blind, randomized, placebo-controlled stem cells in myocardial infarction (STEMMI) trial

DEFF Research Database (Denmark)

Ripa, RS; Jorgensen, E; Wang, Y

2006-01-01

BACKGROUND: Phase 1 clinical trials of granulocyte-colony stimulating factor (G-CSF) treatment after myocardial infarction have indicated that G-CSF treatment is safe and may improve left ventricular function. This randomized, double-blind, placebo-controlled trial aimed to assess the efficacy of......: Bone marrow stem cell mobilization with subcutaneous G-CSF is safe but did not lead to further improvement in ventricular function after acute myocardial infarction compared with the recovery observed in the placebo group...

13N-Ammonia pet-derived ventricular synchrony correlates with myocardial perfusion reserve better than left ventricular ejection fraction : A study in infarcted patients

NARCIS (Netherlands)

Juarez-Orozco, Luis Eduardo; Slart, Riemer; Tio, Rene A.; Inarra-Talboy, Fernando; Monroy, Andrea; Ayala-German, AnaGabriela; Dierckx, Rudi A.; Rosas, Erick Alexanderson

2016-01-01

Background: PET myocardial perfusion allows myocardial perfusion reserve (MPR) quantification as well as left ventricular ejection fraction (LVEF) and synchrony estimation through phase analysis. There is a relationship between MPR and LVEF and both have proven prognostic value in coronary artery

The sharp peak-flat trough pattern and critical speculation

OpenAIRE

Roehner, B. M.; Sornette, D.

1998-01-01

We find empirically a characteristic sharp peak-flat trough pattern in a large set of commodity prices. We argue that the sharp peak structure reflects an endogenous inter-market organization, and that peaks may be seen as local ``singularities'' resulting from imitation and herding. These findings impose a novel stringent constraint on the construction of models. Intermittent amplification is not sufficient and nonlinear effects seem necessary to account for the observations.

Surface-enhanced Raman scattering on periodic metal nanotips with tunable sharpness

International Nuclear Information System (INIS)

Linn, Nicholas C; Sun, C-H; Arya, Ajay; Jiang Peng; Jiang Bin

2009-01-01

This paper reports on a scalable bottom-up technology for producing periodic gold nanotips with tunable sharpness as surface-enhanced Raman scattering (SERS) substrates. Inverted silicon pyramidal pits, which are templated from non-close-packed colloidal crystals prepared by a spin-coating technology, are used as structural templates to replicate arrays of polymer nanopyramids with nanoscale sharp tips. The deposition of a thin layer of gold on the polymer nanopyramids leads to the formation of SERS-active substrates with a high enhancement factor (up to 10 8 ). The thickness of the deposited metal determines the sharpness of the nanotips and the resulting Raman enhancement factor. Finite-element electromagnetic modeling shows that the nanotips can significantly enhance the local electromagnetic field and the sharpness of nanotips greatly affects the SERS enhancement.

Analysis and protective measures of sharp instrument injury causes of sterilization and supply center

Directory of Open Access Journals (Sweden)

Hua YANG

2014-11-01

Full Text Available Objective: To analyze the causes of sharp injury in the sterilization and supply center, take protective measures, effectively avoid sharp instrument injury, and guarantee staff safety. Methods: Adopt a retrospective survey method, summarize sharp instrument injury data of sterilization and supply center in 2013, analyze the reasons of the occurrence of sharp instrument injury, and make protective countermeasures. Results: Sharp instrument injuries occurred mainly in the device classification, manual cleaning and device packaging process. Conclusion: Poor consciousness of occupational protection of the staff in the sterilization and supply center, nonstandard operation, and lack of training and supervision in place are the main reasons of occurrence of sharp instrument injury.

SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

Directory of Open Access Journals (Sweden)

N. Maghamipour N. Safaei

2007-06-01

Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

Myocardial perfusion imaging for detection of silent myocardial ischemia

International Nuclear Information System (INIS)

Beller, G.A.

1988-01-01

Despite the widespread use of the exercise stress test in diagnosing asymptomatic myocardial ischemia, exercise radionuclide imaging remains useful for detecting silent ischemia in numerous patient populations, including those who are totally asymptomatic, those who have chronic stable angina, those who have recovered from an episode of unstable angina or an uncomplicated myocardial infarction, and those who have undergone angioplasty or received thrombolytic therapy. Studies show that thallium scintigraphy is more sensitive than exercise electrocardiography in detecting ischemia, i.e., in part, because perfusion defects occur more frequently than ST depression and before angina in the ischemic cascade. Thallium-201 scintigraphy can be performed to differentiate a true- from a false-positive exercise electrocardiographic test in patients with exercise-induced ST depression and no angina. The development of technetium-labeled isonitriles may improve the accuracy of myocardial perfusion imaging. 11 references

Application of myocardial perfusion quantitative imaging for the evaluation of therapeutic effect in canine with myocardial infarction

International Nuclear Information System (INIS)

Liang Hong; Chen Ju; Liu Sheng; Zeng Shiquan

2000-01-01

Myocardial blood perfusion (MBP) ECT and quantitative analysis were performed in 10 canines with experimental acute myocardial infarct (AMI). The accuracy of main myocardial quantitative index, including defect volume (DV) and defect fraction (DF), was estimated and correlated with histochemical staining (HS) of infarcted area. Other 21/AMI canines were divided into Nd:YAG laser trans-myocardial revascularization treated group LTMR and control group. All canines were performed MBP ECT after experimental AMI. Results found that the infarcted volume (IV) measured by HS has well correlated (r 0.88) with DV estimated by myocardial quantitative analysis. But the DF values calculated by both methods was not significantly different (t = 1.28 P > 0.05). In LTMR group 27.5% +- 3.9%, the DF is smaller than control group 32.1% +- 4.6% (t = 2.49 P 99m Tc-MIBI myocardial perfusion SPECT and quantitative study can accurately predict the myocardial blood flow and magnitude of injured myocardium. Nd:YAG LTMR could improve myocardial blood perfusion of ischemic myocardium and decrease effectively the infarct areas

Objective assessment of knife sharpness over a working day cutting meat.

Science.gov (United States)

Savescu, Adriana; Cuny-Guerrier, Aude; Wild, Pascal; Reno, Gilles; Aublet-Cuvelier, Agnès; Claudon, Laurent

2018-04-01

Knife sharpness is one of multiple factors involved in musculoskeletal disorders in industrial meat cutting. The aim of this study was to objectively evaluate, in real working situations, how knife sharpness changed over a working day cutting meat, and to analyse the impact of sharpening, steeling and meat-cutting activities on these variations. Twenty-two meat-cutting workers from three different companies participated in the study. The methods included measurements of knife sharpness in relation to real work situations and consideration of the way meat-cutting and sharpening operations were organised. Results showed that the type of meat-cutting activities, the steeling strategy adopted by the worker, including the types of tool used, and the overall organisation of the sharpening task all had a significant influence on how knife sharpness evolved over a 2-h period and over an entire working day. To improve MSD prevention, sharpening and steeling operations should not be considered as independent activities, but taken into account as a continuity of working actions. Appropriate assessment of knife sharpness by meat cutters affects how they organise meat-cutting and sharpening tasks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Left anterior descending coronary artery myocardial bridging by multislice computed tomography: Correlation with clinical findings

Energy Technology Data Exchange (ETDEWEB)

Jodocy, Daniel; Aglan, Iman [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Friedrich, Guy [Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Mallouhi, Ammar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Pachinger, Otmar [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Clinical Department of Cardiology, Innsbruck Medical University, Innsbruck (Austria); Jaschke, Werner [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria); Feuchtner, Gudrun M. [Clinical Department of Radiology II, Innsbruck Medical University, Innsbruck (Austria)], E-mail: gudrun.feuchtner@i-med.ac.at

2010-01-15

Objective: To assess the relationship between left anterior descending (LAD) coronary artery myocardial bridging detected by 64-slice computed tomography (CT) and clinical findings. Methods: 221 consecutive patients were examined with coronary 64-slice CT angiography. 21 patients with coronary stenosis >50% were excluded. The length, depth, and luminal narrowing of LAD myocardial bridges during systole and diastole were measured. CT findings were compared with the treadmill ECG-stress test, and clinical symptoms. Results: Myocardial bridges of the LAD were found in 23% of patients (51/221) (length, 14.9 {+-} 6.5 mm; depth, 2.6 {+-} 1.6 mm). A significant difference was noted between the LAD luminal diameter before the intramyocardial course and intramyocardially, for both diastole and systole (p < 0.001); with a higher diameter reduction of 27% for end-systole compared to end-diastole with 15% (p = 0.006). Systolic LAD intramyocardial luminal narrowing >50% was found in 3/25 (8%). 30/51 (59%) of bridges were 'deep' (>2 mm myocardial depth), 21/51 (41%) were 'superficial'. The prevalence of a positive ECG-stress tests for the anterior myocardial region was significantly higher in patients with LAD myocardial bridges (34/50; 68%) compared to those without (28/144; 19.4%) (p < 0.001). There was no difference between 'superficial' and 'deep' LAD myocardial bridges in regard to a positive treadmill ECG-stress test. Typical angina was rare with 6%. Conclusion: LAD myocardial bridges are common findings and can possibly explain a positive exercise ECG-stress test for anterior myocardial ischemia. Intramyocardial LAD segments show mild-to-moderate luminal narrowing at rest, which is higher during end-systolic phase.

Sharp Dissection versus Electrocautery for Radial Artery Harvesting

Science.gov (United States)

Marzban, Mehrab; Arya, Reza; Mandegar, Mohammad Hossein; Karimi, Abbas Ali; Abbasi, Kiomars; Movahed, Namvar; Abbasi, Seyed Hesameddin

2006-01-01

Radial arteries have been increasingly used during the last decade as conduits for coronary artery revascularization. Although various harvesting techniques have been described, there has been little comparative study of arterial damage and patency. A radial artery graft was used in 44 consecutive patients, who were randomly divided into 2 groups. In the 1st group, the radial artery was harvested by sharp dissection and in the 2nd, by electrocautery. These groups were compared with regard to radial artery free flow, harvest time, number of clips used, complications, and endothelial damage. Radial artery free flow before and after intraluminal administration of papaverine was significantly greater in the electrocautery group (84.3 ± 50.7 mL/min and 109.7 ± 68.5 mL/min) than in the sharp-dissection group (52.9 ± 18.3 mL/min and 69.6 ± 28.2 mL/ min) (P =0.003). Harvesting time by electrocautery was significantly shorter (25.4 ± 4.3 min vs 34.4 ± 5.9 min) (P =0.0001). Electrocautery consumed an average of 9.76 clips, versus 22.45 clips consumed by sharp dissection. The 2 groups were not different regarding postoperative complications, except for 3 cases of temporary paresthesia of the thumb in the electrocautery group; histopathologic examination found no endothelial damage. We conclude that radial artery harvesting by electrocautery is faster and more economical than harvesting by sharp dissection and is associated with better intraoperative flow and good preservation of endothelial integrity. PMID:16572861

[Hypertrophic cardiomyopathy showing no 123I-BMIPP myocardial accumulation with type I CD36 deficiency].

Science.gov (United States)

Watanabe, K; Miyajima, S; Kusano, Y; Tanabe, N; Hirokawa, Y

1997-07-01

A 57 years old male consulted our hospital in complaining chest oppression and short of breath. Familial and dilated phase hypertrophic cardiomyopathy (HCM) was detected by ECG, echocardiography, left ventriculography and left ventricular endomyocardial biopsy. 201T1 SPECT showed regional increased accumulation in the ventricular septum, however, no myocardial accumulation of 123I-beta-methyl-p-iodophenylpentadecanoic acid (123I-BMIPP) was observed. We analyzed CD36 in this patient, and found he had type 1 CD36 deficiency. Myocardial uptake of long-chain fatty acids occurs via a specific transporter, which is homologous with human CD36. We hypothesize that CD36 deficiency, especially type 1 CD36 deficiency, might be one factor of no myocardial 123I-BMIPP uptake.

Exercise and rest Tl-201 myocardial SPECT, and low dose dobutamine echocardiography to assess myocardial viability in patients with myocardial infarction

International Nuclear Information System (INIS)

Toyama, Takuji; Ishida, Yoshio; Shimonagata, Tsuyoshi; Kawano, Shigeo; Beppu, Shintaro; Nishimura, Tsunehiko.

1994-01-01

To evaluate viability of infarcted myocardium, findings of Tl-201 myocardial SPECT were compared with those of low-dose dobutamine (DOB) echocardiography. The subjects were 19 patients with myocardial infarction (23 infarcted zones), consisting of 16 men and 3 women. Findings on myocardial SPECT were classified as evidence of myocardial viability (14 zones, Group A) and no evidence of myocardial viability (9 zones, Group B). For both groups, wall motion and regional % uptake (%UP) were obtained. DOB echocardiography revealed an improvement in 5 of 8 akinesis zones in Group A. In addition, one other zone was found improved by follow-up examination. Six hypokinesis zones were all found improved on DOB echocardiography. Out of a total of 14 akinesis or hypokinesis zones, 11 (79%) showed improvement on DOB echocardiography in Group A. In Group B, all akinesis zones remained unchanged on DOB echocardiography, although one zone was improved by follow-up examination. In 11 zones in which wall motion was improved on DOB echocardiography, %UT was increased by an average of 58% on 4 hr-delayed images and 70% on resting images. The corresponding figures for 12 zones which did not improve on DOB echocardiography were 49% and 50% on the average, respectively. In conclusion, low-dose DOB echocardiography appeared to reflect viability of severely infarcted myocardium, although it had a slightly lower sensitivity than convensional Tl-201 myocardial SPECT in its ability to detect. (N.K.)

Myocardial contusion following nonfatal blunt chest trauma

International Nuclear Information System (INIS)

Kumar, S.A.; Puri, V.K.; Mittal, V.K.; Cortez, J.

1983-01-01

Currently available diagnostic techniques for myocardial contusion following blunt chest trauma were evaluated. We investigated 30 patients prospectively over a period of 1 year for the presence of myocardial contusion. Among the 30 patients, eight were found to have myocardial contusion on the basis of abnormal electrocardiograms, elevated creatine phosphokinase MB fraction (CPK-MB), and positive myocardial scan. Myocardial scan was positive in seven of eight patients (87.5%). CPK-MB fraction was elevated in four of eight patients (50%). Definitive electrocardiographic changes were seen in only two of eight patients (25%). It appears that myocardial scan using technetium pyrophosphate and CPK-MB fraction determinations are the most reliable aids in diagnosis of myocardial contusion following blunt chest trauma

Hypertension impairs myocardial blood perfusion reserve in subjects without regional myocardial ischemia

International Nuclear Information System (INIS)

Nakajima, Hiroshi; Onishi, Katsuya; Kurita, Tairo

2010-01-01

Quantitative analysis of myocardial perfusion MRI can provide noninvasive assessments of myocardial perfusion reserve (MPR), which is associated with endothelial function. Endothelial function is influenced by various factors, including hypertension, diabetes, dyslipidemia, renal dysfunction and anemia. The purpose of this study was to evaluate which risk factor is the strongest effector of MPR in subjects without regional myocardial ischemia. We studied 110 patients (66 years ±10, male 68%, hypertension 76%, diabetes mellitus (DM) 40% and dyslipidemia 65%) without regional myocardial ischemia. Adenosine triphosphate (ATP) stress and rest first-pass perfusion magnetic resonance (MR) images were acquired with a 1.5-T MR system, and MPR was calculated as the ratio of stress to rest myocardial blood flow (MBF). Average rest MBF in 110 patients was 1.07±0.62 ml min -1 g -1 , whereas stress MBF was 3.15±1.93 ml min -1 g -1 and the MPR was 3.33±1.82. Rest MBF correlated significantly with hematocrit, whereas stress MBF showed a strong correlation with estimated glomerular filtration rate (e-GFR). MPR was associated with hypertension, age, e-GFR, hematocrit and left ventricular mass index (LVMI). In multiple regression analysis, hypertension (P=0.003, β=-0.274) showed the strongest correlation with MPR among other risk factors, such as diabetes (P=ns), dyslipidemia (P=ns), e-GFR (P=ns), LVMI (P=0.007, β=-0.248) and hematocrit (P=ns) after adjusting age and gender. Hypertension is the most important effector of MPR in subjects without myocardial ischemia. (author)

Hypertension impairs myocardial blood perfusion reserve in subjects without regional myocardial ischemia

Energy Technology Data Exchange (ETDEWEB)

Nakajima, Hiroshi; Onishi, Katsuya; Kurita, Tairo [Mie Univ., Graduate School of Medicine, Tsu, Mie (Japan)

2010-11-15

Quantitative analysis of myocardial perfusion MRI can provide noninvasive assessments of myocardial perfusion reserve (MPR), which is associated with endothelial function. Endothelial function is influenced by various factors, including hypertension, diabetes, dyslipidemia, renal dysfunction and anemia. The purpose of this study was to evaluate which risk factor is the strongest effector of MPR in subjects without regional myocardial ischemia. We studied 110 patients (66 years {+-}10, male 68%, hypertension 76%, diabetes mellitus (DM) 40% and dyslipidemia 65%) without regional myocardial ischemia. Adenosine triphosphate (ATP) stress and rest first-pass perfusion magnetic resonance (MR) images were acquired with a 1.5-T MR system, and MPR was calculated as the ratio of stress to rest myocardial blood flow (MBF). Average rest MBF in 110 patients was 1.07{+-}0.62 ml min{sup -1} g{sup -1}, whereas stress MBF was 3.15{+-}1.93 ml min{sup -1} g{sup -1} and the MPR was 3.33{+-}1.82. Rest MBF correlated significantly with hematocrit, whereas stress MBF showed a strong correlation with estimated glomerular filtration rate (e-GFR). MPR was associated with hypertension, age, e-GFR, hematocrit and left ventricular mass index (LVMI). In multiple regression analysis, hypertension (P=0.003, {beta}=-0.274) showed the strongest correlation with MPR among other risk factors, such as diabetes (P=ns), dyslipidemia (P=ns), e-GFR (P=ns), LVMI (P=0.007, {beta}=-0.248) and hematocrit (P=ns) after adjusting age and gender. Hypertension is the most important effector of MPR in subjects without myocardial ischemia. (author)

Localness of energy cascade in hydrodynamic turbulence, II. Sharp spectral filter

Energy Technology Data Exchange (ETDEWEB)

Aluie, Hussein [Los Alamos National Laboratory; Eyink, Gregory L [JOHNS HOPKINS UNIV.

2009-01-01

We investigate the scale-locality of subgrid-scale (SGS) energy flux and interband energy transfers defined by the sharp spectral filter. We show by rigorous bounds, physical arguments, and numerical simulations that the spectral SGS flux is dominated by local triadic interactions in an extended turbulent inertial range. Interband energy transfers are also shown to be dominated by local triads if the spectral bands have constant width on a logarithmic scale. We disprove in particular an alternative picture of 'local transfer by nonlocal triads,' with the advecting wavenumber mode at the energy peak. Although such triads have the largest transfer rates of all individual wavenumber triads, we show rigorously that, due to their restricted number, they make an asymptotically negligible contribution to energy flux and log-banded energy transfers at high wavenumbers in the inertial range. We show that it is only the aggregate effect of a geometrically increasing number of local wavenumber triads which can sustain an energy cascade to small scales. Furthermore, nonlocal triads are argued to contribute even less to the space-average energy flux than is implied by our rigorous bounds, because of additional cancellations from scale-decorrelation effects. We can thus recover the -4/3 scaling of nonlocal contributions to spectral energy flux predicted by Kraichnan's abridged Lagrangian-history direct-interaction approximation and test-field model closures. We support our results with numerical data from a 512{sup 3} pseudospectral simulation of isotropic turbulence with phase-shift dealiasing. We also discuss a rigorous counterexample of Eyink [Physica D 78, 222 (1994)], which showed that nonlocal wavenumber triads may dominate in the sharp spectral flux (but not in the SGS energy flux for graded filters). We show that this mathematical counter example fails to satisfy reasonable physical requirements for a turbulent velocity field, which are employed in our

Evaluation of myocardial abnormalities in collagen diseases by thallium-201 myocardial scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Yamano, Shigeru; Kagoshima, Tadashi; Sugihara, Kiyotaka (Nara Medical Univ., Kashihara (Japan)) (and others)

1993-12-01

This study was performed to evaluate myocardial abnormalities in patients with collagen diseases by exercise and rest thallium-201 myocardial scintigrams. A total of 65 patients without ischemic ECG changes, consisting of 18 with systemic lupus erythematosus (SLE), 18 with polymyositis (PM), 8 with progressive systemic sclerosis (PSS), and 21 with Sjoegren's syndrome (SjS), was enrolled in this study. Reversible exercise-induced defects scintigraphically suggesting myocardial ischemia were noted in 8 cases of SLE, 4 cases of PM, 4 cases of PSS, and 3 cases of SjS. Nineteen patients had exercise-induced defects and underwent cardiac catheterization, 8 of whom had normal coronary angiograms. Fixed hypoperfusion areas were observed in one case of SLE, 6 cases of PM and 3 cases of SjS. Rest thallium-201 myocardial scintigram disclosed hypoperfusion areas which were not induced by exercise in 2 cases of SLE, 3 cases of PM, one case of PSS and 5 cases of SjS. Echocardiogram showed no significant differences in ejection fraction and % fractional shortening between the disease groups and healthy control group. These findings suggest that patients with collagen diseases have abnormalities of coronary circulation at the level of the intramural vasculature before cardiac function impairment, myocardial fibrosis and functional abnormalities at the cell membrane. (author).

Software design of SHARP

International Nuclear Information System (INIS)

Siegel, A.; Tautges, T.; Caceres, A.; Kaushik, D.; Fischer, P.; Palmiotti, G.; Smith, M.; Ragusa, J.

2007-01-01

SHARP (Simulation-based High-efficiency Advanced Reactor Prototyping) is a modern suite of codes to simulate the key components of a fast reactor core. The SHARP tool-kit is organized as a collection of modules, each representing the key components of the physics to be modeled - neutron transport, thermal hydraulics, fuel/structure behavior - together with pre and post-processing for geometry definition, mesh generation, visualization, user interface, etc. The physics models are designed to make minimal possible use of lumped parameter models, homogenization, and empirical correlations in favor of more direct solution of the fundamental governing equations, when sufficient computing resources are available. Thus, one of the key design goals is to effectively leverage leadership class computing resources - viz. BG/P and Cray Supercomputers that are on the current trajectory to delivering sustained peta-flops performance. Further, the nature of the physical problem to be investigated will require either strong or weak coupling between some or all of the existing modules (e.g. operator split vs. fully coupled), while multiple implementations of each physics module, representing different algorithms, will also be required (e.g. deterministic versus Monte Carlo) for verification and to explore different physical regimes. Accomplishing these goals in the context of ultra-scalable architectures and multidisciplinary and possibly distributed development teams is a daunting task. In this paper we explain our initial lightweight and loosely coupled framework, its initial design, and a number of current open research questions in this area. (authors)

Comparison of blood biochemics between acute myocardial infarction models with blood stasis and simple acute myocardial infarction models in rats

International Nuclear Information System (INIS)

Qu Shaochun; Yu Xiaofeng; Wang Jia; Zhou Jinying; Xie Haolin; Sui Dayun

2010-01-01

Objective: To construct the acute myocardial infarction models in rats with blood stasis and study the difference on blood biochemics between the acute myocardial infarction models with blood stasis and the simple acute myocardial infarction models. Methods: Wistar rats were randomly divided into control group, acute blood stasis model group, acute myocardial infarction sham operation group, acute myocardial infarction model group and of acute myocardial infarction model with blood stasis group. The acute myocardial infarction models under the status of the acute blood stasis in rats were set up. The serum malondialdehyde (MDA), nitric oxide (NO), free fatty acid (FFA), tumor necrosis factor-α (TNF-α) levels were detected, the activities of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the levels of prostacycline (PGI2), thromboxane A 2 (TXA 2 ) and endothelin (ET) in plasma were determined. Results: There were not obvious differences in MDA, SOD, GSH-Px and FFA between the acute myocardial infarction models with blood stasis in rats and the simple acute myocardial infarction models (P 2 and NO, and the increase extents of TXA 2 , ET and TNF-α in the acute myocardial infarction models in rats with blood stasis were higher than those in the simple acute myocardial infarction models (P 2 and NO, are significant when the acute myocardial infarction models in rats with blood stasis and the simple acute myocardial infarction models are compared. The results show that it is defective to evaluate pharmacodynamics of traditional Chinese drug with only simple acute myocardial infarction models. (authors)

Quantitative myocardial blood flow with Rubidium-82 PET

DEFF Research Database (Denmark)

Hagemann, Christoffer E; Ghotbi, Adam A; Kjær, Andreas

2015-01-01

Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1) identificat......Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1...... global MFR and major adverse cardiovascular events (MACE), and together with new diagnostic possibilities from measuring the longitudinal myocardial perfusion gradient, cardiac (82)Rb PET faces a promising clinical future. This article reviews current evidence on quantitative (82)Rb PET's ability...

SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

Science.gov (United States)

Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

2016-01-01

Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions.

Sharp vorticity gradients in two-dimensional turbulence and the energy spectrum

DEFF Research Database (Denmark)

Kuznetsov, E.A.; Naulin, Volker; Nielsen, Anders Henry

2010-01-01

Formation of sharp vorticity gradients in two-dimensional (2D) hydrodynamic turbulence and their influence on the turbulent spectra are considered. The analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together with the di-vorticity lines...... is developed and compressibility of this mapping appears as the main reason for the formation of the sharp vorticity gradients at high Reynolds numbers. In the case of strong anisotropy the sharp vorticity gradients can generate spectra which fall off as k −3 at large k, which appear to take the same form...

Myocardial scintigraphy: methods and indications

International Nuclear Information System (INIS)

Knapp, W.H.

1993-01-01

Myocardial scintigraphy comprises perfusion imaging using TI-201 or - more recently - Tc-99m-labeled compounds with high affinity to myocytes. Imaging with these agents has become an important procedure in the detection of coronary artery disease, particularly in patients with non-diagnostic stress-ECG, in the functional evaluation of coronary stenoses after angiographical documentation in order to meet the adequate therapy decision, in therapy monitoring and follow-up, in the post infarction assessment of myocardial viability and differentiation between severe ischemia and scar and, occasionally, in acute ischemia. The use of positron emitters does not offer significant advantages for mere perfusion imaging, but is indispensable for the scintigraphic investigation of certain aspects of myocardial metabolism, particularly for the differentiation of viable ischemic wall segments from irreversibly damaged tissue. Imaging of myocardial necrosis has been improved by the introduction of labeled antimyosin antibody fragments and offers a considerable clinical potential in the diagnosis of myocarditis and cardiac transplant rejection. Neurohumoral aspects are increasingly involved in our understanding of myocardial failure. Scintigraphy of innervation/neurotransmission contributes to the investigation of pathophysiological alterations in myocardial insufficiency and in heart transplants. (orig.) [de

Theoretical considerations in measurement of time discrepancies between input and myocardial time-signal intensity curves in estimates of regional myocardial perfusion with first-pass contrast-enhanced MRI.

Science.gov (United States)

Natsume, Takahiro; Ishida, Masaki; Kitagawa, Kakuya; Nagata, Motonori; Sakuma, Hajime; Ichihara, Takashi

2015-11-01

The purpose of this study was to develop a method to determine time discrepancies between input and myocardial time-signal intensity (TSI) curves for accurate estimation of myocardial perfusion with first-pass contrast-enhanced MRI. Estimation of myocardial perfusion with contrast-enhanced MRI using kinetic models requires faithful recording of contrast content in the blood and myocardium. Typically, the arterial input function (AIF) is obtained by setting a region of interest in the left ventricular cavity. However, there is a small delay between the AIF and the myocardial curves, and such time discrepancies can lead to errors in flow estimation using Patlak plot analysis. In this study, the time discrepancies between the arterial TSI curve and the myocardial tissue TSI curve were estimated based on the compartment model. In the early phase after the arrival of the contrast agent in the myocardium, the relationship between rate constant K1 and the concentrations of Gd-DTPA contrast agent in the myocardium and arterial blood (LV blood) can be described by the equation K1={dCmyo(tpeak)/dt}/Ca(tpeak), where Cmyo(t) and Ca(t) are the relative concentrations of Gd-DTPA contrast agent in the myocardium and in the LV blood, respectively, and tpeak is the time corresponding to the peak of Ca(t). In the ideal case, the time corresponding to the maximum upslope of Cmyo(t), tmax, is equal to tpeak. In practice, however, there is a small difference in the arrival times of the contrast agent into the LV and into the myocardium. This difference was estimated to correspond to the difference between tpeak and tmax. The magnitudes of such time discrepancies and the effectiveness of the correction for these time discrepancies were measured in 18 subjects who underwent myocardial perfusion MRI under rest and stress conditions. The effects of the time discrepancies could be corrected effectively in the myocardial perfusion estimates. Copyright © 2015 Elsevier Inc. All rights

SHARP: A multi-mission AI system for spacecraft telemetry monitoring and diagnosis

Science.gov (United States)

Lawson, Denise L.; James, Mark L.

1989-01-01

The Spacecraft Health Automated Reasoning Prototype (SHARP) is a system designed to demonstrate automated health and status analysis for multi-mission spacecraft and ground data systems operations. Telecommunications link analysis of the Voyager II spacecraft is the initial focus for the SHARP system demonstration which will occur during Voyager's encounter with the planet Neptune in August, 1989, in parallel with real-time Voyager operations. The SHARP system combines conventional computer science methodologies with artificial intelligence techniques to produce an effective method for detecting and analyzing potential spacecraft and ground systems problems. The system performs real-time analysis of spacecraft and other related telemetry, and is also capable of examining data in historical context. A brief introduction is given to the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory. The current method of operation for monitoring the Voyager Telecommunications subsystem is described, and the difficulties associated with the existing technology are highlighted. The approach taken in the SHARP system to overcome the current limitations is also described, as well as both the conventional and artificial intelligence solutions developed in SHARP.

Proliferation of sharp kinks on cosmic (super)string loops with junctions

International Nuclear Information System (INIS)

Binetruy, P.; Bohe, A.; Hertog, T.; Steer, D. A.

2010-01-01

Motivated by their effect on the gravitational wave signal emitted by cosmic strings, we study the dynamics of kinks on strings of different tensions meeting at junctions. The propagation of a kink through a Y junction leads to the formation of three 'daughter' kinks. Assuming a uniform distribution of the incoming wave vectors at the junction, we find there is a significant region of configuration space in which the sharpness of at least one of the daughter kinks is enhanced relative to the sharpness of the initial kink. For closed loops with junctions we show this leads to an exponential growth in time of very sharp kinks. Using numerical simulations of realistic, evolving cosmic string loops with junctions to calculate the distribution of kink amplitudes as a function of time, we show that loops of this kind typically develop several orders of magnitude of very sharp kinks before the two junctions collide. This collision, or other effects such as gravitational backreaction, may end the proliferation.

Anticoagulants for secondary prevention after acute myocardial infarction: lessons from the past decade

NARCIS (Netherlands)

Atar, D.; Bode, C.; Stuerzenbecher, A.; Verheugt, F.W.A.

2014-01-01

The impact of an acute coronary syndrome (ACS) event, such as an acute myocardial infarction (MI), is not limited to the acute management phase; patients face an elevated risk of residual atherothrombotic events that commonly requires chronic management for months or even years. Significant advances

Evaluation of myocardial involvement in Duchenne's progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

International Nuclear Information System (INIS)

Kawai, Naoki; Sotobata, Iwao; Okada, Mitsuhiro

1985-01-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. A qualitative analysis was performed from five projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in the LV posterolateral or posterior wall (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle involvements or thoracic deformities assessed by transmission computed tomography. Extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. Progression of the myocardial scintigraphic abnormalities were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies over 2 to 3 years. It was concluded that thallium myocardial perfusion imaging is a useful clinical technique to assess myocardial involvement in Duchenne's progressive muscular dystrophy. (author)

Assessment of myocardial washout of Tc-99m-sestamibi in patients with chronic heart failure. Comparison with normal control

Energy Technology Data Exchange (ETDEWEB)

Kumita, Shin-ichiro; Seino, Yoshihiko; Cho, Keiichi; Nakajo, Hidenobu; Toba, Masahiro; Fukushima, Yoshimitsu; Takano, Teruo; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan); Okamoto, Noriake [Bristol-Myers Squibb K.K., Tokyo (Japan)

2002-06-01

In contrast to {sup 201}TlCl, {sup 99m}Tc-sestamibi shows very slow myocardial clearance after its initial myocardial uptake. In the present study, myocardial washout of {sup 99m}Tc-sestamibi was calculated in patients with non-ischemic chronic heart failure (CHF) and compared with biventricular parameters obtained from first-pass and ECG-gated myocardial perfusion SPECT data. After administration of {sup 99m}Tc-sestamibi, 25 patients with CHF and 8 normal controls (NC) were examined by ECG-gated myocardial perfusion SPECT and planar data acquisition in the early and delayed (interval of 3 hours) phase. Left ventricular ejection fraction (LVEF, %), peak filling rate (PFR, sec{sup -1}), end-diastolic volume (LVEDV, ml) and end-systolic volume (LVESV, ml) were automatically calculated from the ECG-gated SPECT data. Myocardial washout rates over 3 hours were calculated from the early and delayed planar images. Myocardial washout rates in the CHF group (39.6{+-}5.2%) were significantly higher than those in the NC group (31.2{+-}5.5%, p<0.01). The myocardial washout rates for the 33 subjects showed significant correlations with LVEF (r=-0.61, p<0.001), PFR (r=-0.47, p<0.01), LVEDV (r=0.45, p<0.01) and LVESV (r=0.48, p<0.01). The myocardial washout rate of {sup 99m}Tc-sestamibi is considered to be a novel marker for the diagnosis of myocardial damage in patients with chronic heart failure. (author)

Histochemical and immunohistochemical analyses of the myocardial scar fallowing acute myocardial infarction

Directory of Open Access Journals (Sweden)

Tatić Vujadin

2012-01-01

Full Text Available Background/Aim. The heart has traditionally been considered as a static organ without capacity of regeneration after trauma. Currently, the more and more often asked question is whether the heart has any intrinsic capacities to regenerate myocytes after myocardial infarction. The aim of this study was to present the existence of the preserved muscle fibers in the myocardial scar following myocardial infarction as well as the presence of numerous cells of various size and form that differently reacted to the used immunohistochemical antibodies. Methods. Histological, histochemical and immunohistochemical analyses of myocardial sections taken from 177 patients who had died of acute myocardial infarction and had the myocardial scar following myocardial infarction, were carried out. More sections taken both from the site of acute infarction and scar were examined by the following methods: hematoxylin-eosin (HE, periodic acid schiff (PAS, PAS-diastasis, Masson trichrom, Malory, van Gieson, vimentin, desmin, myosin, myoglobin, alpha actin, smoth muscle actin (SMA, p53, leukocyte common antigen (LCA, proliferating cell nuclear antigen (PCNA, Ki-67, actin HHF35, CD34, CD31, CD45, CD45Ro, CD8, CD20. Results. In all sections taken from the scar region, larger or smaller islets of the preserved muscle fibers with the signs of hypertrophy were found. In the scar, a large number of cells of various size and form: spindle, oval, elongated with abundant cytoplasm, small with one nucleus and cells with scanty cytoplasm, were found. The present cells differently reacted to histochemical and immunohistochemical methods. Large oval cells showed negative reaction to lymphocytic and leukocytic markers, and positive to alpha actin, actin HHF35, Ki-67, myosin, myoglobin and desmin. Elongated cells were also positive to those markers. Small mononuclear cells showed positive reaction to lymphocytic markers. Endothelial and smooth muscle cells in the blood vessel walls

Fatty acid myocardial imaging using 123I-β-methyl-iophenyl pentadecanoic acid (BMIPP): Comparison of myocardial perfusion and fatty acid utilization in canine myocardial infarction

International Nuclear Information System (INIS)

Nishimura, Tsunehiko; Sago, Masayoshi; Kihara, Koichi; Oka, Hisashi; Shimonagata, Tsuyoshi; Katabuchi, Tetsuro; Hayashi, Makoto; Uehara, Toshiisa; Hayashida, Kohei; Noda, Hiroyuki; Takano, Hisateru

1989-01-01

To evaluate the relationship between myocardial perfusion and fatty acid metabolism in canine myocardial infarction, 16 dogs were studied using thallium and 123 I-β-methyl-iodophenyl pentadecanoic acid (BMIPP). Eight dogs (group A) had left anterior coronary arterial occlusion (6 h ligation), 6 dogs (group B) had reperfusion (3 h ligation and 1 h reperfusion) and 2 dogs served as the normal control. Myocardial imaging with BMIPP was excellent, owing to its higher uptake and longer retention in myocardium and rapid blood disappearance in addition to diminished liver and lung uptake. The mean half time value which was generated from the BMIPP myocardial washout curve, was significantly larger in the reperfused myocardium. The gamma camera imaging showed uncoupling of BMIPP and thallium (BMIPP uptake greater than thallium uptake) in five dogs in group B. On the other hand, all dogs in group A had a persistent defect in BMIPP and thallium uptake. Our findings indicate that the combination of BMIPP and thallium for myocardial imaging supply different information about the zone of infarction and ischemia, which may be useful for the assessment of myocardial viability. (orig.)

Quantitative assessment of myocardial blood flow by measurement of fractional myocardial uptake of 201Tl

International Nuclear Information System (INIS)

Yonekura, Yoshiharu; Ishii, Yasushi; Torizuka, Kanji; Kadota, Kazunori; Kambara, Hirofumi

1980-01-01

Fractional Myocardial uptake of 201 Tl was measured for the quantitative assessment of myocardial blood flow in coronary artery disease (CAD). 10 normals and 28 CAD, 7 of which have less than 50% stenosis (CAD I) and 21 of which have more than 50% stenosis (CAD II) in the proximal portion of coronary arteries, were studied at rest and with submaximal exercise loading by bicycle ergometer. After intravenous injection of 201 Tl, its rapid transport process was recorded during the initial 5 minutes by a scintillation camera and a minicomputer. Total injected dosage (T) was obtained from the counts of the entire chest region during the initial passage of the tracer through the heart and lung. Myocardial uptake (M) was counted with the same geometry from the subsequent accumulation within the myocardial region with subtraction of the background activities in the upper mediastinal region (B). The fractional myocardial uptake of 201 Tl ((M-B)/T) is assumed to be proportional to the fractional myocardial blood flow to cardiac output (MBF/CO) according to the indicator fractionation principle. The average value of MBF/CO at rest in CAD (4.11 +- 1.12%) was significantly greater than in normals (3.36 +- 0.49%), which may be caused by an increased left ventricular mass in CAD. Change rate of MBF/CO on the exercise loading was significantly less in CAD I (1.36 +- 0.14) and in CAD II (1.11 +- 0.21) than in normals (1.75 +- 0.11). MBF/CO increased proportionally to the increment of the double product of heart rate and systolic blood pressure by exercise loading in normals, whereas it didn't in CAD. The sensitivity of this method was superior to the stress electrocardiogram and the stress myocardial perfusion imaging, not only in CAD II but also in CAD I. This result indicated that this type of global assessment of the myocardial reserve capacity is valuable in addition to the simple stress myocardial perfusion imaging. (author)

[Clinical significance of myocardial 123I-BMIPP imaging in patients with myocardial infarction].

Science.gov (United States)

Narita, M; Kurihara, T; Shindoh, T; Honda, M

1997-03-01

In order to clarify the characteristics of fatty acid metabolism in patients with myocardial infarction (MI), we performed myocardial imaging with 123I-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) and we compared these findings with exercise stress (Ex) and resting myocardial perfusion imaging with 99mTc-methoxyisobutylisonitrile (MIBI) and left ventricular wall motion index (WMI) which were obtained by left ventriculography. We studied 55 patients with MI, 14 patients with recent MI (RMI) and 41 patients with old MI (OMI), and myocardial images were divided into 17 segments and myocardial uptake of the radionuclide was graded from 0 (normal) to 3 (maximal abnormality). In 28 patients we compared segmental defect score (SDS) with WMI which were obtained by centerline method at the corresponded segments. As a whole, the mean total defect scores (TDSs) of BMIPP and Ex were similar and they were greater than the mean TDS of resting perfusion. In 30 patient (55%) TDS of BMIPP was greater than that of TDS of resting perfusion. In 24 patients perfusion abnormality developed by Ex and the location of BMIPP abnormality coincided with the abnormality of Ex. But in the other 6 patients Ex did not induce any abnormality and they were all RMI and infarcted coronary artery was patent. However in the group with TDS of BMIPP identical to TDS of resting perfusion (25 patients), 92% did not show myocardial perfusion abnormality after Ex. In the comparison of SDS and WMI, myocardial segments were divided into 3 groups; both SDSs of BMIPP and resting perfusion were normal or borderline abnormality (Group 1, 82 segments), SDS of resting perfusion was normal or borderline and SDS of BMIPP was definitely abnormal (Group 2, 10 segments) and both SDSs of BMIPP and resting perfusion were definitely abnormal (Group 3, 48 segments). In Group 1, WMS (-0.41 +/- 0.77) was significantly (p acid metabolism may appear in viable myocardium such as jeopardized myocardium and myocardium which

Evaluation of Effects of Warning Sign Position on Driving Behavior in Horizontal Sharp Curves

Directory of Open Access Journals (Sweden)

Xiao-hua Zhao

2015-02-01

Full Text Available In present time, the guidelines on warning sign position in the China National Standard lack detailed and standard regulations of placing warning signs on sharp curves, which may cause road safety problems. Therefore, this paper briefly discussed how to optimize the position of a warning sign on a sharp curve through a driving simulator experiment. This study concluded that a warning sign placed at different positions prior to a sharp curve will have different influence ranges for drivers approaching and negotiating the curve. Meanwhile, different positions of a warning sign imposed different effect obviously on the adjustment of vehicle's lane position on sharp curves with the same radius, especially at the midpoint of a sharp curve. The evaluation results of five positions (0 m, 50 m, 100 m, 200 m, and 400 m in advance showed that only when the warning signs were placed 100 m or 200 m prior to sharp curves, can they achieve positive influence on driving behavior. On this basis, the authors look forward to providing rationalization proposals in selecting the best position of a warning sign on a sharp curve for the engineering implementation and national standard.

On the sharp front-type solution of the Nagumo equation with ...

Indian Academy of Sciences (India)

One of the methods is to solve the travelling wave equations and compute an exact solution which describes the sharp travelling wavefront. The second method is to solve numer- ically an initial-moving boundary-value problem for the partial differential equation and obtain an approximation for this sharp front-type solution.

Evaluation of myocardial abnormalities in patients with collagen diseases by thallium-201 myocardial scintigram

Energy Technology Data Exchange (ETDEWEB)

Yamano, Shigeru (Nara Medical Univ., Kashihara (Japan))

1992-08-01

This study was performed to evaluate myocardial lesions in patients with collagen diseases by rest and exercise thallium-201 myocardial scintigraphies. A total of 76 patients without ischemic ECG changes, consisting of 27 cases of systemic lupus erythematosus (SLE), 17 cases of polymyositis or dermatomyositis (PM[center dot]DM), 11 cases of progressive systemic sclerosis (PSS), and 21 cases of Sjoegren's syndrome (SjS), were enrolled in this study. Reversible exercise-induced defects suggesting myocardial ischemia were noted in 12 cases of SLE, 5 cases of PM[center dot]DM, 3 cases of PSS, and 3 cases of SjS. Of the 23 patients who had exercise-induced defects, 9 patients showed normal coronary angiograms by cardiac catheterization. Fixed hypoperfusion areas were observed in 5 cases of SLE, 6 cases of PM[center dot]DM, 4 cases of PSS and 3 cases of SjS. Rest thallium-201 myocardial scintigraphy disclosed hypoperfusion areas, which were not induced by exercise, in 1 case of SLE, 4 cases of PM[center dot]DM, 1 case of PSS and 5 cases of SjS. Endomyocardial biopsy was performed on 20 patients. Myocardial lesions in PM[center dot]DM and PSS were more severe and wide spread than in SLE. Ejection fraction and fractional shortening evaluated by echocardiography had no significant differences between each disease group and the healthy control group. These findings suggest that patients with collagen diseases show the presence of abnormalities of coronary circulation at the level of the intramyocardial vasculature in the stage before impairment of cardiac function, myocardial fibrosis and functional abnormalities of the cell membrane level that were not dependent on myocardial ischemia. (author).

The myocardial perfusion imaging of bone marrow mesenchymal stem cell transplantation treated acute myocardial infarction in pig

International Nuclear Information System (INIS)

He Miao; Hou Xiancun; Li Yaomei; Zhou Peng; Qi Chunmei; Wu Weihuan; Li Li

2006-01-01

Objective: To evaluate the clinical value of bone marrow mesenchymal stem cell transplantation on acute myocardial infarction in pig with myocardial perfusion imaging. Methods: Acute myocardial infarction models were established by 21 minitype Chinese pigs and were divided into two groups. After 10 days, experimental group (n=11) was transplanted with bone marrow mesenchymal stem cell at the infarct areas, and the control group (n=10) with incubation solution. Before and eight weeks after transplantation, both groups were examined by 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging and with semi-quantitative analysis. Besides, echocardiogram and immunohistochemistry were also performed. Results: There was significant difference of total myocardial perfusion abnormal segments (46 vs 26), infarct areas [(34±12)% vs (21±10)%] and myocardial ischemia score [(20.0±4.3) vs (12.1±3.6)] between two groups (P<0.05). Also, there were accordant results with echocardiogram and immunohistochemistry findings. Conclusions: Bone marrow mesenchymal stem cell transplantation may improve blood perfusion and viability of the ischemic areas: Myocardial perfusion imaging can accurately observe the survival of bone marrow mesenchymal stem cell transplanted at the infarct areas. (authors)

Characterization of Organic Materials in the Xenolithic Clasts in Sharps (H3.4) Meteorite Using Microraman Spectroscopy

Science.gov (United States)

Chan, Q. H. S.; Zolensky, M. E.; Bodnar, R. J.; Kebukawa, Y.

2015-01-01

Graphitization of carbon is an irreversible process which alters the structure of graphitic materials in response to the increase in metamorphic grade (temperature and/or pressure). Carbonaceous materials offer a reliable geothermometer as their Raman spectra change systematically with increasing metamorphic grade [1-3]. In this study, we identified carbonaceous materials in the xenolithic clasts in Sharps and interpreted their metamorphic history by revealing the structural organization (order) of the polyaromatic organic phases using µ-Raman spectroscopy.

Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies.

Science.gov (United States)

Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

2006-03-01

To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2 = 0.92 versus r2 = 0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (kappa = 0.87 v kappa = 0.75, p < 0.05). MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine.

Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

Science.gov (United States)

Kamat, Pranitha; Vandenberghe, Stijn; Christen, Stephan; Bongoni, Anjan K; Meier, Bernhard; Rieben, Robert; Khattab, Ahmed A

2016-01-01

Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R) injury during myocardial infarction (MI). Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS). We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5) or saline (n = 5) was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group) as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE), endothelial cell activation (CD31) and inflammation (IgG, C3b/c, C5b9, MCP-1) were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

Four year-old girl with having bled intestinal sharp

International Nuclear Information System (INIS)

Rodriguez Toro, Gerzain

2001-01-01

Indigenous girl, natural of Vaupes, Colombia conduction to the Mitu Hospital to present depositions with bleed. Their father says that the girl is sick for two days; she presents anorexia, moderate abdominal pain and vomit scarce postprandial, followed by discreet diarrhea and of two depositions with blood and abundant clots, with posterior syncope. It confirms a bled digestive with sharp anemic syndrome. The possibilities of gastritis sharp erosive, gastric ulcer or duodenal and intestinal poliparasitism are suggested. It is diagnosed abdominal angioestrongilosis, illness produce by helminths that lives inside the blind and the distal ileum

Sharp fronts within geochemical transport problems

International Nuclear Information System (INIS)

Grindrod, P.

1995-01-01

The authors consider some reactive geochemical transport problems in groundwater systems. When incoming fluid is in disequilibrium with the mineralogy sharp transition fronts may develop. They show that this is a generic property for a class of systems where the timescales associated with reaction and diffusion phenomena are much shorter than those associated with advective transport. Such multiple timescale problems are relevant to a variety of processes in natural systems: mathematically methods of singular perturbation theory reduce the dimension of the problems to be solved locally. Furthermore, they consider how spatial heterogeneous mineralogy can impact upon the propagation of sharp geochemical fronts. The authors developed an asymptotic approach in which they solve equations for the evolving geometry of the front and indicate how the non-smooth perturbations due to natural heterogeneity of the mineralogy on underlying ground water flow field are balanced against the smoothing effect of diffusion/dispersive processes. Fronts are curvature damped, and the results here indicate the generic nature of separate front propagation within both model (idealized) and natural (heterogeneous) geochemical systems

Importance of layer thermal conductivity on the sharpness of patterns produced by laser interference

Energy Technology Data Exchange (ETDEWEB)

Peláez, R.J., E-mail: rpelaez@io.cfmac.csic.es [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Afonso, C.N. [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Škereň, M. [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic); Bulíř, J. [Institute of Physics, ASCR, v.v.i., Na Slovance 2, Prague (Czech Republic)

2016-06-30

Highlights: • Temperature profile matches laser intensity profile in poor thermally conducting layers. • Patterns produced in poor thermally conducting layers have sharp interfaces. • Lateral heat flow smears the temperature profile in thermally conducting layers. • Both liquid and solid state dewetting occurs upon patterning thermally conducting layers. • The thermal conductivity of layers limits the minimum period achievable. - Abstract: In this work, we compare patterns produced in Ag layers having similar thickness in the range 8.3–10.8 nm but having different initial nanostructure, i.e. behaving either as discontinuous or continuous layers and thus having very different thermal conductivities. The patterns are produced by exposing a phase mask to an excimer laser operating at 193 nm and using a projection optics that leads to similar fringed patterns with periods in the range 6.3–6.7 μm. The layer breaks up into isolated NPs due to laser induced melting at the regions around the intensity maxima sites. The resulting fringes have sharp interfaces in the case of discontinuous layers while a variety of regions across the pattern with no sharp interfaces are produced in the case of continuous layers. The results show that while the temperature distribution across the pattern matches almost perfectly the laser beam intensity profile for the former case, it becomes smeared due to lateral heat flow for the latter case. These results provide evidences for significant heating at the intensity minima sites that lead to solid-state dewetting and will eventually limit the minimum period achievable in the case of continuous metal layers or thermally conducting layers.

Consideration of vision and picture quality: psychological effects induced by picture sharpness

Science.gov (United States)

Kusaka, Hideo

1989-08-01

A psychological hierarchy model of human vision(1)(2) suggests that the visual signals are processed in a serial manner from lower to higher stages: that is "sensation" - "perception" - "emotion." For designing a future television system, it is important to find out what kinds of physical factors affect the "emotion" experienced by an observer in front of the display. This paper describes the psychological effects induced by the sharpness of the picture. The subjective picture quality was evaluated for the same pictures with five different levels of sharpness. The experiment was performed on two kinds of printed pictures: (A) a woman's face, and (B) a town corner. From these experiments, it was found that the amount of high-frequency peaking (physical value of the sharpness) which psychologically gives the best picture quality, differs between pictures (A) and (B). That is, the optimum picture sharpness differs depending on the picture content. From these results, we have concluded that the psychophysical sharpness of the picture is not only determined at the stage of "perception" (e.g., resolution or signal to noise ratio, which everyone can judge immediately), but also at the stage of "emotion" (e.g., sensation of reality or beauty).

Weapon Use in Korean Homicide: Differences Between Homicides Involving Sharp and Blunt Instruments.

Science.gov (United States)

Park, Jisun; Son, Hyeonseo

2017-10-23

On the basis of information regarding 276 homicides committed in South Korea between 1987 and 2008, we compared offenders' and victims' characteristics, injury locations, weapon-related behavior, and offending behavior between homicides involving sharp and blunt instruments. The victims of sharp-force homicide were much younger relative to those of blunt-force homicide. In addition, homicides involving blunt instruments were more likely to be committed by offenders who lived with the victims. Most sharp-force homicides involved injuries to the torso, while blunt-force homicides involved mainly head injuries. Furthermore, perpetrators of sharp-force homicides tended to preselect their weapons, while those of blunt-force homicides were likely to use weapons of opportunity. Logistic regression analysis identified a number of factors, including injury location and body transportation, which significantly predicted weapon type. As this was the first South Korean study to compare sharp- and blunt-force homicides, the results have practical implications for homicide investigations. © 2017 American Academy of Forensic Sciences.

Weighting of field heights for sharpness and noisiness

Science.gov (United States)

Keelan, Brian W.; Jin, Elaine W.

2009-01-01

Weighting of field heights is important in cases when a single numerical value needs to be calculated that characterizes an attribute's overall impact on perceived image quality. In this paper we report an observer study to derive the weighting of field heights for sharpness and noisiness. One-hundred-forty images were selected to represent a typical consumer photo space distribution. Fifty-three sample points were sampled per image, representing field heights of 0, 14, 32, 42, 51, 58, 71, 76, 86% and 100%. Six observers participated in this study. The field weights derived in this report include both: the effect of area versus field height (which is a purely objective, geometric factor); and the effect of the spatial distribution of image content that draws attention to or masks each of these image structure attributes. The results show that relative to the geometrical area weights, sharpness weights were skewed to lower field heights, because sharpness-critical subject matter was often positioned relatively near the center of an image. Conversely, because noise can be masked by signal, noisiness-critical content (such as blue skies, skin tones, walls, etc.) tended to occur farther from the center of an image, causing the weights to be skewed to higher field heights.

Clinical Significance of Reverse Redistribution Phenomenon on Delayed Tc-99m Tetrofosmin Myocardial Perfusion Imaging in Patients with Acute Myocardial Infarction

International Nuclear Information System (INIS)

Park, Soon Ah; Kim, Dae Weung; Kim, Chang Guhn; Jeong, Jin Won; Kim, Nam Ho; Yun, Kyeong Ho

2009-01-01

This study was performed to investigate the clinical significance of reverse redistribution (RR) phenomenon detected on delayed Tc-99m tetrofosmin myocardial single photon emission computed tomography (SPECT) in patients with acute myocardial infarction after revascularization. A Tc-99m tetrofrosmin myocardial SPECT was performed in 67 consecutive patients after revascularization for acute myocardial infarction. Myocardial SPECT imaging was performed for early imaging at 40 min and for delayed imaging at 180 min after reinjection at myocardial stress. Regional myocardial uptakes were scored by 4-point scoring in the left ventricular wall divided into 17 segments. Reverse redistribution was defined as an increase of more than 2 point in the activity score on the delayed image. Follow-up myocardial SPECT and coronary angiography (CAG) were performed 9 months later. On myocardial SPECT performed following revascularization, RR was observed in 100 of all 319 segments (31%) and in 43 patients (64%). The abnormalities of perfusion and regional wall motion were more severe in the patients with RR compared to those without RR (p<0.05). On follow-up myocardial SPECT, the myocardial perfusion, regional wall motion, and myocardial thickness were significantly improved in the patients with RR (p<0.05) however, these changes were not significant in those without RR. There was no significant difference between the patients with RR and those without RR in the occurrence of restenosis on CAG. In patients with acute myocardial infarction, the regions showing the RR phenomenon on delayed Tc-99m tetrofosmin SPECT may reflect viable myocardium and indicate recovery of salvaged myocardium

Characterization of Organic Materials in the Xenolithic Clasts in Sharps (H3.4) Meteorite Using Micro-Raman Spectroscopy

Science.gov (United States)

Chan, Q. H. S.; Zolensky, M. E.; Bodnar, R. J.; Kebukawa, Y.

2015-01-01

Graphitization of carbon is an irreversible process which alters the structure of graphitic materials in response to the increase in metamorphic grade (temperature and/or pressure). Carbonaceous materials offer a reliable geothermometer as their Raman spectra change systematically with increasing metamorphic grade. In this study, we identified carbonaceous materials in the xenolithic clasts in Sharps and interpreted their metamorphic history by revealing the structural organization (order) of the polyaromatic organic phases using micro-Raman spectroscopy.

On the stress calculation within phase-field approaches: a model for finite deformations

Science.gov (United States)

Schneider, Daniel; Schwab, Felix; Schoof, Ephraim; Reiter, Andreas; Herrmann, Christoph; Selzer, Michael; Böhlke, Thomas; Nestler, Britta

2017-08-01

Numerical simulations based on phase-field methods are indispensable in order to investigate interesting and important phenomena in the evolution of microstructures. Microscopic phase transitions are highly affected by mechanical driving forces and therefore the accurate calculation of the stresses in the transition region is essential. We present a method for stress calculations within the phase-field framework, which satisfies the mechanical jump conditions corresponding to sharp interfaces, although the sharp interface is represented as a volumetric region using the phase-field approach. This model is formulated for finite deformations, is independent of constitutive laws, and allows using any type of phase inherent inelastic strains.

Inflammatory and apoptotic remodeling in autonomic nervous system following myocardial infarction.

Directory of Open Access Journals (Sweden)

Chen Gao

Full Text Available Chronic myocardial infarction (MI triggers pathological remodeling in the heart and cardiac nervous system. Abnormal function of the autonomic nervous system (ANS, including stellate ganglia (SG and dorsal root ganglia (DRG contribute to increased sympathoexcitation, cardiac dysfunction and arrythmogenesis. ANS modulation is a therapeutic target for arrhythmia associated with cardiac injury. However, the molecular mechanism involved in the pathological remodeling in ANS following cardiac injury remains to be established.In this study, we performed transcriptome analysis by RNA-sequencing in thoracic SG and (T1-T4 DRG obtained from Yorkshire pigs following either acute (3 to 5 hours or chronic (8 weeks myocardial infarction. By differential expression and weighted gene co-expression network analysis (WGCNA, we identified significant transcriptome changes and specific gene modules in the ANS tissues in response to myocardial infarction at either acute or chronic phases. Both differential expressed genes and the member genes of the WGCNA gene module associated with post-infarct condition were significantly enriched for inflammatory signaling and apoptotic cell death. Targeted validation analysis supported a significant induction of inflammatory and apoptotic signal in both SG and DRG following myocardial infarction, along with cellular evidence of apoptosis induction based on TUNEL analysis. Importantly, these molecular changes were observed specifically in the thoracic segments but not in their counterparts obtained from lumbar sections.Myocardial injury leads to time-dependent global changes in gene expression in the innervating ANS. Induction of inflammatory gene expression and loss of neuron cell viability in SG and DRG are potential novel mechanisms contributing to abnormal ANS function which can promote cardiac arrhythmia and pathological remodeling in myocardium.

Quantitative assessment of 201TlCl myocardial SPECT

International Nuclear Information System (INIS)

Uehara, Toshiisa

1987-01-01

Clinical evaluation of the quantitative analysis of Tl-201 myocardial tomography by SPECT (Single Photon Emission Computed Tomography) was performed in comparison with visual evaluation. The method of quantitative analysis has been already reported in our previous paper. In this study, the program of re-standardization in the case of lateral myocardial infarction was added. This program was useful mainly for the evaluation of lesions in the left circumflex coronary artery. Regarding the degree of diagnostic accuracy of myocardial infarction in general, quantitative evaluation of myocardial SPECT images was highest followed by visual evaluation of myocardial SPECT images, and visual evaluation of myocardial planar images. However, in the case of anterior myocardial infarction, visual evaluation of myocardial SPECT images has almost the same detectability as quantitative evaluation of myocardial SPECT images. In the case of infero-posterior myocardial infarction, quantitative evaluation was superior to visual evaluation. As for specificity, quantitative evaluation of SPECT images was slightly inferior to visual evaluation of SPECT images. An infarction map was made by quantitative analysis and this enabled us to determine the infarction site, extent and degree according to easily recognizable patterns. As a result, the responsible coronary artery lesion could be inferred correctly and the calculated infarction score could be correlated with the residual left ventricular function after myocardial infarction. (author)

Noninvasive assessment of canine myocardial oxidative metabolism with carbon-11 acetate and positron emission tomography

International Nuclear Information System (INIS)

Brown, M.A.; Myears, D.W.; Bergmann, S.R.

1988-01-01

Noninvasive quantification of regional myocardial metabolism would be highly desirable to evaluate pathogenetic mechanisms of heart disease and their response to therapy. It was previously demonstrated that the metabolism of radiolabeled acetate, a readily utilized myocardial substrate predominantly metabolized to carbon dioxide (CO2) by way of the tricarboxylic acid cycle, provides a good index of oxidative metabolism in isolated perfused rabbit hearts because of tight coupling between the tricarboxylic acid cycle and oxidative phosphorylation. In the present study, in a prelude to human studies, the relation between myocardial clearance of carbon-11 (11C)-labeled acetate and myocardial oxygen consumption was characterized in eight intact dogs using positron emission tomography. Anesthetized dogs were studied during baseline conditions and again during either high or low work states induced pharmacologically. High myocardial extraction and rapid blood clearance of tracer yielded myocardial images of excellent quality. The turnover (clearance) of 11C radioactivity from the myocardium was biexponential with the mean half-time of the dominant rapid phase averaging 5.4 +/- 2.2, 2.8 +/- 1.3 and 11.1 +/- 1.3 min in control, high and low work load studies, respectively. No significant difference was found between the rate of clearance of 11C radioactivity from the myocardium measured noninvasively with positron emission tomography and the myocardial efflux of 11CO2 measured directly from the coronary sinus. The rate of clearance of the 11C radioactivity from the heart correlated closely with myocardial oxygen consumption (r = 0.90, p less than 0.001) as well as with the rate-pressure product (r = 0.95, p less than 0.001). Hence, the rate of oxidation of 11C-acetate can be determined noninvasively with positron emission tomography, providing a quantitative index of oxidative metabolism under diverse conditions

Effect of nicorandil on the myocardial tissue perfusion and myocardial cell injury in patients with diabetes after PCI

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Xue-Li Ren1

2017-04-01

Full Text Available Objective: To study the effect of nicorandil on the myocardial tissue perfusion and myocardial cell damage in patients with diabetes after percutaneous coronary intervention (PCI. Methods: 68 patients with coronary heart disease and type 2 diabetes mellitus who received PCI in our hospital between May 2011 and September 2015 were collected and then divided into observation group and control group (n=34 according to the single-blind randomized control method. Control group of patients received PCI alone, and the observation group of patients received nicorandil therapy after PCI. After treatment, real-time myocardial ultrasound contrast was used to evaluate the myocardial perfusion of two groups of patients; blood biochemical analyzer was used to detect the contents of peripheral blood myocardial enzyme spectrum indexes; the ELISA method was used to detect the contents of serum oxidative stress indicators; RIA method was used to detect the contents of serum apoptosis molecules. Results: After treatment, the myocardial tissue perfusion parameters plateau peak intensity (A, slope rate of curve (β and myocardial blood flow (A×β levels of observation group were significantly higher than those of control group (P<0.05; peripheral blood myocardial enzyme spectrum indexes creatine kinase (CK, lactate dehydrogenase (LDH, troponin I (cTnI and glutamic oxalacetic transaminase (GOT contents of observation group were significantly lower than those of control group (P<0.05; serum vitamin E (VitE and vitamin C (VitC contents of observation group were significantly higher than those of control group while malondialdehyde (MDA, advanced oxidation protein products (AOPPs, soluble apoptosis-associated factor (sFas and soluble apoptosis-associated factor ligand (sFasL contents were lower than those of control group (P<0.05. Conclusion: Adjuvant nicorandil therapy can improve the myocardial perfusion and reduce the myocardial cell injury in patients with coronary

The effectiveness of sharp end and rounded end bristle toothbrush

OpenAIRE

Paulus Januar; Anastasia Susetyo; Ratih Widyastuti

2010-01-01

Background: Numerous designs of manual toothbrush are available in the market with the claims of superiority in plaque removal. It often makes the public confuse which is the best design. The sharp end bristle toothbrush is a modification that commercially available in the market. Purpose: The objective of the study was to compare the effectiveness in plaque removal of the sharp end bristle toothbrush and the rounded end bristle toothbrush. Methods: This clinical trial was a double blind cros...

Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

International Nuclear Information System (INIS)

Tamura, Takuhisa; Shibuya, Noritoshi; Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke.

1993-01-01

Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD≥10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD≥10 and age≥15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age≥15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author)

PRACTICES FOR PREVENTION NEEDLESTICK AND SHARPS INJURIES AMONG NURSING STUDENTS

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Anh Tran Thi Quynh

2017-07-01

Full Text Available Background: Needlestick and sharp injuries are a serious hazard in any health care setting for health care workers and students during clinical practice. Thus, the efforts to prevent the needlestick and sharps injuries are needed and considered a part of the routine practice. Objective: This study aimed to investigate the frequency of nursing students in doing the correct practice in prevention needlestick and sharps injuries. Methods: This cross- sectional study was conducted between 2013 and 2014 in nursing students of Tien Giang Medical College who participated in clinical practice. There were 360 students participated in the study using simple random sampling. Data were collected using the practical assessment checklist and demographic characteristics questionnaire. Data were processed using STATA 12.0, and analyzed using Chi-square and Fisher test. Results: The students who did general practice correctly accounted for 52.50%, and those who did practice incorrectly was 47.5%. The students who used gauze or wool wrap in inhaler were 59.7%, wearing gloves in practice (39.2%, do not disassemble needles from syringes after injection 50%, and removing needles into barrel after injection (65.6%. There was statistically significant relationship between time of participation in clinical practice and correct practice with p-value 0.04 (<0.05 Conclusion: The correct practice of nursing students related to the prevention of needlestick and sharps injuries remains low. There was a significant relationship between time of participation in clinical practice and correct nursing practice. It is suggested that students must be taught about the risk of infection at the beginning of clinical practice, and constantly reminded throughout the learning process, especially for injection safety awareness, knowledge and techniques about the risk of transmission of HBV, HCV and HIV by sharp objects in the healthcare facility.

Dexrazoxane Shows No Protective Effect in the Acute Phase of Reperfusion during Myocardial Infarction in Pigs.

Directory of Open Access Journals (Sweden)

Pranitha Kamat

Full Text Available Calcium and iron overload participate in the mechanisms of ischemia/reperfusion (I/R injury during myocardial infarction (MI. Calcium overload induces cardiomyocyte death by hypercontraction, while iron catalyses generation of reactive oxygen species (ROS. We therefore hypothesized that dexrazoxane, an intracellular metal chelator, would attenuate I/R injury. MI was induced in pigs by occlusion of the left anterior descending artery for 1 hour followed by 2 hours reperfusion. Thirty minutes before reperfusion either 5 mg/ml dexrazoxane (n = 5 or saline (n = 5 was infused intravenously. Myocardial necrosis as percentage of the area at ischemic risk was found to be similar in both groups (77.2 ± 18% for dexrazoxane and 76.4 ± 14% for saline group as determined by triphenyl tetrazolium chloride staining of the ischemic myocardium. Also, serum levels of troponin-I were similar in both groups. A conductance catheter was used to measure left ventricular pressure and volume at all times. Markers for tissue damage due to ROS (HNE, endothelial cell activation (CD31 and inflammation (IgG, C3b/c, C5b9, MCP-1 were assessed on tissue and/or in serum. No significant differences were observed between the groups for the parameters analyzed. To conclude, in this clinically relevant model of early reperfusion after acute myocardial ischemia, dexrazoxane lacked attenuating effects on I/R injury as shown by the measured parameters.

Age Is Associated with Reduced Sharp-Wave Ripple Frequency and Altered Patterns of Neuronal Variability.

Science.gov (United States)

Wiegand, Jean-Paul L; Gray, Daniel T; Schimanski, Lesley A; Lipa, Peter; Barnes, C A; Cowen, Stephen L

2016-05-18

Spatial and episodic memory performance declines with age, and the neural basis for this decline is not well understood. Sharp-wave ripples are brief (∼70 ms) high-frequency oscillatory events generated in the hippocampus and are associated with the consolidation of spatial memories. Given the connection between ripple oscillations and memory consolidation, we investigated whether the structure of ripple oscillations and ripple-triggered patterns of single-unit activity are altered in aged rats. Local field and single-unit activity surrounding sharp-wave ripple events were examined in the CA1 region of the hippocampus of old (n = 5) and young (n = 6) F344 rats during periods of rest preceding and following performance on a place-dependent eyeblink-conditioning task. Neural responses in aged rats differed from responses in young rats in several ways. First, compared with young rats, the rate of ripple occurrence (ripple density) is reduced in aged rats during postbehavior rest. Second, mean ripple frequency during prebehavior and postbehavior rest is lower in aged animals (aged: 132 Hz; young: 146 Hz). Third, single neurons in aged animals responded more consistently from ripple to ripple. Fourth, variability in interspike intervals was greater in aged rats. Finally, neurons were tuned to a narrower range of phases of the ripple oscillation relative to young animals. Together, these results suggest that the CA1 network in aged animals has a reduced "vocabulary" of available representational states. The hippocampus is a structure that is critical for the formation of episodic memories. Sharp-wave ripple events generated in the hippocampus have been implicated in memory consolidation processes critical to memory stabilization. We examine here whether these ripple oscillations are altered over the course of the life span, which could contribute to hippocampus-dependent memory deficits that occur during aging. This experiment used young and aged memory-impaired rats

[Reduction of in-hospital mortality and improved secondary prevention after acute myocardial infarction. First results from the registry of secondary prevention after acute myocardial infarction (SAMI)].

Science.gov (United States)

Tebbe, U; Messer, C; Stammwitz, E; The, G S; Dietl, J; Bischoff, K-O; Schulten-Baumer, U; Tebbenjohanns, J; Gohlke, H; Bramlage, P

2007-07-30

In hospital mortality of acute myocardial infarction (AMI) has been reduced due to the availability of better therapeutic strategies. But there is still a gap between mortality rates in randomised trials and daily clinical practice. Thus, it was aim of the present registry to document the course and outcome of patients with AMI and to improve patient care by implementing recent guidelines. In a nationwide registry study in hospitals in Germany with a cardiology unit or an internal medicine department data on consecutive patients were recorded for six to twelve months at admission, discharge and during a follow-up of one year. From 02/2003 until 10/2004 a total of 5,353 patients with acute myocardial infarction (65.7 % male, mean age of 67.6 +/- 17.7 years; 55.1 % of them with ST elevation myocardial infarction (STEMI) were included in the registry. Of the patients with STEMI, 76.6 % underwent acute intervention, 37.1 % had thrombolysis, 69.7 % percutaneous transluminal coronary angioplasty (PTCA). 40.0 % of those with non-Stemi (NSTEMI) had an acute intervention, 6.6 % thrombolysis, 73.5 % PTCA. Recommended secondary prevention consisted of ASS (93.2 %), beta-blockers (93.0 %), CSE-inhibitors (83.5 %), ACE-inhibitors (80.9 %) and clopidogrel (74.0 %). In-hospital mortality was 10.5 % (STEMI) and 7.4 % (NSTEMI). The 9 % mortality among patients with acute myocardial infarction treated in the hospitals participating in the SAMI registry is low compared to that in similar collectives. The high number of patients who had thrombofibrinolysis and coronary interventions as well as the early initiation of drug therapy contributed to these results. Medical treatment in the prehospital phase of these patients remains still insufficient and to a substantial extent contributes to the mortality of acute myocardial infarction.

SHARP: A multi-mission artificial intelligence system for spacecraft telemetry monitoring and diagnosis

Science.gov (United States)

Lawson, Denise L.; James, Mark L.

1989-01-01

The Spacecraft Health Automated Reasoning Prototype (SHARP) is a system designed to demonstrate automated health and status analysis for multi-mission spacecraft and ground data systems operations. Telecommunications link analysis of the Voyager 2 spacecraft is the initial focus for the SHARP system demonstration which will occur during Voyager's encounter with the planet Neptune in August, 1989, in parallel with real time Voyager operations. The SHARP system combines conventional computer science methodologies with artificial intelligence techniques to produce an effective method for detecting and analyzing potential spacecraft and ground systems problems. The system performs real time analysis of spacecraft and other related telemetry, and is also capable of examining data in historical context. A brief introduction is given to the spacecraft and ground systems monitoring process at the Jet Propulsion Laboratory. The current method of operation for monitoring the Voyager Telecommunications subsystem is described, and the difficulties associated with the existing technology are highlighted. The approach taken in the SHARP system to overcome the current limitations is also described, as well as both the conventional and artificial intelligence solutions developed in SHARP.

Re-initiating professional working activity after myocardial infarction in primary percutaneous coronary intervention networks era

Directory of Open Access Journals (Sweden)

Zdravko Babić

2015-12-01

Full Text Available Objectives: To investigate the aspects of return to work, socio-economic and quality of life aspects in 145 employed patients under 60 years of age treated with primary percutaneous coronary intervention for acute ST-elevation myocardial infarction. Material and Methods: During hospital treatment demographic and clinical data was collected. Data about major adverse cardiovascular events, rehabilitation, sick leave, discharge from job and retirement, salary, major life events and estimation of quality of life after myocardial infarction were obtained after follow-up (mean: 836±242 days. Results: Average sick leave was 126±125 days. Following myocardial infarction, 3.4% of patients were discharged from their jobs while 31.7% retired. Lower salary was reported in 17.9% patients, major life events in 9.7%, while 40.7% estimated quality of life as worse following the event. Longer hospitalization was reported in patients transferred from surrounding counties, those with inferior myocardial wall and right coronary artery affected. Age, hyperlipoproteinemia and lower education degree were connected to permanent working cessation. Significant salary decrease was observed in male patients. Employer type was related to sick leave duration. Impaired quality of life was observed in patients who underwent in-hospital rehabilitation and those from surrounding counties. Longer sick leave was observed in patients with lower income before and after myocardial infarction. These patients reported lower quality of life after myocardial infarction. Conclusions: Inadequate health policy and delayed cardiac rehabilitation after myocardial infarction may lead to prolonged hospitalization and sick leave as well as lower quality of life after the event, regardless of optimal treatment in acute phase of disease.

Re-initiating professional working activity after myocardial infarction in primary percutaneous coronary intervention networks era.

Science.gov (United States)

Babić, Zdravko; Pavlov, Marin; Oštrić, Mirjana; Milošević, Milan; Misigoj Duraković, Marjeta; Pintarić, Hrvoje

2015-01-01

To investigate the aspects of return to work, socio-economic and quality of life aspects in 145 employed patients under 60 years of age treated with primary percutaneous coronary intervention for acute ST-elevation myocardial infarction. During hospital treatment demographic and clinical data was collected. Data about major adverse cardiovascular events, rehabilitation, sick leave, discharge from job and retirement, salary, major life events and estimation of quality of life after myocardial infarction were obtained after follow-up (mean: 836±242 days). Average sick leave was 126±125 days. Following myocardial infarction, 3.4% of patients were discharged from their jobs while 31.7% retired. Lower salary was reported in 17.9% patients, major life events in 9.7%, while 40.7% estimated quality of life as worse following the event. Longer hospitalization was reported in patients transferred from surrounding counties, those with inferior myocardial wall and right coronary artery affected. Age, hyperlipoproteinemia and lower education degree were connected to permanent working cessation. Significant salary decrease was observed in male patients. Employer type was related to sick leave duration. Impaired quality of life was observed in patients who underwent in-hospital rehabilitation and those from surrounding counties. Longer sick leave was observed in patients with lower income before and after myocardial infarction. These patients reported lower quality of life after myocardial infarction. Inadequate health policy and delayed cardiac rehabilitation after myocardial infarction may lead to prolonged hospitalization and sick leave as well as lower quality of life after the event, regardless of optimal treatment in acute phase of disease. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT, HVLP COATING EQUIPMENT, SHARPE MANUFACTURING COMPANY PLATINUM 2012 HVLP SPRAY GUN

Science.gov (United States)

This report presents the results of the verification test of the Sharpe Platinum 2013 high-volume, low-pressure gravity-feed spray gun, hereafter referred to as the Sharpe Platinum, which is designed for use in automotive refinishing. The test coating chosen by Sharpe Manufacturi...

Detecting Myocardial Ischemia With 99mTechnetium-Tetrofosmin Myocardial Perfusion Imaging in Ischemic Stroke.

Science.gov (United States)

Giannopoulos, Sotirios; Markoula, Sofia; Sioka, Chrissa; Zouroudi, Sofia; Spiliotopoulou, Maria; Naka, Katerina K; Michalis, Lampros K; Fotopoulos, Andreas; Kyritsis, Athanassios P

2017-10-01

To assess the myocardial status in patients with stroke, employing myocardial perfusion imaging (MPI) with 99m Technetium-tetrofosmin ( 99m Tc-TF)-single-photon emission computed tomography (SPECT). Fifty-two patients with ischemic stroke were subjected to 99m Tc-TF-SPECT MPI within 1 month after stroke occurrence. None of the patients had any history or symptoms of coronary artery disease or other heart disease. Myocardial perfusion imaging was evaluated visually using a 17-segment polar map. Myocardial ischemia (MIS) was defined as present when the summed stress score (SSS) was >4; MIS was defined as mild when SSS was 4 to 8, and moderate/severe with SSS ≥9. Patients with SSS >4 were compared to patients with SSS SSS >9 were compared to patients with SSS SSS, with the oldest age exhibiting the highest SSS ( P = .01). The association of age with SSS remained statistically significant in the multivariate analysis ( P = .04). The study suggested that more than half of patients with stroke without a history of cardiac disease have MIS. Although most of them have mild MIS, we suggest a thorough cardiological evaluation in this group of patients for future prevention of severe myocardial outcome.

Ventricular and myocardial scintiscanning: Methodical fundamentals

International Nuclear Information System (INIS)

Standke, R.; Hoer, G.; Maul, F.D.

1984-01-01

Nuclear cardiology is concerned with non invasive procedures to quantitate global and regional left ventricular function (Radionuclide ventriculography), also the imaging of vitally perfused myocardium (Myocardial scintigraphy) is achieved. A gammacamera and a minicomputer are necessary. Radionuclide ventriculography enables the analysis of global and regional time dependent left ventricular volume curves and hence the evaluation of contraction and contractility of the heart muscle. The basis is a sequence of scans covering an average heartcycle. This sequence may be produced either by first pass or equilibrium technique. Myocardial scintigraphy at rest images vital myocardium, scans immediately after exercise represent the interference of myocardial perfusion and muscle mass. The regional difference (Redistribution) between normalized exercise- and rest scans provide quantitative parameters to detect impairment of exercise-induced myocardial perfusion anomalies. The procedures of sectorial analysis of left ventricular function and myocardial perfusion are presented. (orig.) [de

SHARP - a framework for incorporating human interactions into PRA studies

International Nuclear Information System (INIS)

Hannaman, G.W.; Joksimovich, V.; Spurgin, A.J.; Worledge, D.H.

1985-01-01

Recently, increased attention has been given to understanding the role of humans in the safe operation of nuclear power plants. By virtue of the ability to combine equipment reliability with human reliability probabilistic risk assessment (PRA) technology was deemed capable of providing significant insights about the contributions of human interations in accident scenarios. EPRI recognized the need to strengthen the methodology for incorporating human interactions into PRAs as one element of their broad research program to improve the credibility of PRAs. This research project lead to the development and detailed description of SHARP (Systematic Human Application Reliability Procedure) in EPRI NP-3583. The objective of this paper is to illustrate the SHARP framework. This should help PRA analysts state more clearly their assumptions and approach no matter which human reliability assessment technique is used. SHARP includes a structure of seven analysis steps which can be formally or informally performed during PRAs. The seven steps are termed definition, screening, breakdown, representation, impact assessment, quantification, and documentation

Evaluation of right and left ventricular function in the patients with myocardial infarction using quantitative radionuclide cardioangiography

International Nuclear Information System (INIS)

Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Ohmine, Hiromi; Kozuka, Takahiro

1984-01-01

We evaluated right and left ventricular function in the case of myocardial infarction (MI) by radionuclide cardioangiography. The right and left ventricular ejection fraction (RVEF, LVEF) and ventricular volume (RVEDV, LVEDV) were calculated. And, phase and amplitude images were also obtained from gated blood pool scan. There were 60 cases of MI (35 anterior MI, 17 inferior MI and 8 right ventricular MI) and 10 normal cases. The LVEF was depressed in anterior MI (36 +- 14%) and RVEF was depressed in right ventricular MI (37 +- 5%). In addition, LVEDV was increased in anterior MI (163 +- 47 ml) and RVEDV increased in right ventricular MI (208 +- 33 ml), respectively. The amplitude of infarcted area was decreased. And the phase angle of LV was delayed in anterior MI and that of RV was delayed in right ventricular MI. Therefore, in the case of right ventricular MI, the depression of LVEF and RVEF was caused by the biventricular myocardial damage. And the cross talk phenomenon of biventricle was rarely observed, since the lung acts as the buffer between RV and LV. In conclusion, these noninvasive, methods provide useful information on the biventricular function in the case of myocardial infarction. (author)

Myocardial glucose metabolism in patients with hypertrophic cardiomyopathy. Assessment by F-18-FDG PET study

International Nuclear Information System (INIS)

Uehara, Toshiisa; Ishida, Yoshio; Hayashida, Kohei

1998-01-01

In an investigation of myocardial metabolic abnormalities in hypertrophic myocardium, the myocardial glucose metabolism was evaluated with F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) in 32 patients with hypertrophic cardiomyopathy, and the results were compared with those in 9 patients with hypertensive heart disease. F-18-FDG PET study was performed in the fasting and glucose-loading states. The myocardial regional %dose uptake was calculated quantitatively. The average regional %dose uptake in the fasting state in the patients with asymmetric septal hypertrophy and dilated-phase hypertrophic cardiomyopathy was significantly higher than that in the patients with hypertensive heart disease (0.75±0.34%, 0.65±0.25%, and 0.43±0.22%/100 g myocardium, respectively). In contrast, the average %dose uptake in the glucose-loading state in the patients with asymmetric septal hypertrophy and dilated-phase hypertrophic cardiomyopathy was not significantly different from that in patients with hypertensive heart disease (1.17±0.49%, 0.80±0.44% and 0.99±0.45%, respectively). The patients with apical hypertrophy had also low %dose uptake in the fasting state (0.38±0.21%) as in the hypertensive heart disease patients, so that the characteristics of asymmetric septal hypertrophy and dilated-phase hypertrophic cardiomyopathy are considered to be high FDG uptake throughout the myocardium in the fasting state. Patients with apical hypertrophy are considered to belong to other disease categories metabolically. F-18-FDG PET study is useful in the evaluation of the pathophysiologic diagnosis of patients with hypertrophic cardiomyopathy. (author)

Myocardial scintigraphy with /sup 201/Tl and quantitative assessment of myocardial blood flow

Energy Technology Data Exchange (ETDEWEB)

Ishii, Y; Kanbara, H; Yonekura, Y; Kadota, K; Fujita, T [Kyoto Univ. (Japan). Faculty of Medicine

1976-12-01

A newly introduced radionuclide for myocardial imaging, /sup 201/Tl, was studied. Twenty-two subjects consisting of 7 normals, 12 with ischemic heart disease and 3 with hypertrophic cardiomyopathy (HCM) were selected. On intravenous administration of /sup 201/Tl(1.5 to 20. mCi), initial transit of the tracer through the heart, as well as subsequent uptake by the myocardium, were recorded by a scintillation camera. The later process showed the distribution of the myocardial blood flow (MBF). A normal myocardial scintigraphy revealed the left-sided myocardial mass predominantly, whereas the right side or the septum predominated in the case of tetralogy of fallot (T/F) or idiopathic hypertrophic subuaortic stenosis (IHSS). An ischemic or infarcted area of the myocardium in ischemic heart disease (IHD) was compatible with electrocardiographic findings, and revealed defects even in an equivocal case on ECG. Since the ratio of radioactivity taken up by the myocardium (U) to the total injected dosis (I) is assumed to be proportional to the fractional MBF of cardiac output (CO), MBF/CO is calculated by ratio of the radioactivity selected from myocardial region on the later recording to that from the entire region on the initial transit of the tracer bolus. The average MBF/CO of normals was 4.4 +- 0.5%, IHD 4.0 +- 0.8% and HCM 5.5 +- 1.2%. On exercise loading, a significant increase of this value was observed in normals, whereas no change was observed in IHD.

Understanding sharps injuries in home healthcare: The Safe Home Care qualitative methods study to identify pathways for injury prevention.

Science.gov (United States)

Markkanen, Pia; Galligan, Catherine; Laramie, Angela; Fisher, June; Sama, Susan; Quinn, Margaret

2015-04-11

Home healthcare is one of the fastest growing sectors in the United States. Percutaneous injuries from sharp medical devices (sharps) are a source of bloodborne pathogen infections among home healthcare workers and community members. Sharps use and disposal practices in the home are highly variable and there is no comprehensive analysis of the system of sharps procurement, use and disposal in home healthcare. This gap is a barrier to effective public health interventions. The objectives of this study were to i) identify the full range of pathways by which sharps enter and exit the home, stakeholders involved, and barriers for using sharps with injury prevention features; and ii) assess the leverage points for preventive interventions. This study employed qualitative research methods to develop two systems maps of the use of sharps and prevention of sharps injuries in home healthcare. Twenty-six in-depth interview sessions were conducted including home healthcare agency clinicians, public health practitioners, sharps device manufacturers, injury prevention advocates, pharmacists and others. Interview transcripts were audio-recorded and analyzed thematically using NVIVO qualitative research analysis software. Analysis of supporting archival material also was conducted. All findings guided development of the two maps. Sharps enter the home via multiple complex pathways involving home healthcare providers and home users. The providers reported using sharps with injury prevention features. However, home users' sharps seldom had injury prevention features and sharps were commonly re-used for convenience and cost-savings. Improperly discarded sharps present hazards to caregivers, waste handlers, and community members. The most effective intervention potential exists at the beginning of the sharps systems maps where interventions can eliminate or minimize sharps injuries, in particular with needleless treatment methods and sharps with injury prevention features

Acute myocardial infarction: susceptibility-weighted cardiac MRI for the detection of reperfusion haemorrhage at 1.5 T

International Nuclear Information System (INIS)

Durighel, G.; Tokarczuk, P.F.; Karsa, A.; Gordon, F.; Cook, S.A.; O'Regan, D.P.

2016-01-01

Aim: To assess whether susceptibility-weighted imaging (SWI) provides better image contrast for the detection of haemorrhagic ischaemia–reperfusion injury in the heart. Materials and methods: Thirty patients (all men; mean age 53 years) underwent cardiac magnetic resonance imaging (MRI) within 7 days of primary percutaneous intervention for acute ST elevation myocardial infarction (STEMI). Multiple gradient-echo T2* sequences with magnitude and phase reconstructions were acquired. A high-pass filtered phase map was used to create a mask for the SWI reconstructions. The difference in image contrast was assessed in those patients with microvascular obstruction. A mixed effects regression model was used to test the effect of echo time and reconstruction method on phase and contrast-to-noise ratio (CNR). Medians and interquartile ranges (IQR) are reported. Results: T2* in haemorrhagic infarcts was shorter than in non-haemorrhagic infarcts (33.5 ms [24.9–43] versus 49.9 ms [44.6–67.6]; p=0.0007). The effect of echo time on phase was significant (p<0.0001), as was the effect of haemorrhage on phase (p=0.0016). SWI reconstruction had a significant effect on the CNR at all echo times (echoes 1–5, p<0.0001; echo 6, p=0.01; echo 7, p=0.02). The median echo number at which haemorrhage was first visible was less for SWI compared to source images (echo 2 versus echo 5, p=0.0002). Conclusion: Cardiac SWI improves the contrast between myocardial haemorrhage and the surrounding tissue following STEMI and has potential as a new tool for identifying patients with ischaemia–reperfusion injury. - Highlights: • Cardiac susceptibility-weighted imaging (SWI) is feasible at 1.5T. • Combining phase and modulus data allows blood products to be seen at shorter echo times. • This sequence improves visualisation of reperfusion myocardial haemorrhage.

Background and design of the ACCA-EAPCI registry on ST-segment elevation myocardial infarction of the European Society of Cardiology.

Science.gov (United States)

Zeymer, Uwe; Ludman, Peter; Danchin, Nicolas; Kala, Petr; Maggioni, Aldo P; Weidinger, Franz

2018-02-01

Treatment of patients with acute ST-segment elevation myocardial infarction has improved over past decades, with reperfusion therapy being the cornerstone in the acute phase. Based on the results of large randomised trials the current ST-segment elevation myocardial infarction guidelines of the European Society of Cardiology (ESC) recommend acute treatments and secondary prevention therapies. However, there are large variations between ESC countries in the treatment of patients presenting with ST-segment elevation myocardial infarction. Therefore the ESC has initiated a prospective registry to evaluate the current treatments and outcomes of these patients with a special focus on adherence to the ESC guidelines and on differences between countries and regions. This paper describes the methodology and design of the ST-segment elevation myocardial infarction registry conducted in collaboration of the Acute Cardiac Care Association and the European Association of Percutaneous Coronary Intervention.

Quantitative relationships between thallium-201 estimated myocardial infarct size and left ventricular function in the acute or convalescent phase of the first attack of myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Kataoka, Hajime (Kagoshima Univ. (Japan). Faculty of Medicine); Ueda, Keiji; Sakai, Makoto (and others)

1983-07-01

Correlations between left ventricular (LV) function and infarct size estimated by computer-assisted thallium (Tl)-201 scintigraphy were studied in 16 patients in the acute or convalescent phase of the first attack of transmural myocardial infarction (MI). Tl-201 estimation of the infarct size was done using a ''corrected'' circumferential profile method, by which the total defect score could be obtained. The LV function was evaluated by radionuclide angiography, echocardiography and cardiac catheterization study. The following results were obtained: 1) A close inverse relationship was found between the defect score and the ejection fraction (r = -0.649, p < 0.01). 2) The linear correlation coefficient was 0.540 (p < 0.05) between the defect score and the pulmonary arterial end-diastolic pressure and -0.616 (p < 0.02) between the defect score and the stroke volume index. There was no significant correlation between the defect score and the cardiac index. 3) There was a linear correlation between the defect score and the LV end-diastolic dimension (r = -0.852, p < 0.001). However, there was no relation between the defect score and the left atrial dimension. When the LV indices were compared between the small (S) and the large (L) defect score group, the L defect group had faster heart rate, larger LV chamber size and the smaller stroke volume index than the S defect group. However, there was no significant difference in the cardiac index between these 2 groups. These results suggest that the LV dilatation in acute or convalescent phase of the first attack of transmural MI is an ominous sign because it was usually accompanied by large infarct size. The present study also indicates that LV dilatation accompanying a large infarct does not satisfactorily compensate for LV dysfunction by Frank-Starling mechanism.

Biphasic thallium 201 SPECT-imaging for the noninvasive diagnosis of myocardial perfusion abnormalities in a child with Kawasaki disease--a case report

International Nuclear Information System (INIS)

Hausdorf, G.; Nienaber, C.A.; Spielman, R.P.

1988-01-01

The mucocutaneous lymph node syndrome (Kawasaki disease) is of increasing importance for the pediatric cardiologist, for coronary aneurysms with the potential of thrombosis and subsequent stenosis can develop in the course of the disease. The authors report a 2 1/2-year-old female child in whom, fourteen months after the acute phase of Kawasaki disease, myocardial infarction occurred. Biphasic thallium 201 SPECT-imaging using dipyridamole depicted anterior wall ischemia and inferolateral infarction. This case demonstrates that noninvasive vasodilation-redistribution thallium 201 SPECT-imaging has the potential to predict reversible myocardial perfusion defects and myocardial necrosis, even in small infants with Kawasaki disease

Morphological aspects of myocardial bridges.

Science.gov (United States)

Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

2013-11-01

Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction.

Directory of Open Access Journals (Sweden)

Tor Biering-Sørensen

Full Text Available Global longitudinal systolic strain (GLS has recently been demonstrated to be a superior prognosticator to conventional echocardiographic measures in patients after myocardial infarction (MI. The aim of this study was to evaluate the prognostic value of regional longitudinal myocardial deformation in comparison to GLS, conventional echocardiography and clinical information.In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI, treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All patients were examined by tissue Doppler imaging (TDI and two-dimensional strain echocardiography (2DSE.During a median-follow-up of 5.3 (IQR 2.5-6.1 years the primary endpoint (death, heart failure or a new MI was reached by 145 (38.9% patients. After adjustment for significant confounders (including conventional echocardiographic parameters and culprit lesion, reduced longitudinal performance in the anterior septal and inferior myocardial regions (but not GLS remained independent predictors of the combined outcome. Furthermore, inferior myocardial longitudinal deformation provided incremental prognostic information to clinical and conventional echocardiographic information (Harrell's c-statistics: 0.63 vs. 0.67, p = 0.032. In addition, impaired longitudinal deformation outside the culprit lesion perfusion region was significantly associated with an adverse outcome (p<0.05 for all deformation parameters.Regional longitudinal myocardial deformation measures, regardless if determined by TDI or 2DSE, are superior prognosticators to GLS. In addition, impaired longitudinal deformation in the inferior myocardial segment provides prognostic information over and above clinical and conventional echocardiographic risk factors. Furthermore, impaired longitudinal deformation outside the culprit lesion perfusion region seems to be a paramount marker of adverse outcome.

Depth and sharpness variations of 410-km and 660-km discontinuities in North China Craton from dense array ambient noise interferometry

Science.gov (United States)

Yao, H.; Feng, J.; Poli, P.; Fang, L.; Wu, Y.

2017-12-01

Recent studies have demonstrated that body waves between pairs of stations can be successfully retrieved from ambient noise cross-correlation at both regional and global scales, although surface waves are the dominant signals. However, it is still difficult to use these retrieved body wave signals to map lateral depth variations of main structural discontinuities or velocity contrasts because of its low signal to noise ratio (SNR). In this research, based on a dense seismic array in eastern North China Craton, reflected P-wave signals from 410-km and 660-km discontinuities can be successfully recovered from ambient noise cross-correlation. To improve SNR of the reflected phases, the cross-correlations are stacked within each bin with the phase-weighted stack (PWS) method. In addition, there exist apparent spatial variations of the relative amplitude ratios between the reflected P410P and P660P phases. The retrieved P410P and P660P phases from stacked correlations reveal lateral variations of both depths and sharpness of the 410-km and 660-km discontinuities along two profiles, which may be related with hot material upwelling and the effect of stagnant Pacific plate in the transition zone beneath North China Craton. The imaging results are generally consistent with the results from teleseismic receiver functions, which demonstrate the possibility of mapping high-resolution topography and sharpness of deep internal discontinuities without earthquake-station geometric limitations. Future joint imaging with both interferometric and passive signals will be better for understanding interface architectures and related dynamic processes of the Earth.

ST segment elevation after myocardial infarction: Viability or ventricular dysfunction? Comparison with myocardial scintigraphy

International Nuclear Information System (INIS)

Chalela, William Azem; Soares, J. Jr.; Meneghetti, J.C.; Olivera, C.G.; Moffa, P.J.; Falcao, A.M.; Ramires, J.A.F.

2004-01-01

The detection of viable myocardium after myocardial infarction is an important indication for revascularization. We compared exercise-induced ST segment elevation with reversibility at Thallium-201 SPECT scintigraphy and regional wall motion assessment by ventriculography. Thirty two patients with previous myocardial infarction and with left ventricular ejection fraction of < 50% were studied. Patients underwent coronary angiography and Thallium-201 SPECT scintigraphy with re-injection protocol before and after coronary artery bypass graft surgery. Group I comprised 11 patients with ST segment elevation during treadmill stress testing. Group II comprised 21 patients without ST segment elevation. Minimal or moderate hypokinesis was present in 2 patients of Group I and in 4 patients of Group II. Nine patients of Group I and 17 patients of Group II had severe hypokinetic, akinetic or dyskinetic myocardium. Scintigraphy revealed reversibility in the myocardial infarction area in 4 patients from Group I (36.4%) and 11 (52.4%) patients from Group II. Improvement in perfusion after coronary artery bypass grafting was observed in 4 patients from Group I and 8 patients from Group II. Sensitivity, specificity, accuracy, and positive and negative predictive values of ST segment elevation were 33.3, 70.6, 55.2, 44.5 and 60% respectively. It was concluded that exercise-induced ST segment elevation after myocardial infarction is present more frequently in cases of severe regional myocardial dysfunction. (author)

Notes on breeding sharp-shinned hawks and Cooper’s hawks in Barnwell County, South Carolina.

Energy Technology Data Exchange (ETDEWEB)

Vukovich, Mark; Kilgo, John, C.

2009-07-01

Abstract - Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooper’s Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned Hawk in Barnwell County, SC and the first report of Sharp-shinned Hawks preying upon Red-headed Woodpeckers. Thirteen of 93 (13.9 %) woodpeckers were killed by accipiters in the summers of 2006 and 2007. Large, contiguous forests managed for Picoides borealis (Red-cockaded Woodpeckers) may be used by breeding Sharp-shinned Hawks. The bright plumage, loud calls, and behavior of Red-headed Woodpeckers, particularly during the nestling stage, may make them conspicuous prey for accipiters.

The expression of myocardial injury in cold induced myocardial imaging and echocardiography of systematic scleroderma

International Nuclear Information System (INIS)

Liang Jiugen; Zhu Xiaojun; Jiang Ningyi; Chen Shaoxiong

1999-01-01

The study was performed with cold-induced 99m Tc(MIBI) myocardial imaging (MI) in 23 patients with systematic scleroderma. The left ventricular function and wall motion were also observed by dimensional echocardiography (UCG). 14 patients had myocardial perfusion abnormalities visualized by MI, including 5 cases with fixed defects of 9 segments, 3 cases with reversible defects of 6 segments and 6 cases with both fixed and reversible one of 14 segments. The positive rate in myocardial imaging had no significant differences between patients with and without Raynaud's phenomenon (0.5>P>0.25). Compared with baseline, the ejection fraction, stroke volume, cardiac output were significantly decreased during cold-induced in patients with abnormal myocardial scintigraphy (P<0.05), and had significant difference compared with normal group (P<0.05). 4 cases with cold-induced reversible perfusion defects had anatomically correlated regional ventricular hypokinesia in UCG

Inference for the Sharpe Ratio Using a Likelihood-Based Approach

Directory of Open Access Journals (Sweden)

Ying Liu

2012-01-01

Full Text Available The Sharpe ratio is the prominent risk-adjusted performance measure used by practitioners. Statistical testing of this ratio using its asymptotic distribution has lagged behind its use. In this paper, highly accurate likelihood analysis is applied for inference on the Sharpe ratio. Both the one- and two-sample problems are considered. The methodology has O(n−3/2 distributional accuracy and can be implemented using any parametric return distribution structure. Simulations are provided to demonstrate the method's superior accuracy over existing methods used for testing in the literature.

Mitochondrial Membrane Permeability Inhibitors in Acute Myocardial Infarction

Directory of Open Access Journals (Sweden)

Cory Trankle, MD

2016-10-01

Full Text Available Despite therapeutic advances, acute myocardial infarction (AMI remains a leading cause of morbidity and mortality worldwide. One potential limitation of the current treatment paradigm is the lack of effective therapies to optimize reperfusion after ischemia and prevent reperfusion-mediated injury. Experimental studies indicate that this process accounts for up to 50% of the final infarct size, lending it importance as a potential target for cardioprotection. However, multiple therapeutic approaches have shown potential in pre-clinical and early phase trials but a paucity of clear clinical benefit when expanded to larger studies. Here we explore this history of trials and errors of the studies of cyclosporine A and other mitochondrial membrane permeability inhibitors, agents that appeared to have a promising pre-clinical record yet provided disappointing results in phase III clinical trials.

Prognostic impact of physical activity prior to myocardial infarction

DEFF Research Database (Denmark)

Ejlersen, Hanne; Andersen, Zorana Jovanovic; von Euler-Chelpin, My Catarina

2017-01-01

the course of myocardial infarction by reducing case fatality and the subsequent risk of heart failure and mortality. Methods: A total of 14,223 participants in the Copenhagen City Heart Study were assessed at baseline in 1976-1978; 1,664 later developed myocardial infarction (mean age at myocardial...... estimated by logistic and Cox proportional hazards regression models, adjusted for age at myocardial infarction and other potential confounders. Results: A total of 425 (25.5%) myocardial infarctions were fatal. Higher levels of LTPA prior to myocardial infarction were associated with lower case fatality...

Dictionary-driven Ischemia Detection from Cardiac Phase-Resolved Myocardial BOLD MRI at Rest

Science.gov (United States)

Bevilacqua, Marco; Dharmakumar, Rohan; Tsaftaris, Sotirios A.

2016-01-01

Cardiac Phase-resolved Blood-Oxygen-Level Dependent (CP–BOLD) MRI provides a unique opportunity to image an ongoing ischemia at rest. However, it requires post-processing to evaluate the extent of ischemia. To address this, here we propose an unsupervised ischemia detection (UID) method which relies on the inherent spatio-temporal correlation between oxygenation and wall motion to formalize a joint learning and detection problem based on dictionary decomposition. Considering input data of a single subject, it treats ischemia as an anomaly and iteratively learns dictionaries to represent only normal observations (corresponding to myocardial territories remote to ischemia). Anomaly detection is based on a modified version of One-class Support Vector Machines (OCSVM) to regulate directly the margins by incorporating the dictionary-based representation errors. A measure of ischemic extent (IE) is estimated, reflecting the relative portion of the myocardium affected by ischemia. For visualization purposes an ischemia likelihood map is created by estimating posterior probabilities from the OCSVM outputs, thus obtaining how likely the classification is correct. UID is evaluated on synthetic data and in a 2D CP–BOLD data set from a canine experimental model emulating acute coronary syndromes. Comparing early ischemic territories identified with UID against infarct territories (after several hours of ischemia), we find that IE, as measured by UID, is highly correlated (Pearson’s r = 0.84) w.r.t. infarct size. When advances in automated registration and segmentation of CP–BOLD images and full coverage 3D acquisitions become available, we hope that this method can enable pixel-level assessment of ischemia with this truly non-invasive imaging technique. PMID:26292338

Assessment of Myocardial Contractile Function Using Global and Segmental Circumferential Strain following Intracoronary Stem Cell Infusion after Myocardial Infarction: MRI Feature Tracking Feasibility Study

International Nuclear Information System (INIS)

Bhatti, Sabha; Al-Khalidi, Hussein; Hor, Kan; Hakeem, Abdul; Taylor, Michael; Quyyumi, Arshed A.; Oshinski, John; Pecora, Andrew L.; Kereiakes, Dean; Chung, Eugene; Pedrizzetti, Gianni; Miszalski-Jamka, Tomasz; Mazur, Wojciech

2012-01-01

Background. Magnetic resonance imaging (MRI) strain analysis is a sensitive method to assess myocardial function. Our objective was to define the feasibility of MRI circumferential strain (ε cc ) analysis in assessing subtle changes in myocardial function following stem cell therapy. Methods and Results. Patients in the Amorcyte Phase I trial were randomly assigned to treatment with either autologous bone-marrow-derived stem cells infused into the infarct-related artery 5 to 11 days following primary PCI or control. MRI studies were obtained at baseline, 3, and 6 months. ε cc was measured in the short axis views at the base, mid and apical slices of the left ventricle (LV) for each patient (13 treatments and 10 controls). Mid-anterior LV ε cc improved between baseline −18.5 ± 8.6 and 3 months −22.6 ± 7.0, P = 0.03. There were no significant changes in ε cc at 3 months and 6 months compared to baseline for other segments. There was excellent intraobserver and interobserver agreement for basal and mid circumferential strain. Conclusion. MRI segmental strain analysis is feasible in assessment of regional myocardial function following cell therapy with excellent intra- and inter-observer variability's. Using this method, a modest interval change in segmental ε cc was detected in treatment group

Imaging techniques for myocardial inflammation

International Nuclear Information System (INIS)

O'Connell, J.B.; Henkin, R.E.; Robinson, J.A.

1986-01-01

Dilated cardiomyopathy (DC) represents a heterogeneous group of disorders which results in morbidity and mortality in young individuals. Recent evidence suggests that a subset of these patients have histologic evidence of myocarditis which is potentially treatable with immunosuppression. The identification of myocardial inflammation may therefore lead to development of therapeutic regimens designed to treat the cause rather than the effect of the myocardial disease. Ultimately, this may result in improvement in the abysmal prognosis of DC. The currently accepted technique for identification of active myocardial inflammation is endomyocardial biopsy. This technique is not perfect, however, since pathologic standards for the diagnosis of myocarditis have not been established. Furthermore, focal inflammation may give rise to sampling error. The inflammation-avid radioisotope gallium-67 citrate has been used as an adjunct to biopsy improving the yield of myocarditis from 7 percent to 36 percent. Serial imaging correlates well to biopsy results. Future studies are designed to study the applicability of lymphocyte labelling techniques to myocardial inflammatory disease

Prediction of left ventricular functional recovery in patients with acute myocardial infarction using single photon emission computed tomography with thallium-201 and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid

International Nuclear Information System (INIS)

Hashimoto, Akiyoshi; Nakata, Tomoaki; Nagao, Kazuhiko

1995-01-01

The relationships between myocardial perfusion, fatty acid metabolism, and cardiac function were investigated using dual single photon emission computed tomography (SPECT) with thallium and iodine-123-β-methyl-p-iodophenyl-pentadecanoic acid ( 123 I-BMIPP) during the acute ( 10±1 days) and recovery (60±14 days) phases in 29 patients with acute myocardial infarction. There were 18 patients who underwent successful primary coronary angioplasty (PTCA group) and 11 patients who received conservative therapy (non PTCA group). Thallium and BMIPP uptakes were scored visually by a 4-point system and left ventricular ejection fraction (LVEF) was calculated by radionuclide ventriculography. Although significant positive correlations between thallium and 123 I-BMIPP scores were observed during both phases, BMIPP scores were significantly lower than thallium scores in both acute and recovery phases in the PTCA group. No significant difference in thallium and 123 I-BMIPP scores was observed at the recovery phase in the non PTCA group. LVEF significantly correlated with thallium and 123 I-BMIPP scores in both phases in the PTCA group. Furthermore, the difference between thallium and 123 I-BMIPP scores during the acute phase significantly correlated with the improvement of LVEF during the follow-up period in the PTCA group (y=0.92x-0.77, r=0.65, p 123 I-BMIPP SPECT is increased by reperfusion therapy and persists at least until the recovery phase of myocardial infarction. The recovery of left ventricular function depends on the extent of the mismatched uptake, indicating a predictor for functional recovery following acute myocardial infarction. (author)

Energy dissipation characteristics of sharp-edged orifice plate

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Ai Wanzheng

2015-08-01

Full Text Available The energy loss coefficient, relating directly to the energy dissipation ratio, is an important index of this energy dissipater. In this article, this coefficient and its affecting parameters were analyzed by theoretical considerations, and their relationships were obtained by numerical simulations. It could be concluded that the energy loss coefficient of sharp-edged orifice plate and its backflow region length were mainly dominated by the contraction ratio of the orifice plate. Sharp-edged orifice plate’s energy loss coefficient and its backflow region length all increase slightly with the increase in its thickness. When Reynolds number is in the range of 9.00×104–10.3×106, Reynolds number has little impacts on energy loss coefficient and backflow region length. Two empirical expressions, relating to backflow region length and energy loss coefficient, respectively, were presented.

Cryogenic receiver front-end with sharp skirt characteristics

Energy Technology Data Exchange (ETDEWEB)

Narahashi, S [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Satoh, K [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Kawai, K [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Koizumi, D [RF Technology Laboratory, Wireless Laboratories, NTT DoCoMo, Inc, Yokosuka, Kanagawa 239-8536 (Japan); Nojima, T [Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido 060-0808 (Japan)

2006-05-15

This paper presents an experimental cryogenic receiver front-end (CRFE) with sharp skirt characteristics for mobile base stations. The CRFE comprises a high-temperature superconducting filter, a cryogenic low-noise amplifier, and a highly reliable cryostat that is very compact. The major characteristics of the proposed CRFE measured at 70 K are a centre frequency of 1.95 GHz, passband width of 20 MHz, sharp selectivity of 20 dB/100 kHz, 1.4 dB ripple, 31.3 dB average passband gain, and average passband equivalent noise temperature of 47.9 K. The CRFE weighs 19 kg and occupies 35 l. Random failure of the cryostat is also evaluated by a continuous operation test using four identical ones simultaneously. The cryostat used in the CRFE has a high reliability level of over five years of continuous maintenance-free operation.

Quantitative aspects of myocardial perfusion imaging

International Nuclear Information System (INIS)

Vogel, R.A.

1980-01-01

Myocardial perfusion measurements have traditionally been performed in a quantitative fashion using application of the Sapirstein, Fick, Kety-Schmidt, or compartmental analysis principles. Although global myocardial blood flow measurements have not proven clinically useful, regional determinations have substantially advanced our understanding of and ability to detect myocardial ischemia. With the introduction of thallium-201, such studies have become widely available, although these have generally undergone qualitative evaluation. Using computer-digitized data, several methods for the quantification of myocardial perfusion images have been introduced. These include orthogonal and polar coordinate systems and anatomically oriented region of interest segmentation. Statistical ranges of normal and time-activity analyses have been applied to these data, resulting in objective and reproducible means of data evaluation

Sharp bounds for periodic solutions of Lipschitzian differential equations

International Nuclear Information System (INIS)

Zevin, A A

2009-01-01

A general system of Lipschitzian differential equations, containing simultaneously terms without delay and with arbitrary constant and time-varying delays, is considered. For the autonomous case, a lower bound for the period of nonconstant periodic solutions, expressed in the respective supremum Lipschitz constants, is found. For nonautonomous periodic equations, explicit upper bounds for the amplitudes and maximum derivatives of periodic solutions are obtained. For all n ≥ 2, the bounds do not depend on n and, in general, are different from that for n = 1. All the bounds are sharp; they are attained in linear differential equations with piece-wise constant deviating arguments. A relation between the obtained bounds and the sharp bounds in other metrics is established

Exploring Moho sharpness in Northeastern North China Craton with frequency-dependence analysis of Ps receiver function

Science.gov (United States)

Zhang, P.; Yao, H.; Chen, L.; WANG, X.; Fang, L.

2017-12-01

The North China Craton (NCC), one of the oldest cratons in the world, has attracted wide attention in Earth Science for decades because of the unusual Mesozoic destruction of its cratonic lithosphere. Understanding the deep processes and mechanism of this craton destruction demands detailed knowledge about the deep structure of this region. In this study, we calculate P-wave receiver functions (RFs) with two-year teleseismic records from the North China Seismic Array ( 200 stations) deployed in the northeastern NCC. We observe both diffused and concentered PpPs signals from the Moho in RF waveforms, which indicates heterogeneous Moho sharpness variations in the study region. Synthetic Ps phases generated from broad positive velocity gradients at the depth of the Moho (referred as Pms) show a clear frequency dependence nature, which in turn is required to constrain the sharpness of the velocity gradient. Practically, characterizing such a frequency dependence feature in real data is challenging, because of low signal-to-noise ratio, contaminations by multiples generated from shallow structure, distorted signal stacking especially in double-peak Pms signals, etc. We attempt to address these issues by, firstly, utilizing a high-resolution Moho depth model of this region to predict theoretical delay times of Pms that facilitate more accurate Pms identifications. The Moho depth model is derived by wave-equation based poststack depth migration on both Ps phase and surface-reflected multiples in RFs in our previous study (Zhang et al., submitted to JGR). Second, we select data from a major back azimuth range of 100° - 220° that includes 70% teleseismic events due to the uneven data coverage and to avoid azimuthal influence as well. Finally, we apply an adaptive cross-correlation stacking of Pms signals in RFs for each station within different frequency bands. High-quality Pms signals at different frequencies will be selected after careful visual inspection and adaptive

Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

International Nuclear Information System (INIS)

Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem

2004-01-01

It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of 201 Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of 201 Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium bicarbonate augmentation may have significant implications for stress-thallium scintigraphy

Nitrogen-13-labeled ammonia for myocardial imaging

Energy Technology Data Exchange (ETDEWEB)

Walsh, W.F.; Fill, H.R.; Harper, P.V.

1977-01-01

Cyclotron-produced nitrogen-13 (half-life 10 min), as labeled ammonia (/sup 13/NH/sub 4//sup +/), has been evaluated as a myocardial perfusion imaging agent. The regional myocardial uptake of /sup 13/NH/sub 4//sup +/ has been shown to be proportional to regional tissue perfusion in animal studies. Intravenously administered /sup 13/NH/sub 4//sup +/ is rapidly cleared from the circulation, being extracted by the liver (15 percent), lungs, myocardium (2 percent--4 percent), brain, kidney, and bladder. Myocardial ammonia is metabolized mainly to glutamine via the glutamine synthetase pathway. Pulmonary uptake is substantial, but usually transient, except in smokers where clearance may be delayed. The positron annihilation irradiation (511 keV) of /sup 13/N may be imaged with a scintillation camera, using either a specially designed tungsten collimator or a pinhole collimator. After early technical problems with collimation and the production method of /sup 13/NH/sub 4//sup +/ were overcome, reproducible high quality myocardial images were consistently obtained. The normal myocardial image was established to be of a homogeneous ''doughnut'' configuration. Imaging studies performed in patients with varying manifestations of ischemic and valvular heart disease showed a high incidence of localized perfusion defects, especially in patients with acute myocardial infarction. Sequential studies at short intervals in patients with acute infarction showed correlation between alterations in regional perfusion and the clinical course of the patient. It is concluded that myocardial imaging with /sup 13/NH/sub 4//sup +/ and a scintillation camera provides a valid and noninvasive means of assessing regional myocardial perfusion. This method is especially suitable for sequential studies of acute cardiac patients at short intervals. Coincidence imaging of the 511 keV annihilation irradiation provides a tomographic and potentially quantitative assessment of the

Mechanisms of sharp wave initiation and ripple generation.

Science.gov (United States)

Schlingloff, Dániel; Káli, Szabolcs; Freund, Tamás F; Hájos, Norbert; Gulyás, Attila I

2014-08-20

Replay of neuronal activity during hippocampal sharp wave-ripples (SWRs) is essential in memory formation. To understand the mechanisms underlying the initiation of irregularly occurring SWRs and the generation of periodic ripples, we selectively manipulated different components of the CA3 network in mouse hippocampal slices. We recorded EPSCs and IPSCs to examine the buildup of neuronal activity preceding SWRs and analyzed the distribution of time intervals between subsequent SWR events. Our results suggest that SWRs are initiated through a combined refractory and stochastic mechanism. SWRs initiate when firing in a set of spontaneously active pyramidal cells triggers a gradual, exponential buildup of activity in the recurrent CA3 network. We showed that this tonic excitatory envelope drives reciprocally connected parvalbumin-positive basket cells, which start ripple-frequency spiking that is phase-locked through reciprocal inhibition. The synchronized GABA(A) receptor-mediated currents give rise to a major component of the ripple-frequency oscillation in the local field potential and organize the phase-locked spiking of pyramidal cells. Optogenetic stimulation of parvalbumin-positive cells evoked full SWRs and EPSC sequences in pyramidal cells. Even with excitation blocked, tonic driving of parvalbumin-positive cells evoked ripple oscillations. Conversely, optogenetic silencing of parvalbumin-positive cells interrupted the SWRs or inhibited their occurrence. Local drug applications and modeling experiments confirmed that the activity of parvalbumin-positive perisomatic inhibitory neurons is both necessary and sufficient for ripple-frequency current and rhythm generation. These interneurons are thus essential in organizing pyramidal cell activity not only during gamma oscillation, but, in a different configuration, during SWRs. Copyright © 2014 the authors 0270-6474/14/3411385-14$15.00/0.

Effect of eating on thallium myocardial imaging

International Nuclear Information System (INIS)

Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

1986-01-01

To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The 201 Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of 201 Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed 201 Tl images causes increased 201 Tl myocardial clearance rates and may alter 201 Tl myocardial redistribution over time

Gadolinium-DTPA-enhanced magnetic resonance imaging and functional outcome in patients with acute myocardial infarction

International Nuclear Information System (INIS)

Kitamura, Jun; Shimada, Toshio; Murakami, Yo; Ochiai, Koichi; Inoue, Shin-ichi; Ishibashi, Yutaka; Kinoshita, Yoshihisa; Sano, Kazuya; Murakami, Rinji

1999-01-01

This study was designed to test the hypothesis that Gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)-enhanced magnetic resonance images (MRI) reflect the severity of ischemic injury during the acute and chronic phases of myocardial infarction (MI). Twenty-nine patients with their first acute MI underwent Gd-DTPA-enhanced MRI in the first week (4.2±0.3 days) and at 1 month after onset. Pairs of left ventriculograms were compared with Gd-DTPA-enhanced magnetic resonance images, classified into 3 pattern groups: hyper-enhancement, with and without a central hypo-enhanced region (P1 and P2, respectively), and non-enhancement (P3). In the acute phase of MI, P1 was found in 10, P2 in 11, and P3 in 8 patients. One month later, the image pattern had changed from P1 to P2 in a single patient, from P2 to P3 in 4 patients, and had remained identical in the others. Patients with P3 showed improvement of anterior wall motion in the 1-month follow-up study, and had higher TIMI flow grades and lower peak creatine kinase values than those without recovery. Thus, Gd-DTPA-enhanced magnetic resonance images, closely reflecting the severity of myocardial injury, are useful in predicting myocardial functional recovery after MI. (author)

Relationship between sharps disposal containers and Clostridium difficile infections in acute care hospitals.

Science.gov (United States)

Pogorzelska-Maziarz, Monika

2015-10-01

Sharps disposal containers are ubiquitous in health care facilities; however, there is paucity of data on their potential role in pathogen transmission. This study assessed the relationship between use of single-use versus reusable sharps containers and rates of Clostridium difficile infections in a national sample of hospitals. A 2013 survey of 1,990 hospitals collected data on the use of sharps containers. Responses were linked to the 2012 Medicare Provider Analysis and Review dataset. Bivariate and multivariable negative binomial regression were conducted to examine differences in C difficile rates between hospitals using single-use versus reusable containers. There were 604 hospitals who completed the survey; of these, 539 provided data on use of sharps containers in 2012 (27% response rate). Hospitals had, on average, 289 beds (SD ± 203) and were predominantly non-for-profit (67%) and nonteaching (63%). Most used reusable sharps containers (72%). In bivariate regression, hospitals using single-use containers had significantly lower rates of C difficile versus hospitals using reusable containers (incidence rate ratio [IRR] = 0.846, P = .001). This relationship persisted in multivariable regression (IRR = 0.870, P = .003) after controlling for other hospital characteristics. This is the first study to show a link between use of single-use sharps containers and lower C difficile rates. Future research should investigate the potential for environmental contamination of reusable containers and the role they may play in pathogen transmission. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Estimation of regional myocardial sympathetic neuronal function with I-123 metaiodobenzylguanidine (MIBG) myocardial images in patients with cardiomyopathy

International Nuclear Information System (INIS)

Tanaka, Takeshi; Aizawa, Tadanori; Kato, Kazuzo; Nakano, Hajime; Igarashi, Masaki; Ueno, Takashi; Hirosawa, Koshichiro; Kusakabe, Kiyoko.

1989-01-01

Myocardial SPECT images with I-123 metaiodobenzylguanidine (MIBG) were obtained in 10 patients with cardiomyopathy under stable state. For myocardial imaging, MIBG and Tl-201 (Tl) were simultaneously injected and collected. The ratio of MIBG to Tl (M/T ratio) in ROI was obtained with 50% cut off levels in order to eliminate background activity. The patients were divided into three major groups: (l) those who had the M/T ratio ranging from 0.8 to l.20 at rest and had marked defects in the infero-lateral region on delayed MIBG images, where pathophysiologically accelerated regional sympathetic neuronal function was suspected (n=5), (II) those who had increased M/T ratios (l.6 and l.7) in the basal septal wall (n=3), and (III) those who had decreased M/T ratios (0.7 and 0.75) in the apical septal wall, where depletion of myocardial norepinephrine was suspected (n=2). These findings indicate the potential of myocardial MIBG images to evaluate myocardial distribution of norepinephrine, i.e. myocardial sympathetic neuronal function. Certain shortcomings, such as an increased background due to dual isotopes and an increased pulmonary uptake of MIBG, require further study on quantitative methods. (Namekawa, K)

Comparison with myocardial perfusion MRI and myocardial perfusion SPECT in the diagnostic performance of coronary artery disease. A meta-analysis

International Nuclear Information System (INIS)

Iwata, Kunihiro; Kubota, Makoto; Ogasawara, Katsuhiko

2008-01-01

We compared the diagnostic abilities of stress myocardial perfusion MRI (myocardial perfusion MRI) and myocardial perfusion single photon emission computed tomography (SPECT), using a meta-analysis method. We investigated the diagnostic abilities of MRI and SPECT in similar subject groups in reports written in English or Japanese. The reports to be used for analysis were selected according to a ''screening standard,'' which was established in advance. After consolidating the data from the selected reports, we compared the integrated odds ratio, the point estimation values of sensibility/specificity, and the summary receiver operating characteristic (ROC) curve. For the analysis, six reports were selected (subjects: 153, coronary-artery target sites: 447). Meta-analysis revealed that the diagnostic ability of myocardial perfusion MRI was superior to that of myocardial perfusion SPECT regarding each of the parameters. This is considered to be supportive evidence of the usefulness of myocardial perfusion MRI. (author)

Sharp Injuries Among Hospital Waste Handlers | Olaitan | Nigerian ...

African Journals Online (AJOL)

, C as well as other before commencing on their jobs. Workers should be screened for infective diseases that can be of legal problem while at the job and the workers should be effectively immunized. Key words: sharp injuries, waste, handlers, ...

Notes on breeding sharp-shinned hawks and cooper’s hawks in Barnwell County, South Carolina

Science.gov (United States)

Mark Vukovich; John C. Kilgo

2009-01-01

Breeding records of Accipiter striatus (Sharp-shinned Hawks) in the southeastern US are scattered and isolated. We documented a Sharp-shinned Hawk and Accipiter cooperii (Cooper’s Hawk) nest while conducting a telemetry study on Melanerpes erythrocephalus (Red-headed Woodpeckers) in Barnwell County, SC in 2006 and 2007. We report the first known nest of a Sharp-shinned...

Myocardial Blood Volume Is Associated with Myocardial Oxygen Consumption: An Experimental Study with CMR in a Canine Model

Science.gov (United States)

McCommis, Kyle S.; Zhang, Haosen; Goldstein, Thomas A.; Misselwitz, Bernd; Abendschein, Dana R.; Gropler, Robert J.; Zheng, Jie

2009-01-01

OBJECTIVES To evaluate the feasibility of cardiovascular MR (CMR) to determine regional myocardial perfusion and O2 metabolism, and assess the role of myocardial blood volume (MBV) on oxygen supply. BACKGROUND Coronary artery disease presents as an imbalance of myocardial oxygen supply and demand. We have developed relevant CMR methods to determine the relationship of myocardial blood flow (MBF) and MBV to oxygen consumption (MVO2) during pharmacologic hyperemia. METHODS Twenty-one mongrel dogs were studied with varying stenosis severities imposed on the proximal left anterior descending (LAD) coronary artery. MBF and MBV were determined by CMR first-pass perfusion, while the oxygen extraction fraction (OEF) and MVO2 were determined by the myocardial Blood-Oxygen-Level-Dependent (BOLD) effect and Fick’s law, respectively. MR imaging was performed at rest, and during either dipyridamole-induced vasodilation or dobutamine-induced hyperemia. Regional differences in myocardial perfusion and oxygenation were then evaluated. RESULTS Dipyridamole and dobutamine both led to 145–200% increases in MBF and 50–80% increases in MBV in normal perfused myocardium. As expected, MVO2 increased more significantly with dobutamine (~175%) than dipyridamole (~40%). Coronary stenosis resulted in an attenuation of MBF, MBV, and MVO2 in both the LAD-subtended stenosis region and the left circumflex subtended remote region. Liner regression analysis showed that MBV reserve appears to be more correlated with MVO2 reserve during dobutamine stress than MBF reserve, particularly in the stenotic regions. Conversely, MBF reserve appears to be more correlated with MVO2 reserve during dipyridamole, although neither of these differences was significant. CONCLUSIONS Noninvasive evaluation of both myocardial perfusion and oxygenation by CMR facilitates direct monitoring of regional myocardial ischemia and provides a valuable tool for better understanding microvascular pathophysiology. These

delta-Opioid-induced pharmacologic myocardial hibernation during cardiopulmonary resuscitation.

Science.gov (United States)

Fang, Xiangshao; Tang, Wanchun; Sun, Shijie; Weil, Max Harry

2006-12-01

Cardiac arrest and cardiopulmonary resuscitation is an event of global myocardial ischemia and reperfusion, which is associated with severe postresuscitation myocardial dysfunction and fatal outcome. Evidence has demonstrated that mammalian hibernation is triggered by cyclic variation of a delta-opiate-like compound in endogenous serum, during which the myocardial metabolism is dramatically reduced and the myocardium tolerates the stress of ischemia and reperfusion without overt ischemic and reperfusion injury. Previous investigations also proved that the delta-opioid agonist elicited the cardioprotection in a model of regional ischemic intact heart or myocyte. Accordingly, we were prompted to search for an alternative intervention of pharmacologically induced myocardial hibernation that would result in rapid reductions of myocardial metabolism and therefore minimize the myocardial ischemic and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation. Prospective, controlled laboratory study. University-affiliated research laboratory. In the series of studies performed in the established rat and pig model of cardiac arrest and cardiopulmonary resuscitation, the delta-opioid receptor agonist, pentazocine, was administered during ventricular fibrillation. : The myocardial metabolism reflected by the concentration of lactate, or myocardial tissue PCO2 and PO2, is dramatically reduced during cardiac arrest and cardiopulmonary resuscitation. These are associated with less severe postresuscitation myocardial dysfunction and longer duration of postresuscitation survival. delta-Opioid-induced pharmacologic myocardial hibernation is an option to minimize the myocardial ischemia and reperfusion injury during cardiac arrest and cardiopulmonary resuscitation.

Sgarbossa criteria and acute myocardial infarction.

Science.gov (United States)

Alang, Neha; Bathina, Jaya; Kranis, Mark; Angelis, Dimitrios

2010-01-01

Diagnosis of acute ST-elevation myocardial infarction in the presence of left bundle branch block is difficult. present a case of acute myocardial infarction with LBBB diagnosed and treated using the Sgarbossa criteria.

Changes of blood and myocardial tissue contents of IGF-I after development of acute myocardial infarction in rat models

International Nuclear Information System (INIS)

Cao Heng; Wei Youquan

2006-01-01

Objective: To study the changes of IGF-I contents in blood and myocardium after experimental acute myocardial infarction in rat models. Methods: Rat models of acute myocardial infarction were prepared with intraperitoneal injection of isoproterenol. Eight models were sacrificed 48h later and another 8 models were sacrificed 14 days after preparation. Serum and myocardium homogenate contents of IGF-I were measured with RIA in these models as well as 8 control rats. Results: The serum and myocardial contents of IGF-I increased in the models sacrificed at 48h, but were not significantly higher than those in the controls (P>0.05). At 14 th day, the levels were significantly higher than those in controls and at 48h (both P<0.05). The serum and myocardial contents of IGF-I were mutually correlated in the controls and 14 day models (r=0.9987, r=0.9992; P<0.01). Conclusion After myocardial infarction, the serum and myocardial IGF-I contents increased along with the course of disease in the rat models. (authors)

Myocardial perfusion imaging with dual energy CT

Energy Technology Data Exchange (ETDEWEB)

Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

2016-10-15

Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

Reversible myocardial ischaemia or irreversible myocardial fibrosis

International Nuclear Information System (INIS)

Mathey, D.; Hanrath, P.; Kupper, W.; Bleifeld, W.; Montz, R.; Knop, J.; Stritzke, P.; Kroeger, E.; Bleese, N.

1978-01-01

The results of biphasis 201 thallium ( 201 Tl) scanning were compared with those of coronary arteriography, left ventricular angiography and stress ECG in 56 patients with coronary artery disease and six with no evidence of heart disease. There were 104 201 Tl defects, 50 of them reversible. The defects were always located in the area supplied by a critically stenotic coronary artery. Correlation of regional wall motion with 201 Tl activity demonstrated that in all forms of abnormal wall motion there was either ischaemia or fibrosis. The resting LV angiogram thus does not make it possible to distinguish between myocardial ischaemia and fibrosis. Taking the LV angiogram as a standard, the rate of false-positive 201 Tl scintigrams was 5%, that of false-negative ones 23%. The biphasic 201 Tl scintigram was more sensitive than the stress ECG in detecting myocardial ischaemia. It furthermore made it possible to localize the ischaemic (or fibrotic) region within the LV and to estimate its size. (orig.) [de

Influence of gantry angle in helical computed tomography. Usefullness of 1-dimension sharpness filter

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Kawano, Hirofumi; Suzuki, Toru; Matsuura, Shigeru; Kai, Tsuyoshi; Shimizu, Toshiyuki [Hyuga Hospital of Saiseikai Foundation, Kadogawa, Miyazaki (Japan)

2001-05-01

When we let gantry tilt and do scan in helical CT, vertical sharpness deteriorates. We were able to revise it with 1-dimensional sharpness filter which the square sum of difference of MTF was compared, and was designed this time. And the unsharpness was in proportion to sin of gantry angle. As a result, we led several sets of frequency emphasis degree. There is a model to built 1-dimension sharpness filter in a scan plan. It is useful for clinical diagnoses. (author)

Influence of gantry angle in helical computed tomography. Usefullness of 1-dimension sharpness filter

International Nuclear Information System (INIS)

Kawano, Hirofumi; Suzuki, Toru; Matsuura, Shigeru; Kai, Tsuyoshi; Shimizu, Toshiyuki

2001-01-01

When we let gantry tilt and do scan in helical CT, vertical sharpness deteriorates. We were able to revise it with 1-dimensional sharpness filter which the square sum of difference of MTF was compared, and was designed this time. And the unsharpness was in proportion to sin of gantry angle. As a result, we led several sets of frequency emphasis degree. There is a model to built 1-dimension sharpness filter in a scan plan. It is useful for clinical diagnoses. (author)

Assessment of Takotsubo (ampulla) cardiomyopathy using 99mTc-tetrofosmin myocardial SPECT. Comparison with acute coronary syndrome

International Nuclear Information System (INIS)

Ito, Kazuki; Katoh, Shuji

2003-01-01

We assessed Takotsubo (ampulla) cardiomyopathy compared with acute coronary syndrome (ACS) using two-dimensional echocardiography and 99m Tc-tetrofosmin myocardial SPECT. We examined 10 patients with Takotsubo cardiomyopathy and 16 with ACS at the time of emergency admission (acute phase), at three to nine days after the attack (subacute phase) and at one month after the attack (chronic phase). The left ventricle was divided into nine regions on echocardiograms and SPECT images, and the degree of abnormalities in each region was scored in five grades from normal (0) to severely abnormal (4). Coronary angiography revealed total or subtotal occlusion in patients with ACS but no stenotic legions in those with Takotsubo cardiomyopathy. The amount of ST segment elevation (mm) was 7.9±3.4 in patients with Takotsubo cardiomyopathy and 7.3±3.7 in those with ACS (N.S.). Abnormal wall motion scores on echocardiograms were 13.8±4.4, 4.4±3.8 and 1.8±2.3 during the acute, subacute and chronic phases in patients with Takotsubo cardiomyopathy, and 13.9±4.0, 11.7±3.7, 7.6±4.2, respectively in patients with ACS. The value of MB fraction of creatine phosphokinase (IU/l) was 34±23 in patients with Takotsubo cardiomyopathy and 326±98 in those with ACS (p 99m Tc-tetrofosmin myocardial SPECT were 11.4±3.2, 3.2±3.3 and 0.7±1.1 during the acute, subacute and chronic phases respectively, in patients with Takotsubo cardiomyopathy, and 15.8±4.1, 13.5±4.4, 8.2±4.4, respectively, in those with ACS. The numbers of myocardial segments that did not uptake 99m Tc-tetrofosmin during the acute phase were 0.5±0.8 and 3.6±2.8 in patients with Takotsubo cardiomyopathy and ACS, respectively. Impaired coronary microcirculation might be a causative mechanism of Takotsubo cardiomyopathy. (author)

Quantitative Myocardial Perfusion Imaging Versus Visual Analysis in Diagnosing Myocardial Ischemia: A CE-MARC Substudy.

Science.gov (United States)

Biglands, John D; Ibraheem, Montasir; Magee, Derek R; Radjenovic, Aleksandra; Plein, Sven; Greenwood, John P

2018-05-01

This study sought to compare the diagnostic accuracy of visual and quantitative analyses of myocardial perfusion cardiovascular magnetic resonance against a reference standard of quantitative coronary angiography. Visual analysis of perfusion cardiovascular magnetic resonance studies for assessing myocardial perfusion has been shown to have high diagnostic accuracy for coronary artery disease. However, only a few small studies have assessed the diagnostic accuracy of quantitative myocardial perfusion. This retrospective study included 128 patients randomly selected from the CE-MARC (Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease) study population such that the distribution of risk factors and disease status was proportionate to the full population. Visual analysis results of cardiovascular magnetic resonance perfusion images, by consensus of 2 expert readers, were taken from the original study reports. Quantitative myocardial blood flow estimates were obtained using Fermi-constrained deconvolution. The reference standard for myocardial ischemia was a quantitative coronary x-ray angiogram stenosis severity of ≥70% diameter in any coronary artery of >2 mm diameter, or ≥50% in the left main stem. Diagnostic performance was calculated using receiver-operating characteristic curve analysis. The area under the curve for visual analysis was 0.88 (95% confidence interval: 0.81 to 0.95) with a sensitivity of 81.0% (95% confidence interval: 69.1% to 92.8%) and specificity of 86.0% (95% confidence interval: 78.7% to 93.4%). For quantitative stress myocardial blood flow the area under the curve was 0.89 (95% confidence interval: 0.83 to 0.96) with a sensitivity of 87.5% (95% confidence interval: 77.3% to 97.7%) and specificity of 84.5% (95% confidence interval: 76.8% to 92.3%). There was no statistically significant difference between the diagnostic performance of quantitative and visual analyses (p = 0.72). Incorporating rest myocardial

Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

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Arabi, Mohammad, E-mail: marabi2004@hotmail.com; Ahmed, Ishtiaq; Mat’hami, Abdulaziz [Prince Sultan Military Medical City (PSMMC), Division of Endovascular Interventional Radiology, Department of Medical Imaging (Saudi Arabia); Ahmed, Dildar; Aslam, Naveed [Prince Sultan Military Medical City (PSMMC), Department of Nephrology (Saudi Arabia)

2016-06-15

PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

Sharp Central Venous Recanalization in Hemodialysis Patients: A Single-Institution Experience

International Nuclear Information System (INIS)

Arabi, Mohammad; Ahmed, Ishtiaq; Mat’hami, Abdulaziz; Ahmed, Dildar; Aslam, Naveed

2016-01-01

PurposeWe report our institutional experience with sharp central venous recanalization in chronic hemodialysis patients who failed standard techniques.Materials and MethodsSince January 2014, a series of seven consecutive patients (four males and three females), mean age 35 years (18–65 years), underwent sharp central venous recanalization. Indications included obtaining hemodialysis access (n = 6) and restoration of superior vena cava (SVC) patency to alleviate occlusion symptoms and restore fistula function (n = 1). The transseptal needle was used for sharp recanalization in six patients, while it could not be introduced in one patient due to total occlusion of the inferior vena cava. Instead, transmediastinal SVC access using Chiba needle was obtained.ResultsTechnical success was achieved in all cases. SVC recanalization achieved symptoms’ relief and restored fistula function in the symptomatic patient. One patient underwent arteriovenous fistula creation on the recanalized side 3 months after the procedure. The remaining catheters were functional at median follow-up time of 9 months (1–14 months). Two major complications occurred including a right hemothorax and a small hemopericardium, which were managed by covered stent placement across the perforated SVC.ConclusionSharp central venous recanalization using the transseptal needle is feasible technique in patients who failed standard recanalization procedures. The potential high risk of complications necessitates thorough awareness of anatomy and proper technical preparedness.

MRS algorithm: a new method for searching myocardial region in SPECT myocardial perfusion images.

Science.gov (United States)

He, Yuan-Lie; Tian, Lian-Fang; Chen, Ping; Li, Bin; Mao, Zhong-Yuan

2005-10-01

First, the necessity of automatically segmenting myocardium from myocardial SPECT image is discussed in Section 1. To eliminate the influence of the background, the optimal threshold segmentation method modified for the MRS algorithm is explained in Section 2. Then, the image erosion structure is applied to identify the myocardium region and the liver region. The contour tracing method is introduced to extract the myocardial contour. To locate the centriod of the myocardium, the myocardial centriod searching method is developed. The protocol of the MRS algorithm is summarized in Section 6. The performance of the MRS algorithm is investigated and the conclusion is drawn in Section 7. Finally, the importance of the MRS algorithm and the improvement of the MRS algorithm are discussed.

Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

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Tamura, Takuhisa; Shibuya, Noritoshi (Kawatana National Hospital, Nagasaki (Japan)); Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke

1993-01-01

Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD[>=]10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD[>=]10 and age[>=]15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age[>=]15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author).

Myocardial infarction, androgen and the skin.

Science.gov (United States)

Halim, M M; Meyrick, G; Jeans, W D; Murphy, D; Burton, J L

1978-01-01

Various indices of masculinity were compared in 48 men who had recovered from myocardial infarction and in their age-matched controls. We found little evidence to support the idea that myocardial infarction is related to increased androgenic stimulation. The patients with myocardial infarction had no increase in plasma testosterone, muscle thickness, sebum excretion rate, maximal sweat secretion rate, male pattern alopecia or density of terminal body hair, but as a group they had a slight increase in skin and bone thickness compared with the controls.

Usefulness of rest-redistribution on thallium myocardial scintigraphy in patients with acute myocardial infarction by SPECT; Analysis by bull's eye and unfolded map images

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Tahara, Yorio; Taya, Makoto; Sasaki, Akira; Nishimura, Tooru; Shimoyama, Katsuya; Mizuno, Haruyoshi; Ono, Akifumi; Okada, Michio; Ishikawa, Kyozo (Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine)

1990-01-01

The purpose of this study was to clarify the clinical significance of rest-redistribution in myocardial scintigraphy (SPECT) in acute myocardial infarction (AMI). 30 patients with AMI within one week after the onset of attack were studied. SPECT images were obtained 10 min and 3hrs after injection of {sup 201}Tl. Bull's eye images and unfolded map images were prepared. A {sup 201}Tl uptake was studied at the infarct and non-infarct sites. Exercise SPECT and radionuclide angiography were performed in all patients one month after the onset of AMI, and the findings were compared with clinical and coronary angiographic (CAG) findings. Redistribution of Tl at rest was observed at the infarct sites in 9 of the 30 patients. Redistribution at rest was observed at the non-infarct sites in 8 patients. Redistribution at rest was observed during exercise SPECT one month after the onset of AMI in patients with redistribution at rest in the acute phase. In patients with redistribution at rest at the infarct site, left ventricular ejection fraction (EF) improved one month after the onset of AMI ({Delta}EF>5%), but it decreased slightly during exercise. Wall motion at the infarct site was not much impaired in patients who showed redistribution at rest at the infarct site. Angina pectoris and recurrence of myocardial infarction were observed more frequently on SPECT, but no characteristic findings were obtained on CAG in those with redistribution at rest. In conclusion, cardiac function and wall motion at the infarct site are better preserved in patients with redistribution of Tl at rest on SPECT in the acute stage of myocardial infarction, as compared with patients having fixed defects, but the EF decrease slightly during exercise and the frequency of post-infarction angina is greater in those patients. Resting SPECT in AMI is considered to provide useful information for predicting cardiac function and the clinical course following myocardial infarction. (author).

Myocardial thallium-201 kinetics in normal and ischemic myocardium

International Nuclear Information System (INIS)

Grunwald, A.M.; Watson, D.D.; Holzgrefe, H.H. Jr.; Irving, J.F.; Beller, G.A.

1981-01-01

The net myocardial accumulation of thallium-201 after injection depends upon the net balance between continuing myocardial extraction from low levels of recirculating thallium in the blood compartment and the net rate of efflux of thallium from the myocardium into the extracardiac blood pool. These experiments were designed to measure separately the myocardial extraction and intrinsic myocardial efflux of thallium-201 at normal and at reduced rates of myocardial blood flow. The average myocardial extraction fraction at normal blood flow in 10 anesthetized dogs was 82 +/- 6% (+/- SD) at normal coronary arterial perfusion pressures and increased insignificantly, to 85 +/- 7%, at coronary perfusion pressures of 10--35 mm Hg. At normal coronary arterial perfusion pressures in 12 additional dogs, the intrinsic thallium washout in the absence of systemic recirculation had a half-time (T 1/2) of 54 +/- 7 minutes. The intrinsic cellular washout rate began to increase as distal perfusion pressures fell below 60 mm Hg and increased markedly to a T 1/2 of 300 minutes at perfusion pressures of 25--30 mm Hg. A second, more rapid component of intrinsic thallium washout (T 1/2 2.5 minutes) representing approximately 7% of the total initially extracted myocardial thallium was observed. The faster washout component is presumed to be due to washout of interstitial thallium unextracted by myocardial cells, whereas the slower component is presumed due to intracellular washout. The net clearance time of thallium measured after i.v. injection is much longer than the intrinsic myocardial cellular washout rate because of continuous replacement of myocardial thallium from systemic recirculation. Myocardial redistribution of thallium-201 in states of chronically reduced perfusion cannot be the result of increased myocardial extraction efficiency, but rather, is the result of the slower intrinsic cellular washout rate at reduced perfusion levels

Influence of high energy phosphate metabolism in postischemic myocardial dysfunction using magnetic resonance spectroscopy; Influencia dos fosfatos de alta energia na funcao ventricular em pacientes com infarto do miocardio avaliada pela resonancia magnetica

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Kalil Filho, Roberto [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

1998-05-01

The recovery of left ventricular function after reperfusion is delayed in general by several hours, days or weeks and this phenomenon is known as myocardial stunning. One of the theories to explain the pathogenesis of this postischemic myocardial dysfunction is the production of not enough energy by mitochondria, leading to decreased adenosine-triphosphate (ATP) levels. We evaluated the influence of high energy phosphate metabolism in postischemic myocardial dysfunction, using magnetic resonance spectroscopy in patients with acute anterior wall myocardial infarction, successfully reperfused, within the first six hours from the onset of the symptoms. Twenty-nine patients were studied in the acute phase (on average four days after the onset of myocardial infarction) and 21 repeated the examination in the follow-up phase (average 39 days). Regional left ventricular function was evaluated by cine-resonance and high energy phosphate metabolism by phosphorus-31 spectroscopy, using the phosphocreatine {beta} ATP (P Cr/{beta}ATP) ratio. The existence of myocardial stunning was suggested by the improvement of the related regional contractility during the follow-up. The contractility improved in the septal wall from 2.46{+-} 0.68 to 1.54 {+-} 0.78 (p<0.001), in the anteroseptal wall from 2.0 {+-} 0.89 to 1.40 {+-} 0.75 (p<0.001) and in the anterior wall from 2.37 {+-} 0.71 to 1.41 {+-} 0.59 (p<0.001). The P Cr/{beta}ATP ratio did not change from acute to follow-up phase (1.51 {+-} 0.17 vs. 1.53 {+-} 0.17; p = 0.6). This study suggests that decreased high energy phosphate metabolism after reperfusion does not have an important role in the genesis of the myocardial stunning in patients with acute anterior wall myocardial infarction. (author) 25 refs., 9 figs., 1 tab.

Myocardial infarction in Swedish subway drivers.

Science.gov (United States)

Bigert, Carolina; Klerdal, Kristina; Hammar, Niklas; Gustavsson, Per

2007-08-01

Particulate matter in urban air is associated with the risk of myocardial infarction in the general population. Very high levels of airborne particles have been detected in the subway system of Stockholm, as well as in several other large cities. This situation has caused concern for negative health effects among subway staff. The aim of this study was to investigate whether there is an increased incidence of myocardial infarction among subway drivers. Data from a population-based case-control study of men aged 40-69 in Stockholm County in 1976-1996 were used. The study included all first events of myocardial infarction in registers of hospital discharges and deaths. The controls were selected randomly from the general population. National censuses were used for information on occupation. Altogether, 22 311 cases and 131 496 controls were included. Among these, 54 cases and 250 controls had worked as subway drivers. The relative risk of myocardial infarction among subway drivers was not increased. It was 0.92 [95% confidence interval (95% CI) 0.68-1.25] when the subway drivers were compared with other manual workers and 1.06 (95% CI 0.78-1.43) when the subway drivers were compared with all other gainfully employed men. Subgroup analyses indicated no influence on the risk of myocardial infarction from the duration of employment, latency time, or time since employment stopped. Subway drivers in Stockholm do not have a higher incidence of myocardial infarction than other employed persons.

Maintaining knife sharpness in industrial meat cutting: A matter of knife or meat cutter ability.

Science.gov (United States)

Karltun, J; Vogel, K; Bergstrand, M; Eklund, J

2016-09-01

Knife sharpness is imperative in meat cutting. The aim of this study was to compare the impact of knife blade steel quality with meat cutters' individual ability to maintain the cutting edge sharp in an industrial production setting. Twelve meat cutters in two different companies using three different knives during normal production were studied in this quasi-experimental study. Methods included were measuring knife cutting force before and after knife use, time knives were used, ratings of sharpness and discomfort and interviews. Results showed that the meat cutters' skill of maintaining sharpness during work had a much larger effect on knife sharpness during work than the knife steel differences. The ability was also related to feelings of discomfort and to physical exertion. It was found that meat cutters using more knives were more likely to suffer from discomfort in the upper limbs, which is a risk for developing MSD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lacosamide and Levetiracetam Have No Effect on Sharp-Wave Ripple Rate.

Science.gov (United States)

Kudlacek, Jan; Chvojka, Jan; Posusta, Antonin; Kovacova, Lubica; Hong, Seung Bong; Weiss, Shennan; Volna, Kamila; Marusic, Petr; Otahal, Jakub; Jiruska, Premysl

2017-01-01

Pathological high-frequency oscillations are a novel marker used to improve the delineation of epileptogenic tissue and, hence, the outcome of epilepsy surgery. Their practical clinical utilization is curtailed by the inability to discriminate them from physiological oscillations due to frequency overlap. Although it is well documented that pathological HFOs are suppressed by antiepileptic drugs (AEDs), the effect of AEDs on normal HFOs is not well known. In this experimental study, we have explored whether physiological HFOs (sharp-wave ripples) of hippocampal origin respond to AED treatment. The results show that application of a single dose of levetiracetam or lacosamide does not reduce the rate of sharp-wave ripples. In addition, it seems that these new generation drugs do not negatively affect the cellular and network mechanisms involved in sharp-wave ripple generation, which may provide a plausible explanation for the absence of significant negative effects on cognitive functions of these drugs, particularly on memory.

Relationship between availability of the collateral circulation and ischemic time for myocardial viability in patients with acute myocardial infarction. Assessment by technetium-99m tetrofosmin single photon emission computed tomography

International Nuclear Information System (INIS)

Kanamori, Norio; Kondo, Makoto; Fukuoka, Yoshitomo; Higuchi, Hirokazu; Kubota, Tomoyuki; Matsuoka, Ryota; Araki, Makoto; Tanio, Hitoshi; Doyama, Kiyoshi

2007-01-01

Myocardial accumulation before reperfusion therapy of a radioactive tracer in the completely occluded region, conceivably reflects the viability of myocytes and degree of collateral circulation. To confirm this, the present study examined the relationship in the title. Subjects were 33 patients (F 7, M 26; average age 65 y) of the first 1-branch acute myocardial infarction and of TIMI (thrombolysis in myocardial infarction trial) grade 0 who recovered to TIMI 3 within 12 hr after attack: 99m Tc-tetrofosmin, 740 MBq, was intravenously injected before reperfusion and just after which, SPECT imaging (TF-SPECT) was conducted with Toshiba E. CAM, and regional severity score index (RSSI) (0-3) was calculated. About 1 week later, to see the myocardial viability in the chronic phase, GITl (Glucose-Insulin- 201 Tl) (111 MBq) SPECT was performed 30 min after its injection to calculate RSSI as above, and the echocardiography with ALOKA Pro Sound SSD-4000 or SIEMENS Acuson SEQUOIA C256 was done to calculate the regional wall motion score index (RWMSI) (0-4). RWMSI was found significantly correlated with TF-RSSI, the group with the better collateral circulation (TF-RSSI, 1.9 or less) exhibited significantly lower GITl-RSSI and RWMSI, and correlation between the ischemic time and neither TF-RSSI, GITl-RSSI nor RWMSI was found. Thus under these conditions, the development of collateral vessels was found to have potential protective effects on myocardium independently on the ischemic time. (T.I.)

High fat diet-induced glucose intolerance impairs myocardial function, but not myocardial perfusion during hyperaemia: a pilot study

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van den Brom Charissa E

2012-06-01

Full Text Available Abstract Background Glucose intolerance is a major health problem and is associated with increased risk of progression to type 2 diabetes mellitus and cardiovascular disease. However, whether glucose intolerance is related to impaired myocardial perfusion is not known. The purpose of the present study was to study the effect of diet-induced glucose intolerance on myocardial function and perfusion during baseline and pharmacological induced hyperaemia. Methods Male Wistar rats were randomly exposed to a high fat diet (HFD or control diet (CD (n = 8 per group. After 4 weeks, rats underwent an oral glucose tolerance test. Subsequently, rats underwent (contrast echocardiography to determine myocardial function and perfusion during baseline and dipyridamole-induced hyperaemia (20 mg/kg for 10 min. Results Four weeks of HFD feeding resulted in glucose intolerance compared to CD-feeding. Contractile function as represented by fractional shortening was not altered in HFD-fed rats compared to CD-fed rats under baseline conditions. However, dipyridamole increased fractional shortening in CD-fed rats, but not in HFD-fed rats. Basal myocardial perfusion, as measured by estimate of perfusion, was similar in CD- and HFD-fed rats, whereas dipyridamole increased estimate of perfusion in CD-fed rats, but not in HFD-fed rats. However, flow reserve was not different between CD- and HFD-fed rats. Conclusions Diet-induced glucose intolerance is associated with impaired myocardial function during conditions of hyperaemia, but myocardial perfusion is maintained. These findings may result in new insights into the effect of glucose intolerance on myocardial function and perfusion during hyperaemia.

Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

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Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem [Department of Nuclear Medicine, Institute of Nuclear Medicine and Allied Sciences, Brig. S. K. Mazumdar Road, 110054, Delhi (India)

2004-04-01

It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of {sup 201}Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of {sup 201}Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium

Gated spect myocardial perfusion scintigraphy for identifying septal perfusion artifacts in left bundle branch block

International Nuclear Information System (INIS)

Afzal, M.S.; Imran, M.B.; Akhtar, M.S.; Muhammand, K.; Nadeem, A.; Aslam, N.; Khurshid, S.J.; Farooq, U.I.; Sohaib, M.

2006-01-01

To determine the role of gated Single Photon Emission Computed Tomography (SPECT) for accurate assessment of myocardial perfusion scintigraphy (MPS) of patients with left bundle branch block (LBBB). MPS data of patients with LBBB was analyzed. Resting gated SPECT MPS was performed after an injection of 740 MBq 99mTc-MIBI in 10 normal and 25 subjects with LBBB (with low probability of coronary artery disease). Visual and quantitative analyses were done on non-gated (NG), end diastolic (ED), end systolic (ES) images. Calculations included septal to lateral wall ratio (SLR), myocardial thickening (MT=% increase in counts during systole) at end systolic phase and myocardial thickening at peak level (% peak MT). Septal hypoperfusion was noted in 19 (76%) patients on NG images and in only 1 (4%) patient on gated SPECT ED images. On NG images of LBBB group, SLR was lower than in controls (0.68 +- 0.07 vs. 0.87 +- 0.05, p<0.001). SLR of LBBB patients approached to that of control group in gated SPECT ED data (0.86 +- 0.06 vs 0.88 +- 0.06, p=ns). Myocardial thickening at ES for septum was markedly lower in LBBB group than in controls (21.83% +- 10.86 vs. 66.32% +- 20.15, p<0.001). (author)

Monitoring of myocardial edema following acute myocardial infarction

International Nuclear Information System (INIS)

Tahir, E.; Sinn, M.; Avanesov, M.; Wien, J.; Saering, D.; Stehning, C.; Radunski, U. K.; Muellerleile, K.; Adam, G.; Lund, G. K.

2015-01-01

Full text: Currently, myocardial edema monitoring after acute myocardial infarction (AMI) is based on visualization of the region with increased signal-intensity on T2-weighted images. Native T1 and T2 mapping are promising novel MRI techniques to quantitatively assess myocardial edema. The purpose of the study was to quantitatively evaluate resorption of myocardial edema following AMI by native T1 and T2 -mapping cardiac magnetic resonance imaging (CMR). CMR (1.5 Tesla Philips Achieva) was performed in 30 patients four times after reperfused AMI at baseline (BL) at 9±6 days after infarction and at 7±1 weeks (follow-up 1, FU1), 3.6±0.5 months (FU2) and 6.5±0.7 months (FU3), respectively. Edema sensitive black-blood T2-weighted (T2w) STIR CMR was performed on end-diastolic LV short-axes. A free-breathing, navigatorgated multi-echo sequence was used for short-axis T2 mapping. T1 mapping was performed using the modified look-locker inversion recovery (MOLLI) sequence. T2 maps were calculated from nine and T1 maps from eight echoes using a dedicated plug-in written for OsiriX software. Two experienced observers independently evaluated T2w-CMR as well as T1 and T2 mapping using the HeAT-Software applying a threshold method. Size of edema and prolongation of the native T1- or T2-time was measured using a cutoff >2SD of remote normal myocardium. Edema size continuously decreased from BL with 32.8 %LV to 24.6 %LV at FU1, to 19.1 %LV at FU2 and to 16.4 %LV at FU3 using T2w-CMR. An almost identical decrease of edema size was observed using native T1 and T2 - mapping. T2 times only decreased between BL from 79±5 ms to 73±2 ms at FU1 (P<0.05), but no further change was observed at later time points with 70±5 ms at FU2 and 70±6 ms at FU3. At all time points the T2 times of remote normal myocardium were about 50±2 ms and significantly lower compared to the edema zone. Also native T1 time within the edema was with 1253 ±103 ms significantly increased compared to remote

Jasper Sharp - mees, kes jättis varasema töö, et vaadata Jaapani filme / Jasper Sharp ; intervjueerinud Helen Merila

Index Scriptorium Estoniae

Sharp, Jasper, 1971-

2011-01-01

Euroopa kultuuripealinn Tallinn 2011 programmi osana ning koostöös Zipangu Fest'iga korraldatakse Tallinna Kinomajas 25.-28. aug.-ni Aasia sõltumatute filmide festival EVA - East via Asia. Festivali kuraator, veebisaidi Midnight Eye kaastoimetaja Jasper Sharp endast, festivalist, Jaapani sõltumatust kinost tänapäeval. Festivali kava

A report on SHARP (Spacecraft Health Automated Reasoning Prototype) and the Voyager Neptune encounter

Science.gov (United States)

Martin, R. G. (Editor); Atkinson, D. J.; James, M. L.; Lawson, D. L.; Porta, H. J.

1990-01-01

The development and application of the Spacecraft Health Automated Reasoning Prototype (SHARP) for the operations of the telecommunications systems and link analysis functions in Voyager mission operations are presented. An overview is provided of the design and functional description of the SHARP system as it was applied to Voyager. Some of the current problems and motivations for automation in real-time mission operations are discussed, as are the specific solutions that SHARP provides. The application of SHARP to Voyager telecommunications had the goal of being a proof-of-capability demonstration of artificial intelligence as applied to the problem of real-time monitoring functions in planetary mission operations. AS part of achieving this central goal, the SHARP application effort was also required to address the issue of the design of an appropriate software system architecture for a ground-based, highly automated spacecraft monitoring system for mission operations, including methods for: (1) embedding a knowledge-based expert system for fault detection, isolation, and recovery within this architecture; (2) acquiring, managing, and fusing the multiple sources of information used by operations personnel; and (3) providing information-rich displays to human operators who need to exercise the capabilities of the automated system. In this regard, SHARP has provided an excellent example of how advanced artificial intelligence techniques can be smoothly integrated with a variety of conventionally programmed software modules, as well as guidance and solutions for many questions about automation in mission operations.

Needlestick and Sharp Instruments Injuries among Brazilian Dentistry Students

Science.gov (United States)

Fernandes, Liege Helena Freitas; Nunes, Wanúbia Barbosa; Silva, Larissa Costa; Wanderley, Rayssa Lucena; Barros, Criseuda Maria Benício; Cavalcanti, Alessandro Leite

2017-01-01

Background: The occurrence of occupational accidents is common among students and dentists. The present study is aimed to evaluate the prevalence and characteristics of needlestick and sharp instrument injuries among dentistry students. Materials and Methods: A documentary research was carried out with data being obtained from the analysis of 137 medical records of injuries caused by needlestick and sharp instruments occurring in the period from 2012 to 2016 and were analyzed regarding the characteristics of the victim (gender and age) and the accident (year, time, environment, and time interval between exposure and search for care). Data were organized in the Statistical Package for Social Sciences software version 18 and were presented through descriptive statistics. Results: The occurrence of accidents was high (43.1%), with the predominance of female victims (66.1%) and aged up to 23 years (55.9%). The majority of events occurred in the afternoon (54.4%), in the clinical setting (70.7%), and in 75% of the cases, the search for care occurred within 2 h after exposure. Conclusion: Accidents with needlestick and sharp instruments have high frequency and involve mainly female students. They are more common in the afternoon and in the clinical setting and the time interval was between exposure and the search for care complied with recommendations of the Brazilian legislation. PMID:28566861

SHARP1: A revised systematic human action reliability procedure

International Nuclear Information System (INIS)

Wakefield, D.J.; Parry, G.W.; Hannaman, G.W.; Spurgin, A.J.

1990-12-01

Individual plant examinations (IPE) are being performed by utilities to evaluate plant-specific vulnerabilities to severe accidents. A major tool in performing an IPE is a probabilistic risk assessment (PRA). The importance of human interactions in determining the plant response in past PRAs is well documented. The modeling and quantification of the probabilities of human interactions have been the subjects of considerable research by the Electric Power Research Institute (EPRI). A revised framework, SHARP1, for incorporating human interactions into PRA is summarized in this report. SHARP1 emphasizes that the process stages are iterative and directed at specific goals rather than being performed sequentially in a stepwise procedure. This expanded summary provides the reader with a flavor of the full report content. Excerpts from the full report are presented, following the same outline as the full report. In the full report, the interface of the human reliability analysis with the plant logic model development in a PRA is given special attention. In addition to describing a methodology framework, the report also discusses the types of human interactions to be evaluated, and how to formulate a project team to perform the human reliability analysis. A concise description and comparative evaluation of the selected existing methods of quantification of human error are also presented. Four case studies are also provided to illustrate the SHARP1 process

Evaluation of myocardial involvement in Duchenne progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

International Nuclear Information System (INIS)

Kawai, Naoki; Yamamoto, Shuhei; Okada, Mitsuhiro

1983-01-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. The qualitative analysis was performed in anterior, 3 left anterior oblique and left lateral projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in LV posterolateral or posterior walls (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle changes or thoracic deformities assessed by transmission computed tomography. Slightly increased thallium-201 activity in RV free wall and lungs was shown in nine and one patient, respectively. The extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. The myocardial scintigraphic changes were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies in 2 to 3 years. It was concluded that the thallium myocardial perfusion imaging was a useful clinical technique to evaluate the cardiomyopathy in Duchenne progressive muscular dystrophy. (author)

Evaluation of myocardial involvement in Duchenne progressive muscular dystrophy with thallium-201 myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Kawai, Naoki; Yamamoto, Shuhei; Okada, Mitsuhiro (Nagoya Univ. (Japan). Faculty of Medicine)

1983-12-01

Myocardial involvement in progressive muscular dystrophy of the Duchenne type was evaluated in 19 patients using thallium-201 myocardial perfusion imaging. The qualitative analysis was performed in anterior, 3 left anterior oblique and left lateral projection images by three experienced physicians. Distinct perfusion defects were shown in 13 patients, especially in LV posterolateral or posterior walls (11 patients). There was no significant relationship between the presence of perfusion defects and the skeletal muscle changes or thoracic deformities assessed by transmission computed tomography. Slightly increased thallium-201 activity in RV free wall and lungs was shown in nine and one patient, respectively. The extensive perfusion defects were shown in 2 patients who died of congestive heart failure 1 to 2 years after the scintigraphic study. The myocardial scintigraphic changes were considered to be minimal in 7 of 9 patients who underwent two serial scintigraphic studies in 2 to 3 years. It was concluded that the thallium myocardial perfusion imaging was a useful clinical technique to evaluate the cardiomyopathy in Duchenne progressive muscular dystrophy.

Status report on SHARP coupling framework.

Energy Technology Data Exchange (ETDEWEB)

Caceres, A.; Tautges, T. J.; Lottes, J.; Fischer, P.; Rabiti, C.; Smith, M. A.; Siegel, A.; Yang, W. S.; Palmiotti, G.

2008-05-30

This report presents the software engineering effort under way at ANL towards a comprehensive integrated computational framework (SHARP) for high fidelity simulations of sodium cooled fast reactors. The primary objective of this framework is to provide accurate and flexible analysis tools to nuclear reactor designers by simulating multiphysics phenomena happening in complex reactor geometries. Ideally, the coupling among different physics modules (such as neutronics, thermal-hydraulics, and structural mechanics) needs to be tight to preserve the accuracy achieved in each module. However, fast reactor cores in steady state mode represent a special case where weak coupling between neutronics and thermal-hydraulics is usually adequate. Our framework design allows for both options. Another requirement for SHARP framework has been to implement various coupling algorithms that are parallel and scalable to large scale since nuclear reactor core simulations are among the most memory and computationally intensive, requiring the use of leadership-class petascale platforms. This report details our progress toward achieving these goals. Specifically, we demonstrate coupling independently developed parallel codes in a manner that does not compromise performance or portability, while minimizing the impact on individual developers. This year, our focus has been on developing a lightweight and loosely coupled framework targeted at UNIC (our neutronics code) and Nek (our thermal hydraulics code). However, the framework design is not limited to just using these two codes.

Effect of streptozotocin-induced diabetes on myocardial blood flow reserve assessed by myocardial contrast echocardiography in rats

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Weytjens Caroline

2008-09-01

Full Text Available Abstract The role of structural and functional abnormalities of small vessels in diabetes cardiomyopathy remains unclear. Myocardial contrast echocardiography allows the quantification of myocardial blood flow at rest and during dipyridamole infusion. The aim of the study was to determine the myocardial blood flow reserve in normal rats compared with Streptozotocin-induced diabetic rats using contrast echocardiography. Methods We prospectively studied 40 Wistar rats. Diabetes was induced by intravenous streptozotocin in 20 rats. All rats underwent baseline and stress (dipyridamole: 20 mg/kg high power intermittent imaging in short axis view under anaesthesia baseline and after six months. Myocardial blood flow was determined and compared at rest and after dipyridamole in both populations. The myocardial blood flow reserve was calculated and compared in the 2 groups. Parameters of left ventricular function were determined from the M-mode tracings and histological examination was performed in all rats at the end of the study. Results At six months, myocardial blood flow reserve was significantly lower in diabetic rats compared to controls (3.09 ± 0.98 vs. 1.28 ± 0.67 ml min-1 g-1; p Conclusion In this animal study, diabetes induced a functional alteration of the coronary microcirculation, as demonstrated by contrast echocardiography, a decrease in capillary density and of the cardiac systolic function. These findings may offer new insights into the underlying mechanisms of diabetes cardiomyopathy.

Evaluation of myocardial damage and cardiac residual capacity by Tl-201 myocardial scintigraphy in valvular heart diseases

International Nuclear Information System (INIS)

Indo, Shunju

1992-01-01

This study was performed to clarify whether the extent-score (Ex-Score) calculated by Tl-201 myocardial scintigraphy is a reliable indicator of the severity of myocardial damage and cardiac residual capacity in valvular heart diseases. The subjects consisted of 38 patients (10 with aortic regurgitation (AR), 4 with aortic stenosis (AS), 13 with mitral regurgitation (MR) and 11 with mitral stenosis (MS)). Ex-Scores were significantly correlated with the severity of myocardial damage found in biopsied specimens obtained intraoperatively (correlation efficiency to Ex-Score with cell diameter in AR, % fibrosis in AR, cell diameter in AS, electron microscopic score in MR and % fibrosis in MS was 0.873, 0.734, 0.970, 0.913 and 0.659, respectively). Ex-Scores were also correlated with cardiac residual capacity determined by radioisotope angiography (correlation efficiency to Ex-Score with %Δ ejection fraction in AR, %Δ end-systolic volume in MR, %Δ end-diastolic volume in MS was -0.764, 0.790 and -0.763, respectively). These results suggest that the severity of myocardial damage and cardiac residual capacity can be estimated by Tl-201 myocardial scintigraphy (Ex-Score) in valvular heart diseases. (author)

Sharp Embeddings of Besov Spaces with Logarithmic Smoothness

Czech Academy of Sciences Publication Activity Database

Gurka, P.; Opic, Bohumír

2005-01-01

Roč. 18, č. 1 (2005), s. 81-110 ISSN 1139-1138 R&D Projects: GA ČR(CZ) GA201/01/0333 Institutional research plan: CEZ:AV0Z10190503 Keywords : Besov spaces wirh logarithmic smoothness * Lorentz-Zygmund spaces * sharp embeddings Subject RIV: BA - General Mathematics

A faunistic study of genus Chasmogenus Sharp, 1882 of China (Coleoptera, Hydrophilidae).

Science.gov (United States)

Jia, Fenglong; Tang, Yu-Dan

2018-01-01

Chasmogenus Sharp, 1882 is newly reported from the Chinese Mainland. A new species, C. parorbus sp. n. , is described from China (Yunnan). Chasmogenus orbus Watanabe, 1987 is reported from Hong Kong, the first record outside Japan. Chasmogenus abnormalis (Sharp, 1890) is reported from the Chinese mainland for the first time. The male genitalia of each species are illustrated. A key to the Chinese species of the genus is provided.

Clinical significance of myocardial 123I-BMIPP imaging in patients with myocardial infarction

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi; Shindoh, Takashi; Honda, Minoru

1997-01-01

We studied 55 patients with myocardial infarction (MI), 14 patients with recent MI (RMI) and 41 patients with old MI (OMI), and myocardial images were divided into 17 segments and myocardial uptake of the radionuclide was graded from 0 (normal) to 3 (maximal abnormality). In 28 patients we compared segmental defect score (SDS) with wall motion index (WMI) which were obtained by centerline method at the corresponded segments. As a whole, the mean total defect scores (TDSs) of BMIPP and exercise stress (Ex) were similar and they were greater than the mean TDS of resting perfusion. In 30 patient TDS of BMIPP was greater than that of TDS of resting perfusion. In 24 patients perfusion abnormality developed by Ex and the location of BMIPP abnormality coincided with the abnormality of Ex. But in the other 6 patients Ex did not induce any abnormality and they were all RMI and infarcted coronary artery was patent. However in the group with TDS of BMIPP identical to TDS of resting perfusion (25 patients), 92% did not show myocardial perfusion abnormality after Ex. In the comparison of SDS and WMI, myocardial segments were divided into 3 groups; both SDSs of BMIPP and resting perfusion were normal or borderline abnormality (Group 1, 82 segments), SDS of resting perfusion was normal or borderline and SDS of BMIPP was definitely abnormal (Group 2, 10 segments) and both SDSs of BMIPP and resting perfusion were definitely abnormal (Group 3, 48 segments). In Group 1, WMS was significantly greater than those of Group 2 and Group 3. But there was no difference between Group 2 and 3. These findings suggested that in the segments with mismatch between BMIPP and resting perfusion reflects stunned myocardium. (K.H.)

Detection of myocardial ischemia of hypertrophic cardiomyopathy with gated 99Tcm-MIBI myocardial perfusion imaging

International Nuclear Information System (INIS)

Jia Peng; Guo Wanhua; Du Minghua; Gao Ling

2010-01-01

Objective: To evaluate the value of gated 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging in detection of myocardial ischemia in hypertrophic cardiomyopathy. Methods: Sixty-nine patients with clinically proven hypertrophic cardiomyopathy were divided into 2 groups using coronary angiogram as 'gold standard': positive group (n=19, narrowing ≥ 50%) and negative group (n=50, narrowing 99 Tc m -MIBI myocardial perfusion imaging was performed and positive in all 69 patients (41 males, 28 females, aged 35-75 years). Comparative analysis between the two groups was carried out using t-test. Results: In the positive group, reversible and irreversible perfusion defects were detected in 9 and 10 patients, respectively. Left ventricular ejection fraction (LVEF) increased to (69.1 ± 2.8)% in 8 patients and decreased to (42.8 ± 2.1)% in 11 patients. In the negative group, reversible and irreversible perfusion defects were found in 37 and 13 patients, respectively. LVEF increased to (70.8 ± 4.0)% in 38 patients and decreased to (48.9 ± 2.7)% in 12 patients. The values of ischemic area, severity and extent of perfusion defect, and LVEF were significantly different between the two groups (t=9.28, 16.51, 2.65; P 99 Tc m -MIBI myocardial perfusion imaging is valuable in assessing patients with hypertrophic cardiomyopathy. Detection for the presence or absence of coexisting coronary artery disease and myocardial ischemia has an important prognostic indication and management indication for these patients. (authors)

Use of resting myocardial scintigraphy during chest pain to exclude diagnosis of acute myocardial infarction

International Nuclear Information System (INIS)

Barbirato, Gustavo Borges; Azevedo, Jader Cunha de; Felix, Renata Christian Martins; Correa, Patricia Lavatori; Volschan, Andre; Viegas, Monica; Pimenta, Lucia; Dohmann, Hans Fernando Rocha; Mesquita, Evandro Tinoco; Mesquita, Claudio Tinoco

2009-01-01

Background: Images of myocardial perfusion taken during an episode of chest pain have been used for patients in the emergency department. Objective: To evaluate the operating characteristics of 99m Tc-Tetrofosmin scintigraphy during an episode of chest pain to exclude the diagnosis of cute myocardial infarction. Methods: One hundred and eight patients admitted with chest pain, or up to four hours after the end of symptoms and non diagnostic electrocardiogram, underwent resting scintigraphy and measurement of troponin I concentrations. Patients with a history of myocardial infarction (MI) were not excluded (24 patients). Troponin I concentrations were determined at admission and 6 hours later. Nuclear physicians performed a blind analysis of the images, and myocardial infarction was confirmed whenever troponin I level increase was three times that of the control. Results: Resting perfusion image was abnormal in all 6 patients with MI. Only 1 patient had a normal image and increased troponin levels. Fifty-five patients had positive images without MI, and 46 patients had normal images and troponin levels. The prevalence of the disease was 6.5%. The sensitivity and specificity of the resting images during an episode of chest pain to diagnose MI was 85.7% and 45.5%, respectively. The negative predictive value was 97.7%. Conclusion: Patients undergoing chest pain protocol with SPECT showed an excellent negative predictive value to exclude diagnosis of myocardial infarction. These results suggest that resting perfusion image is an important tool at the chest pain unit. (author)

Effect of eating on thallium-201 myocardial redistribution after myocardial ischemia

International Nuclear Information System (INIS)

Angello, D.A.; Wilson, R.A.; Palac, R.T.

1987-01-01

To determine whether eating a high-carbohydrate meal between initial and delayed postexercise thallium-201 (Tl-201) imaging affects detection of Tl-201 redistribution during exercise stress testing, 16 patients with stable angina performed 2 Tl-201 treadmill exercise stress tests within a 14-day interval. Immediately after initial postexercise imaging, patients either drank a commercially available instant breakfast preparation for the intervention test or drank an equivalent volume of water for the control test. Comparable exercise workloads were achieved by exercising patients to the same heart rate for both tests. The order of the 2 (intervention and control) tests were randomized. All patients had at least 1 region of Tl-201 myocardial redistribution on either their eating or control test scans, although only 7 of the 16 had positive treadmill exercise test responses. Forty-six regions showing Tl-201 myocardial redistribution were identified in all 144 regions examined. Significantly more of these regions were identified on control test scans than on eating test scans: 11 of 46 on both test scans, 6 of 46 only on eating test scans and 29 of 46 only on control scans (p less than 0.001). Consistent with results of the quantitative regional analysis, the percentage of Tl-201 clearance over 4 hours in the 46 Tl-201 myocardial redistribution regions was 39 +/- 8% for the eating tests and 29 +/- 8% for control tests (mean +/- standard deviation, p less than 0.003). In 4 patients diagnosis of transient ischemia would have been missed because their 14 Tl-201 myocardial redistribution regions were detected only on the control test scans

Asymptomatic myocardial ischemia following cold provocation

International Nuclear Information System (INIS)

Shea, M.J.; Deanfield, J.E.; deLandsheere, C.M.; Wilson, R.A.; Kensett, M.; Selwyn, A.P.

1987-01-01

Cold is thought to provoke angina in patients with coronary disease either by an increase in myocardial demand or an increase in coronary vascular resistance. We investigated and compared the effects of cold pressor stimulation and symptom-limited supine bicycle exercise on regional myocardial perfusion in 35 patients with stable angina and coronary disease and in 10 normal subjects. Regional myocardial perfusion was assessed with positron emission tomography and rubidium-82. Following cold pressor stimulation 24 of 35 patients demonstrated significant abnormalities of regional myocardial perfusion with reduced cation uptake in affected regions of myocardium: 52 +/- 9 to 43 +/- 9 (p less than 0.001 vs normal subjects). Among these 24 patients only nine developed ST depression and only seven had angina. In contrast, 29 of 35 patients underwent supine exercise, and abnormal regional myocardial perfusion occurred in all 29, with a reduction in cation intake from 48 +/- 10 to 43 +/- 14 (p less than 0.001 vs normal subjects). Angina was present in 27 of 29 and ST depression in 25 of 29. Although the absolute decrease in cation uptake was somewhat greater following cold as opposed to exercise, the peak heart rate after cold was significantly lower than that after exercise (82 +/- 12 vs 108 +/- 16 bpm, p less than 0.05). Peak systolic blood pressures after cold and exercise were similar (159 +/- 24 vs 158 +/- 28). Thus, cold produces much more frequent asymptomatic disturbances of regional myocardial perfusion in patients with stable angina and coronary disease than is suggested by pain or ECG changes

Quadrilateral mesh fitting that preserves sharp features based on multi-normals for Laplacian energy

Directory of Open Access Journals (Sweden)

Yusuke Imai

2014-04-01

Full Text Available Because the cost of performance testing using actual products is expensive, manufacturers use lower-cost computer-aided design simulations for this function. In this paper, we propose using hexahedral meshes, which are more accurate than tetrahedral meshes, for finite element analysis. We propose automatic hexahedral mesh generation with sharp features to precisely represent the corresponding features of a target shape. Our hexahedral mesh is generated using a voxel-based algorithm. In our previous works, we fit the surface of the voxels to the target surface using Laplacian energy minimization. We used normal vectors in the fitting to preserve sharp features. However, this method could not represent concave sharp features precisely. In this proposal, we improve our previous Laplacian energy minimization by adding a term that depends on multi-normal vectors instead of using normal vectors. Furthermore, we accentuate a convex/concave surface subset to represent concave sharp features.

Soft yet Sharp Interfaces in a Vertex Model of Confluent Tissue

Science.gov (United States)

Sussman, Daniel M.; Schwarz, J. M.; Marchetti, M. Cristina; Manning, M. Lisa

2018-01-01

How can dense biological tissue maintain sharp boundaries between coexisting cell populations? We explore this question within a simple vertex model for cells, focusing on the role of topology and tissue surface tension. We show that the ability of cells to independently regulate adhesivity and tension, together with neighbor-based interaction rules, lets them support strikingly unusual interfaces. In particular, we show that mechanical- and fluctuation-based measurements of the effective surface tension of a cellular aggregate yield different results, leading to mechanically soft interfaces that are nevertheless extremely sharp.

Myocardial SPECT in children with sickle cell disease

International Nuclear Information System (INIS)

Maunoury, C.; Hallaj, I.; Barritault, L.; Acar, P.; Montalembert, M. de

2002-01-01

Aim: While cerebral and bones strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Conventional techniques such as exercise testing and echocardiography have a low sensitivity and specificity to detect myocardial ischemia in patients with SCD. The aim of this prospective study was to assess myocardial perfusion with 201 Tl SPECT in children with SCD. Materials and Methods: Twenty-two patients, aged 12 ± 4 years, were included. Myocardial perfusion was assessed by 201 Tl SPECT after stress and 3 hours later after reinjection on a single head gammacamera equipped with a LEAP collimator (64x64 matrix size format, 30 projections over 180 0 , 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Results: Myocardial perfusion was impaired in 13/22 patients: 8 had reversible defects and 5 had fixed defects. The left ventricular cavity was dilated in 13/22 patients. The mean LVEF was 63 ± 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. Conclusion: Myocardial perfusion is frequently impaired in children with SCD. Treatment with hydroxyurea should be considered in SCD patients with perfusion defects

Measurement of the infarcted area by 201Tl myocardial emission CT

International Nuclear Information System (INIS)

Tamaki, Shunichi; Murakami, Tomoyuki; Kambara, Hirofumi

1982-01-01

201 Tl-ECT was performed in 28 cases 4 weeks after the onset of acute myocardial infarction to calculate the volume of infarction for comparison with the CK-MB infarction size obtained in the acute phase. The infarct area obtained by two-dimensional 201 Tl scintigraphy in 18 cases treated by the conventional method showed a positive correlation with the CK-MB infarct size, but the volume of infarction by 201 Tl-ECT produced a better correlation. In the group with successful thrombolysis, the serum CK-MB level reached a peak soon after the onset, accompanied by release of more CK-MB for a constant volume of infarction obtained by 201 Tl-ECT, as compared with the group with unsuccessful thrombolysis or conventional therapy. This suggests the involvement of washout phenomenon by reperfusion. Although there are some limitations, the three-dimensional detection of the distribution of myocardial blood flow by 201 Tl-ECT is useful, covering disadvantages of two-dimensional images. (Chiba, N.)

Validation of PSF-based 3D reconstruction for myocardial blood flow measurements with Rb-82 PET

DEFF Research Database (Denmark)

Tolbod, Lars Poulsen; Christensen, Nana Louise; Møller, Lone W.

images, filtered backprojection (FBP). Furthermore, since myocardial segmentation might be affected by image quality, two different approaches to segmentation implemented in standard software (Carimas (Turku PET Centre) and QPET (Cedar Sinai)) are utilized. Method:14 dynamic rest-stress Rb-82 patient......-scans performed on a GE Discovery 690 PET/CT were included. Images were reconstructed in an isotropic matrix (3.27x3.27x3.27 mm) using PSF (SharpIR: 3 iterations and 21 subsets) and FBP (FORE FBP) with the same edge-preserving filter (3D Butterworth: cut-off 10 mm, power 10). Analysis: The dynamic PET......Aim:The use of PSF-based 3D reconstruction algorithms (PSF) is desirable in most clinical PET-exams due to their superior image quality. Rb-82 cardiac PET is inherently noisy due to short half-life and prompt gammas and would presumably benefit from PSF. However, the quantitative behavior of PSF...

A faunistic study of genus Chasmogenus Sharp, 1882 of China (Coleoptera, Hydrophilidae

Directory of Open Access Journals (Sweden)

Fenglong Jia

2018-02-01

Full Text Available Chasmogenus Sharp, 1882 is newly reported from the Chinese Mainland. A new species, C. parorbus sp. n., is described from China (Yunnan. Chasmogenus orbus Watanabe, 1987 is reported from Hong Kong, the first record outside Japan. Chasmogenus abnormalis (Sharp, 1890 is reported from the Chinese mainland for the first time. The male genitalia of each species are illustrated. A key to the Chinese species of the genus is provided.

Quantitative analysis of 123I-metaiodobenzylguanidine myocardial scintigraphy by myocardial uptake using a phantom

International Nuclear Information System (INIS)

Momose, Mitsuru; Kobayashi, Hideki; Kashikura, Kenichi; Kanaya, Shinichi; Maki, Masako; Hosoda, Saichi; Kusakabe, Kiyoko

1994-01-01

To evaluate the quantitative analysis of 123 I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, total injected dose measured by first pass (FP) method (T FP ) was compared with that measured by phantom method using an acrylic phantom in 45 patients with cardiac disease. Heart per mediastinum ratio (H/M) was compared to myocardial uptake calculated with T FP . The total injected dose measured using the phantom in which the syringe was set in depth of 3.5 cm (T pham ) was correlated with T FP (r=0.73, p=0.0001). When T pham was corrected by body weight (c-T pham ), c-T pham showed better correlation with T FP . MU calculated by T FP (MU-FP) was well correlated with MU by c-T pham (MU-pham) (r=0.94, p=0.001). These results indicate that phantom method is sufficient to substitute for FP method. Though H/M was correlated with MU-FP (p<0.001), the interpatient variation was relatively large. Then the analysis by H/M is insufficient to substitute for the myocardial uptake. It is thought to be enough to use the phantom method on daily routine work, since this method is accurate and easy to quantitate the myocardial uptake of MIBG taking a short time. (author)

Optimal left ventricular lead position assessed with phase analysis on gated myocardial perfusion SPECT

International Nuclear Information System (INIS)

Boogers, Mark J.; Chen, Ji; Garcia, Ernest V.; Bommel, Rutger J. van; Borleffs, C.J.W.; Schalij, Martin J.; Wall, Ernst E. van der; Bax, Jeroen J.; Dibbets-Schneider, Petra; Hiel, Bernies van der; Younis, Imad Al

2011-01-01

The aim of the current study was to evaluate the relationship between the site of latest mechanical activation as assessed with gated myocardial perfusion SPECT (GMPS), left ventricular (LV) lead position and response to cardiac resynchronization therapy (CRT). The patient population consisted of consecutive patients with advanced heart failure in whom CRT was currently indicated. Before implantation, 2-D echocardiography and GMPS were performed. The echocardiography was performed to assess LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). The site of latest mechanical activation was assessed by phase analysis of GMPS studies and related to LV lead position on fluoroscopy. Echocardiography was repeated after 6 months of CRT. CRT response was defined as a decrease of ≥15% in LVESV. Enrolled in the study were 90 patients (72% men, 67±10 years) with advanced heart failure. In 52 patients (58%), the LV lead was positioned at the site of latest mechanical activation (concordant), and in 38 patients (42%) the LV lead was positioned outside the site of latest mechanical activation (discordant). CRT response was significantly more often documented in patients with a concordant LV lead position than in patients with a discordant LV lead position (79% vs. 26%, p<0.01). After 6 months, patients with a concordant LV lead position showed significant improvement in LVEF, LVESV and LVEDV (p<0.05), whereas patients with a discordant LV lead position showed no significant improvement in these variables. Patients with a concordant LV lead position showed significant improvement in LV volumes and LV systolic function, whereas patients with a discordant LV lead position showed no significant improvements. (orig.)

Flow Control Over Sharp-Edged Wings

Science.gov (United States)

2007-07-01

Gad-el-Hak (2001) as the ability to actively or passively manipulate a flow field to effect a desired change. The challenge is to achieve that change...combinations. Been able to independently control both is a great challenge . These requirements may appear too stringent for the sharp- edged airfoils...06 0𔄁 08 09 lic Vlc Figure 22: Pressure distributions for Model B at a=13 °. Stations I (left); 2 (right) 1 , -2 1 F - [12 1 -6a -16 08 -08 06 -06

Myocardial ischemia in Kawasaki disease

International Nuclear Information System (INIS)

Fukuda, Tsuyoshi

1993-01-01

The detection of myocardial ischemia is essential for evaluation of patients with Kawasaki disease, especially who have had coronary artery lesions. To evaluate the clinical efficacy of Tl-201 single photon emission computed tomography (SPECT) after dipyridamole infusion (maximum dose 0.70 mg/kg) for detecting myocardial ischemia, 44 patients with Kawasaki disease aged 7.7±4.8 years at the study and 10 age matched controls were observed. In the Kawasaki disease group, significant coronary artery stenosis was observed in 14, coronary aneurysm without stenosis in 18, the regression of the coronary aneurysms in 2 and without coronary lesions in 10 patients. In 24 of 44 patients, treadmill exercise stress test was also performed at the same period. Myocardial ischemic changes were observed in 11 patients, all combined with significant coronary artery stenosis. The sensitivity of SPECT for detection of overall coronary stenosis was 79%, coronary that of treadmill exercise test was only 33% (p<0.001). Furthermore, among the patients having significant coronary stenosis, the severity score was significantly elevated in patients who had electrocardiographic abnormal Q wave compared to those without abnormal Q wave (51.0±38.8 versus 20.0±12.1, p<0.05). These data suggest that the pharmacological stress scintigraphy using dipyridamole injection provides not only the accurate detection but quantitative evaluation of myocardial ischemia in these patients. This noninvasive technique may become one of the most useful index for detection and follow-up of myocardial ischemia in Kawasaki disease. (author)

Myocardial strains from 3D displacement encoded magnetic resonance imaging

International Nuclear Information System (INIS)

Kindberg, Katarina; Haraldsson, Henrik; Sigfridsson, Andreas; Engvall, Jan; Ingels, Neil B Jr; Ebbers, Tino; Karlsson, Matts

2012-01-01

The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE), make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts

Myocardial perfusion scintigraphy - possibilities of diagnosing CAD

International Nuclear Information System (INIS)

Tsonevska, A.

1998-01-01

A reviewing the diagnostic methods used in the intricate process of evaluating CAD patients in a attempt to establish the role played by radionuclide methods in the diagnostic strategy is done. The perfusion cardiotropic radiopharmaceuticals used and the various methods of evaluating myocardial are discussed. Although 210 Tl-chloride is the most widely used myocardial perfusion agent, recently 99m Tc-MIBI is proposed as an alternative because of its advantages. Myocardial perfusion assessment is done by various techniques depending on the specific aim, each of them having its proper advantages and shortcomings. The inference is reached that regardless of the routine practical implementation of myocardial perfusion scintigraphy and comprehensive studies along this line in course, there are problems still not well enough clarified awaiting solution

The Pathogenesis of Human Myocardial Infarction

Science.gov (United States)

Rona, George

1966-01-01

Coronary arteriography, dissection of the coronary arteries and histopathological examination of the heart were carried out in 150 autopsies to study the effect of coronary narrowing and occlusion, of the presence of collaterals, and of coronary artery predominance on the development of myocardial infarction. The thrombosis rate was related to the severity of coronary sclerosis. The development of collaterals was not enhanced by coronary sclerosis and occlusion, and collaterals did not protect the myocardium against reinfarction. Coronary occlusion was regularly demonstrable in recent myocardial infarct cases. The association of atrial and posterior ventricular infarcts was explained by occlusion of their common arterial branch. The interdependence between coronary sclerosis, thrombosis and myocardial infarction in human autopsy material emphasizes the importance of mural coronary artery disease in the genesis of coronary occlusion and myocardial infarction, and it is at variance with statistical data and experimental results. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:5924947

Myocardial potency of Bio-tea against Isoproterenol induced myocardial damage in rats.

Science.gov (United States)

Lobo, Reema Orison; Shenoy, Chandrakala K

2015-07-01

Kombucha (Bio-tea) is a beverage produced by the fermentation of sugared black tea using a symbiotic association of bacteria and yeasts. Traditional claims about Kombucha report beneficial effects such as antibiotic properties, gastric regulation, relief from joint rheumatism and positive influence on the cholesterol level, arteriosclerosis, diabetes, and aging problems. The present investigation was carried out to understand the preventive effect of Kombucha on heart weight, blood glucose, total protein, lipid profile and cardiac markers in rats with myocardial damage induced using Isoproterenol. As Bio-tea is produced by fermenting tea, the parameters were compared in rats pre-treated with normal black tea and Bio-tea for 30 days followed by subcutaneous injection of Isoproterenol (85 mg/kg body weight). Normal rats as well as Isoproterenol induced myocardial infarcted rats were also used, which served as controls. Isoproterenol induced myocardial infarcted control rats showed a significant increase in heart weight, blood glucose and cardiac markers and a decrease in plasma protein. Increased levels of cholesterol, triglycerides, low density lipids (LDL) and very low density lipids (VLDL) were also observed, while the high density lipid (HDL) content decreased. Bio-tea showed a higher preventive effect against myocardial infarction when compared to tea, as was observed by the significant reduction in heart weight, and blood glucose and increase in plasma albumin levels. Bio-tea significantly decreased cholesterol, triglycerides, LDL and VLDL while simultaneously increasing the levels of HDL. Similarly a decrease in leakage of cardiac markers from the myocardium was also observed.

The Myocardial Performance Index During Low Dose Dobutamine Echocardiography in Normals and Patients With a Recent Myocardial Infarction

DEFF Research Database (Denmark)

Nørager, Betina; Husic, Mirza; Møller, Jacob E

2004-01-01

BACKGROUND: Wall-motion analysis during low-dose dobutamine echocardiography (LDDE) is a semiquantitative measure of left ventricular contractile reserve after myocardial infarction (MI). The Doppler echocardiographic myocardial performance index (MPI) is a quantitative measure of combined left...

Stress myocardial scintigraphy in coronary artery disease

International Nuclear Information System (INIS)

Hata, Noritake; Koumi, Shin-ichi; Yasutake, Masahiro; Imaizumi, Takahiro; Saito, Tsutomu; Kishida, Hiroshi; Hayakawa, Hirokazu

1991-01-01

To evaluate the clinical significance of asymptomatic ischemic heart disease, exercise electrocardiography and stress myocardial scintigraphy were performed. These were correlated with symptoms during exercise tests and histories of myocardial infarction (MI). The study subjects consisted of 70 patients with coronary artery disease, including 34 with MI, and 36 without MI but with angina pectoris. Stress tests were performed using bicycle ergometer under electrocardiographic monitoring throughout the test. Transient myocardial ischemia was confirmed by perfusion defects on thallium myocardial imaging demonstrated immediately after exercise, but not 3 hours after the stress test. Asymptomatic ST depression was observed in 18 of 34 patients with MI (53%) and in 21 of the 36 patients with angina (58%); however, transient myocardial perfusion defects were confimred in 61% of the patients with MI (11 of 18 patients), but in only 33% of those with angina (7 of 21 patients). The difference was statistically significant (p<0.05). It was suggested that there are some differences in the clinical significance of asymptomatic ST depression between the patients with MI and those without MI but with angina pectoris. (author)

Feature-tracking myocardial strain analysis in acute myocarditis. Diagnostic value and association with myocardial oedema

Energy Technology Data Exchange (ETDEWEB)

Luetkens, Julian A.; Schlesinger-Irsch, Ulrike; Kuetting, Daniel L.; Dabir, Darius; Homsi, Rami; Schmeel, Frederic C.; Sprinkart, Alois M.; Naehle, Claas P.; Schild, Hans H.; Thomas, Daniel [University of Bonn, Department of Radiology, Bonn (Germany); Doerner, Jonas [University Hospital Cologne, Department of Radiology, Cologne (Germany); Fimmers, Rolf [University of Bonn, Department of Medical Biometry, Informatics, and Epidemiology, Bonn (Germany)

2017-11-15

To investigate the diagnostic value of cardiac magnetic resonance (CMR) feature-tracking (FT) myocardial strain analysis in patients with suspected acute myocarditis and its association with myocardial oedema. Forty-eight patients with suspected acute myocarditis and 35 control subjects underwent CMR. FT CMR analysis of systolic longitudinal (LS), circumferential (CS) and radial strain (RS) was performed. Additionally, the protocol allowed for the assessment of T1 and T2 relaxation times. When compared with healthy controls, myocarditis patients demonstrated reduced LS, CS and RS values (LS: -19.5 ± 4.4% vs. -23.6 ± 3.1%, CS: -23.0 ± 5.8% vs. -27.4 ± 3.4%, RS: 28.9 ± 8.5% vs. 32.4 ± 7.4%; P < 0.05, respectively). LS (T1: r = 0.462, P < 0.001; T2: r = 0.436, P < 0.001) and CS (T1: r = 0.429, P < 0.001; T2: r = 0.467, P < 0.001) showed the strongest correlations with T1 and T2 relaxations times. Area under the curve of LS (0.79) was higher compared with those of CS (0.75; P = 0.478) and RS (0.62; P = 0.008). FT CMR myocardial strain analysis might serve as a new tool for assessment of myocardial dysfunction in the diagnostic work-up of patients suspected of having acute myocarditis. Especially, LS and CS show a sufficient diagnostic performance and were most closely correlated with CMR parameters of myocardial oedema. (orig.)

Feature-tracking myocardial strain analysis in acute myocarditis. Diagnostic value and association with myocardial oedema

International Nuclear Information System (INIS)

Luetkens, Julian A.; Schlesinger-Irsch, Ulrike; Kuetting, Daniel L.; Dabir, Darius; Homsi, Rami; Schmeel, Frederic C.; Sprinkart, Alois M.; Naehle, Claas P.; Schild, Hans H.; Thomas, Daniel; Doerner, Jonas; Fimmers, Rolf

2017-01-01

To investigate the diagnostic value of cardiac magnetic resonance (CMR) feature-tracking (FT) myocardial strain analysis in patients with suspected acute myocarditis and its association with myocardial oedema. Forty-eight patients with suspected acute myocarditis and 35 control subjects underwent CMR. FT CMR analysis of systolic longitudinal (LS), circumferential (CS) and radial strain (RS) was performed. Additionally, the protocol allowed for the assessment of T1 and T2 relaxation times. When compared with healthy controls, myocarditis patients demonstrated reduced LS, CS and RS values (LS: -19.5 ± 4.4% vs. -23.6 ± 3.1%, CS: -23.0 ± 5.8% vs. -27.4 ± 3.4%, RS: 28.9 ± 8.5% vs. 32.4 ± 7.4%; P < 0.05, respectively). LS (T1: r = 0.462, P < 0.001; T2: r = 0.436, P < 0.001) and CS (T1: r = 0.429, P < 0.001; T2: r = 0.467, P < 0.001) showed the strongest correlations with T1 and T2 relaxations times. Area under the curve of LS (0.79) was higher compared with those of CS (0.75; P = 0.478) and RS (0.62; P = 0.008). FT CMR myocardial strain analysis might serve as a new tool for assessment of myocardial dysfunction in the diagnostic work-up of patients suspected of having acute myocarditis. Especially, LS and CS show a sufficient diagnostic performance and were most closely correlated with CMR parameters of myocardial oedema. (orig.)

Number-Phase Wigner Representation and Entropic Uncertainty Relations for Binomial and Negative Binomial States

International Nuclear Information System (INIS)

Amitabh, J.; Vaccaro, J.A.; Hill, K.E.

1998-01-01

We study the recently defined number-phase Wigner function S NP (n,θ) for a single-mode field considered to be in binomial and negative binomial states. These states interpolate between Fock and coherent states and coherent and quasi thermal states, respectively, and thus provide a set of states with properties ranging from uncertain phase and sharp photon number to sharp phase and uncertain photon number. The distribution function S NP (n,θ) gives a graphical representation of the complimentary nature of the number and phase properties of these states. We highlight important differences between Wigner's quasi probability function, which is associated with the position and momentum observables, and S NP (n,θ), which is associated directly with the photon number and phase observables. We also discuss the number-phase entropic uncertainty relation for the binomial and negative binomial states and we show that negative binomial states give a lower phase entropy than states which minimize the phase variance

Regional myocardial metabolism in patients with acute myocardial infarction assessed by positron emission tomography

International Nuclear Information System (INIS)

Schwaiger, M.; Brunken, R.; Grover-McKay, M.; Krivokapich, J.; Child, J.; Tillisch, J.H.; Phelps, M.E.; Schelbert, H.R.

1986-01-01

Positron emission tomography has been shown to distinguish between reversible and irreversible ischemic tissue injury. Using this technique, 13 patients with acute myocardial infarction were studied within 72 hours of onset of symptoms to evaluate regional blood flow and glucose metabolism with nitrogen (N)-13 ammonia and fluorine (F)-18 deoxyglucose, respectively. Serial noninvasive assessment of wall motion was performed to determine the prognostic value of metabolic indexes for functional tissue recovery. Segmental blood flow and glucose utilization were evaluated using a circumferential profile technique and compared with previously established semiquantitative criteria. Relative N-13 ammonia uptake was depressed in 32 left ventricular segments. Sixteen segments demonstrated a concordant decrease in flow and glucose metabolism. Regional function did not change over time in these segments. In contrast, 16 other segments with reduced blood flow revealed maintained F-18 deoxyglucose uptake consistent with remaining viable tissue. The average wall motion score improved significantly in these segments (p less than 0.01), yet the degree of recovery varied considerably among patients. Coronary anatomy was defined in 9 of 13 patients: patent infarct vessels supplied 8 of 10 segments with F-18 deoxyglucose uptake, while 10 of 13 segments in the territory of an occluded vessel showed concordant decreases in flow and metabolism (p less than 0.01). Thus, positron emission tomography reveals a high incidence of residual tissue viability in ventricular segments with reduced flow and impaired function during the subacute phase of myocardial infarction. Absence of residual tissue metabolism is associated with irreversible injury, while preservation of metabolic activity identifies segments with a variable outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of coronary artery reconstruction in maintaining myocardial viability. Quntitative determination of local myocardial circulation with 13NH3 myocardial positron emission tomography

International Nuclear Information System (INIS)

Kobayashi, Satoshi; Takaba, Toshihiro; Kume, Masato; Kashima, Toshitaka; Michihata, Tetsuro.

1996-01-01

Thirty patients (280 areas) whose bypass grafts remained patent after surgical reconstruction of the coronary artery were examined. Before and after reconstruction, local myocardial blood circulation in infarcted regions and post-stenotic regions was measured by 13 NH 3 myocardial positron emission computed tomography (PET) at rest or during physical exercise in order to evaluate the efficacy of coronary artery reconstruction. Before operation, mean blood flow in post-stenotic regions (n=198) was 65±15 ml/min/100 g at rest and 85±23 ml/min/100 g during exercise. After coronary artery bypass grafting (CABG), mean blood flow was increased to 78±21 ml/min/100 g at rest (p, 0.01) and 105±32 ml/min/100 g during exercise (p<0.01). In infarcted regions (n=82), mean blood flow before operation was 51±23 ml/min/100 g at rest and 69±23 ml/min/100 g during exercise. After CABG, it increased to 62±19 ml/min/100 g at rest (p<0.01) and 81±29 ml/min/100 g during exercise (p<0.01). Thus, significant increases in blood flow were observed in both post-stenotic and infarcted regions at rest and physical exercise after operation. The regions of infarction were divided into three groups based on local myocardial blood flow at rest before operation: Group I: greater than 45 ml/min/100 g (n=35); Group II: less than 45 ml/min/100 g (n=30) but greater than 30 ml/min/100 g; and Group III: less than 30 ml/min/100 g (n=30). The efficacy of reconstruction was compared among these groups. The group with preoperative myocardial blood flow greater than 30 ml/min/100 g had increased blood flow after operation, indicating myocardial viability. (author)

The Doppler echocardiographic myocardial performance index predicts left-ventricular dilation and cardiac death after myocardial infarction

DEFF Research Database (Denmark)

Møller, J E; Søndergaard, E; Poulsen, S H

2001-01-01

To investigate the value of the Doppler-derived myocardial performance index to predict early left-ventricular (LV) dilation and cardiac death after a first acute myocardial infarction (AMI), Doppler echocardiography was performed within 24 h of hospital admission, on day 5, 1 and 3 months after...... AMI in 125 consecutive patients. The index measured on day 1 correlated well with the change in end-diastolic volume index observed from day 1 to 3 months following AMI (r = 0.66, p 0.0001). One-year survival in patients with Doppler index index > or = 0......, we conclude that the Doppler echocardiographic myocardial performance index is a predictor of LV dilation and cardiac death after a first AMI....

Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction

DEFF Research Database (Denmark)

Biering-Sorensen, Tor; Jensen, Jan Skov; Pedersen, Sune H

2016-01-01

deformation in comparison to GLS, conventional echocardiography and clinical information. Method In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI), treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All patients were...... information to clinical and conventional echocardiographic information (Harrell's c-statistics: 0.63 vs. 0.67, p = 0.032). In addition, impaired longitudinal deformation outside the culprit lesion perfusion region was significantly associated with an adverse outcome (p...). Conclusion Regional longitudinal myocardial deformation measures, regardless if determined by TDI or 2DSE, are superior prognosticators to GLS. In addition, impaired longitudinal deformation in the inferior myocardial segment provides prognostic information over and above clinical and conventional...

Sharp inequalities for tangent function with applications

Directory of Open Access Journals (Sweden)

Hui-Lin Lv

2017-05-01

Full Text Available Abstract In the article, we present new bounds for the function e t cot ( t − 1 $e^{t\\cot(t-1}$ on the interval ( 0 , π / 2 $(0, \\pi/2$ and find sharp estimations for the Sine integral and the Catalan constant based on a new monotonicity criterion for the quotient of power series, which refine the Redheffer and Becker-Stark type inequalities for tangent function.

Myocardial imaging with thallium-201: an experimental model for analysis of the true myocardial and background image components

International Nuclear Information System (INIS)

Narahara, K.A.; Hamilton, G.W.; Williams, D.L.; Gould, K.L.

1977-01-01

The true myocardial and background components of a resting thallium-201 myocardial image were determined in an experimental dog model. True background was determined by imaging after the heart had been removed and replaced with a water-filled balloon of equal size and shape. In all studies, the background estimated from the region surrounding the heart exceeded true background activity. Furthermore, the relationship between true myocardial background and that estimated from the pericardiac region was inconsistent. Background estimates based on the activity surrounding the heart were not accurate predictors of true background activity

Acute myocardial infarcts

International Nuclear Information System (INIS)

Just, H.

1988-01-01

Acute myocardial infarction is a major complication of stenosing coronary artery disease and constitutes the most frequent single cause of death. It is caused by thrombotic occlusion of one of the major epicardial coronary arterial branches in most cases. Sudden death due to ventricular fibrillation is responsible for the majority of early fatalities. In 60% of all fatal infarcts, death occurs within 1 h of the onset of pain. The final extension of myocardial necrosis is reached within 2-4 h. An integrated programme has therefore been developed for the supervision and treatment of patients suffering acute coronary attack; it has been shown that it can markedly lower infarct mortality. It includes mobile prehospital care, intensive care treatment in the hospital, and rehabilitative procedures for application during reconvalescence. Early antiarrhythmic treatment and myocardial reperfusion via fibrinolysis are the main therapeutic procedures in the earliest stage. In hospital an operating room and an operating team must be available round the clock for the performance of coronary angiography followed by percutaneous transluminal coronary angioplasty or bypass surgery, which can be safely carried out in the acute stage provided the indications are strictly observed. Mortality and morbidity can be significantly lowered and both life expectancy and quality of life can be remarkably improved. (orig.) [de

Autologous bone marrow concentrate enriched in progenitor cells — An adjuvant in the treatment of acute myocardial infarction

Directory of Open Access Journals (Sweden)

Vinay Sanghi

2016-06-01

Full Text Available Despite advances in revascularization techniques, acute myocardial infarction (AMI still carries significant morbidity and mortality. Over the past decade, the use of regenerative medicine methodologies, and specifically bone marrow derived progenitor cell therapy has been tested in more than 35 Phase I and Phase II clinical studies demonstrating overall safety and measurable clinical benefit, 12–61 months post-treatment as evaluated by improvement in the Left Ventricular Ejection Fraction (LVEF and changes in infarct size post AMI. Recent meta-analysis on the subject highlighted several important parameters that include timing of the cell therapy post AMI, the cell dose, and the baseline LVEF on enrollment. We further postulate that the mythologies and timing for cell handling and delivery including the specific devices are essential for clinical efficacy. Addressing this we have developed a rapid 60 to 90 minute process and integrated system which is carried out in the heart catheter lab, using a combination product (U.S. Food and Drug broadly defined as the combination of co-labeled optimized “cell friendly” devices, effective cell/biological formulation and dose for harvesting, processing, verifying, and delivering an autologous dose of bone marrow progenitor/stem cells via the intracoronary artery proximal to the infarct myocardial region. The methodology has been demonstrated to be safe and feasible for autologous in vivo use and presented by our groups' earlier studies1–3 and most recently used in a Phase Ib critical limb ischemia trial of 17 subjects (NCT01472289 (manuscript under preparation. This is the first case study prior to beginning the AMIRST trial [Acute Myocardial Infarction Rapid Stem cell Therapy], specific to our proprietary combination product kit for acute myocardial infarction, and was completed under the Independent Ethics Committee and Institutional Committee for Stem Cell Research and Therapy approval (TIEC

Quantitation of size of myocardial infarctions by computerized transmission tomography. Comparison with hot-spot and cold-spot radionuclide scans

International Nuclear Information System (INIS)

Gerber, K.H.; Higgins, C.B.

1983-01-01

The current study evaluated the ability to quantitate the volume of myocardial infarctions when they are outlined by intravenously administered contrast media in the myocardial perfusion phase and in the phase of delayed contrast enhancement of the infarct. Quantitation by contrast media was assessed from computerized transmission tomography (CTT) scans of the ex situ heart and compared with quantitation by technetium-99m (/sup 99m/Tc)pyrophosphate (/sup 99m/Tc PYP) and thallium-201 (201Tl) scans of the same ex situ hearts. True volume was defined by histochemical morphometry. CTT during the contrast perfusion phase uniformly underestimated infarct size but had a good correlation with true volume. CTT during enhancement phase correlated closely with true volume (r . 0.98) and most precisely measured true size (y . 1.06 X 0.23). The /sup 99m/Tc PYP scan overestimated infarct volume (predictive overestimation of 6 to 199%) but had a good correlation with true volume. 201Tl underestimated infarct volume but correlated well with true volume. Thus, quantitation of infarct volume from CTT scans performed during either the perfusion or infarct enhancement phase after intravenous contrast media provides a good estimate of true infarct volume. Delineation of the infarct by contrast media in the ex situ heart is more precise during the phase of delayed enhancement of the infarct

Evaluating the effect of PTCA by exercise stress myocardial perfusion imaging

International Nuclear Information System (INIS)

Lin Jinghui

1992-01-01

In this study, 44 patients after successful percutaneous transluminal coronary angioplasty (PTCA) were followed up by exercise stress myocardial perfusion imaging. In 28 patients with myocardial ischemia after PTCA, myocardial imaging of 75.0% patients reverted to normal or approximately normal. In 16 patients of myocardial infarction with ischemia after PTCA, myocardial imaging of only 37.5% patients reverted to normal or approximately normal, significantly less than myocardial ischemia. But the general efficacious incidence was similar in both groups. Most of 77 myocardial segments with complete or obvious redistribution returned to normal imaging after PTCA. During the follow-up coronary artery restenosis occurred in 6 cases, 5 of which were confirmed by coronary arteriography. Restenosis may be discovered as soon as possible, if a patient was reexamined by myocardial imaging 2-6 months after PTCA. The results of this study indicated that myocardial imaging is a noninvasive and reliable method for the assessment of PTCA therapeutic effect and follow up studies

Residual Activity Correction in Quantitative Myocardial Perfusion N-13-Ammonia PET Imaging : A Study in Post-MI Patients

NARCIS (Netherlands)

Markousis-Mavrogenis, George; Juarez-Orozco, Luis Eduardo; Alexanderson, Erick

2017-01-01

Background/Introduction/Aim: Positron emission tomography (PET) is the gold standard for the quantification of myocardial blood flow (MBF). A standard PET scan is acquired in two phases (rest and pharmacological stress). N-13-ammonia is a perfusion radiotracer that may show residual activity, which

Myocardial perfusion imaging, coronary angiography and histological examination in experimental treatment of Ad-HGF for myocardial infarction

International Nuclear Information System (INIS)

Li Jianhua; Feng Jianlin; Cheng Xu; Li Dianfu; Zhang Youfu

2007-01-01

Objective: Gene therapy has drawn a great attention. A swine model of adenovirus hepatocyte growth factor(Ad-HGF) treated myocardial infarction(MI) was utilized, with the effect being assessed by rest myocardial perfusion imaging, coronary angiography and histological examination. Methods: Three groups of MI swine treated with Ad-HGF at low dose [n=5, Ad-HGF 10 8 plague forming unit (PFU)/ site], medium dose(n=5, 4 x 10 8 PFU/site), and high dose (n=5, 5 x 10 9 PFU/site), a control group treated with normal saline(NS, n=5) and a blank control group (n=5) underwent rest myocardial perfusion imaging and coronary angiography before and after treatment. The imaging results were analyzed along with histological findings in each group. Results: The state of myocardial perfusion and Rentrop scores remained unchanged in the blank control and NS groups after treatment. Whereas there was a significant improvement in the two variables in all three groups treated with Ad-HGF. The scores of left circumflex coronary artery (LCX) before and after treated were 7.8 ± 1.3 and 16.4 ± 1.1 (low-dose), 8.2 ± 1.6 and 17.6 ± 0.9 (medium-dose), 8.4 ± 1.5 and 19.0 ± 0.7 (high-dose), respectively. No significant differences were noted among the 3 groups. The number of vessels of NS group was markedly less than that of other groups. Conclusion: Myocardial perfusion imaging seems to be more accurate than coronary angiography and histological examination in evaluating the effects of Ad-HGF on myocardial infarction. (authors)

Meta-Analysis of Stress Myocardial Perfusion Imaging

Science.gov (United States)

2017-06-06

Coronary Disease; Echocardiography; Fractional Flow Reserve, Myocardial; Hemodynamics; Humans; Magnetic Resonance Imaging; Myocardial Perfusion Imaging; Perfusion; Predictive Value of Tests; Single Photon Emission Computed Tomography; Positron Emission Tomography; Multidetector Computed Tomography; Echocardiography, Stress; Coronary Angiography

The endothelial glycocalyx protects against myocardial edema

NARCIS (Netherlands)

van den Berg, Bernard M.; Vink, Hans; Spaan, Jos A. E.

2003-01-01

Myocardial tissue edema attributable to increased microvascular fluid loss contributes to cardiac dysfunction after myocardial ischemia, cardiopulmonary bypass, hypertension, and sepsis. Recent studies suggest that carbohydrate structures on the luminal surface of microvascular endothelium are

Single-step electrochemical method for producing very sharp Au scanning tunneling microscopy tips

International Nuclear Information System (INIS)

Gingery, David; Buehlmann, Philippe

2007-01-01

A single-step electrochemical method for making sharp gold scanning tunneling microscopy tips is described. 3.0M NaCl in 1% perchloric acid is compared to several previously reported etchants. The addition of perchloric acid to sodium chloride solutions drastically shortens etching times and is shown by transmission electron microscopy to produce very sharp tips with a mean radius of curvature of 15 nm

[Study on mechanisms and myocardial protective effect of Qishen Yiqi dropping pills on rats with myocardial infarction].

Science.gov (United States)

Yang, Quan; Cao, Yunshan

2017-06-01

To approach the mechanisms and myocardial protective effect of Qishen Yiqi dropping pills on rats with myocardial infarction. Sixty clean healthy male Sprague-Dawley (SD) rats were randomly divided into sham operation group, model group and observation group (each n = 20). The rat model of acute myocardial infarction (AMI) was established by ligation of left anterior descent (LAD) branch of coronary artery. After modeling, the rats in observation group were given 0.135 g/kg of Qishen Yiqi dropping pills, and sham operation group and model group were administered the same amount of normal saline, once a day for consecutive 28 days. At the end of treatment, the levels of serum inflammatory factors of leukotriene B4 (LTB4), prostaglandin E 2 (PGE 2 ), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were measured by enzyme linked immunosorbent assay (ELISA); the changes of the indexes of hemodynamic [left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), the maximal rate of increase/decrease in left ventricular pressure (±dp/dt max)], the ratio of the heart weight/body weight, and the ratio of the left ventricular weight/heart weight (LVW/HW), the myocardial infarction area, myocardial histopathological changes were observed in the three groups; myocardial tissues inflammatory related factors [the mRNA and protein expressions of cytosolic phospholipase A2 (cPLA2), cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX)], and the expression levels of transforming growth factor-β (TGF-β)/Smads signal transduction pathway related protein (TGF-β1, Smad2/3, Collagen I, Collagen III) and cell apoptosis related factors (Bcl-2, Bax) protein were measured. Compared with the sham operation group, levels of serum inflammatory factors, the index of LVEDP, the ratio of the heart weight/body weight, LVW/HW, myocardial infarction area, the mRNA and protein expression levels of inflammatory factors in myocardium, the expression levels of

Myocardial scintigraphy with I-123 labeled fatty acids

International Nuclear Information System (INIS)

Dudczak, R.

1983-01-01

This study presents experimental and clinical data in the use of I-123 labeled aromatic and aliphatic fatty acids. I-123 p-phenylpentadecanoic acid (p-IPPA) and I-123 heptadecanoic acid (HDA) were applied for myocardial scintigraphy. The feasibility of p-IPPA and HDA for myocardial scintigraphy was substantiated in animal experiments. Clinical studies were performed in patients with coronary artery disease (CAD) and cardiomyopathy (CMP). In CAD the results of fatty acid studies were compared with those of Tl-201. I-123 labeled fatty acids proved to be a useful tool for myocardial scintigraphy. The possibility to evaluate non invasively the myocardial metabolic function in man may add a complementary diagnostic tool in the clinical follow up of patients with heart disease. In CAD studies with I-123 p-IPPA and I-123 HDA might provide a means to assess the degree of myocardial viability and to identify a subgroup of patients who are at increased risk for irreversible myocardial damage. In patients with CMP it is probable that these studies may be used as a means of separating groups of patients with this disease. (Author)

Myocardial ischemia and angina pectoris

International Nuclear Information System (INIS)

Selwyn, A.P.; Fox, K.M.; Jonathan, A.; Lavender, P.; Watson, I.

1981-01-01

Ambulatory monitoring of ST segment changes was performed in 60 patients presenting with angina, positive ECG stress tests and coronary artery disease, 85% of ischemic ECG events were asymptomatic, 37% occurred with no increase in heart rate and 15% of episodes either lasted 20 minutes or more or fluctuated in severity. A controlled pilot study in ten patients showed depression. Radionuclide studies in 50 patients with angina and coronary artery disease have shown that stress (i.e., atrial pacing) produced different patterns of disturbed regional myocardial perfusion related to the patient's exercise capacity and eventually leading to a decrease in regional myocardial perfusion during the ischemic episode. ST segment depression appeared only after the decrease in regional myocardial perfusion. These findings combined with past research suggest that patients with angina and coronary artery disease can suffer frequent asymptomatic disturbances of the regional myocardial perfusion. The frequency of these episodes and the time course for the recovery of the metabolic consequences mean that segments of ventricular myocardium may be constantly abnormal. The relative importance of changes in coronary tone and malfunction of platelets in the diseased coronary tree needs to be examined in clinical research. Pilot studies of antiplatelet agents have shown a significant beneficial effect on episodes of ischemia occurring at night and those occurring without any increase in heart rate. The techniques and observations in these patients with coronary artery disease all suggest that acute transient regional myocardial ischemia is caused by a variety of mechnisms. Further research using objective methods is required to discover the causes of ischemia and to rationalize treatment. (orig./MG) [de

Myocardial infarction false alarm: initial electrocardiogram and cardiac enzymes.

Science.gov (United States)

Gupta, Esha Das; Sakthiswary, Rajalingham

2014-05-01

The objectives of this study were to determine the incidence of a myocardial infarction "false alarm" and evaluate the efficacy of the initial electrocardiogram and cardiac enzymes in diagnosing myocardial infarction in Malaysia. We recruited patients who were admitted with suspected myocardial infarction from June to August 2008. The medical records of these patients were reviewed for the initial electrocardiogram, initial cardiac enzyme levels (creatinine kinase-MB and troponin T), and the final diagnosis upon discharge. The subjects were stratified into 2 groups: true myocardial infarction, and false alarm. 125 patients were enrolled in this study. Following admission and further evaluation, the diagnosis was revised from myocardial infarction to other medical conditions in 48 (38.4%) patients. The sensitivity and specificity of the initial ischemic electrocardiographic changes were 54.5% and 70.8%, respectively. Raised cardiac enzymes had a sensitivity of 44.3% and specificity of 95.8%. A significant proportion of patients in Malaysia are admitted with a false-alarm myocardial infarction. The efficacy of the electrocardiogram in diagnosing myocardial infarction in Malaysia was comparable to the findings of Western studies, but the cardiac enzymes had a much lower sensitivity.

Dynamic CT myocardial perfusion imaging

International Nuclear Information System (INIS)

Caruso, Damiano; Eid, Marwen; Schoepf, U. Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie

2016-01-01

Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

Dynamic CT myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

2016-10-15

Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

Types of Diastolic Dysfunction of the Left Ventricle in Adolescents with Myocardial Pathology

Directory of Open Access Journals (Sweden)

L.F. Bogmat

2014-05-01

Full Text Available In adolescents with myocardial pathology during isometric tests we detected three types of diastolic dysfunction of the left ventricle (LV of the heart, depending on E/A ratio. The most pronounced signs of diastolic filling disorders were detected in the third group of patients, as evidenced: by a tendency to increase isovolumic relaxation time, a significant increase of slowing down time of the first phase of left ventricular filling, reduced LV filling rate both in the first phase of the passive filling and the second phase of active LV filling, increasing E/A ratio of more than 2, significant dilation of the left atrium, as well as positive increase in diastolic reserve that confirms deeper diastolic dysfunction in these adolescents compared with other subgroups.

Herbivores Enforce Sharp Boundaries Between Terrestrial and Aquatic Ecosystems

NARCIS (Netherlands)

Sarneel, Judith M.; Huig, N.; Veen, G. F.; Rip, W.; Bakker, E. S.

2014-01-01

The transitions between ecosystems (ecotones) are often biodiversity hotspots, but we know little about the forces that shape them. Today, often sharp boundaries with low diversity are found between terrestrial and aquatic ecosystems. This has been attributed to environmental factors that hamper

Quasi-phases and pseudo-transitions in one-dimensional models with nearest neighbor interactions

Science.gov (United States)

de Souza, S. M.; Rojas, Onofre

2018-01-01

There are some particular one-dimensional models, such as the Ising-Heisenberg spin models with a variety of chain structures, which exhibit unexpected behaviors quite similar to the first and second order phase transition, which could be confused naively with an authentic phase transition. Through the analysis of the first derivative of free energy, such as entropy, magnetization, and internal energy, a "sudden" jump that closely resembles a first-order phase transition at finite temperature occurs. However, by analyzing the second derivative of free energy, such as specific heat and magnetic susceptibility at finite temperature, it behaves quite similarly to a second-order phase transition exhibiting an astonishingly sharp and fine peak. The correlation length also confirms the evidence of this pseudo-transition temperature, where a sharp peak occurs at the pseudo-critical temperature. We also present the necessary conditions for the emergence of these quasi-phases and pseudo-transitions.

Conservative sharp debridement: the professional and legal issues.

Science.gov (United States)

Ashworth, Jenny; Chivers, Marc

2002-06-01

In recent years there has been much debate over the use of conservative sharp debridement in the treatment of certain wound types. Here it is discussed in relation to increasing the speed of wound healing in slow-to-heal wounds. The authors examine education and skill competence in relation to the professional's duty of care to patients with wounds.

Sharp Bounds for Symmetric and Asymmetric Diophantine Approximation

Institute of Scientific and Technical Information of China (English)

Cornelis KRAAIKAMP; Ionica SMEETS

2011-01-01

In 2004,Tong found bounds for the approximation quality of a regular continued fraction convergent to a rational number,expressed in bounds for both the previous and next approximation.The authors sharpen his results with a geometric method and give both sharp upper and lower bounds.The asymptotic frequencies that these bounds occur are also calculated.

Sevoflurane postconditioning improves myocardial mitochondrial respiratory function and reduces myocardial ischemia-reperfusion injury by up-regulating HIF-1.

Science.gov (United States)

Yang, Long; Xie, Peng; Wu, Jianjiang; Yu, Jin; Yu, Tian; Wang, Haiying; Wang, Jiang; Xia, Zhengyuan; Zheng, Hong

2016-01-01

Sevoflurane postconditioning (SPostC) can exert myocardial protective effects similar to ischemic preconditioning. However, the exact myocardial protection mechanism by SPostC is unclear. Studies indicate that hypoxia-inducible factor-1 (HIF-1) maintains cellular respiration homeostasis by regulating mitochondrial respiratory chain enzyme activity under hypoxic conditions. This study investigated whether SPostC could regulate the expression of myocardial HIF-1α and to improve mitochondrial respiratory function, thereby relieving myocardial ischemia-reperfusion injury in rats. The myocardial ischemia-reperfusion rat model was established using the Langendorff isolated heart perfusion apparatus. Additionally, postconditioning was performed using sevoflurane alone or in combination with the HIF-1α inhibitor 2-methoxyestradiol (2ME2). The changes in hemodynamic parameters, HIF-1α protein expression levels, mitochondrial respiratory function and enzyme activity, mitochondrial reactive oxygen species (ROS) production rates, and mitochondrial ultrastructure were measured or observed. Compared to the ischemia-reperfusion (I/R) group, HIF-1α expression in the SPostC group was significantly up-regulated. Additionally, cardiac function indicators, mitochondrial state 3 respiratory rate, respiratory control ratio (RCR), cytochrome C oxidase (C c O), NADH oxidase (NADHO), and succinate oxidase (SUCO) activities, mitochondrial ROS production rate, and mitochondrial ultrastructure were significantly better than those in the I/R group. However, these advantages were completely reversed by the HIF-1α specific inhibitor 2ME2 ( P <0.05). The myocardial protective function of SPostC might be associated with the improvement of mitochondrial respiratory function after up-regulation of HIF-1α expression.

Myocardial ischemia in hypertrophic cardiomyopathy; Isquemia miocardica na cardiomiopatia hipertrofica

Energy Technology Data Exchange (ETDEWEB)

Lima Filho, Moyses de Oliveira; Figueiredo, Geraldo L.; Simoes, Marcus V.; Pyntia, Antonio O.; Marin Neto, Jose Antonio [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Div. de Cardiologia

2000-08-01

Myocardial ischemia in hypertrophic cardiomyopathy is multifactorial and explains the occurrence of angina, in about 50% of patients. The pathophysiology of myocardial ischemia may be explained by the increase of the ventricular mass and relative paucity of the coronary microcirculation; the elevated ventricular filling pressures and myocardial stiffness causing a compression of the coronary microvessels; the impaired coronary vasodilator flow reserve caused by anatomic and functional abnormalities; and the systolic compression of epicardial vessel (myocardial bridges). Myocardial ischemia must be investigated by perfusion scintigraphic methods since its presence influences the prognosis and has relevant clinical implications for management of patients. Patients with hypertrophic cardiomyopathy and documented myocardial ischemia usually need to undergo invasive coronary angiography to exclude the presence of concomitant atherosclerotic coronary disease. (author)

Acute myocardial infarction

International Nuclear Information System (INIS)

RISCHPLER, Christoph

2016-01-01

Inflammatory processes after myocardial infarction have gained major interest in recent cardiovascular research. It is believed that not only the degree of cell recruitment to the heart plays a pivotal role in the quality of wound healing after myocardial infarction, but also the balance between different types or even subtypes of cells. It is also this balance which is thought to control key processes in tissue repair, such as apoptosis and neoangiogenesis. In this paper, we aim to review imaging strategies (with a special focus on nuclear molecular imaging strategies) that target cells and processes involved in postischemic inflammation and that have a high potential to be translated into clinic or that are already being used and evaluated in humans.

Cardiac index after acute ST-segment elevation myocardial infarction measured with phase-contrast cardiac magnetic resonance imaging

International Nuclear Information System (INIS)

Klug, Gert; Reinstadler, Sebastian Johannes; Feistritzer, Hans-Josef; Schwaiger, Johannes P.; Reindl, Martin; Mair, Johannes; Mueller, Silvana; Franz, Wolfgang-Michael; Metzler, Bernhard; Kremser, Christian; Mayr, Agnes

2016-01-01

Phase-contrast CMR (PC-CMR) might provide a fast and robust non-invasive determination of left ventricular function in patients after ST-segment elevation myocardial infarction (STEMI). Cine sequences in the left-ventricular (LV) short-axis and free-breathing, retrospectively gated PC-CMR were performed in 90 patients with first acute STEMI and 15 healthy volunteers. Inter- and intra-observer agreement was determined. The correlations of clinical variables age, gender, ejection fraction, NT pro-brain natriuretic peptide [NT-proBNP] with cardiac index (CI) were calculated. For CI, there was a strong agreement of cine CMR with PC-CMR in healthy volunteers (r: 0.82, mean difference: -0.14 l/min/m 2 , error ± 23 %). Agreement was lower in STEMI patients (r: 0.61, mean difference: -0.17 l/min/m 2 , error ± 32 %). In STEMI patients, CI measured with PC-CMR showed lower intra-observer (1 % vs. 9 %) and similar inter-observer variability (9 % vs. 12 %) compared to cine CMR. CI was significantly correlated with age, ejection fraction and NT-proBNP values in STEMI patients. The agreement of PC-CMR and cine CMR for the determination of CI is lower in STEMI patients than in healthy volunteers. After acute STEMI, CI measured with PC-CMR decreases with age, LV ejection fraction and higher NT-proBNP. (orig.)

Evaluation of myocardial sympathetic nerve function in patients with mitral valve prolapse using iodine-123-metaiodobenzylguanidine myocardial scintigraphy

International Nuclear Information System (INIS)

Kishi, Fumiko; Nomura, Masahiro; Yukinaka, Michiko

1996-01-01

Mitral valve prolapse (MVP) is closely related to myocardial sympathetic nerve function. This study evaluated the presence of impaired myocardial sympathetic nerve function by Iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in nine patients with MVP. For comparison, 15 healthy subjects without heart disease were investigated (control group). Single photon emission computed tomography (SPECT) and anterior planar myocardial scintigraphy were performed 15 min (initial images) and 3 hours (delayed images) after injection of MIBG (111 MBq). The location and degrees of reduced tracer uptake were evaluated. Myocardial MIBG uptake was quantified by uptake ratio of the heart (H) to upper mediastinum (M) on the anterior planar images (H/M). Percentage washout of MIBG in nine sectors of all oblique slices along the short-axis was calculated. The washout rates were higher at the inferoposterior and septal segments in patients with anterior leaflet prolapse, and at inferoposterior and lateral segments in patients with posterior leaflet prolapse. The bull's eye map showed increased washout rate in the apical and posteroseptal basal segments. There was no significant difference in the H/M ratio between MVP patients and the control group. These results indicate that MIBG can be used to evaluate localized myocardial sympathetic nerve function in MVP. (author)

Evaluation of initial uptake and redistribution on stress thallium-201 myocardial perfusion images in patients with myocardial infarction

International Nuclear Information System (INIS)

Watanabe, Yoshihiko; Tonooka, Ichiroh; Kanaya, Tohru; Tsuiki, Kai; Yasui, Shouji.

1984-01-01

Stress thallium-201 myocardial perfusion imaging was performed on 29 patients with previous myocardial infarction and 29 patients with angina pectoris at exercise to evaluate thallium-201 kinetics in ischemic heart disease. Four views of thallium-201 images (right anterior oblique, antero-posterior, left anterior oblique and left lateral views) were obtained at 5 min after treadmill exercise with administration of 2 mCi of thallium-201 chloride (initial image) and at 3 hours later (delayed image). Myocardial images were divided into 6 segments (anterior, lateral, inferior, posterior, apical and septal segments) and initial uptake (IU) and redistribution index (RDI, the ratio of the maximal washout rate to a washout rate in each segment) were calculated in order to assess the relations of thallium-201 kinetics to wall motion abnormality and coronary artery stenosis. In myocardial infarction, IU and RDI were decreased in proportion to the severity of wall motion abnormality and coronary artery stenosis. Contrarily, in angina pectoris, IU was decreased but RDI was increased proportionally to the severity of coronary arterial stenosis. In conclusion, IU and redistribution of thallium-201 were affected essentially by both the grade of coronary arterial stenosis and the amount of residual viable heart muscle in patients with ischemic myocardial disease. (author)

Myocardial myoglobin release after acute myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Robinson, P S; Saltissi, S; Coltart, D J; Croft, D N [Saint Thomas' Hospital, London (UK)

1980-03-01

The magnitude and time course of myoglobin release from the myocardium following infarction was assessed by radioimmunoassay. The assay showed acceptable precision over a working range from 50 to 750 ng cm/sup -3/, provided careful control of the assay temperature was maintained. The use of this radioimmunoassay as an early diagnostic test for infarction and as a potential measure of the extent of necrosis is considered and comparison made with the release of CK-MB, the myocardial specific isoenzyme of creatine kinase. Of the twenty patients studied with myocardial infarction, all had elevated levels of serum myoglobin including those admitted within 3 hours of the onset of pain. In contrast, CK-MB was not detected in the serum within 5 hours of the onset of pain. Peak serum levels of myoglobin (mean 852 +- 365 ng cm/sup -3/) and CK-MB (mean 71 +- 25 mIU cm/sup -3/) were detected at 8-16 hours and 20-24 hours respectively after the onset of pain. A comparison of peak serum levels of myoglobin and CK-MB showed a good correlation (r = 0.84).

A relative quantitative assessment of myocardial perfusion by first-pass technique: animal study

Science.gov (United States)

Chen, Jun; Zhang, Zhang; Yu, Xuefang; Zhou, Kenneth J.

2015-03-01

The purpose of this study is to quantitatively assess the myocardial perfusion by first-pass technique in swine model. Numerous techniques based on the analysis of Computed Tomography (CT) Hounsfield Unit (HU) density have emerged. Although these methods proposed to be able to assess haemodynamically significant coronary artery stenosis, their limitations are noticed. There are still needs to develop some new techniques. Experiments were performed upon five (5) closed-chest swine. Balloon catheters were placed into the coronary artery to simulate different degrees of luminal stenosis. Myocardial Blood Flow (MBF) was measured using color microsphere technique. Fractional Flow Reserve (FFR) was measured using pressure wire. CT examinations were performed twice during First-pass phase under adenosine-stress condition. CT HU Density (HUDCT) and CT HU Density Ratio (HUDRCT) were calculated using the acquired CT images. Our study presents that HUDRCT shows a good (y=0.07245+0.09963x, r2=0.898) correlation with MBF and FFR. In receiver operating characteristic (ROC) curve analyses, HUDRCT provides excellent diagnostic performance for the detection of significant ischemia during adenosine-stress as defined by FFR indicated by the value of Area Under the Curve (AUC) of 0.927. HUDRCT has the potential to be developed as a useful indicator of quantitative assessment of myocardial perfusion.

Driving Skills Training for Older Adults: An Assessment of DriveSharp.

Science.gov (United States)

Johnston, Katherine A; Borkenhagen, David; Scialfa, Charles T

2015-12-01

RÉSUMÉ Les procédures de formation cognitive informatique visent à augmenter la sécurité en améliorant les compétences relatives à la conduite, comme la vitesse-de-traitement et le Useful Field of View. L'étude actuelle a évalué l'efficacité du DriveSharp dans la formation des conducteurs âgés dans un cadre de classe réaliste. Les participants (n = 24) ont assisté à 10 heures de cours de DriveSharp pendant 5 semaines. Les séances pré- et post-test ont evalués améliorations sur un essai dynamique de la perception du risque, Trails A et Trails B. Un groupe de contrôle (n = 18) a terminé seulement les séances pré- et post-test. En classe, les temps de formation étaient plus bas que prévus. L'amélioration des participants aux jeux ont stabilisée après la première évaluation, et le groupe de DriveSharp n'a pas démontré une amélioration significative des performances sur les tests, par rapport au groupe de contrôle. Parmi plusieurs questions relatives à la facilité d'utilisation, les plus problématiques étaient le malentendudes objectifs de la tâche et la différence entre la formation et l'évaluation. Il y a plusieurs implications pour ceux qui utilisent DriveSharp pour améliorer la sécurité des conducteurs âgés.

Exercise-induced ST-segment depression and myocardial ischemia in patients with hypertrophic cardiomyopathy. Myocardial scintigraphic study

International Nuclear Information System (INIS)

Miyai, Nobuyuki; Kawasaki, Tatsuya; Taniguchi, Takuya; Kamitani, Tadaaki; Kawasaki, Shingo; Sugihara, Hiroki

2005-01-01

Patients with hypertrophic cardiomyopathy (HCM) sometimes develop myocardial ischemia during exercise in the absence of coronary lesions. The relationship between myocardial ischemia and ST-segment depression was investigated during exercise testing in patients with HCM. Regional hypoperfusion and/or transient left ventricular cavity dilation, a parameter of subendocardial hypoperfusion, were assessed on exercise 99 m Tc-tetrofosmin myocardial scintigraphy in 42 patients with non-obstructive HCM. The scintigraphic results were further correlated with the ST-segment responses to exercise. Regional hypoperfusion or transient left ventricular cavity dilation were observed in 19 (45%) or 16 (38%) patients with HCM, respectively. The incidence of ST-segment depression ≥0.1 mV during exercise testing was similar in HCM patients with regional hypoperfusion, with transient left ventricular cavity dilation, and without hypoperfusion (42%, 38%, 38%, p=0.95). Furthermore, exercise-induced ST-segment depression ≥0.1 mV occurred similarly irrespective of symptoms, exercise tolerance, the degree or the site of hypertrophy, or the presence or absence of resting ST-segment depression. ST-segment depression during exercise testing was common in patients with HCM, but seems to be an unreliable marker of myocardial ischemia as assessed by exercise scintigraphy. (author)

Prevalence of myocardial ischaemia as assessed with myocardial perfusion scintigraphy in patients with diabetes mellitus type 2 and mild anginal symptoms

International Nuclear Information System (INIS)

Wiersma, Jacobijne J.; Trip, Mieke D.; Piek, Jan J.; Tijssen, Jan G.P.; Verberne, Hein J.; Eck-Smit, Berthe L.F. van; Holt, Wik L. ten

2006-01-01

To determine the prevalence and predictors of reversible myocardial perfusion defects, indicative of myocardial ischaemia, in patients with mild, stable anginal complaints [Canadian Cardiovascular Society classification (CCS) I-II/IV] and diabetes mellitus type 2 (T2DM). A total of 329 patients with T2DM and stable, mild anginal symptoms (CCS I-II/IV) underwent myocardial perfusion scintigraphy. Perfusion images were assessed using a five-point (semi)-quantitative scoring system according to a 17-segment myocardial model. One-hundred and fifty-six (47%) patients showed reversible myocardial perfusion defects defined as a summed difference score of ≥3. Male gender [odds ratio (OR) 2.28, 95% CI 1.4-3.71, p=0.001], previous myocardial infarction (MI) without revascularisation (OR 3.04, 95% CI 1.28-7.24, p=0.01), and the use of two or more classes of anti-anginal medication (OR 2.36, 95% CI 1.48-3.76, p<0.001) were independent predictors for the presence of reversible defects. By contrast, lipid-lowering therapy reduced the possibility of reversible perfusion defects (OR 0.56, 95% CI 0.33-0.95, p=0.03). Approximately half of the patients with mild, stable angina pectoris and T2DM showed evidence of myocardial ischaemia. Male gender, previous MI and the use of anti-anginal medication were positive predictors and lipid-lowering therapy was a negative predictor for the results of the scintigraphic stress test. (orig.)

Prevalence of myocardial ischaemia as assessed with myocardial perfusion scintigraphy in patients with diabetes mellitus type 2 and mild anginal symptoms

Energy Technology Data Exchange (ETDEWEB)

Wiersma, Jacobijne J.; Trip, Mieke D.; Piek, Jan J.; Tijssen, Jan G.P. [Academic Medical Center, Department of Cardiology, Amsterdam (Netherlands); Verberne, Hein J.; Eck-Smit, Berthe L.F. van [Academic Medical Center Amsterdam, Department of Nuclear Medicine, Amsterdam (Netherlands); Holt, Wik L. ten [Amstelland Hospital, Department of Cardiology, Amstelveen (Netherlands)

2006-12-15

To determine the prevalence and predictors of reversible myocardial perfusion defects, indicative of myocardial ischaemia, in patients with mild, stable anginal complaints [Canadian Cardiovascular Society classification (CCS) I-II/IV] and diabetes mellitus type 2 (T2DM). A total of 329 patients with T2DM and stable, mild anginal symptoms (CCS I-II/IV) underwent myocardial perfusion scintigraphy. Perfusion images were assessed using a five-point (semi)-quantitative scoring system according to a 17-segment myocardial model. One-hundred and fifty-six (47%) patients showed reversible myocardial perfusion defects defined as a summed difference score of {>=}3. Male gender [odds ratio (OR) 2.28, 95% CI 1.4-3.71, p=0.001], previous myocardial infarction (MI) without revascularisation (OR 3.04, 95% CI 1.28-7.24, p=0.01), and the use of two or more classes of anti-anginal medication (OR 2.36, 95% CI 1.48-3.76, p<0.001) were independent predictors for the presence of reversible defects. By contrast, lipid-lowering therapy reduced the possibility of reversible perfusion defects (OR 0.56, 95% CI 0.33-0.95, p=0.03). Approximately half of the patients with mild, stable angina pectoris and T2DM showed evidence of myocardial ischaemia. Male gender, previous MI and the use of anti-anginal medication were positive predictors and lipid-lowering therapy was a negative predictor for the results of the scintigraphic stress test. (orig.)

Comparison of initial and delayed myocardial imaging with beta-methyl-p-[123I]-iodophenylpentadecanoic acid in acute myocardial infarction

International Nuclear Information System (INIS)

Naruse, Hitoshi; Yoshimura, Noriko; Yamamoto, Juro; Morita, Masato; Fukutake, Naoshige; Ohyanagi, Mitsumasa; Iwasaki, Tadaaki; Fukuchi, Minoru

1994-01-01

Myocardial imaging using β-methyl-p-[ 123 I]-iodophenylpentadecanoic acid (BMIPP) of 15 patients with acute myocardial infarction was performed to assess 'fill-in' and 'washout' defects in the delayed myocardial image. The initial and delayed images were evaluated by a visual and quantitative washout rate method. Visual judgement found 8/180 (4%) segments showed 'fill-in' defects, and 24/180 segments (13%) showed 'washout' defects. There was no relationship between days from onset to the study and the frequency of fill-in and washout defects. The mean washout rate in the segments with 'fill-in' defects was 9.0±16.6%, and that of 'washout' defects was 24.9±18.1% which was significantly higher than in controls (8.7±15.4%, p<0.05). There was no correlation between mean washout rate and total blood lipids, total cholesterol, triglyceride and HDL-cholesterol. Therefore, neither time from onset nor blood lipids level was related to changes from the initial image to the delayed image. These changes may be due to relative (false) findings due to changes in circumference, and may be based on myocardial characteristics after myocardial infarction and/or reperfusion. (author)

[Comparison of initial and delayed myocardial imaging with beta-methyl-p-[123I]-iodophenylpentadecanoic acid in acute myocardial infarction].

Science.gov (United States)

Naruse, H; Yoshimura, N; Yamamoto, J; Morita, M; Fukutake, N; Ohyanagi, M; Iwasaki, T; Fukuchi, M

1994-01-01

Myocardial imaging using beta-methyl-p-[123I]-iodophenylpentadecanoic acid (BMIPP) of 15 patients with acute myocardial infarction was performed to assess "fill-in" and "washout" defects in the delayed myocardial image. The initial and delayed images were evaluated by a visual and quantitative washout rate method. Visual judgement found 8/180 (4%) segments showed "fill-in" defects, and 24/180 segments (13%) showed "washout" defects. There was no relationship between days from onset to the study and the frequency of fill-in and washout defects. The mean washout rate in the segments with "fill-in" defects was 9.0 +/- 16.6%, and that of "washout" defects was 24.9 +/- 18.1% which was significantly higher than in controls (8.7 +/- 15.4%, p < 0.05). There was no correlation between mean washout rate and total blood lipids, total cholesterol, triglyceride and HDL-cholesterol. Therefore, neither time from onset nor blood lipids level was related to changes from the initial image to the delayed image. These changes may be due to relative (false) findings due to changes in circumference, and may be based on myocardial characteristics after myocardial infarction and/or reperfusion.

Effect of Kaempferol Pretreatment on Myocardial Injury in Rats.

Science.gov (United States)

Vishwakarma, Anamika; Singh, Thakur Uttam; Rungsung, Soya; Kumar, Tarun; Kandasamy, Arunvikram; Parida, Subhashree; Lingaraju, Madhu Cholenahalli; Kumar, Ajay; Kumar, Asok; Kumar, Dinesh

2018-01-20

The present study was undertaken to evaluate the effect of kaempferol in isoprenaline (ISP)-induced myocardial injury in rats. ISP was administered subcutaneously for two subsequent days to induce myocardial injury. Assessment of myocardial injury was done by estimation of hemodynamic functions, myocardial infarcted area, cardiac injury markers, lipid profile, oxidative stress, pro-inflammatory cytokines and histopathology of heart and liver. Rats pretreated with kaempferol showed reduction in the myocardial infarcted area and heart rate. However, no improvement was observed in change in body weight, mean arterial, systolic and diastolic blood pressure. Kaempferol showed significant decrease in serum LDH, CK-MB, troponin-I and lipid profile. However, highest dose of kaempferol did not reduce the serum triglyceride level. Further, antioxidant enzymes, SOD and catalase, were also higher. However, reduced glutathione, serum SGOT and creatinine did not show any improvement. Kaempferol showed reduction in MDA level. Kaempferol at highest dose showed reduction in pro-MMP-2 expression and MMP-9 level. mRNA expression level of TNF-α was not different in kaempferol-pretreated myocardial injured rats with ISP-alone group. Pretreatment with kaempferol at highest dose showed mild mononuclear infiltration and degenerative changes in heart tissue section of myocardial injured rats. Rats pretreated with kaempferol at higher concentration showed normal cordlike arrangement of hepatocytes with moderate swelling of hepatocytes (vacuolar degeneration) around the central vein. Study suggests that kaempferol attenuated lipid profile, infarcted area and oxidative stress in ISP-induced myocardial injury in rats.

Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

Energy Technology Data Exchange (ETDEWEB)

Som, P.; Wang, G.J. [Brookhaven National Lab., Upton, NY (United States); Oster, Z.H. [State Univ. of New York, Stony Brook, NY (United States); Knapp, F.F. Jr. [Oak Ridge National Lab., TN (United States); Yonekura, Y. [Kyoto Univ. (Japan). Faculty of Medicine; Fujibayashi, Y. [Kyoto Univ. (Japan). Hospital; Yamamoto, K. [Fukui Univ. (Japan). Medical School; Kubota, K. [Tohoku Univ., Sendai (Japan)

1992-12-31

Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.

Myocardial uptake of cocaine and effects of cocaine on myocardial substrate utilization and perfusion in hypertensive rats

Energy Technology Data Exchange (ETDEWEB)

Som, P.; Wang, G.J. (Brookhaven National Lab., Upton, NY (United States)); Oster, Z.H. (State Univ. of New York, Stony Brook, NY (United States)); Knapp, F.F. Jr. (Oak Ridge National Lab., TN (United States)); Yonekura, Y. (Kyoto Univ. (Japan). Faculty of Medicine); Fujibayashi, Y. (Kyoto Univ. (Japan). Hospital); Yamamoto, K. (Fukui Univ. (Japan). Medical School); Kubota, K. (Tohoku Univ., Sendai

1992-01-01

Cocaine abuse is a problem causing world-wide concern and the number of deaths following cocaine use is increasing. Cardiovascular complications following cocaine include severe tachyarrythmias, pulmonary edema, myocardial infarction, and acute renal failure, which are major problems confronting emergency facilities. While the studies of cocaine effects on the brain have been given the most attention, it is clear that the effects of cocaine on the cardiovascular system are of great importance, given the increasing number of reports on sudden death and myocardial infarctions in young adults related to cocaine use. The precise mechanisms of cardiotoxic actions of cocaine are unclear. We investigated the whole-body distribution of C-14-labeled cocaine to determine the cocaine-binding sites, including blocking experiments to determine the nature of regional binding sites, and differential response of the normal vs. diseased heart (hypertensive cardiomyopathy) in an animal model to mimic a potentially high risk population. We investigated the acute effects of cocaine on myocardial metabolism using two myocardial energy substrate analogs, fatty acid and glucose with comparison with regional perfusion.

Technetium-99m-pyrophosphate myocardial imaging in unstable angina

International Nuclear Information System (INIS)

Willerson, J.T.; Parkey, R.W.; Lewis, S.E.; Buja, L.M.; Bonte, F.J.

1980-01-01

The authors have found that approximately one third of patients with the syndrome of unstable angina pectoris have abnormal 99mTc-pyrophosphate myocardial scintigrams even in the absence of abnormal enzymes and electrocardiographic confirmation of the presence of acute myocardial necrosis. Thus, 99mTc-pyrophosphate myocardial imaging technique appears to represent a sensitive means to detect acute multicellular injury associated with the clinical syndrome of unstable angina pectoris even when cardiac enzymes are normal and the electrocardiogram does not definitively document the presence of acute myocardial necrosis. (Auth.)

Myocardial infarction after near drowning.

Science.gov (United States)

Chen, Li-Bang; Lai, Yen-Chun; Chen, Chang-Chih; Chang, Wen-Han; Su, Yu-Jang

2008-06-01

During summer, near drowning is a common accident in Taiwan. It may lead to multiple organ damages in cases where severe hypothermia and hypoxemia occur. We present a case of myocardial infarction after near drowning. The patient was sent to our ED by the emergency medical services called by the witness. On arrival to our ED, hypothermia and hypoxemia overcame him. Endotracheal intubation and warm intravenous fluid were applied at once owing to drowsy consciousness, respiratory distress, and hypothermia. Electrocardiogram showed diffuse ST-segment elevation over the precordial leads V2-V6. The initial level of cardiac enzymes was within normal limit but elevated in troponin I on the second day after hospitalization. We presumed that the possibility of myocardial infarction resulted from near drowning-related hypoxemia. To our knowledge, this is the first case describing myocardial injury with electrocardiogram changes after near drowning.

Acute myocardial infarction in a young adult with myocardial bridging and normal coronary arteries

Directory of Open Access Journals (Sweden)

Moris Chansky

2004-09-01

Full Text Available The authors present a case of a young adult with acute myocardialinfarction, attended at the Emergency Department of HospitalIsraelita Albert Einstein. Acute myocardial infarction caused bymyocardial bridge (intramyocardial tunneled coronary artery is arare clinical entity. The finding of this condition in patients withnormal arteries (non-obstructed vessels is uncommon; it isusually associated with extracardiac triggering factors. The casereported presented an acute myocardial infarction caused by amyocardial bridge as demonstrated in the clinical picture, ECGprogression, enzyme pattern (troponin, CKMB, TGO and LD andventriculography.

Myocardial imaging with cesium-130

International Nuclear Information System (INIS)

Harper, P.V.; Resnekov, L.; Stark, V.; Odeh, N.

1984-01-01

Recently comparative studies using nitrogen-13 ammonia and cesium-130 have shown strikingly different myocardial localization patterns in the same subjects with ischemic heart disease. Initial localization of ammonia, an avidly extracted agent, reflects the perfusion pattern in viable myocardial tissue. The myocardial localization of cesium ion, taking place more slowly over 15 to 20 minutes, is apparently much less flow dependent, causing uptake defects shown with ammonia to be largely filled in. Cesium thus appears to provide information on the extent of the viable myocardial mass, apart from perfusion. Cesium-130 (t1/2 30 m) decays by positron emission and electron capture. The whole body radiation absorbed dose, assuming uniform distribution, is 24 mrad/mCi. While abundant production of Cs-130 results from proton bombardment of natural xenon [Xe-130(rho,n)Cs-130] at 15 MeV, small amounts of Cs-129, -131, and -132 are also produced, and enriched Xe-130 is not available. Alternatively almost completely uncontaminated Cs-130 is available by alpha bombardment of natural I-127. Anhydrous sodium iodide is dissolved in acetone and a thin layer (≅20 mg per centimeter squared) is evaporated onto the gold plated tip of the internal target backing which is oscillated vertically to spread out the area upon which the beam is incident. The target surface is inclined 2.5 degrees to the beam giving a power density of about 400 watts per centimeter squared at 100μA which is adequately handled by water cooling. A 30-minute bombardment yields 4 to 5 mCi of Cs-130 which is dissolved directly from the target. This approach appears to offer a new and helpful method for evaluating ischemic heart disease by permitting evaluation of viable myocardial mass

Radioiodinated tracers for myocardial imaging

International Nuclear Information System (INIS)

Kulkarni, P.V.; Corbett, J.R.

1990-01-01

Recent advances in the efficient production of high purity radioiodine (123I) and new efficient radiolabeling techniques have allowed the development of new classes of cardiovascular radiopharmaceuticals. These include 123I-labeled fatty acids to assess myocardial metabolism, 123I-metaiodobenzylguanidine (MIBG) for myocardial neuronal activity, labeled monoclonal antibodies for myocardial necrosis, and labeled lipoproteins for receptor concentration. 123I-labeled fatty acids and MIBG are under clinical investigation with encouraging results. 123I- and 111In-labeled fragments of monoclonal antibodies to myosin have been used for imaging myocardial necrosis in humans. The development of radiotracers for imaging of cholinergic and adrenergic receptors is still in the experimental stage. Recent advances in imaging instrumentation and radiopharmaceuticals have resulted in cardiac imaging applications beyond blood pool ventriculography, perfusion, and infarct-avid imaging. Developments of radioiodine (123I)-labeled agents promise to play an important role in the assessment of myocardial metabolism, neuronal activity, and receptor concentration. The chemistry of iodine is well defined compared with that of 99mTc; therefore, iodine isotopes are well suited for labeling biologically important molecules. Among the iodine isotopes, 123I has nearly ideal nuclear properties for nuclear medical applications with a 13.3-hour half-life (T1/2) and 159 keV gamma emission (83%). Despite the nearly ideal chemical and nuclear properties of 123I, the widespread application of 123I-based radiopharmaceuticals in clinical practice has been limited by high production costs (123I is produced in a cyclotron), relatively limited availability, and the presence of undesirable radionuclidic impurities (124I, T1/2 = 4.2 days; 125I, T1/2 = 60 days; 126I, T1/2 = 13.1 days). 77 references

Cardioprotection against experimental myocardial ischemic injury using cornin

Directory of Open Access Journals (Sweden)

Y. Xu

2016-01-01

Full Text Available Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt.

Myocardial strains from 3D displacement encoded magnetic resonance imaging

Directory of Open Access Journals (Sweden)

Kindberg Katarina

2012-04-01

Full Text Available Abstract Background The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE, make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. Methods We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. Results The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Conclusions Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

Prognostic relevance of PCI-related myocardial infarction

NARCIS (Netherlands)

Woudstra, Pier; Grundeken, Maik J.; van de Hoef, Tim P.; Wallentin, Lars; Fox, Keith A.; de Winter, Robbert J.; Damman, Peter

2013-01-01

Procedure-related myocardial infarction (pMI) is directly associated with a coronary revascularization procedure, such as percutaneous coronary intervention (PCI) or CABG surgery. In contrast to spontaneous myocardial infarction (MI), the prognostic relevance of pMI is the subject of ongoing debate.

52 Genetic Loci Influencing Myocardial Mass

DEFF Research Database (Denmark)

van der Harst, Pim; van Setten, Jessica; Verweij, Niek

2016-01-01

BACKGROUND: Myocardial mass is a key determinant of cardiac muscle function and hypertrophy. Myocardial depolarization leading to cardiac muscle contraction is reflected by the amplitude and duration of the QRS complex on the electrocardiogram (ECG). Abnormal QRS amplitude or duration reflect cha...

The end of the unique myocardial band

DEFF Research Database (Denmark)

MacIver, David H; Partridge, John B; Agger, Peter

2018-01-01

Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour th...

A rare case of a sharp foreign body on the vocal cord

Directory of Open Access Journals (Sweden)

Khairunnisak Misron

2017-08-01

Full Text Available A foreign body (FB in the upper aerodigestive tract is a common clinical problem that presents as as acute emergency. Sharp FB, such as fish bone or chicken bone, commonly lodges in the tonsil, base of tongue, vallecula or pyriform fossa. Dislodgement of a FB into the laryngopharynx is very rare and specifically onto the vocal cord is extremely uncommon. This case report illustrates a rare case of a sharp FB that was dislodged into the airway and stuck on to the right vocal cord, which was removed under local anaesthesia.

Delayed ventricular septal rupture complicating acute inferior wall myocardial infarction

OpenAIRE

Cho, Jae Hyung; Sattiraju, Srinivasan; Mehta, Sanjay; Missov, Emil

2013-01-01

Background Ventricular septal rupture is a potentially fatal complication of acute myocardial infarction. Its incidence has declined with modern reperfusion therapy. In the era of percutaneous coronary interventions, it occurs a median of 18?24?hours after myocardial infarction and is most commonly associated with anterior myocardial infarction. We present a case of delayed ventricular septal rupture complicating acute inferior wall myocardial infarction. Case presentation A 53-year-old Cauca...

Usefulness of BMIPP SPECT to evaluate myocardial viability, contractile reserve and coronary stenotic progression after reperfusion in acute myocardial infarction

International Nuclear Information System (INIS)

Katsunuma, Eita; Kurokawa, Shingo; Takahashi, Motoi; Fukuda, Naoto; Kurosawa, Toshiro; Izumi, Tohru

2001-01-01

Using combined 123 I-BMIPP (BMIPP), 201 Tl (Tl) and 99m Tc-PYP (PYP) myocardial SPECT imaging, risk areas of acute myocardial infarction were documented in the acute stage, and then these images were evaluated for how well they reflected muscle viability, contractile reserve and coronary stenotic progression subsequent to reperfusion therapy. Patients who only experienced a first attack of myocardial infarction were enrolled. In total, 36 cases who had had the occluded artery successfully reperfused were examined during the past year. They had no significant vessel disease except for the culprit single artery. The patients were comprised of 32 men and 4 women. The mean age was 59.5 years. All patients underwent coronary angiography and left ventricular (LV) angiography in the emergency room. BMIPP/Tl and PYP myocardial SPECT were conducted in the acute stage and chronic stage. In the chronic stage LV angiography was repeated to assess the improvement of LV wall motion. The response to postextrasystolic potentiation (PESP) testing was performed to estimate myocardial contractile reserve. The risk area of acute myocardial infarction (AMI) was documented by reduced BMIPP accumulation. The size of reduced BMIPP accumulation was larger than that of PYP accumulation. A BMIPP/Tl discrepancy and PYP accumulation were documented to assess myocardial viability. Both improvement in LV wall motion and augmentation of PESP response were more closely related to a BMIPP/Tl discrepancy in the presence or absence of PYP accumulation. Therefore, it would be possible to evaluate myocardial viability and contractile reserve by the BMIPP/Tl discrepancy. In patients with good viability, it is important to predict whether there is coronary stenotic progression or not. In this study, we demonstrated that most patients with improved BMIPP images had no significant progression at the site of intervention. Serial observation of BMIPP images from the acute stage to the chronic stage might

Sharp-tailed Grouse and Pygmy Rabbit Wildlife Mitigation Project

International Nuclear Information System (INIS)

1992-10-01

The Proposed Action is needed to protect and enhance shrub-steppe and riparian habitat for sharp-tailed grouse (Tympanuchus phasianellus columbianus), Pygmy rabbits (Brachylagus idahoensis), and other indigenous wildlife species. The purpose of the Proposed Action is to compensate, in part, for wildlife habitat lost from the construction of Grand Coulee Dam and the inundation of Lake Roosevelt. Bonneville Power Administration proposes to fund management agreements, conservation easements, acquisition of fee title, or a combination of these on as many as 29,000 acres in Lincoln and Douglas Counties to improve shrub-steppe and riparian habitat for sharp-tailed grouse and pygmy rabbits. The BPA also proposes to fund habitat improvements (enhancements) on project lands including existing public lands. Proposed habitat treatments would include control of grazing; planting of native trees, shrubs, forbs and grasses; protection of wetlands and streambanks; herbicide use; fire prescriptions; and wildfire suppression. Proposed management activities may include predator control, population introductions, and control of crop depredation

Dosimetry in myocardial perfusion imaging

Energy Technology Data Exchange (ETDEWEB)

Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear. Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

2011-07-01

This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

Dosimetry in myocardial perfusion imaging

International Nuclear Information System (INIS)

Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C.

2011-01-01

This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

Nifedipine for angina and acute myocardial ischemia

NARCIS (Netherlands)

P.G. Hugenholtz (Paul); J.W. de Jong (Jan Willem); P.D. Verdouw (Pieter); P.W.J.C. Serruys (Patrick)

1983-01-01

textabstractThis paper reviews the mechanisms believed to be responsible for myocardial ischaemia and the mode of action of calcium antagonist drugs. The clinical management of patients with myocardial ischaemia is discussed in the context of current knowledge about patho-physiology and drug action.

Scan analysis in myocardial infarction

Energy Technology Data Exchange (ETDEWEB)

Ell, P J [Landesunfallkrankenhaus, Feldkirch (Austria). Inst. fuer Strahlenmedizin

1976-08-01

Myocardial scans with sup(99m)Tc-labelled phosphates are reported to be useful in the diagnosis of acute myocardial infarction. A retrospective survey of 205 patients referred for sup(99m)Tc-phophate bone scanning and with no evidence of recent heart disease revealed an occurrence of 10% of false positive images, that is to say, uptake of phosphate in non-infarcted mayocardium. These striking findings stress the need for critical assessment of the usefulness of this diagnostic technique.

Assessment of myocardial viability by MR imaging

International Nuclear Information System (INIS)

Sandstede, Joern J.W.

2003-01-01

Diagnosis of myocardial viability after infarction focuses on the prediction of functional improvement of dysfunctional myocardium after revascularization therapy. Magnetic resonance imaging provides different approaches for the detection of myocardial viability. Measurement of end-diastolic wall thickness is easy to perform and has a high sensitivity, but a low specificity, and can only be used 4 months after myocardial infarction due to infarct healing processes. Low-dose dobutamine stress has a good sensitivity with a high specificity for the prediction of wall motion improvement, but this is only true for patients with a singular dysfunctional area and only slightly depressed cardiac function. Late enhancement allows for direct visualization of necrotic or scarred tissue. By measuring the transmural extent of late enhancement, the probability of mechanical improvement can precisely be given. Imaging of microvascular obstruction by first-pass perfusion or late enhancement gives additional information on viability and patient prognosis. Metabolic imaging techniques, such as 31 P-MR spectroscopy and 23 Na-MR imaging, provide further insights into the mechanisms of myocardial infarction and viability. In conclusion, cardiac MRI offers several clinically usable approaches for the assessment of myocardial viability and will probably become the method of choice in the near future. (orig.)

Benefits of lifelong exercise training on left ventricular function after myocardial infarction.

Science.gov (United States)

Maessen, Martijn Fh; Eijsvogels, Thijs Mh; Stevens, Guus; van Dijk, Arie Pj; Hopman, Maria Te

2017-11-01

Background Endurance exercise training induces cardio-protective effects, but athletes are not exempted from a myocardial infarction. Evidence from animal studies suggests that exercise training attenuates pathological left ventricular remodelling following myocardial infarction. We tested the hypothesis that lifelong exercise training is related to attenuated pathological left ventricular remodelling after myocardial infarction as evidenced by better left ventricular systolic function in veteran athletes compared to sedentary peers. Design This was a cross-sectional study. Methods Sixty-five males (60 ± 6 years) were included and allocated to four groups based on lifelong exercise training volumes: (a) athletes ( n = 18), (b) post-myocardial infarction athletes (athletes + myocardial infarction, n = 20), (c) sedentary controls ( n = 13), and (d) post-myocardial infarction controls (sedentary controls + myocardial infarction, n = 14). Athletes were lifelong (≥20 years) highly physically active (≥30 metabolic equivalent of task (MET)-h/week), whereas sedentary controls did not meet the exercise guidelines (creatine-kinase, creatinine, aspartate transaminase and lactate dehydrogenase) following myocardial infarction and infarct location did not differ between athletes + myocardial infarction and sedentary controls + myocardial infarction. Left ventricular ejection fraction was significantly higher in athletes (61% ± 4), athletes + myocardial infarction (58% ± 4) and sedentary controls (57% ± 6) compared to sedentary controls + myocardial infarction (51% ± 7; p athletes (-19% (-21% to -17%), athletes + myocardial infarction (-16% (-20% to -12%)), and sedentary controls (-15% (-18% to -14%) compared to sedentary controls + myocardial infarction (-13% (-15% to -8%), p athletes.

Improvement in perception of image sharpness through the addition of noise and its relationship with memory texture

Science.gov (United States)

Wan, Xiazi; Kobayashi, Hiroyuki; Aoki, Naokazu

2015-03-01

In a preceding study, we investigated the effects of image noise on the perception of image sharpness using white noise, and one- and two-dimensional single-frequency sinusoidal patterns as stimuli. This study extends our preceding study by evaluating natural color images, rather than black-and-white patterns. The results showed that the effect of noise in improving image sharpness perception is more evident in blurred images than in sharp images. This is consistent with the results of the preceding study. In another preceding study, we proposed "memory texture" to explain the preferred granularity of images, as a concept similar to "memory color" for preferred color reproduction. We observed individual differences in type of memory texture for each object, that is, white or 1/f noise. This study discusses the relationship between improvement of sharpness perception by adding noise, and the memory texture, following its individual differences. We found that memory texture is one of the elements that affect sharpness perception.

Comparative study of body surface isopotential map, left ventriculogram and thallium-201 myocardial scintigram in patients with old lateral myocardial infarction

International Nuclear Information System (INIS)

Matsumoto, Naoyuki

1988-01-01

In 16 patients with old lateral myocardial infarction, body surface isopotential maps and 12 lead electrocardiograms were compared with left ventriculographic findings. In addition 8 of these subjects were performed thallium-201 myocardial scintigraphy in order to determine the location and extent of myocardial necrosis. Common 12 lead electrocardiographic findings of the subjects were initial Q waves more than 30 msec and inverted T waves in only aVL lead. The patients were classified into 4 groups according to the location and extent of ventricular wall motion abnormalities group I (6 cases) showed hypokinesis in the anterior segment, group II (5 cases): akinesis in the anterior segment and hypokinesis in the seg. 6, group III (4 cases): hypokinesis in the anterior segment and seg. 7, group IV (1 case): hypokinesis in the anterior segment and seg. 4, 7. And each of the 4 groups demonstrated characteristic findings of surface isopotential maps. Group II with coexisting hypokinesis in the seg. 6 showed surface isopotential maps additional pattern of anterior myocardial infarction, and group III with coexisting hypokinesis in the seg. 7 showed additional patterns of posterior myocardial infarction. The classification according to the abnormality of ventricular wall motion was also conformed with the thallium-201 myocardial scintigraphic findings except one case. These results suggest that body surface isopotential map is more useful than the 12 lead electrocardiogram in detecting the location and extent of left ventricular wall motion abnormality in patients with old lateral myocardial infarction. (author) 53 refs

Comparison between fragmented QRS and Q waves in myocardial scar detection using myocardial perfusion single photon emission computed tomography.

Science.gov (United States)

Dabbagh Kakhki, Vahid Reza; Ayati, Narjess; Zakavi, Seyed Rasoul; Sadeghi, Ramin; Tayyebi, Mohammad; Shariati, Farzaneh

2015-01-01

Accurate diagnosis of myocardial infarction (MI) is of paramount importance in patient management, which necessitates the development of efficient and accurate diagnostic methods. Q wave is not present in all patients with MI, and its prevalence is declining. Recently, fragmented QRS (fQRS) complex has been introduced as a marker of prior MI. To investigate diagnostic value of fQRS compared to Q wave. We included 500 consecutive patients with known or suspected coronary artery disease who underwent two days of gated myocardial perfusion imaging using dipyridamole pharmacologic stress. Electrocardiogram (ECG) was evaluated to detect fQRS as well as Q-wave. Finally, subjects were compared in terms of ventricular perfusion and function indices. A total of 207 men and 269 women with mean age of 57.06 ± 12 years were studied. ECG analysis showed that 14.3% of the patients had both fQRS and Q waves, 30.7% had fQRS, and 3.8% had Q waves. Fixed myocardial perfusion defect was noted in 22.3% of patients according to MPIs. Sensitivity, specificity, and positive and negative predictive values for myocardial scar detection were 78%, 65%, 39%, and 91%, respectively, for fQRS and 61%, 94%, 76%, and 89%, respectively, for Q wave. Although fQRS had lower specificity compared to Q wave in the detection of myocardial scar, due to higher sensitivity and negative predictive value can be an invaluable diagnostic index. There is also an incremental value for fQRS in association with Q-wave in myocardial scar assessment.

Serial change of 123I-BMIPP SPECT imaging during recovery from stunned myocardium after acute myocardial infarction. Correlation with 201Tl and two-dimensional echocardiography

International Nuclear Information System (INIS)

Nakano, Akira; Kondo, Makoto; Tokunaga, Satoshi; Akiyama, Kiyozumi; Mori, Yoshihisa; Nosue, Yasuhiro; Makita, Toshinori; Tanio, Hitoshi; Shimono, Yukio

1995-01-01

Using 123 I-β-methyl iodophenyl pentadecanoic acid ( 123 I-BMIPP), we investigated changes in myocardial fatty acid metabolism at recovery from stunned myocardium after acute myocardial infarction (AMI), correlation with recovery of regional wall motion and thallium-201 ( 201 Tl) distribution in particular. The subjects were 15 patients who underwent successful reperfusion therapy after the first onset of AMI. None of the patients had multi-vessel disease or ischemic episode during their clinical course. Patients underwent 123 I-BMIPP scintigraphy, 201 Tl scintigraphy and two-dimensional echocardiography during the acute and chronic phases. Then, we compared regional wall motion with distribution of 123 I-BMIPP and 201 Tl. Regional wall motion and SPECT were evaluated by the established 16 segment model. In patients, showing serial improvement in regional wall motion, there was 80.0% (8/10) showed normal 201 Tl distribution during the acute phase or normalized during the chronic phase. However, distribution of 123 I-BMIPP normalized only in 10.0% (1/10) of this group. In examination of each segment that showed serial improvement in regional wall motion, 92.3% (24/26) of these segments showed normal distribution of 201 Tl during the acute phase or normalized distribution during chronic phase, despite distribution of 123 I-BMIPP improved in only 3.8% (1/26) of these segments. These indicate that, in the process of recovery from myocardial stunning after AMI, abnormal distribution of 123 I-BMIPP continued longer than abnormal distribution of 201 Tl. (author)

Current status of sharps waste management in the lower-level ...

African Journals Online (AJOL)

Key words: Sharps waste management, health facilities, infection, Tanzania ... and hence improve infection prevention and control at work places in Tanzania. .... The UNICEF /WHO safety boxes were observed in 31 (23%) of the LLHFs, while ...

Consistency relations for sharp inflationary non-Gaussian features

Energy Technology Data Exchange (ETDEWEB)

Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Blanco Encalada 2008, Santiago (Chile); Soto, Alex, E-mail: sander.mooij@ing.uchile.cl, E-mail: gpalmaquilod@ing.uchile.cl, E-mail: gpanotop@ing.uchile.cl, E-mail: gatogeno@gmail.com [Departamento de Física, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago (Chile)

2016-09-01

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

Consistency relations for sharp inflationary non-Gaussian features

International Nuclear Information System (INIS)

Mooij, Sander; Palma, Gonzalo A.; Panotopoulos, Grigoris; Soto, Alex

2016-01-01

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information about the physics that produced them. Small sharp features could be suppressed at the level of the two-point correlation function, making them undetectable in the power spectrum, but could be amplified at the level of the three-point correlation function, offering us a window of opportunity to uncover them in the non-Gaussian bispectrum. In this article, we show that sharp features may be analyzed using only data coming from the three point correlation function parametrizing primordial non-Gaussianity. More precisely, we show that if features appear in a particular non-Gaussian triangle configuration (e.g. equilateral, folded, squeezed), these must reappear in every other configuration according to a specific relation allowing us to correlate features across the non-Gaussian bispectrum. As a result, we offer a method to study scale-dependent features generated during inflation that depends only on data coming from measurements of non-Gaussianity, allowing us to omit data from the power spectrum.

Small break critical discharge: The roles of vapor and liquid entrainment in a stratified two-phase region upstream of the break

International Nuclear Information System (INIS)

Schrock, V.E.; Revankar, S.T.; Mannheimer, R.; Wang, C.H.

1986-12-01

The main objective of this research program was to perform an experimental investigation on the phenomena of two-phase critical flow through small break from a horizontal pipe which contained a stratified two phase flow. Stagnation conditions investigated were saturated steam-water, and air-cold water at pressures ranging from 0.37 MPa to 1.07 MPa. The small breaks employed were cylindrical tubes of diameters 3.96 mm, 6.32 mm, and 10.1 mm with sharp-edged entrance. For breaks resulting from a small hole in a primary coolant pipe or in a small pipe, a sharp-edged orifice or a sharp-edged tube can be the approximation

Thrombolysis significantly reduces transient myocardial ischaemia following first acute myocardial infarction

DEFF Research Database (Denmark)

Mickley, H; Pless, P; Nielsen, J R

1992-01-01

In order to investigate whether thrombolysis affects residual myocardial ischaemia, we prospectively performed a predischarge maximal exercise test and early out-of-hospital ambulatory ST segment monitoring in 123 consecutive men surviving a first acute myocardial infarction (AMI). Seventy......-four patients fulfilled our criteria for thrombolysis, but only the last 35 patients included received thrombolytic therapy. As thrombolysis was not available in our Department at the start of the study, the first 39 patients included were conservatively treated (controls). No significant differences...... in baseline clinical characteristics were found between the two groups. In-hospital atrial fibrillation and digoxin therapy was more prevalent in controls (P less than 0.05). During exercise, thrombolysed patients reached a higher maximal work capacity compared with controls: 160 +/- 41 vs 139 +/- 34 W (P...

Correlation between myocardial Thallium-201 kinetics, myocardial lactate metabolism and coronary angiographic findings in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Hanrath, P.; Mathey, D.; Thiel, U.; Kupper, W.; Bleifeld, W.; Mantz, R.; Vorbringer, H.; Schneider, C.

1980-01-01

In 20 patients with idiopathic hypertrophic obstructive and nonobstructive cardiomyopathy (IHSS), biphasic Thallium-201 myocardial scintigraphy was performed. Regional myocardial Thallium-201 kinetics of these patients were analysed by a semiquantitative computerized method and compared with those of 6 normal subjects. In 12 of 18 with IHSS and no coronary artery disease 26 regions of interest with irreversible and 6 regions of interest with reversible Thallium-201 defects could be detected. Most of the Thallium-201 defects were localized in the interventricular septum. The defects were not related to the age of the patients and there was no relationship between the occurence of reversible Thallium-201 defects and pathological myocardial lactate extraction rate during maximal atrial pacing measured in 14 patients. The percentage (6.8%) of irreversible defect regions in patients with LV outflow obstruction at rest (n = 13) was more than twice higher compared to those (n = 5, 3.2%) without LV outflow obstruction or no provocative pressure gradient, resp. These data suggest that IHSS often associated with regional ischemic myocardial fibrosis despite normal coronary arteries. Therefore in these patients Thallium scintigraphy cannot be used as a noninvasive screening method to exclude or prove coronary artery disease. (orig.) [de

Stereotactic hypofractionated accurate radiotherapy of the prostate (SHARP), 33.5 Gy in five fractions for localized disease: First clinical trial results

International Nuclear Information System (INIS)

Madsen, Berit L.; Hsi, R. Alex; Pham, Huong T.; Fowler, Jack F.; Esagui, Laura C.; Corman, John

2007-01-01

Purpose: To evaluate the feasibility and toxicity of stereotactic hypofractionated accurate radiotherapy (SHARP) for localized prostate cancer. Methods and Materials: A Phase I/II trial of SHARP performed for localized prostate cancer using 33.5 Gy in 5 fractions, calculated to be biologically equivalent to 78 Gy in 2 Gy fractions (α/β ratio of 1.5 Gy). Noncoplanar conformal fields and daily stereotactic localization of implanted fiducials were used for treatment. Genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated by American Urologic Association (AUA) score and Common Toxicity Criteria (CTC). Prostate-specific antigen (PSA) values and self-reported sexual function were recorded at specified follow-up intervals. Results: The study includes 40 patients. The median follow-up is 41 months (range, 21-60 months). Acute toxicity Grade 1-2 was 48.5% (GU) and 39% (GI); 1 acute Grade 3 GU toxicity. Late Grade 1-2 toxicity was 45% (GU) and 37% (GI). No late Grade 3 or higher toxicity was reported. Twenty-six patients reported potency before therapy; 6 (23%) have developed impotence. Median time to PSA nadir was 18 months with the majority of nadirs less than 1.0 ng/mL. The actuarial 48-month biochemical freedom from relapse is 70% for the American Society for Therapeutic Radiology and Oncology definition and 90% by the alternative nadir + 2 ng/mL failure definition. Conclusions: SHARP for localized prostate cancer is feasible with minimal acute or late toxicity. Dose escalation should be possible

T1 mapping of the myocardium: Intra-individual assessment of the effect of field strength, cardiac cycle and variation by myocardial region

Directory of Open Access Journals (Sweden)

Kawel Nadine

2012-05-01

Full Text Available Abstract Background Myocardial T1 relaxation time (T1 time and extracellular volume fraction (ECV are altered in the presence of myocardial fibrosis. The purpose of this study was to evaluate acquisition factors that may result in variation of measured T1 time and ECV including magnetic field strength, cardiac phase and myocardial region. Methods 31 study subjects were enrolled and underwent one cardiovascular MR exam at 1.5 T and two exams at 3 T, each on separate days. A Modified Look-Locker Inversion Recovery (MOLLI sequence was acquired before and 5, 10, 12, 20, 25 and 30 min after administration of 0.15 mmol/kg gadopentetate dimeglumine (Gd-DTPA; Magnevist at 1.5 T (exam 1. For exam 2, MOLLI sequences were acquired at 3 T both during diastole and systole, before and after administration of Gd-DTPA (0.15 mmol/kg Magnevist.Exam 3 was identical to exam 2 except gadobenate dimeglumine was administered (Gd-BOPTA; 0.1 mmol/kg Multihance. T1 times were measured in myocardium and blood. ECV was calculated by (ΔR1myocardium/ΔR1blood*(1-hematocrit. Results Before gadolinium, T1 times of myocardium and blood were significantly greater at 3 T versus 1.5 T (28% and 31% greater, respectively, p  Conclusion ECV is similar at field strengths of 1.5 T and 3 T. Due to minor variations in T1 time and ECV during the cardiac cycle and in different myocardial regions, T1 measurements should be obtained at the same cardiac phase and myocardial region in order to obtain consistent results.

SHARP, a first step towards a full sized Jules Verne Launcher

Energy Technology Data Exchange (ETDEWEB)

Bertolini, L.R.; Hunter, J.W. [Lawrence Livermore National Lab., CA (United States); Powell, J.R. [Brookhaven National Lab., Upton, NY (United States); Tidman, D.A. [GT-Devices, Inc., Alexandria, VA (United States)

1993-05-01

A vital element for space exploration and utilization is the ability to affordably place large quantities of consumables and building material into low earth orbit. Calculations and supportive data indicate this can be done with a large hydrogen gas gun referred to as the Jules Verne Launcher (JVL). We present a design for the JVL based upon the concept of side injecting preheated hydrogen along a long barrel. This dramatically reduces the peak pressures in the launcher as well as the pressures and g-loads at the vehicle. The JVL has the promise of reducing payload delivery costs to Low Earth Orbit (LEO) to below $500/kg. The Super High Altitude Research Project (SHARP) is a conventional two-stage hydrogen gas gun which is configured to launch 5 kg packages on suborbital trajectories. It is the first step towards the much larger Jules Verne system and will demonstrate several important features of the larger system. SHARP is currently in the middle of a series of tests aimed at its first milestone. This is to launch 5 kg at 4 km/sec horizontally. In its inclined configuration SHARP should launch vehicles to apogees in excess of 400 km and ranges in excess of 700 km.

Intermittent peripheral tissue ischemia during coronary ischemia reduces myocardial infarction through a KATP-dependent mechanism: first demonstration of remote ischemic perconditioning

DEFF Research Database (Denmark)

Schmidt, Michael Rahbek; Smerup, M; Konstantinov, I E

2006-01-01

. Intermittent limb ischemia during myocardial ischemia reduces MI, preserves global systolic and diastolic function, and protects against arrhythmia during the reperfusion phase through a K(ATP) channel-dependent mechanism. Understanding this process may have important therapeutic implications for a range...

Intravenous streptokinase therapy in acute myocardial infarction: Assessment of therapy effects by quantitative 201Tl myocardial imaging (including SPECT) and radionuclide ventriculography

International Nuclear Information System (INIS)

Koehn, H.; Bialonczyk, C.; Mostbeck, A.; Frohner, K.; Unger, G.; Steinbach, K.

1984-01-01

To evaluate a potential beneficial effect of systemic streptokinase therapy in acute myocardial infarction, 36 patients treated with streptokinase intravenously were assessed by radionuclide ventriculography and quantitative 201 Tl myocardial imaging (including SPECT) in comparison with 18 conventionally treated patients. Patients after thrombolysis had significantly higher EF, PFR, and PER as well as fewer wall motion abnormalities compared with controls. These differences were also observed in the subset of patients with anterior wall infarction (AMI), but not in patients with inferior wall infarction (IMI). Quantitative 201 Tl imaging demonstrated significantly smaller percent myocardial defects and fewer pathological stress segments in patients with thrombolysis compared with controls. The same differences were also found in both AMI and IMI patients. Our data suggest a favorable effect of intravenous streptokinase on recovery of left ventricular function and myocardial salvage. Radionuclide ventriculography and quantitative 201 Tl myocardial imaging seem to be reliable tools for objective assessment of therapy effects. (orig.)

DEPRESSION, ANXIETY AND MYOCARDIAL INFARCTION: EVERYTHING JUST BEGINS (PART I

Directory of Open Access Journals (Sweden)

Y. A. Vasyuk

2015-12-01

Full Text Available A review is devoted to a comorbidity of myocardial infarction and anxious and depressive disorders. In the first part data concerning prevalence of depression in myocardial infarction, pathophysiological mechanisms connecting depression and ischemic heart disease (IHD are given. Influence of concomitant depressive disorders on clinical state and forecast of patients after myocardial infarction is discussed. The second part of the review (Rational Pharmacother. Cardiol. 2007, 4 will be devoted to the anxious disorders in myocardial infarction as well as to influence of anxious and depressive disorders on life quality of patients with myocardial infarction. Besides, contemporary approaches to the therapy of anxious and depressive disorders in patients with IHD will be discussed.

DEPRESSION, ANXIETY AND MYOCARDIAL INFARCTION: EVERYTHING JUST BEGINS. PART II

Directory of Open Access Journals (Sweden)

Y. A. Vasyuk

2015-12-01

Full Text Available A review is devoted to a comorbidity of myocardial infarction and anxious and depressive disorders. In the first part (Rational Pharmacother. Cardiol. 2007;3:41-51 data concerning prevalence of depression in myocardial infarction, pathophysiological mechanisms connecting depression and ischemic heart disease (IHD were given. Influence of concomitant depressive disorders on clinical state and forecast of patients after myocardial infarction was discussed. The second part of the review is devoted to the anxious disorders in myocardial infarction as well as to influence of anxious and depressive disorders on life quality of patients with myocardial infarction. Besides, contemporary approaches to the therapy of anxious and depressive disorders in patients with IHD are discussed.

Increase in mean platelet volume in patients with myocardial bridge.

Science.gov (United States)

Bilen, Emine; Tanboga, Ibrahim Halil; Kurt, Mustafa; Kocak, Umran; Ayhan, Huseyin; Keles, Telat; Bozkurt, Engin

2013-01-01

Myocardial bridge is associated with atherosclerosis altered in shear stress and endothelial dysfunction. Mean platelet volume (MPV), a determinant of platelet activation, is shown to be related with atherosclerosis and endothelial dysfunction. In this study, we aimed to evaluate platelet function assessed by MPV in patients with myocardial bridge. Forty-two patients with myocardial bridge in the left anterior descending artery (LAD) and 43 age- and gender-matched healthy participants were included in the study. Myocardial bridging was defined as an intramyocardial systolic compression or milking of a segment of an epicardial coronary artery on angiography. For the entire study population, MPV was measured using an automatic blood counter. The study population consisted of 42 patients with myocardial bridge (52.7 ± 10.2, 76.2% male) and 43 age- and sex-matched healthy control participants (52.1 ± 10.4, 74.4% male). Compared to the control group, MPV value was significantly higher in patients with myocardial bridge (8.9 ± 1.24 vs 8.3 ± 0.78; P = .01). Further, there were no significant differences between groups regarding hemoglobin level, platelet count, fasting blood glucose, and creatinine levels. Our study findings indicated that myocardial bridge is associated with elevated MPV values. Our results might partly explain the increased cardiovascular events in patients with myocardial bridge.

Diabetes subdiagnosticado e necrose miocárdica: preditores de hiperglicemia no infarto do miocárdio Unrecognized diabetes and myocardial necrosis: predictors of hyperglycemia in myocardial infarction

Directory of Open Access Journals (Sweden)

Renata Teixeira Ladeira

2013-05-01

Full Text Available FUNDAMENTO: Hiperglicemia na fase aguda do infarto do miocárdio é importante fator prognóstico. Entretanto, sua fisiopatologia não está completamente elucidada. OBJETIVO: Analisar simultaneamente correlação entre hiperglicemia e marcadores bioquímicos relacionados ao estresse,metabolismo glicídico e lipídico, coagulação, inflamação e necrose miocárdica. MÉTODOS: Oitenta pacientes com infarto agudo do miocárdio foram incluídos prospectivamente. Os parâmetros analisados foram: glicose, hormônios do estresse (cortisol e norepinefrina, fatores do metabolismo glicídico [hemoglobina glicada (HbA1c, insulina], lipoproteínas (colesterol total, LDL, HDL, LDL eletronegativa minimamente modificada e adiponectina, glicerídeos (triglicérides, VLDL e ácido graxo, fatores da coagulação (fator VII, fibrinogênio,inibidor do ativador do plasminogênio-1, inflamação (proteína C reativa ultrassensível e necrose miocárdica (CK-MB e troponina. Variáveis contínuas foram convertidas em graus de pertinência por intermédio de lógica fuzzy. RESULTADOS: Houve correlação significativa entre hiperglicemia e metabolismo glicídico (p BACKGROUND: Hyperglycemia in the acute phase of myocardial infarction is an important prognostic factor. However, its pathophysiology is not fully understood. OBJECTIVE: To analyze simultaneously the correlation between hyperglycemia and biochemical markers related to stress, glucose and lipid metabolism, coagulation, inflammation, and myocardial necrosis. METHODS Eighty patients with acute myocardial infarction were prospectively included. The following parameters were analyzed: blood glucose; stress hormones (cortisol and norepinephrine; glucose metabolism factors [glycated hemoglobin (HbA1c; insulin]; lipoproteins (total cholesterol, LDL, HDL, minimally modified electronegative LDL, and adiponectin; glycerides (triglycerides, VLDL and fatty acids; coagulation factors (factor VII, fibrinogen, plasminogen

Application of the SHARP Toolkit to Sodium-Cooled Fast Reactor Challenge Problems

Energy Technology Data Exchange (ETDEWEB)

Shemon, E. R. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Yu, Y. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Kim, T. K. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

2017-09-30

The Simulation-based High-efficiency Advanced Reactor Prototyping (SHARP) toolkit is under development by the Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign of the U.S. Department of Energy, Office of Nuclear Energy. To better understand and exploit the benefits of advanced modeling simulations, the NEAMS Campaign initiated the “Sodium-Cooled Fast Reactor (SFR) Challenge Problems” task, which include the assessment of hot channel factors (HCFs) and the demonstration of zooming capability using the SHARP toolkit. If both challenge problems are resolved through advanced modeling and simulation using the SHARP toolkit, the economic competitiveness of a SFR can be significantly improved. The efforts in the first year of this project focused on the development of computational models, meshes, and coupling procedures for multi-physics calculations using the neutronics (PROTEUS) and thermal-hydraulic (Nek5000) components of the SHARP toolkit, as well as demonstration of the HCF calculation capability for the 100 MWe Advanced Fast Reactor (AFR-100) design. Testing the feasibility of the SHARP zooming capability is planned in FY 2018. The HCFs developed for the earlier SFRs (FFTF, CRBR, and EBR-II) were reviewed, and a subset of these were identified as potential candidates for reduction or elimination through high-fidelity simulations. A one-way offline coupling method was used to evaluate the HCFs where the neutronics solver PROTEUS computes the power profile based on an assumed temperature, and the computational fluid dynamics solver Nek5000 evaluates the peak temperatures using the neutronics power profile. If the initial temperature profile used in the neutronics calculation is reasonably accurate, the one-way offline method is valid because the neutronics power profile has weak dependence on small temperature variation. In order to get more precise results, the proper temperature profile for initial neutronics calculations was obtained from the

Impairment of myocardial perfusion in children with sickle cell disease

International Nuclear Information System (INIS)

Maunoury, C.; Acar, P.; Montalembert, M. de

2003-01-01

While brain, bone and spleen strokes are well documented in children with sickle cell disease (SCD), impairment of myocardial perfusion is an unknown complication. Non invasive techniques such as exercise testing and echocardiography have a low sensitivity to detect myocardial ischemia in patients with SCD. We have prospectively assessed myocardial perfusion with Tl-201 SPECT in 23 patients with SCD (10 female, 13 male, mean age 12 ± 5 years). Myocardial SPECT was performed after stress and 3 hours later after reinjection on a single head gamma camera equipped with a LEAP collimator (64 x 64 matrix size format, 30 projections over 180 deg C, 30 seconds per step). Left ventricular ejection fraction (LVEF) was assessed by equilibrium radionuclide angiography at rest on the same day. Myocardial perfusion was impaired in 14/23 patients: 9 reversible defects and 5 fixed defects. The left ventricular cavity was dilated in 14/23 patients. The mean LVEF was 63 ± 9%. There was no relationship between myocardial perfusion and left ventricular dilation or function. The frequent impairment of myocardial perfusion in children with SCD could lead to suggest a treatment with hydroxyurea, an improvement of perfusion can be noted with hydroxyurea. (author)

Summer High School Apprenticeship Research Program (SHARP) of the National Aeronautics and Space Administration

Science.gov (United States)

1984-01-01

A total of 125 talented high school students had the opportunity to gain first hand experience about science and engineering careers by working directly with a NASA scientist or engineer during the summer. This marked the fifth year of operation for NASA's Summer High School Apprenticehsip Research Program (SHARP). Ferguson Bryan served as the SHARP contractor and worked closely with NASA staff at Headquarters and the eight participating sites to plan, implement, and evaluate the Program. The main objectives were to strengthen SHARP and expand the number of students in the Program. These eight sites participated in the Program: Ames Research Center North, Ames' Dryden Flight Research Facility, Goddard Space Flight Center, Goddard's Wallops Flight Facility, Kennedy Space Center, Langley Research Center, Lewis Research Center, and Marshall Space Flight Center.

A sharp Rogers–Shephard type inequality for Orlicz-difference body ...

Indian Academy of Sciences (India)

Abstract. In this paper, we prove a sharp Rogers–Shephard type inequality for the Orlicz-difference body of planar convex bodies, which extend the works of Bianchini and Colesanti (Proc. Amer. Math. Soc. 138(7) (2008) 2575–2582).

Quantifying the margin sharpness of lesions on radiological images for content-based image retrieval

International Nuclear Information System (INIS)

Xu Jiajing; Napel, Sandy; Greenspan, Hayit; Beaulieu, Christopher F.; Agrawal, Neeraj; Rubin, Daniel

2012-01-01

Purpose: To develop a method to quantify the margin sharpness of lesions on CT and to evaluate it in simulations and CT scans of liver and lung lesions. Methods: The authors computed two attributes of margin sharpness: the intensity difference between a lesion and its surroundings, and the sharpness of the intensity transition across the lesion boundary. These two attributes were extracted from sigmoid curves fitted along lines automatically drawn orthogonal to the lesion margin. The authors then represented the margin characteristics for each lesion by a feature vector containing histograms of these parameters. The authors created 100 simulated CT scans of lesions over a range of intensity difference and margin sharpness, and used the concordance correlation between the known parameter and the corresponding computed feature as a measure of performance. The authors also evaluated their method in 79 liver lesions (44 patients: 23 M, 21 F, mean age 61) and 58 lung nodules (57 patients: 24 M, 33 F, mean age 66). The methodology presented takes into consideration the boundary of the liver and lung during feature extraction in clinical images to ensure that the margin feature do not get contaminated by anatomy other than the normal organ surrounding the lesions. For evaluation in these clinical images, the authors created subjective independent reference standards for pairwise margin sharpness similarity in the liver and lung cohorts, and compared rank orderings of similarity used using our sharpness feature to that expected from the reference standards using mean normalized discounted cumulative gain (NDCG) over all query images. In addition, the authors compared their proposed feature with two existing techniques for lesion margin characterization using the simulated and clinical datasets. The authors also evaluated the robustness of their features against variations in delineation of the lesion margin by simulating five types of deformations of the lesion margin

When is 201Tl myocardial scintigraphy indicated?

International Nuclear Information System (INIS)

Klepzig, H. Jr.; Kaltenbach, M.

1987-01-01

Myocardial scintigraphy with thallium-201 has met with good acceptance in cardiology and has proven its value. The method implies only low risk and yields diagnostic results that allow verification or disqualification of suspected myocardial ischemia in those cases where there is only reduced accuracy of the exercise electrocardiogram. (TRV) [de

Sharp estimates for damped oscillatory integrals

International Nuclear Information System (INIS)

Ikromov, I.A.; Shaimardanov, S.S.

2004-05-01

We consider a real-analytic hypersurface S in R 3 with surface measure dS, ψ is a smooth function with compact support, and we let dμ α be the surface measure with dμ α = ψ vertical bar K(x) vertical bar α dS, where K(x) is the Gaussian curvature of the surface. We show that if S is a real analytic hypersurface with one non-vanishing principal curvature and α > 1, then μ-circumflex α (ξ) decays as O (vertical bar ξ vertical bar -1 ). The well-known examples show that the estimate for the exponent α is sharp. (author)

Inferior ST-Elevation Myocardial Infarction Associated with Takotsubo Cardiomyopathy

Directory of Open Access Journals (Sweden)

Oliver Koeth

2010-01-01

Full Text Available Takotsubo cardiomyopathy (TCM is usually characterized by transient left ventricular apical ballooning. Due to the clinical symptoms which include chest pain, electrocardiographic changes, and elevated myocardial markers, Takotsubo cardiomyopathy is frequently mimicking ST-elevation myocardial infarction in the absence of a significant coronary artery disease. Otherwise an acute occlusion of the left anterior descending coronary artery can produce a typical Takotsubo contraction pattern. ST-elevation myocardial infarction (STEMI is frequently associated with emotional stress, but to date no cases of STEMI triggering TCM have been reported. We describe a case of a female patient with inferior ST-elevation myocardial infarction complicated by TCM.

Enhanced Transmissions Through Three-dimensional Cascade Sharp Waveguide Bends Using C-slit Diaphragms.

Science.gov (United States)

Yang, Rui; Hu, Bowei; Zhang, Aofang; Gao, Dongxing; Wang, Hui; Shi, Ayuan; Lei, Zhenya; Yang, Pei

2017-03-21

Transmission properties through sharp rectangular waveguide bends are investigated to determine the cut-off bending angles of the wave propagation. We show that a simple metallic diaphragm at the bending corner with properly devised sub-wavelength defect apertures of C-slits would be readily to turn on the transmissions with scarce reflections of the propagating modes, while preserving the integrity of the transmitting fields soon after the bends. In particularly, our design also demonstrates the capability of eliminating all the unwanted cavity resonant transmissions that exist in the three-dimensional cascade sharp waveguide bends, and solely let the desired signals travel along the whole passage of the waveguide. The present approach, using C-slit diaphragms to support the sharp bending behaviors of the guided waves with greatly enhanced transmissions, would be especially effective in constructing novel waveguides and pave the way for the development of more compact and miniaturized electromagnetic systems that exploit these waveguide bends.

Myocardial bridges of the coronary arteries in the human fetal heart.

Science.gov (United States)

Cakmak, Yusuf Ozgür; Cavdar, Safiye; Yalin, Aymelek; Yener, Nuran; Ozdogmus, Omer

2010-09-01

During the last century, many investigators reported on myocardial bridges in the adult human heart. In the present study, 39 human fetal hearts (the mean gestastional age was 30 weeks) were studied for myocardial bridging, and the results were correlated with adult data. Among the 39 (27 male and 12 female) fetal hearts studied, 26 bridges were observed on 18 fetal hearts (46.2%). Ten of the bridges had one myocardial bridge, whereas double myocardial bridges were observed in eight fetal hearts. The most frequent myocardial bridges were observed on the left anterior descending artery (LAD), which had 13 bridges (50%). Eight (30.7%) myocardial bridges were on the diagonal artery, and on the posterior descending artery there were five (19.3%). Myocardial bridges were not observed on the circumflex artery. The data presented in this study may provide potentially useful information for the preoperative evaluation of the newborn and may have a clinical implication for sudden fetal death.

Evaluation of the specificity of radionuclide myocardial imaging for detecting CAD

International Nuclear Information System (INIS)

Liu Xiujie

1992-01-01

In order to evaluate the specificity of radionuclide myocardial perfusion imaging for detecting coronary artery disease (CAD), 50 patients with normal coronary arteriography and radionuclide myocardial perfusion scintigraphy were analysed. The results from 201 T1 (20 cases) and 99m Tc-MIBI (30 cases) studies showed that out of 33 patients with no organic cardiovascular disease, 29 had normal myocardial imaging, and the specificity of radionuclide myocardial imaging for detecting CAD was 87.8%. 4 normal young women had false positive myocardial imaging. Out of 17 patients with cardiovascular disease and normal coronary arteriography, 15 patients had abnormal myocardial imaging. The final clinical diagnoses of these 15 patients were: 4 patients with hypertrophic cardiomyopathy, 3 with old myocardial infarction, 2 with myocarditis, 3 with small coronary vessel disease, 1 with congestive cardiomyopathy, and 2 with other cardiac disorder. The points of differentiation between CAD and other cardiovascular disease using radionuclide techniques were discussed

Acute myocardial infarction: 'telomerasing' for cardioprotection

OpenAIRE

Sanchís-Gomar, Fabián; Lucía Mulas, Alejandro

2015-01-01

Reactivating the telomerase gene through gene therapy after acute myocardial infarction (AMI) has been recently reported to improve survival in mice. Given that regular physical exercise also activates this gene, therapeutic and lifestyle interventions targeting telomerase need to be explored as possible additions to the current armamentarium for myocardial regeneration. 9.292 JCR (2015) Q1, 17/289 Biochemistry & mollecular biology, 17/187 Cell biology, 8/124 Medicine, research & experimen...

Effect of perindopril on the myocardial energy consumption in patients with heart failure after myocardial infarction

Directory of Open Access Journals (Sweden)

Da-Peng Li

2017-07-01

Full Text Available Objective: To explore the clinical efficacy of perinodopril in the treatment of heart failure in patients after myocardial infarction and effect on the myocardial energy consumption. Methods: A total of 87 patients with heart failure after myocardial infarction who were admitted in our hospital from August, 2014 to October, 2015 were included in the study and divided into the routine dose group (n=43, perinodopril 4 mg/d and high dose group (n=44, perinodopril 8 mg/d according to the long-term oral dose. All the patients were given perinodopril, continuously for 6 months. The changes of blood pressure and serum biochemical indicators before and after treatment in the two groups were compared. The changes of cardiac function indicators and myocardial energy consumption indicators before and after treatment in the two groups were compared. 6MWT 6 months and 1 year after treatment in the two groups was calculated. Results: The plasma BNP and H-FABP levels, LVEDD, LVESD, MEE, and cESS after treatment in the two groups were significantly reduced when compared with before treatment, and those in the high dose group were significantly lower than those in the low dose group. LVEF and FS after treatment in the two groups were significantly increased, and those in the high dose group were significantly greater than those in the routine dose group. The seurm potassium level after treatment in the high dose group was significantly elevated when compared with before treatment, but was not significantly different from that in the routine dose group. SBP, DBP, and Scr levels after treatment in the two groups were not significantly changed. 6MWT 6 months and 1 year after treatment in the high dose group was significantly greater than that in the routine dose group. Conclusions: Perinodopril in a high dose can significantly reduce the plasma BNP and H-FABP levels in patients with heart failure after myocardial infarction, inhibit the ventricular remodeling

Clinical significance of late high-degree atrioventricular block in patients with left ventricular dysfunction after an acute myocardial infarction--a Cardiac Arrhythmias and Risk Stratification After Acute Myocardial Infarction (CARISMA) substudy

DEFF Research Database (Denmark)

Gang, Uffe Jakob Ortved; Jøns, Christian; Jørgensen, Rikke Mørch

2011-01-01

High-degree atrioventricular block (HAVB) is a frequent complication in the acute stages of a myocardial infarction associated with an increased rate of mortality. However, the incidence and clinical significance of HAVB in late convalescent phases of an AMI is largely unknown. The aim of this st...... of this study was to assess the incidence and prognostic value of late HAVB documented by continuous electrocardiogram (ECG) monitoring in post-AMI patients with reduced left ventricular function....

The influence of surface stress on dislocation emission from sharp and blunt cracks in f.c.c. metals

DEFF Research Database (Denmark)

Schiøtz, Jakob

2000-01-01

We use computer simulations to study the behaviour of atomically sharp and blunted cracks in various fee metals. The simulations use effective medium potentials which contain many-body interactions. We find that when using potentials representing platinum and gold a sharp crack is stable with res......We use computer simulations to study the behaviour of atomically sharp and blunted cracks in various fee metals. The simulations use effective medium potentials which contain many-body interactions. We find that when using potentials representing platinum and gold a sharp crack is stable...... with respect to the emission of a dislocation from the crack tip, whereas for all other metals studied the sharp crack is unstable. This result cannot be explained by existing criteria for the intrinsic ductile/brittle behaviour of crack tips, but is probably caused by surface stresses. When the crack...... is no longer atomically sharp dislocation emission becomes easier in all the studied metals. The effect is relatively strong; the critical stress intensity factor for emission to occur is reduced by up to 20%. This behaviour appears to be caused by the surface stress near the crack tip. The surface stress...

Area at risk can be assessed by iodine-123-meta-iodobenzylguanidine single-photon emission computed tomography after myocardial infarction: a prospective study.

Science.gov (United States)

Hedon, Christophe; Huet, Fabien; Ben Bouallegue, Fayçal; Vernhet, Hélène; Macia, Jean-Christophe; Cung, Thien-Tri; Leclercq, Florence; Cade, Stéphane; Cransac, Frédéric; Lattuca, Benoit; Vandenberghe, D'Arcy; Bourdon, Aurélie; Benkiran, Meriem; Vauchot, Fabien; Gervasoni, Richard; D'estanque, Emmanuel; Mariano-Goulart, Denis; Roubille, François

2018-02-01

Myocardial salvage is an important surrogate endpoint to estimate the impact of treatments in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to evaluate the correlation between cardiac sympathetic denervation area assessed by single-photon emission computed tomography (SPECT) using iodine-123-meta-iodobenzylguanidine (I-MIBG) and myocardial area at risk (AAR) assessed by cardiac magnetic resonance (CMR) (gold standard). A total of 35 postprimary reperfusion STEMI patients were enrolled prospectively to undergo SPECT using I-MIBG (evaluates cardiac sympathetic denervation) and thallium-201 (evaluates myocardial necrosis), and to undergo CMR imaging using T2-weighted spin-echo turbo inversion recovery for AAR and postgadolinium T1-weighted phase sensitive inversion recovery for scar assessment. I-MIBG imaging showed a wider denervated area (51.1±16.0% of left ventricular area) in comparison with the necrosis area on thallium-201 imaging (16.1±14.4% of left ventricular area, Parea (P=0.23) and was adequately correlated (R=0.56, P=0.0002). Myocardial salvage evaluated by SPECT imaging (mismatch denervated but viable myocardium) was significantly higher than by CMR (P=0.02). In patients with STEMI, I-MIBG SPECT, assessing cardiac sympathetic denervation may precisely evaluate the AAR, providing an alternative to CMR for AAR assessment.

Assessment of myocardial perfusion and metabolism for assessment of myocardial viability

International Nuclear Information System (INIS)

Beller, G.

1996-01-01

Identifying preserved myocardial viability in the presence of severe regional left ventricular dysfunction is becoming increasingly more important for clinical decision-making to better select those patients with coronary artery disease who will benefit most from revascularization. 201 Tl remains the most commonly employed radionuclide for detecting both ischemia and viability. A severe persistent defect with 201 Tl uptake compared to peak to improved perfusion and corresponding improved function after revascularisation. Detection of defect reversibility on 201 Tl imaging is enhanced by 'reinjection' of a second 201 Tl dose after acquisition of redistribution images. Initial and 4-hour rest/redistribution imaging has proven most usefull for detection of viability in the resting state in patients with ischemic cardiomyopathy. The greater the extent of preoperative viability, the greater is the improvement in regional and global function after revascularisation. 99 Tc sestamibi has also been demonstrated to be extracted by myocardial cells in proportion to regional blood flow in the presence of viable myocities. Although this agrnt does not redistribute after intravenous injection, its >50% uptake of the tracer implies viablility and predicts improved regional function after revascularisation. Finally positron emission tomography with 18 F fluorodeoxoglucose (FDG) is perhaps the most sensitive noninvasive imaging technique for detection of viability in stunned or hibernating myocardium. A mismatch pattern between regional flow and FDG uptake as approximately an 80-85% positive preicted value for predicting improved function in asynergic myocardial regions after revascualarisation

A serial changes of thallium-201 myocardial images in a patient with nontransmural myocardial infarction

International Nuclear Information System (INIS)

Tanaka, Takeshi; Itoh, Yukiyoshi; Takayama, Yasuo

1986-01-01

A 66 year old man had suffered from inferior myocardial infarction one year ago and then suffered from effort angina. Recently rest angina attack frequently occurred and he was admitted because of angina attack refractory to TNG. The patient was diagnosed as broad nontransmural infarction. A serial thallium-201 myocardial imagings at rest and thallium-201 lung uptake imagings were performed and some interesting findings were obtained as followings. Myocardial imagings on 3rd day after admission showed no significant deffect, however EF was 34 %. Immediately after severe ischemic attack marked defect was noted at posterolateral region and ECG showed prominent precordial ST depression without accompanying significant ST change in II, III, aVF. On 3rd day after severe attack under hemodynamically and electrocardiographically stable state posterolateral defect improved, though still persisted. EF was 28 %. On 3rd day postop no marked defects were noted in myocardial imagings, so posterolateral defect at rest after severe ischemic attack was proved to be transient defect. In this case thallium-201 lung uptake was not noted before attack. Immediately after severe attack thallium lung uptake increased and maximal uptake was noted at basal zone of lung, however in chest X-P typical butterfly shadow was noted at upper zone of lung. On 3rd day after severe attack hemodynamics improved and butterfly shadow ceased, though thallium lung uptake increased and noted at upper zone of lung. After operation thallium lung uptake improved. (J.P.N.)

Temporal Modulation Detection Depends on Sharpness of Spatial Tuning.

Science.gov (United States)

Zhou, Ning; Cadmus, Matthew; Dong, Lixue; Mathews, Juliana

2018-04-25

Prior research has shown that in electrical hearing, cochlear implant (CI) users' speech recognition performance is related in part to their ability to detect temporal modulation (i.e., modulation sensitivity). Previous studies have also shown better speech recognition when selectively stimulating sites with good modulation sensitivity rather than all stimulation sites. Site selection based on channel interaction measures, such as those using imaging or psychophysical estimates of spread of neural excitation, has also been shown to improve speech recognition. This led to the question of whether temporal modulation sensitivity and spatial selectivity of neural excitation are two related variables. In the present study, CI users' modulation sensitivity was compared for sites with relatively broad or narrow neural excitation patterns. This was achieved by measuring temporal modulation detection thresholds (MDTs) at stimulation sites that were significantly different in their sharpness of the psychophysical spatial tuning curves (PTCs) and measuring MDTs at the same sites in monopolar (MP) and bipolar (BP) stimulation modes. Nine postlingually deafened subjects implanted with Cochlear Nucleus® device took part in the study. Results showed a significant correlation between the sharpness of PTCs and MDTs, indicating that modulation detection benefits from a more spatially restricted neural activation pattern. There was a significant interaction between stimulation site and mode. That is, using BP stimulation only improved MDTs at stimulation sites with broad PTCs but had no effect or sometimes a detrimental effect on MDTs at stimulation sites with sharp PTCs. This interaction could suggest that a criterion number of nerve fibers is needed to achieve optimal temporal resolution, and, to achieve optimized speech recognition outcomes, individualized selection of site-specific current focusing strategies may be necessary. These results also suggest that the removal of

Myocardial perfusion imaging in hyperthrophic cardiomyopathy

International Nuclear Information System (INIS)

Moorin, B.

1998-01-01

Full text: Patients with Hyperthrophic Cardiomyopathy (HCM) frequently suffer from syncope and cardiac arrest which may lead to sudden death. This is most often caused by ventricular arrhythmia's in adults, however in young patients the mechanisms are thought to be different. Ischaemia may play a significant role even in young asymptomatic HCM patients. The mechanisms of ischaemic development in HCM differ from those in the 'normal' myocardium (Due to intramural small vessel abnormalities and abnormal myocellular architecture). In HCM the coronary microcirculation is most often affected and massive hypertrophy means more energy is required to promote contraction thus increasing oxygen demand and compounding the effects of any ischaemic changes. A case of a 12 year old HCM patient is presented who has symptoms of syncope associated with exercise whose mother died suddenly of cardiac arrest developed from HCM. A myocardial perfusion rest/stress study was undertaken to detect any underlying myocardial ischaemia. Myocardial perfusion scintigraphy demonstrates any reduction in the microcirculation in addition to that present in the macrocirculation, unlike angiography which will only detect the latter. In this case the scan clearly showed evidence of ischaemia in the lateral wall and this may be an explanation for her episodes of syncope. We suggest an algorithm or the routine work-up of young patients with HCM which makes aggressive use of myocardial perfusion imaging to detect ischaemic changes. This may identify patients who are at higher risk and will assist with treatment decisions. We feel myocardial perfusion scintigraphy is a sensitive non-invasive accurate method of detecting microcirculatory ischaemia and is thus invaluable in HCM patients

Two New Sharp Ostrowski-Grüss Type Inequalities

Directory of Open Access Journals (Sweden)

Zheng Liu

2013-11-01

Full Text Available The purpose of this paper is to use a variant of the Grüss inequality to derive two new sharp Ostrowski-Grüss type inequalities related to a perturbed trapezoidal type rule and a perturbed generalized interior point rule, respectively, which provide improvements of some previous results in the literatures.

CT myocardial perfusion imaging. Ready for prime time?

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