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Sample records for myocardial alterations due

  1. Myocardial failure with altered response to adrenaline in endotoxin shock

    PubMed Central

    Archer, L.T.; Black, M.R.; Hinshaw, L.B.

    1975-01-01

    1 There is a growing concensus that myocardial performance in the early stages of experimental endotoxic and septic shock is relatively normal; however, recent reports have identified an intermediate phase of shock when myocardial dysfunction is clearly apparent. 2 The mechanism of dysfunction has become a subject of intense investigation. A current view is that altered myocardial responsiveness to circulating catecholamines may play an important role in the dysfunction observed after endotoxin administration. The present studies, in which an isolated working heart preparation of the dog was used, were designed to test this hypothesis. This particular experimental preparation was selected to provide an adequate interpretation of results; cardiac output, afterload, and concentrations of adrenaline reaching the coronary vascular bed were controlled in all experiments. Responses to infusions of adrenaline were recorded in the `steady-state' condition. Control (non-shocked) heart responses to adrenaline were highly reproducible in terms of inotropic, chronotropic and coronary vascular behaviour. 3 Results from the study document myocardial dysfunction within 4-6 h following an LD70 endotoxin administration on the basis of increased left ventricular end diastolic pressure (LVEDP), decreased cardiac power and myocardial efficiency, and depressed negative and positive dP/dt parameters. 4 Findings suggest significantly altered responsiveness of the myocardium to infused adrenaline at rates of 1, 2, and 5 μg/min with concentrations between 10 and 1 ng/ml blood. LVEDP was elevated while calculated power and efficiency parameters remained significantly below control values during infusion of adrenaline in endotoxin-treated hearts. Depressions of responsiveness were interpreted to occur on the basis of failure to restore positive and negative dP/dt to normal values and depressed coronary blood flow responses during adrenaline administration. Increases in coronary flow were

  2. Cardiovascular collapse after myocardial infarction due to centipede bite.

    PubMed

    Üreyen, Çağin Mustafa; Arslan, Şakir; Baş, Cem Yunus

    2015-07-01

    Centipede bites have been reported to cause localized and/or systemic symptoms including local pain, erythema and edema, nausea and vomiting, palpitations, headache, lymphadenopathy, and rhabdomyolysis. However, acute myocardial infarction due to centipede envenomation is reported in only three cases in English medical literature.We present a case of 31-year-old male bitten by a golden colored centipede leading to myocardial infarction and cardiopulmonary arrest which is seen very rarely. The patient was admitted to emergency department with a swollen and painful right foot. However, typical chest pain became the major complaint and cardiopulmonary arrest developed while electrocardiography was being obtained. The patient was resuscitated successfully for 5 min and acute infero-posterolateral myocardial infarction was detected on electrocardiography. PMID:25994876

  3. Acute myocardial infarction due to blunt chest trauma.

    PubMed

    Sinha, Ajay Kumar; Agrawal, R K; Singh, Arun; Kumar, Rajiv; Kumar, Sanjeev; Sinha, Ajay; Saurabh; Kumar, Amit

    2002-01-01

    We report a case of blunt chest injury following a road accident leading to damage of the left main and left anterior descending coronary arteries causing acute myocardial infarction in a young person. PMID:12674188

  4. Myocardial Perfusion and Function Are Distinctly Altered by Sevoflurane Anesthesia in Diet-Induced Prediabetic Rats

    PubMed Central

    van den Brom, Charissa E.; Boly, Chantal A.; Bulte, Carolien S. E.; van den Akker, Rob F. P.; Kwekkeboom, Rick F. J.; Loer, Stephan A.; Boer, Christa; Bouwman, R. Arthur

    2016-01-01

    Preservation of myocardial perfusion during surgery is particularly important in patients with increased risk for perioperative complications, such as diabetes. Volatile anesthetics, like sevoflurane, have cardiodepressive effects and may aggravate cardiovascular complications. We investigated the effect of sevoflurane on myocardial perfusion and function in prediabetic rats. Rats were fed a western diet (WD; n = 18) or control diet (CD; n = 18) for 8 weeks and underwent (contrast) echocardiography to determine perfusion and function during baseline and sevoflurane exposure. Myocardial perfusion was estimated based on the product of microvascular filling velocity and blood volume. WD-feeding resulted in a prediabetic phenotype characterized by obesity, hyperinsulinemia, hyperlipidemia, glucose intolerance, and hyperglycemia. At baseline, WD-feeding impaired myocardial perfusion and systolic function compared to CD-feeding. Exposure of healthy rats to sevoflurane increased the microvascular filling velocity without altering myocardial perfusion but impaired systolic function. In prediabetic rats, sevoflurane did also not affect myocardial perfusion; however, it further impaired systolic function. Diet-induced prediabetes is associated with impaired myocardial perfusion and function in rats. While sevoflurane further impaired systolic function, it did not affect myocardial perfusion in prediabetic rats. Our findings suggest that sevoflurane anesthesia leads to uncoupling of myocardial perfusion and function, irrespective of the metabolic state. PMID:26824042

  5. Myocardial Perfusion and Function Are Distinctly Altered by Sevoflurane Anesthesia in Diet-Induced Prediabetic Rats.

    PubMed

    van den Brom, Charissa E; Boly, Chantal A; Bulte, Carolien S E; van den Akker, Rob F P; Kwekkeboom, Rick F J; Loer, Stephan A; Boer, Christa; Bouwman, R Arthur

    2016-01-01

    Preservation of myocardial perfusion during surgery is particularly important in patients with increased risk for perioperative complications, such as diabetes. Volatile anesthetics, like sevoflurane, have cardiodepressive effects and may aggravate cardiovascular complications. We investigated the effect of sevoflurane on myocardial perfusion and function in prediabetic rats. Rats were fed a western diet (WD; n = 18) or control diet (CD; n = 18) for 8 weeks and underwent (contrast) echocardiography to determine perfusion and function during baseline and sevoflurane exposure. Myocardial perfusion was estimated based on the product of microvascular filling velocity and blood volume. WD-feeding resulted in a prediabetic phenotype characterized by obesity, hyperinsulinemia, hyperlipidemia, glucose intolerance, and hyperglycemia. At baseline, WD-feeding impaired myocardial perfusion and systolic function compared to CD-feeding. Exposure of healthy rats to sevoflurane increased the microvascular filling velocity without altering myocardial perfusion but impaired systolic function. In prediabetic rats, sevoflurane did also not affect myocardial perfusion; however, it further impaired systolic function. Diet-induced prediabetes is associated with impaired myocardial perfusion and function in rats. While sevoflurane further impaired systolic function, it did not affect myocardial perfusion in prediabetic rats. Our findings suggest that sevoflurane anesthesia leads to uncoupling of myocardial perfusion and function, irrespective of the metabolic state. PMID:26824042

  6. Nitrendipine binding in congestive heart failure due to myocardial infarction

    SciTech Connect

    Dixon, I.M.; Lee, S.L.; Dhalla, N.S. )

    1990-03-01

    Depressed cardiac pump function is the hallmark of congestive heart failure, and it is suspected that decreased influx of Ca2+ into the cardiac cell is responsible for depressed contractile function. Since Ca2+ channels in the sarcolemmal membrane are considered to be an important route for the entry of Ca2+, we examined the status of Ca2+ receptors/channels in failing rat hearts after myocardial infarction of the left ventricular free wall. For this purpose, the left coronary artery was ligated and hearts were examined 4, 8, and 16 weeks later; sham-operated animals served as controls. Hemodynamic assessment revealed decreased total mechanical energy (left ventricular systolic pressure x heart rate), increased left ventricular diastolic pressure, and decreased positive and negative dP/dt in experimental animals at 4, 8, and 16 weeks. Although accumulation of ascites in the abdominal cavity was evident at 4 weeks, other clinical signs of congestive heart failure in experimental rats were evident from the presence of lung congestion and cardiac dilatation at 8 and 16 weeks after induction of myocardial infarction. The density of Ca2+ receptors/channels in crude membranes, as assessed by (3H)nitrendipine binding assay, was found to be decreased in the uninfarcted experimental left ventricle at 8 and 16 weeks; however, no change in the affinity of nitrendipine was evident. A similar depression in the specific binding of another dihydropyridine compound, (3H)PN200-110, was also evident in failing hearts. Brain and skeletal muscle crude membrane preparations, unlike those of the right ventricle and liver, revealed a decrease in Ca2+ receptors/channels density in experimental animals at 16 weeks.

  7. Acute myocardial infarction due to left main compression aortic dissection treated by direct stenting.

    PubMed

    Cardozo, Carlos; Riadh, Rihani; Mazen, Moukahal

    2004-02-01

    We describe a case of acute myocardial infarction (AMI) due to compression of the left main coronary artery (LMCA) by a false channel created by an acute aortic dissection (AAD). The dynamic pattern of artery obstruction is detailed as a key element to the diagnosis of extrinsic coronary compression throughout the angiography. Treatment by direct stenting restored complete anterograde coronary flow and improved myocardial perfusion. PMID:14760201

  8. Altered phosphate metabolism in myocardial infarction: P-31 MR spectroscopy

    SciTech Connect

    Bottomley, P.A.; Herfkens, R.J.; Smith, L.S.; Bashore, T.M.

    1987-12-01

    The high-energy myocardial phosphate metabolism of four patients with acute anterior myocardial infarction after coronary angioplasty and drug therapy was evaluated with cardiac-gated phosphorus magnetic resonance (MR) depth-resolved surface coil spectroscopy (DRESS) 5-9 days after the onset of symptoms. Significant reductions (about threefold) in the phosphocreatine (PCr) to inorganic phosphate (Pi) ratio and elevations in the Pi to adenosine triphosphate (ATP) ratio were observed in endocardially or transmurally derived MR spectra when compared with values from epicardially displaced spectra and values from seven healthy volunteers (P less than .05). High-energy phosphate metabolites and Pi ratios did not vary significantly during the cardiac cycle in healthy volunteers. However, contamination of Pi resonances by phosphomonoester components, including blood 2,3-diphosphoglycerate, precluded accurate spectral quantification of Pi and pH. The results indicate that localized P-31 MR spectroscopy may be used to directly assess cellular energy reserve in clinical myocardial infarction and to evaluate metabolic response to interventions.

  9. Altered filtrability of white blood cells after myocardial infarction.

    PubMed

    Bogár, L; Mikita, J; Nash, G B; Smith, M J; Dormandy, J A; Tekeres, M

    1989-01-01

    Abnormal white blood cell rheological behaviour has been implicated as a cause of blood flow disturbances under conditions of ischaemia and reduced perfusion pressure. Accordingly, we have tested the mechanical properties of white cells following myocardial infarction by measuring the rate at which suspension of these cells cause plugging of Nuclepore filters. The number of clogging particles in a standard white cell suspension increased by the third day after infarction but subsequently decreased to the control levels. Since white cells can cause blockage of narrow blood vessels, it is assumed that such changes in cellular properties may influence the eventual extent of infarction. PMID:2812961

  10. Altered Gene Expression Pattern in Peripheral Blood Mononuclear Cells in Patients with Acute Myocardial Infarction

    PubMed Central

    Kiliszek, Marek; Burzynska, Beata; Michalak, Marcin; Gora, Monika; Winkler, Aleksandra; Maciejak, Agata; Leszczynska, Agata; Gajda, Ewa; Kochanowski, Janusz; Opolski, Grzegorz

    2012-01-01

    Background Despite a substantial progress in diagnosis and therapy, acute myocardial infarction (MI) is a major cause of mortality in the general population. A novel insight into the pathophysiology of myocardial infarction obtained by studying gene expression should help to discover novel biomarkers of MI and to suggest novel strategies of therapy. The aim of our study was to establish gene expression patterns in leukocytes from acute myocardial infarction patients. Methods and Results Twenty-eight patients with ST-segment elevation myocardial infarction (STEMI) were included. The blood was collected on the 1st day of myocardial infarction, after 4–6 days, and after 6 months. Control group comprised 14 patients with stable coronary artery disease, without history of myocardial infarction. Gene expression analysis was performed with Affymetrix Human Gene 1.0 ST microarrays and GCS3000 TG system. Lists of genes showing altered expression levels (fold change >1.5, p<0.05) were submitted to Ingenuity Pathway Analysis. Gene lists from each group were examined for canonical pathways and molecular and cellular functions. Comparing acute phase of MI with the same patients after 6 months (stable phase) and with control group we found 24 genes with changed expression. In canonical analysis three pathways were highlighted: signaling of PPAR (peroxisome proliferator-activated receptor), IL-10 and IL-6 (interleukin 10 and 6). Conclusions In the acute phase of STEMI, dozens of genes from several pathways linked with lipid/glucose metabolism, platelet function and atherosclerotic plaque stability show altered expression. Up-regulation of SOCS3 and FAM20 genes in the first days of myocardial infarction is observed in the vast majority of patients. PMID:23185530

  11. Adenylyl cyclase regulation in heart failure due to myocardial infarction in rats.

    PubMed

    Bräunig, Jörg H; Albrecht-Küpper, Barbara; Seifert, Roland

    2014-04-01

    Cardiac adenylyl cyclase (AC) activity was described to be differentially regulated in left and right ventricles (LVs and RVs) of rats with heart failure (HF) due to LV myocardial infarction (MI) (Sethi et al. Am J Physiol 272:H884-H893, 1997). AC activities in LVs and RVs were increased and decreased respectively in rats 8 and 16 weeks post MI under basal and stimulatory conditions including AC activation via β-adrenergic receptors (β-ARs), stimulatory G protein (Gs), and direct AC activation with forskolin (FS). The current study aimed to detect alterations in rat heart AC activities in a comparable model of HF 9 weeks post LV MI. Therefore, cardiac AC activities were measured under basal and β-AR-, Gs-, or FS-stimulated conditions as well as under inhibition with various MANT [2'(3')-O-(N-methylanthraniloyl)]-nucleotide AC inhibitors and the P-site AC inhibitors NKY80 [2-amino-7-(2-furanyl)-7,8-dihydro-5(6H)-quinazolinone] and vidarabine (9-β-D-arabinosyladenine, AraAde). Basal and stimulated AC activities along with AC inhibition experiments did not reveal evidence for changes in AC activity in LVs and RVs from MI group animals despite the presence of congestive HF. However, our study is indeterminate. Further studies are required to identify the factors responsible for previously described changes in cardiac AC activity in MI induced HF and to elucidate the role of altered AC regulation in the pathophysiology of HF. In order to detect small changes in AC regulation, larger group sizes than the ones used in our present study are required. PMID:24276219

  12. Case of angina pectoris at rest and during effort due to coronary spasm and myocardial bridging

    PubMed Central

    Teragawa, Hiroki; Fujii, Yuichi; Ueda, Tomohiro; Murata, Daiki; Nomura, Shuichi

    2015-01-01

    We present a case of a 71-year-old male who had chest symptoms at rest and during effort. He had felt chest oppression during effort for 1 year, and his chest symptoms had recently worsened. One month before admission he felt chest squeezing at rest in the early morning. He presented at our institution to evaluate his chest symptoms. Electrocardiography and echocardiography failed to show any specific changes. Because of the possibility that his chest symptoms were due to myocardial ischemia, he was admitted to our institution for coronary angiography (CAG). An initial CAG showed mild atherosclerotic changes in the proximal segment of the left anterior descending coronary artery (LAD) and mid-segment of the left circumflex coronary artery. Subsequent spasm provocation testing using acetylcholine revealed a bilateral coronary vasospasm, which was relieved after the intracoronary infusion of nitroglycerin. Finally, a CAG showed myocardial bridging (MB) of the mid-distal segments of the LAD. Fractional flow reserve using the intravenous administration of adenosine triphosphate was positive at 0.77, which jumped up to 0.90 through the myocardial bridging segments when the pressure wire was pulled back. Thus, coronary vasospasm and MB might have contributed to his chest symptoms at rest and during effort. Interventional cardiologists should consider the presence of MB as a potential cause of myocardial ischemia. PMID:26131343

  13. Myocardial uptake of thallium and rubidium during alterations in perfusion and oxygenation in isolated rabbit hearts

    SciTech Connect

    Leppo, J.A.

    1987-05-01

    The comparative effects of altered cellular function and coronary perfusion on myocardial /sup 201/Tl and /sup 83/Rb uptake were evaluated in three groups of isolated rabbit hearts having isovolumic contractions. Paired-indication dilution experiments were performed with /sup 201/Tl, /sup 83/Rb, and /sup 111/In-labeled albumin as an intravascular reference marker. In Group A hearts (n = 12), isotope transport was determined during control, hypoxia, and ischemia. In Group B hearts (n = 8), isotope transport was measured at control flow and again at a 50% and 80% reduction. In Group C hearts (n = 8) only /sup 201/Tl uptake was determined at control and following coronary reperfusion. Myocardial /sup 201/Tl and /sup 83/Rb transport were not significantly different and were proportional to flow. Although all interventions caused significant hemodynamic alterations, neither tracer was affected by hypoxia at constant flow. Thallium-201 permeation, however, was transiently decreased immediately after coronary reperfusion. We conclude that myocardial uptake of /sup 201/Tl and /sup 83/Rb are similar and directly related to flow, but do not reflect hypoxia induced cellular dysfunction.

  14. Myocardial Reloading After Extracorporeal Membrane Oxygenation Alters Substrate Metabolism While Promoting Protein Synthesis

    PubMed Central

    Kajimoto, Masaki; O'Kelly Priddy, Colleen M.; Ledee, Dolena R.; Xu, Chun; Isern, Nancy; Olson, Aaron K.; Rosiers, Christine Des; Portman, Michael A.

    2013-01-01

    Background Extracorporeal membrane oxygenation (ECMO) unloads the heart, providing a bridge to recovery in children after myocardial stunning. ECMO also induces stress which can adversely affect the ability to reload or wean the heart from the circuit. Metabolic impairments induced by altered loading and/or stress conditions may impact weaning. However, cardiac substrate and amino acid requirements upon weaning are unknown. We assessed the hypothesis that ventricular reloading with ECMO modulates both substrate entry into the citric acid cycle (CAC) and myocardial protein synthesis. Methods and Results Sixteen immature piglets (7.8 to 15.6 kg) were separated into 2 groups based on ventricular loading status: 8‐hour ECMO (UNLOAD) and postwean from ECMO (RELOAD). We infused into the coronary artery [2‐13C]‐pyruvate as an oxidative substrate and [13C6]‐L‐leucine as an indicator for amino acid oxidation and protein synthesis. Upon RELOAD, each functional parameter, which were decreased substantially by ECMO, recovered to near‐baseline level with the exclusion of minimum dP/dt. Accordingly, myocardial oxygen consumption was also increased, indicating that overall mitochondrial metabolism was reestablished. At the metabolic level, when compared to UNLOAD, RELOAD altered the contribution of various substrates/pathways to tissue pyruvate formation, favoring exogenous pyruvate versus glycolysis, and acetyl‐CoA formation, shifting away from pyruvate decarboxylation to endogenous substrate, presumably fatty acids. Furthermore, there was also a significant increase of tissue concentrations for all CAC intermediates (≈80%), suggesting enhanced anaplerosis, and of fractional protein synthesis rates (>70%). Conclusions RELOAD alters both cytosolic and mitochondrial energy substrate metabolism, while favoring leucine incorporation into protein synthesis rather than oxidation in the CAC. Improved understanding of factors governing these metabolic perturbations may

  15. Mechanical Chest Compressions in Prolonged Cardiac Arrest due to ST Elevation Myocardial Infarction Can Cause Myocardial Contusion.

    PubMed

    Stechovsky, Cyril; Hajek, Petr; Cipro, Simon; Veselka, Josef

    2016-09-01

    Acute coronary syndrome is a common cause of sudden cardiac death. We present a case report of a 60-year-old man without a history of coronary artery disease who presented with ST-elevation myocardial infarction. During transportation to the hospital, he developed ventricular fibrillation (VF) and later pulseless electrical activity. Chest compressions with LUCAS 2 (Medtronic, Minneapolis, MN) automated mechanical compression-decompression device were initiated. Coronary angiography showed total occlusion of the left main coronary artery and primary percutaneous coronary intervention (PCI) was performed. After the PCI, his heart started to generate effective contractions and LUCAS could be discontinued. Return of spontaneous circulation was achieved after 90 minutes of cardiac arrest. The patient died of cardiogenic shock 11 hours later. An autopsy revealed a transmural anterolateral myocardial infarction but also massive subepicardial hemorrhage and interstitial edema and hemorrhages on histologic samples from regions of the myocardium outside the infarction itself and also from the right ventricle. These lesions were concluded to be a myocardial contusion. The true incidence of myocardial contusion as a consequence of mechanical chest compressions is not known. We speculate that severe myocardial contusion might have influenced outcome of our patient. PMID:27574387

  16. Acute myocardial infarction due to vasospasm in a 13-year-old-boy.

    PubMed

    Hosoi, T; Koyama, Y; Tange, S; Sumino, H; Kawai, Y; Kumakura, H; Takayama, Y; Ichikawa, S; Imai, S; Suzuki, T

    1997-06-01

    We describe an unusual case of acute myocardial infarction due to vasospasm in a 13-year-old boy. He was admitted to our hospital with severe congestive heart failure and shock. He had experienced a feeling of chest oppression with dyspnea while running, which grew worse. He then lost consciousness and was brought by ambulance to our intensive care unit. He had had similar but milder episodes of chest oppression months earlier. The family history revealed that his father had died suddenly from hypertrophic cardiomyopathy and that his grandmother also had hypertrophic cardiomyopathy. On admission, the patient was bathed in a cold sweat, his pulse was weak, and his blood pressure was too low to measure. Coarse crackling and wheezing were audible in both lung fields. Administration of catecholamine and intra-aortic balloon pumping failed to stabilize the hemodynamic variables, but percutaneous cardiopulmonary support proved to be lifesaving. Coronary arteriography performed during his convalescence showed on evidence of atherosclerosis. The acetylcholine provocation test ultimately revealed a diagnosis of acute myocardial infarction due to vasospasm. PMID:9225201

  17. Permeability alteration due to mineral dissolution in partially saturated fractures

    NASA Astrophysics Data System (ADS)

    Detwiler, Russell L.

    2010-09-01

    During reactive fluid flow in saturated fractures, the relative rates of dissolved mineral transport and local reactions strongly influence local aperture alterations and the resulting changes in fracture permeability (or transmissivity). In the presence of an entrapped residual nonaqueous phase (e.g., CO2 or oil), the spatial distribution of the entrapped phase will influence flow and transport and thus, local aperture alterations. These aperture alterations will in turn alter the balance of forces acting on immobile regions of the trapped phase. The resulting mobilization of the entrapped phase may subsequently alter flow pathways and fracture transmissivity in a manner that defies quantification with currently used constitutive relationships. I present results from quantitative visualization experiments in which fracture aperture and entrapped phase distribution were directly measured at high spatial resolution (75 × 75 μm) during reactive fluid flow. The experiments differed only in the orientation of the fracture with respect to gravity, which influenced both the initial entrapped phase geometry and the evolution of the entrapped phase as dissolution altered fracture apertures. The presence of the entrapped phase leads to a much earlier formation of distinct dissolution channels than has been observed in saturated fractures. Compared to a similar experiment in a fully saturated fracture, dissolution in the partially saturated fractures leads to as much as a 6-fold increase in transmissivity after an equal amount of dissolution from the fracture surface (doubling of the mean fracture aperture). Furthermore, the relative influence of gravity determines whether trapped bubbles mobilize because of capillary forces (against prevailing viscous forces) or gravitational forces, which is in the direction of prevailing viscous forces for the experiments presented here.

  18. Predictive Factors of Hospital Mortality Due to Myocardial Infarction: A Multilevel Analysis of Iran's National Data

    PubMed Central

    Ahmadi, Ali; Soori, Hamid; Mehrabi, Yadollah; Etemad, Koorosh; Sajjadi, Homeira; Sadeghi, Mehraban

    2015-01-01

    Background: Regarding failure to establish the statistical presuppositions for analysis of the data by conventional approaches, hierarchical structure of the data as well as the effect of higher-level variables, this study was conducted to determine the factors independently associated with hospital mortality due to myocardial infarction (MI) in Iran using a multilevel analysis. Methods: This study was a national, hospital-based, and cross-sectional study. In this study, the data of 20750 new MI patients between April, 2012 and March, 2013 in Iran were used. The hospital mortality due to MI was considered as the dependent variable. The demographic data, clinical and behavioral risk factors at the individual level and environmental data were gathered. Multilevel logistic regression models with Stata software were used to analyze the data. Results: Within 1-year of study, the frequency (%) of hospital mortality within 30 days of admission was derived 2511 (12.1%) patients. The adjusted odds ratio (OR) of mortality with (95% confidence interval [CI]) was derived 2.07 (95% CI: 1.5–2.8) for right bundle branch block, 1.5 (95% CI: 1.3–1.7) for ST-segment elevation MI, 1.3 (95% CI: 1.1–1.4) for female gender, and 1.2 (95% CI: 1.1–1.3) for humidity, all of which were considered as risk factors of mortality. But, OR of mortality was 0.7 for precipitation (95% CI: 0.7–0.8) and 0.5 for angioplasty (95% CI: 0.4–0.6) were considered as protective factors of mortality. Conclusions: Individual risk factors had independent effects on the hospital mortality due to MI. Variables in the province level had no significant effect on the outcome of MI. Increasing access and quality to treatment could reduce the mortality due to MI. PMID:26730342

  19. Acute Myocardial Infarction Due to Spontaneous Dissection of the Right Coronary Artery in a Young Male

    SciTech Connect

    Papadopoulos, Dimitris P. Moyssakis, Ioannis; Perakis, Alexandros; Athanasiou, Andreas; Anagnostopoulou, Sophia; Benos, Ioannis; Votteas, Vassilios E.

    2004-09-15

    Spontaneous coronary artery dissection is a rare cause of acute myocardial infarction. We report a case of a 33-year-old male who presented with an acute inferior myocardial infarction. Coronary arteriography performed 3 hours after the episode revealed a dissection involving the middle segment of right coronary artery. Because of a spiral form of dissection and the TIMI 3 flow grade, our patient was treated medically and repeat coronary angiography 6 months later was decided.

  20. Prenatal methamphetamine differentially alters myocardial sensitivity to ischemic injury in male and female adult hearts.

    PubMed

    Rorabaugh, Boyd R; Seeley, Sarah L; Bui, Albert D; Sprague, Lisanne; D'Souza, Manoranjan S

    2016-02-15

    Methamphetamine is one of the most common illicit drugs abused during pregnancy. The neurological effects of prenatal methamphetamine are well known. However, few studies have investigated the potential effects of prenatal methamphetamine on adult cardiovascular function. Previous work demonstrated that prenatal cocaine exposure increases sensitivity of the adult heart to ischemic injury. Methamphetamine and cocaine have different mechanisms of action, but both drugs exert their effects by increasing dopaminergic and adrenergic receptor stimulation. Thus the goal of this study was to determine whether prenatal methamphetamine also worsens ischemic injury in the adult heart. Pregnant rats were injected with methamphetamine (5 mg·kg(-1)·day(-1)) or saline throughout pregnancy. When pups reached 8 wk of age, their hearts were subjected to ischemia and reperfusion by means of a Langendorff isolated heart system. Prenatal methamphetamine had no significant effect on infarct size, preischemic contractile function, or postischemic recovery of contractile function in male hearts. However, methamphetamine-treated female hearts exhibited significantly larger infarcts and significantly elevated end-diastolic pressure during recovery from ischemia. Methamphetamine significantly reduced protein kinase Cε expression and Akt phosphorylation in female hearts but had no effect on these cardioprotective proteins in male hearts. These data indicate that prenatal methamphetamine differentially affects male and female sensitivity to myocardial ischemic injury and alters cardioprotective signaling proteins in the adult heart. PMID:26683901

  1. Hydrologic property alterations due to elevated temperatures at Yucca Mountain

    SciTech Connect

    Flint, A.L.; Nash, M.H.; Nash, M.S.

    1994-12-31

    Yucca Mountain is currently being evaluated as a potential site for a high level nuclear waste repository. The pre-emplacement hydrologic properties of the rock are important in determining the suitability of the site; however, post emplacement thermal loads and associated drying may permanently alter the character of the rock. A preliminary study was undertaken to determine the effects of elevated temperatures on hydrologic properties of the welded Topopah Spring member of the Paintbrush Tuff and a zeolitic, nonwelded tuff from the Tuffaceous Beds of Calico Hills. Rock outcrop samples were collected and dried in the laboratory at different temperatures (up to 400 degrees C). Hydrologic and physical properties -were tested before and after each of the drying cycles.

  2. Intraventricular flow alterations due to dyssynchronous wall motion

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  3. Concentrated Ambient Particles Alter Myocardial Blood Flow during Acute Ischemia in Conscious Canines

    PubMed Central

    Bartoli, Carlo R.; Wellenius, Gregory A.; Coull, Brent A.; Akiyama, Ichiro; Diaz, Edgar A.; Lawrence, Joy; Okabe, Kazunori; Verrier, Richard L.; Godleski, John J.

    2009-01-01

    Background Experimental and observational studies have demonstrated that short-term exposure to ambient particulate matter (PM) exacerbates myocardial ischemia. Objectives We conducted this study to investigate the effects of concentrated ambient particles (CAPs) on myocardial blood flow during myocardial ischemia in chronically instrumented conscious canines. Methods Eleven canines were instrumented with a balloon occluder around the left anterior descending coronary artery and catheters for determination of myocardial blood flow using fluorescent microspheres. Telemetric electrocardiographic and blood pressure monitoring was available for four of these animals. After recovery, we exposed animals by inhalation to 5 hr of either filtered air or CAPs (mean concentration ± SD, 349.0 ± 282.6 μg/m3) in a crossover protocol. We determined myocardial blood flow during a 5-min coronary artery occlusion immediately after each exposure. Data were analyzed using mixed models for repeated measures. The primary analysis was based on four canines that completed the protocol. Results CAPs exposure decreased total myocardial blood flow during coronary artery occlusion by 0.12 mL/min/g (p < 0.001) and was accompanied by a 13% (p < 0.001) increase in coronary vascular resistance. Rate–pressure product, an index of myocardial oxygen demand, did not differ by exposure (p = 0.90). CAPs effects on myocardial blood flow were significantly more pronounced in myocardium within or near the ischemic zone versus more remote myocardium (p interaction < 0.001). Conclusions These results suggest that PM exacerbates myocardial ischemia by increased coronary vascular resistance and decreased myocardial perfusion. Further studies are needed to elucidate the mechanism of these effects. PMID:19337504

  4. Acute myocardial infarction due to left anterior descending coronary artery dissection after blunt chest trauma.

    PubMed

    Oghlakian, Gerard; Maldjian, Pierre; Kaluski, Edo; Saric, Muhamed

    2010-03-01

    Cardiac complications of chest trauma range from arrhythmias to valvular avulsions to myocardial contusion, rupture, and rarely myocardial infarction. We describe a case of a young patient with blunt chest trauma after a motor vehicle accident in whom the diagnosis of myocardial infarction was established a week later because no electrocardiogram or cardiac biomarkers were obtained on presentation. Retrospective review of contrast-enhanced computed tomography (CT) of the chest done on presentation demonstrated a perfusion defect in the distribution of the left anterior descending artery (LAD). Subsequent coronary angiography demonstrated dissection in the proximal LAD. Our case illustrates the importance of electrocardiography and contrast-enhanced chest CT in initial evaluation of patients with blunt chest trauma and suspected injury to the coronary arteries. PMID:19214607

  5. Catecholamines and myocardial contractile function during hypodynamia and with an altered thyroid hormone balance

    NASA Technical Reports Server (NTRS)

    Pruss, G. M.; Kuznetsov, V. I.; Zhilinskaya, A. A.

    1980-01-01

    The dynamics of catecholamine content and myocardial contractile function during hypodynamia were studied in 109 white rats whose motor activity was severely restricted for up to 30 days. During the first five days myocardial catecholamine content, contractile function, and physical load tolerance decreased. Small doses of thyroidin counteracted this tendency. After 15 days, noradrenalin content and other indices approached normal levels and, after 30 days, were the same as control levels, although cardiac functional reserve was decreased. Thyroidin administration after 15 days had no noticeable effect. A detailed table shows changes in 17 indices of myocardial contractile function during hypodynamia.

  6. Pseudo-acute myocardial infarction due to transient apical ventricular dysfunction syndrome (Takotsubo syndrome)

    PubMed Central

    Maciel, Bruno Araújo; Cidrão, Alan Alves de Lima; Sousa, Ítalo Bruno dos Santos; Ferreira, José Adailson da Silva; Messias Neto, Valdevino Pedro

    2013-01-01

    Takotsubo syndrome is characterized by predominantly medial-apical transient left ventricular dysfunction, which is typically triggered by physical or emotional stress. The present article reports the case of a 61-year-old female patient presenting with dizziness, excessive sweating, and sudden state of ill feeling following an episode involving intense emotional stress. The physical examination and electrocardiogram were normal upon admission, but the troponin I and creatine kinase-MB concentrations were increased. Acute myocardial infarction without ST segment elevation was suspected, and coronary angiography was immediately performed, which showed severe diffuse left ventricular hypokinesia, medial-apical systolic ballooning, and a lack of significant coronary injury. The patient was referred to the intensive care unit and was successfully treated with supportive therapy. As this case shows, Takotsubo syndrome might simulate the clinical manifestations of acute myocardial infarction, and coronary angiography is necessary to distinguish between both myocardial infarction and myocardial infarction in the acute stage. The present patient progressed with spontaneous resolution of the ventricular dysfunction without any sequelae. PMID:23887762

  7. Lingual Haematoma due to Tenecteplase in a Patient with Acute Myocardial Infarction

    PubMed Central

    Bal, Muhlis; Salturk, Ziya; Ateş, Ahmet Hakan; Yağcı, Serkan; Coşkun Bal, Gökçen

    2013-01-01

    The use of intravenous thrombolytic agents has revolutionised the treatment of acute myocardial infarction. However, the improvement in mortality rate achieved with these drugs is tempered by the risk of serious bleeding complications, including intracranial haemorrhage. Tenecteplase is a genetically engineered mutant tissue plasminogen activator. Haemorrhagic complications of tissue plasminogen activator (tPA) are well known. Compared to other tPAs, tenecteplase use leads to lower rates of bleeding complications. Here, we report a case of unusual site of spontaneous bleeding, intralingual haematoma during tenecteplase therapy following acute myocardial infarction, which caused significant upper airway obstruction and required tracheotomy to maintain the patient's airway. Clinical dilemmas related to securing the airway or reversing the effects of tissue plasminogen activator are discussed. PMID:23862086

  8. Targeted Regional Injection of Biocomposite Microspheres Alters Post Myocardial Infarction Remodeling and Matrix Proteolytic Pathways

    PubMed Central

    Dixon, Jennifer A.; Gorman, Robert C.; Stroud, Robert E.; Mukherjee, Rupak; Meyer, Evan C.; Baker, Nathaniel L.; Morita, Masato; Hamamoto, Hirotsugu; Ryan, Liam P.; Gorman, Joseph H.; Spinale, Francis G.

    2011-01-01

    Background While localized delivery of biocomposite materials, such as calcium hydroxyapatite (CHAM), have been demonstrated to potentially attenuate adverse LV remodeling post-myocardial infarction (MI), the underlying biological mechanisms for this effect remain unclear. This study tested the hypothesis that targeted CHAM injections would alter proteolytic pathways (matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs)), and be associated with parameters of post-MI LV remodeling. Methods and Results MI was induced in adult sheep followed by 20 targeted injections of a total volume of 1.3 mL (n=6) or 2.6 mL of CHAM (n=5), or saline (n=13), and LV end-diastolic volume (EDV) and MMP/TIMP profiles in the MI region were measured at 8 weeks post-MI. LV EDV decreased with 2.6 mL CHAM vs MI Only (105.4±7.5 vs 80.6±4.2 respectively, p<0.05) but not with 1.3 mL CHAM (94.5±5.0, p=0.32). However, MI thickness increased by 2-fold in both CHAM groups compared to MI Only (p<0.05). MMP-13 increased 40-fold in the MI Only group (p<0.05) but fell by over 6-fold in both CHAM groups (p<0.05). MMP-7 increased approximately 1.5-fold in the MI Only group (p<0.05) but decreased to referent control values in both CHAM groups in the MI region (p<0.05). Collagen content was reduced by approximately 30% in the CHAM groups compared to MI Only (p<0.05). Conclusions Differential effects on LV remodeling and MMP/TIMP profiles occurred with CHAM. Thus, targeted injections of a biocomposite material can favorably affect the post-MI remodeling process and therefore holds promise as a treatment strategy in and of itself, or as a matrix with potentially synergistic effects with localized pharmacologic or cellular therapies. PMID:21911817

  9. Time dependent alterations of serum matrix metalloproteinase-1 and metalloproteinase-1 tissue inhibitor after successful reperfusion of acute myocardial infarction.

    PubMed Central

    Hirohata, S.; Kusachi, S.; Murakami, M.; Murakami, T.; Sano, I.; Watanabe, T.; Komatsubara, I.; Kondo, J.; Tsuji, T.

    1997-01-01

    OBJECTIVE: To test the hypothesis that changes in serum matrix metalloproteinase-1 (MMP-1) and tissue inhibitors of metalloproteinase-1 (TIMP-1) after acute myocardial infarction reflect extracellular matrix remodelling and the infarct healing process. PATIENTS: 13 consecutive patients with their first acute myocardial infarction who underwent successful reperfusion. METHODS: Blood was sampled on the day of admission, and on days 2, 3, 4, 5, 7, 14, and 28. Serum MMP-1 and TIMP-1 were measured by one step sandwich enzyme immunoassay. Left ventricular volume indices were determined by left ventriculography performed four weeks after the infarct. RESULTS: Serum concentrations of both MMP-1 and TIMP-1 changed over time. The average serum MMP-1 was more than 1 SD below the mean control values during the initial four days, increased thereafter, reaching a peak concentration around day 14, and then returned to the middle control range. Negative correlations with left ventricular end systolic volume index and positive correlations with left ventricular ejection fraction were obtained for serum MMP-1 on day 5, when it began to rise, and for the magnitude of rise in MMP-1 on day 5 compared to admission. Serum TIMP-1 at admission was more than 1 SD below the mean control value, and increased gradually thereafter, reaching a peak on around day 14. Negative correlations with left ventricular end systolic volume index and positive correlations with left ventricular ejection fraction were obtained for serum TIMP-1 on days 5 and 7, and for the magnitude of rise in TIMP-1 on days 5 and 7 compared to admission. CONCLUSIONS: Both MMP-1 and TIMP-1 showed significant time dependent alteration after acute myocardial infarction. Thus MMP-1 and TIMP-1 may provide useful information in evaluating the healing process as it affects left ventricular remodelling after acute myocardial infarction. PMID:9391291

  10. Diabetes-Induced Alterations in the Extracellular Matrix and Their Impact on Myocardial Function

    PubMed Central

    Law, Brittany; Fowlkes, Vennece; Goldsmith, Jack G.; Carver, Wayne; Goldsmith, Edie C.

    2014-01-01

    Diabetes is an increasing public health problem that is expected to escalate in the future due to the growing incidence of obesity in the western world.While this disease is well known for its devastating effects on the kidneys and vascular system, diabetic individuals can develop cardiac dysfunction, termed diabetic cardiomyopathy, in the absence of other cardiovascular risk factors such as hypertension or atherosclerosis. While much effort has gone into understanding the effects of elevated glucose or altered insulin sensitivity on cellular components within the heart, significant changes in the cardiac extracellular matrix (ECM) have also been noted. In this review article we highlight what is currently known regarding the effects diabetes has on both the expression and chemical modification of proteins within the ECM and how the fibrotic response often observed as a consequence of this disease can contribute to reduced cardiac function. PMID:22221857

  11. Acute Myocardial Infarction in a Young Lady due to Vitamin B12 Deficiency Induced Hyperhomocysteinemia

    PubMed Central

    Shamkani, Warkaa Al; Jafar, Nagham Saeed; Narayanan, Sunil Roy; Rajappan, Anil Kumar

    2015-01-01

    Hyper-homocysteinemia is a risk factor for coronary artery disease in young patients. A 32 years old female without any conventional risk factors except obesity presented with acute anterior wall myocardial infarction (MI). Her echocardiography showed anterior wall hypokinesia with moderate left ventricular dysfunction. Angiography showed tight stenosis of the proximal left anterior descending (LAD) and borderline lesion in left circumflex coronary artery (LCX). She underwent percutaneous coronary intervention (PCI) to LAD with good result. Her blood tests showed low vitamin B12, folate and serum iron levels and elevated serum homocysteine level. She was given folic acid and vitamin B12 and her homocysteine levels normalized. This case demonstrates that hyperhomocysteinemia caused by nutritional deficiency of vitamin co factors may lead to MI. Hyperhomocysteinemia should be considered in the evalauation of young people with MI, especially those without conventional risk factors. PMID:25838876

  12. [Cardiac Angiosarcoma with Acute Myocardial Infarction due to Tumor Embolism;Report of a Case].

    PubMed

    Date, Yusuke; Miyazu, Katsuyuki; Ikeda, Masahiro

    2016-09-01

    We report the case of a 28-year-old man with a rare angiosarcoma complicated by acute myocardial infarction secondary to tumor embolism. He was transported to our emergency unit because of sudden onset of chest pain. The echocardiography showed a 42×60 mm mass in the left ventricle, and the coronary angiography showed embolic occlusion of the proximal left anterior descending and circumflex arteries. Emergent surgical removal of the mass was attempted under cardiopulmonary bypass, concomitant with double coronary artery bypass grafting and mitral valve replacement with a mechanical prosthesis. However, complete tumor excision was impossible. The postoperative pathological examination revealed undifferentiated angiosarcoma. Twenty days after the operation, the patient suffered acute cerebral hemorrhage from a metastatic tumor in the brain. He died at 37 days after the initial cardiac surgery. PMID:27586319

  13. Acute myocardial infarction due to coronary thrombosis caused by blunt chest trauma.

    PubMed

    Treuth, Gregory M; Baibars, Motaz; Alraiyes, Abdul Hamid; Alraies, M Chadi

    2014-01-01

    A 65-year-old man presented to the emergency department following an anterior chest trauma. He had significant chest pain and chest X-ray was significant for revealed multiple rib fractures and negative. CT scan of the chest ruled out pulmonary embolism or aortic dissection. However, few hours later he developed hypotension requiring admission to medical intensive care unit and intravenous vasopressors. Further workup showed ST elevation myocardial infarction involving the anterior ECG leads. Emergent coronary angiography was performed with intervention to the mid-left anterior descending occlusion. Cardiogenic shock resolved and patient was discharged few days later. One-year follow-up with echocardiogram showed stable ischaemic cardiomyopathy with improved left ventricular ejection fraction to 50%. PMID:24769662

  14. Myocardial Reloading after Extracorporeal Membrane Oxygenation Alters Substrate Metabolism While Promoting Protein Synthesis

    SciTech Connect

    Kajimoto, Masaki; Priddy, Colleen M.; Ledee, Dolena; Xu, Chun; Isern, Nancy G.; Olson, Aaron; Des Rosiers, Christine; Portman, Michael A.

    2013-08-19

    Extracorporeal membrane oxygenation (ECMO) unloads the heart providing a bridge to recovery in children after myocardial stunning. Mortality after ECMO remains high.Cardiac substrate and amino acid requirements upon weaning are unknown and may impact recovery. We assessed the hypothesis that ventricular reloading modulates both substrate entry into the citric acid cycle (CAC) and myocardial protein synthesis. Fourteen immature piglets (7.8-15.6 kg) were separated into 2 groups based on ventricular loading status: 8 hour-ECMO (UNLOAD) and post-wean from ECMO (RELOAD). We infused [2-13C]-pyruvate as an oxidative substrate and [13C6]-L-leucine, as a tracer of amino acid oxidation and protein synthesis into the coronary artery. RELOAD showed marked elevations in myocardial oxygen consumption above baseline and UNLOAD. Pyruvate uptake was markedly increased though RELOAD decreased pyruvate contribution to oxidative CAC metabolism.RELOAD also increased absolute concentrations of all CAC intermediates, while maintaining or increasing 13C-molar percent enrichment. RELOAD also significantly increased cardiac fractional protein synthesis rates by >70% over UNLOAD. Conclusions: RELOAD produced high energy metabolic requirement and rebound protein synthesis. Relative pyruvate decarboxylation decreased with RELOAD while promoting anaplerotic pyruvate carboxylation and amino acid incorporation into protein rather than to the CAC for oxidation. These perturbations may serve as therapeutic targets to improve contractile function after ECMO.

  15. 7-oxo-PGI2 induced late protective action from arrhythmias due to local myocardial ischemia.

    PubMed

    Udvary, E; Végh, A; Szekeres, L

    1991-01-01

    In our earlier experiments administration of the stable PGI2 analogue: 7-oxo-PGI2-ephedrine salt to dogs resulted in a late appearing and long-lasting protection from coronary ligation induced ischemia and subsequent postocclusion and reperfusion arrhythmias. Objective of the present study was to evaluate the extent and duration of antiischemic and antiarrhythmic action induced by a single dose 50 micrograms/kg i.m. 7-oxo-PGI2 in dogs subjected to myocardial ischemia evoked by left anterior descending coronary (LAD) ligation at different intervals (2, 6, 24, 48, 72 hours and 2 weeks) after treatment. In the 2 weeks prolonged treatment group treatment started with 50 micrograms/kg i.m. dose, followed every third day by administration of 25 micrograms/kg 7-oxo-PGI2. After anesthesia and thoracotomy the electrophysiological parameters (SCL, CSNRT, AFRP, VFRP and A-V ERP) were determined by means of computer controlled programmed electrical stimulation. Then the animals were subjected to LAD occlusion for 25 min and subsequent reperfusion. 7-oxo-PGI2 pretreatment considerably protected against myocardial ischemia, i.e. there was a marked reduction in ST-segment elevation, the number of ES and the incidence of VF. The maximal antiischemic action and the most striking reduction in ventricular arrhythmias could be observed 48 hours after a single dose of 7-oxo-PGI2 and also after prolonged treatment of two weeks. In this latter group CSNRT showed the most expressed prolongation, however, AFRP and to lesser degree VFRP was also prolonged. PMID:2029655

  16. Alterations in myocardial energy metabolism induced by the anti-cancer drug doxorubicin.

    PubMed

    Tokarska-Schlattner, Malgorzata; Wallimann, Theo; Schlattner, Uwe

    2006-09-01

    Doxorubicin and other anthracyclines are among the most potent chemotherapeutic drugs for the treatment of acute leukaemia, lymphomas and different types of solid tumours such as breast, liver and lung cancers. Their clinical use is, however, limited by the risk of severe cardiotoxicity, which can lead to irreversible congestive heart failure. There is increasing evidence that essential components of myocardial energy metabolism are among the highly sensitive and early targets of doxorubicin-induced damage. Here we review doxorubicin-induced detrimental changes in cardiac energetics, with an emphasis on the emerging importance of defects in energy-transferring and -signalling systems, like creatine kinase and AMP-activated protein kinase. PMID:16945832

  17. The Frequency and Significance of Silent Myocardial Ischemia Due to Hyoscine Butylbromide Use in Peripheral Angiography

    SciTech Connect

    Maher, Richard; Phillips-Hughes, Jane; Banning, Adrian; Boardman, Philip

    1999-09-15

    Purpose: Hyoscine-N-butylbromide (HB) is an anticholinergic drug used in digital subtraction angiography of the aortoiliac region because it decreases bowel gas movement artifact. HB also causes an increase in heart rate. We investigated whether this could cause silent myocardial ischemia (SMI) in susceptible patients during peripheral angiography. Methods: Thirty-six patients undergoing peripheral angiography were randomized into two groups, with 17 patients receiving 20 mg HB intraarterially during the angiogram and 19 patients receiving no drug. All patients were fitted with a Holter monitor that recorded the electrocardiogram before, during, and after the angiogram. Heart rate trends and ST segments were then analyzed. Results: Patients given HB had a statistically significant rise in heart rate compared with the control group. Although the difference was not statistically significant, two (12%) patients receiving HB had procedural ST depression compared with none in the control group. Pre- and postprocedural episodes of ST depression were common, occurring in 41% of patients receiving HB and 37% of patients receiving no drug, and were associated with an increase in heart rate. Conclusion: The infrequent episodes of procedural SMI, potentially caused by the positive chronotropic effects of HB, are probably insignificant when compared with the high frequency of SMI episodes occurring outside the procedure.

  18. Sudden death of a child from myocardial infarction due to arteritis of the left coronary trunk.

    PubMed

    Takahashi, Shirushi; Takada, Aya; Saito, Kazuyuki; Hara, Masaaki; Yoneyama, Katsumi; Nakanishi, Hiroaki; Takahashi, Kei; Moriya, Takuya; Funayama, Masato

    2015-01-01

    An eight-year-old Japanese boy developed abdominal pain, followed by convulsion and loss of consciousness. He was taken to an emergency room but could not be resuscitated. At autopsy, the left main coronary trunk (LMT) demonstrated an increase in caliber with severe luminal narrowing, and the left anterior descending branch (LAD) subsequent to the LMT showed severe stenosis. Microscopically, the intima of the LMT demonstrated severe fibrosis and infiltration of lymphocytes and histiocytes suggesting vasculitis, and the small lumen was occupied by a fresh thrombus. The LAD showed significant intimal thickening with strong lymphocytic inflammation at the edge of the thickening. The left ventricle showed widespread myocardial infarction in the recovery stage. There were no findings of atherosclerosis, vasculitis or fibrocellular changes in the ascending aorta or intravisceral arteries other than the LMT and the LAD under investigation. The increase in the caliber of the LMT and the limitation of arteritis to the LMT and the subsequent branch suggested Kawasaki disease (KD), but it was atypical that the patient had no clinical history consistent with KD. The present case showed no findings suggesting classical polyarteritis nodosa (cPAN) at the acute or scar stage in the other vessels being investigated, and cPAN in childhood is rare compared to KD. A nonspecific inflammatory reaction (single organ vasculitis, SOV) was also considered as a possible cause, but it is difficult to determine whether the cause of the coronary stenosis in the present case was SOV because the sampling of arteries was insufficient. If forensic pathologists make unusual findings suggesting vasculitis at autopsy, the collection of a sufficient number of vessels of various sizes is warranted. PMID:25239164

  19. Evidence Report: Risk of Crew Adverse Health Event Due to Altered Immune Response

    NASA Technical Reports Server (NTRS)

    Crucian, Brian; Sams, Clarence F.

    2013-01-01

    The Risk of Crew Adverse Health Event Due to Altered Immune Response is identified by the National Aeronautics and Space Administration (NASA) Human Research Program (HRP) as a recognized risk to human health and performance in space. The HRP Program Requirements Document (PRD) defines these risks. This Evidence Report provides a summary of the evidence that has been used to identify and characterize this risk. It is known that human immune function is altered in- and post-flight, but it is unclear at present if such alterations lead to increased susceptibility to disease. Reactivation of latent viruses has been documented in crewmembers, although this reactivation has not been directly correlated with immune changes or with observed diseases. As described in this report, further research is required to better characterize the relationships between altered immune response and susceptibility to disease during and after spaceflight. This is particularly important for future deep-space exploration missions.

  20. Myocardial MiR-30 downregulation triggered by doxorubicin drives alterations in β-adrenergic signaling and enhances apoptosis.

    PubMed

    Roca-Alonso, L; Castellano, L; Mills, A; Dabrowska, A F; Sikkel, M B; Pellegrino, L; Jacob, J; Frampton, A E; Krell, J; Coombes, R C; Harding, S E; Lyon, A R; Stebbing, J

    2015-01-01

    The use of anthracyclines such as doxorubicin (DOX) has improved outcome in cancer patients, yet associated risks of cardiomyopathy have limited their clinical application. DOX-associated cardiotoxicity is frequently irreversible and typically progresses to heart failure (HF) but our understanding of molecular mechanisms underlying this and essential for development of cardioprotective strategies remains largely obscure. As microRNAs (miRNAs) have been shown to play potent regulatory roles in both cardiovascular disease and cancer, we investigated miRNA changes in DOX-induced HF and the alteration of cellular processes downstream. Myocardial miRNA profiling was performed after DOX-induced injury, either via acute application to isolated cardiomyocytes or via chronic exposure in vivo, and compared with miRNA profiles from remodeled hearts following myocardial infarction. The miR-30 family was downregulated in all three models. We describe here that miR-30 act regulating the β-adrenergic pathway, where preferential β1- and β2-adrenoceptor (β1AR and β2AR) direct inhibition is combined with Giα-2 targeting for fine-tuning. Importantly, we show that miR-30 also target the pro-apoptotic gene BNIP3L/NIX. In aggregate, we demonstrate that high miR-30 levels are protective against DOX toxicity and correlate this in turn with lower reactive oxygen species generation. In addition, we identify GATA-6 as a mediator of DOX-associated reductions in miR-30 expression. In conclusion, we describe that DOX causes acute and sustained miR-30 downregulation in cardiomyocytes via GATA-6. miR-30 overexpression protects cardiac cells from DOX-induced apoptosis, and its maintenance represents a potential cardioprotective and anti-tumorigenic strategy for anthracyclines. PMID:25950484

  1. Spontaneous alterations in left ventricular regional wall motion after acute myocardial infarction.

    PubMed

    Shen, W F; Cui, L Q; Wang, M H; Gong, L S; Lesbre, J P

    1990-12-01

    For assessing the relationship between the left ventricular (LV) wall motion abnormalities and the status of residual flow to the infarcted region, the extent of coronary artery disease and one-year outcome, 60 patients with a first transmural, Q-wave myocardial infarction (MI) underwent serial echocardiographic examinations. The abnormal wall motion (AWM) score was calculated, and the cardiac events (death, reinfarction, severe ventricular arrhythmia or congestive heart failure) after discharge were recorded. The AWM score of the infarcted area was higher in patients with total occlusion than in those with subtotal occlusion (anterior MI: 14.6 +/- 2.4 vs 7.2 +/- 2.1; inferior MI: 9.7 +/- 2.1 vs 5.1 +/-1.2, all P less than 0.01). Regional wall motion of the noninfarcted area was preserved in patients with single vessel disease but decreased in those with multivessel disease. In patients who developed cardiac events in follow-up period a higher AWM (16.4 +/- 3.7) was found than in those who did not (8.9 +/- 3.1, P less than 0.05). A score of greater than 13 had a strong prediction of cardiac events after acute MI, with a sensitivity of 81%, specificity of 94% and positive predictive accuracy of 88%. PMID:2127245

  2. ALTERATIONS IN THE PERMEABILITY OF NEUROSPORA CRASSA DUE TO POLYENE ANTIBIOTICS

    PubMed Central

    Kinsky, Stephen C.

    1961-01-01

    Kinsky, Stephen C. (Washington University, St. Louis, Mo.). Alterations in the permeability of Neurospora crassa due to polyene antibiotics. J. Bacteriol. 82:889–897. 1961.—Thirty-three antibiotics and synthetic fungicides were examined for their effect on the growth and morphology of Neurospora crassa. Only the polyene antibiotics (nystatin, amphotericin B, and filipin) caused a decrease in the dry weight of mycelial mats, which was accompanied by the appearance of cytoplasmic constituents in the medium. The influence of polyene concentration, incubation time, mycelial age, various metabolic inhibitors, pH, and media composition on this phenomenon are described. The present evidence indicates that the polyenes exert their primarily fungicidal effect by an alteration of permeability, probably due to direct action on the membrane of sensitive organisms. PMID:14456208

  3. Altered myocardial metabolic adaptation to increased fatty acid availability in cardiomyocyte-specific CLOCK mutant mice.

    PubMed

    Peliciari-Garcia, Rodrigo A; Goel, Mehak; Aristorenas, Jonathan A; Shah, Krishna; He, Lan; Yang, Qinglin; Shalev, Anath; Bailey, Shannon M; Prabhu, Sumanth D; Chatham, John C; Gamble, Karen L; Young, Martin E

    2016-10-01

    A mismatch between fatty acid availability and utilization leads to cellular/organ dysfunction during cardiometabolic disease states (e.g., obesity, diabetes mellitus). This can precipitate cardiac dysfunction. The heart adapts to increased fatty acid availability at transcriptional, translational, post-translational and metabolic levels, thereby attenuating cardiomyopathy development. We have previously reported that the cardiomyocyte circadian clock regulates transcriptional responsiveness of the heart to acute increases in fatty acid availability (e.g., short-term fasting). The purpose of the present study was to investigate whether the cardiomyocyte circadian clock plays a role in adaptation of the heart to chronic elevations in fatty acid availability. Fatty acid availability was increased in cardiomyocyte-specific CLOCK mutant (CCM) and wild-type (WT) littermate mice for 9weeks in time-of-day-independent (streptozotocin (STZ) induced diabetes) and dependent (high fat diet meal feeding) manners. Indices of myocardial metabolic adaptation (e.g., substrate reliance perturbations) to STZ-induced diabetes and high fat meal feeding were found to be dependent on genotype. Various transcriptional and post-translational mechanisms were investigated, revealing that Cte1 mRNA induction in the heart during STZ-induced diabetes is attenuated in CCM hearts. At the functional level, time-of-day-dependent high fat meal feeding tended to influence cardiac function to a greater extent in WT versus CCM mice. Collectively, these data suggest that CLOCK (a circadian clock component) is important for metabolic adaption of the heart to prolonged elevations in fatty acid availability. This article is part of a Special Issue entitled: Heart Lipid Metabolism edited by G.D. Lopaschuk. PMID:26721420

  4. Comprehensive analysis of myocardial infarction due to left circumflex artery occlusion: comparison with infarction due to right coronary artery and left anterior descending artery occlusion

    SciTech Connect

    Huey, B.L.; Beller, G.A.; Kaiser, D.L.; Gibson, R.S.

    1988-11-01

    Forty consecutive patients with creatine kinase-MB confirmed myocardial infarction due to circumflex artery occlusion (Group 1) were prospectively evaluated and compared with 107 patients with infarction due to right coronary artery occlusion (Group 2) and 94 with left anterior descending artery occlusion (Group 3). All 241 patients underwent exercise thallium-201 scintigraphy, radionuclide ventriculography, 24 h Holter electrocardiographic (ECG) monitoring and coronary arteriography before hospital discharge and were followed up for 39 +/- 18 months. There were no significant differences among the three infarct groups in age, gender, number of risk factors, prevalence and type of prior infarction, Norris index, Killip class and frequency of in-hospital complications. Acute ST segment elevation was present in only 48% of patients in Group 1 versus 71 and 72% in Groups 2 and 3, respectively (p = 0.012), and 38% of patients with a circumflex artery-related infarct had no significant ST changes (that is, elevation or depression) on admission (versus 21 and 20% for patients in Groups 2 and 3, respectively) (p = 0.001). Abnormal R waves in lead V1 were more common in Group 1 than in Group 2 (p less than 0.003) as was ST elevation in leads I, aVL and V4 to V6 (p less than or equal to 0.048). These differences in ECG findings between Group 1 and 2 patients correlated with a significantly higher prevalence of posterior and lateral wall asynergy in the group with a circumflex artery-related infarct. Infarct size based on peak creatine kinase levels and multiple radionuclide variables was intermediate in Group 1 compared with that in Group 2 (smallest) and Group 3 (largest). During long-term follow-up, the probability of recurrent cardiac events was similar in the three infarct groups.

  5. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration.

    PubMed

    Shrestha, Uttam M; Seo, Youngho; Botvinick, Elias H; Gullberg, Grant T

    2015-11-01

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variation of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. These results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images. PMID:26450115

  6. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration

    SciTech Connect

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-10-09

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variation of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. We find these results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images.

  7. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration

    DOE PAGESBeta

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-10-09

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variationmore » of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. We find these results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images.« less

  8. Image Reconstruction in Higher Dimensions: Myocardial Perfusion Imaging of Tracer Dynamics with Cardiac Motion Due to Deformation and Respiration

    PubMed Central

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-01-01

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variation of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. These results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases due to redistribution of the counts over the cardiac-respiratory gates. However, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images. PMID:26450115

  9. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration

    NASA Astrophysics Data System (ADS)

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-11-01

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variation of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. These results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images.

  10. Altered oxido-reductive state in the diabetic heart: loss of cardioprotection due to protein disulfide isomerase.

    PubMed

    Toldo, Stefano; Boccellino, Mariarosaria; Rinaldi, Barbara; Seropian, Ignacio M; Mezzaroma, Eleonora; Severino, Anna; Quagliuolo, Lucio; Van Tassell, Benjamin W; Marfella, Raffaele; Paolisso, Giuseppe; Rossi, Francesco; Natarajan, Ramesh; Voelkel, Norbert; Abbate, Antonio; Crea, Filippo; Baldi, Alfonso

    2011-01-01

    Diabetes is associated with an increased risk of heart failure, in part explained by endoplasmic reticulum stress and apoptosis. Protein disulfide isomerase (PDI) prevents stressed cardiomyocytes apoptosis. We hypothesized that diabetes impairs PDI function by an alteration in its oxido-reductive state. Myocardial biopsies harvested from the anterolateral left ventricular wall from diabetic (n = 7) and nondiabetic (n = 8) patients were used to assess PDI expression and cardiomyocyte death. A mouse model of diabetes (streptozotocin injection, 130 mg/mL) was used to study PDI expression and its redox state after ischemia/reperfusion injury induced by 30-min occlusion of the left anterior coronary artery followed by reperfusion. Transthoracic echocardiography was performed to assess cardiac remodeling after 1 wk. Western blot analysis was used to analyze PDI expression, and methoxy-polyethyleneglycol-maleimide was used to assess its redox state. Dehydroascorbate (DHA) administration was used to restore the PDI redox state. Diabetic patients had a greater number of transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells than nondiabetic patients despite a greater myocardial PDI expression suggesting altered PDI function. Diabetic mice had a worse postinfarction remodeling associated with an altered PDI redox state. DHA treatment restored functional PDI redox state and ameliorated post-myocardial infarction remodeling. An increase in PDI levels with a paradoxical decrease of its active form occurs in the diabetic heart after ischemia and may explain the lack of protective effects of PDI in diabetes. Restoration of PDI redox state prevents adverse remodeling. The potential significance of these findings deserves to be validated in a clinical setting. PMID:21637911

  11. Memory deficits due to brain injury: unique PET findings and dream alterations.

    PubMed

    Nishida, Masaki; Nariai, Tadashi; Hiura, Mikio; Ishii, Kenji; Nishikawa, Toru

    2011-01-01

    The authors herein report the case of a young male with memory deficits due to a traumatic head injury, who presented with sleep-related symptoms such as hypersomnia and dream alterations. Although MRI and polysomnography showed no abnormalities, (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) and (11)C flumazenil (FMZ)-PET revealed findings consistent with cerebral damage to the affected temporal region. The memory deficit of the patient gradually improved in parallel with the relief of the sleep-related symptoms. FDG-PET showed considerable improvement in glucose metabolism when he had recovered, however, evidence of neural loss remained in the FMZ-PET findings. PMID:22674950

  12. Memory deficits due to brain injury: unique PET findings and dream alterations

    PubMed Central

    Nishida, Masaki; Nariai, Tadashi; Hiura, Mikio; Ishii, Kenji; Nishikawa, Toru

    2011-01-01

    The authors herein report the case of a young male with memory deficits due to a traumatic head injury, who presented with sleep-related symptoms such as hypersomnia and dream alterations. Although MRI and polysomnography showed no abnormalities, 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) and 11C flumazenil (FMZ)-PET revealed findings consistent with cerebral damage to the affected temporal region. The memory deficit of the patient gradually improved in parallel with the relief of the sleep-related symptoms. FDG-PET showed considerable improvement in glucose metabolism when he had recovered, however, evidence of neural loss remained in the FMZ-PET findings. PMID:22674950

  13. A hypoxic episode during cardiogenesis downregulates the adenosinergic system and alters the myocardial anoxic tolerance.

    PubMed

    Robin, Elodie; Marcillac, Fabrice; Raddatz, Eric

    2015-04-01

    To what extent hypoxia alters the adenosine (ADO) system and impacts on cardiac function during embryogenesis is not known. Ectonucleoside triphosphate diphosphohydrolase (CD39), ecto-5'-nucleotidase (CD73), adenosine kinase (AdK), adenosine deaminase (ADA), equilibrative (ENT1,3,4), and concentrative (CNT3) transporters and ADO receptors A1, A2A, A2B, and A3 constitute the adenosinergic system. During the first 4 days of development chick embryos were exposed in ovo to normoxia followed or not followed by 6 h hypoxia. ADO and glycogen content and mRNA expression of the genes were determined in the atria, ventricle, and outflow tract of the normoxic (N) and hypoxic (H) hearts. Electrocardiogram and ventricular shortening of the N and H hearts were recorded ex vivo throughout anoxia/reoxygenation ± ADO. Under basal conditions, CD39, CD73, ADK, ADA, ENT1,3,4, CNT3, and ADO receptors were differentially expressed in the atria, ventricle, and outflow tract. In H hearts ADO level doubled, glycogen decreased, and mRNA expression of all the investigated genes was downregulated by hypoxia, except for A2A and A3 receptors. The most rapid and marked downregulation was found for ADA in atria. H hearts were arrhythmic and more vulnerable to anoxia-reoxygenation than N hearts. Despite downregulation of the genes, exposure of isolated hearts to ADO 1) preserved glycogen through activation of A1 receptor and Akt-GSK3β-GS pathway, 2) prolonged activity and improved conduction under anoxia, and 3) restored QT interval in H hearts. Thus hypoxia-induced downregulation of the adenosinergic system can be regarded as a coping response, limiting the detrimental accumulation of ADO without interfering with ADO signaling. PMID:25632022

  14. Subdaily Hydrologic Alteration due to Hydropower Operations in the Bio-Bio river in Southern Chile

    NASA Astrophysics Data System (ADS)

    Olivares, M. A.; Fernandez, M.; Benavides, C.; Palma, R.

    2012-12-01

    Hydropower plants can inexpensively respond to short-term changes in power demand. This can cause fluctuating operations at a subdaily scale. This work includes an assessment of the degree of subdaily hydrologic alteration (SDHA) due to operation two reservoir hydropower plants in the Bio-Bio river in southern Chile. Alternative operational constraints in the form of minimum instream flows (MIFs) and maximum ramping rates (MRRs) were defined and included into an economic dispatch model for hydrothermal scheduling with hourly stages and a weekly horizon. The model minimizes weekly total costs -including thermal production costs, failure costs, and expected future cost of water- over the entire grid (Chile's Central Interconnected System). Subdaily hydrologic alteration was assessed by computing a set of indicators compiled by Zimmerman et al. (2010). These indicators are obtained from hourly time series for 24-hour periods. Assessment of SDHA was based on a comparison of the indicador values obtained for actual recent operations to those obtained for a natural subdaily flow regime derived from hydrologic techniques and flow gage records. Results showed that current operations cause a downstream subdaily flow regime which deviates significatly from its natural counterpart. In other words, hydropower operations cause a significant degree of subdaily hydrologic alteration in the Bio-Bio river. Environmental constraints were imposed to the downstream reservoir operations. MIFs constraints took values between 30% and 60% of historical monthly average flows, whereas MRRs were set to values between 14 m3/s/hour and 68 m3/s/hour. Results indicate that both types of constraints improve the indicators of subdaily hydrologic alteration. However, under MIF constraints alone, improvement is only observed during some seasons in the year. MRR constraints improve the indicators all year round. Additionally, it was observed that the effect of environmental constraints on the

  15. Alterations in the Osteocyte Lacunar-Canalicular Microenvironment due to Estrogen Deficiency

    PubMed Central

    Sharma, Divya; Ciani, Cesare; Ramirez Marin, Paula A.; Levy, Jessica D.; Doty, Stephen B.; Fritton, Susannah P.

    2012-01-01

    While reduced estrogen levels have been shown to increase bone turnover and induce bone loss, there has been little analysis of the effects of diminished estrogen levels on the lacunar-canalicular porosity that houses the osteocytes. Alterations in the osteocyte lacunar-canalicular microenvironment may affect the osteocyte’s ability to sense and translate mechanical signals, possibly contributing to bone degradation during osteoporosis. To investigate whether reduced estrogen levels affect the osteocyte microenvironment, this study used high-resolution microscopy techniques to assess the lacunar-canalicular microstructure in the rat ovariectomy (OVX) model of postmenopausal osteoporosis. Confocal microscopy analyses indicated that OVX rats had a larger effective lacunar-canalicular porosity surrounding osteocytes in both cortical and cancellous bone from the proximal tibial metaphysis, with little change in cortical bone from the diaphysis or cancellous bone from the epiphysis. The increase in the effective lacunar-canalicular porosity in the tibial metaphysis was not due to changes in osteocyte lacunar density, lacunar size, or the number of canaliculi per lacuna. Instead, the effective canalicular size measured using a small molecular weight tracer was larger in OVX rats compared to controls. Further analysis using scanning and transmission electron microscopy demonstrated that the larger effective canalicular size in the estrogen-deficient state was due to nanostructural matrix-mineral level differences like loose collagen surrounding osteocyte canaliculi. These matrix-mineral differences were also found in osteocyte lacunae in OVX, but the small surface changes did not significantly increase the effective lacunar size. The alterations in the lacunar-canalicular surface mineral or matrix environment appear to make OVX bone tissue more permeable to small molecules, potentially altering interstitial fluid flow around osteocytes during mechanical loading. PMID

  16. Myocardial Infarction-Associated Transcript, a Long Noncoding RNA, Is Overexpressed During Dilated Cardiomyopathy Due to Chronic Chagas Disease.

    PubMed

    Frade, Amanda Farage; Laugier, Laurie; Ferreira, Ludmila Rodrigues Pinto; Baron, Monique Andrade; Benvenuti, Luiz Alberto; Teixeira, Priscila Camillo; Navarro, Isabela Cunha; Cabantous, Sandrine; Ferreira, Frederico Moraes; da Silva Cândido, Darlan; Gaiotto, Fabio Antônio; Bacal, Fernando; Pomerantzeff, Pablo; Santos, Ronaldo Honorato Barros; Kalil, Jorge; Cunha-Neto, Edecio; Chevillard, Christophe

    2016-07-01

    Long noncoding RNAs (lncRNAs) modulate gene expression at the epigenetic, transcriptional, and posttranscriptional levels. Dysregulation of the lncRNA known as myocardial infarction-associated transcript (MIAT) has been associated with myocardial infarction. Chagas disease causes a severe inflammatory dilated chronic cardiomyopathy (CCC). We investigated the role of MIAT in CCC. A whole-transcriptome analysis of heart biopsy specimens and formalin-fixed, paraffin-embedded samples revealed that MIAT was overexpressed in patients with CCC, compared with subjects with noninflammatory dilated cardiomyopathy and controls. These results were confirmed in a mouse model. Results suggest that MIAT is a specific biomarker of CCC. PMID:26951817

  17. A protocol design for studying alterations of pharmacokinetic parameters due to pregnancy.

    PubMed

    Philipson, A

    1980-01-01

    A study protocol is described by means of which useful and pertinent information on possible alterations of pharmacokinetic parameters due to pregnancy can be investigated. Whenever any drug is prescribed to a pregnant woman for medical reasons, pharmacokinetic data for that drug can be obtained by determination of drug levels in urine, plasma or serum, or other possible tissues. The same data should later be obtained for an identical dose of the same drug given to the same woman after pregnancy. By comparing pharmacokinetic parameters in the same woman during pregnancy and after--when she serves as her own nonpregnant control--clinically and statistically significant differences may be discovered with a comparatively small patient material. As in each case the drug that is studied is prescribed for medical reasons, this protocol involves no undue risks for the pregnant woman or the fetus. PMID:7445992

  18. Structural alterations of the coronary arterial wall are associated with myocardial flow heterogeneity in type 2 diabetes mellitus

    PubMed Central

    Schindler, Thomas H.; Facta, Alvaro D.; Prior, John O.; Cadenas, Jerson; Zhang, Xiao-Li; Li, Yanjie; Sayre, James; Goldin, Jonathan

    2016-01-01

    Purpose To determine the relationship between carotid intima–media thickness (IMT), coronary artery calcification (CAC), and myocardial blood flow (MBF) at rest and during vasomotor stress in type 2 diabetes mellitus (DM). Methods In 68 individuals, carotid IMT was measured using high-resolution vascular ultrasound, while the presence of CAC was determined with electron beam tomography (EBT). Global and regional MBF was determined in milliliters per gram per minute with 13N-ammonia and positron emission tomography (PET) at rest, during cold pressor testing (CPT), and during adenosine (ADO) stimulation. Results There was neither a relationship between carotid IMT and CAC (r=0.10, p=0.32) nor between carotid IMT and coronary circulatory function in response to CPT and during ADO (r=−0.18, p=0.25 and r=0.10, p=0.54, respectively). In 33 individuals, EBT detected CAC with a mean Agatston-derived calcium score of 44±18. There was a significant difference in regional MBFs between territories with and without CAC at rest and during ADO-stimulated hyperemia (0.69±0.24 vs. 0.74±0.23 and 1.82±0.50 vs. 1.95±0.51 ml/g/min; p≤0.05, respectively) and also during CPT in DM but less pronounced (0.81±0.24 vs. 0.83±0.23 ml/g/min; p=ns). The increase in CAC was paralleled with a progressive regional decrease in resting as well as in CPT- and ADO-related MBFs (r=−0.36, p≤0.014; r=−0.46, p≤0.007; and r=−0.33, p≤0.041, respectively). Conclusions The absence of any correlation between carotid IMT and coronary circulatory function in type 2 DM suggests different features and stages of early atherosclerosis in the peripheral and coronary circulation. PET-measured MBF heterogeneity at rest and during vasomotor stress may reflect downstream fluid dynamic effects of coronary artery disease (CAD)-related early structural alterations of the arterial wall. PMID:18704406

  19. ST Segment Elevation Myocardial Infarction Due to Severe Ostial Left Main Stem Stenosis in a Patient with Syphilitic Aortitis.

    PubMed

    Predescu, L M; Zarma, L; Platon, P; Postu, M; Bucsa, A; Croitoru, M; Prodan, B; Chioncel, O; Deleanu, D

    2016-01-01

    Cardiovascular manifestations of tertiary syphilis infections are uncommon, but represent an important cause of mortality and morbidity. Syphilitic aortitis is characterized by aortic regurgitation, dilatation of ascending aorta and ostial coronary artery lesions. We report a case of 36 years old man admitted to our hospital for acute anterior ST segment elevation myocardial infarction complicated with cardiogenic shock (hypotension 75/50 mmHg). Transthoracic echocardiography revealed a dilated left ventricle with severe systolic dysfunction (ejection fraction = 25%), severe mitral regurgitation, moderate aortic regurgitation and mildly dilated ascending aorta. Coronary angiography showed a severe ostial lesion of left main coronary artery which was treated by urgent stent implantation and an intra-aortic contrapulsation balloon was implanted. Blood tests for syphilitic infection were positive. The patient was discharged with treatment including benzathine penicillin. In our case, we present an acute manifestation of a syphilitic ostial left main stenosis treated by primary percutaneous coronary intervention in acute myocardial infarction. Long term follow-up of the patient is crucial as a result of potential rapid in-stent restenosis caused by continuous infection of the ascending aorta. This case is particular because it shows that syphilitic aortitis can be diagnosed in acute settings, like ST segment elevation myocardial infarction. PMID:27141575

  20. Hesperidin blunts streptozotocin-isoproternol induced myocardial toxicity in rats by altering of PPAR-γ receptor.

    PubMed

    Agrawal, Yogeeta O; Sharma, Pankaj Kumar; Shrivastava, Birendra; Arya, Dharamvir Singh; Goyal, Sameer N

    2014-08-01

    Hesperidin has been shown to possess cardioprotective and anti-diabetic potential. Hitherto, its molecular mechanism on isoproterenol (ISO)-induced myocardial dysfunction in diabetes is still not explored. Hence, for the first time we sought to investigate whether hesperidin exerts any beneficial effect on the pathophysiology of myocardial infarction (MI) in diabetes through the PPAR-γ pathway by assessing a variety of indices e.g., apoptosis, hemodynamic, biochemical and histoarchitectural changes. Diabetes was induced by a single dose of STZ (50 mg/kg IP). Diabetic rats received either hesperidin (100 mg/kg/day orally), the PPAR-γ antagonist GW9662 (1 mg/kg/day IP), or both for 14 days with concurrent administration of ISO (85 mg/kg SC) on days 13 and 14. ISO-STZ rats resulted in severe myocardial dysfunction (decreased ±LVdP/dt and increased LVEDP). In addition, augmented myocardial thiobarbituric acid-reactive substances and serum troponin-I with a concomitant decrease in level of glutathione and activities of catalase, superoxide dismutase antioxidants with cardiac injury biomarkers creatine kinase-MB isoenzyme, lactate dehydrogenase were seen. Morphological studies of the ISO-STZ challenged myocardium exhibited severe necrosis, edema and inflammatory changes. In Western blot analysis, Bcl-2 and PPAR-γ expression were decreased where as Bax expression was significantly increased, suggesting role of apoptosis in myocardial dysfunction. Interestingly, hesperidin treatment positively modulated these parameters as validated by improved hemodynamic and left ventricular functions, fortified endogenous anti-oxidant defence system and improved structural integrity of the myocardium. However, significant effects were lowered in animals treated with hesperidin plus GW9662. Moreover, down-regulated PPAR-γ and Bcl-2 expressions in myocardial infarcted diabetic hearts were increased by hesperidin treatment. Hence, for the first time the present study suggests that

  1. Protection against Myocardial Ischemia-Reperfusion Injury at Onset of Type 2 Diabetes in Zucker Diabetic Fatty Rats Is Associated with Altered Glucose Oxidation

    PubMed Central

    Povlsen, Jonas Agerlund; Løfgren, Bo; Dalgas, Christian; Birkler, Rune Isak Dupont; Johannsen, Mogens; Støttrup, Nicolaj Brejnholt; Bøtker, Hans Erik

    2013-01-01

    Background Inhibition of glucose oxidation during initial reperfusion confers protection against ischemia-reperfusion (IR) injury in the heart. Mitochondrial metabolism is altered with progression of type 2 diabetes (T2DM). We hypothesized that the metabolic alterations present at onset of T2DM induce cardioprotection by metabolic shutdown during IR, and that chronic alterations seen in late T2DM cause increased IR injury. Methods Isolated perfused hearts from 6 (prediabetic), 12 (onset of T2DM) and 24 (late T2DM) weeks old male Zucker diabetic fatty rats (ZDF) and their age-matched heterozygote controls were subjected to 40 min ischemia/120 min reperfusion. IR injury was assessed by TTC-staining. Myocardial glucose metabolism was evaluated by glucose tracer kinetics (glucose uptake-, glycolysis- and glucose oxidation rates), myocardial microdialysis (metabolomics) and tissue glycogen measurements. Results T2DM altered the development in sensitivity towards IR injury compared to controls. At late diabetes ZDF hearts suffered increased damage, while injury was decreased at onset of T2DM. Coincident with cardioprotection, oxidation of exogenous glucose was decreased during the initial and normalized after 5 minutes of reperfusion. Metabolomic analysis of citric acid cycle intermediates demonstrated that cardioprotection was associated with a reversible shutdown of mitochondrial glucose metabolism during ischemia and early reperfusion at onset of but not at late type 2 diabetes. Conclusions The metabolic alterations of type 2 diabetes are associated with protection against IR injury at onset but detrimental effects in late diabetes mellitus consistent with progressive dysfunction of glucose oxidation. These findings may explain the variable efficacy of cardioprotective interventions in individuals with type 2 diabetes. PMID:23704975

  2. Hyperoxia causes oxygen free radical-mediated membrane injury and alters myocardial function and hemodynamics in the newborn.

    PubMed

    Bandali, K S; Belanger, M P; Wittnich, C

    2004-08-01

    Newborn children can be exposed to high oxygen levels (hyperoxia) for hours to days during their medical and/or surgical management, and they also can have poor myocardial function and hemodynamics. Whether hyperoxia alone can compromise myocardial function and hemodynamics in the newborn and whether this is associated with oxygen free radical release that overwhelms naturally occurring antioxidant enzymes leading to myocardial membrane injury was the focus of this study. Yorkshire piglets were anesthetized with pentobarbital sodium (65 mg/kg), intubated, and ventilated to normoxia. Once normal blood gases were confirmed, animals were randomly allocated to either 5 h of normoxia [arterial Po(2) (Pa(O(2))) = 83 +/- 5 mmHg, n = 4] or hyperoxia (Pa(O(2)) = 422 +/- 33 mmHg, n = 6), and myocardial functional and hemodynamic assessments were made hourly. Left ventricular (LV) biopsies were taken for measurements of antioxidant enzyme activities [superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT)] and malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) as an indicator of oxygen free radical-mediated membrane injury. Hyperoxic piglets suffered significant reductions in contractility (P < 0.05), systolic blood pressure (P < 0.03), and mean arterial blood pressure (P < 0.05). Significant increases were seen in heart rate (P < 0.05), whereas a significant 11% (P < 0.05) and 61% (P < 0.001) reduction was seen in LV SOD and GPx activities, respectively, after 5 h of hyperoxia. Finally, MDA and 4-HNE levels were significantly elevated by 45% and 38% (P < 0.001 and P = 0.02), respectively, in piglets exposed to hyperoxia. Thus, in the newborn, hyperoxia triggers oxygen free radical-mediated membrane injury together with an inability of the newborn heart to upregulate its antioxidant enzyme defenses while impairing myocardial function and hemodynamics. PMID:15277198

  3. Prognostic significance of ST-T segment alterations in patients with non-Q wave myocardial infarction.

    PubMed Central

    Ramires, J. A.; Serrano, C. V.; Solimene, M. C.; Moffa, P. J.; Caramelli, B.; Pileggi, F.

    1996-01-01

    OBJECTIVE: To determine whether, among patients with non-Q wave myocardial infarction, the characteristics of the segment ST-T shifts at presentation in the diagnostic electrocardiogram can identify those with more severe coronary artery disease and predict a poor clinical outcome. DESIGN: Prospective controlled clinical trial. SETTING: Primary referral medical centre. PATIENTS: 93 patients (mean (SD) 62.0 (7.5) years) were studied: 41 with non-Q wave myocardial infarction and T wave inversion and 52 with ST segment depression. Cardiac events and mortality rates were assessed over 42 months. Age, sex, risk factors, creatinine kinase MB isoenzyme peak, and left ventricular function were comparable. RESULTS: 31 patients with T wave inversion myocardial infarction (94.6%) had total occlusion of the infarct related artery, compared with 12 patients with ST segment depression myocardial infarction (26.7%) (P < 0.05). When compared with patients with T wave inversion, patients with ST segment depression had a higher incidence of cardiac events during the first month and in the 41 subsequent months: 9.6% and 30.8% v 0% (P < 0.01) and 9.8% (P < 0.02), respectively. For the same observation periods, the mortality rates in patients with T wave inversion were 4.9% and 7.3%, and in patients with ST segment depression they were 5.8% and 9.6%, respectively. CONCLUSION: These data suggest that during a non-Q wave myocardial infarction the presence of ST segment depression is related to higher rates of short and long term cardiac events when compared with T wave inversion--possibly because of a higher incidence of residual stenosis of the infarct related artery. PMID:8697161

  4. Alterations in myocardial perfusion during exercise after isosorbide dinitrate infusion in patients with coronary disease: assessment by thallium-201 scintigraphy

    SciTech Connect

    Tono, I.; Satoh, S.; Kanaya, T.; Komatani, A.; Takahashi, K.; Tsuiki, K.; Yasui, S.

    1986-03-01

    We studied the effect of intravenous isosorbide dinitrate (ISDN) on myocardial perfusion of patients with coronary artery disease, by using exercise thallium-201 (TI-201) myocardial scintigraphy. A control study was conducted initially to assess regional myocardial perfusion rate. Left ventricular myocardium was divided into six parts: anterior, lateral, apical, inferior, posterior, and septal segments. The segmental myocardial perfusion was characterized according to TI-201 initial uptake index (IUI) of relative distribution and redistribution index (RDI) of TI-201 washout. The normal limit of IUI and RDI was established from the data of 17 persons with normal coronary arteries, and then the IUI less than or equal to 84% and the RDI greater than or equal to 1.12 was defined as abnormal. Based on IUI and RDI, each segment was characterized into three types: A type = IUI less than or equal to 84%, RDI greater than or equal to 1.12; B type = IUI less than or equal to 84%, RDI less than 1.12; and C type = IUI greater than 84%, RDI less than 1.12. ISDN was given as a dose of 0.1 mg/kg/hr, and then treadmill testing was repeated for the same duration of exercise time using the same protocol as in the control period. The segments of A type showed a significant improvement in IUI and RDI after receiving ISDN infusion, while the B and C type segments showed no change. It was also shown that the improvement of IUI and RDI of the A type segments was not as marked in multivessel disease as in cases of single-vessel disease.

  5. DETECTING STREAM INVERTEBRATE COMMUNITY ALTERATION DUE TO MID TO LOW LEVELS OF WATERSHED LANDSCAPE MODIFICATION

    EPA Science Inventory

    As part of an investigation into the effects of watershed landscape alteration on stream ecosystems, quantitative invertebrate samples were collected from riffles in 26 second and third order south shore Lake Superior streams. Nonmetric multidimensional scaling (NMDS) ordination ...

  6. Alteration of Dentin-Enamel Mechanical Properties Due to Dental Whitening Treatments

    PubMed Central

    Zimmerman, B.; Datko, L.; Cupelli, M.; Alapati, S.; Dean, D.; Kennedy, M.

    2010-01-01

    The mechanical properties of dentin and enamel affect the reliability and wear properties of a tooth. This study investigated the influence of clinical dental treatments and procedures, such as whitening treatments or etching prior to restorative procedures. Both autoclaved and non-autoclaved teeth were studied in order to allow for both comparison with published values and improved clinical relevance. Nanoindentation analysis with the Oliver-Pharr model provided elastic modulus and hardness across the dentin-enamel junction (DEJ). Large increases were observed in the elastic modulus of enamel in teeth that had been autoclaved (52.0GPa versus 113.4GPa), while smaller increases were observed in the dentin (17.9GPa versus 27.9GPa). Likewise, there was an increase in the hardness of enamel (2.0GPa versus 4.3GPa) and dentin (0.5GPa versus 0.7GPa) with autoclaving. These changes suggested that the range of elastic modulus and hardness values previously reported in literature may be partially due to the sterilization procedures. Treatment of the exterior of non-autoclaved teeth with Crest Whitestrips™, Opalescence™ or UltraEtch™ caused changes in the mechanical properties of both the enamel and dentin. Those treated with Crest Whitestrips™ showed a reduction in the elastic modulus of enamel (55.3GPa to 32.7GPa) and increase in the elastic modulus of dentin (17.2GPa to 24.3GPa). Opalescence™ treatments did not significantly affect the enamel properties, but did result in a decrease in modulus of dentin (18.5GPa to 15.1GPa). Additionally, as expected, UltraEtch™ treatment decreased the modulus and hardness of enamel (48.7GPa to 38.0GPa and 1.9GPa to 1.5GPa, respectively) and dentin (21.4GPa to 15.0GPa and 1.9GPa to 1.5GPa, respectively). Changes in the mechanical properties were linked to altered protein concentration within the tooth, as evidenced by fluorescence microscopy and Fourier transform infrared spectroscopy. PMID:20346902

  7. Altered host cell-bacteria interaction due to nanoparticle interaction with a bacterial biofilm.

    PubMed

    Raftery, Tara D; Lindler, Heidi; McNealy, Tamara L

    2013-02-01

    Nanoparticle (NP) use in everyday applications creates the potential for NPs to enter the environment where, in aquatic systems, they are likely to settle on substrates and interact with microbial communities. Legionella pneumophila biofilms are found as part of microbial communities in both natural and man-made environments, especially in man-made cooling systems. The bacterium is the causative agent of Legionnaires' disease. Legionella requires a host cell for replication in the environment, and amoebae commonly serve as this host cell. Our previous work demonstrated significant changes in Legionella biofilm morphology after exposure to 0.7 μg/L gold NPs (AuNPs). Here, we investigate how these morphology changes alter host-bacteria interactions using Acanthamoeba polyphaga as a model. Host-bacteria-NP interactions are affected by NP characteristics. Biofilms exposed to 4- and 18-nm, citrate-capped, spherical AuNPs significantly altered the grazing ability of A. polyphaga, which was not observed in biofilms exposed to 24-nm polystyrene beads. Uptake and replication of NP-exposed planktonic L. pneumophila within A. polyphaga were not altered regardless of NP size or core chemistry. Nanomaterial effects on the interaction of benthic organisms and bacteria may be directly or, as shown here, indirectly dependent on bacterial morphology. NP contamination therefore may alter interactions in a normal ecosystem function. PMID:23052925

  8. Are Amygdalar Volume Alterations in Children with Tourette Syndrome Due to ADHD Comorbidity?

    ERIC Educational Resources Information Center

    Ludolph, Andrea G.; Pinkhardt, Elmar H.; van Elst, Ludger Tebartz; Libal, Gerhard; Ludolph, Albert C.; Fegert, Jorg M.; Kassubek, Jan

    2008-01-01

    Recent studies have shown that changes in the basal ganglia circuitry and limbic loops may play an important role both in Tourette syndrome (TS) and attention-deficit-hyperactivity disorder (ADHD). This study aimed to investigate in vivo possible morphological alterations of the amygdala as a key component of the limbic system. Amygdalar and total…

  9. Expression of phospholipase D isozymes in scar and viable tissue in congestive heart failure due to myocardial infarction.

    PubMed

    Dent, Melissa R; Singal, Tushi; Dhalla, Naranjan S; Tappia, Paramjit S

    2004-01-01

    The phospholipase D (PLD) associated with the cardiac sarcolemmal (SL) membrane hydrolyses phosphatidylcholine to produce phosphatidic acid, an important phospholipid signaling molecule known to influence cardiac function. The present study was undertaken to examine PLD isozyme mRNA expression, protein contents and activities in congestive heart failure (CHF) subsequent to myocardial infarction (MI). MI was induced in rats by occlusion of the left anterior descending coronary artery. At 8 weeks after the surgical procedure, hemodynamic assessment revealed that these experimental rats were at a moderate stage of CHF. Semi-quantitative reverse transcriptase-polymerase chain reaction revealed that PLD1 and PLD2 mRNA amounts were unchanged in viable left ventricular (LV) tissue of the failing heart. Furthermore, this technique demonstrated the presence of PLD1 and PLD2 mRNA in the scar tissue. While SL PLD1 and PLD2 protein contents were elevated in the viable LV tissue of the failing heart, SL PLD1 activity was significantly decreased, whereas SL PLD2 activity was significantly increased. On the other hand, although PLD1 protein was undetectable, PLD2 protein and activity were detected in the scar tissue. Our findings suggest that differential changes in PLD isozymes may contribute to the pathophysiology of CHF and may also be involved in the processes of scar remodeling. PMID:15601581

  10. New therapeutic approach to heart failure due to myocardial infarction based on targeting growth hormone-releasing hormone receptor

    PubMed Central

    Schally, Andrew V.; Takeuchi, Lauro M.; Popovics, Petra; Jaszberenyi, Miklos; Vidaurre, Irving; Zarandi, Marta; Cai, Ren-Zhi; Block, Norman L.; Hare, Joshua M.; Rick, Ferenc G.

    2015-01-01

    Background We previously showed that growth hormone-releasing hormone (GHRH) agonists are cardioprotective following myocardial infarction (MI). Here, our aim was to evaluate the in vitro and in vivo activities of highly potent new GHRH agonists, and elucidate their mechanisms of action in promoting cardiac repair. Methods and Results H9c2 cells were cultured in serum-free medium, mimicking nutritional deprivation. GHRH agonists decreased calcium influx and significantly improved cell survival. Rats with cardiac infarction were treated with GHRH agonists or placebo for four weeks. MI size was reduced by selected GHRH agonists (JI-38, MR-356, MR-409); this accompanied an increased number of cardiac c-kit+ cells, cellular mitotic divisions, and vascular density. One week post-MI, MR-409 significantly reduced plasma levels of IL-2, IL-6, IL-10 and TNF-α compared to placebo. Gene expression studies revealed favorable outcomes of MR-409 treatment partially result from inhibitory activity on pro-apoptotic molecules and pro-fibrotic systems, and by elevation of bone morphogenetic proteins. Conclusions Treatment with GHRH agonists appears to reduce the inflammatory responses post-MI and may consequently improve mechanisms of healing and cardiac remod eling by regulating pathways involved in fibrosis, apoptosis and cardiac repair. Patients with cardiac dysfunction could benefit from treatment with novel GHRH agonists. PMID:25797248

  11. Moderate ischemic mitral regurgitation after postero-lateral myocardial infarction in sheep alters left ventricular shear but not normal strain in the infarct and infarct borderzone

    PubMed Central

    Ge, Liang; Wu, Yife; Soleimani, Mehrdad; Khazalpour, Michael; Takaba, Kiyoaki; Tartibi, Mehrzad; Zhang, Zhihong; Acevedo-Bolton, Gabriel; Saloner, David A.; Wallace, Arthur W.; Mishra, Rakesh; Grossi, Eugene A.; Guccione, Julius M.; Ratcliffe, Mark B.

    2016-01-01

    Background Chronic ischemic mitral regurgitation (CIMR: MR) is associated with poor outcome. Left ventricular (LV) strain after postero-lateral myocardial infarction (MI) may drive LV remodeling. Although moderate CIMR has been previously shown to effect LV remodeling, the effect of CIMR on LV strain after postero-lateral MI remains unknown. We tested the hypothesis that moderate CIMR alters LV strain after postero-lateral MI. Methods/Results Postero-lateral MI was created in 10 sheep. Cardiac MRI with tags was performed 2 weeks before and 2, 8 and 16 weeks after MI. LV and right ventricular (RV) volumes were measured and regurgitant volume indexed to body surface area (BSA; RegurgVolume Index) calculated as the difference between LV and RV stroke volumes / BSA. Three-dimensional strain was calculated. Circumferential (Ecc)and longitudinal (Ell) strains were reduced in the infarct proper, MI borderzone (BZ) and remote myocardium 16 weeks after MI. In addition, radial circumferential (Erc) and radial longitudinal (Erl) shear strains were reduced in remote myocardium but increased in the infarct and BZ 16 weeks after MI. Of all strain components, however, only Erc was effected by RegurgVolume Index (p=0.0005). There was no statistically significant effect of RegurgVolume Index on Ecc, Ell, Erl, or circumferential longitudinal shear strain (Ecl). Conclusions Moderate CIMR alters radial circumferential shear strain after postero-lateral MI in the sheep. Further studies are needed to determine the effect of shear strain on myocyte hypertrophy and the effect of mitral repair on myocardial strain. PMID:26857634

  12. Cardiac contractile dysfunction during mild coronary flow reductions is due to an altered calcium-pressure relationship in rat hearts.

    PubMed Central

    Figueredo, V M; Brandes, R; Weiner, M W; Massie, B M; Camacho, S A

    1992-01-01

    Coronary artery stenosis or occlusion results in reduced coronary flow and myocardial contractile depression. At severe flow reductions, increased inorganic phosphate (Pi) and intracellular acidosis clearly play a role in contractile depression. However, during milder flow reductions the mechanism(s) underlying contractile depression are less clear. Previous perfused heart studies demonstrated no change of Pi or pH during mild flow reductions, suggesting that changes of intravascular pressure (garden hose effect) may be the mediator of this contractile depression. Others have reported conflicting results regarding another possible mediator of contractility, the cytosolic free calcium (Cai). To examine the respective roles of Cai, Pi, pH, and vascular pressure in regulating contractility during mild flow reductions, Indo-1 calcium fluorescence and 31P magnetic resonance spectroscopy measurements were performed on Langendorff-perfused rat hearts. Cai and diastolic calcium levels did not change during flow reductions to 50% of control. Pi demonstrated a close relationship with developed pressure and significantly increased from 2.5 +/- 0.3 to 4.2 +/- 0.4 mumol/g dry weight during a 25% flow reduction. pH was unchanged until a 50% flow reduction. Increasing vascular pressure to superphysiological levels resulted in further increases of developed pressure, with no change in Cai. These findings are consistent with the hypothesis that during mild coronary flow reductions, contractile depression is mediated by an altered relationship between Cai and pressure, rather than by decreased Cai. Furthermore, increased Pi and decreased intravascular pressure may be responsible for this altered calcium-pressure relationship during mild coronary flow reductions. PMID:1430205

  13. Imaging alterations due to squamous metaplasia in intracranial neurenteric cysts: A report of two cases.

    PubMed

    Watanabe, Nobuyuki; Akasaki, Yasuharu; Fujigasaki, Junko; Mori, Ryosuke; Aizawa, Daisuke; Ikeuchi, Satoshi; Murayama, Yuichi

    2016-06-01

    Intracranial neurenteric cysts are rare congenital abnormalities with a broad imaging spectrum, and therefore are occasionally mistaken for other common intracranial cysts such as epidermoid and arachnoid cysts. We report two cases of neurenteric cysts in the posterior cranial fossa that were initially mistaken for other types of cysts. They exhibited signal intensity alterations in magnetic resonance imaging with significant volume expansion during their long-term observation. Both cases received surgical treatment because of clinical deterioration. Histologically, the cysts were lined by flattened or cuboidal epithelium, occasionally showing squamous metaplasia. Xanthogranulomatous inflammation and accumulation of cholesterol clefts, dry keratin and proteinaceous substance were observed in the cysts. These findings may indicate that chronic inflammation in neurenteric cysts induces squamous metaplasia, keratinization and high proteinaceous content, and causes MRI signal intensity alterations and volume expansion. We propose that MRI signal intensity alterations in neurenteric cysts may be a warning sign of their volume expansions, and thus require closer follow-up imaging and eventually surgical treatment. PMID:27009777

  14. Risk of Crew Adverse Health Event Due to Altered Immune Response

    NASA Technical Reports Server (NTRS)

    Crucian, Brian; Kunz, Hawley; Sams, Clarence F.

    2015-01-01

    Determining the effect of space travel on the human immune system has proven to be extremely challenging. Limited opportunities for in-flight studies, varying mission durations, technical and logistical obstacles, small subject numbers, and a broad range of potential assays have contributed to this problem. Additionally, the inherent complexity of the immune system, with its vast array of cell populations, sub-populations, diverse regulatory molecules, and broad interactions with other physiological systems, makes determining precise variables to measure very difficult. There is also the challenge of determining the clinical significance of any observed immune alterations. Will such a change lead to disease, or is it a transient subclinical observation related to short-term stress? The effect of this problem may be observed by scanning publications associated with immunity and spaceflight, which began to appear during the 1970s. Although individually they are each valid studies, the comprehensive literature to date suffers from widely varying sampling methods and assay techniques, low subject counts, and sometimes a disparate focus on narrow aspects of immunity. The most clinically relevant data are derived from in-flight human studies, which have demonstrated altered cell-mediated immunity and reactivation of latent herpes viruses. Much more data are available from post-flight testing of humans, with clear evidence of altered cytokine production patterns, altered leukocyte distribution, continued latent viral reactivation, and evidence of dramatically altered virus-specific immunity. It is unknown if post-flight assessments relate to the in-flight condition or are a response to landing stress and readaptation. In-flight culture of cells has clearly demonstrated that immune cells are gravity-sensitive and display altered functional characteristics. It is unknown if these data are related to in vivo immune cell function or are an artifact of microgravity culture

  15. Alteration of interleaflet coupling due to compounds displaying rapid translocation in lipid membranes.

    PubMed

    Reigada, Ramon

    2016-01-01

    The spatial coincidence of lipid domains at both layers of the cell membrane is expected to play an important role in many cellular functions. Competition between the surface interleaflet tension and a line hydrophobic mismatch penalty are conjectured to determine the transversal behavior of laterally heterogeneous lipid membranes. Here, by a combination of molecular dynamics simulations, a continuum field theory and kinetic equations, I demonstrate that the presence of small, rapidly translocating molecules residing in the lipid bilayer may alter its transversal behavior by favoring the spatial coincidence of similar lipid phases. PMID:27596355

  16. Alteration of interleaflet coupling due to compounds displaying rapid translocation in lipid membranes

    PubMed Central

    Reigada, Ramon

    2016-01-01

    The spatial coincidence of lipid domains at both layers of the cell membrane is expected to play an important role in many cellular functions. Competition between the surface interleaflet tension and a line hydrophobic mismatch penalty are conjectured to determine the transversal behavior of laterally heterogeneous lipid membranes. Here, by a combination of molecular dynamics simulations, a continuum field theory and kinetic equations, I demonstrate that the presence of small, rapidly translocating molecules residing in the lipid bilayer may alter its transversal behavior by favoring the spatial coincidence of similar lipid phases. PMID:27596355

  17. Reciprocal white matter alterations due to 16p11.2 chromosomal deletions versus duplications.

    PubMed

    Chang, Yi Shin; Owen, Julia P; Pojman, Nicholas J; Thieu, Tony; Bukshpun, Polina; Wakahiro, Mari L J; Marco, Elysa J; Berman, Jeffrey I; Spiro, John E; Chung, Wendy K; Buckner, Randy L; Roberts, Timothy P L; Nagarajan, Srikantan S; Sherr, Elliott H; Mukherjee, Pratik

    2016-08-01

    Copy number variants at the 16p11.2 chromosomal locus are associated with several neuropsychiatric disorders, including autism, schizophrenia, bipolar disorder, attention-deficit hyperactivity disorder, and speech and language disorders. A gene dosage dependence has been suggested, with 16p11.2 deletion carriers demonstrating higher body mass index and head circumference, and 16p11.2 duplication carriers demonstrating lower body mass index and head circumference. Here, we use diffusion tensor imaging to elucidate this reciprocal relationship in white matter organization, showing widespread increases of fractional anisotropy throughout the supratentorial white matter in pediatric deletion carriers and, in contrast, extensive decreases of white matter fractional anisotropy in pediatric and adult duplication carriers. We find associations of these white matter alterations with cognitive and behavioral impairments. We further demonstrate the value of imaging metrics for characterizing the copy number variant phenotype by employing linear discriminant analysis to predict the gene dosage status of the study subjects. These results show an effect of 16p11.2 gene dosage on white matter microstructure, and further suggest that opposite changes in diffusion tensor imaging metrics can lead to similar cognitive and behavioral deficits. Given the large effect sizes found in this study, our results support the view that specific genetic variations are more strongly associated with specific brain alterations than are shared neuropsychiatric diagnoses. Hum Brain Mapp 37:2833-2848, 2016. © 2016 Wiley Periodicals, Inc. PMID:27219475

  18. Detection of time-varying harmonic amplitude alterations due to spectral interpolations between musical instrument tones.

    PubMed

    Horner, Andrew B; Beauchamp, James W; So, Richard H Y

    2009-01-01

    Gradated spectral interpolations between musical instrument tone pairs were used to investigate discrimination as a function of time-averaged spectral difference. All possible nonidentical pairs taken from a collection of eight musical instrument sounds consisting of bassoon, clarinet, flute, horn, oboe, saxophone, trumpet, and violin were tested. For each pair, several tones were generated with different balances between the primary and secondary instruments, where the balance was fixed across the duration of each tone. Among primary instruments it was found that changes to horn and bassoon [corrected] were most easily discriminable, while changes to saxophone and trumpet timbres were least discriminable. Among secondary instruments, the clarinet had the strongest effect on discrimination, whereas the bassoon had the least effect. For primary instruments, strong negative correlations were found between discrimination and their spectral incoherences, suggesting that the presence of dynamic spectral variations tends to increase the difficulty of detecting time-varying alterations such as spectral interpolation. PMID:19173434

  19. Degeneration of Dopaminergic Neurons Due to Metabolic Alterations and Parkinson’s Disease

    PubMed Central

    Song, Juhyun; Kim, Jongpil

    2016-01-01

    The rates of metabolic diseases, such as type 2 diabetes mellitus (T2DM), obesity, and cardiovascular disease (CVD), markedly increase with age. In recent years, studies have reported an association between metabolic changes and various pathophysiological mechanisms in the central nervous system (CNS) in patients with metabolic diseases. Oxidative stress and hyperglycemia in metabolic diseases lead to adverse neurophysiological phenomena, including neuronal loss, synaptic dysfunction, and improper insulin signaling, resulting in Parkinson’s disease (PD). In addition, several lines of evidence suggest that alterations of CNS environments by metabolic changes influence the dopamine neuronal loss, eventually affecting the pathogenesis of PD. Thus, we reviewed recent findings relating to degeneration of dopaminergic neurons during metabolic diseases. We highlight the fact that using a metabolic approach to manipulate degeneration of dopaminergic neurons can serve as a therapeutic strategy to attenuate pathology of PD. PMID:27065205

  20. Pathological alterations due to motile Aeromonas infection in red swordtail fish (Xiphophorus helleri).

    PubMed

    Bunnajirakul, S; Pavasutthipaisit, S; Steinhagen, D

    2015-01-01

    A herd of red swordtail fish (Xiphophorus helleri) was reared in outdoor concrete ponds and suffered from occasional mortality. Moribund fishes showing abdominal dropsy and fin rots were sent for diagnosis. Gross necropsy findings showed enlargement of liver, spleen, and kidney in concurrence with congestion, and a severe accumulation of peritoneal fluid. Histopathological findings revealed an alteration of hepatocytes, with a severe diffuse accumulation of fat vacuoles in the cytoplasm. In the trunk kidney, severe accumulation of mononuclear cells together with cloudy swelling of the renal tubular epithelium was observed. From internal organs of the fish motile Aeromonas spp. were identified. The pathological findings might be associated with a long-term infection of affected fish fostered by common stressors such as improper feeding and poor pond environment condition (water temperature). Effective therapeutic measures comprised an advancement of keeping conditions and appropriate feeding to improve the health status in combination with the application of antibiotic substances. PMID:26527040

  1. Alteration of IGFBP-1 in soccer players due to intensive training.

    PubMed

    Lagundžin, Dragana; Vucić, Vesna; Glibetić, Marija; Nedić, Olgica

    2013-10-01

    Physical activity is accompanied by the changes in Insulin-like Growth Factor I (IGF-I)/IGF-Binding Protein 1 (IGFBP-1) axis. Inconsistent results concerning IGF-I and IGFBP-1 levels were reported. In this study we have raised some questions on the events that occur at the molecular level of the exercise-related IGFBP-1 changes. We have examined the fragmentation pattern of IGFBP-1, IGFBP-1 protease activity, interaction between IGFBP-1 and alpha2-macroglobulin (α2M), and possible existence of minor structural changes of IGFBP-1 in professional soccer players. Athletes had significantly greater amounts of fragmented IGFBP-1, whereas no difference was found in the amount of intact IGFBP-1 compared with controls. An increased activity of matrix metalloprotease-9 (MMP-9) was detected in athletes, causing IGFBP-1 degradation down to the fragment of 9 kDa as the major one. The amount of α2M, which protects IGFBP-1 from proteolysis, or the amount of IGFBP-1/α2M complexes was unaltered. Finally, we have examined whether IGFBP-1 isolated from soccer players exhibited altered reactivity with several chemical surfaces used in surface-enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF MS). Different reactivity was detected with anion and cation exchangers, suggesting existence of at least one sequence within IGFBP-1, whose ionization pattern was not equal in athletes and controls. Differences in spectra obtained with ion exchanges may reflect differences in IGFBP-1 phosphorylation. Physiological implications of the events described in this study on the IGF-I availability are, at this time, unknown. It can be hypothesized that IGFBP-1 proteolysis leads to altered distribution of IGF-I among IGFBPs, which may affect the final IGF-associated response. PMID:23535908

  2. Alterations in myocardial metabolism and function at rest in stable angina pectoris: relations with the amount of exercise-induced thallium-201 perfusion defect

    SciTech Connect

    De Kock, M.; Melin, J.A.; Pouleur, H.; Rousseau, M.F.

    1986-01-01

    The relation between the amount of exercise-induced ischemia and alterations in left ventricular (LV) function and metabolism at rest was studied in 18 coronary patients with stable angina pectoris. An ischemic defect area score was computed from quantitative exercise thallium-201 (Tl-201) scintigraphy; this estimation of the amount of ischemic myocardium was used to classify the patients in group I (n = 8; score less than 15%, mean 6.7 +/- 2.5%) and II (n = 10; score greater than 15%; mean 27.2 +/- 8.9%). Hemodynamics and metabolism were studied in basal state. No patient had anginal pain during the study, and the extent of angiographic coronary artery disease (CAD) was comparable in the two groups. Heart rate, aortic pressure, coronary blood flow, and myocardial oxygen uptake were also similar in both groups. However, ejection fraction was reduced in group II (51 +/- 13 vs 63 +/- 5%; p less than 0.01) and LV relaxation was impaired as shown by the increase in time-constant of isovolumic pressure fall (55 +/- 16 vs 44 +/- 6 ms in group I; p less than 0.05); the LV end-diastolic pressure was also increased in group II (19 +/- 8 vs 10 +/- 4 mmHg in group l; p less than 0.05). Furthermore, in group II, myocardial lactate uptake was reduced (4 +/- 19 vs 30 +/- 29 mumole/min in group I; p less than 0.01) and the productions of alanine and glutamine were augmented (-7.5 +/- 4.4 vs -4.6 +/- 1.6 mumole/min in group I; p less than 0.05).

  3. Long-term prognosis of patients with acute myocardial infarction due to unprotected left main coronary artery disease: a single-centre experience over 14 years

    PubMed Central

    Xu, Li; Sun, Hao; Wang, Le-Feng; Yang, Xin-Chun; Li, Kui-Bao; Zhang, Da-Peng; Wang, Hong-Shi; Li, Wei-Ming

    2016-01-01

    INTRODUCTION Acute myocardial infarction (AMI) due to unprotected left main coronary artery (ULMCA) disease is clinically catastrophic although it has a low incidence. Studies on the long-term prognosis of these patients are rare. METHODS From January 1999 to September 2013, 55 patients whose infarct-related artery was the ULMCA were enrolled. Clinical, angiographic and interventional data was collected. Short-term and long-term clinical follow-up results as well as prognostic determinants during hospitalisation and follow-up were analysed. RESULTS Cardiogenic shock (CS) occurred in 30 (54.5%) patients. During hospitalisation, 22 (40.0%) patients died. Multivariate logistic regression analysis showed that CS (odds ratio [OR] 5.86; p = 0.03), collateral circulation of Grade 2 or 3 (OR 0.14; p = 0.02) and final flow of thrombolysis in myocardial infarction (TIMI) Grade 3 (OR 0.05; p = 0.03) correlated with death during hospitalisation. 33 patients survived to discharge; another seven patients died during the follow-up period of 44.6 ± 31.3 (median 60, range 0.67–117.00) months. The overall mortality rate was 52.7% (n = 29). Kaplan-Meier analysis showed that the total cumulative survival rate was 30.7%. Cox multivariate regression analysis showed that CS during hospitalisation was the only predictor of overall mortality (hazard ratio 4.07, 95% confidence interval 1.40–11.83; p = 0.01). CONCLUSION AMI caused by ULMCA lesions is complicated by high incidence of CS and mortality. CS, poor collateral blood flow and failure to restore final flow of TIMI Grade 3 correlated with death during hospitalisation. CS is the only predictor of long-term overall mortality. PMID:27439434

  4. Sap flow is Underestimated by Thermal Dissipation Sensors due to Alterations of Wood Anatomy

    NASA Astrophysics Data System (ADS)

    Marañón-Jiménez, S.; Wiedemann, A.; van den Bulcke, J.; Cuntz, M.; Rebmann, C.; Steppe, K.

    2014-12-01

    The thermal dissipation technique (TD) is one of the most commonly adopted methods for sap flow measurements. However, underestimations of up to 60% of the tree transpiration have been reported with this technique, although the causes are not certainly known. The insertion of TD sensors within the stems causes damage of the wood tissue and subsequent healing reactions, changing wood anatomy and likely the sap flow path. However, the anatomical changes in response to the insertion of sap flow sensors and the effects on the measured flow have not been assessed yet. In this study, we investigate the alteration of vessel anatomy on wounds formed around TD sensors. Our main objectives were to elucidate the anatomical causes of sap flow underestimation for ring-porous and diffuse-porous species, and relate these changes to sap flow underestimations. Successive sets of TD probes were installed in early, mid and end of the growing season in Fagus sylvatica (diffuse-porous) and Quercus petraea (ring-porous) trees. They were logged after the growing season and additional sets of sensors were installed in the logged stems with presumably no healing reaction. The wood tissue surrounding each sensor was then excised and analysed by X-ray computed microtomography (X-ray micro CT). This technique allowed the quantification of vessel anatomical characteristics and the reconstruction of the 3-D internal microstructure of the xylem vessels so that extension and shape of the altered area could be determined. Gels and tyloses clogged the conductive vessels around the sensors in both beech and oak. The extension of the affected area was larger for beech although these anatomical changes led to similar sap flow underestimations in both species. The higher vessel size in oak may explain this result and, therefore, larger sap flow underestimation per area of affected conductive tissue. The wound healing reaction likely occurred within the first weeks after sensor installation, which

  5. Lysosomotropic agents selectively target chronic lymphocytic leukemia cells due to altered sphingolipid metabolism.

    PubMed

    Dielschneider, R F; Eisenstat, H; Mi, S; Curtis, J M; Xiao, W; Johnston, J B; Gibson, S B

    2016-06-01

    Lysosome membrane permeabilization (LMP) mediates cell death in a variety of cancer cells. However, little is known about lysosomes and LMP in chronic lymphocytic leukemia (CLL). Owing to drug resistance and toxicity in CLL patients, better treatment strategies are required. Our results show that CLL cells were sensitive to the lysosomotropic agent siramesine. Furthermore, this drug was more effective in CLL cells, regardless of prognostic factors, compared with normal B cells. Siramesine caused LMP, lipid peroxidation and transcription factor EB nuclear translocation followed by mitochondrial membrane potential loss and reactive oxygen species release. Siramesine-induced cell death was blocked by lipid antioxidants, but not by soluble antioxidants or protease inhibitors. To determine whether CLL cells had altered lysosomes, we investigated sphingolipid metabolism as the lysosome is a hub for lipid metabolism. We found that CLL cells had more lysosomes, increased sphingosine-1-phosphate phosphatase 1 (SPP1) expression, and increased levels of sphingosine compared with normal B cells. Raising sphingosine levels increased LMP and cell death in CLL cells, but not in normal B cells. Together, these results show that excess sphingosine in CLL cells could contribute to their sensitivity toward LMP. Thus, targeting the lysosome could be a novel therapeutic strategy in CLL. PMID:26859075

  6. An invasive macrophyte alters sediment chemistry due to suppression of a native isoetid.

    PubMed

    Urban, Rebecca A; Titus, John E; Zhu, Wei-Xing

    2006-06-01

    The submersed macrophyte Utricularia inflata (inflated bladderwort) is a recent invader of Adirondack Mountain lakes (NY, USA). A 15-week greenhouse experiment and a 7-week field experiment were conducted to test the hypothesis that this rootless species fundamentally changes sediment chemistry through its suppression of the native short-statured species, Eriocaulon aquaticum. E. aquaticum has an extensive root system that releases oxygen into the sediment. In greenhouse conditions, E. aquaticum raised the porewater redox potential of otherwise bare sediment from 25 to 324 mV, lowered the sediment porewater pH from 5.7 to 4.6, and depleted the dissolved inorganic carbon and ammonium concentrations in the sediment porewater by 68.4 and 96.0%, respectively (P<0.001 for all four parameters). A cover of U. inflata over E. aquaticum, however, greatly reduced the latter's effect on redox potential (P<0.001), dissolved solutes (P<0.001), and pH (P<0.05). E. aquaticum biomass increased during the greenhouse experiment in the absence of U. inflata, but decreased in its presence (P<0.001). Redox and growth rate results from the field experiment paralleled those from the greenhouse experiment. Our data suggest that U. inflata may change nutrient cycling in Adirondack lake ecosystems by reducing the growth of native isoetid macrophytes, such as E. aquaticum, and consequently altering key features of sediment chemistry. PMID:16518632

  7. Spatial and Temporal Alterations on Carbon and Water Cycles Due to Grazing

    NASA Astrophysics Data System (ADS)

    Maksimowicz, M. M.; Brunsell, N. A.; Ham, J. M.

    2009-05-01

    Grasslands are vital in the carbon cycle, as large amounts of carbon are stored in the soils of the prairie. As climate change affects the carbon cycle, it is essential for the agricultural communities to understand the impacts of these changes on farming practices such as grazing and meat production. The objective of this study is to determine the effect of grazing on the carbon cycle by characterizing the surface boundary layer of both a grazed field and an ungrazed field. Data were collected from open path eddy covariance systems over Rannells Flint Hills Prairie Preserve in north-central Kansas, one over an ungrazed field and one over a grazed field. Cospectra of fluxes of CO2, heat, water, and momentum for July 2007 were compared to assess the size of eddies contributing energy to each field. For CO2, the cospectra for both the ungrazed and the ungrazed field were similar. For all of the other fluxes, lower frequency eddies contributed more energy in the grazed field than the ungrazed field. By using a footprint model, the contributing source areas were determined for fluxes from May through October of 2007. The grazed field had a larger distance of contribution in both stable and unstable atmospheric conditions. Implications of this study include the alterations on fields and impacts on the carbon and water cycles as a result of grazing.

  8. The Asthenosphere Melting Regimes Alteration due to Changing Conditions of Upper Mantle

    NASA Astrophysics Data System (ADS)

    Perepechko, Y. V.; Sharapov, V. N.; Sorokin, K., Jr.

    2014-12-01

    Analyzed in the article are different asthenosphere magma generation regimes above the upper mantle hot spots as thermodynamic and geometric parameters of the upper mantle and the conditions on its boundaries vary. The two-layer mantle model is applied to consider the formation of decompression melting areas. The thickness of metasomatically altered lithospheric mantle is determined by the mantle substance rheology and the location of the upper boundary of asthenosphere. We also take into consideration the principal solid state phase transitions by using the mantle substance state equation. The sizes and distribution of hot spots as well as their maximal temperature were defined by the thermodynamic conditions of the perovskite transition existence. The numerical analysis results demonstrate the manifestation of three main mantle dynamics modes; the conditions necessary to form the partial melting zones are not reached; some melting areas with the 30 to 65 Ma existence time do occur; the melting areas that are formed exist permanently. The permanently existing asthenosphere zones are marked by quasiperiodical variation in thickness and the degree of melting. The typical temperatures of a hot spot sharing these modes are the 1740°С and 2020°С correspondingly. The originally presupposed heating degree and the temperature ratio of the upper mantle do influence the decompression melting degree substantially and - to a lesser extent - they influence the size of melting zones. The primary evolution of the second mode is described by the development of a complex system of asthenosphere zones that lead to the occurrence of additional convectional cells dividing the partial melting zone. The variation in the rheological properties of the mantle substance also contributes to the manifestation of the complex structure of asthenosphere zone. The work was made with support of the Russian Foundation for Basic Research grant #12-05-00625.

  9. Molecular cause and functional impact of altered synaptic lipid signaling due to a prg-1 gene SNP.

    PubMed

    Vogt, Johannes; Yang, Jenq-Wei; Mobascher, Arian; Cheng, Jin; Li, Yunbo; Liu, Xingfeng; Baumgart, Jan; Thalman, Carine; Kirischuk, Sergei; Unichenko, Petr; Horta, Guilherme; Radyushkin, Konstantin; Stroh, Albrecht; Richers, Sebastian; Sahragard, Nassim; Distler, Ute; Tenzer, Stefan; Qiao, Lianyong; Lieb, Klaus; Tüscher, Oliver; Binder, Harald; Ferreiros, Nerea; Tegeder, Irmgard; Morris, Andrew J; Gropa, Sergiu; Nürnberg, Peter; Toliat, Mohammad R; Winterer, Georg; Luhmann, Heiko J; Huai, Jisen; Nitsch, Robert

    2016-01-01

    Loss of plasticity-related gene 1 (PRG-1), which regulates synaptic phospholipid signaling, leads to hyperexcitability via increased glutamate release altering excitation/inhibition (E/I) balance in cortical networks. A recently reported SNP in prg-1 (R345T/mutPRG-1) affects ~5 million European and US citizens in a monoallelic variant. Our studies show that this mutation leads to a loss-of-PRG-1 function at the synapse due to its inability to control lysophosphatidic acid (LPA) levels via a cellular uptake mechanism which appears to depend on proper glycosylation altered by this SNP. PRG-1(+/-) mice, which are animal correlates of human PRG-1(+/mut) carriers, showed an altered cortical network function and stress-related behavioral changes indicating altered resilience against psychiatric disorders. These could be reversed by modulation of phospholipid signaling via pharmacological inhibition of the LPA-synthesizing molecule autotaxin. In line, EEG recordings in a human population-based cohort revealed an E/I balance shift in monoallelic mutPRG-1 carriers and an impaired sensory gating, which is regarded as an endophenotype of stress-related mental disorders. Intervention into bioactive lipid signaling is thus a promising strategy to interfere with glutamate-dependent symptoms in psychiatric diseases. PMID:26671989

  10. Myocardial ischemia due to compression of an unruptured thoracic aortic aneurysm in a patient with Marfan syndrome.

    PubMed

    Minami, Hiroya; Asada, Tatsuro; Gan, Kunio; Abe, Koichiro; Izumi, Satoshi

    2007-06-01

    We report a 33-year-old woman who had a 60-mm thoracic aneurysm of the ascending aorta with Marfan syndrome and effort angina due to compression of the right coronary artery (RCA) by the aneurysm. Surgery was performed using the Bentall procedure and a coronary artery bypass graft to the RCA. Postoperatively, coronary angiography showed that the coronary flow of the RCA was restored by removing the aneurysmal compression. The patient was discharged without angina on postoperative day 21. PMID:17642279

  11. Immunohistochemical detection of early myocardial damage in two sudden deaths due to intentional butane inhalation. Two case reports with review of literature.

    PubMed

    Novosel, Irena; Kovačić, Zdravko; Gusić, Stjepan; Batelja, Lovorka; Nestić, Marina; Seiwerth, Sven; Skavić, Josip

    2011-04-01

    The abuse of household and other commercially available products containing volatile organic solvents is underrecognized. Not infrequently intentional butane inhalation results in high morbidity and mortality. A fatal outcome of butane abuse can be caused by asphyxia, cardiac arrhythmia or trauma. The reported number of cases in which death was the consequence of pure butane inhalation is limited, and in most cases a mixture of propellants was involved. This report covers two cases of sudden death due to the sniffing of a cigarette lighter refill containing butane. Autopsy was followed by toxicological, pathohistological and immunohistochemical analysis. Butane gas was confirmed in samples of blood, urine, brain and lungs by the gas chromatography method - "headspace" technique. Histology showed almost identical changes in the lungs and heart in both cases. The morphology of heart damage on standard H/E stains was of special interest because it displayed all the characteristics of chronic and acute myocardial hypoxia found in the absence of atherosclerotic heart disease. In order to confirm early cardiac death caused by asphyxia due to butane inhalation a panel of immunohistochemical agents was used: Myoglobin, Desmin, Fibronectin, Fibrinogen and CC9. PMID:21420651

  12. Correcting oral contraceptive pharmacokinetic alterations due to obesity. A randomized controlled trial

    PubMed Central

    Edelman, Alison B; Cherala, Ganesh; Munar, Myrna Y.; McInnis, Martha; Stanczyk, Frank Z.; Jensen, Jeffrey T

    2014-01-01

    Objective To determine if increasing the hormone dose or eliminating the hormone-free interval improves key pharmacokinetic (PK) alterations caused by obesity during oral contraceptive (OC) use. Study design Obese (BMI ≥ 30 kg/m2), ovulatory, otherwise healthy, women received an OC containing 20 mcg ethinyl estradiol (EE)/100 mcg levonorgestrel (LNG) dosed cyclically (21 days active pills with 7-day placebo week) for two cycles and then were randomized for two additional cycles to: Continuous Cycling [CC, a dose neutral arm using the same OC with no hormone-free interval] or Increased Dose [ID, a dose escalation arm using an OC containing 30 mcg EE/150 mcg LNG cyclically]. During Cycle 2, 3, and 4, outpatient visits were performed to assess maximum serum concentration (Cmax), area under the curve (AUC0-∞), and time to steady state as well as pharmacodynamics. These key PK parameters were calculated and compared within groups between baseline and treatment cycles. Results A total of 31 women enrolled and completed the study (CC group n = 16; ID group n = 15). Demographics were similar between groups [mean BMI: CC 38kg/m2 (SD 5.1), ID 41kg/m2 (SD 7.6)]. At baseline, the key LNG PK parameters were no different between groups; average time to reach steady-state was 12 days in both groups; Cmax were CC: 3.82 ± 1.28 ng/mL and ID: 3.13 ± 0.87 ng/mL; and AUC0-∞ were CC: 267 ± 115 hr*ng/mL and ID: 199±75 hr*ng/mL. Following randomization, the CC group maintained steady-state serum levels whereas the ID group had a significantly higher Cmax (p< 0.001) but again required 12 days to achieve steady-state. However, AUC was not significantly different between CC (412 ± 255 hr*ng/mL) and ID (283 ± 130 hr*ng/mL). Forty-five percent (14/31) of the study population had evidence of an active follicle-like structure prior to randomization and afterwards this decreased to 9% (3/31). Conclusion Both increasing the OC dose and continuous dosing appear to counteract the impact

  13. Alterations in tissue glutathione and angiotensin converting enzyme due to inhalation of diesel engine exhaust

    SciTech Connect

    Chaudhari, A.; Dutta, S.

    1982-02-01

    Quantitative changes in reduced glutathione (GSH) and angiotensin converting enzyme (ACE) of lung and extrapulmonary tissues were determined following exposure of laboratory animals to diesel engine exhaust (DEE). Exposure of male rats and guinea pigs to DEE containing 750 ..mu..g particulates per cubic meter for 1 wk did not cause any changes in GSH levels of lung, liver, and heart compared to control values. Rats were then exposed for various time periods to 6 mg/m/sup 3/ DEE. Two weeks of exposure produced statistically significant increases of 21 and 7% in GSH levels of lung and liver, respectively, but no change in the heart. Following 4 wk of exposure, lung showed a 14% increase and heat an 11% increase in GSH level. Furthermore, rats exposed for 4 wk to DEE did not show any particular susceptibility toward the GSH-depleting effect of acetaminophen as compared to controls. A significant depletion (15%) of hepatic GSH was observed after 8 wk of exposure, while lung was still showing an increase of 18% in GSH and heart was unaffected. Time-dependent increases of 18 and 33% in serum ACE activity were noted after 4 and 8 wk of exposure. Pulmonary ACE activity did not decrease until after 8 wk, and then to a small extent (7%). The observed increases in GSH may have been related to the presence of NO/sub 2/ in the DEE. On the other hand, the depletion of hepatic GSH suggests production of electrophillic compounds due to an induction of metabolic activity of liver. The change in serum ACE activity may be due to time-requiring perturbations in the pulmonary endothelial cells.

  14. Alteration of Fractured Rocks Due to Coupled Chemical and Mechanical Processes: High-Resolution Simulations and Experimental Observations

    NASA Astrophysics Data System (ADS)

    Ameli, Pasha

    Engineering activities such as enhanced geothermal energy production and improved oil recovery techniques are heavily dependent on the permeability of the subsurface, while others such as CO2 sequestration and nuclear waste disposal rely on the efficiency of rock formations as transport barriers. In either case fractures provide the main pathways for fluid flow and transport, especially in rocks with lower matrix porosity. Laboratory experiments aimed at quantifying the chemo-mechanical responses of fractures have shown a range of results, some of which contradict simple conceptual models. For example, under conditions favoring mineral dissolution, where one would expect an overall increase in permeability, experiments show that permeability increases under some conditions and decreases under others. Recent experiments have attempted to link these core-scale observations to the relevant small-scale processes occurring within fractures. Results suggest that the loss of mechanical strength in asperities due to chemical alteration may cause non-uniform deformation and alteration of fracture apertures. However, due to the lack of direct micro-scale measurements of the coupled chemical and mechanical processes that lead to alteration of contacting fracture surfaces, our ability to predict the long-term evolution of fractures is still limited. To explore the processes that control permeability evolution, I developed a computational model that uses micro-scale surface roughness and explicitly couples dissolution and elastic deformation to calculate local alterations in fracture aperture under chemical and mechanical stresses. A depth-averaged algorithm of fracture flow is used to model reactive transport and chemical alteration of the fracture surfaces. Then, I deform the resulting altered fracture-surfaces using an algorithm that calculates the elastic deformation. The results of the model are compared with flow-through experiments conducted on fractured limestone. The

  15. Alterations in rat brain polyphosphoinositide metabolism due to acute ethanol administration.

    PubMed

    Chandrasekhar, R; Huang, H M; Sun, G Y

    1988-04-01

    The effects of acute ethanol administration on the polyphosphoinositide metabolism of rat brain cerebral cortex were examined. Intracerebral injections of [gamma-32P]ATP proved to be an effective in vivo method to prelabel brain phospholipids, especially the polyphosphoinositides. High acute doses of ethanol (8 or 6 g/kg b.wt.) administered by gavage significantly inhibited the breakdown of polyphosphoinositides as judged by an elevation in the concentration as well as the labeling of these compounds. Concomitantly, there was a significant reduction in the level of diacylglycerols. Low acute doses of ethanol (2 g/kg b.wt.) did not seem to have any effects on the basal levels or labeling of these compounds. The changes in polyphosphoinositide labeling due to ethanol intoxication were reverted to near control values when animals regained their righting reflex (approximately 4 hr). These studies demonstrate that, under normal conditions, polyphosphoinositides and diacylglycerols are maintained in a dynamic equilibrium and that acute doses of ethanol can suppress the signal transduction process and disturb this equilibrium. PMID:2834532

  16. Adaptation to altered balance conditions in unilateral amputees due to atherosclerosis: a randomized controlled study

    PubMed Central

    2011-01-01

    Background Amputation impairs the ability to balance. We examined adaptation strategies in balance following dysvascularity-induced unilateral tibial amputation in skilled prosthetic users (SPU) and first fitted amputees (FFA) (N = 28). Methods Excursions of center of pressure (COP) were determined during 20 s quiet standing using a stabilometry system with eyes-open on both legs or on the non-affected leg(s). Main measures: COP trajectories and time functions; distribution of reaction forces between the two legs; inclination angles obtained through second order regression analysis using stabilogram data. Results FFA vs SPU demonstrated 27.8% greater postural sway in bilateral stance (p = 0.0004). Postural sway area was smaller in FFA standing on the non-affected leg compared with SPU (p = 0.028). The slope of the regression line indicating postural stability was nearly identical in FFA and SPU and the direction of regression line was opposite for the left and right leg amputees. Conclusion Of the two adaptation strategies in balance, the first appears before amputation due to pain and fatigue in the affected leg. This strategy appears in the form of reduced postural sway while standing on the non-affected leg. The second adaptation occurs during rehabilitation and regular use of the prosthesis resulting in normal weightbearing associated with reduced postural sway on two legs and return to the normal postural stability on one leg. PMID:21619618

  17. Alteration of the oxygen-dependent reactivity of de novo Due Ferri proteins.

    PubMed

    Reig, Amanda J; Pires, Marcos M; Snyder, Rae Ana; Wu, Yibing; Jo, Hyunil; Kulp, Daniel W; Butch, Susan E; Calhoun, Jennifer R; Szyperski, Thomas; Szyperski, Thomas G; Solomon, Edward I; DeGrado, William F

    2012-11-01

    De novo proteins provide a unique opportunity to investigate the structure-function relationships of metalloproteins in a minimal, well-defined and controlled scaffold. Here, we describe the rational programming of function in a de novo designed di-iron carboxylate protein from the Due Ferri family. Originally created to catalyse the O(2)-dependent, two-electron oxidation of hydroquinones, the protein was reprogrammed to catalyse the selective N-hydroxylation of arylamines by remodelling the substrate access cavity and introducing a critical third His ligand to the metal-binding cavity. Additional second- and third-shell modifications were required to stabilize the His ligand in the core of the protein. These structural changes resulted in at least a 10(6)-fold increase in the relative rate between the arylamine N-hydroxylation and hydroquinone oxidation reactions. This result highlights the potential for using de novo proteins as scaffolds for future investigations of the geometric and electronic factors that influence the catalytic tuning of di-iron active sites. PMID:23089864

  18. The Kutta-Zhukovsky Lift Theorem revisited: Alteration due to the Viscous Wake

    NASA Astrophysics Data System (ADS)

    Schmitz, Sven

    2011-11-01

    The circulation theory of lift comprised in the classical Kutta-Zhukovsky Lift Theorem forms the foundation of modern aerodynamic wing theory. The theorem has been applied ever since in lifting-line models of aircraft and rotary wings. Reynolds numbers larger than one million support its validity, yet the effect of a viscous wake on a change in the functional relationship between lift and circulation is not taken into account in standard lifting-line analyses. A discrepancy in circulation of more than six percent in comparison to the classical Kutta-Zhukovsky Lift Theorem has been demonstrated by the author (Schmitz & Chattot, Computers & Fluids, 36) for moderately separated flow around a wind turbine airfoil by means of a control volume analysis governed by the Navier-Stokes equations. The present work extends the previous analysis to general three-dimensional flow around a lifting body. An analytical expression is presented that extends the classical Kutta-Zhukovsky Lift Theorem by adding terms to the theorem due to chord- and spanwise vorticity transport. An integrated solution for induced drag is given that has not been documented in previous literature on the subject. The generalized theorem will find future application and quantification in actuator-line methods used to predict wind farm wake interactions with Atmospheric Boundary Layer flow.

  19. An Altered Pattern of Myocardial Histopathological and Molecular Changes Underlies the Different Characteristics of Type-1 and Type-2 Diabetic Cardiac Dysfunction

    PubMed Central

    Radovits, Tamás; Korkmaz, Sevil; Mátyás, Csaba; Oláh, Attila; Páli, Szabolcs; Zubarevich, Alina; Gwanmesia, Patricia Neh; Li, Shiliang; Loganathan, Sivakkanan; Barnucz, Enikő; Merkely, Béla; Szabó, Gábor

    2015-01-01

    Increasing evidence suggests that both types of diabetes mellitus (DM) lead to cardiac structural and functional changes. In this study we investigated and compared functional characteristics and underlying subcellular pathological features in rat models of type-1 and type-2 diabetic cardiomyopathy. Type-1 DM was induced by streptozotocin. For type-2 DM, Zucker Diabetic Fatty (ZDF) rats were used. Left ventricular pressure-volume analysis was performed to assess cardiac function. Myocardial nitrotyrosine immunohistochemistry, TUNEL assay, hematoxylin-eosin, and Masson's trichrome staining were performed. mRNA and protein expression were quantified by qRT-PCR and Western blot. Marked systolic dysfunction in type-1 DM was associated with severe nitrooxidative stress, apoptosis, and fibrosis. These pathological features were less pronounced or absent, while cardiomyocyte hypertrophy was comparable in type-2 DM, which was associated with unaltered systolic function and increased diastolic stiffness. mRNA-expression of hypertrophy markers c-fos, c-jun, and β-MHC, as well as pro-apoptotic caspase-12, was elevated in type-1, while it remained unaltered or only slightly increased in type-2 DM. Expression of the profibrotic TGF-β1 was upregulated in type-1 and showed a decrease in type-2 DM. We compared type-1 and type-2 diabetic cardiomyopathy in standard rat models and described an altered pattern of key pathophysiological features in the diabetic heart and corresponding functional consequences. PMID:25629059

  20. Altered combustion characteristics of metallized energetics due to stable secondary material inclusion

    NASA Astrophysics Data System (ADS)

    Terry, Brandon C.

    Though metals and metalloids have been widely considered as reactive fuels, the ability to tune their ignition and combustion characteristics remains challenging. One means to accomplish this may be through low-level inclusion of secondary materials into the metallized fuel. While there are several potential methods to stably introduce secondary inclusion materials, this work focuses on the use of mechanical activation (MA) and metal alloys. Recent work has shown that low-level inclusion of fluoropolymers into aluminum particles can have a substantial effect on their combustion characteristics. The reflected shock ignition of mechanically activated aluminum/polytetrafluoroethylene (MA Al/PTFE) is compared to a physical mixture (PM) of Al/PTFE, neat spherical aluminum, and flake aluminum. It was found that the powders with higher specific surface areas ignited faster than the spherical particles of the same size, and had ignition delay times comparable to agglomerates of aluminum particles that were two orders of magnitude smaller in size. Flake aluminum powder had the same ignition delay as MA Al/PTFE, indicating that any initial aluminum/fluoropolymer reactions did not yield an earlier onset of aluminum oxidation. However, MA Al/PTFE did have a shorter total burn time. The PM of Al/PTFE powder had a shorter ignition delay than neat spherical aluminum due to the rapid decomposition of PTFE into reactive fluorocarbon compounds, but the subsequent fluorocarbon reactions also created a secondary luminosity profile that significantly increased the total burn time of the system. The explosive shock ignition of aluminum and aluminum-silicon eutectic alloy compacts was evaluated with and without polymer inclusions. A statistical analysis was completed, investigating the effects of: detonation train orientation (into or not into a hard surface); the high explosive driver; whether the metal/polymer system is mechanically activated; particle size; particle morphology

  1. Reverse and pseudo redistribution of thallium-201 in healed myocardial infarction and normal and negative thallium-201 washout in ischemia due to background oversubtraction

    SciTech Connect

    Lear, J.L.; Raff, U.; Jain, R.

    1988-09-15

    While the interpolative background subtraction used in quantitative planar thallium scanning can significantly overestimate the background overlying the heart, the effects of background oversubtraction on quantitative analysis have not been well defined. A mathematical model that relates myocardial washout determined using interpolative background subtraction to true myocardial washout is presented. The model was validated using phantoms and applied to myocardial and pulmonary thallium kinetic data in 100 patients, 85 with and 15 without coronary artery disease. The model showed that when using interpolative background subtraction, measured washout equals true washout in normally perfused myocardium; however, depending on the relation between myocardial and pulmonary thallium clearance, myocardial washout in ischemic regions and areas of infarction can be substantially over- or underestimated. Based on generally accepted quantitative criteria, this incorrect washout determination can at times lead to misdiagnosis of infarction as ischemia and ischemia as normally perfused tissue. It can also cause both ''reverse redistribution'' and ''pseudo redistribution'' of thallium in myocardial infarction in the absence of a physiologic basis.

  2. Illustrating a new approach to estimating potential reduction in fish species richness due to flow alteration on a global scale

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Yanagawa, A.; Khajuria, A.; Sui, P.; Iwasaki, Y.; Hirano, K.; Mahendran, R.; Koirala, S.; Hirabayashi, Y.; Yoshimura, C.; Kanae, S.

    2013-06-01

    Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystem. In order to globally assess the future status of freshwater ecosystem under regime shifts in river discharge, global-scale hydrological simulations need to be connected with a model to estimate the soundness of freshwater ecosystem. However, the explicit combination of those two on a global scale is still in its infancy. A couple of statistical models are introduced here to link flow regimes to fish species richness (FSR): one based on a linear relationship between FSR and mean river discharge, and the other based on a relationship between FSR and ecologically relevant flow indices involving other several flow characteristics as well as mean river discharge. The former one has been sometimes used in global simulation studies, but the latter one is newly introduced here in the context of global simulation. These statistical models for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of flow alterations due to climate change on FSR changes. Generally, future reductions in FSR by the latter method are larger and much more scattered rather than by the former method. In arid regions, both models provide reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reduction in FSR is different. On the other hand, large reductions in FSR only by the latter model are detected in heavy-snow regions due to the increases of mean discharge and frequency of low and high flows. Although we need further research to conclude which is more relevant, this study demonstrates that the new model could show a considerably different behavior in assessing the global impact of flow alteration on freshwater ecosystem change.

  3. Reduced Mitochondrial Function in Human Huntington Disease Lymphoblasts is Not Due to Alterations in Cardiolipin Metabolism or Mitochondrial Supercomplex Assembly.

    PubMed

    Mejia, Edgard M; Chau, Sarah; Sparagna, Genevieve C; Sipione, Simonetta; Hatch, Grant M

    2016-05-01

    Huntington's Disease (HD) is an autosomal dominant disease that occurs as a result of expansion of the trinucleotide repeat CAG (glutamine) on the HTT gene. HD patients exhibit various forms of mitochondrial dysfunction within neurons and peripheral tissues. Cardiolipin (Ptd2Gro) is a polyglycerophospholipid found exclusively in mitochondria and is important for maintaining mitochondrial function. We examined if altered Ptd2Gro metabolism was involved in the mitochondrial dysfunction associated with HD. Mitochondrial basal respiration, spare respiratory capacity, ATP coupling efficiency and rate of glycolysis were markedly diminished in Epstein-Barr virus transformed HD lymphoblasts compared to controls (CTRL). Mitochondrial supercomplex formation and Complex I activity within these supercomplexes did not vary between HD patients with different length of CAG repeats and appeared unaltered compared to CTRL. In contrast, in vitro Complex I enzyme activity in mitochondrial enriched samples was reduced in HD lymphoblasts compared to CTRL. The total cellular pool size of Ptd2Gro and its synthesis/remodeling from [(3)H]acetate/[(14)C]oleate were unaltered in HD lymphoblasts compared to CTRL. In addition, the molecular species of Ptd2Gro were essentially unaltered in HD lymphoblasts compared to CTRL. We conclude that compared to CTRL lymphoblasts, HD lymphoblasts display impaired mitochondrial basal respiration, spare respiratory capacity, ATP coupling efficiency and rate of glycolysis with any pathological CAG repeat length, but this is not due to alterations in Ptd2Gro metabolism. We suggest that HD patient lymphoblasts may be a useful model to study defective energy metabolism that does not involve alterations in Ptd2Gro metabolism. PMID:26846325

  4. Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration

    NASA Astrophysics Data System (ADS)

    Yoshikawa, S.; Yanagawa, A.; Iwasaki, Y.; Sui, P.; Koirala, S.; Hirano, K.; Khajuria, A.; Mahendran, R.; Hirabayashi, Y.; Yoshimura, C.; Kanae, S.

    2014-02-01

    Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of climate-change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although further research is clearly needed to conclude which method is more appropriate, this study demonstrates that the FSR-FLVAR method could produce considerably different results when assessing the global role of flow alterations in changing freshwater ecosystems.

  5. Modeling of the relationship between the environmental air pollution, clinical risk factors, and hospital mortality due to myocardial infarction in Isfahan, Iran

    PubMed Central

    Sadeghi, Mehraban; Ahmadi, Ali; Baradaran, Azar; Masoudipoor, Neda; Frouzandeh, Soleiman

    2015-01-01

    Background: This study aimed to determine the relationship between the environmental factor, clinical risk factors, and individual variables with mortality due to acute myocardial infarction (MI) in Isfahan. Materials and Methods: This cross-sectional study was performed between April 2012 and March 2013. The data on the patients’ mortality due to MI in Isfahan were obtained from the MI National Registry. The international classification system (ICD10: I21-I22) was used to diagnose MI. The air quality indicators and environmental variables were used to measure the air pollution. Multilevel logistic regression in the Stata software was used to determine the factors associated with mortality in patients and odds ratios (ORs) were calculated. Results: Six hundred eleven patients with MI were studied during 1-year. 444 (72.2%) patients were male and the rest were female. 4.7% of the patients died due to MI. The mean age at MI incidence was 62.2 ± 13 years. Of the air pollution parameters, PM10 had the maximum mean concentration (49.113 ppm), followed by NOX, NO, NO2, CO, SO2, and O3. The adjusted OR of mortality was derived 2.07 (95% CI: 1.5-2.85) for right bundle branch block, 1.5 (95% CI: 1.3-1.7) for ST-segment elevation MI, 1.84 (95% CI: 1.13-3) for age, 1.06 (95% CI: 1.01-1.20) for CO, 1.1 (95% CI: 1.03-1.30) for O3, and 1.04 (95% CI: 1.01-1.4) for SO2, all of which were considered as the risk factors of mortality. However, OR of mortality was 0.79 for precipitation (95% CI: 0.74-0.84) and 0.52 for angioplasty (95% CI: 0.4-0.68) were considered as protective factors of mortality. The individual characteristics including age, history of MI in the immediate family, hypertension, and diabetes were significantly associated with mortality from MI. The indices of air pollution including SO2, CO, O3, and environmental factors such as the precipitation and temperature were the determinants of mortality in patients with MI. Conclusion: With regards to the factors

  6. Proinflammatory and Th1 cytokine alterations following ultraviolet radiation enhancement of disease due to influenza infection in mice.

    PubMed

    Ryan, Lisa K; Copeland, Lisa R; Daniels, Mary J; Costa, Elisabeth R; Selgrade, Mary Jane K

    2002-05-01

    Exposure of rodents to immunosuppressive agents such as ozone, dioxin, or ultraviolet radiation (UVR) leads to increased morbidity and mortality following influenza virus infection. However, these adverse effects are not related to the suppression of virus-specific immune responses. Our laboratory showed that UVR increased the morbidity, mortality, and pathogenesis of influenza virus without affecting protective immunity to the virus, as measured by resistance to reinfection, suggesting that UVR and other immunosuppressive pollutants such as dioxin and ozone may exacerbate early responses that contribute to the pathogenesis of a primary viral infection. In the present study, we examined the mechanism of UVR-enhanced mortality in the absence of effects on virus-specific immunity and tested the hypothesis that modulation of cytokine levels was associated with increased deaths and body weight loss. BALB/c mice were exposed to 8.2 kJ/m(2) UVR and were infected 3 days later with a sublethal influenza virus infection (LD(40) of mouse-adapted Hong Kong influenza A/68, H(3)N(2)). Influx of inflammatory cells, proinflammatory cytokines, and cytokines produced by T-helper lymphocytes (Th1 and Th2) were measured in lung homogenates (LH) as well as in bronchoalveolar lavage fluid (BAL). UVR preexposure decreased the influenza-induced lymphocytic influx 5 days after infection, but did not alter macrophage and neutrophil influx into the lung, or increase virus titers significantly. Although interferon (IFN)-gamma, total interleukin (IL)-12, IL-6, and TNF-alpha were altered in mice that received UVR exposure prior to infection, no clear association was made that correlated with the UVR-induced increase in body weight loss and mortality due to influenza infection. PMID:11961220

  7. Sphingolipid Therapy in Myocardial Ischemia-Reperfusion Injury

    PubMed Central

    Gundewar, Susheel; Lefer, David J.

    2009-01-01

    Sphingolipids are known to play a significant physiological role in cell growth, cell differentiation, and critical signal transduction pathways. Recent studies have demonstrated a significant role of sphingolipids and their metabolites in the pathogenesis of myocardial ischemia-reperfusion injury. Our laboratory has investigated the cytoprotective effects of N,N,N-Trimethylsphingosine chloride (TMS), a stable N-methylated synthetic sphingolipid analogue on myocardial and hepatic ischemia reperfusion injury in clinically relevant in vivo murine models of ischemia-reperfusion injury. TMS administered intravenously at the onset of ischemia reduced myocardial infarct size in the wild-type and obese (ob/ob) mice. Following myocardial I/R, there was an improvement in cardiac function in the wild-type mice. Additionally, TMS also decreased serum liver enzymes following hepatic I/R in wild-type mice. The cytoprotective effects did not extend to the ob/ob mice following hepatic I/R or to the db/db mice following both myocardial and hepatic I/R. Our data suggests that although TMS is cytoprotective following I/R in normal animals, the cytoprotective actions of TMS are largely attenuated in obese and diabetic animals which may be due to altered signaling mechanisms in these animal models. Here we review the therapeutic role of TMS and other sphingolipids in the pathogenesis of myocardial ischemia reperfusion injury and their possible mechanisms of cardioprotection. PMID:17928150

  8. Hydrogeochemical alteration of groundwater due to a CO2 injection test into a shallow aquifer in Northeast Germany

    NASA Astrophysics Data System (ADS)

    Dethlefsen, Frank; Peter, Anita; Hornbruch, Götz; Lamert, Hendrik; Garbe-Schönberg, Dieter; Beyer, Matthias; Dietrich, Peter; Dahmke, Andreas

    2014-05-01

    The accidental release of CO2 into potable aquifers, for instance as a consequence of a leakage out of a CO2 store site, can endanger drinking water resources due to the induced geochemical processes. A 10-day CO2 injection experiment into a shallow aquifer was carried out in Wittstock (Northeast Germany) in order to investigate the geochemical impact of a CO2 influx into such an aquifer and to test different monitoring methods. Information regarding the site investigation, the injection procedure monitoring setup, and first geochemical monitoring results are described in [1]. Apart from the utilization of the test results to evaluate monitoring approaches [2], further findings are presented on the evaluation of the geophysical monitoring [3], and the monitoring of stable carbon isotopes [4]. This part of the study focuses of the hydrogeochemical alteration of groundwater due to the CO2 injection test. As a consequence of the CO2 injection, major cations were released, i.e. concentrations increased, whereas major anion concentrations - beside bicarbonate - decreased, probably due to increased anion sorption capacity at variably charged exchange sites of minerals. Trace element concentrations increased as well significantly, whereas the relative concentration increase was far larger than the relative concentration increase of major cations. Furthermore, geochemical reactions show significant spatial heterogeneity, i.e. some elements such as Cr, Cu, Pb either increased in concentration or remained at stable concentrations with increasing TIC at different wells. Statistical analyses of regression coefficients confirm the different spatial reaction patterns at different wells. Concentration time series at single wells give evidence, that the trace element release is pH dependent, i.e. trace elements such as Zn, Ni, Co are released at pH of around 6.2-6.6, whereas other trace elements like As, Cd, Cu are released at pH of 5.6-6.4. [1] Peter, A., et al., Investigation of

  9. A bypass case due to an acute inferior myocardial infarction caused by vascular occlusion of the left subclavian artery and left anterior descending artery.

    PubMed

    Altas, Yakup; Ulugg, Ali Veysel

    2016-01-01

    ST segment elevation is the most common electrocardiographic finding in acute myocardial infarction. ST elevation in chest leads generally represents left anterior descending artery occlusion, while elevation in DII and III, and aVF represents right coronary and circumflex artery occlusion. A female patient aged 66 years was admitted to our emergency service with ST elevation in leads DIII and aVF. A diagnosis of acute inferior myocardial infarction was made. The patient's history included coronary artery bypass graft involving the left internal mammary artery to the left anterior descending coronary artery and aorta to the right coronary artery. The patient was taken to the cardiac catheterization laboratory for primary percutaneous coronary intervention and a lesion in the left anterior descending artery was identified. Additionally, the left subclavian artery was totally occluded. Following intervention to the lesion, the patient was discharged on day 4 of admission. PMID:27555777

  10. A bypass case due to an acute inferior myocardial infarction caused by vascular occlusion of the left subclavian artery and left anterior descending artery

    PubMed Central

    Altas, Yakup; Ulugg, Ali Veysel

    2016-01-01

    ST segment elevation is the most common electrocardiographic finding in acute myocardial infarction. ST elevation in chest leads generally represents left anterior descending artery occlusion, while elevation in DII and III, and aVF represents right coronary and circumflex artery occlusion. A female patient aged 66 years was admitted to our emergency service with ST elevation in leads DIII and aVF. A diagnosis of acute inferior myocardial infarction was made. The patient’s history included coronary artery bypass graft involving the left internal mammary artery to the left anterior descending coronary artery and aorta to the right coronary artery. The patient was taken to the cardiac catheterization laboratory for primary percutaneous coronary intervention and a lesion in the left anterior descending artery was identified. Additionally, the left subclavian artery was totally occluded. Following intervention to the lesion, the patient was discharged on day 4 of admission. PMID:27555777

  11. Fetal rat metabonome alteration by prenatal caffeine ingestion probably due to the increased circulatory glucocorticoid level and altered peripheral glucose and lipid metabolic pathways

    SciTech Connect

    Liu, Yansong; Xu, Dan; Feng, Jianghua; Kou, Hao; Liang, Gai; Yu, Hong; He, Xiaohua; Zhang, Baifang; Chen, Liaobin; Magdalou, Jacques; Wang, Hui

    2012-07-15

    The aims of this study were to clarify the metabonome alteration in fetal rats after prenatal caffeine ingestion and to explore the underlying mechanism pertaining to the increased fetal circulatory glucocorticoid (GC). Pregnant Wistar rats were daily intragastrically administered with different doses of caffeine (0, 20, 60 and 180 mg/kg) from gestational days (GD) 11 to 20. Metabonome of fetal plasma and amniotic fluid on GD20 were analyzed by {sup 1}H nuclear magnetic resonance-based metabonomics. Gene and protein expressions involved in the GC metabolism, glucose and lipid metabolic pathways in fetal liver and gastrocnemius were measured by real-time RT-PCR and immunohistochemistry. Fetal plasma metabonome were significantly altered by caffeine, which presents as the elevated α- and β‐glucose, reduced multiple lipid contents, varied apolipoprotein contents and increased levels of a number of amino acids. The metabonome of amniotic fluids showed a similar change as that in fetal plasma. Furthermore, the expressions of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD-2) were decreased, while the level of blood GC and the expressions of 11β-HSD-1 and glucocorticoid receptor (GR) were increased in fetal liver and gastrocnemius. Meanwhile, the expressions of insulin-like growth factor 1 (IGF-1), IGF-1 receptor and insulin receptor were decreased, while the expressions of adiponectin receptor 2, leptin receptors and AMP-activated protein kinase α2 were increased after caffeine treatment. Prenatal caffeine ingestion characteristically change the fetal metabonome, which is probably attributed to the alterations of glucose and lipid metabolic pathways induced by increased circulatory GC, activated GC metabolism and enhanced GR expression in peripheral metabolic tissues. -- Highlights: ► Prenatal caffeine ingestion altered the metabonome of IUGR fetal rats. ► Caffeine altered the glucose and lipid metabolic pathways of IUGR fetal rats. ► Prenatal caffeine

  12. Time-Course of Alterations in Myocardial Glucose Utilization in the Zucker Diabetic Fatty (ZDF) Rat with Correlation to Gene Expression of Glucose Transporters: A Small Animal PET Investigation

    PubMed Central

    Shoghi, Kooresh I.; Gropler, Robert J.; Sharp, Terry; Herrero, Pilar; Fettig, Nicole; Su, Yi; Mitra, Mayurranjan S.; Kovacs, Attila; Finck, Brian N.; Welch, Michael J.

    2010-01-01

    Objective Diabetic cardiomyopathy is associated with abnormalities in glucose metabolism. We evaluated myocardial glucose metabolism in a rodent model of Type 2 Diabetes (T2D), namely the Zucker Diabetic Rat (ZDF), and validated PET measures of glucose uptake against gene and protein expression of glucose transporters. Methods Six lean and ZDF rat underwent small animal PET imaging at the age of 14 weeks and at the age of 19 weeks. The imaging protocol consisted of a 60-minute dynamic acquisition with 18FDG (0.5–0.8mCi). Dynamic images were reconstructed using filtered back projection (FBP) with a 2.5 zoom on the heart and 40 frames per imaging session. PET measures of myocardial glucose uptake rate (MGUp) and utilization were determined with an input function derived by the Hybrid Image- Blood Sampling (HIBS) algorithm on recovery-corrected anterolateral myocardial regions of interest. Following the PET imaging session at week 19, hearts were extracted for gene and protein expression analysis of GLUT1 and GLUT4. The dependence of MGUp on gene expression of GLUT1 and GLUT4 was characterized by multiple-regression analysis. Results Compared to lean littermate control rats, MGUp was significantly depressed in ZDF rats at both week 14 and week 19 (P<0.006). Moreover, lean rats at week 19 displayed significantly higher MGUp than week 14 (P=0.007). Consistent with diminished MGUp, gene expression of GLUT4 was significantly (P=0.004) lower in ZDF rats. Finally, MGUp significantly (P=0.0003) correlated with gene expression of GLUT4. Conclusions Using small animal PET, we confirmed alterations in myocardial glucose utilization and validated PET measure of MGUp against gene and protein expression of glucose transporters in the diabetic heart of an animal model of T2D. PMID:18632819

  13. Declines in Soil pH due to Anthropogenic Nitrogen Inputs Alter Buffering and Exchange Reactions in Tropical Forest Soils

    NASA Astrophysics Data System (ADS)

    Lohse, K. A.

    2003-12-01

    Anthropogenic nitrogen (N) inputs may alter tropical soil buffering and exchange reactions that have important implications for nutrient cycling, forest productivity, and downstream ecosystems. In contrast to relatively young temperate soils that are typically buffered from N inputs by base cation reactions, aluminum reactions may serve to buffer highly weathered tropical soils and result in immediate increases in aluminum mobility and toxicity. Increased nitrate losses due to chronic N inputs may also deplete residual base cations in already weathered base cation-poor soils, further acidify soils, and thereby reduce nitrate mobility through pH-dependent anion exchange reactions. To test these hypotheses, I determined soil pH and cation and anion exchange capacity (CEC and AEC) and measured base cation and aluminum soil solution losses following first-time and long-term experimental N additions from two Hawaiian tropical forest soils, a 300 year old Andisol and a 4.1 million year old Oxisol. I found that elevated base cation losses accompanied increased nitrate losses after first time N additions to the young Andisol whereas immediate and large aluminum losses were associated with increased nitrate losses from the Oxisol. In the long-term, base cation and aluminum losses increased in proportion to nitrate losses. Long-term N additions at both sites resulted in significant declines in soil pH, decreased CEC and increased AEC. These results suggest that even chronic N inputs resulting in small but elevated nitrate losses may deplete residual base cations, increase mobility and toxicity of aluminum, and potentially lead to declines in forest productivity and acidification of downstream ecosystems. These findings also suggest that AEC may provide a long-term mechanism to delay nitrate losses in tropical forests with significant variable charge that are experiencing chronic anthropogenic N inputs.

  14. Reduced ability to release adenosine by diabetic rat cardiac fibroblasts due to altered expression of nucleoside transporters

    PubMed Central

    Podgorska, Marzena; Kocbuch, Katarzyna; Grden, Marzena; Szutowicz, Andrzej; Pawelczyk, Tadeusz

    2006-01-01

    Adenosine produced by cardiac cells is known to attenuate the proliferation of cardiac fibroblasts (CFs), inhibit collagen synthesis, and protect the myocardium against ischaemic and reperfusion injury. Diabetic patients' hearts exhibit ventricular hypertrophy and demonstrate reduced tolerance to hypoxia or ischaemia. In this study, we characterize the effects of glucose and insulin on processes that determine the release of adenosine from CFs. We showed that during ATP depletion, rat CFs cultured in the absence of insulin release significantly less adenosine compared to cells grown in the presence of insulin. Moreover, under both conditions the quantity of released adenosine depends on glucose concentration. We demonstrate that this is due to altered expression of nucleoside transporters. High glucose (25 mm) induced 85% decrease in nucleoside transporter ENT1 mRNA levels. Decrease of the insulin level below 10−11m resulted in over 3-fold increase in the nucleoside transporter CNT2 mRNA content. Measurements of adenosine transport in CFs cultured in the presence of 5 mm glucose and 10 nm insulin showed that the bidirectional equilibrative adenosine transport accounted for 70% of the overall adenosine uptake. However, cells grown in the presence of high glucose (25 mm) demonstrated 65% decrease of the bidirectional equilibrative adenosine transport. Experiments on CFs cultured in the absence of insulin showed that the unidirectional Na+-dependent adenosine uptake rose in these cells more than 4-fold. These results indicate that the development of diabetes may result in an increased uptake of interstitial adenosine by CFs, and reduction of the ability of these cells to release adenosine during ATP deprivation. PMID:16873415

  15. Alteration of the Carbon and Nitrogen Isotopic Composition in the Martian Surface Rocks Due to Cosmic Ray Exposure

    NASA Technical Reports Server (NTRS)

    Pavlov, A. A.; Pavlov, A. K.; Ostryakov, V. M.; Vasilyev, G. I.; Mahaffy, P.; Steele, A.

    2014-01-01

    C-13/C-12 and N-15/N-14 isotopic ratios are pivotal for our understanding of the Martian carbon cycle, history of the Martian atmospheric escape, and origin of the organic compounds on Mars. Here we demonstrate that the carbon and nitrogen isotopic composition of the surface rocks on Mars can be significantly altered by the continuous exposure of Martian surface to cosmic rays. Cosmic rays can effectively produce C-13 and N-15 isotopes via spallation nuclear reactions on oxygen atoms in various Martian rocks. We calculate that in the top meter of the Martian rocks, the rates of production of both C-13 and N-15 due to galactic cosmic rays (GCRs) exposure can vary within 1.5-6 atoms/cm3/s depending on rocks' depth and chemical composition. We also find that the average solar cosmic rays can produce carbon and nitrogen isotopes at a rate comparable to GCRs in the top 5-10 cm of the Martian rocks. We demonstrate that if the total carbon content in a surface Martian rock is <10 ppm, then the "light," potentially "biological" C-13/C-12 ratio would be effectively erased by cosmic rays over 3.5 billion years of exposure. We found that for the rocks with relatively short exposure ages (e.g., 100 million years), cosmogenic changes in N-15/N-14 ratio are still very significant. We also show that a short exposure to cosmic rays of Allan Hills 84001 while on Mars can explain its high-temperature heavy nitrogen isotopic composition (N-15/N-14). Applications to Martian meteorites and the current Mars Science Laboratory mission are discussed.

  16. Illustrating a New Global-scale Approach to Estimating Potential Reduction in Fish Species Richness due to Flow Alteration

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Sayaka; Yanagawa, Aki; Iwasaki, Yuichi; Sui, Pengzhe; Koirala, Sujan; Khajuria, Anupam; Hirano, Kazunari; Mahendran, Roobavannan; Hirabayashi, Yukiko; Yoshimura, Chihiro; Kanae, Shinjiro

    2014-05-01

    Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of state-of-art global river discharge simulations using latest outputs of 11 coupled atmosphere-ocean general circulation models to evaluate the potential impact of climate- change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than those with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease in the future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although we cannot determine only by this study which this prediction is more reliable, it can be argued that efforts to take plural ecologically relevant flow indices into account would lead to more appropriate methods for

  17. Myocardial Tissue Doppler Velocity in Child Growth

    PubMed Central

    Choi, Sun-Ha; Kim, Nam Kyun; Jung, Jo Won; Choi, Jae Young

    2016-01-01

    Background In adults, tissue Doppler imaging (TDI) is a recommended component of routine echocardiography. However, TDI velocities are less accepted in pediatrics, due to their strong variability and age dependence in children. This study examines the distribution of myocardial tissue Doppler velocities in healthy children to assess the effect of age with cardiac growth on the various echocardiographic measurements. Methods Total 144 healthy children were enrolled in this study. They were recruited from the pediatric outpatient clinic for routine well-child visits. The statistical relationships between age and TDI values were analyzed. Also, the statistical relationships between body surface area (BSA) and TDI values, left ventricle end-diastolic dimension (LVEDD) and TDI values were analyzed. Also, we conducted multivariate analysis of cardiac growth parameters such as, age, BSA, LVEDD and TDI velocity data. Results All of the age, BSA, and LVEDD had positive correlations with deceleration time (DT), pressure half-time (PHT), peak early diastolic myocardial velocity, peak systolic myocardial velocity, and had negative correlations with peak late diastolic velocity (A) and the ratio of trans-mitral inflow velocity to early diastolic velocity of mitral annulus (E/E'). In the multivariate analysis, all of the age, BSA, and LVEDD had positive correlations with DT, PHT, and negative correlations with A and E/E'. Conclusion The cardiac growth parameters related alterations of E/E' may suggest that diastolic myocardial velocities are cardiac growth dependent, and diastolic function has positive correlation with cardiac growth in pediatric group. This cardiac growth related myocardial functional variation would be important for assessment of cardiac involvement either in healthy and sick child. PMID:27081443

  18. A Coupled Biosphere-Atmosphere Climate Model Suitable for Studies of Climatic Change Due to Land Surface Alterations.

    NASA Astrophysics Data System (ADS)

    Varejão-Silva, Mário Adelmo; Franchito, Sergio H.; Brahmananda Rao, Vadlamudi

    1998-07-01

    A biosphere model based on BATS (Biosphere-Atmosphere Transfer Scheme) is coupled to a primitive equation global statistical-dynamical model in order to study the climatic impact due to land surface alterations. The fraction of the earth's surface covered by each vegetation type according to BATS is obtained for each latitude belt. In the control experiment, the mean annual zonally averaged climate is well simulated when compared with observations. Deforestation and desertification experiments are performed. In the deforestation experiment, the evergreen broadleaf tree in the Amazonian region is substituted by short grass; in the desertification experiment the semidesert, and the tall grass and deciduous shrubs are substituted by desert and semidesert in the African continent, respectively.The results show that in both the experiments there is a reduction in evapotranspiration and precipitation in the perturbed region and an increase in the soil surface temperature, the temperature of the foliage air layer, and the foliage temperature. Also, the latent heat flux decreased in the perturbed cases relative to the control case. To partially compensate for the decrease in latent heating, sensible heat flux increased in the perturbed cases compared with the control case. The changes in the deforestation case are greater in the latitude belt centered at 5°S, where in most part the Amazonian forest is situated. Otherwise, the changes in the desertification are greater in the latitude belt centered at 15°N. When there is also degradation of the African tropical forest (substitution of evergreen broadleaf trees by short grass), the greatest changes occur southward from that region (in the latitude belt centered at 5°N), and the magnitude of the changes are also increased. This shows the important role of the modification of tropical forest when there is degradation of the vegetation in the African region from 20°N to 0°°.The results regarding the changes in the

  19. Myocardial diseases of animals.

    PubMed Central

    Van Vleet, J. F.; Ferrans, V. J.

    1986-01-01

    In this review we have attempted a comprehensive compilation of the cardiac morphologic changes that occur in spontaneous and experimental myocardial diseases of animals. Our coverage addresses diseases of mammals and birds and includes these diseases found in both domesticated and wild animals. A similar review of the myocardial diseases in this broad range of animal species has not been attempted previously. We have summarized and illustrated the gross, microscopic, and ultrastructural alterations for these myocardial diseases; and, whenever possible, we have reviewed their biochemical pathogenesis. We have arranged the myocardial diseases for presentation and discussion according to an etiologic classification with seven categories. These include a group of idiopathic or primary cardiomyopathies recognized in man (hypertrophic, dilated, and restrictive types) and a large group of secondary cardiomyopathies with known causes, such as inherited tendency; nutritional deficiency; toxicity; physical injury and shock; endocrine disorders, and myocarditides of viral, bacterial, and protozoal causation. Considerable overlap exists between each of the etiologic groups in the spectrum of pathologic alterations seen in the myocardium. These include various degenerative changes, myocyte necrosis, and inflammatory lesions. However, some diseases show rather characteristic myocardial alterations such as vacuolar degeneration in anthracycline cardiotoxicity, myofibrillar lysis in furazolidone cardiotoxicity, calcification in calcinosis of mice, glycogen accumulation in the glycogenoses, lipofuscinosis in cattle, fatty degeneration in erucic acid cardiotoxicity, myofiber disarray in hypertrophic cardiomyopathy, and lymphocytic inflammation with inclusion bodies in canine parvoviral myocarditis. The myocardial diseases represent the largest group in the spectrum of spontaneous cardiac diseases of animals. Pericardial and endocardial diseases and congential cardiac diseases are

  20. The altered expression profile of microRNAs in cardiopulmonary bypass canine models and the effects of mir-499 on myocardial ischemic reperfusion injury

    PubMed Central

    2013-01-01

    Background MicroRNAs were enrolled in various cardiovascular disease especially ischemic heart diseases, but the microRNA changes during myocardial ischemia reperfusion injury underwent cardiopulmonary bypass are still unknown. This study screens the microRNA differences in CPB canines and evaluates the relationship of microRNAs with myocardial ischemia reperfusion injury. Methods 13 healthy canines received CPB with 60 minutes of aortic clamping and cardioplegic arrest, followed by 90 minutes reperfusion. Left ventricular myocardial samples, blood samples and hemodynamic data were taken at different time points. We performed microRNAs microarray experiments upon the left ventricle myocardium tissue of canines before CPB and after reperfusion for 90 minutes by pooling 3 tissue samples together and used qRT-PCR for confirmation. Results Statistically significant difference was found in mir-499 level before CPB and after reperfusion (T1 vs. T4, p = 0.041). We further examined the mir-499 levels by using qRT-PCR in all 13 canines at 4 different time points (T1 vs. T4, p = 0.029). Mir-499 expression was negatively correlated with cardiac troponin T (cTnT) and creatine kinase- MB (CK-MB) levels of canines in all time points samples (r = 0.469, p < 0.001 and r = 0.273, p = 0.050 respectively). Moreover, higher mir-499 expression level was associated with higher dP/dtmax at 25 minutes and 90 minutes after reperfusion. Conclusion Myocardial ischemic reperfusion injury with cardiopulmonary bypass results in declining level of mir-499 expression in left ventricle myocardium of canines, suggesting mir-499 would be a potential therapeutic target in cardiac protection during open heart surgery. PMID:23800236

  1. Myocardial Bridge

    MedlinePlus

    ... artery. See also on this site: Ask a Texas Heart Institute Doctor: Search "myocardial bridge" Updated August ... comments. Terms of Use and Privacy Policy © Copyright Texas Heart Institute All rights reserved.

  2. Myocardial ischemia due to a type IV dual LAD with the long LAD arising from the right sinus of valsalva: a case report and literature review.

    PubMed

    Gao, Xiangyu; Li, Hongwei; Chen, Hui

    2015-01-01

    We herein report the case of a 60-year-old man who presented with chest discomfort. Coronary angiography demonstrated that the short left anterior descending artery (LAD) arose from the left main coronary artery and the long LAD from the right coronary sinus of Valsalva, which was confirmed by 64-slice multidetector computed tomography coronary angiography. Single-photon emission computed tomography revealed a significant, almost irreversible degree of hypoperfusion in the anterior wall of the left ventricle, thus indicating that the short LAD was associated with myocardial ischemia and severe atherosclerotic lesions. Therefore, SPECT showed that the myocardium was largely necrotic, and we did not perform angioplasty for the short LAD. PMID:26466699

  3. Myocardial infarction resulting from coronary artery dissection in an adolescent with Ehlers-Danlos syndrome type IV due to a type III collagen mutation.

    PubMed Central

    Adès, L. C.; Waltham, R. D.; Chiodo, A. A.; Bateman, J. F.

    1995-01-01

    Ehlers-Danlos syndrome encompasses a group of inherited disorders of connective tissue, some of which are characterised by abnormalities of collagen metabolism. The chromosomal location, identified genes and biochemical defects, inheritance pattern, and clinical features for the various known subtypes are outlined. Prenatal diagnosis is possible for types IV, VI, VIIA1, and VIIA2. An unusual presentation of type IV Ehlers-Danlos syndrome in a 16 year old boy with an anterior myocardial infarction resulting from dissection of the left anterior descending coronary artery is reported here. A clinical diagnosis of type IV Ehlers-Danlos syndrome was made subsequently and confirmed by the reduced production, impaired secretion, and abnormally slow electrophoretic migration of type III collagen, indicating an underlying mutation in the COL3A1 gene. This patient represents the first case of type IV Ehlers-Danlos syndrome with symptomatic coronary artery dissection. Images PMID:7546986

  4. Blastocyst implantation failure in mice due to "nonreceptive endometrium": endometrial alterations by Hibiscus rosa-sinensis leaf extract.

    PubMed

    Nivsarkar, Manish; Patel, Manoj; Padh, Harish; Bapu, Cherian; Shrivastava, Neeta

    2005-03-01

    Many plants are known to possess antifertility activity. However, limited attempts have been made to scientifically evaluate these claims. Hibiscus rosa-sinensis flowers have been shown to possess antifertility and abortifacient activity. In this report, antiimplantation activity of water extract of leaves of H. rosa-sinensis was investigated. Pregnant female mice were dosed with extract (100 mg/kg body weight) from days 1 to 6 of pregnancy. No implantation sites were observed in treated animals when they were surgically opened on day 15 of pregnancy. Biochemical and biophysical alterations were observed in the endometrium in treated animals, especially on day 5, at 4:40 a.m., the day of implantation. A sharp increase in superoxide anion radical and a sharp fall in superoxide dismutase (SOD) activity, as seen in the endometrium from control animals, were altered in treated animals. The extract also exhibited antiestrogenic activity, as judged by increase in uterine weight. The physiological alterations induced by water extract of H. rosa-sinensis are discussed. PMID:15722074

  5. Bentonite alteration due to thermal-hydro-chemical processes during the early thermal period in a nuclear waste repository

    SciTech Connect

    Xu, T.; Senger, R.; Finsterle, S.

    2011-02-01

    After closure of an underground nuclear waste repository, the decay of radionuclides will raise temperature in the repository, and the bentonite buffer will resaturate by water inflow from the surrounding host rock. The perturbations from these thermal and hydrological processes are expected to dissipate within hundreds to a few thousand years. Here, we investigate coupled thermal-hydro-chemical processes and their effects on the short-term performance of a potential nuclear waste repository located in a clay formation. Using a simplified geometric configuration and abstracted hydraulic parameters of the clayey formation, we examine geochemical processes, coupled with thermo-hydrologic phenomena, and potential changes in porosity near the waste container during the early thermal period. The developed models were used for evaluating the mineral alterations and potential changes in porosity of the buffer, which can affect the repository performance. The results indicate that mineral alteration and associated changes in porosity induced by early thermal and hydrological processes are relatively small and are expected to not significantly affect flow and transport properties. Chlorite precipitation was obtained in all simulation cases. A maximum of one percent volume fraction of chlorite could be formed, whose process may reduce swelling and sorption capacity of bentonite clay, affecting the performance of the repository. llitisation process was not obtained from the present simulations.

  6. Altered joint tribology in osteoarthritis: Reduced lubricin synthesis due to the inflammatory process. New horizons for therapeutic approaches.

    PubMed

    Szychlinska, M A; Leonardi, R; Al-Qahtani, M; Mobasheri, A; Musumeci, G

    2016-06-01

    Osteoarthritis (OA) is the most common form of joint disease. This review aimed to consolidate the current evidence that implicates the inflammatory process in the attenuation of synovial lubrication and joint tissue homeostasis in OA. Moreover, with these findings, we propose some evidence for novel therapeutic strategies for preventing and/or treating this complex disorder. The studies reviewed support that inflammatory mediators participate in the onset and progression of OA after joint injury. The flow of pro-inflammatory cytokines following an acute injury seems to be directly associated with altered lubricating ability in the joint tissue. The latter is associated with reduced level of lubricin, one of the major joint lubricants. Future research should focus on the development of new therapies that attenuate the inflammatory process and restore lubricin synthesis and function. This approach could support joint tribology and synovial lubrication leading to improved joint function and pain relief. PMID:27118399

  7. Alterations in the coupling functions between cortical and cardio-respiratory oscillations due to anaesthesia with propofol and sevoflurane.

    PubMed

    Stankovski, Tomislav; Petkoski, Spase; Raeder, Johan; Smith, Andrew F; McClintock, Peter V E; Stefanovska, Aneta

    2016-05-13

    The precise mechanisms underlying general anaesthesia pose important and still open questions. To address them, we have studied anaesthesia induced by the widely used (intravenous) propofol and (inhalational) sevoflurane anaesthetics, computing cross-frequency coupling functions between neuronal, cardiac and respiratory oscillations in order to determine their mutual interactions. The phase domain coupling function reveals the form of the function defining the mechanism of an interaction, as well as its coupling strength. Using a method based on dynamical Bayesian inference, we have thus identified and analysed the coupling functions for six relationships. By quantitative assessment of the forms and strengths of the couplings, we have revealed how these relationships are altered by anaesthesia, also showing that some of them are differently affected by propofol and sevoflurane. These findings, together with the novel coupling function analysis, offer a new direction in the assessment of general anaesthesia and neurophysiological interactions, in general. PMID:27045000

  8. Alterations in the coupling functions between cortical and cardio-respiratory oscillations due to anaesthesia with propofol and sevoflurane

    PubMed Central

    Petkoski, Spase; Raeder, Johan; Smith, Andrew F.; McClintock, Peter V. E.; Stefanovska, Aneta

    2016-01-01

    The precise mechanisms underlying general anaesthesia pose important and still open questions. To address them, we have studied anaesthesia induced by the widely used (intravenous) propofol and (inhalational) sevoflurane anaesthetics, computing cross-frequency coupling functions between neuronal, cardiac and respiratory oscillations in order to determine their mutual interactions. The phase domain coupling function reveals the form of the function defining the mechanism of an interaction, as well as its coupling strength. Using a method based on dynamical Bayesian inference, we have thus identified and analysed the coupling functions for six relationships. By quantitative assessment of the forms and strengths of the couplings, we have revealed how these relationships are altered by anaesthesia, also showing that some of them are differently affected by propofol and sevoflurane. These findings, together with the novel coupling function analysis, offer a new direction in the assessment of general anaesthesia and neurophysiological interactions, in general. PMID:27045000

  9. Wave Propagation of Myocardial Stretch: Correlation with Myocardial Stiffness

    PubMed Central

    Pislaru, Cristina; Pellikka, Patricia A.; Pislaru, Sorin V.

    2015-01-01

    The mechanism of flow propagation during diastole in the left ventricle (LV) has been well described. Little is known about the associated waves propagating along the heart wall s. These waves may have a mechanism similar to pulse wave propagation in arteries. The major goal of the study was to evaluate the effect of myocardial stiffness and preload on this wave transmission. Methods Longitudinal late diastolic deformation and wave speed (Vp) of myocardial stretch in the anterior LV wall were measured using sonomicrometry in sixteen pigs. Animals with normal and altered myocardial stiffness (acute myocardial infarction) were studied with and without preload alterations. Elastic modulus estimated from Vp (EVP; Moens-Korteweg equation) was compared to incremental elastic modulus obtained from exponential end -diastolic stress-strain relation (ESS). Myocardial distensibility and α-and β-coefficients of stress-strain relations were calculated. Results Vp was higher at reperfusion compared to baseline (2.6±1.3 m/s vs. 1.3±0.4 m/s; p=0.005) and best correlated with ESS (r 2=0.80, p<0.0001), β-coefficient (r2=0.78, p<0.0001), distensibility (r2=0.47, p=0.005), and wall thickness/diameter ratio (r2=0.42, p=0.009). Elastic moduli (EVP and ESS) were strongly correlated (r2=0.83, p<0.0001). Increasing preload increased Vp and EVP and decreased distensibility. At multivariate analysis, ESS, wall thickness, and end-diastolic and systolic LV pressures were independent predictors of Vp (r2model=0.83, p<0.0001). Conclusions The main determinants of wave propagation of longitudinal myocardial stretch were myocardial stiffness and LV geometry and pressure. This local wave speed could potentially be measured noninvasively by echocardiography. PMID:25193091

  10. Altered Hematopoiesis in Mice Lacking DNA Polymerase μ Is Due to Inefficient Double-Strand Break Repair

    PubMed Central

    Lucas, Daniel; Escudero, Beatriz; Ligos, José Manuel; Segovia, Jose Carlos; Estrada, Juan Camilo; Terrados, Gloria; Blanco, Luis; Samper, Enrique; Bernad, Antonio

    2009-01-01

    Polymerase mu (Polμ) is an error-prone, DNA-directed DNA polymerase that participates in non-homologous end-joining (NHEJ) repair. In vivo, Polμ deficiency results in impaired Vκ-Jκ recombination and altered somatic hypermutation and centroblast development. In Polμ−/− mice, hematopoietic development was defective in several peripheral and bone marrow (BM) cell populations, with about a 40% decrease in BM cell number that affected several hematopoietic lineages. Hematopoietic progenitors were reduced both in number and in expansion potential. The observed phenotype correlates with a reduced efficiency in DNA double-strand break (DSB) repair in hematopoietic tissue. Whole-body γ-irradiation revealed that Polμ also plays a role in DSB repair in non-hematopoietic tissues. Our results show that Polμ function is required for physiological hematopoietic development with an important role in maintaining early progenitor cell homeostasis and genetic stability in hematopoietic and non-hematopoietic tissues. PMID:19229323

  11. Metabolic alterations due to caloric restriction and every other day feeding in normal and growth hormone receptor knockout mice.

    PubMed

    Westbrook, Reyhan; Bonkowski, Michael S; Arum, Oge; Strader, April D; Bartke, Andrzej

    2014-01-01

    Mutations causing decreased somatotrophic signaling are known to increase insulin sensitivity and extend life span in mammals. Caloric restriction and every other day (EOD) dietary regimens are associated with similar improvements to insulin signaling and longevity in normal mice; however, these interventions fail to increase insulin sensitivity or life span in growth hormone receptor knockout (GHRKO) mice. To investigate the interactions of the GHRKO mutation with caloric restriction and EOD dietary interventions, we measured changes in the metabolic parameters oxygen consumption (VO2) and respiratory quotient produced by either long-term caloric restriction or EOD in male GHRKO and normal mice. GHRKO mice had increased VO2, which was unaltered by diet. In normal mice, EOD diet caused a significant reduction in VO2 compared with ad libitum (AL) mice during fed and fasted conditions. In normal mice, caloric restriction increased both the range of VO2 and the difference in minimum VO2 between fed and fasted states, whereas EOD diet caused a relatively static VO2 pattern under fed and fasted states. No diet significantly altered the range of VO2 of GHRKO mice under fed conditions. This provides further evidence that longevity-conferring diets cause major metabolic changes in normal mice, but not in GHRKO mice. PMID:23833202

  12. Geomorphic Framework to assess changes to aquatic habitat due to flow regulation and channel and floodplain alteration, Cedar River, Washington

    USGS Publications Warehouse

    Gendaszek, Andrew S.; Magirl, Christopher S.; Czuba, Christiana R.; Konrad, Christopher P.; Little, Rand

    2010-01-01

    Flow regulation, bank armoring, and floodplain alteration since the early 20th century have contributed to significant changes in the hydrologic regime and geomorphic processes of the Cedar River in Washington State. The Cedar River originates in the Cascade Range, provides drinking water to the Seattle metropolitan area, and supports several populations of anadromous salmonids. Flow regulation currently has limited influence on the magnitude, duration, and timing of high-flow events, which affect the incubation of salmonids as well as the production and maintenance of their habitat. Unlike structural changes to the channel and floodplain, flow regulation may be modified in the short-term to improve the viability of salmon populations. An understanding of the effects of flow regulation on those populations must be discerned over a range of scales from individual floods that affect the size of individual year classes to decadal high flow regime that influences the amount and quality of channel and off-channel habitat available for spawning and rearing. We present estimates of reach-scale sediment budgets and changes to channel morphology derived from historical orthoimagery, specific gage analyses at four long-term streamflow-gaging stations to quantify trends in aggradation, and hydrologic statistics of the magnitude and duration of peak streamflows. These data suggest a gradient of channel types from unconfined, sediment-rich segments to confined, sediment-poor segments that are likely to have distinct responses to high flows. Particle-size distribution data and longitudinal water surface and streambed profiles for the 56 km downstream of Chester Morse Lake measured in 2010 show the spatial extent of preferred salmonid habitat along the Cedar River. These historical and current data constitute a geomorphic framework to help assess different river management scenarios for salmonid habitat and population viability. PDF version of a presentation on changes to aquatic

  13. Cardiac and aortic structural alterations due to surgically-induced menopause associated with renovascular hypertension in rats.

    PubMed

    Mendonça, Leonardo de Souza; Fernandes-Santos, Caroline; Mandarim-de-Lacerda, Carlos Alberto

    2007-08-01

    Menopause and hypertension independently alter cardiovascular remodelling, but little is known about their effect on left ventricular and aortic wall remodelling. Eight-weeks-old Wistar rats were divided into four groups of six animals each: Sham group, OVX group (ovariectomized rats), 2K1C (two-kidneys, one-clip rats) and OVX + 2K1C group and kept until 19 weeks. Blood pressure (BP) increased 12% in OVX group, 35% in 2K1C and OVX + 2K1C groups compared with sham group. Vaginal cytology showed Sham and 2K1C rats cycling normally, whereas OVX and OVX + 2K1C rats were persistently in dioestrus or proestrus. At euthanasia, left ventricle (LV) and thoracic aorta were removed and analysed (immunohistochemistry and stereology). LV mass/tibia length ratio and cross-sectional area of cardiomyocytes increased in all groups except Sham. The intramyocardial vascularization reduced 30% in comparison with Sham group, with no difference among OVX, 2K1C and OVX + 2K1C groups. The cardiac interstitium increased more than 45% in both 2K1C and OVX + 2K1C groups compared with Sham, but there was no significant difference between Sham and OVX groups. Nuclei number of LV cardiomyocyte diminished in OVX group, followed by 2K1C group and OVX + 2K1C group, with no difference between the 2K1C and the OVX + 2K1C groups. There was positive immunostaining for angiotensin II AT1 receptor in smooth muscle cell layer of aortic tunica media in all groups. These results show that both ovariectomy and renovascular hypertension enhance BP as a single stimulus and therefore produce adverse cardiac remodelling. However, renovascular hypertension exerts a far greater influence than surgically-induced menopause in this parameter. PMID:17696911

  14. A higher aspect ratio enhanced bioaccumulation and altered immune responses due to intravenously-injected aluminum oxide nanoparticles.

    PubMed

    Park, Eun-Jung; Kim, Soo Nam; Kang, Min-Sung; Lee, Byoung-Seok; Yoon, Cheolho; Jeong, Uiseok; Kim, Younghun; Lee, Gwang-Hee; Kim, Dong-Wan; Kim, Jong Sung

    2016-07-01

    Aluminum oxide nanoparticles (AlO NP) have been widely utilized in a variety of areas, including in the optical, biomedical and electronic fields and in the overall development of nanotechnologies. However, their toxicological profiles are still not fully developed. This study compared the distribution and immunotoxicity of two rod-types of AlO NP. As reported previously, the two types of AlO NP had different aspect ratios (long-type: 6.2 ± 0.6, short-type: 2.1 ± 0.4), but the size and surface charge were very similar. On Day 14 after a single intravenous (IV) injection (1.25 or 5 mg/kg), both AlO NP accumulated primarily in the liver and spleen and altered the levels of redox response-related elements. The accumulated level was higher in mice exposed to the long-type AlO NP compared to the short-type. Additionally, it was noted that the levels of IL-1β, IL-8 and MCP-1 were enhanced in the blood of mice exposed to both types of AlO NP and the percentages of neutrophils and monocytes among all white blood cells were increased only in mice injected with the long-type AlO NP (5 mg/kg). In addition, as compared to the control, co-expression of CD80 and CD86 (necessary for antigen presentation) on splenocytes together with a decreased expression of chemotaxis-related marker (CD195) was attenuated by exposure to the AlO NP, especially the long-type. Taken together, the data suggest that accumulation following a single IV injection with rod-types of AlO NP is strengthened by a high aspect ratio and, subsequently, this accumulation has the potential to influence immune functions in an exposed host. PMID:27042761

  15. Quantitative Assessment of Altered Rectal Mucosal Permeability Due to Rectally Applied Nonoxynol-9, Biopsy, and Simulated Intercourse

    PubMed Central

    Fuchs, Edward J.; Grohskopf, Lisa A.; Lee, Linda A.; Bakshi, Rahul P.; Hendrix, Craig W.

    2013-01-01

    Background. Microbicide toxicity may reduce the efficacy of topical preexposure prophylaxis for human immunodeficiency virus (HIV) transmission. Noninvasive quantitative measures of microbicide toxicity would usefully inform microbicide development. Methods. Ten subjects received 3 one-time interventions: 5 mL of Normosol-R fluid alone (negative control), 5 mL of 2% nonoxynol-9 (N-9) gel, and 5 mL of Normosol-R with coital simulation and sigmoidoscopic biopsy (CS + BX). Each dose of N-9 and Normosol-R contained 500 µCi of 99mtechnetium–diethylene triamine pentaacetic acid. Plasma and urine radioactivity was assessed over 24 hours. Results. The plasma radioisotope concentration peaked 1 hour after N-9 dosing. The mean maximum radioisotope concentration after N-9 receipt was 12.0 times (95% confidence interval [CI], 6.8–21.0) and 8.4 times (95% CI, 5.2–13.5) the mean concentration after Normosol-R control receipt and CS + BX receipt, respectively; paired differences persisted for 24 hours. After N-9 dosing, the urine isotope level was 3.6 times (95% CI, 1.1–11.4) the level observed 8 hours after Normosol-R control receipt and 4.0 times (95% CI, 1.4–11.4) the level observed 4 hours after CS + BX receipt. Permeability after CS + BX receipt was greater than that after Normosol-R control receipt in 0–2-hour urine specimens only (mean permeability, 2.4; 95% CI, 1.0–5.8) but was not greater in blood. Conclusions. Plasma sampling after rectal radioisotope administration provided quantitative estimates of altered mucosal permeability after chemical and mechanical stresses. Permeability testing may provide a useful noninvasive adjunct to assess the mucosal effects of candidate microbicides. Clinical Trials Registration. NCT00389311. PMID:23325915

  16. Inhibition of tomato (Solanum lycopersicum L.) root growth by cyanamide is due to altered cell division, phytohormone balance and expansin gene expression.

    PubMed

    Soltys, Dorota; Rudzińska-Langwald, Anna; Gniazdowska, Agnieszka; Wiśniewska, Anita; Bogatek, Renata

    2012-11-01

    Cyanamide (CA) has been reported as a natural compound produced by hairy vetch (Vicia villosa Roth.) and it was shown also to be an allelochemical, responsible for strong allelopathic potential in this species. CA phytotoxicity has been demonstrated on various plant species, but to date little is known about its mode of action at cellular level. Treatment of tomato (Solanum lycopersicum L.) roots with CA (1.2 mM) resulted in inhibition of growth accompanied by alterations in cell division, and imbalance of plant hormone (ethylene and auxin) homeostasis. Moreover, the phytotoxic effect of CA was also manifested by modifications in expansin gene expression, especially in expansins responsible for cell wall remodeling after the cytokinesis (LeEXPA9, LeEXPA18). Based on these results the phytotoxic activity of CA on growth of roots of tomato seedlings is likely due to alterations associated with cell division. PMID:22847024

  17. Molecular Characterization of Reactive Oxygen Species in Myocardial Ischemia-Reperfusion Injury

    PubMed Central

    Zhou, Tingyang; Chuang, Chia-Chen; Zuo, Li

    2015-01-01

    Myocardial ischemia-reperfusion (I/R) injury is experienced by individuals suffering from cardiovascular diseases such as coronary heart diseases and subsequently undergoing reperfusion treatments in order to manage the conditions. The occlusion of blood flow to the tissue, termed ischemia, can be especially detrimental to the heart due to its high energy demand. Several cellular alterations have been observed upon the onset of ischemia. The danger created by cardiac ischemia is somewhat paradoxical in that a return of blood to the tissue can result in further damage. Reactive oxygen species (ROS) have been studied intensively to reveal their role in myocardial I/R injury. Under normal conditions, ROS function as a mediator in many cell signaling pathways. However, stressful environments significantly induce the generation of ROS which causes the level to exceed body's antioxidant defense system. Such altered redox homeostasis is implicated in myocardial I/R injury. Despite the detrimental effects from ROS, low levels of ROS have been shown to exert a protective effect in the ischemic preconditioning. In this review, we will summarize the detrimental role of ROS in myocardial I/R injury, the protective mechanism induced by ROS, and potential treatments for ROS-related myocardial injury. PMID:26509170

  18. Myocardial reverse remodeling: how far can we rewind?

    PubMed

    Rodrigues, Patrícia G; Leite-Moreira, Adelino F; Falcão-Pires, Inês

    2016-06-01

    Heart failure (HF) is a systemic disease that can be divided into HF with reduced ejection fraction (HFrEF) and with preserved ejection fraction (HFpEF). HFpEF accounts for over 50% of all HF patients and is typically associated with high prevalence of several comorbidities, including hypertension, diabetes mellitus, pulmonary hypertension, obesity, and atrial fibrillation. Myocardial remodeling occurs both in HFrEF and HFpEF and it involves changes in cardiac structure, myocardial composition, and myocyte deformation and multiple biochemical and molecular alterations that impact heart function and its reserve capacity. Understanding the features of myocardial remodeling has become a major objective for limiting or reversing its progression, the latter known as reverse remodeling (RR). Research on HFrEF RR process is broader and has delivered effective therapeutic strategies, which have been employed for some decades. However, the RR process in HFpEF is less clear partly due to the lack of information on HFpEF pathophysiology and to the long list of failed standard HF therapeutics strategies in these patient's outcomes. Nevertheless, new proteins, protein-protein interactions, and signaling pathways are being explored as potential new targets for HFpEF remodeling and RR. Here, we review recent translational and clinical research in HFpEF myocardial remodeling to provide an overview on the most important features of RR, comparing HFpEF with HFrEF conditions. PMID:26993225

  19. Adipose stem cell sheets improved cardiac function in the rat myocardial infarction, but did not alter cardiac contractile responses to β-adrenergic stimulation.

    PubMed

    Otsuki, Yuki; Nakamura, Yoshinobu; Harada, Shingo; Yamamoto, Yasutaka; Ogino, Kazuhide; Morikawa, Kumi; Ninomiya, Haruaki; Miyagawa, Shigeru; Sawa, Yoshiki; Hisatome, Ichiro; Nishimura, Motonobu

    2015-01-01

    Adipose stem cells (ASCs) are a source of regenerative cells available for autologous transplantation to hearts. We compared protective actions of ASC sheets on rat myocardial infarction (MI) in comparison with those of skeletal myoblast cell sheets. Their effects on infarcted hearts were evaluated by biological, histochemical as well as physiological analyses. ASC sheets secreted higher concentrations of angiogenic factors (HGF, VEGF, and bFGF; P < 0.05) under normoxic and hypoxic conditions than those of myoblast cell sheets, associated with reduction of cell apoptosis (P < 0.05). Like myoblast cell sheets, ASC sheets improved cardiac function (P < 0.05) and decreased the plasma level of ANP (P < 0.05) in MI hearts. ASC sheets restored cardiac remodeling characterized by fibrosis, cardiac hypertrophy and impaired angiogenesis (P < 0.05), which was associated with increases in angiogenic factors (P < 0.05). In isolated perfused rat hearts, ASC sheets improved both systolic and diastolic functions, which was comparable to cardiac functions of myoblast cell sheets, while both cell sheets failed to restore cardiac contractile response to either isoproterenol, pimobendan or dibutyryl cAMP. These results indicated that ASC sheets improved cardiac function and remodeling of MI hearts mediated by their paracrine action and this improvement was comparable to those by myoblast cell sheets. PMID:25749147

  20. 2013 Immune Risk Standing Review Panel Evidence Review for: The Risk of Crew Adverse Health Event Due to Altered Immune Response

    NASA Technical Reports Server (NTRS)

    Steinberg, Susan

    2014-01-01

    The 2013 Immune Risk Standing Review Panel (from here on referred to as the SRP) met for a site visit in Houston, TX on February 3-4, 2014. The SRP reviewed the new Evidence Report for the Risk of Crew Adverse Health Event Due to Altered Immune Response (from here on referred to as the 2013 Immune Evidence Report), as well as the Research Plan for this Risk that is in the current version of the Human Research Program’s (HRP) Integrated Research Plan (IRP).

  1. Protective effects of Labisia pumila var. alata on biochemical and histopathological alterations of cardiac muscle cells in isoproterenol-induced myocardial infarction rats.

    PubMed

    Dianita, Roza; Jantan, Ibrahim; Amran, Athirah Z; Jalil, Juriyati

    2015-01-01

    The study was designed to evaluate the cardioprotective effects of the standardized aqueous and 80% ethanol extracts of Labisia pumila var. alata (LPva) in isoproterenol (ISO)-induced myocardial infarction (MI) in rats. The extracts were administered to Wistar rats orally for 28 days with three doses (100, 200 and 400 mg/kg of body weight) prior to ISO (85 mg/kg)-induced MI in two doses on day 29 and 30. The sera and hearts were collected for biochemical and histopathological analysis after the rats were sacrificed 48 h after the first induction. The main components of the extracts, gallic acid, alkylresorcinols and flavonoids were identified and quantitatively analyzed in the extracts by using a validated reversed phase HPLC method. The extracts showed significant protective effects as pretreated rats showed a significant dose-dependent decrease (p < 0.05) in cardiac enzyme activities, i.e., cardiac troponin I (cTnI), creatine kinase MB isoenzyme (CK-MB), lactate dehydrogenase (LDH), alanine transaminase (ALT) and aspartate transaminase (AST), when compared with ISO-control rats. There were significant rises (p < 0.05) in the activity of oxidase enzymes, i.e., glutathione peroxide (GPx), catalase (CAT) and superoxide dismutase (SOD) of the pretreated rats, when compared with ISO-control group. Histopathological examination showed an improvement in membrane cell integrity in pre-treated rats compared to untreated rats. The major components of LPva extracts can be used as their biomarkers and contributed to the cardioprotective effects against ISO-induced MI rats. PMID:25786162

  2. Altered myocardial perfusion in patients with angina pectoris or silent ischemia during exercise as assessed by quantitative thallium-201 single-photon emission computed tomography

    SciTech Connect

    Mahmarian, J.J.; Pratt, C.M.; Cocanougher, M.K.; Verani, M.S. )

    1990-10-01

    The extent of abnormally perfused myocardium was compared in patients with and without chest pain during treadmill exercise from a large, relatively low-risk consecutive patient population (n = 356) referred for quantitative thallium-201 single-photon emission computed tomography (SPECT). All patients had concurrent coronary angiography. Patients were excluded if they had prior coronary angioplasty or bypass surgery. Tomographic images were assessed visually and from computer-generated polar maps. Chest pain during exercise was as frequent in patients with normal coronary arteries (12%) as in those with significant (greater than 50% stenosis) coronary artery disease (CAD) (14%). In the 219 patients with significant CAD, silent ischemia was fivefold more common than symptomatic ischemia (83% versus 17%, p = 0.0001). However, there were no differences in the extent, severity, or distribution of coronary stenoses in patients with silent or symptomatic ischemia. Our major observation was that the extent of quantified SPECT perfusion defects was nearly identical in patients with (20.9 +/- 15.9%) and without (20.5 +/- 15.6%) exertional chest pain. The sensitivity for detecting the presence of CAD was significantly improved with quantitative SPECT compared with stress electrocardiography (87% versus 65%, p = 0.0001). Although scintigraphic and electrocardiographic evidence of exercise-induced ischemia were comparable in patients with chest pain (67% versus 73%, respectively; p = NS), SPECT was superior to stress electrocardiography for detecting silent myocardial ischemia. The majority of patients in this study with CAD who developed ischemia during exercise testing were asymptomatic, although they exhibited an angiographic profile and extent of abnormally perfused myocardium similar to those of patients with symptomatic ischemia.

  3. Gender Differences in Non-Ischemic Myocardial Remodeling: Are They Due to Estrogen Modulation of Cardiac Mast Cells and/or Membrane Type 1 Matrix Metalloproteinase

    PubMed Central

    Janicki, Joseph S.; Spinale, Francis G.; Levick, Scott P.

    2013-01-01

    SUMMARY This review is focused on gender differences in cardiac remodeling secondary to sustained increases in cardiac volume (VO) and generated pressure (PO). Estrogen has been shown to favorably alter the course of VO-induced remodeling. That is, the VO-induced increased extracellular matrix proteolytic activity and mast cell degranulation responsible for the adverse cardiac remodeling in males and ovariectomized rodents do not occur in intact premenopausal females. While less is known regarding the mechanisms responsible for female cardioprotection in PO-induced stress, gender differences in remodeling have been reported indicating the ability of premenopausal females to adequately compensate. In view of the fact that, in male mice with PO, mast cells have been shown to play a role in the adverse remodeling suggests favorable estrogen modification of mast cell phenotype may also be responsible for cardioprotection in females with PO. Thus, while evidence is accumulating regarding premenopausal females being cardioprotected; there remains the need for in-depth studies to identify critical downstream molecular targets that are under the regulation of estrogen and relevant to cardiac remodeling. Such studies would result in the development of therapy which provides cardioprotection while avoiding the adverse effects of systemic estrogen delivery. PMID:23417570

  4. [Vectorcardiographic diagnosis of the myocardial inactivatable zone].

    PubMed

    de Micheli, A; Medrano, G A

    1989-01-01

    Clinical importance of the vectorcardiographic exploration (distant and spatial) of the myocardial electrical phenomenon is emphasized. This technique constitutes a useful integration of electrocardiographic exploration (near and analytical). The more characteristic morphological and chronological changes due to an inactivatable area are discussed in the light of ventricular myocardial depolarization. Some typical vectorcardiographic features corresponding to the presence of a myocardial inactivatable zone are presented. The utility of the complementary elements which vectorcardiography can bring to electrocardiography is emphasized. Both of these procedures integrate a rational exploration of electrical activity of the myocardium, the solid base of prognostic and therapeutic decisions in cases of myocardial infarction. PMID:2669657

  5. A Mouse Model Suggests Two Mechanisms for Thyroid Alterations in Infantile Cystinosis: Decreased Thyroglobulin Synthesis Due to Endoplasmic Reticulum Stress/Unfolded Protein Response and Impaired Lysosomal Processing

    PubMed Central

    Gaide Chevronnay, H. P.; Janssens, V.; Van Der Smissen, P.; Liao, X. H.; Abid, Y.; Nevo, N.; Antignac, C.; Refetoff, S.; Cherqui, S.; Pierreux, C. E.

    2015-01-01

    Thyroid hormones are released from thyroglobulin (Tg) in lysosomes, which are impaired in infantile/nephropathic cystinosis. Cystinosis is a lysosomal cystine storage disease due to defective cystine exporter, cystinosin. Cystinotic children develop subclinical and then overt hypothyroidism. Why hypothyroidism is the most frequent and earliest endocrine complication of cystinosis is unknown. We here defined early alterations in Ctns−/− mice thyroid and identified subcellular and molecular mechanisms. At 9 months, T4 and T3 plasma levels were normal and TSH was moderately increased (∼4-fold). By histology, hyperplasia and hypertrophy of most follicles preceded colloid exhaustion. Increased immunolabeling for thyrocyte proliferation and apoptotic shedding indicated accelerated cell turnover. Electron microscopy revealed endoplasmic reticulum (ER) dilation, apical lamellipodia indicating macropinocytic colloid uptake, and lysosomal cystine crystals. Tg accumulation in dilated ER contrasted with mRNA down-regulation. Increased expression of ER chaperones, glucose-regulated protein of 78 kDa and protein disulfide isomerase, associated with alternative X-box binding protein-1 splicing, revealed unfolded protein response (UPR) activation by ER stress. Decreased Tg mRNA and ER stress suggested reduced Tg synthesis. Coordinated increase of UPR markers, activating transcription factor-4 and C/EBP homologous protein, linked ER stress to apoptosis. Hormonogenic cathepsins were not altered, but lysosome-associated membrane protein-1 immunolabeling disclosed enlarged vesicles containing iodo-Tg and impaired lysosomal fusion. Isopycnic fractionation showed iodo-Tg accumulation in denser lysosomes, suggesting defective lysosomal processing and hormone release. In conclusion, Ctns−/− mice showed the following alterations: 1) compensated primary hypothyroidism and accelerated thyrocyte turnover; 2) impaired Tg production linked to ER stress/UPR response; and 3) altered

  6. Antiplatelet efficacy of P2Y12 inhibitors (prasugrel, ticagrelor, clopidogrel) in patients treated with mild therapeutic hypothermia after cardiac arrest due to acute myocardial infarction.

    PubMed

    Bednar, Frantisek; Kroupa, Josef; Ondrakova, Martina; Osmancik, Pavel; Kopa, Milos; Motovska, Zuzana

    2016-05-01

    Survivors after cardiac arrest (CA) due to AMI undergo PCI and then receive dual antiplatelet therapy. Mild therapeutic hypothermia (MTH) is recommended for unconscious patients after CA to improve neurological outcomes. MTH can attenuate the effectiveness of P2Y12 inhibitors by reducing gastrointestinal absorption and metabolic activation. The combined effect of these conditions on the efficacy of P2Y12 inhibitors is unknown. We compared the antiplatelet efficacies of new P2Y12 inhibitors in AMI patients after CA treated with MTH. Forty patients after CA for AMI treated with MTH and received one P2Y12 inhibitor (clopidogrel, prasugrel or ticagrelor) were enrolled in a prospective observational single-center study. Platelet inhibition was measured by VASP (PRI) on days 1, 2, and 3 after drug administration. In-hospital clinical data and 1-year survival data were obtained. The proportion of patients with ineffective platelet inhibition (PRI > 50 %, high on-treatment platelet reactivity) for clopidogrel, prasugrel, and ticagrelor was 77 vs. 19 vs. 1 % on day 1; 77 vs. 17 vs. 0 % on day 2; and 85 vs. 6 vs. 0 % on day 3 (P < 0.001). The platelet inhibition was significantly worse in clopidogrel group than in prasugrel or ticagrelor group. Prasugrel and ticagrelor are very effective for platelet inhibition in patients treated with MTH after CA due to AMI, but clopidogrel is not. Using prasugrel or ticagrelor seems to be a more suitable option in this high-risk group of acute patients. PMID:26340851

  7. Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Space flight

    NASA Technical Reports Server (NTRS)

    Bloomberg, Jacob J.; Reschke, Millard F.; Clement, Gilles R.; Mulavara, Ajitkumar P.; Taylor, Laura C..

    2015-01-01

    Control of vehicles and other complex systems is a high-level integrative function of the central nervous system (CNS). It requires well-functioning subsystem performance, including good visual acuity, eye-hand coordination, spatial and geographic orientation perception, and cognitive function. Evidence from space flight research demonstrates that the function of each of these subsystems is altered by removing gravity, a fundamental orientation reference, which is sensed by vestibular, proprioceptive, and haptic receptors and used by the CNS for spatial orientation, posture, navigation, and coordination of movements. The available evidence also shows that the degree of alteration of each subsystem depends on a number of crew- and mission-related factors. There is only limited operational evidence that these alterations cause functional impacts on mission-critical vehicle (or complex system) control capabilities. Furthermore, while much of the operational performance data collected during space flight has not been available for independent analysis, those that have been reviewed are somewhat equivocal owing to uncontrolled (and/or unmeasured) environmental and/or engineering factors. Whether this can be improved by further analysis of previously inaccessible operational data or by development of new operational research protocols remains to be seen. The true operational risks will be estimable only after we have filled the knowledge gaps and when we can accurately assess integrated performance in off-nominal operational settings (Paloski et al. 2008). Thus, our current understanding of the Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Space flight is limited primarily to extrapolation of scientific research findings, and, since there are limited ground-based analogs of the sensorimotor and vestibular changes associated with space flight, observation of their functional

  8. Prognostic Significance of Imaging Myocardial Sympathetic Innervation.

    PubMed

    Malhotra, Saurabh; Fernandez, Stanley F; Fallavollita, James A; Canty, John M

    2015-08-01

    There has been a longstanding interest in understanding whether the presence of inhomogeneity in myocardial sympathetic innervation can predict patients at risk of sudden cardiac arrest from lethal ventricular arrhythmias. The advent of radiolabeled norepinephrine analogs has allowed this to be imaged in patients with ischemic and non-ischemic cardiomyopathy using single, photon emission computed tomography (SPECT) and positron emission tomography (PET). Several observational studies have demonstrated that globally elevated myocardial sympathetic tone (as reflected by reduced myocardial norepinephrine analog uptake) can predict composite cardiac end-points including total cardiovascular mortality. More recent studies have indicated that quantifying the extent of regional denervation can predict the risk of lethal ventricular arrhythmias and sudden cardiac death. This review will summarize our current understanding of the prognostic significance of altered myocardial sympathetic innervation. PMID:26087899

  9. Doxorubicin In Vivo Rapidly Alters Expression and Translation of Myocardial Electron Transport Chain Genes, Leads to ATP Loss and Caspase 3 Activation

    PubMed Central

    Pointon, Amy V.; Walker, Tracy M.; Phillips, Kate M.; Luo, Jinli; Riley, Joan; Zhang, Shu-Dong; Parry, Joel D.; Lyon, Jonathan J.; Marczylo, Emma L.; Gant, Timothy W.

    2010-01-01

    Background Doxorubicin is one of the most effective anti-cancer drugs but its use is limited by cumulative cardiotoxicity that restricts lifetime dose. Redox damage is one of the most accepted mechanisms of toxicity, but not fully substantiated. Moreover doxorubicin is not an efficient redox cycling compound due to its low redox potential. Here we used genomic and chemical systems approaches in vivo to investigate the mechanisms of doxorubicin cardiotoxicity, and specifically test the hypothesis of redox cycling mediated cardiotoxicity. Methodology/Principal Findings Mice were treated with an acute dose of either doxorubicin (DOX) (15 mg/kg) or 2,3-dimethoxy-1,4-naphthoquinone (DMNQ) (25 mg/kg). DMNQ is a more efficient redox cycling agent than DOX but unlike DOX has limited ability to inhibit gene transcription and DNA replication. This allowed specific testing of the redox hypothesis for cardiotoxicity. An acute dose was used to avoid pathophysiological effects in the genomic analysis. However similar data were obtained with a chronic model, but are not specifically presented. All data are deposited in the Gene Expression Omnibus (GEO). Pathway and biochemical analysis of cardiac global gene transcription and mRNA translation data derived at time points from 5 min after an acute exposure in vivo showed a pronounced effect on electron transport chain activity. This led to loss of ATP, increased AMPK expression, mitochondrial genome amplification and activation of caspase 3. No data gathered with either compound indicated general redox damage, though site specific redox damage in mitochondria cannot be entirely discounted. Conclusions/Significance These data indicate the major mechanism of doxorubicin cardiotoxicity is via damage or inhibition of the electron transport chain and not general redox stress. There is a rapid response at transcriptional and translational level of many of the genes coding for proteins of the electron transport chain complexes. Still

  10. Age-associated impairement in endpoint accuracy of goal-directed contractions performed with two fingers is due to altered activation of the synergistic muscles.

    PubMed

    Chen, Yen-Ting; Pinto Neto, Osmar; de Miranda Marzullo, Ana Carolina; Kennedy, Deanna M; Fox, Emily J; Christou, Evangelos A

    2012-07-01

    The purpose of this study was to determine whether older adults compared with young adults exhibit impaired end-point accuracy during a two-finger task due to altered activation of the contributing synergistic muscles. Nine young (21.3 years ± 1.6 years, 4 men) and 9 older (73.1 years ± 6.4 years, 5 men) were instructed to accurately match the center of a target with concurrent abduction of the index and little fingers (synergistic two-finger task). The target comprised of 20% MVC and 200 ms. Visual feedback of the force trajectory and target was provided 1s after each trial. Subjects completed 40 trials and the last 10 were used for analysis. Endpoint accuracy was quantified as the normalized deviation from the target in terms of peak force (peak force error), time-to-peak force (time-to-peak force error), and a combination of the two (overall error). Motor output variability was quantified as the standard deviation and coefficient of variation (CV) of peak force and time to peak force. The neural activation of the involved synergist muscles (first dorsal interosseus (FDI) and abductor digiti minimi (ADM)) was quantified with the electromyography (EMG) amplitude (root mean square) and its frequency structure (wavelet analysis). Older adults exhibited significantly greater peak force (46.7 ± 10% vs. 24.9 ± 3.2%) and overall endpoint error (68.5 ± 9.7% vs. 41.7 ± 4.3%), whereas the time to peak force error was similar for the two age groups. Older adults also exerted greater peak force variability than young adults, as quantified by the CV of peak force (34.3 ± 3.5% vs. 24.1 ± 2.3%). The greater peak force error in older adults was associated with changes in the activation of the ADM muscle but not the FDI. Specifically, greater peak force error was associated with greater power from 13-30 Hz and lesser power from 30-60 Hz. These results, therefore, suggest that older adults compared with young adults exhibit impaired endpoint force accuracy during a two

  11. Assessment of myocardial metabolic flexibility and work efficiency in human type 2 diabetes using 16-[18F]fluoro-4-thiapalmitate, a novel PET fatty acid tracer.

    PubMed

    Mather, K J; Hutchins, G D; Perry, K; Territo, W; Chisholm, R; Acton, A; Glick-Wilson, B; Considine, R V; Moberly, S; DeGrado, T R

    2016-03-15

    Altered myocardial fuel selection likely underlies cardiac disease risk in diabetes, affecting oxygen demand and myocardial metabolic flexibility. We investigated myocardial fuel selection and metabolic flexibility in human type 2 diabetes mellitus (T2DM), using positron emission tomography to measure rates of myocardial fatty acid oxidation {16-[(18)F]fluoro-4-thia-palmitate (FTP)} and myocardial perfusion and total oxidation ([(11)C]acetate). Participants underwent paired studies under fasting conditions, comparing 3-h insulin + glucose euglycemic clamp conditions (120 mU·m(-2)·min(-1)) to 3-h saline infusion. Lean controls (n = 10) were compared with glycemically controlled volunteers with T2DM (n = 8). Insulin augmented heart rate, blood pressure, and stroke index in both groups (all P < 0.01) and significantly increased myocardial oxygen consumption (P = 0.04) and perfusion (P = 0.01) in both groups. Insulin suppressed available nonesterified fatty acids (P < 0.0001), but fatty acid concentrations were higher in T2DM under both conditions (P < 0.001). Insulin-induced suppression of fatty acid oxidation was seen in both groups (P < 0.0001). However, fatty acid oxidation rates were higher under both conditions in T2DM (P = 0.003). Myocardial work efficiency was lower in T2DM (P = 0.006) and decreased in both groups with the insulin-induced increase in work and shift in fuel utilization (P = 0.01). Augmented fatty acid oxidation is present under baseline and insulin-treated conditions in T2DM, with impaired insulin-induced shifts away from fatty acid oxidation. This is accompanied by reduced work efficiency, possibly due to greater oxygen consumption with fatty acid metabolism. These observations suggest that improved fatty acid suppression, or reductions in myocardial fatty acid uptake and retention, could be therapeutic targets to improve myocardial ischemia tolerance in T2DM. PMID:26732686

  12. 2013 Immune Risk Standing Review Panel Research Plan Review for: The Risk of Crew Adverse Health Event Due to Altered Immune Response

    NASA Technical Reports Server (NTRS)

    Steinberg, Susan

    2014-01-01

    The 2013 Immune Risk Standing Review Panel (from here on referred to as the SRP) participated in a meeting with representatives from the Human Research Program (HRP) Human Health Countermeasures (HHC) Element and HRP management on February 3-4, 2014 in Houston, TX to review the updated Research Plan for the Risk of Crew Adverse Health Event Due to Altered Immune Response in the HRP Integrated Research Plan. The SRP is impressed with the work the immune discipline has done since the 2012 SRP review and agrees with the new wording of the Gaps, no longer questions, now statements. The SRP also likes the addition of adding targets for closing the Gaps, but it is not clear how they got to some of the interim stages (interval percentages). A major concern that the SRP has mentioned since the initial 2009 SRP meeting is that there is still not enough emphasis on the interdisciplinary aspect of the immune risk associated with other risks (i.e., nutrition, radiation, etc.). The SRP recommends that a "translational SRP" or advisory group be developed that is composed of members from all of the HRP SRPs. The SRP also thinks that the immune discipline should consider a more systems biology approach. Lastly, the SRP is concerned that the risks observed in research from low Earth orbit (LEO) missions may not accurately reflect all the risks of longer duration flight beyond LEO. Also, there does not seem to be a concern for immune responses that may occur when someone is in space longer than six months, for example, a Mars mission would take three years. The absence of disease in past and current flight scenarios does not mean the risk may not be there in future flight settings.

  13. Myocardial imaging. Coxsackie myocarditis

    SciTech Connect

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

    1986-09-01

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

  14. Determinants of myocardial conduction velocity: implications for arrhythmogenesis

    PubMed Central

    King, James H.; Huang, Christopher L.-H.; Fraser, James A.

    2013-01-01

    Slowed myocardial conduction velocity (θ) is associated with an increased risk of re-entrant excitation, predisposing to cardiac arrhythmia. θ is determined by the ion channel and physical properties of cardiac myocytes and by their interconnections. Thus, θ is closely related to the maximum rate of action potential (AP) depolarization [(dV/dt)max], as determined by the fast Na+ current (INa); the axial resistance (ra) to local circuit current flow between cells; their membrane capacitances (cm); and to the geometrical relationship between successive myocytes within cardiac tissue. These determinants are altered by a wide range of pathophysiological conditions. Firstly, INa is reduced by the impaired Na+ channel function that arises clinically during heart failure, ischemia, tachycardia, and following treatment with class I antiarrhythmic drugs. Such reductions also arise as a consequence of mutations in SCN5A such as those occurring in Lenègre disease, Brugada syndrome (BrS), sick sinus syndrome, and atrial fibrillation (AF). Secondly, ra, may be increased due to gap junction decoupling following ischemia, ventricular hypertrophy, and heart failure, or as a result of mutations in CJA5 found in idiopathic AF and atrial standstill. Finally, either ra or cm could potentially be altered by fibrotic change through the resultant decoupling of myocyte–myocyte connections and coupling of myocytes with fibroblasts. Such changes are observed in myocardial infarction and cardiomyopathy or following mutations in MHC403 and SCN5A resulting in hypertrophic cardiomyopathy (HCM) or Lenègre disease, respectively. This review defines and quantifies the determinants of θ and summarizes experimental evidence that links changes in these determinants with reduced myocardial θ and arrhythmogenesis. It thereby identifies the diverse pathophysiological conditions in which abnormal θ may contribute to arrhythmia. PMID:23825462

  15. Thermoinducible filamentation in Escherichia coli due to an altered RNA polymerase beta subunit is suppressed by high levels of ppGpp.

    PubMed Central

    Vinella, D; D'Ari, R

    1994-01-01

    The Escherichia coli strain known as GC2553, FB8, UTH1038, or K12S (Luria), considered an F- lambda- wild-type strain, is shown here to carry a cryptic mutation, ftsR1, causing nonlethal filamentation during exponential growth in Luria-Bertani (LB) broth at 42 degrees C and the inability to grow in salt-free LB broth at 42 degrees C. The ftsR1 mutation is completely suppressed in genetic backgrounds which increase RelA-dependent synthesis of the nucleotide ppGpp, i.e., argS201 (Mecr) and alaS21 (Mecr) mutations, affecting aminoacyl-tRNA synthetases, or the presence of a plac-relA' plasmid. These backgrounds also confer resistance in LB broth to the beta-lactam mecillinam, an antibiotic which specifically inhibits penicillin-binding protein 2 and, in wild-type cells, causes an indirect block in cell division. Furthermore, the ftsR1 mutant (but not an isogenic ftsR+ strain) is sensitive to mecillinam in minimal glucose medium at 37 degrees C. Since the division block caused by mecillinam can be overcome by overproduction of the cell division protein FtsZ, we tested the effect of plasmid pZAQ (carrying the ftsZ, ftsA, and ftsQ genes) on the ftsR1 mutant; it suppressed the filamentation in LB broth and the mecillinam sensitivity on minimal glucose medium at 37 degrees C but not the growth defect in salt-free LB broth at 42 degrees C. Genetic analysis indicated that the full phenotype of the ftsR1 mutant is due to a single mutation in the rpoB gene (90 min), coding for the beta subunit of RNA polymerase; we call this allele rpoB369(Fts). We propose that the rpoB369(Fts) mutation alters the specificity of the polymerase and that the mutant enzyme can recover normal activity in the presence of high salt concentrations or via interaction with the nucleotide ppGpp. PMID:8106339

  16. A large pseudoaneurysm of the left cardiac ventricle in a 57-year-old patient after urgent coronary artery bypass grafting and surgical mitral valve replacement due to acute myocardial infarction.

    PubMed

    Wieczorek, Joanna; Mizia-Stec, Katarzyna; Rybicka-Musialik, Anna; Janusiewicz, Piotr; Malinowski, Marcin; Deja, Marek A

    2014-12-01

    We present a rare case of a left ventricular pseudoaneurysm in a patient after inferior wall myocardial infarction. The infarction was complicated with acute mitral insufficiency, pulmonary edema, and cardiogenic shock. Urgent surgical mitral valve replacement and coronary artery bypass grafting were performed. After several months, the patient was hospitalized again because of deterioration of exercise tolerance and symptoms of acute congestive heart failure. A large pseudoaneurysm of the left ventricle was recognized and successfully treated surgically. PMID:26336464

  17. A large pseudoaneurysm of the left cardiac ventricle in a 57-year-old patient after urgent coronary artery bypass grafting and surgical mitral valve replacement due to acute myocardial infarction

    PubMed Central

    Mizia-Stec, Katarzyna; Rybicka-Musialik, Anna; Janusiewicz, Piotr; Malinowski, Marcin; Deja, Marek A.

    2014-01-01

    We present a rare case of a left ventricular pseudoaneurysm in a patient after inferior wall myocardial infarction. The infarction was complicated with acute mitral insufficiency, pulmonary edema, and cardiogenic shock. Urgent surgical mitral valve replacement and coronary artery bypass grafting were performed. After several months, the patient was hospitalized again because of deterioration of exercise tolerance and symptoms of acute congestive heart failure. A large pseudoaneurysm of the left ventricle was recognized and successfully treated surgically. PMID:26336464

  18. Invasion of a semi-arid shrubland by annual grasses increases autotrophic and heterotrophic soil respiration rates due to altered soil moisture and temperature patterns

    NASA Astrophysics Data System (ADS)

    Mauritz, M.; Hale, I.; Lipson, D.

    2010-12-01

    Shrub <-> grassland conversions are a globally occurring phenomenon altering habitat structure, quality and nutrient cycling. Grasses and shrubs differ in their above and belowground biomass allocation, root architecture, phenology, litter quality and quantity. Conversion affects soil microbial communities, soil moisture and temperature and carbon (C) allocation patterns. However, the effect of conversion on C storage is regionally variable and there is no consistent direction of change. In Southern California invasion by annual grasses is a major threat to native shrub communities and it has been proposed that grass invasion increases NPP and ecosystem C storage (Wolkovich et al, 2009). In order to better understand how this shrub <-> grassland conversion changes ecosystem C storage it is important to understand the partitioning of soil respiration into autotrophic and heterotrophic components. Respiration was measured in plots under shrubs and grasses from February when it was cold and wet to July when it was hot and dry, capturing seasonal transitions in temperature and water availability. Roots were excluded under shrubs and grasses with root exclusion cores to quantify heterotrophic respiration. Using total soil respiration (Rt) = autotrophic respiration (root) (Ra)+ heterotrophic respiration (microbial) (Rh) the components contributing to total soil respiration can be evaluated. Respiration, soil moisture and temperature were measured daily at four hour intervals using Licor 8100 automated chamber measurements. Throughout the measurement period, Rt under grasses exceeded Rt under shrubs. Higher Rt levels under grasses were mainly due to higher Ra in grasses rather than changes in Rh. On average grass Ra was almost double shrub Ra. Higher grass respiration levels are partially explained by differences in soil moisture and temperature between shrubs and grasses. Respiration rates responded similarly to seasonal transitions regardless of treatment although Ra

  19. Calpain inhibition preserves myocardial structure and function following myocardial infarction.

    PubMed

    Mani, Santhosh K; Balasubramanian, Sundaravadivel; Zavadzkas, Juozas A; Jeffords, Laura B; Rivers, William T; Zile, Michael R; Mukherjee, Rupak; Spinale, Francis G; Kuppuswamy, Dhandapani

    2009-11-01

    Cardiac pathology, such as myocardial infarction (MI), activates intracellular proteases that often trigger programmed cell death and contribute to maladaptive changes in myocardial structure and function. To test whether inhibition of calpain, a Ca(2+)-dependent cysteine protease, would prevent these changes, we used a mouse MI model. Calpeptin, an aldehydic inhibitor of calpain, was intravenously administered at 0.5 mg/kg body wt before MI induction and then at the same dose subcutaneously once per day. Both calpeptin-treated (n = 6) and untreated (n = 6) MI mice were used to study changes in myocardial structure and function after 4 days of MI, where end-diastolic volume (EDV) and left ventricular ejection fraction (EF) were measured by echocardiography. Calpain activation and programmed cell death were measured by immunohistochemistry, Western blotting, and TdT-mediated dUTP nick-end labeling (TUNEL). In MI mice, calpeptin treatment resulted in a significant improvement in EF [EF decreased from 67 + or - 2% pre-MI to 30 + or - 4% with MI only vs. 41 + or - 2% with MI + calpeptin] and attenuated the increase in EDV [EDV increased from 42 + or - 2 microl pre-MI to 73 + or - 4 microl with MI only vs. 55 + or - 4 microl with MI + calpeptin]. Furthermore, calpeptin treatment resulted in marked reduction in calpain- and caspase-3-associated changes and TUNEL staining. These studies indicate that calpain contributes to MI-induced alterations in myocardial structure and function and that it could be a potential therapeutic target in treating MI patients. PMID:19734364

  20. Effect of Curcuma longa and Ocimum sanctum on myocardial apoptosis in experimentally induced myocardial ischemic-reperfusion injury

    PubMed Central

    Mohanty, Ipseeta; Arya, Dharamvir Singh; Gupta, Suresh Kumar

    2006-01-01

    Background In the present investigation, the effect of Curcuma longa (Cl) and Ocimum sanctum (Os) on myocardial apoptosis and cardiac function was studied in an ischemia and reperfusion (I-R) model of myocardial injury. Methods Wistar albino rats were divided into four groups and orally fed saline once daily (sham, control IR) or Cl (100 mg/kg; Cl-IR) or Os (75 mg/kg; Os-IR) respectively for 1 month. On the 31st day, in the rats of the control IR, Cl-IR and Os-IR groups LAD occlusion was undertaken for 45 min, and reperfusion was allowed for 1 h. The hemodynamic parameters{mean arterial pressure (MAP), heart rate (HR), left ventricular end-diastolic pressure (LVEDP), left ventricular peak positive (+) LVdP/dt (rate of pressure development) and negative (-) LVdP/dt (rate of pressure decline)} were monitored at pre-set points throughout the experimental duration and subsequently, the animals were sacrificed for immunohistopathological (Bax, Bcl-2 protein expression & TUNEL positivity) and histopathological studies. Results Chronic treatment with Cl significantly reduced TUNEL positivity (p < 0.05), Bax protein (p < 0.001) and upregulated Bcl-2 (p < 0.001) expression in comparison to control IR group. In addition, Cl demonstrated mitigating effects on several myocardial injury induced hemodynamic {(+)LVdP/dt, (-) LVdP/dt & LVEDP} and histopathological perturbations. Chronic Os treatment resulted in modest modulation of the hemodynamic alterations (MAP, LVEDP) but failed to demonstrate any significant antiapoptotic effects and prevent the histopathological alterations as compared to control IR group. Conclusion In the present study, significant cardioprotection and functional recovery demonstrated by Cl may be attributed to its anti-apoptotic property. In contrast to Os, Cl may attenuate cell death due to apoptosis and prevent the impairment of cardiac performance. PMID:16504000

  1. Idiopathic calcified myocardial mass

    PubMed Central

    Patterson, David; Gibson, Derek; Gomes, Ricardo; McDonald, Lawson; Olsen, Eckhardt; Parker, John; Ross, Donald

    1974-01-01

    Patterson, D., Gibson, D., Gomes, R., McDonald, L., Olsen, E., Parker, J., and Ross, D. (1974).Thorax,29, 589-594. Idiopathic calcified myocardial mass. Myocardial calcification can be subdivided into three groups—metastatic, dystrophic or an extension inwards from the pericardium. This case in which the calcified myocardial mass was initially delineated by radiography and by echocardiography and subsequently removed does not fit into any subdivision and has been termed idiopathic. Images PMID:4279467

  2. Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Space Flight

    NASA Technical Reports Server (NTRS)

    Bloomberg, Jacob J.; Reschke, Millard F.; Clément, Gilles R.; Mulavara, Ajitkumar P.; Taylor, Laura C.

    2016-01-01

    We examine the various dimensions of the Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Space flight by reviewing the research and operational evidence demonstrating sensorimotor performance decrements during and after space flight. These sensorimotor performance decrements might affect vehicle and complex system control, including decreased visual acuity, eye-hand coordination, spatial and geographic orientation perception, and cognitive function. Sensorimotor performance decrements might also affect the ability to egress and walk away from the vehicle in case of an emergency or an extravehicular activity on a planetary surface. We also review the countermeasures that have been tested, including medication, prevention techniques and training exercises, physical rehabilitation, and mechanical devices. Furthermore, we identify the current knowledge and mitigation gaps that must be filled through further research and/or data mining efforts before the risk can be fully mitigated. We conclude that the true operational risks associated with the impacts of adaptive sensorimotor changes on mobility and crew abilities to control vehicles and other complex systems will only be estimable after the gaps have been filled and we have been able to accurately assess integrated performance in off-nominal operational settings. A large body of sensorimotor research data obtained from space flight experiments over the past half-century demonstrates significant decrements in oculomotor control, eye-hand coordination, spatial orientation, posture\\locomotor control and cognition during space flight missions. While these changes are most severe during and after G-transitions, the most crucial time for many critical operational tasks (e.g., landing and egress), only limited information is available to assess the operational impacts of these changes. Some of the operational observations are

  3. Discrete Microstructural Cues for the Attenuation of Fibrosis Following Myocardial Infarction

    PubMed Central

    Pinney, James R.; Du, Kim; Ayala, Perla; Fang, Qizhi; Sievers, Rich; Chew, Patrick; Delrosario, Lawrence; Lee, Randall J.; Desai, Tejal A.

    2014-01-01

    Chronic fibrosis caused by acute myocardial infarction (MI) leads to increased morbidity and mortality due to cardiac dysfunction. We have developed a therapeutic materials strategy that aims to mitigate myocardial fibrosis by utilizing injectable polymeric microstructures to mechanically alter the microenvironment. Polymeric microstructures were fabricated using photolithographic techniques and studied in a three-dimensional culture model of the fibrotic environment and by direct injection into the infarct zone of adult rats. Here, we show dose-dependent down-regulation of expression of genes associated with the mechanical fibrotic response in the presence of microstructures. Injection of this microstructured material into the infarct zone decreased levels of collagen and TGF-β, increased elastin deposition and vascularization in the infarcted region, and improved functional outcomes after six weeks. Our results demonstrate the efficacy of these discrete anti-fibrotic microstructures and suggest a potential therapeutic materials approach for combatting pathologic fibrosis. PMID:25047625

  4. [Myocardial responses to ischemia].

    PubMed

    Borisenko, V G; Gubareva, E A; Kade, A Kh

    2010-01-01

    The paper details the types of a myocardial response to impaired blood flow, such as myocardial stunning, hibernation, ischemic preconditioning, warm-up phenomenon, ischemic postconditioning, remodeling, and infarction. According to the pathogenesis, the authors identify several types of myocardial dysfunction in transient ischemic attack--uptake, delivery; and a mixed one. It is concluded the myocardial response to damage depends on a combination of influencing factors, a number of pathophysiological processes starting in the acute phase of ischemia achieve its peak in the late period. PMID:20564927

  5. [Myocardial viability, its importance for the therapeutic decision].

    PubMed

    Alexánderson, Erick; Ricalde, Alejandro; Meave, Aloha

    2005-01-01

    Myocardial viability detection is essential in patients with history of myocardial infarction whom develop ventricular dysfunction. Its detection influences the therapeutic decisions and the prognosis. Medical therapy in patients with ventricular dysfunction due to myocardial infarction and myocardial viability has been associated with higher morbidity and mortality rates than revascularization therapy, as well as improvements in the systolic function. Several imaging techniques used in the recognition of myocardial viability are available; these techniques are based on the assessment of the ventricular motion posterior to inotropic agents stimulation or on the demonstration of metabolic activity at the dysfunctional regions. In this study, some important aspects of each technique are reviewed, doing special emphasis in the utility of the Positron Emission Tomography (PET) which has been considered as the "gold standard" in the detection of myocardial viability. PMID:15909735

  6. Altered responsiveness to 5-HT at the crayfish neuromuscular junction due to chronic p-CPA and m-CPP treatment.

    PubMed

    Cooper, R L; Chase, R J; Tabor, J

    2001-10-19

    Serotonin (5-HT) levels in the hemolymph of crustaceans has been implied to alter aggressiveness which influences social interactions. The activation of IP3 as a second messenger cascade within crayfish motor neurons in response to application of 5-HT, suggests that the 5-HT receptor subtypes on the motor neurons are analogous to the vertebrate 5-HT2A receptors. Based on evidence in other systems, it would be expected that chronically sustained 5-HT levels in aggressive individuals would result in a compensatory negative feed-back regulation and/or that target tissues would diminish their sensitivity to high levels of circulating, free 5-HT. We addressed the issue of up- and down-regulation in the sensitivity of the responsiveness to exogenously applied 5-HT at the NMJs of crayfish in which the animals have altered endogenous 5-HT levels. Injections of the 5-HT1 and 5-HT2 vertebrate receptor agonist, 1-(3-Chlorophenyl) piperazine dihydrochloride (m-CPP), for 1 week resulted in a decreased responsiveness to application of 5-HT. The compound p-chlorophenylalanine (p-CPA) blocks the enzymatic synthesis of 5-HT and following 7 days of p-CPA injections, a super-sensitivity to exogenous application of 5-HT for both tonic and phasic neuromuscular junctions (NMJs) was observed. However, acute applications of p-CPA and m-CPP, followed by extensive saline washing, did not reveal any altered receptivity to 5-HT application. PMID:11597601

  7. Myocardial infarction size: measurement and modification

    PubMed Central

    Cairns, John A.

    1977-01-01

    The majority of in-hospital deaths from acute myocardial infarction occur as a result of the “power failure” syndrome (severe congestive heart failure and cardiogenic shock), which results from extensive loss of myocardium. The death of myocardial cells is sequential over many hours. Surrounding the central zone of necrosis in an acute myocardial infarction is a zone of ischemic myocardium whose fate might be altered by interventions during the early phase of the infarction. ST-segment mapping, serial measurement of the serum concentration of creatine phosphokinase and myocardial imaging by means of radionuclides are being developed for the noninvasive assessment of infarct size in animals and humans. A number of interventions appear to limit infarct size in animals. There have been relatively few studies in humans to date, but preliminary results suggest that infarct size might be limited by certain interventions. The research has provided important practical benefits in terms of understanding the course of acute myocardial infarction and the potential effects of conventional therapies. For the present, interventions designed to limit infarct size remain in the realm of clinical research; routine clinical use would be inappropriate. PMID:69481

  8. Alterations of physiology and gene expression due to long-term magnesium-deficiency differ between leaves and roots of Citrus reticulata.

    PubMed

    Jin, Xiao-Lin; Ma, Cui-Lan; Yang, Lin-Tong; Chen, Li-Song

    2016-07-01

    Seedlings of Ponkan (Citrus reticulata) were irrigated with nutrient solution containing 0 (Mg-deficiency) or 1mM MgSO4 (control) every two day for 16 weeks. Thereafter, we examined magnesium (Mg)-deficiency-induced changes in leaf and root gas exchange, total soluble proteins and gene expression. Mg-deficiency lowered leaf CO2 assimilation, and increased leaf dark respiration. However, Mg-deficient roots had lower respiration. Total soluble protein level was not significantly altered by Mg-deficiency in roots, but was lower in Mg-deficient leaves than in controls. Using cDNA-AFLP, we obtained 70 and 71 differentially expressed genes from leaves and roots. These genes mainly functioned in signal transduction, stress response, carbohydrate and energy metabolism, cell transport, cell wall and cytoskeleton metabolism, nucleic acid, and protein metabolisms. Lipid metabolism (Ca(2+) signals)-related Mg-deficiency-responsive genes were isolated only from roots (leaves). Although little difference existed in the number of Mg-deficiency-responsive genes between them both, most of these genes only presented in Mg-deficient leaves or roots, and only four genes were shared by them both. Our data clearly demonstrated that Mg-deficiency-induced alterations of physiology and gene expression greatly differed between leaves and roots. In addition, we focused our discussion on the causes for photosynthetic decline in Mg-deficient leaves and the responses of roots to Mg-deficiency. PMID:27163764

  9. Does cancer start in the womb? altered mammary gland development and predisposition to breast cancer due to in utero exposure to endocrine disruptors.

    PubMed

    Soto, Ana M; Brisken, Cathrin; Schaeberle, Cheryl; Sonnenschein, Carlos

    2013-06-01

    We are now witnessing a resurgence of theories of development and carcinogenesis in which the environment is again being accepted as a major player in phenotype determination. Perturbations in the fetal environment predispose an individual to disease that only becomes apparent in adulthood. For example, gestational exposure to diethylstilbestrol resulted in clear cell carcinoma of the vagina and breast cancer. In this review the effects of the endocrine disruptor bisphenol-A (BPA) on mammary development and tumorigenesis in rodents is used as a paradigmatic example of how altered prenatal mammary development may lead to breast cancer in humans who are also widely exposed to it through plastic goods, food and drink packaging, and thermal paper receipts. Changes in the stroma and its extracellular matrix led to altered ductal morphogenesis. Additionally, gestational and lactational exposure to BPA increased the sensitivity of rats and mice to mammotropic hormones during puberty and beyond, thus suggesting a plausible explanation for the increased incidence of breast cancer. PMID:23702822

  10. Identification of Temporal and Region-Specific Myocardial Gene Expression Patterns in Response to Infarction in Swine

    PubMed Central

    Nonell, Lara; Puigdecanet, Eulàlia; Astier, Laura; Solé, Francesc; Bayes-Genis, Antoni

    2013-01-01

    Molecular mechanisms associated with pathophysiological changes in ventricular remodelling due to myocardial infarction (MI) remain poorly understood. We analyzed changes in gene expression by microarray technology in porcine myocardial tissue at 1, 4, and 6 weeks post-MI. MI was induced by coronary artery ligation in 9 female pigs (30–40 kg). Animals were randomly sacrificed at 1, 4, or 6 weeks post-MI (n = 3 per group) and 3 healthy animals were also included as control group. Total RNA from myocardial samples was hybridized to GeneChip® Porcine Genome Arrays. Functional analysis was obtained with the Ingenuity Pathway Analysis (IPA) online tool. Validation of microarray data was performed by quantitative real-time PCR (qRT-PCR). More than 8,000 different probe sets showed altered expression in the remodelling myocardium at 1, 4, or 6 weeks post-MI. Ninety-seven percent of altered transcripts were detected in the infarct core and 255 probe sets were differentially expressed in the remote myocardium. Functional analysis revealed 28 genes de-regulated in the remote myocardial region in at least one of the three temporal analyzed stages, including genes associated with heart failure (HF), systemic sclerosis and coronary artery disease. In the infarct core tissue, eight major time-dependent gene expression patterns were recognized among 4,221 probe sets commonly altered over time. Altered gene expression of ACVR2B, BID, BMP2, BMPR1A, LMNA, NFKBIA, SMAD1, TGFB3, TNFRSF1A, and TP53 were further validated. The clustering of similar expression patterns for gene products with related function revealed molecular footprints, some of them described for the first time, which elucidate changes in biological processes at different stages after MI. PMID:23372767

  11. Myocardial infarction--fusion or confusion?

    PubMed

    Ardhanari, Sivakumar; Shah, Ashok J; Thakur, Ranjan K

    2009-09-01

    A patient with a dualchamber pacemaker with dynamic atrioventricular delay (AVD) experienced acute substernal chest pain. The rhythm strip in the ambulance showed intermittent ST elevation in the inferior leads. An emergent cardiac catheterization revealed nonobstructive coronary artery disease. Rate-responsive dual-chamber pacing with dynamic AVD was responsible for varying devvgrees of ventricular fusion due to competition with the patient's normal conduction. Intermittent ST elevation, evident only during ventricular fusion should have suggested secondary ventricular repolarization and not myocardial injury, but concomitant chest pain and inconspicuous bipolar pacing artifacts added to the confusion. Ventricular pacing may not only mask acute ST-T changes due to myocardial injury, but can also mimic acute myocardial infarction. PMID:19726827

  12. Combretastatin A4 disodium phosphate-induced myocardial injury.

    PubMed

    Tochinai, Ryota; Nagata, Yuriko; Ando, Minoru; Hata, Chie; Suzuki, Tomo; Asakawa, Naoyuki; Yoshizawa, Kazuhiko; Uchida, Kazumi; Kado, Shoichi; Kobayashi, Toshihide; Kaneko, Kimiyuki; Kuwahara, Masayoshi

    2016-07-01

    Histopathological and electrocardiographic features of myocardial lesions induced by combretastatin A4 disodium phosphate (CA4DP) were evaluated, and the relation between myocardial lesions and vascular changes and the direct toxic effect of CA4DP on cardiomyocytes were discussed. We induced myocardial lesions by administration of CA4DP to rats and evaluated myocardial damage by histopathologic examination and electrocardiography. We evaluated blood pressure (BP) of CA4DP-treated rats and effects of CA4DP on cellular impedance-based contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). The results revealed multifocal myocardial necrosis with a predilection for the interventricular septum and subendocardial regions of the apex of the left ventricular wall, injury of capillaries, morphological change of the ST junction, and QT interval prolongation. The histopathological profile of myocardial lesions suggested that CA4DP induced a lack of myocardial blood flow. CA4DP increased the diastolic BP and showed direct effects on hiPS-CMs. These results suggest that CA4DP induces dysfunction of small arteries and capillaries and has direct toxicity in cardiomyocytes. Therefore, it is thought that CA4DP induced capillary and myocardial injury due to collapse of the microcirculation in the myocardium. Moreover, the direct toxic effect of CA4DP on cardiomyocytes induced myocardial lesions in a coordinated manner. PMID:27559241

  13. Combretastatin A4 disodium phosphate-induced myocardial injury

    PubMed Central

    Tochinai, Ryota; Nagata, Yuriko; Ando, Minoru; Hata, Chie; Suzuki, Tomo; Asakawa, Naoyuki; Yoshizawa, Kazuhiko; Uchida, Kazumi; Kado, Shoichi; Kobayashi, Toshihide; Kaneko, Kimiyuki; Kuwahara, Masayoshi

    2016-01-01

    Histopathological and electrocardiographic features of myocardial lesions induced by combretastatin A4 disodium phosphate (CA4DP) were evaluated, and the relation between myocardial lesions and vascular changes and the direct toxic effect of CA4DP on cardiomyocytes were discussed. We induced myocardial lesions by administration of CA4DP to rats and evaluated myocardial damage by histopathologic examination and electrocardiography. We evaluated blood pressure (BP) of CA4DP-treated rats and effects of CA4DP on cellular impedance-based contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs). The results revealed multifocal myocardial necrosis with a predilection for the interventricular septum and subendocardial regions of the apex of the left ventricular wall, injury of capillaries, morphological change of the ST junction, and QT interval prolongation. The histopathological profile of myocardial lesions suggested that CA4DP induced a lack of myocardial blood flow. CA4DP increased the diastolic BP and showed direct effects on hiPS-CMs. These results suggest that CA4DP induces dysfunction of small arteries and capillaries and has direct toxicity in cardiomyocytes. Therefore, it is thought that CA4DP induced capillary and myocardial injury due to collapse of the microcirculation in the myocardium. Moreover, the direct toxic effect of CA4DP on cardiomyocytes induced myocardial lesions in a coordinated manner.

  14. Shifts in the climate space of temperate cyprinid fishes due to climate change are coupled with altered body sizes and growth rates.

    PubMed

    Ruiz-Navarro, Ana; Gillingham, Phillipa K; Britton, J Robert

    2016-09-01

    Predictions of species responses to climate change often focus on distribution shifts, although responses can also include shifts in body sizes and population demographics. Here, shifts in the distributional ranges ('climate space'), body sizes (as maximum theoretical body sizes, L∞) and growth rates (as rate at which L∞ is reached, K) were predicted for five fishes of the Cyprinidae family in a temperate region over eight climate change projections. Great Britain was the model area, and the model species were Rutilus rutilus, Leuciscus leuciscus, Squalius cephalus, Gobio gobio and Abramis brama. Ensemble models predicted that the species' climate spaces would shift in all modelled projections, with the most drastic changes occurring under high emissions; all range centroids shifted in a north-westerly direction. Predicted climate space expanded for R. rutilus and A. brama, contracted for S. cephalus, and for L. leuciscus and G. gobio, expanded under low-emission scenarios but contracted under high emissions, suggesting the presence of some climate-distribution thresholds. For R. rutilus, A. brama, S. cephalus and G. gobio, shifts in their climate space were coupled with predicted shifts to significantly smaller maximum body sizes and/or faster growth rates, aligning strongly to aspects of temperature-body size theory. These predicted shifts in L∞ and K had considerable consequences for size-at-age per species, suggesting substantial alterations in population age structures and abundances. Thus, when predicting climate change outcomes for species, outputs that couple shifts in climate space with altered body sizes and growth rates provide considerable insights into the population and community consequences, especially for species that cannot easily track their thermal niches. PMID:26824727

  15. Potential alteration of fjordal circulation due to a large floating structure—Numerical investigation with application to Hood Canal basin in Puget Sound

    SciTech Connect

    Khangaonkar, Tarang; Wang, Taiping

    2013-01-02

    Circulation in typical fjords is characterized by a shallow brackish layer at the surface over a deep long and narrow saltwater column. This surface layer is responsible for the outflow of water from the fjord, is easily disrupted by external forces, such as wind, and is influenced by freshwater inflow. In this paper, we postulate that the stability of fjordal circulation may also be vulnerable to impacts from anthropogenic alterations, such as floating structures, that could constrict the mixing and transport in the upper layers of the water column. The potential for alteration of circulation in Hood Canal, a silled-fjord located inside Puget Sound, Washington, has been examined. Using classical analytical treatments along the lines formulated by Hansen and Rattray [1965], Rattray [1967], Dyer [1973] and more recently, MacCready [2004], we develop a solution applicable to a range of estuary classifications varying from a partially mixed estuary regime to classical fjord conditions. Both estuary types exist in the Puget Sound system, and we compare our analytical solution with observed data. The analysis is based on an exponential variation of eddy viscosity with depth, and it has been extended further with modifications of the free surface boundary conditions to develop a solution representing the presence of a floating bridge at the estuary/fjord entrance. The model results show that tidally averaged mean circulation under the influence of such a constraint could reduce by as much as 30 to 50 percent. The overall water quality of fjords and narrow estuaries is dependent on net circulation and flushing. A potential decrease in residual flow or a corresponding increase in residence time of this magnitude merits further study.

  16. Myocardial Bridging: An Up-to-Date Review.

    PubMed

    Lee, Michael S; Chen, Cheng-Han

    2015-11-01

    Myocardial bridging is a congenital anomaly in which a segment of a coronary artery takes a "tunneled" intramuscular course under a "bridge" of overlying myocardium. This causes vessel compression in systole, resulting in hemodynamic changes that may be associated with angina, myocardial ischemia, acute coronary syndrome, left ventricular dysfunction, arrhythmias, and even sudden cardiac death. While described on autopsy for centuries, technological advances such as coronary computed tomography angiography and intravascular ultrasound have contributed greatly to our understanding of the anatomic, hemodynamic, and pathophysiological consequences of systolic compression. Atherosclerosis preferentially develops immediately proximal to the bridged segment, likely due to alterations in shear stress, while the compressed segment itself is often spared. First-line therapy of symptomatic bridging remains medical treatment with beta-blockers and non-dihydropyridine calcium-channel blockers, and nitrates are contraindicated. Surgical myotomy, intracoronary stenting, and coronary artery bypass graft surgery have been used for refractory symptoms, but long-term outcomes remain uncertain. Further research is required to better define the patient population that would derive the greatest benefit from surgical and percutaneous intervention. PMID:25999138

  17. Myocardial Bridging: An Up-to-Date Review

    PubMed Central

    Lee, Michael S.; Chen, Cheng-Han

    2016-01-01

    Myocardial bridging is a congenital anomaly in which a segment of a coronary artery takes a “tunneled” intramuscular course under a “bridge” of overlying myocardium. This causes vessel compression in systole, resulting in hemodynamic changes that may be associated with angina, myocardial ischemia, acute coronary syndrome, left ventricular dysfunction, arrhythmias, and even sudden cardiac death. While described on autopsy for centuries, technological advances such as coronary computed tomography angiography and intravascular ultrasound have contributed greatly to our understanding of the anatomic, hemodynamic, and pathophysiological consequences of systolic compression. Atherosclerosis preferentially develops immediately proximal to the bridged segment, likely due to alterations in shear stress, while the compressed segment itself is often spared. First-line therapy of symptomatic bridging remains medical treatment with beta-blockers and non-dihydropyridine calcium-channel blockers, and nitrates are contraindicated. Surgical myotomy, intracoronary stenting, and coronary artery bypass graft surgery have been used for refractory symptoms, but long-term outcomes remain uncertain. Further research is required to better define the patient population that would derive the greatest benefit from surgical and percutaneous intervention. PMID:25999138

  18. Noninvasive measurement of regional myocardial glucose metabolism by positron emission computed tomography. [Dogs

    SciTech Connect

    Schelbert, H.R.; Phelps, M.E.

    1980-06-01

    While the results of regional myocardial glucose metabolism measurements using positron emission computed tomography (/sup 13/N-ammonia) are promising, their utility and value remains to be determined in man. If this technique can be applied to patients with acute myocardial ischemia or infarction it may permit delineation of regional myocardial segments with altered, yet still active metabolism. Further, it may become possible to evaluate the effects of interventions designed to salvage reversibly injured myocardium by this technique.

  19. Transient myocardial ischaemia after acute myocardial infarction.

    PubMed Central

    Currie, P; Saltissi, S

    1990-01-01

    The prevalence and characteristics of transient myocardial ischaemia were studied in 203 patients with recent acute myocardial infarction by both early (6.4 days) and late (38 days) ambulatory monitoring of the ST segment. Transient ST segment depression was much commoner during late (32% patients) than early (14%) monitoring. Most transient ischaemia (greater than 85% episodes) was silent and 80% of patients had only silent episodes. During late monitoring painful ST depression was accompanied by greater ST depression and tended to occur at a higher heart rate. Late transient ischaemia showed a diurnal distribution, occurred at a higher initial heart rate, and was more often accompanied by a further increase in heart rate than early ischaemia. Thus in the first 2 months after myocardial infarction transient ischaemia became increasingly common and more closely associated with increased myocardial oxygen demand. Because transient ischaemic episodes during early and late ambulatory monitoring have dissimilar characteristics they may also have different pathophysiologies and prognostic implications. PMID:2245108

  20. Mechanisms for altered carnitine content in hypertrophied rat hearts

    SciTech Connect

    Reibel, D.K.; O'Rourke, B.; Foster, K.A.

    1987-03-01

    Carnitine levels are reduced in hypertrophied hearts of rats subjected to aortic constriction (banding) and evaluated in hypertrophied hearts of spontaneously hypertensive rats (SHR). In an attempt to determine the mechanisms for these alterations, L-(/sup 14/C)carnitine transport was examined in isolated perfused hearts. Total carnitine uptake was significantly reduced by approx.20% in hypertrophied hearts of banded rats at all perfusate carnitine concentrations employed. The reduction in total uptake was due to a 40% reduction in carrier-mediated carnitine uptake with no difference in uptake by diffusion. In contrast, carnitine uptake was not altered in isolated hypertrophied hearts of SHR. However, serum carnitine levels were elevated in SHR, which could result in increased myocardial carnitine uptake in vivo. The data suggest that altered carnitine content in hypertrophied hearts of aortic-banded rats is due to an alteration in the carrier-mediated carnitine transport system in the myocardium. However, altered carnitine content in hypertrophied hearts of SHR is not due to a change in the carnitine transport system per se but may rather be due to a change in serum carnitine levels.

  1. Bioenergetic Insufficiencies Due to Metabolic Alterations Regulated by the Inhibitory Receptor PD-1 Are an Early Driver of CD8(+) T Cell Exhaustion.

    PubMed

    Bengsch, Bertram; Johnson, Andy L; Kurachi, Makoto; Odorizzi, Pamela M; Pauken, Kristen E; Attanasio, John; Stelekati, Erietta; McLane, Laura M; Paley, Michael A; Delgoffe, Greg M; Wherry, E John

    2016-08-16

    Dynamic reprogramming of metabolism is essential for T cell effector function and memory formation. However, the regulation of metabolism in exhausted CD8(+) T (Tex) cells is poorly understood. We found that during the first week of chronic lymphocytic choriomeningitis virus (LCMV) infection, before severe dysfunction develops, virus-specific CD8(+) T cells were already unable to match the bioenergetics of effector T cells generated during acute infection. Suppression of T cell bioenergetics involved restricted glucose uptake and use, despite persisting mechanistic target of rapamycin (mTOR) signaling and upregulation of many anabolic pathways. PD-1 regulated early glycolytic and mitochondrial alterations and repressed transcriptional coactivator PGC-1α. Improving bioenergetics by overexpression of PGC-1α enhanced function in developing Tex cells. Therapeutic reinvigoration by anti-PD-L1 reprogrammed metabolism in a subset of Tex cells. These data highlight a key metabolic control event early in exhaustion and suggest that manipulating glycolytic and mitochondrial metabolism might enhance checkpoint blockade outcomes. PMID:27496729

  2. Altered sphingolipid metabolism in multidrug-resistant ovarian cancer cells is due to uncoupling of glycolipid biosynthesis in the Golgi apparatus.

    PubMed

    Veldman, Robert Jan; Klappe, Karin; Hinrichs, John; Hummel, Ina; van der Schaaf, Gieta; Sietsma, Hannie; Kok, Jan Willem

    2002-07-01

    Multidrug-resistant tumor cells display enhanced levels of glucosylceramide. In this study, we investigated how this relates to the overall sphingolipid composition of multidrug-resistant ovarian carcinoma cells and which mechanisms are responsible for adapted sphingolipid metabolism. We found in multidrug-resistant cells substantially lower levels of lactosylceramide and gangliosides in sharp contrast to glucosylceramide, galactosylceramide, and sphingomyelin levels. This indicates a block in the glycolipid biosynthetic pathway at the level of lactosylceramide formation, with concomitant accumulation of glucosylceramide. A series of observations exclude regulation at the enzyme level as the underlying mechanism. First, reduced lactosylceramide formation occurred only in intact resistant cells whereas cell-free activity of lactosylceramide synthase was higher compared with the parental cells. Second, the level of lactosylceramide synthase gene expression was equal in both phenotypes. Third, glucosylceramide synthase (mRNA and protein) expression and activity were equal or lower in resistant cells. Based on the kinetics of sphingolipid metabolism, the observation that brefeldin A does not restore lactosylceramide synthesis, and altered localization of lactosylceramide synthase fused to green fluorescent protein, we conclude that lactosylceramide biosynthesis is highly uncoupled from glucosylceramide biosynthesis in the Golgi apparatus of resistant cells. PMID:12039850

  3. Excitatory synapses are stronger in the hippocampus of Rett syndrome mice due to altered synaptic trafficking of AMPA-type glutamate receptors.

    PubMed

    Li, Wei; Xu, Xin; Pozzo-Miller, Lucas

    2016-03-15

    Deficits in long-term potentiation (LTP) at central excitatory synapses are thought to contribute to cognitive impairments in neurodevelopmental disorders associated with intellectual disability and autism. Using the methyl-CpG-binding protein 2 (Mecp2) knockout (KO) mouse model of Rett syndrome, we show that naïve excitatory synapses onto hippocampal pyramidal neurons of symptomatic mice have all of the hallmarks of potentiated synapses. Stronger Mecp2 KO synapses failed to undergo LTP after either theta-burst afferent stimulation or pairing afferent stimulation with postsynaptic depolarization. On the other hand, basal synaptic strength and LTP were not affected in slices from younger presymptomatic Mecp2 KO mice. Furthermore, spine synapses in pyramidal neurons from symptomatic Mecp2 KO are larger and do not grow in size or incorporate GluA1 subunits after electrical or chemical LTP. Our data suggest that LTP is occluded in Mecp2 KO mice by already potentiated synapses. The higher surface levels of GluA1-containing receptors are consistent with altered expression levels of proteins involved in AMPA receptor trafficking, suggesting previously unidentified targets for therapeutic intervention for Rett syndrome and other MECP2-related disorders. PMID:26929363

  4. Channel widening due to urbanization and a major flood can alter bed particle organization and bed stability in an urban boulder-bed channel

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.; Behrns, K.; Blanchet, Z.; Hankin, E.

    2007-12-01

    The Anacostia River is a tributary of the Potomac River north of Washington D.C. that has become progressively more urbanized in the past 50 years. Bankfull discharge and bankfull width in the Anacostia have increased by 3- 4x in the past 50 years. Nearby watersheds of similar size and geology, but without significant urbanization, contain threshold gravel-bed streams. The Anacostia, however, is not a threshold channel; it exhibits break-up of boulder-bed channels in upstream reaches and significant gravel bar formation in downstream reaches. These gravel bars have grown and migrated considerably in the past 10-15 years, contributing significantly to local channel widening that can be twice that of adjacent reaches. The purpose of this study is to determine bedload transport rates and grain size distributions and their relationship to discharge, bed organization and sediment supply. Bed mobility data come from both bedload transport measurements and measurements of channel bed changes. Channel bed changes were obtained from a) repeated channel cross section surveys, b) surface and subsurface size distributions, and c) bed particle organization measurements (measurements of location of particles within reaches). These measurements were made prior to and after the floods of 2006, which equalled the largest floods on record for most parts of the Anacostia River. In some boulder bed reaches, boulders were removed from the center of the channel and deposited along and on the channel banks. The mid-channel boulders were replaced by sheets of gravel and cobbles, significantly altering the bed mobility of the channels.

  5. Is the atherosclerotic phenotype of preeclamptic placentas due to altered lipoprotein concentrations and placental lipoprotein receptors? Role of a small-for-gestational-age phenotype

    PubMed Central

    Hentschke, Marta R.; Poli-de-Figueiredo, Carlos E.; Pinheiro da Costa, Bartira E.; Kurlak, Lesia O.; Williams, Paula J.; Mistry, Hiten D.

    2013-01-01

    Atherosis of spiral arteries in uteroplacental beds from preeclamptic women resemble those of atherosclerosis, characterized by increased plasma lipids and lipoproteins. We hypothesized that: 1) lipoprotein receptors/transporters in the placenta would be upregulated in preeclampsia, associated with increased maternal and fetal lipoprotein concentrations; and 2) expression of these would be reduced in preeclamptic placentae from women delivering small-for-gestational-age (SGA) infants. Placental biopsies and maternal and umbilical serum samples were taken from 27 normotensive and 24 preeclamptic women. Maternal/umbilical cord serum LDL, HDL, total cholesterol, and triglycerides were measured. Placental mRNA expression of lipoprotein receptors/transporters were quantified using quantitative RT-PCR. Protein localization/expression of LDL receptor-related protein 1 (LRP-1) in the preeclamptic placentae with/without SGA was measured by immunohistochemistry. Placental mRNA expression of all genes except paraoxonase-1 (PON-1), microsomal triglyceride transfer protein (MTTP), and protein disulfide isomerase family A member 2 (PDIA2) were observed. No differences for any lipoprotein receptors/transporters were found between groups; however, in the preeclamptic group placental LRP-1 expression was lower in SGA delivering mothers (n = 7; P = 0.036). LRP-1 protein was localized around fetal vessels and Hofbauer cells. This is the first detailed study of maternal/fetal lipoprotein concentrations and placental lipoprotein receptor mRNA expression in normotensive and preeclamptic pregnancies. These findings do not support a role of altered lipid metabolism in preeclampsia, but may be involved in fetal growth. PMID:23898049

  6. Myocardial infarction and marijuana.

    PubMed

    Charles, R; Holt, S; Kirkham, N

    1979-04-01

    Myocardial infarction in the virtual absence of risk factors occurred in a 25-year old man shortly after smoking a cigarette containing marijuana. Subsequent coronary arteriography was normal. PMID:466984

  7. Experimental myocardial infarction

    PubMed Central

    Kumar, Raj; Joison, Julio; Gilmour, David P.; Molokhia, Farouk A.; Pegg, C. A. S.; Hood, William B.

    1971-01-01

    The hemodynamic effects of tachycardia induced by atrial pacing were investigated in left ventricular failure of acute and healing experimental myocardial infarction in 20 intact, conscious dogs. Myocardial infarction was produced by gradual inflation of a balloon cuff device implanted around the left anterior descending coronary artery 10-15 days prior to the study. 1 hr after acute myocardial infarction, atrial pacing at a rate of 180 beats/min decreased left ventricular end-diastolic pressure from 19 to 8 mm Hg and left atrial pressure from 17 to 12 mm Hg, without change in cardiac output. In the healing phase of myocardial infarction 1 wk later, atrial pacing decreased left ventricular end-diastolic pressure from 17 to 9 mm Hg and increased the cardiac output by 37%. This was accompanied by evidence of peripheral vasodilation. In two dogs with healing anterior wall myocardial infarction, left ventricular failure was enhanced by partial occlusion of the circumflex coronary artery. Both the dogs developed pulmonary edema. Pacing improved left ventricular performance and relieved pulmonary edema in both animals. In six animals propranolol was given after acute infarction, and left ventricular function deteriorated further. However the pacing-induced augmentation of cardiac function was unaltered and, hence, is not mediated by sympathetics. The results show that the spontaneous heart rate in left ventricular failure of experimental canine myocardial infarction may be less than optimal and that maximal cardiac function may be achieved at higher heart rates. Images PMID:4395910

  8. Gsα activity is reduced in erythrocyte membranes of patients with psedohypoparathyroidism due to epigenetic alterations at the GNAS locus.

    PubMed

    Zazo, Celia; Thiele, Susanne; Martín, Cesar; Fernandez-Rebollo, Eduardo; Martinez-Indart, Lorea; Werner, Ralf; Garin, Intza; Hiort, Olaf; Perez de Nanclares, Guiomar

    2011-08-01

    In pseudohypoparathyroidism (PHP), PTH resistance results from impairment of signal transduction of G protein-coupled receptors caused by a deficiency of the Gsα-cAMP signaling cascade due to diminished Gsα activity in maternally imprinted tissues. In PHP-Ia, inactivating mutations of the GNAS gene lead to haploinsufficiency in some tissues with biallelic expression, so in addition to PHP, Albright's hereditary osteodystrophy (AHO) is also present. In PHP-Ib, caused by methylation defects at the GNAS locus, diminished Gsα activity was thought to be limited to maternally imprinted tissues, such as the renal proximal tubule and the thyroid, leading to a lack of AHO. Recently, we demonstrated methylation defects in patients with AHO signs, indicating a connection between epigenetic changes and AHO. Our objective was to determine Gsα activity in erythrocyte membranes in patients with epigenetic defects at the GNAS locus compared to normal controls and patients with inactivating GNAS mutations. Gsα activity and expression, mutation of the GNAS locus, and methylation status were studied in patients with PHP and mild signs of AHO (PHP-Ia: 12; PHP-Ib: 17, of which 8 had some features of AHO). Then, we statistically compared the Gsα activity of the different PHP subtypes. Patients with methylation defects at the GNAS locus show a significant decrease in erythrocyte Gsα activity compared to normal controls (PHP-Ib versus controls, p < .001). This was significantly lower in patients with AHO signs (PHP-Ib + mild-AHO versus PHP-Ib, p < .05). Our research shows that PHP-Ia and PHP-Ib classification is not only overlapped genetically, as reported, but also in terms of Gsα activity. Reduced expression of GNAS due to methylation defects could downregulate Gsα activity in other tissues beyond those described and could also be causative of AHO. PMID:21351142

  9. Molecular and cellular mechanisms of myocardial stunning.

    PubMed

    Bolli, R; Marbán, E

    1999-04-01

    The past two decades have witnessed an explosive growth of knowledge regarding postischemic myocardial dysfunction or myocardial "stunning." The purpose of this review is to summarize current information regarding the pathophysiology and pathogenesis of this phenomenon. Myocardial stunning should not be regarded as a single entity but rather as a "syndrome" that has been observed in a wide variety of experimental settings, which include the following: 1) stunning after a single, completely reversible episode of regional ischemia in vivo; 2) stunning after multiple, completely reversible episodes of regional ischemia in vivo; 3) stunning after a partly reversible episode of regional ischemia in vivo (subendocardial infarction); 4) stunning after global ischemia in vitro; 5) stunning after global ischemia in vivo; and 6) stunning after exercise-induced ischemia (high-flow ischemia). Whether these settings share a common mechanism is unknown. Although the pathogenesis of myocardial stunning has not been definitively established, the two major hypotheses are that it is caused by the generation of oxygen-derived free radicals (oxyradical hypothesis) and by a transient calcium overload (calcium hypothesis) on reperfusion. The final lesion responsible for the contractile depression appears to be a decreased responsiveness of contractile filaments to calcium. Recent evidence suggests that calcium overload may activate calpains, resulting in selective proteolysis of myofibrils; the time required for resynthesis of damaged proteins would explain in part the delayed recovery of function in stunned myocardium. The oxyradical and calcium hypotheses are not mutually exclusive and are likely to represent different facets of the same pathophysiological cascade. For example, increased free radical formation could cause cellular calcium overload, which would damage the contractile apparatus of the myocytes. Free radical generation could also directly alter contractile filaments in a

  10. Value of positive myocardial infarction imaging in coronary care units.

    PubMed Central

    Joseph, S P; Pereira-Prestes, A V; Ell, P J; Donaldson, R; Somerville, W; Emanuel, R W

    1979-01-01

    Positive myocardial imaging was undertaken on 120 unselected patients admitted to a coronary care unit with clinical suspicion of acute myocardial infarction. Multipurpose mobile gamma-cameras were used for serial imaging after administration of 99mtechnetium-labelled imidodiphosphonate, a low-cost radiopharmaceutical that is 97% specific for myocardial necrosis, with myocardial uptake and blood clearance most suitable for myocardial imaging. The sensitivty of detection was 94% for patients whose infarction was unequivocal on the ECG; when the presence of raised enzyme concentrations was also used as a criterion for myocardial necrosis, the overall sensitivity for all 120 patients remained 94%. In 73 patients (61%), whose ECGs were unhelpful or difficult to interpret, scintigraphy allowed infarction to be diagnosed in 11 (15%) and to be excluded in five (7%). In 32 (44%) of this group whose ECGs were totally uninterpretable due to previous myocardial damage or disorders of electrical activation, scintigraphy provided confirmation of a diagnosis that otherwise rested only on whether enzyme concentrations were raised. Myocardial imaging is thus a useful technique that permits more definite diagnosis in patients for whom ECG and enzyme data are uncertain. PMID:761017

  11. Myocardial Noncompaction Presenting With Myocardial Bridge

    PubMed Central

    Shen, Yuechun; Li, Xinchun; Lu, Dongfeng; Xiao, Aiyi; Li, Jun

    2015-01-01

    Abstract Myocardial noncompaction, namly isolated noncompaction of the left ventricular myocardium (NVM), is a rare congenital disease. It can be either seen in the absence of other cardiac anomalies, or associated with other congenital cardiac defects, mostly stenotic lesions of the left ventricular outflow tract. A myocardial bridge (MB) is thought being associated with coronary heart disease, such as coronary spasm, arrhythmia, and so on. The significance of MB in association with other congenital cardiac conditions is unknown. We report a novel case who was presented NVM and MB. A 34-year-old man complained of chest prickling-like pain and dizzy for 1 year. His blood pressure was 110/70 mm Hg. Echocardiograph revealed increased trabeculations below the level of papillary muscle of left ventricle (LV); deep intertrabecular recesses in the endocardial wall of LV particularly in apex free wall; and LV ejection fraction of 57%. A coronary computerized tomography scan showed that part, 38.9 cm, of left descending artery tunnel was surrounding by cardiac muscles rather than resting on top of the myocardium. The therapeutics interventions included lifestyle cares, agents of anti-ischemia and improvement myocardial cell metabolism. The patient was followed up for 2.6 years, and his general condition was stable. This case indicates that NVM can be developed with MB, and the complete diagnosis of NVM and MB should be made by different image studies. PMID:26356695

  12. [Energy metabolism and myocardial function in myocardiodystrophy].

    PubMed

    Temirova, K V; Kurlygina, L A; Zavodskaia, I S; Novikova, N A

    1976-09-01

    A total of 92 patients with chronic tonsilitis and cardiovascular changes were subjected to clinical observations, ECG analysis, potassium and nitroglycerine tests, and studies of the lactic acid level and creatinekinase activity as indces of myocardial metabolism. The examinations were conducted prior to and following tonsillectomy. In a majority of patients a correlation was revealed between the degree of ECG changes and the serum lactic acid level, as well as between the ECG improvement and a reduction of the lactic acid level following tonsillectomy. Three stages of tonsillogenic myocardiodystrophy were distinguished. The obtained data indicate the rationale of the used tests for the evaluation of the myocardial meabolism alterations and of the efficacy of treatment of chronic tonsillitis patients. PMID:1011536

  13. Transient myocardial ischaemia after acute myocardial infarction does not induce ventricular arrhythmias.

    PubMed Central

    Currie, P; Saltissi, S

    1993-01-01

    OBJECTIVE--To see whether transient myocardial ischaemia on ambulatory monitoring after myocardial infarction is associated with ventricular arrhythmias. DESIGN--A prospective study. SETTING--The coronary care unit, general medical wards, and cardiorespiratory department of a major teaching hospital. PATIENTS--203 consecutive patients without specific exclusion criteria admitted with acute myocardial infarction. INTERVENTIONS--24 hour ambulatory electrocardiographic monitoring for ventricular arrhythmias and ST depression both early (mean 6.3 days after infarction, n = 201) and late (mean 38 days, n = 177). MAIN OUTCOME MEASURES--Episodes of myocardial ischaemia were identified during ambulatory monitoring by transient ST depression of > or = 1.0 mm lasting for > or = 30 s. Ventricular arrhythmias were single extrasystoles, couplets, or ventricular tachycardia. RESULTS--All ventricular arrhythmias were significantly more frequent in late than early monitoring. The arrhythmias included couplets (in 83/174 (48%) v 49/200 (25%) of patients, p = 0.0000028) and ventricular tachycardia (29/174 (17%) v 15/199 (8%), p = 0.0064). Patients with ST depression (29 early; 56 late), compared with those without ischaemia, did not experience a significant increase in single extrasystoles, couplets (31% v 23% early; 47% v 48% late), or ventricular tachycardia (3% v 8% early; 18% v 16% late). Even patients with frequent (> or = 3 episodes), and deep (> or = 1.5 mm) or prolonged (> or = 20 min) ST depression had no increase in arrhythmias. CONCLUSIONS--Ventricular arrhythmias after myocardial infarction are not associated with transient myocardial ischaemia during daily activities. This study does not support the belief that to abolish silent ischaemia would reduce the incidence of sudden death due to uncontrollable ventricular arrhythmias after myocardial infarction. PMID:8489860

  14. BEHAVIORAL ALTERATIONS DUE TO DIESEL EXHAUST EXPOSURE

    EPA Science Inventory

    Several experiments examining the effects of diesel exhaust on the behavior of rats are reported. Animals were exposed either as adults or neonates. The spontaneous locomotor activity (SLA), measured in standard running wheel cages, of adult rats exposed for 8 h/day, 7 days/week ...

  15. Obesity does not Lead to Imbalance Between Myocardial Phospholamban Phosphorylation and Dephosphorylation

    PubMed Central

    Freire, Paula Paccielli; Alves, Carlos Augusto Barnabe; de Deus, Adriana Fernandes; Leopoldo, Ana Paula Lima; Leopoldo, André Soares; da Silva, Danielle Cristina Tomaz; de Tomasi, Loreta Casquel; Campos, Dijon Henrique Salomé; Cicogna, Antonio Carlos

    2014-01-01

    Background The activation of the beta-adrenergic system promotes G protein stimulation that, via cyclic adenosine monophosphate (cAMP), alters the structure of protein kinase A (PKA) and leads to phospholamban (PLB) phosphorylation. This protein participates in the system that controls intracellular calcium in muscle cells, and it is the primary regulator of sarcoplasmic reticulum calcium pump activity. In obesity, the beta-adrenergic system is activated by the influence of increased leptin, therefore, resulting in higher myocardial phospholamban phosphorylation via cAMP-PKA. Objective To investigate the involvement of proteins which regulate the degree of PLB phosphorylation due to beta-adrenergic activation in obesity. In the present study, we hypothesized that there is an imbalance between phospholamban phosphorylation and dephosphorylation, with prevalence of protein phosphorylation. Methods Male Wistar rats were randomly distributed into two groups: control (n = 14), fed with normocaloric diet; and obese (n = 13), fed with a cycle of four unsaturated high-fat diets. Obesity was determined by the adiposity index, and protein expressions of phosphatase 1 (PP-1), PKA, PLB, phosphorylated phospholamban at serine16 (PPLB-Ser16) were assessed by Western blot. Results Obesity caused glucose intolerance, hyperinsulinemia, hypertriglyceridemia, hyperleptinemia and did not alter the protein expression of PKA, PP-1, PLB, PPLB-Ser16. Conclusion Obesity does not promote an imbalance between myocardial PLB phosphorylation and dephosphorylation via beta-adrenergic system. PMID:25120084

  16. Bovine myocardial epithelial inclusions.

    PubMed

    Baker, D C; Schmidt, S P; Langheinrich, K A; Cannon, L; Smart, R A

    1993-01-01

    Light microscopic, histochemical, immunohistochemical, and ultrastructural methods were used to examine myocardial epithelial masses in the hearts of ten cattle. The tissues consisted of paraffin-embedded or formalin-fixed samples from eight hearts that were being inspected in slaughter houses and from two hearts from calves that died of septicemia. The ages of the cattle ranged from 4 days to 12 years; the breeds were unspecified for all but one Hereford female and the two Holstein calves; and there were three males, four females, and three steers. The masses in these cases were compared with similar appearing lesions found in other animal species. The lesions in the bovine hearts were single to multiple, well circumscribed, found in the left ventricle wall, and composed of squamous to cuboidal epithelial cells that formed tubular, ductular, and acinar structures with lumens that were void or filled with amorphous protein globules. Electron microscopic examination revealed epithelial cells that had sparse apical microvilli, tight apical intercellular junctions, perinuclear bundles of filaments, and rare cilia. Almost half of the bovine epithelial masses (4/9) had occasional diastase-resistant periodic acid-Schiff-positive granules in their cytoplasm, and few had hyaluronidase-resistant alcian blue-positive granules (2/9) or colloidal iron-positive granules (1/9). All myocardial masses had abundant collagen surrounding the tubular and acinar structures, and 2/9 had elastin fibers as well. None of the myocardial masses had Churukian-Schenk or Fontana Masson's silver staining granules in epithelial cells. Immunohistochemically, all bovine myocardial tumors stained positively for cytokeratin (8/8), and occasional masses stained positively for vimentin (3/8) or carcinoembryonic antigen (3/8). None of the masses stained positively for desmin. The myocardial epithelial tumors most likely represent endodermal rests of tissue misplaced during organogenesis. PMID:7680178

  17. Perioperative Assessment of Myocardial Deformation

    PubMed Central

    Duncan, Andra E.; Alfirevic, Andrej; Sessler, Daniel I.; Popovic, Zoran B.; Thomas, James D.

    2014-01-01

    Evaluation of left ventricular performance improves risk assessment and guides anesthetic decisions. However, the most common echocardiographic measure of myocardial function, the left ventricular ejection fraction (LVEF), has important limitations. LVEF is limited by subjective interpretation which reduces accuracy and reproducibility, and LVEF assesses global function without characterizing regional myocardial abnormalities. An alternative objective echocardiographic measure of myocardial function is thus needed. Myocardial deformation analysis, which performs quantitative assessment of global and regional myocardial function, may be useful for perioperative care of surgical patients. Myocardial deformation analysis evaluates left ventricular mechanics by quantifying strain and strain rate. Strain describes percent change in myocardial length in the longitudinal (from base to apex) and circumferential (encircling the short-axis of the ventricle) direction and change in thickness in the radial direction. Segmental strain describes regional myocardial function. Strain is a negative number when the ventricle shortens longitudinally or circumferentially and is positive with radial thickening. Reference values for normal longitudinal strain from a recent meta-analysis using transthoracic echocardiography are (mean ± SD) −19.7 ± 0.4%, while radial and circumferential strain are 47.3 ± 1.9 and −23.3 ± 0.7%, respectively. The speed of myocardial deformation is also important and is characterized by strain rate. Longitudinal systolic strain rate in healthy subjects averages −1.10 ± 0.16 sec−1. Assessment of myocardial deformation requires consideration of both strain (change in deformation), which correlates with LVEF, and strain rate (speed of deformation), which correlates with rate of rise of left ventricular pressure (dP/dt). Myocardial deformation analysis also evaluates ventricular relaxation, twist, and untwist, providing new and noninvasive methods to

  18. Studies the alterations of biochemical and mineral contents in bone tissue of mus musculus due to aluminum toxicity and the protective action of desferrioxamine and deferiprone by FTIR, ICP-OES, SEM and XRD techniques

    NASA Astrophysics Data System (ADS)

    Sivakumar, S.; Khatiwada, Chandra Prasad; Sivasubramanian, J.

    The present study has attempt to analyze the changes in the biochemical and mineral contents of aluminum intoxicated bone and determine the protective action of desferrioxamine (DFO) and deferiprone (DFP) by using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), inductively coupled plasma optical emission spectroscopy (ICP-OES), and scanning electron microscopy (SEM) techniques for four groups of animals such as control (Group I), aluminum intoxicated (Group II), Al + DFP (Group III) and Al + DFO + DFP (Group IV) treated groups respectively. The FTIR spectra of the aluminum intoxicated bone showed significant alteration in the biochemical constituents. The bands ratio at I1400/I877 significantly decreased from control to aluminum, but enhanced it by Al + DFP to Al + DFO + DFP treated bone tissue for treatments of 16 weeks. This result suggests that DFO and DFP are the carbonate inhibitor, recovered from chronic growth of bone diseases and pathologies. The alteration of proteins profile indicated by Amide I and Amide II, where peak area values decreased from control to aluminum respectively, but enhanced by treated with DFP (p.o.) and DFO + DFP (i.p.) respectively. The XRD analysis showed a decrease in crystallinity due to aluminum toxicity. Further, the Ca, Mg, and P contents of the aluminum exposed bone were less than those of the control group, and enhanced by treatments with DFO and DFP. The concentrations of trace elements were found by ICP-OES. Therefore, present study suggests that due to aluminum toxicity severe loss of bone minerals, decrease in the biochemical constituents and changes in the surface morphology.

  19. Diagnostic approaches for diabetic cardiomyopathy and myocardial fibrosis

    PubMed Central

    Maya, Lisandro; Villarreal, Francisco J.

    2009-01-01

    In diabetes mellitus, alterations in cardiac structure/function in the absence of ischemic heart disease, hypertension or other cardiac pathologies is termed diabetic cardiomyopathy. In the United States, the prevalence of diabetes mellitus continues to rise and the disease currently affects about 8% of the general population. Hence, it is imperative the use of appropriate diagnostic strategies for diabetic cardiomyopathy, which may help correctly identify the disease at early stages and implement suitable corrective therapies. Currently, there is no single diagnostic method for the identification of diabetic cardiomyopathy. Diabetic cardiomyopathy is known to induce changes in cardiac structure such as, myocardial hypertrophy, fibrosis and fat droplet deposition. Early changes in cardiac function are typically manifested as abnormal diastolic function that with time leads to loss of contractile function. Echocardiography based methods currently stands as the preferred diagnostic approach for diabetic cardiomyopathy, due to its wide availability and economical use. In addition to conventional techniques, magnetic resonance imaging and spectroscopy along with contrast agents are now leading new approaches in the diagnosis of myocardial fibrosis, and cardiac and hepatic metabolic changes. These strategies can be complemented with serum biomarkers so they can offer a clear picture as to diabetes-induced changes in cardiac structure/function even at very early stages of the disease. This review article intends to provide a summary of experimental and routine tools currently available to diagnose diabetic cardiomyopathy induced changes in cardiac structure/function. These tools can be reliably used in either experimental models of diabetes or for clinical applications. PMID:19595694

  20. Acute myocardial infarction and sudden death in Sioux Indians.

    PubMed Central

    Hrabovsky, S L; Welty, T K; Coulehan, J L

    1989-01-01

    While some Indian tribes have low rates of acute myocardial infarction, Northern Plains Indians, including the Sioux, have rates of morbidity and mortality from acute myocardial infarction higher than those reported for the United States population in general. In a review of diagnosed cases of acute myocardial infarction over a 3-year period in 2 hospitals serving predominantly Sioux Indians, 8% of cases were found misclassified, and 22% failed to meet rigorous diagnostic criteria, although the patients did indeed have ischemic heart disease. Patients had high frequencies of complications and risk factors and a fatality rate of 16% within a month of admission. Sudden deaths likely due to ischemic heart disease but in persons not diagnosed as having acute myocardial infarction by chart review occurred 3 times more frequently than deaths occurring within a month of clinical diagnosis. PMID:2735047

  1. Acute myocardial infarction.

    PubMed

    Rischpler, Christoph

    2016-09-01

    Inflammatory processes after myocardial infarction have gained major interest in recent cardiovascular research. It is believed that not only the degree of cell recruitment to the heart plays a pivotal role in the quality of wound healing after myocardial infarction, but also the balance between different types or even subtypes of cells. It is also this balance which is thought to control key processes in tissue repair, such as apoptosis and neoangiogenesis. In this paper, we aim to review imaging strategies (with a special focus on nuclear molecular imaging strategies) that target cells and processes involved in postischemic inflammation and that have a high potential to be translated into clinic or that are already being used and evaluated in humans. PMID:27225319

  2. [Mortality of myocardial infarction].

    PubMed

    Bonnefoy, E; Kirkorian, G

    2011-12-01

    Coronary disease is a major cause of death and disability. From 1975 to 2000, coronary mortality was reduced by half. Better treatments and reduction of risk factors are the main causes. This phenomenon is observed in most developed countries, but mortality from coronary heart disease continues to increase in developing countries. In-hospital mortality of ST elevation myocardial infarction (STEMI) is in the range of 7 to 10% in registries. In infarction without ST segment elevation (NSTEMI), in-hospital mortality is around 5%. More recent studies found a similar in-hospital mortality for STEMI and NSTEMI. Because of patient selection and monitoring, mortality in clinical trials is much lower. After adjustment for the extent of coronary disease, age, risk factors, history of myocardial infarction, the excess mortality observed in women is fading. Many clinical, biological and laboratory parameters are associated with mortality in myocardial infarction. They refer to the immediate risk of death (ventricular rhythm disturbances, shock…), the extent of infarction (number of leads with ST elevation on the ECG, release of biomarkers, ejection fraction…), the presence of heart failure, the failure of reperfusion and the patient's baseline risk (age, renal function…). Risk scores, and more specifically the GRACE risk score, synthesize these different markers to predict the risk of death in a given patient. However, their use for the treatment of myocardial only concerns NSTEMI. Only a limited number of mechanical or pharmacological interventions reduces mortality of heart attack. The main benefits are observed with reperfusion by thrombolysis or primary angioplasty in STEMI, aspirin, heparin, beta-blockers, angiotensin converting enzyme inhibitors. Some medications such as bivalirudin and fondaparinux reduce mortality by decreasing the incidence of hemorrhagic complications. The guidelines classify interventions according to their benefit and especially their ability

  3. Early manifestation of alteration in cardiac function in dystrophin deficient mdx mouse using 3D CMR tagging

    PubMed Central

    Li, Wei; Liu, Wei; Zhong, Jia; Yu, Xin

    2009-01-01

    Background Duchenne muscular dystrophy (DMD) is caused by the absence of the cytoskeletal protein, dystrophin. In DMD patients, dilated cardiomyopathy leading to heart failure may occur during adolescence. However, early cardiac dysfunction is frequently undetected due to physical inactivity and generalized debilitation. The objective of this study is to determine the time course of cardiac functional alterations in mdx mouse, a mouse model of DMD, by evaluating regional ventricular function with CMR tagging. Methods In vivo myocardial function was evaluated by 3D CMR tagging in mdx mice at early (2 months), middle (7 months) and late (10 months) stages of disease development. Global cardiac function, regional myocardial wall strains, and ventricular torsion were quantified. Myocardial lesions were assessed with Masson's trichrome staining. Results Global contractile indexes were similar between mdx and C57BL/6 mice in each age group. Histology analysis showed that young mdx mice were free of myocardial lesions. Interstitial fibrosis was present in 7 month mdx mice, with further development into patches or transmural lesions at 10 months of age. As a result, 10 month mdx mice showed significantly reduced regional strain and torsion. However, young mdx mice showed an unexpected increase in regional strain and torsion, while 7 month mdx mice displayed similar regional ventricular function as the controls. Conclusion Despite normal global ventricular function, CMR tagging detected a biphasic change in myocardial wall strain and torsion, with an initial increase at young age followed by progressive decrease at older ages. These results suggest that CMR tagging can provide more sensitive measures of functional alterations than global functional indexes in dystrophin-related cardiomyopathies. PMID:19849858

  4. Hearts deficient in both Mfn1 and Mfn2 are protected against acute myocardial infarction.

    PubMed

    Hall, A R; Burke, N; Dongworth, R K; Kalkhoran, S B; Dyson, A; Vicencio, J M; Dorn Ii, G W; Yellon, D M; Hausenloy, D J

    2016-01-01

    Mitochondria alter their shape by undergoing cycles of fusion and fission. Changes in mitochondrial morphology impact on the cellular response to stress, and their interactions with other organelles such as the sarcoplasmic reticulum (SR). Inhibiting mitochondrial fission can protect the heart against acute ischemia/reperfusion (I/R) injury. However, the role of the mitochondrial fusion proteins, Mfn1 and Mfn2, in the response of the adult heart to acute I/R injury is not clear, and is investigated in this study. To determine the effect of combined Mfn1/Mfn2 ablation on the susceptibility to acute myocardial I/R injury, cardiac-specific ablation of both Mfn1 and Mfn2 (DKO) was initiated in mice aged 4-6 weeks, leading to knockout of both these proteins in 8-10-week-old animals. This resulted in fragmented mitochondria (electron microscopy), decreased mitochondrial respiratory function (respirometry), and impaired myocardial contractile function (echocardiography). In DKO mice subjected to in vivo regional myocardial ischemia (30 min) followed by 24 h reperfusion, myocardial infarct size (IS, expressed as a % of the area-at-risk) was reduced by 46% compared with wild-type (WT) hearts. In addition, mitochondria from DKO animals had decreased MPTP opening susceptibility (assessed by Ca(2+)-induced mitochondrial swelling), compared with WT hearts. Mfn2 is a key mediator of mitochondrial/SR tethering, and accordingly, the loss of Mfn2 in DKO hearts reduced the number of interactions measured between these organelles (quantified by proximal ligation assay), attenuated mitochondrial calcium overload (Rhod2 confocal microscopy), and decreased reactive oxygen species production (DCF confocal microscopy) in response to acute I/R injury. No differences in isolated mitochondrial ROS emissions (Amplex Red) were detected in response to Ca(2+) and Antimycin A, further implicating disruption of mitochondria/SR tethering as the protective mechanism. In summary, despite apparent

  5. Hearts deficient in both Mfn1 and Mfn2 are protected against acute myocardial infarction

    PubMed Central

    Hall, A R; Burke, N; Dongworth, R K; Kalkhoran, S B; Dyson, A; Vicencio, J M; Dorn II, G W; Yellon, D M; Hausenloy, D J

    2016-01-01

    Mitochondria alter their shape by undergoing cycles of fusion and fission. Changes in mitochondrial morphology impact on the cellular response to stress, and their interactions with other organelles such as the sarcoplasmic reticulum (SR). Inhibiting mitochondrial fission can protect the heart against acute ischemia/reperfusion (I/R) injury. However, the role of the mitochondrial fusion proteins, Mfn1 and Mfn2, in the response of the adult heart to acute I/R injury is not clear, and is investigated in this study. To determine the effect of combined Mfn1/Mfn2 ablation on the susceptibility to acute myocardial I/R injury, cardiac-specific ablation of both Mfn1 and Mfn2 (DKO) was initiated in mice aged 4–6 weeks, leading to knockout of both these proteins in 8–10-week-old animals. This resulted in fragmented mitochondria (electron microscopy), decreased mitochondrial respiratory function (respirometry), and impaired myocardial contractile function (echocardiography). In DKO mice subjected to in vivo regional myocardial ischemia (30 min) followed by 24 h reperfusion, myocardial infarct size (IS, expressed as a % of the area-at-risk) was reduced by 46% compared with wild-type (WT) hearts. In addition, mitochondria from DKO animals had decreased MPTP opening susceptibility (assessed by Ca2+-induced mitochondrial swelling), compared with WT hearts. Mfn2 is a key mediator of mitochondrial/SR tethering, and accordingly, the loss of Mfn2 in DKO hearts reduced the number of interactions measured between these organelles (quantified by proximal ligation assay), attenuated mitochondrial calcium overload (Rhod2 confocal microscopy), and decreased reactive oxygen species production (DCF confocal microscopy) in response to acute I/R injury. No differences in isolated mitochondrial ROS emissions (Amplex Red) were detected in response to Ca2+ and Antimycin A, further implicating disruption of mitochondria/SR tethering as the protective mechanism. In summary, despite apparent

  6. Cardioprotection against experimental myocardial ischemic injury using cornin

    PubMed Central

    Xu, Y.; Xu, Y.; Luan, H.; Jiang, Y.; Tian, X.; Zhang, S.

    2016-01-01

    Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt. PMID:26871971

  7. Cardioprotection against experimental myocardial ischemic injury using cornin.

    PubMed

    Xu, Y; Xu, Y; Luan, H; Jiang, Y; Tian, X; Zhang, S

    2016-02-01

    Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB) has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R) injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM) blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv) protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt. PMID:26871971

  8. Quantitation of myocardial fatty acid metabolism using PET

    SciTech Connect

    Bergmann, S.R.; Weinheimer, C.J.; Markham, J.; Herrero, P.

    1996-10-01

    Abnormalities of fatty acid metabolism in the heart presage contractile dysfunction and arrhythmias. This study was performed to determine whether myocardial fatty acid metabolism could be quantified noninvasively using PET and 1-{sup 11}C-palmitate. Anesthetized dogs were studied during control conditions; during administration of dobutamine; after oxfenicine; and during infusion of glucose. Dynamic PET data after administration of 1-{sup 11}C-palmitate were fitted to a four-compartment mathematical model. Modeled rates of palmitate utilization correlated closely with directly measured myocardial palmitate and total long-chain fatty acid utilization (r = 0.93 and 0.96, respectively, p < 0.001 for each) over a wide range of arterial fatty acid levels and altered patterns of myocardial substrate use (fatty acid extraction fraction ranging from 1% to 56%, glucose extraction fraction from 1% to 16% and myocardial fatty acid utilization from 1 to 484 nmole/g/min). The percent of fatty acid undergoing oxidation could also be measured. The results demonstrate the ability to quantify myocardial fatty acid utilization with PET. The approach is readily applicable for the determination of fatty acid metabolism noninvasively in patients. 37 refs., 5 figs., 4 tabs.

  9. Dipyridamole thallium-201 myocardial scintigraphy

    SciTech Connect

    Not Available

    1988-09-01

    Thallium-201 (/sup 201/Tl) myocardial scintigraphy is a sensitive technique for detecting coronary artery disease. Standardized exercise testing is the most common method for inducing myocardial stress for /sup 201/Tl imaging. Unfortunately, a significant number of patients are unable to undergo adequate treadmill or bicycle exercise. In these patients, pharmacologic stress with dipyridamole provides a safe, efficacious, and reliable alternative.

  10. Diurnal variations in myocardial metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heart is challenged by a plethora of extracellular stimuli over the course of a normal day, each of which distinctly influences myocardial contractile function. It is therefore not surprising that myocardial metabolism also oscillates in a time-of-day dependent manner. What is becoming increasin...

  11. Noninvasive estimation of regional myocardial oxygen consumption by positron emission tomography with carbon-11 acetate in patients with myocardial infarction

    SciTech Connect

    Walsh, M.N.; Geltman, E.M.; Brown, M.A.; Henes, C.G.; Weinheimer, C.J.; Sobel, B.E.; Bergmann, S.R. )

    1989-11-01

    We previously demonstrated in experimental studies that myocardial oxygen consumption (MVO2) can be estimated noninvasively with positron emission tomography (PET) from analysis of the myocardial turnover rate constant (k) after administration of carbon-11 (11C) acetate. To determine regional k in healthy human subjects and to estimate alterations in MVO2 accompanying myocardial ischemia, we administered (11C)acetate to five healthy human volunteers and to six patients with myocardial infarction. Extraction of (11C)acetate by the myocardium was avid and clearance from the blood-pool rapid yielding myocardial images of excellent quality. Regional k was homogeneous in myocardium of healthy volunteers (coefficient variation = 11%). In patients, k in regions remote from the area of infarction was not different from values in myocardium of healthy human volunteers (0.061 +/- 0.025 compared with 0.057 +/- 0.008 min-1). In contrast, MVO2 in the center of the infarct region was only 6% of that in remote regions (p less than 0.01). In four patients studied within 48 hr of infarction and again more than seven days after the acute event, regional k and MVO2 did not change. The approach developed should facilitate evaluation of the efficacy of interventions designed to enhance recovery of jeopardized myocardium and permit estimation of regional MVO2 and metabolic reserve underlying cardiac disease of diverse etiologies.

  12. Spiral MR myocardial tagging.

    PubMed

    Ryf, Salome; Kissinger, Kraig V; Spiegel, Marcus A; Börnert, Peter; Manning, Warren J; Boesiger, Peter; Stuber, Matthias

    2004-02-01

    In the present study, complementary spatial modulation of magnetization (CSPAMM) myocardial tagging was extended with an interleaved spiral imaging sequence. The use of a spiral sequence enables the acquisition of grid-tagged images with a tagline distance as low as 4 mm in a single breath-hold. Alternatively, a high temporal resolution of 77 frames per second was obtained with 8-mm grid spacing. Ten healthy adult subjects were studied. With this new approach, high-quality images can be obtained and the tags persist throughout the entire cardiac cycle. PMID:14755646

  13. Assessment of myocardial viability.

    PubMed

    Travin, Mark I; Bergmann, Steven R

    2005-01-01

    The prevalence of left ventricular (LV) dysfunction and resultant congestive heart failure is increasing. Patients with this condition are at high risk for cardiac death and usually have significant limitations in their lifestyles. Although there have been advances in medical therapy resulting in improved survival and well being, the best and most definitive therapy, when appropriate, is revascularization. In the setting of coronary artery disease, accounting for approximately two thirds of cases of congestive heart failure, LV dysfunction often is not the result of irreversible scar but rather caused by impairment in function and energy use of still viable-myocytes, with the opportunity for improved function if coronary blood flow is restored. Patients with LV dysfunction who have viable myocardium are the patients at highest risk because of the potential for ischemia but at the same time benefit most from revascularization. It is important to identify viable myocardium in these patients, and radionuclide myocardial scintigraphy is an excellent tool for this. Single-photon emission computed tomography perfusion scintigraphy, whether using thallium-201, Tc-99m sestamibi, or Tc-99m tetrofosmin, in stress and/or rest protocols, has consistently been shown to be an effective modality for identifying myocardial viability and guiding appropriate management. Metabolic imaging with positron emission tomography radiotracers frequently adds additional information and is a powerful tool for predicting which patients will have an improved outcome from revascularization, including some patients referred instead for cardiac transplantation. Other noninvasive modalities, such as stress echocardiography, also facilitate the assessment of myocardial viability, but there are advantages and disadvantages compared with the nuclear techniques. Nuclear imaging appears to require fewer viable cells for detection, resulting in a higher sensitivity but a lower specificity than stress

  14. Impact of high-fat, low-carbohydrate diet on myocardial substrate oxidation, insulin sensitivity, and cardiac function after ischemia-reperfusion.

    PubMed

    Liu, Jian; Wang, Peipei; Douglas, Samuel L; Tate, Joshua M; Sham, Simon; Lloyd, Steven G

    2016-07-01

    High-fat, low-carbohydrate Diet (HFLCD) impairs the myocardial response to ischemia-reperfusion, but the underlying mechanisms remain elusive. We sought to determine the magnitude of diet-induced alterations in intrinsic properties of the myocardium (including insulin sensitivity and substrate oxidation) and circulating substrate and insulin differences resulting from diet, leading to this impaired response. Rats were fed HFLCD (60% kcal from fat/30% protein/10% carbohydrate) or control diet (CONT) (16%/19%/65%) for 2 wk. Isolated hearts underwent global low-flow ischemia followed by reperfusion (I/R). Carbon-13 NMR spectroscopy was used to determine myocardial substrate TCA cycle entry. Myocardial insulin sensitivity was assessed as dose-response of Akt phosphorylation. There was a significant effect of HFLCD and I/R with both these factors leading to an increase in free fatty acid (FFA) oxidation and a decrease in carbohydrate or ketone oxidation. Following I/R, HFLCD led to decreased ketone and increased FFA oxidation; the recovery of left ventricular (LV) function was decreased in HFLCD and was negatively correlated with FFA oxidation and positively associated with ketone oxidation. HFLCD also resulted in reduced insulin sensitivity. Under physiologic ranges, there were no direct effects of buffer insulin and ketone levels on oxidation of any substrate and recovery of cardiac function after I/R. An insulin-ketone interaction exists for myocardial substrate oxidation characteristics. We conclude that the impaired recovery of function after ischemia-reperfusion with HFLCD is largely due to intrinsic diet effects on myocardial properties, rather than to diet effect on circulating insulin or substrate levels. PMID:27199129

  15. Effect of alpha 1-adrenergic blockade on myocardial blood flow during exercise after myocardial infarction.

    PubMed

    Herzog, C A; Dai, X Z; Bache, R J

    1991-08-01

    The effect of alpha 1-adrenergic blockade with prazosin on myocardial blood flow at rest and during two levels of treadmill exercise was assessed in 16 chronically instrumented dogs 9-14 days after myocardial infarction had been produced by occlusion of the left circumflex coronary artery. During resting conditions prazosin did not alter mean myocardial blood flow or the subendocardial-to-subepicardial flow ratio in either normally perfused or collateral-dependent myocardium. However, during exercise at comparable external work loads and comparable rate-pressure products, prazosin significantly increased blood flow to normally perfused (27% increase at the second level of exercise, P less than 0.001) and collateral-dependent myocardium (35% increase at the second level of exercise, P less than 0.001) compared with control. In addition, prazosin caused a small but significant decrease in the subendocardial-to-subepicardial flow ratio in both normal (1.27 +/- 0.04 to 1.19 +/- 0.04; P less than 0.01) and collateral-dependent myocardium (0.57 +/- 0.11 to 0.52 +/- 0.11; P less than 0.01) compared with control, reflecting a disproportionally greater increase in subepicardial flow in response to alpha 1-adrenergic blockade. These data demonstrate that alpha 1-adrenergic vasoconstriction inhibits coronary vasodilation during exercise, even in areas of collateral-dependent myocardium relatively early after coronary artery occlusion. PMID:1678929

  16. Trauma Induced Myocardial Infarction

    PubMed Central

    Lolay, Georges A.; Abdel-Latef, Ahmed K.

    2016-01-01

    Chest Trauma in athletes is a common health problem. However, myocardial infarction secondary to coronary dissection in the setting of blunt chest trauma is extremely rare. We report a case of acute inferior wall myocardial infarction following blunt chest trauma. A 32-year-old male with no relevant medical problems was transferred to our medical center for retrosternal chest pain after being elbowed in the chest during a soccer game. Few seconds later, he started experiencing sharp retrosternal chest pain that was severe to that point where he called the emergency medical service. Upon arrival to the Trauma department patient was still complaining of chest pain. ECG demonstrated ST segment elevation in the inferior leads with reciprocal changes in the lateral leads all consistent with active ischemia. After rolling out Aortic dissection, patient was loaded with ASA, ticagerlor, heparin and was emergently taken to the cardiac catheterization lab. Coronary angiography demonstrated 100% thrombotic occlusion in the distal right coronary artery with TIMI 0 flow distally. After thrombus aspiration, a focal dissection was noted on the angiogram that was successfully stented. Two days after admission patient was discharged home. Echocardiography prior to discharge showed inferior wall akinesis, normal right ventricular systolic function and normal overall ejection fraction. PMID:26490501

  17. Valsartan after myocardial infarction.

    PubMed

    Güleç, Sadi

    2014-12-01

    One of the important problems of the patients undergoing acute myocardial infarction (MI) is early development of heart failure. It has been revealed in various studies that renin-angiotensin-aldosterone system (RAAS) has a significant role in this process. The studies conducted with angiotensin converting enzyme (ACE) inhibitors have resulted in decreased mortality rate. Another RAAS blocker which was discovered about ten years later than other ACE inhibitors in historical process is angiotensin receptor blockers (ARB) inhibiting the efficiency of angiotensin 2 by binding to angiotensin 1 receptor. Valsartan is one of the molecules of this group, which has higher number of large-scale randomized clinical studies. In this review, following presentation of a general overview on heart failure after acute MI, the efficiency of ARBs in this patient group will be discussed. This discussion will mostly emphasize the construction, outcomes and clinical importance of VALIANT (VALsartan In Acute myocardial iNfarcTion), which is the study on valsartan after acute MI heart failure. PMID:25604205

  18. Mass spectrometry for the measurement of intramyocardial gas tensions: methodology and application to the study of myocardial ischemia.

    PubMed

    Khuri, S F; O'Riordan, J; Flaherty, J T; Brawley, R K; Donahoo, J S; Gott, V L

    1975-01-01

    The methodology for use of the mass spectrometer for the measurement of intramyocardial gas tensions in the canine preparation is described. Baseling studies were carried out initially in 36 animals, and control levels for myocardial oxygen tension and myocardial carbon dioxide tension were 19 mm Hg (S.D. 6 mm Hg) and 43 mm Hg (S.D. 10 mm Hg), respectively. Myocardial oxygen tension was not altered significantly by varying the arterial oxygen tension between 65 and 300 mm Hg. However, myocardial carbon dioxide tension increased linearly with increased arterial carbon dioxide tension. In 15 dogs placed on total cardiopulmonary bypass, a perfusion pressure 40-60 mm lower than the control mean arterial pressure resulted in myocardial ischemia with a decrease in myocardial oxygen tension and an increase in myocardial carbon dioxide tension. A subsequent increase in perfusion pressure to control levels resulted in resolution of ischemia and return of myocardial oxygen and carbon dioxide tensions to their control level. In another series of open-chest dogs on cardiopulmonary bypass, a proximal constriction applied to the left coronary circumflex artery resulted in a marked decrease in myocardial oxygen tensions and a marked increase in myocardial carbon dioxide tensions in the region supplied by the constricted vessel. In yet another series of open-chest dogs, it was found that incremental decreases in coronary flow established by constriction of the circumflex artery resulted in an exponential increase in both myocardial carbon dioxide tensions and ST-segment elevation as determined by a 25-gauge multi-contact plunge electrode placed in the posterior left ventricular wall. It appears that mass spectrometry techniques for evaluating myocardial ischemia have several advantages over myocardial biopsy techniques for assay of ATP and lactate, and also over the technique of coronary sinus lactate determination. PMID:1209001

  19. Computational Modeling of the Effects of Myocardial Infarction on Left Ventricular Hemodynamics

    NASA Astrophysics Data System (ADS)

    Vedula, Vijay; Seo, Jung Hee; Mittal, Rajat; Fortini, Stefania; Querzoli, Giorgio

    2012-11-01

    Most in-vivo and modeling studies on myocardial infarction and ischemia have been directed towards understanding the left ventricular wall mechanics including stress-strain behavior, end systolic pressure-volume correlations, ejection fraction and stroke work. Fewer studies have focused on the alterations in the intraventricular blood flow behavior due to local infarctions. Changes in the motion of the endocardium can cause local circulation and stagnation regions; these increase the blood cell residence time in the left ventricle and may eventually be implicated in thrombus formation. In the present study, we investigate the effects of myocardial infarction on the ventricular hemodynamics in simple models of the left ventricle using an immersed-boundary flow solver. Apart from the Eulerian flow features such as vorticity and velocity flow fields, pressure distribution, shear stress, viscous dissipation and pump work, we also examine the Lagrangian dynamics of the flow to gain insights into the effect of flow dynamics on thrombus formation. The study is preceded by a comprehensive validation study which is based on an in-vitro experimental model of the left ventricle and this study is also described. This research is supported by the U.S. National Science Foundation through (NSF) CDI-Type II grant IOS-1124804. Computational resources for some of the simulations were also provided in part through the NSF grant NSF-OCI-108849.

  20. ECG phenomena: pseudopreexcitation and repolarization disturbances resembling ST-elevation myocardial infarction caused by an intraatrial rhabdomyoma in a newborn.

    PubMed

    Paech, Christian; Gebauer, Roman Antonin

    2014-01-01

    As is known from other reports, a rhabdomyoma or tumor metastasis may alter intracardiac electrical conduction, producing electrical phenomena like pseudopreexcitation or repolarization disturbances resembling ST-elevation myocardial infarction or Brugada's syndrome. We present a newborn with a giant atrial rhabdomyoma and additionally multiple ventricular rhabdomyomas. He presented with several electrocardiogram (ECG) phenomena due to tumor-caused atrial depolarization and repolarization disturbances. Except from the cardiac tumors, the physical status was within normal range. Initial ECG showed a rapid atrial tachycardia with a ventricular rate of 230 bpm, which was terminated by electrical cardioversion. Afterwards, the ECG showed atrial rhythm with frequent atrial premature contractions and deformation of the PR interval with large, broad P waves and loss of discret PR segment, imposing as pseudopreexcitation. The following QRS complex was normal, with seemingly abnormal ventricular repolarization resembeling ST-elevation myocardial infarction. The atrial tumor was resected with consequent vast atrial reconstruction using patch plastic. The ventricular tumors were left without manipulation. After surgery, pseudopreexcitation and repolarization abnormalities vanished entirely and an alternans between sinus rhythm and ectopic atrial rhythm was present. These phenomena were supposably caused by isolated atrial depolarization disturbances due to tumor-caused heterogenous endocardial activation. The seemingly abnormal ventricular repolarization is probably due to repolarization of the atrial mass, superimposed on the ventricular repolarization. Recognizably, the QRS complex before and after surgical resection of the rhabdomyoma is identical, underlining the atrial origin of the repolarization abnormalities before surgery. PMID:23663513

  1. Myocardial perfusion as assessed by thallium-201 scintigraphy during the discontinuation of mechanical ventilation in ventilator-dependent patients

    SciTech Connect

    Hurford, W.E.; Lynch, K.E.; Strauss, H.W.; Lowenstein, E.; Zapol, W.M. )

    1991-06-01

    Patients who cannot be separated from mechanical ventilation (MV) after an episode of acute respiratory failure often have coexisting coronary artery disease. The authors hypothesized that increased left ventricular (LV) wall stress during periods of spontaneous ventilation (SV) could alter myocardial perfusion in these patients. Using thallium-201 (201TI) myocardial scintigraphy, the authors studied the occurrence of myocardial perfusion abnormalities during periods of SV in 15 MV-dependent patients (nine women, six men; aged 71 {plus minus} 7 yr, mean {plus minus} SD). Fourteen of these patients were studied once with 201TI myocardial scintigraphy during intermittent mechanical ventilation (IMV) and again on another day, after at least 10 min of SV through a T-piece. One patient was studied during SV only. Thirteen of 14 of the patients (93%) studied during MV had abnormal patterns of initial myocardial 201TI uptake, but only 1 patient demonstrated redistribution of 201TI on delayed images. The remainder of the abnormalities observed during MV were fixed defects. SV produced significant alterations of myocardial 201TI distribution or transient LV dilation, or both, in 7 of the 15 patients (47%). Four patients demonstrated new regional decreases of LV myocardial thallium concentration with redistribution of the isotope on delayed images. The patient studied only during SV also had myocardial 201TI defects with redistribution. Five patients (3 also having areas of 201TI redistribution) had transient LV dilation during SV.

  2. Immunological results in myocardial diseases.

    PubMed Central

    Bolte, H. D.; Schultheiss, P.

    1978-01-01

    Immunological studies have shown new diagnostically important changes in alcoholic and viral myocarditis, as well as in congestive cardiomyopathy. Increased heart size correlated with the degree of congestive heart failure, as well as with negative immunofluorescence and an increased IgA concentration in the serum. These findings may serve as a diagnostic aid in patients with myocardial disease due to alcohol abuse. Viral heart disease is characterized by a variety of symptoms and nuclear antibodies (IgM) can be of help in the differential diagnosis. Heart muscle tissue of patients with congestive cardiomyopathy preferentially binds IgG and IgA. In addition to the other changes these findings are of diagnostic importance. It seems likely that results similar to those obtained for humoral antibodies in congestive cardiomyopathy will apply in the correlation of the haemodynamic status of the patients. The pathophysiological implication of these findings is not clear at present, but the evolution of congestive cardiomyopathy appears to be associated with binding of immunoglobulin to the myocardium, as well as with humoral antiheart antibodies. PMID:704517

  3. Acute myocardial infarction complicating subarachnoid haemorrhage

    PubMed Central

    van der Velden, L.B.J.; Otterspoor, L.C.; Schultze Kool, L.J.; Biessels, G.J.; Verheugt, F.W.A.

    2009-01-01

    An acute myocardial infarction is a rare complication of a subarachnoid haemorrhage. The combination of these two conditions imposes important treatment dilemmas. We describe two patients with this combination of life-threatening conditions. Patient 1 was treated with emergency percutaneous coronary intervention followed by clipping of the anterior communicating artery aneurysm. Six months after discharge the patient's memory and orientation had almost completely recovered. Patient 2 was treated with aspirin until coiling of the aneurysm could be performed. After successful coiling low-molecular-weight heparin was added. One week later the patient died due to a free wall rupture. (Neth Heart J 2009;17:284-7.19789696) PMID:19789696

  4. An unusual myocardial infarction

    PubMed Central

    Di Michele, Sara; Mirabelli, Francesca; Mankad, Sunil

    2014-01-01

    Summary We present a 74-year-old male with a chondrosarcoma, who presented with chest pain. The history, electrocardiogram (ECG), and biomarkers established the diagnosis of myocardial infarction (MI); angiography did not show coronary atherosclerosis and, both initial transthoracic echocardiogram and chest computed tomography (CT), did not demonstrate any cardiac abnormalities. A second echocardiogram following a routine ECG showed presence of a mass involving the right ventricle and the cardiac apex that was confirmed by chest CT scan. We underline the importance of considering cardiac tumors in the clinical arena of MI management. Learning points Cardiac tumors cause ECG changes similar to ischemic heart diseases.Keep in mind cardiac tumors when performing transthoracic echocardiogram (TTE) in the setting of suspected MI.TTE is the technique of choice in detecting cardiac tumors. PMID:26693309

  5. Masquerades of myocardial infarction.

    PubMed Central

    Bean, W. B.

    1976-01-01

    I summarize these observations in Figure 1. It represents every person in a hypothetical population who has myocardial infarction. A large but unknown number, some believe almost half, never get help. Mobile coronary care units are reducing this group, but so far only a little. When the diagnosis is not understood the disease is not recognized. Then come discovery and popularization. Hereafter masquerades hide some cases and the diagnosis is missed. Somewhere fairly early the diagnostic fad leads to false positive diagnosis. As new techniques are discovered, perfected and mastered, false positive errors and masquerades leading to oversights diminish but still exist. All the skill and technical virtuosity in the world will not be applied if we do not think of the disease. When we think of it, even obscure cases may be resolved easily. PMID:960416

  6. Importance of markers in Tc-99m pyrophosphate myocardial images

    SciTech Connect

    Vasavada, P.J.; Micklos, T.J.; Nishiyama, H.

    1985-02-01

    A false-positive Tc-99m PYP myocardial scan may result due to gastric activity from the breakdown of radiopharmaceuticals and accumulation of Tc-99m pertechnetate in gastric cells. Importance of anatomic landmarks during early blood pool images is emphasized to prevent this error.

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

    PubMed Central

    Cosyns, Bernard; Droogmans, Steven; Hernot, Sophie; Degaillier, Céline; Garbar, Christian; Weytjens, Caroline; Roosens, Bram; Schoors, Danny; Lahoutte, Tony; Franken, Philippe R; Van Camp, Guy

    2008-01-01

    The role of structural and functional abnormalities of small vessels in diabetes cardiomyopathy remains unclear. Myocardial contrast echocardiography allows the quantification of myocardial blood flow at rest and during dipyridamole infusion. The aim of the study was to determine the myocardial blood flow reserve in normal rats compared with Streptozotocin-induced diabetic rats using contrast echocardiography. We prospectively studied 40 Wistar rats. Diabetes was induced by intravenous streptozotocin in 20 rats. All rats underwent baseline and stress (dipyridamole: 20 mg/kg) high power intermittent imaging in short axis view under anaesthesia baseline and after six months. Myocardial blood flow was determined and compared at rest and after dipyridamole in both populations. The myocardial blood flow reserve was calculated and compared in the 2 groups. Parameters of left ventricular function were determined from the M-mode tracings and histological examination was performed in all rats at the end of the study. At six months, myocardial blood flow reserve was significantly lower in diabetic rats compared to controls (3.09 ± 0.98 vs. 1.28 ± 0.67 ml min-1 g-1; p < 0.05). There were also a significant decrease in left ventricular function and a decreased capillary surface area and diameter at histology in the diabetic group. In this animal study, diabetes induced a functional alteration of the coronary microcirculation, as demonstrated by contrast echocardiography, a decrease in capillary density and of the cardiac systolic function. These findings may offer new insights into the underlying mechanisms of diabetes cardiomyopathy. PMID:18764943

  8. Acute myocardial infarction and myocardial ischemia-reperfusion injury: a comparison

    PubMed Central

    Hashmi, Satwat; Al-Salam, Suhail

    2015-01-01

    Myocardial infarction (MI) denotes the death of cardiac myocytes due to extended ischemia. Myocardial reperfusion is the restoration of coronary blood flow after a period of coronary occlusion. Reperfusion has the potential to salvage ischemic myocardium but paradoxically can cause injury, a phenomenon called as ‘reperfusion injury’ (IR). Standard histologic, immunohistochemical and Elisa techniques were used to study the histopathologic, oxidative, apoptotic and inflammatory changes in MI and IR. The IL-6 levels in the LV of the MI group were significantly raised as compared to the IR group (P=0.0008). Plasma IL-6 was also significantly increased in the MI group as compared to the IR group (P=0.031). MI model was also associated with increase in the neutrophil polymorphs number in the infarction related myocardium as compared to the re-perfused myocardium. A significant increase in troponin I level in the MI group as compared to the IR group is also seen (P=0.0001). Our IR model showed enhanced pro-apoptotic mediators like cleaved caspase-3 (P=0.005) and cytochrome c in the myocardium as compared to the MI model. In conclusion, myocardial damage in MI is mainly due to ischemic necrosis and inflammatory mechanisms while apoptosis is the main mechanism of cell death in IR in addition to limited ischemic necrosis. PMID:26464621

  9. 2015 Sensorimotor Risk Standing Review Panel Evidence and Status Review For: the Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Spaceflight

    NASA Technical Reports Server (NTRS)

    Steinberg, Susan

    2015-01-01

    The 2015 Sensorimotor Risk Standing Review Panel (from here on referred to as the SRP) participated in a WebEx/teleconference with members of the Human Health Countermeasures (HHC) Element, representatives from the Human Research Program (HRP), NASA Headquarters, and NASA Research and Education Support Services (NRESS) on December 17, 2015 (list of participants is in Section VI of this report). The SRP reviewed the new Evidence Report for the Risk of Impaired Control of Spacecraft/Associated Systems and Decreased Mobility Due to Vestibular/Sensorimotor Alterations Associated with Spaceflight (from here on referred to as the 2015 Sensorimotor Evidence Report), and also received a status review of the Risk. The opening section of the 2015 Sensorimotor Evidence Report provides written descriptions of various incidents that have occurred during space missions. In most of these incidents, the main underlying contributing factors are not easy to identify unambiguously. For example, in section 1.9, a number of falls occurred while astronauts were walking on the moon. It is not clear to the SRP, however, why they fell. It is only possible to extrapolate from likely specific psychophysical or physiological abnormalities, but how these abnormalities were determined, and how they were directly responsible for the falls is unclear to the SRP. Section 2.1.2 on proprioception is very interesting, but the functional significance of the abnormalities detected is not clear. The SRP sees this as a problem throughout the report: a mapping between the component abnormalities identified and the holistic behaviors that are most relevant, for example, controlling the vehicle, and locomotion during egress, is generally lacking. The SRP thinks the cognitive section is too strongly focused on vestibular functioning. The SRP questions the notion that the main cognitive effects are mainly attributable to reversible vestibular changes induced by spaceflight. The SRP thinks that there can also

  10. Acute myocardial infarction in young adults: causes and management

    PubMed Central

    Osula, S; Bell, G; Hornung, R

    2002-01-01

    The case report in this review illustrates an acute myocardial infarction in a young adult probably due to arterial thrombosis that can be attributed to a hypercoagulable state resulting from the nephrotic syndrome. Although rare, acute myocardial infarction should be considered in young adults presenting with chest pain. A detailed clinical history may help to identify the aetiology, and guide subsequent management, but diagnostic coronary angiography is essential. Careful risk factor modification and treatment of the underlying cause should reduce the incidence of recurrent cardiac events. PMID:11796868

  11. [Painless anterior acute myocardial infarction in a transplanted heart].

    PubMed

    Poyet, R; Capilla, E; Tortat, A V; Brocq, F X; Pons, F; Kerebel, S; Jego, C; Cellarier, G R

    2015-11-01

    Cardiac allograft vasculopathy is the major determinant of long-term survival in patients after heart transplantation. Clinical presentations are congestive heart failure, ventricular arrhythmias and sudden cardiac death. Acute coronary syndrome is a rare presentation of cardiac allograft vasculopathy due to myocardial denervation. We present the case of a 31-year-old patient, who had undergone heart transplantation 6 months earlier and who developed a painless anterior myocardial infarction revealed by syncope. He was successfully treated by percutaneous coronary intervention with drug eluting stent implantation. PMID:26472502

  12. Nitroglycerin Use in Myocardial Infarction Patients: Risks and Benefits

    PubMed Central

    Ferreira, Julio C.B.; Mochly-Rosen, Daria

    2012-01-01

    Acute myocardial infarction and its sequelae are leading causes of morbidity and mortality worldwide. Nitroglycerin remains a first-line treatment for angina pectoris and acute myocardial infarction. Nitroglycerin achieves its benefit by giving rise to nitric oxide, which causes vasodilation and increases blood flow to the myocardium. However, continuous delivery of nitroglycerin results in tolerance, limiting the use of this drug. Nitroglycerin tolerance is due, at least in part, to inactivation of aldehyde dehydrogenase 2 (ALDH2), an enzyme that converts nitroglycerin to the vasodilator, nitric oxide. We have recently found that, in addition to nitroglycerin’s effect on the vasculature, sustained treatment with nitroglycerin negatively affects cardiomyocyte viability following ischemia, thus resulting in increased infarct size in a myocardial infarction model in animals. Co-administration of Alda-1, an activator of ALDH2, with nitroglycerin improves metabolism of reactive aldehyde adducts and prevents the nitroglycerin-induced increase in cardiac dysfunction following myocardial infarction. In this review, we describe the molecular mechanisms associated with the benefits and risks of nitroglycerin administration in myocardial infarction. (167 of 200). PMID:22040938

  13. Amphetamine Containing Dietary Supplements and Acute Myocardial Infarction.

    PubMed

    Perez-Downes, Julio; Hritani, Abdulwahab; Baldeo, Candice; Antoun, Patrick

    2016-01-01

    Weight loss is one of the most researched and marketed topics in American society. Dietary regimens, medications that claim to boost the metabolism, and the constant pressure to fit into society all play a role in our patient's choices regarding new dietary products. One of the products that are well known to suppress appetite and cause weight loss is amphetamines. While these medications suppress appetite, most people are not aware of the detrimental side effects of amphetamines, including hypertension, tachycardia, arrhythmias, and in certain instances acute myocardial infarction. Here we present the uncommon entity of an acute myocardial infarction due to chronic use of an amphetamine containing dietary supplement in conjunction with an exercise regimen. Our case brings to light further awareness regarding use of amphetamines. Clinicians should have a high index of suspicion of use of these substances when young patients with no risk factors for coronary artery disease present with acute arrhythmias, heart failure, and myocardial infarctions. PMID:27516911

  14. PET/CT Imaging in Mouse Models of Myocardial Ischemia

    PubMed Central

    Gargiulo, Sara; Greco, Adelaide; Gramanzini, Matteo; Petretta, Maria Piera; Ferro, Adele; Larobina, Michele; Panico, Mariarosaria; Brunetti, Arturo; Cuocolo, Alberto

    2012-01-01

    Different species have been used to reproduce myocardial infarction models but in the last years mice became the animals of choice for the analysis of several diseases, due to their short life cycle and the possibility of genetic manipulation. Many techniques are currently used for cardiovascular imaging in mice, including X-ray computed tomography (CT), high-resolution ultrasound, magnetic resonance imaging, and nuclear medicine procedures. Cardiac positron emission tomography (PET) allows to examine noninvasively, on a molecular level and with high sensitivity, regional changes in myocardial perfusion, metabolism, apoptosis, inflammation, and gene expression or to measure changes in anatomical and functional parameters in heart diseases. Currently hybrid PET/CT scanners for small laboratory animals are available, where CT adds high-resolution anatomical information. This paper reviews mouse models of myocardial infarction and discusses the applications of dedicated PET/CT systems technology, including animal preparation, anesthesia, radiotracers, and images postprocessing. PMID:22505813

  15. PET/CT imaging in mouse models of myocardial ischemia.

    PubMed

    Gargiulo, Sara; Greco, Adelaide; Gramanzini, Matteo; Petretta, Maria Piera; Ferro, Adele; Larobina, Michele; Panico, Mariarosaria; Brunetti, Arturo; Cuocolo, Alberto

    2012-01-01

    Different species have been used to reproduce myocardial infarction models but in the last years mice became the animals of choice for the analysis of several diseases, due to their short life cycle and the possibility of genetic manipulation. Many techniques are currently used for cardiovascular imaging in mice, including X-ray computed tomography (CT), high-resolution ultrasound, magnetic resonance imaging, and nuclear medicine procedures. Cardiac positron emission tomography (PET) allows to examine noninvasively, on a molecular level and with high sensitivity, regional changes in myocardial perfusion, metabolism, apoptosis, inflammation, and gene expression or to measure changes in anatomical and functional parameters in heart diseases. Currently hybrid PET/CT scanners for small laboratory animals are available, where CT adds high-resolution anatomical information. This paper reviews mouse models of myocardial infarction and discusses the applications of dedicated PET/CT systems technology, including animal preparation, anesthesia, radiotracers, and images postprocessing. PMID:22505813

  16. Amphetamine Containing Dietary Supplements and Acute Myocardial Infarction

    PubMed Central

    Hritani, Abdulwahab; Antoun, Patrick

    2016-01-01

    Weight loss is one of the most researched and marketed topics in American society. Dietary regimens, medications that claim to boost the metabolism, and the constant pressure to fit into society all play a role in our patient's choices regarding new dietary products. One of the products that are well known to suppress appetite and cause weight loss is amphetamines. While these medications suppress appetite, most people are not aware of the detrimental side effects of amphetamines, including hypertension, tachycardia, arrhythmias, and in certain instances acute myocardial infarction. Here we present the uncommon entity of an acute myocardial infarction due to chronic use of an amphetamine containing dietary supplement in conjunction with an exercise regimen. Our case brings to light further awareness regarding use of amphetamines. Clinicians should have a high index of suspicion of use of these substances when young patients with no risk factors for coronary artery disease present with acute arrhythmias, heart failure, and myocardial infarctions. PMID:27516911

  17. Diminished synthesis of subunit a (ATP6) and altered function of ATP synthase and cytochrome c oxidase due to the mtDNA 2 bp microdeletion of TA at positions 9205 and 9206.

    PubMed

    Jesina, Pavel; Tesarová, Markéta; Fornůsková, Daniela; Vojtísková, Alena; Pecina, Petr; Kaplanová, Vilma; Hansíková, Hana; Zeman, Jirí; Houstek, Josef

    2004-11-01

    Dysfunction of mitochondrial ATPase (F1F(o)-ATP synthase) due to missense mutations in ATP6 [mtDNA (mitochondrial DNA)-encoded subunit a] is a frequent cause of severe mitochondrial encephalomyopathies. We have investigated a rare mtDNA mutation, i.e. a 2 bp deletion of TA at positions 9205 and 9206 (9205DeltaTA), which affects the STOP codon of the ATP6 gene and the cleavage site between the RNAs for ATP6 and COX3 (cytochrome c oxidase 3). The mutation was present at increasing load in a three-generation family (in blood: 16%/82%/>98%). In the affected boy with severe encephalopathy, a homoplasmic mutation was present in blood, fibroblasts and muscle. The fibroblasts from the patient showed normal aurovertin-sensitive ATPase hydrolytic activity, a 70% decrease in ATP synthesis and an 85% decrease in COX activity. ADP-stimulated respiration and the ADP-induced decrease in the mitochondrial membrane potential at state 4 were decreased by 50%. The content of subunit a was decreased 10-fold compared with other ATPase subunits, and [35S]-methionine labelling showed a 9-fold decrease in subunit a biosynthesis. The content of COX subunits 1, 4 and 6c was decreased by 30-60%. Northern Blot and quantitative real-time reverse transcription-PCR analysis further demonstrated that the primary ATP6--COX3 transcript is cleaved to the ATP6 and COX3 mRNAs 2-3-fold less efficiently. Structural studies by Blue-Native and two-dimensional electrophoresis revealed an altered pattern of COX assembly and instability of the ATPase complex, which dissociated into subcomplexes. The results indicate that the 9205DeltaTA mutation prevents the synthesis of ATPase subunit a, and causes the formation of incomplete ATPase complexes that are capable of ATP hydrolysis but not ATP synthesis. The mutation also affects the biogenesis of COX, which is present in a decreased amount in cells from affected individuals. PMID:15265003

  18. Diminished synthesis of subunit a (ATP6) and altered function of ATP synthase and cytochrome c oxidase due to the mtDNA 2 bp microdeletion of TA at positions 9205 and 9206

    PubMed Central

    2004-01-01

    Dysfunction of mitochondrial ATPase (F1Fo-ATP synthase) due to missense mutations in ATP6 [mtDNA (mitochondrial DNA)-encoded subunit a] is a frequent cause of severe mitochondrial encephalomyopathies. We have investigated a rare mtDNA mutation, i.e. a 2 bp deletion of TA at positions 9205 and 9206 (9205ΔTA), which affects the STOP codon of the ATP6 gene and the cleavage site between the RNAs for ATP6 and COX3 (cytochrome c oxidase 3). The mutation was present at increasing load in a three-generation family (in blood: 16%/82%/>98%). In the affected boy with severe encephalopathy, a homoplasmic mutation was present in blood, fibroblasts and muscle. The fibroblasts from the patient showed normal aurovertin-sensitive ATPase hydrolytic activity, a 70% decrease in ATP synthesis and an 85% decrease in COX activity. ADP-stimulated respiration and the ADP-induced decrease in the mitochondrial membrane potential at state 4 were decreased by 50%. The content of subunit a was decreased 10-fold compared with other ATPase subunits, and [35S]-methionine labelling showed a 9-fold decrease in subunit a biosynthesis. The content of COX subunits 1, 4 and 6c was decreased by 30–60%. Northern Blot and quantitative real-time reverse transcription–PCR analysis further demonstrated that the primary ATP6 – COX3 transcript is cleaved to the ATP6 and COX3 mRNAs 2–3-fold less efficiently. Structural studies by Blue-Native and two-dimensional electrophoresis revealed an altered pattern of COX assembly and instability of the ATPase complex, which dissociated into subcomplexes. The results indicate that the 9205ΔTA mutation prevents the synthesis of ATPase subunit a, and causes the formation of incomplete ATPase complexes that are capable of ATP hydrolysis but not ATP synthesis. The mutation also affects the biogenesis of COX, which is present in a decreased amount in cells from affected individuals. PMID:15265003

  19. [A comprehensive analysis of incidence of myocardial infarction in Vladikavkaz depending on solar and geomagnetic activity].

    PubMed

    Botoeva, N K; Khetarugova, l G; Rapoport, S I

    2013-01-01

    The data on myocardial infarction morbidity in Vladikavkaz for 2007-2010 were analysed with reference to solar and geomagnetic activity. Time series of morbidity in men and women were constructed and their seasonal constituent was distinguished. It was found that the number of myocardial infarctions increases on day with enhanced geomagnetic activity especially among subjects aged 50-69 years. Regression analysis of the relationship between the number of sunspots and myocardial infarctions yielded the equation of piecewise linear regression showing that 42% of the cases were due to the changes in the number of sunspots. Medium strength negative correlation was found between the number of myocardial infarctions and the recurrence index of Bz-component of the interplanetary magnetic field. It suggests an important role of chaotic dynamics of external factors in the development of myocardial infarction. PMID:25696947

  20. Bronchogenic Carcinoma with Cardiac Invasion Simulating Acute Myocardial Infarction

    PubMed Central

    Das, Anirban; Das, Sibes K.; Pandit, Sudipta; Karmakar, Rathindra Nath

    2016-01-01

    Cardiac metastases in bronchogenic carcinoma may occur due to retrograde lymphatic spread or by hematogenous dissemination of tumour cells, but direct invasion of heart by adjacent malignant lung mass is very uncommon. Pericardium is frequently involved in direct cardiac invasion by adjacent lung cancer. Pericardial effusion, pericarditis, and tamponade are common and life threatening presentation in such cases. But direct invasion of myocardium and endocardium is very uncommon. Left atrial endocardium is most commonly involved in such cases due to anatomical contiguity with pulmonary hilum through pulmonary veins, and in most cases left atrial involvement is asymptomatic. But myocardial compression and invasion by adjacent lung mass may result in myocardial ischemia and may present with retrosternal, oppressive chest pain which clinically may simulate with the acute myocardial infarction (AMI). As a result, it leads to misdiagnosis and delayed diagnosis of lung cancer. Here we report a case of non-small-cell carcinoma of right lung which was presented with asymptomatic invasion in left atrium and retrosternal chest pain simulating AMI due to myocardial compression by adjacent lung mass, in a seventy-four-year-old male smoker. PMID:27042370

  1. Myocardial Salvaging Effects of Berberine in Experimental Diabetes Co-Existing with Myocardial Infarction

    PubMed Central

    Borde, Manjusha K.; Mohanty, Ipseeta Ray; Maheshwari, Ujwala; Deshmukh, Y.A.

    2016-01-01

    Introduction Berberine, an isoquinoline alkaloid isolated from the Berberis aristata, has been shown to display a wide array of pharmacological activities (hypoglycaemic and hypolipidemic). Aim The present study was designed to investigate whether these pharmacological properties translate into the cardioprotective effects of Berberine in the setting of diabetes mellitus. Materials and Methods Necessary approval from the Institutional Animal Ethics Committee was taken for the study. Experimental diabetes was produced with single dose of Streptozotocin (STZ): 45mg/kg ip and myocardial infarction was induced by administering Isoproterenol (ISP): 85mg/kg, sc to rats on 35th & 36th day. After the confirmation of diabetes on 7th day (>200mg/dl), Berberine (100 mg/kg) was administered orally to experimental rats from day 8 and continued for 30 days thereafter. Various anti-diabetic (Glucose, HbA1c), cardioprotective (CPK-MB), metabolic (lipid profile), safety {liver function (SGPT, kidney function (Creatinine)} and histopathological indices of injury were evaluated in Healthy Control, Diabetic Control and Berberine treated groups. Results Administration of STZ-ISP resulted in a significant decrease in body weight (p<0.001), diabetic changes (increase in blood glucose, HbA1c), cardiac injury (leakage of myocardial CPK-MB), altered lipid profile, SGPT, creatinine levels (p<0.001) in the diabetic control group rats as compared to healthy control. Berberine treatment demonstrated significant antidiabetic as well as myocardial salvaging effects as indicated by restoration of blood glucose, HbA1c and CPK-MB levels (p<0.001) compared to diabetic control group. In addition, Berberine favourably modulated the lipid parameters (total cholesterol, triglycerides, HDL, LDL). Subsequent to ISP challenge, histopathological assessment of heart, pancreas and biochemical indices of injury confirmed the cardioprotective effects of Berberine in setting of diabetes. In addition, Berberine

  2. The Chinese version of the Myocardial Infarction Dimensional Assessment Scale (MIDAS): Mokken scaling

    PubMed Central

    2012-01-01

    Background Hierarchical scales are very useful in clinical practice due to their ability to discriminate precisely between individuals, and the original English version of the Myocardial Infarction Dimensional Assessment Scale has been shown to contain a hierarchy of items. The purpose of this study was to analyse a Mandarin Chinese translation of the Myocardial Infarction Dimensional Assessment Scale for a hierarchy of items according to the criteria of Mokken scaling. Data from 180 Chinese participants who completed the Chinese translation of the Myocardial Infarction Dimensional Assessment Scale were analysed using the Mokken Scaling Procedure and the 'R' statistical programme using the diagnostics available in these programmes. Correlation between Mandarin Chinese items and a Chinese translation of the Short Form (36) Health Survey was also analysed. Findings Fifteen items from the Mandarin Chinese Myocardial Infarction Dimensional Assessment Scale were retained in a strong and reliable Mokken scale; invariant item ordering was not evident and the Mokken scaled items of the Chinese Myocardial Infarction Dimensional Assessment Scale correlated with the Short Form (36) Health Survey. Conclusions Items from the Mandarin Chinese Myocardial Infarction Dimensional Assessment Scale form a Mokken scale and this offers further insight into how the items of the Myocardial Infarction Dimensional Assessment Scale relate to the measurement of health-related quality of life people with a myocardial infarction. PMID:22221696

  3. Postmortem mRNA Expression Patterns in Left Ventricular Myocardial Tissues and Their Implications for Forensic Diagnosis of Sudden Cardiac Death

    PubMed Central

    Son, Gi Hoon; Park, Seong Hwan; Kim, Yunmi; Kim, Ji Yeon; Kim, Jin Wook; Chung, Sooyoung; Kim, Yu-Hoon; Kim, Hyun; Hwang, Juck-Joon; Seo, Joong-Seok

    2014-01-01

    Sudden cardiac death (SCD), which is primarily caused by lethal heart disorders resulting in structural and arrhythmogenic abnormalities, is one of the prevalent modes of death in most developed countries. Myocardial ischemia, mainly due to coronary artery disease, is the most common type of heart disease leading to SCD. However, postmortem diagnosis of SCD is frequently complicated by obscure histological evidence. Here, we show that certain mRNA species, namely those encoding hemoglobin A1/2 and B (Hba1/2 and Hbb, respectively) as well as pyruvate dehydrogenase kinase 4 (Pdk4), exhibit distinct postmortem expression patterns in the left ventricular free wall of SCD subjects when compared with their expression patterns in the corresponding tissues from control subjects with non-cardiac causes of death. Hba1/2 and Hbb mRNA expression levels were higher in ischemic SCD cases with acute myocardial infarction or ischemic heart disease without recent infarction, and even in cardiac death subjects without apparent pathological signs of heart injuries, than control subjects. By contrast, Pdk4 mRNA was expressed at lower levels in SCD subjects. In conclusion, we found that altered myocardial Hba1/2, Hbb, and Pdk4 mRNA expression patterns can be employed as molecular signatures of fatal cardiac dysfunction to forensically implicate SCD as the primary cause of death. PMID:24642708

  4. The 1999 Ji-Ji (Taiwan) earthquake as a trigger for acute myocardial infarction.

    PubMed

    Tsai, Ching-Hong; Lung, For-Wey; Wang, Shing-Yaw

    2004-01-01

    The authors evaluated the effect of stress due to the Ji-Ji, Taiwan, earthquake, which occurred at 1:47 a.m. on September 21, 1999, on the onset of acute myocardial infarction in six counties near the earthquake epicenter. The rate of hospitalization due to acute myocardial infarction increased during the 6 weeks after the earthquake, and a significantly higher number of patients were hospitalized with acute myocardial infarction during that period, compared with the same 6-week period in the previous year (99 and 65 patients, respectively). The findings suggest that extreme emotional stress due to the natural disaster, superimposed on the stress of awakening, increased the incidence of acute myocardial infarction in this population. PMID:15546824

  5. Lidocaine Enhances Contractile Function of Ischemic Myocardial Regions in Mouse Model of Sustained Myocardial Ischemia

    PubMed Central

    Kania, Gabriela; Osto, Elena; Jakob, Philipp; Krasniqi, Nazmi; Beck-Schimmer, Beatrice; Blyszczuk, Przemyslaw; Eriksson, Urs

    2016-01-01

    Rationale Perioperative myocardial ischemia is common in high-risk patients. The use of interventional revascularisation or even thrombolysis is limited in this patient subset due to exceedingly high bleeding risks. Blockade of voltage-gated sodium channels (VGSC) with lidocaine had been suggested to reduce infarct size and cardiomyocyte cell death in ischemia/reperfusion models. However, the impact of lidocaine on cardiac function during sustained ischemia still remains unclear. Methods Sustained myocardial ischemia was induced by ligation of the left anterior descending artery in 12–16 weeks old male BALB/c mice. Subcutaneous lidocaine (30 mg/kg) was used to block VGSC. Cardiac function was quantified at baseline and at 72h by conventional and speckle-tracking based echocardiography to allow high-sensitivity in vivo phenotyping. Infarct size and cardiomyocyte cell death were assessed post mortem histologically and indirectly using troponin measurements. Results Ischemia strongly impaired both, global systolic and diastolic function, which were partially rescued in lidocaine treated in mice. No differences regarding infarct size and cardiomyocyte cell death were observed. Mechanistically, and as shown with speckle-tracking analysis, lidocaine specifically improves residual contractility in the ischemic but not in the remote, non-ischemic myocardium. Conclusion VGSC blockade with lidocaine rescues function of ischemic myocardium as a potential bridging to revascularisation in the setting of perioperative myocardial ischemia. PMID:27140425

  6. Experimental myocardial infarction

    PubMed Central

    Hood, William B.; Bianco, Jesus A.; Kumar, Raj; Whiting, Richard B.

    1970-01-01

    Compliance of the infarcted left ventricle was studied in dogs 3-5 days after occlusion of the left anterior descending coronary artery. Compliance was assessed from postmortem pressure-volume curves and from pressure-length measurements (mercury-in-silastic segment length gauges) made both in vivo and postmortem. Postmortem pressure-volume curves showed reduced compliance compared to sham-operated animals. Postmortem pressure-length curves of infarcted and adjacent normal myocardium indicated that the diminished total compliance could be attributed to an increase in stiffness of the infarcted area. This was confirmed by in vivo end-diastolic pressure-length changes produced by transient aortic occlusion. The infarcted area was akinetic, showing neither contraction nor aneurysmal bulging. In addition, anesthetized dogs with infarcts, when compared with sham-operated animals, had similar left ventricular end-diastolic volumes (indicator dilution method), but higher left ventricular end-diastolic pressures. Taken with previous observations, which show that systolic aneurysmal bulging is uniformly present at the onset of ischemia, these results indicate that stiffening of the ischemic myocardium occurs during the first 5 days after infarction, and show that elevation of left ventricular filling pressure does not necessarily signify ventricular dilatation. The results also suggest a mechanism whereby ventricular performance may improve during recovery from acute myocardial infarction. Images PMID:4914678

  7. CAD of myocardial perfusion

    NASA Astrophysics Data System (ADS)

    Storm, Corstiaan J.; Slump, Cornelis H.

    2007-03-01

    Our purpose is in the automated evaluation of the physiological relevance of lesions in coronary angiograms. We aim to extract as much as possible quantitative information about the physiological condition of the heart from standard angiographic image sequences. Coronary angiography is still the gold standard for evaluating and diagnosing coronary abnormalities as it is able to locate precisely the coronary artery lesions. The dimensions of the stenosis can be assessed nowadays successfully with image processing based Quantitative Coronary Angiography (QCA) techniques. Our purpose is to assess the clinical relevance of the pertinent stenosis. We therefore analyze the myocardial perfusion as revealed in standard angiographic image sequences. In a Region-of-Interest (ROI) on the angiogram (without an overlaying major blood vessel) the contrast is measured as a function of time (the so-called time-density curve). The required hyperemic state of exercise is induced artificially by the injection of a vasodilator drug e.g. papaverine. In order to minimize motion artifacts we select based on the recorded ECG signal end-diastolic images in both a basal and a hyperemic run in the same projection to position the ROI. We present the development of the algorithms together with results of a small study of 20 patients which have been catheterized following the standard protocol.

  8. Recombinant human neuregulin-1β is protective against radiation-induced myocardial cell injury.

    PubMed

    Zhou, Qiang; Hu, Wenbing; Fei, Xinxiong; Huang, Xuqun; Chen, Xi; Zhao, Deqing; Huang, Jun; Jiang, Lan; Wang, Gangsheng

    2016-07-01

    The aim of the present study was to investigate the role of recombinant human neuregulin-1β (rhNRG-1β) in the repair of the radiation-induced damage of myocardial cells and the underlying mechanism. Rats were divided into the radiotherapy alone group, the rhNRG-1β group (radiotherapy with rhNRG‑1β treatment) and the Herceptin group (radiotherapy with Herceptin treatment), and their myocardial cells were analyzed. The morphology of the myocardial cells was observed under an optical microscope, and the expression of γ‑H2AX and p53 was analyzed using immunohistochemistry and western blot analysis. Damage to the myocardial cells was identified in the three groups following radiation treatment, which was identified by cell swelling and altered morphology. The integrated optical density values of γ‑H2AX in the radiotherapy alone, rhNRG‑1β and Herceptin groups were 50.96±5.548, 27.63±10.61 and 76.12±2.084, respectively. The OD of the radiotherapy alone group was significantly higher than that of the rhNRG‑1β treated group (P<0.0001), and the value of the Herceptin group was significantly higher than that of the radiotherapy alone group (P<0.0001). The p53 level in the rhNRG‑1β group was less than that of the radiotherapy alone group (P<0.001), and was higher in the Herceptin group compared with the radiotherapy alone group (P<0.0001). Thus, rhNRG‑1β can ameliorate radiotherapy-induced myocardial cell injury, predominantly by enhancing myocardial cell DNA repair, inhibiting cell apoptosis and improving myocardial function. The results of this study in myocardial cells suggest that patients with thoracic cancer may benefit from treatment with rhNRG‑1β for the repair of the radiation-induced damage of myocardial cells. PMID:27150576

  9. Myocardial perfusion imaging for detection of silent myocardial ischemia

    SciTech Connect

    Beller, G.A.

    1988-04-21

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

  10. MYOCARDIAL AKT: THE OMNIPRESENT NEXUS

    PubMed Central

    Sussman, Mark A.; Völkers, Mirko; Fischer, Kimberlee; Bailey, Brandi; Cottage, Christopher T.; Din, Shabana; Gude, Natalie; Avitabile, Daniele; Alvarez, Roberto; Sundararaman, Balaji; Quijada, Pearl; Mason, Matt; Konstandin, Mathias H.; Malhowski, Amy; Cheng, Zhaokang; Khan, Mohsin; McGregor, Michael

    2013-01-01

    One of the greatest examples of integrated signal transduction is revealed by examination of effects mediated by AKT kinase in myocardial biology. Positioned at the intersection of multiple afferent and efferent signals, AKT exemplifies a molecular sensing node that coordinates dynamic responses of the cell in literally every aspect of biological responses. The balanced and nuanced nature of homeostatic signaling is particularly essential within the myocardial context, where regulation of survival, energy production, contractility, and response to pathological stress all flow through the nexus of AKT activation or repression. Equally important, the loss of regulated AKT activity is primarily the cause or consequence of pathological conditions leading to remodeling of the heart and eventual decompensation. This review presents an overview compendium of the complex world of myocardial AKT biology gleaned from more than a decade of research. Summarization of the widespread influence that AKT exerts upon myocardial responses leaves no doubt that the participation of AKT in molecular signaling will need to be reckoned with as a seemingly omnipresent regulator of myocardial molecular biological responses. PMID:21742795