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Sample records for ischemic myocardium minimizing

  1. Substrate use in ischemic and reperfused canine myocardium: quantitative considerations

    International Nuclear Information System (INIS)

    Myears, D.W.; Sobel, B.E.; Bergmann, S.R.

    1987-01-01

    The patterns of use of substrate in reperfused myocardium are not yet well elucidated, and their delineation is essential for adequate interpretation of results of analyses performed after positron emission tomography with labeled substrates to differentiate normal from abnormal heart muscle. Accordingly, in open-chest, anesthetized dogs the authors measured glucose and fatty acid utilization in normal, ischemic, and reperfused myocardium and assessed the contributions of metabolism of each substrate to overall oxidative metabolism. Intracoronary [ 3 H]glucose and [ 14 C]palmitate were administered in five control dogs, eight dogs subjected to 1 h of coronary occlusion, and nine dogs subjected to reperfusion after 1 h of ischemia. Regional coronary venous blood samples were assayed sequentially. In reperfused myocardium, utilization of glucose was 103% greater than that in ischemic and 273% greater than in normal myocardium. Utilization of fatty acid during reperfusion, although greater than that in ischemic myocardium, was significantly less than that in normal myocardium despite restoration of flow to 80% of control values. Despite diminished net uptake of fatty acid, oxidation of fatty acid accounted for 63% of total oxygen consumption in reperfused myocardium. These studies indicate that canine myocardium reperfused after 1 h of ischemia exhibits enhanced uptake of glucose and impaired utilization of palmitate. Nevertheless, palmitate continues to comprise the substrate primarily utilized for oxidative metabolism

  2. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

    International Nuclear Information System (INIS)

    Lipinski, Michael J.; Albelda, M. Teresa; Frias, Juan C.; Anderson, Stasia A.; Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron; Arai, Andrew E.; Epstein, Stephen E.

    2016-01-01

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  3. Multimodality imaging demonstrates trafficking of liposomes preferentially to ischemic myocardium

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    Lipinski, Michael J., E-mail: mjlipinski12@gmail.com [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Albelda, M. Teresa [GIBI2" 3" 0, Grupo de Investigación Biomédica en Imagen, IIS La Fe, Valencia (Spain); Frias, Juan C. [Departamento de Ciencias Biomédicas, Universidad CEU Cardenal Herrera, Valencia (Spain); Anderson, Stasia A. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Luger, Dror; Westman, Peter C.; Escarcega, Ricardo O.; Hellinga, David G.; Waksman, Ron [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States); Arai, Andrew E. [Advanced Cardiovascular Imaging Laboratory, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (United States); Epstein, Stephen E. [MedStar Heart and Vascular Institute, MedStar Washington Hospital Center, Washington, DC (United States)

    2016-03-15

    Introduction: Nanoparticles may serve as a promising means to deliver novel therapeutics to the myocardium following myocardial infarction. We sought to determine whether lipid-based liposomal nanoparticles can be shown through different imaging modalities to specifically target injured myocardium following intravenous injection in an ischemia–reperfusion murine myocardial infarction model. Methods: Mice underwent ischemia–reperfusion surgery and then either received tail-vein injection with gadolinium- and fluorescent-labeled liposomes or no injection (control). The hearts were harvested 24 h later and underwent T1 and T2-weighted ex vivo imaging using a 7 Tesla Bruker magnet. The hearts were then sectioned for immunohistochemistry and optical fluorescent imaging. Results: The mean size of the liposomes was 100 nm. T1-weighted signal intensity was significantly increased in the ischemic vs. the non-ischemic myocardium for mice that received liposomes compared with control. Optical imaging demonstrated significant fluorescence within the infarct area for the liposome group compared with control (163 ± 31% vs. 13 ± 14%, p = 0.001) and fluorescent microscopy confirmed the presence of liposomes within the ischemic myocardium. Conclusions: Liposomes traffic to the heart and preferentially home to regions of myocardial injury, enabling improved diagnosis of myocardial injury and could serve as a vehicle for drug delivery.

  4. Pyrophosphate scan of the temporarily ischemized dog myocardium

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    Duska, F.; Novak, J.; Vizda, J.; Kubicek, J.; Kafka, P.; Veverkova, O.

    1981-12-01

    In 9 dogs a transient myocardial ischemia was provoked using complete occlusion of the ramus interventricularis anterior of the left coronary artery. The occlusion was removed after 5, 10 or 15 min. Four hrs after removal of the occlusion a scan of the myocardium was carried out using sup(99m)Tc-labelled pyrophosphate. In 7 out of 9 dogs under study the scan was markedly positive, in 2 dogs negative. ECG demonstrated ischemic changes practically in all dogs; the changes became normal after removal of the occlusion, namely in 5 to 35 min. The histological examination of the tissue demonstrated in all 9 dogs only a slight impairment of the myocardium.

  5. [The protective action of nimodipine on the ischemic myocardium].

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    Tsorin, I B; Kazanova, G V; Kirsanova, G Iu; Chirkova, E Iu; Chichkanov, G G

    1992-01-01

    The experiments with unconscious cats and dogs have demonstrated that the calcium antagonist nimodipine has a profound anti-ischemic property. The drug reduces the average value of ST-segment elevation in multiple epicardial ECG leads, during acute myocardial ischemia. Nimodipine maintains cardiac pump and contractile functions, elevates ATP levels in the arbitrarily intact and ischemic myocardium of the left ventricle during 40-min occlusion and 60-min reperfusion of the coronary artery. The protective action of the drug is unassociated with enhanced collateral coronary circulation.

  6. Protective Effect of Ischemic Postconditioning against Ischemia Reperfusion-Induced Myocardium Oxidative Injury in IR Rats

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    Jiangwei Ma

    2012-03-01

    Full Text Available Brief episodes of myocardial ischemia-reperfusion (IR employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of ischemic postconditioning on an ischemic reperfusion (IR-induced myocardium oxidative injury in rat model. Results showed that ischemic postconditioning could improve arrhythmia cordis, reduce myocardium infarction and serum creatin kinase (CK, lactate dehydrogenase (LDH and aspartate transaminase (AST activities in IR rats. In addition, ischemic postconditioning could still decrease myocardium malondialdehyde (MDA level, and increased myocardium Na+-K+-ATPase, Ca2+-Mg2+-ATPase, superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GSH-Px and glutathione reductase (GR activities. It can be concluded that ischemic postconditioning possesses strong protective effects against ischemia reperfusion-induced myocardium oxidative injury in IR rats.

  7. Preliminary applied study of assessment ischemic/viable myocardium by 99Tcm-HL91

    International Nuclear Information System (INIS)

    Liu Gang; Wu Hua

    2004-01-01

    Objective: To investigate the representation of 99 Tc m -HL91 in the ischemic myocardium, evaluate the diagnosis value of 99 Tc m -HL91 on hypoxic but viable myocardium. Methods: Six patients with cardiac infarction all underwent 99 Tc m -MIBI SPECT and 99 Tc m -HL91 SPECT. Average radioactivity of ischemic area and normal area were respectively obtained by ROI (2 x 2 pixels) on heart minor axis of images, And the radioactivity ratios of target (ischemic area)-to-non target(normal area)were calculated. Results: In image of 99 Tc m -HL91 SPECT, two patients who's radioactivity coloboma of 99 Tc m -MIBI image could be filled with 99 Tc m -HL91, four patients were not caught sight of obvious filling up. Conclusion 99 Tc m -HL91 can be selectively uptaken by ischemic and hypoxic but viable myocardium. it combination of 99 Tc m -MIBI SPECT may be good for accurate diagnosis and differentiation of viable myocardium. (authors)

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

    International Nuclear Information System (INIS)

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

    1979-01-01

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

  9. 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

  10. Effects of Momordica charantia (Bitter Melon on Ischemic Diabetic Myocardium

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    Attila Czompa

    2017-03-01

    blood of ZO and ZO BM-treated, versus Lean rats of total cholesterol (high density lipoprotein HDL-c + low density lipoprotein LDL-c, with an inferred increase in HDL-c/LDL-c ratio—an outcome associated with decreased risk of atherosclerotic disease. Conclusions: BM extract failed to positively affect T2DM- and cardiovascular-related outcomes at a level suggesting use as a standalone treatment. Nevertheless, the encouraging effects of BM in enhancement of cardiac function, suppression of post-ischemic/reperfused infarct size extent and capacity to modulate serum cholesterol, will likely make it useful as an adjuvant therapy for the management of T2DM and related cardiovascular diseases.

  11. Effects of Momordica charantia (Bitter Melon) on Ischemic Diabetic Myocardium.

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    Czompa, Attila; Gyongyosi, Alexandra; Szoke, Kitti; Bak, Istvan; Csepanyi, Evelin; Haines, David D; Tosaki, Arpad; Lekli, Istvan

    2017-03-20

    and ZO BM-treated, versus Lean rats of total cholesterol (high density lipoprotein HDL-c + low density lipoprotein LDL-c), with an inferred increase in HDL-c/LDL-c ratio-an outcome associated with decreased risk of atherosclerotic disease. Conclusions : BM extract failed to positively affect T2DM- and cardiovascular-related outcomes at a level suggesting use as a standalone treatment. Nevertheless, the encouraging effects of BM in enhancement of cardiac function, suppression of post-ischemic/reperfused infarct size extent and capacity to modulate serum cholesterol, will likely make it useful as an adjuvant therapy for the management of T2DM and related cardiovascular diseases.

  12. Metabolic borderzone in acutely ischemic canine myocardium demonstrated by positron-CT (PCT)

    International Nuclear Information System (INIS)

    Schwaiger, M.; Hansen, H.; Selin, C.; Wittmer, S.; Barrio, J.; Schelbert, H.R.

    1984-01-01

    Acute coronary ligation in dogs results in an area of myocardial dysfunction that exceeds the area of subsequent necrosis suggesting the existence of an ischemic ''borderzone'' of reversibly injured myocardium. The authors tested this hypothesis in 9 closed chest dogs with C-11 plamitate (CPA) and serial PCT imaging after an LAD occlusion. Using a blood flow (MBF) image obtained with iv N-13 ammonia prior to CPA, regions of interest were assigned on the serial CPA cross-sectional images to the center (IC) and border (IB) of the ischemic segment and to control myocardium (CO). CPA uptake was closely related to MBF (r=0.88) implicating flow as a major determinant of CPA uptake. Clearance helftimes (T 1/2) and relative sizes (RS) of the early rapid phase on the C-11 tissue time activity curves were determined for IC, IB and CO. In IC, MBF, RS and T 1/2 were markedly depressed indicating impaired CPA utilization and oxidation. In IB, MBF was less than in CO though only insignificantly, while RS and T 1/2 were highly abnormal. The authors conclude that FFA metabolism in areas adjacent to ischemic segments but without significant MBF decreases in abnormal, presenting evidence for a metabolic borderzone which now can be identified noninvasively with positron emission tomography

  13. Metabolic syndrome impairs notch signaling and promotes apoptosis in chronically ischemic myocardium.

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    Elmadhun, Nassrene Y; Sabe, Ashraf A; Lassaletta, Antonio D; Chu, Louis M; Kondra, Katelyn; Sturek, Michael; Sellke, Frank W

    2014-09-01

    Impaired angiogenesis is a known consequence of metabolic syndrome (MetS); however, the mechanism is not fully understood. Recent studies have shown that the notch signaling pathway is an integral component of cardiac angiogenesis. We tested, in a clinically relevant swine model, the effects of MetS on notch and apoptosis signaling in chronically ischemic myocardium. Ossabaw swine were fed either a regular diet (control [CTL], n = 8) or a high-cholesterol diet (MetS, n = 8) to induce MetS. An ameroid constrictor was placed to induce chronic myocardial ischemia. Eleven weeks later, the wine underwent cardiac harvest of the ischemic myocardium. Downregulation of pro-angiogenesis proteins notch2, notch4, jagged2, angiopoietin 1, and endothelial nitric oxide synthase were found in the MetS group compared with the CTL group. Also, upregulation of pro-apoptosis protein caspase 8 and downregulation of anti-angiogenesis protein phosphorylated forkhead box transcription factor 03 and pro-survival proteins phosphorylated P38 and heat shock protein 90 were present in the MetS group. Cell death was increased in the MetS group compared with the CTL group. Both CTL and MetS groups had a similar arteriolar count and capillary density, and notch3 and jagged1 were both similarly concentrated in the smooth muscle wall. MetS in chronic myocardial ischemia significantly impairs notch signaling by downregulating notch receptors, ligands, and pro-angiogenesis proteins. MetS also increases apoptosis signaling, decreases survival signaling, and increases cell death in chronically ischemic myocardium. Although short-term angiogenesis appears unaffected in this model of early MetS, the molecular signals for angiogenesis are impaired, suggesting that inhibition of notch signaling might underlie the decreased angiogenesis in later stages of MetS. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  14. Change of short-term memory effect in acute ischemic ventricular myocardium: a computational study.

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    Mei, Xi; Wang, Jing; Zhang, Hong; Liu, Zhi-cheng; Zhang, Zhen-xi

    2014-02-01

    The ionic mechanism of change in short-term memory (STM) during acute myocardial ischemia has not been well understood. In this paper, an advanced guinea pig ventricular model developed by Luo and Rudy was used to investigate STM property of ischemic ventricular myocardium. STM response was calculated by testing the time to reach steady-state action potential duration (APD) after an abrupt shortening of basic cycling length (BCL) in the pacing protocol. Electrical restitution curves (RCs), which can simultaneously visualize multiple aspects of APD restitution and STM, were obtained from dynamic and local S1S2 restitution portrait (RP), which consist of a longer interval stimulus (S1) and a shorter interval stimulus (S2). The angle between dynamic RC and local S1S2 RC reflects the amount of STM. Our results indicated that compared with control (normal) condition, time constant of STM response in the ischemic condition decreased significantly. Meanwhile the angle which reflects STM amount is less in ischemic model than that in control model. By tracking the effect of ischemia on intracellular ion concentration and membrane currents, we declared that changes in membrane currents caused by ischemia exert subtle influences on STM; it is only the decline of intracellular calcium concentration that give rise to the most decrement of STM. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Kinetics of Tc-99m hexakis t-butyl isonitrile in normal and ischemic canine myocardium

    International Nuclear Information System (INIS)

    Williams, S.J.; Dragotakos, D.L.

    1989-01-01

    Hexakis 99m Tc-tertiary butyl isonitrile ( 99m Tc-TBI) was studied as a cardiac perfusion imaging agent in nine dogs with partial occlusion of the LAD. Thirty min after applying the stenosis, 99m Tc-TBI was injected into the right atrium (RA) in five dogs and left atrium (LA) in four dogs. Normal and ischemic zone regional myocardial 99m Tc-TBI activities were monitored continuously for 4 h. Dogs with LA injections had minimal and equivalent 4 h fractional clearance from the normal and ischemic zones. Dogs with RA injections had minimal, but significantly lower 4 h fractional 99m Tc clearances in the ischemic zone (0.08±0.08) compared to the normal zone (0.16±0.07, P 99m Tc-TBI a promising cardiac perfusion imaging agent. (orig.)

  16. Fractional flow reserve guided percutaneous coronary intervention results in reduced ischemic myocardium and improved outcomes.

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    Sawant, Abhishek C; Bhardwaj, Aishwarya; Banerjee, Kinjal; Jobanputra, Yash; Kumar, Arnav; Parikh, Parth; Kandregula, Krishna C; Poddar, Kanhaiya; Ellis, Stephen G; Nair, Ravi; Corbelli, John; Kapadia, Samir

    2018-02-06

    To determine if fractional flow reserve guided percutaneous coronary intervention (FFR-guided PCI) is associated with reduced ischemic myocardium compared with angiography-guided PCI. Although FFR-guided PCI has been shown to improve outcomes, it remains unclear if it reduces the extent of ischemic myocardium at risk compared with angiography-guided PCI. We evaluated 380 patients (190 FFR-guided PCI cases and 190 propensity-matched controls) who underwent PCI from 2009 to 2014. Clinical, laboratory, angiographic, stress testing, and major adverse cardiac events [MACE] (all-cause mortality, recurrence of MI requiring PCI, stroke) data were collected. Mean age was 63 ± 11 years; the majority of patients were males (76%) and Caucasian (77%). Median duration of follow up was 3.4 [Range: 1.9, 5.0] years. Procedural complications including coronary dissection (2% vs. 0%, P = .12) and perforation (0% vs. 0%, P = 1.00) were similar between FFR-guided and angiography-guided PCI patients. FFR-guided PCI patients had lower unadjusted (14.7% vs. 23.2%, P = .04) and adjusted [OR = 0.58 (95% CI: 0.34-0.98)] risk of repeat revascularization at one year. FFR-guided PCI patients were less likely (23% vs. 32%, P = .02) to have ischemia and had lower (5.9% vs. 21.1%, P guided PCI, FFR-guided PCI results in less repeat revascularization and a lower incidence of post PCI ischemia translating into improved survival, without an increase in complications. © 2018 Wiley Periodicals, Inc.

  17. Observation of 99Tcm-MIBI uptake of ischemic myocardium in dog models after left circumflex coronary artery constriction

    International Nuclear Information System (INIS)

    Cheng Guanghua; Dai Yunhai; Wu Kefang; Xu Quanfeng

    2008-01-01

    Objective: To observe 99 Tc m -MIBI uptake of ischemic myocardium at different times (1h, 4h) in dog models after left circumflex coronary artery constriction. Methods: 12 dog models of coronary artery stenosis were prepared by left circumflex coronary ligation, and were given injection of 99 Tc m -MIBI at the dosage of 185 MBq (5 mCi). Six models were sacrificed at one hour and four hours after the injection respectively. Radio-uptake in about 100 mg myocardium from both ischemic and non-ischemic sites were measured with r-counter. Results: No significant differences were found between ratios of radioactive count of ischemic over normal myocardial tissues at 1h and 4h after injection of 99 Tc m -MIBI (0.726±0.054 and 0.673±0.080, respective, t=1.3452, P >0.05). Conclusion: The extension of post-injection time would not increase 99 Tc m -MIBI uptake in ischemic myocardium. (authors)

  18. Discrepancy between microsphere and diffusible tracer estimates of perfusion to ischemic myocardium

    International Nuclear Information System (INIS)

    Yoshida, S.; Akizuki, S.; Gowski, D.; Downey, J.M.

    1985-01-01

    This study critically tests the ability of microspheres to accurately measure perfusion to ischemic myocardium. The left anterior descending coronary artery was cannulated and perfused with arterial blood. The perfusion line was clamped, and a sidearm between the clamp and the cannula was opened to the atmosphere, allowing blood to flow retrograde from the distal segment of the artery. Measurement of regional blood flow during retrograde flow diversion with 15-micron microspheres revealed essentially zero flow to the perfused segment (0.005 ml X min-1 X g-1). Measurements under the same conditions by either 86 Rb uptake or 133 Xe washout revealed that an appreciable perfusion of the tissue persisted during retrograde flow diversion (0.043 and 0.11 ml X min-1 X g-1, respectively, for the 2 methods). Thus, the authors have identified a condition during which microspheres indicate zero flow to the tissue but diffusible tracers can both be washed in and washed out at a brisk rate. They conclude that with simple occlusion there is a hidden component of perfusion to an ischemic zone that cannot be measured by microspheres, causing them to underestimate flow by about 25% in that condition

  19. Bone marrow and bone marrow derived mononuclear stem cells therapy for the chronically ischemic myocardium

    International Nuclear Information System (INIS)

    Waksman, Ron; Baffour, Richard

    2003-01-01

    Bone marrow stem cells have been shown to differentiate into various phenotypes including cardiomyocytes, vascular endothelial cells and smooth muscle. Bone marrow stem cells are mobilized and home in to areas of injured myocardium where they are involved in tissue repair. In addition, bone marrow secretes multiple growth factors, which are essential for angiogenesis and arteriogenesis. In some patients, these processes are not enough to avert clinical symptoms of ischemic disease. Therefore, in vivo administration of an adequate number of stem cells would be a significant therapeutic advance. Unfractionated bone marrow derived mononuclear stem cells, which contain both hematopoietic and nonhematopoietic cells may be more appropriate for cell therapy. Studies in animal models suggest that implantation of different types of stem cells improve angiogenesis and arteriogenesis, tissue perfusion as well as left ventricular function. Several unanswered questions remain. For example, the optimal delivery approach, dosage and timing of the administration of cell therapy as well as durability of improvements need to be studied. Early clinical studies have demonstrated safety and feasibility of various cell therapies in ischemic disease. Randomized, double blind and placebo-controlled clinical trials need to be completed to determine the effectiveness of stem cell

  20. Retention and clearance of C-11 palmitic acid in ischemic and reperfused canine myocardium

    International Nuclear Information System (INIS)

    Schwaiger, M.; Schelbert, H.R.; Keen, R.; Vinten-Johansen, J.; Hansen, H.; Selin, C.; Barrio, J.; Huang, S.C.; Phelps, M.E.

    1985-01-01

    Free fatty acids are the major energy source for cardiac muscle. Oxidation of fatty acid decreases or even ceases during ischemia. Its recovery after transient ischemia remains largely unexplored. Using intracoronary carbon-11 palmitic acid as a tracer of myocardial fatty acid metabolism in an open chest dog model, retention and clearance of tracer in myocardium were evaluated at control, during ischemia and after reperfusion following a 20 minute occlusion of the left anterior descending coronary artery. Myocardial C-11 time-activity curves were analyzed with biexponential curve-fitting routines yielding fractional distribution and clearance half-times of C-11 palmitic acid in myocardial tissue. In animals with permanent occlusion and intracoronary injection of C-11 palmitic acid distal to the occlusion site, the relative size and half-time of the early clearance curve component differed markedly from control values and did not change with ongoing ischemia. Conversely, in animals with only 20 minutes of coronary occlusion, the relative size of the early C-11 clearance phase was still significantly depressed at 20 and 90 minutes of reperfusion but returned to control level at 180 minutes. Tissue C-11 clearance half-times remained significantly prolonged throughout the reperfusion period. Regional function in reperfused myocardium monitored with ultrasonic crystals recovered slowly and was still less than control after 3 hours of reperfusion. The data indicate that after transient ischemia, myocardial fatty acid metabolism fails to recover immediately. Because the metabolic recovery occurs in parallel with recovery of regional function, C-11 palmitic acid in conjunction with positron tomography may be useful for studying regional fatty acid metabolism noninvasively after an ischemic injury, and may be helpful in identifying reversible tissue injury

  1. Localization of viable, ischemic myocardium by positron-emission tomography with 11C-palmitate

    International Nuclear Information System (INIS)

    Lerch, R.A.; Ambos, H.D.; Bergmann, S.R.; Welch, M.J.; Ter-Pogossian, M.M.; Sobel, B.E.

    1981-01-01

    A study was performed to determine whether viable, but ischemic, tissue could be detected and localized in vivo based on external detection of impaired fatty acid metabolism. Accordingly, regional clearance of 11 C-palmitate was assessed by sequential PET in 15 anesthetized dogs. Clearance was consistently monoexponential from 5-15 minutes after administration of the tracer. In the absence of coronary stenosis (n = 7), clearance was homogeneous throughout the heart, with an average rate constant (k) of -0.060 +/- 0.005 min -1 (+/- SEM) and a coefficient of variation (CV) of 11.1 +/- 2.1% in each heart. Homogeneity persisted when the heart rate was increased from 84.4 +/- 6.0 to 202.7 +/- 11.5 beats/min with atropine (CV 13.2 +/- 3.5%). With left circumflex coronary stenosis (less than or equal to70% reduction in vessel diameter), homogeneity of 11 C-clearance under control conditions and with tachycardia did not differ from clearance in hearts without coronary stenosis. However, with stenosis >70% sufficient to induce ischemia without gross infarction, regional clearance of 11 C became markedly heterogeneous under control conditions (CV 28.1 +/- 5.5%, p 11 C in regions supplied by the stenotic vessel (k = -0.044 +/- 0.011 min -1 ) compared with clearance in well perfused regions (k = -0.064 +/- 0.011 min -1 , p 11 C-palmitate delineates zones of viable, ischemic myocardium that characteristically exhibit impaired oxidation of extracted fatty acid

  2. Multivariate prediction of spontaneous repetitive responses in ventricular myocardium exposed in vitro to simulated ischemic conditions.

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    Schiariti, M; Puddu, P E; Rouet, R

    1994-06-01

    Guinea-pig ventricular myocardium was partly exposed to normal Tyrode's superfusion and partly to altered conditions (using modified Tyrode's solution) set to simulate acute myocardial ischemia (PO2 80 +/- 10 mmHg; no glucose; pH 7.00 +/- 0.05; K+ 12 mM). Using a double-chamber tissue bath and standard microelectrode technique, the occurrence of spontaneous repetitive responses was investigated during simulated ischemia (occlusion) and after reperfusing the previously ischemic superfused tissue with normal Tyrode's solution (reperfusion). In 62 experiments (42 animals) the effects of: (1) duration of simulated ischemia (1321 +/- 435 s), (2) stimulation rate (1002 +/- 549 ms) and (3) number of successive simulated ischemic periods (occlusions) (1.58 +/- 0.92) on: (1) resting membrane potential, (2) action potential amplitude, (3) duration of 50 and 90% action potentials and (4) maximal upstroke velocity of action potential were studied. All variables were considered as gradients (delta) between normal and ischemic tissue. Both during occlusion and upon reperfusion, spontaneous repetitive responses were coded as single, couplets, salvos (three to nine and > 10) or total spontaneous repetitive responses (coded present when at least one of the above-mentioned types was seen). The incidence of total spontaneous repetitive responses was 31% (19/62) on occlusion and 85% (53/62) upon reperfusion. Cox's models (forced and stepwise) were used to predict multivariately the occurrence of arrhythmic events considered as both total spontaneous repetitive responses and as separate entities. These models were applicable since continuous monitoring of the experiments enabled exact timing of spontaneous repetitive response onset during both occlusion and reperfusion. In predicting reperfusion spontaneous repetitive responses, total spontaneous repetitive responses and blocks observed during the occlusion period were also considered. Total occlusion spontaneous repetitive responses

  3. Enhanced detection of ischemic but viable myocardium by the reinjection of thallium after stress-redistribution imaging

    International Nuclear Information System (INIS)

    Dilsizian, V.; Rocco, T.P.; Freedman, N.M.; Leon, M.B.; Bonow, R.O.

    1990-01-01

    The identification of ischemic but viable myocardium by thallium exercise scintigraphy is often imprecise, since many of the perfusion defects that develop in ischemic myocardium during exercise do not fill in on subsequent redistribution images. We hypothesized that a second injection of thallium given after the redistribution images were taken might improve the detection of ischemic but viable myocardium. We studied 100 patients with coronary artery disease, using thallium exercise tomographic imaging and radionuclide angiography. Patients received 2 mCi of thallium intravenously during exercise, redistribution imaging was performed three to four hours later, and a second dose of 1 mCi of thallium was injected at rest immediately thereafter. The three sets of images (stress, redistribution, and reinjection) were then analyzed. Ninety-two of the 100 patients had exercise-induced perfusion defects. Of the 260 abnormal myocardial regions identified by stress imaging, 85 (33 percent) appeared to be irreversible on redistribution imaging three to four hours later. However, 42 of these apparently irreversible defects (49 percent) demonstrated improved or normal thallium uptake after the second injection of thallium, with an increase in mean regional uptake from 56 +/- 12 percent on redistribution studies to 64 +/- 10 percent on reinjection imaging (P less than 0.001). Twenty patients were restudied three to six months after coronary angioplasty. Of the 15 myocardial regions with defects on redistribution studies that were identified as viable by reinjection studies before angioplasty, 13 (87 percent) had normal thallium uptake and improved regional wall motion after angioplasty. In contrast, all eight regions with persistent defects on reinjection imaging before angioplasty had abnormal thallium uptake and abnormal regional wall motion after angioplasty

  4. Unique Transcriptional Profile of Sustained Ligand-Activated Preconditioning in Pre- and Post-Ischemic Myocardium

    Science.gov (United States)

    Ashton, Kevin J.; Tupicoff, Amanda; Williams-Pritchard, Grant; Kiessling, Can J.; See Hoe, Louise E.; Headrick, John P.; Peart, Jason N.

    2013-01-01

    Background Opioidergic SLP (sustained ligand-activated preconditioning) induced by 3–5 days of opioid receptor (OR) agonism induces persistent protection against ischemia-reperfusion (I-R) injury in young and aged hearts, and is mechanistically distinct from conventional preconditioning responses. We thus applied unbiased gene-array interrogation to identify molecular effects of SLP in pre- and post-ischemic myocardium. Methodology/Principal Findings Male C57Bl/6 mice were implanted with 75 mg morphine or placebo pellets for 5 days. Resultant SLP did not modify cardiac function, and markedly reduced dysfunction and injury in perfused hearts subjected to 25 min ischemia/45 min reperfusion. Microarray analysis identified 14 up- and 86 down-regulated genes in normoxic hearts from SLP mice (≥1.3-fold change, FDR≤5%). Induced genes encoded sarcomeric/contractile proteins (Myh7, Mybpc3,Myom2,Des), natriuretic peptides (Nppa,Nppb) and stress-signaling elements (Csda,Ptgds). Highly repressed genes primarily encoded chemokines (Ccl2,Ccl4,Ccl7,Ccl9,Ccl13,Ccl3l3,Cxcl3), cytokines (Il1b,Il6,Tnf) and other proteins involved in inflammation/immunity (C3,Cd74,Cd83, Cd86,Hla-dbq1,Hla-drb1,Saa1,Selp,Serpina3), together with endoplasmic stress proteins (known: Dnajb1,Herpud1,Socs3; putative: Il6, Gadd45g,Rcan1) and transcriptional controllers (Egr2,Egr3, Fos,Hmox1,Nfkbid). Biological themes modified thus related to inflammation/immunity, together with cellular/cardiovascular movement and development. SLP also modified the transcriptional response to I-R (46 genes uniquely altered post-ischemia), which may influence later infarction/remodeling. This included up-regulated determinants of cellular resistance to oxidant (Mgst3,Gstm1,Gstm2) and other forms of stress (Xirp1,Ankrd1,Clu), and repression of stress-response genes (Hspa1a,Hspd1,Hsp90aa,Hsph1,Serpinh1) and Txnip. Conclusions Protection via SLP is associated with transcriptional repression of inflammation/immunity, up

  5. Unique transcriptional profile of sustained ligand-activated preconditioning in pre- and post-ischemic myocardium.

    Directory of Open Access Journals (Sweden)

    Kevin J Ashton

    Full Text Available BACKGROUND: Opioidergic SLP (sustained ligand-activated preconditioning induced by 3-5 days of opioid receptor (OR agonism induces persistent protection against ischemia-reperfusion (I-R injury in young and aged hearts, and is mechanistically distinct from conventional preconditioning responses. We thus applied unbiased gene-array interrogation to identify molecular effects of SLP in pre- and post-ischemic myocardium. METHODOLOGY/PRINCIPAL FINDINGS: Male C57Bl/6 mice were implanted with 75 mg morphine or placebo pellets for 5 days. Resultant SLP did not modify cardiac function, and markedly reduced dysfunction and injury in perfused hearts subjected to 25 min ischemia/45 min reperfusion. Microarray analysis identified 14 up- and 86 down-regulated genes in normoxic hearts from SLP mice (≥1.3-fold change, FDR≤5%. Induced genes encoded sarcomeric/contractile proteins (Myh7, Mybpc3,Myom2,Des, natriuretic peptides (Nppa,Nppb and stress-signaling elements (Csda,Ptgds. Highly repressed genes primarily encoded chemokines (Ccl2,Ccl4,Ccl7,Ccl9,Ccl13,Ccl3l3,Cxcl3, cytokines (Il1b,Il6,Tnf and other proteins involved in inflammation/immunity (C3,Cd74,Cd83, Cd86,Hla-dbq1,Hla-drb1,Saa1,Selp,Serpina3, together with endoplasmic stress proteins (known: Dnajb1,Herpud1,Socs3; putative: Il6, Gadd45g,Rcan1 and transcriptional controllers (Egr2,Egr3, Fos,Hmox1,Nfkbid. Biological themes modified thus related to inflammation/immunity, together with cellular/cardiovascular movement and development. SLP also modified the transcriptional response to I-R (46 genes uniquely altered post-ischemia, which may influence later infarction/remodeling. This included up-regulated determinants of cellular resistance to oxidant (Mgst3,Gstm1,Gstm2 and other forms of stress (Xirp1,Ankrd1,Clu, and repression of stress-response genes (Hspa1a,Hspd1,Hsp90aa,Hsph1,Serpinh1 and Txnip. CONCLUSIONS: Protection via SLP is associated with transcriptional repression of inflammation/immunity, up

  6. Blood flow, flow reserve, and glucose utilization in viable and nonviable myocardium in patients with ischemic cardiomyopathy.

    Science.gov (United States)

    Zhang, Xiaoli; Schindler, Thomas H; Prior, John O; Sayre, James; Dahlbom, Magnus; Huang, Sung-Cheng; Schelbert, Heinrich R

    2013-04-01

    The aim of the study was to determine whether glucose uptake in viable myocardium of ischemic cardiomyopathy patients depends on rest myocardial blood flow (MBF) and the residual myocardial flow reserve (MFR). Thirty-six patients with ischemic cardiomyopathy (left ventricular ejection fraction 25 ± 10 %) were studied with (13)N-ammonia and (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET). Twenty age-matched normals served as controls. Regional MBF was determined at rest and during dipyridamole hyperemia and regional FDG extraction was estimated from regional FDG to (13)N-ammonia activity ratios. Rest MBF was reduced in viable (0.42 ± 0.18 ml/min per g) and nonviable regions (0.32 ± 0.09 ml/min per g) relative to remote regions (0.68 ± 0.23 ml/min per g, p MFRs did not differ significantly (p > 0.05). Compared to MFR in remote myocardium, MFRs in viable regions were similar (1.39 ± 0.56 vs 1.70 ± 0.45, p > 0.05) but were significantly lower in nonviable regions (1.23 ± 0.43, p MFRs (r =-0.424, p MFRs in viable myocardium are associated with increasing glucose extraction that likely reflects a metabolic adaptation of remodeling hibernating myocytes.

  7. Relationship between iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid washout ratio and oxygen consumption in normal and ischemic myocardium

    International Nuclear Information System (INIS)

    Saito, Kimimasa; Okamoto, Ryuji; Saito, Yasuhiro

    1997-01-01

    The relationship between oxygen consumption and iodine-123-beta-methyl-p-iodophenyl-pentadecanoic acid ( 123 I-BMIPP) washout at rest and after exercise was investigated in normal and ischemic myocardium. Sixteen healthy volunteers and 14 patients with ischemic heart disease were examined. After injection of 111 MBq of 123 I-BMIPP, serial single photon emission computed tomography imaging was performed to evaluate washout ratio after 30 min and 1 hour of rest and after exercise. In the volunteers, the mean washout ratio was 3.3±3.5% after 1 hour of rest and increased during exercise. The exercise washout ratio showed a better correlation with net pressure rate product (net PRP: cumulative values of PRP during exercise) than with the peak PRP. The exercise washout ratio showed a strong correlation with the net PRP in the range from 180 to 300x10 3 mmHg·beat/min and a plateau of 10-15%. In the nine ischemic patients with net PRP≥300x10 3 mmHg·beat/min, the exercise washout ratio values were significantly elevated in normal segments relative to ischemic segments (10.1±1.9% vs 4.7±2.9%, p 3 mmHg·beat/min, washout ratio at rest and after exercise did not differ significantly between normal and ischemic segments. 123 I-BMIPP washout ratio increased with increased oxygen consumption during exercise in normal myocardium but not in ischemic myocardium. The patient must exercise before fatty acid metabolism can be compared between normal and ischemic myocardium. (author)

  8. Experimental Model of Gene Transfection in Healthy Canine Myocardium: Perspectives of Gene Therapy for Ischemic Heart Disease

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    Renato A. K. Kalil

    2002-09-01

    Full Text Available OBJECTIVE: To assess the transfection of the gene that encodes green fluorescent protein (GFP through direct intramyocardial injection. METHODS: The pREGFP plasmid vector was used. The EGFP gene was inserted downstream from the constitutive promoter of the Rous sarcoma virus. Five male dogs were used (mean weight 13.5 kg, in which 0.5 mL of saline solution (n=1 or 0.5 mL of plasmid solution containing 0.5 µg of pREGFP/dog (n=4 were injected into the myocardium of the left ventricular lateral wall. The dogs were euthanized 1 week later, and cardiac biopsies were obtained. RESULTS: Fluorescence microscopy showed differences between the cells transfected and not transfected with pREGFP plasmid. Mild fluorescence was observed in the cardiac fibers that received saline solution; however, the myocardial cells transfected with pREGFP had overt EGFP expression. CONCLUSION: Transfection with the EGFP gene in healthy canine myocardium was effective. The reproduction of this efficacy using vascular endothelial growth factor (VEGF instead of EGFP aims at developing gene therapy for ischemic heart disease.

  9. Angiogenesis with intramyocardial administration of basic fibroblast growth factor in canine ischemic myocardium

    International Nuclear Information System (INIS)

    Sun Lijun; Liu Ying; Zhao Haitao; Huan Yi; Ge Yali; Gao Fabao

    2004-01-01

    Objective: To evaluate the effect of intramyocardial administration of basic fibroblast growth factor on angiogenesis of infarcted myocardium in dogs. Methods: Twenty-four mongrel dogs were randomized into control group and therapeutic group. Acute myocardial infarction was made by ligation of the left anterior descending coronary artery distal to its first diagonal branch. As soon as coronary artery was occluded, 50 mg of basic fibroblast growth factor in 15 ml of saline was injected into the infarcted and border zone in therapeutic group, whereas 15 ml saline alone was used in the same way in control dogs. Every 3 dogs in each group was studied on the 1 st day, the 3 rd day, the 10 th day, and the 17 th day, respectively. Electron microscope was used to observe the growth of capillaries. Angiogenesis was evaluated by immunohistochemical studies with VIII factor. With sensitivity encoded technique, cine MR and MR perfusion imaging were performed on each dog within 3 hours after surgery and before euthanasia to evaluate cardiac function and the characteristics of myocardial perfusion. Results: In therapeutic group, LVEF improved markedly since the 10 th day (on the 10 th day: control group 24.09 ± 3.32, therapeutic group 45.71 ± 6.27; on the 17 th day: control group 31.46 ± 4.60, therapeutic group 53.46 ± 5.24). Hypoenhancement on first pass and hyperenhancement on delayed phase appeared in infarcted myocardium. There were significant differences for the time of upslope, peak time of signal intensity, upslope curves ratio, and contrast enhancement ratio between infarcted and normal myocardium. The size of infarcted myocardium was markedly decreased on the 17 th day [control group (9.04 ± 1.59)%, therapeutic group (4.07 ± 1.20)%]. The capillaries grew actively in therapeutic group and microvessel density was higher in therapeutic group than in control group except the first day (control group and therapeutic group respectively on the 3 rd day: 92.3 ± 11

  10. Segmenting high-frequency intracardiac ultrasound images of myocardium into infarcted, ischemic, and normal regions.

    Science.gov (United States)

    Hao, X; Bruce, C J; Pislaru, C; Greenleaf, J F

    2001-12-01

    Segmenting abnormal from normal myocardium using high-frequency intracardiac echocardiography (ICE) images presents new challenges for image processing. Gray-level intensity and texture features of ICE images of myocardium with the same structural/perfusion properties differ. This significant limitation conflicts with the fundamental assumption on which existing segmentation techniques are based. This paper describes a new seeded region growing method to overcome the limitations of the existing segmentation techniques. Three criteria are used for region growing control: 1) Each pixel is merged into the globally closest region in the multifeature space. 2) "Geographic similarity" is introduced to overcome the problem that myocardial tissue, despite having the same property (i.e., perfusion status), may be segmented into several different regions using existing segmentation methods. 3) "Equal opportunity competence" criterion is employed making results independent of processing order. This novel segmentation method is applied to in vivo intracardiac ultrasound images using pathology as the reference method for the ground truth. The corresponding results demonstrate that this method is reliable and effective.

  11. Intrinsic washout rates of thallium-201 in normal and ischemic myocardium after dipyridamole-induced vasodilation

    International Nuclear Information System (INIS)

    Beller, G.A.; Holzgrefe, H.H.; Watson, D.D.

    1985-01-01

    Infusion of dipyridamole has been suggested as an alternative to exercise stress for myocardial perfusion imaging for detection of ischemia, but the mechanism and significance of thallium-201 ( 201 Tl) redistribution after administration of dipyridamole are uncertain. If disparate intrinsic cellular efflux rates of 201 Tl from normal and relatively underperfused myocardium in response to dipyridamole-induced vasodilation were observed, this could explain delayed 201 Tl redistribution. We investigated the effect of an intravenous infusion of 0.15 mg/kg dipyridamole on the intrinsic myocardial washout rate of 201 Tl as measured with a gamma-detector probe after intracoronary injection (50 muCi) of the radionuclide in open-chested anesthetized dogs. In six normal dogs the t 1/2 for intrinsic 201 Tl washout from the myocardium was 89 +/- 11 min (SE) at control conditions and became more rapid at 59 +/- 10 min (p . .0001) after dipyridamole. This corresponded to a significant increase in microsphere-determined epicardial (0.95 +/- 0.11 to 2.23 +/- 0.46 ml/min/g; p . .01) and endocardial (0.86 +/- 0.10 to 1.53 +/- 0.27; p . .029) flows. In 12 dogs with a critical coronary stenosis, the 201 Tl intrinsic washout rate slowed from 70 +/- 5 to 104 +/- 6 min (p . .0001) after production of the stenosis and slowed even further to 169 +/- 21 min (p . .003) after dipyridamole

  12. Role of the Purkinje-Muscle Junction on the Ventricular Repolarization Heterogeneity in the Healthy and Ischemic Ovine Ventricular Myocardium

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    Marine E. Martinez

    2018-06-01

    Full Text Available Alteration of action potential duration (APD heterogeneity contributes to arrhythmogenesis. Purkinje-muscle junctions (PMJs present differential electrophysiological properties including longer APD. The goal of this study was to determine if Purkinje-related or myocardial focal activation modulates ventricular repolarization differentially in healthy and ischemic myocardium. Simultaneous epicardial (EPI and endocardial (ENDO optical mapping was performed on sheep left ventricular (LV wedges with intact free-running Purkinje network (N = 7. Preparations were paced on either ENDO or EPI surfaces, or the free-running Purkinje fibers (PFs, mimicking normal activation. EPI and ENDO APDs were assessed for each pacing configuration, before and after (7 min of the onset of no-flow ischemia. Experiments were supported by simulations. In control conditions, maximal APD was found at endocardial PMJ sites. We observed a significant transmural APD gradient for PF pacing with PMJ APD = 347 ± 41 ms and EPI APD = 273 ± 36 ms (p < 0.001. A similar transmural gradient was observed when pacing ENDO (49 ± 31 ms; p = 0.005. However, the gradient was reduced when pacing EPI (37 ± 20 ms; p = 0.005. Global dispersion of repolarization was the most pronounced for EPI pacing. In ischemia, both ENDO and EPI APD were reduced (p = 0.005 and the transmural APD gradient (109 ± 55 ms was increased when pacing ENDO compared to control condition or when pacing EPI (p < 0.05. APD maxima remained localized at functional PMJs during ischemia. Local repolarization dispersion was significantly higher at the PMJ than at other sites. The results were consistent with simulations. We found that the activation sequence modulates repolarization heterogeneity in the ischemic sheep LV. PMJs remain active following ischemia and exert significant influence on local repolarization patterns.

  13. Effects of calcium antagonist and free radical scavengers on ischemic and reperfused myocardium due to acute occlusion of coronary arteries

    International Nuclear Information System (INIS)

    Ohsuzu, Fumitaka; Sakata, Nobuhiro; Yanagida, Shigeki

    1988-01-01

    The Langendorff perfused rat heart was used to investigate whether ischemic and reperfused injury could be protected by anti-free radical intervention alone or combined treatment with calcium antagonist. Hearts were subjected to 10 min. of aerobic perfusion with Krebs-Henseleit solution (K-H) and then randomized into three groups (GP): Control group received only K-H, FRS group K-H with superoxide dismutase (24 IU/ml) and catalase (22 IU/ml) and Combined group the same solution of FRS group with verapamil (10'-'7M) for 10 min; and three groups were subjected to 20 min. of global ischemia; and each group was reperfused by the prior perfusate for 20 min. LV developed pressure (DP) and heart rate (HR) were measured by an intraventricular baloon. Phosphorus-31 NMR spectroscopy allowed continuous monitoring of myocardial phosphocreatine (PCr), inorganic phosphate (Pi) and β-ATP content. Each group consisted of 5 experiments. PCr in Combined group was significantly higher than that of Control group with significantly higher values of DP and DPxHR compared to Combined group in the early phase of ischemia. By the middle phase of reperfusion, significant reduction in Pi was found only in Combined group with the reduction of HR. However, no significant difference of β-ATP was found between Control group and Combined group through ischemia and reperfusion. These results suggest that free radical scavengers alone could not protect ischemic and reperfused myocardium from injury, but that the reduction of oxygen consumption by verapamil might be predominantly effective in preventing myocardial damage partially from ischemia and reperfusion. (author)

  14. Metabolic consequences of beta-adrenergic receptor blockade for the acutely ischemic dog myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Westera, G.; Hollander, W. den; Wall, E.E. van der; Eenige, M.J. van; Scholtalbers, S.; Visser, F.C.; Roos, J.P.

    1984-02-01

    In an experimental study in 50 dogs the myocardial uptake of free fatty acids (FFAs) after beta-blockade was determined using radioiodinated heptadecanoic acid as a metabolic tracer. All 4 beta-blockers used (metoprolol, timolol, propranolol and pindolol) lowered the uptake of FFAs in the normal canine heart. Uptake of FFAs was also diminished after coronary artery occlusion per se, but administration of beta-blockers exerted little additional influence on the uptake of FFAs. This observation was qualitatively parallelled by the uptake of /sup 201/Tl in concomitant experiments. Plasma FFA levels were increased by pindolol (non-selective with intrinsic sympathomimetic activity), not changed by metoprolol (a cardioselective betablocking agent) and lowered by timolol and propranolol (both non-selective compounds). The extent of ischemic tissue, as reflected by uptake of iodoheptadecanoic acid and /sup 201/Tl, was diminished by metoprolol but not by other beta-blockers. Regional distribution of both tracers, as shown in the endo-epicardial uptake ratios, was hardly influenced by beta-blockade, except for a small increase of /sup 201/Tl uptake in non-occluded endocardium. Uptake of /sup 201/Tl as well as of iodoheptadecanoic acid in the ischemic area was increased by metoprolol, timolol and propranolol and decreased by pindolol. We conclude that beta-blocking agents confer different effects on myocardial uptake and metabolism of FFAs which might possibly be related to their different inherent properties.

  15. Metabolic consequences of beta-adrenergic receptor blockade for the acutely ischemic dog myocardium

    International Nuclear Information System (INIS)

    Westera, G.; Hollander, W. den; Wall, E.E. van der; Eenige, M.J. van; Scholtalbers, S.; Visser, F.C.; Roos, J.P.

    1984-01-01

    In an experimental study in 50 dogs the myocardial uptake of free fatty acids (FFAs) after beta-blockade was determined using radioiodinated heptadecanoic acid as a metabolic tracer. All 4 beta-blockers used (metoprolol, timolol, propranolol and pindolol) lowered the uptake of FFAs in the normal canine heart. Uptake of FFAs was also diminished after coronary artery occlusion per se, but administration of beta-blockers exerted little additional influence on the uptake of FFAs. This observation was qualitatively parallelled by the uptake of 201 Tl in concomitant experiments. Plasma FFA levels were increased by pindolol (non-selective with intrinsic sympathomimetic activity), not changed by metoprolol (a cardioselective betablocking agent) and lowered by timolol and propranolol (both non-selective compounds). The extent of ischemic tissue, as reflected by uptake of iodoheptadecanoic acid and 201 Tl, was diminished by metoprolol but not by other beta-blockers. Regional distribution of both tracers, as shown in the endo-epicardial uptake ratios, was hardly influenced by beta-blockade, except for a small increase of 201 Tl uptake in non-occluded endocardium. Uptake of 201 Tl as well as of iodoheptadecanoic acid in the ischemic area was increased by metoprolol, timolol and propranolol and decreased by pindolol. We conclude that beta-blocking agents confer different effects on myocardial uptake and metabolism of FFAs which might possibly be related to their different inherent properties. (orig.) [de

  16. Identification of ischemic and hibernating myocardium: feasibility of post-exercise F-18 deoxyglucose positron emission tomography

    International Nuclear Information System (INIS)

    Marwick, T.H.; MacIntyre, W.J.; Salcedo, E.E.; Go, R.T.; Saha, G.; Beachler, A.

    1991-01-01

    The identification of ischemic and hibernating myocardium facilitates the selection of patients most likely to benefit from revascularization. This study examined the feasibility of metabolic imaging, using post-exercise F-18 deoxyglucose positron emission tomography (FDG-PET) for the diagnosis of both ischemia and hibernation in 27 patients with known coronary anatomy. Normal post-exercise FDG uptake was defined in each patient by reference to normal resting perfusion and normal coronary supply. Abnormal elevation of FDG (ischemia or hibernation) was compared in 13 myocardial segments in each patient, with the results of dipyridamole stress perfusion imaging performed by rubidium-82 positron emission tomography (Rb-PET). Myocardial ischemia was diagnosed by either FDG-PET or Rb-PET in 34 segments subtended by significant local coronary stenoses. Increased FDG uptake was present in 32/34 (94%) and a reversible perfusion defect was identified by Rb-PET in 22/34 (65%, p less than .01). In 3 patients, ischemia was identified by metabolic imaging alone. In 16 patients with previous myocardial infarction, perfusion defects were present at rest in 89 regions, 30 of which (34%) demonstrated increased FDG uptake, consistent with the presence of hibernation. Increased post-exercise FDG uptake appears to be a sensitive indicator of ischemia and myocardial hibernation. Increased post-exercise FDG uptake, appears to be a sensitive indicator of ischemia and myocardial hibernation. This test may be useful in selecting post-infarction patients for revascularization

  17. Modulation of ephrinB2 leads to increased angiogenesis in ischemic myocardium and endothelial cell proliferation

    International Nuclear Information System (INIS)

    Mansson-Broberg, Agneta; Siddiqui, Anwar J.; Genander, Maria; Grinnemo, Karl-Henrik; Hao Xiaojin; Andersson, Agneta B.; Waerdell, Eva; Sylven, Christer; Corbascio, Matthias

    2008-01-01

    Eph/ephrin signaling is pivotal in prenatal angiogenesis while its potential role in postnatal angiogenesis largely remains to be explored. Therefore its putative angiogenic and therapeutic effects were explored in endothelium and in myocardial ischemia. In culture of human aortic endothelial cells the fusion protein ephrinB2-Fc induced cell proliferation (p < 0.0005) and in the murine aortic ring model ephrinB2-Fc induced increased sprouting (p < 0.05). Myocardial infarction was induced by ligation of the left anterior descending artery in mouse. During the following 2 weeks mRNA of the receptor/ligand pair EphB4/ephrinB2 was expressed dichotomously (p < 0.05) and other Eph/ephrin pairs were expressed to a lesser degree. Twenty-four hours after intraperitoneal administration of ephrinB2-Fc it was detected in abundance throughout the myocardium along capillaries, showing signs of increased mitosis. After 4 weeks the capillary density was increased 28% in the periinfarcted area (p < 0.05) to a level not different from healthy regions of the heart where no change was observed. These results implicate that EphB4/ephrinB2 is an important signaling pathway in ischemic heart disease and its modulation may induce therapeutic angiogenesis

  18. Prognosis of ischemic heart disease based on pyrophosphate scan of myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F [Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta

    1982-11-01

    A brief survey is given of the present knowledge of the problems, based on literary data. Pyrophosphate myocardial scan is an important examination in establishing the diagnosis of acute myocardial infarction and some other myocardial diseases. Apart from this, it is of great importance in determining the prognosis. In the early phase of the disease, an apparently worse prognosis is found in patients with extensive lesion, and in those with an infarction intensively accumulating the radiopharmaceutical. In a certain number of infarctions, scintigraphic examination is positive over several months; usually the radiopharmaceutical disappears within two weeks. Patients with long-persisting positivity have a markedly worse prognosis. On the basis of early and late heart scan, it is thus possible to estimate the future fate of patients w+th ischemic heart disease. Large and long-persisting lesions serve as a warning for the physician.

  19. Metabolic fate of radiolabeled palmitate in ischemic canine myocardium: implications for positron emission tomography

    International Nuclear Information System (INIS)

    Rosamond, T.L.; Abendschein, D.R.; Sobel, B.E.; Bergmann, S.R.; Fox, K.A.

    1987-01-01

    Interpretation of dynamic and integrated myocardial tomograms requires elucidation of the biochemical fate of the tracer and characterization of its tissue distribution and rate of efflux. The fate of [1- 11 C] and [1- 14 C]palmitate was studied in 13 open-chest dogs during control or ischemic extracorporeal perfusion of the left circumflex coronary artery. Residue detection of myocardial radioactivity, and radio-biochemical analyses of sequential transmural biopsies and arterial and coronary venous effluent were performed for 30 min after intracoronary bolus administration of tracer. In control hearts, 10.3% of initially extracted tracer was retained in tissue (2.9% in triglyceride, 3.5% in phospholipid, and 3.9% in other lipid and aqueous fractions), 73.7% was oxidized, and 16.1% back-diffused unaltered. With ischemia (pump flow 10% of normal), 28.1% was retained (18% in triglyceride, 6.0% in phospholipid, and 4.1% in other lipid and aqueous fractions), 27.2% was oxidized, and 44.4% back diffused (p less than 0.05 compared to control). Throughout the 30-min study interval, triglyceride, diglyceride, and nonesterified fatty acid comprised a significantly greater fraction of initially extracted radioactivity in ischemic than in control hearts. Thus, during ischemia externally detected clearance rates cannot be used as a direct measure of fatty acid metabolism because of marked influences on efflux of nonmetabolized radiolabeled palmitate and the distribution of tracer retained in tissue. Quantitative measurements of specific metabolic processes by tomography will require development and validation of tracers confined to individual metabolic pathways or pools

  20. Pathophysiology and diagnosis of hibernating myocardium in patients with post-ischemic heart failure. The contribution of PET

    International Nuclear Information System (INIS)

    Camici, P.G.; Rimoldi, O.E.

    2003-01-01

    Identification and treatment of hibernating myocardium (HM) lead to improvement in left ventricular (LV) function and prognosis in patients with post-ischemic heart failure. Different techniques are used to diagnose HM: echocardiography, MRI, SPECT and PET and, in patients with moderate LV impairment, their predictive values are similar. There are few data on patients with severe LV dysfunction and heart failure in whom the greatest benefits are apparent after revascularization. Quantification of FDG uptake with PET during hyperinsulinemic euglycemic clamp is accurate in these patients with the greatest mortality risk in whom other techniques may give high false negative rates. The debate on whether resting myocardial blood flow to HM is reduced or not has stimulated new research on heart failure in patients with coronary artery disease. PET with H 2 15 O or 13 NH 3 has been used for the absolute quantification of regional blood flow in human HM. When HM is properly identified, resting blood flow is not different from that in healthy volunteers although a reduction of ∼20% can be demonstrated in a minority of cases. PET studies have shown that the main feature of HM is a severe impairment of coronary vasodilator reserve that improves after revascularization in parallel with LV function. Thus, the pathophysiology of HM is more complex than initially postulated. The recent evidence that repetitive ischemia in patients can be cumulative and lead to more severe and prolonged stunning, lends further support to the hypothesis that, at least initially, stunning and HM are two facets of the same coin. (author)

  1. Low density lipoprotein receptor-related protein 1 expression correlates with cholesteryl ester accumulation in the myocardium of ischemic cardiomyopathy patients

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    Cal Roi

    2012-08-01

    Full Text Available Abstract Our hypothesis was that overexpression of certain lipoprotein receptors might be related to lipid accumulation in the human ischemic myocardium. Intramyocardial lipid overload contributes to contractile dysfunction and arrhythmias in cardiomyopathy. Thus, the purpose of this study was to assess the effect of hypercholesterolemic LDL and hypertrigliceridemic VLDL dose on LRP1 expression in cardiomyocytes, as well as the potential correlation between LRP1 expression and neutral lipid accumulation in the left ventricle tissue from ischemic cardiomyopathy patients. Cell culture experiments include control and LRP1-deficient cardiomyocytes exposed to lipoproteins under normoxic and hypoxic conditions. Explanted hearts from 18 ICM patients and eight non-diseased hearts (CNT were included. Low density lipoprotein receptor-related protein 1 (LRP1, very low density lipoprotein receptor (VLDLR and low density lipoprotein receptor (LDLR expression was analyzed by real time PCR and Western blotting. Cholesteryl ester (CE, triglyceride (TG and free cholesterol (FC content was assess by thin layer chromatography following lipid extraction. Western blotting experiments showed that protein levels of LRP1, VLDLR and HIF-1α were significantly upregulated in ischemic hearts. Immunohistochemistry and confocal microscopy analysis showed that LRP1 and HIF-1α were upregulated in cardiomyocytes of ICM patients. In vitro studies showed that VLDL, LDL and hypoxia exerted an upregulatory effect on LRP1 expression and that LRP1 played a major role in cholesteryl ester accumulation from lipoproteins in cardiomyocytes. Myocardial CE accumulation strongly correlated with LRP1 levels in ischemic hearts. Taken together, our results suggest that LRP1 upregulation is key for myocardial cholesterol ester accumulation in ischemic human hearts and that LRP1 may be a target to prevent the deleterious effects of myocardial cholesterol accumulation in ischemic cardiomyopathy.

  2. [Differential gene expression profile in ischemic myocardium of Wistar rats with acute myocardial infarction: the study on gene construction, identification and function].

    Science.gov (United States)

    Guo, Chun Yu; Yin, Hui Jun; Jiang, Yue Rong; Xue, Mei; Zhang, Lu; Shi, Da Zhuo

    2008-06-18

    To construct the differential genes expressed profile in the ischemic myocardium tissue reduced from acute myocardial infarction(AMI), and determine the biological functions of target genes. AMI model was generated by ligation of the left anterior descending coronary artery in Wistar rats. Total RNA was extracted from the normal and the ischemic heart tissues under the ligation point 7 days after the operation. Differential gene expression profiles of the two samples were constructed using Long Serial Analysis of Gene Expression(LongSAGE). Real time fluorescence quantitative PCR was used to verify gene expression profile and to identify the expression of 2 functional genes. The activities of enzymes from functional genes were determined by histochemistry. A total of 15,966 tags were screened from the normal and the ischemic LongSAGE maps. The similarities of the sequences were compared using the BLAST algebra in NCBI and 7,665 novel tags were found. In the ischemic tissue 142 genes were significantly changed compared with those in the normal tissue (Ppathways of oxidation and phosphorylation, ATP synthesis and glycolysis. The partial genes identified by LongSAGE were confirmed using real time fluorescence quantitative PCR. Two genes related to energy metabolism, COX5a and ATP5e, were screened and quantified. Expression of two functional genes down-regulated at their mRNA levels and the activities of correlative functional enzymes decreased compared with those in the normal tissue. AMI causes a series of changes in gene expression, in which the abnormal expression of genes related to energy metabolism could be one of the molecular mechanisms of AMI. The intervention of the expressions of COX5a and ATP5e may be a new target for AMI therapy.

  3. No evidence for activated autophagy in left ventricular myocardium at early reperfusion with protection by remote ischemic preconditioning in patients undergoing coronary artery bypass grafting.

    Directory of Open Access Journals (Sweden)

    Nilgün Gedik

    Full Text Available Remote ischemic preconditioning (RIPC by repeated brief limb ischemia/reperfusion reduces myocardial injury in patients undergoing coronary artery bypass grafting (CABG. Activation of signal transducer and activator of transcription 5 (STAT5 in left ventricular (LV myocardium at early reperfusion is associated with such protection. Autophagy, i.e., removal of dysfunctional cellular components through lysosomes, has been proposed as one mechanism of cardioprotection. Therefore, we analyzed whether or not the protection by RIPC is associated with activated autophagy.CABG patients were randomized to undergo RIPC (3×5 min blood pressure cuff inflation/5 min deflation or placebo (cuff deflated before skin incision (n = 10/10. Transmural myocardial biopsies were taken from the LV before cardioplegia (baseline and at early (5-10 min reperfusion. RIPC-induced protection was reflected by decreased serum troponin I concentration area under the curve (194±17 versus 709±129 ng/ml × 72 h, p = 0.002. Western blotting for beclin-1-phosphorylation and protein expression of autophagy-related gene 5-12 (ATG5-12 complex, light chain 3 (LC3, parkin, and p62 was performed. STAT3-, STAT5- and extracellular signal-regulated protein kinase 1/2 (ERK1/2-phosphorylation was used as positive control to confirm signal activation by ischemia/reperfusion.Signals of all analyzed autophagy proteins did not differ between baseline and early reperfusion and not between RIPC and placebo. STAT5-phosphorylation was greater at early reperfusion only with RIPC (2.2-fold, p = 0.02. STAT3- and ERK1/2-phosphorylation were greater at early reperfusion with placebo and RIPC (≥2.7-fold versus baseline, p≤0.05.Protection through RIPC in patients undergoing CABG surgery does not appear to be associated with enhanced autophagy in LV myocardium at early reperfusion.

  4. Studies on Tl-201 single photon emission computed tomography (SPECT) of myocardium in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Igarashi, Takeki; Yokoi, Toshio; Ueda, Mitsuru; Horimoto, Masashi; Funayama, Naoki; Takenaka, Takashi; Tasho, Teruo; Tsutsuji, Yuko; Oi, Tsuyoshi

    1985-01-01

    Seventy-six patients with IHD were divided into 2 groups, A) angina pectoris (n=50) and B) previous myocardial infarction(n=26). Each group was classified into three subgroups, without considering hypertension, that is 1) without complication, 2) with hypercholesterolemia, and 3) with diabetes mellitus. We studied and compared the findings of ECG, Echocardiogram (ECHO) and Emission CT (ECT) in these patients at rest. In the previous myocardial infarction group (Group B), we could find 100% ischemic patterns on ECG, 100% asynergy of either IVS or the posterior wall on ECHO and higher percentages of various grade of perfusion defects on ECT compared with group A. In group A, the percentages of perfusion defects were similar in three subgroups. But interestingly, in the hypercholesterolemic group, we could find diffuse moth-eaten like low perfusion areas on ECT. Further study is required whether this finding is peculiar for angina pectoris with hypercholesterolemia or an artifact on ECT. The percentage of ischemic patterns on ECG was lower than in the other groups. In angina pectoris with diabetes mellitus, asynergy in ECHO finding was a significantly higher percentage, compared with other groups. We believe, that ECG, ECHO and ECT are of compensatory importance in the diagnosis of patients with IHD. (author)

  5. Linear relationship between in distribution of thallium-201 and blood flow in ischemic and nonischemic myocardium during exercise

    International Nuclear Information System (INIS)

    Nielsen, A.P.; Morris, K.G.; Murdock, R.; Bruno, F.P.; Cobb, F.R.

    1980-01-01

    The purpose of this study was to compare the myocardial distribution of thallium-201 and regional myocrdial blood flow during ischemia and the physiologic stress of exercise. Studies were carried out in six dogs with chronically implanted catheters in the atrium and aorta and a snare on the circumflex coronary artery distal to the first marginal branch. Regional myocardial blood flow was measured during quiet, resting conditions using 7 to 10 ] of radioisotope-labeled microspheres. Each dog was then exercised on a treadmill at speeds of 5 to 9 mph at a 5/sup o/ incline. (After 1 minute of exercise the cirumflex coronary artery was occluded and thallium-201 and a second label of microspheres were injected. Exercise was continued for 5 minutes. The dogs were then sacrificed and the left ventricle was sectioned into approximately 80 1-2-g samples to compare thallium-201 activity and regional myocardial blood flow. The maximum increase in blood flow ranged from 3.3 to 7.2 times resting control values. Each dog had myocardial samples in which blood flow was markedly reduced, to less than 0.10 ml/min/g. In each dog there was a close linear relationship between thallium-201 distribution and direct measurements of regional myocardial blood flow. Linear regression analyses demonstrated a correlation coefficient of 0.98 or greater in each dog. These data indicate that during the physiologic stress of exercise, the myocardial distribution of thallium activity is linearly related to regional myocardial blood flow in both the ischemic and nonischemic regions

  6. Accumulation of polymorphonuclear leukocytes in reperfused ischemic canine myocardium: relation with tissue viability assessed by fluorine-18-2-deoxyglucose uptake

    International Nuclear Information System (INIS)

    Wijns, W.; Melin, J.A.; Leners, N.

    1988-01-01

    Polymorphonuclear leukocytes may participate in reperfusion injury. Whether leukocytes affect viable or only irreversibly injured tissue is not known. Therefore, we assessed the accumulation of 111In-labeled leukocytes in tissue samples characterized as either ischemic but viable or necrotic by metabolic, histochemical, and ultrastructural criteria. Six open-chest dogs received left anterior descending coronary occlusion for 2 hr followed by 4 hr reperfusion. Myocardial blood flow was determined by microspheres and autologous 111In-labeled leukocytes were injected intravenously. Fluorine-18-2-deoxyglucose, a tracer of exogenous glucose utilization, was injected 3 hr after reperfusion. The dogs were killed 4 hr after reperfusion. The risk and the necrotic regions were assessed following in vivo dye injection and postmortem tetrazolium staining. Myocardial samples were obtained in the ischemic but viable, necrotic and normal zones, and counted for 111In and 18F activity. Compared to normal, leukocytes were entrapped in necrotic regions (111In activity: 207 +/- 73%) where glucose uptake was decreased (26 +/- 15%). A persistent glucose uptake, marker of viability, was mainly seen in risk region (135 +/- 85%) where leukocytes accumulation was moderate in comparison to normal zone (146 +/- 44%). Thus, the glucose uptake observed in viable tissue is mainly related to myocytes metabolism and not to leukocytes metabolism

  7. Minimalism

    CERN Document Server

    Obendorf, Hartmut

    2009-01-01

    The notion of Minimalism is proposed as a theoretical tool supporting a more differentiated understanding of reduction and thus forms a standpoint that allows definition of aspects of simplicity. This book traces the development of minimalism, defines the four types of minimalism in interaction design, and looks at how to apply it.

  8. How to minimize ischemic complication related to swollen temporalis muscle following indirect revascularization surgery in moyamoya disease: a technical report.

    Science.gov (United States)

    Joo, Sung Pil; Kim, Tae Sun; Moon, Hyung Sik

    2014-05-01

    There are several reports in the literature of postoperative ischemic events due to swelling of the temporalis muscle after indirect revascularization surgery. Here, we report our surgical technique for preventing ischemic events during the acute postoperative recovery period in moyamoya patients. We used various types of titanium mesh to cover the bony defect area in 8 patients (10 operations) with moyamoya disease. The mesh was cut and manipulated according to the shape of the bony defect. Surgical results were favorable, with no newly developed ischemic event or infarction in the acute recovery period. The mesh formed an outer table of skull, so there was no compressive effect on the temporalis muscle and no cosmetic defects. The titanium mesh appears to be effective and useful for prevention of ischemic insult in the treatment of moyamoya disease. The choice of this procedure depends on both the operative findings of temporalis muscle thickness and the status of ischemic vulnerability of moyamoya brain. Georg Thieme Verlag KG Stuttgart · New York.

  9. 99mTc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    International Nuclear Information System (INIS)

    Okada, David R.; Liu, Zhonglin; Johnson, Gerald; Okada, Robert D.; Beju, Delia; Khaw, Ban An

    2010-01-01

    99m Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine 99m Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). 99m Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. 99m Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 ± 0.09) (cpm, SEM) than in control (1.74 ± 0.07), stunned (1.68 ± 0.11), and hibernating (1.59 ± 0.11) (p 99m Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 ± 0.63) than in control (1.98 ± 0.15), stunned (1.79 ± 0.08), and hibernating (2.33 ± 0.15) (p 99m Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. 99m Tc-glucarate uptake was strongly correlated with myocardial necrosis as determined by three independent assessments of viability. There were minimal and similar 99m Tc-glucarate uptakes in control, stunned, and hibernating myocardium. (orig.)

  10. {sup 99m}Tc-glucarate kinetics differentiate normal, stunned, hibernating, and nonviable myocardium in a perfused rat heart model

    Energy Technology Data Exchange (ETDEWEB)

    Okada, David R. [University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Liu, Zhonglin [University of Arizona School of Medicine, Tucson, AZ (United States); Johnson, Gerald; Okada, Robert D. [University of Oklahoma Health Sciences Center, Oklahoma, OK (United States); University of Tulsa, Tulsa, OK (United States); Beju, Delia [Oklahoma State University School of Medicine, Tulsa, OK (United States); Khaw, Ban An [Northeastern University, Boston, MA (United States)

    2010-10-15

    {sup 99m}Tc-glucarate is an infarct-avid imaging agent. However, patients may have mixtures of normal, irreversibly injured, stunned, and hibernating myocardium. The purposes were to determine {sup 99m}Tc-glucarate uptake and clearance kinetics in these four conditions, and its ability to determine the extent of injury. Twenty-two perfused rat hearts were studied: controls (n = 5), stunned (n = 5; 20-min no-flow followed by 5-min reflow), hibernating (n = 6; 120-min low flow at 4 ml/min), and ischemic-reperfused (n = 6; 120-min no-flow followed by reflow). {sup 99m}Tc-glucarate was then infused. Tracer activity was monitored using a NaI scintillation detector and a multichannel analyzer. Creatine kinase, electron microscopy, and triphenyltetrazolium chloride determined viability. {sup 99m}Tc-glucarate 10-min myocardial uptake was significantly greater in ischemic-reperfused (2.50 {+-} 0.09) (cpm, SEM) than in control (1.74 {+-} 0.07), stunned (1.68 {+-} 0.11), and hibernating (1.59 {+-} 0.11) (p < 0.05). Tracer retention curves for ischemic-reperfused were elevated at all time points as compared with the other groups. {sup 99m}Tc-glucarate 60-min myocardial uptake was significantly greater in ischemic-reperfused (7.60 {+-} 0.63) than in control (1.98 {+-} 0.15), stunned (1.79 {+-} 0.08), and hibernating (2.33 {+-} 0.15) (p < 0.05). The 60-min well-counted tracer activity ratio of ischemic-reperfused to control was 9:1 and corroborated the NaI detector results. Creatine kinase, triphenyltetrazolium chloride, and electron microscopy all demonstrated significantly greater injury in ischemic-reperfused compared to the other groups. An excellent correlation was observed between viability markers and tracer activity (r = 0.99 triphenyltetrazolium chloride; r = 0.90 creatine kinase). {sup 99m}Tc-glucarate activity continually and progressively increased in irreversibly injured myocardium. {sup 99m}Tc-glucarate uptake was strongly correlated with myocardial necrosis as

  11. Liposome kinetics in infarcted canine myocardium

    International Nuclear Information System (INIS)

    Caride, V.J.; Twickler, J.; Zaret, B.L.

    1984-01-01

    To study the mechanisms and kinetics of liposome deposition in the region of the experimental myocardial infarction, the myocardial distribution of positive and negative liposomes was determined as a function of regional myocardial blood flow and time after administration. The study was performed in dogs at 1 and 24 h following experimental myocardial infarction. Twenty-four hours after coronary artery occlusion, the initial myocardial distribution of positive and negative liposomes (2 min) is directly proportional to regional myocardial blood flow. With time, there is reduction of the radiotracer associated with negative liposomes from all myocardial regions (p less than 0.01). In contrast, in areas of moderate and severe blood flow reduction, there is progressive accumulation of tracers entrapped or incorporated in positive liposomes. This increment becomes significant in 120 min (p less than 0.005). Similar findings are observed in studies performed 1 h after coronary artery occlusion. Dual-label liposomes [( 3 H]cholesterol and [99mTc]diethylenetriamine pentaacetic acid) were used to study the integrity of liposomes in normal and ischemic myocardium. Significant dissociation of the aqueous and lipid labels of positive liposomes is observed 1 h following coronary artery occlusion. In the 24-h myocardial infarction model, dissociation of the aqueous and lipid labels in ischemic myocardium is also observed. This phenomenon is more pronounced with positive than with negative liposomes (p less than 0.02)

  12. Validation of [1-11C]acetate as a tracer for noninvasive assessment of oxidative metabolism with positron emission tomography in normal, ischemic, postischemic, and hyperemic canine myocardium

    International Nuclear Information System (INIS)

    Armbrecht, J.J.; Buxton, D.B.; Schelbert, H.R.

    1990-01-01

    Extraction and clearance kinetics of [1-11C]acetate were examined in 65 experiments in 30 open-chest dogs. Twenty-nine studies were performed at control, 13 during ischemia, eight after reperfusion, 13 during dipyridamole-induced hyperemia, and two during alteration of cardiac workload. [1-11C]acetate was injected directly into the left anterior descending coronary artery, and myocardial tissue-time activity curves were recorded with a gamma probe. The single-pass extraction fraction averaged 64.2 +/- 9.7% in control, 65.3 +/- 9.1% in ischemia, 70.0 +/- 4.4% in reperfusion, and 46.5 +/- 7.4% in dipyridamole-induced hyperemia groups. 11C clearance was biexponential in all cases. The rate constant k1 for the first rapid clearance phase correlated closely with myocardial oxygen consumption (r = 0.94) in control, ischemia, reperfusion, and dipyridamole-induced hyperemia groups. Monoexponential fitting of only the first linear part of the clearance curve yielded the rate constant kmono, which also correlated with myocardial oxygen consumption (r = 0.96). Arterial lactate concentrations and the amount of free fatty acid oxygen equivalents consumed by the myocardium were shown to have a small but statistically significant impact on the relation between [1-11C]acetate clearance rate constants and myocardial oxygen consumption. The fraction of 14CO2 activity contributing to overall 14C activity leaving the myocardium after simultaneous injection of [1-14C]acetate (n = 24) was relatively high in all cases , indicating that externally measured 11C clearance corresponds to CO2 production and thus to tricarboxylic acid cycle activity. In conclusion, the results validate the use of [1-11C]acetate as a tracer of oxidative myocardial metabolism for use with positron emission tomography

  13. Analysis of the influence factors on myocardium to liver ratio of 99Tcm-MIBI

    International Nuclear Information System (INIS)

    Zhang Jinming; Tian Jiahe; Zhao Xiaoguang; Liu Zilai; Wang Shengcai

    1995-01-01

    The resting myocardial SPECT by different MIBI kits for 113 cases of normal and ischemic heart disease is performed. The preparation of kits, reducing agents, and the time of imaging are checked using myocardium to liver (M/L) ratio as the parameter of myocardium uptake of MIBI. It shows that MIBI uptake of myocardium has no relation with the reducing agents, the time of imaging between 60-120 min, while M/L ratio varied in every individual case. The ratio of M/L has also no relation to the Radiochemical Purity (RCP) as long as RCP is more than 95%

  14. Abnormal mitochondrial respiration in failed human myocardium.

    Science.gov (United States)

    Sharov, V G; Todor, A V; Silverman, N; Goldstein, S; Sabbah, H N

    2000-12-01

    Chronic heart failure (HF) is associated with morphologic abnormalities of cardiac mitochondria including hyperplasia, reduced organelle size and compromised structural integrity. In this study, we examined whether functional abnormalities of mitochondrial respiration are also present in myocardium of patients with advanced HF. Mitochondrial respiration was examined using a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles obtained from myocardium of failed explanted human hearts due to ischemic (ICM, n=9) or idiopathic dilated (IDC, n=9) cardiomyopathy. Myocardial specimens from five normal donor hearts served as controls (CON). Basal respiratory rate, respiratory rate after addition of the substrates glutamate and malate (V(SUB)), state 3 respiration (after addition of ADP, V(ADP)) and respiration after the addition of atractyloside (V(AT)) were measured in scar-free muscle bundles obtained from the subendocardial (ENDO) and subepicardial (EPI) thirds of the left ventricular (LV) free wall, interventricular septum and right ventricular (RV) free wall. There were no differences in basal and substrate-supported respiration between CON and HF regardless of etiology. V(ADP)was significantly depressed both in ICM and IDC compared to CON in all the regions studied. The respiratory control ratio, V(ADP)/V(AT), was also significantly decreased in HF compared to CON. In both ICM and IDC, V(ADP)was significantly lower in ENDO compared to EPI. The results indicate that mitochondrial respiration is abnormal in the failing human heart. The findings support the concept of low myocardial energy production in HF via oxidative phosphorylation, an abnormality with a potentially impact on global cardiac performance. Copyright 2000 Academic Press.

  15. Myocardium tracking via matching distributions.

    Science.gov (United States)

    Ben Ayed, Ismail; Li, Shuo; Ross, Ian; Islam, Ali

    2009-01-01

    The goal of this study is to investigate automatic myocardium tracking in cardiac Magnetic Resonance (MR) sequences using global distribution matching via level-set curve evolution. Rather than relying on the pixelwise information as in existing approaches, distribution matching compares intensity distributions, and consequently, is well-suited to the myocardium tracking problem. Starting from a manual segmentation of the first frame, two curves are evolved in order to recover the endocardium (inner myocardium boundary) and the epicardium (outer myocardium boundary) in all the frames. For each curve, the evolution equation is sought following the maximization of a functional containing two terms: (1) a distribution matching term measuring the similarity between the non-parametric intensity distributions sampled from inside and outside the curve to the model distributions of the corresponding regions estimated from the previous frame; (2) a gradient term for smoothing the curve and biasing it toward high gradient of intensity. The Bhattacharyya coefficient is used as a similarity measure between distributions. The functional maximization is obtained by the Euler-Lagrange ascent equation of curve evolution, and efficiently implemented via level-set. The performance of the proposed distribution matching was quantitatively evaluated by comparisons with independent manual segmentations approved by an experienced cardiologist. The method was applied to ten 2D mid-cavity MR sequences corresponding to ten different subjects. Although neither shape prior knowledge nor curve coupling were used, quantitative evaluation demonstrated that the results were consistent with manual segmentations. The proposed method compares well with existing methods. The algorithm also yields a satisfying reproducibility. Distribution matching leads to a myocardium tracking which is more flexible and applicable than existing methods because the algorithm uses only the current data, i.e., does not

  16. Genetic modification of stem cells for improved therapy of the infarcted myocardium.

    Science.gov (United States)

    Haider, Husnain Kh; Mustafa, Anique; Feng, Yuliang; Ashraf, Muhammad

    2011-10-03

    The conventional treatment modalities for ischemic heart disease only provide symptomatic relief to the patient without repairing and regenerating the damaged myocardium. Stem cell transplantation has emerged as a promising alternative therapeutic approach for cardiovascular diseases. Stem cells possess the potential of differentiation to adopt morphofunctional cardiac and vasculogenic phenotypes to repopulate the scar tissue and restore regional blood flow in the ischemic myocardium. These beneficial therapeutic effects make stem cell transplantation the method of choice for the treatment of ischemic heart disease. The efficacy of stem cell transplantation may be augmented by genetic manipulation of the cells prior to transplantation. Not only will insertion of therapeutic transgene(s) into the stem cells support the survival and differentiation of cells in the unfavorable microenvironment of the ischemic myocardium, but also the genetically manipulated stem cells will serve as a source of the transgene expression product in the heart for therapeutic benefits. We provide an overview of the extensively studied stem cell types for cardiac regeneration, the various methods in which these cells have been genetically manipulated and rationale of genetic modification of stem cells for use in regenerative cardiovascular therapeutics.

  17. Capillary transfer constant of Gd-DTPA in the myocardium at rest and during vasodilation assessed by MRI

    DEFF Research Database (Denmark)

    Fritz-Hansen, T; Rostrup, Egill; Søndergaard, Lise

    1998-01-01

    The purpose of this study was to determine whether the capillary transfer constant (Ki) of gadolinium-DTPA was sensitive to perfusion changes and whether ischemic regions in the myocardium could be identified using the modified Kety formula. Ki was measured at rest and during dipyridamole...

  18. Neurogenic Stunned Myocardium Associated with Acute Spinal Cord Infarction: A Case Report

    Directory of Open Access Journals (Sweden)

    Gillian A. Beauchamp

    2012-01-01

    Full Text Available Introduction. Neurogenic stunned myocardium (NSM is a reversible cardiomyopathy resulting in transient left ventricular apical ballooning presumed to result from catecholamine surge occurring under physiologic stress. Acute spinal cord ischemia is a rare ischemic vascular lesion. We report a case of neurogenic stunned myocardium occurring in the setting of acute spinal cord infarction. Methods. Singe case report was used. Results. We present the case of a 63-year-old female with a history of prior lacunar stroke, hypertension, chronic back pain, and hypothyroidism who presented with a brief episode of diffuse abdominal and bilateral lower extremity pain which progressed within minutes to bilateral lower extremity flaccid paralysis. MRI of the spinal cord revealed central signal hyperintensity of T2-weighted imaging from conus to T8 region, concerning for acute spinal cord ischemia. Transthoracic echocardiogram was performed to determine if a cardiac embolic phenomenon may have precipitated this ischemic event and showed left ventricular apical hypokinesis and ballooning concerning for NSM. Conclusion. Neurogenic stunned myocardium is a reversible cardiomyopathy which has been described in patients with physiologic stress resulting in ventricular apical ballooning. Our case suggests that it is possible for neurogenic stunned myocardium to occur in the setting of acute spinal cord ischemia.

  19. Effects of isoproterenol on myocardium

    International Nuclear Information System (INIS)

    Barker, M.E.; Lieber, J.G.; Budinger, T.F.

    1982-01-01

    In the course of autoradiographic studies designed to localize 14 C-taurine within the cells of the rat myocardium, severe tissue damage was noted after stimulation by very low levels of isoproterenol. This β-adrenergic agonist had previously been shown by others to modulate taurine uptake by what appeared to be a very specific mechanism, but our studies have led to a different mechanism. Within four hours after injection of isoproterenol at all concentrations used, pronounced edema of myocytes in the subendocardium was noted; this was followed by an inflammatory reation and degeneration of mitochondria and myofilaments

  20. Anisotropy of the apparent frequency dependence of backscatter in formalin fixed human myocardium.

    Science.gov (United States)

    Hall, C S; Verdonk, E D; Wickline, S A; Perez, J E; Miller, J G

    1997-01-01

    Measurements of the frequency dependence of ultrasonic backscatter are presented for specific angles of insonification for regions of infarcted and noninfarcted human myocardium. A 5-MHz transducer was used to insonify cylindrical cores taken from 7 noninfarcted regions and 12 infarcted regions of the left ventricular free wall of 6 formalin-fixed human hearts explanted because of ischemic cardiomyopathy. The dependence of apparent (uncompensated for diffraction effects and attenuation) backscatter on frequency was approximated by a power-law dependence, magnitude of B(f)2 = afn. Under ideal conditions in a lossless medium, the effect of not compensating for the effects of diffraction and attenuation leads to the value of n to be 2.0 for Rayleigh scatterers while the frequency dependence of the fully compensated backscatter coefficient would be f4. The value of n was determined over the frequency range, 3-7 MHz. Both nonifarcted and infarcted myocardium exhibited anisotropy of the frequency dependence of backscatter, with maxima occurring at angles that were perpendicular to the predominant myofiber direction and minima when parallel to the fibers. Perpendicular insonification yielded results for n of 1.8 +/- 0.1 for noninfarcted myocardium and 1.2 +/- 0.1 for infarcted myocardium while parallel insonification yielded results of 0.4 +/- 0.1 for noninfarcted and 0.0 +/- 0.1 for infarcted myocardium. The functional form of the angle-dependent backscatter is similar for both noninfarcted and infarcted myocardium, although the frequency dependence is clearly different for both tissue states for all angles of insonification. The results of this study indicate that the anisotropy of the frequency dependence of backscatter may play a significant role in ultrasonic imaging and is an important consideration for ultrasonic tissue characterization in myocardium.

  1. Delayed uptake and washout of contrast in non-viable infarcted myocardium shown with dynamic computed tomography

    DEFF Research Database (Denmark)

    Udholm, Sebastian; Laugesen, Sofie; Agger, Peter

    2014-01-01

    BACKGROUND: Assessment of ischemic but potentially viable myocardium plays an important role in the planning of coronary revascularization. Until now SPECT, PET, and MRI have been used to identify viable myocardium. Computed tomography (CT) is increasingly used to diagnose coronary atherosclerosis...... descending artery, followed by removal of the balloon and reperfusion. Four pigs died due to refractory ventricular fibrillation. After 6 weeks, dynamic cardiac CT was performed assessing both wall motion and contrast attenuation. Measurements of attenuation values in Hounsfield units (HU) in the infarct...

  2. Variability and reproducibility of rubidium-82 kinetic parameters in the myocardium of the anesthetized canine

    International Nuclear Information System (INIS)

    Coxson, P.G.; Brennan, K.M.; Huesman, R.H.

    1995-01-01

    Kinetic analysis of 82 Rb (I) dynamic PET data produces quantitative measures which could be used to evaluate ischemic heart disease. These measures have the potential to generate objective comparisons of different patients or the same patient at different times. To achieve this potential, it is essential to determine the variability and reproducibility of the kinetic parameters. A total of 48 I dynamic PET datasets were acquired from two pure bred beagles. Each animal underwent eight I PET studies with essentially the same protocol for three successive weeks. Data were acquired with the Donner 600-Crystal Positron Tomograph (PET600). In each week, single-slice dynamic I PET datasets were collected with the animal at rest at three different gantry positions separated by 5 mm. Additional dataset were collected after dipyridamole infusion and after administration of aminophylline to induce a return to rest. A two-compartment kinetic model with correction for myocardial vasculature and spillover from the left ventricular blood pool was used to analyze the dynamic datasets. Model parameters for uptake (k 1 ), washout (k 2 ) and vascular fraction (f v ) were estimated in 11-14 myocardial regions of interest (ROIs) using a weighted least-squares criterion. Statistical fluctuation due to the PET acquisition process was minimized by using a relatively high I dose (about 30 mCi) to take advantage of the high count rate capacity of the PET600. The variation in mean k 1 , where the mean is taken over the myocardial ROIs was 10%-20% (Dog 1) and 15%-50% (Dog 2) among the rest studies conducted on the same data. Similar variation was evident in comparing studies in the same animal for different weeks. Spatial and temporal variation in estimates of the uptake rate (k 1 ) of I in the resting myocardium of the anesthetized canine are small in relation to the functional increase in k 1 , following dipyridamole stress. 17 refs., 14 figs

  3. Kronisk iskaemisk hjerteinsufficiens. Revaskularisering bedrer overlevelsen blandt patienter med hibernating myocardium

    DEFF Research Database (Denmark)

    Holdgaard, Paw Chr; Nielsen, Søren Steen; Wiggers, Henrik

    2007-01-01

    imaging was performed with 99mTc-sestamibi and glucose metabolism was visualized with 18F-fluorodeoxyglucose (18F-FDG) gamma camera PET. Medical records and death certificate were reviewed retrospectively. RESULTS: 50 patients were included. We found an increased survival among patients with HIB who......INTRODUCTION: Patients with ischemic heart failure and reversible dysfunctional myocardium (Hibernating myocardium, HIB) can benefit from revascularization. These patients can be selected with nuclear methods. The purpose of this study was to describe the results of the imaging procedures...... in patients tested for HIB and relate the results to the choice of treatment and cause of death. MATERIALS AND METHODS: During a 2-year period 51 patients were referred to determine the amount of HIB. This can be determined with blood flow and metabolic imaging of the heart. Resting-myocardial perfusion...

  4. Study on the kinetics of high-energy phosphates in myocardium by phosphorous nuclear magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Kusuoka, Hideo; Tsuneoka, Yutaka; Inoue, Michitoshi; Abe, Hiroshi [Osaka Univ. (Japan). Faculty of Medicine; Watari, Hiroshi

    1982-12-01

    Effect of artificial blood, FC 43 (Perfluorochemicals) on the kinetics of high-energy phosphate in the myocardium was evaluated by /sup 31/P-NMR which permits a continuous and non-invasive assessment of in vivo phosphorus compounds. Cardiac perfusion was carried out on a excised rat heart with a Krebs-Henseleit modified solution and FC 43 alternately. Under the normal condition, ischemic condition, and at second perfusion amounts of intramyocardial creatine phosphoric acid, ATP, and inorganic phosphorus were determined by /sup 31/P-NMR. Coronary flow was simultaneously estimated. The ischemic state due to interruption of perfusion resulted in a decrease in creatine phosphoric acid, which was associated with an increase in inorganic phosphorus and intracellular acidosis. No change of ATP amount was observed under ischemic state. With resumption of perfusion, the levels of creatine phosphoric acid and inorganic phosphorus rapidly returned to the normal. In the group of FC 43, coronary flow was 2.68 ml/min/g of the heart weight, about 1/2 of that of the Krebs-Henseleit group (5.68 ml/min/g of the heart weight). In controls, there was no difference between the two groups concerning creatine phosphoric acid level and recovery of creatine phospohric acid level after ischemia. These results showed that FC 43 supplies sufficient oxygen, and has no effect on the kinetics of energy in the myocardium.

  5. Imaging of the myocardium using {sup 18}F-FDG-PET/MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ferda, Jiří, E-mail: ferda@fnplzen.cz [Clinic of the Imaging Methods, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Hromádka, Milan, E-mail: hromadkam@fnplzen.cz [Department of Cardiology, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Baxa, Jan, E-mail: baxaj@fnplzen.cz [Clinic of the Imaging Methods, University Hospital Plzen, Alej Svobody 80, 304 60 Plzeň (Czech Republic)

    2016-10-15

    Highlights: • The natural combination of the metabolic and structural information is the most important strenghtof myocardial PET/MRI. • Metabolic conversion to glycolysis is needed in the assesment ov the viable myocardium. • Metabolic conversion to the fatty acid metabolism is the crucial in the assesment of the ischemic memory and myocardial inflammation. - Abstract: The introduction of the integrated hybrid PET/MRI equipment creates the possibility to perform PET and MRI simultaneously. Depending on the clinical question, the metabolic conversion to glycolytic activity or beta-oxidation is performed before the application of FDG. Since FDG aids to evaluate the energetic metabolism of the myocytes and myocardial MRI reaches the imaging capabilities of perfusion and tissue characterization in the daily routine, FDG-PET/MRI looks to be a promising method of PET/MRI exploitation in cardiac imaging. When myocardial FDG uptake should be evaluated in association with the perfusion distribution, the cross-evaluation of FDG accumulation distribution and perfusion distribution pattern is necessary. The different scenarios may be used in the assessment of myocardium, the conversion to glycolytic activity is used in the imaging of the viable myocardium, but the glycolytic activity suppression might be used in the indications of the identification of injured myocardium by ischemia or inflammation. FDG-PET/MRI might aid to answer the clinical tasks according to the structure, current function and possibilities to improve the function in ischemic heart disease or to display the extent or activity of myocardial inflammation in sarcoidosis. The tight coupling between metabolism, perfusion and contractile function offers an opportunity for the simultaneous assessment of cardiac performance using one imaging modality.

  6. TOWARD THE QUESTION OF ISCHEMIC MYOCARDIAL DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    V. V. Kalyuzhin

    2014-01-01

    Full Text Available The authors of the review have analyzed papers published on the problem of ischemic myocardial dysfunction. They begin with a definition of the term “ischemia” (derived from two Greek words: ischō, meaning to hold back, and haima, meaning blood - a condition at which the arterial blood flow is insufficient to provide enough oxygen to prevent intracellular respiration from shifting from the aerobic to the anaerobic form. The poor rate of ATP generation from this process causes a decrease in cellular ATP, a concomitant rise in ADP, and ultimately, to depression inotropic (systolic and lusitropic (diastolic function of the affected segments of the myocardium. But with such simplicity of basic concepts, the consequences of ischemia so diverse. Influence of an ischemia on myocardial function so unequally at different patients, which is almost impossible to find two identical cases (as in the case of fingerprints. It depends on the infinite variety of lesions of coronary arteries, reperfusion (time and completeness of restoration of blood flow and reactions of a myocardium which, apparently, has considerable flexibility in its response. Ischemic myocardial dysfunction includes a number of discrete states, such as acute left ventricular failure in angina, acute myocardial infarction, ischemic cardiomyopathy, stunning, hibernation, pre- and postconditioning. There are widely differing underlying pathophysiologic states. The possibility exists that several of these states can coexist.

  7. Detection of the myocardium ischemia in scintigraphy

    International Nuclear Information System (INIS)

    Faraggi, M.; Pierquet-Ghazzar, N.; Maunoury, C.

    2005-01-01

    The myocardium scintigraphy (SPECT) gives excellent elements of prognosis allowing to select at the best, the patients having a revascularization, and then an angiography examination. It appears complementary of the coronaries tree imaging and should (in theory) be practised in first in an organisation chart of taking over. In the search of practicable myocardium, the PET with 18 FDG, although being competitive, is more and more forsaken to the MRI profit. In retaliation, the PET with 82 Rb with test of pharmacology stimulation could develop in detection of coronaries disease. (N.C.)

  8. Myocardium at risk assessed by electrocardiographic scores and cardiovascular magnetic resonance - a MITOCARE substudy

    DEFF Research Database (Denmark)

    Sejersten, Maria; Fakhri, Yama; Pape, Marianne

    2017-01-01

    Introduction The myocardium at risk (MaR) represents the quantitative ischemic area destined to myocardial infarction (MI) if no reperfusion therapy is initiated. Different ECG scores for MaR have been developed, but there is no consensus as to which should be preferred. Objective Comparisons...... of ECG scores and Cardiac Magnetic Resonance (CMR) for determining MaR. Methods MaR was determined by 3 different ECG scores, and by CMR in ST-segment elevation MI (STEMI) patients from the MITOCARE cardioprotection trial. The Aldrich score (AL) is based on the number of leads with ST-elevation...... for anterior MI and the sum of ST-segment elevation for inferior MI on the admission ECG. The van Hellemond score (VH) considers both the ischemic and infarcted component of the MaR by adding the AL and the QRS score, which is an estimate of final infarct size. The Hasche score is based on the maximal possible...

  9. Ventricular tachycardia in ischemic heart disease substrates

    Directory of Open Access Journals (Sweden)

    Olujimi A. Ajijola

    2014-01-01

    This review will discuss the central role of the ischemic heart disease substrate in the development MMVT. Electrophysiologic characterization of the post-infarct myocardium using bipolar electrogram amplitudes to delineate scar border zones will be reviewed. Functional electrogram determinants of reentrant circuits such as isolated late potentials will be discussed. Strategies for catheter ablation of reentrant ventricular tachycardia, including structural and functional targets will also be examined, as will the role of the epicardial mapping and ablation in the management of recurrent MMVT.

  10. Detection of viable myocardium in canine model with myocardial ischemia and ischemia-reperfusion by 125I-BMIPP: relation to regional blood flow

    International Nuclear Information System (INIS)

    Huang Gang; Zhao Huiyang; Shen Xuedong; Li Qing; Yuan Jimin; Zhu Cuiying

    1999-01-01

    Objective: The effects of BMIPP (β-methyl-iodophenyl pentadecanoic acid) on detecting viable myocardium and the relation between regional blood flow and the uptake of BMIPP were evaluated in canine model of myocardial ischemia and ischemia-reperfusion. Methods: 12 open-chest dogs under anesthesia were divided into two groups. Group I (ischemia group) had left circumflex coronary arterial occlusion for 2 h and group II (ischemia-reperfusion group) was occluded for 1 h and followed by 2 h reperfusion. Myocardial blood flow was measured with 99 Tc m -microspheres. 30 min after intravenous injection of 125 I-BMIPP and 99 Tc m -microspheres, the heart was excised rapidly and stained with Evans blue and NBT. Tissue samples (divided into approximately 1 g) of left ventricle were obtained, weighed and counted for 125 I and 99 Tc m . Regional blood flow and the uptake of BMIPP were expressed as percentages of average values in non-ischemic myocardium (two to three tissue samples) from the normal myocardium. Results: In ischemic myocardium (NBT positive samples), the uptake of BMIPP was relatively higher compared with regional blood flow [(67 +- 23)% vs (42 +- 19)%, P 0.05]. In ischemia-reperfusion group, regional blood flow was increased in ischemic and necrotic tissues, but the uptake of BMIPP was not enhanced with the increasing blood flow. Conclusions: BMIPP uptake seems to provide metabolic information independent of regional blood flow. The mismatching between regional blood flow and BMIPP uptake may indicate myocardial viability in the regions of hypoperfusion and the uptake of BMIPP in ischemic myocardium was related to existence of cellular metabolism

  11. Genetic modification of mesenchymal stem cells overexpressing CCR1 increases cell viability, migration, engraftment, and capillary density in the injured myocardium.

    Science.gov (United States)

    Huang, Jing; Zhang, Zhiping; Guo, Jian; Ni, Aiguo; Deb, Arjun; Zhang, Lunan; Mirotsou, Maria; Pratt, Richard E; Dzau, Victor J

    2010-06-11

    Although mesenchymal stem cell (MSC) transplantation has been shown to promote cardiac repair in acute myocardial injury in vivo, its overall restorative capacity appears to be restricted mainly because of poor cell viability and low engraftment in the ischemic myocardium. Specific chemokines are upregulated in the infarcted myocardium. However the expression levels of the corresponding chemokine receptors (eg, CCR1, CXCR2) in MSCs are very low. We hypothesized that this discordance may account for the poor MSC engraftment and survival. To determine whether overexpression of CCR1 or CXCR2 chemokine receptors in MSCs augments their cell survival, migration and engraftment after injection in the infarcted myocardium. Overexpression of CCR1, but not CXCR2, dramatically increased chemokine-induced murine MSC migration and protected MSC from apoptosis in vitro. Moreover, when MSCs were injected intramyocardially one hour after coronary artery ligation, CCR1-MSCs accumulated in the infarcted myocardium at significantly higher levels than control-MSCs or CXCR2-MSCs 3 days postmyocardial infarction (MI). CCR1-MSC-injected hearts exhibited a significant reduction in infarct size, reduced cardiomyocytes apoptosis and increased capillary density in injured myocardium 3 days after MI. Furthermore, intramyocardial injection of CCR1-MSCs prevented cardiac remodeling and restored cardiac function 4 weeks after MI. Our results demonstrate the in vitro and in vivo salutary effects of genetic modification of stem cells. Specifically, overexpression of chemokine receptor enhances the migration, survival and engraftment of MSCs, and may provide a new therapeutic strategy for the injured myocardium.

  12. Sustained nonoxidative glucose utilization and depletion of glycogen in reperfused canine myocardium

    International Nuclear Information System (INIS)

    Schwaiger, M.; Neese, R.A.; Araujo, L.

    1989-01-01

    Ischemically injured reperfused myocardium is characterized by increased 18F-fluorodeoxyglucose uptake as demonstrated by positron emission tomography. To elucidate the metabolic fate of exogenous glucose entering reperfused myocardium, D-[6-14C] glucose and L-[U-13C] lactate were used to determine glucose uptake, glucose oxidation and the contribution of exogenous glucose to lactate production. The pathologic model under investigation consisted of a 3 h balloon occlusion of the left anterior descending coronary artery followed by 24 h of reperfusion in canine myocardium. The extent and severity of myocardial injury after the ischemia and reperfusion were assessed by histochemical evaluation (triphenyltetrazolium chloride and periodic acid-Schiff stains). Thirteen intervention and four control dogs were studied. The glucose uptake in the occluded/reperfused area was significantly enhanced compared with that in control dogs (0.40 +/- 0.14 versus 0.15 +/- 0.10 mumol/ml, respectively). In addition, a significantly greater portion of the glucose extracted immediately entered glycolysis in the intervention group (75%) than in the control dogs (33%). The activity of the nonoxidative glycolytic pathway was markedly increased in the ischemically injured reperfused area, as evidenced by the four times greater lactate release in this area compared with the control value. The dual carbon-labeled isotopes showed that 57% of the exogenous glucose entering glycolysis was being converted to lactate. Exogenous glucose contributed to greater than 90% of the observed lactate production. This finding was confirmed by the histochemical finding of sustained glycogen depletion in the occlusion/reperfusion area. The average area of glycogen depletion (37%) significantly exceeded the average area of necrosis

  13. A Review of Neurogenic Stunned Myocardium

    OpenAIRE

    Biso, Sylvia; Wongrakpanich, Supakanya; Agrawal, Akanksha; Yadlapati, Sujani; Kishlyansky, Marina; Figueredo, Vincent

    2017-01-01

    Neurologic stunned myocardium (NSM) is a phenomenon where neurologic events give rise to cardiac abnormalities. Neurologic events like stroke and seizures cause sympathetic storm and autonomic dysregulation that result in myocardial injury. The clinical presentation can involve troponin elevation, left ventricular dysfunction, and ECG changes. These findings are similar to Takotsubo cardiomyopathy and acute coronary syndrome. It is difficult to distinguish NSM from acute coronary syndrome bas...

  14. Prolonged ischemic heart disease and coronary artery bypass - relation to contractile reserve

    DEFF Research Database (Denmark)

    Kofoed, Klaus F; Bangsgaard, Regitze; Carstensen, Steen

    2002-01-01

    OBJECTIVE: A major effect of coronary artery bypass grafting (CABG) in patients with ischemic heart disease and impaired left ventricular (LV) contractile function is believed to be an improvement in LV function due to recovery of dysfunctional, but viable myocardium. However, recent studies have...

  15. Collateral circulation as a marker of the presence of viable myocardium in patients with recent myocardial infarction

    International Nuclear Information System (INIS)

    Fujita, M.; Ohno, A.; Wada, O.; Miwa, K.; Nozawa, T.; Yamanishi, K.; Sasayama, S.

    1991-01-01

    The relationship between the presence of viable myocardium and the extent of coronary collateral circulation to the infarct area was evaluated in 20 patients with a recent anterior myocardial infarction who had complete obstruction of the left anterior descending coronary artery. The viability of myocardial tissue was assessed by exercise thallium-201 myocardial scintigraphy, and the collateral circulation was angiographically evaluated by means of a collateral index ranging from 0 to 3. Patients were divided into two groups according to the presence (group 1, n = 10) or absence (group 2, n = 10) of viable myocardium in the perfusion territory of the infarct-related artery. The collateral index in group 1 was 2.5 ± 0.5 (SD), which was significantly higher than the 0.7 ± 0.8 in group 2. These findings indicate that the presence of ischemic but viable myocardium is intimately related to the development of collateral circulation in patients with myocardial infarction, and the existence of well-developed collateral channels predicts the presence of viable myocardium in the infarct area

  16. Backscatter and attenuation characterization of ventricular myocardium

    Science.gov (United States)

    Gibson, Allyson Ann

    2009-12-01

    This Dissertation presents quantitative ultrasonic measurements of the myocardium in fetal hearts and adult human hearts with the goal of studying the physics of sound waves incident upon anisotropic and inhomogeneous materials. Ultrasound has been used as a clinical tool to assess heart structure and function for several decades. The clinical usefulness of this noninvasive approach has grown with our understanding of the physical mechanisms underlying the interaction of ultrasonic waves with the myocardium. In this Dissertation, integrated backscatter and attenuation analyses were performed on midgestational fetal hearts to assess potential differences in the left and right ventricular myocardium. The hearts were interrogated using a 50 MHz transducer that enabled finer spatial resolution than could be achieved at more typical clinical frequencies. Ultrasonic data analyses demonstrated different patterns and relative levels of backscatter and attenuation from the myocardium of the left ventricle and the right ventricle. Ultrasonic data of adult human hearts were acquired with a clinical imaging system and quantified by their magnitude and time delay of cyclic variation of myocardial backscatter. The results were analyzing using Bayes Classification and ROC analysis to quantify potential advantages of using a combination of two features of cyclic variation of myocardial backscatter over using only one or the other feature to distinguish between groups of subjects. When the subjects were classified based on hemoglobin A1c, the homeostasis model assessment of insulin resistance, and the ratio of triglyceride to high-density lipoprotein-cholesterol, differences in the magnitude and normalized time delay of cyclic variation of myocardial backscatter were observed. The cyclic variation results also suggested a trend toward a larger area under the ROC curve when information from magnitude and time delay of cyclic variation is combined using Bayes classification than when

  17. A study on the kinetics of high-energy phosphates in myocardium by phosphorous nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Kusuoka, Hideo; Tsuneoka, Yutaka; Inoue, Michitoshi; Abe, Hiroshi; Watari, Hiroshi.

    1982-01-01

    Effect of artificial blood, FC 43 (Perfluorochemicals) on the kinetics of high-energy phosphate in the myocardium was evaluated by 31 P-NMR which permits a continuous and non-invasive assessment of in vivo phosphorus compounds. Cardiac perfusion was carried out on a excised rat heart with a Krebs-Henseleit modified solution and FC 43 alternately. Under the normal condition, ischemic condition, and at second perfusion amounts of intramyocardial creatine phosphoric acid, ATP, and inorganic phosphorus were determined by 31 P-NMR. Coronary flow was simultaneously estimated. The ischemic state due to interruption of perfusion resulted in a decrease in creatine phosphoric acid, which was associated with an increase in inorganic phosphorus and intracellular acidosis. No change of ATP amount was observed under ischemic state. With resumption of perfusion, the levels of creatine phosphoric acid and inorganic phosphorus rapidly returned to the normal. In the group of FC 43, coronary flow was 2.68 ml/min/g of the heart weight, about 1/2 of that of the Krebs-Henseleit group (5.68 ml/min/g of the heart weight). In controls, there was no difference between the two groups concerning creatine phosphoric acid level and recovery of creatine phospohric acid level after ischemia. These results showed that FC 43 supplies sufficient oxygen, and has no effect on the kinetics of energy in the myocardium. (Ueda, J.)

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

    International Nuclear Information System (INIS)

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

    1982-01-01

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

  19. Fatty acid uptake and turnover rate in the ischemic before and after bypass surgery

    International Nuclear Information System (INIS)

    Freundlieb, C.; Hoeck, A.; Vyska, K.; Erbel, R.; Feinendegen, L.E.

    1982-01-01

    17-123-Iodo-heptadecanoic acid (IHA) turnover in myocardium signals myocardial metabolism of free fatty acids. Thus, it appeared promising to examine the influence of cardiovascular surgery on coronary perfusion and on the metabolic state of the ischemic myocardium by use of IHA. The data show that IHA uptake and elimination are two separate parameters which may be changed in the ischemic heart. The two parameters do not necessarily change in parallel. In ischemic heart disease at rest a normal IHA accumulation pattern may be associated with altered regional IHA turnover rates. On the other hand also accumulation defects without changes in IHA turnover rate were observed. Although the relationship between IHA uptake and turnover is not yet sufficiently understood that statements about the indication and prognosis of bypass surgery can be derived

  20. Ischemic preconditioning protects against ischemic brain injury

    Directory of Open Access Journals (Sweden)

    Xiao-meng Ma

    2016-01-01

    Full Text Available In this study, we hypothesized that an increase in integrin αv ß 3 and its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αv ß 3, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αv ß 3 and vascular endothelial growth factor levels in the brain following ischemia.

  1. Clinical effect of Dilazep on ischemic heart disease

    International Nuclear Information System (INIS)

    Tsuda, Takashi; Hayashi, Senji; Shibata, Akira; Hama, Hitoshi; Mitani, Tohru.

    1982-01-01

    Dilazep tablets (300 mg/day) were administered to 9 patients with ischemic heart disease for more than 2 months. Stress myocardial scintigraphy was performed before and after the treatment to examine the clinical effect of this drug on the heart. The improvement rate of subjective symptoms was 57% (4/7 cases). No significant difference was observed in double product by the ergometer before and after the treatment, nor were any significant changes observed in ST by Master's two-step exercise test in any patient. The pre- to posttreatment improvement rate of myocardial uptake, demonstrated by stress myocardial scintigraphy, was 89% (8/9 cases). Thus, Dilazep tablets seemed to increase the blood flow in the ischemic area of the myocardium during exercise in ischemic heart disease. (Chiba, N.)

  2. miRNAs as therapeutic targets in ischemic heart disease.

    Science.gov (United States)

    Frost, Robert J A; van Rooij, Eva

    2010-06-01

    Ischemic heart disease is a form of congestive heart failure that is caused by insufficient blood supply to the heart, resulting in a loss of viable tissue. In response to the injury, the non-ischemic myocardium displays signs of secondary remodeling, like interstitial fibrosis and hypertrophy of cardiac myocytes. This remodeling process further deteriorates pump function and increases susceptibility to arrhythmias. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression in a sequence-dependent manner. Recently, several groups identified miRNAs as crucial gene regulators in response to myocardial infarction (MI) and during post-MI remodeling. In this review, we discuss how modulation of these miRNAs represents a promising new therapeutic strategy to improve the clinical outcome in ischemic heart disease.

  3. Tropical diseases of the myocardium: a review

    Directory of Open Access Journals (Sweden)

    Groom ZC

    2017-04-01

    Full Text Available Zoe C Groom,1 Aristotle D Protopapas,2 Vasileios Zochios3,4 1Costello Medical Consulting Limited, Cambridge, 2Department of Surgery, Division of Surgery and Cancer, Imperial College London, London, 3Department of Intensive Care Medicine, Queen Elizabeth Hospital Birmingham, University Hospitals Birmingham NHS Foundation Trust, 4College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK Abstract: Cardiovascular diseases are widely distributed throughout the world. Human parasitic infections are ubiquitous. Tropical parasites are increasingly recognized as causes of cardiovascular diseases. In this review, we address the most frequently reported parasites that directly infect the myocardium, including Trypanosoma cruzi, the protozoal causative agent of American trypanosomiasis (Chagas disease, and Taenia solium, the cestode causative agent of taeniasis and cysticercosis. We also discuss tropical endomyocardial fibrosis, trichinellosis and schistosomiasis. Health systems, attitudes, the perceptions of both patients and physicians as well as socioeconomic factors should all be explored and recognized as crucial factors for improving the control of cardiovascular diseases in the tropics. Clinicians throughout the world must remain aware of imported parasites as potential causes of cardiac diseases. Keywords: cardiomyopathy, Chagas disease, myocardium, parasitic infection, tropical infections

  4. Selective Retrograde Venous Revascularization of the Myocardium when PCI or CABG Is Impossible: Investigation in a Porcine Model

    DEFF Research Database (Denmark)

    Møller, Christian H; Nørgaard, Martin A; Gøtze, Jens P

    2008-01-01

    We investigated the possibility of nourishing the myocardium through selective retrograde coronary venous bypass grafting (CVBG) with an off-pump technique and evaluated various methods of monitoring the physiological effects of this procedure. In a porcine model, the left internal mammary artery...... tension decreased, but with time some recovery was seen. Cardiac troponin T was elevated. Histological analysis showed ischemic changes. In control pigs, microdialysis was performed for 1.5 hours up to LAD artery ligation, after which all pigs died in ventricular fibrillation arrest. No increase...

  5. New perspectives in the treatment of damaged myocardium using autologous skeletal myoblasts

    International Nuclear Information System (INIS)

    Rigatelli, Gianluca; Rossini, Katia; Vindigni, Vincenzo; Mazzoleni, Francesco; Rigatelli, Giorgio; Carraro, Ugo

    2004-01-01

    Autologous skeletal myoblast transplantation may be used to ameliorate the healing process following myocardium infarct and, hopefully, cardiomyopathies. Despite successful animal experimentation, several issues need to be addressed in clinical settings, i.e., the impact of the delivery route, the extent of short- and long-term survival, and differentiation of the injected skeletal myoblasts. The authors offer some new hypotheses resulting from basic research, i.e., where and when to inject the myogenic cells, whatever their source, how to decrease new myofiber atrophy and improve their regeneration. Although these new hypotheses still need to be tested in humans, they may be decisive for future experimental studies and will lead to making endovascular cell implantation a more effective way to treat ischemic heart disease and failure

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

    Science.gov (United States)

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

    1984-11-01

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

  7. Experimental basis of metabolic imaging of the myocardium with radioiodinated aromatic free fatty acids

    International Nuclear Information System (INIS)

    Reske, S.N.; Knapp, F.F. Jr.; Winkler, C.

    1986-01-01

    For the investigation of myocardial perfusion and left ventricular pump function, advanced radioisotopic techniques have been established. New developments in radiopharmacology and single-photon emission computed tomography have recently enabled the investigation of parameters of regional energy metabolism in well defined areas of the heart muscle. For this purpose, various iodine ( 123 I)-labeled free fatty acids (FFA) have been synthesized. The diagnostic application of labeled FFA in heart disease may be important, since FFA are the preferred substrates for cardiac energy production at rest in the fasting state. In addition, regional myocardial FFA uptake and regional myocardial blood flow are tightly coupled in normal myocardium with beta-oxidation which is extremely sensitive to oxygen deprivation. This article outlines the basic physiologic pathways of FFA in normal and ischemic myocardium and reviews the results of animal experiments validating the application of these principles for metabolic imaging of the heart by means of the aromatic radioiodinated FFA, 15-(p-iodophenyl)pentadecanoic acid. In addition, the development, physiologic properties, and potential applications of a new generation of 3-methyl-substituted radioiodinated fatty acids that show high myocardial uptake but prolonged retention are discussed. 64 references

  8. A Review of Neurogenic Stunned Myocardium

    Science.gov (United States)

    Wongrakpanich, Supakanya; Agrawal, Akanksha; Yadlapati, Sujani; Kishlyansky, Marina; Figueredo, Vincent

    2017-01-01

    Neurologic stunned myocardium (NSM) is a phenomenon where neurologic events give rise to cardiac abnormalities. Neurologic events like stroke and seizures cause sympathetic storm and autonomic dysregulation that result in myocardial injury. The clinical presentation can involve troponin elevation, left ventricular dysfunction, and ECG changes. These findings are similar to Takotsubo cardiomyopathy and acute coronary syndrome. It is difficult to distinguish NSM from acute coronary syndrome based on clinical presentation alone. Because of this difficulty, a patient with NSM who is at high risk for coronary heart disease may undergo cardiac catheterization to rule out coronary artery disease. The objective of this review of literature is to enhance physician's awareness of NSM and its features to help tailor management according to the patient's clinical profile. PMID:28875040

  9. Neurogenic stunned myocardium following hemorrhagic cerebral contusion

    International Nuclear Information System (INIS)

    Deleu, D.; Miyares, F.; Kettern, M.; Kumar, S.; Hassens, Y.; Salim, K.

    2007-01-01

    Neurogenic stunned myocardium NSM is a well-known complication of subarachnoidal hemorrhage, but has been reported rarely in association with other central nervous system disorders. A case of NSM is described in a patient with hemorrhagic brain contusion associated with cerebral edema. An 18-year-old man was admitted with severe cranial trauma following a car roll-over. Six days after admission, he developed findings suggestive for NSM. The troponin T and creatine kinase-MB level were elevated and echocardiogram showed apical and inferoposterior hypokinesis and diffuse left ventricular akinesis with severely reduced ejection fraction 18%. Invasive measurements confirmed low cardiac output. His cardiac function resolved completely within 6 days after decompressive craniotomy. This case supports the presumed unifying role of the increased intracranial pressure, probably triggering a vigorous sympathetic outflow hyperactivity leading to NSM. (author)

  10. Imaging of ischemic heart disease

    International Nuclear Information System (INIS)

    Lipton, Martin J.; Reba, Richard C.; Bogaert, Jan; Boxt, Larry M.

    2002-01-01

    Despite advances in the understanding and treatment of ischemic cardiomyopathy, characterized by extensive coronary artery disease and left ventricular (LV) dysfunction, the prognosis remains poor with only a 50-60% 5-year survival rate. The composition of atherosclerotic lesions is currently regarded as being more important than the degree of stenosis in determining acute events. If imaging techniques could distinguish vulnerable from stable plaques, then high-risk patient subgroups could be identified. Another important concept is that LV dysfunction may be the result of either scarring due to necrosis or to the presence of myocardial hibernation, in which there is sufficient blood flow to sustain viable myocytes, but insufficient to maintain systolic contraction. This concept of myocardial viability is critical for making optimal clinical management decisions. This review describes how noninvasive imaging methods can be used to distinguish regions of irreversibly injured myocardium from viable but hibernating segments. Technical advances in CT and MR have made imaging of the beating heart possible. Considerable clinical progress has already been made and further cardiac applications are expected. Radiologists therefore have new opportunities for involvement in cardiac imaging but must recognize the political implications as well as the diagnostic potential of these modalities not only for the heart, but also for the whole vascular system. This review focuses on imaging myocardial injury. It compares state-of-the-art CT and MR with more established yet contemporary echocardiography and nuclear scintigraphy. (orig.)

  11. The application of remote ischemic conditioning in cardiac surgery [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Zeljko J. Bosnjak

    2017-06-01

    Full Text Available Perioperative myocardial ischemia and infarction are the leading causes of morbidity and mortality following anesthesia and surgery. The discovery of endogenous cardioprotective mechanisms has led to testing of new methods to protect the human heart. These approaches have included ischemic pre-conditioning, per-conditioning, post-conditioning, and remote conditioning of the myocardium. Pre-conditioning and per-conditioning include brief and repetitive periods of sub-lethal ischemia before and during prolonged ischemia, respectively; and post-conditioning is applied at the onset of reperfusion. Remote ischemic conditioning involves transient, repetitive, non-lethal ischemia and reperfusion in one organ or tissue (remote from the heart that renders myocardium more resistant to lethal ischemia/reperfusion injury. In healthy, young hearts, many conditioning maneuvers can significantly increase the resistance of the heart against ischemia/reperfusion injury. The large multicenter clinical trials with ischemic remote conditioning have not been proven successful in cardiac surgery thus far. The lack of clinical success is due to underlying risk factors that interfere with remote ischemic conditioning and the use of cardioprotective agents that have activated the endogenous cardioprotective mechanisms prior to remote ischemic conditioning. Future preclinical research using remote ischemic conditioning will need to be conducted using comorbid models.

  12. Contribution to the study of thallium 201 myocardium scintigraphy

    International Nuclear Information System (INIS)

    Annweiler, Marc.

    1976-01-01

    In this work a new isotope was tested in the field of myocardium scintigraphy: thallium 201. The different radioisotopes used so far in myocardium scintigraphy are reviewed to begin with. The main biological and physical characteristics of thallium and the scintillation camera used for this work are described next. In our opinion thallium 201 owing to its biological behavior similar to that of potassium and to its physical characteristics, appears as one of the better -if not the best- known tracer suitable for use in myocardium scintigraphy. Its properties are suited to the use of a scintillation camera, which considerably shortens the examination time and thus allows an isotopic exploration of the myocardium from several incidences. The only disadvantage of this cyclotron-produced isotope seems to be its high price which will probably limit its use on a large scale. Fifty thallium 201 myocardium scintigraphs were practised on forty-eight coronary thrombosis patients. From this was established a precise topographic correlation between the electrocardiographic diagnosis and the scintigraph. The two corresponded in 47 cases out of 50. The few disagreements between ECG and scintigraphic results seem to be due either to poor-quality images or to an overall myocardium hypofixation connected with a very extensive necrosis. This means that thallium 201 myocardium scintigraphy is a reliable method of examination in the great majority of cases, giving a direct picture of the heart muscle and its necrotic lesions [fr

  13. Ischemic Preconditioning of One Forearm Enhances Static and Dynamic Apnea

    DEFF Research Database (Denmark)

    Kjeld, Thomas; Rasmussen, Mads Reinholdt; Jattu, Timo

    2014-01-01

    INTRODUCTION: Ischemic preconditioning enhances ergometer cycling and swimming performance. We evaluated whether ischemic preconditioning of one forearm (four times for 5 min) also affects static breath hold and underwater swimming, whereas the effect of similar preconditioning on ergometer rowing...... preconditioning reduced the forearm oxygen saturation from 65% ± 7% to 19% ± 7% (mean ± SD; P right thigh.......05). CONCLUSIONS: We conclude that while the effect of ischemic preconditioning (of one forearm) on ergometer rowing was minimal, probably because of reduced muscle oxygenation during the warm-up, ischemic preconditioning does enhance both static and dynamic apnea, supporting that muscle ischemia is an important...

  14. Stem cell therapy for ischemic heart diseases.

    Science.gov (United States)

    Yu, Hong; Lu, Kai; Zhu, Jinyun; Wang, Jian'an

    2017-01-01

    Ischemic heart diseases, especially the myocardial infarction, is a major hazard problem to human health. Despite substantial advances in control of risk factors and therapies with drugs and interventions including bypass surgery and stent placement, the ischemic heart diseases usually result in heart failure (HF), which could aggravate social burden and increase the mortality rate. The current therapeutic methods to treat HF stay at delaying the disease progression without repair and regeneration of the damaged myocardium. While heart transplantation is the only effective therapy for end-stage patients, limited supply of donor heart makes it impossible to meet the substantial demand from patients with HF. Stem cell-based transplantation is one of the most promising treatment for the damaged myocardial tissue. Key recent published literatures and ClinicalTrials.gov. Stem cell-based therapy is a promising strategy for the damaged myocardial tissue. Different kinds of stem cells have their advantages for treatment of Ischemic heart diseases. The efficacy and potency of cell therapies vary significantly from trial to trial; some clinical trials did not show benefit. Diverged effects of cell therapy could be affected by cell types, sources, delivery methods, dose and their mechanisms by which delivered cells exert their effects. Understanding the origin of the regenerated cardiomyocytes, exploring the therapeutic effects of stem cell-derived exosomes and using the cell reprogram technology to improve the efficacy of cell therapy for cardiovascular diseases. Recently, stem cell-derived exosomes emerge as a critical player in paracrine mechanism of stem cell-based therapy. It is promising to exploit exosomes-based cell-free therapy for ischemic heart diseases in the future. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  15. Thallium 201 scintigraphy of the myocardium. A bibliographical survey for image optimisation

    International Nuclear Information System (INIS)

    Chatelier, Luc.

    1979-01-01

    At the request of a Nuclear Medicine Service we compiled a review of the literature on thallium 201 myocardium scintigraphy in order to define the optimum parameters for image acquisition; included also are the bibliograhical references of studies on the sensitivities, specificities and accuracies of this technique as compared with electrocardiography in the diagnosis and evaluation of ischemic heart diseases. This examination seems to have a part to play at all stages in the evaluation of ischemic heart diseases, whether for the detection (ischemia) emergency handling (thrombosis) or post-surgical checking (permeability of an aorto-coronary transplant) of these diseases, the great frequency and gravity of which have no longer to be proved. This study covers the whole period since thallium scintigraphy began (1970) until June 1978. Thallium seems to have a great future in cardiology and may be even in other fields since its use is quoted (in only a few publications as yet) for brain, kidney and pancreas scintigraphy [fr

  16. [Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation].

    Science.gov (United States)

    Khomaziuk, I M; Habulavichene, Zh M; Khomaziuk, V A

    2011-01-01

    Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.

  17. Isoflurane preconditions myocardium against infarction via release of free radicals

    NARCIS (Netherlands)

    Müllenheim, Jost; Ebel, Dirk; Frässdorf, Jan; Preckel, Benedikt; Thämer, Volker; Schlack, Wolfgang

    2002-01-01

    BACKGROUND: Isoflurane exerts cardioprotective effects that mimic the ischemic preconditioning phenomenon. Generation of free radicals is implicated in ischemic preconditioning. The authors investigated whether isoflurane-induced preconditioning may involve release of free radicals. METHODS:

  18. Exponential relationship between DMIPP uptake and blood flow in normal and ischemic canine myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Comans, E.F.I.; Lingen, A. van; Bax, J.J.; Sloof, G.W. [Free Univ. Hospital, Amsterdam (Netherlands). Dept. of Nuclear Medicine; Visser, F.C. [Free Univ. Hospital, Amsterdam (Netherlands). Dept. of Cardiology; Vusse, G.J. van der [Limburg Univ., Maastricht (Netherlands). Cardiovascular Research Inst.; Knapp, F.F. Jun. [Oak Ridge Lab., TN (United States). Nuclear Medicine Group

    1998-12-31

    In 10 open-chest dogs the left anterior descending coronary artery was cannulated and extracorporally bypass (ECB) perfused at reduced flow. Myocardial blood flow (MBF) was assessed with Scandium-46 labeled microspheres. Forty minutes after i.v. injection of DMIPP, the heart was excised and cut into 120 samples. In each sample MBF (ml/g*min) and DMIPP uptake (percentage of the injected dose per gram: %id/g) were assessed. The relation between normalized MBF and DMIPP uptake was assessed using a linear, with a zero and with a non-zero intercept, and an exponential model function: A[1-e{sup -MBF/Fc}], where A and Fc are the amplitude and flow constant, respectively. The goodness of fit for all models was expressed as the standard error of estimate (SEE). In all individual dogs the relation between DMIPP uptake and MBF was significantly better (p<0.001) represented by an exponential model than a linear model with zero intercept. In 8 of 10 dogs the exponential model showed a better fit than the linear model with a non-zero intercept. The difference was significant (p<0.05) in 5 dogs. For Pooled data, linear regression analysis with a non-zero intercept revealed: DMIPP=0.54+0.44*MBF (SEE: 0.18) and with a zero intercept: DMIPP=0.97*MBF (SEE: 0.27). The goodness of fit of the exponential model: DMIPP=1.07[1-e{sup -MBF/0.35}] (SEE: 0.15) was significantly better (p<0.0001) than the linear models. In the normal to low MBF range, uptake of the dimenthyl branched fatty acid analogue DMIPP shows an exponential relationship, which is more appropriate than a linear relationship from a physiological point of view. (orig./MG) [Deutsch] An 10 Hunden mit eroeffnetem Brustkorb wurde der Ramus interventricularis anterior der linken Koronararterie kanueliert und ueber einen extrakorporalen Bypass (ECB) mit einem reduzierten Fluss perfundiert. Der myokardiale Blutfluss (MBF) wurde ueber Scandium-46-markierte Mikrosphaeren erfasst. Vierzig Minuten nach der iv. Injektion von DMIPP wurde das Herz exzidiert und in 120 Stuecke geschnitten. In jedem Stueck wurde der MBF (ml/g*min) und die DMIPP-Aufnahme (Prozent der injizierten Dosis pro Gramm Gewebe: %id/g) gemessen. Der Zusammenhang zwischen dem normalisierten MBF und dem DMIPP-Uptake wurde einmal ueber eine lineare Modellfunktion (mit und ohne Nulldurchgang) und zweitens ueber eine exponentielle Funktion gefittet: A[1-e{sup -MBF/Fc}], wobei A die Amplitude und Fc eine Flusskonstante darstellen. Die Guete der Anpassung fuer alle Modelle wurde ueber den Standardfehler der Schaetzung (SEE) berechnet. Intraindividuell wurde der Zusammenhang zwischen der DMIPP-Aufnahme und dem MBF bei allen Hunden signifikant (p<0,001) durch den exponentiellen Fit repraesentiert, verglichen mit dem linearen Modell mit Nulldurchgang. Bei acht von zehn Hunden zeigte das exponentielle Modell einen besseren Fit als das Lineare ohne Nulldurchgang. Der Unterschied war bei fuenf Hunden signifikant (p<0,05). Die lineare Regression fuer die zusammengefassten Daten ohne Nulldurchgang ergab: DMIPP=0,54+0,44*MBF (SEE: 0,18), mit einem Nulldurchgang: DMIPP=0.97*MBF (SEE: 0,27). Die Guete des Fits des exponentiellen Modells war mit DMIPP=1,07*[1-e{sup -MBF/0,35}] (SEE: 0,15) signifkant besser (p<0,0001), verglichen mit dem linearen. Im Bereich normaler bis niedriger MBF-Werte zeigt die Aufnahme des Fettsaeureanalogons DMIPP eine exponentielle Relation, die aus physiologischer Sicht besser geeignet ist als eine lineare Relation. (orig./MG)

  19. Fatty acid uptake in normal human myocardium

    International Nuclear Information System (INIS)

    Vyska, K.; Meyer, W.; Stremmel, W.; Notohamiprodjo, G.; Minami, K.; Machulla, H.J.; Gleichmann, U.; Meyer, H.; Koerfer, R.

    1991-01-01

    Fatty acid binding protein has been found in rat aortic endothelial cell membrane. It has been identified to be a 40-kDa protein that corresponds to a 40-kDa fatty acid binding protein with high affinity for a variety of long chain fatty acids isolated from rat heart myocytes. It is proposed that this endothelial membrane fatty acid binding protein might mediate the myocardial uptake of fatty acids. For evaluation of this hypothesis in vivo, influx kinetics of tracer-labeled fatty acids was examined in 15 normal subjects by scintigraphic techniques. Variation of the plasma fatty acid concentration and plasma perfusion rate has been achieved by modulation of nutrition state and exercise conditions. The clinical results suggest that the myocardial fatty acid influx rate is saturable by increasing fatty acid plasma concentration as well as by increasing plasma flow. For analysis of these data, functional relations describing fatty acid transport from plasma into myocardial tissue in the presence and absence of an unstirred layer were developed. The fitting of these relations to experimental data indicate that the free fatty acid influx into myocardial tissue reveals the criteria of a reaction on a capillary surface in the vicinity of flowing plasma but not of a reaction in extravascular space or in an unstirred layer and that the fatty acid influx into normal myocardium is a saturable process that is characterized by the quantity corresponding to the Michaelis-Menten constant, Km, and the maximal velocity, Vmax, 0.24 ± 0.024 mumol/g and 0.37 ± 0.013 mumol/g(g.min), respectively. These data are compatible with a nondiffusional uptake process mediated by the initial interaction of fatty acids with the 40-kDa membrane fatty acid binding protein of cardiac endothelial cells

  20. Beneficial effect of medicinal plants on the contractility of post-hypoxic isolated guinea pig atria - Potential implications for the treatment of ischemic-reperfusion injury

    NARCIS (Netherlands)

    Bipat, Robbert; Toelsie, Jerry R.; Magali, Indira; Soekhoe, Rubaina; Stender, Karin; Wangsawirana, Angelique; Oedairadjsingh, Krishan; Pawirodihardjo, Jennifer; Mans, Dennis R. A.

    Context Ischemic-reperfusion injury is accompanied by a decreased contractility of the myocardium. Positive-inotropic agents have proven useful for treating this condition but may exert serious side-effects.Objective In this study, aqueous preparations from Abelmoschus esculentus L. Moench

  1. Construction of PR39 recombinant AAV under control of the HRE promoter and the effect of recombinant AAV on gene therapy of ischemic heart disease.

    Science.gov (United States)

    Sun, Lijun; Hao, Yuewen; Nie, Xiaowei; Zhang, Xuexin; Yang, Guangxiao; Wang, Quanying

    2012-11-01

    The objective of this study was to investigate the effect of the PR39 recombinant adeno-associated virus (AAV) controlled by the hypoxia-responsive element (HRE) on gene therapy of ischemic heart disease. The minimal HRE was artificially synthesized and the AAV vector controlled by HRE was introduced with NT4-TAT-His-PR39 to investigate the expression of AAV-PR39 in hypoxic vascular endothelial cells (VEC) of human umbilical vein (CRL-1730 cell line) and the angiogenesis-promoting effect in pigs with acute myocardial infraction (AMI). The minimal HRE/CMV was designed and artificially synthesized using the PCR method and cloned with the T vector cloning method. The pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV plasmid was constructed. Using the calcium phosphate precipitation method, HEK-293 cells were co-transfected with three plasmids to produce the recombinant virus. An equal volume of pSS-HRE-CMV-NT4-6His-PR39-PolyAAAV and enterovirus (EV, blank virus) was transfected into CRL-1730 cell lines, respectively. The immunohistochemical method was used to assay the expression of 6xHis in CRL-1730 cell lines and the expression of PR39 under hypoxia. Eighteen AMI miniature pigs were randomized into the experimental group (HRE-AAV-PR39 group), control group 1 (physical saline group) and control group 2 (EV group). The area of ischemia was assessed with conventional MRI and myocardium perfusion MRI. Pigs were sacrificed at preset time-points to obtain samples of ischemic myocardium. Morphological and pathological data were collected. According to data in the literature and databases, the minimal HRE was designed and synthesized with the PCR method. A large number of HREs were connected to modified pSSHGAAV (pSSV9int-/XbaI) vector followed by insertion of the NT4-6His-PR39 gene segment and, thus, the recombinant plasmid pSS-HRE-CMV-NT4-6His-PR39-PolyA-AAV was successfully constructed. The expression of 6xHis in CRL-1730 cells under the regulation of HRE was assayed using the

  2. Enhanced Electrical Integration of Engineered Human Myocardium via Intramyocardial versus Epicardial Delivery in Infarcted Rat Hearts.

    Directory of Open Access Journals (Sweden)

    Kaytlyn A Gerbin

    Full Text Available Cardiac tissue engineering is a promising approach to provide large-scale tissues for transplantation to regenerate the heart after ischemic injury, however, integration with the host myocardium will be required to achieve electromechanical benefits. To test the ability of engineered heart tissues to electrically integrate with the host, 10 million human embryonic stem cell (hESC-derived cardiomyocytes were used to form either scaffold-free tissue patches implanted on the epicardium or micro-tissue particles (~1000 cells/particle delivered by intramyocardial injection into the left ventricular wall of the ischemia/reperfusion injured athymic rat heart. Results were compared to intramyocardial injection of 10 million dispersed hESC-cardiomyocytes. Graft size was not significantly different between treatment groups and correlated inversely with infarct size. After implantation on the epicardial surface, hESC-cardiac tissue patches were electromechanically active, but they beat slowly and were not electrically coupled to the host at 4 weeks based on ex vivo fluorescent imaging of their graft-autonomous GCaMP3 calcium reporter. Histologically, scar tissue physically separated the patch graft and host myocardium. In contrast, following intramyocardial injection of micro-tissue particles and suspended cardiomyocytes, 100% of the grafts detected by fluorescent GCaMP3 imaging were electrically coupled to the host heart at spontaneous rate and could follow host pacing up to a maximum of 300-390 beats per minute (5-6.5 Hz. Gap junctions between intramyocardial graft and host tissue were identified histologically. The extensive coupling and rapid response rate of the human myocardial grafts after intramyocardial delivery suggest electrophysiological adaptation of hESC-derived cardiomyocytes to the rat heart's pacemaking activity. These data support the use of the rat model for studying electromechanical integration of human cardiomyocytes, and they

  3. Myocardium repair with stem cell therapy

    International Nuclear Information System (INIS)

    Peix, Amalia; Hidalgo, Jose; Dorticos, Elvira; Llerena, Lorenzo; Paredes, Angel; Torres, Maritza; Macias, Consuelo; Del Valle, Lazaro; Cabrera, Lazaro O; Carrillo, Regla; Mena, Eric; Fernandez, Yoel

    2006-01-01

    With the aim of assessing the efficacy of bone marrow-derived stem cells transplantation in patients with myocardial infarction and severe chronic heart failure through nuclear cardiology techniques, 15 revascularized patients were studied: nine (Group I) received autologous bone marrow-derived stem cells. The other six were controls (Group II). All underwent a clinical evaluation, radionuclide ventriculography, and gated-SPECT myocardial perfusion scintigraphy (MIBI-technetium99m, two-day protocol: dipyridamole - rest), before and three months after the procedure. At three months there was a clinical improvement in 89% of patients from Group I. The left ventricular ejection fraction increased: from 32±9% to 44±13% (p=0.03; Group I) and from 38±2% to 48±14% (p NS; Group II). The peak filling rate improved from 120±11 to 196±45 EDV/sec (p=0.03; Group I). The dipyridamole summed score diminished significantly only in Group I (from 35±5 to 23±14; p=0.02). The perfusion improvement was related to the implantation site in 60% of cases. We conclude that the bone marrow-derived stem cells transplantation is effective in patients with severe chronic heart failure of ischemic origin (au)

  4. Semi-automatic segmentation of myocardium at risk in T2-weighted cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Sjögren Jane

    2012-01-01

    Full Text Available Abstract Background T2-weighted cardiovascular magnetic resonance (CMR has been shown to be a promising technique for determination of ischemic myocardium, referred to as myocardium at risk (MaR, after an acute coronary event. Quantification of MaR in T2-weighted CMR has been proposed to be performed by manual delineation or the threshold methods of two standard deviations from remote (2SD, full width half maximum intensity (FWHM or Otsu. However, manual delineation is subjective and threshold methods have inherent limitations related to threshold definition and lack of a priori information about cardiac anatomy and physiology. Therefore, the aim of this study was to develop an automatic segmentation algorithm for quantification of MaR using anatomical a priori information. Methods Forty-seven patients with first-time acute ST-elevation myocardial infarction underwent T2-weighted CMR within 1 week after admission. Endocardial and epicardial borders of the left ventricle, as well as the hyper enhanced MaR regions were manually delineated by experienced observers and used as reference method. A new automatic segmentation algorithm, called Segment MaR, defines the MaR region as the continuous region most probable of being MaR, by estimating the intensities of normal myocardium and MaR with an expectation maximization algorithm and restricting the MaR region by an a priori model of the maximal extent for the user defined culprit artery. The segmentation by Segment MaR was compared against inter observer variability of manual delineation and the threshold methods of 2SD, FWHM and Otsu. Results MaR was 32.9 ± 10.9% of left ventricular mass (LVM when assessed by the reference observer and 31.0 ± 8.8% of LVM assessed by Segment MaR. The bias and correlation was, -1.9 ± 6.4% of LVM, R = 0.81 (p Conclusions There is a good agreement between automatic Segment MaR and manually assessed MaR in T2-weighted CMR. Thus, the proposed algorithm seems to be a

  5. Semi-automatic segmentation of myocardium at risk in T2-weighted cardiovascular magnetic resonance.

    Science.gov (United States)

    Sjögren, Jane; Ubachs, Joey F A; Engblom, Henrik; Carlsson, Marcus; Arheden, Håkan; Heiberg, Einar

    2012-01-31

    T2-weighted cardiovascular magnetic resonance (CMR) has been shown to be a promising technique for determination of ischemic myocardium, referred to as myocardium at risk (MaR), after an acute coronary event. Quantification of MaR in T2-weighted CMR has been proposed to be performed by manual delineation or the threshold methods of two standard deviations from remote (2SD), full width half maximum intensity (FWHM) or Otsu. However, manual delineation is subjective and threshold methods have inherent limitations related to threshold definition and lack of a priori information about cardiac anatomy and physiology. Therefore, the aim of this study was to develop an automatic segmentation algorithm for quantification of MaR using anatomical a priori information. Forty-seven patients with first-time acute ST-elevation myocardial infarction underwent T2-weighted CMR within 1 week after admission. Endocardial and epicardial borders of the left ventricle, as well as the hyper enhanced MaR regions were manually delineated by experienced observers and used as reference method. A new automatic segmentation algorithm, called Segment MaR, defines the MaR region as the continuous region most probable of being MaR, by estimating the intensities of normal myocardium and MaR with an expectation maximization algorithm and restricting the MaR region by an a priori model of the maximal extent for the user defined culprit artery. The segmentation by Segment MaR was compared against inter observer variability of manual delineation and the threshold methods of 2SD, FWHM and Otsu. MaR was 32.9 ± 10.9% of left ventricular mass (LVM) when assessed by the reference observer and 31.0 ± 8.8% of LVM assessed by Segment MaR. The bias and correlation was, -1.9 ± 6.4% of LVM, R = 0.81 (p Segment MaR, -2.3 ± 4.9%, R = 0.91 (p Segment MaR and manually assessed MaR in T2-weighted CMR. Thus, the proposed algorithm seems to be a promising, objective method for standardized MaR quantification in T2

  6. High expression of arachidonate 15-lipoxygenase and proinflammatory markers in human ischemic heart tissue

    International Nuclear Information System (INIS)

    Magnusson, Lisa U.; Lundqvist, Annika; Asp, Julia; Synnergren, Jane; Johansson, Cecilia Thalén; Palmqvist, Lars; Jeppsson, Anders; Hultén, Lillemor Mattsson

    2012-01-01

    Highlights: ► We found a 17-fold upregulation of ALOX15 in the ischemic heart. ► Incubation of human muscle cells in hypoxia showed a 22-fold upregulation of ALOX15. ► We observed increased levels of proinflammatory markers in ischemic heart tissue. ► Suggesting a link between ischemia and inflammation in ischemic heart biopsies. -- Abstract: A common feature of the ischemic heart and atherosclerotic plaques is the presence of hypoxia (insufficient levels of oxygen in the tissue). Hypoxia has pronounced effects on almost every aspect of cell physiology, and the nuclear transcription factor hypoxia inducible factor-1α (HIF-1α) regulates adaptive responses to low concentrations of oxygen in mammalian cells. In our recent work, we observed that hypoxia increases the proinflammatory enzyme arachidonate 15-lipoxygenase (ALOX15B) in human carotid plaques. ALOX15 has recently been shown to be present in the human myocardium, but the effect of ischemia on its expression has not been investigated. Here we test the hypothesis that ischemia of the heart leads to increased expression of ALOX15, and found an almost 2-fold increase in HIF-1α mRNA expression and a 17-fold upregulation of ALOX15 mRNA expression in the ischemic heart biopsies from patients undergoing coronary bypass surgery compared with non ischemic heart tissue. To investigate the effect of low oxygen concentration on ALOX15 we incubated human vascular muscle cells in hypoxia and showed that expression of ALOX15 increased 22-fold compared with cells incubated in normoxic conditions. We also observed increased mRNA levels of proinflammatory markers in ischemic heart tissue compared with non-ischemic controls. In summary, we demonstrate increased ALOX15 in human ischemic heart biopsies. Furthermore we demonstrate that hypoxia increases ALOX15 in human muscle cells. Our results yield important insights into the underlying association between hypoxia and inflammation in the human ischemic heart disease.

  7. Arachidonic acid metabolism in fibroblasts derived from canine myocardium

    International Nuclear Information System (INIS)

    Weber, D.R.; Prescott, S.M.

    1986-01-01

    Canine fibroblasts from normal or healing infarcted myocardium were grown in culture. The cells were morphologically indistinguishable, but the doubling time of cells from healing myocardium was 39.6 +/- 3.5 hr whereas that of normals was 24 +/- 3.7 (n=5, p 3 H]arachidonate (AA) into phospholipids. Calcium ionophore A23187 (10 μM) caused release and metabolism of [ 3 H] AA. A23187 or AA (10μM) induced production of 6-keto PGF1α, PGE2, and a hydroxy metabolite of AA. RIA of 6-keto PGF1α showed that subconfluent cells from healing myocardium produced 1202 +/- 354 pg/mg protein whereas that of normals was 551 +/- 222 (n=7, p 3 H]AA released but did not metabolize [ 3 H]AA. In coincubations, fibroblasts incorporated myocyte-derived AA. Subsequent stimulation of the fibroblasts with A23187 induced the synthesis of 6-keto PGF1α, PGE2 and a hydroxy metabolite. The fibroblast content of healing myocardium was 35-1000 times that of normal tissue (n=7). Thus even a moderate change in AA metabolism, amplified by the AA released from deteriorating myocytes, may be a significant physiologic or pathologic event

  8. Minimal surfaces

    CERN Document Server

    Dierkes, Ulrich; Sauvigny, Friedrich; Jakob, Ruben; Kuster, Albrecht

    2010-01-01

    Minimal Surfaces is the first volume of a three volume treatise on minimal surfaces (Grundlehren Nr. 339-341). Each volume can be read and studied independently of the others. The central theme is boundary value problems for minimal surfaces. The treatise is a substantially revised and extended version of the monograph Minimal Surfaces I, II (Grundlehren Nr. 295 & 296). The first volume begins with an exposition of basic ideas of the theory of surfaces in three-dimensional Euclidean space, followed by an introduction of minimal surfaces as stationary points of area, or equivalently

  9. [Effect of adaptation to hypoxia on expression of NO synthase isoforms in rat myocardium].

    Science.gov (United States)

    Goryacheva, A V; Terekhina, O L; Abramochkin, D V; Budanova, O P; Belkina, L M; Smirin, B V; Downey, H F; Malyshev, I Yu; Manukhina, E B

    2015-01-01

    Previously we have shown that adaptation to hypoxia (AH) is cardio- and vasoprotective in myocardial ischemic and reperfusion injury and this protection is associated with restriction of nitrosative stress. The present study was focused on further elucidation of NO-dependent mechanisms of AH by identifying specific NO synthases (NOS) that could play the major role in AH protection. AH was performed in a normobaric hypoxic chamber by breathing hypoxic gas mixture (9.5-10% O2) for 5-10 min with intervening 4 min normoxia (5-8 cycles daily for 21 days). Expression of neuronal (nNOS), inducible (iNOS), and endothelial (eNOS) protein was measured in the left ventricular myocardium using Western blot analysis with respective antibodies. AH educed iNOS protein expression by 71% (p < 0.05) whereas eNOS protein expression tended to be reduced by 41% compared to control (p < 0.05). nNOS protein expression remained unchanged after AH. Selective iNOS inhibition can mimic the AH-induced protection. Therefore protective effects of AH could be at least partially due to restriction of iNOS and, probably, eNOS expression.

  10. Canine study on myocardial ischemic memory with 18F-FDG PET/CT imaging

    International Nuclear Information System (INIS)

    Xie Boqia; Yang Minfu; Dou Kefei; Han Chunlei; Tian Yi; Zhang Ping; Yang Zihe; Yin Jiye; Wang Hao

    2012-01-01

    Objective: To explore whether the existence and duration of ischemia measured by dynamic 18 F-FDG PET/CT imaging correlated with the extent of myocardial ischemia in a canine model of myocardial ischemia-reperfusion. Methods: Canine coronary artery occlusion was carried out for 20 min (n=4) and for 40 min (n=4) followed by 24 h of open-artery reperfusion. All dogs underwent dynamic 18 F-FDG PET/CT and 99 Tc m -MIBI SPECT imaging at baseline and 1 h and 24 h after reperfusion.Quantitative analysis of myocardial 18 F-FDG uptake was performed using Carimas Core software,and the extraction ratio of 18 F-FDG (K) was calculated by the ratio of 18 F-FDG uptake rate in the ischemic area (k ischemia ) and normoperfused region (k normoperfused ). Echocardiographic data were also acquired between each PET/CT imaging study to detect the wall motion in the ischemic and normoperfused myocardium. Paired t test and non-parametric statistical tests, measured by SPSS 19.0, were used to analyze the data. Results: Coronary occlusion produced sustained, abnormal wall motion in the ischemic region for more than 1 h. Similar K values were demonstrated between the 20 min and 40 min groups at baseline (1.02 ±0.06 and 1.03 ±0.05, Z=-0.29, P>0.05). At 1 h after reperfusion, the reperfusion regions showed normal perfusion but with increased 18 F-FDG uptake, which was higher in the 40 min ischemic group than in the 20 min ischemic group (2.31 ±0.13 and 1.87 ±0.09, Z=-2.31, P<0.05). At 24 h after reperfusion, however, only the 40 min ischemic group showed slightly higher 18 F-FDG uptake than baseline (1.15 ± 0.02 and 1.03 ±0.05, t=4.32, P<0.05), whereas no significant difference was found in the 20 min ischemic group (1.05 ± 0.04 and 1.02 ± 0.06, t=0.87, P>0.05). Histological examination of the ischemic myocardium from both groups revealed neatly arranged cells without interstitial edema, hemorrhage nor inflammatory response. Conclusions: Myocardial 'ischemic memory' was

  11. Ischemic necrosis and osteochondritis

    International Nuclear Information System (INIS)

    Weissman, S.D.

    1989-01-01

    Osteonecrosis indicates that ischemic death of the cellular constituents of bone and marrow has occurred. Historically, this first was thought to be related to sepsis in the osseous segments. However, continued studies led to the use of the term aseptic necrosis. Subsequent observations indicated that the necrotic areas of bone were not only aseptic, but were also avascular. This led to the terms ischemic necrosis, vascular necrosis and bone infarction. Ischemic necrosis of bone is discussed in this chapter. It results from a significant reduction in or obliteration of blood supply to the affected area. The various bone cells, including osteocytes, osteoclasts, and osteoblasts, usually undergo anoxic death in 12 to 48 hours after blood supply is cut off. The infarct that has thus developed in three-dimensional and can be divided into a number of zones: a central zone of cell death; an area of ischemic injury, most severe near the zone of cell death, and lessening as it moves peripherally; an area of active hyperemia and the zone of normal unaffected tissue. Once ischemic necrosis has begun, the cellular damage provokes an initial inflammatory response, which typically is characterized by vasodilatation, transudation of fluid and fibrin, and local infiltration of flammatory cells. This response can be considered the first stage in repair of the necrotic area

  12. Incidence of stunned, hibernating and scarred myocardium in ischaemic cardiomyopathy

    International Nuclear Information System (INIS)

    Hernandez-Pampaloni, Miguel; Morita, Koichi; Dutka, David P.; Camici, Paolo G.; Bax, Jeroen J.

    2005-01-01

    Different criteria to identify residual viability in chronically dysfunctioning myocardium in patients with coronary artery disease (CAD) can be derived by the combined assessment of myocardial blood flow (MBF) and glucose utilisation (MRG) using positron emission tomography (PET). The aim of this study was to evaluate, in a large number of patients, the prevalence of these different patterns by purely quantitative means. One hundred and sixteen consecutive patients with ischaemic cardiomyopathy (LVEF ≤40%) underwent resting 2D echocardiography to assess regional contractile function (16-segment model). PET with 15 O-labelled water (H 2 15 O) and 18 F-fluorodeoxyglucose (FDG) was used to quantify MBF and MRG during hyperinsulinaemic euglycaemic clamp. Dysfunctional segments with normal MBF (≥0.6 ml min -1 g -1 ) were classified as stunned, and segments with reduced MBF ( -1 g -1 ) as hibernating if MRG was ≥0.25 μmol min -1 g -1 . Segments with reduced MBF and MRG -1 g -1 were classified as transmural scars and segments with reduced MBF and MRG between 0.20 and 0.25 μmol min -1 g -1 as non-transmural scars. Eight hundred and thirty-four (46%) segments were dysfunctional. Of these, 601 (72%) were chronically stunned, with 368 (61%) having normal MRG (0.47±0.20 μmol min -1 g -1 ) and 233 (39%) reduced MRG (0.16±0.05 μmol min -1 g -1 ). Seventy-four (9%) segments with reduced MBF had preserved MRG (0.40±0.18 μmol min -1 g -1 ) and were classified as hibernating myocardium. In addition, 15% of segments were classified as transmural and 4% as non-transmural scar. The mean MBF was highest in stunned myocardium (0.95±0.32 ml min -1 g -1 ), intermediate in hibernating myocardium and non-transmural scars (0.47±0.09 ml min -1 g -1 and 0.48±0.08 ml min -1 g -1 , respectively), and lowest in transmural scars (0.40±0.14 ml min -1 g -1 , P -1 g -1 vs 0.46±0.20 μmol min -1 g -1 , NS), and lowest in stunned myocardium with reduced MRG and transmural scars

  13. Clinical evaluation of ischemic heart diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Fumio [Sendai Railway Hospital (Japan)

    1983-09-01

    Attempt were made to detect the existence of myocardial ischemia by means of both radiographic and scintigraphic techniques. Firstly, a new polygraph was especially designed for selecting the arbitrary phases in a cardiac cycle at which the corresponding radiogram should be synchronously obtained. A comparative investigation on the difference between end-systolic and-diastolic cardiac transverse diameters revealed a remarkable difference of 3.6% in normal subjects and 0.6% in patients with ischemic heart disease. These data indicating the difference of overall heart size was reflected in local dyskinesis documentation of recently developed techniques. For daily clinical purposes, radiography of the chest based on synchronously selected phases would contribute to accurate diagnosis and treatment of heart disease. Secondly, scintigraphic display using intravenously injected thallium-201 was clinically applied. For detection of ischemia, comparative study was performed of initial image relative to selective coronary cineangiography and stress scintigraphy. The former indicated a good correlation of 90%, whereas the latter served to enhance sensitivity. Sequential images (initial and delayed) facilitated the distinction of normal, necrotic, and ischemic areas. Scintigram was used for objective evaluation of coronary dilator (dilazep), either at immediate or follow-up stage. In the same way, it was also possible to indicate the effectiveness of sublingually given nitroglycerin by myocardial scintigram, where by significant increase of uptake was observed 20 minutes after administration. Rehabilitation after acute heart disease was discussed, especially on the peripheral effect. Ratio of the thigh muscle to myocardium shown in this study was useful for objective evaluation. Another preliminary study is to separate normal coronary arteries from myocardial necrosis.

  14. Clinical evaluation of ischemic heart diagnosis

    International Nuclear Information System (INIS)

    Kamei, Fumio

    1983-01-01

    Attempt were made to detect the existence of myocardial ischemia by means of both radiographic and scintigraphic techniques. Firstly, a new polygraph was especially designed for selecting the arbitrary phases in a cardiac cycle at which the corresponding radiogram should be synchronously obtained. A comparative investigation on the difference between end-systolic and-diastolic cardiac transverse diameters revealed a remarkable difference of 3.6% in normal subjects and 0.6% in patients with ischemic heart disease. These data indicating the difference of overall heart size was reflected in local dyskinesis documentation of recently developed techniques. For daily clinical purposes, radiography of the chest based on synchronously selected phases would contribute to accurate diagnosis and treatment of heart disease. Secondly, scintigraphic display using intravenously injected thallium-201 was clinically applied. For detection of ischemia, comparative study was performed of initial image relative to selective coronary cineangiography and stress scintigraphy. The former indicated a good correlation of 90%, whereas the latter served to enhnace sensitivity. Sequential images (initial and delayed) facilitated the distinction of normal, necrotic, and ischemic areas. Scintigram was used for objective evaluation of coronary dilator (dilazep), either at immediate or follow-up stage. In the same way, it was also possible to indicate the effectiveness of sublingually given nitroglycerin by myocardial scintigram, where by significant increase of uptake was observed 20 minutes after administration. Rehabilitation after acute heart disease was discussed, especially on the peripheral effect. Ratio of the thigh muscle to myocardium shown in this study was useful fer objective evaluation. Another preliminary study is to separate normal coronary arteries from myocardial necrosis. (J.P.N.)

  15. 99m Technetium pyrophosphate myocardium scintigraphy. First results

    International Nuclear Information System (INIS)

    Toussaint, Paul.

    1976-01-01

    99m technetium pyrophosphate myocardium scintigraphy is a very recent examination technique. This work gives the results obtained on 61 patients. As a vector of the isotope, pyrophosphate has the advantage over polyphosphate of a fast bone uptake there it should be stressed that a 90 minute pause is necessary between the intraveinous injection of the isotope and the photographic recording so that the reading is not troubled by the labelled intracardiac blood pool image, an image quality criterion being the estimation of a good costal fixation which in fact appears sooner or later according to the subject. The role of pyrophosphate, chelator of calcium in fixation of the isotope on the myocardium, could be explained by the fast appearance of 'dense bodies', made up of calcium hydroxyapathice crystals, in the mitochondria of myocardium cells having undergone an irreversible necrotic process. The choice of 99 m technetium is based on its ease of use: 6 hour half-life, high-energy pure gamma emission at 140 keV. The fixed image studied under two incidences, front and left anterior oblique, is obtained from mobile images given by the scintillation camera used in connection with a data processing system. Several facts are underlined, explaining the disadvantages, advantages and indications of the method [fr

  16. Ischemic strokes and migraine

    Energy Technology Data Exchange (ETDEWEB)

    Bousser, M.G.; Baron, J.C.; Chiras, J.

    1985-11-01

    Lasting neurological deficits, though most infrequent, do occur in migrainous subjects and are well documented by clinical angiographic computed tomographic (CT scan) and even pathological studies. However the mechanism of cerebral ischemia in migraine remains widely unknown and the precise role of migraine in the pathogenesis of ischemic strokes is still debated. (orig./MG).

  17. BIOPREPARATIONS USING IN THE ISCHEMIC HEART INJURY THERAPY

    Directory of Open Access Journals (Sweden)

    A. K. Gulevsky

    2013-04-01

    Full Text Available Possibility of biologically active substances using such as growth factors, cytomedines, natural antioxidants, substances contained in extracts from juvenile and fetal organs and animal tissues in the experiments and clinic of ischemic heart injury are discussed. Along with the well-studied and widely used in clinical practice biopreparations such as kordialin, actovegin, erbisol nesiritide, energostim, as promising tools for treatment of cardiovascular diseases, the extracts from the heart and low molecular weight fraction of cord blood are considered. It is shown that using of tissue reparative embriofetoplatsenta complex increases myocardial contractility. The main difference between these biopreparations and biogenic stimulants is that they have a balanced composition of biologically active substances, in particular different activators of regeneration and differentiation (fibroblast growth factors, nerve-stimulating factor and macrophage erythroid colonies and anti-proliferative cytokines preventing cellular and systemic hyperstimulation as well as other substances able to initiate a directed differentiation of stem cells and to affect regeneration of human myocardium, and hence to optimize the treatment of myocardial infarction. In addition, fetal cells and their associates are almost nonimmunogens. Thus, if the growth factors and differentiation capable to regulate the mitotic activity of cardiomyocytes are determined, it will be possible to initiate a process of stem cells directed differentiation and affect on the human myocardium regeneration, and hence to optimize the treatment of myocardial infarction.

  18. The possibilities of using scale-selective polarization cartography in diagnostics of myocardium pathologies

    Science.gov (United States)

    Ushenko, Yu. A.; Wanchuliak, O. Y.

    2013-06-01

    The optical model of polycrystalline networks of myocardium protein fibrils is presented. The technique of determining the coordinate distribution of polarization azimuth of the points of laser images of myocardium histological sections is suggested. The results of investigating the interrelation between the values of statistical (statistical moments of the 1st-4th order) parameters are presented which characterize distributions of wavelet-coefficients polarization maps of myocardium layers and death reasons.

  19. Mismatched regional myocardial uptake between [sup 123]I-BMIPP and [sup 201]Tl SPECT; Comparison between hypertrophic myocardium and dilated myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, Makoto; Ichiya, Yuichi; Kuwabara, Yasuo; Sasaki, Masayuki; Fukumura, Toshimitsu; Masuda, Kouji; Ejima, Junichi; Tsuda, Yasuo (Kyushu Univ., Fukuoka (Japan). Faculty of Medicine)

    1992-07-01

    The distribution of a new myocardial fatty acid metabolic agent [sup 123]I-BMIPP was compared in 6 each patients with hypertrophic myocardium (4 cases of hypertensive heart disease and 2 of hypertrophic cardiomyopathy) and dilated myocardium (4 of dilated type of valvular heart disease and 2 of dilated cardiomyopathy) with that of [sup 201]Tl. Mismatched regional myocardial uptake between [sup 123]I-BMIPP and [sup 201]Tl SPECT was observed in all of the hypertrophic myocardium, however no but one in the dilated myocardium. Relative increase or decrease in regional BMIPP from the images of 20 min and to those of 4 h was observed in 3 cases of the hypertrophic myocardium. FDG-PET was performed in 2 cases of the hypertrophic myocardium. The distribution of FDG was different from neither those of BMIPP nor Tl in a hypertrophic cardiomyopathy case with the reserved distribution of BMIPP and Tl. Although more investigations are necessary, we concluded that [sup 123]I-BMIPP is a promising radiopharmaceutical for evaluating myocardial fatty acid metabolism in hypertrophic myocardium. (author).

  20. The comparison of nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201Tl re-injection imaging to detect viable myocardium

    International Nuclear Information System (INIS)

    Gao Zhou; Shi yu; Chen Hongyan; Jia Shaowei

    2002-01-01

    Objective: Employing the differences in physical properties of 99m Tc-MIBI and 201 Tl, the authors discuss the contrast result of nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging to detect viable myocardium so that authors can enhance the image quality and shorten the examination time. Method: 34 OMI patients took the 99m Tc-MIBI and 201 Tl dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging respectively in two weeks. During the peak of normal dipyridamole stress i.v. 201 Tl 100 MBq was given and myocardium imaging was taken 15 min later. The dual-isotope group was given nitroglycerin 1mg under the tongue. Five min later, i.v. 99m Tc-MIBI 1110 mBq was given. In 201 Tl re-injection group i.v. 201 Tl 40 MBq was given 4 hour later and were imaged. Among the 34 OMI patients, 19 patients undertook another 99m Tc-MIBI static imaging. Results: There are no obvious differences between nitroglycerin interventional dual-isotope myocardium perfusion imaging and 201 Tl re-injection imaging in detection rate of viable myocardium, χ 2 =0.823, p>0.25. But they have great difference in perfusion changed sectional myocardium absorb rate, t=2.73, p 2 =27.867, p 201 Tl re-injection imaging

  1. Recommendations to realise and interpret the scintigraphy of myocardium perfusion

    International Nuclear Information System (INIS)

    Manrique, A.; Marie, P.Y.

    2003-06-01

    The purpose of these recommendations is to help the physicians in the realization and the interpretation of the tomo-scintigraphies of myocardium perfusion, when this examination is made at the patients having a known or suspected coronary incapacity. These recommendations aim to encourage the practitioners (of nuclear medicine) to reflect and to discuss the procedures applied in their services. These procedures must be also adapted, in every service, to the peculiarities of the environment and to the experiment of each one. (N.C.)

  2. [Genetics of ischemic stroke].

    Science.gov (United States)

    Gschwendtner, A; Dichgans, M

    2013-02-01

    Stroke is one of the most widespread causes of mortality und disability worldwide. Around 80 % of strokes are ischemic and different forms of intracranial bleeding account for the remaining cases. Monogenic stroke disorders are rare but the diagnosis may lead to specific therapeutic consequences for the affected patients who are predominantly young. In common sporadic stroke, genetic factors play a role in the form of susceptibility genes. Their discovery may give rise to new therapeutic options in the future.

  3. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury.

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury.

  4. Repetitive stimulation of autophagy-lysosome machinery by intermittent fasting preconditions the myocardium to ischemia-reperfusion injury

    Science.gov (United States)

    Godar, Rebecca J; Ma, Xiucui; Liu, Haiyan; Murphy, John T; Weinheimer, Carla J; Kovacs, Attila; Crosby, Seth D; Saftig, Paul; Diwan, Abhinav

    2015-01-01

    Autophagy, a lysosomal degradative pathway, is potently stimulated in the myocardium by fasting and is essential for maintaining cardiac function during prolonged starvation. We tested the hypothesis that intermittent fasting protects against myocardial ischemia-reperfusion injury via transcriptional stimulation of the autophagy-lysosome machinery. Adult C57BL/6 mice subjected to 24-h periods of fasting, every other day, for 6 wk were protected from in-vivo ischemia-reperfusion injury on a fed day, with marked reduction in infarct size in both sexes as compared with nonfasted controls. This protection was lost in mice heterozygous null for Lamp2 (coding for lysosomal-associated membrane protein 2), which demonstrate impaired autophagy in response to fasting with accumulation of autophagosomes and SQSTM1, an autophagy substrate, in the heart. In lamp2 null mice, intermittent fasting provoked progressive left ventricular dilation, systolic dysfunction and hypertrophy; worsening cardiomyocyte autophagosome accumulation and lack of protection to ischemia-reperfusion injury, suggesting that intact autophagy-lysosome machinery is essential for myocardial homeostasis during intermittent fasting and consequent ischemic cardioprotection. Fasting and refeeding cycles resulted in transcriptional induction followed by downregulation of autophagy-lysosome genes in the myocardium. This was coupled with fasting-induced nuclear translocation of TFEB (transcription factor EB), a master regulator of autophagy-lysosome machinery; followed by rapid decline in nuclear TFEB levels with refeeding. Endogenous TFEB was essential for attenuation of hypoxia-reoxygenation-induced cell death by repetitive starvation, in neonatal rat cardiomyocytes, in-vitro. Taken together, these data suggest that TFEB-mediated transcriptional priming of the autophagy-lysosome machinery mediates the beneficial effects of fasting-induced autophagy in myocardial ischemia-reperfusion injury. PMID:26103523

  5. Taxonomic minimalism.

    Science.gov (United States)

    Beattle, A J; Oliver, I

    1994-12-01

    Biological surveys are in increasing demand while taxonomic resources continue to decline. How much formal taxonomy is required to get the job done? The answer depends on the kind of job but it is possible that taxonomic minimalism, especially (1) the use of higher taxonomic ranks, (2) the use of morphospecies rather than species (as identified by Latin binomials), and (3) the involvement of taxonomic specialists only for training and verification, may offer advantages for biodiversity assessment, environmental monitoring and ecological research. As such, formal taxonomy remains central to the process of biological inventory and survey but resources may be allocated more efficiently. For example, if formal Identification is not required, resources may be concentrated on replication and increasing sample sizes. Taxonomic minimalism may also facilitate the inclusion in these activities of important but neglected groups, especially among the invertebrates, and perhaps even microorganisms. Copyright © 1994. Published by Elsevier Ltd.

  6. The ischemic perinatal brain damage

    International Nuclear Information System (INIS)

    Crisi, G.; Mauri, C.; Canossi, G.; Della Giustina, E.

    1986-01-01

    The term ''hypoxic-ischemic encephalopathy'' covers a large part of neonatal neuropathology including the various forms of intracerebral haemorrhage. In the present work the term is confined to ischemic brain edema and actual infarction, be it diffuse or focal. Eighteen newborns with CT evidence of ischemic brain lesions and infarctual necrosis were selected. Emphasis is placed on current data on neuropathology of ischemic brain edema and its CT appearance. Particular entities such as periventricular leukomalacia and multicystic encephalopathy are discussed. Relationship between CT and temporal profile of cerebral damage is emphasized in order to predict the structural sequelae and the longterm prognosis

  7. Development of Bioartificial Myocardium Using Stem Cells and Nanobiotechnology Templates

    Directory of Open Access Journals (Sweden)

    Juan Carlos Chachques

    2011-01-01

    Full Text Available Cell-based regenerative therapy is undergoing experimental and clinical trials in cardiology, in order to limit the consequences of decreased contractile function and compliance of damaged ventricles following myocardial infarction. Over 1000 patients have been treated worldwide with cell-based procedures for myocardial regeneration. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit adverse postischemic remodelling, and improve diastolic function. The development of a bioartificial myocardium is a new challenge; in this approach, tissue-engineered procedures are associated with cell therapy. Organ decellularization for bioscaffolds fabrication is a new investigated concept. Nanomaterials are emerging as the main candidates to ensure the achievement of a proper instructive cellular niche with good drug release/administration properties. Investigating the electrophysiological properties of bioartificial myocardium is the challenging objective of future research, associating a multielectrode network to provide electrical stimulation could improve the coupling of grafted cells and scaffolds with host cardiomyocytes. In summary, until now stem cell transplantation has not achieved clear hemodynamic benefits for myocardial diseases. Supported by relevant scientific background, the development of myocardial tissue engineering may constitute a new avenue and hope for the treatment of myocardial diseases.

  8. The study of myocardial ischemic quality with weighted-subtraction-bull's-eye analysis

    International Nuclear Information System (INIS)

    Chen Wuduan; Tian Jiahe; Hou Qingtian

    1993-01-01

    Weighted-Subtraction-Bull's-eye analysis was studied in 33 normal subjects and 58 patients with coronary artery disease after dipyridamole 99m Tc-MIBI myocardial SPECT imaging. Two kinds of Bull's-eye were produced: (1) subtract rest from 1.2 times dipyridamole from 1.2 times rest Bull's-eye; (2) subtract dipyridamole Bull's-eye. The results showed that the weighted-subtraction-Bull's-eye could clearly displayed the location and puality of ischemic myocardium. And also 74% segments showed so called combined ischemic i.e the blood perfusion reduced, increased and sustained simultaneously after dipyridamole. Therefore weighted-subtraction-Bull's-eye analysis had provided a new method for determination of the quality of ischemia

  9. Probability mapping of scarred myocardium using texture and intensity features in CMR images

    Science.gov (United States)

    2013-01-01

    Background The myocardium exhibits heterogeneous nature due to scarring after Myocardial Infarction (MI). In Cardiac Magnetic Resonance (CMR) imaging, Late Gadolinium (LG) contrast agent enhances the intensity of scarred area in the myocardium. Methods In this paper, we propose a probability mapping technique using Texture and Intensity features to describe heterogeneous nature of the scarred myocardium in Cardiac Magnetic Resonance (CMR) images after Myocardial Infarction (MI). Scarred tissue and non-scarred tissue are represented with high and low probabilities, respectively. Intermediate values possibly indicate areas where the scarred and healthy tissues are interwoven. The probability map of scarred myocardium is calculated by using a probability function based on Bayes rule. Any set of features can be used in the probability function. Results In the present study, we demonstrate the use of two different types of features. One is based on the mean intensity of pixel and the other on underlying texture information of the scarred and non-scarred myocardium. Examples of probability maps computed using the mean intensity of pixel and the underlying texture information are presented. We hypothesize that the probability mapping of myocardium offers alternate visualization, possibly showing the details with physiological significance difficult to detect visually in the original CMR image. Conclusion The probability mapping obtained from the two features provides a way to define different cardiac segments which offer a way to identify areas in the myocardium of diagnostic importance (like core and border areas in scarred myocardium). PMID:24053280

  10. Angiographically demonstrated coronary collaterals predict residual viable myocardium in patients with chronic myocardial infarction. A regional metabolic study

    International Nuclear Information System (INIS)

    Fukai, Masumi; Ii, Masaaki; Nakakoji, Takahiro

    2000-01-01

    Angiographical demonstration of coronary collateral circulation may suggest the presence of residual viable myocardium. The development of coronary collaterals was judged according to Rentrop's classification in 37 patients with old anteroseptal myocardial infarction and 13 control patients with chest pain syndrome. The subjects with myocardial infarction were divided into 2 groups: 17 patients with the main branch of the left coronary artery clearly identified by collateral blood flow from the contralateral coronary artery [Coll (+) group, male/female 10/7, mean age 56.6 years] and 20 patients with obscure coronary trunk [Coll (-) group, male/female 16/4, mean age 54.9 years]. Thallium-201 myocardial scintigraphy and examination of local myocardial metabolism were carried out by measuring the flux of lactic acid under dipyridamole infusion load. Coronary stenosis of 99% or total occlusion was found in only 5 of 20 patients (25%) in the Coll (-) group but in 16 of 17 patients (94%) in the Coll (+) group (p<0.001). Redistribution of myocardial scintigraphy was found in 11 of 15 patients (73%) in the Coll (+) group, but only 3 of 18 patients (17%) in the Coll (-) group (p<0.01). The myocardial lactic acid extraction rate was -13.2±17.0% in the Coll (+) group, but 9.1±13.2% in the Coll (-) group (p<0.001). These results suggest that coronary collateral may contribute to minimizing the infarct area and to prediction of the presence of viable myocardium. (author)

  11. Proteomic analysis identifies mitochondrial metabolic enzymes as major discriminators between different stages of the failing human myocardium

    DEFF Research Database (Denmark)

    Urbonavicius, Sigitas; Wiggers, Henrik; Bøtker, Hans Erik

    2009-01-01

    Our aim was to identify patterns in differentially regulated proteins associated with the progression of chronic heart failure. We specifically studied proteomics in chronic reversibly (RDM) and irreversibly dysfunctional myocardium (IRDM), as well as end-stage failing myocardium (ESFM).......Our aim was to identify patterns in differentially regulated proteins associated with the progression of chronic heart failure. We specifically studied proteomics in chronic reversibly (RDM) and irreversibly dysfunctional myocardium (IRDM), as well as end-stage failing myocardium (ESFM)....

  12. Temperature dependence of the kinetics of isometric myocardium relaxation

    Energy Technology Data Exchange (ETDEWEB)

    Izakov, V.Ya.; Bykov, B.L.; Kimmelman, I.Ya.

    1981-11-01

    The dependence of the exponential decay constant expressing the isometric relaxation of the myocardium on temperature is investigated in animals with various specific contents of myocardial sarcoplasmic reticulum. Experiments were performed on cardiac ventricles and atria isolated from rabbits, frogs and turtles and electrically stimulated to produce maximal contraction at temperatures from 10 to 35 C. Arrhenius plots derived from the data are found to be linear in the myocardia of the rabbit and frog, with a greater activation energy for the relaxation found in the rabbit. The Arrhenius plot for the turtle, which has a sarcoplasmic reticulum content intermediate between those of the frog and rabbit, corresponds to two straight lines with different activation energies. Results thus support the hypothesis of two separate mechanisms of calcium removal, involving the sarcoplasmic reticulum and cellular membrane, in muscle relaxation.

  13. Radionuclide imaging in primary and secondary disorders of the myocardium

    International Nuclear Information System (INIS)

    Follansbee, W.P.

    1987-01-01

    The list of all potential causes of myocardial disease or injury is an extensive one: a condensed version is presented. Conceptually these processes can be categorized into those which are, or appear to be, primary to the myocardium and those which secondarily involve it. Nuclear imaging procedures, particularly those used to assess ventricular function, are in a general sense potentially applicable to the clinical evaluation of any of these entities. In certain of these conditions, however, nuclear cardiac procedures have a demonstrated or potential additional and more specific role for the diagnosis and quantification of the entity. A number of these, including coronary artery disease, valvular heart disease, cor pulmonale, and myocardial trauma, are the topics of other chapters and, therefore, are not dealt with further here. The remainder of the myocardial disorders in which nuclear imaging procedures have a recognized or potential specific role are the focus of this discussion

  14. Pathomorphological Changes of the Myocardium in Canine Dilated Cardiomyopathy (DCM

    Directory of Open Access Journals (Sweden)

    Janus Izabela

    2015-04-01

    Full Text Available The study was conducted on ventricular and atrial wall preparations from 11 dogs with clinically diagnosed dilated cardiomyopathy. After fixation, the specimens were stained with haematoxylin and eosin and Masson-Goldner trichrome technique. Parenchymal changes (fibrosis and fatty infiltration, vascular changes (congestion and coronary vessel wall hypertrophy, degenerative changes (loss of striation, changes in cardiomycyte and nuclei structure, and presence of inflammatory infiltrates (mononuclear and polynuclear were estimated. Complex histological changes in both ventricular and atrial muscles were shown. It was not determined whether the processes occurring in the myocardium have a primary character, or are a consequence of developing heart failure. Such issues will be put under further and more detailed examination.

  15. Direct effects of smoking on the heart: silent ischemic disturbances of coronary flow

    International Nuclear Information System (INIS)

    Deanfield, J.E.; Shea, M.J.; Wilson, R.A.; Horlock, P.; de Landsheere, C.M.; Selwyn, A.P.

    1986-01-01

    Cigarette smoking is strongly associated with ischemic heart disease and acute coronary events. The effect of smoking a single cigarette on regional myocardial perfusion was studied in 13 chronic smokers with typical stable angina pectoris using positron emission tomography and rubidium-82 ( 82 Rb). Findings were compared with the effects of physical exercise. After exercise, 8 patients (61%) had angina, ST depression and abnormal regional myocardial perfusion. Uptake of 82 Rb increased from 49 +/- 8 to 60 +/- 7 in remote myocardium, but decreased from 46 +/- 3 to 37 +/- 5 in an ischemic area. The remaining 5 patients (39%) had homogeneous increases in 82 Rb uptake without angina or ST depression. After smoking, 6 of the 8 patients with positive exercise test responses had a decrease in 82 Rb uptake, from 47 +/- 3 to 35 +/- 6 in the same segment of myocardium affected during exercise. However, in contrast to exercise, the events during smoking were largely silent. The absolute decreases in regional 82 Rb uptake after smoking occurred at significantly lower levels of myocardial oxygen demand than after exercise. This suggests that an impairment of coronary blood supply is responsible. Thus, in smokers with coronary artery disease, each cigarette can cause profound silent disturbances of regional myocardial perfusion that are likely to occur frequently during daily life. Such repeated insults may represent an important mechanism linking smoking with coronary events

  16. Influence of risk area size and location on native collateral resistance and ischemic zone perfusion

    International Nuclear Information System (INIS)

    Gumm, D.C.; Cooper, S.M.; Thompson, S.B.; Marcus, M.L.; Harrison, D.C.

    1988-01-01

    To examine the effect of risk area size on collateral resistance and ichemic region perfusion, the authors produced different sized risk areas by occluding either the left anterior descending (LAD) or the circumflex (Cx) coronary artery at different sites. The most proximal occlusion of the LAD and Cx produced risk areas of 43 ± 5 and 36 ± 2% of left ventricular (LV) mass, respectively, whereas distal LAD and Cx occlusions produced risk areas of 13 ± 2 and 17 ± 2% of LV weight, respectively. Although total collateral flow was highest to the largest risk areas, collateral flow per 100 g of ischemic myocardium was 80% higher to the small LAD risk area compared with the large LAD risk area and 43% higher to the small Cx risk area compared with the large Cx risk area. Collateral resistance, calculated from the transcollateral pressure and perfusion per 100 g of myocardium was significantly lower in the small risk areas than in the large ones. They examined the effect of risk area location on collateral perfusion and resistance. These experiments show that collateral resistance is influenced both by ischemic region size and location. Small risk areas receive more collateral flow per mass of tissue than large risk areas, and apical risk areas receive greater quantities of collateral flow than those located at the base. These data may explain why small risk areas often do not develop infarction after coronary occlusion

  17. Quantitative circumferential strain analysis using adenosine triphosphate-stress/rest 3-T tagged magnetic resonance to evaluate regional contractile dysfunction in ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Masashi, E-mail: m.nakamura1230@gmail.com [Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon-city, Ehime 791-0295 (Japan); Kido, Tomoyuki [Department of Radiology, Saiseikai Matsuyama Hospital, Ehime 791-0295 (Japan); Kido, Teruhito; Tanabe, Yuki; Matsuda, Takuya; Nishiyama, Yoshiko; Miyagawa, Masao; Mochizuki, Teruhito [Department of Radiology, Ehime University Graduate School of Medicine, Shitsukawa, Toon-city, Ehime 791-0295 (Japan)

    2015-08-15

    Highlights: • Infarcted segments could be differentiated from non-ischemic and ischemic segments with high sensitivity and specificity under at rest conditions. • The time-to-peak circumferential strain values in infarcted segments were more significantly delayed than those in non-ischemic and ischemic segments. • Both circumferential strain and circumferential systolic strain rate values under ATP-stress conditions were significantly lower in ischemic segments than in non-ischemic segments. • Subtracting stress and rest circumferential strain had a higher diagnostic capability for ischemia relative to only utilizing rest or ATP-stress circumferential strain values. • A circumferential strain analysis using tagged MR can quantitatively assess contractile dysfunction in ischemic and infarcted myocardium. - Abstract: Purpose: We evaluated whether a quantitative circumferential strain (CS) analysis using adenosine triphosphate (ATP)-stress/rest 3-T tagged magnetic resonance (MR) imaging can depict myocardial ischemia as contractile dysfunction during stress in patients with suspected coronary artery disease (CAD). We evaluated whether it can differentiate between non-ischemia, myocardial ischemia, and infarction. We assessed its diagnostic performance in comparison with ATP-stress myocardial perfusion MR and late gadolinium enhancement (LGE)-MR imaging. Methods: In 38 patients suspected of having CAD, myocardial segments were categorized as non-ischemic (n = 485), ischemic (n = 74), or infarcted (n = 49) from the results of perfusion MR and LGE-MR. The peak negative CS value, peak circumferential systolic strain rate (CSR), and time-to-peak CS were measured in 16 segments. Results: A cutoff value of −12.0% for CS at rest allowed differentiation between infarcted and other segments with a sensitivity of 79%, specificity of 76%, accuracy of 76%, and an area under the curve (AUC) of 0.81. Additionally, a cutoff value of 477.3 ms for time-to-peak CS at rest

  18. MYOCARDIAL PERFUSION ASSESSMENT IN FORECASTING EFFECT OF CORONARY ANGIOPLASTY IN PATIENTS WITH ISCHEMIC CHRONIC HEART FAILURE

    Directory of Open Access Journals (Sweden)

    A. B. Mironkov

    2015-01-01

    Full Text Available Aim. To define influence of the left ventricle (LV perfusion defects on the clinical status dynamics after coronary angioplasty in patients with the expressed myocardium dysfunction of ischemic etiology. Materials and methods. Examined 86 patients (81 men and 5 women aged from 46 to 73 years before and in 2–3 days after percutaneous coronary intervention with diagnosis: CAD, CHF with NYHA class III–IV, echocardiography parameters of LV: ejection fraction less than 40%, end-diastolic volume is more than 200 ml. Perfusion defects of myocardium estimated with use of ECG-gated single photon emission computed tomography. Predictors were defined: perfusion defects on LV apex (in score, perfusion defects in the area of LAD, LCx and RCA (%, the LV global perfusion defects (in score and %. Results. In 42% of cases 6-minute walk test increased to 3 times; The NYHA class decreased by 2 classes (group 1. In 28 cases 6-minute walk test increased to 2 times and the NYHA class decreased on 1 class. In 22 patients 6-minute walk test increased less than 50% of reference values and there was no dynamics NYHA class (50 patients of the group 2. Initial extent of LV global perfusion defects in group 1 – 41,2 ± 4,0%, in group 2 – 58,3 ± 2,4% (р = 0,0004. Similar values are received for perfusion indicators in the area of LAD and the LV apex. Prevalence of myocardial perfusion defects at rest reflects prevalence of a cardiosclerosis in a cardiac muscle. Conclusion. Degree of LV myocardial perfusion defects in patients with the expressed heart failure of ischemic etiology is the key indicator influencing clinical efficiency of coronary angioplasty. Critical size for definition of the favorable forecast of revascularization are 60% and more perfusion defects testifying that in a cardiac muscle the focal cardiosclerosis prevails over the functioning myocardium

  19. The alteration of interelemental ratios in myocardium under the congenital heart disease (SRXRF)

    International Nuclear Information System (INIS)

    Trunova, V.A.; Zvereva, V.V.; Okuneva, G.N.; Levicheva, E.N.

    2007-01-01

    It is the myocardium that bears the basic functional loading during heart working, including muscle contractility and enzyme activity. The elemental concentrations in myocardium tissue of heart were determined by SRXRF technique. Our investigation is systematical: the elemental content in each compartment (left and right ventricles, left and right auricles) of hearts of healthy and diseased children (congenital heart diseases, transposition of main vessels (TMV)) was analyzed. The elemental distribution in myocardium of four heart chambers of human fetuses was also analyzed. Following elements were determined: S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, Sr. It was revealed that the elemental concentrations in myocardium of both ventricles are almost constant in heart of fetuses and healthy children. The transition from pre-natal study (fetus) to post-natal study is accompanied by the redistribution of chemical elements in myocardium. The higher concentrations of S, Fe, Ca, Sr and Cu in myocardium of children are observed, the content of K, Br, Rb and especially Se is lower than in heart of fetuses. The elemental distribution in myocardium of children TMV is considerably different in comparison with the healthy children: the higher levels of Cu are observed. The content of Se is lower

  20. Diagnostic evaluation of ischemic heart disease by X-ray computed tomography and magnetic resonance imaging

    International Nuclear Information System (INIS)

    Masuda, Yoshiaki; Kobayashi, Shiro; Takasu, Junichiro; Sakakibara, Makoto; Imai, Hitoshi; Aoyagi, Yutaka; Morooka, Nobuhiro; Watanabe, Shigeru; Inagaki, Yoshiaki

    1987-01-01

    To assess the usefulness of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) in detecting and evaluating ischemic heart disease, conventional and enhanced CT were performed for 180 patients (150 with transmural infarction, 12 with subendocardial infarction, and 18 with angina pectoris). MRI examinations were performed for 38 patients (31 with transmural infarction, three with subendocardial infarction, and four with angina pectoris). With enhanced CT, two findings in the myocardium were direct evidence of myocardial infarction: 1) filling defects on the early scans, and 2) late enhancement of the myocardium on the delayed scans. The former were observed mainly at the sites of recent anterior myocardial infarction and the latter were seen in about half of the patients with recent and remote anterior myocardial infarctions. However, these findings were inadequately imaged in patients with inferoposterior infarction and subendocardial infarction. Among 137 patients with transmural infarction, enhanced CT revealed left ventricular aneurysms in 51 (37 %) and ventricular thrombi in 26 (19 %). ECG-gated MRI apparatus having a superconducting magnetic operating at 0.25 Tesla was used, and data for this study were collected using the single-slice spin echo technique. In eight of nine patients with acute myocardial infarction, gated MRI demonstrated the infarcted myocardium as regions of high signal intensity relative to that of the adjacent normal myocardium. Such a difference in MRI signal intensity was scarcely recognized in the chronic stage of myocardial infarction, but the indirect findings of infarction, such as regional wall thinning, wall motion disturbances, left ventricular aneurysms, and ventricular thrombi were easily detected using MRI. No characteristic finding was obtained by CT or MRI in patients with angina pectoris. (author)

  1. Remote Ischemic Conditioning

    Science.gov (United States)

    Heusch, Gerd; Bøtker, Hans Erik; Przyklenk, Karin; Redington, Andrew; Yellon, Derek

    2014-01-01

    In remote ischemic conditioning (RIC) brief, reversible episodes of ischemia with reperfusion in one vascular bed, tissue or organ confer a global protective phenotype and render remote tissues and organs resistant to ischemia/reperfusion injury. The peripheral stimulus can be chemical, mechanical or electrical and involves activation of peripheral sensory nerves. The signal transfer to the heart or other organs is through neuronal and humoral communications. Protection can be transferred, even across species, with plasma-derived dialysate and involves nitric oxide, stromal derived factor-1α, microRNA-144, but also other, not yet identified factors. Intracardiac signal transduction involves: adenosine, bradykinin, cytokines, and chemokines, which activate specific receptors; intracellular kinases; and mitochondrial function. RIC by repeated brief inflation/deflation of a blood pressure cuff protects against endothelial dysfunction and myocardial injury in percutaneous coronary interventions, coronary artery bypass grafting and reperfused acute myocardial infarction. RIC is safe and effective, noninvasive, easily feasible and inexpensive. PMID:25593060

  2. Hemichorea after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Sadullah Saglam

    2016-03-01

    Full Text Available The deterioration of the balance between direct and indirect ways in the basal ganglia causes chorea. The lesions of contralateral basal ganglia, thalamus or the connection of them all together are responsible for this. Chorea can be observed during the course of metabolic and vascular diseases, neurodegenerative or hereditary diseases. Hyperkinetic movement disorders after acute ischemic stroke are reported as rare; however, hemichorea is the most frequent developing disorder of hyperkinetic movement as a result of cerebrovascular disease. In this case report, we presented two case who applied us with choreiform movements in his left half of the body after acute thalamic stroke. [Cukurova Med J 2016; 41(0.100: 29-32

  3. Action of iloprost and PGE1 on global ischemic and reperfused myocardium: a 31P-NMR-study.

    Science.gov (United States)

    Pissarek, M; Gründer, W; Keller, T; Goos, H; Mest, H J; Krause, E G

    1988-01-01

    The influence of iloprost, PGE1 and of the combined application of iloprost and PGE1 on high energy phosphate contents was investigated in isolated rat hearts perfused aerob at 37 degrees C in Langendorff mode. Changes in creatine phosphate, ATP and inorganic phosphate were registered during 20 minutes of global ischemia and 56 minutes of reperfusion with 31P-NMR-spectroscopic methods starting drug application prior to ischemia simultaneously with onset of heart perfusion. Most effective in preservation of high energy phosphates was the combined application of PGE1 and iloprost resulting in a creatine phosphate/inorganic phosphate ratio of 103.2 +/- 30.9% of pre-ischemia values compared to 52.5 +/- 6.1% in control group without drug application 0-5 minutes after onset of reperfusion, 148.8 +/- 24.8% vs 78.8 +/- 15.2% at 6-11 minutes of reperfusion and 116.6 +/- 16% vs 68.9 +/- 12.7% at 12-17 minutes of reperfusion. The same trend was observed employing ATP/inorganic phosphate ratio. The improved energy state in reperfused hearts following application of PGE1 and iloprost in combination is presumed to be supported by a reduction of the loss of high energy phosphates (HEP) during global ischemia and by a cytoprotective effect of iloprost immediately after starting reperfusion.

  4. Diagnosis of Non-compacted Myocardium of the Left Ventricle in Children

    Directory of Open Access Journals (Sweden)

    I.B. Yershova

    2014-05-01

    Full Text Available The authors presented a review of published literature data on rare congenital abnormalities in children — a non-compacted myocardium of the left ventricle, which refers to unclassified cardiomyopathy. This pathology by the American Heart Association classification relates to genetic cardiomyopathy. Non-compacted myocardium of the left ventricle in children develops due to violation of myocardial induration of the fetus in utero. Diagnosis of the disease is difficult due to the lack of specific clinical signs. The authors also presented a clinical case of non-compacted left ventricular myocardium in 6-year-old girl.

  5. Improved identification of viable myocardium using second harmonic imaging during dobutamine stress echocardiography

    NARCIS (Netherlands)

    F. Sozzi (Fabiola); D. Poldermans (Don); J.J. Bax (Jeroen); A. Elhendy (Abdou); E.C. Vourvouri (Eleni); R. Valkema (Roelf); J. de Sutter; A.F.L. Schinkel (Arend); A. Borghetti; J.R.T.C. Roelandt (Jos)

    2001-01-01

    textabstractOBJECTIVE: To determine whether, compared with fundamental imaging, second harmonic imaging can improve the accuracy of dobutamine stress echocardiography for identifying viable myocardium, using nuclear imaging as a reference. PATIENTS: 30 patients with chronic left

  6. Pathological mechanism for delayed hyperenhancement of chronic scarred myocardium in contrast agent enhanced magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Jian Wang

    Full Text Available OBJECTIVES: To evaluate possible mechanism for delayed hyperenhancement of scarred myocardium by investigating the relationship of contrast agent (CA first pass and delayed enhancement patterns with histopathological changes. MATERIALS AND METHODS: Eighteen pigs underwent 4 weeks ligation of 1 or 2 diagonal coronary arteries to induce chronic infarction. The hearts were then removed and perfused in a Langendorff apparatus. The hearts firstly experienced phosphorus 31 MR spectroscopy. The hearts in group I (n = 9 and II (n = 9 then received the bolus injection of Gadolinium diethylenetriamine pentaacetic acid (0.05 mmol/kg and gadolinium-based macromolecular agent (P792, 15 µmol/kg, respectively. First pass T2* MRI was acquired using a gradient echo sequence. Delayed enhanced T1 MRI was acquired with an inversion recovery sequence. Masson's trichrome and anti- von Willebrand Factor (vWF staining were performed for infarct characterization. RESULTS: Wash-in of both kinds of CA caused the sharp and dramatic T2* signal decrease of scarred myocardium similar to that of normal myocardium. Myocardial blood flow and microvessel density were significantly recovered in 4-week-old scar tissue. Steady state distribution volume (ΔR1 relaxation rate of Gd-DTPA was markedly higher in scarred myocardium than in normal myocardium, whereas ΔR1 relaxation rate of P792 did not differ significantly between scarred and normal myocardium. The ratio of extracellular volume to the total water volume was significantly greater in scarred myocardium than in normal myocardium. Scarred myocardium contained massive residual capillaries and dilated vessels. Histological stains indicated the extensively discrete matrix deposition and lack of cellular structure in scarred myocardium. CONCLUSIONS: Collateral circulation formation and residual vessel effectively delivered CA into scarred myocardium. However, residual vessel without abnormal hyperpermeability allowed Gd

  7. Probing myocardium biomechanics using quantitative optical coherence elastography

    Science.gov (United States)

    Wang, Shang; Lopez, Andrew L.; Morikawa, Yuka; Tao, Ge; Li, Jiasong; Larina, Irina V.; Martin, James F.; Larin, Kirill V.

    2015-03-01

    We present a quantitative optical coherence elastographic method for noncontact assessment of the myocardium elasticity. The method is based on shear wave imaging optical coherence tomography (SWI-OCT), where a focused air-puff system is used to induce localized tissue deformation through a low-pressure short-duration air stream and a phase-sensitive OCT system is utilized to monitor the propagation of the induced tissue displacement with nanoscale sensitivity. The 1-D scanning of M-mode OCT imaging and the application of optical phase retrieval and mapping techniques enable the reconstruction and visualization of 2-D depth-resolved shear wave propagation in tissue with ultra-high frame rate. The feasibility of this method in quantitative elasticity measurement is demonstrated on tissue-mimicking phantoms with the estimated Young's modulus compared with uniaxial compression tests. We also performed pilot experiments on ex vivo mouse cardiac muscle tissues with normal and genetically altered cardiomyocytes. Our results indicate this noncontact quantitative optical coherence elastographic method can be a useful tool for the cardiac muscle research and studies.

  8. Reproducibility of P-31 spectroscopic imaging of normal human myocardium

    International Nuclear Information System (INIS)

    Tavares, N.J.; Chew, W.; Auffermann, W.; Higgins, C.B.

    1988-01-01

    To assess reproducibility of P-31 MR spectroscopy of human myocardium, ten normal male volunteers were studied on two separate occasions. Spectra were acquired on a clinical 1.5-T MR imaging unit (Signa, General Electric) using a one-dimensional gated spectroscopic imaging sequence (matrix size, 32 X 256) over 20 minutes. Peaks in the adenosine triphosphate (ATP) region, phosphocreatine (PCR), phosphodiesters (PD), and peaks attributable to 2,3 diphosphoglycerate from blood were observed. Interindividual and intraindividual variability expressed as standard errors of the mean (mean +- SEM) were 1.54 +- 0.04 (variability among subjects) and 0.04 (variability between first and second studies) for PCR/β ATP; 0.97 +- 0.18 and 0.06 for PD/β ATP; and 0.62 +- 0.10 and 0.05 for PD/PCR, respectively. In conclusion, P-31 MR spectroscopy yields consistent and reproducible myocardial spectra that might be useful in the future for the evaluation and monitoring of cardiac disease

  9. Stereological Cell Morphometry In Right Atrium Myocardium Of Primates

    Science.gov (United States)

    Mandarim-De-Lacerda, Carlos A...; Hureau, Jacques

    1986-07-01

    The mechanism by which the cardiac impulse is propagated in normal hearts from its origin in the sinus node to the atrio-ventricular node has not been agreed on fully. We studied the "internodal posterior tract" through the crista terminalis by light microscopy and stereological morphometry. The hearts of 12 Papio cynocephalus were perfused , after sacrifice,with phosphate-buffered formol saline. The regions of the crista terminalis (CT), interatrial septum (IAS), atrioventricular bundle (AVB) and interventricular septum (IVS) were cut off and embedded in paraplast and sectioned (10 4m). The multipurpose test system M 42 was superimposed over the photomicrographs (1,890 points test, ESR = 2%) to the stereological computing. The quantitative results show that the cells from CT were more closely relationed with IAS cells than others cells (IVS and AVB cells). This results are not a morphological evidence to establish the specificity of the "internodal posterior tract". The cellular arrangement and anatomical variation in CT myocardium is very important.

  10. The myocardium functional reserve indicators in junior children with recurrent acute upper respiratory tract infection

    Directory of Open Access Journals (Sweden)

    L.S. Ovcharenko

    2017-02-01

    Full Text Available Background. The problem of early diagnosis of cardiovascular diseases in children is relevant throughout the world and in Ukraine, as in childhood the health and quality of life of an adult are formed. The psychoemotional stress in junior children as well as increasingly complicating school curriculum, information overload with electronic gadgets, increased frequency of colds in children cause physical inactivity. In addition, infectious agents have a toxic effect on the myocardium, altering its functional state. All these together adversely affect the formation and development of the cardiovascular and respiratory systems of children. The aim was to study the functional reserve of the myocardium in junior children, depending on the frequency of upper respiratory tract infection (URTI. Materials and methods. The study examined 1109 children aged 6 to 9 years old. The URTI incidence was analyzed depending on the age. In the study, the children were divided into two groups. Group 1 consisted of the children with URTI — 210. Group 2 involved the children with occasional URTI — 899. Results. Among 210 surveyed children with upper respiratory infections 171 schoolboys (81.4 % had reduced functional reserve of the myocardium, which is consistent with findings from other studies. In children aged 7 and 9 years old, the number of reduced functional reserve of the myocardium varies from 70 to 82 % in seven-year children, among the schoolboys aged 6 and 8 years old the incidence of reduced functional reserve of the myocardium increased from 83 to 100 % in six-year children. Conclusions. Children with URTI have a reduced functional reserve of the myocardium. Children with episodic URTI have higher rates of functional reserve of the myocardium, therefore reducing the incidence of URTI will lead to the improvement of the myocardium functional state.

  11. Perfusion single photon emission computed tomography of myocardium with 99mTc-tetra-phosmine (Myoview)

    International Nuclear Information System (INIS)

    Khusainova, Sh.K.; Zholdybaj, Zh.; Potapov, A.V.; Karaev, O.S.; Akhmetova, G.R.

    2003-01-01

    The aim of the work is study of diagnostic valuation of myocardium scintigraphy with help of the 99m Tc-tetrophosmin, Myoview in determination of latent coronary blood-circulation destabilization in liquidators of the Chernobyl accident (LChA) and persons living in the Semipalatinsk test site (STS) region. The perfusion myocardium scintigraphy was made to 71 patients (5 women and 66 men) from those - 33 LChA and 37 - residents of STS region. The examination was carried out in 'ADAC Genesys Epic' apparatus (USA). Mean age of the patients was 46.3±2.3 years old. In the result of examination the left ventricle myocardium perfusion reduction on 30 % and more was revealed. The distribution of radiopharmaceutical by the myocardium parts were relatively proportional both with pharmacologic load (ATF, dipiridamol) and the rest in 48 (67.7 %) patients. So, the 99m Tc-tetrophosmin, Myoview pharmaceutical allows with high rate estimate the myocardium perfusion and get a high qualitative images, that permits to identify localization, character and distribution of myocardium perfusion reduction in the revealed areas. In the result of myocardine scintigraphy with the pharmacologic load trial conducting the both the latent coronary blood-circulation destabilization forms and the incoming ones were differentiated

  12. Quantitation of the critically ischemic zone at risk during acute coronary occlusion using PET

    International Nuclear Information System (INIS)

    Merhige, M.; Garza, D.; Sease, D.; Rowe, R.W.; Tewson, T.; Emran, A.; Bolomey, L.; Gould, K.L.

    1991-01-01

    Critical myocardial ischemia has been defined experimentally during acute coronary occlusion as flow reduction of 50% or more since cellular ATP depletion begins to occur beyond this flow reduction threshold, placing tissue at risk of cellular injury. To test the hypothesis that critically ischemic fractional left ventricular mass can be measured noninvasively with PET, nine dogs were imaged in a multi-slice positron camera using the perfusion tracer 13N-ammonia, while radiolabeled microspheres were injected into the left atrium during acute coronary occlusion. Images were processed using a 50% threshold and the size of the resulting perfusion defect was expressed as a fraction of total left ventricular image volume. The critically ischemic left ventricular fraction determined in vitro from the microsphere perfusion data, ranged from 5% to 30% of the total left ventricular weight and correlated closely with that determined noninvasively by PET with r = 0.94 (y = 1.05X - 2.0%). The authors conclude that the fraction of left ventricular myocardium rendered critically ischemic during acute coronary occlusion can be measured accurately and noninvasively in vivo using perfusion imaging with positron emission tomography

  13. MRI in ischemic heart disease

    International Nuclear Information System (INIS)

    Hazirolan, T.

    2012-01-01

    Full text: The role of magnetic resonance imaging in the evaluation of ischemic heart disease has increased over the last years. Cardiac MRI is the only imaging modality that provides 'one stop shop' assessment. Information about ventricular function, myocardial ischemia and myocardial viability can be obtained in a single cardiac MRI session. Additionally, Cardiac MRI has become a gold standard method in evaluation of myocardial viability and in assessment of ventricular mass and function. As a result, cardiac MRI enable radiologist to comprehensively assess ischemic heart disease. The aim of this presentation is to provide the reader a state-of-the art on how the newest cardiac MRI techniques can be used to study ischemic heart disease patients.

  14. MR imaging of ischemic penumbra

    International Nuclear Information System (INIS)

    Abe, Osamu; Aoki, Shigeki; Shirouzu, Ichiro; Kunimatsu, Akira; Hayashi, Naoto; Masumoto, Tomohiko; Mori, Harushi; Yamada, Haruyasu; Watanabe, Makoto; Masutani, Yoshitaka; Ohtomo, Kuni

    2003-01-01

    Cerebral ischemic stroke is one of the most fatal diseases despite current advances in medical science. Recent demonstration of efficacy using intravenous and intra-arterial thrombolysis demands therapeutic intervention tailored to the physiologic state of the individual tissue and stratification of patients according to the potential risks for therapies. In such an era, the role of the neuroimaging becomes increasingly important to evaluate the extent and location of tissues at risk of infarction (ischemic penumbra), to distinguish it from unsalvageable infarcted tissues or doomed hemorrhagic parenchyma. In this review, we present briefly the current role and limitation of computed tomography and conventional magnetic resonance imaging (MRI). We also present the possible applications of advanced MR techniques, such as diffusion and perfusion imaging, concentrating on the delineation or detection of ischemic penumbra

  15. [Minimally invasive coronary artery surgery].

    Science.gov (United States)

    Zalaquett, R; Howard, M; Irarrázaval, M J; Morán, S; Maturana, G; Becker, P; Medel, J; Sacco, C; Lema, G; Canessa, R; Cruz, F

    1999-01-01

    There is a growing interest to perform a left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD) on a beating heart through a minimally invasive access to the chest cavity. To report the experience with minimally invasive coronary artery surgery. Analysis of 11 patients aged 48 to 79 years old with single vessel disease that, between 1996 and 1997, had a LIMA graft to the LAD performed through a minimally invasive left anterior mediastinotomy, without cardiopulmonary bypass. A 6 to 10 cm left parasternal incision was done. The LIMA to the LAD anastomosis was done after pharmacological heart rate and blood pressure control and a period of ischemic pre conditioning. Graft patency was confirmed intraoperatively by standard Doppler techniques. Patients were followed for a mean of 11.6 months (7-15 months). All patients were extubated in the operating room and transferred out of the intensive care unit on the next morning. Seven patients were discharged on the third postoperative day. Duplex scanning confirmed graft patency in all patients before discharge; in two patients, it was confirmed additionally by arteriography. There was no hospital mortality, no perioperative myocardial infarction and no bleeding problems. After follow up, ten patients were free of angina, in functional class I and pleased with the surgical and cosmetic results. One patient developed atypical angina on the seventh postoperative month and a selective arteriography confirmed stenosis of the anastomosis. A successful angioplasty of the original LAD lesion was carried out. A minimally invasive left anterior mediastinotomy is a good surgical access to perform a successful LIMA to LAD graft without cardiopulmonary bypass, allowing a shorter hospital stay and earlier postoperative recovery. However, a larger experience and a longer follow up is required to define its role in the treatment of coronary artery disease.

  16. Bioprinting 3D microfibrous scaffolds for engineering endothelialized myocardium and heart-on-a-chip

    Science.gov (United States)

    Zhang, Yu Shrike; Arneri, Andrea; Bersini, Simone; Shin, Su-Ryon; Zhu, Kai; Goli-Malekabadi, Zahra; Aleman, Julio; Colosi, Cristina; Busignani, Fabio; Dell'Erba, Valeria; Bishop, Colin; Shupe, Thomas; Demarchi, Danilo; Moretti, Matteo; Rasponi, Marco; Dokmeci, Mehmet Remzi; Atala, Anthony; Khademhosseini, Ali

    2016-01-01

    Engineering cardiac tissues and organ models remains a great challenge due to the hierarchical structure of the native myocardium. The need of integrating blood vessels brings additional complexity, limiting the available approaches that are suitable to produce integrated cardiovascular organoids. In this work we propose a novel hybrid strategy based on 3D bioprinting, to fabricate endothelialized myocardium. Enabled by the use of our composite bioink, endothelial cells directly bioprinted within microfibrous hydrogel scaffolds gradually migrated towards the peripheries of the microfibers to form a layer of confluent endothelium. Together with controlled anisotropy, this 3D endothelial bed was then seeded with cardiomyocytes to generate aligned myocardium capable of spontaneous and synchronous contraction. We further embedded the organoids into a specially designed microfluidic perfusion bioreactor to complete the endothelialized-myocardium-on-a-chip platform for cardiovascular toxicity evaluation. Finally, we demonstrated that such a technique could be translated to human cardiomyocytes derived from induced pluripotent stem cells to construct endothelialized human myocardium. We believe that our method for generation of endothelialized organoids fabricated through an innovative 3D bioprinting technology may find widespread applications in regenerative medicine, drug screening, and potentially disease modeling. PMID:27710832

  17. Bioprinting 3D microfibrous scaffolds for engineering endothelialized myocardium and heart-on-a-chip.

    Science.gov (United States)

    Zhang, Yu Shrike; Arneri, Andrea; Bersini, Simone; Shin, Su-Ryon; Zhu, Kai; Goli-Malekabadi, Zahra; Aleman, Julio; Colosi, Cristina; Busignani, Fabio; Dell'Erba, Valeria; Bishop, Colin; Shupe, Thomas; Demarchi, Danilo; Moretti, Matteo; Rasponi, Marco; Dokmeci, Mehmet Remzi; Atala, Anthony; Khademhosseini, Ali

    2016-12-01

    Engineering cardiac tissues and organ models remains a great challenge due to the hierarchical structure of the native myocardium. The need of integrating blood vessels brings additional complexity, limiting the available approaches that are suitable to produce integrated cardiovascular organoids. In this work we propose a novel hybrid strategy based on 3D bioprinting, to fabricate endothelialized myocardium. Enabled by the use of our composite bioink, endothelial cells directly bioprinted within microfibrous hydrogel scaffolds gradually migrated towards the peripheries of the microfibers to form a layer of confluent endothelium. Together with controlled anisotropy, this 3D endothelial bed was then seeded with cardiomyocytes to generate aligned myocardium capable of spontaneous and synchronous contraction. We further embedded the organoids into a specially designed microfluidic perfusion bioreactor to complete the endothelialized-myocardium-on-a-chip platform for cardiovascular toxicity evaluation. Finally, we demonstrated that such a technique could be translated to human cardiomyocytes derived from induced pluripotent stem cells to construct endothelialized human myocardium. We believe that our method for generation of endothelialized organoids fabricated through an innovative 3D bioprinting technology may find widespread applications in regenerative medicine, drug screening, and potentially disease modeling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Unilateral anterior ischemic optic neuropathy

    DEFF Research Database (Denmark)

    Herbst, Kristina; Sander, Birgit; Lund-Andersen, Henrik

    2013-01-01

    of this study was to investigate the ipRGC mediated pupil response in patients with a unilateral non-arteritic anterior ischemic optic neuropathy (NAION). Consensual pupil responses during and after exposure to continuous 20 s blue (470 nm) or red (660 nm) light of high intensity (300 cd/m(2)) were recorded...

  19. [Ischemic stroke in young women

    NARCIS (Netherlands)

    Ekker, M.S.; Wermer, M.J.; Riksen, N.P.; Klijn, C.J.; Leeuw, F.E. de

    2016-01-01

    - In virtually all age groups, the incidence of ischemic stroke is higher in men. However, in women aged between 25-49 years the prevalence is higher than in men. Female-specific risk factors and disorders may explain this peak.- Pregnancy and the post-partum period are associated with physiological

  20. Diabetes and ischemic heart disease

    DEFF Research Database (Denmark)

    Bergmann, Natasha; Ballegaard, Søren; Holmager, Pernille

    2014-01-01

    The aim of this study was to test i) whether patients having diabetes and ischemic heart disease (IHD), i.e., patients suffering from two chronic diseases, demonstrate a higher degree of chronic stress when compared with patients suffering from IHD alone, and ii) whether suffering from the two...

  1. Olanzapine-induced ischemic colitis

    Directory of Open Access Journals (Sweden)

    Esteban Sáez-González

    Full Text Available Background: Ischemic colitis (IC is an uncommon adverse event associated with antipsychotic agents, more commonly found with phenothiazine drugs and atypical neuroleptics such as clozapine. The risk of developing ischemic colitis increases when anticholinergic drugs are associated. Case report: We report the case of a 38-year-old woman with a history of schizoaffective disorder who had been on chronic quetiapine for 3 years, and presented to the ER because of diarrhea for 5 days. Four months previously, olanzapine had been added to her psychiatric drug regimen. Physical examination revealed abdominal distension with abdominal tympanic sounds and tenderness. Emergency laboratory tests were notable for increased acute phase reagents. Tomography revealed a concentric thickening of the colonic wall in the transverse, descending and sigmoid segments, with no signs of intestinal perforation. Colonoscopy demonstrated severe mucosal involvement from the sigmoid to the hepatic flexure, with ulcerations and fibrinoid exudate. Biopsies confirmed the diagnosis of ischemic colitis. The only relevant finding in her history was the newly added drug to her baseline regimen. An adverse effect was suspected because of its anticholinergic action at the intestinal level, and the drug was withdrawn. After 6 months of follow-up clinical, laboratory and endoscopic recovery was achieved. Discussion: Antipsychotic medication should be considered as a potential cause of ischemic colitis, particularly atypical antipsychotics such as clozapine and olanzapine; despite being uncommon, this adverse event may result in high morbidity and mortality.

  2. The minimally tuned minimal supersymmetric standard model

    International Nuclear Information System (INIS)

    Essig, Rouven; Fortin, Jean-Francois

    2008-01-01

    The regions in the Minimal Supersymmetric Standard Model with the minimal amount of fine-tuning of electroweak symmetry breaking are presented for general messenger scale. No a priori relations among the soft supersymmetry breaking parameters are assumed and fine-tuning is minimized with respect to all the important parameters which affect electroweak symmetry breaking. The superpartner spectra in the minimally tuned region of parameter space are quite distinctive with large stop mixing at the low scale and negative squark soft masses at the high scale. The minimal amount of tuning increases enormously for a Higgs mass beyond roughly 120 GeV

  3. Left ventricular dysfunction in ischemic heart disease: fundamental importance of the fibrous matrix.

    Science.gov (United States)

    Swan, H J

    1994-05-01

    The contractile function of the myocardium is coordinated by a fibrous matrix of exquisite organization and complexity. In the normal heart, and apparently in physiological hypertrophy, this matrix is submicroscopic. In pathological states changes are frequent, and usually progressive. Thickening of the many elements of the fine structure is due to an increased synthesis of Type I collagen, This change, which affects the myocardium in a global manner, can be observed by light microscopy using special techniques. Perivascular fibrosis, with an increase in vascular smooth muscle, is accompanied by development of fibrous septa, with a decrease in diastolic compliance. These structural changes are believed to be due to increased activation of the renin-angiotensin-aldosterone system, and to be independent of the processes of myocyte hypertrophy. Reparative or replacement fibrosis is a separate process by means of which small and large areas of necrosis heal, with the development of coarse collagen structures, which lack a specific organizational pattern. Regarding ischemic heart disease, an increase in tissue collagenase is found in experimental myocardial "stunning" and in the very early phase of acute infarction. Absence of elements of the fibrous matrix allow for myocyte slippage, and--if the affected area is large--cardiac dilatation. If, subsequently, the necrosis becomes transmural, there is further disturbance of collagen due to both mechanical strain and continued autolysis, During healing collagen synthesis increases greatly to allow for reparative scarring in the available tissue matrix. In cases of infarction with moderate or severe initial dilatation, pathological hypertrophy of the spared myocardium is progressive, accounting for late heart failure and poor survival.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. MRI in the diagnosis of non-compacted ventricular Myocardium (NCVM) compared to echocardiography

    International Nuclear Information System (INIS)

    Weiss, F.; Habermann, C.R.; Sievers, J.; Weil, J.; Adam, G.; Lilje, C.; Razek, W.

    2003-01-01

    Purpose: To report the detection of con-compacted ventricular myocardium (NVCM) with MRI compared to echocardiography in 8 patients. Material and methods: Non-compaction of the ventricular myocardium is a congenital disorder characterized by an altered structure of the myocardial wall resulting from an intrauterine arrest in endomyocardial embryogenesis. The morphological findings consist of a prominent meshwork of multiple myocardial trabeculations and deep intertrabecular recesses, communicating with the left ventricular cavity. 8 consecutive patients (mean age 7.3 years) with clinical and echocardiographic signs of NCVM were examined by MRI (1.5 T, Vision, Siemens) in short axis and 2- and 4-chamber views, using T 1 -weighted TSE and Cine-GRE in 6 patients and true FISP sequences in 2 patients. MRI and echocardiography were evaluated for visibility, signs of NCVM and involvement of myocardial wall segments. Thickness was measured for non-compacted and compacted myocardium and the non-compacted to compacted (N/C) ratio calculated. Results: MRI diagnosed 6 of 8 patients of having NCVM. Myocardial thickness as measured by echocardiography and MRI showed a good correlation in compacted myocardium (r = 0.82) and no correlation in non-compacted myocardium (r = 0.4). In 2 cases, non-compacted myocardium was detected, but echocardiography did not reach the N/C ratio > 2 as required to diagnose NCVM in accordance with the criteria found in the literature. Both patients were also misdiagnosed by MRI performed with Cine-GRE. MRI reached a N/C ratio > 2 in only three patients. Newer TruFisp sequences showed no definite advantages. Extent of non-compaction could be visualized correctly with MRI. (orig.) [de

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

    International Nuclear Information System (INIS)

    Pitt, B.; Strauss, H.W.

    1976-01-01

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

  6. In vivo effect of the D-(-) isomer or natural form of 3-hydroxybutyrate on initial release of lactate dehydrogenase from the acutely ischaemic myocardium.

    Science.gov (United States)

    Lammerant, J; Huynh-Thu, T; Kolanowski, J

    1986-07-01

    D-(-)-3-hydroxybutyrate, the isomer found in the circulation and in the urine of diabetic patients, generally is believed to be the physiologically important form of 3-hydroxybutyrate [10]. Little is known concerning the effects of an elevated plasma level of the D-(-) isomer of 3-hydroxybutyrate upon the acutely ischaemic heart. Using anaesthetized intact dogs with a balloon catheter inserted into the proximal part of the left anterior descending coronary artery (LAD), we have recently demonstrated that a 1 mM ketonaemia induced with the arginine salt of D-(-)-3-hydroxybutyric acid reduces the uptake of non-esterified fatty acids (NEFA) in the myocardial area distal to the inflated balloon [4]. The question arises as to whether the concomitant increase in ketone uptake in this area could be detrimental to the acutely ischaemic myocardium. Indeed, a previous study on isolated coronary ligated hearts from normal rats has shown that the rate of release of lactate dehydrogenase (LDH) during the first 90 min of ischaemia can be enhanced by replacing glucose (11 mM) in the perfusion fluid with either albumin-bound palmitate (0.9 mM) or sodium DL-3-hydroxybutyrate (10 mM) as the sole energy substrate [11]. This would suggest that the ketone might be as deleterious as its metabolic precursors for membrane integrity in the acutely ischaemic myocardium. In the present report, we examine the effect of arginine D-(-)-3-hydroxybutyrate on LDH release from ischaemic myocardium in our in vivo preparation. The dogs were treated with lidocaine in order to minimize the frequency and, hence, the adverse metabolic effects of ectopic beats.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Free Radical Oxidation in Rat Myocardium after Maximum Permissible Hepatic Resection.

    Science.gov (United States)

    Ermolaev, P A; Khramykh, T P; Barskaya, L O

    2016-03-01

    Free radical oxidation in rat myocardial homogenate was studied by chemiluminescent assay during the early terms after maximum permissible liver resection. During this period, activation of free radical oxidation was biphasic. The critical terms characterized by dramatic intensification of free radical oxidation in the myocardium are the first hour and the first day after surgery. The period from 3 to 12 h after surgery, in which the indices of chemiluminescence decrease, can be tentatively termed as the period of "putative wellbeing". Normalization of the free radical oxidation processes in the myocardium occurred by day 7 after surgery.

  8. Statistical and fractal analysis of autofluorescent myocardium images in posthumous diagnostics of acute coronary insufficiency

    Science.gov (United States)

    Boichuk, T. M.; Bachinskiy, V. T.; Vanchuliak, O. Ya.; Minzer, O. P.; Garazdiuk, M.; Motrich, A. V.

    2014-08-01

    This research presents the results of investigation of laser polarization fluorescence of biological layers (histological sections of the myocardium). The polarized structure of autofluorescence imaging layers of biological tissues was detected and investigated. Proposed the model of describing the formation of polarization inhomogeneous of autofluorescence imaging biological optically anisotropic layers. On this basis, analytically and experimentally tested to justify the method of laser polarimetry autofluorescent. Analyzed the effectiveness of this method in the postmortem diagnosis of infarction. The objective criteria (statistical moments) of differentiation of autofluorescent images of histological sections myocardium were defined. The operational characteristics (sensitivity, specificity, accuracy) of these technique were determined.

  9. Protection from ischemic heart injury by a vigilant heme oxygenase-1 plasmid system.

    Science.gov (United States)

    Tang, Yao Liang; Tang, Yi; Zhang, Y Clare; Qian, Keping; Shen, Leping; Phillips, M Ian

    2004-04-01

    Although human heme oxygenase-1 (hHO-1) could provide a useful approach for cellular protection in the ischemic heart, constitutive overexpression of hHO-1 may lead to unwanted side effects. To avoid this, we designed a hypoxia-regulated hHO-1 gene therapy system that can be switched on and off. This vigilant plasmid system is composed of myosin light chain-2v promoter and a gene switch that is based on an oxygen-dependent degradation domain from the hypoxia inducible factor-1-alpha. The vector can sense ischemia and switch on the hHO-1 gene system, specifically in the heart. In an in vivo experiment, the vigilant hHO-1 plasmid or saline was injected intramyocardially into myocardial infarction mice or sham operation mice. After gene transfer, expression of hHO-1 was only detected in the ischemic heart treated with vigilant hHO-1 plasmids. Masson trichrome staining showed significantly fewer fibrotic areas in vigilant hHO-1 plasmids-treated mice compared with saline control (43.0%+/-4.8% versus 62.5%+/-3.3%, PhHO-1 expression in peri-infarct border areas, concomitant with higher Bcl-2 levels and lower Bax, Bak, and caspase 3 levels in the ischemic myocardium compared with saline control. By use of a cardiac catheter, heart from vigilant hHO-1 plasmids-treated mice showed improved recovery of contractile and diastolic performance after myocardial infarction compared with saline control. This study documents the beneficial regulation and therapeutic potential of vigilant plasmid-mediated hHO-1 gene transfer. This novel gene transfer strategy can provide cardiac-specific protection from future repeated bouts of ischemic injury.

  10. The minimal non-minimal standard model

    International Nuclear Information System (INIS)

    Bij, J.J. van der

    2006-01-01

    In this Letter I discuss a class of extensions of the standard model that have a minimal number of possible parameters, but can in principle explain dark matter and inflation. It is pointed out that the so-called new minimal standard model contains a large number of parameters that can be put to zero, without affecting the renormalizability of the model. With the extra restrictions one might call it the minimal (new) non-minimal standard model (MNMSM). A few hidden discrete variables are present. It is argued that the inflaton should be higher-dimensional. Experimental consequences for the LHC and the ILC are discussed

  11. Review of the emerging role of optical polarimetry in characterization of pathological myocardium.

    Science.gov (United States)

    Ahmad, Iftikhar

    2017-10-01

    Myocardial infarction (MI), a cause of significant morbidity and mortality, is typically followed by microstructural alterations where the necrotic myocardium is steadily replaced with a collagen scar. Engineered remodeling of the fibrotic scar via stem cell regeneration has been shown to improve/restore the myocardium function after MI. Nevertheless, the heterogeneous nature of the scar patch may impair the myocardial electrical integrity, leading to the formation of arrhythmogenesis. Radiofrequency ablation (RFA) offers an effective treatment for focal arrhythmias where local heating generated via electric current at specific spots in the myocardium ablate the arrhythmogenic foci. Characterization of these myocardial pathologies (i.e., infarcted, stem cell regenerated, and RFA-ablated myocardial tissues) is of potential clinical importance. Optical polarimetry, the use of light to map and characterize the polarization signatures of a sample, has emerged as a powerful imaging tool for structural characterization of myocardial tissues, exploiting the underlying highly fibrous tissue nature. This study aims to review the recent progress in optical polarimetry pertaining to the characterization of myocardial pathologies while describing the underlying biological rationales that give rise to the optical imaging contrast in various pathologies of the myocardium. Future possibilities of and challenges to optical polarimetry in cardiac imaging clinics are also discussed. (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  12. Pitx2 confers left morphological, molecular, and functional identity to the sinus venosus myocardium

    Czech Academy of Sciences Publication Activity Database

    Ammirabile, G.; Tessari, A.; Pignataro, V.; Szumska, D.; Sardo, F.S.; Beneš Jr., Jiří; Balistreri, M.; Bhattacharya, S.; Sedmera, David; Campione, M.

    2012-01-01

    Roč. 93, č. 2 (2012), s. 291-301 ISSN 0008-6363 R&D Projects: GA ČR(CZ) GA304/08/0615 Institutional research plan: CEZ:AV0Z50110509 Keywords : Pitx2 * sinus venosus myocardium * optical mapping * mouse cardiac development Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 5.940, year: 2012

  13. Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

    NARCIS (Netherlands)

    X.Y. Du (Xiaoyi); R.G. Schoemaker (Regien); E. Bos (Egbert); P.R. Saxena (Pramod Ranjan)

    1995-01-01

    textabstractIn the human isolated myocardium, acetylcholine (10−9 to 10−3 M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised

  14. Synchronous In Situ ATPase Activity, Mechanics, and Ca2+ Sensitivity of Human and Porcine Myocardium

    Czech Academy of Sciences Publication Activity Database

    Griffiths, P. J.; Isackson, H.; Pelc, Radek; Redwood, C.S.; Funari, S.S.; Watkins, H.; Ashley, C. C.

    2009-01-01

    Roč. 97, č. 9 (2009), s. 2503-2512 ISSN 0006-3495 R&D Projects: GA MŠk(CZ) LC06063 Grant - others:EC(XE) RII3-CT-2004-506008 Institutional research plan: CEZ:AV0Z50110509 Keywords : myocardium * actomyosin- ATPase * synchrotron-radiation Subject RIV: ED - Physiology Impact factor: 4.390, year: 2009

  15. Distribution and function of sodium channel subtypes in human atrial myocardium

    NARCIS (Netherlands)

    Kaufmann, Susann G.; Westenbroek, Ruth E.; Maass, Alexander H.; Lange, Volkmar; Renner, Andre; Wischmeyer, Erhard; Bonz, Andreas; Muck, Jenny; Ertl, Georg; Catterall, William A.; Scheuer, Todd; Maier, Sebastian K. G.

    Voltage-gated sodium channels composed of a pore-forming alpha subunit and auxiliary beta subunits are responsible for the upstroke of the action potential in cardiac muscle. However, their localization and expression patterns in human myocardium have not yet been clearly defined. We used

  16. Sensitization of the Guinea Pig Myocardium through the Mucous Membrane of the Digestive Tract,

    Science.gov (United States)

    Under certain conditions, sessile antibodies can be bound by the guinea - pig myocardium that had been sensitized by direct introduction of the allergen into the stomach. This is confirmed by the positive anaphylactic reaction in the isolated heart of animals treated in this manner, which reaction manifests itself in a modified heart rate when the isolated heart is challenged by the sensitizing allergen.

  17. Defined Engineered Human Myocardium with Advanced Maturation for Applications in Heart Failure Modelling and Repair

    Science.gov (United States)

    Tiburcy, Malte; Hudson, James E.; Balfanz, Paul; Schlick, Susanne; Meyer, Tim; Liao, Mei-Ling Chang; Levent, Elif; Raad, Farah; Zeidler, Sebastian; Wingender, Edgar; Riegler, Johannes; Wang, Mouer; Gold, Joseph D.; Kehat, Izhak; Wettwer, Erich; Ravens, Ursula; Dierickx, Pieterjan; van Laake, Linda W.; Goumans, Marie Jose; Khadjeh, Sara; Toischer, Karl; Hasenfuss, Gerd; Couture, Larry A.; Unger, Andreas; Linke, Wolfgang A.; Araki, Toshiyuki; Neel, Benjamin; Keller, Gordon; Gepstein, Lior; Wu, Joseph C.; Zimmermann, Wolfram-Hubertus

    2017-01-01

    Background Advancing structural and functional maturation of stem cell-derived cardiomyocytes remains a key challenge for applications in disease modelling, drug screening, and heart repair. Here, we sought to advance cardiomyocyte maturation in engineered human myocardium (EHM) towards an adult phenotype under defined conditions. Methods We systematically investigated cell composition, matrix and media conditions to generate EHM from embryonic and induced pluripotent stem cell-derived cardiomyocytes and fibroblasts with organotypic functionality under serum-free conditions. We employed morphological, functional, and transcriptome analyses to benchmark maturation of EHM. Results EHM demonstrated important structural and functional properties of postnatal myocardium, including: (1) rod-shaped cardiomyocytes with M-bands assembled as a functional syncytium; (2) systolic twitch forces at a similar level as observed in bona fide postnatal myocardium; (3) a positive force-frequency-response; (4) inotropic responses to β-adrenergic stimulation mediated via canonical β1- and β2-adrenoceptor signaling pathways; and (5) evidence for advanced molecular maturation by transcriptome profiling. EHM responded to chronic catecholamine toxicity with contractile dysfunction, cardiomyocyte hypertrophy, cardiomyocyte death, and NT-proBNP release; all are classical hallmarks of heart failure. Additionally, we demonstrate scalability of EHM according to anticipated clinical demands for cardiac repair. Conclusions We provide proof-of-concept for a universally applicable technology for the engineering of macro-scale human myocardium for disease modelling and heart repair from embryonic and induced pluripotent stem cell-derived cardiomyocytes under defined, serum-free conditions. PMID:28167635

  18. Defined Engineered Human Myocardium With Advanced Maturation for Applications in Heart Failure Modeling and Repair.

    Science.gov (United States)

    Tiburcy, Malte; Hudson, James E; Balfanz, Paul; Schlick, Susanne; Meyer, Tim; Chang Liao, Mei-Ling; Levent, Elif; Raad, Farah; Zeidler, Sebastian; Wingender, Edgar; Riegler, Johannes; Wang, Mouer; Gold, Joseph D; Kehat, Izhak; Wettwer, Erich; Ravens, Ursula; Dierickx, Pieterjan; van Laake, Linda W; Goumans, Marie Jose; Khadjeh, Sara; Toischer, Karl; Hasenfuss, Gerd; Couture, Larry A; Unger, Andreas; Linke, Wolfgang A; Araki, Toshiyuki; Neel, Benjamin; Keller, Gordon; Gepstein, Lior; Wu, Joseph C; Zimmermann, Wolfram-Hubertus

    2017-05-09

    Advancing structural and functional maturation of stem cell-derived cardiomyocytes remains a key challenge for applications in disease modeling, drug screening, and heart repair. Here, we sought to advance cardiomyocyte maturation in engineered human myocardium (EHM) toward an adult phenotype under defined conditions. We systematically investigated cell composition, matrix, and media conditions to generate EHM from embryonic and induced pluripotent stem cell-derived cardiomyocytes and fibroblasts with organotypic functionality under serum-free conditions. We used morphological, functional, and transcriptome analyses to benchmark maturation of EHM. EHM demonstrated important structural and functional properties of postnatal myocardium, including: (1) rod-shaped cardiomyocytes with M bands assembled as a functional syncytium; (2) systolic twitch forces at a similar level as observed in bona fide postnatal myocardium; (3) a positive force-frequency response; (4) inotropic responses to β-adrenergic stimulation mediated via canonical β 1 - and β 2 -adrenoceptor signaling pathways; and (5) evidence for advanced molecular maturation by transcriptome profiling. EHM responded to chronic catecholamine toxicity with contractile dysfunction, cardiomyocyte hypertrophy, cardiomyocyte death, and N-terminal pro B-type natriuretic peptide release; all are classical hallmarks of heart failure. In addition, we demonstrate the scalability of EHM according to anticipated clinical demands for cardiac repair. We provide proof-of-concept for a universally applicable technology for the engineering of macroscale human myocardium for disease modeling and heart repair from embryonic and induced pluripotent stem cell-derived cardiomyocytes under defined, serum-free conditions. © 2017 American Heart Association, Inc.

  19. Metabolic reserve in normal myocardium assessed by positron emission tomography with C-11 palmitate

    International Nuclear Information System (INIS)

    Tamaki, Nagara; Kawamoto, Masahide; Takahashi, Norio; Yonekura, Yoshiharu; Magata, Yasuhiro; Nohara, Ryuji; Kambara, Hirofumi; Kawai, Chuichi; Konishi, Junji

    1991-01-01

    Positron emission tomography (PET) with C-11 palmitate has been used in estimating the myocardial utilization of free fatty acid. To assess the metabolic reserve in normal subjects, a PET study was performed at control and during dobutamine infusion at 2 hour intervals in 5 normal subjects. Following monoexponential curve fitting of the time activity curve of the myocardium, the clearance half time (min) and residual fraction (%) were calculated as indices of β-oxydation of free fatty acid. A significant increase in the heart rate and systolic blood pressure were observed during dobutamine infusion (65±5 vs 100±29 bpm, p<0.05 and 119±12 vs 144±16 mmHg, p<0.01, respectively). The clearance half-time and the residual fraction were significantly decreased (23.4±2.6 vs 15.8±2.3 min and 67.0±2.5 vs 58.6±4.0%, p<0.05, each). When the left ventricular myocardium was divided into 4 segments, these indices were similar at control and uniformly decreased without regional differences during dobutamine infusion. These data suggest that β-oxydation of free fatty acid may be uniformly increased in the left ventricular myocardium in relation to the increase in cardiac work in normal subjects. PET with C-11 palmitate at control and during dobutamine infusion is considered to be promising in assessing metabolic reserve in the myocardium. (author)

  20. Radiolabeled Rhein as Small-Molecule Necrosis Avid Agents for Imaging of Necrotic Myocardium.

    Science.gov (United States)

    Luo, Qi; Jin, Qiaomei; Su, Chang; Zhang, Dongjian; Jiang, Cuihua; Fish, Anne Folta; Feng, Yuanbo; Ni, Yicheng; Zhang, Jian; Yin, Zhiqi

    2017-01-17

    A rapid and accurate identification of necrotic myocardium is of great importance for diagnosis, risk stratification, clinical decision-making, and prognosis evaluation of myocardial infarction. Here, we explored technetium-99m labeled rhein derivatives for rapid imaging of the necrotic myocardium. Three hydrazinonicotinic acid-linker-rhein (HYNIC-linker-rhein) derivatives were synthesized, and then, these synthetic compounds were labeled with technetium-99m using ethylenediaminediacetic acid (EDDA) and tricine as coligands [ 99m Tc(EDDA)-HYNIC-linker-rhein]. The necrosis avidity of the three 99m Tc-labeled rhein derivatives was tested in a mouse model of ethanol-induced muscular necrosis by gamma counting, histochemical staining, and autoradiography. A lead tracer for visualization of necrotic myocardium was assessed by single photon emission computed tomography/computed tomography (SPECT/CT) imaging in a rat model with reperfused myocardial infarction. The necrosis avidity mechanism of the tracer was explored by DNA binding studies in vitro and blocking experiments in vivo. Results showed that the uptake in necrotic muscles of the three 99m Tc-compounds was higher than that in viable muscles (P EDDA)-HYNIC-ethylenediamine-rhein [ 99m Tc(EDDA)-HYNIC-2C-rhein] displayed the best distribution profiles for imaging. The necrotic myocardium lesions were clearly visualized by SPECT/CT using 99m Tc(EDDA)-HYNIC-2C-rhein at 1 h after injection. The necrotic-to-viable myocardium and necrotic myocardium-to-blood uptake ratios of 99m Tc(EDDA)-HYNIC-2C-rhein were 4.79 and 3.02 at 1 h after injection. DNA binding studies suggested HYNIC-linker-rhein bound to DNA through intercalation. The uptake of 99m Tc(EDDA)-HYNIC-2C-rhein in necrotic muscle was significantly blocked by excessive unlabeled rhein, with 77.61% decline at 1 h after coinjection. These findings suggested 99m Tc(EDDA)-HYNIC-2C-rhein emerged as a "hot spot" imaging probe that has a potential for rapid imaging of

  1. Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes

    OpenAIRE

    Perna, Robert; Temple, Jessica

    2015-01-01

    Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n = 172) or hemorrhagic stroke (n = 112) within the past six months and were involved in a postacute neurorehabilitation program....

  2. Comparative study between MRI and echocardiography in noncompaction of ventricular myocardium

    International Nuclear Information System (INIS)

    Sun Ziyan; Xia Liming; Wang Chengyuan; Rao Jingjing; Shenyu Weihui

    2007-01-01

    Objective: To investigate the MRI and echocardiography manifestations of noncompaction of ventricular myocardium(NVM) and assess the role of MR1 in the diagnosis of NVM by comparing it with echocardiography. Methods: Fourteen cases of NVM diagnosed by echocardiography were examined with MRI, including scanning of black-blood sequences, double inversion recovery fast spin echo (DIBFSE) and triple inversion recovery fast spin echo (TIRFSE), and white blood sequence: fast imaging employ steady state acquisition (FIESTA). Scanning plane includes short axis view, four-chamber view and long axis view. Results: Both MRI and echocardiography displayed involvement of left ventricles in thirteen cases and involvement of double ventricles in one case. Apexes of heart and the intermedius are commonly affected. MRI showed 54 segments and echocardiography showed 53 segments affected, and there is no significant difference between the capability of MRI and echocardiography (P=1,000). The affected myocardium consisted of two layers: subendocardial noncompacted myocardium and epicardial compacted myocardium, and the ratio measurement of N/C by MRI was 3.37±0.89 and it was 3.19±0.82 by echocardiography. Noncompacted myocardium was characterized by prominent and excessive myocardial trabeculations and deep intratrabecular recesses, in which the blood flow was communicated with the ventricle. One case was complicated with ventricular aneurysm, and coronary arteriography was performed with unremarkable findings. One case underwent heart transplantation because of progressive heart failure, Gross findings demonstrated prominent muscular' trabeculations with deep intratrabecular recesses, which coincided well with MRI findings. Conclusion: The MRI manifestation of NVM is characteristic, and MRI with multiple series and planes is helpful in the diagnose of NVM. Compared with echocardiography, MRI could display the pathological cardiac muscle more clearly, because of its high soft

  3. Decline of Phosphotransfer and Substrate Supply Metabolic Circuits Hinders ATP Cycling in Aging Myocardium.

    Directory of Open Access Journals (Sweden)

    Emirhan Nemutlu

    Full Text Available Integration of mitochondria with cytosolic ATP-consuming/ATP-sensing and substrate supply processes is critical for muscle bioenergetics and electrical activity. Whether age-dependent muscle weakness and increased electrical instability depends on perturbations in cellular energetic circuits is unknown. To define energetic remodeling of aged atrial myocardium we tracked dynamics of ATP synthesis-utilization, substrate supply, and phosphotransfer circuits through adenylate kinase (AK, creatine kinase (CK, and glycolytic/glycogenolytic pathways using 18O stable isotope-based phosphometabolomic technology. Samples of intact atrial myocardium from adult and aged rats were subjected to 18O-labeling procedure at resting basal state, and analyzed using the 18O-assisted HPLC-GC/MS technique. Characteristics for aging atria were lower inorganic phosphate Pi[18O], γ-ATP[18O], β-ADP[18O], and creatine phosphate CrP[18O] 18O-labeling rates indicating diminished ATP utilization-synthesis and AK and CK phosphotransfer fluxes. Shift in dynamics of glycolytic phosphotransfer was reflected in the diminished G6P[18O] turnover with relatively constant glycogenolytic flux or G1P[18O] 18O-labeling. Labeling of G3P[18O], an indicator of G3P-shuttle activity and substrate supply to mitochondria, was depressed in aged myocardium. Aged atrial myocardium displayed reduced incorporation of 18O into second (18O2, third (18O3, and fourth (18O4 positions of Pi[18O] and a lower Pi[18O]/γ-ATP[18 O]-labeling ratio, indicating delayed energetic communication and ATP cycling between mitochondria and cellular ATPases. Adrenergic stress alleviated diminished CK flux, AK catalyzed β-ATP turnover and energetic communication in aging atria. Thus, 18O-assisted phosphometabolomics uncovered simultaneous phosphotransfer through AK, CK, and glycolytic pathways and G3P substrate shuttle deficits hindering energetic communication and ATP cycling, which may underlie energetic

  4. Selective blockade of protein kinase B protects the rat and human myocardium against ischaemic injury

    Science.gov (United States)

    Linares-Palomino, José; Husainy, Muhammad A; Lai, Vien K; Dickenson, John M; Galiñanes, Manuel

    2010-01-01

    Protein kinase B (PKB/Akt) plays a critical role in cell survival but the investigation of its involvement has been limited by the lack of specific pharmacological agents. In this study, using novel PKB inhibitors (VIII and XI), we investigated the role of PKB in cardioprotection of the rat and human myocardium, the location of PKB in relation to mitoKATP channels and p38 mitogen-activated protein kinase (p38 MAPK), and whether the manipulation of PKB can overcome the unresponsiveness to protection of the diabetic myocardium. Myocardial slices from rat left ventricle and from the right atrial appendage of patients undergoing elective cardiac surgery were subjected to 90 min ischaemia/120 min reoxygenation at 37°C. Tissue injury was assessed by creatine kinase (CK) released and determination of cell necrosis and apoptosis. The results showed that blockade of PKB activity caused significant reduction of CK release and cell death, a benefit that was as potent as ischaemic preconditioning and could be reproduced by blockade of phosphatidylinositol 3-kinase (PI-3K) with wortmannin and LY 294002. The protection was time dependent with maximal benefit seen when PKB and PI-3K were inhibited before ischaemia or during both ischaemia and reoxygenation. In addition, it was revealed that PKB is located downstream of mitoKATP channels but upstream of p38 MAPK. PKB inhibition induced a similar degree of protection in the human and rat myocardium and, importantly, it reversed the unresponsiveness to protection of the diabetic myocardium. In conclusion, inhibition of PKB plays a critical role in protection of the mammalian myocardium and may represent a clinical target for the reduction of ischaemic injury. PMID:20403980

  5. Subacute ghrelin administration inhibits apoptosis and improves ultrastructural abnormalities in remote myocardium post-myocardial infarction.

    Science.gov (United States)

    Eid, Refaat A; Zaki, Mohamed Samir Ahmed; Al-Shraim, Mubarak; Eleawa, Samy M; El-Kott, Attalla Farag; Al-Hashem, Fahaid H; Eldeen, Muhammad Alaa; Ibrahim, Hoja; Aldera, Hussain; Alkhateeb, Mahmoud A

    2018-05-01

    This study investigated the effect of ghrelin on cardiomyocytes function, apoptosis and ultra-structural alterations of remote myocardium of the left ventricle (LV) of rats, 21 days post myocardial infarction (MI). Rats were divided into 4 groups as a control, a sham-operated rats, a sham-operated+ghrelin, an MI + vehicle and an MI + ghrelin-treated rats. MI was induced by LAD ligation and then rats were recievd a concomitant doe of either normal saline as a vehicle or treated with ghrelin (100 μg/kg S.C., 2x/day) for 21 consecutive days. Ghrelin enhanced myocardial contractility in control rats and reversed the decreases in myocardial contractility and the increases in the serum levels of CK-MB and LDH in MI-induced rats. Additionally, it inhibited the increases in levels of Bax and cleaved caspase 3 and increased those for Bcl-2 in the remote myocardium of rat's LV, post-MI. At ultra-structural level, while ghrelin has no adverse effects on LV myocardium obtained from control or sham-treated rats, ghrelin post-administration to MI-induced rats reduced vascular formation, restored normal microfilaments appearance and organization, preserved mitochondria structure, and prevented mitochondrial swelling, collagen deposition and number of ghost bodies in the remote areas of their LV. Concomitantly, in remote myocardium of MI-induced rats, ghrelin enhanced endoplasmic reticulum intracellular organelles count, decreased number of atrophied nuclei and phagocytes, diminished the irregularity in the nuclear membranes and inhibited chromatin condensation. In conclusion, in addition to the physiological, biochemical and molecular evidence provided, this is the first study that confirms the anti-apoptotic effect of ghrelin in the remote myocardium of the LV during late MI at the level of ultra-structural changes. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  6. Cryopreserved Off-the-Shelf Allogeneic Adipose-Derived Stromal Cells for Therapy in Patients with Ischemic Heart Disease and Heart Failure-A Safety Study

    DEFF Research Database (Denmark)

    Kastrup, Jens; Haack-Sørensen, Mandana; Juhl, Morten

    2017-01-01

    and ischemic heart failure (IHF). Batches of CSCC_ASC were isolated from three healthy donors by liposuction from abdominal adipose tissue. Adipose mesenchymal stromal cells were culture expanded in bioreactors without the use of animal constituents, cryopreserved, and stored in vials in nitrogen dry......The present first-in-human clinical trial evaluated the safety and feasibility of a newly developed and cryopreserved Cardiology Stem Cell Centre adipose-derived stromal cell (CSCC_ASC) product from healthy donors for intramyocardial injection in ten patients with ischemic heart disease......-storage containers until use. Direct injection of CSCC_ASC into the myocardium did not cause any complications or serious adverse events related to either treatment or cell administration in a 6-month follow-up period. Four out of ten heart failure patients developed donor-specific de novo human leukocyte antigen...

  7. Pioglitazone after Ischemic Stroke or Transient Ischemic Attack.

    Science.gov (United States)

    Kernan, Walter N; Viscoli, Catherine M; Furie, Karen L; Young, Lawrence H; Inzucchi, Silvio E; Gorman, Mark; Guarino, Peter D; Lovejoy, Anne M; Peduzzi, Peter N; Conwit, Robin; Brass, Lawrence M; Schwartz, Gregory G; Adams, Harold P; Berger, Leo; Carolei, Antonio; Clark, Wayne; Coull, Bruce; Ford, Gary A; Kleindorfer, Dawn; O'Leary, John R; Parsons, Mark W; Ringleb, Peter; Sen, Souvik; Spence, J David; Tanne, David; Wang, David; Winder, Toni R

    2016-04-07

    Patients with ischemic stroke or transient ischemic attack (TIA) are at increased risk for future cardiovascular events despite current preventive therapies. The identification of insulin resistance as a risk factor for stroke and myocardial infarction raised the possibility that pioglitazone, which improves insulin sensitivity, might benefit patients with cerebrovascular disease. In this multicenter, double-blind trial, we randomly assigned 3876 patients who had had a recent ischemic stroke or TIA to receive either pioglitazone (target dose, 45 mg daily) or placebo. Eligible patients did not have diabetes but were found to have insulin resistance on the basis of a score of more than 3.0 on the homeostasis model assessment of insulin resistance (HOMA-IR) index. The primary outcome was fatal or nonfatal stroke or myocardial infarction. By 4.8 years, a primary outcome had occurred in 175 of 1939 patients (9.0%) in the pioglitazone group and in 228 of 1937 (11.8%) in the placebo group (hazard ratio in the pioglitazone group, 0.76; 95% confidence interval [CI], 0.62 to 0.93; P=0.007). Diabetes developed in 73 patients (3.8%) and 149 patients (7.7%), respectively (hazard ratio, 0.48; 95% CI, 0.33 to 0.69; Pischemic stroke or TIA, the risk of stroke or myocardial infarction was lower among patients who received pioglitazone than among those who received placebo. Pioglitazone was also associated with a lower risk of diabetes but with higher risks of weight gain, edema, and fracture. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT00091949.).

  8. Critical review-current status of Tl-201 myocardial scintigraphy in patients with ischemic heart disease

    International Nuclear Information System (INIS)

    Kanemoto, Nariaki; Hoer, G.

    1982-01-01

    Thallium-201 myocardial scintigraphy (TMS) is the most important, accurate and noninvasive diagnostic tool for the detection of regional myocardial perfusion. This agent is a potassium analog and the biologic half life in normal myocardium is 4 hours. Therefore, serial imaging after a single dose of Tl-201 at the peak of the exercise makes differential diagnosis possible between stress induced ischemia (transient perfusion defect with redistribution) and myocardial fibrosis or scar (permanent defect). The reproducibility is around 90%. The overall sensitivity in 4,094 patients reviewed from the literature was 83% with a specificity of 87%. The accuracy of TMS for the diagnosis of ischemic heart disease was 85%. Sensitivity increases in the order of visual (83%), computer analysis of standard scintigraphy (91%), and computer analysis of pinhole tomography (96%), but there is no significant difference in specificity among them. Also, sensitivity increases in the order of single (73%), double (83%) and triple (90%) vessel d isease. However, TMS does not indicate the correct number of vessels involved. In this paper, we discuss the current status of use and limitations of TMS in the diagnosis of ischemic heart disease. (author)

  9. Peripheral Mechanisms of Ischemic Myalgia

    Directory of Open Access Journals (Sweden)

    Luis F. Queme

    2017-12-01

    Full Text Available Musculoskeletal pain due to ischemia is present in a variety of clinical conditions including peripheral vascular disease (PVD, sickle cell disease (SCD, complex regional pain syndrome (CRPS, and even fibromyalgia (FM. The clinical features associated with deep tissue ischemia are unique because although the subjective description of pain is common to other forms of myalgia, patients with ischemic muscle pain often respond poorly to conventional analgesic therapies. Moreover, these patients also display increased cardiovascular responses to muscle contraction, which often leads to exercise intolerance or exacerbation of underlying cardiovascular conditions. This suggests that the mechanisms of myalgia development and the role of altered cardiovascular function under conditions of ischemia may be distinct compared to other injuries/diseases of the muscles. It is widely accepted that group III and IV muscle afferents play an important role in the development of pain due to ischemia. These same muscle afferents also form the sensory component of the exercise pressor reflex (EPR, which is the increase in heart rate and blood pressure (BP experienced after muscle contraction. Studies suggest that afferent sensitization after ischemia depends on interactions between purinergic (P2X and P2Y receptors, transient receptor potential (TRP channels, and acid sensing ion channels (ASICs in individual populations of peripheral sensory neurons. Specific alterations in primary afferent function through these receptor mechanisms correlate with increased pain related behaviors and altered EPRs. Recent evidence suggests that factors within the muscles during ischemic conditions including upregulation of growth factors and cytokines, and microvascular changes may be linked to the overexpression of these different receptor molecules in the dorsal root ganglia (DRG that in turn modulate pain and sympathetic reflexes. In this review article, we will discuss the

  10. Fractal analysis of phasic laser images of the myocardium for the purpose of diagnostics of acute coronary insufficiency

    Science.gov (United States)

    Wanchuliak, O. Y.; Bachinskyi, V. T.

    2011-09-01

    In this work on the base of Mueller-matrix description of optical anisotropy, the possibility of monitoring of time changes of myocardium tissue birefringence, has been considered. The optical model of polycrystalline networks of myocardium is suggested. The results of investigating the interrelation between the values correlation (correlation area, asymmetry coefficient and autocorrelation function excess) and fractal (dispersion of logarithmic dependencies of power spectra) parameters are presented. They characterize the distributions of Mueller matrix elements in the points of laser images of myocardium histological sections. The criteria of differentiation of death coming reasons are determined.

  11. Sex Hormones and Ischemic Stroke

    DEFF Research Database (Denmark)

    Holmegard, Haya N; Nordestgaard, Børge G; Jensen, Gorm B

    2016-01-01

    CONTEXT AND OBJECTIVE: Whether endogenous sex hormones are associated with ischemic stroke (IS) is unclear. We tested the hypothesis that extreme concentrations of endogenous sex hormones are associated with risk of IS in the general population. DESIGN, SETTING, AND PARTICIPANTS: Adult men (n...... = 4615) and women (n = 4724) with measurements of endogenous sex hormones during the 1981-1983 examination of the Copenhagen City Heart Study, Denmark, were followed for up to 29 years for incident IS, with no loss to follow-up. Mediation analyses assessed whether risk of IS was mediated through...

  12. The Histological Effects of L-arginine on Ventricular Myocardium in Iron Treated Male Rats

    Directory of Open Access Journals (Sweden)

    M Sofiabadi

    2012-05-01

    Full Text Available

    Background and Objectives: Iron overload is detrimental for the body and can create damage to different body tissues, such as myocardium by producing oxidative stress. Therefore, the antioxidant factors can neutralize iron induced damages. According to available reports, L-arginine as a precursor nitric oxide production has antioxidant effects. This study was carried out to evaluate the histological effects of iron overload on ventricular muscle and preventive role of L-arginine in male rats.
    Methods: In this experiment, 40 male rats with weight range of 300-250g were divided at random into five equal groups including:1- Control, 2- Iron (10mg/kg, ip, 3- Iron(10mg/kg, ip+L-arginine (1mg/ml, po, 4- Iron (50mg/kg, ip and 5- Iron (50mg/kg,ip+L-arginine(1mg/ml,po. After treatment (6 weeks, the animals were anesthetized and the samples of left apical ventricular myocardium were taken out and morphological studies were done following fixation with 10% formalin and H&E staining. Microscopic parameters under study were cell swelling, vessel dilatation and hypercongestion, cell necrosis and tissue deformity. The type and severity of damage to the tissue were also noted. Data were analyzed using chi-square statistical procedure, and Pvalue≤0.05 were considered to be significant. 
    Results: The data showed moderate changes in the ventricular myocardium of group 2 that was significant in comparison to the control group (P<0.05. The ventricular myocardium of group 3 showed low changes and wasn't significant in comparison to control group (P=0.84. The ventricular myocardium of the group 4 showed severe changes in comparison to the control group (P<0.01. The low change showed in the ventricular myocardium of group 5 that wasn't significant in comparison to the control group.

    Conclusion: This study showed

  13. Effectiveness of home rehabilitation for ischemic stroke

    Directory of Open Access Journals (Sweden)

    Pakaratee Chaiyawat

    2009-08-01

    Full Text Available The objective of this study was to develop and examine the effectiveness of an individual home rehabilitation program for patients with ischemic stroke. This was a randomized controlled trial in 60 patients with recent middle cerebral artery infarction. After hospital discharge for acute stroke care, they were randomly assigned to receive either a home rehabilitation program for three months (intervention group or usual care (control group. We collected outcome data over three months after their discharge from the hospital. The Barthel Index (BI, the Modified Rankin Scale (MRS, the health-related quality-of-life index (EQ-5D, the Hospital Anxiety and Depression score (HADs, and the Thai Mental State Examination (TMSE were used to analyze the outcomes. In the intervention group, all outcomes were significantly better (p<0.05 than in the control group, except in the case of TMSE. A favorable outcome, which was defined as minimal or no disability as measured by BI (score 95-100, was achieved by 93.33% of patients in the intervention group, and 90% had favorable scores (0 or 1 on the MRS. This showed a benefit in reducing disability, with two being the number of patients considered as needed-to-treat (NNT (95% CI, 1.0-1.2. All dimensions of EQ-5D in the intervention group were significantly better for quality of life and generic health status than in the control group (p=0.001. Depression was found in one patient (3.33% in the intervention group and in two patients (6.67% in the control group. Dementia was found in three patients (10% in the intervention group and in four patients (13.33% in the control group. We concluded that an early home rehabilitation program for patients with ischemic stroke in the first three-month period provides significantly better outcomes in improving function, reducing disability, increasing quality of life, and reducing depression than a program of usual care does.

  14. 25-Hydroxyvitamin D and symptomatic ischemic stroke

    DEFF Research Database (Denmark)

    Brøndum-Jacobsen, Peter; Nordestgaard, Børge G; Schnohr, Peter

    2013-01-01

    City Heart Study. During 21 years of follow-up, 1,256 and 164 persons developed ischemic and hemorrhagic stroke, respectively. In a meta-analysis of ischemic stroke, we included 10 studies, 58,384 participants, and 2,644 events. RESULTS: Stepwise decreasing plasma 25-hydroxyvitamin D concentrations...

  15. Cerebral ischemic stroke: is gender important?

    Science.gov (United States)

    Gibson, Claire L

    2013-09-01

    Cerebral stroke continues to be a major cause of death and the leading cause of long-term disability in developed countries. Evidence reviewed here suggests that gender influences various aspects of the clinical spectrum of ischemic stroke, in terms of influencing how a patients present with ischemic stroke through to how they respond to treatment. In addition, this review focuses on discussing the various pathologic mechanisms of ischemic stroke that may differ according to gender and compares how intrinsic and hormonal mechanisms may account for such gender differences. All clinical trials to date investigating putative neuroprotective treatments for ischemic stroke have failed, and it may be that our understanding of the injury cascade initiated after ischemic injury is incomplete. Revealing aspects of the pathophysiological consequences of ischemic stroke that are gender specific may enable gender relevant and effective neuroprotective strategies to be identified. Thus, it is possible to conclude that gender does, in fact, have an important role in ischemic stroke and must be factored into experimental and clinical investigations of ischemic stroke.

  16. Molecular Mechanisms of Renal Ischemic Conditioning Strategies

    DEFF Research Database (Denmark)

    Kierulf-Lassen, Casper; Nieuwenhuijs-Moeke, Gertrude J; Krogstrup, Nicoline V

    2015-01-01

    summarizes research on the molecular mechanisms underlying both local and remote ischemic pre-, per- and postconditioning of the kidney. The different types of conditioning strategies in the kidney recruit similar powerful pro-survival mechanisms. Likewise, renal ischemic conditioning mobilizes many...

  17. Genetic variation in WRN and ischemic stroke

    DEFF Research Database (Denmark)

    Christoffersen, Mette; Frikke-Schmidt, Ruth; Nordestgaard, Børge G.

    2017-01-01

    trends for ischemic cerebrovascular disease (P = 0.06). In meta-analyses including 59,190 individuals in 5 studies, the hazard ratio for ischemic stroke for C1367R TT homozygotes versus CC/CT was 1.14 (1.04–1.25; P = 0.008). Conclusions This study suggests that common genetic variation in WRN......Background Werner syndrome, a premature genetic aging syndrome, shares many clinical features reminiscent of normal physiological aging, and ischemic vascular disease is a frequent cause of death. We tested the hypothesis that genetic variation in the WRN gene was associated with risk of ischemic...... vascular disease in the general population. Methods We included 58,284 participants from two general population cohorts, the Copenhagen City Heart Study (CCHS) and the Copenhagen General Population Study (CGPS). Of these, 6,312 developed ischemic vascular disease during follow-up. In the CCHS (n = 10...

  18. Regularity of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J; Kuster, Albrecht

    2010-01-01

    "Regularity of Minimal Surfaces" begins with a survey of minimal surfaces with free boundaries. Following this, the basic results concerning the boundary behaviour of minimal surfaces and H-surfaces with fixed or free boundaries are studied. In particular, the asymptotic expansions at interior and boundary branch points are derived, leading to general Gauss-Bonnet formulas. Furthermore, gradient estimates and asymptotic expansions for minimal surfaces with only piecewise smooth boundaries are obtained. One of the main features of free boundary value problems for minimal surfaces is t

  19. Olson method for locating and calculating the extent of transmural ischemic areas at risk of infarction.

    Science.gov (United States)

    Olson, Charles W; Wagner, Galen S; Terkelsen, Christian Juhl; Stickney, Ronald; Lim, Tobin; Pahlm, Olle; Estes, E Harvey

    2014-01-01

    The purpose of this study is to present a new and improved method for translating the electrocardiographic changes of acute myocardial ischemia into a display which reflects the location and extent of the ischemic area and the associated culprit coronary artery. This method could be automated to present a graphic image of the ischemic area in a manner understandable by all levels of caregivers; from emergency transport personnel to the consulting cardiologist. Current methods for the ECG diagnosis of ST elevated myocardial infarction (STEMI) are criteria driven, and complex, and beyond the interpretive capability of many caregivers. New methods are needed to accurately diagnose the presence of acute transmural myocardial ischemia in order to accelerate a patient's clinical "door to balloon time." The proposed new method could potentially provide the information needed to accomplish this objective. The new method improves the precision of diagnosis and quantification of ischemia by normalizing the ST segment inputs from the standard 12 lead ECG, transforming these into a three dimensional vector representation of the ischemia at the electrical center of the heart. The myocardial areas likely to be involved in this ischemia are separately analyzed to assess the probability that they contributed to this event. The source of the ischemia is revealed as a specific region of the heart, and the likely location of the associated culprit coronary artery. Seventy 12 lead ECGs from subjects with known single artery occlusion in one of the three main coronary arteries were selected to test this new method. Graphic plots of the distribution of ischemia as indicated by the method are consistent with the known occlusion. The analysis of the distribution of ischemic areas in the myocardium reveals that the relationships between leads with either ST elevation or ST depression, provide critical information improving the current method. Copyright © 2014 Elsevier Inc. All rights

  20. Swallowing disorders after ischemic stroke

    Directory of Open Access Journals (Sweden)

    Gabriela Camargo Remesso

    2011-10-01

    Full Text Available OBJECTIVE: To investigate occurrences of swallowing disorders after ischemic stroke. METHOD: This was a retrospective study on 596 medical files. The inclusion criterion was that the patients needed to have been hospitalized with a diagnosis of ischemic stroke; the exclusion criteria were the presence of associated cardiac problems and hospital stay already more than 14 days. RESULTS: 50.5% were men and 49.5% women; mean age 65.3 years (SD=±11.7 (p<0.001. Among the risk factors, 79.4% had hypertension, 36.7% had diabetes (p<0.001 and 42.7% were smokers. 13.3% of the patients died. Swallowing disorders occurred in 19.6%, among whom 91.5% had mild difficulty and 8.5% had severe difficulty. 87.1% had spontaneous recovery after a mean of 2.4 months. A lesion in the brainstem region occurred in 6.8% (p<0.001. CONCLUSION: Swallowing disorders occurred in almost 20% of the population and most of the difficulty in swallowing found was mild. The predictors for swallowing disorders were older age, diabetes mellitus and lesions in the brainstem region.

  1. Age-dependent changes in expression of alpha1-adrenergic receptors in rat myocardium

    International Nuclear Information System (INIS)

    Schaffer, W.; Williams, R.S.

    1986-01-01

    The expression of alpha 1 -adrenergic receptors within ventricular myocardium of rats ranging in age from 21 days of fetal life to 24 months after birth was measured from [ 125 I] 2-(β hydroxy phenyl) ethylaminomethyl tetralone binding isotherms. No difference was observed in binding affinity between any of the age groups studied. The number of alpha 1 -adrenergic receptors was found to be 60-120% higher in membranes from fetal or immature rats up to 25 days of age when compared with adult animals. The increased expression of alpha 1 -adrenergic receptors in the developing heart relative to that observed in adult heart is consistent with the hypothesis that alpha 1 -adrenergic receptor stimulation may modulate protein synthesis and growth in mammalian myocardium

  2. Distinction of salvaged and infarcted myocardium within the ischaemic area-at-risk with T2 mapping

    DEFF Research Database (Denmark)

    Hammer-Hansen, Sophia; Ugander, Martin; Hsu, Li-Yueh

    2014-01-01

    values from T2 maps and signal intensities on T2-weighted images were measured in the corresponding areas. RESULTS: At both imaging time points, the T2 of the salvaged myocardium was longer than of remote (66.0 ± 6.9 vs. 51.4 ± 3.5 ms, P ...AIM: Area-at-risk (AAR) measurements often rely on T2-weighted images, but subtle differences in T2 may be overlooked with this method. To determine the differences in oedema between salvaged and infarcted myocardium, we performed quantitative T2 mapping of the AAR. We also aimed to determine...... (14.7 ± 5.6 vs. 8.7 ± 5.1 ms, P = 0.02). CONCLUSIONS: T2 relaxation parameters are different in the infarcted and salvaged myocardium, and both are significantly longer than remote. Furthermore, the magnitude of increase in T2 was less in the salvaged myocardium after longer reperfusion, indicating...

  3. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    Energy Technology Data Exchange (ETDEWEB)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Mongillo, Marco; Khan, Muhammad T. [Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); Depre, Christophe [University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Cell Biology and Molecular Medicine, New Jersey, NJ (United States); University of Medicine and Dentistry New Jersey, Cardiovascular Research Institute, Department of Medicine, New Jersey, NJ (United States); Rimoldi, Ornella E. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom); New York Medical College, Cardiovascular Research Institute, Department of Medicine, Valhalla, NY (United States); Camici, Paolo G. [Imperial College, Hammersmith Hospital, National Heart and Lung Institute, London (United Kingdom); Imperial College, Hammersmith Hospital, Medical Research Council Clinical Sciences Centre, London (United Kingdom)

    2007-12-15

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([{sup 11}C]meta-hydroxy-ephedrine; HED) and {beta}-adrenoceptor ({beta}-AR) density ([{sup 11}C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V{sub d}) of HED in HM (47.95{+-}28.05 ml/g) and infarcted myocardium (42.69{+-}25.76 ml/g) was significantly reduced compared with controls (66.09{+-}14.48 ml/g). The V{sub d} of HED in normal myocardium (49.93{+-}20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial {beta}-AR density was significantly lower in HM (5.49{+-}2.35 pmol/g), infarcted (4.82{+-}2.61 pmol/g) and normal (5.86{+-}1.81 pmol/g) segments of patients compared with healthy controls (8.61{+-}1.32 pmol/g). Noradrenaline uptake-1 mechanism and {beta}-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  4. The contribution of nuclear medicine in the six months following a myocardium infarction

    International Nuclear Information System (INIS)

    Franken, Ph.R.

    2002-01-01

    The techniques of nuclear medicine allow to estimate the myocardial infarction size, to measure the ejection fraction and the ventricles volumes and to identify the presence of high-risk and viable myocardium. This information is essential to evaluate the important complications risks after an acute myocardial infarction, that is to say the infarction recurrence and the cardiac death coming from rhythm troubles or a left ventricle failure. (N.C.)

  5. Effect of hyperbaric oxygenation on carbohydrate metabolism protein synthesis in the myocardium during sustained hypodynamia

    Science.gov (United States)

    Makarov, G. A.

    1980-01-01

    Glycolysis and the intensity of protein synthesis were studied in 140 white male rats in subcellular fractions of the myocardium during 45 day hypodynamia and hyperbaric oxygenation. Hypodynamia increased: (1) the amount of lactic acids; (2) the amount of pyruvic acid; (3) the lactate/pyruvate coefficient; and (4) the activities of aldolase and lactate dehydrogenase. Hyperbaric oxygenation was found to have a favorable metabolic effect on the animals with hypodynamia.

  6. Effect of ethanol and the catalase inhibitor aminotriazole on lipid peroxidation in the rat myocardium

    International Nuclear Information System (INIS)

    Panchenko, L.F.; Pirozhkov, S.V.; Popova, S.V.; Antonenkov, V.D.

    1987-01-01

    The authors study the effect of chronic administration of ethanol and aminotriazole on the level of lipid peroxidation in the ray myocardium. The action of natural and artificial antioxidants on alcohol-induced lipid peroxidation also was studied. To determine the level of chemiluminescence, 1 ml of a sample of nuclear free homogenate or of the total fraction of particles was introduced for radioactivity measurement. After incubation the spontaneous weak luminescence was measured

  7. Healthy aging and myocardium: A complicated process with various effects in cardiac structure and physiology.

    Science.gov (United States)

    Nakou, E S; Parthenakis, F I; Kallergis, E M; Marketou, M E; Nakos, K S; Vardas, P E

    2016-04-15

    It is known that there is an ongoing increase in life expectancy worldwide, especially in the population older than 65years of age. Cardiac aging is characterized by a series of complex pathophysiological changes affecting myocardium at structural, cellular, molecular and functional levels. These changes make the aged myocardium more susceptible to stress, leading to a high prevalence of cardiovascular diseases (heart failure, atrial fibrillation, left ventricular hypertrophy, coronary artery disease) in the elderly population. The aging process is genetically programmed but modified by environmental influences, so that the rate of aging can vary widely among people. We summarized the entire data concerning all the multifactorial changes in aged myocardium and highlighting the recent evidence for the pathophysiological basis of cardiac aging. Keeping an eye on the clinical side, this review will explore the potential implications of the age-related changes in the clinical management and on novel therapeutic strategies potentially deriving from the scientific knowledge currently acquired on cardiac aging process. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Metabolic shifts in the myocardium in the long-term effect of atmospheric pollution on the body

    Energy Technology Data Exchange (ETDEWEB)

    Tsapok, P I; Turdakin, P G; Barkov, L V; Ovcharuk, I N; Protod' iakonova, T N

    1981-04-01

    Metabolic shifts in the myocardium under conditions of long-term exposure of the body to air pollution were studied in experiments on albino rats. Study of the content of protein, RNA, DNA, glycogen, ATP, lactic and pyruvic acids and the activity of lactate dehydrogenase and creatine kinase in the heart muscle allowed the conclusion that the glycolytic processes are intensified, the bioenergic processes are inhibited and the synthesis of protein and RNA are increased in the myocardium of the experimental animals.

  9. Importance of scintigraphy of the myocardium with Csup(99m)-Tc-pyrophosphate in the diagnosis of myocardial ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Botnar' , V I; Dvoskina, I S [Inst. Kardiologii Vsesoyuznogo Kardiologicheskogo Nauchnogo Tsentra AN SSSR

    1983-10-01

    The following aspects of the method of scintigraphy of the myocardium with sup(99m)Tc-pyrophosphate as test sensitivity, possibility of estimating necrosis focus, prognostic importance of the method, scintigram dynamics in case of acute infarction, pyrophosphate accumulation in myocardial cells are considered. Advantages and prospects of the method for visualization of acute myocardium infarction focus and in cases of other pathological states are pointed out.

  10. Minimally invasive orthognathic surgery.

    Science.gov (United States)

    Resnick, Cory M; Kaban, Leonard B; Troulis, Maria J

    2009-02-01

    Minimally invasive surgery is defined as the discipline in which operative procedures are performed in novel ways to diminish the sequelae of standard surgical dissections. The goals of minimally invasive surgery are to reduce tissue trauma and to minimize bleeding, edema, and injury, thereby improving the rate and quality of healing. In orthognathic surgery, there are two minimally invasive techniques that can be used separately or in combination: (1) endoscopic exposure and (2) distraction osteogenesis. This article describes the historical developments of the fields of orthognathic surgery and minimally invasive surgery, as well as the integration of the two disciplines. Indications, techniques, and the most current outcome data for specific minimally invasive orthognathic surgical procedures are presented.

  11. Correlates of minimal dating.

    Science.gov (United States)

    Leck, Kira

    2006-10-01

    Researchers have associated minimal dating with numerous factors. The present author tested shyness, introversion, physical attractiveness, performance evaluation, anxiety, social skill, social self-esteem, and loneliness to determine the nature of their relationships with 2 measures of self-reported minimal dating in a sample of 175 college students. For women, shyness, introversion, physical attractiveness, self-rated anxiety, social self-esteem, and loneliness correlated with 1 or both measures of minimal dating. For men, physical attractiveness, observer-rated social skill, social self-esteem, and loneliness correlated with 1 or both measures of minimal dating. The patterns of relationships were not identical for the 2 indicators of minimal dating, indicating the possibility that minimal dating is not a single construct as researchers previously believed. The present author discussed implications and suggestions for future researchers.

  12. Functional reconstruction of ischemic contracture in the

    Directory of Open Access Journals (Sweden)

    TANG Hao

    2011-04-01

    Full Text Available 【Abstract】Objective: To discuss the method of functional reconstruction of ischemic contracture in the lower limb and propose a classification protocol for ischemic contracture in the lower limb based on its severity and prognosis. Methods: A total of 42 patients with ischemic contracture in the lower limb were included in this study. According to different types of disturbance and degrees of severity, surgical reconstructions consisting of nerve decompression, tendon lengthening or transfer, intrinsic foot muscle release and sural-tibial nerve anastomosis were performed in every patient. Results: Postoperatively, all patients were able to walk on flat ground. Drop foot was corrected in 10 patients, and 5 patients still felt some difficulty during stair activity. Split Achilles tendon transfer to flexor hallucis longus tendon was performed in 12 patients, and their walking stability was improved. Seven patients accepted ipsilateral suraltibial nerve anastomosis, and sensitivity recovery reached to S2 in 2 patients and S3 in 5 patients. Conclusions: Ischemic contracture in the lower limb is a devastating complication after lower limb trauma. The prevention of contracture is much more important than the treatment of an established contracture. Split Achilles tendon transfer to flexor hallucis longus tendon and sural-tibial nerve anastomosis, which was initially implemented by us, could improve the functional recovery of ischemic contracture in lower limbs, and thus provides a new alternative for functional reconstruction of ischemic contracture in the lower limb. Key words: Ischemic contracture; Classification; Recovery of function

  13. Hexavalent Chromium Minimization Strategy

    Science.gov (United States)

    2011-05-01

    Logistics 4 Initiative - DoD Hexavalent Chromium Minimization Non- Chrome Primer IIEXAVAJ ENT CHRO:M I~UMI CHROMIUM (VII Oil CrfVli.J CANCEfl HAnRD CD...Management Office of the Secretary of Defense Hexavalent Chromium Minimization Strategy Report Documentation Page Form ApprovedOMB No. 0704-0188...00-2011 4. TITLE AND SUBTITLE Hexavalent Chromium Minimization Strategy 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  14. Minimal Super Technicolor

    DEFF Research Database (Denmark)

    Antola, M.; Di Chiara, S.; Sannino, F.

    2011-01-01

    We introduce novel extensions of the Standard Model featuring a supersymmetric technicolor sector (supertechnicolor). As the first minimal conformal supertechnicolor model we consider N=4 Super Yang-Mills which breaks to N=1 via the electroweak interactions. This is a well defined, economical......, between unparticle physics and Minimal Walking Technicolor. We consider also other N =1 extensions of the Minimal Walking Technicolor model. The new models allow all the standard model matter fields to acquire a mass....

  15. Clinical role of electrocardiography and of 201Tl scintigraphy exercise tests in diagnosis of ischemic heart disease

    International Nuclear Information System (INIS)

    Jelok, I.; Hatala, R.; Mistrik, A.; Borovicova, F.

    1988-01-01

    The diagnostic potential of ECG and scintigraphy exercise tests is assessed in the light of the experience gained by the authors in the detection of ischemic heart disease, and the complementary character of the two methods is emphasized. The rational and differentiated use of the two noninvasive examination methods requires an optimal clinical assessment of the patient's condition with regard to the probable incidence of the disease. Optimal diagnostic benefit (as compared with the ECG exercise test up to 32%) is shown of scintigraphy, especially in persons with multiple risk factors and atypical chest pain. With regard to the unavailability of perfusion scintigraphy of the myocardium in the authors' clinical practice, they recommend that this examination should mainly be indicated for patients who have a negative or uniterpretable ECG exercise test. (author). 1 tab., 13 refs

  16. Immediate electrical storm of Torsades de Pointes after CRT-D implantation in an ischemic cardiomyopathy patient

    Directory of Open Access Journals (Sweden)

    Adnan Kaya, MD

    2015-06-01

    Full Text Available Cardiac resynchronization therapy with an implantable cardioverter-defibrillator (CRT-D is the preferred treatment for patients with severe heart failure, dyssynchrony, and an increased risk of sudden cardiac death or for primary ventricular arrhythmia survivors. Rarely, left ventricular epicardial pacing can induce ventricular tachyarrhythmia rather than a beneficial effect. We describe an ischemic cardiomyopathy patient who underwent CRT-D therapy and developed sustained torsades de pointes (TdP immediately after switching to biventricular pacing (BVP mode. Here, TdP possibly developed owing to the change in the dispersion of repolarization of the left ventricle myocardium. The diagnosis and management of BVP-induced ventricular arrhythmia is discussed.

  17. Characteristics of Misclassified CT Perfusion Ischemic Core in Patients with Acute Ischemic Stroke.

    Directory of Open Access Journals (Sweden)

    Ralph R E G Geuskens

    Full Text Available CT perfusion (CTP is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up.This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0. Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBV<2.0 ml/100g and infarct on follow-up noncontrast CT and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT regions. False discovery ratio (FDR, defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests.Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml; median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml. Median FDR between patients was 62% (IQR:49%-80%. Median relative mean transit time was 243% (IQR:198%-289% and 342% (IQR:249%-432% for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43-1.79 ml/100g (P<0.01 and 1.38 (IQR:1.15-1.49 ml/100g (P<0.01 for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly.For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly

  18. Transient ischemic attack: diagnostic evaluation.

    Science.gov (United States)

    Messé, Steven R; Jauch, Edward C

    2008-08-01

    A transient ischemic attack portends significant risk of a stroke. Consequently, the diagnostic evaluation in the emergency department is focused on identifying high-risk causes so that preventive strategies can be implemented. The evaluation consists of a facilitated evaluation of the patient's metabolic, cardiac, and neurovascular systems. At a minimum, the following tests are recommended: fingerstick glucose level, electrolyte levels, CBC count, urinalysis, and coagulation studies; noncontrast computed tomography (CT) of the head; electrocardiography; and continuous telemetry monitoring. Vascular imaging studies, such as carotid ultrasonography, CT angiography, or magnetic resonance angiography, should be performed on an urgent basis and prioritized according to the patient's risk stratification for disease. Consideration should be given for echocardiography if no large vessel abnormality is identified.

  19. Minimizing Mutual Couping

    DEFF Research Database (Denmark)

    2010-01-01

    Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna.......Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna....

  20. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail; Pottmann, Helmut; Grohs, Philipp

    2011-01-01

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ

  1. {sup 99m}Tc-glucarate imaging for the early detection of infarct in partially reperfused canine myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gerald; Okada, Christine C.; Hocherman, Sonia D. [University of Oklahoma Health Sciences Center, Tulsa, OK (United States); Liu, Zhonglin [University of Arizona, Tucson, AZ (United States); Hart, Curtis [University of Texas, San Antonio, TX (United States); Khaw, Ban-An [Northeastern University, Boston, MA (United States); Okada, Robert D. [University of Oklahoma Health Sciences Center, Tulsa, OK (United States); University of Tulsa, Department of Biology, Tulsa, OK (United States)

    2006-03-15

    {sup 99m}Tc-glucarate is an imaging agent developed for the detection of acutely infarcted myocardium. The purposes of the current study were to (1) determine whether {sup 99m}Tc-glucarate can detect acute infarct in the setting of only partial minimal reperfusion, (2) study the persistence and time course of scan positivity following coronary occlusion and intravenous tracer injection, (3) assess the ability of {sup 99m}Tc-glucarate to determine infarct size, and (4) compare these data with previous results obtained using a 100% reperfusion model. Six dogs underwent left circumflex (LCx) coronary occlusion for 90 min, followed by 10% epicardial blood flow reperfusion. Fifteen mCi (555 MBq) {sup 99m}Tc-glucarate was injected intravenously 30 min later. Serial gamma camera images were acquired over 240 min. Microsphere blood flow determinations were performed at baseline, during occlusion, during tracer administration, and just before euthanasia. Ex vivo gamma camera images were obtained. Triphenyltetrazolium chloride (TTC) staining was performed to assess infarct size. Qualitatively, {sup 99m}Tc-glucarate images showed a well-defined ''hot spot'' in all six dogs by 30 min after tracer injection (150 min following coronary occlusion), which persisted for 240 min following tracer administration. Quantitatively, there was a significant increase in the LCx/LAD (left anterior descending) counts ratio beginning 10 min after tracer administration (130 min after occlusion), and continuing to 240 min after tracer administration. Tracer retention was 12.0{+-}0.9% for the LAD and 39.0{+-}4.1% for the LCx hot spot zone (p<0.05) at 240 min after {sup 99m}Tc-glucarate injection. The correlation coefficient was 0.90 for infarct size by TTC versus {sup 99m}Tc-glucarate. (orig.)

  2. 99mTc-glucarate imaging for the early detection of infarct in partially reperfused canine myocardium

    International Nuclear Information System (INIS)

    Johnson, Gerald; Okada, Christine C.; Hocherman, Sonia D.; Liu, Zhonglin; Hart, Curtis; Khaw, Ban-An; Okada, Robert D.

    2006-01-01

    99m Tc-glucarate is an imaging agent developed for the detection of acutely infarcted myocardium. The purposes of the current study were to (1) determine whether 99m Tc-glucarate can detect acute infarct in the setting of only partial minimal reperfusion, (2) study the persistence and time course of scan positivity following coronary occlusion and intravenous tracer injection, (3) assess the ability of 99m Tc-glucarate to determine infarct size, and (4) compare these data with previous results obtained using a 100% reperfusion model. Six dogs underwent left circumflex (LCx) coronary occlusion for 90 min, followed by 10% epicardial blood flow reperfusion. Fifteen mCi (555 MBq) 99m Tc-glucarate was injected intravenously 30 min later. Serial gamma camera images were acquired over 240 min. Microsphere blood flow determinations were performed at baseline, during occlusion, during tracer administration, and just before euthanasia. Ex vivo gamma camera images were obtained. Triphenyltetrazolium chloride (TTC) staining was performed to assess infarct size. Qualitatively, 99m Tc-glucarate images showed a well-defined ''hot spot'' in all six dogs by 30 min after tracer injection (150 min following coronary occlusion), which persisted for 240 min following tracer administration. Quantitatively, there was a significant increase in the LCx/LAD (left anterior descending) counts ratio beginning 10 min after tracer administration (130 min after occlusion), and continuing to 240 min after tracer administration. Tracer retention was 12.0±0.9% for the LAD and 39.0±4.1% for the LCx hot spot zone (p 99m Tc-glucarate injection. The correlation coefficient was 0.90 for infarct size by TTC versus 99m Tc-glucarate. (orig.)

  3. Genetics of ischemic stroke: future clinical applications.

    Science.gov (United States)

    Wang, Michael M

    2006-11-01

    Ischemic stroke has long been thought to have a genetic component that is independent of conventional vascular risk factors. It has been estimated that over one half of stroke risk is determined by inherited genes. However, until recently, strong evidence of genetic influence on ischemic stroke has been subject to criticism because the risk factors for stroke are also inherited and because previous studies suffered from limitations imposed by this highly heterogeneous neurological disorder. Recent advances in molecular genetics have led to the identification of specific genetic loci that impart susceptibility to ischemic stroke. We review the studies of these genes and discuss the future potential applications of genetic markers on the management of ischemic stroke patients.

  4. Prognostic Factors in Ischemic Arterial Stroke

    OpenAIRE

    J Gordon Millichap

    2001-01-01

    The predictive value of presenting symptoms, MRI and CT findings, and etiology in the outcome of ischemic arterial childhood stroke was determined in a consecutive series of 31 patients followed at the University Hospital, Rotterdam, The Netherlands.

  5. [Primary emergencies: management of acute ischemic stroke].

    Science.gov (United States)

    Leys, Didier; Goldstein, Patrick

    2012-01-01

    The emergency diagnostic strategy for acute ischemic stroke consists of:--identification of stroke, based on clinical examination (sudden onset of a focal neurological deficit);--identification of the ischemic or hemorrhagic nature by MRI or CT;--determination of the early time-course (clinical examination) and the cause. In all strokes (ischemic or hemorrhagic), treatment consists of:--the same general management (treatment of a life-threatening emergency, ensuring normal biological parameters except for blood pressure, and prevention of complications);--decompressive surgery in the rare cases of intracranial hypertension. For proven ischemic stroke, other therapies consist of: rt-PA for patients admitted with 4.5 hours of stroke onset who have no contraindications, and aspirin (160 to 300 mg) for patients who are not eligible for rt-PA. These treatments should be administered within a few hours. A centralized emergency call system (phone number 15 in France) is the most effective way of achieving this objective.

  6. Acute ischemic stroke prognostication, comparison between ...

    African Journals Online (AJOL)

    Ossama Y. Mansour

    2014-11-20

    Nov 20, 2014 ... patients with acute ischemic stroke in comparison with the NIHSS and the GCS. Methods: .... All patients received a CT scan of the brain on admission. Diagnostic ... adjusted for age, sex, Charlson Index and Oxfordshire. 248.

  7. Ischemic Stroke: MedlinePlus Health Topic

    Science.gov (United States)

    ... Spanish Thrombolytic therapy (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Ischemic Stroke updates ... cardiogenic embolism Stroke - slideshow Thrombolytic therapy Related Health Topics Hemorrhagic Stroke Stroke Stroke Rehabilitation National Institutes of ...

  8. Paraneoplastic Ischemic Stroke: Case Report and Review

    Directory of Open Access Journals (Sweden)

    Murat Sumer

    2008-10-01

    Full Text Available OBJECTIVE: Paraneoplastic etiology is not frequent among cerebrovascular disorders. This rare disorder is interesting with different mechanisms, clinical manifestations and treatment options. Diagnosis may be overlooked for its rarity. We present a paraneoplastic ischemic stroke patient with its clinical and imaging characteristics for recalling this rare disease. CASE: A sixty years old woman with a history of ovarian and colon cancer and liver metastasis admitted with acute left sided hemiplegia. Brain magnetic resonance imaging showed multiple ischemic lesions at the same age. Laboratory findings were compatible with chronic disseminated intravascular coagulopathy. She was anticoagulated but the clinical findings were not changed. She died one month after her discharge from the hospital. CONCLUSIONS: Paraneoplastic ischemic stroke is rare and it should be recognized by the clinician to differentiate from other ischemic strokes by its different mechanisms, imaging characteristics and treatment modalities. Prognosis depends on the characteristics of the primary tumor

  9. Role of neuroinflammation in ischemic stroke

    Institute of Scientific and Technical Information of China (English)

    Rui Liu; Meng-Xian Pan; Jun-Chun Tang; Ya Zhang; Hua-Bao Liao; Yang Zhuang; Dan Zhao; Qi Wan

    2017-01-01

    Ischemic stroke causes the depletion of energy and induce excitotoxicity and neuroinflammation in the brain that results from thrombotic blockage. Neuroinflammation occurs initially depending on activated resident microglia that has the same function as the macrophage. Activated microglia participates in the neuroinflammatory process by phagocytosing the injured brain cells and producing the pro- and anti-inflammatory mediators. In this review, the authors present an overview of the role of microglia in mediating neuroinflammation in ischemic stroke.

  10. Transient central diabetes insipidus following ischemic stroke

    Directory of Open Access Journals (Sweden)

    Muthukrishnan Jayaraman

    2013-01-01

    Full Text Available Central Diabetes Insipidus (CDI following ischemic infarction of the brain has been described as a rare presentation. Posterior pituitary ischemia has also been postulated as a possible cause of idiopathic CDI. We encountered a young male with bilateral extensive ischemic infarction sustained at high altitude, who had transient polyuria due to central diabetes insipidus, requiring desmopressin therapy. DI completely resolved during the course of his neurological recovery.

  11. Hypoxic-Ischemic Encephalopathy after Bee Sting and Treatment with Zolpidem: A Case Report

    Directory of Open Access Journals (Sweden)

    Turgay Demir

    2016-09-01

    Full Text Available Hypoxic-ischemic encephalopathy (HIE, a metabolic encephalopathy, develops as a result of cessation or reduction of oxygen and blood flow to the brain. The clinical picture may vary in severity from minimal neurologic deficits to coma. In living patients, permanent neuropsychological sequelae can develop. Herein, we present a case of HIE that occured after anaphylactic reaction due to bee sting, which was treatedm with zolpidem.

  12. Dynamic MRI of ferumoxide-labeled bone mesenchmal stem cells after transplantation in infarcted myocardium

    International Nuclear Information System (INIS)

    Liu Qiong; Zhao Shihua; Lu Minjie; Jiang Shiliang; Yan Chaowu; Zhang Yan; Meng Liang; Tang Yue; Meng Xianmin; Wei Yingjie; Wang Qingzhi

    2009-01-01

    Objective: To investigate the ability of magnetic resonance imaging (MRI) in tracking magnetically labeled mesenchymal stem cells (MR-MSCs) in a swine myocardial infarction (MI) model. Methods: Adult Chinese mini-pigs (n=6) were subjected to open-chest experimental MI operation. Their autogeneic bone marrow-derived mesenchymal stem cells (MSCs) was cultured and doubly labeled with ferumoxides and DAPI. On the 14 th day after MSCs transplantation, the size and location of the myocardial infarction were assessed by using delayed-enhancement MRI (DE-MRI). Then the labeled MSCs were injected intramyocardially into peri-infarct zone and normal myocardium. At 24 hrs and 3 weeks after injection, the contrast and the volume of the MR-MSCs hypointense lesion from the MR images were acquired, and the contrast was determined using the difference in signal intensity between the hypointense and normal myocardium divided by signal intensity of the normal region. After humane euthanasia, the heart was excised and histology corresponding to MRI slices that demonstrated MR-MSCs lesions was performed. Repeated-measures ANOVA and a paired t test were used for comparison of the contrast and the volume of the MR-MSCs hypointense lesion at different time points. Comparisons between independent groups were performed with the standard Student t test. Results: The labeling efficiency of ferumoxides and DAPI was 100%. On the 14 th day after the MI operation, the average percentage of infracted myocardial area was (33.6±8.9)%. Twenty- four hours after MSCs transplantation, MSCs injection sites appeared as ovoid hypointensive lesions with sharp border on T 2 * images. At 24 h after injection, the signal contrast [(67.00±5.48)% vs (61.92±7.76)%,t=1.65, P=0.1158] and the size [(0.56±0.24) cm 2 vs (0.52±0.25) cm 2 , t=0.39, P=0.7044] of the lesions showed no statistical difference between the peri-infarct zone and the normal myocardium. At 3 weeks after injection, the signal contrast

  13. Kinetics of thallium-201 in reperfused canine myocardium after coronary artery occlusion

    International Nuclear Information System (INIS)

    Okada, R.D.

    1984-01-01

    To study the kinetics of thallium-201 in nonsalvaged acutely infarcted myocardium and salvaged myocardium, the tracer was administered after experimental left anterior descending coronary artery reperfusion 2 hours after occlusion. In 19 dogs, thallium activity was then monitored for 4 hours in the reperfused anterior wall and normal posterior wall using miniature cadmium telluride radiation detectors. After sacrifice, 13 of the dogs were found to have an infarcted anterior wall by triphenyltetrazolium-chloride staining. In these dogs, mean (+/- standard deviation) fractional 4 hour thallium clearance was 0.33 +/- 0.08 for the infarct zone and 0.15 +/- 0.06 for the normal control zone (p less than 0.001). When computer-modeled, the clearance curve from the infarct zone was biexponential. The second exponential clearance curve from the infarct zone began 19.1 +/- 3.2 minutes after tracer administration, and was indistinguishable from the monoexponential clearance curve from the normal control zone. Thallium clearance from the blood pool was triexponential, the final exponential clearance curve being indistinguishable from the normal control zone clearance curve. Six dogs were found to have a salvaged noninfarcted anterior wall by triphenyltetrazolium-chloride staining. In these dogs, mean fractional 4 hour thallium clearance was 0.20 +/- 0.07 for the reperfused zone, and 0.19 +/- 0.08 for the normal control zone (p . NS). When computer-modeled, clearance curves for the reperfused and control zones were monoexponential. The monoexponential clearance curve for the salvaged reperfused zone was indistinguishable from the monoexponential clearance curve for normal myocardium

  14. Effects of acute and chronic uremia on active cation transport in rat myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Druml, W.; Kelly, R.A.; England, B.K.; O' Hara, D.S.; Mitch, W.E. (Brigham and Women' s Hospital, Boston, MA (USA))

    1990-12-01

    As abnormalities of active cation transport could contribute to the genesis of uremic cardiomyopathy, we investigated myocardial sodium pump function in rats with acute renal failure (ARF) and with a model of experimental chronic renal failure (CRF) that has metabolic similarities to advanced chronic uremia in humans. CRF rats were hypertensive and had left ventricular hypertrophy (33% higher heart:body weight ratio; P less than 0.01) at four weeks compared to pair-fed sham-operated rats. Importantly, both ouabain- and furosemide-sensitive 86Rb uptake rates were unchanged in left ventricular myocardial slices from CRF, and the intracellular sodium concentration was not different from that of control rats even though skeletal muscle sodium was increased, as we found previously. Insulin-stimulated, ouabain-sensitive 86Rb influx was also preserved. There also were no abnormalities in myocardium cation transport in rats with ARF. However, (3H)ouabain binding was decreased 45% in CRF rats (P less than 0.01); it was unchanged in acute uremia. Decreased ouabain binding in chronic uremia was due entirely to fewer low affinity (3H)ouabain binding sites (the binding affinity for ouabain was unaffected). We conclude that in chronic, (but not acute) renal failure, sodium pump number is reduced in myocardium but intracellular sodium is unchanged and active cation flux rates are maintained. These results emphasize that in rats with chronic uremia, intracellular sodium homeostasis is preserved in myocardium, despite the presence of marked abnormalities of active cation transport in skeletal muscle that are characteristic of chronic uremia.

  15. Analysis of immune cell populations in atrial myocardium of patients with atrial fibrillation or sinus rhythm.

    Directory of Open Access Journals (Sweden)

    Natalia Smorodinova

    Full Text Available Atrial fibrillation (AF is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients.The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR.We examined 46 subjects (19 with AF, and 27 in SR undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry.The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample.An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence.

  16. Development of an in vivo method for determining material properties of passive myocardium

    Directory of Open Access Journals (Sweden)

    Espen Remme

    2004-10-01

    Full Text Available Calculation of mechanical stresses and strains in the left ventricular (LV myocardium by the finite element (FE method relies on adequate knowledge of the material properties of myocardial tissue. In this paper we present a model-based estimation procedure to characterize the stress-strain relationship in passive LV myocardium. A 3D FE model of the LV myocardium was used, which included morphological fiber and sheet structure and a nonlinear orthotropic constitutive law with different stiffness in the fiber, sheet and sheet-normal directions. The estimation method was based on measured wall strains. We analyzed the method's ability to estimate the material parameters by generating a set of synthetic strain data by simulating the LV inflation phase with known material parameters. In this way we were able to verify the correctness of the solution and to analyze the effects of measurement and model error on the solution accuracy and stability. A sensitivity analysis was performed to investigate the observability of the material parameters and to determine which parameters to estimate. The results showed a high degree of coupling between the parameters governing the stiffness in each direction. Thus, only one parameter in each of the three directions was estimated. For the tested magnitudes of added noise and introduced model errors, the resulting estimated stress-strain characteristics in the fiber and sheet directions converged with good accuracy to the known relationship. The sheet-normal stress-strain relationship had a higher degree of uncertainty as more noise was added and model error was introduced.

  17. JIGSAW PUZZLE IMPROVE FINE MOTOR ABILITIES OF UPPER EXTREMITIES IN POST-STROKE ISCHEMIC CLIENTS

    Directory of Open Access Journals (Sweden)

    Kusnanto Kusnanto

    2017-06-01

    Full Text Available Introduction: Ischemic stroke is a disease caused by focal cerebral ischemia, where is a decline in blood flow that needed for neuronal metabolism, leading to neurologic deficit include motor deficit such as fine motor skills impairment. Therapy of fine motor skills disorders is to improve motor function, prevent contractures and complications. These study aimed to identify the effect of playing Jigsaw Puzzle on muscle strength, extensive motion, and upper extremity fine motor skills in patients with ischemic stroke at Dr. Moewardi Hospital, Surakarta. Methods: Experimental Quasi pre-posttest one group control. The number of samples were 34 respondents selected using purposive sampling technique. The samples were divided into intervention and control groups. The intervention group was 17 respondents who were given standard treatment hospital and played Jigsaw Puzzle 2 times a day for six days. Control group is one respondent given by hospital standard therapy without given additional Jigsaw Puzzle game. Evaluation of these research is done on the first and seventh day for those groups. Result: The results showed that muscle strength, the range of joint motion and fine motor skills of upper extremities increased (p = 0.001 significantly after being given the Jigsaw Puzzle games. These means playing Jigsaw Puzzle increase muscle strength, the range of joint motion and upper extremity fine motor skill of ischemic stroke patients. Discussion and conclusion: Jigsaw puzzle game administration as additional rehabilitation therapy in upper extremity fine motor to minimize the occurrence of contractures and motor disorders in patients with ischemic stroke. Jigsaw puzzle game therapy capable of creating repetitive motion as a key of neurological rehabilitation in Ischemic Stroke. This study recommends using jigsaw puzzle game as one of intervention in the nursing care of Ischemic Stroke patients.

  18. Minimizing Exposure at Work

    Science.gov (United States)

    ; Environment Human Health Animal Health Safe Use Practices Food Safety Environment Air Water Soil Wildlife Home Page Pesticide Health and Safety Information Safe Use Practices Minimizing Exposure at Work Pesticides - Pennsylvania State University Cooperative Extension Personal Protective Equipment for Working

  19. Minimalism. Clip and Save.

    Science.gov (United States)

    Hubbard, Guy

    2002-01-01

    Provides background information on the art movement called "Minimalism" discussing why it started and its characteristics. Includes learning activities and information on the artist, Donald Judd. Includes a reproduction of one of his art works and discusses its content. (CMK)

  20. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail

    2011-10-30

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ) + λ(sin φ, cos φ, 0), where A,B,C,D ε ℝ are fixed. To achieve invariance under Laguerre transformations, we also derive all Laguerre minimal surfaces that are enveloped by a family of cones. The methodology is based on the isotropic model of Laguerre geometry. In this model a Laguerre minimal surface enveloped by a family of cones corresponds to a graph of a biharmonic function carrying a family of isotropic circles. We classify such functions by showing that the top view of the family of circles is a pencil. © 2011 Springer-Verlag.

  1. Genetically elevated C-reactive protein and ischemic vascular disease

    DEFF Research Database (Denmark)

    Zacho, J.; Tybjaerg-Hansen, A.; Jensen, J.S.

    2008-01-01

    Background: Elevated levels of C-reactive protein (CRP) are associated with increased risks of ischemic heart disease and ischemic cerebrovascular disease. We tested whether this is a causal association. Methods: We studied 10,276 persons from a general population cohort, including 1786 in whom...... ischemic heart disease developed and 741 in whom ischemic cerebrovascular disease developed. We examined another 31,992 persons from a cross-sectional general population study, of whom 2521 had ischemic heart disease and 1483 had ischemic cerebrovascular disease. Finally, we compared 2238 patients...... with ischemic heart disease with 4474 control subjects and 612 patients with ischemic cerebrovascular disease with 1224 control subjects. We measured levels of high-sensitivity CRP and conducted genotyping for four CRP polymorphisms and two apolipoprotein E polymorphisms. Results: The risk of ischemic heart...

  2. The effect of percutaneous transmyocardial laser revascularization on left ventricular function in a porcine model of hibernating myocardium

    International Nuclear Information System (INIS)

    Almeda, Francis Q.; Glock, Dana; Sandelski, Joanne; Ibrahim, Osama; Macioch, James E.; Allen, Trisha; Dainauskas, John R.; Parrillo, Joseph E.; Snell, R. Jeffrey; Schaer, Gary L.

    2004-01-01

    Background: Hibernating myocardium is defined as a state of persistently impaired myocardial function at rest due to reduced coronary blood flow that can partially or completely be restored to normal if the myocardial oxygen supply/demand relationship is favorably altered. Percutaneous laser revascularization (PMR) is an emerging catheter-based technique that involves creating channels in the myocardium, directly through a percutaneous approach with a laser delivery system, and has been shown to reduce symptoms in patients with severe refractory angina; however, its effect on improving regional wall motion abnormalities in hibernating myocardium has not been clearly established. We sought to determine the effect of PMR using the Eclipse System (Cardiogenesis) on left ventricular function in a porcine model of hibernating myocardium. Methods: A model of hibernating myocardium was created by placement of an ameroid constrictor in the proximal left anterior descending artery of a 35 kg male Yorkshire pig. The presence of hibernating myocardium was confirmed with dobutamine stress echocardiography (DSE) and defined as severe hypocontractility at rest, with an improvement in systolic wall thickening with low-dose dobutamine in myocardial regions with a subsequent deterioration in function at peak stress (biphasic response). After the demonstration of hibernating myocardium, PMR was performed in the area of hypocontractile function, and the serial echocardiography was performed. The echocardiograms were reviewed by an experienced echocardiologist blinded to the results, and regional wall motion was assessed using the American Society of Echocardiography Wall Motion Score. Six weeks after PMR, the animal was sacrificed and the heart sent for histopathologic studies. Results: A comparison of the regional wall motion function of the area distal to the ameroid constrictor and in the contralateral wall at baseline, post-ameroid placement, and post-PMR was performed

  3. Minimal and careful processing

    OpenAIRE

    Nielsen, Thorkild

    2004-01-01

    In several standards, guidelines and publications, organic food processing is strongly associated with "minimal processing" and "careful processing". The term "minimal processing" is nowadays often used in the general food processing industry and described in literature. The term "careful processing" is used more specifically within organic food processing but is not yet clearly defined. The concept of carefulness seems to fit very well with the processing of organic foods, especially if it i...

  4. Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium

    OpenAIRE

    Du, Xiaoyi; Schoemaker, Regien; Bos, Egbert; Saxena, Pramod Ranjan

    1995-01-01

    textabstractIn the human isolated myocardium, acetylcholine (10−9 to 10−3 M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised contractility achieved by exposure to noradrenaline (10−5 M), only negative inotropic effects were observed in both atria and ventricles. Atropine (10−6 M), but not propranolol (10−6 M), antagonized bot...

  5. Pre- and post-synaptic sympathetic function in human hibernating myocardium

    International Nuclear Information System (INIS)

    John, Anna S.; Pepper, John R.; Dreyfus, Gilles D.; Pennell, Dudley J.; Mongillo, Marco; Khan, Muhammad T.; Depre, Christophe; Rimoldi, Ornella E.; Camici, Paolo G.

    2007-01-01

    Impaired pre-synaptic noradrenaline uptake-1 mechanism has been reported in a swine model of hibernating myocardium (HM). To ascertain whether adrenergic neuroeffector abnormalities are present in human HM, we combined functional measurements in vivo using cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) to assess pre- and post-synaptic sympathetic function. Twelve patients with coronary artery disease and chronic left ventricular (LV) dysfunction underwent CMR at baseline and 6 months after bypass for assessment of regional and global LV function and identification of segments with reversible dysfunction. Before surgery, myocardial noradrenaline uptake-1 ([ 11 C]meta-hydroxy-ephedrine; HED) and β-adrenoceptor (β-AR) density ([ 11 C]CGP-12177) were measured with PET. Patient PET data were compared with those in 18 healthy controls. The volume of distribution (V d ) of HED in HM (47.95±28.05 ml/g) and infarcted myocardium (42.69±25.76 ml/g) was significantly reduced compared with controls (66.09±14.48 ml/g). The V d of HED in normal myocardium (49.93±20.48 ml/g) of patients was also lower than that in controls and the difference was close to statistical significance (p=0.06). Myocardial β-AR density was significantly lower in HM (5.49±2.35 pmol/g), infarcted (4.82±2.61 pmol/g) and normal (5.86±1.81 pmol/g) segments of patients compared with healthy controls (8.61±1.32 pmol/g). Noradrenaline uptake-1 mechanism and β-AR density are reduced in the myocardium of patients with chronic LV dysfunction and evidence of HM. The increased sympathetic activity to the heart in these patients is a generalised rather than regional phenomenon which is likely to contribute to the remodelling process of the whole LV rather than playing a causative role in HM. (orig.)

  6. Adaptation of the cardiovascular system to postinfarction cardiosclerosis in rats with congenital adrenoreactivity of the myocardium.

    Science.gov (United States)

    Usacheva, M A; Popkova, E V; Smirnova, E A; Saltykova, V A; Belkina, L M

    2007-12-01

    Three months after myocardial infarction the severity of heart failure and size of postinfarction scars in August rats with inherently reduced adrenoreactivity of the myocardium were similar to those in Wistar rats. The mortality rate in August rats was 2.5-fold lower than in Wistar rats. During the postinfarction period, myocardial adrenoreactivity in August rats remained lower, while the efficiency of cardiac function was 62% higher than in Wistar rats. The incidence of epinephrine-induced arrhythmias in August rats was much lower than in Wistar rats.

  7. Method for radio imaging the myocardium of mammals using radio-labelled lipophil cations

    International Nuclear Information System (INIS)

    1984-01-01

    The invention relates to a method for the radio imaging of myocardia of mammals by concentrating a radiolabelled cation in myocardial tissue and by producing a radiograph using imaging techniques. According to the invention, it is found that a group of substances shows a preference to myocardial tissues upon intravenous injection in mammals. The characteristic of the invention is that radiolabelled quaternary ammonium, quaternary phosphorous or quaternary arsenic compounds with at least two aryl groups are intravenously injected. These substances provide a sufficiently high radioactivity giving an approved diagnostic image of the myocardium. (G.J.P.)

  8. 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)

  9. MRI in ischemic brain diseases

    International Nuclear Information System (INIS)

    Steinbrich, W.; Friedmann, G.; Pawlik, G.; Boecher-Schwarz, H.G.; Heiss, W.D.

    1986-01-01

    The results of MRI and CT in 55 patients with brain infarcts were compared; in 26 of these cases an additional PET examination was obtained in order to study the regional glucose utilisation. MRI was superior to CT, demonstrating 11% more of the infarcts, particularly during the first 24 hours, in small lesions confined to the grey or subcortical white matter and in infratentorial ischemic lesion. On the other hand, only CT was able to show fresh hemorrhage, although MRI was the method of choice to demonstrate old blood collections. To characterise the follow up of an infarct, CT and MRI were similar, except the marginal contrast enhancement sometimes demonstrated by CT studies between the 2nd and 4th week after stroke event. PET was inferior to show details because of its poorer spatial resolution, but anyhow had a high sensitivity and provided additional informations concerning secondary inactivations of brain areas not directly damaged. Additionally PET was able to demonstrate areas of anaerobic glycolysis and lesions of diminished glucose utilisation in TIAs. Small areas of gliosis in the white matter of the cerebral hemispheres were frequently found in patients with cerebro-vascular diseases; they were best shown by MRI, but do not correlate with the extent of vascular stenoses or occlusions, shown by angiography. (orig) [de

  10. Smoking Cessation Intervention After Ischemic Stroke or Transient Ischemic Attack. A Randomized Controlled Pilot Trial

    DEFF Research Database (Denmark)

    Brunner Frandsen, Nicole; Sørensen, Margit; Hyldahl, Tanja Kirstine

    2012-01-01

    BACKGROUND: Smoking cessation is widely recommended for secondary stroke prevention. However, little is known about the efficacy of smoking cessation intervention after stroke or transient ischemic attack (TIA). METHODS: Ninety-four smokers under age 76, admitted with ischemic stroke or TIA were ...

  11. Quantitative Measurement of Physical Activity in Acute Ischemic Stroke and Transient Ischemic Attack

    DEFF Research Database (Denmark)

    Strømmen, Anna Maria; Christensen, Thomas; Jensen, Kai

    2014-01-01

    BACKGROUND AND PURPOSE: The purpose of this study was to quantitatively measure and describe the amount and pattern of physical activity in patients within the first week after acute ischemic stroke and transient ischemic attack using accelerometers. METHODS: A total of 100 patients with acute is...

  12. Occurrence and predictors of persistent impaired glucose tolerance after acute ischemic stroke or transient ischemic attack

    NARCIS (Netherlands)

    S. Fonville (Susanne); H.M. den Hertog (Heleen); A.A.M. Zandbergen (Adrienne); P.J. Koudstaal (Peter Jan); H.F. Lingsma (Hester)

    2014-01-01

    textabstractBackground Impaired glucose tolerance is often present in patients with a transient ischemic attack (TIA) or ischemic stroke and doubles the risk of recurrent stroke. This impaired glucose tolerance can be transient, reflecting an acute stress response, or persistent, representing

  13. Waste minimization assessment procedure

    International Nuclear Information System (INIS)

    Kellythorne, L.L.

    1993-01-01

    Perry Nuclear Power Plant began developing a waste minimization plan early in 1991. In March of 1991 the plan was documented following a similar format to that described in the EPA Waste Minimization Opportunity Assessment Manual. Initial implementation involved obtaining management's commitment to support a waste minimization effort. The primary assessment goal was to identify all hazardous waste streams and to evaluate those streams for minimization opportunities. As implementation of the plan proceeded, non-hazardous waste streams routinely generated in large volumes were also evaluated for minimization opportunities. The next step included collection of process and facility data which would be useful in helping the facility accomplish its assessment goals. This paper describes the resources that were used and which were most valuable in identifying both the hazardous and non-hazardous waste streams that existed on site. For each material identified as a waste stream, additional information regarding the materials use, manufacturer, EPA hazardous waste number and DOT hazard class was also gathered. Once waste streams were evaluated for potential source reduction, recycling, re-use, re-sale, or burning for heat recovery, with disposal as the last viable alternative

  14. Cardioprotective effect of the Hibiscus rosa sinensis flowers in an oxidative stress model of myocardial ischemic reperfusion injury in rat

    Science.gov (United States)

    Gauthaman, Karunakaran K; Saleem, Mohamed TS; Thanislas, Peter T; Prabhu, Vinoth V; Krishnamoorthy, Karthikeyan K; Devaraj, Niranjali S; Somasundaram, Jayaprakash S

    2006-01-01

    Background The present study investigates the cardioprotective effects of Hibiscus rosa sinensis in myocardial ischemic reperfusion injury, particularly in terms of its antioxidant effects. Methods The medicinal values of the flowers of Hibiscus rosa sinensis (Chinese rose) have been mentioned in ancient literature as useful in disorders of the heart. Dried pulverized flower of Hibiscus rosa sinensis was administered orally to Wistar albino rats (150–200 gms) in three different doses [125, 250 and 500 mg/kg in 2% carboxy methyl cellulose (CMC)], 6 days per week for 4 weeks. Thereafter, rats were sacrificed; either for the determination of baseline changes in cardiac endogenous antioxidants [superoxide dismutase, reduced glutathione and catalase] or the hearts were subjected to isoproterenol induced myocardial necrosis. Results There was significant increase in the baseline contents of thiobarbituric acid reactive substances (TBARS) [a measure of lipid per oxidation] with both doses of Hibiscus Rosa sinensis. In the 250 mg/kg treated group, there was significant increase in superoxide dismutase, reduced glutathione, and catalase levels but not in the 125 and 500 mg/kg treated groups. Significant rise in myocardial thiobarbituric acid reactive substances and loss of superoxide dismutase, catalase and reduced glutathione (suggestive of increased oxidative stress) occurred in the vehicle treated hearts subjected to in vivo myocardial ischemic reperfusion injury. Conclusion It may be concluded that flower of Hibiscus rosa sinensis (250 mg/kg) augments endogenous antioxidant compounds of rat heart and also prevents the myocardium from isoproterenol induced myocardial injury. PMID:16987414

  15. Features of the temperature response to a double cuff-occlusion of the upper limbs: remote ischemic preconditioning aspect

    Science.gov (United States)

    Sagaidachnyi, A. A.; Fomin, A. V.; Mayskov, D. I.; Skripal, A. V.; Usanov, D. A.

    2018-04-01

    The essence of the phenomenon of ischemic preconditioning is increasing myocardium resistance to long periods of ischemia that occurs after several short ischemia-reperfusion periods. The aim of this pilot study was to determine the temperature and vascular response in double brachial occlusions and to assess the prospects of using this maneuver for remote ischemic preconditioning. Infrared thermography-based measurements were used to assess hemodynamics both left and right hands during the baseline, ischemia and hyperemia periods. Double ischemia with a period of 2 min was implemented by a cuff compression of the brachial artery of the right hand. A study group was constituted of eight men and six women without cardiovascular abnormalities at the age of 22 to 35 years. As a result, we have determined that a temperature and vascular response to ischemia of right hand is accompanied by the vascular reaction of the contralateral left hand, especially after the inflation and deflation of the cuff. These vascular reactions are reproducible, systemic and appear to be at least neurological in nature. An experimental confirmation of the systemic vascular «training effect» after multiple brachial ischemia-reperfusion periods is a subject of further investigations.

  16. Interaction of metabolic and respiratory acidosis with α and β-adrenoceptor stimulation in rat myocardium.

    Science.gov (United States)

    Biais, Matthieu; Jouffroy, Romain; Carillion, Aude; Feldman, Sarah; Jobart-Malfait, Aude; Riou, Bruno; Amour, Julien

    2012-12-01

    The effects of acute respiratory versus metabolic acidosis on the myocardium and their consequences on adrenoceptor stimulation remain poorly described. We compared the effects of metabolic and respiratory acidosis on inotropy and lusitropy in rat myocardium and their effects on the responses to α- and β-adrenoceptor stimulations. The effects of acute respiratory and metabolic acidosis (pH 7.10) and their interactions with α and β-adrenoceptor stimulations were studied in isolated rat left ventricular papillary muscle (n=8 per group). Intracellular pH was measured using confocal microscopy and a pH-sensitive fluorophore in isolated rat cardiomyocytes. Data are mean percentages of baseline±SD. Respiratory acidosis induced more pronounced negative inotropic effects than metabolic acidosis did both in isotonic (45±3 versus 63±6%, Prespiratory or metabolic acidosis. The inotropic response to β-adrenergic stimulation was impaired only in metabolic acidosis (137±12 versus 200±33%, Pacidosis. The lusitropic response to β-adrenergic stimulation was not modified by respiratory or metabolic acidosis. Acute metabolic and respiratory acidosis induce different myocardial effects related to different decreases in intracellular pH. Only metabolic acidosis impairs the positive inotropic effect of β-adrenergic stimulation.

  17. Study of shape memory alloy fibers for the development of artificial myocardium.

    Science.gov (United States)

    Hassoulas, Ioannis A; Ladopoulos, Vlassios S; Kalogerakos, Paris-Dimitrios K

    2010-01-01

    Circulatory support devices are employed to treat heart failure. Such a device could be made from shape memory alloy (SMA) fibers. These Ni-Ti fibers contract when electric current flows through them, thus resembling artificial muscles. An artificial myocardium device made from SMA fibers can directly compress the epicardial surface of a failing heart, thus contributing to the pumping action. Unlike modern mechanical circulatory support devices, there is no blood-contacting surface to provoke thromboembolism, hemorrhage, inflammatory response or hemolysis. The experimental setup permitted a detailed study of a sample SMA fiber with great accuracy while the ambient temperature was controlled to resemble that of the human body. The current profile through the fiber was controlled (current shaping, CS) by a microcontroller and a portable computer. Parameters such as strain, contraction and relaxation velocities and the effect of ambient temperature were measured. The contraction and relaxation velocities were measured after applying various effective currents. It was found that the contraction velocity could be manipulated to reach that of the healthy myocardium through CS. On the other hand, the relaxation velocity was independent of the contraction velocity. A cardiac assist device can be made from SMA fibers. More studies need to be conducted in this direction.

  18. Effects of hydroxyl radical induced-Injury in atrial versus ventricular myocardium of dog and rabbit

    Directory of Open Access Journals (Sweden)

    Nitisha Hiranandani

    2010-09-01

    Full Text Available Aim: Despite the widespread use of ventricular tissue in the investigation involving hydroxyl-radical (OH* injury, one of the most potent mediators in ischemia-reperfusion injury, little is known about the impact on atrial myocardium. In this study we thus compared the OH*-induced injury response between atrial and right ventricular muscles from both rabbits and dogs under identical experimental conditions. Methods: Small, contracting ventricular and atrial rabbit and dog trabeculae were directly exposed to OH*, and contractile properties were examined and quantified. Results: A brief OH* exposure led to transient rigor like contracture with marked elevation of diastolic tension and depression of developed force. Although the injury response showed similarities between atrial and ventricular myocardium, there were significant differences as well. In rabbit atrial muscles, the development of the contracture and its peak was much faster as compared to ventricular muscles. Also, at the peak of contracture, both rabbit and dog atrial muscles show a lesser degree of contractile dysfunction. Conclusion: These results indicate that both atrial and ventricular muscles develop a rigor like contracture after acute OH*-induced injury, and atrial muscles showed a lesser degree of contractile dysfunction. Comparison of dog versus rabbit tissue shows that the response was similar in magnitude, but slower to develop in dog tissue.

  19. Effects of allocryptopine on outward potassium current and slow delayed rectifier potassium current in rabbit myocardium.

    Science.gov (United States)

    Fu, Yi-Cheng; Zhang, Yu; Tian, Liu-Yang; Li, Nan; Chen, Xi; Cai, Zhong-Qi; Zhu, Chao; Li, Yang

    2016-05-01

    Allocryptopine (ALL) is an effective alkaloid of Corydalis decumbens (Thunb.) Pers. Papaveraceae and has proved to be anti-arrhythmic. The purpose of our study is to investigate the effects of ALL on transmural repolarizing ionic ingredients of outward potassium current (I to) and slow delayed rectifier potassium current (I Ks). The monophasic action potential (MAP) technique was used to record the MAP duration of the epicardium (Epi), myocardium (M) and endocardium (Endo) of the rabbit heart and the whole cell patch clamp was used to record I to and I Ks in cardiomyocytes of Epi, M and Endo layers that were isolated from rabbit ventricles. The effects of ALL on MAP of Epi, M and Endo layers were disequilibrium. ALL could effectively reduce the transmural dispersion of repolarization (TDR) in rabbit transmural ventricular wall. ALL decreased the current densities of I to and I Ks in a voltage and concentration dependent way and narrowed the repolarizing differences among three layers. The analysis of gating kinetics showed ALL accelerated the channel activation of I to in M layers and partly inhibit the channel openings of I to in Epi, M and Endo cells. On the other hand, ALL mainly slowed channel deactivation of I Ks channel in Epi and Endo layers without affecting its activation. Our study gives partially explanation about the mechanisms of transmural inhibition of I to and I Ks channels by ALL in rabbit myocardium. These findings provide novel perspective regarding the anti-arrhythmogenesis application of ALL in clinical settings.

  20. Biophysical foundations for the study of the electrical excitability and action potential propagation in myocardium

    International Nuclear Information System (INIS)

    Suarez Antola, R.

    1991-01-01

    The electric current flow in the heterogeneous and anysotropic volume conductor of the myocardium is studied. The equations of bidomain theory are derived using an approach framed in the theory of averaged fields, introducing microscopic, mesoscopic and macroscopic spatial scales. However, the procedure, compatible with the histological and the anatomical details of the organ, is different from the multiple scale asymptotic expansions usually applied in homogeneization problems. A probabilistic approach framed in large numbers theorems is used to derive the equation for membrane ionic current from the stochastic activity of the channels at the microscopic level. An operational procedure suitable to define a sharp bidomain boundary from the fuzzy distribution of structural details and physical properties at the histological level is given. The problem of threshold is studied. The sizes and shapes of critical masses of cardiac cells that must be depolarized above threshold in order to produce a propagated action potential are determined by an approximate analytical procedure. The concept of family of threshold patterns for the emergence of action potentials in the heart is introduced. This concept is applied to discuss the conditions of emergence of ectopic focus. Analytical formulae are derived, for the time constant and the rheobase for electrical stimulation of the myocardium. These formulae are in good agreement with known experimental results. New experiments that could be done to confirm or reject them are suggested

  1. Oxygen supply and oxidative phosphorylation limitation in rat myocardium in situ.

    Science.gov (United States)

    Kreutzer, U; Mekhamer, Y; Chung, Y; Jue, T

    2001-05-01

    The 1H-NMR signal of the proximal histidyl-N(delta)H of deoxymyoglobin is detectable in the in situ rat myocardium and can reflect the intracellular PO2. Under basal normoxic conditions, the cellular PO2 is sufficient to saturate myoglobin (Mb). No proximal histidyl signal of Mb is detectable. On ligation of the left anterior descending coronary artery, the Mb signal at 78 parts/million (ppm) appears, along with a peak shoulder assigned to the corresponding signal of Hb. During dopamine infusion up to 80 microg. kg(-1) x min(-1), both the heart rate-pressure product (RPP) and myocardial oxygen consumption (MVO2) increase by about a factor of 2. Coronary flow increases by 84%, and O2 extraction (arteriovenous O2 difference) rises by 31%. Despite the increased respiration and work, no deoxymyoglobin signal is detected, implying that the intracellular O2 level still saturates MbO2, well above the PO2 at 50% saturation of Mb. The phosphocreatine (PCr) level decreases, however, during dopamine stimulation, and the ratio of the change in P(i) over PCr (DeltaP(i)/PCr) increases by 0.19. Infusion of either pyruvate, as the primary substrate, or dichloroacetate, a pyruvate dehydrogenase activator, abolishes the change in DeltaP(i)/PCr. Intracellular O2 supply does not limit MVO2, and the role of ADP in regulating respiration in rat myocardium in vivo remains an open question.

  2. [Surgery of refractory ischemic arrhythmia].

    Science.gov (United States)

    Viganò, M; Graffigna, A; Salerno, G

    1992-03-01

    Since June 1980, 138 patients have undergone surgical treatment for refractory ventricular tachycardia due to ischemic heart disease. Electrically guided surgical ablation (EGSA) of the focus was performed in 117 patients, while 14 patients underwent application of automatic implantable cardioverter-defibrillator (AICD), and 8 patients underwent heart transplantation. During the whole period considered, among the EGSA patients an operative mortality of 13 patients was observed (11.4%), with a late mortality of another 14 patients (13.4%). Two early and six late recurrences were described, and 4 cases of sudden or unexplained death, with 2 cases clearly due to an arrhythmic event. Multivariate analysis showed preoperative ejection fraction lower than 25% as a powerful predictor of early mortality (32% vs 0%). Actuarial survival rate of patients with LVEF lower than 25% was 67 +/- 12% vs 95 +/- 2% at one year and 37 +/- 25% vs 94 +/- 8% at 8 years. A high operative mortality was then observed in patients who underwent aneurysmectomy alone or visually guided procedures as compared to electrically guided procedures (75% or 3 deaths out of 4 patients vs 8.5% or 10 out of 113 patients, respectively). Patients who received an AICD with or without associated procedures showed 1 case of in-hospital mortality and no late mortality; in 6 patients at least one shock was delivered; in two patients the AICD was implanted during an EGSA procedure, due to multiple or difficult origins of the arrhythmias. Of patients who underwent heart transplantation one case of later mortality was observed due to malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Ischemic Tolerance of the Brain and Spinal Cord: A Review.

    Science.gov (United States)

    Yunoki, Masatoshi; Kanda, Takahiro; Suzuki, Kenta; Uneda, Atsuhito; Hirashita, Koji; Yoshino, Kimihiro

    2017-11-15

    Ischemic tolerance is an endogenous neuroprotective phenomenon induced by sublethal ischemia. Ischemic preconditioning (IPC), the first discovered form of ischemic tolerance, is widely seen in many species and in various organs including the brain and the spinal cord. Ischemic tolerance of the spinal cord is less familiar among neurosurgeons, although it has been reported from the viewpoint of preventing ischemic spinal cord injury during aortic surgery. It is important for neurosurgeons to have opportunities to see patients with spinal cord ischemia, and to understand ischemic tolerance of the spinal cord as well as the brain. IPC has a strong neuroprotective effect in animal models of ischemia; however, clinical application of IPC for ischemic brain and spinal diseases is difficult because they cannot be predicted. In addition, one drawback of preconditioning stimuli is that they are also capable of producing injury with only minor changes to their intensity or duration. Numerous methods to induce ischemic tolerance have been discovered that vary in their timing and the site at which short-term ischemia occurs. These methods include ischemic postconditioning (IPoC), remote ischemic preconditioning (RIPC), remote ischemic perconditioning (RIPerC) and remote ischemic postconditioning (RIPoC), which has had a great impact on clinical approaches to treatment of ischemic brain and spinal cord injury. Especially RIPerC and RIPoC to induce spinal cord tolerance are considered clinically useful, however the evidence supporting these methods is currently insufficient; further experimental or clinical research in this area is thus necessary.

  4. Focalized contractile impairment at hypertrophied myocardium proven in consideration of wall stress in patients with hypertrophic cardiomyopathy

    International Nuclear Information System (INIS)

    Yamazaki, Tadashi; Suzuki, Jun-ichi; Shimamoto, Ryoichi; Tsuji, Taeko; Ohmoto, Yuki; Toyo-oka, Teruhiko; Omata, Masao; Ohtomo, Kuni; Nagai, Ryozo

    2006-01-01

    In hypertrophic cardiomyopathy (HCM) a hyperkinetic state is sometimes observed in spite of impaired systolic function in the hypertrophied myocardium. The aim of the present study was to determine the mechanism of this paradox. Seventeen patients with HCM and 10 normal subjects underwent cine magnetic resonance (MR) imaging to measure percent systolic wall thickening and percent fractional shortening. The ratio of systolic radial wall stress of the LV at the hypertrophied myocardium over that at the nonhypertrophied myocardium was evaluated to describe the focal advantageous condition for wall thickening. The ratio was 0.66±0.36 at the start of contraction and 0.78±0.31 at early-systole, indicating consistently smaller radial wall stress at the hypertrophied myocardium. Although the condition for contraction was favorable (a ratio less than 1.00), percent systolic wall thickening at the hypertrophied myocardium (23.0±11.8%) was smaller than that at the nonhypertrophied myocardium (70.5±32.3%). Smaller end-diastolic dimension (HCM group; 45.2±4.2 mm, reference group; 48.9±4.1 mm, P=0.04) with a statistically identical value of systolic decrease in intraventricular dimension (HCM group; 19.7±3.9 mm, reference group; 18.9±3.2 mm, P=0.60) yielded high percent fractional shortening in patients with HCM (43.5±7.6%). Although contractile impairment was proven at the hypertrophied region with low radial wall stress in the HCM group, the smaller end-diastolic dimension in this group resulted in high percent fractional shortening. (author)

  5. Therapeutic angiogenesis in ischemic muscles after local injection of fragmented fibers with loaded traditional Chinese medicine

    Science.gov (United States)

    Li, Huiyan; Wan, Huiying; Xia, Tian; Chen, Maohua; Zhang, Yun; Luo, Xiaoming; Li, Xiaohong

    2015-07-01

    Therapeutic angiogenesis remains the most effective method to re-establish a proper blood flow in ischemic tissues. There is a great clinical need to identify an injectable format to achieve a well accumulation following local administration and a sustained delivery of biological factors at the ischemic sites. In the current study, fragmented nanofibers with loaded traditional Chinese medicines, astragaloside IV (AT), the main active ingredient of astragalus, and ferulic acid (FA), the main ingredient of angelica, were proposed to promote the microvessel formation after intramuscular injection into ischemic hindlimbs. Fragmented fibers with average lengths of 5 (FF-5), 20 (FF-20) and 80 μm (FF-80) were constructed by the cryocutting of aligned electrospun fibers. Their dispersion in sodium alginate solution (0.2%) indicated good injectability. After injection into the quadriceps muscles of the hindlimbs, FF-20 and FF-80 fiber fragments showed higher tissue retentions than FF-5, and around 90% of the injected doses were determined after 7 days. On a hindlimb ischemia model established by ligating the femoral arteries, intramuscular injection of the mixtures of FA-loaded and AT-loaded FF-20 fiber fragments substantially reduced the muscle degeneration with minimal fibrosis formation, significantly enhanced the neovessel formation and hindlimb perfusion in the ischemic tissues, and efficiently promoted the limb salvage with few limb losses. Along with the easy manipulation and lower invasiveness for in vivo administration, fragmented fibers should become potential drug carriers for disease treatment, wound recovery and tissue repair after local injection.

  6. Minimal quantization and confinement

    International Nuclear Information System (INIS)

    Ilieva, N.P.; Kalinowskij, Yu.L.; Nguyen Suan Han; Pervushin, V.N.

    1987-01-01

    A ''minimal'' version of the Hamiltonian quantization based on the explicit solution of the Gauss equation and on the gauge-invariance principle is considered. By the example of the one-particle Green function we show that the requirement for gauge invariance leads to relativistic covariance of the theory and to more proper definition of the Faddeev - Popov integral that does not depend on the gauge choice. The ''minimal'' quantization is applied to consider the gauge-ambiguity problem and a new topological mechanism of confinement

  7. Minimal Composite Inflation

    DEFF Research Database (Denmark)

    Channuie, Phongpichit; Jark Joergensen, Jakob; Sannino, Francesco

    2011-01-01

    We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful inflation via non-minimal coupling to gravity, and that the u......We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful inflation via non-minimal coupling to gravity...

  8. Minimalism and Speakers’ Intuitions

    Directory of Open Access Journals (Sweden)

    Matías Gariazzo

    2011-08-01

    Full Text Available Minimalism proposes a semantics that does not account for speakers’ intuitions about the truth conditions of a range of sentences or utterances. Thus, a challenge for this view is to offer an explanation of how its assignment of semantic contents to these sentences is grounded in their use. Such an account was mainly offered by Soames, but also suggested by Cappelen and Lepore. The article criticizes this explanation by presenting four kinds of counterexamples to it, and arrives at the conclusion that minimalism has not successfully answered the above-mentioned challenge.

  9. Minimal open strings

    International Nuclear Information System (INIS)

    Hosomichi, Kazuo

    2008-01-01

    We study FZZT-branes and open string amplitudes in (p, q) minimal string theory. We focus on the simplest boundary changing operators in two-matrix models, and identify the corresponding operators in worldsheet theory through the comparison of amplitudes. Along the way, we find a novel linear relation among FZZT boundary states in minimal string theory. We also show that the boundary ground ring is realized on physical open string operators in a very simple manner, and discuss its use for perturbative computation of higher open string amplitudes.

  10. Manifestation of automaticity in the pulmonary-vein myocardium of rats with abdominal aorto-venocaval shunt

    Directory of Open Access Journals (Sweden)

    Shogo Hamaguchi

    2015-08-01

    Full Text Available Effect of abdominal aorto-venocaval shunt (AVS on the automaticity of the pulmonary-vein myocardium was studied in the rat. Spontaneous electrical activity was observed in one third of the isolated pulmonary-vein preparations from the AVS rats, but scarcely in those from sham-operated rats; the activity was induced by tertiapin and suppressed by carbachol or chelation of intracellular Ca2+. The evoked action potentials in AVS rats had less negative resting membrane potential and longer action potential duration than those in sham-operated rats. These results suggest that the automaticity of the rat pulmonary-vein myocardium is manifested under chronic volume overload.

  11. Arteriosclerotic changes in the myocardium, lung, and kidney in dogs with chronic congestive heart failure and myxomatous mitral valve disease

    DEFF Research Database (Denmark)

    Falk, Bo Torkel; Jönsson, Lennart; Olsen, Lisbeth Høier

    2006-01-01

    Background: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. Methods: Twenty-one dogs with naturally occurring congestive heart failure and 21 age......-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta...... and pulmonary artery. Results: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (Pdogs. However...

  12. Infection in the ischemic lower extremity.

    Science.gov (United States)

    Fry, D E; Marek, J M; Langsfeld, M

    1998-06-01

    Infections in the lower extremity of the patient with ischemia can cover a broad spectrum of different diseases. An understanding of the particular pathophysiologic circumstances in the ischemic extremity can be of great value in understanding the natural history of the disease and the potential complications that may occur. Optimizing blood flow to the extremity by using revascularization techniques is important for any patient with an ischemic lower extremity complicated by infection or ulceration. Infections in the ischemic lower extremity require local débridement and systemic antibiotics. For severe infections, such as necrotizing fasciitis or the fetid foot, more extensive local débridement and even amputation may be required. Fundamentals of managing prosthetic graft infection require removing the infected prosthesis, local wound débridement, and systemic antibiotics while attempting to preserve viability of the lower extremity using autogenous graft reconstruction.

  13. Minimizing infarct size. Annual scientific report, 1 Jul 1975--15 Apr 1976

    International Nuclear Information System (INIS)

    Braunwald, E.

    1976-01-01

    Several goals were achieved during this period of 9 months, both in the experimental laboratory and in patients with acute myocardial infarction. (1) A study of the effects of aprotinin administration on myocardial ischemic injury, subsequent necrosis and collateral blood flow following acute coronary artery occlusion was carried out to completion. (2) A study of the effect of cobra venom factor on myocardial necrosis was completed and the factors responsible for its action were examined. (3) A comparison was made of the effects of nitroglycerin and nitroprusside on ischemic injury and regional myocardial blood flow in patients with acute myocardial infarction and in dogs with coronary occlusions. (4) A method of direct measurement of infarct size in the rat was developed. It consists of occlusion of the main left coronary artery and the histologic quantification of the infarct at 48 hours and 3 weeks later by serial histologic sections or alternatively by measuring total left ventricular myocardial creative phosphokinase activity. (5) New electrocardiographic methods have been developed in order to evaluate atraumatically the extent of myocardial infarction in patients. (6) Intravenous injection of (113)mIn-ENTMP and (99m)TcENTMP in dogs following coronary artery occlusion permitted a sequential double labeling of the damaged myocardium. (7) Since hyaluronidase is a very effective drug in reducing myocardial damage both in the experimental animal and in patients with acute myocardial infarction, a study was carried out to ascertain its effects on collateral flow

  14. Analysis of the relationship cost-effectiveness of the myocardial gammagraphy studies and the impact to the total expenditure by diagnostic of ischemic cardiopathy

    International Nuclear Information System (INIS)

    Valenzuela F, A.G.; Perez C, J.P.; Arreola O, H.; Valenzuela F, A.A.; Soto M, H.; Arguero S, R.

    2005-01-01

    Recent advances in pharmacology, diagnostic and invasive procedures provide a series of modalities that diminish the morbidity and increase the long term survival in the patients that have suffered a heart attack to myocardium. The stratification by risk is an essential element for the handling of the survivors of heart attack to myocardium. In their attention it is looked for to optimize the therapeutic benefit, to diminish the unnecessary diagnostic and therapeutic procedures and to improve the efficiency. For example, a coronariography in sick with heart attack to myocardium it is not cost-effective if not is clinically suitable. Of there that from the institutional point of view, this is, of the Mexican Institute of the Public Health, they are required of appropriate reference approaches and counter reference to grant to the sick person, the best service that is the one in this case the diagnostic and the handling of the ischemic cardiopathy with the smallest waste of resources. The estimation of the annual survival is the base of the stratification, it constitutes the angular stone of the early handling of the heart attack to myocardium. The goal for the clinical would be to identify patients with intermediate risk, since, this risk makes them candidates to therapy interventionist. As long as those with low risk won't require intervention. This would allow the decrease of rates by revenues of heart attack to myocardium, and therefore to diminish the hospital staying rates. The Nuclear Cardiology (myocardial gammagraphy) it is not the only invasive method available to evaluate the myocardial perfusion in sick in who coronary illness is suspected. When the myocardial gammagraphy is carried out in appropriate population, the cost it diminishes because it restricts the necessity of additional invasive evaluations. This because the nuclear cardiology has predictive value so much for the mortality like to detect myocardial viability. Based on these probabilities

  15. Minimal model holography

    International Nuclear Information System (INIS)

    Gaberdiel, Matthias R; Gopakumar, Rajesh

    2013-01-01

    We review the duality relating 2D W N minimal model conformal field theories, in a large-N ’t Hooft like limit, to higher spin gravitational theories on AdS 3 . This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’. (review)

  16. Minimal constrained supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Cribiori, N. [Dipartimento di Fisica e Astronomia “Galileo Galilei”, Università di Padova, Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova, Via Marzolo 8, 35131 Padova (Italy); Dall' Agata, G., E-mail: dallagat@pd.infn.it [Dipartimento di Fisica e Astronomia “Galileo Galilei”, Università di Padova, Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova, Via Marzolo 8, 35131 Padova (Italy); Farakos, F. [Dipartimento di Fisica e Astronomia “Galileo Galilei”, Università di Padova, Via Marzolo 8, 35131 Padova (Italy); INFN, Sezione di Padova, Via Marzolo 8, 35131 Padova (Italy); Porrati, M. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)

    2017-01-10

    We describe minimal supergravity models where supersymmetry is non-linearly realized via constrained superfields. We show that the resulting actions differ from the so called “de Sitter” supergravities because we consider constraints eliminating directly the auxiliary fields of the gravity multiplet.

  17. Hazardous waste minimization

    International Nuclear Information System (INIS)

    Freeman, H.

    1990-01-01

    This book presents an overview of waste minimization. Covers applications of technology to waste reduction, techniques for implementing programs, incorporation of programs into R and D, strategies for private industry and the public sector, and case studies of programs already in effect

  18. Minimally invasive distal pancreatectomy

    NARCIS (Netherlands)

    Røsok, Bård I.; de Rooij, Thijs; van Hilst, Jony; Diener, Markus K.; Allen, Peter J.; Vollmer, Charles M.; Kooby, David A.; Shrikhande, Shailesh V.; Asbun, Horacio J.; Barkun, Jeffrey; Besselink, Marc G.; Boggi, Ugo; Conlon, Kevin; Han, Ho Seong; Hansen, Paul; Kendrick, Michael L.; Kooby, David; Montagnini, Andre L.; Palanivelu, Chinnasamy; Wakabayashi, Go; Zeh, Herbert J.

    2017-01-01

    The first International conference on Minimally Invasive Pancreas Resection was arranged in conjunction with the annual meeting of the International Hepato-Pancreato-Biliary Association (IHPBA), in Sao Paulo, Brazil on April 19th 2016. The presented evidence and outcomes resulting from the session

  19. Minimal DBM Substraction

    DEFF Research Database (Denmark)

    David, Alexandre; Håkansson, John; G. Larsen, Kim

    In this paper we present an algorithm to compute DBM substractions with a guaranteed minimal number of splits and disjoint DBMs to avoid any redundance. The substraction is one of the few operations that result in a non-convex zone, and thus, requires splitting. It is of prime importance to reduce...

  20. Minimal constrained supergravity

    Directory of Open Access Journals (Sweden)

    N. Cribiori

    2017-01-01

    Full Text Available We describe minimal supergravity models where supersymmetry is non-linearly realized via constrained superfields. We show that the resulting actions differ from the so called “de Sitter” supergravities because we consider constraints eliminating directly the auxiliary fields of the gravity multiplet.

  1. Minimal constrained supergravity

    International Nuclear Information System (INIS)

    Cribiori, N.; Dall'Agata, G.; Farakos, F.; Porrati, M.

    2017-01-01

    We describe minimal supergravity models where supersymmetry is non-linearly realized via constrained superfields. We show that the resulting actions differ from the so called “de Sitter” supergravities because we consider constraints eliminating directly the auxiliary fields of the gravity multiplet.

  2. Drug Delivery to the Ischemic Brain

    Science.gov (United States)

    Thompson, Brandon J.; Ronaldson, Patrick T.

    2014-01-01

    Cerebral ischemia occurs when blood flow to the brain is insufficient to meet metabolic demand. This can result from cerebral artery occlusion that interrupts blood flow, limits CNS supply of oxygen and glucose, and causes an infarction/ischemic stroke. Ischemia initiates a cascade of molecular events inneurons and cerebrovascular endothelial cells including energy depletion, dissipation of ion gradients, calcium overload, excitotoxicity, oxidative stress, and accumulation of ions and fluid. Blood-brain barrier (BBB) disruption is associated with cerebral ischemia and leads to vasogenic edema, a primary cause of stroke-associated mortality. To date, only a single drug has received US Food and Drug Administration (FDA) approval for acute ischemic stroke treatment, recombinant tissue plasminogen activator (rt-PA). While rt-PA therapy restores perfusion to ischemic brain, considerable tissue damage occurs when cerebral blood flow is re-established. Therefore, there is a critical need for novel therapeutic approaches that can “rescue” salvageable brain tissue and/or protect BBB integrity during ischemic stroke. One class of drugs that may enable neural cell rescue following cerebral ischemia/reperfusion injury is the HMG-CoA reductase inhibitors (i.e., statins). Understanding potential CNS drug delivery pathways for statins is critical to their utility in ischemic stroke. Here, we review molecular pathways associated with cerebral ischemia and novel approaches for delivering drugs to treat ischemic disease. Specifically, we discuss utility of endogenous BBB drug uptake transporters such as organic anion transporting polypeptides (OATPs/Oatps) and nanotechnology-based carriers for optimization of CNS drug delivery. Overall, this chapter highlights state-of-the-art technologies that may improve pharmacotherapy of cerebral ischemia. PMID:25307217

  3. Impaired mitochondrial function in chronically ischemic human heart

    DEFF Research Database (Denmark)

    Stride, Nis Ottesen; Larsen, Steen; Hey-Mogensen, Martin

    2013-01-01

    , and finally to assess myocardial antioxidant levels. Mitochondrial respiration in biopsies from ischemic and nonischemic regions from the left ventricle of the same heart was compared in nine human subjects. Maximal oxidative phosphorylation capacity in fresh muscle fibers was lower in ischemic compared.......05), and the levels of antioxidant protein expression was lower. Diminished mitochondrial respiration capacity and excessive ROS production demonstrate an impaired mitochondrial function in ischemic human heart muscle. No chronic ischemic preconditioning effect was found....

  4. Polymorphisms in apolipoprotein B and risk of ischemic stroke

    DEFF Research Database (Denmark)

    Benn, Marianne; Nordestgaard, Børge G; Jensen, Jan Skov

    2007-01-01

    Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown.......Apolipoprotein B levels associate with risk of ischemic stroke. APOB polymorphisms may influence levels of apolipoprotein B and low-density lipoprotein (LDL), but whether they associate with risk of ischemic stroke is unknown....

  5. [Nonfasting triglycerides and risk of ischemic stroke--secondary publication

    DEFF Research Database (Denmark)

    Freiberg, J.J.; Tybjaerg-Hansen, A.; Jensen, J.S.

    2009-01-01

    The role of triglycerides in the risk of ischemic stroke remains controversial. We tested the hypothesis that increased levels of nonfasting triglycerides are associated with ischemic stroke in the general population. Men with a nonfasting triglyceride level 5 mmol/l had a multivariable, adjusted...... hazard ratio for ischemic stroke of 2.5 (95% confidence interval: 1.3-4.8) compared with men with a nonfasting triglyceride level triglycerides is associated with risk of ischemic stroke Udgivelsesdato...

  6. Ischemic stroke destabilizes circadian rhythms

    Directory of Open Access Journals (Sweden)

    Borjigin Jimo

    2008-10-01

    Full Text Available Abstract Background The central circadian pacemaker is a remarkably robust regulator of daily rhythmic variations of cardiovascular, endocrine, and neural physiology. Environmental lighting conditions are powerful modulators of circadian rhythms, but regulation of circadian rhythms by disease states is less clear. Here, we examine the effect of ischemic stroke on circadian rhythms in rats using high-resolution pineal microdialysis. Methods Rats were housed in LD 12:12 h conditions and monitored by pineal microdialysis to determine baseline melatonin timing profiles. After demonstration that the circadian expression of melatonin was at steady state, rats were subjected to experimental stroke using two-hour intralumenal filament occlusion of the middle cerebral artery. The animals were returned to their cages, and melatonin monitoring was resumed. The timing of onset, offset, and duration of melatonin secretion were calculated before and after stroke to determine changes in circadian rhythms of melatonin secretion. At the end of the monitoring period, brains were analyzed to determine infarct volume. Results Rats demonstrated immediate shifts in melatonin timing after stroke. We observed a broad range of perturbations in melatonin timing in subsequent days, with rats exhibiting onset/offset patterns which included: advance/advance, advance/delay, delay/advance, and delay/delay. Melatonin rhythms displayed prolonged instability several days after stroke, with a majority of rats showing a day-to-day alternation between advance and delay in melatonin onset and duration. Duration of melatonin secretion changed in response to stroke, and this change was strongly determined by the shift in melatonin onset time. There was no correlation between infarct size and the direction or amplitude of melatonin phase shifting. Conclusion This is the first demonstration that stroke induces immediate changes in the timing of pineal melatonin secretion, indicating

  7. Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells Relieve Acute Myocardial Ischemic Injury

    Directory of Open Access Journals (Sweden)

    Yuanyuan Zhao

    2015-01-01

    Full Text Available This study is aimed at investigating whether human umbilical cord mesenchymal stem cell- (hucMSC- derived exosomes (hucMSC-exosomes have a protective effect on acute myocardial infarction (AMI. Exosomes were characterized under transmission electron microscopy and the particles of exosomes were further examined through nanoparticle tracking analysis. Exosomes (400 μg protein were intravenously administrated immediately following ligation of the left anterior descending (LAD coronary artery in rats. Cardiac function was evaluated by echocardiography and apoptotic cells were counted using TUNEL staining. The cardiac fibrosis was assessed using Masson’s trichrome staining. The Ki67 positive cells in ischemic myocardium were determined using immunohistochemistry. The effect of hucMSC-exosomes on blood vessel formation was evaluated through tube formation and migration of human umbilical vein endothelial cells (EA.hy926 cells. The results indicated that ligation of the LAD coronary artery reduced cardiac function and induced cardiomyocyte apoptosis. Administration of hucMSC-exosomes significantly improved cardiac systolic function and reduced cardiac fibrosis. Moreover, hucMSC-exosomes protected myocardial cells from apoptosis and promoted the tube formation and migration of EA.hy926 cells. It is concluded that hucMSC-exosomes improved cardiac systolic function by protecting myocardial cells from apoptosis and promoting angiogenesis. These effects of hucMSC-exosomes might be associated with regulating the expression of Bcl-2 family.

  8. Neuregulin-1/erbB-activation improves cardiac function and survival in models of ischemic, dilated, and viral cardiomyopathy.

    Science.gov (United States)

    Liu, Xifu; Gu, Xinhua; Li, Zhaoming; Li, Xinyan; Li, Hui; Chang, Jianjie; Chen, Ping; Jin, Jing; Xi, Bing; Chen, Denghong; Lai, Donna; Graham, Robert M; Zhou, Mingdong

    2006-10-03

    We evaluated the therapeutic potential of a recombinant 61-residue neuregulin-1 (beta2a isoform) receptor-active peptide (rhNRG-1) in multiple animal models of heart disease. Activation of the erbB family of receptor tyrosine kinases by rhNRG-1 could provide a treatment option for heart failure, because neuregulin-stimulated erbB2/erbB4 heterodimerization is not only critical for myocardium formation in early heart development but prevents severe dysfunction of the adult heart and premature death. Disabled erbB-signaling is also implicated in the transition from compensatory hypertrophy to failure, whereas erbB receptor-activation promotes myocardial cell growth and survival and protects against anthracycline-induced cardiomyopathy. rhNRG-1 was administered IV to animal models of ischemic, dilated, and viral cardiomyopathy, and cardiac function and survival were evaluated. Short-term intravenous administration of rhNRG-1 to normal dogs and rats did not alter hemodynamics or cardiac contractility. In contrast, rhNRG-1 improved cardiac performance, attenuated pathological changes, and prolonged survival in rodent models of ischemic, dilated, and viral cardiomyopathy, with the survival benefits in the ischemic model being additive to those of angiotensin-converting enzyme inhibitor therapy. In addition, despite continued pacing, rhNRG-1 produced global improvements in cardiac function in a canine model of pacing-induced heart failure. These beneficial effects make rhNRG-1 promising as a broad-spectrum therapeutic for the treatment of heart failure due to a variety of common cardiac diseases.

  9. Neonatal ischemic brain injury: what every radiologist needs to know

    International Nuclear Information System (INIS)

    Badve, Chaitra A.; Khanna, Paritosh C.; Ishak, Gisele E.

    2012-01-01

    We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested. (orig.)

  10. The Neuroprotective Effect Of Electro-Acupuncture Against Ischemic ...

    African Journals Online (AJOL)

    The Neuroprotective Effect Of Electro-Acupuncture Against Ischemic Stroke In Animal Model: A Review. ... Conclusion: An awareness of the benefits of acupuncture might lead more patients into accepting acupuncture therapy for the management of patients with ischemic stroke and patients with high risk of ischemic stroke.

  11. Distinct patterns of constitutive phosphodiesterase activity in mouse sinoatrial node and atrial myocardium.

    Directory of Open Access Journals (Sweden)

    Rui Hua

    Full Text Available Phosphodiesterases (PDEs are critical regulators of cyclic nucleotides in the heart. In ventricular myocytes, the L-type Ca(2+ current (I(Ca,L is a major target of regulation by PDEs, particularly members of the PDE2, PDE3 and PDE4 families. Conversely, much less is known about the roles of PDE2, PDE3 and PDE4 in the regulation of action potential (AP properties and I(Ca,L in the sinoatrial node (SAN and the atrial myocardium, especially in mice. Thus, the purpose of our study was to measure the effects of global PDE inhibition with Isobutyl-1-methylxanthine (IBMX and selective inhibitors of PDE2, PDE3 and PDE4 on AP properties in isolated mouse SAN and right atrial myocytes. We also measured the effects of these inhibitors on I(Ca,L in SAN and atrial myocytes in comparison to ventricular myocytes. Our data demonstrate that IBMX markedly increases spontaneous AP frequency in SAN myocytes and AP duration in atrial myocytes. Spontaneous AP firing in SAN myocytes was also increased by the PDE2 inhibitor erythro-9-[2-hydroxy-3-nonyl] adenine (EHNA, the PDE3 inhibitor milrinone (Mil and the PDE4 inhibitor rolipram (Rol. In contrast, atrial AP duration was increased by EHNA and Rol, but not by Mil. IBMX also potently, and similarly, increased I(Ca,L in SAN, atrial and ventricular myocytes; however, important differences emerged in terms of which inhibitors could modulate I(Ca,L in each myocyte type. Consistent with our AP measurements, EHNA, Mil and Rol each increased I(Ca,L in SAN myocytes. Also, EHNA and Rol, but not Mil, increased atrial I(Ca,L. In complete contrast, no selective PDE inhibitors increased I(Ca,L in ventricular myocytes when given alone. Thus, our data show that the effects of selective PDE2, PDE3 and PDE4 inhibitors are distinct in the different regions of the myocardium indicating important differences in how each PDE family constitutively regulates ion channel function in the SAN, atrial and ventricular myocardium.

  12. Stretch-dependent slow force response in isolated rabbit myocardium is Na+ dependent.

    Science.gov (United States)

    von Lewinski, Dirk; Stumme, Burkhard; Maier, Lars S; Luers, Claus; Bers, Donald M; Pieske, Burkert

    2003-03-15

    Stretch induces functional and trophic effects in mammalian myocardium via various signal transduction pathways. We tested stretch signal transduction on immediate and slow force response (SFR) in rabbit myocardium. Experiments were performed in isolated right ventricular muscles from adult rabbit hearts (37 degrees C, 1 Hz stimulation rate, bicarbonate-buffer). Muscles were rapidly stretched from 88% of optimal length (L88) to near optimal length (L98) for functional analysis. The resulting immediate and slow increases in twitch force (first phase and SFR, respectively) were assessed at reduced [Na+]o or without and with blockade of stretch activated ion channels (SACs), angiotensin-II (AT1) receptors, endothelin-A (ET(A)) receptors, Na+/H+-exchange (NHE1), reverse mode Na+/Ca2+-exchange (NCX), or Na+/K+-ATPase. The effects of stretch on sarcoplasmic reticulum Ca2+-load were characterized using rapid cooling contractures (RCCs). Intracellular pH was measured in BCECF-AM loaded muscles, and action potential duration (APD) was assessed using floating electrodes. On average, force increased to 216+/-8% of the pre-stretch value during the immediate phase, followed by a further increase to 273+/-10% during the SFR (n=81). RCCs significantly increased during SFR, whereas pH and APD did not change. Neither inhibition of SACs, AT1, or ET(A) receptors affected the stretch-dependent immediate phase nor SFR. In contrast, SFR was reduced by NHE inhibition and almost completely abolished by reduced [Na+]o or inhibition of reverse-mode NCX, whereas increased SFR was seen after raising [Na+]i by Na+/K+-ATPase inhibition. The data demonstrate the existence of a delayed, Na+- and Ca2+-dependent but pH and APD independent SFR to stretch in rabbit myocardium. This inotropic response appears to be independent of autocrine/paracrine AT1 or ET(A) receptor activation, but mediated through stretch-induced activation of NHE and reverse mode NCX.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  14. Association of Childhood Body Mass Index and Change in Body Mass Index With First Adult Ischemic Stroke.

    Science.gov (United States)

    Gjærde, Line K; Gamborg, Michael; Ängquist, Lars; Truelsen, Thomas C; Sørensen, Thorkild I A; Baker, Jennifer L

    2017-11-01

    The incidence of ischemic stroke among young adults is rising and is potentially due to an increase in stroke risk factors occurring at younger ages, such as obesity. To investigate whether childhood body mass index (BMI) and change in BMI are associated with adult ischemic stroke and to assess whether the associations are age dependent or influenced by birth weight. This investigation was a population-based cohort study of schoolchildren born from 1930 to 1987, with follow-up through national health registers from 1977 to 2012 in Denmark. Participants were 307 677 individuals (8899 ischemic stroke cases) with measured weight and height at ages 7 to 13 years. The dates of the analysis were September 1, 2015, to May 27, 2016. Childhood BMI, change in BMI, and birth weight. Ischemic stroke events were divided into early (≤55 years) or late (>55 years) age at diagnosis. The study cohort comprised 307 677 participants (approximately 49% female and 51% male). During the study period, 3529 women and 5370 men experienced an ischemic stroke. At all ages from 7 to 13 years, an above-average BMI z score was positively associated with early ischemic stroke. At age 13 years, a BMI z score of 1 was associated with hazard ratios (HRs) of 1.26 (95% CI, 1.11-1.43) in women and 1.21 (95% CI, 1.10-1.33) in men. No significant associations were found for below-average BMI z scores. Among children with above-average BMI z scores at age 7 years, a score increase of 0.5 from ages 7 to 13 years was positively associated with early ischemic stroke in women (HR, 1.10; 95% CI, 1.01-1.20) and in men (HR, 1.08; 95% CI, 1.00-1.16). Similarly, among children with below-average BMI z scores at age 7 years, a score increase of 0.5 from ages 7 to 13 years was positively associated with early ischemic stroke in women (HR, 1.14; 95% CI, 1.06-1.23) and in men (HR, 1.10; 95% CI, 1.04-1.18). Adjusting for birth weight minimally affected the associations. Independent of birth weight, above

  15. Minimal abdominal incisions

    Directory of Open Access Journals (Sweden)

    João Carlos Magi

    2017-04-01

    Full Text Available Minimally invasive procedures aim to resolve the disease with minimal trauma to the body, resulting in a rapid return to activities and in reductions of infection, complications, costs and pain. Minimally incised laparotomy, sometimes referred to as minilaparotomy, is an example of such minimally invasive procedures. The aim of this study is to demonstrate the feasibility and utility of laparotomy with minimal incision based on the literature and exemplifying with a case. The case in question describes reconstruction of the intestinal transit with the use of this incision. Male, young, HIV-positive patient in a late postoperative of ileotiflectomy, terminal ileostomy and closing of the ascending colon by an acute perforating abdomen, due to ileocolonic tuberculosis. The barium enema showed a proximal stump of the right colon near the ileostomy. The access to the cavity was made through the orifice resulting from the release of the stoma, with a lateral-lateral ileo-colonic anastomosis with a 25 mm circular stapler and manual closure of the ileal stump. These surgeries require their own tactics, such as rigor in the lysis of adhesions, tissue traction, and hemostasis, in addition to requiring surgeon dexterity – but without the need for investments in technology; moreover, the learning curve is reported as being lower than that for videolaparoscopy. Laparotomy with minimal incision should be considered as a valid and viable option in the treatment of surgical conditions. Resumo: Procedimentos minimamente invasivos visam resolver a doença com o mínimo de trauma ao organismo, resultando em retorno rápido às atividades, reduções nas infecções, complicações, custos e na dor. A laparotomia com incisão mínima, algumas vezes referida como minilaparotomia, é um exemplo desses procedimentos minimamente invasivos. O objetivo deste trabalho é demonstrar a viabilidade e utilidade das laparotomias com incisão mínima com base na literatura e

  16. Minimal Walking Technicolor

    DEFF Research Database (Denmark)

    Foadi, Roshan; Frandsen, Mads Toudal; A. Ryttov, T.

    2007-01-01

    Different theoretical and phenomenological aspects of the Minimal and Nonminimal Walking Technicolor theories have recently been studied. The goal here is to make the models ready for collider phenomenology. We do this by constructing the low energy effective theory containing scalars......, pseudoscalars, vector mesons and other fields predicted by the minimal walking theory. We construct their self-interactions and interactions with standard model fields. Using the Weinberg sum rules, opportunely modified to take into account the walking behavior of the underlying gauge theory, we find...... interesting relations for the spin-one spectrum. We derive the electroweak parameters using the newly constructed effective theory and compare the results with the underlying gauge theory. Our analysis is sufficiently general such that the resulting model can be used to represent a generic walking technicolor...

  17. Nitrate administration increases blood flow in dysfunctional but viable myocardium, leading to improved assessment of myocardial viability : A PET study

    NARCIS (Netherlands)

    Slart, Riemer H. J. A.; Agool, Ali; van Veldhuisen, Dirk J.; Dierckx, Rudi A.; Bax, Jeroen J.

    SPECT with Tc-99m-labeled agents is better able to detect viability after nitrate administration. Nitrates induce vasoclilation and may increase blood flow to severely hypoperfused but viable myocardium, thereby enhancing tracer delivery and improving the detection of viability. Quantitative data on

  18. Volume of myocardium perfused by coronary artery branches as estimated from 3D micro-CT images of rat hearts

    Science.gov (United States)

    Lund, Patricia E.; Naessens, Lauren C.; Seaman, Catherine A.; Reyes, Denise A.; Ritman, Erik L.

    2000-04-01

    Average myocardial perfusion is remarkably consistent throughout the heart wall under resting conditions and the velocity of blood flow is fairly reproducible from artery to artery. Based on these observations, and the fact that flow through an artery is the product of arterial cross-sectional area and blood flow velocity, we would expect the volume of myocardium perfused to be proportional to the cross-sectional area of the coronary artery perfusing that volume of myocardium. This relationship has been confirmed by others in pigs, dogs and humans. To test the body size-dependence of this relationship we used the hearts from rats, 3 through 25 weeks of age. The coronary arteries were infused with radiopaque microfil polymer and the hearts scanned in a micro- CT scanner. Using these 3D images we measured the volume of myocardium and the arterial cross-sectional area of the artery that perfused that volume of myocardium. The average constant of proportionality was found to be 0.15 +/- 0.08 cm3/mm2. Our data showed no statistically different estimates of the constant of proportionality in the rat hearts of different ages nor between the left and right coronary arteries. This constant is smaller than that observed in large animals and humans, but this difference is consistent with the body mass-dependence on metabolic rate.

  19. Mitochondrial complex III defects contribute to inefficient respiration and ATP synthesis in the myocardium of Trypanosoma cruzi-infected mice.

    Science.gov (United States)

    Wen, Jian-Jun; Garg, Nisha Jain

    2010-01-01

    In this study, we conducted a thorough analysis of mitochondrial bioenergetic function as well as the biochemical and molecular factors that are deregulated and contribute to compromised adenosine triphosphate (ATP) production in the myocardium during Trypanosoma cruzi infection. We show that ADP-stimulated state 3 respiration and ATP synthesis supported by pyruvate/malate (provides electrons to complex I) and succinate (provides electrons to complex II) substrates were significantly decreased in left ventricular tissue and isolated cardiac mitochondria of infected mice. The decreased mitochondrial ATP synthesis in infected murine hearts was not a result of uncoupling between the electron-transport chain and oxidative phosphorylation and decreased availability of the intermediary metabolites (e.g., NADH). The observed decline in the activities of complex-I, -IV, and -V was not physiologically relevant and did not contribute to compromised respiration and ATP synthesis in infected myocardium. Instead, complex III activity was decreased above the threshold level and contributed to respiratory-chain inefficiency and the resulting decline in mitochondrial ATP synthesis in infected myocardium. The loss in complex III activity occurred as a consequence of cytochrome b depletion. Treatment of infected mice with phenyl-alpha-tert-butyl nitrone (PBN, antioxidant) was beneficial in preserving the mtDNA-encoded cytochrome b expression, and subsequently resulted in improved complex III activity, mitochondrial respiration, and ATP production in infected myocardium. Overall, we provide novel data on the mechanism(s) involved in cardiac bioenergetic inefficiency during T. cruzi infection.

  20. Experimental study of 31P MR spectroscopy in vitro canine myocardium

    International Nuclear Information System (INIS)

    Gao Fabao; Zhao Haitao; Suo Liping; Zhang Yushun; Fang Hong; Huang Zhilan

    1999-01-01

    Objective: To conduct a dynamic survey of the metabolism of high-energy phosphates in myocardium in order to define, the relationship between the changes in myocardial energy metabolism and the duration of ischemia. Methods: A dynamic survey of isolated heart of 8 dogs was done with the use of 31 P MRS. Results: Myocardial PCr level decreased rapidly after the heart was isolated and was reduced to zero in 2-3 hours. ATP level diminished progressively to its depletion at 6 hours following isolation. Conclusions: After the heart was isolated, the PCr level rapidly decreased and was reduced to zero in 2-3 hours whereas ATP was not depleted until 4-6 hours after isolation. The ATP level remained within normal limits as long as PCr had not been depleted

  1. Comparison of exercise and pharmacologic stress in myocardium perfusion imaging for CHD

    International Nuclear Information System (INIS)

    Li Zebo; Zheng Kangni; Cheng Xiaorui; Liu Hui; Cheng Yihai

    1995-01-01

    In order to provide a proper stress test, exercise, dipyridamole and ATP stress were compared. Three modalities were compared with respect to the detecting rate, methodology, hemodynamic and side effects. There are no significant differences in their ability of detecting coronary heart disease (CHD) (P>0.05). Exercise stress causes an increase in heart rate, blood pressure and myocardium oxygen consumption. Pharmacologic stress cause a slight increase in heart rate, but a decrease in blood pressure (P<0.01). Exercise stress is a basic method with good image quality, but it needs a special equipment. Pharmacologic stress is an easier, cheaper and safer method, particularly useful for patients unable to perform exercise test

  2. Isolated noncompaction of myocardium associated with calcification in the interventricular septum.

    Science.gov (United States)

    Nil, M; Mori, K; Yuasa, Y; Ichida, F

    2003-01-01

    We describe a 12-year-old male with isolated noncompaction of the myocardium and associated abnormal calcification in the basal interventricular septum, and we present a review of the literature. The patient has been healthy and free of symptoms. The electrocardiogram showed abnormal Q waves in III, V1, V2, and ST elevation in V1-V3. Exercise testing demonstrated ST depression in V4 and V5. Myocardial scintigraphic examination showed a regional reduction in iodine-1,2,3-beta-methyl-iodophenylpentadecanoic acid uptake in the basal interventricular septum. Since coronary angiography demonstrated normal coronary vessels and the trabeculations were not prominent in this region, we hypothesize that coronary microcirculatory dysfunction may cause subendocardial infarction associated with calcification in the same area.

  3. Effects of Ischemic Preconditioning of Different Intraoperative Ischemic Times of Vascularized Bone Graft Rabbit Models

    Directory of Open Access Journals (Sweden)

    Ahmad Sukari Halim

    2013-11-01

    Full Text Available BackgroundIschemic preconditioning has been shown to improve the outcomes of hypoxic tolerance of the heart, brain, lung, liver, jejunum, skin, and muscle tissues. However, to date, no report of ischemic preconditioning on vascularized bone grafts has been published.MethodsSixteen rabbits were divided into four groups with ischemic times of 2, 6, 14, and 18 hours. Half of the rabbits in each group underwent ischemic preconditioning. The osteomyocutaneous flaps consisted of the tibia bone, from which the overlying muscle and skin were raised. The technique of ischemic preconditioning involved applying a vascular clamp to the pedicle for 3 cycles of 10 minutes each. The rabbits then underwent serial plain radiography and computed tomography imaging on the first, second, fourth, and sixth postoperative weeks. Following this, all of the rabbits were sacrificed and histological examinations were performed.ResultsThe results showed that for clinical analysis of the skin flaps and bone grafts, the preconditioned groups showed better survivability. In the plain radiographs, except for two non-preconditioned rabbits with intraoperative ischemic times of 6 hours, all began to show early callus formation at the fourth week. The computed tomography findings showed more callus formation in the preconditioned groups for all of the ischemic times except for the 18-hour group. The histological findings correlated with the radiological findings. There was no statistical significance in the difference between the two groups.ConclusionsIn conclusion, ischemic preconditioning improved the survivability of skin flaps and increased callus formation during the healing process of vascularized bone grafts.

  4. Occurrence and predictors of persistent impaired glucose tolerance after acute ischemic stroke or transient ischemic attack

    OpenAIRE

    Fonville, Susanne; Hertog, Heleen; Zandbergen, Adrienne; Koudstaal, Peter Jan; Lingsma, Hester

    2014-01-01

    textabstractBackground Impaired glucose tolerance is often present in patients with a transient ischemic attack (TIA) or ischemic stroke and doubles the risk of recurrent stroke. This impaired glucose tolerance can be transient, reflecting an acute stress response, or persistent, representing undiagnosed impaired glucose metabolism possibly requiring treatment. We aimed to assess the occurrence of persistent impaired glucose tolerance after a stroke or TIA and to develop a prediction model to...

  5. Constitutive activation of Nrf2 induces a stable reductive state in the mouse myocardium

    Directory of Open Access Journals (Sweden)

    Gobinath Shanmugam

    2017-08-01

    Full Text Available Redox homeostasis regulates key cellular signaling pathways in both physiology and pathology. The cell's antioxidant response provides a defense against oxidative stress and establishes a redox tone permissive for cell signaling. The molecular regulation of the well-known Keap1/Nrf2 system acts as sensor responding to changes in redox homeostasis and is poorly studied in the heart. Importantly, it is not yet known whether Nrf2 alone can serve as a master regulator of cellular redox homeostasis without compensation of the transcriptional regulation of antioxidant response element (ARE genes through alternate mechanisms. Here, we addressed this question using cardiac-specific transgenic expression at two different levels of constitutively active nuclear erythroid related factor 2 (caNrf2 functioning independently of Keap1. The caNrf2 mice showed augmentation of glutathione (GSH, the key regulator of the cellular thiol redox state. The Trans-AM assay for Nrf2-binding to the antioxidant response element (ARE showed a dose-dependent increase associated with upregulation of several major antioxidant genes and proteins. This was accompanied by a significant decrease in dihydroethidium staining and malondialdehyde (MDA in the caNrf2-TG mice myocardium. Interestingly, caNrf2 gene-dosage dependent redox changes were noted resulting in generation of a multi-stage model of pro-reductive and reductive conditions in the myocardium of TG-low and TG-high mice, respectively. These data clearly show that Nrf2 levels alone are capable of serving as the master regulator of the ARE. These models provide an important platform to investigate the impact of the Nrf2 system independent of the need to regulate the activity of Keap1 and the consequent exposure to pro-oxidants or electrophiles, which have numerous off-target effects.

  6. Hyperthyroidism causes mechanical insufficiency of myocardium with possibly increased SR Ca2+-ATPase activity.

    Science.gov (United States)

    Takeuchi, Koh; Minakawa, M; Otaki, M; Odagiri, S; Itoh, K; Murakami, A; Yaku, H; Kitamura, N

    2003-12-01

    Hyperthyroidism is known to affect multiple organ functions, and thyroid hormone has been known to improve myocardial function in a failing heart. The purpose of this study is to elucidate the functional and metabolic effects of thyroid hormone on myocardium in a rat model exposed to long-term excess thyroid hormone, particularly focusing on the SR Ca(2+)-ATPase (SERCA2) function. 3,5,3'-Triiodo-L-thyronine (T3), or the vehicle, was subcutaneously given for 4 weeks (T3 and control [C] group). Bolus I.V. Thapsigargin (TG) was used to test the SERCA2 function (C-TG and T3-TG) in Langendorff perfused heart. Myocardial functions such as LV-developed pressure (LVDP; mmHg), +/- dP/dt (mmHg/s), tau (ms), and oxygen consumption (MVO(2); ml/min/g wt) were measured. SERCA2 and GLUT4 protein level were also evaluated by Western immunoblotting. Left ventricle to body weight (LV/BW) ratio was significantly higher in the T3 group. Both negative dP/dt and tau were significantly decreased by TG. It is interesting that the decrement of negative dP/dt and tau attained by TG was significantly larger in the hyperthyroid group (T3-TG) than in a normal heart (C-TG). SERCA2 and GLUT4 protein levels were not significantly different between control and the T3 group. We conclude that prolonged exposure to thyroid hormone causes hypertrophy of the myocardium and an augmentation of the SR Ca(2+) ATPase activity. Care must be taken in hyperthyroid heart during the ischemia-reperfusion process where the SRECA2 function is inhibited.

  7. Characterization of the Structural and Functional Changes in the Myocardium Following Focal Ischemia-Reperfusion Injury

    Science.gov (United States)

    Ojha, Navdeep; Roy, Sashwati; Radtke, Jared; Simonetti, Orlando; Gnyawali, Surya; Zweier, Jay L.; Kuppusamy, Periannan; Sen, Chandan K.

    2015-01-01

    High resolution (11.7T) cardiac magnetic resonance imaging (MRI) and histological approaches have been employed in tandem to characterize the secondary damage suffered by the murine myocardium following the initial insult caused by ischemia-reperfusion (IR). IR induced changes in the myocardium were examined in five separate groups at the following time-points after IR: 1h, 1d, 3d, 7d and 14 d. Infarct volume increased from 1h to 1d post-IR. Over time, loss of myocardial function was observed to be associated with increased infarct volume and worsened regional wall motion. In the infarct region, IR caused a decrease in end-systolic thickness coupled with small changes in end-diastolic thickness, leading to massive wall thickening abnormalities. In addition, compromised wall thickening was also observed in left ventricular regions adjacent to the infarct region. A tight correlation (r2 = 0.86) between measured MRI and triphenyltetrazolium chloride (TTC) infarct volumes was noted. Our observation that until day 3 post-IR, the infarct size as measured by TTC staining and MRI were much larger than the myocyte-silent regions in trichrome or H&E stained sections is consistent with the literature and leads to the conclusion that at such early phase the infarct site contains structurally intact myocytes that are functionally compromised. Over time, such affected myocytes were noted to structurally disappear resulting in consistent infarct sizes obtained from MRI, TTC as well as trichrome and hematoxylin/eosin analyses on day 7 following IR. Myocardial remodeling following IR includes secondary myocyte death followed by loss of cardiac function over time. PMID:18375718

  8. Stereoselective handling of perhexiline: implications regarding accumulation within the human myocardium.

    Science.gov (United States)

    Chong, Cher-Rin; Drury, Nigel E; Licari, Giovanni; Frenneaux, Michael P; Horowitz, John D; Pagano, Domenico; Sallustio, Benedetta C

    2015-12-01

    Perhexiline is a prophylactic anti-ischaemic agent with weak calcium antagonist effect which has been increasingly utilised in the management of refractory angina. The metabolic clearance of perhexiline is modulated by CYP2D6 metaboliser status and stereoselectivity. The current study sought to (1) determine whether the acute accumulation of perhexiline in the myocardium is stereoselective and (2) investigate the relationship between duration of short-term therapy and the potential stereoselective effects of perhexiline within myocardium. Patients (n = 129) from the active arm of a randomised controlled trial of preoperative perhexiline in cardiac surgery were treated with oral perhexiline for a median of 9 days. Correlates of atrial and ventricular concentrations of enantiomers were sought via univariate followed by multivariate analyses. Myocardial uptake of both (+) and (-) perhexiline was greater in ventricles than in atria, and there was more rapid clearance of (-) than (+) perhexiline. The main determinants of atrial uptake of both (+) and (-) perhexiline were the plasma concentrations [(+) perhexiline: β = -0.256, p = 0.015; (-) perhexiline: β = -0.347, p = 0.001] and patients' age [(+) perhexiline: β = 0.300, p = 0.004; (-) perhexiline: β = 0.288, p = 0.005]. Atrial uptake of (+) enantiomer also varied directly with duration of therapy (β = 0.228, p = 0.025), while atrial uptake of (-) perhexiline varied inversely with simultaneous heart rate (β = -0.240, p = 0.015). (1) Uptake of both perhexiline enantiomers into atrium is greater with advanced age and displays evidence of both saturability and minor stereoselectivity. (2) Atrial uptake of (-) perhexiline may selectively modulate heart rate reduction.

  9. Miocárdio hibernante: uma realidade clínica Hibernant myocardium: a clinical reality

    Directory of Open Access Journals (Sweden)

    J.A. Marin-Neto

    1997-12-01

    Full Text Available O conceito da hibernação miocárdica implica a ocorrência de disfunção ventricular crônica, potencialmente reversível, causada por dissinergia regional, dependente de isquemia prolongada. Não tem fisiopatologia elucidada, em parte porque não existem modelos experimentais satisfatórios para seu estudo. Diversos métodos são capazes de demonstrar viabilidade miocárdica nas regiões que não exibem capacidade contrátil basal. O desmascaramento da hibernação nesses territórios pode ser feito mediante demonstração de reserva contrátil, de funcionamento normal da membrana celular, ou de metabolismo preservado. A correta identificação de miocárdio hibernante reveste-se de especial significado clínico, por suas implicações prognósticas quanto a intervenções de revascularização miocárdica, destinadas a reabilitar a função ventricular em muitos pacientes coronariopatas crônicos.Myocardial hibernation is believed to occur in ventricular dyssynergic regions chronically deprived of coronary flow enough to warrant the preservation of contractile function. Pathophysiology of this condition remains largely unclear, mainly because good experimental models for its study are still lacking. Various methods can be clinically employed to detect hibernation in patients with chronic ventricular dysfunction. These methods use the principle of unmasking contractile reserve, or are based on the demonstration of preserved membrane function or myocardium metabolism in the dyssynergic regions. The correct identification of viable hibernating myocardium is crucial in the process of deciding which coronary disease patients would potentially benefit from revascularization procedures.

  10. Gene Expression Networks in the Murine Pulmonary Myocardium Provide Insight into the Pathobiology of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Jordan K. Boutilier

    2017-09-01

    Full Text Available The pulmonary myocardium is a muscular coat surrounding the pulmonary and caval veins. Although its definitive physiological function is unknown, it may have a pathological role as the source of ectopic beats initiating atrial fibrillation. How the pulmonary myocardium gains pacemaker function is not clearly defined, although recent evidence indicates that changed transcriptional gene expression networks are at fault. The gene expression profile of this distinct cell type in situ was examined to investigate underlying molecular events that might contribute to atrial fibrillation. Via systems genetics, a whole-lung transcriptome data set from the BXD recombinant inbred mouse resource was analyzed, uncovering a pulmonary cardiomyocyte gene network of 24 transcripts, coordinately regulated by chromosome 1 and 2 loci. Promoter enrichment analysis and interrogation of publicly available ChIP-seq data suggested that transcription of this gene network may be regulated by the concerted activity of NKX2-5, serum response factor, myocyte enhancer factor 2, and also, at a post-transcriptional level, by RNA binding protein motif 20. Gene ontology terms indicate that this gene network overlaps with molecular markers of the stressed heart. Therefore, we propose that perturbed regulation of this gene network might lead to altered calcium handling, myocyte growth, and contractile force contributing to the aberrant electrophysiological properties observed in atrial fibrillation. We reveal novel molecular interactions and pathways representing possible therapeutic targets for atrial fibrillation. In addition, we highlight the utility of recombinant inbred mouse resources in detecting and characterizing gene expression networks of relatively small populations of cells that have a pathological significance.

  11. Quantitative shear wave imaging optical coherence tomography for noncontact mechanical characterization of myocardium

    Science.gov (United States)

    Wang, Shang; Lopez, Andrew L.; Morikawa, Yuka; Tao, Ge; Li, Jiasong; Larina, Irina V.; Martin, James F.; Larin, Kirill V.

    2015-03-01

    Optical coherence elastography (OCE) is an emerging low-coherence imaging technique that provides noninvasive assessment of tissue biomechanics with high spatial resolution. Among various OCE methods, the capability of quantitative measurement of tissue elasticity is of great importance for tissue characterization and pathology detection across different samples. Here we report a quantitative OCE technique, termed quantitative shear wave imaging optical coherence tomography (Q-SWI-OCT), which enables noncontact measurement of tissue Young's modulus based on the ultra-fast imaging of the shear wave propagation inside the sample. A focused air-puff device is used to interrogate the tissue with a low-pressure short-duration air stream that stimulates a localized displacement with the scale at micron level. The propagation of this tissue deformation in the form of shear wave is captured by a phase-sensitive OCT system running with the scan of the M-mode imaging over the path of the wave propagation. The temporal characteristics of the shear wave is quantified based on the cross-correlation of the tissue deformation profiles at all the measurement locations, and linear regression is utilized to fit the data plotted in the domain of time delay versus wave propagation distance. The wave group velocity is thus calculated, which results in the quantitative measurement of the Young's modulus. As the feasibility demonstration, experiments are performed on tissuemimicking phantoms with different agar concentrations and the quantified elasticity values with Q-SWI-OCT agree well with the uniaxial compression tests. For functional characterization of myocardium with this OCE technique, we perform our pilot experiments on ex vivo mouse cardiac muscle tissues with two studies, including 1) elasticity difference of cardiac muscle under relaxation and contract conditions and 2) mechanical heterogeneity of the heart introduced by the muscle fiber orientation. Our results suggest the

  12. Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes.

    Science.gov (United States)

    Perna, Robert; Temple, Jessica

    2015-01-01

    Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n = 172) or hemorrhagic stroke (n = 112) within the past six months and were involved in a postacute neurorehabilitation program. Participants completed three months of postacute neurorehabilitation and the Mayo Portland Adaptability Inventory-4 (MPAI-4) at admission and discharge. Admission MPAI-4 scores and level of functioning were comparable. Results. Group ANOVA comparisons show no significant group differences at admission or discharge or difference in change scores. Both groups showed considerably reduced levels of productivity/employment after discharge as compared to preinjury levels. Conclusions. Though the pathophysiology of these types of strokes is different, both ultimately result in ischemic injuries, possibly accounting for lack of findings of differences between groups. In the present study, participants in both groups experienced similar functional levels across all three MPAI-4 domains both at admission and discharge. Limitations of this study include a highly educated sample and few outcome measures.

  13. Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes

    Directory of Open Access Journals (Sweden)

    Robert Perna

    2015-01-01

    Full Text Available Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n=172 or hemorrhagic stroke (n=112 within the past six months and were involved in a postacute neurorehabilitation program. Participants completed three months of postacute neurorehabilitation and the Mayo Portland Adaptability Inventory-4 (MPAI-4 at admission and discharge. Admission MPAI-4 scores and level of functioning were comparable. Results. Group ANOVA comparisons show no significant group differences at admission or discharge or difference in change scores. Both groups showed considerably reduced levels of productivity/employment after discharge as compared to preinjury levels. Conclusions. Though the pathophysiology of these types of strokes is different, both ultimately result in ischemic injuries, possibly accounting for lack of findings of differences between groups. In the present study, participants in both groups experienced similar functional levels across all three MPAI-4 domains both at admission and discharge. Limitations of this study include a highly educated sample and few outcome measures.

  14. Ischemic Stroke during Pregnancy and Puerperium

    Directory of Open Access Journals (Sweden)

    Elisabetta Del Zotto

    2011-01-01

    Full Text Available Ischemic stroke during pregnancy and puerperium represents a rare occurrence but it could be a serious and stressful event for mothers, infants, and also families. Whenever it does occur, many concerns arise about the safety of the mother and the fetus in relation to common diagnostic tests and therapies leading to a more conservative approach. The physiological adaptations in the cardiovascular system and in the coagulability that accompany the pregnant state, which are more significant around delivery and in the postpartum period, likely contribute to increasing the risk of an ischemic stroke. Most of the causes of an ischemic stroke in the young may also occur in pregnant patients. Despite this, there are specific conditions related to pregnancy which may be considered when assessing this particular group of patients such as pre-eclampsia-eclampsia, choriocarcinoma, peripartum cardiomiopathy, amniotic fluid embolization, and postpartum cerebral angiopathy. This article will consider several questions related to pregnancy-associated ischemic stroke, dwelling on epidemiological and specific etiological aspects, diagnostic issue concerning the use of neuroimaging, and the related potential risks to the embryo and fetus. Therapeutic issues surrounding the use of anticoagulant and antiplatelets agents will be discussed along with the few available reports regarding the use of thrombolytic therapy during pregnancy.

  15. Short Telomere Length and Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Madrid, Alexander Scheller; Rode, Line; Nordestgaard, Børge Grønne

    2016-01-01

    are associated with high risk of ischemic heart disease using a Mendelian randomization approach free of reverse causation and of most confounding. METHODS: We genotyped 3 genetic variants in OBFC1 (oligonucleotide/oligosaccharide binding fold containing 1), TERT (telomerase reverse transcriptase), and TERC...

  16. Colonic ischemic necrosis following therapeutic embolization

    International Nuclear Information System (INIS)

    Shenoy, S.S.; Satchidanand, S.; Wesp, E.H.; State Univ. of New York, Buffalo

    1981-01-01

    Transcatheter embolization of the middle colic artery for diverticular bleeding was followed by ischemic necrosis in the transverse colon at the site of previous anastomosis and stricture formation. This is a potential complication of intra-arterial embolization for colonic bleeding. (orig.)

  17. CT diagnosis of hypoxic ischemic encephalopathy

    International Nuclear Information System (INIS)

    Zhao Xiang; Ma Jiwei; Wu Lide

    2004-01-01

    Objective: To explore CT characteristics of hypoxic ischemic encephalopathy (HIE), and to improve the accuracy of CT diagnosis. Methods: 50 cases of neonatal asphyxia in perinatal period diagnosed as hypoxic ischemic encephalopathy by CT was analyzed. Results: The main manifestation of hypoxic ischemic encephalopathy is cerebral edema and intracranial hemorrhage. Focal or diffuse hypo-dense lesion and hyper-dense area in various location and morphology were seen on CT images. (1) Localized diffuse hypo-dense area in 1 or 2 cerebral lobe were found in 17 cases, and the lesions were localized in frontal lobe (n=6), in frontotemporal lobe (n=5), and in temporo-occipital lobe (n=6). (2) Hypo-density region involving more than three cerebral lobes were found in 18 cases, and abnormalities were found in frontotemporal and parietal lobe (n=8), accompanying with subarachnoid hemorrhage (n=2); in frontal, temporal and occipital lobe (n=6), in which cerebral hemorrhage was complicated (n=1); and in other cerebral lobe (n=4). (3) Diffuse low-density region in all cerebral lobe were found in 15 cases, in which subarachnoid hemorrhage was complicated in 4 cases, and ventricular hemorrhage was found in 2 case. Conclusion: CT imaging plays an important role in diagnosis of hypoxic ischemic encephalopathy and has shown its clinical value

  18. Colonic ischemic necrosis following therapeutic embolization

    Energy Technology Data Exchange (ETDEWEB)

    Shenoy, S S; Satchidanand, S; Wesp, E H

    1981-07-15

    Transcatheter embolization of the middle colic artery for diverticular bleeding was followed by ischemic necrosis in the transverse colon at the site of previous anastomosis and stricture formation. This is a potential complication of intra-arterial embolization for colonic bleeding.

  19. Radiopharmaceuticals for diagnosis of ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Komarek, P; Chalabala, M [Institut pro Dalsi Vzdelavani Lekaru a Farmaceutu, Prague (Czechoslovakia)

    1982-01-01

    Radiopharmaceuticals used for diagnosing ischemic heart disease in the experimental and clinical practice are reviewed. The mechanism of their retention by the heart muscle is briefly described. The respective radiopharmaceuticals are divided into preparations imaging disorders in the blood supply of the cardiac muscle, diagnosing the myocardial infarction, and evaluating the contractility of the heart.

  20. ischemic brain injury in neonatal rats

    African Journals Online (AJOL)

    Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, ... Methods: Forty-eight rats (P7-pups) were randomly assigned to one of four groups: ... Keywords: Hypoxic–ischemic brain injury, α-Lipoic acid, Cerebral infarct area, Edema, Antioxidants, .... Of the 48 rats initially used in the current study, 5.

  1. Magnetic resonance imaging in acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Kouichi [Mito Red Cross Hospital (Japan)

    2000-01-01

    This paper summarizes current MRI technology used in the diagnosis of acute cerebral infarction and discusses tasks for further improvement of MRI technology. First, the principles and methods of MRI imaging are described in terms of 1) diffusion-weighted imaging (DWI) and ADC maps, 2) perfusion imaging, 3) the fluid-attenuated inversion recovery (FLAIR) method, and 4) MR angiography (MRA). Then, the actual use of MRI in the early phase of ischemic cerebrovascular disorders is discussed focusing on general MRI procedures, cases in which an ischemic lesion dose not yield a high signal with DWI in the acute phase, and chronological changes in DWI signal strength and ADC. Third, chronological changes in acute cerebrovascular disorder in an animal model of local cerebral ischemia are summarized in terms of expansion of reduced ADC areas and ischemic penumbras in the acute phase of cerebral ischemia. Finally, chronological changes in acute ischemic disorders in patients with cerebrovascular disorders are assessed by reviewing the development of reduced ADC and expansion of DWI lesions. Whether MRI can identify cerebral tissues that can be rescued by the reperfusion method by examining the mismatchs between perfusion images and DWI, relative CBV, and ADC is also discussed. (K.H.)

  2. Cardiac magnetic resonance imaging and computed tomography in ischemic cardiomyopathy: an update

    Directory of Open Access Journals (Sweden)

    Fernanda Boldrini Assunção

    2016-02-01

    Full Text Available Abstract Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI and cardiac computed tomography (CCT are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complementarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies.

  3. Blood microRNAs in Low or No Risk Ischemic Stroke Patients

    Directory of Open Access Journals (Sweden)

    Jun Rong Tan

    2013-01-01

    Full Text Available Ischemic stroke is a multi-factorial disease where some patients present themselves with little or no risk factors. Blood microRNA expression profiles are becoming useful in the diagnosis and prognosis of human diseases. We therefore investigated the blood microRNA profiles in young stroke patients who presented with minimal or absence of risk factors for stroke such as type 2 diabetes, dyslipidemia and hypertension. Blood microRNA profiles from these patients varied with stroke subtypes as well as different functional outcomes (based on modified Rankin Score. These microRNAs have been shown to target genes that are involved in stroke pathogenesis. The findings from our study suggest that molecular mechanisms in stroke pathogenesis involving low or no risk ischemic stroke patients could differ substantially from those with pre-existing risk factors.

  4. Cardiac magnetic resonance imaging and computed tomography in ischemic cardiomyopathy: an update

    Energy Technology Data Exchange (ETDEWEB)

    Assuncao, Fernanda Boldrini; Oliveira, Diogo Costa Leandro de; Nacif, Marcelo Souto, E-mail: msnacif@gmail.com [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Escola de Medicina; Souza, Vitor Frauches [Complexo Hospitalar de Niteroi (CHN), Niteroi, RJ (Brazil)

    2016-01-15

    Ischemic cardiomyopathy is one of the major health problems worldwide, representing a significant part of mortality in the general population nowadays. Cardiac magnetic resonance imaging (CMRI) and cardiac computed tomography (CCT) are noninvasive imaging methods that serve as useful tools in the diagnosis of coronary artery disease and may also help in screening individuals with risk factors for developing this illness. Technological developments of CMRI and CCT have contributed to the rise of several clinical indications of these imaging methods complimentarily to other investigation methods, particularly in cases where they are inconclusive. In terms of accuracy, CMRI and CCT are similar to the other imaging methods, with few absolute contraindications and minimal risks of adverse side-effects. This fact strengthens these methods as powerful and safe tools in the management of patients. The present study is aimed at describing the role played by CMRI and CCT in the diagnosis of ischemic cardiomyopathies. (author)

  5. CT findings in isolated ischemic proctosigmoiditis

    International Nuclear Information System (INIS)

    Wiesner, Walter; Mortele, Koenraad J.; Ji, Hoon; Khurana, Bharti; Ros, Pablo R.; Glickman, Jonathan N.

    2002-01-01

    The purpose of our study was to describe the CT features of ischemic proctosigmoiditis in correlation with clinical, laboratory, endoscopic, and histopathologic findings. Our study included seven patients with isolated ischemic proctosigmoiditis. Patients were identified by a retrospective review of all histopathologic records of colonoscopic biopsies performed during a time period of 4 years. All patients presented with left lower abdominal quadrant pain, bloody stools, and leukocytosis, and four patients had fever at the time of presentation. Four of seven patients suffered from diarrhea, one of seven was constipated and two of seven had normal stool consistency. The CT examinations were reviewed by two authors by consensus and compared with clinical and histopathologic results as well as with the initial CT diagnosis. The CT showed a wall thickening confined to the rectum and sigmoid colon in seven of seven patients, stranding of the pararectal fat in four of seven, and stranding of the perisigmoidal fat in one of seven patients. There were no enlarged lymph nodes, but five of seven patients showed coexistent diverticulosis and in three of these patients CT findings were initially misinterpreted as sigmoid diverticulitis. Endoscopies and histopathologic analyses of endoscopic biopsies confirmed non-transmural ischemic proctosigmoiditis in all patients. Isolated ischemic proctosigmoiditis often presents with unspecific CT features and potentially misleading clinical and laboratory findings. In an elderly patient or a patient with known cardiovascular risk factors the diagnosis of ischemic proctosigmoiditis should be considered when wall thickening confined to the rectum and sigmoid colon is seen that is associated with perirectal fat stranding. (orig.)

  6. Usefulness of colonoscopy in ischemic colitis.

    Science.gov (United States)

    Lozano-Maya, M; Ponferrada-Díaz, A; González-Asanza, C; Nogales-Rincón, O; Senent-Sánchez, C; Pérez-de-Ayala, V; Jiménez-Aleixandre, P; Cos-Arregui, E; Menchén-Fernández-Pacheco, P

    2010-07-01

    the ischemic colitis is intestinal the most frequent cause of ischemia. With this work we determine the demographic and clinical characteristics, and the usefulness of the colonoscopy in the patients with ischemic colitis diagnosed in our centre in relation to a change of therapeutic attitude. retrospective study in which were selected 112 patients diagnosed with ischemic colitis by colonoscopy and biopsy, in a period of five years. It was analyzed: age, sex, reason for examination, factors of cardiovascular risk, endoscopic degree of ischemia, change in the therapeutic attitude, treatment and outcome. the average age was of 73.64 + or - 12.10 years with an equal incidence in women (50.9%) and the men (49.1%). The associated factors were the HTA (61.1%), tobacco (37.2%) and antecedents of cardiovascular episode (52.2%). The most frequent reason for colonoscopy was rectorrhagia (53.6%) followed of the abdominal pain (30.4%), being urgent the 65.3%. Colonoscopy allowed a change in the therapeutic attitude in the 50 increasing in the urgent one to the 65.75%. Global mortality was of 27.67%. The serious ischemic colitis (25%) was more frequent in men (64.3%) in urgent indication (85.71%) and attends with high mortality (53.57%). Surgical treatment in the 57.14% was made with a good evolution in the 50%, whereas the patients with mild or moderate ischemic colitis had a better prognosis (favourable evolution in 80.95%) with smaller requirement of the surgical treatment (4.76%), p change of attitude according to the result of the same one. The evidence of a serious colitis supposed an increase of the necessity of surgery and worse prognosis.

  7. Remote Ischemic Conditioning and Renal Protection.

    Science.gov (United States)

    Giannopoulos, Georgios; Vrachatis, Dimitrios A; Panagopoulou, Vasiliki; Vavuranakis, Manolis; Cleman, Michael W; Deftereos, Spyridon

    2017-07-01

    Over the course of the last 2 decades, the concept of remote ischemic conditioning (RIC) has attracted considerable research interest, because RIC, in most of its embodiments offers an inexpensive way of protecting tissues against ischemic damage inflicted by a number of medical conditions or procedures. Acute kidney injury (AKI) is a common side effect in the context of various medical procedures, and RIC has been suggested as a means of reducing its incidence. Outcomes regarding kidney function have been reported in numerous studies that evaluated the effects of RIC in a variety of settings (eg, cardiac surgery, interventions requiring intravenous administration of contrast media). Although several individual studies have implied a beneficial effect of RIC in preserving kidney function, 3 recently published randomized controlled trials evaluating more than 1000 patients each (Effect of Remote Ischemic Preconditioning in the Cardiac Surgery, Remote Ischaemic Preconditioning for Heart Surgery, and ERICCA) were negative. However, AKI or any other index of renal function was not a stand-alone primary end point in any of these trials. On the other hand, a range of meta-analyses (each including thousands of participants) have reported mixed results, with the most recent among them showing benefit from RIC, pinpointing at the same time a number of shortcomings in published studies, adversely affecting the quality of available data. The present review provides a critical appraisal of the current state of this field of research. It is the opinion of the authors of this review that there is a clear need for a common clinical trial framework for ischemic conditioning studies. If the current babel of definitions, procedures, outcomes, and goals persists, it is most likely that soon ischemic conditioning will be "yesterday's news" with no definitive conclusions having been reached in terms of its real clinical utility.

  8. Navigator-gated 3D blood oxygen level-dependent CMR at 3.0-T for detection of stress-induced myocardial ischemic reactions.

    Science.gov (United States)

    Jahnke, Cosima; Gebker, Rolf; Manka, Robert; Schnackenburg, Bernhard; Fleck, Eckart; Paetsch, Ingo

    2010-04-01

    This study determined the value of navigator-gated 3-dimensional blood oxygen level-dependent (BOLD) cardiac magnetic resonance (CMR) at 3.0-T for the detection of stress-induced myocardial ischemic reactions. Although BOLD CMR has been introduced for characterization of myocardial oxygenation status, previously reported CMR approaches suffered from a low signal-to-noise ratio and motion-related artifacts with impaired image quality and a limited diagnostic value in initial patient studies. Fifty patients with suspected or known coronary artery disease underwent CMR at 3.0-T followed by invasive X-ray angiography within 48 h. Three-dimensional BOLD images were acquired during free breathing with full coverage of the left ventricle in a short-axis orientation. The BOLD imaging was performed at rest and under adenosine stress, followed by stress and rest first-pass perfusion and delayed enhancement imaging. Quantitative coronary X-ray angiography (QCA) was used for coronary stenosis definition (diameter reduction > or =50%). The BOLD and first-pass perfusion images were semiquantitatively evaluated (for BOLD imaging, signal intensity differences between stress and rest [DeltaSI]; for perfusion imaging, myocardial perfusion reserve index [MPRI]). The image quality of BOLD CMR at rest and during adenosine stress was considered good to excellent in 90% and 84% of the patients, respectively. The DeltaSI measurements differed significantly between normal myocardium, myocardium supplied by a stenotic coronary artery, and infarcted myocardium (p exogenous contrast-enhancement studies. Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  9. Legal incentives for minimizing waste

    International Nuclear Information System (INIS)

    Clearwater, S.W.; Scanlon, J.M.

    1991-01-01

    Waste minimization, or pollution prevention, has become an integral component of federal and state environmental regulation. Minimizing waste offers many economic and public relations benefits. In addition, waste minimization efforts can also dramatically reduce potential criminal requirements. This paper addresses the legal incentives for minimizing waste under current and proposed environmental laws and regulations

  10. The ZOOM minimization package

    International Nuclear Information System (INIS)

    Fischler, Mark S.; Sachs, D.

    2004-01-01

    A new object-oriented Minimization package is available for distribution in the same manner as CLHEP. This package, designed for use in HEP applications, has all the capabilities of Minuit, but is a re-write from scratch, adhering to modern C++ design principles. A primary goal of this package is extensibility in several directions, so that its capabilities can be kept fresh with as little maintenance effort as possible. This package is distinguished by the priority that was assigned to C++ design issues, and the focus on producing an extensible system that will resist becoming obsolete

  11. Minimizing the Pacman effect

    International Nuclear Information System (INIS)

    Ritson, D.; Chou, W.

    1997-10-01

    The Pacman bunches will experience two deleterious effects: tune shift and orbit displacement. It is known that the tune shift can be compensated by arranging crossing planes 900 relative to each other at successive interaction points (lPs). This paper gives an analytical estimate of the Pacman orbit displacement for a single as well as for two crossings. For the latter, it can be minimized by using equal phase advances from one IP to another. In the LHC, this displacement is in any event small and can be neglected

  12. Minimally Invasive Parathyroidectomy

    Directory of Open Access Journals (Sweden)

    Lee F. Starker

    2011-01-01

    Full Text Available Minimally invasive parathyroidectomy (MIP is an operative approach for the treatment of primary hyperparathyroidism (pHPT. Currently, routine use of improved preoperative localization studies, cervical block anesthesia in the conscious patient, and intraoperative parathyroid hormone analyses aid in guiding surgical therapy. MIP requires less surgical dissection causing decreased trauma to tissues, can be performed safely in the ambulatory setting, and is at least as effective as standard cervical exploration. This paper reviews advances in preoperative localization, anesthetic techniques, and intraoperative management of patients undergoing MIP for the treatment of pHPT.

  13. Effects of autologous bone marrow stem cell transplantation on beta-adrenoceptor density and electrical activation pattern in a rabbit model of non-ischemic heart failure

    Directory of Open Access Journals (Sweden)

    Ullmann Cris

    2006-06-01

    Full Text Available Abstract Background Since only little is known on stem cell therapy in non-ischemic heart failure we wanted to know whether a long-term improvement of cardiac function in non-ischemic heart failure can be achieved by stem cell transplantation. Methods White male New Zealand rabbits were treated with doxorubicine (3 mg/kg/week; 6 weeks to induce dilative non-ischemic cardiomyopathy. Thereafter, we obtained autologous bone marrow stem cells (BMSC and injected 1.5–2.0 Mio cells in 1 ml medium by infiltrating the myocardium via a left anterolateral thoracotomy in comparison to sham-operated rabbits. 4 weeks later intracardiac contractility was determined in-vivo using a Millar catheter. Thereafter, the heart was excised and processed for radioligand binding assays to detect β1- and β2-adrenoceptor density. In addition, catecholamine plasma levels were determined via HPLC. In a subgroup we investigated cardiac electrophysiology by use of 256 channel mapping. Results In doxorubicine-treated animals β-adrenoceptor density was significantly down-regulated in left ventricle and septum, but not in right ventricle, thereby indicating a typical left ventricular heart failure. Sham-operated rabbits exhibited the same down-regulation. In contrast, BMSC transplantation led to significantly less β-adrenoceptor down-regulation in septum and left ventricle. Cardiac contractility was significantly decreased in heart failure and sham-operated rabbits, but was significantly higher in BMSC-transplanted hearts. Norepinephrine and epinephrine plasma levels were enhanced in heart failure and sham-operated animals, while these were not different from normal in BMSC-transplanted animals. Electrophysiological mapping revealed unaltered electrophysiology and did not show signs of arrhythmogeneity. Conclusion BMSC transplantation improves sympathoadrenal dysregualtion in non-ischemic heart failure.

  14. Study of rNIS as a reporter gene monitoring rBMSC transplanted to rat myocardium

    International Nuclear Information System (INIS)

    Hu Shou; Lan Xiaoli; Cao Wei; Cao Guoxiang; Zhang Guopeng; Zhang Binqing; Wu Tao; Chang Wei; Zhang Yongxue

    2010-01-01

    Objective: To investigate the feasibility of rat sodium/iodide symporter (rNIS) as a reporter gene monitoring rat bone marrow mesenchymal cells (rBMSC) transplanted to rat myocardium in vivo. Methods: Recombinated adenovirus vector was constructed by rNIS/enhanced green fluorescence protein (EGFP) (Ad-rNIS/EGFP). rBMSC transfected by Ad-rNIS/EGFP were studied using fluorescence microscope. Fifteen rats were transplanted with rBMSC and randomly divided into three groups: rNIS group (with rNIS transfection), blocked group (with rNIS transfection) by oral intake of perchloric sodium before planar imaging (GE Millennium MPR SPECT), and control group (without rNIS transfection). All rats underwent 99 Tc m -pertechnetate planar imaging. The biological distribution of 99 Tc m -pertechnetate was studied. The expressions of rNIS gene and protein in myocardium were measured by real time polymerase chain reaction (PCR) and western blot, respectively. The expressions of CD 29 , CD 44 , CD 90 , CD 11 b, CD 34 and CD 45 were measured by immunohistochemistry. Results: rBMSC transfected by Ad-rNIS/EGFP showed EGFP expression under fluorescence microscope. The transplanted rat myocardium could be visualized on 99 Tc m -pertechnetate planar imaging in rNIS group. The relative uptake ratio (R heart /R hmb , RUR) was 6.7 ±0.4. RUR in control group (3.0 ±0.2) was lower than that in rNIS group (t =2.78, P=0.03). The percentage injection dose per gram of tissue (% ID/g) of the transplanted myocardium was 60.2 ± 20.8 in rNIS group, which was higher than that (2.5 ± 0.4) % ID/g of control group ( t = 7.13, P 29 , CD 44 and CD 90 were positive, CD 45 and CD 45 negative CD 11 b mildly positive in the myocardium transplanted with infective rBMSC. Conclusion: rNIS can efficiently monitor rBMSC transplanted to rat myocardium. (authors)

  15. Minimal conformal model

    Energy Technology Data Exchange (ETDEWEB)

    Helmboldt, Alexander; Humbert, Pascal; Lindner, Manfred; Smirnov, Juri [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2016-07-01

    The gauge hierarchy problem is one of the crucial drawbacks of the standard model of particle physics (SM) and thus has triggered model building over the last decades. Its most famous solution is the introduction of low-scale supersymmetry. However, without any significant signs of supersymmetric particles at the LHC to date, it makes sense to devise alternative mechanisms to remedy the hierarchy problem. One such mechanism is based on classically scale-invariant extensions of the SM, in which both the electroweak symmetry and the (anomalous) scale symmetry are broken radiatively via the Coleman-Weinberg mechanism. Apart from giving an introduction to classically scale-invariant models, the talk presents our results on obtaining a theoretically consistent minimal extension of the SM, which reproduces the correct low-scale phenomenology.

  16. Minimal Reducts with Grasp

    Directory of Open Access Journals (Sweden)

    Iris Iddaly Mendez Gurrola

    2011-03-01

    Full Text Available The proper detection of patient level of dementia is important to offer the suitable treatment. The diagnosis is based on certain criteria, reflected in the clinical examinations. From these examinations emerge the limitations and the degree in which each patient is in. In order to reduce the total of limitations to be evaluated, we used the rough set theory, this theory has been applied in areas of the artificial intelligence such as decision analysis, expert systems, knowledge discovery, classification with multiple attributes. In our case this theory is applied to find the minimal limitations set or reduct that generate the same classification that considering all the limitations, to fulfill this purpose we development an algorithm GRASP (Greedy Randomized Adaptive Search Procedure.

  17. Minimally extended SILH

    International Nuclear Information System (INIS)

    Chala, Mikael; Grojean, Christophe; Humboldt-Univ. Berlin; Lima, Leonardo de; Univ. Estadual Paulista, Sao Paulo

    2017-03-01

    Higgs boson compositeness is a phenomenologically viable scenario addressing the hierarchy problem. In minimal models, the Higgs boson is the only degree of freedom of the strong sector below the strong interaction scale. We present here the simplest extension of such a framework with an additional composite spin-zero singlet. To this end, we adopt an effective field theory approach and develop a set of rules to estimate the size of the various operator coefficients, relating them to the parameters of the strong sector and its structural features. As a result, we obtain the patterns of new interactions affecting both the new singlet and the Higgs boson's physics. We identify the characteristics of the singlet field which cause its effects on Higgs physics to dominate over the ones inherited from the composite nature of the Higgs boson. Our effective field theory construction is supported by comparisons with explicit UV models.

  18. Minimally extended SILH

    Energy Technology Data Exchange (ETDEWEB)

    Chala, Mikael [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Valencia Univ. (Spain). Dept. de Fisica Teorica y IFIC; Durieux, Gauthier; Matsedonskyi, Oleksii [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Grojean, Christophe [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Humboldt-Univ. Berlin (Germany). Inst. fuer Physik; Lima, Leonardo de [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Univ. Estadual Paulista, Sao Paulo (Brazil). Inst. de Fisica Teorica

    2017-03-15

    Higgs boson compositeness is a phenomenologically viable scenario addressing the hierarchy problem. In minimal models, the Higgs boson is the only degree of freedom of the strong sector below the strong interaction scale. We present here the simplest extension of such a framework with an additional composite spin-zero singlet. To this end, we adopt an effective field theory approach and develop a set of rules to estimate the size of the various operator coefficients, relating them to the parameters of the strong sector and its structural features. As a result, we obtain the patterns of new interactions affecting both the new singlet and the Higgs boson's physics. We identify the characteristics of the singlet field which cause its effects on Higgs physics to dominate over the ones inherited from the composite nature of the Higgs boson. Our effective field theory construction is supported by comparisons with explicit UV models.

  19. Ischemic stroke: carotid and vertebral artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Vilela, P.; Goulao, A. [Hospital Garcia de Orta, Servico de Neurorradiologia, Almada (Portugal)

    2005-03-01

    Ischemic strokes may have distinct aetiologies, including several different intrinsic arterial pathological disorders. The diagnosis and understanding of these arterial diseases is critical for the correct management of stroke as different treatment approaches are undertaken according to the aetiology. Atherosclerosis is by far the most common arterial disease among adults, and other pathological processes include arterial dissection, small vessel disease, inflammatory and non-inflammatory vasculopathy and vasomotor disorders. In children, there are several vasculopathies responsible for vaso-occlusive disease such as sickle-cell anemia, acute regressive angiopathy and Moya-Moya disease, neurofibromatosis, dissections, vasculitis associated with intracranial and systemic infections. An overview of the major carotid and vertebral pathological diseases responsible for ischemic stroke in adults and children, highlighting the accuracy of the different imaging modalities for its diagnosis and the imaging appearance of these diseases, is given. (orig.)

  20. Ischemic Stroke: Advances in Diagnosis and Management.

    Science.gov (United States)

    Cassella, Courtney R; Jagoda, Andy

    2017-11-01

    Acute ischemic stroke carries the risk of morbidity and mortality. Since the advent of intravenous thrombolysis, there have been improvements in stroke care and functional outcomes. Studies of populations once excluded from thrombolysis have begun to elucidate candidates who might benefit and thus should be engaged in the process of shared decision-making. Imaging is evolving to better target the ischemic penumbra salvageable with prompt reperfusion. Availability and use of computed tomography angiography identifies large-vessel occlusions, and new-generation endovascular therapy devices are improving outcomes in these patients. With this progress in stroke treatment, risk stratification tools and shared decision-making are fundamental. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Sickle cell-induced ischemic colitis.

    Science.gov (United States)

    Stewart, Camille L; Ménard, Geraldine E

    2009-07-01

    Sickle cell-induced ischemic colitis is a rare yet potentially fatal complication of sickle cell anemia. Frequent pain crises with heavy analgesia may obscure and prolong this important diagnosis. Our patient was a 29-year-old female with sickle cell disease who was admitted with left lower quadrant abdominal pain. A diagnostic workup, including chemistries, complete blood count, blood cultures, chest x-ray, computerized tomography scanning, and colonoscopy, was performed to identify the etiology of her symptoms. This case highlights the importance of differentiating simple pain crisis from more serious and life-threatening ischemic bowel. A review of the literature compares this case to others reported and gives a method for diagnosing and treating this complication of sickle cell disease.

  2. Isolated naratriptan-associated ischemic colitis

    Science.gov (United States)

    Nissan, George; Chaudhry, Priyanka; Rangasamy, Priya; Mudrovich, Steven

    2016-01-01

    We report a 41-year-old woman who developed histology- and colonoscopy-proven ischemic colitis with the use of naratriptan not exceeding the maximum 2 doses a day and 3 days per week and without a known medical or cardiovascular history. By exclusion of other causes of colonic ischemia, naratriptan was considered the sole causal agent. Discontinuation of naratriptan resulted in a complete clinical recovery. To date, our patient is the youngest known patient to develop ischemic colitis on isolated naratriptan in the setting of no known medical risk factors or predisposing medical condition. Even though triptans are commonly used for the abortive treatment of migraine headaches, such a reported side effect is rare; however, careful assessment and individual patient-based treatment is advised. PMID:27695179

  3. Ischemic stroke: carotid and vertebral artery disease

    International Nuclear Information System (INIS)

    Vilela, P.; Goulao, A.

    2005-01-01

    Ischemic strokes may have distinct aetiologies, including several different intrinsic arterial pathological disorders. The diagnosis and understanding of these arterial diseases is critical for the correct management of stroke as different treatment approaches are undertaken according to the aetiology. Atherosclerosis is by far the most common arterial disease among adults, and other pathological processes include arterial dissection, small vessel disease, inflammatory and non-inflammatory vasculopathy and vasomotor disorders. In children, there are several vasculopathies responsible for vaso-occlusive disease such as sickle-cell anemia, acute regressive angiopathy and Moya-Moya disease, neurofibromatosis, dissections, vasculitis associated with intracranial and systemic infections. An overview of the major carotid and vertebral pathological diseases responsible for ischemic stroke in adults and children, highlighting the accuracy of the different imaging modalities for its diagnosis and the imaging appearance of these diseases, is given. (orig.)

  4. Ischemic Colitis after Weight-Loss Medication

    Directory of Open Access Journals (Sweden)

    Dan Comay

    2003-01-01

    Full Text Available BACKGROUND: Previous weight-loss medications have received cautious support due to their association with pulmonary hypertension and valvular heart disease. However, newer drugs are increasingly being recommended as potentially safer and more efficacious. We report a case of ischemic colitis possibly linked to the use of a weight-loss drug, and review the literature to highlight an important latent consequence of these medications.

  5. Ischemic Colitis in an Endurance Runner

    Directory of Open Access Journals (Sweden)

    Chase Grames

    2012-01-01

    Full Text Available A 20-year-old female running the Marine Corps Marathon developed diarrhea at mile 12. After finishing the race she noted that she was covered in bloody stool. A local emergency department suspected ischemic colitis. After discharge, her primary care physician instructed her to discontinue the use of all nonsteroidal anti-inflammatory drugs. Her symptoms resolved and she returned to running without any complications. This paper describes the pathophysiology, diagnostic approach, and management options.

  6. Refining the ischemic penumbra with topography.

    Science.gov (United States)

    Thirugnanachandran, Tharani; Ma, Henry; Singhal, Shaloo; Slater, Lee-Anne; Davis, Stephen M; Donnan, Geoffrey A; Phan, Thanh

    2018-04-01

    It has been 40 years since the ischemic penumbra was first conceptualized through work on animal models. The topography of penumbra has been portrayed as an infarcted core surrounded by penumbral tissue and an extreme rim of oligemic tissue. This picture has been used in many review articles and textbooks before the advent of modern imaging. In this paper, we review our understanding of the topography of the ischemic penumbra from the initial experimental animal models to current developments with neuroimaging which have helped to further define the temporal and spatial evolution of the penumbra and refine our knowledge. The concept of the penumbra has been successfully applied in clinical trials of endovascular therapies with a time window as long as 24 h from onset. Further, there are reports of "good" outcome even in patients with a large ischemic core. This latter observation of good outcome despite having a large core requires an understanding of the topography of the penumbra and the function of the infarcted regions. It is proposed that future research in this area takes departure from a time-dependent approach to a more individualized tissue and location-based approach.

  7. Neurovascular regulation in the ischemic brain.

    Science.gov (United States)

    Jackman, Katherine; Iadecola, Costantino

    2015-01-10

    The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory.

  8. ACE Gene in Egyptian Ischemic Stroke Patients.

    Science.gov (United States)

    Mostafa, Magdy A; El-Nabiel, Lobna M; Fahmy, Nagia Aly; Aref, Hany; Shreef, Edrees; Abd El-Tawab, Fathy; Abdulghany, Osama M

    2016-09-01

    Angiotensin-1-converting enzyme (ACE) is a crucial player in vascular homeostasis and in the pathogenesis of atherosclerosis and hypertension. The present study was conducted to determine whether there is an association between the ACE insertion/deletion (I/D) polymorphism and ischemic stroke in Egyptian population. Also, we analyzed the ACE gene I/D polymorphism as a risk factor for small-vessel (SV) versus large-vessel (LV) disease. Sixty patients with ischemic stroke were included: 30 with SV disease and 30 with LV disease. In addition, a control group of 30 apparent healthy subjects were studied. Clinical assessment, computed tomography, magnetic resonance imaging brain, and genetic study using the polymerase chain reaction of ACE gene were done for all subjects. We found that the distribution of ACE gene polymorphism frequency was significantly different between the 3 groups. The DD genotype was far more common in stroke patients compared to controls. It was also significantly more common in each of the patient groups compared to controls but rather similar in the 2 patient groups with SV and LV diseases. We found that the ACE gene deletion/deletion genotype is common in Egyptian patients with non-cardioembolic ischemic stroke but does not appear to be specific neither to SV nor to LV disease. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  9. [Ischemic stroke in the young adult].

    Science.gov (United States)

    Calvet, D

    2016-01-01

    Ischemic stroke is not rare in young adults since one in ten stroke patients are less than 50 years old. This incidence increased over the past last years, mainly due to the rise in the prevalence of traditional vascular risk factors in this sub-group of age but also of illegal drug use. Even though both survival and functional outcome of young stroke patients are better than those observed in older patients, socio-economic and quality of life consequences make this disease a main objective in terms of primary and secondary prevention. Identifying the cause of ischemic stroke in young adults is of major importance to prevent stroke recurrence. However, given the wide variety of potential underlying causes, the etiologic work-up of stroke in young adults requires a different approach from that in the elderly. In this context, a sequential diagnostic work-up is needed in order to optimize the yield of diagnostic tests, to reduce their cost and risks for the patient. Arterial dissection is the most frequent cause of stroke in young adults but other less frequent causes are numerous. Despite a comprehensive work-up, about one third of cases remains unexplained leading to the diagnosis of cryptogenic ischemic stroke. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  10. Hypercholesterolemia in patients of ischemic stroke

    International Nuclear Information System (INIS)

    Saeed, E.; Ali, R.; Din, M.J.U.; Saeed, A.; Jadoon, R.J.

    2015-01-01

    Background: Stroke is a common neurological disease that results in significant mortality and morbidity globally. Several risk factors have been identified for stroke among which hyperlipidaemia is one of the modifiable risk factors. Recent clinical trials have shown a reduction in ischemic stroke for patients taking lipid lowering medications. Therefore, the aim of this study was to find out the frequency of hypercholesterolemia in patients of ischemic stroke in Hazara region. Method: This cross sectional study was carried out in the Medical Department of Ayub Teaching Hospital, Abbottabad. Ninety patients of stroke confirmed as ischemic by CT scan brain were enrolled in the study after informed consent. The frequency of hypercholesterolemia in patients was recorded. Results: There were 55 (61.1 percentage) males. The mean age of patients was 64.4±11.5 years. The mean serum cholesterol in all patients was 4.16±1.1 mmol/l. The mean serum cholesterol of male patients was 4.3±1.2 mmol/l and 4.0±10.9 mmol/l in the case of females. Conclusions: Hypercholesterolemia could not be established as a major risk factor for stroke in our setup through this study that allude to the fact that other risk factors might be contributing more to the incidence of cerebrovascular accident in our population. (author)

  11. Orchiectomy as a result of ischemic orchitis after laparoscopic inguinal hernia repair: case report of a rare complication.

    Science.gov (United States)

    Moore, John B; Hasenboehler, Erik A

    2007-11-07

    Ischemic orchitis is an established complication after open inguinal hernia repair, but ischemic orchitis resulting in orchiectomy after the laparoscopic approach has not been reported. The patient was a thirty-three year-old man who presented with bilateral direct inguinal hernias, right larger than left. He was a thin, muscular male with a narrow pelvis who underwent bilateral extraperitoneal mesh laparoscopic inguinal hernia repair. The case was complicated by pneumoperitoneum which limited the visibility of the pelvic anatomy; however, the mesh was successfully deployed bilaterally. Cautery was used to resect the direct sac on the right. The patient was discharged the same day and doing well with minimal pain and swelling until the fourth day after surgery. That night he presented with sudden-onset pain and swelling of his right testicle and denied both trauma to the area and any sexual activity. Ultrasound of the testicle revealed no blood flow to the testicle which required exploration and subsequent orchiectomy. Ischemic orchitis typically presents 2-3 days after inguinal hernia surgery and can progress to infarction. This ischemic injury is likely due to thrombosis of the venous plexus, rather than iatrogenic arterial injury or inappropriate closure of the inguinal canal. Ultrasound/duplex scanning of the postoperative acute scrotum can help differentiate ischemic orchitis from infarction. Unfortunately, testicular torsion cannot be ruled out and scrotal exploration may be necessary. Although ischemic orchitis, atrophy, and orhiectomy are uncommon complications, all patients should be warned of these potential complications and operative consent should include these risks irrespective of the type of hernia or the surgical approach.

  12. Orchiectomy as a result of ischemic orchitis after laparoscopic inguinal hernia repair: case report of a rare complication

    Directory of Open Access Journals (Sweden)

    Moore John B

    2007-11-01

    Full Text Available Abstract Background Ischemic orchitis is an established complication after open inguinal hernia repair, but ischemic orchitis resulting in orchiectomy after the laparoscopic approach has not been reported. Case presentation The patient was a thirty-three year-old man who presented with bilateral direct inguinal hernias, right larger than left. He was a thin, muscular male with a narrow pelvis who underwent bilateral extraperitoneal mesh laparoscopic inguinal hernia repair. The case was complicated by pneumoperitoneum which limited the visibility of the pelvic anatomy; however, the mesh was successfully deployed bilaterally. Cautery was used to resect the direct sac on the right. The patient was discharged the same day and doing well with minimal pain and swelling until the fourth day after surgery. That night he presented with sudden-onset pain and swelling of his right testicle and denied both trauma to the area and any sexual activity. Ultrasound of the testicle revealed no blood flow to the testicle which required exploration and subsequent orchiectomy. Conclusion Ischemic orchitis typically presents 2–3 days after inguinal hernia surgery and can progress to infarction. This ischemic injury is likely due to thrombosis of the venous plexus, rather than iatrogenic arterial injury or inappropriate closure of the inguinal canal. Ultrasound/duplex scanning of the postoperative acute scrotum can help differentiate ischemic orchitis from infarction. Unfortunately, testicular torsion cannot be ruled out and scrotal exploration may be necessary. Although ischemic orchitis, atrophy, and orhiectomy are uncommon complications, all patients should be warned of these potential complications and operative consent should include these risks irrespective of the type of hernia or the surgical approach.

  13. Characterization of the functional and anatomical differences in the atrial and ventricular myocardium from three species of elasmobranch fishes

    DEFF Research Database (Denmark)

    Larsen, Julie; Bushnell, Peter; Steffensen, John

    2017-01-01

    We assessed the functional properties in atrial and ventricular myocardium (using isolated cardiac strips) of smooth dogfish (Mustelus canis), clearnose skate (Raja eglanteria), and sandbar shark (Carcharhinus plumbeus) by blocking Ca2+ release from the sarcoplasmic reticulum (SR) with ryanodine...... positive first derivative (i.e., contractility), and increased time to 50 % relaxation in atrial tissue from smooth dogfish at 30 °C. It also increased times to peak force and half relaxation in clearnose skate atrial and ventricular tissue at both temperatures, but only in atrial tissue from sandbar shark...... at 30 °C; indicating that SR involvement in excitation–contraction (EC) coupling is species- and temperature-specific in elasmobranch fishes, as it is in teleost fishes. Atrial and ventricular myocardium from all three species displayed a negative force–frequency relationship, but there was no evidence...

  14. The Potential of Tetrandrine as a Protective Agent for Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Sheng-Hong Tseng

    2011-09-01

    Full Text Available Stroke is one of the leading causes of mortality, with a high incidence of severe morbidity in survivors. The treatment to minimize tissue injury after stroke is still unsatisfactory and it is mandatory to develop effective treatment strategies for stroke. The pathophysiology of ischemic stroke is complex and involves many processes including energy failure, loss of ion homeostasis, increased intracellular calcium level, platelet aggregation, production of reactive oxygen species, disruption of blood brain barrier, and inflammation and leukocyte infiltration, etc. Tetrandrine, a bisbenzylisoquinoline alkaloid, has many pharmacologic effects including anti-inflammatory and cytoprotective effects. In addition, tetrandrine has been found to protect the liver, heart, small bowel and brain from ischemia/reperfusion injury. It is a calcium channel blocker, and can inhibit lipid peroxidation, reduce generation of reactive oxygen species, suppress the production of cytokines and inflammatory mediators, inhibit neutrophil recruitment and platelet aggregation, which are all devastating factors during ischemia/reperfusion injury of the brain. Because tetrandrine can counteract these important pathophysiological processes of ischemic stroke, it has the potential to be a protective agent for ischemic stroke.

  15. Regulated production of free radicals by the mitochondrial electron transport chain: Cardiac ischemic preconditioning.

    Science.gov (United States)

    Matsuzaki, Satoshi; Szweda, Pamela A; Szweda, Luke I; Humphries, Kenneth M

    2009-11-30

    Excessive production of free radicals by mitochondria is associated with, and likely contributes to, the progression of numerous pathological conditions. Nevertheless, the production of free radicals by the mitochondria may have important biological functions under normal or stressed conditions by activating or modulating redox-sensitive cellular signaling pathways. This raises the intriguing possibility that regulated mitochondrial free radical production occurs via mechanisms that are distinct from pathologies associated with oxidative damage. Indeed, the capacity of mitochondria to produce free radicals in a limited manner may play a role in ischemic preconditioning, the phenomenon whereby short bouts of ischemia protect from subsequent prolonged ischemia and reperfusion. Ischemic preconditioning can thus serve as an important model system for defining regulatory mechanisms that allow for transient, signal-inducing, production of free radicals by mitochondria. Defining how these mechanism(s) occur will provide insight into therapeutic approaches that minimize oxidative damage without altering normal cellular redox biology. The aim of this review is to present and discuss evidence for the regulated production of superoxide by the electron transport chain within the ischemic preconditioning paradigm of redox regulation.

  16. Klotho upregulation contributes to the neuroprotection of ligustilide against cerebral ischemic injury in mice.

    Science.gov (United States)

    Long, Fang-Yi; Shi, Meng-Qi; Zhou, Hong-Jing; Liu, Dong-Ling; Sang, Na; Du, Jun-Rong

    2018-02-05

    Klotho, an aging-suppressor gene, encodes a protein that potentially acts as a neuroprotective factor. Our previous studies showed that ligustilide minimizes the cognitive dysfunction and brain damage induced by cerebral ischemia; however, the underlying mechanisms remain unclear. This study aims to investigate whether klotho is involved in the protective effects of ligustilide against cerebral ischemic injury in mice. Cerebral ischemia was induced by bilateral common carotid arterial occlusion. Neurobehavioral tests as well as Nissl and Fluoro-Jade B staining were used to evaluate the protective effects of ligustilide in cerebral ischemia, and Western blotting and ELISA approaches were used to investigate the underlying mechanisms. Administration of ligustilide prevented the development of neurological deficits and reduced neuronal loss in the hippocampal CA1 region and the caudate putamen after cerebral ischemia. The protective effects were associated with inhibition of the RIG-I/NF-κB p65 and Akt/FoxO1 pathways and with prevention of inflammation and oxidative stress in the brain. Further, downregulation of klotho could attenuate the neuroprotection of ligustilide against cerebral ischemic injury. Ligustilide exerted neuroprotective effects in mice after cerebral ischemia by regulating anti-inflammatory and anti-oxidant signaling pathways. Furthermore, klotho upregulation contributes to the neuroprotection of LIG against cerebral ischemic injury. These results indicated that ligustilide may be a promising therapeutic agent for the treatment of cerebral ischemia. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Potential roles of cell-derived microparticles in ischemic brain disease.

    Science.gov (United States)

    Horstman, Lawrence L; Jy, Wenche; Bidot, Carlos J; Nordberg, Mary L; Minagar, Alireza; Alexander, J Steven; Kelley, Roger E; Ahn, Yeon S

    2009-10-01

    The objective of this study is to review the role of cell-derived microparticles in ischemic cerebrovascular diseases. An extensive PubMed search of literature pertaining to this study was performed in April 2009 using specific keyword search terms related to cell-derived microparticles and ischemic stroke. Some references are not cited here as it is not possible to be all inclusive or due to space limitation. Cell-derived microparticles are small membranous vesicles released from the plasma membranes of platelets, leukocytes, red cells and endothelial cells in response to diverse biochemical agents or mechanical stresses. They are the main carriers of circulating tissue factor, the principal initiator of intravascular thrombosis, and are implicated in a variety of thrombotic and inflammatory disorders. This review outlines evidence suggesting that cell-derived microparticles are involved predominantly with microvascular, as opposed to macrovascular, thrombosis. More specifically, cell-derived microparticles may substantially contribute to ischemic brain disease in several settings, as well as to neuroinflammatory conditions. If further work confirms this hypothesis, novel therapeutic strategies for minimizing cell-derived microparticles-mediated ischemia are available or can be developed, as discussed.

  18. Minimal Marking: A Success Story

    Science.gov (United States)

    McNeilly, Anne

    2014-01-01

    The minimal-marking project conducted in Ryerson's School of Journalism throughout 2012 and early 2013 resulted in significantly higher grammar scores in two first-year classes of minimally marked university students when compared to two traditionally marked classes. The "minimal-marking" concept (Haswell, 1983), which requires…

  19. Infarct-remodeled myocardium is receptive to protection by isoflurane postconditioning: role of protein kinase B/Akt signaling.

    Science.gov (United States)

    Feng, Jianhua; Fischer, Gregor; Lucchinetti, Eliana; Zhu, Min; Bestmann, Lukas; Jegger, David; Arras, Margarete; Pasch, Thomas; Perriard, Jean-Claude; Schaub, Marcus C; Zaugg, Michael

    2006-05-01

    Postinfarct remodeled myocardium exhibits numerous structural and biochemical alterations. So far, it is unknown whether postconditioning elicited by volatile anesthetics can also provide protection in the remodeled myocardium. Myocardial infarct was induced in male Wistar rats by ligation of the left anterior descending coronary artery. Six weeks later, hearts were buffer-perfused and exposed to 40 min of ischemia followed by 90 min of reperfusion. Anesthetic postconditioning was induced by 15 min of 2.1 vol% isoflurane. In some experiments, LY294002 (15 microM), a phosphatidylinositol 3-kinase inhibitor, was coadministered with isoflurane. Masson's trichrome staining, immunohistochemistry, Western blot analysis, and reverse-transcription polymerase chain reaction served to confirm remodeling. In buffer-perfused hearts, functional recovery was recorded, and acute infarct size was measured using 1% triphenyltetrazolium chloride staining and lactate dehydrogenase release during reperfusion. Western blot analysis was used to determine phosphorylation of reperfusion injury salvage kinases including protein kinase B/Akt and its downstream targets after 15 min of reperfusion. Infarct hearts exhibited typical macroscopic and molecular changes of remodeling. Isoflurane postconditioning improved functional recovery and decreased acute infarct size, as determined by triphenyltetrazolium (35 +/- 5% in unprotected hearts vs. 8 +/- 3% in anesthetic postconditioning; P protection was abolished by LY294002, which inhibited phosphorylation of protein kinase B/Akt and its downstream targets glycogen synthase kinase 3beta, endothelial nitric oxide synthase, and p70S6 kinase. Infarct-remodeled myocardium is receptive to protection by isoflurane postconditioning via protein kinase B/Akt signaling. This is the first time to demonstrate that anesthetic postconditioning retains its marked protection in diseased myocardium.

  20. Swarm robotics and minimalism

    Science.gov (United States)

    Sharkey, Amanda J. C.

    2007-09-01

    Swarm Robotics (SR) is closely related to Swarm Intelligence, and both were initially inspired by studies of social insects. Their guiding principles are based on their biological inspiration and take the form of an emphasis on decentralized local control and communication. Earlier studies went a step further in emphasizing the use of simple reactive robots that only communicate indirectly through the environment. More recently SR studies have moved beyond these constraints to explore the use of non-reactive robots that communicate directly, and that can learn and represent their environment. There is no clear agreement in the literature about how far such extensions of the original principles could go. Should there be any limitations on the individual abilities of the robots used in SR studies? Should knowledge of the capabilities of social insects lead to constraints on the capabilities of individual robots in SR studies? There is a lack of explicit discussion of such questions, and researchers have adopted a variety of constraints for a variety of reasons. A simple taxonomy of swarm robotics is presented here with the aim of addressing and clarifying these questions. The taxonomy distinguishes subareas of SR based on the emphases and justifications for minimalism and individual simplicity.

  1. Minimal dilaton model

    Directory of Open Access Journals (Sweden)

    Oda Kin-ya

    2013-05-01

    Full Text Available Both the ATLAS and CMS experiments at the LHC have reported the observation of the particle of mass around 125 GeV which is consistent to the Standard Model (SM Higgs boson, but with an excess of events beyond the SM expectation in the diphoton decay channel at each of them. There still remains room for a logical possibility that we are not seeing the SM Higgs but something else. Here we introduce the minimal dilaton model in which the LHC signals are explained by an extra singlet scalar of the mass around 125 GeV that slightly mixes with the SM Higgs heavier than 600 GeV. When this scalar has a vacuum expectation value well beyond the electroweak scale, it can be identified as a linearly realized version of a dilaton field. Though the current experimental constraints from the Higgs search disfavors such a region, the singlet scalar model itself still provides a viable alternative to the SM Higgs in interpreting its search results.

  2. Minimal mirror twin Higgs

    Energy Technology Data Exchange (ETDEWEB)

    Barbieri, Riccardo [Institute of Theoretical Studies, ETH Zurich,CH-8092 Zurich (Switzerland); Scuola Normale Superiore,Piazza dei Cavalieri 7, 56126 Pisa (Italy); Hall, Lawrence J.; Harigaya, Keisuke [Department of Physics, University of California,Berkeley, California 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory,Berkeley, California 94720 (United States)

    2016-11-29

    In a Mirror Twin World with a maximally symmetric Higgs sector the little hierarchy of the Standard Model can be significantly mitigated, perhaps displacing the cutoff scale above the LHC reach. We show that consistency with observations requires that the Z{sub 2} parity exchanging the Standard Model with its mirror be broken in the Yukawa couplings. A minimal such effective field theory, with this sole Z{sub 2} breaking, can generate the Z{sub 2} breaking in the Higgs sector necessary for the Twin Higgs mechanism. The theory has constrained and correlated signals in Higgs decays, direct Dark Matter Detection and Dark Radiation, all within reach of foreseen experiments, over a region of parameter space where the fine-tuning for the electroweak scale is 10-50%. For dark matter, both mirror neutrons and a variety of self-interacting mirror atoms are considered. Neutrino mass signals and the effects of a possible additional Z{sub 2} breaking from the vacuum expectation values of B−L breaking fields are also discussed.

  3. New Treatments for Nonarteritic Anterior Ischemic Optic Neuropathy.

    Science.gov (United States)

    Foroozan, Rod

    2017-02-01

    Despite increasing knowledge about the risk factors and clinical findings of nonarteritic anterior ischemic optic neuropathy (NAION), the treatment of this optic neuropathy has remained limited and without clear evidence-based benefit. Historical treatments of NAION are reviewed, beginning with the Ischemic Optic Neuropathy Decompression Trial. More recent treatments are placed within the historical context and illustrate the need for evidence-based therapy for ischemic optic neuropathy. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Improving the Translation of Animal Ischemic Stroke Studies to Humans

    OpenAIRE

    Jickling, Glen C; Sharp, Frank R

    2014-01-01

    Despite testing more than 1026 therapeutic strategies in models ischemic stroke and 114 therapies in human ischemic stroke, only one agent tissue plasminogen activator has successfully been translated to clinical practice as a treatment for acute stroke. Though disappointing, this immense body of work has led to a rethinking of animal stroke models and how to better translate therapies to patients with ischemic stroke. Several recommendations have been made, including the STAIR recommendation...

  5. Neonatal ischemic brain injury: what every radiologist needs to know

    Energy Technology Data Exchange (ETDEWEB)

    Badve, Chaitra A.; Khanna, Paritosh C.; Ishak, Gisele E. [Seattle Children' s Hospital, University of Washington Medical Center, Department of Radiology, Seattle, WA (United States)

    2012-05-15

    We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested. (orig.)

  6. Structural alterations in rat myocardium induced by chronic l-arginine and l-NAME supplementation

    Directory of Open Access Journals (Sweden)

    Amal Abdussalam Ali A. Hmaid

    2018-03-01

    Full Text Available Structural changes affecting cardiomyocyte function may contribute to the pathophysiological remodeling underlying cardiac function impairment. Recent reports have shown that endogenous nitric oxide (NO plays an important role in this process. In order to examine the role of NO in cardiomyocyte remodeling, male rats were acclimated to room temperature (22 ± 1 °C or cold (4 ± 1 °C and treated with 2.25% l-arginine·HCl or 0.01% l-NAME (Nω-nitro-l-arginine methyl ester·HCl for 45 days. Untreated groups served as controls. Right heart ventricles were routinely prepared for light microscopic examination. Stereological estimations of volume densities of cardiomyocytes, surrounding blood vessels and connective tissue, as well as the morphometric measurements of cardiomyocyte diameters were performed. Tissue sections were also analyzed for structural alterations. We observed that both l-arginine and l-NAME supplementation induced cardiomyocyte hypertrophy, regardless of ambient temperature. However, cardiomyocyte hypertrophy was associated with fibrosis and extra collagen deposition only in the l-NAME treated group. Taken together, our results suggest that NO has a modulatory role in right heart ventricle remodeling by coordinating hypertrophy of cardiomyocytes and fibrous tissue preventing cardiac fibrosis. Keywords: Cardiomyocyte, Cardiac hypertrophy, l-Arginine, l-NAME, Myocardium

  7. Ultrastructural alterations of atrial myocardium induced by adriamycin in chronically treated animals.

    Science.gov (United States)

    Lambertenghi-Deliliers, G; Zanon, P L; Pozzoli, E F; Bellini, O; Praga, C

    1978-02-28

    The clinical use of adriamycin (AM) is limited by a possible dose-dependent myocardiopathy. Severe lesions of ventricular myocardium widely described by electron microscopy have been correlated to irreversible congestive heart failure. On the other hand, the atrial contractile elements which differ from the ventricular ones because of the presence of the so-called specific granules have rarely been considered. In the work described in this paper, adriamycin was injected into rabbits and mice according to schedules of chronic toxicity. At the end of the treatment the atrial myocells presented diffuse ultrastructural lesions of mitochondria, sarcoplasmic reticulum and myofibrillar bundles. These alterations might be caused by the ribonucleoprotein synthesis inhibition, by a direct drug toxicity or by an energetic crisis due to early mitochondrial lesions. Besides, adriamycin produces a decrease of the specific atrial granules that play a hypothetic role in the metabolism of myocardial cells. However, lack of information about the contents and the exact function of atrial granules does not allow us to conclude that their decrease in treated animals has a pathogenetic significance in myocardiopathy induced by adriamycin.

  8. Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium.

    Science.gov (United States)

    Matějková, Adéla; Šteiner, Ivo

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation.

  9. Fiber architecture in remodeled myocardium revealed with a quantitative diffusion CMR tractography framework and histological validation.

    Science.gov (United States)

    Mekkaoui, Choukri; Huang, Shuning; Chen, Howard H; Dai, Guangping; Reese, Timothy G; Kostis, William J; Thiagalingam, Aravinda; Maurovich-Horvat, Pal; Ruskin, Jeremy N; Hoffmann, Udo; Jackowski, Marcel P; Sosnovik, David E

    2012-10-12

    The study of myofiber reorganization in the remote zone after myocardial infarction has been performed in 2D. Microstructural reorganization in remodeled hearts, however, can only be fully appreciated by considering myofibers as continuous 3D entities. The aim of this study was therefore to develop a technique for quantitative 3D diffusion CMR tractography of the heart, and to apply this method to quantify fiber architecture in the remote zone of remodeled hearts. Diffusion Tensor CMR of normal human, sheep, and rat hearts, as well as infarcted sheep hearts was performed ex vivo. Fiber tracts were generated with a fourth-order Runge-Kutta integration technique and classified statistically by the median, mean, maximum, or minimum helix angle (HA) along the tract. An index of tract coherence was derived from the relationship between these HA statistics. Histological validation was performed using phase-contrast microscopy. In normal hearts, the subendocardial and subepicardial myofibers had a positive and negative HA, respectively, forming a symmetric distribution around the midmyocardium. However, in the remote zone of the infarcted hearts, a significant positive shift in HA was observed. The ratio between negative and positive HA variance was reduced from 0.96 ± 0.16 in normal hearts to 0.22 ± 0.08 in the remote zone of the remodeled hearts (p layers of the myocardium. Tractography-based quantification, performed here for the first time in remodeled hearts, may provide a framework for assessing regional changes in the left ventricle following infarction.

  10. Automatic segmentation of myocardium from black-blood MR images using entropy and local neighborhood information.

    Directory of Open Access Journals (Sweden)

    Qian Zheng

    Full Text Available By using entropy and local neighborhood information, we present in this study a robust adaptive Gaussian regularizing Chan-Vese (CV model to segment the myocardium from magnetic resonance images with intensity inhomogeneity. By utilizing the circular Hough transformation (CHT our model is able to detect epicardial and endocardial contours of the left ventricle (LV as circles automatically, and the circles are used as the initialization. In the cost functional of our model, the interior and exterior energies are weighted by the entropy to improve the robustness of the evolving curve. Local neighborhood information is used to evolve the level set function to reduce the impact of the heterogeneity inside the regions and to improve the segmentation accuracy. An adaptive window is utilized to reduce the sensitivity to initialization. The Gaussian kernel is used to regularize the level set function, which can not only ensure the smoothness and stability of the level set function, but also eliminate the traditional Euclidean length term and re-initialization. Extensive validation of the proposed method on patient data demonstrates its superior performance over other state-of-the-art methods.

  11. Dynamic CT perfusion imaging of the myocardium: a technical note on improvement of image quality.

    Directory of Open Access Journals (Sweden)

    Daniela Muenzel

    Full Text Available OBJECTIVE: To improve image and diagnostic quality in dynamic CT myocardial perfusion imaging (MPI by using motion compensation and a spatio-temporal filter. METHODS: Dynamic CT MPI was performed using a 256-slice multidetector computed tomography scanner (MDCT. Data from two different patients-with and without myocardial perfusion defects-were evaluated to illustrate potential improvements for MPI (institutional review board approved. Three datasets for each patient were generated: (i original data (ii motion compensated data and (iii motion compensated data with spatio-temporal filtering performed. In addition to the visual assessment of the tomographic slices, noise and contrast-to-noise-ratio (CNR were measured for all data. Perfusion analysis was performed using time-density curves with regions-of-interest (ROI placed in normal and hypoperfused myocardium. Precision in definition of normal and hypoperfused areas was determined in corresponding coloured perfusion maps. RESULTS: The use of motion compensation followed by spatio-temporal filtering resulted in better alignment of the cardiac volumes over time leading to a more consistent perfusion quantification and improved detection of the extend of perfusion defects. Additionally image noise was reduced by 78.5%, with CNR improvements by a factor of 4.7. The average effective radiation dose estimate was 7.1±1.1 mSv. CONCLUSION: The use of motion compensation and spatio-temporal smoothing will result in improved quantification of dynamic CT MPI using a latest generation CT scanner.

  12. Wearable Multi-Channel Microelectrode Membranes for Elucidating Electrophysiological Phenotypes of Injured Myocardium

    Science.gov (United States)

    Cao, Hung; Yu, Fei; Zhao, Yu; Zhang, Xiaoxiao; Tai, Joyce; Lee, Juhyun; Darehzereshki, Ali; Bersohn, Malcolm; Lien, Ching-Ling; Chi, Neil C.; Tai, Yu-Chong; Hsiai, Tzung K.

    2014-01-01

    Understanding the regenerative capacity of small vertebrate models has provided new insights into the plasticity of injured myocardium. Here, we demonstrated the application of flexible microelectrode arrays (MEAs) in elucidating electrophysiological phenotypes of zebrafish and neonatal mouse models of heart regeneration. The 4-electrode MEA membranes were designed to detect electrical signals in the aquatic environment. They were micro-fabricated to adhere to the non-planar body surface of zebrafish and neonatal mice. The acquired signals were processed to display electrocardiogram (ECG) with high signal-to-noise-ratios, and were validated via the use of conventional micro-needle electrodes. The 4-channel MEA provided signal stability and spatial resolution, revealing the site-specific electrical injury currents such as ST-depression in response to ventricular cryo-injury. Thus, our polymer-based and wearable MEA membranes provided electrophysiological insights in long-term conduction phenotypes for small vertebral models of heart injury and regeneration with a translational implication for monitoring cardiac patients. PMID:24945366

  13. Transmural Variation and Anisotropy of Microvascular Flow Conductivity in the Rat Myocardium

    KAUST Repository

    Smith, Amy F.

    2014-05-28

    Transmural variations in the relationship between structural and fluid transport properties of myocardial capillary networks are determined via continuum modeling approaches using recent three-dimensional (3D) data on the microvascular structure. Specifically, the permeability tensor, which quantifies the inverse of the blood flow resistivity of the capillary network, is computed by volume-averaging flow solutions in synthetic networks with geometrical and topological properties derived from an anatomically-detailed microvascular data set extracted from the rat myocardium. Results show that the permeability is approximately ten times higher in the principal direction of capillary alignment (the "longitudinal" direction) than perpendicular to this direction, reflecting the strong anisotropy of the microvascular network. Additionally, a 30% increase in capillary diameter from subepicardium to subendocardium is shown to translate to a 130% transmural rise in permeability in the longitudinal capillary direction. This result supports the hypothesis that perfusion is preferentially facilitated during diastole in the subendocardial microvasculature to compensate for the severely-reduced systolic perfusion in the subendocardium.

  14. The helical ventricular myocardial band: global, three-dimensional, functional architecture of the ventricular myocardium.

    Science.gov (United States)

    Kocica, Mladen J; Corno, Antonio F; Carreras-Costa, Francesc; Ballester-Rodes, Manel; Moghbel, Mark C; Cueva, Clotario N C; Lackovic, Vesna; Kanjuh, Vladimir I; Torrent-Guasp, Francisco

    2006-04-01

    We are currently witnessing the advent of new diagnostic tools and therapies for heart diseases, but, without serious scientific consensus on fundamental questions about normal and diseased heart structure and function. During the last decade, three successive, international, multidisciplinary symposia were organized in order to setup fundamental research principles, which would allow us to make a significant step forward in understanding heart structure and function. Helical ventricular myocardial band of Torrent-Guasp is the revolutionary new concept in understanding global, three-dimensional, functional architecture of the ventricular myocardium. This concept defines the principal, cumulative vectors, integrating the tissue architecture (i.e. form) and net forces developed (i.e. function) within the ventricular mass. Here we expose the compendium of Torrent-Guasp's half-century long functional anatomical investigations in the light of ongoing efforts to define the integrative approach, which would lead to new understanding of the ventricular form and function by linking across multiple scales of biological organization, as defined in ongoing Physiome project. Helical ventricular myocardial band of Torrent-Guasp may also, hopefully, allow overcoming some difficulties encountered in contemporary efforts to create a comprehensive mathematical model of the heart.

  15. Reduction in beta-myosin heavy chains in stunned myocardium as assessed by nondenaturing gel electrophoresis.

    Science.gov (United States)

    Garcia, S C; Pomblum, V J; Gams, E; Rupp, H; Schipke, J D

    2007-09-01

    Myosin plays a key role in the structure and function of cardiac muscle. Three myosin isoenzymes (V(1), V(2), and V(3)) with different ATPase activities have been identified in mammalian ventricles based on their heavy chain constituents. The relative amount of myosin isoenzymes changes under physiological and pathological conditions. Until now, myosin isoenzymes have frequently been determined using either tube gel (nondenaturing) polyacrylamide gel electrophoresis (PAGE), or gradient or uniform sodium dodecyl sulfate (denaturing) PAGE. Both methods have disadvantages, e.g., a long running time. We developed, therefore, a uniform, nondenaturing PAGE with slab minigel format for analyzing the myosin isoenzymes in normoxic and stunned rabbit hearts. In normoxic hearts of adult rabbits, V(3) predominated over V(1) (46 vs 41%). In turn, in the stunned hearts, V(1) predominated over V(3) (70 vs 30%), and the heterodimeric V(2) was not anymore detectable. This alteration appears to result from a selective loss of myosin heavy chain (MHC)-beta. In parallel, the biochemical markers troponin I and creatine kinase were increased in the stunned hearts. We suggest that alterations of myosin isoenzymes in stunned myocardium can be monitored with native PAGE. The present analysis of myosin isoenzyme appears thus as a new tool for evaluating defects in MHC dimer formation in postischemic hearts.

  16. /sup 31/P-NMR studies of respiratory regulation in the intact myocardium

    Energy Technology Data Exchange (ETDEWEB)

    From, A H.L.; Petein, M A; Zimmer, S W; Michurski, S P; Ugurbil, K

    1986-10-06

    The mechanism by which mitochondrial respiration is coupled to ATP consumption in intact tissues is unclear. The authors determined the relationship between high-energy phosphate levels and oxygen consumption rate in rat hearts operating over a range of workloads and perfused with different substrates. With pyruvate + glucose perfusion, ADP levels were in general very low, and varied with MVO/sub 2/ yielding an apparent K/sub m/ of 25 +- 5 ..mu..M, suggesting regulation of oxidative phosphorylation through availability of ADP. In contrast, with glucose perfusion in the presence or absence of insulin, ADP levels, ADP/ATP ratio or the phosphate potential were relatively constant over the workload range examined and generally not correlated with alterations in MVO/sub 2/; it is suggested that under these conditions, carbon substrate delivery to the mitochondria may control mitochondrial respiration. The common feature of both of the suggested regulatory mechanisms is substrate limitation which, however, is exercised at different metabolic points depending on the carbon substrate available to the myocardium. 19 refs.; 2 figs.; 1 table.

  17. Hypercholesterolemic myocardium is vulnerable to ischemia-reperfusion injury and refractory to sevoflurane-induced protection.

    Directory of Open Access Journals (Sweden)

    Yong Xu

    Full Text Available Recent studies have demonstrated that volatile anesthetic postconditioning confers myocardial protection against ischemia-reperfusion (IR injury through activation of the reperfusion injury salvage kinase (RISK pathway. As RISK has been shown to be impaired in hypercholesterolemia. Therefore, we investigate whether anesthetic-induced cardiac protection was maintained in hypercholesterolemic rats. In the present study, normocholesteolemic or hypercholesterolemic rat hearts were subjected to 30 min of ischemia and 2 h of reperfusion. Animals received 2.4% sevoflurane for 5 min or 3 cycles of 10-s ischemia/10-s reperfusion. The hemodynamic parameters, including left ventricular developed pressure, left ventricular end-diastolic pressure and heart rate, were continuously monitored. The infarct size, apoptosis, p-Akt, p-ERK1/2, p-GSK3β were determined. We found that both sevoflurane and ischemic postconditioning significantly improved heart pump function, reduced infarct size and increased the phosphorylation of Akt, ERK1/2 and their downstream target of GSK3β in the healthy rats. In the hypercholesterolemic rats, neither sevoflurane nor ischemic postconditioning improved left ventricular hemodynamics, reduced infarct size and increased the phosphorylated Akt, ERK1/2 and GSK3β. In contrast, GSK inhibitor SB216763 conferred cardioprotection against IR injury in healthy and hypercholesterolemic hearts. In conclusions, hyperchoesterolemia abrogated sevoflurane-induced cardioprotection against IR injury by alteration of upstream signaling of GSK3β and acute GSK inhibition may provide a novel therapeutic strategy to protect hypercholesterolemic hearts against IR injury.

  18. Appearance of high signal intensity and gadolinium-DTPA contrast enhancement in hypertrophied myocardium by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Yamada, Naoaki; Nagata, Seiki

    1989-01-01

    This study was undertaken to examine the potential role of magnetic resonance imaging (MRI) for evaluating myocardial tissue characterization in hypertrophic cardiomyopathy (HCM). ECG-gated MRI images were acquired in 32 HCM patients and 30 patients with hypertensive heart disease (HHD), using a 1.5 T superconducting magnet system. The thickened areas were depicted as high signal intensities in the septum of 12 HCM patients (38%) and the endocardium of 5 HHD patients (17%). Echocardiography revealed that MRI appearance of high signal intensity was associated with more thickened myocardial wall. For evaluable 16 patients receiving i.v. injection of Gd-DTPA in a dose of 0.1 mM/kg, enhancement effects were observed in 10 patients (63%). High signal intensity appearing in the hypertrophied myocardium, as well as contrast enhancement, may not be characteristic of HCM, but reflect the likelihood of myocardial degeneration associated with the hypertrophied myocardium. Although MRI may not be capable of differentiating tissue characterization in HCM from that in HHD, it may provide different information about tissue characterization in the hypertrophied myocardium from that obtained by other techniques. (N.K.)

  19. Exercise Increases Cystathionine-γ-lyase Expression and Decreases the Status of Oxidative Stress in Myocardium of Ovariectomized Rats.

    Science.gov (United States)

    Tang, Zhiping; Wang, Yujun; Zhu, Xiaoyan; Ni, Xin; Lu, Jianqiang

    2016-01-01

    Exercise could be a therapeutic approach for cardiovascular dysfunction induced by estrogen deficiency. Our previous study has shown that estrogen maintains cystathionine-γ-lyase (CSE) expression and inhibits oxidative stress in the myocardium of female rats. In the present study, we investigated whether exercise improves CSE expression and oxidative stress status and ameliorates isoproterenol (ISO)-induced cardiac damage in ovariectomized (OVX) rats. The results showed that treadmill training restored the ovariectomy-induced reduction of CSE and estrogen receptor (ER)α and decrease of total antioxidant capacity (T-AOC) and increase of malondialdehyde (MDA). The level of CSE was positively correlated to T-AOC and ERα while inversely correlated to MDA. OVX rats showed increases in the serum levels of creatine kinase (CK) and lactate dehydrogenase (LDH) and the percentage of TUNEL staining in myocardium upon ISO insult compared to sham rats. Exercise training significantly reduced the serum levels of LDH and CK and the percentage of TUNEL staining in myocardium upon ISO insult in OVX rats. In cultured cardiomyocytes, ISO treatment decreased cell viability and increased LDH release, while overexpression of CSE increased cell viability and decreased LDH release in the cells upon ISO insult. The results suggest that exercise training improves the oxidative stress status and ameliorates the cardiac damage induced by oxidative stress in OVX rats. The improvement of oxidative stress status by exercise might be at least partially due to upregulation of CSE/H2S signaling.

  20. Discovery of Radioiodinated Monomeric Anthraquinones as a Novel Class of Necrosis Avid Agents for Early Imaging of Necrotic Myocardium.

    Science.gov (United States)

    Wang, Qin; Yang, Shengwei; Jiang, Cuihua; Li, Jindian; Wang, Cong; Chen, Linwei; Jin, Qiaomei; Song, Shaoli; Feng, Yuanbo; Ni, Yicheng; Zhang, Jian; Yin, Zhiqi

    2016-02-16

    Assessment of myocardial viability is deemed necessary to aid in clinical decision making whether to recommend revascularization therapy for patients with myocardial infarction (MI). Dianthraquinones such as hypericin (Hyp) selectively accumulate in necrotic myocardium, but were unsuitable for early imaging after administration to assess myocardial viability. Since dianthraquinones can be composed by coupling two molecules of monomeric anthraquinone and the active center can be found by splitting chemical structure, we propose that monomeric anthraquinones may be effective functional groups for necrosis targetability. In this study, eight radioiodinated monomeric anthraquinones were evaluated as novel necrosis avid agents (NAAs) for imaging of necrotic myocardium. All (131)I-anthraquinones showed high affinity to necrotic tissues and (131)I-rhein emerged as the most promising compound. Infarcts were visualized on SPECT/CT images at 6 h after injection of (131)I-rhein, which was earlier than that with (131)I-Hyp. Moreover, (131)I-rhein showed satisfactory heart-to-blood, heart-to-liver and heart-to-lung ratios for obtaining images of good diagnostic quality. (131)I-rhein was a more promising "hot spot imaging" tracer for earlier visualization of necrotic myocardium than (131)I-Hyp, which supported further development of radiopharmaceuticals based on rhein for SPECT/CT ((123)I and (99m)Tc) or PET/CT imaging ((18)F and (124)I) of myocardial necrosis.

  1. Temporal delta wave and ischemic lesions on MRI

    International Nuclear Information System (INIS)

    Inui, Koji; Kawamoto, Hozumi; Kawakita, Masahiko; Wako, Kazuhisa; Nakashima, Hiromichi; Kamihara, Masanori; Nomura, Junichi

    1994-01-01

    The present study was designed to determine the clinical significance of a temporal low-voltage irregular delta wave (TLID) on EEG. Among 808 EEG records examined during one year at our hospital, the TLID was commonly detected in patients with clinically diagnosed ischemic brain diseases such as multiple infarction. Subsequently, a relation of the TLID to ischemic lesions on MRI was examined in 50 elderly depressive patients. It was found that there was a close correlation between the occurrence of the TLID and small ischemic lesions on MRI (p<0.001). These results suggest that the TLID is a valuable indicator of minor ischemic changes of the brain. (author)

  2. Ischemic perinatal brain damage. Neuropathologic and CT correlations

    Energy Technology Data Exchange (ETDEWEB)

    Crisi, G; Mauri, C; Canossi, G; Della Giustina, E

    1986-01-01

    The term ''hypoxic-ischemic encephalopathy'' covers a large part of neonatal neuropathology including the various forms of intracerebral haemorrhage. In the present work the term is confined to ischemic brain edema and actual infarction, be it diffuse or focal. Eighteen newborns with CT evidence of ischemic brain lesions and infarctual necrosis were selected. Emphasis is placed on current data on neuropathology of ischemic brain edema and its CT appearance. Particular entities such as periventricular leukomalacia and multicystic encephalopathy are discussed. Relationship between CT and temporal profile of cerebral damage is emphasized in order to predict the structural sequelae and the longterm prognosis. 31 refs.

  3. The approach of ischemic colitis case followed by the lower gastrointesitnal bleeding

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    YUKSEL ALTINEL

    2017-03-01

    Full Text Available Colonic vascular ischemia is commonly seen in the descending colon and causes malnutrition and is to be commensurate with the duration of clinical myocardial ischemia. History of cerebrovascular disease, hypertension, with coronary hearth disease, 68-year-old female patient was followed for about 2 weeks with the occasional massive gastrointestinal bleeding complaint. After ceasing oral intake, fluid and electrolyte replacement and a broad-spectrum antibiotic therapy was established. Abdomen bowel wall thickening of the colon in continuity in the CT results were observed with the open SMA SMV. Follow-up colonoscopy was performed from the dentate line at 5 cm starting hemorrhagic and ischemic segments was seen as an area of ​​about 40 cm long. After hemodynamic deterioration she was underwent emergency surgery because of abdominal sensitivity increase. Hartman procedure was performed. Postop pneumonia and pulmonary embolism were suspected. Candida was observed in urine infection. The sudden improving of the patient's postoperative bleeding from the rectal stump where the staple line was, has evolved on the 7th day. The sponges with the adrenaline stopped the bleeding and the hemodynamic support was stabilized with it. The minimal fluid in pelvis was also monitored by ultrasound . The colostomy was fine following the blood supply to the bowel. Later oral intake was started, the general condition of the patient was improved. But on the postoperative day 12 she had suddenly respiratory and cardiac arrest . Finally, the histopathological examination revealed that the ischemic necrosis and purulent some areas could be selected as a morphologic ischemic and necrotic (the intraoperative peritoneal reflection of the level of false membrane formation at the perforation focus off ischemic colitis. Approximately 20% of similar cases were followed with the clinical practice under medical treatment and surgical approach. [J Contemp Med 2017; 7(1.000: 74-76

  4. Stroke Laterality Bias in the Management of Acute Ischemic Stroke.

    Science.gov (United States)

    McCluskey, Gavin; Wade, Carrie; McKee, Jacqueline; McCarron, Peter; McVerry, Ferghal; McCarron, Mark O

    2016-11-01

    Little is known of the impact of stroke laterality on the management process and outcome of patients with acute ischemic stroke (AIS). Consecutive patients admitted to a general hospital over 1 year with supratentorial AIS were eligible for inclusion in the study. Baseline characteristics and risk factors, delays in hospital admission, imaging, intrahospital transfer to an acute stoke unit, stroke severity and classification, length of hospital admission, as well as 10-year mortality were measured and compared among right and left hemisphere AIS patients. There were 141 patients (77 men, 64 women; median age 73 [interquartile range 63-79] years), There were 71 patients with left hemisphere AIS and 70 with right hemisphere AIS. Delays to hospital admission from stroke onset to neuroimaging were similar among right and left hemisphere AIS patients. Delay in transfer to an acute stroke unit (ASU) following hospital admission was on average 14 hours more for right hemisphere compared to left hemisphere AIS patients (P = .01). Laterality was not associated with any difference in 10-year survival. Patients with mild and nondominant AIS merit particular attention to minimize their intrahospital transfer time to an ASU. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  5. MCT1 and MCT4 Expression During Myocardial Ischemic-Reperfusion Injury in the Isolated Rat Heart

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    Yi Zhu

    2013-09-01

    Full Text Available Background/Aims: Myocardium ischemia-reperfusion (I/R injury can be caused by imbalances in cellular metabolism. Lactate, transported by monocarboxylate transporters (MCTs, has been implicated as a mechanism in this process. The present study was designed to investigate the expression and functional role of MCTs in rat hearts during ischemia and reperfusion. Methods: Langendorff-perfused rat hearts were subjected to 20 minutes stabilization, 30 minutes of global ischemia and 60 minutes reperfusion. Hearts were collected serially for detecting expression changes in MCT1, MCT4 during myocardial I/R injury and lactate concentration was measured. Post-ischemic left ventricular function and infract size were determined at end-point, followed by the pretreatment of D-lactate, a competitive inhibitor of MCTs. Results: MCT4 was significantly increased following global ischemia and MCT1 expression was increased during the early stages of reperfusion in isolated rat hearts, while the expression of the ancillary protein CD147 was increased during I/R injury. We determined increases in AMPK phosphorylation status, which was significantly elevated following ischemia and early reperfusion. Blocking monocarboxylate transport by competitive inhibition with D-lactate caused decreased left ventricular performance and increased infarct size. Conclusion: Increased MCT4 expression facilitates lactate extrusion during the ischemic period, while increased MCT1 may facilitate lactate transport into and out of cells simultaneously during early reperfusion, with increases in AMPK phosphorylation status during the myocardial I/R period. Lactate transport by MCTs has a profound protective effect during myocardial ischemia reperfusion injury.

  6. Thrombolysis with Intravenous Tissue Plasminogen Activator (rt-PA) Predicts Favorable Discharge Disposition in Patients with Acute Ischemic Stroke

    Science.gov (United States)

    Ifejika-Jones, Nneka L.; Harun, Nusrat; Mohammed-Rajput, Nareesa A.; Noser, Elizabeth A.; Grotta, James C.

    2011-01-01

    Background and Purpose Acute ischemic stroke patients receiving IV tissue plasminogen activator (rt-PA) within 3 hours of symptom onset are 30% more likely to have minimal disability at three months. During hospitalization, short-term disability is subjectively measured by discharge disposition, whether to home, Inpatient Rehabilitation (IR), Skilled Nursing Facility (SNF) or Subacute Care (Sub). There are no studies assessing the role of rt-PA use as a predictor of post-stroke disposition. Methods Retrospective analysis of all ischemic stroke patients admitted to the University of Texas Houston Medical School (UTHMS) Stroke Service between Jan 2004 and Oct 2009. Baseline demographics and National Institute of Health Stroke Scale (NIHSS) score were collected. Cerebrovascular disease risk factors were used for risk stratification. Results Home vs. IR, SNF, Sub Of 2225 acute ischemic stroke patients, 1019 were discharged home, 1206 to another level of care. Patients who received rt-PA therapy were 1.9 times more likely to be discharged home (P = stroke patients, 719 patients were discharged to acute IR, 371 were discharged to SNF, 116 to Sub. There were no differences in disposition between patients who received rt-PA therapy. Conclusions Stroke patients who receive IV rt-PA for acute ischemic stroke are more 1.9 times more likely to be discharged directly home after hospitalization. This study is limited by its retrospective nature and the undetermined role of psychosocial factors related to discharge. PMID:21293014

  7. Tranexamic Acid Does Not Influence Cardioprotection by Ischemic Preconditioning and Remote Ischemic Preconditioning

    NARCIS (Netherlands)

    van Caster, Patrick; Eiling, Sandra; Boekholt, Yvonne; Behmenburg, Friederike; Dorsch, Marianne; Heinen, André; Hollmann, Markus W.; Huhn, Ragnar

    2018-01-01

    Prior studies have suggested that the antifibrinolytic drug aprotinin increases the infarct size after ischemia and reperfusion (I/R) and attenuates the effect of ischemic preconditioning (IPC). Aprotinin was replaced by tranexamic acid (TXA) in clinical practice. Here, we investigated whether TXA

  8. Cancer in young adults with ischemic stroke.

    Science.gov (United States)

    Aarnio, Karoliina; Joensuu, Heikki; Haapaniemi, Elena; Melkas, Susanna; Kaste, Markku; Tatlisumak, Turgut; Putaala, Jukka

    2015-06-01

    Cancer is a risk factor for ischemic stroke. Little is known about cancer among young adults with ischemic stroke. We studied the frequency of cancer and its association with long-term risk of death among young patients with first-ever ischemic stroke. 1002 patients aged 15 to 49 years, registered in the Helsinki Young Stroke Registry, and with a median follow-up of 10.0 years (interquartile range 6.5-13.8) after stroke were included. Historical and follow-up data were derived from the Finnish Care Register and Statistics Finland. Survival between groups was compared with the Kaplan-Meier life-table method, and Cox proportional hazard models were used to identify factors associated with mortality. One or more cancer diagnosis was made in 77 (7.7%) patients, of whom 39 (3.9%) had cancer diagnosed prestroke. During the poststroke follow-up, 41 (53.2%) of the cancer patients died. Median time from prestroke cancer to stroke was 4.9 (1.0-9.5) years and from stroke to poststroke cancer was 6.7 (2.7-10.9) years. Poststroke cancer was associated with age>40 years, heavy drinking, and cigarette smoking. The cumulative mortality was significantly higher among the cancer patients (68.6%, 95% confidence interval 52.0%-85.3%) compared with patients without cancer (19.7%, 95% confidence interval 16.3%-23.2%). Active cancer at index stroke, melanoma, and lung/respiratory tract cancer had the strongest independent association with death during the follow-up when adjusted for known poststroke mortality prognosticators. Cancer, and especially active cancer and no other apparent cause for stroke, is associated with unfavorable survival among young stroke patients. © 2015 American Heart Association, Inc.

  9. Structural genomic variation in ischemic stroke

    Science.gov (United States)

    Matarin, Mar; Simon-Sanchez, Javier; Fung, Hon-Chung; Scholz, Sonja; Gibbs, J. Raphael; Hernandez, Dena G.; Crews, Cynthia; Britton, Angela; Wavrant De Vrieze, Fabienne; Brott, Thomas G.; Brown, Robert D.; Worrall, Bradford B.; Silliman, Scott; Case, L. Douglas; Hardy, John A.; Rich, Stephen S.; Meschia, James F.; Singleton, Andrew B.

    2008-01-01

    Technological advances in molecular genetics allow rapid and sensitive identification of genomic copy number variants (CNVs). This, in turn, has sparked interest in the function such variation may play in disease. While a role for copy number mutations as a cause of Mendelian disorders is well established, it is unclear whether CNVs may affect risk for common complex disorders. We sought to investigate whether CNVs may modulate risk for ischemic stroke (IS) and to provide a catalog of CNVs in patients with this disorder by analyzing copy number metrics produced as a part of our previous genome-wide single-nucleotide polymorphism (SNP)-based association study of ischemic stroke in a North American white population. We examined CNVs in 263 patients with ischemic stroke (IS). Each identified CNV was compared with changes identified in 275 neurologically normal controls. Our analysis identified 247 CNVs, corresponding to 187 insertions (76%; 135 heterozygous; 25 homozygous duplications or triplications; 2 heterosomic) and 60 deletions (24%; 40 heterozygous deletions;3 homozygous deletions; 14 heterosomic deletions). Most alterations (81%) were the same as, or overlapped with, previously reported CNVs. We report here the first genome-wide analysis of CNVs in IS patients. In summary, our study did not detect any common genomic structural variation unequivocally linked to IS, although we cannot exclude that smaller CNVs or CNVs in genomic regions poorly covered by this methodology may confer risk for IS. The application of genome-wide SNP arrays now facilitates the evaluation of structural changes through the entire genome as part of a genome-wide genetic association study. PMID:18288507

  10. Age features of myocardial remodeling in men with ischemic chronic heart failure and renal dysfunction

    Directory of Open Access Journals (Sweden)

    D. A. Lashkul

    2014-04-01

    Full Text Available In recent years, medicine has faced the problem of "dual epidemic" of heart and kidney failure. Regardless of the degree of heart failure, chronic kidney disease increases the risk of death and cardiac decompensation. Left ventricular hypertrophy (LVH is a well known option of cardiac remodeling and it has higher prevalence among people with impaired renal function. Types of myocardial remodeling identify mortality risk of patients with cardiovascular complications. We know that gender and age are important risk factors for cardiovascular disease. However, in most studies structural remodeling of the myocardium was analyzed without sex and age characteristics. The aim of research is to study the age features of the formation of different types of myocardial remodeling in men with ischemic chronic heart failure and renal dysfunction. Materials and methods. To investigate the age characteristics of cardiac remodeling in men with ischemic chronic heart failure and renal dysfunction structural and functional remodeling of left ventricular myocardium was studied in 277 men (mean age 58,1±9,3 years using Doppler echocardiography. Depending on the glomerular filtration rate, patients were divided into 3 groups: 58 with normal GFR (>90 ml/min/1.73m2, 182 with a slight decrease in GFR (60-90 ml/min/1.73m2 and 37 with moderately reduced GFR (<60 ml/min/1.73m2. Echocardiography was performed using the General Electric VIVID 3 system (General Electric Healthcare, USA with the 2.5–3.5 MHz transducer and Doppler technique. Descriptive statistics are presented as mean±standard deviation for continuous variables and as percentages for categorical variables. Depending on the distribution of the analyzed parameters unpaired Student's t-test or U-Mann-Whitney test were used. Comparisons among all groups for baseline clinical variables were performed with the Pearson χ2 or Fisher exact test for categorical variables. Differences were considered reliable for

  11. CT fogging effect with ischemic cerebral infarcts

    International Nuclear Information System (INIS)

    Becker, H.; Desch, H.; Hacker, H.; Pencz, A.; Frankfurt Univ.

    1979-01-01

    Systematic CT studies on ten patients with persistent ischemic cerebral infarct revealed a constant phenomenon, the fogging effect. The hypodense infarct at the beginning will be isodense, or close to isodense, on the plain CT during the second or third week and at a later stage will be hypodense again. The fogging infarcted area shows homogeneous intensive contrast enhancement. Knowledge of the fogging effect is important for correct interpretation of the CT image and the indication for contrast medium CT. CT without contrast medium may lead to misinterpretation during the second and third week after the onset of cerebral infarction. (orig.) [de

  12. CT fogging effect with ischemic cerebral infarcts

    Energy Technology Data Exchange (ETDEWEB)

    Becker, H; Desch, H; Hacker, H; Pencz, A [Frankfurt Univ. (Germany, F.R.). Abt. fuer Neurologie; Frankfurt Univ. (Germany, F.R.). Abt. fuer Neuroradiologie)

    1979-01-01

    Systematic CT studies on ten patients with persistent ischemic cerebral infarct revealed a constant phenomenon, the fogging effect. The hypodense infarct at the beginning will be isodense, or close to isodense, on the plain CT during the second or third week and at a later stage will be hypodense again. The fogging infarcted area shows homogeneous intensive contrast enhancement. Knowledge of the fogging effect is important for correct interpretation of the CT image and the indication for contrast medium CT. CT without contrast medium may lead to misinterpretation during the second and third week after the onset of cerebral infarction.

  13. MR of the normal and ischemic hip

    International Nuclear Information System (INIS)

    Mitchell, D.G.

    1988-01-01

    Magnetic resonance imaging (MRI) appears to be more sensitive than traditional radiographic and radionuclide methods for detecting early avascular necrosis (AVN) of the femoral head. The authors have found that in addition to its proven value for early detection, MRI can help us characterize individual lesions and understand the pathophysiology of AVN. This chapter reviews the clinical and pathological features of AVN of the femoral head, and describes recent contributions of MRI toward understanding the normal and ischemic hip. This review summarizes the 5-year experience of the MR group at the Hospital of the University of Pennsylvania

  14. Malignant Peritoneal Mesothelioma Mimicking Ischemic Colitis

    Directory of Open Access Journals (Sweden)

    Yuusuke Mitsuka

    2010-07-01

    Full Text Available The prognosis of malignant peritoneal mesothelioma is extremely poor with a mean survival time of 12 months. The initial symptoms are poor and atypical. Because of its rare entity and little knowledge of its treatments, there are few reports of long-term survival. We encountered a very unique case with strong impression on radiological findings of malignant peritoneal methothelioma. We had misdiagnosed it because of the findings and because the time course was similar to that of ischemic colitis. The radiological findings on CT and enema disappeared within one week after antibiotic therapy.

  15. Atrial fibrillation is not uncommon among patients with ischemic stroke and transient ischemic stroke in China.

    Science.gov (United States)

    Yang, Xiaomeng; Li, Shuya; Zhao, Xingquan; Liu, Liping; Jiang, Yong; Li, Zixiao; Wang, Yilong; Wang, Yongjun

    2017-12-04

    Atrial fibrillation (AF) is reported to be a less frequent cause of ischemic stroke in China than in Europe and North America, but it is not clear whether this is due to underestimation. Our aim was to define the true frequency of AF-associated stroke, to determine the yield of 6-day Holter ECG to detect AF in Chinese stroke patients, and to elucidate predictors of newly detected AF. Patients with acute ischemic stroke or transient ischemic attack (TIA) were enrolled in a prospective, multicenter cohort study of 6-day Holter monitoring within 7 days after stroke onset at 20 sites in China between 2013 and 2015. Independent predictors of newly-detected AF were determined by multivariate analysis. Among 1511 patients with ischemic stroke and TIA (mean age 63 years, 33.1% women), 305 (20.2%) had either previously known (196, 13.0%) or AF newly-detected by electrocardiography (53, 3.5%) or by 6-day Holter monitoring (56/1262, 4.4%). A history of heart failure (OR = 4.70, 95%CI, 1.64-13.5), advanced age (OR = 1.06, 95%CI, 1.04-1.09), NIHSS at admission (OR = 1.06, 95%CI, 1.02-1.10), blood high density lipoprotein (HDL) (OR = 1.52, 95%CI, 1.09-2.13), together with blood triglycerides (OR = 0.64, 95%CI, 0.45-0.91) were independently associated with newly-detected AF. Contrary to previous reports, AF-associated stroke is frequent (20%) in China if systemically sought. Prolonged noninvasive cardiac rhythm monitoring importantly increases AF detection in patients with recent ischemic stroke and TIA in China. Advanced age, history of heart failure, and higher admission NIHSS and higher level of HDL were independent indicators of newly-detected AF. NCT02156765 (June 5, 2014).

  16. Ischemic stroke and transient ischemic attack in young adults: risk factors, diagnostic yield, neuroimaging, and thrombolysis.

    Science.gov (United States)

    Ji, Ruijun; Schwamm, Lee H; Pervez, Muhammad A; Singhal, Aneesh B

    2013-01-01

    Approximately 10% to 14% of ischemic strokes occur in young adults. To investigate the yield of diagnostic tests, neuroimaging findings, and treatment of ischemic strokes in young adults. We retrospectively reviewed data from our Get with the Guidelines-Stroke database from 2005 through 2010. University hospital tertiary stroke center. A total of 215 consecutive inpatients aged 18 to 45 years with ischemic stroke/transient ischemic attack. The mean (SD) age was 37.5 (7) years; 51% were male. There were high incidence rates of hypertension (20%), diabetes mellitus (11%), dyslipidemia (38%), and smoking (34%). Relevant abnormalities were shown on cerebral angiography in 136 of 203 patients, on cardiac ultrasonography in 100 of 195, on Holter monitoring in 2 of 192; and on hypercoagulable panel in 30 of 189 patients. Multiple infarcts were observed in 31% and were more prevalent in individuals younger than age 35 years. Relevant arterial lesions were frequently detected in the middle cerebral artery (23%), internal carotid artery (13%), and vertebrobasilar arteries (13%). Cardioembolic stroke occurred in 47% (including 17% with isolated patent foramen ovale), and 11% had undetermined stroke etiology. The median National Institutes of Health Stroke Scale score was 3 (interquartile range, 0-9) and 81% had good outcome at hospital discharge. Of the 29 patients receiving thrombolysis (median National Institutes of Health Stroke Scale score, 14; interquartile range, 9-17), 55% had good outcome at hospital discharge and none developed symptomatic brain hemorrhage. This study shows the contemporary profile of ischemic stroke in young adults admitted to a tertiary stroke center. Stroke etiology can be determined in nearly 90% of patients with modern diagnostic tests. The causes are heterogeneous; however, young adults have a high rate of traditional vascular risk factors. Thrombolysis appears safe and short-term outcomes are favorable.

  17. Fiber architecture in remodeled myocardium revealed with a quantitative diffusion CMR tractography framework and histological validation

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    Mekkaoui Choukri

    2012-10-01

    Full Text Available Abstract Background The study of myofiber reorganization in the remote zone after myocardial infarction has been performed in 2D. Microstructural reorganization in remodeled hearts, however, can only be fully appreciated by considering myofibers as continuous 3D entities. The aim of this study was therefore to develop a technique for quantitative 3D diffusion CMR tractography of the heart, and to apply this method to quantify fiber architecture in the remote zone of remodeled hearts. Methods Diffusion Tensor CMR of normal human, sheep, and rat hearts, as well as infarcted sheep hearts was performed ex vivo. Fiber tracts were generated with a fourth-order Runge-Kutta integration technique and classified statistically by the median, mean, maximum, or minimum helix angle (HA along the tract. An index of tract coherence was derived from the relationship between these HA statistics. Histological validation was performed using phase-contrast microscopy. Results In normal hearts, the subendocardial and subepicardial myofibers had a positive and negative HA, respectively, forming a symmetric distribution around the midmyocardium. However, in the remote zone of the infarcted hearts, a significant positive shift in HA was observed. The ratio between negative and positive HA variance was reduced from 0.96 ± 0.16 in normal hearts to 0.22 ± 0.08 in the remote zone of the remodeled hearts (p Conclusions A significant reorganization of the 3D fiber continuum is observed in the remote zone of remodeled hearts. The positive (rightward shift in HA in the remote zone is greatest in the subepicardium, but involves all layers of the myocardium. Tractography-based quantification, performed here for the first time in remodeled hearts, may provide a framework for assessing regional changes in the left ventricle following infarction.

  18. Do indices of coronary conductance after reperfusion reflect the extent of salvaged myocardium?

    Science.gov (United States)

    Shibata, Takahiro; Watanabe, Hisashi; Tsurusaki, Tetsushi; Minai, Kousuke; Ogawa, Takayuki; Iwano, Keiji; Tamura, Tetsutarou; Yoshida, Satoshi; Mutou, Makoto; Imai, Kamon; Horie, Toshinobu; Mochizuki, Seibu

    2004-05-01

    Existing indices of coronary conductance (hyperemic flow-versus-pressure slope index, FPSI, and zero flow pressure, Pzf) have been developed as measures of microcoronary resistance. These indices, however, refer to cases of normal hearts, and there are no reports studying these indices following acute myocardial infarction. In this study, we investigated whether FPSI and Pzf truly measure the extent of myocardial salvage after successful reperfusion therapy. We also developed a new index of zero pressure flow, Fzp. Nineteen patients who underwent successful reperfusion therapy to the proximal portion of the left anterior descending artery (LAD) were studied. After successful reperfusion therapy, a Doppler wire was placed into the LAD. Aortic pressure was recorded in real time. Results from the aortic pressure and flow meter were combined to produce FPSI, Pzf, and Fzp. All cases underwent a resting thallium (Tl) and BMIPP scintigram within five days of successful reperfusion therapy. Infarcted myocardium was estimated using a severity score calculated from the Tl scintigraphy (TlSS), and the BMIPP (BMIPPSS) was estimated using a severity score. Patients with a TlSS/BMIPPSS ratio of less than 0.4 were assigned to the successful salvage group (group S), while the others were assigned to the failed salvage group (group F). FPSI of group F was 1.91 +/- 0.26 m/sec and of group S was 0.92 +/- 0.43 m/sec (P < 0.01). Pzf of group F was 51 +/- 3 mmHg and of group S was 51 +/- 5 mmHg (NS). Fzp of group F was -98 +/- 16 cm/sec and of group S was -46 +/- 4 cm/sec (P < 0.05). FPSI and the new index of Fzp were useful in estimating the extent of myocardial salvage. Our results suggest that the Pzf index could not differentiate between the two groups.

  19. Myocardial kinetics of thallium-201 after stress in normal and perfusion-reduced canine myocardium

    International Nuclear Information System (INIS)

    Okada, R.D.

    1985-01-01

    Despite the emerging use of quantitative computer programs for assessing myocardial thallium uptake and clearance after exercise, little is known about the kinetics of thallium after exercise stress. Accordingly, 11 mongrel dogs with experimental left anterior descending coronary stenoses were given thallium during norepinephrine infusion to simulate exercise. The infusion was discontinued and thallium activity was monitored regionally using miniature radiation detectors for 3 hours. Heart rate, arterial pressure and double product all increased significantly during norepinephrine infusion. The mean fractional myocardial thallium clearance was lower (0.47 +/- 0.03 [+/- standard error of the mean]) for the stenosis zone than for the no-stenosis zone (0.57 +/- 0.03) (p less than 0.0001). The stress blood flow ratio (stenosis/no-stenosis zone = 0.27 +/- 0.06) was significantly lower than the final thallium activity ratio (0.68 +/- 0.07) (p less than 0.001), consistent with thallium redistribution occurring over the 3-hour period. Myocardial thallium activity in the stenosis zone peaked in a mean of 2.2 minutes, then washed out biexponentially with a final decay constant of 0.0035 +/- 0.0005 min-1. Myocardial thallium activity in the no-stenosis zone peaked within 1 minute in all dogs, then washed out biexponentially, with a final decay constant of 0.0043 +/- 0.0003 (p less than 0.001 compared with stenosis zone). In conclusion, fractional clearance of thallium can differentiate myocardium distal to a coronary artery stenosis from that supplied by a normal coronary vessel

  20. Effect of Ischemic Postconditioning and Atorvastatin in the Prevention of Remote Lung Reperfusion Injury

    Directory of Open Access Journals (Sweden)

    Carlos Henrique Marques dos Santos

    Full Text Available Abstract Objective: The aim of the present study was to evaluate the ability of ischemic postconditioning, atorvastatin and both associated to prevent or minimize reperfusion injury in the lung of rats subjected to ischemia and reperfusion by abdominal aortic clamping. Methods: We used 41 Wistar norvegic rats, which were distributed into 5 groups: ischemia and reperfusion (I/R, ischemic postcondictioning (IPC, postconditioning + atorvastatin (IPC+A, atorvastatin (A and SHAM. It was performed a medium laparotomy, dissection and isolation of the infra-renal abdominal aorta; except for the SHAM group, all the others were submitted to the aortic clamping for 70 minutes (ischemia and posterior clamp removal (reperfusion, 70 minutes. In the IPC and IPC+A groups, postconditioning was performed between the ischemia and reperfusion phases by four cycles of reperfusion and ischemia lasting 30 seconds each. In the IPC+A and A groups, preceding the surgical procedure, administration of 3.4 mg/day of atorvastatin was performed for seven days by gavage. After the surgical procedure, the right caudal lobe was removed from the lung for histological study, using tissue injury score ranging from grade 1 (normal tissue to grade 4 (intense lesion. Results: The mean lung injury was 3.6 in the I/R group, 1.6 in the IPC group, 1.2 in the IPC+A group, 1.2 in the A group, and 1 in the SHAM group (P<0.01. Conclusion: Ischemic postconditioning and atorvastatin were able to minimize lung reperfusion injury, alone or in combination.

  1. Separate effects of ischemia, hypoxia, and contractility on thallium-201 kinetics in rabbit myocardium

    International Nuclear Information System (INIS)

    Leppo, J.A.; Macneil, P.B.; Moring, A.F.; Apstein, C.S.

    1986-01-01

    The effects of hypoxia and ischemia, as well as altered contractility, on thallium-201 ( 201 TI) kinetics were evaluated in 42 isolated isovolumetrically contracting rabbit hearts. In Group A, three subgroups (n = 7 each) were studied that had either normal flow and oxygenation, hypoxia and normal flow, or ischemic flow and normal perfusate oxygen content. In Group B, three subgroups (n = 7 each) were studied and all hearts had normal flow but the contractile state was either enhanced with isoproterenol or impaired by hypocalcemia. A hemoglobin-free buffer perfusate was used in all experiments and multiple timed collections of arterial and coronary sinus effluent were used to model myocardial isotope activity during 30 min of constant uptake followed by 30 min of tracer clearance. During ischemia, hypoxia and hypocalcemia peak developed pressure and peak positive and negative dP/dt were all significantly reduced when compared to normal hemodynamic parameters (p less than 0.01). As expected, isoproterenol significantly elevated these parameters (p less than 0.04). Myocardial 201 TI kinetics were adequately described utilizing a bi-exponential model having a fast and slow component. Only ischemic hearts had significantly lower rate constants for 201 TI uptake and clearance than normal hearts (p less than 0.001). The mean (+/- s.d.) myocardial uptake and clearance rates for 201 TI (%/min) varied between 4.86 +/- 0.87 and 7.18 +/- 1.45 for the remaining groups of hearts. Therefore, myocardial 201 TI kinetics appear to be dominated by coronary flow and may not reflect marked alterations in the metabolic and contractile state. These data suggest that normal 201 TI uptake in impaired or hypercontractile cells, receiving normal flow, may not represent normal cellular function

  2. Minimally invasive injectable short nanofibers of poly(glycerol sebacate) for cardiac tissue engineering

    International Nuclear Information System (INIS)

    Ravichandran, Rajeswari; Venugopal, Jayarama Reddy; Sundarrajan, Subramanian; Mukherjee, Shayanti; Sridhar, Radhakrishnan; Ramakrishna, Seeram

    2012-01-01

    Myocardial tissue lacks the ability to appreciably regenerate itself following myocardial infarction (MI) which ultimately results in heart failure. Current therapies can only retard the progression of disease and hence tissue engineering strategies are required to facilitate the engineering of a suitable biomaterial to repair MI. The aim of this study was to investigate the in vitro properties of an injectable biomaterial for the regeneration of infarcted myocardium. Fabrication of core/shell fibers was by co-axial electrospinning, with poly(glycerol sebacate) (PGS) as core material and poly-l-lactic acid (PLLA) as shell material. The PLLA was removed by treatment of the PGS/PLLA core/shell fibers with DCM:hexane (2:1) to obtain PGS short fibers. These PGS short fibers offer the advantage of providing a minimally invasive injectable technique for the regeneration of infarcted myocardium. The scaffolds were characterized by SEM, FTIR and contact angle and cell–scaffold interactions using cardiomyocytes. The results showed that the cardiac marker proteins actinin, troponin, myosin heavy chain and connexin 43 were expressed more on short PGS fibers compared to PLLA nanofibers. We hypothesized that the injection of cells along with short PGS fibers would increase cell transplant retention and survival within the infarct, compared to the standard cell injection system. (paper)

  3. Adherence to treatment of patients with past ischemic stroke.

    Directory of Open Access Journals (Sweden)

    V. Je. Azarenko

    2018-05-01

    Full Text Available The main task of the general practitioner is managing patients with the effects of ischemic stroke. The improvement of patients adherence to treatment in a significant way contributes to successful secondary prevention of ischemic stroke. Adherence to treatment can be determined through various questionnaires, including Morissky-Green. Currently, the adherence to a long-term drug therapy remains insufficient.

  4. Sonographic and Endoscopic Findings in Cocaine-Induced Ischemic Colitis

    DEFF Research Database (Denmark)

    Leth, Thomas; Wilkens, Rune; Bonderup, Ole Kristian

    2015-01-01

    Cocaine-induced ischemic colitis is a recognized entity. The diagnosis is based on clinical and endoscopic findings. However, diagnostic imaging is helpful in the evaluation of abdominal symptoms and prior studies have suggested specific sonographic findings in ischemic colitis. We report...

  5. Diffusion-weighted MRI in acute posterior ischemic optic neuropathy

    International Nuclear Information System (INIS)

    Srinivasan, Sivasubramanian; Moorthy, Srikant; Sreekumar, KP; Kulkarni, Chinmay

    2012-01-01

    Blindness following surgery, especially cardiac surgery, has been reported sporadically, the most common cause being ischemic optic neuropathy. The role of MRI in the diagnosis of this condition is not well established. We present a case of postoperative posterior ischemic optic neuropathy that was diagnosed on diffusion-weighted MRI

  6. Effects of glycyrrhizin pre-treatment on transient ischemic brain ...

    African Journals Online (AJOL)

    Effects of glycyrrhizin pre-treatment on transient ischemic brain injury in mice. ... on transient ischemic brain injury in mice. Chiyeon Lim, Sehyun Lim, Young-Jun Lee, Bokcheul Kong, Byoungho Lee, Chang-Hyun Kim, Buyeo Kim, Suin Cho ... induced brain damage. Keywords: Glycyrrhizin, licorice, stroke, apoptosis ...

  7. Hospital costs of ischemic stroke and TIA in the Netherlands

    NARCIS (Netherlands)

    Buisman, Leander R.; Tan, Siok Swan; Nederkoorn, Paul J.; Koudstaal, Peter J.; Redekop, William K.

    2015-01-01

    Objectives:There have been no ischemic stroke costing studies since major improvements were implemented in stroke care. We therefore determined hospital resource use and costs of ischemic stroke and TIA in the Netherlands for 2012.Methods:We conducted a retrospective cost analysis using individual

  8. Hospital costs of ischemic stroke and TIA in the Netherlands

    NARCIS (Netherlands)

    L.R. Buisman (Leander); S.S. Tan (Siok Swan); P.J. Nederkoorn (Paul); P.J. Koudstaal (Peter Jan); W.K. Redekop (Ken)

    2015-01-01

    markdownabstractObjectives: There have been no ischemic stroke costing studies since major improvements were implemented in stroke care. We therefore determined hospital resource use and costs of ischemic stroke and TIA in the Netherlands for 2012. Methods: We conducted a retrospective cost

  9. Changes of resting cerebral activities in subacute ischemic stroke patients

    Directory of Open Access Journals (Sweden)

    Ping Wu

    2015-01-01

    Full Text Available This study aimed to detect the difference in resting cerebral activities between ischemic stroke patients and healthy participants, define the abnormal site, and provide new evidence for pathological mechanisms, clinical diagnosis, prognosis prediction and efficacy evaluation of ischemic stroke. At present, the majority of functional magnetic resonance imaging studies focus on the motor dysfunction and the acute stage of ischemic stroke. This study recruited 15 right-handed ischemic stroke patients at subacute stage (15 days to 11.5 weeks and 15 age-matched healthy participants. A resting-state functional magnetic resonance imaging scan was performed on each subject to detect cerebral activity. Regional homogeneity analysis was used to investigate the difference in cerebral activities between ischemic stroke patients and healthy participants. The results showed that the ischemic stroke patients had lower regional homogeneity in anterior cingulate and left cerebrum and higher regional homogeneity in cerebellum, left precuneus and left frontal lobe, compared with healthy participants. The experimental findings demonstrate that the areas in which regional homogeneity was different between ischemic stroke patients and healthy participants are in the cerebellum, left precuneus, left triangle inferior frontal gyrus, left inferior temporal gyrus and anterior cingulate. These locations, related to the motor, sensory and emotion areas, are likely potential targets for the neural regeneration of subacute ischemic stroke patients.

  10. Global Analysis of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J

    2010-01-01

    Many properties of minimal surfaces are of a global nature, and this is already true for the results treated in the first two volumes of the treatise. Part I of the present book can be viewed as an extension of these results. For instance, the first two chapters deal with existence, regularity and uniqueness theorems for minimal surfaces with partially free boundaries. Here one of the main features is the possibility of 'edge-crawling' along free parts of the boundary. The third chapter deals with a priori estimates for minimal surfaces in higher dimensions and for minimizers of singular integ

  11. Minimal Surfaces for Hitchin Representations

    DEFF Research Database (Denmark)

    Li, Qiongling; Dai, Song

    2018-01-01

    . In this paper, we investigate the properties of immersed minimal surfaces inside symmetric space associated to a subloci of Hitchin component: $q_n$ and $q_{n-1}$ case. First, we show that the pullback metric of the minimal surface dominates a constant multiple of the hyperbolic metric in the same conformal...... class and has a strong rigidity property. Secondly, we show that the immersed minimal surface is never tangential to any flat inside the symmetric space. As a direct corollary, the pullback metric of the minimal surface is always strictly negatively curved. In the end, we find a fully decoupled system...

  12. Genetics of Atrial Fibrillation and Possible Implications for Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Robin Lemmens

    2011-01-01

    Full Text Available Atrial fibrillation is the most common cardiac arrhythmia mainly caused by valvular, ischemic, hypertensive, and myopathic heart disease. Atrial fibrillation can occur in families suggesting a genetic background especially in younger subjects. Additionally recent studies have identified common genetic variants to be associated with atrial fibrillation in the general population. This cardiac arrhythmia has important public health implications because of its main complications: congestive heart failure and ischemic stroke. Since atrial fibrillation can result in ischemic stroke, one might assume that genetic determinants of this cardiac arrhythmia are also implicated in cerebrovascular disease. Ischemic stroke is a multifactorial, complex disease where multiple environmental and genetic factors interact. Whether genetic variants associated with a risk factor for ischemic stroke also increase the risk of a particular vascular endpoint still needs to be confirmed in many cases. Here we review the current knowledge on the genetic background of atrial fibrillation and the consequences for cerebrovascular disease.

  13. In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts

    Directory of Open Access Journals (Sweden)

    F Di Meglio

    2009-08-01

    Full Text Available The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR. The amount of proteins characteristic for cardiac cells (a-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively inclines toward an increase in both a-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart.

  14. Bone marrow mononuclear cell implantation in myocardial laser channels in the ischemic heart disease surgery. Long-term results

    Science.gov (United States)

    Chernyavskiy, Alexander; Fomichev, Alexey; Minin, Stanislav; Nikitin, Nikita

    2017-10-01

    Background: The problem of incomplete myocardial revascularization for diffuse and distal lesions of the myocardium is still relevant. We assessed the clinical and instrumental long-term results of autologous bone marrow cell (BMC) implantation in laser channels in ischemic heart disease with diffuse and distal coronary disease. 35 coronary heart disease (CHD) patients with diffuse and distal coronary disease during coronary artery bypass grafting (CABG) underwent BMC implantation in laser channels. The control group consisted of 29 patients. All patients in this group underwent only CABG. Clinical and instrumental assessment of the method's effect was carried out at two weeks, six months, and six years after surgery. Indirect revascularization showed more significant decreasing of the functional class (FC) New York Heart Association (NYHA), myocardial perfusion and contractility improvement. Autologous BMC implantation in laser channels is an effective method of CHD surgical treatment if it is impossible to perform direct myocardial revascularization. The indirect revascularization effect is formed in the first six months after surgery and remains at the same level for six years.

  15. Native T1 value in the remote myocardium is independently associated with left ventricular dysfunction in patients with prior myocardial infarction.

    Science.gov (United States)

    Nakamori, Shiro; Alakbarli, Javid; Bellm, Steven; Motiwala, Shweta R; Addae, Gifty; Manning, Warren J; Nezafat, Reza

    2017-10-01

    To compare remote myocardium native T 1 in patients with chronic myocardial infarction (MI) and controls without MI and to elucidate the relationship of infarct size and native T 1 in the remote myocardium for the prediction of left ventricular (LV) systolic dysfunction after MI. A total of 41 chronic MI (18 anterior MI) patients and 15 age-matched volunteers with normal LV systolic function and no history of MI underwent cardiac magnetic resonance imaging (MRI) at 1.5T. Native T 1 map was performed using a slice interleaved T 1 mapping and late gadolinium enhancement (LGE) imaging. Cine MR was acquired to assess LV function and mass. The remote myocardium native T 1 time was significantly elevated in patients with prior MI, compared to controls, for both anterior MI and nonanterior MI (anterior MI: 1099 ± 30, nonanterior MI: 1097 ± 39, controls: 1068 ± 25 msec, P Remote myocardium native T 1 moderately correlated with LV volume, mass index, and ejection fraction (r = 0.38, 0.50, -0.49, respectively, all P remote myocardium was independently associated with reduced LV ejection fraction, after adjusting for age, gender, infarct size, and comorbidity (β = -0.34, P = 0.03). In chronic MI, the severity of LV systolic dysfunction after MI is independently associated with native T 1 in the remote myocardium. Diffuse myocardial fibrosis in the remote myocardium may play an important pathophysiological role of post-MI LV dysfunction. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1073-1081. © 2017 International Society for Magnetic Resonance in Medicine.

  16. Influence of arterial occlusion on outcome after intravenous thrombolysis for acute ischemic stroke.

    Science.gov (United States)

    Medlin, Friedrich; Amiguet, Michael; Vanacker, Peter; Michel, Patrik

    2015-01-01

    We aimed to assess the interaction between intravenous thrombolysis (IVT) and arterial occlusion on acute cervicocerebral computed tomographic angiography on the outcome of patients with acute ischemic stroke. Patients from the Acute Stroke Registry and Analysis of Lausanne (ASTRAL) registry with onset-to-door-time ≤4 hours, acute cervicocerebral computed tomographic angiography, a premorbid modified Rankin Scale ≤2, and a National Institute of Health Stroke Scale (NIHSS) >4 were selected. Patients with significant intracranial arterial obstruction (≥50%-99%) and undergoing acute endovascular treatment were excluded. An interaction analysis of IVT and initial arterial occlusion for favorable 3 months outcome (modified Rankin Scale <3) were performed with adjustment for potential confounders. Among 654 included patients, 382 (58%) showed arterial occlusion, of whom 263 (69%) received IVT. Two hundred seventy-two showed no/minimal obstruction of whom 139 (51%) received IVT. In the adjusted interaction analysis, there was a trend in favor of the arterial occlusion group (odds ratio [OR]=3.97; 95% confidence interval [CI], 0.83-18.97; P=0.08). IVT (versus no IVT) was associated with better outcome in patients with occlusion (adjusted OR for favorable outcome, 3.01; 95% CI, 1.10-8.28) but not in patients with no/minimal obstruction (OR, 0.76; 95% CI, 0.21-2.74). Conversely, patients with occlusion had a similar rate of favorable outcome as no/minimal obstruction when thrombolysed (OR, 0.5; 95% CI, 0.17-1.47) but had a less favorable outcome without thrombolysis (OR, 0.13; 95% CI, 0.04-0.44). In this retrospective analysis of consecutive patients with acute ischemic stroke, there was a trend for more favorable outcomes with IVT in the setting of initial arterial occlusion than in the setting of no/minimal obstruction. Before confirmation in randomized controlled studies, this information should not influence thrombolysis decisions, however. © 2014 American Heart

  17. Ipsilateral hemiparesis in ischemic stroke patients.

    Science.gov (United States)

    Inatomi, Y; Nakajima, M; Yonehara, T; Ando, Y

    2017-07-01

    To investigate clinical characteristics of ipsilateral hemiparesis in ischemic stroke patients. Patients with acute ischemic stroke were prospectively examined. Ipsilateral hemiparesis was defined as hemiparesis ipsilateral to recent stroke lesions. Patients with ipsilateral hemiparesis were examined with functional neuroimaging studies including transcranial magnetic stimulation (TMS) and functional MRI. Of 8360 patients, ipsilateral hemiparesis was detected in 14 patients (0.17%, mean age 71±6 years, eight men). Lesions responsible for the recent strokes were located in the frontal cortex in three patients, corona radiata in seven, internal capsule in one, and pons in three. These lesions were located along the typical route of the corticospinal tract in all but one patient. Thirteen patients also had a past history of stroke contralateral to the recent lesions; 12 of these had motor deficits contralateral to past stroke lesions. During TMS, ipsilateral magnetic evoked potentials were evoked in two of seven patients and contralateral potentials were evoked in all seven. Functional MRI activated cerebral hemispheres ipsilaterally in eight of nine patients and contralaterally in all nine. Most patients with ipsilateral hemiparesis had a past history of stroke contralateral to the recent one, resulting in motor deficits contralateral to the earlier lesions. Moreover, functional neuroimaging findings indicated an active crossed corticospinal tract in all of the examined patients. Both findings suggest the contribution of the uncrossed corticospinal tract contralateral to stroke lesions as a post-stroke compensatory motor system. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Psoriasis and ischemic coronary artery disease.

    Science.gov (United States)

    Mahiques-Santos, L; Soriano-Navarro, C J; Perez-Pastor, G; Tomas-Cabedo, G; Pitarch-Bort, G; Valcuende-Cavero, F

    2015-03-01

    Psoriasis is a chronic inflammatory disease associated with an increased risk of ischemic coronary artery disease (CAD) in some populations. We aimed to determine the association between these 2 diseases in our geographic area. We performed a cross-sectional study of patient records between 2005 and 2012 in the database (Abucacis, Datamart) that contains all medical case histories in the province of Castellón, Spain. Patients diagnosed with psoriasis were compared with a control group of patients diagnosed with melanocytic nevus. The prevalence of CAD and the presence or absence of the main cardiovascular risk factors were analyzed in each group. A total of 9181 patients with psoriasis and 21925 with melanocytic nevus were studied. Univariate logistic regression analysis showed that CAD was significantly associated with psoriasis, age (in years), sex, hypertension, diabetes mellitus, dyslipidemia, and obesity (P<.05). On adjustment for age, sex, and the other cardiovascular risk factors, multivariate regression analysis established that psoriasis was independently associated with CAD (P<.029). Our findings in a large sample of patients in a Mediterranean area support the hypothesis that patients in this population have an increased risk of ischemic CAD. Copyright © 2014 Elsevier España, S.L.U. and AEDV. All rights reserved.

  19. [Ischemic cholangiopathy induced by extended burns].

    Science.gov (United States)

    Cohen, Laurence; Angot, Emilie; Goria, Odile; Koning, Edith; François, Arnaud; Sabourin, Jean-Christophe

    2013-04-01

    Ischemic cholangiopathy is a recently described entity occurring mainly after hepatic grafts. Very few cases after intensive care unit (ICU) for extended burn injury were reported. We report the case of a 73-year-old woman consulting in an hepatology unit, for a jaundice appearing during a hospitalisation in an intensive care unit and increasing from her leaving from ICU, where she was treated for an extended burn injury. She had no pre-existing biological features of biliary disease. Biological tests were normal. Magnetic resonance imaging acquisitions of biliary tracts pointed out severe stenosing lesions of diffuse cholangiopathy concerning intrahepatic biliary tract, mainly peri-hilar. Biopsie from the liver confirmed the diagnosis, showing a biliary cirrhosis with bile infarcts. This case is the fourth case of ischemic cholangiopathy after extended burn injury, concerning a patient without a prior history of hepatic or biliary illness and appearing after hospitalisation in intensive care unit. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Hyperglycemia, Acute Ischemic Stroke and Thrombolytic Therapy

    Science.gov (United States)

    Bruno, Askiel; Fagan, Susan C.; Ergul, Adviye

    2014-01-01

    Ischemic stroke is a leading cause of disability and is considered now the 4th leading cause of death. Many clinical trials have shown that stroke patients with acute elevation in blood glucose at onset of stroke suffer worse functional outcomes, longer in-hospital stay and higher mortality rates. The only therapeutic hope for these patients is the rapid restoration of blood flow to the ischemic tissue through intravenous administration of the only currently proven effective therapy, tissue plasminogen activator (tPA). However, even this option is associated with the increased risk of intracerebral hemorrhage. Nonetheless, the underlying mechanisms through which hyperglycemia (HG) and tPA worsen the neurovascular injury after stroke are not fully understood. Accordingly, this review summarizes the latest updates and recommendations about the management of HG and co-administration of tPA in a clinical setting while focusing more on the various experimental models studying: 1. the effect of HG on stroke outcomes; 2. the potential mechanisms involved in worsening the neurovasular injury; 3. the different therapeutic strategies employed to ameliorate the injury, and finally; 4. the interaction between HG and tPA. Developing therapeutic strategies to reduce the hemorrhage risk with tPA in hyperglycemic setting is of great clinical importance. This can best be achieved by conducting robust preclinical studies evaluating the interaction between tPA and other therapeutics in order to develop potential therapeutic strategies with high translational impact. PMID:24619488

  1. Proton NMR imaging in experimental ischemic infarction

    International Nuclear Information System (INIS)

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

    1983-01-01

    Proton nuclear magnetic resonance (NMR) images depict the distribution and concentration of mobile protons modified by the relaxation times T1 and T2. Using the steady-state-free-precession (SSFP) technique, serial coronal images were obtained sequentially over time in laboratory animals with experimental ischemic infarction. Image changes were evident as early as 2 hours after carotid artery ligation, and corresponded to areas of ischemic infarction noted pathologically. Resulting SSFP images in experimental stroke are contrasted to inversion-recovery NMR images in an illustrative patient with established cerebral infarction. Bulk T1 and T2 measurements were made in vitro in three groups of gerbils: normal, those with clinical evidence of infarction, and those clinically normal after carotid ligature. Infarcted hemispheres had significantly prolonged T1 and T2 (1.47 +/- .12 sec, 76.0 +/- 9.0 msec, respectively) when compared to the contralateral hemisphere (T1 . 1.28 +/- .05 sec, T2 . 58.7 +/- 3.9 msec) or to the other two groups. These data suggest that changes in NMR parameters occur and can be detected by NMR imaging as early as two hours after carotid artery ligation

  2. Synthetic cannabis and acute ischemic stroke.

    Science.gov (United States)

    Bernson-Leung, Miya E; Leung, Lester Y; Kumar, Sandeep

    2014-01-01

    An association between marijuana use and stroke has been previously reported. However, the health risks of newer synthetic cannabinoid compounds are less well known. We describe 2 cases that introduce a previously unreported association between synthetic cannabis use and ischemic stroke in young adults. A 22-year-old woman presented with dysarthria, left hemiplegia, and left hemianesthesia within hours of first use of synthetic cannabis. She was healthy and without identified stroke risk factors other than oral contraceptive use and a patent foramen ovale without venous thromboses. A 26-year-old woman presented with nonfluent aphasia, left facial droop, and left hemianesthesia approximately 12 hours after first use of synthetic cannabis. Her other stroke risk factors included migraine with aura, oral contraceptive use, smoking, and a family history of superficial thrombophlebitis. Both women were found to have acute, large-territory infarctions of the right middle cerebral artery. Our 2 cases had risk factors for ischemic stroke but were otherwise young and healthy and the onset of their deficits occurred within hours after first-time exposure to synthetic cannabis. Synthetic cannabis use is an important consideration in the investigation of stroke in young adults. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  3. Biomarkers of Hypoxic Ischemic Encephalopathy in Newborns

    Directory of Open Access Journals (Sweden)

    Martha V. Douglas-Escobar

    2012-11-01

    Full Text Available As neonatal intensive care has evolved, the focus has shifted from improving mortality alone to an effort to improve both mortality and morbidity. The most frequent source of neonatal brain injury occurs as a result of hypoxic-ischemic injury. Hypoxic-ischemic injury occurs in about 2 of 1,000 full-term infants and severe injured infants will have lifetime disabilities and neurodevelopmental delays. Most recently, remarkable efforts toward neuroprotection have been started with the advent of therapeutic hypothermia and a key step in the evolution of neonatal neuroprotection is the discovery of biomarkers that enable the clinician-scientist to screen infants for brain injury, monitor progression of disease, identify injured brain regions, and assess efficacy of neuroprotective clinical trials. Lastly, biomarkers offer great hope identifying when an injury occurred shedding light on the potential pathophysiology and the most effective therapy. In this article, we will review biomarkers of HIE including S100b, neuron specific enolase, umbilical cord IL-6, CK-BB, GFAP, myelin basic protein, UCHL-1, and pNF-H. We hope to contribute to the awareness, validation and clinical use of established as well as novel neonatal brain injury biomarkers.

  4. Metabolic Prosthesis for Oxygenation of Ischemic Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias [ORNL

    2009-01-01

    This communication discloses new ideas and preliminary results on the development of a "metabolic prosthesis" for local oxygenation of ischemic tissue under physiological neutral conditions. We report for the first time the selective electrolysis of physiological saline by repetitively pulsed charge-limited electrolysis for the production of oxygen and suppression of free chlorine. For example, using 800 A amplitude current pulses and <200 sec pulse durations, we demonstrated prompt oxygen production and delayed chlorine production at the surface of a shiny 0.85 mm diameter spherical platinum electrode. The data, interpreted in terms of the ionic structure of the electric double layer, suggest a strategy for in situ production of metabolic oxygen via a new class of "smart" prosthetic implants for dealing with ischemic disease such as diabetic retinopathy. We also present data indicating that drift of the local pH of the oxygenated environment can be held constant using a feedback-controlled three electrode electrolysis system that chooses anode and cathode pair based on pH data provided by local microsensors. The work is discussed in the context of diabetic retinopathy since surgical techniques for multielectrode prosthetic implants aimed at retinal degenerative diseases have been developed.

  5. Noninvasive evaluation of ischemic stroke with SPECT

    International Nuclear Information System (INIS)

    Gomez, C.R.; Malik, M.M.; Gomez, S.M.; Wingkun, E.C.

    1988-01-01

    Technetium Tc 99m DTPA single photon emission computerized tomography (SPECT) brain scans of 20 patients with acute ischemic stroke were reviewed retrospectively and compared with clinical and radiologic (CT) data. Fourteen of the patients had abnormal SPECT studies. The abnormal findings were demonstrated by static views in eight patients, by the flow study in one patient, and by both sets of images in the other five patients. All abnormalities correlated with the clinical syndrome of presentation, and only two of the patients had no corresponding lesions on CT. Of the six patients with normal SPECT scans, two had abnormal CT studies, and in the other four, no lesions were shown at all. The ability of /sup 99m/Tc DTPA SPECT to display cerebral infarctions appears to be, at best, comparable to that of CT. SPECT also provides qualitative information regarding flow dynamics in the affected hemisphere of some patients (6/20 in our review). This, we believe, represents the objective demonstration of the preexisting insufficient collateral flow in the hemisphere at risk for ischemic stroke

  6. Thrombophilia testing in young patients with ischemic stroke.

    Science.gov (United States)

    Pahus, Sidse Høst; Hansen, Anette Tarp; Hvas, Anne-Mette

    2016-01-01

    The possible significance of thrombophilia in ischemic stroke remains controversial. We aimed to study inherited and acquired thrombophilias as risk factors for ischemic stroke, transient ischemic attack (TIA) and amaurosis fugax in young patients. We included patients aged 18 to 50 years with ischemic stroke, TIA or amaurosis fugax referred to thrombophilia investigation at Aarhus University Hospital, Denmark from 1 January 2004 to 31 December 2012 (N=685). Clinical information was obtained from the Danish Stroke Registry and medical records. Thrombophilia investigation results were obtained from the laboratory information system. Absolute thrombophilia prevalences and associated odds ratios (OR) with 95% confidence intervals (95% CI) were reported for ischemic stroke (N=377) and TIA or amaurosis fugax (N=308). Thrombophilia prevalences for the general population were obtained from published data. No strong associations were found between thrombophilia and ischemic stroke, but patients with persistent presence of lupus anticoagulant (3%) had an OR at 2.66 (95% CI 0.84-9.15) for ischemic stroke. A significantly higher risk of TIA/amaurosis fugax was found for factor V Leiden heterozygote (12%) (OR: 1.99 (95% CI 1.14-3.28)). No other inherited or acquired thrombophilia was associated with ischemic stroke, TIA or amaurosis fugax. In young patients, thrombophilia did not infer an increased risk of ischemic stroke. Only factor V Leiden heterozygote patients had an increased risk of TIA/amaurosis fugax, and persistent presence of lupus anticoagulant was likely associated with ischemic stroke. We suggest the testing restricted to investigation of persistent presence of lupus anticoagulant. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Prevalence of electrocardiographic ST-T changes during acute ischemic stroke in patients without known ischemic heart disease

    DEFF Research Database (Denmark)

    Jensen, Jesper K; Bak, Søren; Flemming Høilund-Carlsen, Poul

    2008-01-01

    We evaluated characteristics and prevalence of ST-segment depression and/or T-wave inversion in the resting electrocardiogram of 244 consecutive patients with acute ischemic stroke, but without ischemic heart disease. The prevalence of ST-T changes ranged from 13% to 16% and this is what to expect...

  8. Comparison of characteristics and healing course of diabetic foot ulcers by etiological classification: neuropathic, ischemic, and neuro-ischemic type.

    Science.gov (United States)

    Yotsu, Rie Roselyne; Pham, Ngoc Minh; Oe, Makoto; Nagase, Takeshi; Sanada, Hiromi; Hara, Hisao; Fukuda, Shoji; Fujitani, Junko; Yamamoto-Honda, Ritsuko; Kajio, Hiroshi; Noda, Mitsuhiko; Tamaki, Takeshi

    2014-01-01

    To identify differences in the characteristics of patients with diabetic foot ulcers (DFUs) according to their etiological classification and to compare their healing time. Over a 4.5-year period, 73 patients with DFUs were recruited. DFUs were etiologically classified as being of neuropathic, ischemic, or neuro-ischemic origin. Descriptive analyses were performed to characterize study subjects, foot-related factors, and healing outcome and time. Duration of healing was assessed using the Kaplan-Meier method. Healing time among the three types was compared using the log rank test. The number of patients manifesting neuropathic, ischemic, and neuro-ischemic ulcers was 30, 20, and 14, respectively. Differences were identified for age, diabetes duration, body mass index, hypertension, and estimated glomerular filtration rate. Patients with neuro-ischemic ulcers had better ankle-brachial index, skin perfusion pressure (SPP), and transcutaneous oxygen pressure values compared to those with ischemic ulcers. The average time in which 50% of patients had healed wounds was 70, 113, and 233 days for neuropathic, neuro-ischemic, and ischemic ulcers, respectively. Main factors associated with healing were age and SPP values. Based on the etiological ulcer type, DFU healing course and several patient factors differed. Failure to consider the differences in DFU etiology may have led to heterogeneity of results in previous studies on DFUs. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Guidelines for mixed waste minimization

    International Nuclear Information System (INIS)

    Owens, C.

    1992-02-01

    Currently, there is no commercial mixed waste disposal available in the United States. Storage and treatment for commercial mixed waste is limited. Host States and compacts region officials are encouraging their mixed waste generators to minimize their mixed wastes because of management limitations. This document provides a guide to mixed waste minimization

  10. Minimal changes in health status questionnaires: distinction between minimally detectable change and minimally important change

    Directory of Open Access Journals (Sweden)

    Knol Dirk L

    2006-08-01

    Full Text Available Abstract Changes in scores on health status questionnaires are difficult to interpret. Several methods to determine minimally important changes (MICs have been proposed which can broadly be divided in distribution-based and anchor-based methods. Comparisons of these methods have led to insight into essential differences between these approaches. Some authors have tried to come to a uniform measure for the MIC, such as 0.5 standard deviation and the value of one standard error of measurement (SEM. Others have emphasized the diversity of MIC values, depending on the type of anchor, the definition of minimal importance on the anchor, and characteristics of the disease under study. A closer look makes clear that some distribution-based methods have been merely focused on minimally detectable changes. For assessing minimally important changes, anchor-based methods are preferred, as they include a definition of what is minimally important. Acknowledging the distinction between minimally detectable and minimally important changes is useful, not only to avoid confusion among MIC methods, but also to gain information on two important benchmarks on the scale of a health status measurement instrument. Appreciating the distinction, it becomes possible to judge whether the minimally detectable change of a measurement instrument is sufficiently small to detect minimally important changes.

  11. Waste minimization handbook, Volume 1

    International Nuclear Information System (INIS)

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility's life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996

  12. Waste minimization handbook, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility`s life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996.

  13. Minimal Webs in Riemannian Manifolds

    DEFF Research Database (Denmark)

    Markvorsen, Steen

    2008-01-01

    For a given combinatorial graph $G$ a {\\it geometrization} $(G, g)$ of the graph is obtained by considering each edge of the graph as a $1-$dimensional manifold with an associated metric $g$. In this paper we are concerned with {\\it minimal isometric immersions} of geometrized graphs $(G, g......)$ into Riemannian manifolds $(N^{n}, h)$. Such immersions we call {\\em{minimal webs}}. They admit a natural 'geometric' extension of the intrinsic combinatorial discrete Laplacian. The geometric Laplacian on minimal webs enjoys standard properties such as the maximum principle and the divergence theorems, which...... are of instrumental importance for the applications. We apply these properties to show that minimal webs in ambient Riemannian spaces share several analytic and geometric properties with their smooth (minimal submanifold) counterparts in such spaces. In particular we use appropriate versions of the divergence...

  14. Early assessment of tissue viability with radioiodinated heptadecanoic acid in reperfused canine myocardium: Comparison with thallium-201

    International Nuclear Information System (INIS)

    Chappuis, F.; Meier, B.; Belenger, J.; Blaeuenstein, P.L.; Lerch, R.

    1990-01-01

    Myocardial scintigraphy with heptadecanoic acid labeled with iodine-123 (123I-HDA) may allow early noninvasive delineation of viable myocardium after reperfusion. In this study myocardial uptake of 123I-HDA was compared with that of thallium-201 in six closed-chest dogs after 5 hours of occlusion followed by 1 hour of reperfusion of the left anterior descending coronary artery. Myocardial blood flow was measured with microspheres, and myocardial viability was assessed by means of triphenyltetrazolium chloride staining. In viable areas of the reperfused region, 123I-HDA uptake, thallium-201 uptake, and myocardial blood flow were similar to those measured in the control circumflex region. However, in infarcted areas they were reduced to 48 +/- 2% (mean +/- SEM; p less than 0.001), 59 +/- 3% (p less than 0.001), and 74 +/- 5% (p less than 0.001) of control values, respectively. Results of multiple regression analysis showed that thallium-201 uptake primarily reflected the level of flow during reperfusion, whereas 123I-HDA uptake was dependent on both myocardial blood flow and viability. At each level of flow, 123I-HDA uptake was significantly lower in infarcted than in viable myocardium. By means of discriminant analysis, 123I-HDA uptake was found to be the single most important predictor of viability, whereas thallium-201 was only of limited importance. Myocardial 123I-HDA uptake greater than or equal to 71% or myocardial thallium-201 uptake greater than or equal to 73% best differentiated viable from infarcted myocardium. According to these criteria, 123I-HDA predicted myocardial viability with a sensitivity of 77%, a specificity of 84% and a predictive accuracy of 81%

  15. Distribution of beta-adrenergic receptors in failing human myocardium. Implications for mechanisms of down-regulation

    International Nuclear Information System (INIS)

    Murphree, S.S.; Saffitz, J.E.

    1989-01-01

    The density of beta-adrenergic receptors is reduced in crude membranes prepared from failing human myocardium. We used quantitative autoradiography of radioligand binding sites in intact tissue slices to determine whether the total tissue content of receptors is reduced and to characterize the transmural distribution of receptors in cardiac myocytes and the coronary vasculature in hearts obtained from nine cardiac transplant patients with severe congestive failure. Binding of [125Iodo]cyanopindolol to transmural slices of human myocardium was rapid, saturable, stereoselective, and displaceable by agonists and antagonists with an appropriate rank order of potency. Binding isotherms in four normal and nine failing ventricles showed a significant reduction in the total tissue content of beta-receptors in failing myocardium (38.3 +/- 2.0 fmol/mg protein) compared with normal tissue (52.4 +/- 1.7 fmol/mg protein, p = 0.038). In the normal ventricles, the greatest receptor density was observed autoradiographically in myocytic regions of the subendocardium. Receptor density of the coronary arterioles was approximately 70% of that in adjacent myocytic regions. The density of binding sites in both myocytic regions and arterioles was diminished in all regions of the failing ventricles, but down-regulation was due primarily to a selective reduction of beta-receptors of subendocardial myocytes (63 +/- 5% of subepicardial receptor density vs. 115 +/- 6% in controls, p less than 0.0001). These observations indicate that down-regulation occurs nonuniformly in the transmural distribution and thus is likely not related simply to elevated circulating catecholamine levels

  16. 99mTcO(BAT-NI), a novel nitroimidazole tracer: in vivo uptake studies in ischaemic myocardium

    International Nuclear Information System (INIS)

    Hoffend, J.; Linke, G.; Mohammed, A.; Haberkorn, U.; Tiefenbacher, C.P.; Eisenhut, M.

    2003-01-01

    Myocardial perfusion single-photon emission tomography (SPET) performed with cationic technetium-99m complexes indicates ischaemic areas as cold lesions. By contrast, nitroimidazole derivatives labelled with fluorine-18 or 99m Tc have recently shown promising results for hot spot imaging of ischaemic myocardium. This study evaluates 99m TcO(BAT-NI), a new 99m Tc complex comprising the nitroimidazole ligand, 2,10-dimercapto-2, 10-dimethyl-4, 8-diaza-6-[4-(2-nitroimidazolyl)butyl]undecane, in a low-flow in vivo model of myocardial ischaemia in thoracotomised rats. To elucidate the influence of the 2-nitroimidazole group on ischaemia-induced uptake, comparisons with ligand derivatives were performed where (a) the 2-nitro group was deleted [ 99m TcO(BAT-I)], (b) the 2-nitroimidazole functionality was replaced by a Br atom [ 99m TcO(BAT-Br)] and (c) the 99m TcO(BAT) moiety was replaced by an iodine-125 iodophenoxybutyl ligand ( 125 IP-NI). The radiolabelled compounds were i.v. injected 15 min after reducing resting myocardial blood flow by 50-60% and the uptake of radioactivity was assessed 90 min post injection. Autoradiography of left ventricular short-axis slices showed median uptake ratios of ischaemic/non-ischaemic myocardium (I/N) of 3.4, 4.5 and 3.4 for 99m TcO(BAT-NI), 99m TcO(BAT-I) and 99m TcO(BAT-Br), respectively. In contrast, 125 IP-NI was not preferentially taken up by ischaemic myocardium. Accumulation of 99m TcO(BAT-NI) in ischaemic heart regions was comparable to that in the liver. Biodistribution studies showed a median uptake of 0.65% ID/g of 99m TcO(BAT-NI) in ischaemic tissue and an I/N of 3.3. On planar images of the thorax and upper abdomen the ischaemic hearts were visualised faintly; the median heart to lung count ratio for 99m TcO(BAT-NI) was 1.7, and the median heart to liver count ratio was 1.0. We conclude that uptake of 99m TcO(BAT-NI) in ischaemic myocardium does not depend on the nitroimidazole moiety but is intrinsic to the BAT complex

  17. Correlation of hypoxia inducible factor-1α and vascular endothelium growth factor in rat myocardium during aerobic and anaerobic exercise

    Directory of Open Access Journals (Sweden)

    Rostika Flora

    2012-08-01

    Full Text Available Background: Exercise increases the need for oxygen to generate ATP through oxidative phosphorylation. If the high energy demand during exercise is not balanced by sufficient oxygen supply, hypoxia occurs in skeletal muscle tissue leading to upregulation of hypoxia inducible factor-1α (HIF-1α. The activity of HIF-1α increases the expression of various genes in order to reduce the metabolic dependence on oxygen and to increase oxygen supply to the tissue, e.g., VEGF which plays a role in angiogenesis. In myocardium, it is unclear whether exercise leads to hypoxia and whether HIF-1α and VEGF play a role in the mechanism of hypoxic adaptation. This study aimed to investigate the correlation of HIF-1α and VEGF in heart muscle tissue of rats during aerobic and anaerobic exercise.Methods: A rat treadmill was used with a specific exercise program for 1, 3, 7 and 10 days. The concentrations of HIF-1α and VEGF were measured the myocardium.Results: Both, HIF-1α protein and VEGF were increased (p < 0.05 in the groups with aerobic and anaerobic exercise. Concentrations of HIF-1α were highest on the first day of activity, being higher in the anaerobic than in the aerobic group (156.8 ± 33.1 vs. 116.03 ± 5.66. Likewise, the highest concentration of VEGF in the group with anaerobic exercise occurred on the first day (36.37 ± 2:35, while in the aerobic group, VEGF concentration was highest on day 3 (40.66 ± 1.73. The correlation between the myocardial tissue consentrations of HIF-1α and VEGF is moderate (r = 0.59 in the aerobic group and strong in the anaerobic group (r = 0.69.Conclusion: Aerobic and anaerobic exercise increase HIF-1α and VEGF concentrations in rat myocardium in specific patterns. The anaerobic condition triggers vascularization stronger and obviously earlier than aerobic exercise. (Med J Indones. 2012;21:133-40Keywords: Exercise, HIF-1α, myocardium, VEGF

  18. Remote Ischaemic PrEconditioning of Human Myocardium (RIPE): study protocol for a double-blinded randomised controlled trial.

    Science.gov (United States)

    Deja, Marek A; Wiaderkiewicz, Ryszard; Czekaj, Piotr; Czech, Ewa; Malinowski, Marcin; Machej, Leszek; Węglarzy, Andrzej; Kowalówka, Adam; Piekarska, Magda; Szurlej, Bartosz; Latusek, Tomasz

    2018-01-01

    Remote preconditioning has been shown to be a potent protective phenomenon in many animals. Several studies aimed to demonstrate it was feasible in humans by trying to show its protective effect during cardiac surgery. Of these, some small studies and one larger trial were positive while two other bigger studies showed no effectiveness of remote preconditioning as assessed by levels of postoperatively released cardiac markers. Recently, two large clinical trials also failed to prove the benefit of remote preconditioning in cardiac surgery. No study showed that remote preconditioning actually increases resistance of human myocardium to standardised ischaemic and reperfusion stimulus in experimental settings. In animal studies, remote preconditioning was shown to improve mitochondrial function and structure, but such data on human myocardium are scarce. The aim of the study is to determine whether remote preconditioning protects human myocardium against ischaemia-reperfusion injury in both in vivo and in vitro conditions. The trial is designed as a single-centre, double-blinded, sham-controlled trial of 120 patients. We randomise (1:1) patients referred for coronary artery bypass grafting for stable coronary artery disease to remote preconditioning or "sham" intervention. The remote preconditioning is obtained by three cycles of 5 min inflation and 5 min deflation of a blood pressure cuff on the right arm. Postoperative course including myocardial enzymes profile will be analysed. Moreover, in the in-vitro arm the clinically preconditioned myocardium will be assessed for function, mitochondria structure, and mitochondria-dependent apoptosis. The informed consent of all patients is obtained before enrolment into the study by the investigator. The study conforms to the spirit and the letter of the declaration of Helsinki. In case the effect of remote preconditioning is not measurable in ex-vivo assessment, any future attempt at implementing this phenomenon in clinical

  19. Identification of viable myocardium in patients with chronic coronary artery disease and left ventricular dysfunction. Comparison of thallium scintigraphy with reinjection and PET imaging with 18F-fluorodeoxyglucose

    International Nuclear Information System (INIS)

    Bonow, R.O.; Dilsizian, V.; Cuocolo, A.; Bacharach, S.L.

    1991-01-01

    In patients with chronic coronary artery disease and left ventricular dysfunction, the distinction between ventricular dysfunction arising from myocardial fibrosis and ischemic, but viable, myocardium has important clinical implications. By positron emission tomography (PET), enhanced fluorine-18-labeled fluorodeoxyglucose (FDG) uptake in myocardial segments with impaired function and reduced blood flow is evidence of myocardial viability. Reinjection of thallium-201 at rest immediately after stress-redistribution imaging may also provide evidence of myocardial viability by demonstrating thallium uptake in regions with apparently irreversible defects. To compare these two methods, we studied 16 patients with chronic coronary artery disease and left ventricular dysfunction, all of whom had irreversible defects on standard exercise-redistribution thallium single-photon emission computed tomography (SPECT) imaging. Thallium was reinjected immediately after the redistribution study, and SPECT images were reacquired. The patients also underwent PET imaging with FDG and oxygen-15-labeled water. A total of 432 myocardial segments were analyzed from comparable transaxial tomograms, of which 166 (38%) had irreversible thallium defects on redistribution images before reinjection. FDG uptake was demonstrated in 121 (73%) of these irreversible defects. Irreversible defects were then subgrouped according to the degree of thallium activity, relative to peak activity in normal regions. Irreversible defects with only mild (60-85% of peak activity) or moderate (50-59% of peak) reduction in thallium activity were considered viable on the basis of FDG uptake in 91% and 84% of these segments, respectively. In contrast, in irreversible defects with severe reduction in thallium activity (less than 50% of peak), FDG uptake was present in 51% of segments

  20. Factors of Formation of Various Types of Left Ventricular Diastolic Filling in Adolescents with Myocardium Pathology

    Directory of Open Access Journals (Sweden)

    L.F. Bogmat

    2016-08-01

    Full Text Available Objective: to study the main components of the formation of impaired left ventricular diastolic filling in adolescents with myocardial pathology. Materials and methods. The study involved 110 adolescents with myocardial pathology aged 13–18 years, of which 40 — with heart rhythm disorder, 40 — with dysplastic cardiomyopathy, 30 — with primary hypertension. Morphological and functional parameters of the heart were studied using ultrasound according to standard procedure. Left ventricular diastolic function has been studied in the pulsed wave Doppler mode with transmitral flow mapping from the apical access of four-chambered heart. For an adequate assessment of left ventricular diastolic function and detection of its earliest disorders, adolescents underwent tests with isometric exercise. Based on these results, adolescents were divided in terms of the E/A ratio. In order to identify common latent factors that explain the correlation between indicators, we have used the factor analysis, namely, the principal component analysis. All statistical procedures were performed using application packages Statgraphics Centurion. Results. On the initial stages of formation of diastolic dysfunction of the left ventricular myocardium in adolescents, a significant role is played by a number of factors, which can be conditionally defined as the geometric, functional and neurohumoral factors consistently included in the pathological process. Thus, during the formation of left ventricular diastolic dysfunction type 1, the number one is neurohumoral factor, namely, the activation of the sympathoadrenal system, then peripheral vascular tone is being involved in the pathological process, and, consequently, a geometric factor — changing the sizes of the left atrium. In the formation of left ventricular diastolic dysfunction type 2, the process consistently involves the renin-angiotensin system, namely, renin, a functional factor is presented by the indices

  1. Diagnostic efficacy of optimised evaluation of planar MIBI myocardium perfusion scintigraphy: a probabilistic approach

    International Nuclear Information System (INIS)

    Kusmierek, J.; Plachcinska, A.

    1999-01-01

    Background: The Bayesian (probabilistic) approach to the results of a diagnostic test appears to be more informative than an interpretation of results in binary terms (having disease or not). The aim of our study was the analysis of the effect of an optimised evaluation of myocardium perfusion scintigrams on the probability of CAD in individual patients. Methods: 197 patients (132 males and 65 females) suspected of CAD, with no history of myocardial infarction were examined. Scintigraphic images were evaluated applying two methods of analysis: visual (semiquantitative) and quantitative, and the combination of both. The sensitivity and specificity of both methods (and their combination) in the detection of CAD were determined and optimal methods of scintigram evaluation, separately for males and females, were selected. All patients were subjected to coronary angiography. The pre-test probability of CAD was assessed according to Diamond (1) and the post-test probability was evaluated in accordance with Bayes's theorem. Patients were divided, according to a pre-test probability of CAD, into 3 groups: with low, medium and high probability of the disease. The same subdivision was made in relation to post-test probability of CAD. The numbers of patients in respective subgroups, before and after the test, were compared. Moreover, in order to test the reliability of post-test probability, its values were compared with real percentages of CAD occurrence among the patients under study, as demonstrated by the angiography. Results: The combination of visual and quantitative methods was accepted as the optimal method of male scintigram evaluation (with sensitivity and specificity equalling 95% and 82%, respectively) and a sole quantitative analysis as the optimal method of female scintigram evaluation (sensitivity and specificity amounted to 81% and 84%, respectively). In the subgroup of males the percentage of individuals with medium pre-test CAD probability equalled 52 and

  2. Regional glucose utilization in infarcted and remote myocardium: its relation to coronary anatomy and perfusion.

    Science.gov (United States)

    Fragasso, G; Chierchia, S L; Landoni, C; Lucignani, G; Rossetti, E; Sciammarella, M; Vanoli, G E; Fazio, F

    1998-07-01

    -revascularized patients of those remote areas which are apparently normally perfused, but show abnormal fasting FDG uptake after myocardial infarction. Such studies may have important implications for the management of post-infarct patients, as the preservation of coronary vasodilator reserve and myocardial metabolism in remote myocardium may be seen as an additional goal in the treatment of such patients.

  3. Hyperventilation and circadian rhythm of the electrical stability of rat myocardium

    Directory of Open Access Journals (Sweden)

    Svorc P

    2013-08-01

    Full Text Available Pavol Svorc,1,2 Alexander Marossy,1 Pavol Svorc Jr2 1Department of Physiology, Medical Faculty, Safarik University, Kosice, Slovak Republic; 2Department of Physiology, Medical Faculty, Ostrava University, Ostrava, Czech Republic Objective: Respiratory alkalosis is an extremely common and complicated problem affecting virtually every organ system where the etiologies may be related to pulmonary or cardiovascular disorders. However, there are only few works describing daytime experiments or synchronization of animals to the external environmental periodicity. The aim of the study is to describe the circadian rhythm of the electrical stability of the heart under hyperventilatory conditions. Methods: Circadian rhythms of the electrical stability of the heart, measured by ventricular arrhythmia threshold ([VAT] measurement in 3 hour intervals, were followed during normal artificial ventilation (40 breaths/minute, tidal volume = 1 mL/100 g; n = 17 and hyperventilation (80 breaths/minute, tidal volume = 2 mL/100 g; n = 7 in pentobarbital (40 mg/kg administered intraperitoneally anesthetized female Wistar rats, after 4 week adaptation on the light/dark regime of 12 hour light/12 hour dark (40%–60% humidity, room temperature of 24°C in cages, two animals/cage with access to food and water ad libitum, with the dark period from 18.00h to 06.00h for 4 weeks. Results: The 24 hour course of the VAT showed the highest susceptibility of the rat ventricular myocardium to arrhythmias between 12.00h and 15.00h, and highest resistance between 19.20h and 00.28h (acrophase −338° in time at 22.53h with confidence intervals −2,880° to −70°, under normoxic conditions. Mesor was 2.59 ± 0.53 mA and amplitude 0.33 ± 0.11 mA. Hyperventilation increased the VAT at each interval of the measurement, but did not change the character of its circadian rhythm. Acrophase was on −40° (02.40h, mesor was increased (2.91 mA, and amplitude was decreased (0.13 m

  4. Reduced myocardial perfusion reserve in myocardium having coronary artery aneurysm of Kawasaki disease

    International Nuclear Information System (INIS)

    Yoon, S. N.; Lee, D. S.; Choi, J. Y.; Kil, H. R.; Jeong, Z. K.; Lee, M. C.; Ko, C. S.

    1997-01-01

    stenosis or aneurysms on CAG, that is normal. It was concluded that decreased perfusion reserve could be found in myocardium having only aneurysmal coronary arteries without stenosis on CAG in Kawasaki disease, and this result imply that epicardial rest flow assessed by CAG was not enough to ensure tissue perfusion enough to cover coronary flow reserve

  5. Ultrasound elastic tensor imaging: comparison with MR diffusion tensor imaging in the myocardium

    Science.gov (United States)

    Lee, Wei-Ning; Larrat, Benoît; Pernot, Mathieu; Tanter, Mickaël

    2012-08-01

    conclusion, we have demonstrated that the fiber orientation estimated by ETI, which assesses the shear wave speed (and thus the stiffness), was comparable to that measured by DTI, which evaluates the preferred direction of water diffusion, and have validated this concept within the myocardium. Moreover, ETI was shown capable of mapping the transmural fiber angles with as few as seven shear wave propagation directions.

  6. Measurement of infarct size and percentage myocardium infarcted in a dog preparation with single photon-emission computed tomography, thallium-201, and indium 111-monoclonal antimyosin Fab

    International Nuclear Information System (INIS)

    Johnson, L.L.; Lerrick, K.S.; Coromilas, J.

    1987-01-01

    Single photon-emission tomography (SPECT) and indium 111-labeled monoclonal antimyosin Fab fragments were used to measure myocardial infarct size in 12 dogs, six subjected to balloon catheter-induced coronary artery occlusion for 6 hr (late reperfusion) and six subjected to occlusion with reperfusion at 2 hr (early reperfusion). Tomographic imaging was performed 24 hr after the intravenous injection of labeled Fab fragments with the use of a dual-head SPECT camera with medium-energy collimators. Immediately after the first tomographic scan, thallium-201 was injected into nine of 12 dogs and imaging was repeated. Estimated infarct size in grams was calculated from transaxially reconstructed, normalized, and background-corrected indium SPECT images with the use of a threshold technique for edge detection. Estimated noninfarcted myocardium in grams was calculated from obliquely reconstructed thallium SPECT images by a similar method. The animals were killed and infarct size in grams and true infarct size as a percentage of total left ventricular myocardial volume were measured by triphenyl tetrazolium chloride staining. Estimated infarct size from indium SPECT images showed an excellent correlation with true infarct size (r = .95, SEE = 4.1 g). Estimated percentage myocardium infarcted was calculated by dividing estimated infarct size from indium images by the sum of estimated infarct size plus estimated noninfarcted myocardium obtained from thallium images. Correlation between the estimated percentage of myocardium infarcted and true percentage of myocardium infarcted was excellent

  7. Coupling of the Functional Stability of Rat Myocardium and Activity of Lipid Peroxidation in Combined Development of Postinfarction Remodeling and Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    S. A. Afanasiev

    2016-01-01

    Full Text Available Coupling of the functional stability of rat myocardium and activity of lipid peroxidation processes in combined development of postinfarction remodeling and diabetes mellitus has been studied. The functional stability of myocardium was studied by means of the analysis of inotropic reaction on extrasystolic stimulus, the degree of left ventricular hypertrophy, and the size of scar zone. It was shown that in combined development of postinfarction cardiac remodeling of heart (PICR with diabetes mellitus (DM animal body weight decreased in less degree than in diabetic rats. Animals with combined pathology had no heart hypertrophy. The amplitude of extrasystolic contractions in rats with PICR combined with DM had no differences compared to the control group. In myocardium of rats with PICR combined with DM postextrasystolic potentiation was observed in contrast with the rats with PICR alone. The rats with combined pathology had the decreased value of TBA-active products. Thus, the results of study showed that induction of DM on the stage of the development of postinfarction remodeling increases adaptive ability of myocardium. It is manifested in inhibition of increase of LPO processes activity and maintaining of force-interval reactions of myocardium connected with calcium transport systems of sarcoplasmic reticulum of cardiomyocytes.

  8. METABOLIC THERAPY IN PATIENTS WITH ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    L. B. Zavaliy

    2018-01-01

    Full Text Available The article shows the world experience of metabolic therapy use in the treatment of ischemic stroke. The issue still remains prominent. The reasonability of prescribing metabolic drugs is not completely clear, its effectiveness has not been fully proved, despite numerous studies which show only trends. The article presents an overview of the most popular drugs of different pharmacological groups with a metabolic effect which affect different parts of the ischemic cascade. Ethylmethylhydroxypyridine succinate and cytoflavin have predominantly antihypoxic effect, improve functional outcome and neurological functions, and normalize overall well-being and adaptation. Cerebrolysin is a complex of low molecular weight biologically active peptides derived from the pig’s brain. It has a multimodal effect on the brain, helps to reduce the volume of cerebral infarction, restores neurologic functions and improves the functional outcome. Cortexin is a mixture of cattle brain polypeptides, also has a complex action that provides the most complete reversion of neurological deficit, improves cognitive functions and the functional outcome, reduces the level of paroxysmal convulsive readiness and improves bioelectric activity of the brain. Citicoline is a precursor of cell membrane key ultrastructures, contributes to significant reduction in the volume of cortical brain damage, improves cholinergic transmission, which results in better clinical outcome, even despite the questionable impact on the neurological status. Choline Alfoscerate is a precursor of choline, and the use of the drug significantly limits the growth of the cerebral infarction area starting from the first day of therapy, leads to reversion of neurological symptoms and achievement of rehabilitation goals. Actovegin is deproteinized derivative of calf blood, activates metabolism in tissues, improves trophism and stimulates regeneration. In a large study, it was shown that Actovegin improved

  9. Minimal Poems Written in 1979 Minimal Poems Written in 1979

    Directory of Open Access Journals (Sweden)

    Sandra Sirangelo Maggio

    2008-04-01

    Full Text Available The reading of M. van der Slice's Minimal Poems Written in 1979 (the work, actually, has no title reminded me of a book I have seen a long time ago. called Truth, which had not even a single word printed inside. In either case we have a sample of how often excentricities can prove efficient means of artistic creativity, in this new literary trend known as Minimalism. The reading of M. van der Slice's Minimal Poems Written in 1979 (the work, actually, has no title reminded me of a book I have seen a long time ago. called Truth, which had not even a single word printed inside. In either case we have a sample of how often excentricities can prove efficient means of artistic creativity, in this new literary trend known as Minimalism.

  10. Is opium addiction a risk factor for ischemic heart disease and ischemic stroke?

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Rezvani

    2012-01-01

    Full Text Available Background: The main source of studies about effects of opium consumption on heart and brain attacks originates from Iran Therefore the aim of the present study was to assess opium addiction as a probable influencing factor for ischemic heart disease and ischemic stroke. Materials and Methods: A cross-sectional study was carried out in two Cardiology and Neurology clinics in Eastern Iran in 2011. Diagnosis of Ischemic Heart Disease (IHD and Ischemic Stroke (IS was made by Cardiologist and Stroke Neurologist respectively. The influence of gender, hypertension, diabetes, hyperlipidemia, cigarette smoking, oral and inhaled opium consumption on distribution of IHD and IS were evaluated. Results: Five hundred fifty eight patients (307 females, 251 males with mean age 56.2 years enrolled the study. On adjusted odds ratios of our whole 558 patients, only hypertension and diabetes had a significant influence on occurrence of IHD; (P = 0.000 and P = 0.000 respectively. Oral and inhaled routes of opium addiction did not have a significant effect on occurrence of IHD; [OR = 1.172, 95% CI = 0.624-2.203, P = 0.621] and [OR = 1.820, 95% CI = 0.811-4.085, P = 0.147] respectively. Hypertension and diabetes were significant risk factors of IS in our 558 patients at multivariate analysis; (P = 0.000, P = 0.020. Oral opium addiction was as significant protective factor of IS in our study group; OR = 0.211, 95% CI = 0.079-0.564, P = 0.002, while inhaled opium addiction did not have a significant effect on occurrence of IS in our patients at; OR = 1.760, 95% CI = 0.760-4.076, P = 0.187. Conclusion: Oral opium consumption is a protective factor of IS but not IHD. Inhaled opium addiction does not have a significant influence on occur r ence of IS and IHD.

  11. Is opium addiction a risk factor for ischemic heart disease and ischemic stroke?

    Science.gov (United States)

    Rezvani, Mohammad Reza; Ghandehari, Kavian

    2012-10-01

    The main source of studies about effects of opium consumption on heart and brain attacks originates from Iran Therefore the aim of the present study was to assess opium addiction as a probable influencing factor for ischemic heart disease and ischemic stroke. A cross-sectional study was carried out in two Cardiology and Neurology clinics in Eastern Iran in 2011. Diagnosis of Ischemic Heart Disease (IHD) and Ischemic Stroke (IS) was made by Cardiologist and Stroke Neurologist respectively. The influence of gender, hypertension, diabetes, hyperlipidemia, cigarette smoking, oral and inhaled opium consumption on distribution of IHD and IS were evaluated. Five hundred fifty eight patients (307 females, 251 males) with mean age 56.2 years enrolled the study. On adjusted odds ratios of our whole 558 patients, only hypertension and diabetes had a significant influence on occurrence of IHD; (P = 0.000 and P = 0.000) respectively. Oral and inhaled routes of opium addiction did not have a significant effect on occurrence of IHD; [OR = 1.172, 95% CI = 0.624-2.203, P = 0.621] and [OR = 1.820, 95% CI = 0.811-4.085, P = 0.147] respectively. Hypertension and diabetes were significant risk factors of IS in our 558 patients at multivariate analysis; (P = 0.000, P = 0.020). Oral opium addiction was as significant protective factor of IS in our study group; OR = 0.211, 95% CI = 0.079-0.564, P = 0.002, while inhaled opium addiction did not have a significant effect on occurrence of IS in our patients at; OR = 1.760, 95% CI = 0.760-4.076, P = 0.187. Oral opium consumption is a protective factor of IS but not IHD. Inhaled opium addiction does not have a significant influence on occurrence of IS and IHD.

  12. Predictors of ischemic versus hemorrhagic strokes in hypertensive patients

    International Nuclear Information System (INIS)

    Khealani, B.A.; Syed, N.A.; Maken, S.; Mapari, U.U.; Hameed, B.; Ali, S.; Qureshi, R.; Akhter, N.; Hassan, A.; Sonawalla, A.B.; Baig, S.M.; Wasay, M.

    2005-01-01

    Objective: To identify the factors that predispose to ischemic versus hemorrhagic stroke in hypertensive patients. Materials and Methods: All the hypertensive patients, who were registered in AKUH acute stroke outcome data base, over a period of 22 months, were identified and from this cohort the patients with first ever stroke were selected. The data regarding demographics, stroke type (ischemic vs. hemorrhagic), pre-existing medical problems, laboratory and radiological investigations was recorded and analyzed. Results: Five hundred and nineteen patients with either ischemic stroke or parenchymal hemorrhage were registered over a period of 22 months. Three hundred and forty-eight patients (67%) had hypertension and of these, 250 had first ever stroke at the time of admission. Presence of diabetes mellitus (OR: 3.76; Cl:1.67-8.46) and ischemic heart disease (OR: 6.97; Cl:1.57-30.98) were found to be independent predictors of ischemic strokes. Conclusion: Presence of diabetes mellitus and ischemic heart disease predict ischemic stroke in a patient with hypertension. (author)

  13. Plasma Magnesium and the Risk of Ischemic Stroke among Women

    Science.gov (United States)

    Akarolo-Anthony, Sally N.; Jiménez, Monik C.; Chiuve, Stephanie E.; Spiegelman, Donna; Willett, Walter C.; Rexrode, Kathryn M.

    2014-01-01

    Background and Purpose Lower plasma magnesium levels may be associated with higher blood pressure and endothelial dysfunction, but sparse prospective data are available for stroke. Methods Among 32,826 participants in the Nurses’ Health Study who provided blood samples in 1989–1990, incident ischemic strokes were identified and confirmed by medical records through 2006. We conducted a nested case-control analysis of 459 cases, matched 1:1 to controls on age, race/ethnicity, smoking status, date of blood draw, fasting status, menopausal status and hormone use. We used conditional logistic regression models to estimate the multivariable adjusted association of plasma magnesium and the risk of ischemic stroke and ischemic stroke subtypes. Results Median magnesium levels did not differ between ischemic stroke cases and controls (median=0.86 mmol/l for both; p-value=0.14). Conditional on matching factors, women in the lowest magnesium quintile had a relative risk (RR) of 1.34 (95% confidence interval [CI]: 0.86–2.10, p trend=0.13) for total ischemic stroke, compared to women in the highest quintile. Additional adjustment for risk factors and confounders did not substantially alter the risk estimates for total ischemic stroke. Women with magnesium levels magnesium levels ≥0.82 mmol/l. No significant effect modification was observed by age, body mass index, hypertension or diabetes. Conclusions Lower plasma magnesium levels may contribute to higher risk of ischemic stroke among women. PMID:25116874

  14. Correlation study on cystatin C and ischemic stroke

    Directory of Open Access Journals (Sweden)

    CHEN Rong-bo

    2013-06-01

    Full Text Available Objective To investigate the relationship between serum cystatin C (Cys C and patients with acute ischemic stroke. Methods The clinical and laboratory data of 115 patients with acute ischemic stroke and 110 controls were recorded and analyzed. Results The serum Cys C levels of patients in ischemic stroke group [(1.15 ± 0.34 mg/L] were higher than that of the control group [(0.99 ± 0.25 mg/L]. The difference between two groups was significant after correction of age and cardiovascular risk factors (t = ? 3.889, P = 0.000. It was found that age, Cys C, homocysteine (Hcy, type 2 diabetes mellitus [hemoglobin A1c (HbA1c, fructosamine (FRU], smoking, alcohol consumption, hypertension and intima-media thickness (IMT were risk factors for ischemic stroke on univariate Logistic regression analysis. The difference of serum Cys C level between the patients and controls was significant (P = 0.000, but through covariance analysis, after adjusted other risk factors, it was not significant (P = 0.875. Conclusion The serum Cys C levels of patients in ischemic stroke group is higher than the control group. It can be used as an indicator in the acute phase of ischemic stroke. The elevation of serum Cys C is a risk factor for ischemic stroke, but not an independent risk factor.

  15. Imaging of cerebral ischemic edema and neuronal death

    Energy Technology Data Exchange (ETDEWEB)

    Kummer, Ruediger von [Universitaetsklinikum Carl Gustav Carus, Institut fuer Diagnostische und Interventionelle Neuroradiologie, Dresden (Germany); Dzialowski, Imanuel [Elblandklinikum Meissen, Neurologische Rehabilitationsklinik Grossenhain, Meissen (Germany)

    2017-06-15

    In acute cerebral ischemia, the assessment of irreversible injury is crucial for treatment decisions and the patient's prognosis. There is still uncertainty how imaging can safely differentiate reversible from irreversible ischemic brain tissue in the acute phase of stroke. We have searched PubMed and Google Scholar for experimental and clinical papers describing the pathology and pathophysiology of cerebral ischemia under controlled conditions. Within the first 6 h of stroke onset, ischemic cell injury is subtle and hard to recognize under the microscope. Functional impairment is obvious, but can be induced by ischemic blood flow allowing recovery with flow restoration. The critical cerebral blood flow (CBF) threshold for irreversible injury is ∝15 ml/100 g x min. Below this threshold, ischemic brain tissue takes up water in case of any residual capillary flow (ionic edema). Because tissue water content is linearly related to X-ray attenuation, computed tomography (CT) can detect and measure ionic edema and, thus, determine ischemic brain infarction. In contrast, diffusion-weighted magnetic resonance imaging (DWI) detects cytotoxic edema that develops at higher thresholds of ischemic CBF and is thus highly sensitive for milder levels of brain ischemia, but not specific for irreversible brain tissue injury. CT and MRI are complimentary in the detection of ischemic stroke pathology and are valuable for treatment decisions. (orig.)

  16. Neurosteroids and Ischemic Stroke: Progesterone a Promising Agent in Reducing the Brain Injury in Ischemic Stroke.

    Science.gov (United States)

    Andrabi, Syed Suhail; Parvez, Suhel; Tabassum, Heena

    2017-01-01

    Progesterone (P4), a well-known neurosteroid, is produced by ovaries and placenta in females and by adrenal glands in both sexes. Progesterone is also synthesized by central nervous system (CNS) tissues to perform various vital neurological functions in the brain. Apart from performing crucial reproductive functions, it also plays a pivotal role in neurogenesis, regeneration, cognition, mood, inflammation, and myelination in the CNS. A substantial body of experimental evidence from animal models documents the neuroprotective role of P4 in various CNS injury models, including ischemic stroke. Extensive data have revealed that P4 elicits neuroprotection through multiple mechanisms and systems in an integrated manner to prevent neuronal and glial damage, thus reducing mortality and morbidity. Progesterone has been described as safe for use at the clinical level through different routes in several studies. Data regarding the neuroprotective role of P4 in ischemic stroke are of great interest due to their potential clinical implications. In this review, we succinctly discuss the biosynthesis of P4 and distribution of P4 receptors (PRs) in the brain. We summarize our work on the general mechanisms of P4 mediated via the modulation of different PR and neurotransmitters. Finally, we describe the neuroprotective mechanisms of P4 in ischemic stroke models and related clinical prospects.

  17. Minimal Flavour Violation and Beyond

    CERN Document Server

    Isidori, Gino

    2012-01-01

    We review the formulation of the Minimal Flavour Violation (MFV) hypothesis in the quark sector, as well as some "variations on a theme" based on smaller flavour symmetry groups and/or less minimal breaking terms. We also review how these hypotheses can be tested in B decays and by means of other flavour-physics observables. The phenomenological consequences of MFV are discussed both in general terms, employing a general effective theory approach, and in the specific context of the Minimal Supersymmetric extension of the SM.

  18. Minimizing waste in environmental restoration

    International Nuclear Information System (INIS)

    Thuot, J.R.; Moos, L.

    1996-01-01

    Environmental restoration, decontamination and decommissioning, and facility dismantlement projects are not typically known for their waste minimization and pollution prevention efforts. Typical projects are driven by schedules and milestones with little attention given to cost or waste minimization. Conventional wisdom in these projects is that the waste already exists and cannot be reduced or minimized; however, there are significant areas where waste and cost can be reduced by careful planning and execution. Waste reduction can occur in three ways: beneficial reuse or recycling, segregation of waste types, and reducing generation of secondary waste

  19. Minimizing waste in environmental restoration

    International Nuclear Information System (INIS)

    Moos, L.; Thuot, J.R.

    1996-01-01

    Environmental restoration, decontamination and decommissioning and facility dismantelment projects are not typically known for their waste minimization and pollution prevention efforts. Typical projects are driven by schedules and milestones with little attention given to cost or waste minimization. Conventional wisdom in these projects is that the waste already exists and cannot be reduced or minimized. In fact, however, there are three significant areas where waste and cost can be reduced. Waste reduction can occur in three ways: beneficial reuse or recycling; segregation of waste types; and reducing generation of secondary waste. This paper will discuss several examples of reuse, recycle, segregation, and secondary waste reduction at ANL restoration programs

  20. Post-ischemic bowel stricture: CT features in eight cases

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Sil [Dept. of Radiology, College of Medicine, Ewha Womans University, Mokdong Hospital, Seoul (Korea, Republic of); Kim, Hyun Jin; Hong, Sung Mo; Park, Seong Ho; Lee, Jong Seok; Kim, Ah Young; Ha, Hyun Kwon [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2017-11-15

    To investigate the characteristic radiologic features of post-ischemic stricture, which can then be implemented to differentiate that specific disease from other similar bowel diseases, with an emphasis on computed tomography (CT) features. Eight patients with a diagnosis of ischemic bowel disease, who were also diagnosed with post-ischemic stricture on the basis of clinical or pathologic findings, were included. Detailed clinical data was collected from the available electronic medical records. Two radiologists retrospectively reviewed all CT images. Pathologic findings were also analyzed. The mean interval between the diagnosis of ischemic bowel disease and stricture formation was 57 days. The severity of ischemic bowel disease was variable. Most post-ischemic strictures developed in the ileum (n = 5), followed by the colon (n = 2) and then the jejunum (n = 1). All colonic strictures developed in the “watershed zone.” The pathologic features of post-ischemic stricture were deep ulceration, submucosal/subserosal fibrosis and chronic transmural inflammation. The mean length of the post-ischemic stricture was 7.4 cm. All patients in this study possessed one single stricture. On contrast-enhanced CT, most strictures possessed concentric wall thickening (87.5%), with moderate enhancement (87.5%), mucosal enhancement (50%), or higher enhancement in portal phase than arterial phase (66.7%). Post-ischemic strictures develop in the ileum, jejunum and colon after an interval of several weeks. In the colonic segment, strictures mainly occur in the “watershed zone.” Typical CT findings include a single area of concentric wall thickening of medium length (mean, 7.4 cm), with moderate and higher enhancement in portal phase and vasa recta prominence.

  1. Remnant cholesterol and ischemic heart disease

    DEFF Research Database (Denmark)

    Varbo, Anette; Nordestgaard, Børge G

    2014-01-01

    PURPOSE OF REVIEW: To review recent advances in the field of remnant cholesterol as a contributor to the development of ischemic heart disease (IHD). RECENT FINDINGS: Epidemiologic, mechanistic, and genetic studies all support a role for elevated remnant cholesterol (=cholesterol in triglyceride......-rich lipoproteins) as a contributor to the development of atherosclerosis and IHD. Observational studies show association between elevated remnant cholesterol and IHD, and mechanistic studies show remnant cholesterol accumulation in the arterial wall like LDL-cholesterol (LDL-C) accumulation. Furthermore, large...... genetic studies show evidence of remnant cholesterol as a causal risk factor for IHD independent of HDL-cholesterol levels. Genetic studies also show that elevated remnant cholesterol is associated with low-grade inflammation, whereas elevated LDL-C is not. There are several pharmacologic ways of lowering...

  2. Critical care management of acute ischemic stroke.

    Science.gov (United States)

    Coplin, William M

    2012-06-01

    Acute ischemic stroke (AIS) can have profound and devastating effects on the CNS and several other organs. Approximately 15% to 20% of patients with AIS are admitted to an intensive care unit and cared for by a multidisciplinary team. This article discusses the critical care management of patients with AIS. Patients with AIS require attention to airway, pulmonary status, blood pressure, glucose, temperature, cardiac function, and, sometimes, life-threatening cerebral edema. The lack of disease-specific data has led to numerous management approaches and limited guidance on choosing among them. Existing guidelines emphasize risk factors, prevention, natural history, and prevention of bleeding but provide little discussion of the complex critical care issues involved in caring for patients with AIS.

  3. Use of nitrates in ischemic heart disease.

    Science.gov (United States)

    Giuseppe, Cocco; Paul, Jerie; Hans-Ulrich, Iselin

    2015-01-01

    Short-acting nitrates are beneficial in acute myocardial ischemia. However, many unresolved questions remain about the use of long-acting nitrates in stable ischemic heart disease. The use of long-acting nitrates is weakened by the development of endothelial dysfunction and tolerance. Also, we currently ignore whether lower doses of transdermal nitroglycerin would be better than those presently used. Multivariate analysis data from large nonrandomized studies suggested that long-acting nitrates increase the incidence of acute coronary syndromes, while data from another multivariate study indicate that they have positive effects. Because of methodological differences and open questions, the two studies cannot be compared. A study in Japanese patients with vasospastic angina has shown that, when compared with calcium antagonists, long-acting nitrates do not improve long-term prognosis and that the risk for cardiac adverse events increases with the combined therapy. We have many unanswered questions.

  4. Citicoline for ischemic stroke: ICTUS trial

    Directory of Open Access Journals (Sweden)

    Vladimir Anatolyevich Parfenov

    2012-01-01

    Full Text Available The paper gives data available in the literature on the use of citicoline in an experimental model of ischemic stroke (IS and in randomized multicenter placebo-controlled trials. It analyzes the results of the ICTUS trial in which 2298 patients with IS who received randomly citicoline or placebo for 24 hours after the onset of symptoms (I000 mg intravenously every I2 hours during the first 3 days, then orally as one 500-mg tablet every 12 hours during 6 weeks. The results of the trial confirmed the safety of citicoline used in IS, but failed to show its significant advantage over placebo in reducing the degree of disability (global improvement 90 days later. However, to pool the results of the ICTUS trial with those of other randomized multicenter placebo-controlled studies demonstrates a significant decrease in the degree of disability in IS patients treated with citicoline.

  5. Metabolically Healthy Obesity and Ischemic Heart Disease

    DEFF Research Database (Denmark)

    Hansen, Louise; Netterstrom, Marie K.; Johansen, Nanna B.

    2017-01-01

    Context: Recent studies have suggested that a subgroup of obese individuals is not at increased risk of obesity-related complications. This subgroup has been referred to as metabolically healthy obese. Objective: To investigate whether obesity is a risk factor for development of ischemic heart...... risk factors (low high-density lipoprotein cholesterol, elevated blood pressure, triglycerides, and fasting plasma glucose). Metabolically healthy individuals were defined as having no metabolic risk factors, and metabolically unhealthy individuals were defined as having a minimum of one. Main Outcome...... Measures: IHD. Results: During follow-up, 323 participants developed IHD. Metabolically healthy obese men had increased risk of IHD compared with metabolically healthy normal-weight men [hazard ratio (HR), 3.1; 95% confidence interval (CI), 1.1 to 8.2)]. The corresponding results for women were less...

  6. Targeting Neovascularization in Ischemic Retinopathy: Recent Advances

    Science.gov (United States)

    Al-Shabrawey, Mohamed; Elsherbiny, Mohamed; Nussbaum, Julian; Othman, Amira; Megyerdi, Sylvia; Tawfik, Amany

    2014-01-01

    Pathological retinal neovascularization (RNV) is a common micro-vascular complication in several retinal diseases including retinopathy of prematurity, diabetic retinopathy, age-related macular degeneration and central vein occlusion. The current therapeutic modalities of RNV are invasive and although they may slow or halt the progression of the disease they are unlikely to restore normal acuity. Therefore, there is an urgent need to develop treatment modalities, which are less invasive and therefore associated with fewer procedural complications and systemic side effects. This review article summarizes our understanding of the pathophysiology and current treatment of RNV in ischemic retinopathies; lists potential therapeutic targets; and provides a framework for the development of future treatment modalities. PMID:25598837

  7. [Secondary prevention of ischemic non cardioembolic stroke].

    Science.gov (United States)

    Armario, Pedro; Pinto, Xavier; Soler, Cristina; Cardona, Pere

    2015-01-01

    Stroke patients are at high risk for recurrence or new occurrence of other cardiovascular events or cardiovascular mortality. It is estimated that a high percentage of non-cardioembolic ischemic stroke can be prevented by a suitable modification of lifestyle (diet and exercise), reducing blood pressure (BP) with antihypertensive medication, platelet aggregation inhibitors, statins and high intake reducing consumption of. Unfortunately the degree of control of the different risk factors in secondary prevention of stroke is low. The clinical practice guidelines show clear recommendations with corresponding levels of evidence, but only if implemented in a general way they will get a better primary and secondary stroke prevention. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  8. Acute ischemic stroke. Imaging and intervention

    International Nuclear Information System (INIS)

    Gonzalez, R.G.; Lev, M.H.; Hirsch, J.A.; Koroshetz, W.J.; Schaefer, P.

    2006-01-01

    This timely book provides basic, practical and up-to-date information on how to use imaging to diagnose and treat patients with acute ischemic stroke. Written by physicians from the Massachusetts General Hospital and faculty from the Harvard Medical School, the book distills years of experience in the day-to-day management of acute stroke patients, as well as leading-edge basic and clinical research, into a practical guide. With the growing awareness that modern CT and MR imaging can meaningfully improve the outcome of the acute stroke patient, this book provides the practical information to advance the capacities of providers in delivering the most advanced care for this disease. (orig.)

  9. Hypertension and Ischemic Heart Disease in Women.

    Science.gov (United States)

    Dorobantu, Maria; Onciul, Sebastian; Tautu, Oana Florentina; Cenko, Edina

    2016-01-01

    Ischemic heart disease (IHD) is the most important cause of mortality worldwide. Although the awareness of cardiovascular risk factors and IHD in women has increased over the last decades, mortality rates are still higher in women than in men. Among traditional cardiovascular risk factors, hypertension is associated with a greater risk for IHD in women as compared to men. In this review, discuss gender differences in epidemiology and pathophysiology of hypertension and its impact on the incidence and outcomes of IHD in women. We also, discuss some "women conditions" such as hypertensive disorders in pregnancy (HDP) and polycystic ovarian syndrome (PCOS). Even though this is not a systematic review, English-language studies on MEDLINE and the Cochrane Database of Systematic reviews were searched for consultation and analysis. Hypertension display different epidemiological patterns in men and women. Studies have shown that hypertension has a different proatherogenic effects in men and women. Hypertension has a direct effect on microcirculation, but estrogens have a protective role in this regard in premenopausal women. However, after the decline in estrogen levels, women are exposed to the same cardiovascular risk as males. Postmenopausal women exhibit a greater burden of cardiovascular risk factors, which together with microvascular dysfunction and smaller and stiffer arteries conducts to the worse prognosis observed in women with IHD. "Women specific conditions" such as HDP and PCOS affects 10% of pregnant women and women in reproductive age, respectively. These conditions are associated with increased risk of hypertension and IHD later in life. Although women are more aware of their hypertension, cardiovascular mortality is higher in hypertensive women with comorbid IHD. Yet these gender disparities in outcomes seem to be attenuated with effective therapy. The pathophysiology of IHD is gender specific, women with ischemic symptoms presenting less often with

  10. Protective effects of ischemic postconditioning on intestinal

    Directory of Open Access Journals (Sweden)

    DING Jun-tao

    2011-04-01

    Full Text Available 【Abstract】Objective: To explore the protective effects of two types of ischemic postconditioning (IP on intestinal mucosa barrier in rabbits with crush injury of the hind limb. Methods: This study was conducted between August and December 2008 in the Department of Trauma Surgery, Daping Hospital, Third Military Medical University, Chongqing, China. The model of crush injury to the hind limb of rabbits was firstly developed by a 25 kg object with the right hind limbs fixed by wooden splints, and then two types of IP were established, including occluding/opening the common iliac artery and vein alternatively (traditional IP, IP A and binding/loosening the proximum of the injured hind limb alternatively (modified IP, IP B. Thirty-six male New Zealand white rabbits were randomly divided into three groups: IP A group, IP B group and control group, with 12 rabbits in each group. The serum levels of diamine oxidase (DAO and intestinal fatty acid-binding protein (I-FABP were detected at 2, 6, 12 and 24 hours after injury. Pathological changes of ileum were examined at 24 hours after injury. Results: The serum levels of I-FABP at 2, 6, 12 and 24 hours after injury in both IP A and IP B groups had a significant decrease, compared with control group. DAO levels also showed the same change trend at 2 and 6 hours after injury, but showed no significant difference between two IP groups. No difference in pathological changes of ileum was found among the three groups. Conclusions: IP can protect intestinal mucosa barrier function on the model of hind limb crush injury in rabbits. Meanwhile the modified IP B shows the same protection as the traditional IP A, and is worth applying in clinic. Key words: Ischemic postconditioning; Crush syndrome; Intestinal mucosa

  11. Severe ischemic colitis following olanzapine use: a Case Report

    Directory of Open Access Journals (Sweden)

    Samuel Raimundo Fernandes

    Full Text Available Ischemic colitis is the most common subtype of intestinal ischemia usually resulting from vasospasm, vessel occlusion or mesenteric hypoperfusion. Neuroleptics have seldom been linked to ischemic colitis by blocking peripheral anticholinergic and antiserotonergic receptors inducing severe gastrointestinal paresis. We report a young patient with severe ischemic colitis requiring surgery due to necrosis of the bowel. After exclusion of other potential causes, olanzapine was admitted as the cause of ischemia. Clinicians should be aware of how to recognize and treat the potentially life-threatening effects of neuroleptics.

  12. Ketogenic Diet Provides Neuroprotective Effects against Ischemic Stroke Neuronal Damages

    Directory of Open Access Journals (Sweden)

    Sheida Shaafi

    2014-12-01

    Full Text Available Ischemic stroke is a leading cause of death and disability in the world. Many mechanisms contribute in cell death in ischemic stroke. Ketogenic diet which has been successfully used in the drug-resistant epilepsy has been shown to be effective in many other neurologic disorders. The mechanisms underlying of its effects are not well studied, but it seems that its neuroprotective ability is mediated at least through alleviation of excitotoxicity, oxidative stress and apoptosis events. On the basis of these mechanisms, it is postulated that ketogenic diet could provide benefits to treatment of cerebral ischemic injuries.

  13. Urgent intra-arterial thrombolytic therapy for acute ischemic stroke

    International Nuclear Information System (INIS)

    Jin Zhengyu; Zhang Qing; Huang Yining; Cui Liying; Yang Ning; Liu Wei; Pan Jie; Gao Shan; Ye Jian; Xu Weihai; Liu Fangjian; Wang Leying; Chen Jun; Dai Jianping

    2002-01-01

    Objective: The authors report the results of urgent intra-arterial thrombolysis (IAT) in patients within 6 h of acute ischemic stroke onset. The purpose of the study was to observe the safety and efficacy of IAT and to analysis the predictive factors related to the outcome. Methods: 25 patients were treated by IAT using urokinase (UK) or recombinant Streptokinase (r-SK) in Union hospital. Primary neuroradiological assessment was performed with CT in all patients. Mechanical disruption of clot remnants was attempted after UK or r-SK was infused. Angiographic recanalization was classified according to Thrombolysis In Myocardial Infarction (TIMI) grades. Clinical outcome was classified as good for Modified Rankin Scale (MRS) scores of 0 to 3 and poor for MRS scores of 4 to 6. Results: There are 18(72%) of patients TIMI 0-1 and 7(28%) patients TIMI 2 before thrombolysis was performed. The rates of complete/partial recanalization just after infusion were 72%, minimal or no recanalization were 28%. 18(72%) of the 25 patients had good outcome, 7(28%) had poor outcome. Cerebral hemorrhage occurred in 4 of the 25 patients, all with poor outcome. Conclusion: Intra-arterial thrombolysis (IAT) is feasible and safe in the setting of acute stroke. Collateral circulation, recanalization and improvement by 4 or more points on NIHSSS within 24 hours were significantly associated with good outcome, there was significantly association between no recanalization and cerebral hemorrhage and death. The key to improve the effect of IAT was successful recanalization

  14. Sludge minimization technologies - an overview

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, Hallvard

    2003-07-01

    The management of wastewater sludge from wastewater treatment plants represents one of the major challenges in wastewater treatment today. The cost of the sludge treatment amounts to more that the cost of the liquid in many cases. Therefore the focus on and interest in sludge minimization is steadily increasing. In the paper an overview is given for sludge minimization (sludge mass reduction) options. It is demonstrated that sludge minimization may be a result of reduced production of sludge and/or disintegration processes that may take place both in the wastewater treatment stage and in the sludge stage. Various sludge disintegration technologies for sludge minimization are discussed, including mechanical methods (focusing on stirred ball-mill, high-pressure homogenizer, ultrasonic disintegrator), chemical methods (focusing on the use of ozone), physical methods (focusing on thermal and thermal/chemical hydrolysis) and biological methods (focusing on enzymatic processes). (author)

  15. Wilson loops in minimal surfaces

    International Nuclear Information System (INIS)

    Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

    1999-01-01

    The AdS/CFT correspondence suggests that the Wilson loop of the large N gauge theory with N = 4 supersymmetry in 4 dimensions is described by a minimal surface in AdS 5 x S 5 . The authors examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which the authors call BPS loops, whose expectation values are free from ultra-violet divergence. They formulate the loop equation for such loops. To the extent that they have checked, the minimal surface in AdS 5 x S 5 gives a solution of the equation. The authors also discuss the zig-zag symmetry of the loop operator. In the N = 4 gauge theory, they expect the zig-zag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. They will show how this is realized for the minimal surface

  16. Classical strings and minimal surfaces

    International Nuclear Information System (INIS)

    Urbantke, H.

    1986-01-01

    Real Lorentzian forms of some complex or complexified Euclidean minimal surfaces are obtained as an application of H.A. Schwarz' solution to the initial value problem or a search for surfaces admitting a group of Poincare transformations. (Author)

  17. Minimal Gromov-Witten rings

    International Nuclear Information System (INIS)

    Przyjalkowski, V V

    2008-01-01

    We construct an abstract theory of Gromov-Witten invariants of genus 0 for quantum minimal Fano varieties (a minimal class of varieties which is natural from the quantum cohomological viewpoint). Namely, we consider the minimal Gromov-Witten ring: a commutative algebra whose generators and relations are of the form used in the Gromov-Witten theory of Fano varieties (of unspecified dimension). The Gromov-Witten theory of any quantum minimal variety is a homomorphism from this ring to C. We prove an abstract reconstruction theorem which says that this ring is isomorphic to the free commutative ring generated by 'prime two-pointed invariants'. We also find solutions of the differential equation of type DN for a Fano variety of dimension N in terms of the generating series of one-pointed Gromov-Witten invariants

  18. Wilson loops and minimal surfaces

    International Nuclear Information System (INIS)

    Drukker, Nadav; Gross, David J.; Ooguri, Hirosi

    1999-01-01

    The AdS-CFT correspondence suggests that the Wilson loop of the large N gauge theory with N=4 supersymmetry in four dimensions is described by a minimal surface in AdS 5 xS 5 . We examine various aspects of this proposal, comparing gauge theory expectations with computations of minimal surfaces. There is a distinguished class of loops, which we call BPS loops, whose expectation values are free from ultraviolet divergence. We formulate the loop equation for such loops. To the extent that we have checked, the minimal surface in AdS 5 xS 5 gives a solution of the equation. We also discuss the zigzag symmetry of the loop operator. In the N=4 gauge theory, we expect the zigzag symmetry to hold when the loop does not couple the scalar fields in the supermultiplet. We will show how this is realized for the minimal surface. (c) 1999 The American Physical Society

  19. Pre-Ischemic Treadmill Training for Prevention of Ischemic Brain Injury via Regulation of Glutamate and Its Transporter GLT-1

    Directory of Open Access Journals (Sweden)

    Jingchun Guo

    2012-07-01

    Full Text Available Pre-ischemic treadmill training exerts cerebral protection in the prevention of cerebral ischemia by alleviating neurotoxicity induced by excessive glutamate release following ischemic stroke. However, the underlying mechanism of this process remains unclear. Cerebral ischemia-reperfusion injury was observed in a rat model after 2 weeks of pre-ischemic treadmill training. Cerebrospinal fluid was collected using the microdialysis sampling method, and the concentration of glutamate was determined every 40 min from the beginning of ischemia to 4 h after reperfusion with high-performance liquid chromatography (HPLC-fluorescence detection. At 3, 12, 24, and 48 h after ischemia, the expression of the glutamate transporter-1 (GLT-1 protein in brain tissues was determined by Western blot respectively. The effect of pre-ischemic treadmill training on glutamate concentration and GLT-1 expression after cerebral ischemia in rats along with changes in neurobehavioral score and cerebral infarct volume after 24 h ischemia yields critical information necessary to understand the protection mechanism exhibited by pre-ischemic treadmill training. The results demonstrated that pre-ischemic treadmill training up-regulates GLT-1 expression, decreases extracellular glutamate concentration, reduces cerebral infarct volume, and improves neurobehavioral score. Pre-ischemic treadmill training is likely to induce neuroprotection after cerebral ischemia by regulating GLT-1 expression, which results in re-uptake of excessive glutamate.

  20. Effect of vanadate and of removal of extracellular Ca2+ and Na+ on tension development and 45Ca efflux in rat and frog myocardium

    DEFF Research Database (Denmark)

    Gesser, H; Bonefeld-Jørgensen, Eva Cecilie

    1983-01-01

    Vanadate in the range 0-5 mM has positive inotropic effects on myocardial strips of frog and to a lesser extent on those of rat. Inhibiting the sarcolemmal Na+, Ca2+ exchange by a solution free of Ca2+ and Na+ caused a drop in 45Ca efflux and a transient increase in resting tension. These effects...... were more expressed for the frog than for the rat myocardium, which suggests that the Na+ for Ca2+ exchange across the cell membrane is more important in the frog than in the rat myocardium. A subsequent addition of vanadate at 2 or 5 mM had no effect on 45Ca efflux, while it increased the resting...... tension. This increase was higher for the frog than for the rat myocardium. These results suggest that the inotropic effects of vanadate may be due to an effect on membrane-bound Ca2+-ATPase....

  1. Pathological prolongation of action potential duration as a cause of the reduced alpha-adrenoceptor-mediated negative inotropy in streptozotocin-induced diabetic mice myocardium.

    Science.gov (United States)

    Kanae, Haruna; Hamaguchi, Shogo; Wakasugi, Yumi; Kusakabe, Taichi; Kato, Keisuke; Namekata, Iyuki; Tanaka, Hikaru

    2017-11-01

    Effect of pathological prolongation of action potential duration on the α-adrenoceptor-mediated negative inotropy was studied in streptozotocin-induced diabetic mice myocardium. In streptozotocin-treated mouse ventricular myocardium, which had longer duration of action potential than that in control mice, the negative inotropic response induced by phenylephrine was smaller than that in control mice. 4-Aminopyridine prolonged the action potential duration and decreased the negative inotropy in control mice. Cromakalim shortened the action potential duration and increased the negative inotropy in streptozotocin-treated mice. These results suggest that the reduced α-adrenoceptor-mediated inotropy in the diabetic mouse myocardium is partly due to its prolonged action potential. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  2. Minimal string theory is logarithmic

    International Nuclear Information System (INIS)

    Ishimoto, Yukitaka; Yamaguchi, Shun-ichi

    2005-01-01

    We study the simplest examples of minimal string theory whose worldsheet description is the unitary (p,q) minimal model coupled to two-dimensional gravity ( Liouville field theory). In the Liouville sector, we show that four-point correlation functions of 'tachyons' exhibit logarithmic singularities, and that the theory turns out to be logarithmic. The relation with Zamolodchikov's logarithmic degenerate fields is also discussed. Our result holds for generic values of (p,q)

  3. Annual Waste Minimization Summary Report

    International Nuclear Information System (INIS)

    Haworth, D.M.

    2011-01-01

    This report summarizes the waste minimization efforts undertaken by National Security TechnoIogies, LLC, for the U. S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), during calendar year 2010. The NNSA/NSO Pollution Prevention Program establishes a process to reduce the volume and toxicity of waste generated by NNSA/NSO activities and ensures that proposed methods of treatment, storage, and/or disposal of waste minimize potential threats to human health and the environment.

  4. Effect of amiodarone on the conversion of thyroxine to triiodotironine in rat myocardium in vivo and in vitro

    International Nuclear Information System (INIS)

    Ceppi, J.A.; Gonzalez, M.R.; Zaninovich, A.A.

    1988-01-01

    It was studied the effect of the antiarrhythmic drug amiodarone, on the conversion of T 4 to T 3 by rat myocardium and liver. Wistar rats were injected with amiodarone (AM) or iopanoic acid (IOP), afterwards the liver and the heart were homogenized in krebs-ringer phosphate. Aliquots of 400μl of the homogenized were separated and DTT 8mM and 10 -2 μCi 125 I-T 4 or 125 I-T 3 were added (either the conversion of T 4 to T 3 or degradation of T 3 are measured). In vitro: were added AM 0,1 mM or IOP 10mM. Incubation proceeded for 2 hours at 37 deg C and aliquots were chromatographied. The conversion of T 4 to T 3 in the myocardium and liver in vivo decreased, but in vitro did not have any deiodination of T 4 and the IOP reduced the production of T 3 by heart. Neither drug altered the deiodination of T 3 by heart or liver homogenates. Serum TSH and T 3 were decreased by AM and serum T 4 increased. IOP caused similar variations in T 4 and T 3 , but serum TSH was increased. It is concluded that blocking the T 3 miocardial production by AM may not be the cause of the antiarrhythmic effect of the drug. (M.E.L.) [es

  5. Increased cross-bridge recruitment contributes to transient increase in force generation beyond maximal capacity in human myocardium.

    Science.gov (United States)

    Milani-Nejad, Nima; Chung, Jae-Hoon; Canan, Benjamin D; Fedorov, Vadim V; Whitson, Bryan A; Kilic, Ahmet; Mohler, Peter J; Janssen, Paul M L

    2018-01-01

    Cross-bridge attachment allows force generation to occur, and rate of tension redevelopment (k tr ) is a commonly used index of cross-bridge cycling rate. Tension overshoots have been observed briefly after a slack-restretch k tr maneuver in various species of animal models and humans. In this study, we set out to determine the properties of these overshoots and their possible underlying mechanism. Utilizing human cardiac trabeculae, we have found that tension overshoots are temperature-dependent and that they do not occur at resting states. In addition, we have found that myosin cross-bridge cycle is vital to these overshoots as inhibition of the cycle results in the blunting of the overshoots and the magnitude of the overshoots are dependent on the level of myofilament activation. Lastly, we show that the number of cross-bridges transiently increase during tension overshoots. These findings lead us to conclude that tension overshoots are likely due to a transient enhancement of the recruitment of myosin heads into the cross-bridge cycling, regulated by the myocardium, and with potential physiological significance in determining cardiac output. We show that isolated human myocardium is capable of transiently increasing its maximal force generation capability by increasing cross-bridge recruitment following slack-restretch maneuver. This process can potentially have important implications and significance in cardiac contraction in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. The effect of rigor mortis on the passage of erythrocytes and fluid through the myocardium of isolated dog hearts.

    Science.gov (United States)

    Nevalainen, T J; Gavin, J B; Seelye, R N; Whitehouse, S; Donnell, M

    1978-07-01

    The effect of normal and artificially induced rigor mortis on the vascular passage of erythrocytes and fluid through isolated dog hearts was studied. Increased rigidity of 6-mm thick transmural sections through the centre of the posterior papillary muscle was used as an indication of rigor. The perfusibility of the myocardium was tested by injecting 10 ml of 1% sodium fluorescein in Hanks solution into the circumflex branch of the left coronary artery. In prerigor hearts (20 minute incubation) fluorescein perfused the myocardium evenly whether or not it was preceded by an injection of 10 ml of heparinized dog blood. Rigor mortis developed in all hearts after 90 minutes incubation or within 20 minutes of perfusing the heart with 50 ml of 5 mM iodoacetate in Hanks solution. Fluorescein injected into hearts in rigor did not enter the posterior papillary muscle and adjacent subendocardium whether or not it was preceded by heparinized blood. Thus the vascular occlusion caused by rigor in the dog heart appears to be so effective that it prevents flow into the subendocardium of small soluble ions such as fluorescein.

  7. Peculiarities of cardiac hemodynamics and functional state of left ventricular myocardium in teenagers with connective heart tissue dysplasia

    Directory of Open Access Journals (Sweden)

    Makhmudova F.M.

    2011-03-01

    Full Text Available The aim of investigation is to study heart hemodynamics in teenagers with connective tissue dysplasia of heart (CTDH. 35 patients ages 12 to 15 years with CTDH have been observed: Group I (n=14 are the patients with mitral valve prolapse (MVP without mitral regurgitation (MR and myxomatous degeneration(MD or isolated minor heart abnormalities (MHA, Group II (n=11are patients with MVP and MR in combination with 1 or2 MHA, and Group III (n=10 are patients with MVP and mixoid degeneration (MD in combination with 2 or more MHA. The control group consisted of 15 patients of the same age without MHA. All the children passed Doppler and echocardiography. According to the results significant changes of cardiohemodynamic indices in patients of Group I were not observed. The changes of size and volume indices of the left ventricle (LV, increase in wall thickness and diastolic dysfunction of the LV were observed in Group II. The significant changes of systolic function of left ventricular myocardium were observed in Group III. The study comes to the conclusion that teenagers with CTDH have definite changes of heart hemodynamics and functional state of left ventricular myocardium. These changes depend on mitral regurgitation, myxomatous degeneration and MHA combination

  8. Deterministic Encapsulation of Human Cardiac Stem Cells in Variable Composition Nanoporous Gel Cocoons To Enhance Therapeutic Repair of Injured Myocardium.

    Science.gov (United States)

    Kanda, Pushpinder; Alarcon, Emilio I; Yeuchyk, Tanya; Parent, Sandrine; de Kemp, Robert A; Variola, Fabio; Courtman, David; Stewart, Duncan J; Davis, Darryl R

    2018-04-20

    Although cocooning explant-derived cardiac stem cells (EDCs) in protective nanoporous gels (NPGs) prior to intramyocardial injection boosts long-term cell retention, the number of EDCs that finally engraft is trivial and unlikely to account for salutary effects on myocardial function and scar size. As such, we investigated the effect of varying the NPG content within capsules to alter the physical properties of cocoons without influencing cocoon dimensions. Increasing NPG concentration enhanced cell migration and viability while improving cell-mediated repair of injured myocardium. Given that the latter occurred with NPG content having no detectable effect on the long-term engraftment of transplanted cells, we found that changing the physical properties of cocoons prompted explant-derived cardiac stem cells to produce greater amounts of cytokines, nanovesicles, and microRNAs that boosted the generation of new blood vessels and new cardiomyocytes. Thus, by altering the physical properties of cocoons by varying NPG content, the paracrine signature of encapsulated cells can be enhanced to promote greater endogenous repair of injured myocardium.

  9. Effects of Using Tricaine Methanesulfonate and Metomidate before Euthanasia on the Contractile Properties of Rainbow Trout (Oncorhynchus mykiss) Myocardium.

    Science.gov (United States)

    Roberts, Jordan C; Syme, Douglas A

    2016-01-01

    Because many anesthetics work through depressing cell excitability, unanesthetized euthanasia has become common for research involving excitable tissues (for example muscle and nerve) to avoid these depressive effects. However, anesthetic use during euthanasia may be indicated for studies involving isolated tissues if the potential depressive effects of brief anesthetic exposure dissipate after subsequent tissue isolation, washout, and saline perfusion. We explore this here by measuring whether, when applied prior to euthanasia, standard immersion doses of 2 fish anesthetics, tricaine methanesulfonate (TMS; 100 mg/L, n = 6) and methyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylate (metomidate, 10 mg/L, n = 6), have residual effects on the contractile properties (force and work output) of isolated and saline-perfused ventricular compact myocardium from rainbow trout (Oncorhynchus mykiss). Results suggest that direct exposure of muscle to immersion doses of TMS-but not metomidate-impairs muscle contractile performance. However, brief exposure (2 to 3 min) to either anesthetic during euthanasia only-providing that the agent is washed out prior to tissue experimentation-does not have an effect on the contractile properties of the myocardium. Therefore, the use of TMS, metomidate, and perhaps other anesthetics that depress cell excitability during euthanasia may be indicated when conducting research on isolated and rinsed tissues.

  10. Cardiac lymphoscintigraphy following closed-chest catheter injection of radiolabeled colloid into the myocardium of dogs: concise communication

    International Nuclear Information System (INIS)

    Osbakken, M.D.; Kopiwoda, S.Y.; Swan, A.; Castronovo, F.P.; Strauss, H.W.

    1982-01-01

    A catheter technique for injection of radiolabeled colloids into the myocardium was developed and tested in a series of 15 dogs. A multipurpose angiographic catheter was modified to permit an inner core of PE-50 polyethylene tubing, tipped with a 23-gage needle, to pass through the lumen for intra-myocardial injection of radiocolloids. For injection of the left ventricle, the catheter is introduced through the femoral artery: for the right ventricle, the femoral vein. The catheter advanced under fluoroscopy until the desired surface for injection is reached. The inner core is then extended to lodge the needle in the endocardium. A mixture of Renografin (to confirm the endocardial injection site) and radiolabeled colloid was injected in 13 animals. Ten minutes after injection, scintigraphy was begun and continued for up to 6 hr. In three dogs the procedure was repeated 3 or 4 times. From two to five nodes were visible in all animals, irrespective of whether the right or left ventricular myocardium was injected. In two animals the injection was given intravenously, and no nodes were seen. These data suggest that cardiac lymphatic drainage can be studied with a catheter injection method

  11. Cardiac lymphoscintigraphy following closed-chest catheter injection of radiolabeled colloid into the myocardium of dogs: concise communication

    International Nuclear Information System (INIS)

    Osbakken, M.D.; Kopiwoda, S.Y.; Swan, A.; Castronovo, F.P.; Strauss, H.W.

    1982-01-01

    A catheter technique for injection of radiolabeled colloids into the myocardium was developed and tested in a series of 15 dogs. A multipurpose angiographic catheter was modified to permit an inner core of PE-50 polyethylene tubing, tipped with a 23-gage needle, to pass through the lumen for intra-myocardial injection of the femoral artery: for the right ventricle, the femoral vein. The catheter advanced under fluoroscopy until the desired surface for injection is reached. The inner core is then extended to lodge the needle in the endocardium. A mixture of Renogratin (to confirm the endocardial injection site) and radiolabeled colloid was injected in up to 6 hr. In three dogs the procedure was repeated 3 or 4 times. From two to five nodes were visible in all animals, irrespective of whether the right or left ventricular myocardium was injected. In two animals the injection was given intravenously, and no nodes were seen. These data suggest that cardiac lymphatic drainage can be studied with a catheter injection method

  12. A coupled 3D-1D numerical monodomain solver for cardiac electrical activation in the myocardium with detailed Purkinje network

    Science.gov (United States)

    Vergara, Christian; Lange, Matthias; Palamara, Simone; Lassila, Toni; Frangi, Alejandro F.; Quarteroni, Alfio

    2016-03-01

    We present a model for the electrophysiology in the heart to handle the electrical propagation through the Purkinje system and in the myocardium, with two-way coupling at the Purkinje-muscle junctions. In both the subproblems the monodomain model is considered, whereas at the junctions a resistor element is included that induces an orthodromic propagation delay from the Purkinje network towards the heart muscle. We prove a sufficient condition for convergence of a fixed-point iterative algorithm to the numerical solution of the coupled problem. Numerical comparison of activation patterns is made with two different combinations of models for the coupled Purkinje network/myocardium system, the eikonal/eikonal and the monodomain/monodomain models. Test cases are investigated for both physiological and pathological activation of a model left ventricle. Finally, we prove the reliability of the monodomain/monodomain coupling on a realistic scenario. Our results underlie the importance of using physiologically realistic Purkinje-trees with propagation solved using the monodomain model for simulating cardiac activation.

  13. Lebetin 2, a Snake Venom-Derived Natriuretic Peptide, Attenuates Acute Myocardial Ischemic Injury through the Modulation of Mitochondrial Permeability Transition Pore at the Time of Reperfusion.

    Directory of Open Access Journals (Sweden)

    Bochra Tourki

    Full Text Available Cardiac ischemia is one of the leading causes of death worldwide. It is now well established that natriuretic peptides can attenuate the development of irreversible ischemic injury during myocardial infarction. Lebetin 2 (L2 is a new discovered peptide isolated from Macrovipera lebetina venom with structural similarity to B-type natriuretic peptide (BNP. Our objectives were to define the acute cardioprotective actions of L2 in isolated Langendorff-perfused rat hearts after regional or global ischemia-reperfusion (IR. We studied infarct size, left ventricular contractile recovery, survival protein kinases and mitochondrial permeability transition pore (mPTP opening in injured myocardium. L2 dosage was determined by preliminary experiments at its ability to induce cyclic guanosine monophosphate (cGMP release without changing hemodynamic effects in normoxic hearts. L2 was found to be as effective as BNP in reducing infarct size after the induction of either regional or global IR. Both peptides equally improved contractile recovery after regional IR, but only L2 increased coronary flow and reduced severe contractile dysfunction after global ischemia. Cardioprotection afforded by L2 was abolished after isatin or 5-hydroxydecanote pretreatment suggesting the involvement of natriuretic peptide receptors and mitochondrial KATP (mitoKATP channels in the L2-induced effects. L2 also increased survival protein expression in the reperfused myocardium as evidenced by phosphorylation of signaling pathways PKCε/ERK/GSK3β and PI3K/Akt/eNOS. IR induced mitochondrial pore opening, but this effect was markedly prevented by L2 treatment. These data show that L2 has strong cardioprotective effect in acute ischemia through stimulation of natriuretic peptide receptors. These beneficial effects are mediated, at least in part, by mitoKATP channel opening and downstream activated survival kinases, thus delaying mPTP opening and improving IR-induced mitochondrial

  14. Prothrombin and risk of venous thromboembolism, ischemic heart disease and ischemic cerebrovascular disease in the general population

    DEFF Research Database (Denmark)

    Weischer, Maren; Juul, Klaus; Zacho, Jeppe

    2010-01-01

    OBJECTIVE: We tested the hypotheses that Prothrombin G20210A heterozygosity associate with increased risk of venous thromboembolism (VTE), ischemic heart disease (IHD), and ischemic cerebrovascular disease (ICVD) in the general population and re-tested risk of IHD and ICVD in two case......-control studies. METHODS: 9231 individuals from the Danish general population were followed for VTE (VTE=DVT+PE), deep venous thrombosis (DVT), pulmonary embolism (PE), IHD, myocardial infarction (MI), ICVD, and ischemic stroke (IS) for a median of 24 years. Case-control studies included 2461 IHD cases and 867...

  15. Effect of acidity and chemical composition of sup(99m)Tc-radiopharmaceuticals on sup(99m)Tc accumulation in necrotic tissue of rat myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Vilcek, S; Machan, V; Kalincak, M [Ustav Radioekologie a Vyuzitia Jadrovej Techniky, Kosice (Czechoslovakia); Nicak, A [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Lekarska Fakulta

    1981-04-30

    Experiments showed that the cumulation of technetium-99m following the administration of /sup 99m/Tc-Sn-pyrophosphate and s/sup 99m/Tc-Sn-oxytetracycline in the necrotic tissue of rat myocardium damaged by cauterization depended on the end pH value. The maximum /sup 99m/Tc cumulation in the myocardial lesion was noted when the end pH value ranged in 5.5 to 6.0. It appeared that pyrophosphate concentration decrease below the critical limit not only affected the cumulation of /sup 99m/Tc in the particular organs but also in the necrotic tissue of the myocardium.

  16. Effect of acidity and chemical composition of sup(99m)Tc-radiopharmaceuticals on sup(99m)Tc accumulation in necrotic tissue of rat myocardium

    International Nuclear Information System (INIS)

    Vilcek, S.; Machan, V.; Kalincak, M.; Nicak, A.

    1981-01-01

    Experiments showed that the cumulation of technetium-99m following the administration of sup(99m)Tc-Sn-pyrophosphate and sup(99m)Tc-Sn-oxytetracycline in the necrotic tissue of rat myocardium damaged by cauterization depended on the end pH value. The maximum sup(99m)Tc cumulation in the myocardial lesion was noted when the end pH value ranged in 5.5 to 6.0. It appeared that pyrophosphate concentration decrease below the critical limit not only affected the cumulation of sup(99m)Tc in the particular organs but also in the necrotic tissue of the myocardium. (author)

  17. Safety and Time Course of Drip-and-Ship in Treatment of Acute Ischemic Stroke.

    Science.gov (United States)

    Ishihara, Hideyuki; Oka, Fumiaki; Oku, Takayuki; Shinoyama, Mizuya; Suehiro, Eiichi; Sugimoto, Kazutaka; Suzuki, Michiyasu

    2017-11-01

    The drip-and-ship approach allows intravenous tissue plasminogen activator therapy and adjuvant endovascular treatment in acute ischemic stroke, even in rural areas. Here, we examined the safety and time course of the drip-and-ship approach. Fifty consecutive cases treated with the drip-and-ship approach (drip-and-ship group) in June 2009 to March 2016 were retrospectively examined. Changes in mean blood pressure, systemic complications, and neurological complications were compared according to method of transportation. Time courses were compared between drip-and-ship and direct admission groups during the same period. In the drip-and-ship group, 33 and 17 patients were transferred to hospital by ambulance and helicopter, respectively. One patient suffered hemorrhagic infarction during transportation by ambulance. Mean blood pressure change was lower in patients transferred by helicopter than ambulance (<5 mmHg versus 12.2 mmHg, respectively). The mean onset-to-door times in the drip-and-ship and direct admission groups were 71 and 64 minutes, respectively, and mean door-to-needle times were 70 and 47 minutes, respectively (P =.002). Although mean transportation time from the primary stroke hospital to our hospital was 32 minutes, the entry-to-exit time from the primary stroke hospital was 113 minutes. Thereafter, there was an average delay of 100 minutes until reperfusion compared with the direct admission group. Drip-and-ship was relatively safe in this small series. Transportation by helicopter was less stressful for acute ischemic stroke patients. It is important to reduce door-to-needle time and needle-to-departure time in the primary stroke hospital to minimize the time until treatment in cases of acute ischemic stroke. Copyright © 2017. Published by Elsevier Inc.

  18. Head movement during CT brain perfusion acquisition of patients with suspected acute ischemic stroke

    International Nuclear Information System (INIS)

    Fahmi, F.; Beenen, L.F.M.; Streekstra, G.J.; Janssen, N.Y.; Jong, H.W. de; Riordan, A.; Roos, Y.B.; Majoie, C.B.; Bavel, E. van; Marquering, H.A.

    2013-01-01

    Objective: Computed Tomography Perfusion (CTP) is a promising tool to support treatment decision for acute ischemic stroke patients. However, head movement during acquisition may limit its applicability. Information of the extent of head motion is currently lacking. Our purpose is to qualitatively and quantitatively assess the extent of head movement during acquisition. Methods: From 103 consecutive patients admitted with suspicion of acute ischemic stroke, head movement in 220 CTP datasets was qualitatively categorized by experts as none, minimal, moderate, or severe. The movement was quantified using 3D registration of CTP volume data with non-contrast CT of the same patient; yielding 6 movement parameters for each time frame. The movement categorization was correlated with National Institutes of Health Stroke Scale (NIHSS) score and baseline characteristic using multinomial logistic regression and student's t-test respectively. Results: Moderate and severe head movement occurred in almost 25% (25/103) of all patients with acute ischemic stroke. The registration technique quantified head movement with mean rotation angle up to 3.6° and 14°, and mean translation up to 9.1 mm and 22.6 mm for datasets classified as moderate and severe respectively. The rotation was predominantly in the axial plane (yaw) and the main translation was in the scan direction. There was no statistically significant association between movement classification and NIHSS score and baseline characteristics. Conclusions: Moderate or severe head movement during CTP acquisition of acute stroke patients is quite common. The presented registration technique can be used to automatically quantify the movement during acquisition, which can assist identification of CTP datasets with excessive head movement

  19. Head movement during CT brain perfusion acquisition of patients with suspected acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Fahmi, F., E-mail: f.fahmi@amc.uva.nl [Department of Biomedical Engineering and Physics, AMC, Amsterdam (Netherlands); Beenen, L.F.M., E-mail: l.f.beenen@amc.uva.nl [Department of Radiology, AMC, Amsterdam (Netherlands); Streekstra, G.J., E-mail: g.j.streekstra@amc.uva.nl [Department of Biomedical Engineering and Physics, AMC, Amsterdam (Netherlands); Janssen, N.Y., E-mail: n.n.janssen@amc.uva.nl [Department of Biomedical Engineering and Physics, AMC, Amsterdam (Netherlands); Jong, H.W. de, E-mail: H.W.A.M.deJong@umcutrecht.nl [Department of Radiology, UMC Utrecht, 3584CX, Utrecht (Netherlands); Riordan, A., E-mail: alan.riordan@gmail.com [Department of Radiology, UMC Utrecht, 3584CX, Utrecht (Netherlands); Roos, Y.B., E-mail: y.b.roos@amc.uva.nl [Department of Neurology, AMC, Amsterdam (Netherlands); Majoie, C.B., E-mail: c.b.majoie@amc.uva.nl [Department of Radiology, AMC, Amsterdam (Netherlands); Bavel, E. van, E-mail: e.vanbavel@amc.uva.nl [Department of Biomedical Engineering and Physics, AMC, Amsterdam (Netherlands); Marquering, H.A., E-mail: h.a.marquering@amc.uva.nl [Department of Biomedical Engineering and Physics, AMC, Amsterdam (Netherlands); Department of Radiology, AMC, Amsterdam (Netherlands)

    2013-12-01

    Objective: Computed Tomography Perfusion (CTP) is a promising tool to support treatment decision for acute ischemic stroke patients. However, head movement during acquisition may limit its applicability. Information of the extent of head motion is currently lacking. Our purpose is to qualitatively and quantitatively assess the extent of head movement during acquisition. Methods: From 103 consecutive patients admitted with suspicion of acute ischemic stroke, head movement in 220 CTP datasets was qualitatively categorized by experts as none, minimal, moderate, or severe. The movement was quantified using 3D registration of CTP volume data with non-contrast CT of the same patient; yielding 6 movement parameters for each time frame. The movement categorization was correlated with National Institutes of Health Stroke Scale (NIHSS) score and baseline characteristic using multinomial logistic regression and student's t-test respectively. Results: Moderate and severe head movement occurred in almost 25% (25/103) of all patients with acute ischemic stroke. The registration technique quantified head movement with mean rotation angle up to 3.6° and 14°, and mean translation up to 9.1 mm and 22.6 mm for datasets classified as moderate and severe respectively. The rotation was predominantly in the axial plane (yaw) and the main translation was in the scan direction. There was no statistically significant association between movement classification and NIHSS score and baseline characteristics. Conclusions: Moderate or severe head movement during CTP acquisition of acute stroke patients is quite common. The presented registration technique can be used to automatically quantify the movement during acquisition, which can assist identification of CTP datasets with excessive head movement.

  20. Safety and feasibility of post-stroke care and exercise after minor ischemic stroke or transient ischemic attack: MotiveS & MoveIT

    NARCIS (Netherlands)

    Boss, H.M.; Van Schaik, S.M.; Deijle, I.A.; de Melker, E.C.; van den Berg, B.M.; Scherder, E.J.A.; Bosboom, W.M.J.; Weinstein, H.C.; van den Berg-Vos, R.M.

    2014-01-01

    Background: Despite the beneficial effect of cardiac rehabilitation after myocardial infarction, a rehabilitation program to improve cardiorespiratory fitness and influence secondary prevention has not been implemented for ischemic stroke and transient ischemic attack (TIA). Objective: To