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Sample records for arrhythmias venice 5-8

  1. Arrhythmias

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Arrhythmias KidsHealth > For Teens > Arrhythmias Print A A A ... Treated? When to Call the Doctor What Are Arrhythmias? Arrhythmias are abnormal heartbeats usually caused by an ...

  2. Arrhythmia

    MedlinePlus

    An arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats ... is called bradycardia. The most common type of arrhythmia is atrial fibrillation, which causes an irregular and ...

  3. Arrhythmias

    MedlinePlus Videos and Cool Tools

    A change in the heart's normal electrical conduction system can result in an arrhythmia or irregular heartbeat. An arrhythmia can be an abnormally slow heartbeat, or an abnormally fast heartbeat. In ...

  4. Arrhythmia

    MedlinePlus

    ... from the NHLBI on Twitter. What Is an Arrhythmia? Español An arrhythmia (ah-RITH-me-ah) is a problem with ... rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, ...

  5. Arrhythmia

    MedlinePlus

    ... are some of the types of arrhythmias?Atrial fibrillation: The heart beats too fast and irregularly. This ... or congenital heart failure).Ventricular tachycardia and ventricular fibrillation: The heart beats too fast and may not ...

  6. Venice, Italy

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Four hundred bridges cross the labyrinth of canals that form the 120 islands of Venice, situated in a saltwater lagoon between the mouths of the Po and Piave rivers in northeast Italy. All traffic in the city moves by boat. Venice is connected to the mainland, 4 kilometers (2.5 miles) away, by ferries as well as a causeway for road and rail traffic. The Grand Canal winds through the city for about 3 kilometers (about 2 miles), dividing it into two nearly equal sections. According to tradition, Venice was founded in 452, when the inhabitants of Aquileia, Padua, and several other northern Italian cities took refuge on the islands of the lagoon from the Teutonic tribes invading Italy at that time.

    This image was acquired on December 9, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image Earth for the next 6 years to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER will provide scientists in numerous disciplines with critical information for surface mapping, and monitoring dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    Dr. Anne

  7. About Arrhythmia

    MedlinePlus

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More About Arrhythmia Updated:Oct 26,2016 The term "arrhythmia" refers ... damaged. View an animation of arrhythmia . Types of Arrhythmias Atrial Fibrillation = upper heart chambers contract irregularly Bradycardia = ...

  8. Treating Arrhythmias in Children

    MedlinePlus

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Treating Arrhythmias in Children Updated:Dec 21,2016 Many options ... card This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  9. Medications for Arrhythmia

    MedlinePlus

    ... Disease Venous Thromboembolism Aortic Aneurysm More Medications for Arrhythmia Updated:Dec 21,2016 When taken exactly as ... health. This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  10. Why Arrhythmia Matters

    MedlinePlus

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Why Arrhythmia Matters Updated:Dec 21,2016 When the heart's ... fibrillation. This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  11. Types of Arrhythmia

    MedlinePlus

    ... page from the NHLBI on Twitter. Types of Arrhythmia The four main types of arrhythmia are premature ( ... exercise, or too much caffeine or nicotine. Supraventricular Arrhythmias Supraventricular arrhythmias are tachycardias (fast heart rates) that ...

  12. Common Tests for Arrhythmia

    MedlinePlus

    ... Venous Thromboembolism Aortic Aneurysm More Common Tests for Arrhythmia Updated:Dec 21,2016 Several tests can help ... View an animation of arrhythmia . Common Tests for Arrhythmia Holter monitor (continuous ambulatory electrocardiographic monitor) Suspected arrhythmias ...

  13. Children and Arrhythmia

    MedlinePlus

    ... Disease Venous Thromboembolism Aortic Aneurysm More Children and Arrhythmia Updated:Dec 21,2016 If your child has ... options This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  14. Categories of Arrhythmias

    MedlinePlus

    ... previous page En español Aneurysms and Dissections Angina Arrhythmia Bundle Branch Block Cardiomyopathy Carotid Artery Disease Chronic ... Cardiac Arrest Valve Disease Vulnerable Plaque Categories of Arrhythmias Arrhythmias are generally divided into two categories: ventricular ...

  15. How Are Arrhythmias Diagnosed?

    MedlinePlus

    ... page from the NHLBI on Twitter. How Are Arrhythmias Diagnosed? Arrhythmias can be hard to diagnose, especially the types ... symptoms every once in a while. Doctors diagnose arrhythmias based on medical and family histories, a physical ...

  16. How Are Arrhythmias Treated?

    MedlinePlus

    ... page from the NHLBI on Twitter. How Are Arrhythmias Treated? Common arrhythmia treatments include medicines, medical procedures, and surgery. Your doctor may recommend treatment if your arrhythmia causes serious symptoms, such as dizziness, chest pain, ...

  17. Devices for Arrhythmia

    MedlinePlus

    ... Disease Venous Thromboembolism Aortic Aneurysm More Devices for Arrhythmia Updated:Dec 21,2016 In a medical emergency, ... This content was last reviewed September 2016. Printable Arrhythmia Information Sheets What is Arrhythmia? What is Atrial ...

  18. Arrhythmias (For Parents)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Arrhythmias KidsHealth > For Parents > Arrhythmias Print A A A ... evaluated and treated by a doctor. What Causes Arrhythmias? A unique electrical conduction system in the heart ...

  19. Living with an Arrhythmia

    MedlinePlus

    ... from the NHLBI on Twitter. Living With an Arrhythmia Many arrhythmias are harmless. It's common to have an occasional ... heartbeat or mild palpitations . People who have harmless arrhythmias can live healthy lives. They usually don't ...

  20. Spectrum of Fascicular Arrhythmias.

    PubMed

    Sung, Raphael; Scheinman, Melvin

    2016-09-01

    Fascicular arrhythmias encompass a wide spectrum of ventricular arrhythmias that depend on the specialized conduction system of the right and left ventricles. These arrhythmias include premature ventricular complexes, monomorphic ventricular tachycardia, polymorphic ventricular tachycardia, and ventricular fibrillation. These arrhythmias may be organized by mechanism, including intrafascicular reentry, interfascicular reentry, and focal. Mapping and ablation of the fascicular system can result in high cure rates of debilitating and potentially life-threatening arrhythmias. When approaching these arrhythmias, careful consideration of the structure of the His Purkinje system as well as their electrophysiologic properties may help guide even the most complex of arrhythmias.

  1. Prevention and Treatment of Arrhythmia

    MedlinePlus

    ... Venous Thromboembolism Aortic Aneurysm More Prevention & Treatment of Arrhythmia Updated:Dec 21,2016 Do you need treatment? ... Trials . This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  2. Understand Your Risk for Arrhythmia

    MedlinePlus

    ... Thromboembolism Aortic Aneurysm More Understand Your Risk for Arrhythmia Updated:Dec 21,2016 Expected changes in heart ... spirits.) This content was last reviewed September 2016. Arrhythmia • Home • About Arrhythmia • Why Arrhythmia Matters • Understand Your ...

  3. Cardiac arrhythmias in pregnancy.

    PubMed

    Knotts, Robert J; Garan, Hasan

    2014-08-01

    As more women with repaired congenital heart disease survive to their reproductive years and many other women are delaying pregnancy until later in life, a rising concern is the risk of cardiac arrhythmias during pregnancy. Naturally occurring cardiovascular changes during pregnancy increase the likelihood that a recurrence of a previously experienced cardiac arrhythmia or a de novo arrhythmia will occur. Arrhythmias should be thoroughly investigated to determine if there is a reversible etiology, and risks/benefits of treatment options should be fully explored. We discuss the approach to working up and treating various arrhythmias during pregnancy with attention to fetal and maternal risks as well as treatment of fetal arrhythmias. Acute management in stable patients includes close monitoring and intravenous pharmacologic therapy, while DC cardioversion should be used to terminate arrhythmias in hemodynamically unstable patients. Long-term management may require continued oral antiarrhythmic therapy, with particular attention to fetal safety, to prevent complications associated with arrhythmias.

  4. View of northeastern Italy including Venice

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A near vertical view of northeastern Italy including the Venice (Venezia) area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) infrared photograph taken from the Skylab space station in Earth orbit. The mountainous area is the Dolomite Alps. The most conspicuous stream northeast of Venice is the Piave River. The city near the center of the picture on the Brenta River is Bassano del Grappa. The large city of Padua (Padova) is on the western bank of the Grenta near the clock.

  5. 6 CFR 5.8 - Business information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 6 Domestic Security 1 2012-01-01 2012-01-01 false Business information. 5.8 Section 5.8 Domestic... Freedom of Information Act § 5.8 Business information. (a) In general. Business information obtained by... this section. (b) Definitions. For purposes of this section: (1) Business information means...

  6. 6 CFR 5.8 - Business information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 6 Domestic Security 1 2010-01-01 2010-01-01 false Business information. 5.8 Section 5.8 Domestic... Freedom of Information Act § 5.8 Business information. (a) In general. Business information obtained by... this section. (b) Definitions. For purposes of this section: (1) Business information means...

  7. 6 CFR 5.8 - Business information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 6 Domestic Security 1 2014-01-01 2014-01-01 false Business information. 5.8 Section 5.8 Domestic... Freedom of Information Act § 5.8 Business information. (a) In general. Business information obtained by... this section. (b) Definitions. For purposes of this section: (1) Business information means...

  8. 6 CFR 5.8 - Business information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 6 Domestic Security 1 2013-01-01 2013-01-01 false Business information. 5.8 Section 5.8 Domestic... Freedom of Information Act § 5.8 Business information. (a) In general. Business information obtained by... this section. (b) Definitions. For purposes of this section: (1) Business information means...

  9. 6 CFR 5.8 - Business information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 6 Domestic Security 1 2011-01-01 2011-01-01 false Business information. 5.8 Section 5.8 Domestic... Freedom of Information Act § 5.8 Business information. (a) In general. Business information obtained by... this section. (b) Definitions. For purposes of this section: (1) Business information means...

  10. Arrhythmias in peripartum cardiomyopathy.

    PubMed

    Honigberg, Michael C; Givertz, Michael M

    2015-06-01

    Peripartum cardiomyopathy (PPCM) is a complication of late pregnancy and the early postpartum period characterized by dilated cardiomyopathy and heart failure with reduced ejection fraction. Approximately half of women fail to recover left ventricular function. Standard management of heart failure is indicated, with some exceptions for women who are predelivery or breastfeeding. Atrial and ventricular arrhythmias are reported in PPCM, but the frequency of arrhythmias in this condition is not well characterized. Management of PPCM-associated arrhythmias may include antiarrhythmic drugs, catheter ablation, and wearable or implantable cardioverter-defibrillators. Further research is needed on the prevalence, natural history, and optimal management of arrhythmias in PPCM.

  11. Cyclic Emergence of Venice During The Brunhes

    NASA Astrophysics Data System (ADS)

    Kent, D. V.; Rio, D.; Massari, F.; Kukla, G.; Lanci, L.

    Milankovitch cycle stratigraphy has become an important method of calibrating the geomagnetic polarity time scale in the Neogene. The resulting geochronological con- straints can be used to interpret the timing of sea level changes and the long-term rate of subsidence in the Venice area, which is located at the northern end of the Adri- atic Sea in a foreland setting between the eastern Southern Alps and the Apennines, the venue of the classic magnetostratigraphic work of Bill Lowrie, Walter Alvarez, and their colleagues. For the Venice region, the Pleistocene history of sea-level change was reconstructed using an integrated magnetobiocyclostratigraphy of lithofacies, includ- ing magnetic susceptibility variations, and a published palynofloral analysis of con- tinuously cored sediments in a 950 meter-deep drill core. A reference glacioeustatic curve was obtained by scaling the astronomically-calibrated ODP677/SPECMAP ben- thic oxygen isotope record from Shackleton (1995). A simple Airy compensation model was used to account for the effect of isostatic loading. Following slow sediment accumulation in a deeper-water starved basin during most of the Matuyama reverse polarity chron, the Venice area shoaled rapidly in the early and middle Brunhes normal polarity chron in response to a major phase of deltaic progradation. The initial transition to continental sediments occurred during a promi- nent glacioeustatic low-stand that is likely to be Marine Isotope Stage 12 (~0.43 Ma) but could be as young as MIS 8 (~0.25 Ma). The Venice area oscillated from below sea level during subsequent major glacioeustatic high-stands to becoming increasingly emergent during major low-stands as the basin continued to fill with marine and con- tinental sediments. Some parts of the Venice area are now emergent for the first time during a glacioeustatic high-stand (i.e., MIS 1 or the Holocene). The total long-term subsidence rate estimated from the Venice deep core record is less than 0.5 mm

  12. [Supraventricular arrhythmia: electrocardiographic aspects].

    PubMed

    Bayés de Luna, Antoni

    2016-12-23

    Supraventricular arrhythmias are one of the main causes of medical consultation. They may also be the clinical presentation of various cardiovascular diseases and a marker of sudden death. The correct diagnosis of these arrhythmias could be a challenge. The purpose of this narrative review is to update succinctly on the topic.

  13. Land Subsidence International Symposium held in Venice

    NASA Astrophysics Data System (ADS)

    The Third International Symposium on Land Subsidence was held March 18-25, 1984, in Venice, Italy. Sponsors were the Ground-Water Commission of the International Association of Hydrological Sciences (IAHS), the United Nations Educational, Scientific, and Cultural Organization (UNESCO), the Italian National Research Council (CNR), the Italian Regions of Veneto and Emilia-Romagna, the Italian Municipalities of Venice, Ravenna, and Modena, the Venice Province, and the European Research Office. Cosponsors included the International Association of Hydrogeologists (IAH), the International Society for Soil Mechanics and Foundation Engineering (ISSMFE), and the Association of Geoscientists for International Development (AGID).Organized within the framework of UNESCO's International Hydrological Program, the symposium brought together over 200 international interdisciplinary specialists in the problems of land subsidence due to fluid and mineral withdrawal. Because man's continuing heavy development of groundwater, gas, oil, and minerals is changing the natural regime and thus causing more and more subsiding areas in the world, there had been sufficient new land subsidence occurrence, problems, research, and remedial measures since the 1976 Second International Symposium held in Anaheim, California, to develop a most interesting program of nearly 100 papers from about 30 countries. The program consisted of papers covering case histories of fluid and mineral withdrawal, engineering theory and analysis, karst “sink-hole”-type subsidence, subsidence due to dewatering of organic deposits or due to application of water (hydrocompaction), instrumentation, legal, socioeconomic, and environmental effects of land subsidence, and remedial works.

  14. Overview of fetal arrhythmias

    PubMed Central

    Srinivasan, Shardha; Strasburger, Janette

    2012-01-01

    Purpose of review Though fetal arrhythmias account for a small proportion of referrals to a fetal cardiologist, they may be associated with significant morbidity and mortality. The present review outlines the current literature with regard to the diagnosis and, in brief, some management strategies in fetal arrhythmias. Recent findings Advances in echocardiography have resulted in significant improvements in our ability to elucidate the mechanism of arrhythmia at the bedside. At the same time, fetal magnetocardiography is broadening our understanding of mechanisms of arrhythmia especially as it pertains to ventricular arrhythmias and congenital heart block. It provides a unique window to study electrical properties of the fetal heart, unlike what has been available to date. Recent reports of bedside use of fetal ECG make it a promising new technology. The underlying mechanisms resulting in immune-mediated complete heart block in a small subset of ‘at-risk’ fetuses is under investigation. Summary There have been great strides in noninvasive diagnosis of fetal arrhythmias. However, we still need to improve our knowledge of the electromechanical properties of the fetal heart as well as the mechanisms of arrhythmia to further improve outcomes. Multiinstitutional collaborative studies are needed to help answer some of the questions regarding patient, drug selection and management algorithms. PMID:18781114

  15. [Arrhythmia and sport].

    PubMed

    Saoudi, N; Yaici, K; Zarkane, N; Darmon, J P; Rinaldi, J P; Brunner, P; Ricard, P; Mourou, M Y

    2005-12-01

    Sports arrhythmia has gained wide attention with the mediatization of the death of famous sports stars. Sport strongly modifies the structure of the heart with the development of left ventricular hypertrophy which may be difficult to differentiate from that due to doping. Intense training modifies also the resting electrocardiogram with appearance of signs of left ventricular hypertrophy whereas resting sinus bradycardia and atrioventricular conduction disturbances usually reverts upon exertion. Accordingly, arrhythmia may develop ranging from extrasystoles to atrial fibrillation and even sudden death. Recent data suggest that if benign arrhythmia may be the result of the sole intense training and are reversible, malignant ventricular arrhythmia and sudden death mostly occur in unknown structural heart disease. Hypertrophic cardiomyopathy is amongst the most frequent post mortem diagnosis in this situation. Doping is now present in many sports and further threatens the athlete in the safe practice of sport.

  16. Deposition in St. Mark's Basilica of Venice.

    PubMed

    Morabito, E; Zendri, E; Piazza, R; Ganzerla, R; Montalbani, S; Marcoleoni, E; Bonetto, F; Scandella, A; Barbante, C; Gambaro, A

    2013-04-01

    Atmospheric pollutants may cause damage to monuments and historical buildings. Besides air contaminants, soluble salts are also responsible for stone deterioration and decay in outdoor and indoor monuments. The problem of how to conserve works of arts thus requires a deep knowledge of contaminants' concentration and distribution inside buildings. In this work, water-soluble ions inside St. Mark's Basilica in Venice were studied, with the aim of understanding their principal source and distribution inside the building. With the aid of Fourier transform infrared spectroscopy and scanning electron microscopy analysis, the interaction between ions and surface's material was also investigated. Ion chromatographic analysis of depositions highlighted a large amount of "deteriorating agents" such as sulphates and chlorides. A possible source in the innermost area of the basilica has been found for formates and nitrates. On the contrary, a decrease of chloride, from the entrance to the innermost area, has been found, which indicates that the source is outside the building. It is emphasized that different contaminants behave differently on different material, and the effect of pollution inside churches and monuments is not easy to predict. Wood and brick seem to react differently than stone and mortar to the damaging action of salts and pollutants. The present work should be considered a useful tool for the future preservation of St. Mark's Basilica in Venice.

  17. 5-8 Mathematics Interim Guide.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education and Training, Winnipeg.

    This document contains the revisions to the 5-8 Mathematics curriculum produced for Manitoba (Canada) teachers. It contains an introduction and seven content sections: Problem Solving, Algebra, Data Management, Geometry, Measurement, Number Concepts, and Number Operations. The introduction includes discussion of: rationale, goals, big ideas…

  18. Classroom Music: Grades 5-8.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    The guide was designed to aid administrators and teachers in creating, organizing, and staffing music programs for students in middle schools or grades 5-8 in Oregon. It is presented in four parts. Part I describes the unique features of the middle school. The environment and students are in a period of change, and teachers must have certain…

  19. Autoantibodies and Cardiac Arrhythmias

    PubMed Central

    Lee, Hon-Chi; Huang, Kristin T. L.; Wang, Xiao-Li; Shen, Win-Kuang

    2013-01-01

    Autoimmune diseases are associated with significant morbidity and mortality, afflicting about 5% of the population of the United States. They encompass a wide range of disorders that affect all organs of the human body and have a predilection for women. In the past, autoimmune pathogenesis was not thought to be a major mechanism for cardiovascular disorders, and potential relationships remain understudied. However, accumulating evidence suggests that a number of vascular and cardiac conditions are autoimmune-mediated. Recent studies indicate that autoantibodies play an important role in the development of cardiac arrhythmias, including atrial fibrillation, modulation of autonomic influences on heart rate and rhythm, conduction system abnormalities, and ventricular arrhythmias. This manuscript will review the current evidence for the role of autoantibodies in the development of cardiac arrhythmias. PMID:21740882

  20. Mitochondria and Arrhythmias

    PubMed Central

    Yang, Kai-Chien; Bonini, Marcelo G.; Dudley, Samuel C.

    2014-01-01

    Mitochondria are essential to providing ATP thereby satisfying the energy demand of the incessant electrical activity and contractile action of cardiac muscle. Emerging evidence indicates that mitochondrial dysfunction can adversely impact cardiac electrical functioning by impairing the intracellular ion homeostasis and membrane excitability through reduced ATP production and excessive reactive oxidative species (ROS) generation, resulting in increased propensity to cardiac arrhythmias. In this review, the molecular mechanisms linking mitochondrial dysfunction to cardiac arrhythmias are discussed with an emphasis on the impact of increased mitochondrial ROS on the cardiac ion channels and transporters that are critical to maintaining normal electromechanical functioning of the cardiomyocytes. The potential of using mitochondria-targeted antioxidants as a novel anti-arrhythmia therapy is highlighted. PMID:24713422

  1. [Arrhythmias from swallowing].

    PubMed

    Palazzuoli, V; Mondillo, S; Faglia, S; D'Aprile, N; De Luca, G; Kristodhullu, A; Corba, E

    1992-01-01

    We describe the case of a 51-year old, non cardiopathic patient, with recurrent attacks of supraventricular tachycardia induced by swallowing. In the existing literature we found several descriptions of hypokinetic arrhythmias, easily explained by a mechanism of vagal inhibition. The cases of predominantly hyperkinetic arrhythmias, however, are much less common. In these patients the origin of the disease seems to be due to sympathetic oesophageal fibers and superior and medium cardiac nerves. In the present case, as in the others reported in the literature, the drug of choice seems to be Amiodarone which appears to be the most effective in preventing tachyarrhythmias caused by swallowing.

  2. Flooding and Environmental Challenges for Venice and its Lagoon

    NASA Astrophysics Data System (ADS)

    Fletcher, C. A.; Spencer, T.

    2005-07-01

    Time may be running out for Venice. The frequency of flooding is increasing and Venice is no better protected today than it was in November 1966, when a violent storm surge left the city under 2 metres of floodwater. The environmental future is bleak, with continuing land subsidence, acceleration in the rate of sea level rise and possible changes in storminess in prospect. Surrounding the city is a lagoon ecosystem showing signs of severe environmental degradation. This timely scientific and technical volume synthesises the great volume and diversity of recent interdisciplinary research on Venice and its lagoon. The lessons reported here are relevant not only to Venice but also to all those that live and work under the threat of coastal flooding, including the inhabitants of other great cultural centres, like London and St. Petersburg.

  3. Types of Arrhythmia in Children

    MedlinePlus

    ... Disease Venous Thromboembolism Aortic Aneurysm More Types of Arrhythmia in Children Updated:Dec 21,2016 There are ... put in. Checklist for Parents of Children with Arrhythmias Learn CPR and emergency procedures Parents of all ...

  4. Venice Park landfill: Working with the community

    SciTech Connect

    McAdams, C.L.

    1993-09-01

    Venice Park landfill was one of the first sites to be permitted under Michigan's proposed Public Act 641. PA 641 essentially changed the rules and regulations for landfills from the simple design of digging a hole and filling it. It also upgraded standards to those that are more sophisticated, including liners, leachate collection systems, and gas extraction systems. In 1992, methane gas from the landfill was collected into wells drilled into the trash varying in depth from 30-50 feet in depth. A vacuum pulls the gas from the trash into the wells, then through a piping system. The landfill uses about 80-100 kilowatts in-house. The remainder of the gas is sold to Consumers Power Co. which uses landfill gas to supply power to homes.

  5. Behavioral influences on cardiac arrhythmias.

    PubMed

    Lampert, Rachel

    2016-01-01

    Stress can trigger both ventricular and atrial arrhythmias, as evidenced by epidemiological, clinical, and laboratory studies, through its impact on autonomic activity. Chronic stress also increases vulnerability to arrhythmias. Novel therapies aimed at decreasing the psychological and physiological response to stress may decrease arrhythmia frequency and improve quality of life.

  6. Exercise and Inherited Arrhythmias.

    PubMed

    Cheung, Christopher C; Laksman, Zachary W M; Mellor, Gregory; Sanatani, Shubhayan; Krahn, Andrew D

    2016-04-01

    Sudden cardiac death (SCD) in an apparently healthy individual is a tragedy that prompts a series of investigations to identify the cause of death and to prevent SCD in potentially at-risk family members. Several inherited channelopathies and cardiomyopathies, including long QT syndrome (LQTS), catecholaminergic polymorphic ventricular cardiomyopathy (CPVT), hypertrophic cardiomyopathy (HCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC) are associated with exercise-related SCD. Exercise restriction has been a historical mainstay of therapy for these conditions. Syncope and cardiac arrest occur during exercise in LQTS and CPVT because of ventricular arrhythmias, which are managed with β-blockade and exercise restriction. Exercise may provoke hemodynamic or ischemic changes in HCM, leading to ventricular arrhythmias. ARVC is a disease of the desmosome, whose underlying disease process is accelerated by exercise. On this basis, expert consensus has erred on the side of caution, recommending rigorous exercise restriction for all inherited arrhythmias. With time, as familiarity with inherited arrhythmia conditions has increased and patients with milder forms of disease are diagnosed, practitioners have questioned the historical rigorous restrictions advocated for all. This change has been driven by the fact that these are often children and young adults who wish to lead active lives. Recent evidence suggests a lower risk of exercise-related arrhythmias in treated patients than was previously assumed, including those with previous symptoms managed with an implantable cardioverter-defibrillator. In this review, we emphasize shared decision making, monitored medical therapy, individual and team awareness of precautions and emergency response measures, and a more permissive approach to recreational and competitive exercise.

  7. [Psychosomatic aspects of cardiac arrhythmias].

    PubMed

    Siepmann, Martin; Kirch, Wilhelm

    2010-07-01

    Emotional stress facilitates the occurrence of cardiac arrhythmias including sudden cardiac death. The prevalence of anxiety and depression is increased in cardiac patients as compared to the normal population. The risk of cardiovascular mortality is enhanced in patients suffering from depression. Comorbid anxiety disorders worsen the course of cardiac arrhythmias. Disturbance of neurocardiac regulation with predominance of the sympathetic tone is hypothesized to be causative for this. The emotional reaction to cardiac arrhythmias is differing to a large extent between individuals. Emotional stress may result from coping with treatment of cardiac arrhythmias. Emotional stress and cardiac arrhythmias may influence each other in the sense of a vicious circle. Somatoform cardiac arrhythmias are predominantly of psychogenic origin. Instrumental measures and frequent contacts between physicians and patients may facilitate disease chronification. The present review is dealing with the multifaceted relationships between cardiac arrhythmias and emotional stress. The underlying mechanisms and corresponding treatment modalities are discussed.

  8. Systems biology and cardiac arrhythmias.

    PubMed

    Grace, Andrew A; Roden, Dan M

    2012-10-27

    During the past few years, the development of effective, empirical technologies for treatment of cardiac arrhythmias has exceeded the pace at which detailed knowledge of the underlying biology has accumulated. As a result, although some clinical arrhythmias can be cured with techniques such as catheter ablation, drug treatment and prediction of the risk of sudden death remain fairly primitive. The identification of key candidate genes for monogenic arrhythmia syndromes shows that to bring basic biology to the clinic is a powerful approach. Increasingly sophisticated experimental models and methods of measurement, including stem cell-based models of human cardiac arrhythmias, are being deployed to study how perturbations in several biologic pathways can result in an arrhythmia-prone heart. The biology of arrhythmia is largely quantifiable, which allows for systematic analysis that could transform treatment strategies that are often still empirical into management based on molecular evidence.

  9. Chaos control of cardiac arrhythmias.

    PubMed

    Garfinkel, A; Weiss, J N; Ditto, W L; Spano, M L

    1995-01-01

    Chaos theory has shown that many disordered and erratic phenomena are in fact deterministic, and can be understood causally and controlled. The prospect that cardiac arrhythmias might be instances of deterministic chaos is therefore intriguing. We used a recently developed method of chaos control to stabilize a ouabain-induced arrhythmia in rabbit ventricular tissue in vitro. Extension of these results to clinically significant arrhythmias such as fibrillation will require overcoming the additional obstacles of spatiotemporal complexity.

  10. Computing the residence times in the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Umgiesser, G.; Cucco, A.

    2003-04-01

    The Venice Lagoon is a shallow water body with a total area of about 500 km2. Three inlets govern the water exchanges between the Adriatic Sea and the Venice Lagoon. Water, entering and exiting through these channels during an entire tidal cycle, changes its biogeochemical and physical properties. The aim of this work is to investigate the Venice Lagoon circulation and to quantify the turn over time of the lagoon which mainly influences the water quality of the basin. The study has been carried out with a numerical model. The model computes the main hydrodynamic unknowns on a spatial domain that represents the Venice Lagoon and the Adriatic Sea with a finite element grid. The model considers as open boundary the line of Otranto channel in the southern Adriatic Sea and elsewhere as closed boundary the whole perimeter of the Adriatic Sea and Venice Lagoon. The model has been calibrated using the sea level data measured by more than twelve tide gauges located along the Adriatic Sea and inside the lagoon. The results obtained by the calibrated model have been validated with experimental data such as discharge data collected by botton mounted ADCP probes located at each inlet. The simulations take into account the tidal forcing and the different wind regimes. The instantaneous circulation and the residual current fields have been analyzed and the impact of the most important wind regimes on the circulation has been studied. The turn over time of the lagoon has been computed under different forcing conditions. A passive tracer only subjected to transport mechanism, has been released inside the lagoon. Resolving the time decaying of the tracer concentration for the whole area, the model computes the spatial distribution of the residence time in the basin. The results show that the re-import of water that previously exited the lagoon through the three inlets, plays an important role on the estimation of the turn over time of the lagoon thus influencing the water quality of

  11. Mechanisms of cardiac arrhythmias

    PubMed Central

    Tse, Gary

    2015-01-01

    Blood circulation is the result of the beating of the heart, which provides the mechanical force to pump oxygenated blood to, and deoxygenated blood away from, the peripheral tissues. This depends critically on the preceding electrical activation. Disruptions in the orderly pattern of this propagating cardiac excitation wave can lead to arrhythmias. Understanding of the mechanisms underlying their generation and maintenance requires knowledge of the ionic contributions to the cardiac action potential, which is discussed in the first part of this review. A brief outline of the different classification systems for arrhythmogenesis is then provided, followed by a detailed discussion for each mechanism in turn, highlighting recent advances in this area. PMID:27092186

  12. Who Is at Risk for Arrhythmia?

    MedlinePlus

    ... on Twitter. Who Is at Risk for an Arrhythmia? Arrhythmias are very common in older adults. Atrial fibrillation (a common type of arrhythmia that can cause problems) affects millions of people, ...

  13. Arrhythmias in newborn thoroughbred foals.

    PubMed

    Yamamoto, K; Yasuda, J; Too, K

    1992-05-01

    Foetal electrocardiograms (ECG) were obtained from 39 of 50 Thoroughbred foaling mares close to delivery. The 50 newborn foals were studied electrocardiographically during their adaptive period, immediately after birth. In 48 foals there were paroxysmal arrhythmias or mixed arrhythmias. The most common arrhythmias were sinus arrhythmias including wandering pacemaker (32/50) and atrial premature contraction (30/50). The others observed were atrial fibrillation (15/50), ventricular premature contraction (10/50), partial atrioventricular block (7/50), ventricular tachycardia (4/50), atrial tachycardia (3/50) and idioventricular rhythm (1/50). The duration of the arrhythmias was approximately 5 min, and in all cases the arrhythmia disappeared within 15 min of birth. From foetal ECG recordings, no indication of the likelihood of neonatal arrhythmias was detected. With the exception of 2 cases, all foals have continued to grow and develop normally. These arrhythmias are considered normal physiological processes in newborn Thoroughbred foals during the adaptive period to extra-uterine life. High vagal tone and hypoxaemia at birth are probably the main contributing factors.

  14. Intraoperative management of critical arrhythmia

    PubMed Central

    2017-01-01

    The incidence of intraoperative arrhythmia is extremely high, and some arrhythmias require clinical attention. Therefore, it is essential for the anesthesiologist to evaluate risk factors for arrhythmia and understand their etiology, electrophysiology, diagnosis, and treatment. Anesthetic agents reportedly affect normal cardiac electrical activity. In the normal cardiac cycle, the sinoatrial node initiates cardiac electrical activity through intrinsic autonomous pacemaker activity. Sequential atrial and ventricular contractions result in an effective cardiac pumping mechanism. Arrhythmia occurs due to various causes, and the cardiac pumping mechanism may be affected. A severe case may result in hemodynamic instability. In this situation, the anesthesiologist should eliminate the possible causes of arrhythmia and manage the condition, creating hemodynamic stability under proper electrocardiographic monitoring. PMID:28367281

  15. Case Studies in Censorship: Censoring "The Merchant of Venice."

    ERIC Educational Resources Information Center

    Gray, Richard A.

    1991-01-01

    Reviews censorship of "The Merchant of Venice," which has been based on its portrayal of the Jewish character Shylock. Background information is followed by an annotated bibliography which includes 15 citations dealing with Shylock, 22 citations to articles that address the censorship of the play, and 64 works of literature that have…

  16. Using "The Merchant of Venice" in Teaching Monetary Economics.

    ERIC Educational Resources Information Center

    Kish-Goodling, Donna M.

    1998-01-01

    Uses the theme of usury in Shakespeare's "The Merchant of Venice," and the history of Christian and Jewish beliefs concerning the charging of interest on loans to crystallize lending practices throughout history, particularly the medieval period and the transition to modern capitalism. Outlines themes addressed in the unit and…

  17. A Teacher's Guide for "The Merchant of Venice" and "Othello."

    ERIC Educational Resources Information Center

    WGBH-TV, Boston, MA.

    William Shakespeare has influenced most, if not all, Western playwrights. His techniques, themes, characters, and plots are contained in much of what is produced today, from television to Broadway. This teacher's guide provides summaries of the plays "The Merchant of Venice" and "Othello," essays, and corresponding student…

  18. Tycho Brahe and the Republic of Venice: a failed project

    NASA Astrophysics Data System (ADS)

    Pigatto, Luisa

    In 1592 the Senate of the Republic of Venice issued a decree by which awarded Tycho Brahe `300 coronati' for an astronomical mission to Alexandria in Egypt. The aim was to measure the pole elevation with meridian observations both of Sun and stars. Tycho writes about this project, never carried into execution, in his Astronomiae Instauratae Mechanica of 1598.

  19. 1 CFR 5.8 - Form of citation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Form of citation. 5.8 Section 5.8 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.8 Form of citation. Without prejudice to any other form of citation, Federal Register material may be cited by...

  20. 1 CFR 5.8 - Form of citation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Form of citation. 5.8 Section 5.8 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.8 Form of citation. Without prejudice to any other form of citation, Federal Register material may be cited by...

  1. 1 CFR 5.8 - Form of citation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Form of citation. 5.8 Section 5.8 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER GENERAL § 5.8 Form of citation. Without prejudice to any other form of citation, Federal Register material may be cited by...

  2. Systems Pharmacology of Arrhythmias

    PubMed Central

    Berger, Seth I.; Ma’ayan, Avi; Iyengar, Ravi

    2011-01-01

    Long-QT syndrome (LQTS) is a congenital or drug-induced change in electrical activity of the heart that can lead to fatal arrhythmias. Mutations in 12 genes encoding ion channels and associated proteins are linked with congenital LQTS. With a computational systems biology approach, we found that gene products involved in LQTS formed a distinct functional neighborhood within the human interactome. Other diseases form similarly selective neighborhoods, and comparison of the LQTS neighborhood with other disease-centered neighborhoods suggested a molecular basis for associations between seemingly unrelated diseases that have increased risk of cardiac complications. By combining the LQTS neighborhood with published genome-wide association study data, we identified previously unknown single-nucleotide polymorphisms likely to affect the QT interval. We found that targets of U.S. Food and Drug Administration (FDA)–approved drugs that cause LQTS as an adverse event were enriched in the LQTS neighborhood. With the LQTS neighborhood as a classifier, we predicted drugs likely to have risks for QT effects and we validated these predictions with the FDA’s Adverse Events Reporting System, illustrating how network analysis can enhance the detection of adverse drug effects associated with drugs in clinical use. Thus, the identification of disease-selective neighborhoods within the human interactome can be useful for predicting new gene variants involved in disease, explaining the complexity underlying adverse drug side effects, and predicting adverse event susceptibility for new drugs. PMID:20407125

  3. Data analysis in cardiac arrhythmias.

    PubMed

    Rodrigo, Miguel; Pedrón-Torecilla, Jorge; Hernández, Ismael; Liberos, Alejandro; Climent, Andreu M; Guillem, María S

    2015-01-01

    Cardiac arrhythmias are an increasingly present in developed countries and represent a major health and economic burden. The occurrence of cardiac arrhythmias is closely linked to the electrical function of the heart. Consequently, the analysis of the electrical signal generated by the heart tissue, either recorded invasively or noninvasively, provides valuable information for the study of cardiac arrhythmias. In this chapter, novel cardiac signal analysis techniques that allow the study and diagnosis of cardiac arrhythmias are described, with emphasis on cardiac mapping which allows for spatiotemporal analysis of cardiac signals.Cardiac mapping can serve as a diagnostic tool by recording cardiac signals either in close contact to the heart tissue or noninvasively from the body surface, and allows the identification of cardiac sites responsible of the development or maintenance of arrhythmias. Cardiac mapping can also be used for research in cardiac arrhythmias in order to understand their mechanisms. For this purpose, both synthetic signals generated by computer simulations and animal experimental models allow for more controlled physiological conditions and complete access to the organ.

  4. [Maternal cardiac arrhythmias in pregnancy].

    PubMed

    Facchini, M; Bauersfeld, U; Fasnacht, M; Candinas, R

    2000-12-23

    During pregnancy an increased incidence of maternal cardiac arrhythmias is observed. These include a wide spectrum, from clinically irrelevant isolated premature beats to debilitating supraventricular and ventricular tachycardias. In principle, management of arrhythmias during pregnancy is similar to that in non-pregnant patients. However, special consideration should be given to foetal age and potential teratogenic and haemodynamic adverse drug effects on the foetus. Therapeutic strategy should be guided by interdisciplinary consulting (i.e. cardiology, obstetrics, neonatology). Diagnostic evaluation must rule out underlying cardiovascular, pulmonary, endocrine or metabolic diseases. Additionally, precipitating factors such as excessive caffeine and/or alcohol ingestion and cigarette smoking should be avoided. For benign arrhythmias a conservative approach is appropriate. Antiarrhythmic drug selection depends on the specific arrhythmia being treated and the cardiac condition of the mother and the foetus. Some antiarrhythmic agents, such as propranolol, metoprolol, digoxin and quinidine, have been extensively tested during pregnancy and have proven to be safe; they should therefore, whenever possible, be used as firstline. For supraventricular tachycardia, intravenous adenosine may be used to terminate the arrhythmia if vagal manoeuvres fail. In emergency situations cardioversion may be performed with relative safety. Implantable cardioverter defibrillators as a preventive measure for life-threatening arrhythmias in pregnant patients do not seem to increase the risk of major complications.

  5. Maternal arrhythmia and perinatal outcomes

    PubMed Central

    Henry, Dana; Gonzalez, Juan M; Harris, Ian, S.; Sparks, Teresa; Killion, Molly; Thiet, Mari-Paule; Bianco, Katherine

    2016-01-01

    Objective To determine if arrhythmia in the setting of maternal cardiac disease (MCD) affects perinatal outcomes. Study Design This is a retrospective cohort study of pregnant women with MCD who delivered from 2008 to 2013. Perinatal outcomes among women with an arrhythmia were compared to those without. Result Among 143 women; 36 (25%) had an arrhythmia. Those with an arrhythmia were more likely to have a spontaneous vaginal delivery (64% vs. 43%, p < 0.05) and required fewer operative vaginal births (8% vs. 27%, p=0.02). Pregnancies were more likely to be complicated by IUGR (17% vs. 5%, p < 0.05) although there were no differences in the rate of small for gestational age. The risk of IUGR remained increased after controlling for confounding (aOR 6.98, 95% CI 1.59–30.79, p=0.01). Two cases of placental abruption were identified among mothers with arrhythmia while none were identified in the controls (p < 0.05) Conclusion Patients with arrhythmias were more likely to have a spontaneous vaginal delivery. Our data suggests that these pregnancies were an increased risk for IUGR. PMID:27309629

  6. 76 FR 60113 - Culturally Significant Objects Imported for Exhibition Determinations: “Masters of Venice...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-28

    ... Paintings of Passion and Power from Kunsthistorisches Museum, Vienna'' SUMMARY: Notice is hereby given of... included in the exhibition ``Masters of Venice: Renaissance Paintings of Passion and Power...

  7. Is the 'mose' project to save Venice already obsolete?

    NASA Astrophysics Data System (ADS)

    Pirazzoli, P. A.; Umgiesser, G.

    2003-04-01

    Five meteorological and surge events that occurred during the last decades are analysed, simulating that a relative sea-level rise of 0.5 m (average IPCC prediction for the year 2100 + local subsidence) has taken place and that the "MOSE" gates (the planned mobile protection against flooding of Venice) could have been in operation during the events. In all cases considered, flooding would have occurred in the lowest parts of Venice, lasting for dozen hours, in spite of raising the street level to the +100 cm, or even to the +110 cm levels above the local datum. Problems would start for a sea-level rise of about 25--30 cm, or even of only 10 cm for a repetition of the 1966 event. This is both because the projected gates are not watertight, and rainfall and river discharge contribute to raise the average water level in the lagoon. Therefore, the "MOSE" would be inadequate to protect Venice in the case of the near-future sea-level rise predicted by climatic models for this century. This project might be useful to attenuate surge peaks, but would not prevent gradual floods when the closure durations implied by a sea-level rise will increase. Temporary "diffuse" interventions seem preferable to the "MOSE" gates because they would be safer for the environment and bring back the frequency of flooding to the very acceptable level of about one century ago, thus making possible to gain a few decades. This would give time to verify ongoing evolution and probably to narrow the large uncertainty ranges of present-day estimations. Only with a closer assessment of near-future sea-level rise will it be possible to decide which type of "hard" defence would be eventually necessary to save Venice and its lagoon. Anyway, a stricter control of water pollution should be a priority intervention.

  8. Peat Land Oxidation Enhances Subsidence in the Venice Watershed

    NASA Astrophysics Data System (ADS)

    Gambolati, Giuseppe; Putti, Mario; Teatini, Pietro; Camporese, Matteo; Ferraris, Stefano; Stori, Giuseppe Gasparetto; Nicoletti, Vincenzo; Silvestri, Sonia; Rizzetto, Federica; Tosi, Luigi

    2005-06-01

    The southernmost part of the Venice Lagoon catchment was progressively reclaimed from marshland starting from the end of the 19th century and finishing in the late 1930s (Figure 1). As a major result, the area was turned into a fertile farmland. At present, the area is kept dry by a distributed drainage system that collects the water from a capillary network of ditches, and pumps it into the lagoon or the sea. By its very origin this area lies below sea level and progressively sinks mainly because of bio-oxidation of the histosols (soils with high organic content) that represent a large fraction of the outcropping soil in the area. The bio-oxidation process occurs in close connection with the agricultural practices and is currently responsible for a subsidence rate of between 1.5 and 2 cm/yr. The Venice Organic Soil Subsidence (VOSS) project was undertaken with the objective of understanding the process of land settlement in this area, quantifying past and present subsidence rates, and advancing possible remedial measures that would not penalize the current agricultural activities of the area. The study, conducted in close collaboration with the local Land Reclamation Authority (Consorzio di Bonifica) and the farmland owners, is focused on a hydrologically controlled catchment, the Zennare Basin (Venice, Italy).

  9. Early afterdepolarizations and cardiac arrhythmias.

    PubMed

    Weiss, James N; Garfinkel, Alan; Karagueuzian, Hrayr S; Chen, Peng-Sheng; Qu, Zhilin

    2010-12-01

    Early afterdepolarizations (EADs) are an important cause of lethal ventricular arrhythmias in long QT syndromes and heart failure, but the mechanisms by which EADs at the cellular scale cause arrhythmias such as polymorphic ventricular tachycardia (PVT) and torsades de pointes (TdP) at the tissue scale are not well understood. Here we summarize recent progress in this area, discussing (1) the ionic basis of EADs, (2) evidence that deterministic chaos underlies the irregular behavior of EADs, (3) mechanisms by which chaotic EADs synchronize in large numbers of coupled cells in tissue to overcome source-sink mismatches, (4) how this synchronization process allows EADs to initiate triggers and generate mixed focal reentrant ventricular arrhythmias underlying PVT and TdP, and (5) therapeutic implications.

  10. Ranolazine Therapy in Cardiac Arrhythmias.

    PubMed

    Pulford, Brian R; Kluger, Jeffrey

    2016-09-01

    Ranolazine is an antianginal medication originally granted approval by the U.S. Food and Drug Administration for therapeutic use in 2006. Since its introduction into the U.S. market, there have been multiple trials and clinical case reports that demonstrate ranolazine may be effective in the prevention and treatment of both atrial and ventricular arrhythmias, including postoperative atrial fibrillation following coronary artery bypass graft (CABG) surgery. More recently, the combination of dronedarone with ranolazine has demonstrated in initial studies to have a synergistic effect in the reduction of burden of atrial fibrillation. This article will review the basic pharmacology of ranolazine, the studies demonstrating use of ranolazine in atrial and ventricular arrhythmias, the limitations to the use of ranolazine as antiarrhythmic therapy, and explore the synergistic effect with other agents in the suppression of arrhythmias.

  11. 76 FR 4651 - Venice Gathering System, L.L.C.; Notice of Request Under Blanket Authorization

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Venice Gathering System, L.L.C.; Notice of Request Under Blanket Authorization January 19, 2010. Take notice that on January 7, 2011, Venice Gathering System, L.L.C....

  12. Sudden Arrhythmia Death Syndromes (SADS) Foundation

    MedlinePlus

    ... Family Seminar 04/29/17 Update on Inherited Arrhythmias: Recent Advancements in Therapies and Diagnosis--From 8: ... Legal Notice Privacy Policy COPYRIGHT ©2011-2016 Sudden Arrhythmia Death Syndromes Foundation 4527 South 2300 East, Suite ...

  13. Cardioverter-Defibrillator: A Treatment for Arrhythmia

    MedlinePlus

    ... life-threatening arrhythmias, including ventricular tachycardia and ventricular fibrillation.Ventricular tachycardia (say: "tack-ee-card-ee-ya") ... type of arrhythmia can be life threatening.Ventricular fibrillation is when the bottom chambers of your heart ( ...

  14. Cardiac arrhythmias in paediatric practice.

    PubMed

    Chan, K Y; Loke, K Y; Yip, W C; Tay, J S

    1989-01-01

    Clinical data of patients with cardiac arrhythmias managed between May 1986 and March 1988 were reviewed to determine their mode of presentation and clinical course. Of the 5,768 admissions, 62 (1.07%) patients had arrhythmias. During the same period, 21 patients were managed as outpatients with 13 being new referrals. Thirty-eight patients had undergone corrective cardiac procedures, 8 others had congenital heart lesions, 3 were associated with acquired cardiac pathology and the remaining had isolated arrhythmias. The cardiac arrhythmias were: right bundle branch block 36, premature atrial and ventricular contractions 15, supraventricular tachycardia (SVT) 15, atrioventricular (AV) block 7, sinus bradycardia 3, atrial fibrillation 2, ventricular tachycardia and fibrillation 2, Wolff-Parkinson-White syndrome without SVT 2, bradytachyarrhythmia 1. There were 3 patients with foetal SVT, one persisting till day 1. High grade AV block occurred in 2 patients post-surgically and needed pacing. Only 2 others were symptomatic. Other than the 38 patients who underwent corrective procedures (2 had balloon valvuloplasty for pulmonary stenosis), 8 others had structural heart disease. There was 1 sudden death and 5 died from their primary heart disease.

  15. Eukaryotic ribosomes that lack a 5.8S RNA

    NASA Technical Reports Server (NTRS)

    Vossbrinck, C. R.; Woese, C. R.

    1986-01-01

    The 5.8S ribosomal RNA is believed to be a universal eukaryotic characteristic. It has no (size) counterpart among the prokaryotes, although its sequence is homologous with the first 150 or so nucleotides of the prokaryotic large subunit (23S) ribosomal RNA. An exception to this rule is reported here. The microsporidian Vairimorpha necatrix is a eukaryote that has no 5.8S rRNA. As in the prokaryotes, it has a single large subunit rRNA, whose 5-prime region corresponds to the 5.8S rRNA.

  16. Dynamic processes in the Venice region outlined by environmental isotopes.

    PubMed

    Zuppi, Gian Maria; Sacchi, Elisa

    2004-03-01

    Research carried out in the last 40 years has shown the scientific importance of groundwater circulation both in the Northern Adriatic sea bed and within the uppermost sedimentary layers of the Venice lagoon and of the Venice plain. Hydrodynamic processes are strictly controlled by a well-cemented sedimentary horizon lying under and around Venice ('caranto'), which plays the role of regional aquitard. This layer was attributed to the subaerial cementation of the Flandrian (8-10 ka Before Present) sedimentary surface. The caranto is generalised as a continuum horizon, being an easy explanation for several environmental, hydrogeological and geotechnical problems, e.g., a base layer for landfills, a confining layer for deep aquifers and the best substratum for locating the oak wooden pile-dwelling needed to support the largest buildings. The preservation of the isotope signal within the deep aquifers and aquiclude system records the changes in surface and groundwater characteristics and suggests the present and past recharge regimes. In this region, the heavily perturbed hydrodynamic conditions do not allow for the use of isotopic signals to derive a correct reconstruction of the present recharge. The perturbations induced by the intensive anthropogenic activity force to follow climate evolution by considering deep groundwater and pore waters. In addition, the presence of carbonatic rocks inside terrigeneous sediments affects the reconstruction of the past. Results indicate that carbonatic rocks are created by seepage, through the sediments, of gaseous carbon compounds from decaying organic layers. The gas interactions with the intra-sedimentary saline and fresh waters produce CO2, inducing the cementation of the sediments.

  17. A new hydrogeologic model to predict anthropogenic uplift of Venice

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Castelletto, N.; Ferronato, M.; Gambolati, G.; Tosi, L.

    2011-12-01

    Recent numerical studies based on a simplified lithostratigraphy of the Venice subsurface suggest that the city may be raised by pumping seawater into deep aquifers through 12 wells located on a 10 km diameter circle. Using an updated 3-D reconstruction of the Quaternary deposits, developed very recently from about 1050 km of multichannel seismic profiles and eight exploration wells, along with a more accurate representation of the injection boreholes, novel finite-element predictions are performed. The new model simulates the lithostratigraphy of the lagoon subsurface and allows for a reliable assessment of the water volumes injected into the geologic formations based on the actual bottom hole overpressure that can vary both in space and time. Pumping occurs into two Pleistocene sequences that are originated from the Alps and Apennine sedimentation and terminate just south and north of Venice, respectively, and the shelf portion of a Pliocene sequence that is rather continuous below the central lagoon with arenite layers to depths as much as 1000 m below mean sea level. With a proper tuning of the injection pressure the new hydrogeologic model allows for a prediction of a quite uniform 25-30 cm uplift over 10 years after the inception of injection. The gradient of the vertical displacement ξz does not exceed 5 × 10-5 and 1 × 10-5 in the whole lagoon and Venice, respectively, i.e., well below the most conservative bound recommended for the safety of the structures. If ad hoc calibrated injection overpressures are implemented in each single well, ξz may be reduced to as much as 0.1 × 10-5 throughout the city.

  18. Floating call boys and agile homosexuals: homophobia/Venice/history.

    PubMed

    Champagne, John

    2014-01-01

    Because works of nonfiction are always composed of literary tropes and metaphors, they have to be read critically for the ways in which their truth claims are potentially structured by ideologies and stereotypes. This essay reads passages from Richard Sennett's sociological analysis Flesh and Stone, The Body and the City in Western Civilization and Joseph Brodsky's memoir Watermark in order to demonstrate how these alleged works of nonfiction shore up some dishearteningly familiar literary stereotypes of male homosexuality and participate in a tradition, dating from the 19th century, of linking the city of Venice with homosexuality and death.

  19. Common cardiac arrhythmias: recognition and treatment.

    PubMed

    Talmers, F N; Kinhal, V; Sabharwal, S; Weissler, A M

    1981-04-01

    Cardiac arrhythmias are commonly seen in the everyday practice of medicine by the physician. Although certain arrhythmias may be suspected clinically, precise diagnosis is made by electrocardiographic recording of the abnormal rhythm. Once the arrhythmia has been recorded, the next steps are proper electrocardiographic diagnosis and selection of proper treatment. The specific mode of therapy and the speed with which it is delivered will depend not only on the type of arrhythmia, but also on the hemodynamic consequences of the rhythm abnormality on the patient's cardiovascular system. The purpose of this paper is to discuss the electrocardiographic criteria of common cardiac arrhythmias as well as current concepts regarding therapy.

  20. Cardiac Arrhythmias: Diagnosis, Symptoms, and Treatments.

    PubMed

    Fu, Du-Guan

    2015-11-01

    The cardiac arrhythmia is characterized by irregular rhythm of heartbeat which could be either too slow (<60 beats/min) or too fast (>100 beats/min) and can happen at any age. The use of pacemaker and defibrillators devices has been suggested for heart arrhythmias patients. The antiarrhythmic medications have been reported for the treatment of cardiac arrhythmias or irregular heartbeats. The diagnosis, symptoms, and treatments of cardiac arrhythmias as well as the radiofrequency ablation, tachycardia, Brugada syndrome, arterial fibrillation, and recent research on the genetics of cardiac arrhythmias have been described here.

  1. Evaluation and Management of Maternal Cardiac Arrhythmias.

    PubMed

    Metz, Torri D; Khanna, Amber

    2016-12-01

    Pregnant women often complain of palpitations. The differential diagnosis for new-onset palpitations in pregnancy ranges from benign conditions to life-threatening arrhythmias. Maternal arrhythmias can occur in isolation or in the setting of underlying structural heart disease. Optimal management of maternal cardiac arrhythmias includes identification of the specific arrhythmia, diagnosis of comorbid conditions, and appropriate intervention. In general, management of maternal cardiac arrhythmias is similar to that of the general population. Special consideration must be given as to the effects of medications and procedures on both the mother and fetus to optimize outcomes. The importance of multidisciplinary care with cardiology, obstetrics, and anesthesia is emphasized.

  2. [Maternal arrhythmias during pregnancy. Practical review].

    PubMed

    Kornacewicz-Jach, Zdzisława; Peregud-Pogorzelska, Małgorzata

    2014-01-01

    Pregnancy is accompanied by a variety of cardiovascular changes in normal women, and these changes can increased incidence of maternal cardiac arrhythmias. Supraventricular and ventricular arrhythmias reguiring treatment are rarely seen during pregnancy in healthy women. Structural cardiac defects or residual defects after repair may contribute to the occurrence of clinically relevant arrhythmias. Arrhythmias during pregnancy include a wide spectrum. The most common are simple ventricular and atrial ectopy, sinusal tachycardia and supraventricular tachycardia. The foetus may suffer both haemodynamic alternations and adverse effects of the treatment (teratogenic risk, foetal growth and development). The management of arrhythmias in pregnant women is similar to that taken in patients who are not pregnant.

  3. Catheter Ablation for Ventricular Arrhythmias

    PubMed Central

    Nof, Eyal; Stevenson, William G; John, Roy M

    2013-01-01

    Catheter ablation has emerged as an important and effective treatment option for many recurrent ventricular arrhythmias. The approach to ablation and the risks and outcomes are largely determined by the nature of the severity and type of underlying heart disease. In patients with structural heart disease, catheter ablation can effectively reduce ventricular tachycardia (VT) episodes and implantable cardioverter defibrillator (ICD) shocks. For VT and symptomatic premature ventricular beats that occur in the absence of structural heart disease, catheter ablation is often effective as the sole therapy. Advances in catheter technology, imaging and mapping techniques have improved success rates for ablation. This review discusses current approaches to mapping and ablation for ventricular arrhythmias. PMID:26835040

  4. Remote Arrhythmia Monitoring System Developed

    NASA Technical Reports Server (NTRS)

    York, David W.; Mackin, Michael A.; Liszka, Kathy J.; Lichter, Michael J.

    2004-01-01

    Telemedicine is taking a step forward with the efforts of team members from the NASA Glenn Research Center, the MetroHealth campus of Case Western University, and the University of Akron. The Arrhythmia Monitoring System is a completed, working test bed developed at Glenn that collects real-time electrocardiogram (ECG) signals from a mobile or homebound patient, combines these signals with global positioning system (GPS) location data, and transmits them to a remote station for display and monitoring. Approximately 300,000 Americans die every year from sudden heart attacks, which are arrhythmia cases. However, not all patients identified at risk for arrhythmias can be monitored continuously because of technological and economical limitations. Such patients, who are at moderate risk of arrhythmias, would benefit from technology that would permit long-term continuous monitoring of electrical cardiac rhythms outside the hospital environment. Embedded Web Technology developed at Glenn to remotely command and collect data from embedded systems using Web technology is the catalyst for this new telemetry system (ref. 1). In the end-to-end system architecture, ECG signals are collected from a patient using an event recorder and are transmitted to a handheld personal digital assistant (PDA) using Bluetooth, a short-range wireless technology. The PDA concurrently tracks the patient's location via a connection to a GPS receiver. A long distance link is established via a standard Internet connection over a 2.5-generation Global System for Mobile Communications/General Packet Radio Service (GSM/GPRS)1 cellular, wireless infrastructure. Then, the digital signal is transmitted to a call center for monitoring by medical professionals.

  5. [Delusion and dreams in "Death in Venice". Thomas Mann's consequential reading of Freud in 1911].

    PubMed

    Dierks, M

    1990-03-01

    The author shows by means of literary comparisons that in "Death in Venice" and The Magic Mountain, Mann was strongly influenced by Freud's psychoanalysis, in particular by the latter's work "Delusion and dreams in W. Jensen's 'Gradiva'."

  6. Global Issues in the Intermediate Classroom, Grades 5-8.

    ERIC Educational Resources Information Center

    Johnson, Jacquelyn; Benegar, John

    This publication contains teacher developed activities for teaching about global issues in grades 5-8. The self-contained activities are organized into three major parts. Part I, "Global Awareness," introduces students to the concept of global education. Students are made aware of the nature of the world and the part they play in it as inhabitants…

  7. 17 CFR 5.8 - Aggregate retail forex assets.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Aggregate retail forex assets... FOREIGN CURRENCY TRANSACTIONS § 5.8 Aggregate retail forex assets. (a) Each retail foreign exchange dealer and futures commission merchant offering or engaging in retail forex transactions shall calculate...

  8. 17 CFR 5.8 - Aggregate retail forex assets.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Aggregate retail forex assets... FOREIGN CURRENCY TRANSACTIONS § 5.8 Aggregate retail forex assets. (a) Each retail foreign exchange dealer and futures commission merchant offering or engaging in retail forex transactions shall calculate...

  9. 17 CFR 5.8 - Aggregate retail forex assets.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Aggregate retail forex assets... FOREIGN CURRENCY TRANSACTIONS § 5.8 Aggregate retail forex assets. (a) Each retail foreign exchange dealer and futures commission merchant offering or engaging in retail forex transactions shall calculate...

  10. 17 CFR 5.8 - Aggregate retail forex assets.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... merchant may not include aggregate retail forex assets as current assets or otherwise record any property... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Aggregate retail forex assets... FOREIGN CURRENCY TRANSACTIONS § 5.8 Aggregate retail forex assets. (a) Each retail foreign exchange...

  11. Ideas: NCTM Standards-Based Instruction, Grades 5-8.

    ERIC Educational Resources Information Center

    Hynes, Michael C., Ed.

    This document is a collection of activity-based mathematics lessons for grades 5-8 from the "Ideas" department in "Arithmetic Teacher: Mathematics Education through the Middle Grades." Each lesson includes background information, objectives, directions, extensions, and student worksheets. A matrix is included which correlates…

  12. Update on arrhythmias and cardiac pacing 2013.

    PubMed

    Almendral, Jesús; Pombo, Marta; Martínez-Alday, Jesús; González-Rebollo, José M; Rodríguez-Font, Enrique; Martínez-Ferrer, José; Castellanos, Eduardo; García-Fernández, F Javier; Ruiz-Mateas, Francisco

    2014-04-01

    This report discusses a selection of the most relevant articles on cardiac arrhythmias and pacing published in 2013. The first section discusses arrhythmias, classified as regular paroxysmal supraventricular tachyarrhythmias, atrial fibrillation, and ventricular arrhythmias, together with their treatment by means of an implantable cardioverter defibrillator. The next section reviews cardiac pacing, subdivided into resynchronization therapy, remote monitoring of implantable devices, and pacemakers. The final section discusses syncope.

  13. Macroalgae, nutrient cycles, and pollutants in the lagoon of Venice

    SciTech Connect

    Sfriso, A.; Pavoni, B.; Marcomini, A.; Orio, A.A. )

    1992-12-01

    The Lagoon of Venice is a wide, shallow coastal basin that extends for about 50 km along the northwest coast of the Adriatic Sea. The lagoon has been substantially modified through the actions of man over the last century through the artificial control of the hydraulic dynamics of the lagoon including the construction of channels to facilitate navigation. The lagoon is subjected to considerable pollutant loading through the drainage of land under cultivation, municipal sewage, and industrial effluents. In this paper are reported the results of observations designed to document recent changes in macroalgal species composition, seasonal cycles of primary producers and nutrient levels, and the effects of the macroalgal community on concentrations of organic and inorganic pollutants. The dominant macroalgae in the lagoon was Ulva rigida, and the levels of plant nutrients and pollutants were influenced by the seasonal cycles of the macroalgal community. 44 refs., 11 figs., 2 tabs.

  14. Carbon monoxide and lethal arrhythmias

    SciTech Connect

    Farber, J.P.; Schwartz, P.J.; Vanoli, E.; Stramba-Badiale, M.; De Ferrari, G.M. )

    1990-12-01

    The effect of acute exposure to carbon monoxide on ventricular arrhythmias was studied in a previously described chronically maintained animal model of sudden cardiac death. In 60 percent of dogs with a healed anterior myocardial infarction, the combination of mild exercise and acute myocardial ischemia induces ventricular fibrillation. The events in this model are highly reproducible, thus allowing study by internal control analysis. Dogs that develop ventricular fibrillation during the test of exercise and acute myocardial ischemia are considered at high risk for sudden death and are defined as 'susceptible'; dogs that survive the test without a fatal arrhythmia are considered at low risk for sudden death and are defined as 'resistant.' In the current study, the effects of carboxyhemoglobin levels ranging from 5 to 15 percent were tested in resistant and susceptible dogs. A trend toward higher heart rates was observed at all levels of carboxyhemoglobin, although significant differences were observed only with 15 percent carboxyhemoglobin. This trend was observed at rest and during exercise in both resistant and susceptible dogs. In resistant animals, in which acute myocardial ischemia is typically associated with bradycardia even under the control condition, this reflex response occurred earlier and was augmented after exposure to carbon monoxide. This effect may depend on the increased hypoxic challenge caused by carbon monoxide, and thus on an augmentation of the neural reflex activation or a sensitization of the sinus node to acetylcholine induced by hypoxia. In both resistant and susceptible dogs, carbon monoxide exposure induced a worsening of ventricular arrhythmias in a minority of cases. This worsening was not reproducible in subsequent trials. These data indicate that acute exposure to carbon monoxide is seldom arrhythmogenic in dogs that have survived myocardial infarction. (Abstract Truncated)

  15. Statistical characterization of spatiotemporal sediment dynamics in the Venice lagoon

    NASA Astrophysics Data System (ADS)

    Carniello, Luca; D'Alpaos, Andrea; Botter, Gianluca; Rinaldo, Andrea

    2016-05-01

    Characterizing the dynamics of suspended sediment is crucial when investigating the long-term evolution of tidal landscapes. Here we apply a widely tested mathematical model which describes the dynamics of cohesive and noncohesive sediments, driven by the combined effect of tidal currents and wind waves, using 1 year long time series of observed water levels and wind data from the Venice lagoon. The spatiotemporal evolution of the computed suspended sediment concentration (SSC) is analyzed on the basis of the "peak over threshold" theory. Our analysis suggests that events characterized by high SSC can be modeled as a marked Poisson process over most of the lagoon. The interarrival time between two consecutive over threshold events, the intensity of peak excesses, and the duration are found to be exponentially distributed random variables over most of tidal flats. Our study suggests that intensity and duration of over threshold events are temporally correlated, while almost no correlation exists between interarrival times and both durations and intensities. The benthic vegetation colonizing the central southern part of the Venice lagoon is found to exert a crucial role on sediment dynamics: vegetation locally decreases the frequency of significant resuspension events by affecting spatiotemporal patterns of SSCs also in adjacent areas. Spatial patterns of the mean interarrival of over threshold SSC events are found to be less heterogeneous than the corresponding patterns of mean interarrivals of over threshold bottom shear stress events because of the role of advection/dispersion processes in mixing suspended sediments within the lagoon. Implications for long-term morphodynamic modeling of tidal environments are discussed.

  16. Terlipressin-induced ventricular arrhythmia.

    PubMed

    Urge, Ján; Sincl, Frantisek; Procházka, Vlastimil; Urbánek, Karel

    2008-01-01

    During intravenous treatment with terlipressin for recurrent gastrointestinal (GI) bleeding, a 50-year-old male with no history of heart disease developed a newly prolonged QT interval and torsade de pointes. Risk factors present for acquired long QT syndrome were mineral dysbalance and a history of alcohol abuse with hepatic impairment. The patient was brought back to a normal sinus rhythm after a single 300-J counter-shock. Terlipressin was discontinued, and the patient's QTc interval subsequently returned to baseline. During 6 weeks of monitoring, arrhythmia did not recur.

  17. Arrhythmias

    MedlinePlus

    ... the doctor. Pacemakers. A pacemaker is a small battery-operated device implanted into the body (near the ... to speed up the heartbeat. Defibrillators. A small battery-operated implantable cardioverter defibrillator (ICD) is surgically placed ...

  18. Arrhythmias

    MedlinePlus

    Abnormal heart rhythms; Bradycardia; Tachycardia; Fibrillation ... the more common abnormal heart rhythms are: Atrial fibrillation or flutter Atrioventricular nodal reentry tachycardia (AVNRT) Heart ...

  19. Perinatal Arrhythmias: Diagnosis and Management

    PubMed Central

    Strasburger, Janette F.; Cheulkar, Bageshree; Wichman, Heather J.

    2012-01-01

    The final common pathway to death in all of us is an arrhythmia, yet we still know far too little about the contribution of conduction abnormalities and arrhythmias to the compromised states of the human fetus. At no other time in the human life cycle is the human being at more risk of unexplained and unexpected death than during the prenatal period. The risk of sudden death from 20 to 40 weeks gestation is 6 to 12 deaths/1000 fetuses/year. This is equal to, and in some ethnic groups HIGHER, than the risk of death in the adult population with known coronary artery disease over the same time frame (6 to 12 deaths/1000 patients/year). Because only a small percentage of the United States population is pregnant each year, because fetal demise is not often acknowledged through public displays such as funerals, and finally because fetal death is culturally accepted to a much greater extent than it should be, this critically important area of women’s healthcare has not had the technological advances that have been seen in adult cardiac intensive care and other areas of medicine. Fetal cardiac deaths may be preventable and the diseases that lead to these deaths are often treatable, especially if the sophistication of our modern ICU’s could somehow be translated to the prenatal monitoring arena. PMID:18063110

  20. Improvements of Storm Surge Modelling in the Gulf of Venice with Satellite Data: The ESA Due Esurge-Venice Project

    NASA Astrophysics Data System (ADS)

    De Biasio, F.; Bajo, M.; Vignudelli, S.; Papa, A.; della Valle, A.; Umgiesser, G.; Donlon, C.; Zecchetto, S.

    2016-08-01

    Among the most detrimental natural phenomena, storm surges heavily endanger the environment, the economy and the everyday life of sea-side countries and coastal zones. Considering that 120.000.000 people live in the Mediterranean area, with additional 200.000.000 presences in Summer for tourism purposes, the correct prediction of storm surges is crucial to avoid fatalities and economic losses. Earth Observation (EO) can play an important role in operational storm surge forecasting, yet it is not widely diffused in the storm surge community. In 2011 the European Space Agency (ESA), through its Data User Element (DUE) programme, financed two projects aimed at encouraging the uptake of EO data in this sector: eSurge and eSurge-Venice (eSV). The former was intended to address the issues of a wider users' community, while the latter was focused on a restricted geographical area: the northern Adriatic Sea and the Gulf of Venice. Among the objectives of the two projects there were a number of storm surge hindcast experiments using satellite data, to demonstrate the improvements on the surge forecast brought by EO. We report here the results of the hindcast experiments of the eSV project. They were aimed to test the sensitivity of a storm surge model to a forcing wind field modified with scatterometer data in order to reduce the bias between simulated and observed winds. Hindcast experiments were also performed to test the response of the storm surge model to the assimilation, with a dual 4D-Var system, of satellite altimetry observations as model errors of the initial state of the sea surface level. Remarkable improvements on the storm surge forecast have been obtained for what concerns the modified model wind forcing. Encouraging results have been obtained also in the assimilation experiments.

  1. Atrial Arrhythmia Summit: Post Summit Report

    NASA Technical Reports Server (NTRS)

    Barr, Yael

    2010-01-01

    The Atrial Arrhythmia Summit brought together nationally and internationally recognized experts in cardiology, electrophysiology, exercise physiology, and space medicine in an effort to elucidate the mechanisms, risk factors, and management of atrial arrhythmias in the unique occupational cohort of the U.S. astronaut corps.

  2. Update in cardiac arrhythmias and pacing.

    PubMed

    García-Bolao, Ignacio; Ruiz-Mateas, Francisco; Bazan, Victor; Berruezo, Antonio; Alcalde, Oscar; Leal del Ojo, Juan; Acosta, Juan; Martínez Sellés, Manuel; Mosquera, Ignacio

    2015-03-01

    This article discusses the main advances in cardiac arrhythmias and pacing published between 2013 and 2014. Special attention is given to the interventional treatment of atrial fibrillation and ventricular arrhythmias, and on advances in cardiac pacing and implantable cardioverter defibrillators, with particular reference to the elderly patient.

  3. Evaluation of Cardiac Arrhythmia among Athletes

    PubMed Central

    Walker, James; Calkins, Hugh; Nazarian, Saman

    2010-01-01

    Due to the growing awareness of exercise related arrhythmias and improved sensitivity of diagnostic modalities, physicians are increasingly faced with choices that may have life changing impact for the athlete. This article surveys recent research and expert opinion addressing benign and pathogenic cardiac changes underlying arrhythmias in athletes. PMID:20870195

  4. Ship traffic and shoreline erosion in the Lagoon of Venice

    NASA Astrophysics Data System (ADS)

    Scarpa, Gian Marco; Zaggia, Luca; Lorenzetti, Giuliano; Manfè, Giorgia; Parnell, Kevin; Molinaroli, Emanuela; Rapaglia, John; Gionta, Sofia

    2016-04-01

    A study based on the analysis of a historical sequence of aerial photographs and satellite images combined with in situ measurements revealed an unprecedented shoreline regression on the side of a major waterway in the Venice Lagoon, Italy. The study considered long and short-term recession rates caused by ship-induced depression wakes in an area which was reclaimed at the end of the '60 for the expansion of the nearby Porto Marghera Industrial Zone and never used since then. The GIS analysis performed with the available imagery shows an average retreat of about 4 m yr-1 in the period between 1965 and 2015. Field measurements carried out between April 2014 and January 2015 also revealed that the shoreline's regression still proceed with a speed comparable to the long-term average regardless of the distance from the navigation channel and is not constant through time. Periods of high water levels determined by astronomical tide or storm surges, more common in the winter season, are characterized by faster regression rates. The retreat proceeds by collapse of slabs of the reclaimed muddy soil after erosion and removal of the underlying original salt marsh sediments and is a discontinuous process in time and space depending on morphology, intrinsic propertiesand vegetation cover of the artificial deposits. Digitalization of historical maps and new bathymetric surveys made in April 2015 allowed for the reconstruction of two digital terrain models for both past and present situations. The two models have been used to calculate the total volume of sediment lost during the period between 1970 and 2015. The results of this study shows as ship-channel interactions can dominate the morphodynamics of a waterway and its margins and permitted to better understand how this part of the Venice Lagoon reacted to the pressure of human activities in the post-industrial period. Evaluation of the temporal and spatial variation of shoreline position is also crucial to predict future

  5. Cardiac arrhythmias during or after epileptic seizures.

    PubMed

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D

    2016-01-01

    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: 'cardiac arrhythmias' and 'epilepsy'. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP.

  6. Constitutive signifiers or fetishes in Shakespeare's the Merchant of Venice?

    PubMed

    Sokol, B J

    1995-04-01

    Assessments of psychodynamic structures and processes implicit in 'The Merchant of Venice' vary considerably according to whether Lacanian or object-relations tenets are applied. Aspects of the play resemble a pattern described in Lacan's seminar on E. A. Poe's story 'The purloined letter': the 'itinerary' of the 'signifier' represented by a roving letter in Poe's story closely matches in outline the adventures surrounding roving rings in Shakespeare's play. Using Poe's story as evidence, Lacan's seminar argues that human identity is a product of 'signifiers', and not vice-versa. This conclusion that human subjectivities are constituted by signifiers does not stand up well in relation to the power of the rings and other signifying physical objects appearing in Shakespeare's play and its source stories. Recently expanded understandings of Freud's ideas about fetishism better explain the often malevolent power of the play's many signifying physical objects. In these the essential potential for damage is to sound personal relations with inner and outer objects of love. Explanations emphasising that distorted object relations and damaged subjectivities may be redeemed accord well with the dramatic and poetic patterns of Shakespeare's play, indicating that it, while portraying painful dilemmas, is still a comedy.

  7. Venice and I: How a City Can Determine the Fate of a Career

    NASA Astrophysics Data System (ADS)

    Malanotte-Rizzoli, Paola

    2017-01-01

    Quoting the ancient Romans: Audentes Fortuna iuvat. Being in the right place at the right time is useless if you do not grasp your Fortuna and build upon it. In this article, I expound on the milestones of my multiform research career, which over more than 40 years brought me from Venice to California to MIT; from the Venice problem to highly nonlinear, coherent structures in the ocean and atmosphere; and from the mare nostrum (the Mediterranean Sea), a laboratory for global processes, to the tropical ocean-atmosphere systems and regional coupled climate models of the Maritime Continent. The climate system, with its daunting complexity, is arguably the greatest challenge for, and the future of, the entirety of the earth sciences. Finally, living in and working for Venice has been the privilege and Fortuna of my life.

  8. Venice and I: How a City Can Determine the Fate of a Career.

    PubMed

    Malanotte-Rizzoli, Paola

    2017-01-03

    Quoting the ancient Romans: Audentes Fortuna iuvat. Being in the right place at the right time is useless if you do not grasp your Fortuna and build upon it. In this article, I expound on the milestones of my multiform research career, which over more than 40 years brought me from Venice to California to MIT; from the Venice problem to highly nonlinear, coherent structures in the ocean and atmosphere; and from the mare nostrum (the Mediterranean Sea), a laboratory for global processes, to the tropical ocean-atmosphere systems and regional coupled climate models of the Maritime Continent. The climate system, with its daunting complexity, is arguably the greatest challenge for, and the future of, the entirety of the earth sciences. Finally, living in and working for Venice has been the privilege and Fortuna of my life.

  9. Demons, nature, or God? Witchcraft accusations and the French disease in early modern Venice.

    PubMed

    McGough, Laura J

    2006-01-01

    In early modern Venice, establishing the cause of a disease was critical to determining the appropriate cure: natural remedies for natural illnesses, spiritual solutions for supernatural or demonic ones. One common ailment was the French disease (syphilis), widely distributed throughout Venice's neighborhoods and social hierarchy, and evenly distributed between men and women. The disease was widely regarded as curable by the mid-sixteenth century, and cases that did not respond to natural remedies presented problems of interpretation to physicians and laypeople. Witchcraft was one possible explanation; using expert testimony from physicians, however, the Holy Office ruled out witchcraft as a cause of incurable cases and reinforced perceptions that the disease was of natural origin. Incurable cases were explained as the result of immoral behavior, thereby reinforcing the associated stigma. This article uses archival material from Venice's Inquisition records from 1580 to 1650, as well as mortality data.

  10. Arrhythmias in the Heart Transplant Patient

    PubMed Central

    Hamon, David; Taleski, Jane; Vaseghi, Marmar; Shivkumar, Kalyanam

    2014-01-01

    Orthotopic heart transplantation (OHT) is currently the most effective long-term therapy for patients with end-stage cardiac disease, even as left ventricular devices show markedly improved outcomes. As surgical techniques and immunosuppressive regimens have been refined, short-term mortality caused by sepsis has decreased, while morbidity caused by repeated rejection episodes and vasculopathy has increased, and is often manifested by arrhythmias. These chronic transplant complications require early and aggressive multidisciplinary treatment. Understanding the relationship between arrhythmias and these complications in the acute and chronic stages following OHT is critical in improving patient prognosis, as arrhythmias may be the earliest or sole presentation. Finally, decentralised/ denervated hearts represent a unique opportunity to investigate the underlying mechanisms of arrhythmias. PMID:26835083

  11. Effect of female sex on cardiac arrhythmias.

    PubMed

    Gowd, B M Pampana; Thompson, Paul D

    2012-01-01

    We performed a systematic literature review to examine the effect of female sex on cardiac electrophysiology and arrhythmias. Women have faster resting heart rates yet longer QTc intervals. Women also have shorter PR and QRS intervals; these are presumed to be due to the small heart size of women and hormonal effects on ion channels. Women are two times more likely to experience atrioventricular nodal re-entry tachycardia than men. In contrast to atrioventricular nodal re-entry tachycardia, accessory-pathway-mediated atrial arrhythmias are less common in women, and women have more concealed and fewer manifest accessory pathways. Supraventricular tachycardia in women varies with the menstrual cycle and is more frequent in the luteal phase and inversely correlated with estrogen levels. Atrial fibrillation (AF) is less prevalent in women, but the absolute number of women with AF is higher because AF prevalence increases with age and women live longer. Also, complications of AF are greater in women. Women are generally less prone to ventricular arrhythmias, but they comprise a higher percentage of symptomatic subjects with congenital long QT syndrome and are more often affected by drugs that prolong the QT. Women are less prone to arrhythmias during pregnancy although they commonly complain of palpitations, which are sometimes related to the increase in heart rate during pregnancy. Clinicians should explore the relationship of arrhythmias to the menstrual cycle in female patients and should know that the menstrual cycle may affect the induction of arrhythmias during electrophysiological testing. Clinicians should also be aware that the arrhythmia and the result of clinical trials examining arrhythmia treatment may have different implications in women than in men.

  12. Diagnosis and management of common fetal arrhythmias

    PubMed Central

    Weber, Roland; Stambach, Dominik; Jaeggi, Edgar

    2011-01-01

    Fetal arrhythmias are detected in at least 2% of unselected pregnancies during routine obstetrical scans. Most common are transient, brief episodes of a slow or fast heart rate or of an irregular heart rhythm. Less common are prolonged or persistent abnormalities such as supraventricular tachycardia and complete heart block which may lead to low cardiac output, fetal hydrops and demise. The objectives of this review are to update the reader on the diagnosis and management of the more common arrhythmias. PMID:23960639

  13. The effects of dilazep on reperfusion arrhythmias.

    PubMed

    Sugiyama, S; Kondo, T; Ajioka, M; Hattori, M; Nagai, S; Ozawa, T

    1985-01-01

    The effects of 3,3'-(perhydro-1,4-diazepine-1,4-diyl) (propyl-3,4,5-trimethoxybenzoate (dilazep, Comelian) on reperfusion arrhythmias were investigated. 49 adult mongrel dogs were divided into 2 groups; the control group (n = 38) and the dilazep group (n = 11). 15 min after premedication with physiological saline or dilazep (2 mg/kg), the left anterior descending coronary artery was occluded for 15 min and then reperfused for 5 min. 12 dogs (32%) of the control developed "reperfusion arrhythmias" (arrhythmias cases) but 26 did not (non-arrhythmias cases). None of the 11 dogs pretreated with dilazep developed arrhythmias (dilazep group). Immediately after 5 min of reperfusion, plasma membrane and microsomes were prepared from the normal and reperfused myocardium. In the arrhythmias cases of the control group, an increase in free fatty acids and a decrease in phospholipids of plasma membrane obtained from the reperfused myocardium were observed. The endogenous phospholipase activity in the heart microsomes obtained from reperfused myocardium increased significantly compared with that from the normal myocardium. In the non-arrhythmias cases of the control group and in the dilazep group, there was no significant difference in the contents of free fatty acids and phospholipids in plasma membrane between normal and reperfused area. Phospholipase activity in the microsomes prepared from the reperfused myocardium did not change significantly compared with that in the microsomes from normal area in these groups. These results suggest that the activation of phospholipases associated with coronary reperfusion is closely related to the development of reperfusion arrhythmias.

  14. Microwave Treatment for Cardiac Arrhythmias

    NASA Technical Reports Server (NTRS)

    Arndt, G. Dickey (Inventor); Carl, James R. (Inventor); Raffoul, George W. (Inventor); Pacifico, Antonio (Inventor)

    1999-01-01

    Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator having a surface wave limiter. A test setup provides physical testing of microwave radiators to determine the temperature profile created in actual heart tissue or ersatz heart tissue. Saline solution pumped over the heart tissue with a peristaltic pump simulates blood flow. Optical temperature sensors disposed at various tissue depths within the heart tissue detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter such as tumors and the like.

  15. Inherited arrhythmias: The cardiac channelopathies

    PubMed Central

    Behere, Shashank P; Weindling, Steven N

    2015-01-01

    Ion channels in the myocardial cellular membrane are responsible for allowing the cardiac action potential. Genetic abnormalities in these channels can predispose to life-threatening arrhythmias. We discuss the basic science of the cardiac action potential; outline the different clinical entities, including information regarding overlapping diagnoses, touching upon relevant genetics, new innovations in screening, diagnosis, risk stratification, and management. The special considerations of sudden unexplained death and sudden infant death syndrome are discussed. Scientists and clinicians continue to reconcile the rapidly growing body of knowledge regarding the molecular mechanisms and genetics while continuing to improve our understanding of the various clinical entities and their diagnosis and management in clinical setting. Two separate searches were run on the National Center for Biotechnology Information's website. The first using the term cardiac channelopathies was run on the PubMed database using filters for time (published in past 5 years) and age (birth-18 years), yielding 47 results. The second search using the medical subject headings (MeSH) database with the search terms “Long QT Syndrome” (MeSH) and “Short QT Syndrome” (MeSH) and “Brugada Syndrome” (MeSH) and “Catecholaminergic Polymorphic Ventricular Tachycardia” (MeSH), applying the same filters yielded 467 results. The abstracts of these articles were studied, and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles where further explored and read in full. PMID:26556967

  16. Cardiac arrhythmias during or after epileptic seizures

    PubMed Central

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D

    2016-01-01

    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: ‘cardiac arrhythmias’ and ‘epilepsy’. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP. PMID:26038597

  17. Gene therapy to treat cardiac arrhythmias.

    PubMed

    Bongianino, Rossana; Priori, Silvia G

    2015-09-01

    Gene therapy to treat electrical dysfunction of the heart is an appealing strategy because of the limited therapeutic options available to manage the most-severe cardiac arrhythmias, such as ventricular tachycardia, ventricular fibrillation, and asystole. However, cardiac genetic manipulation is challenging, given the complex mechanisms underlying arrhythmias. Nevertheless, the growing understanding of the molecular basis of these diseases, and the development of sophisticated vectors and delivery strategies, are providing researchers with adequate means to target specific genes and pathways involved in disorders of heart rhythm. Data from preclinical studies have demonstrated that gene therapy can be successfully used to modify the arrhythmogenic substrate and prevent life-threatening arrhythmias. Therefore, gene therapy might plausibly become a treatment option for patients with difficult-to-manage acquired arrhythmias and for those with inherited arrhythmias. In this Review, we summarize the preclinical studies into gene therapy for acquired and inherited arrhythmias of the atria or ventricles. We also provide an overview of the technical advances in the design of constructs and viral vectors to increase the efficiency and safety of gene therapy and to improve selective delivery to target organs.

  18. Migration Rate Of Tidal Meanders: Inferences From The Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Finotello, A.; D'Alpaos, A.; Ghinassi, M.; Lanzoni, S.; Marani, M.; Rinaldo, A.

    2015-12-01

    Meandering channels are ubiquitous features of tidal landscapes. However, despite their fundamental role on the eco-morphodynamic evolution of these landscapes, tidal meanders have received less attention when compared to their fluvial counterparts. Improving current understanding of tidal meander migration, a largely-examined topic in fluvial landscapes, is a key step to highlight analogies and differences between tidal and fluvial cases. The migration of about 400 meander bends, belonging to 40 salt-marsh channels in the Northern Venice Lagoon (Italy), from 1968 to nowadays, has been investigated by means of both a classical method in fluvial frameworks and new procedure. Similarities with fluvial meanders occur, although important difference also emerge. Meanders cutting through the San Felice marsh follow the relationship between cartesian length and channel width, typical of meanders developed within different settings. However, meander migration rates proved to be smaller than those characterizing fluvial meanders. Indeed, the analysis of meander migration suggests a mean migration rate of about 0.10 m/year, consistent with the few data available in the literature. As for the fluvial case, the maximum-potential migration rate (i.e. the envelope curve of the relationship between migration rate and bend radius, both divided by channel width) reaches a maximum for radius-over-width ratio included between 2 and 3, regardless of the considered method. Nevertheless, the new-proposed method allows us to provide a more objective and continuous characterization. By using this new procedure, the channel curvature has finally been Fourier-analyzed, confirming the importance of even harmonics along the curvature spectrum. A correlation between migration rates and dominant harmonics seems to drive the evolution of tidal meanders and might represent a key-feature to distinguish them from their fluvial counterparts.

  19. Tidal Meander Migration: a Case Study from the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    D'Alpaos, A.; Ghinassi, M.; Bellucci, L. G.; Marani, M.

    2014-12-01

    Meandering patterns are universal features of tidal landscapes which exert a great influence on the dynamics of tidal channel networks and on the stratigraphy of intertidal platforms. Despite their importance in landscape evolution and their ubiquity, tidal meanders have received less attention when compared to their fluvial counterparts. Quite a few studies, in fact, have focused on the morphodynamic evolution of tidal meanders, together with their planimetric shape and morphometric characteristics. To improve current understanding of tidal meander migration and its possible stratigraphic implications, we have analyzed a sequence of aerial photographs (from 1938 to present day) for a 20 m in diameter, abandoned tidal meander in the Venice Lagoon, and have carried out high-resolution sedimentological and chronostratigraphical analyses of channel deposits. Aerial photographs before and after the cutoff event have been used to infer a minimum velocity of migration. Well-cores have also been collected along a transect crossing through the neck zone in order to evaluate changes in grain size, sedimentation rates across the cutoff event, and gain further insight into the velocity of migration of meander bends. Spatial distribution of sedimentary facies (pointbar sand, oxbowlake and saltmarsh mud), grain size analyses, and 210 Pb and 137Cs chronometers highlighted that meander cutoff occurred progressively around 60 years ago with a velocity of migration of about 0.5m/year. The effectiveness of the methods and the high spatial and temporal resolution of the data call for further investigations and analyses of the type proposed herein, furthermore highlighting the potentiality of the study area as modern analogue for ancient tidal deposits.

  20. Synthesis and antifungal activity of 6-arylamino-phthalazine-5,8-diones and 6,7-bis(arylthio)-phthalazine-5,8-diones.

    PubMed

    Ryu, Chung-Kyu; Park, Rae-Eun; Ma, Mi-Young; Nho, Ji-Hee

    2007-05-01

    6-Arylamino-phthalazine-5,8-diones and 6,7-bis(arylthio)-phthalazine-5,8-diones were synthesized and tested for in vitro antifungal activity against two pathogenic strains of fungi. Among those tested, many compounds showed good antifungal activity. The results suggest that phthalazine-5,8-diones would be potent antifungal agents.

  1. The Taming of the Jew: "The Merchant of Venice" Is No Laughing Matter

    ERIC Educational Resources Information Center

    Beck, Bernard

    2005-01-01

    A new movie version of Shakespeare's classic troubling comedy, "The Merchant of Venice" (Brokaw, Cowan, Navidi, Piette, & Radford, 2004), has appeared, bringing up an ancient issue of the possible bigotry of the greatest writer in the English language. Shakespeare's plays about minority characters in the Venetian Republic have caused more and more…

  2. Understanding "The Merchant of Venice": A Student Casebook to Issues, Sources, and Historical Documents.

    ERIC Educational Resources Information Center

    Halio, Jay L.

    "The Merchant of Venice," even in its own time, was considered William Shakespeare's most controversial play. Now, one of the most popular read and performed works, the play raises even more important issues for today, particularly anti-Semitism and the treatment of Jews. The analysis of the play in this casebook helps students interpret…

  3. Prejudice, Pedagogy, and the Play: A Study of "The Merchant of Venice."

    ERIC Educational Resources Information Center

    Eiferman, Sharon

    There is little critical agreement on the meaning of Shakespeare's "The Merchant of Venice." One must confront the mindset of the play that systematically dehumanizes, stereotypes, excoriates, and seeks the extermination of one group on the grounds that their existence is repugnant to the controlling majority. Such a mindset is the…

  4. Recent subsidence of the Venice Lagoon from continuous GPS and interferometric synthetic aperture radar

    NASA Astrophysics Data System (ADS)

    Bock, Y.; Wdowinski, S.; Ferretti, A.; Novali, F.; Fumagalli, A.

    2012-03-01

    Coastal regions are increasingly affected by larger storms and rising sea level predicted by global warming models, aggravating the situation in the city of Venice where tidal-induced seasonal flooding coupled with natural and anthropogenic subsidence have been perennial problems. In light of accelerated efforts to protect Venice from the rise in sea level we assess land subsidence in the Venice Lagoon over the last decade. Through a combined analysis of GPS position time series from 2001.55 to 2011.00 for four stations installed by the Magistrato alle Acque di Venezia and thousands of observations of InSAR permanent scatterers using RADARSAT-1 images from 2003.3 to 2007.85, we determine that the northern lagoon subsides at a rate of 2-3 mm/yr, whereas the southern lagoon subsides at 3-4 mm/yr. The city of Venice continues to subside, at a rate of 1-2 mm/yr, in contrast to geodetic studies in the last decade of the 20th Century suggesting that subsidence has been stabilized. The GPS results indicate a general eastward tilt in subsidence and that the natural subsidence rate related to the retreat of the Adriatic plate subducting beneath the Apennines is at least 0.4-0.6 mm/yr. Our combined GPS and InSAR analysis demonstrates high spatial resolution in the vertical direction with a precision of 0.1-0.2 mm/yr with respect to a global reference frame. Continued efforts to secure the city of Venice from flooding must also take into account the significant local and regional subsidence rates as well as the expected rise in sea level.

  5. Development of device therapy for ventricular arrhythmias.

    PubMed

    Holley, Loraine K

    2007-06-01

    The past 25 years have seen the implantable cardioverter defibrillator emerge as the treatment of choice for ventricular arrhythmias with reduction in size but increased therapeutic options. Understanding the complex mechanisms of ventricular arrhythmias and defibrillation in normal and diseased hearts has been the focus of many research teams including that of John Uther at the Westmead Hospital Department of Cardiology. Marked improvements in capacitor and battery technologies, arrhythmia discrimination, pacing algorithms, shock waveforms and monitoring capabilities enable wider use and patient acceptance. Emergence of cardiac resynchronisation therapy and the implantable defibrillator for treatment of chronic heart failure is not only giving quality of life and extended survival for heart failure patients but has also cast new light on the evolution of heart failure.

  6. Sarcolemmal KATP channel modulators and cardiac arrhythmias.

    PubMed

    Baczkó, I; Husti, Z; Lang, V; Leprán, I; Light, P E

    2011-01-01

    Cardiac atrial and ventricular arrhythmias are major causes of mortality and morbidity. Ischemic heart disease is the most common cause underlying 1) the development of ventricular fibrillation that results in sudden cardiac death and 2) atrial fibrillation that can lead to heart failure and stroke. Current pharmacological agents for the treatment of ventricular and atrial arrhythmias exhibit limited effectiveness and many of these agents can cause serious adverse effects - including the provocation of lethal ventricular arrhythmias. Sarcolemmal ATP-sensitive potassium channels (sarcK(ATP)) couple cellular metabolism to membrane excitability in a wide range of tissues. In the heart, sarcK(ATP) are activated during metabolic stress including myocardial ischemia, and both the opening of sarcK(ATP) and mitochondrial K(ATP) channels protect the ischemic myocardium via distinct mechanisms. Myocardial ischemia leads to a series of events that promote the generation of arrhythmia substrate eventually resulting in the development of life-threatening arrhythmias. In this review, the possible mechanisms of the anti- and proarrhythmic effects of sarcK(ATP) modulation as well as the influence of pharmacological K(ATP) modulators are discussed. It is concluded that in spite of the significant advances made in this field, the possible cardiovascular therapeutic utility of current sarcK(ATP) channel modulators is still hampered by the lack of chamber-specific selectivity. However, recent insights into the chamber-specific differences in the molecular composition of sarcKATP in addition to already existing cardioselective sarcK(ATP) channel modulators with sarcK(ATP) isoform selectivity holds the promise for the future development of pharmacological strategies specific for a variety of atrial and ventricular arrhythmias.

  7. Arrhythmias in viral myocarditis and pericarditis.

    PubMed

    Baksi, A John; Kanaganayagam, G Sunthar; Prasad, Sanjay K

    2015-06-01

    Acute viral myocarditis and acute pericarditis are self-limiting conditions that run a benign course and that may not involve symptoms that lead to medical assessment. However, ventricular arrhythmia is frequent in viral myocarditis. Myocarditis is thought to account for a large proportion of sudden cardiac deaths in young people without prior structural heart disease. Identification of acute myocarditis either with or without pericarditis is therefore important. However, therapeutic interventions are limited and nonspecific. Identifying those at greatest risk of a life-threatening arrhythmia is critical to reducing the mortality. This review summarizes current understanding of this challenging area in which many questions remain.

  8. [Effect of anti-arrhythmia drugs on mouse arrhythmia induced by Bufonis Venenum].

    PubMed

    Lu, Wen-juan; Zhou, Jing; Ma, Hong-yue; Lü, Gao-hong; You, Fen-qiang; Ding, An-wei; Duan, Jin-ao

    2011-10-01

    This study is to investigate the effects of phenytoin sodium, lidocaine (sodium channel blockers), propranolol (beta-adrenergic receptor antagonist), amiodarone (drugs prolonging the action potential duration) and verapamil (calcium channel blockers) on arrhythmia of mice induced by Bufonis Venenum (Chansu) and isolated mouse hearts lethal dose of Chansu. Arrhythmia of mice were induced by Chansu and then electrocardiograms (ECGs) were recorded. The changes of P-R interval, QRS complex, Q-T interval, T wave amplitude, heart rate (HR) were observed. Moreover, arrhythmia rate, survival rate and arrhythmia score were counted. Isolated mouse hearts were prefused, and the lethal dose of Chansu was recorded. Compared with control group, after pretreatment with phenytoin sodium, broadening of QRS complex and HR were inhibited, and the incidence of ventricular arrhythmia was reduced dramatically, while survival rate was improved; the isolated mouse hearts lethal dose of Chansu was increased significantly. After pretreatment with lidocaine, the prolongation of P-R interval and broadening of QRS complex were inhibited, and the incidences of ventricular arrhythmia were reduced dramatically, while survival rate was improved; the isolated mouse hearts lethal dose of Chansu was increased significantly. After pretreatment with propranolol, prolongation of P-R interval, broadening of QRS complex, prolongation of Q-T interval and HR were inhibited, and the incidences of both supraventricular and ventricular arrhythmias were reduced dramatically, while survival rate was improved. After pretreatment with amiodarone, HR was inhibited, the incidences of ventricular tachycardia were reduced dramatically. Lastly, after pretreatment with verapamil, the prolongation of P-R interval and Q-T interval were inhibited and the incidences of both supraventricular and ventricular arrhythmias were reduced dramatically; the isolated mouse hearts lethal dose of Chansu was reduced significantly. In in

  9. Cardiac Arrhythmias and Abnormal Electrocardiograms After Acute Stroke.

    PubMed

    Ruthirago, Doungporn; Julayanont, Parunyou; Tantrachoti, Pakpoom; Kim, Jongyeol; Nugent, Kenneth

    2016-01-01

    Cardiac arrhythmias and electrocardiogram (ECG) abnormalities occur frequently but are often underrecognized after strokes. Acute ischemic and hemorrhagic strokes in some particular area of brain can disrupt central autonomic control of the heart, precipitating cardiac arrhythmias, ECG abnormalities, myocardial injury and sometimes sudden death. Identification of high-risk patients after acute stroke is important to arrange appropriate cardiac monitoring and effective management of arrhythmias, and to prevent cardiac morbidity and mortality. More studies are needed to better clarify pathogenesis, localization of areas associated with arrhythmias and practical management of arrhythmias and abnormal ECGs after acute stroke.

  10. Mechanistic and therapeutic perspectives for cardiac arrhythmias: beyond ion channels.

    PubMed

    Wu, Yufei; Li, Jun; Xu, Liang; Lin, Li; Chen, Yi-Han

    2017-03-24

    Cardiac arrhythmias are among the most common causes of death in the world. Foundational studies established the critical role of ion channel disorders in arrhythmias, yet defects in ion channels themselves, such as mutations, may not account for all arrhythmias. Despite the progress made in recent decades, the antiarrhythmic drugs currently available have limited effectiveness, and the majority of these drugs can have proarrhythmic effects. This review describes novel knowledge on cellular mechanisms that cause cardiac arrhythmias, focuses on the dysfunction of subcellular organelles and intracellular logistics, and discusses potential strategies and challenges for developing novel, safe and effective treatments for arrhythmias.

  11. Transcriptomic resources for environmental risk assessment: a case study in the Venice lagoon.

    PubMed

    Milan, M; Pauletto, M; Boffo, L; Carrer, C; Sorrentino, F; Ferrari, G; Pavan, L; Patarnello, T; Bargelloni, L

    2015-02-01

    The development of new resources to evaluate the environmental status is becoming increasingly important representing a key challenge for ocean and coastal management. Recently, the employment of transcriptomics in aquatic toxicology has led to increasing initiatives proposing to integrate eco-toxicogenomics in the evaluation of marine ecosystem health. However, several technical issues need to be addressed before introducing genomics as a reliable tool in regulatory ecotoxicology. The Venice lagoon constitutes an excellent case, in which the assessment of environmental risks derived from the nearby industrial activities represents a crucial task. In this context, the potential role of genomics to assist environmental monitoring was investigated through the definition of reliable gene expression markers associated to chemical contamination in Manila clams, and their subsequent employment for the classification of Venice lagoon areas. Overall, the present study addresses key issues to evaluate the future outlooks of genomics in the environmental monitoring and risk assessment.

  12. Organotins (TBT and DBT) in water, sediments, and gastropods of the southern Venice lagoon (Italy).

    PubMed

    Berto, D; Giani, M; Boscolo, R; Covelli, S; Giovanardi, O; Massironi, M; Grassia, L

    2007-01-01

    The release of tributyltin (TBT) from maritime traffic represents one of the main problems of direct, diffuse, and continued contamination of the marine environment. In the present survey, the concentrations of TBT and dibultytin (DBT) in brackish waters, sediments, and the gastropods Nassarius nitidus were evaluated in order to estimate the contamination of the southern part of the Venice lagoon. TBT and DBT were determined by GC-MS/MS. Recent contamination of TBT was found in brackish waters near marinas, whereas the highest concentrations of TBT and DBT were observed in surface sediments at dockyards and harbours. High content of organotin in the gastropods sampled near the dockyards, harbours, and marinas showed a mobilisation from the sediments through the food web. The present study allowed assessment of whether, despite the ban on the use of TBT paints, waters, sediments, and biota were still being contaminated by organotin compounds in the southern Venice lagoon.

  13. Robotic magnetic navigation for ablation of human arrhythmias

    PubMed Central

    Da Costa, Antoine; Guichard, Jean Baptiste; Roméyer-Bouchard, Cécile; Gerbay, Antoine; Isaaz, Karl

    2016-01-01

    Radiofrequency treatment represents the first choice of treatment for arrhythmias, in particular complex arrhythmias and especially atrial fibrillation, due to the greater benefit/risk ratio compared to antiarrhythmic drugs. However, complex arrhythmias such as atrial fibrillation require long procedures with additional risks such as X-ray exposure or serious complications such as tamponade. Given this context, the treatment of arrhythmias using robotic magnetic navigation entails a technique well suited to complex arrhythmias on account of its efficacy, reliability, significant reduction in X-ray exposure for both patient and operator, as well as a very low risk of perforation. As ongoing developments will likely improve results and procedure times, this technology will become one of the most modern technologies for treating arrhythmias. Based on the literature, this review summarizes the advantages and limitations of robotic magnetic navigation for ablation of human arrhythmias. PMID:27698569

  14. Regional and local land subsidence at the Venice coastland by TerraSAR-X PSI

    NASA Astrophysics Data System (ADS)

    Tosi, L.; Strozzi, T.; Da Lio, C.; Teatini, P.

    2015-11-01

    Land subsidence occurred at the Venice coastland over the 2008-2011 period has been investigated by Persistent Scatterer Interferometry (PSI) using a stack of 90 TerraSAR-X stripmap images with a 3 m resolution and a 11-day revisiting time. The regular X-band SAR acquisitions over more than three years coupled with the very-high image resolution has significantly improved the monitoring of ground displacements at regional and local scales, e.g., the entire lagoon, especially the historical palaces, the MoSE large structures under construction at the lagoon inlets to disconnect the lagoon from the Adriatic Sea during high tides, and single small structures scattered within the lagoon environments. Our results show that subsidence is characterized by a certain variability at the regional scale with superimposed important local displacements. The movements range from a gentle uplift to subsidence rates of up to 35 mm yr-1. For instance, settlements of 30-35 mm yr-1 have been detected at the three lagoon inlets in correspondence of the MoSE works, and local sinking bowls up to 10 mm yr-1 connected with the construction of new large buildings or restoration works have been measured in the Venice and Chioggia historical centers. Focusing on the city of Venice, the mean subsidence of 1.1 ± 1.0 mm yr-1 confirms the general stability of the historical center.

  15. Elemental characterization, sources and wind dependence of PM1 near Venice, Italy

    NASA Astrophysics Data System (ADS)

    Valotto, Gabrio; Squizzato, Stefania; Masiol, Mauro; Zannoni, Daniele; Visin, Flavia; Rampazzo, Giancarlo

    2014-06-01

    In this paper, PM1 elemental composition and relative sources have been investigated near Venice (Eastern Po Valley, Italy). Considering the lack of information on PM1 composition in this area and the general poor knowledge of emission profiles, this study can give useful information to better understand the source profile and the dispersion of finer particles. A sampling campaign was carried out in two sampling sites located inside the "Marco Polo" international airport of Venice. Elemental composition on PM1 samples was characterized by inductively coupled plasma optical emission spectroscopy. Five sources were identified and quantified by using the positive matrix factorization receptor model: heavy oil combustion, road traffic, airplane tire-wear, glassmaking and mixed combustions. The role of local atmospheric circulation was investigated by studying the source contributions as a function of wind velocity. Days characterized by low dispersion (lower wind speed and higher wind calm with respect to full period rose) showed a higher contribution for all sources, and a glassmaking contribution increase linked to wind blowing from South, where the artistic glass district of Venice is located.

  16. Transport of gas-phase polycyclic aromatic hydrocarbons to the Venice lagoon.

    PubMed

    Gambaro, Andrea; Manodori, Laura; Moret, Ivo; Capodaglio, Gabriele; Cescon, Paolo

    2004-10-15

    Concentrations of gas-phase polycyclic aromatic hydrocarbons (PAHs) were studied over one year at two sites of the Venice lagoon (designated Marine and Industrial) and at a mainland station (designated Rural) in Italy. Average sigmaPAH concentrations, calculated as sum of 16 PAHs, at Marine are about three and five times lower than those at Industrial and Rural, respectively. The seasonal trends, the temperature-PAH relationship, and principal component analysis indicate that at Industrial and Marine sites several local sources (vehicle and industrial emissions, etc.) could be the PAH sources in the warmer months, whereas in the colder months the main PAH sources could alternate between vehicle emissions and residential heating. At Rural the main PAH sources are: vehicle emissions in the spring and autumn; vehicle emissions, field burning, and wood combustion in the summer; and vehicle emissions and fuel consumption for residential heating in the winter. To evaluate the contribution from different sources to the Venice Lagoon air, horizontal fluxes of PAHs have been obtained. The estimated annual flux of PAHs is about 9 times greater at Industrial (193.5 mg m(-2) y(-1)) than at Marine (20.6 mg m(-2) y(-1)). These results show that study of the chemical contamination of the Venice atmosphere must take into account the PAH flux derived from marine sources as well as the continental input.

  17. Impact of maritime traffic on polycyclic aromatic hydrocarbons, metals and particulate matter in Venice air.

    PubMed

    Gregoris, Elena; Barbaro, Elena; Morabito, Elisa; Toscano, Giuseppa; Donateo, Antonio; Cesari, Daniela; Contini, Daniele; Gambaro, Andrea

    2016-04-01

    Harbours are important hubs for economic growth in both tourism and commercial activities. They are also an environmental burden being a source of atmospheric pollution often localized near cities and industrial complexes. The aim of this study is to quantify the relative contribution of maritime traffic and harbour activities to atmospheric pollutant concentration in the Venice lagoon. The impact of ship traffic was quantified on various pollutants that are not directly included in the current European legislation for shipping emission reduction: (i) gaseous and particulate PAHs; (ii) metals in PM10; and (iii) PM10 and PM2.5. All contributions were correlated with the tonnage of ships during the sampling periods and results were used to evaluate the impact of the European Directive 2005/33/EC on air quality in Venice comparing measurements taken before and after the application of the Directive (year 2010). The outcomes suggest that legislation on ship traffic, which focused on the issue of the emissions of sulphur oxides, could be an efficient method also to reduce the impact of shipping on primary particulate matter concentration; on the other hand, we did not observe a significant reduction in the contribution of ship traffic and harbour activities to particulate PAHs and metals. Graphical abstract Impact of maritime traffic on polycyclic aromatic hydrocarbons, metals and particulate matter and evaluation of the effect of an European Directive on air quality in Venice.

  18. Haemodynamic assessment of fetal heart arrhythmias.

    PubMed

    Lingman, G; Dahlström, J A; Eik-Nes, S H; Marsál, K; Ohlin, P; Ohrlander, S

    1984-07-01

    The effects of fetal heart arrhythmias were examined serially in two pregnancies by three non-invasive methods: fetal ECG, fetal phonocardiography and ultrasonic measurement of fetal blood flow. In a case of supraventricular arrhythmia, there was evidence suggesting that the stroke volume varied with ventricular filling according to the Frank-Starling law. In a case of total atrioventricular block the mean blood flow in the fetal descending aorta and in the umbilical vein was within the normal range. Blood flow velocity in the inferior vena cava of the fetus reflected atrial contractions. In the phonocardiogram, a phenomenon similar to 'bruit de canon' was found. Both pregnancies had good outcomes and subsequent development of the infants was normal except for the persisting dysrhythmias. The two cases exemplify how fetal heart function can be assessed in utero.

  19. [Compromized myocardial perfusion in arrhythmias (author's transl)].

    PubMed

    Simon, H; Neumann, G; Felix, R; Hedde, H; Schaede, A; Thurn, P; Winkler, C

    1977-09-15

    In 7 patients with arrhythmias of various origin the myocardial scintigram displayed either a diffuse or circumscript defect of the perfusion. The coronary arteriogram was normal in all patients. The localized defect of the perfusion in 2 patients was in the region of the upper part of the interventricular septum. Both had a left bundle brunch block. A correlation between the perfusion defect and the electrophysiological abnormality seems probable. The perfusion defect in one of the patients is most probably caused by a previous myocarditis followed by fibrous changes. In the other 6 patients the cause for the perfusion defect is not obvious. A history of myocarditis is missing. The presence of "small vessel disease" in those patients has however to be considered. Our results point to the relation between an abnormality of the microcirculation and arrhythmias in younger patients.

  20. Progressive interatrial block and supraventricular arrhythmias.

    PubMed

    Enriquez, Andres; Conde, Diego; Redfearn, Damian P; Baranchuk, Adrian

    2015-07-01

    Interatrial conduction disorders are frequent in patients with structural heart diseases, including hypertension, coronary disease, and hypertrophic cardiomyopathy, and they are strongly associated with atrial tachyarrhythmias, especially atrial fibrillation and flutter. Conduction delays lead to dispersion of refractory periods and participate in initiating and maintaining reentry circuits, facilitating atrial arrhythmias. In this case, the changing pattern over time is a manifestation of progressive atrial remodeling and conduction delay. The terminal negative component of the P wave in the inferior leads suggests block of the electrical impulse in the Bachman bundle zone, with retrograde activation of the left atria via muscular connections at the coronary sinus. This has been reproduced in experimental models and confirmed by endocardial mapping. Physicians should be aware of the association between advanced interatrial block and development of atrial arrhythmias as its recognition could prompt early and aggressive antiarrhythmic treatment.

  1. Genetics of inherited primary arrhythmia disorders

    PubMed Central

    Spears, Danna A; Gollob, Michael H

    2015-01-01

    A sudden unexplained death is felt to be due to a primary arrhythmic disorder when no structural heart disease is found on autopsy, and there is no preceding documentation of heart disease. In these cases, death is presumed to be secondary to a lethal and potentially heritable abnormality of cardiac ion channel function. These channelopathies include congenital long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, and short QT syndrome. In certain cases, genetic testing may have an important role in supporting a diagnosis of a primary arrhythmia disorder, and can also provide prognostic information, but by far the greatest strength of genetic testing lies in the screening of family members, who may be at risk. The purpose of this review is to describe the basic genetic and molecular pathophysiology of the primary inherited arrhythmia disorders, and to outline a rational approach to genetic testing, management, and family screening. PMID:26425105

  2. Non-invasive Mapping of Cardiac Arrhythmias.

    PubMed

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome).

  3. Diagnosis and Treatment of Fetal Arrhythmia

    PubMed Central

    Wacker-Gussmann, Annette; Strasburger, Janette F.; Cuneo, Bettina F.; Wakai, Ronald T.

    2014-01-01

    Detection and careful stratification of fetal heart rate (FHR) is extremely important in all pregnancies. The most lethal cardiac rhythm disturbances occur during apparently normal pregnancies where FHR and rhythmare regular and within normal or low-normal ranges. These hidden depolarization and repolarization abnormalities, associated with genetic ion channelopathies cannot be detected by echocardiography, and may be responsible for up to 10% of unexplained fetal demise, prompting a need for newer and better fetal diagnostic techniques. Other manifest fetal arrhythmias such as premature beats, tachycardia, and bradycardia are commonly recognized. Heart rhythm diagnosis in obstetrical practice is usually made by M-mode and pulsed Doppler fetal echocardiography, but not all fetal cardiac time intervals are captured by echocardiographic methods. This article reviews different types of fetal arrhythmias, their presentation and treatment strategies, and gives an overview of the present and future diagnostic techniques. PMID:24858320

  4. Malignant ventricular arrhythmias in chronic chagasic myocarditis.

    PubMed

    Chiale, P A; Halpern, M S; Nau, G J; Przybylski, J; Tambussi, A M; Lázzari, J O; Elizari, M V; Rosenbaum, M B

    1982-03-01

    We studied 28 cases of chronic chagasic myocarditis (CCM) with frequent ventricular arrhythmias. Two-hundred and three conventional ECGs recorded during 3 months showed ventricular extrasystoles (VE) ranging between 0.2 and 6 per ten beats in 100%; multiform VE in 97.04%; couplets in 79.31%; ventricular tachycardia (VT) in 42.85%; and R on T in 21.67%. A 24-hour continuous recording showed that VE ranged between 3780 and 61733 (mean 16618 +/- 2627); multiform VE and couplets were present in 100% of patients, and VT was present in 78.5%. In 16 patients (group I) the frequency of VE was persistently high, without diurnal variation; 11 patients showed sustained reduction during sleeping hours and only one showed an increase during night sleep (group II). Even in group II, VE never disappeared for periods longer than 10 minutes. In five patients, four 24-hour recordings were obtained at weekly intervals, and in five other patients a second 24-hour recording was performed 10 to 24 months later. The remarkable frequency, persistence and low variability of ventricular arrhythmias in CCM suggest that such arrhythmias can be used as a most stable, reliable, but highly demanding model for testing the efficacy of antiarrhythmic drugs.

  5. Prophylactic arrhythmia surgery in association with congenital heart disease.

    PubMed

    Mavroudis, Constantine; Deal, Barbara J

    2016-07-01

    Certain congenital heart anomalies make patients more susceptible to arrhythmia development throughout their lives. This poses the question whether prophylactic arrhythmia surgery should be incorporated into reparative open heart procedures for congenital heart disease. There is currently no consensus on what constitutes a standard prophylactic procedure, owing to the questions that remain regarding lesions to be performed; energy sources to use; proximity of energy source or incisions to coronary arteries, sinoatrial node, atrioventricular node; circumstances for right atrial, left atrial, or biatrial appendectomy; and whether to perform a right, left, or biatrial maze procedure. These considerations are important because prophylactic arrhythmia procedures are performed without knowing if the patient will actually develop an arrhythmia in his or her lifetime. By reviewing and summarizing the literature, congenital heart disease patients who are at risk for developing atrial arrhythmias can be identified and lesion sets can be suggested in an effort to standardize experimental protocols for prophylactic arrhythmia surgery.

  6. Pharmacotherapy of cardiac arrhythmias--basic science for clinicians.

    PubMed

    Shu, Juan; Zhou, Jun; Patel, Chinmay; Yan, Gan-Xin

    2009-11-01

    Cardiac arrhythmias occur in approximately 5.3% of the population and contribute substantially to morbidity and mortality. Pharmacological therapy still remains the major approach in management of patients with nearly every form of cardiac arrhythmia. Effective and safe management of cardiac arrhythmias with antiarrhythmic drugs requires understanding of basic mechanisms for various cardiac arrhythmias, clinical diagnosis of an arrhythmia and identification of underlying cardiac diseases, pharmacokinetics, and antiarrhythmic properties of each individual antiarrhythmic drug. Most cardiac arrhythmias occur via one of the two mechanisms: abnormal impulse formation and reentry or both. Antiarrhythmic drugs primarily work via influencing cardiac automaticity or triggered activity or by their effects on effective refractoriness of cardiac cells. Proarrhythmic effects of antiarrhythmic drugs are also briefly discussed in this review article.

  7. Prophylactic arrhythmia surgery in association with congenital heart disease

    PubMed Central

    Deal, Barbara J.

    2016-01-01

    Certain congenital heart anomalies make patients more susceptible to arrhythmia development throughout their lives. This poses the question whether prophylactic arrhythmia surgery should be incorporated into reparative open heart procedures for congenital heart disease. There is currently no consensus on what constitutes a standard prophylactic procedure, owing to the questions that remain regarding lesions to be performed; energy sources to use; proximity of energy source or incisions to coronary arteries, sinoatrial node, atrioventricular node; circumstances for right atrial, left atrial, or biatrial appendectomy; and whether to perform a right, left, or biatrial maze procedure. These considerations are important because prophylactic arrhythmia procedures are performed without knowing if the patient will actually develop an arrhythmia in his or her lifetime. By reviewing and summarizing the literature, congenital heart disease patients who are at risk for developing atrial arrhythmias can be identified and lesion sets can be suggested in an effort to standardize experimental protocols for prophylactic arrhythmia surgery. PMID:27709096

  8. Basic Cardiac Electrophysiology and Common Drug-induced Arrhythmias.

    PubMed

    Lee, Aimee; Pickham, David

    2016-09-01

    Drugs can be a double-edged sword, providing the benefit of symptom alleviation and disease modification but potentially causing harm from adverse cardiac arrhythmic events. Proarrhythmia is the ability of a drug to cause an arrhythmia, the number one reason for drugs to be withdrawn from the patient. Drug-induced arrhythmias are defined as the production of de novo arrhythmias or aggravation of existing arrhythmias, as a result of previous or concomitant pharmacologic treatment. This review summarizes normal cardiac cell and tissue functioning and provides an overview of drugs that effect cardiac repolarization and the adverse effects of commonly administered antiarrhythmics.

  9. Arrhythmias in the setting of hematopoietic cell transplants.

    PubMed

    Tonorezos, E S; Stillwell, E E; Calloway, J J; Glew, T; Wessler, J D; Rebolledo, B J; Pham, A; Steingart, R M; Lazarus, H; Gale, R P; Jakubowski, A A; Schaffer, W L

    2015-09-01

    Prior studies report that 9-27% of persons receiving a hematopoietic cell transplant develop arrhythmias, but the effect on outcomes is largely unknown. We reviewed data from 1177 consecutive patients ⩾40 years old receiving a hematopoietic cell transplant at one center during 1999-2009. Transplant indication was predominately leukemia, lymphoma and multiple myeloma. Overall, 104 patients were found to have clinically significant arrhythmia: 43 before and 61 after transplant. Post-transplant arrhythmias were most frequently atrial fibrillation (N=30), atrial flutter (N=7) and supraventricular tachycardia (N=11). Subjects with an arrhythmia post transplant were more likely to have longer median hospital stays (32 days vs 23, P=<0.001), a greater probability of an intensive care unit admission (52% vs 7%; P<0.001), greater probability of in-hospital deaths (28% vs 3%, P<0.001), and greater probability of death within 1 year of transplant (41% vs 15%; P<0.001) compared with patients without arrhythmia at any time. In a multivariate model including age at transplant, diagnosis, history of pretransplant arrhythmia, and transplant-related variables, post-transplant arrhythmia was associated with a greater risk for death within a year of transplant (odds ratio 3.5, 95% confidence interval: 2.1, 5.9; P<0.001). Our data suggest that arrhythmias after transplants are associated with significant morbidity and mortality. A prospective study of arrhythmia in the transplant setting is warranted.

  10. Current treatment of ventricular arrhythmias: state of the art.

    PubMed

    Stevenson, William G

    2013-12-01

    Ventricular arrhythmias may be benign, requiring only evaluation for associated risks and then reassurance, or associated with a risk of sudden death or significant morbidity. Therapies for these arrhythmias have evolved considerably over the past 20 years. For some, a definitive, curative therapy is available in the form of catheter ablation. Others are best managed with an implantable cardioverter-defibrillator that provides effective arrhythmia termination and protection from sudden death, with antiarrhythmic drugs or ablation to control recurrent arrhythmias. Although progress has been substantial, many challenges remain.

  11. Cardiac arrhythmias in Chagas' heart disease.

    PubMed

    Elizari, M V; Chiale, P A

    1993-10-01

    Chagas' disease is a chronic parasitosis affecting most Latin American countries. Its most important clinical manifestation is a late developing chronic myocarditis and, much less frequently, an early acute myocarditis. Chagasic myocardial damage is microfocal and disseminated throughout the heart. In most cases, the coexistence of areas of myocytic degeneration, inflammatory infiltration, and fibrosis suggests a permanent evolving process. Commonly, chronic chagasic myocarditis resembles a dilated cardiomyopathy, with characteristic ECG abnormalities (atrial and ventricular extrasystoles, intraventricular and/or AV conduction disturbances, and primary ST-T wave changes). Since myocardial damage is scattered throughout the heart, the ECG abnormalities (arrhythmias, conduction disturbances, and repolarization changes) are also representative of the widespread cardiac involvement. Thus, sick sinus syndrome, atrial extrasystoles, intraatrial conduction disturbances, and atrial fibrillation or flutter are common findings in different stages of the disease. At the ventricular level, both conduction disturbances and arrhythmias are conspicuous expressions of the myocardial damage. Right bundle branch block alone or in combination with left anterior hemiblock are the most common conduction defects. Further compromise of the conduction system can lead to different degrees of AV block. Chagas' disease is the main cause of bundle branch block and AV block in endemic areas. In advanced cases of Chagas' heart disease, ventricular premature contractions are extremely frequent, multiform, and repetitive (couplets and runs of ventricular tachycardia), and show R on T phenomenon. These arrhythmias are usually aggravated by increased sympathetic tone, implying an enhanced risk of cardiac sudden death among chagasic patients, which is sometimes the first manifestation of the illness. Chronic chagasic myocarditis is the leading cause of cardiovascular death, mostly as a consequence

  12. 44 CFR 5.8 - Records involved in litigation or other judicial process.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Records involved in litigation or other judicial process. 5.8 Section 5.8 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY GENERAL PRODUCTION OR DISCLOSURE OF INFORMATION...

  13. An Analysis of Large-Scale Writing Assessments in Canada (Grades 5-8)

    ERIC Educational Resources Information Center

    Peterson, Shelley Stagg; McClay, Jill; Main, Kristin

    2011-01-01

    This paper reports on an analysis of large-scale assessments of Grades 5-8 students' writing across 10 provinces and 2 territories in Canada. Theory, classroom practice, and the contributions and constraints of large-scale writing assessment are brought together with a focus on Grades 5-8 writing in order to provide both a broad view of…

  14. Distribution of Sediment and Benthic Foraminifera in the Gulf of Venice, Italy

    NASA Astrophysics Data System (ADS)

    Albani, A. D.; Favero, V. M.; Serandrei Barbero, R.

    1998-02-01

    Sedimentary provinces and foraminiferal biotopes from the Gulf of Venice, northern Adriatic, have been determined based on 174 sampling sites. The sediment distribution is primarily due to longshore transport. The foraminiferal biotopes are largely controlled by the interaction between the marine and lagoonal water masses. The distributions of benthic foraminifera and sedimentary provinces do not correlate directly, but sediments and foraminifera reflect the characteristics and behaviour of the water masses. Areas of dumped industrial solid wastes show no effect on the distribution of benthic foraminiferal assemblages which are influenced primarily by water quality.

  15. A Vision of Venice in the next Fin-de-Siècle

    NASA Astrophysics Data System (ADS)

    Tagliapietra, Davide

    2014-05-01

    The IPCC's Fifth Assessment Report projections of sea level rise are larger than in the previous one. In the Adriatic a sea level rise higher than 60 cm is considered possible and rise of one meter cannot be excluded. An end-of-century a scenario in which the mobile barrier at the inlets will not be sufficient to protect the City of Venice from permanent floods is realistic and the closure of the lagoon will become inevitable. The possibility of converting the lagoon of Venice in an enclosed non-tidal basin is discussed. The aim is to protect the City preserving as much as possible the features of a healthy brackish ecosystem able to provide many of the ecosystem services it provides at present. This involves technological challenges, a deeper understanding of the ecological functioning of enclosed coastal basins, and last but not least, a shift in the educational and cultural paradigms. There is the need to endorse a coordinated and large-scale research effort to understand what will be the new hydrology and ecohydrology of the lagoon. The relationship between ecosystem metabolism and hydrology should be approached in the conceptual framework of lagoonal saprobity. Ad hoc research programs with experimental studies and observational monitoring should be implemented to improve our understanding of new ecological scenarios. Among the new opportunities arising from an heavy hydrological management there is the possibility to keep the water at an optimum level for the fruition of the City as it was a few centuries ago. It is likely that the sea level rise would change the entire geographical context. Brackish and freshwater wetlands surrounding the lagoon of Venice, reclaimed during the last century, will be probably ingressed by the sea. An attentive adaptive policy of wetland re-creation could supply both the ecological functions and the ecosystem services lost by the lagoon of Venice. The rapid adoption of a long-term strategy is therefore needed. Strategies should

  16. Heart-brain interactions in cardiac arrhythmia.

    PubMed

    Taggart, P; Critchley, H; Lambiase, P D

    2011-05-01

    This review examines current knowledge of the effects of higher brain centres and autonomic control loops on the heart with particular relevance to arrhythmogenesis. There is now substantial evidence that higher brain function (cortex), the brain stem and autonomic nerves affect cardiac electrophysiology and arrhythmia, and that these may function as an interactive system. The roles of mental stress and emotion in arrhythmogenesis and sudden cardiac death are no longer confined to the realms of anecdote. Advances in molecular cardiology have identified cardiac cellular ion channel mutations conferring vulnerability to arrhythmic death at the myocardial level. Indeed, specific channelopathies such as long QT syndrome and Brugada syndrome are selectively sensitive to either sympathetic or vagal stimulation. There is increasing evidence that afferent feedback from the heart to the higher centres may affect efferent input to the heart and modulate the cardiac electrophysiology. The new era of functional neuroimaging has identified the central neural circuitry in this brain-heart axis. Since precipitants of sudden fatal arrhythmia are frequently environmental and behavioural, central pathways translating stress into autonomic effects on the heart might be considered as therapeutic targets. These brain-heart interactions help explain the apparent randomness of sudden cardiac events and provide new insights into future novel therapies to prevent sudden death.

  17. Acute emotional stress and cardiac arrhythmias.

    PubMed

    Ziegelstein, Roy C

    2007-07-18

    Episodes of acute emotional stress can have significant adverse effects on the heart. Acute emotional stress can produce left ventricular contractile dysfunction, myocardial ischemia, or disturbances of cardiac rhythm. Although these abnormalities are often only transient, their consequences can be gravely damaging and sometimes fatal. Despite the many descriptions of catastrophic cardiovascular events in the setting of acute emotional stress, the anatomical substrate and physiological pathways by which emotional stress triggers cardiovascular events are only now being characterized, aided by the advent of functional neuroimaging. Recent evidence indicates that asymmetric brain activity is particularly important in making the heart more susceptible to ventricular arrhythmias. Lateralization of cerebral activity during emotional stress may stimulate the heart asymmetrically and produce areas of inhomogeneous repolarization that create electrical instability and facilitate the development of cardiac arrhythmias. Patients with ischemic heart disease who survive an episode of sudden cardiac death in the setting of acute emotional stress should receive a beta-blocker. Nonpharmacological approaches to manage emotional stress in patients with and without coronary artery disease, including social support, relaxation therapy, yoga, meditation, controlled slow breathing, and biofeedback, are also appropriate to consider and merit additional investigation in randomized trials.

  18. Cancer chemotherapy and cardiac arrhythmias: a review.

    PubMed

    Tamargo, Juan; Caballero, Ricardo; Delpón, Eva

    2015-02-01

    Cardiovascular toxicity is a potential complication of cancer chemotherapy (CC) that increases the morbidity and mortality of cancer patients. Cardiac arrhythmias have been reported as an adverse effect of many chemotherapeutic drugs, including novel targeted therapies. The relationship between chemotherapy and arrhythmias has not been well-established and the proarrhythmogenic mechanisms remain uncertain as they can be the result of a direct electrophysiological effect or of changes in cardiac structure and function, including myocardial ischaemia and heart failure, which create an arrhythmogenic substrate. In this review we summarise available evidence of proarrhythmia induced by CC, discuss the possible mechanisms involved in this adverse effect and emphasise the importance of cardiac monitoring for the early diagnosis, intervention and surveillance of those patients more susceptible to develop proarrhythmia in an attempt to reduce the morbidity and mortality. Oncologists should be fully aware of proarrhythmia and the close collaboration between cardiologists and oncologists would result in a better cardiovascular assessment, risk stratification, cardiac monitoring and treatment during CC and during the follow-up. The final objective is to understand the mechanisms of proarrhythmia and evaluate its real incidence and clinical relevance so as to select the safest and most effective treatment for cancer patients.

  19. Almanac 2013: cardiac arrhythmias and pacing.

    PubMed

    Liew, Reginald

    2013-10-01

    Important advances have been made in the past few years in the fields of clinical cardiac electrophysiology and pacing. Researchers and clinicians have a greater understanding of the pathophysiological mechanisms underlying atrial fibrillation (AF), which has transpired into improved methods of detection, risk stratification, and treatments. The introduction of novel oral anticoagulants has provided clinicians with alternative options in managing patients with AF at moderate to high thromboembolic risk and further data has been emerging on the use of catheter ablation for the treatment of symptomatic AF. Another area of intense research in the field of cardiac arrhythmias and pacing is in the use of cardiac resynchronisation therapy (CRT) for the treatment of patients with heart failure. Following the publication of major landmark randomised controlled trials reporting that CRT confers a survival advantage in patients with severe heart failure and improves symptoms, many subsequent studies have been performed to further refine the selection of patients for CRT and determine the clinical characteristics associated with a favourable response. The field of sudden cardiac death and implantable cardioverter defibrillators also continues to be actively researched, with important new epidemiological and clinical data emerging on improved methods for patient selection, risk stratification, and management. This review covers the major recent advances in these areas related to cardiac arrhythmias and pacing.

  20. Fetal Arrhythmias Associated with Cardiac Rhabdomyomas

    PubMed Central

    Wacker-Gussmann, Annette; Strasburger, Janette F; Cuneo, Bettina; Wiggins, Delonia; Gotteiner, Nina; Wakai, Ronald T

    2014-01-01

    Background Primary heart tumors in fetuses are rare and mainly represent rhabdomyomas. The tumors have a variable expression and can be associated with arrhythmias, including both wide and narrow QRS tachycardia. Although multiple Doppler techniques exist to assess fetal heart rhythm, it can be difficult to record precise electrophysiological pathologies in fetal life. Objective Investigations defining precise electrophysiological diagnosis were performed using fetal magnetocardiography (fMCG). Methods In addition to routine fetal echocardiography, fMCG was used to investigate electrophysiologic rhythm patterns in a series of 10 fetuses with cardiac rhabdomyomas. Results The mean gestational age of the fetuses was 28.6 weeks (SD ± 4.7 weeks). The multiple rhabdomyomas were mainly located in the right and left ventricles as well as around the AV groove. Arrhythmias or conduction abnormalities were diagnosed in all 10 patients, although only six of them were referred due to that indication. Remarkably, 80% (8/10) had associated Wolff-Parkinson-White pre-excitation. In addition, we found prominent p waves in four fetuses. Conclusion In fetuses with rhabdomyomas, a disease where rhythm pathology is common, precise electrophysiological diagnosis can now be made by fMCG. fMCG is complimentary to echocardiography for rhythm assessment, and can detect conduction abnormalities that are not possible to diagnose prenatally with M-mode or pulsed Doppler ultrasound. Risk factor assessment using fMCG can support pregnancy management and post-natal treatment and follow-up. PMID:24333285

  1. Atrial Arrhythmias and Their Implications for Space Flight - Introduction

    NASA Technical Reports Server (NTRS)

    Polk, J. D.; Barr, Y. R.; Bauer, P.; Hamilton, D. R.; Kerstman, E.; Tarver, B.

    2010-01-01

    This panel will discuss the implications of atrial arrhythmias in astronauts from a variety of perspectives; including historical data, current practices, and future challenges for exploration class missions. The panelists will present case histories, outline the evolution of current NASA medical standards for atrial arrhythmias, discuss the use of predictive tools, and consider potential challenges for current and future missions.

  2. Neuroanatomical correlates of severe cardiac arrhythmias in acute ischemic stroke.

    PubMed

    Seifert, Frank; Kallmünzer, Bernd; Gutjahr, Isabell; Breuer, Lorenz; Winder, Klemens; Kaschka, Iris; Kloska, Stephan; Doerfler, Arnd; Hilz, Max-Josef; Schwab, Stefan; Köhrmann, Martin

    2015-05-01

    Neurocardiological interactions can cause severe cardiac arrhythmias in patients with acute ischemic stroke. The relationship between the lesion location in the brain and the occurrence of cardiac arrhythmias is still discussed controversially. The aim of the present study was to correlate the lesion location with the occurrence of cardiac arrhythmias in patients with acute ischemic stroke. Cardiac arrhythmias were systematically assessed in patients with acute ischemic stroke during the first 72 h after admission to a monitored stroke unit. Voxel-based lesion-symptom mapping (VLSM) was used to correlate the lesion location with the occurrence of clinically relevant severe arrhythmias. Overall 150 patients, 56 with right-hemispheric and 94 patients with a left-hemispheric lesion, were eligible to be included in the VLSM study. Severe cardiac arrhythmias were present in 49 of these 150 patients (32.7%). We found a significant association (FDR correction, q < 0.05) between lesions in the right insular, right frontal and right parietal cortex as well as the right amygdala, basal ganglia and thalamus and the occurrence of cardiac arrhythmias. Because left- and right-hemispheric lesions were analyzed separately, the significant findings rely on the 56 patients with right-hemispheric lesions. The data indicate that these areas are involved in central autonomic processing and that right-hemispheric lesions located to these areas are associated with an elevated risk for severe cardiac arrhythmias.

  3. Psychophysiological factors in ventricular arrhythmias and sudden cardiac death.

    PubMed

    Hatton, D C; Gilden, E R; Edwards, M E; Cutler, J; Kron, J; McAnulty, J H

    1989-01-01

    Plasma catecholamine levels were measured preceding programmed electrophysiological studies of patients who had survived a ventricular tachyarrhythmia episode. Psychological assessments of desire for control, locus of control and behavior pattern were obtained. Psychophysiological variables were analysed with respect to the severity of arrhythmias induced by the electrophysiological procedure. Analysis of data from 17 subjects showed desire for control was significantly higher in those with induced sustained arrhythmias than in those in which nonsustained arrhythmias were induced. No relationship was found between behavior pattern and arrhythmia severity or plasma catecholamine levels. There was a significant interaction between desire for control and behavior pattern with respect to epinephrine level. The findings indicate that psychological factors such as desire for control may be associated with potentially lethal arrhythmias and implicated in sudden cardiac death.

  4. Altered Calcium Handling and Ventricular Arrhythmias in Acute Ischemia

    PubMed Central

    Baumeister, Peter; Quinn, T. Alexander

    2016-01-01

    Acute ischemia results in deadly cardiac arrhythmias that are a major contributor to sudden cardiac death (SCD). The electrophysiological changes involved have been extensively studied, yet the mechanisms of ventricular arrhythmias during acute ischemia remain unclear. What is known is that during acute ischemia both focal (ectopic excitation) and nonfocal (reentry) arrhythmias occur, due to an interaction of altered electrical, mechanical, and biochemical properties of the myocardium. There is particular interest in the role that alterations in intracellular calcium handling, which cause changes in intracellular calcium concentration and to the calcium transient, play in ischemia-induced arrhythmias. In this review, we briefly summarize the known contributors to ventricular arrhythmias during acute ischemia, followed by an in-depth examination of the potential contribution of altered intracellular calcium handling, which may include novel targets for antiarrhythmic therapy. PMID:28008297

  5. Perspective: a dynamics-based classification of ventricular arrhythmias.

    PubMed

    Weiss, James N; Garfinkel, Alan; Karagueuzian, Hrayr S; Nguyen, Thao P; Olcese, Riccardo; Chen, Peng-Sheng; Qu, Zhilin

    2015-05-01

    Despite key advances in the clinical management of life-threatening ventricular arrhythmias, culminating with the development of implantable cardioverter-defibrillators and catheter ablation techniques, pharmacologic/biologic therapeutics have lagged behind. The fundamental issue is that biological targets are molecular factors. Diseases, however, represent emergent properties at the scale of the organism that result from dynamic interactions between multiple constantly changing molecular factors. For a pharmacologic/biologic therapy to be effective, it must target the dynamic processes that underlie the disease. Here we propose a classification of ventricular arrhythmias that is based on our current understanding of the dynamics occurring at the subcellular, cellular, tissue and organism scales, which cause arrhythmias by simultaneously generating arrhythmia triggers and exacerbating tissue vulnerability. The goal is to create a framework that systematically links these key dynamic factors together with fixed factors (structural and electrophysiological heterogeneity) synergistically promoting electrical dispersion and increased arrhythmia risk to molecular factors that can serve as biological targets. We classify ventricular arrhythmias into three primary dynamic categories related generally to unstable Ca cycling, reduced repolarization, and excess repolarization, respectively. The clinical syndromes, arrhythmia mechanisms, dynamic factors and what is known about their molecular counterparts are discussed. Based on this framework, we propose a computational-experimental strategy for exploring the links between molecular factors, fixed factors and dynamic factors that underlie life-threatening ventricular arrhythmias. The ultimate objective is to facilitate drug development by creating an in silico platform to evaluate and predict comprehensively how molecular interventions affect not only a single targeted arrhythmia, but all primary arrhythmia dynamics

  6. Biologically-controlled multiple equilibria of tidal landforms and the fate of the Venice lagoon

    NASA Astrophysics Data System (ADS)

    Marani, Marco; D'Alpaos, Andrea; Lanzoni, Stefano; Carniello, Luca; Rinaldo, Andrea

    2007-06-01

    Looking across a tidal landscape, can one foresee the signs of impending shifts among different geomorphological structures? This is a question of paramount importance considering the ecological, cultural and socio-economic relevance of tidal environments and their worldwide decline. In this Letter we argue affirmatively by introducing a model of the coupled tidal physical and biological processes. Multiple equilibria, and transitions among them, appear in the evolutionary dynamics of tidal landforms. Vegetation type, disturbances of the benthic biofilm, sediment availability and marine transgressions or regressions drive the bio-geomorphic evolution of the system. Our approach provides general quantitative routes to model the fate of tidal landforms, which we illustrate in the case of the Venice lagoon (Italy), for which a large body of empirical observations exists spanning at least five centuries. Such observations are reproduced by the model, which also predicts that salt marshes in the Venice lagoon may not survive climatic changes in the next century if IPCC's scenarios of high relative sea level rise occur.

  7. Mercury in sediments and Nassarius reticulatus (Gastropoda Prosobranchia) in the southern Venice Lagoon.

    PubMed

    Berto, D; Giani, M; Covelli, S; Boscolo, R; Cornello, M; Macchia, S; Massironi, M

    2006-09-01

    The southern basin of the Venice Lagoon has been the focus of fewer studies concerning contamination from heavy metals than the northern and central basins. A recent increase in urban waste waters from Chioggia town, as well as dockyards, shipping and fishing activities, affect this part of the lagoon. The aim of this study was to investigate the total mercury (THg) incidence in sediments and Nassarius reticulatus gastropods in order to assess its distribution and evaluate the level of contamination. THg concentration measured in bottom sediments ranged between 0.1 and 3.4 mg/kg d. wt. The enrichment factor (EF) showed high values (avg. 30, max 49) near the dockyards of Chioggia; the lowest (avg. 9, max 17) were found in the coastal marine sediments near the port entrance of the southern basin. THg in marine scavenger gastropods accumulated in N. reticulatus with concentrations falling within the range of 0.3-1.3 mg/kg d. wt. A positive correlation was found between THg concentration in sediments and in N. reticulatus in all sites, excluding the dockyards. A first local cause for mercury pollution might be attributed to the antifouling paints used in great quantity in the recent past near the town of Chioggia. Moreover, fine suspended sediments associated with tidal flushing are suggested as possibly being the vehicle for pollutant dispersal from the Marghera industrial area to the whole of Venice's lagoon.

  8. Organic micropollutants in wet and dry depositions in the Venice Lagoon.

    PubMed

    Gambaro, Andrea; Radaelli, Marta; Piazza, Rossano; Stortini, Angela Maria; Contini, Daniele; Belosi, Franco; Zangrando, Roberta; Cescon, Paolo

    2009-08-01

    Atmospheric transport is an important route by which pollutants are conveyed from the continents to both coastal and open sea. The role of aerosol deposition in the transport of polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs) and polybromodiphenyls ethers (PBDEs) to water and soil systems has been evaluated by measuring their concentrations in wet and dry depositions to the Venice Lagoon. The organic micropollutant flux data indicate that they contribute to the total deposition flux in different ways through wet and dry deposition, showing that the prevalent contribution derives from wet deposition. The fluxes calculated for PBDEs, showed the prevalence of 47, 99, 100 and 183 congeners, both in dry and wet fluxes. With regard to PCBs, the flux of summation operatorPCB for wet deposition is in the same order of magnitude of the diffusive flux at the air-water interface. The PAH fluxes obtained in the present study are similar to those obtained in previous studies on the atmospheric bulk deposition to the Venice Lagoon. The ratios between Phe/Ant and Fl/Py indicate that the pollutants sources are pyrolytic, deriving from combustion fuels.

  9. Processable, high temperature polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and bis-dienes

    NASA Technical Reports Server (NTRS)

    Meador, Mary Ann B.

    1988-01-01

    1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene reacts with various anthracene end-capped polyimide oligomers to form Diels-Alder cycloaddition copolymers. The polymers are soluble in common organic solvents, and have molecular weights of approximately 21,000 to 32,000. These resins exhibit lower weight loss in air than in nitrogen. This is suggested to be due to dehydration (loss of water ranges from 2 to 5 percent) at temperatures of 390 to 400 C to give thermooxidatively stable pentiptycene units along the polymer backbone. Because of their high softening points and good thermooxidative stability, the polymers have potential as processable, matrix resins for high temperature composite applications.

  10. Addition polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and Bis-dienes: Processable resins for high temperature application

    NASA Technical Reports Server (NTRS)

    Meador, Mary Ann B.

    1987-01-01

    1,4,5,8-Tetrahydro-1,4;5,8-diepoxyanthracene reacts with various anthracene endcapped polyimide oligomers to form Diels-Alder cycloaddition copolymers. The polymers are soluble in common organic solvents, and have molecular weights of approximately 21,000 to 32,000. Interestingly, these resins appear to be more stable in air then in nitrogen. This is shown to be due to a unique dehydration (loss of water ranges from 2 to 5 percent) at temperatures of 390 to 400 C to give thermo-oxidatively stable pentiptycene units along the polymer backbone. Because of their high softening points and good thermo-oxidative stability, the polymers have potential as processible, matrix resins for high temperature composite applications.

  11. Physiological measurements from native and transplanted mussel (Mytilus galloprovincialis) in the canals of Venice. Survival in air and condition index.

    PubMed

    Pampanin, Daniela M; Volpato, Elisa; Marangon, Ilenia; Nasci, Cristina

    2005-01-01

    The Venice Lagoon has been the focus of many environmental studies due to its heavy contaminant load derived from a variety of sources, including industrial activity, oil tanker traffic, and waste runoff from the mainland. In recent years, there has been increasing concern about water quality in the urban areas of Venice related to the discharge of untreated sewage directly into canals, adding to the pollutant load already existing in these areas. One way of gauging the impact of these chemicals is monitoring the local fauna. In the search for good indicators of water quality in the Venice urban area, two physiological indices for mussels-survival in air and condition index-have been evaluated. In 2002, a seasonal study was undertaken; mussels (Mytilus galloprovincialis) were collected in three sites located in the canals of the city and a clean reference site. At the same time, two transplantation experiments were performed, deploying farmed mussels for 1,2, 4, and 12 weeks in the historic centre of Venice and also at a reference site. Data from survival in air test and the condition index of native and transplanted mussels are reported. The results suggest an impact of the complex mixture of pollutants on mussel health status. Both native mussels and those transplanted to the urban area showed reduced survivability in air and decreased condition index values, indicating a less healthy status in animals from the canals of the city. Data are discussed in relation to pollutant bioaccumulation.

  12. Wind-induced Resuspension Events in the Venice Lagoon: evidence from the Past and Trends for the Future.

    NASA Astrophysics Data System (ADS)

    D'Alpaos, A.; Carniello, L.; D'Alpaos, L.; Rinaldo, A.

    2015-12-01

    Wind waves promote the erosion and degradation of ubiquitous geomorphic features of tidal landscapes, such as subtidal platforms, tidal flats and salt marshes. Both in the vertical and in the horizontal planes, wind-wave induced erosion is one of the chief processes controlling the morphodynamic evolution of shallow tidal basins. Wind-wave induced bottom shear stresses can promote the disruption of the polymeric microphytobenthic biofilm and lead to the erosion of tidal-flat surfaces and to the increase in suspended sediment concentration which in turn affects the stability of intertidal ecosystems. As an example, the Venice Lagoon has experienced strong erosion processes in the last two centuries, which progressively deepened the lagoonal bottoms, promoted the loss of fine cohesive sediments through the inlets after storms, and lead to the loss of extensive salt-marsh areas. Towards the goal of developing a synthetic theoretical framework to represent wind wave-induced resuspension events and account for their erosional effects on the long-term biomorphodynamic evolution of tidal systems, we employed a full-fledged finite element model accounting for the role of wind waves and tidal currents on the hydrodynamic circulation in shallow basins. Our analyses of the spatial and temporal characteristics of wind-induced erosion events for the actual configuration of the Venice Lagoon and for a few configurations of the last two centuries, allow us to reconstruct erosive trends typical of past Venice Lagoon configurations and to provide predictions on future scenarios for the Venice Lagoon.

  13. "I Could Teach You How to Choose Right": Using Holocaust Memoir to Teach Shakespeare's "The Merchant of Venice"

    ERIC Educational Resources Information Center

    Whaley, Annemarie Koning

    2011-01-01

    The article examines the problems of teaching William Shakespeare's "The Merchant of Venice" after the Holocaust, arguing that even though the play is anti-Semitic, it can become a valuable teaching tool when placed in the context of the Holocaust memoirs "Dry Tears" by Nechama Tec and "The Nazi Officer's Wife" by…

  14. Pupil Exchange in the European Community Venice Colloquium (October 24-28, 1977). Collection Studies. Education Series No. 5.

    ERIC Educational Resources Information Center

    Commission des Communautes Europeennes (Luxembourg).

    This publication contains the papers of the Venice Colloquium held in October, 1977 by educators from European countries to discuss the topic of visits and exchanges for pupils. There are seven chapters. Chapter one discusses the context and objectives of the colloquium. Chapter two describes pupil visits and exchanges in the European community.…

  15. Nonlinear-dynamical arrhythmia control in humans

    PubMed Central

    Christini, David J.; Stein, Kenneth M.; Markowitz, Steven M.; Mittal, Suneet; Slotwiner, David J.; Scheiner, Marc A.; Iwai, Sei; Lerman, Bruce B.

    2001-01-01

    Nonlinear-dynamical control techniques, also known as chaos control, have been used with great success to control a wide range of physical systems. Such techniques have been used to control the behavior of in vitro excitable biological tissue, suggesting their potential for clinical utility. However, the feasibility of using such techniques to control physiological processes has not been demonstrated in humans. Here we show that nonlinear-dynamical control can modulate human cardiac electrophysiological dynamics by rapidly stabilizing an unstable target rhythm. Specifically, in 52/54 control attempts in five patients, we successfully terminated pacing-induced period-2 atrioventricular-nodal conduction alternans by stabilizing the underlying unstable steady-state conduction. This proof-of-concept demonstration shows that nonlinear-dynamical control techniques are clinically feasible and provides a foundation for developing such techniques for more complex forms of clinical arrhythmia. PMID:11320216

  16. Nonlinear-dynamical arrhythmia control in humans.

    PubMed

    Christini, D J; Stein, K M; Markowitz, S M; Mittal, S; Slotwiner, D J; Scheiner, M A; Iwai, S; Lerman, B B

    2001-05-08

    Nonlinear-dynamical control techniques, also known as chaos control, have been used with great success to control a wide range of physical systems. Such techniques have been used to control the behavior of in vitro excitable biological tissue, suggesting their potential for clinical utility. However, the feasibility of using such techniques to control physiological processes has not been demonstrated in humans. Here we show that nonlinear-dynamical control can modulate human cardiac electrophysiological dynamics by rapidly stabilizing an unstable target rhythm. Specifically, in 52/54 control attempts in five patients, we successfully terminated pacing-induced period-2 atrioventricular-nodal conduction alternans by stabilizing the underlying unstable steady-state conduction. This proof-of-concept demonstration shows that nonlinear-dynamical control techniques are clinically feasible and provides a foundation for developing such techniques for more complex forms of clinical arrhythmia.

  17. Effectiveness of amiodarone in resistant arrhythmias1

    PubMed Central

    Hollman, Arthur; Holt, Phyllis M

    1980-01-01

    Amiodarone is used in the treatment of previously drug-resistant supraventricular and ventricular arrhythmias. We report our experience with amiodarone in 8 patients. Five patients had paroxysmal atrial flutter, one had paroxysmal atrial fibrillation, one had supraventricular tachycardia, and one ventricular tachycardia. Considerable improvement, both objectively and subjectively, was observed in all patients. Side effects were as follows: all patients had corneal microdeposits, one developed left bundle branch block which resolved on stopping amiodarone, and one reported constipation and abdominal pains. Six patients have been treated for 10–28 months; 3 developed tolerance at 4–14 months after the introduction of amiodarone therapy, but symptoms improved with increased dosage. It is important to watch for the development of tolerance to this drug. PMID:7452643

  18. The eSurge-Venice project: altimeter and scatterometer satellite data to improve the storm surge forecasting in the city of Venice

    NASA Astrophysics Data System (ADS)

    Zecchetto, Stefano; De Biasio, Francesco; Umgiesser, Georg; Bajo, Marco; Vignudelli, Stefano; Papa, Alvise; Donlon, Craig; Bellafiore, Debora

    2013-04-01

    On the framework of the Data User Element (DUE) program, the European Space Agency is funding a project to use altimeter Total Water Level Envelope (TWLE) and scatterometer wind data to improve the storm surge forecasting in the Adriatic Sea and in the city of Venice. The project will: a) Select a number of Storm Surge Events occurred in the Venice lagoon in the period 1999-present day b) Provide the available satellite Earth Observation (EO) data related to the Storm Surge Events, mainly satellite winds and altimeter data, as well as all the available in-situ data and model forecasts c) Provide a demonstration Near Real Time service of EO data products and services in support of operational and experimental forecasting and warning services d) Run a number of re-analysis cases, both for historical and contemporary storm surge events, to demonstrate the usefulness of EO data The re-analysis experiments, based on hindcasts performed by the finite element 2-D oceanographic model SHYFEM (https://sites.google.com/site/shyfem/), will 1. use different forcing wind fields (calibrated and not calibrated with satellite wind data) 2. use Storm Surge Model initial conditions determined from altimeter TWLE data. The experience gained working with scatterometer and Numerical Weather Prediction (NWP) winds in the Adriatic Sea tells us that the bias NWP-Scatt wind is negative and spatially and temporally not uniform. In particular, a well established point is that the bias is higher close to coasts then offshore. Therefore, NWP wind speed calibration will be carried out on each single grid point in the Adriatic Sea domain over the period of a Storm Surge Event, taking into account of existing published methods. Point #2 considers two different methodologies to be used in re-analysis tests. One is based on the use of the TWLE values from altimeter data in the Storm Surge Model (SSM), applying data assimilation methodologies and trying to optimize the initial conditions of the

  19. Role of the autonomic nervous system in modulating cardiac arrhythmias.

    PubMed

    Shen, Mark J; Zipes, Douglas P

    2014-03-14

    The autonomic nervous system plays an important role in the modulation of cardiac electrophysiology and arrhythmogenesis. Decades of research has contributed to a better understanding of the anatomy and physiology of cardiac autonomic nervous system and provided evidence supporting the relationship of autonomic tone to clinically significant arrhythmias. The mechanisms by which autonomic activation is arrhythmogenic or antiarrhythmic are complex and different for specific arrhythmias. In atrial fibrillation, simultaneous sympathetic and parasympathetic activations are the most common trigger. In contrast, in ventricular fibrillation in the setting of cardiac ischemia, sympathetic activation is proarrhythmic, whereas parasympathetic activation is antiarrhythmic. In inherited arrhythmia syndromes, sympathetic stimulation precipitates ventricular tachyarrhythmias and sudden cardiac death except in Brugada and J-wave syndromes where it can prevent them. The identification of specific autonomic triggers in different arrhythmias has brought the idea of modulating autonomic activities for both preventing and treating these arrhythmias. This has been achieved by either neural ablation or stimulation. Neural modulation as a treatment for arrhythmias has been well established in certain diseases, such as long QT syndrome. However, in most other arrhythmia diseases, it is still an emerging modality and under investigation. Recent preliminary trials have yielded encouraging results. Further larger-scale clinical studies are necessary before widespread application can be recommended.

  20. Effects of Heterogeneous Diffuse Fibrosis on Arrhythmia Dynamics and Mechanism

    NASA Astrophysics Data System (ADS)

    Kazbanov, Ivan V.; Ten Tusscher, Kirsten H. W. J.; Panfilov, Alexander V.

    2016-02-01

    Myocardial fibrosis is an important risk factor for cardiac arrhythmias. Previous experimental and numerical studies have shown that the texture and spatial distribution of fibrosis may play an important role in arrhythmia onset. Here, we investigate how spatial heterogeneity of fibrosis affects arrhythmia onset using numerical methods. We generate various tissue textures that differ by the mean amount of fibrosis, the degree of heterogeneity and the characteristic size of heterogeneity. We study the onset of arrhythmias using a burst pacing protocol. We confirm that spatial heterogeneity of fibrosis increases the probability of arrhythmia induction. This effect is more pronounced with the increase of both the spatial size and the degree of heterogeneity. The induced arrhythmias have a regular structure with the period being mostly determined by the maximal local fibrosis level. We perform ablations of the induced fibrillatory patterns to classify their type. We show that in fibrotic tissue fibrillation is usually of the mother rotor type but becomes of the multiple wavelet type with increase in tissue size. Overall, we conclude that the most important factor determining the formation and dynamics of arrhythmia in heterogeneous fibrotic tissue is the value of maximal local fibrosis.

  1. Increased Myofilament Ca2+-Sensitivity and Arrhythmia Susceptibility

    PubMed Central

    Huke, Sabine; Knollmann, Bjorn C.

    2010-01-01

    Increased myofilament Ca2+ sensitivity, a common attribute of inherited and acquired cardiomyopathies, is often associated with cardiac arrhythmias. Accumulating evidence supports that increased myofilament Ca2+ sensitivity is an independent risk factor for arrhythmias, but the underlying molecular mechanism remains unclear. This review focuses on potential mechanisms how myofilament Ca2+ sensitivity may affect cardiac excitation and leads to the generation of arrhythmias. We discuss in detail the downstream effects of increased myofilament Ca2+ sensitivity, i.e. altered Ca2+ buffering/handling, impaired energy metabolism and increased mechanical stretch, and how they may contribute to the proarrhythmic effect. PMID:20097204

  2. Cardiac arrhythmias during exercise testing in healthy men.

    NASA Technical Reports Server (NTRS)

    Beard, E. F.; Owen, C. A.

    1973-01-01

    Clinically healthy male executives who participate in a long-term physical conditioning program have demonstrated cardiac arrhythmia during and after periodic ergometric testing at submaximal and maximal levels. In 1,385 tests on 248 subjects, it was found that 34% of subjects demonstrated an arrhythmia at some time and 13% of subjects developed arrhythmia on more than one test. Premature systoles of ventricular origin were most common, but premature systoles of atrial origin, premature systoles of junctional origin, paroxysmal atrial tachycardia, atrioventricular block, wandering pacemaker, and pre-excitation were also seen. Careful post-test monitoring and pulse rate regulated training sessions are suggested for such programs.

  3. A troubled beginning: evolving concepts of an old arrhythmia.

    PubMed

    Hanon, Sam; Shapiro, Michael; Schweitzer, Paul

    2005-07-01

    The development of the sphygmograph in the nineteenth century marked the beginning of graphic registration of the arterial and venous pulse. Mackenzie, among other investigators, used this technique to study cardiac rhythm. In the early 20th century, Einthoven developed the electrocardiogram, which replaced the less sophisticated arterial and venous registrations of cardiac events and allowed for more detailed arrhythmia analysis. Interestingly, the early study of cardiac arrhythmias was obscured by misinterpretation. Specifically, atrial fibrillation stands out as a rhythm that was extensively studied though misconstrued in its early history. What follows is an in-depth consideration of the original investigations and evolving theories of this important arrhythmia.

  4. On the Lateral Retreat of Salt Marshes: Field Monitoring in the Venice Lagoon (Italy)

    NASA Astrophysics Data System (ADS)

    Solari, L.

    2015-12-01

    Salt marshes are geomorphic structures located in ecotone environments such as lagoon and estuaries, providing lot of ecosystem services to local population. In the last decades they are disappearing due to several factors such as sea level rise, subsidence and edge erosion due to surface waves. The latter is likely the chief mechanism modeling marsh boundaries and leading to the loss of wide marsh areas. In the case of the Venice Lagoon, from the beginning of the last century, the whole salt marsh surface has more than halved and trends indicate that the salt marshes might completely disappear over the next 50 years. Here, we present a field monitoring activity on a retreating salt marsh located in the north part of the Lagoon of Venice (Italy). The marsh is subject to North-East (Bora) wind. Marsh area loss during the last decades has been documented through the comparison of georeferenced aerial photographs showing a retreat rate of the order of 1 m/year. Field measurements started by the end of November 2013 and consist of: salt marsh bank geometry at different cross-sections and wave climate in the lagoon about 30 m in front of the salt marsh. Erosion data are obtained by means of erosion pins located horizontally on the marsh scarp; at higher banks (about 0.9 m), two pins are located along the same vertical direction, for lower banks (about 0.4 m), only one pin is employed. Significant wave height has been measured during three storm surges by means of pressure transducers. The measured wave climate in front of the bank was then put into relationship with the offshore wave climate estimated using wind data (intensity and direction) and bathymetric data. Wind intensity and direction is measured hourly by several measurement stations located in the Lagoon of Venice. In this way, it is possible to extrapolate wave climate hourly at the monitored marsh and calculate the wave power that acted on the bank in a given time interval. Field survey revealed that the

  5. Global change and relative sea level rise at Venice: what impact in term of flooding

    NASA Astrophysics Data System (ADS)

    Carbognin, Laura; Teatini, Pietro; Tomasin, Alberto; Tosi, Luigi

    2010-11-01

    Relative sea level rise (RSLR) due to climate change and geodynamics represents the main threat for the survival of Venice, emerging today only 90 cm above the Northern Adriatic mean sea level (msl). The 25 cm RSLR occurred over the 20th century, consisting of about 12 cm of land subsidence and 13 cm of sea level rise, has increased the flood frequency by more than seven times with severe damages to the urban heritage. Reasonable forecasts of the RSLR expected to the century end must be investigated to assess the suitability of the Mo.S.E. project planned for the city safeguarding, i.e., the closure of the lagoon inlets by mobile barriers. Here we consider three RSLR scenarios as resulting from the past sea level rise recorded in the Northern Adriatic Sea, the IPCC mid-range A1B scenario, and the expected land subsidence. Available sea level measurements show that more than 5 decades are required to compute a meaningful eustatic trend, due to pseudo-cyclic 7-8 year long fluctuations. The period from 1890 to 2007 is characterized by an average rate of 0.12 ± 0.01 cm/year. We demonstrate that linear regression is the most suitable model to represent the eustatic process over these 117 year. Concerning subsidence, at present Venice is sinking due to natural causes at 0.05 cm/year. The RSLR is expected to range between 17 and 53 cm by 2100, and its repercussions in terms of flooding frequency are associated here to each scenario. In particular, the frequency of tides higher than 110 cm, i.e., the value above which the gates would close the lagoon to the sea, will increase from the nowadays 4 times per year to a range between 20 and 250. These projections provide a large spread of possible conditions concerning the survival of Venice, from a moderate nuisance to an intolerable aggression. Hence, complementary solutions to Mo.S.E. may well be investigated.

  6. On the Lateral Retreat of Salt Marshes: Field Monitoring in the Venice Lagoon (Italy)

    NASA Astrophysics Data System (ADS)

    Solari, L.; Bendoni, M.; Mel, R.; Oumeraci, H.; Francalanci, S.; Lanzoni, S.

    2014-12-01

    Salt marshes are geomorphic structures located in ecotone environments such as lagoon and estuaries, providing lot of ecosystem services to local population. In the last decades they are disappearing due to several factors such as sea level rise, subsidence and edge erosion due to surface waves. The latter is likely the chief mechanism modeling marsh boundaries and leading to the loss of wide marsh areas. In the case of the Venice Lagoon, from the beginning of the last century, the whole salt marsh surface has more than halved and trends indicate that the salt marshes might completely disappear over the next 50 years. Here, we present a field monitoring activity that we are currently carrying out on a retreating salt marsh located in the north part of the Lagoon of Venice (Italy). The marsh is subject to North-East (Bora) wind. Marsh area loss during the last decades has been documented through the comparison of georeferenced aerial photographs showing a retreat rate of the order of 1 m/year. Field measurements started by the end of November 2013 and consist of: salt marsh bank geometry at different cross-sections and wave climate in the lagoon about 30 m in front of the salt marsh. Erosion data are obtained by means of erosion pins located horizontally on the marsh scarp; at higher banks (about 0.9 m), two pins are located along the same vertical direction, for lower banks (about 0.4m), only one pin is employed. Significant wave height has been measured during three storm surges by means of pressure transducers (Pts). The measured wave climate in front of the bank was then put into relationship with the offshore wave climate estimated using wind data (intensity and direction) and bathymetric data. Wind intensity and direction is measured hourly by several measurement stations located in the Lagoon of Venice. In this way, it is possible to extrapolate wave climate hourly at the monitored marsh and calculate the wave power that acted on the bank in a given time

  7. The Lido as Venice's refuse tip: Dalmatian sheep and the 1819 elephant.

    PubMed

    Giormani, Virgilio

    2004-01-01

    The Lido of Venice is an island twelve kilometers long and between a hundred and one thousand meters wide. The citizans of Venice and many turists can't imagine today, what Lido was some centuries ago Initially totally sandy, it was fertilized by means of a continuous supply of Venice's garbage (the "scoasse"). In addition to the "scoasse", damaged foodstuffs and the waste of the vegetable market were also sent to the Lido. Other fertilisers originated from the dung of the cattle and sheep arriving by ship from Dalmatia, which were landed on the Lido, where they could pasture before slaughter to regain weight lost during their voyage. The sheep dung, especially, was important for the proto-industrial production of saltpetre, a material of the greatest strategic importance, like uranium at the present time. Saltpetre is the most important component of gun powder, which was the only explosive known up to the second half of 19th century. There were plans to establish an "artificial nitriary" in the Lido, making use of the garbage and of the animal waste. In all probability, the most bulky item ever buried in the Lido is the corpse of an enraged elephant, which escaped from its cage on the Riva degli Schiavoni where it was performing during the 1819 carnival, and was killed by a cannon shot in a church where it took refuge. The original title of the paper, published in Italian is: V. Giormani, II Lido di Venezia "scoassera" della città. I montoni dalmati e l'elefante del 1819, in Atti del III Convegno nazionale di storia della medicina veterinaria, Lastra a Signa (Firenze), 23-24 settembre 2000, a cura di Alba Veggetti, Brescia, 2001, pp. 333-339. Other information has been added in order to facilitate non-italians readers and articles appearing after the publication of the Proceedings of the Third National Congress for the History of Veterinary Medicine, Lastra a Signa, (Florence), Italy, have also been used. I am deeply grateful to Mrs. Mary Moors for the

  8. Masterplan to safeguard Venice and to restore the lagoon and conterminous areas

    NASA Astrophysics Data System (ADS)

    Bini, Claudio; Gallo, Alba; Nadimi-Goki, Mandana; Wahsha, Mohammad

    2015-04-01

    Venice and its lagoon constitute a complex system, well known all over the world for the peculiarity of the town and for the fragility of the lagoon ecosystem with its delicate equilibrium. The whole system has been, and is currently, affected by human activities (industry, agriculture, settlements, tourism) that impact severely the ecosystem. Discharge from the agricultural drainage basin affects particularly the area North of the city of Venice; the central and southern areas, instead, receive important pollutant inputs from the industrial zone of Porto Marghera since the early'50s. Additional sources of pollution are domestic sewage and waste disposal from the urban area, that is visited by more than 10M people every year. As a consequence of the increasing land contamination, significant amounts of contaminants (both organic and inorganic) are accumulated in soils of the borderline, in water and in lagoon sediments, which constitute a potential source of secondary pollution. Results of surveys carried out in recent years in the whole area show that contaminants concentration increased from the beginning of the industrial activities until the '90s, when Porto Marghera declined. Most of contaminants have concentrations above the background levels. The highest metal levels were found in an area between Porto Marghera and the city of Venice, where both industrial and urban sewage are discharged, provoking environmental and human health hazard. In order to safeguard the city of Venice, and to restore its lagoon and conterminous areas, a Master Plan of intervention has been developed since the early 2000s. The land currently interested by environmental analysis and/or restoration covers approximately 1350ha; 78% of these (1100ha) proved variously contaminated, with 85% of sites overcoming the National Reference Values. Contamination, besides being diffused, is quite complex, involving the co-existence of several contaminant families (PAH, PCB, dioxin, heavy metals

  9. Mercury in the food chain of the Lagoon of Venice, Italy.

    PubMed

    Dominik, Janusz; Tagliapietra, Davide; Bravo, Andrea G; Sigovini, Marco; Spangenberg, Jorge E; Amouroux, David; Zonta, Roberto

    2014-11-15

    Sediments and biota samples were collected in a restricted area of the Lagoon of Venice and analysed for total mercury, monomethyl mercury (MMHg), and nitrogen and carbon isotopes. Results were used to examine mercury biomagnification in a complex food chain. Sedimentary organic matter (SOM) proved to be a major source of nutrients and mercury to primary consumers. Contrary to inorganic mercury, MMHg was strongly biomagnified along the food chain, although the lognormal relationship between MMHg and δ(15)N was less constrained than generally reported from lakes or coastal marine ecosystems. The relationship improved when logMMHg concentrations were plotted against trophic positions derived from baseline δ(15)N estimate for primary consumers. From the regression slope a mean MMHg trophic magnification factor of 10 was obtained. Filter-feeding benthic bivalves accumulated more MMHg than other primary consumers and were probably important in MMHg transfer from sediments to higher levels of the food chain.

  10. Polychlorinated biphenyl pollution caused by resuspension of surface sediments in the lagoon of Venice.

    PubMed

    Raccanelli, S; Pavoni, B; Marcomini, A; Orio, A A

    1989-03-01

    A mechanical device was used to reproduce in the laboratory the sediment resuspension caused by tidal currents and wind waves in the lagoon of Venice. Shear stresses comparable to those observed in the field were applied to the sediment surface. Series of experiments were run at 6.6 and 9.0 dyn/cm2. The concentration of polychlorinated biphenyls (PCBs) were determined in the sediments and resuspended particulate matter by means of gas chromatographic techniques. At the two different stresses, particulate matter with different grain size and different concentrations of PCBs was resuspended. However, no significant differences were observed in the amounts of PCBs mobilized per litre of water. In fact, by increasing the applied stress, coarser particulate matter was resuspended with a lower concentration of PCBs per unit of dry weight.

  11. Surface water-groundwater exchange in transitional coastal environments by airborne electromagnetics: The Venice Lagoon example

    NASA Astrophysics Data System (ADS)

    Viezzoli, A.; Tosi, L.; Teatini, P.; Silvestri, S.

    2010-01-01

    A comprehensive investigation of the mixing between salt/fresh surficial water and groundwater in transitional environments is an issue of paramount importance considering the ecological, cultural, and socio-economic relevance of coastal zones. Acquiring information, which can improve the process understanding, is often logistically challenging, and generally expensive and slow in these areas. Here we investigate the capability of airborne electromagnetics (AEM) at the margin of the Venice Lagoon, Italy. The quasi-3D interpretation of the AEM outcome by the spatially constrained inversion (SCI) methodology allows us to accurately distinguish several hydrogeological features down to a depth of about 200 m. For example, the extent of the saltwater intrusion in coastal aquifers and the transition between the upper salt saturated and the underlying fresher sediments below the lagoon bottom are detected. The research highlights the AEM capability to improve the hydrogeological characterization of subsurface processes in worldwide lagoons, wetlands, deltas.

  12. High Throughput, Multiplexed Pathogen Detection Authenticates Plague Waves in Medieval Venice, Italy

    PubMed Central

    Tran, Thi-Nguyen-Ny; Signoli, Michel; Fozzati, Luigi; Aboudharam, Gérard; Raoult, Didier; Drancourt, Michel

    2011-01-01

    Background Historical records suggest that multiple burial sites from the 14th–16th centuries in Venice, Italy, were used during the Black Death and subsequent plague epidemics. Methodology/Principal Findings High throughput, multiplexed real-time PCR detected DNA of seven highly transmissible pathogens in 173 dental pulp specimens collected from 46 graves. Bartonella quintana DNA was identified in five (2.9%) samples, including three from the 16th century and two from the 15th century, and Yersinia pestis DNA was detected in three (1.7%) samples, including two from the 14th century and one from the 16th century. Partial glpD gene sequencing indicated that the detected Y. pestis was the Orientalis biotype. Conclusions These data document for the first time successive plague epidemics in the medieval European city where quarantine was first instituted in the 14th century. PMID:21423736

  13. Harmful Algae Records in Venice Lagoon and in Po River Delta (Northern Adriatic Sea, Italy)

    PubMed Central

    Bilaničovà, Dagmar; Marcomini, Antonio

    2014-01-01

    A detailed review of harmful algal blooms (HAB) in northern Adriatic Sea lagoons (Po River Delta and Venice lagoon) is presented to provide “updated reference conditions” for future research and monitoring activities. In the study areas, the high mollusc production requires the necessity to identify better methods able to prevent risks for human health and socioeconomical interests. So, an integrated approach for the identification and quantification of algal toxins is presented by combining microscopy techniques with Liquid Chromatography coupled with High Resolution Time of Flight Mass Spectrometry (HPLC-HR-TOF-MS). The method efficiency was first tested on some samples from the mentioned coastal areas, where Dinophysis spp. occurred during summer in the sites directly affected by seawaters. Although cell abundance was always <200 cells/L, the presence of Pectenotoxin-2 (PTX2), detected by HPLC-HR-TOF-MS, indicated the potential release of detectable amounts of toxins even at low cell abundance. PMID:24683360

  14. Can Venice be raised by pumping water underground? A pilot project to help decide

    NASA Astrophysics Data System (ADS)

    Castelletto, N.; Ferronato, M.; Gambolati, G.; Putti, M.; Teatini, P.

    2008-01-01

    Recent field evidence suggests that injecting fluids below the ground surface can induce an anthropogenic land uplift of a few tens of centimeters over a time interval that may range from a few months to a few years. At the same time, new modeling studies using a lot of realistic hydrogeological and geomechanical information from the northern Adriatic basin indicate that pumping seawater into a 600-800 m deep brackish aquifer below the Venice Lagoon might help raise the city uniformly by 25-30 cm over 10 years (a). This could provide Venice with an important innovative defence from and a substantial mitigation to the so-called "acqua alta," i.e., the increasingly frequent floods that plague the city. To test the feasibility of an actual program of anthropogenic Venice uplift, a pilot project is designed with the aim of investigating the occurrence over a limited area selected on purpose within or in the margin of the lagoon where three boreholes down to 800 m are drilled and seawater properly treated for geochemical compatibility is pumped into the selected aquifer during 3 a. Using an improved reconstruction of the geology and lithostratigraphy from a new seismic survey to be carried out in the lagoon subsurface, the pilot project plans the instrumentation of the injection wells and other boreholes for the continuous monitoring and accurate measurement of (1) pore water overpressure; (2) expansion of the injected unit by the radioactive marker technique; (3) compaction, if any, of the upper fresh water aquifer system with the aid of an extensometer; and (4) vertical and horizontal motions of land surface via spirit leveling, GPS and interferometric synthetic aperture radar. Preliminary numerical simulations show that a constant saltwater injection rate of 12 × 103 m3 s-1 from each well might provide a maximum 7 cm uplift at the center of the selected site over a 3-a time, namely, a limited amount that is nevertheless accurately measurable and should not raise

  15. Did the Italian Government approve an obsolete project to save Venice?

    NASA Astrophysics Data System (ADS)

    Pirazzoli, Paolo Antonio

    The government of Silvio Berlusconi of Italy decided on 6 December 2001, to move forward with a project called the Experimental Electromechanical Module (MOSE) for mobile flood barriers at the inlets of the lagoon of Venice to protect the city from storm surges. This project is not only much debated for its environmental impacts, but it could also become rapidly obsolete in the event of a near-future sea-level rise.The Experimental Electromechanical Module project consists of 79 mobile gates at the three inlets to the lagoon. These will be closed when the tide height threatens to reach the level of 1.10 m above the mean sea level (MSL) of the period 1884-1909; that is, about 0.87 m above present MSL. The 20-m-long gates will lie on the floor of the lagoon inlets in normal times, but can be raised to partially seal the openings by injecting compressed air.

  16. Elderly woman with cerebrovascular accident and refractory arrhythmias.

    PubMed

    Sethi, S K; Sarm, P S A

    2009-11-01

    Fatal bilateral cerebro-vascular accident with variable atrio-ventricular blocks, atrial fibrillation and refractory tachy-arrhythmias in a previously healthy 75-years-old hypertensive female is presented.

  17. Atrial Arrhythmias in Astronauts. Summary of a NASA Summit

    NASA Technical Reports Server (NTRS)

    Barr, Yael; Watkins, Sharmila; Polk, J. D.

    2011-01-01

    This slide presentation reviews the findings of a panel of heart experts brought together to study if atrial arrhythmias more prevalent in astronauts, and potential risk factors that may predispose astronauts to atrial arrhythmias. The objective of the panel was to solicit expert opinion on screening, diagnosis, and treatment options, identify gaps in knowledge, and propose relevant research initiatives. While Atrial Arrhythmias occur in approximately the same percents in astronauts as in the general population, they seem to occur at younger ages in astronauts. Several reasons for this predisposition were given: gender, hypertension, endurance training, and triggering events. Potential Space Flight-Related Risk factors that may play a role in precipitating lone atrial fibrillation were reviewed. There appears to be no evidence that any variable of the space flight environment increases the likelihood of developing atrial arrhythmias during space flight.

  18. Therapy with conventional antiarrhythmic drugs for ventricular arrhythmias.

    PubMed

    Nestico, P F; DePace, N L; Morganroth, J

    1984-09-01

    Conventional antiarrhythmic drugs are an important tool for the clinical cardiologist for the treatment of ventricular arrhythmias. Knowledge of the different properties of these drugs will help decrease the incidence of adverse effects and increase the frequency of successful therapy.

  19. Recent advances in genetic testing and counseling for inherited arrhythmias.

    PubMed

    Mizusawa, Yuka

    2016-10-01

    Inherited arrhythmias, such as cardiomyopathies and cardiac ion channelopathies, along with coronary heart disease (CHD) are three most common disorders that predispose adults to sudden cardiac death. In the last three decades, causal genes in inherited arrhythmias have been successfully identified. At the same time, it has become evident that the genetic architectures are more complex than previously known. Recent advancements in DNA sequencing technology (next generation sequencing) have enabled us to study such complex genetic traits. This article discusses indications for genetic testing of patients with inherited arrhythmias. Further, it describes the benefits and challenges that we face in the era of next generation sequencing. Finally, it briefly discusses genetic counseling, in which a multidisciplinary approach is required due to the increased complexity of the genetic information related to inherited arrhythmias.

  20. Radiological impact of phosphogypsum discharged into the Venice lagoon: 222Rn

    NASA Astrophysics Data System (ADS)

    Cantaluppi, C.; Ceccotto, F.; Cianchi, A.; Fasson, A.; Degetto, S.

    2012-04-01

    For about 20 years, between the 60 's and the 80 's of the last century, in the Passo a Campalto area (Lagoon of Venice - Italy) about 400,000 m3 of phosphogypsum (PG) were deposited at the border of the lagoon and next to urban areas without any environmental control. These materials are a by-product formed during the wet processing of phosphate rocks by sulphuric acid and have a significant environmental impact due to their abundance and their chemical-physical and radiochemical characteristics. The PG contains both chemical elements, which are considered dangerous for the ecosystems and natural radionuclides whose concentrations are much higher if compared to those typical for the Earth's crust. These discarded materials caused for many years the dispersion of radionuclides in the environment due to the tidal erosion, the re-suspension of radioactive inhalable dusts, the uncontrolled radon exhalation and the bioaccumulation of some radionuclides in the lagoon environment. After a decision of the appointed authorities, the Venice Water Authority (Ministry of Infrastructure and Transport), planned a permanent safety control of the site resulting in the complete isolation of the entire volume of contaminated materials from the environmental system. The entire project was specific for the particular features of the site and it required the improvement of analytical, sampling and measurement techniques in order to verify the effectiveness of the safety action. The radon assessment, in particular the check of the effectiveness of the inhibition of radon exhalation, is part of a more complex study, covering many other aspects of the management of a permanent disposal; they will be the object of further notes. The ultimate results of this study prove the efficacy of the intervention: radon concentrations in air and exhalation values from the restored area, measured during surveys, have been proved to be well in agreement with those of non contaminated soils.

  1. Toxic metals in Venics lagoon sediments: Model, observation, an possible removal

    SciTech Connect

    Basu, A.; Molinaroli, E.

    1994-11-01

    We have modeled the distribution of nine toxic metals in the surface sediments from 163 stations in the Venice lagoon using published data. Three entrances from the Adriatic Sea control the circulation in the lagoon and divide it into three basins. We assume, for purposes of modeling, that Porto Marghera at the head of the Industrial Zone area is the single source of toxic metals in the Venice lagoon. In a standing body of lagoon water, concentration of pollutants at distance x from the source (C{sub 0}) may be given by C=C{sub 0}e{sup -kx} where k is the rate constant of dispersal. We calculated k empirically using concentrations at the source, and those farthest from it, that is the end points of the lagoon. Average k values (ppm/km) in the lagoon are: Zn 0.165, Cd 0.116, Hg 0.110, Cu 0.105, Co 0.072, Pb 0.058, Ni 0.008, Cr (0.011) and Fe (0.018 percent/km), and they have complex distributions. Given the k values, concentration at source (C{sub 0}), and the distance x of any point in the lagoon from the source, we have calculated the model concentrations of the nine metals at each sampling station. Tides, currents, floor morphology, additional sources, and continued dumping perturb model distributions causing anomalies (observed minus model concentrations). Positive anomalies are found near the source, where continued dumping perturbs initial boundary conditions, and in areas of sluggish circulation. Negative anomalies are found in areas with strong currents that may flush sediments out of the lagoon. We have thus identified areas in the lagoon where higher rate of sediment removal and exchange may lesson pollution. 41 refs., 4 figs., 3 tabs.

  2. Storm surge forecasting for operating the Venice Flood Barrier with minimal impact on port activities

    NASA Astrophysics Data System (ADS)

    Cecconi, Giovanni

    2015-04-01

    The operation of the Venice storm barrier, due to enter into operation by the end of 2017 , is particularly demanding in terms of the required accuracy of the forecast of the max water level for the time lead of 3-6 hours. With present sea level and safeguard level established at 1.1 m a.s.l. of 1895 the barrier is expected to be operated 10 times a year to cope with an average of 5 storms with around 15 redirections of the navigation through the locks. The 5 extra closures and the 10 extra interferences with navigation are needed for compensating the present forecast uncertainty of 10 cm in the maximum storm high for the required time lead of three hours, the time needed to stop navigation before the closures of the lagoon inlets. A decision support system based on these rules have been tested along the last four year with satisfactory results in term of reliability easy of operations. The forecast is presently based on a statistical model associated with a deterministic local model; the main source of uncertainty is related to the prediction of the local wind. Due to delays in the completion of Venice local protection till 1.1 m it is expected that the population will urge a reduction of the safeguard level from 1.1m to 0.9m with an exponential increase in the number of closures with greater impact on navigation. The present acceleration in sea level rise will also contribute to the increase in the number of closures. To reduce the impact on port activity, better forecast accuracy is required together with experimenting new operational closures : e.g. activating only the northern barriers. The paper evaluate the problem and the possible solutions in terms of improving storm surge forecast and developing new schemes for partial operation of the barriers for predicted limited floods not requiring complete closures.

  3. 5. 8 GHz ophthalmic microwave applicator for treatment of choroidal melanoma

    SciTech Connect

    Finger, P.T.; Packer, S.; Svitra, P.; Paglione, R.W.; Albert, D.M.; Chess, J.

    1983-01-01

    We report on the use of a 5.8 GHz microwave applicator to treat choroidal melanoma (Greene) in rabbits. The physical requirements needed to treat these intraocular tumors are quite different from those encountered elsewhere in the body. From a trans-scleral approach the penetration needed is minimal (5 to 10 mm.). The fibrous sclera is the only structure between the heat source and the tumor. The sclera has a relatively low water content when compared to tumor. This fact in addition to the frequency dependent interactions of tissue and electromagnetic radiation, results in an advantage to the use of the 5.8 GHz microwave device in treating intraocular malignancies.

  4. [Ryanodine receptor, calcium leak and arrhythmias].

    PubMed

    Rueda, Angélica; de Alba-Aguayo, David R; Valdivia, Héctor H

    2014-01-01

    The participation of the ionic Ca(2+) release channel/ryanodine receptor in cardiac excitation-contraction coupling is well known since the late '80s, when various seminal papers communicated its purification for the first time and its identity with the "foot" structures located at the terminal cisternae of the sarcoplasmic reticulum. In addition to its main role as the Ca(2+) channel responsible for the transient Ca(2+) increase that activates the contractile machinery of the cardiomyocytes, the ryanodine receptor releases Ca(2+) during the relaxation phase of the cardiac cycle, giving rise to a diastolic Ca(2+) leak. In normal physiological conditions, diastolic Ca(2+) leak regulates the proper level of luminal Ca(2+), but in pathological conditions it participates in the generation of both, acquired and hereditary arrhythmias. Very recently, several groups have focused their efforts into the development of pharmacological tools to control the altered diastolic Ca(2+) leak via ryanodine receptors. In this review, we focus our interest on describing the participation of cardiac ryanodine receptor in the diastolic Ca(2+) leak under physiological or pathological conditions and also on the therapeutic approaches to control its undesired exacerbated activity during diastole.

  5. Ethanol for the treatment of cardiac arrhythmias

    PubMed Central

    Schurmann, Paul; Peñalver, Jorge; Valderrábano, Miguel

    2015-01-01

    Introduction Ethanol infusion was an early mode of ablative treatment for cardiac arrhythmias. Its initial descriptions involved coronary intra-arterial delivery, targeting arrhythmogenic substrates in drug-refractory ventricular tachycardia or the atrioventricular node. Largely superseded by radiofrequency ablation (RFA) and other contact-based technologies as a routine ablation strategy, intracoronary arterial ethanol infusion remains as an alternative option in the treatment of ventricular tachycardia when conventional ablation fails. Arrhythmic foci that are deep-seated in the myocardium may not be amenable to catheter ablation from either the endocardium or the epicardium by RFA, but they can be targeted by an ethanol infusion. Recent findings Recently, we have explored ethanol injection through cardiac venous systems, in order to avoid the risks of complications and limitations of coronary arterial instrumentation. Vein of Marshall ethanol infusion is being studied as an adjunctive procedure in ablation of atrial fibrillation, and coronary venous ethanol infusion for ventricular tachycardia. Conclusion Ethanol ablation remains useful as a bail-out technique for refractory cases to RFA, or as an adjunctive therapy that may improve the efficacy of catheter ablation procedures. PMID:26049378

  6. Update on management of cardiac arrhythmias in acute coronary syndromes.

    PubMed

    Willich, T; Goette, A

    2015-04-01

    This review summarizes different types of arrhythmias in patients with acute coronary syndromes and provides an overview of the available therapeutic options for acute care and management of critical arrhythmias. The different therapeutic options are depending on the origin and type of arrhythmia. The main common dominant mechanisms are intramural re-entry in ischemia and triggered activity in reperfusion. The different forms of arrhythmia were explained in detail. Atrial arrhythmias are mainly atrial fibrillation; other forms are rare and usually self-limited. As therapeutic options antiarrhythmic drug therapy with beta-blockers or amiodarone and direct current cardioversion are suitable. Ventricular arrhythmias can be divided in premature ventricular complexes, accelerated idioventricular rhythm, non-sustained ventricular tachycardia, sustained ventricular tachycardia (VT), ventricular fibrillation (VF) and electrical storm. As therapeutic options antiarrhythmic drug therapy, implantable cardioverter defibrillator therapy (ICD), radiofrequency catheter ablation (RFA) and stellate ganglion blockade are available. The treatment with antiarrhythmic drug is rather cautious recommended, with the exception of beta-blockers. An additional drug therapy with ranolazine may be considered. The advantage of ICD therapy for long-term primary or secondary prophylactic therapy has been well documented. ICD therapy is associated with significant reduction in mortality compared with antiarrhythmic drug therapy (mainly amiodarone), with the exception of beta-blockers. RFA and stellate ganglion blockade are rather intended as therapeutically options for incessant VT/VF or electrical storm.

  7. Development and validation of a new Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia (ASTA) with focus on symptom burden

    PubMed Central

    2012-01-01

    Background Arrhythmias can appear with a variety of symptoms, all from vague to pronounced and handicapping symptoms. Therefore, patient-reported outcomes (PROs) concerning symptom burden are important to assess and take into consideration in the care and treatment of patients with arrhythmias. The main purpose was to develop and validate a disease-specific questionnaire evaluating symptom burden in patients with different forms of arrhythmias. Methods A literature review was conducted and arrhythmia patients were interviewed. Identified symptoms were evaluated by an expert panel consisting of cardiologists and nurses working daily with arrhythmia patients. SF-36 and Symptoms Checklist (SCL) were used in the validation of the new questionnaire Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia (ASTA). Homogeneity was evaluated with Spearman´s correlations and Cronbach´s alpha coefficient (α) was used to evaluate internal consistency. Construct validity was evaluated using item-total correlations and convergent and discriminant validity. For this, Spearman´s correlations were calculated between the ASTA symptom scale, SCL and SF-36. Concurrent validity was validated by Spearman´s correlations between the ASTA symptom scale and SCL. Results The correlations between the different items in the ASTA symptom scale showed generally sufficient homogeneity. Cronbach´s coefficient was found to be satisfactory (α = 0.80; lower bound 95 % CI for α = 0.76). Construct validity was supported by item-total correlations where all items in the symptom scale were sufficiently correlated (≥0.3). Convergent and discriminant validity was supported by the higher correlations to the arrhythmia-specific SCL compared to the generic SF-36. Concurrent validity was evaluated and there were sufficiently, but not extremely strong correlations found between the ASTA symptom scale and SCL. Conclusions The nine items of the ASTA symptom scale were found to have good

  8. Into Adolescence: Enhancing Self-Esteem. A Curriculum for Grades 5-8. Contemporary Health Series.

    ERIC Educational Resources Information Center

    Zevin, Dale; McPherson, Carole

    This book is a 10-lesson module for grades 5-8, designed to increase students' awareness of self-esteem as a dynamic, ever-changing component in their lives. Beginning with a "Full Esteem Ahead" lesson to help students identify high and low self-esteem behaviors, this module gives teachers specific instructional strategies for guiding students…

  9. Earth Science Supplement to the Syllabus, Part 2, Topics 5-8, 1970 Edition. 1974 Reprint.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    This document contains investigation topics 5-8 in the earth science course developed by the University of the State of New York for secondary schools. Topics include energy in earth processes, insulation and the earth's surface, energy exchanges in the atmosphere, moisture and energy budgets, and environmental change. Each topic is preceded by…

  10. Through My Eyes: A Child's View of World War II. Appropriate for Grades 5-8.

    ERIC Educational Resources Information Center

    Brooks, Margaret

    This activity book is designed for grades 5-8 to look at America at home during World War II. The work examines the efforts of the men, women, and children who supported and supplied one of the greatest mobilizations of people and material that the world has ever witnessed. The activities were planned to compliment the exhibit of the same name,…

  11. The Columbia River: Its Future and You. Teacher's Manual for Grades 5-8.

    ERIC Educational Resources Information Center

    Frost, Marcia

    Designed as a part of a multidisciplinary set of curricula and educational materials on the Columbia River, this teacher's guide focuses on the many uses of the river and the conflicts arising from those uses. This unit's major purpose is to help students in grades 5-8 to start thinking about how the resources of the Columbia River should be…

  12. C.T.B.S. Testing. Spring 1982 District Report, 5, 8, and 11.

    ERIC Educational Resources Information Center

    O'Neal, Sandra

    Each spring the Comprehensive Tests of Basic Skills (CTBS) are administered to grades 5, 8, and 11 throughout New Mexico as part of the State Department of Education mandated assessment program. This report contains information regarding Albuquerque Public Schools' results on the 1982 CTBS. A new form of the CTBS was selected for testing fifth and…

  13. Molecular Systematics of Dictyostelids: 5.8S Ribosomal DNA and Internal Transcribed Spacer Region Analyses▿

    PubMed Central

    Romeralo, María; Escalante, Ricardo; Sastre, Leandro; Lado, Carlos

    2007-01-01

    The variability and adaptability of the amoebae from the class Dictyosteliomycetes greatly complicate their systematics. The nucleotide sequences of the ribosomal internal transcribed spacers and the 5.8S ribosomal DNA gene have been determined for 28 isolates, and their utility to discriminate between different species and genera has been shown. PMID:17056743

  14. Exploring with Computers in Vikingland. AEDS-81 Convention Proceedings (Minneapolis, Minnesota, May 5-8, 1981).

    ERIC Educational Resources Information Center

    Association for Educational Data Systems, Washington, DC.

    This publication presents a summary of and index to the presentations given at the Association for Educational Data Systems (AEDS) Convention held in Minneapolis, Minnesota, during May 5-8, 1981. Summarized are 66 short papers that cover a variety of educational computing activities and projects completed by educational institutions,…

  15. Cardiac arrhythmias induced by chloral hydrate in rhesus monkeys.

    PubMed

    Han, Pengfei; Song, Haibo; Yang, Pingliang; Xie, Huiqi; Kang, Y James

    2011-06-01

    Chloral hydrate has been long used as a safe sedative and hypnotic drug in humans. However, reports on its cardiovascular adverse effects have been published from time to time. The present study was undertaken to use Rhesus monkeys as a model to define the dose regiment of chloral hydrate at which cardiac arrhythmias can be induced and the consequences of the cardiac events. Male Rhesus monkeys of 2-3 years old were intravenously infused with chloral hydrate starting at 50 mg/kg with an increasing increment of 25 mg/kg until the occurrence of cardiac arrhythmias. In addition, a traditional up-and-down dosing procedure was applied to define a single dose level at which cardiac arrhythmias can be induced. The data obtained showed that when the sequentially escaladed dose reached 125 mg/kg, cardiac arrhythmias occurred in all monkeys tested. The single effective dose to cause cardiac arrhythmias calculated from the crossover analysis was 143 ± 4 mg/kg. This value would be equivalent to 68.6 ± 1.9 mg/kg for children and 46.4 ± 1.3 mg/kg for adults in humans. Under either multiple or single dose condition, cardiac arrhythmias did not occur before 40 min after the onset of anesthesia induced by chloral hydrate. Cardiac arrhythmias were recovered without help at the end of the anesthesia in most cases, but also continued after the regain of consciousness in some cases. The cardiac arrhythmias were accompanied with compromised cardiac function including suppressed fractional shortening and ejection fraction. This study thus suggests that cautions need to be taken when chloral hydrate is used above certain levels and beyond a certain period of anesthesia, and cardiac arrhythmias induced by chloral hydrate need to be closely monitored because compromised cardiac function may occur simultaneously. In addition, patients with cardiac arrhythmias induced by chloral hydrate should be monitored even after they are recovered from the anesthesia.

  16. Thermal pollution and settlement of new tropical alien species: The case of Grateloupia yinggehaiensis (Rhodophyta) in the Venice Lagoon

    NASA Astrophysics Data System (ADS)

    Wolf, M. A.; Sfriso, A.; Moro, I.

    2014-06-01

    The Venice Lagoon has become increasingly affected by the introduction of allochthonous macroalgae mainly coming from the Indo-Pacific area. In consequence to the recent climate changes and temperature increase, such species could simply find numerous habitats suitable for their growth. One local process that contributes to water temperature changes is thermal pollution. In this study we used the DNA barcoding method to identify a new alien macroalgal species, Grateloupia yinggehaiensis Wang et Luan (Rhodophyta), found near the industrial area of Porto Marghera (Venice, Italy) hosting the Fusina thermoelectric power plant. The microclimate of this area has enabled the spread of this species native of the tropical area of the Hainan Province (China) and probably introduced in the Mediterranean Sea via shellfish transfers.

  17. Sedimentological, archeological and historical evidences of paleoclimatic changes during the holocene in the lagoon of Venice (Italy)

    SciTech Connect

    Bonardi, M.; Canal, E.; Cavazzoni, S.

    1997-12-31

    Sedimentological investigations and archeological and historical information have allowed to correlate paleoenvironmental and coastline variations, in the Lagoon of Venice, to climatic changes during the Holocene. In particular, we report the results of a detailed study of Holocene sediments, from salt marshes and small islands, taken above and below a level with well dated archeological findings that gave a good indication of the mean sea level.

  18. Cultural Resource Investigations within the U.S. Army Corps of Engineers New Orleans to Venice Hurricane Protection Project

    DTIC Science & Technology

    1988-12-01

    base of operations until after the Battle at Chalmette. In December 1814 , the British land forces made their way to St. Bernard Parish and advanced...City Price to Tropical Bend ......... ............ 102 Reach B-1: Tropical Bend to Fort Jackson and Reach B-2: Fort Jackson to Venice...NOV Area boundaries and the locations of the reaches and levees. 3 Price to Tropical Bend , Louisiana (River miles 30.4 to 44.9)" (Davis et al. 1978:2

  19. A 5.8S nuclear ribosomal RNA gene sequence database: applications to ecology and evolution

    NASA Technical Reports Server (NTRS)

    Cullings, K. W.; Vogler, D. R.

    1998-01-01

    We complied a 5.8S nuclear ribosomal gene sequence database for animals, plants, and fungi using both newly generated and GenBank sequences. We demonstrate the utility of this database as an internal check to determine whether the target organism and not a contaminant has been sequenced, as a diagnostic tool for ecologists and evolutionary biologists to determine the placement of asexual fungi within larger taxonomic groups, and as a tool to help identify fungi that form ectomycorrhizae.

  20. The effect of gamma irradiation on the fluorescence properties of 1,4,5,8-naphtalisoimides

    NASA Astrophysics Data System (ADS)

    Mazurak, Zbigniew; Wanic, Andrzej; Domański, Marian; Jarząbek, Bożena; Kaczmarczyk, Bożena; Konefał, Adam; Kądziołka-Gaweł, Mariola; Czaja, Maria

    2015-05-01

    The subject of our investigation was the intensity of the fluorescence of 1,4,5,8-naphtalisoimides subjected to gamma radiation (the absorbed doses were 242 Gy, 1 kGy and 2.242 kGy). Dynamic changes of fluorescence intensity have been observed; the greatest relative increase of fluorescence intensity (and simultaneously, the least durable increase) occurs as a result of structural isomerisation.

  1. Clinical outcome and circulatory effects of fetal cardiac arrhythmia.

    PubMed

    Lingman, G; Lundström, N R; Marsál, K

    1986-01-01

    By means of abdominal fetal ECG and non-invasive ultrasound blood flow studies 113 cases of fetal cardiac arrhythmia were classified according to the origin of arrhythmia. Pregnancy outcome was characterized by an increased frequency of fetal distress and heart malformation, and increased fetal and neonatal mortality. The following types of arrhythmia were identified: supraventricular extrasystoles (n = 84), paroxysmal tachycardia (n = 6), sinus bradycardia (n = 3), atrial flutter (n = 1), ventricular extrasystoles (n = 14), and atrioventricular block (n = 5). In 37 cases the combined Doppler and real-time ultrasound technique was used to measure fetal aortic blood flow as a means of studying the circulatory effects of the arrhythmia. Increased peak velocity, rising slope and acceleration were found in the first post-pausal beat after a supraventricular extrasystole or a missed beat; this supports the validity of Frank-Starling law for the fetal heart and suggests that a strong relationship exists between these variables and myocardial contractility. In two cases of intra-uterine heart failure, the effect of digoxin treatment in utero on the fetal aortic flow variables was studied, results indicating a positive inotropic effect of the drug on the fetal myocardium. The estimation of fetal aortic volume blood flow in cases of fetal cardiac arrhythmia is useful for early detection of fetal cardiac failure, and for monitoring the effects of intra-uterine treatment.

  2. Macrolide Antibiotics and the Risk of Cardiac Arrhythmias

    PubMed Central

    Schuller, Joseph L.

    2014-01-01

    Randomized, controlled trials have demonstrated that chronic therapy with macrolide antibiotics reduces the morbidity of patients with cystic fibrosis, non–cystic fibrosis bronchiectasis, chronic obstructive pulmonary disease, and nontuberculous mycobacterial infections. Lower levels of evidence indicate that chronic macrolides are also effective in treating patients with panbronchiolitis, bronchiolitis obliterans, and rejection after lung transplant. Macrolides are known to cause torsade des pointes and other ventricular arrhythmias, and a recent observational study prompted the FDA to strengthen the Warnings and Precautions section of azithromycin drug labels. This summary describes the electrophysiological effects of macrolides, reviews literature indicating that the large majority of subjects experiencing cardiac arrhythmias from macrolides have coexisting risk factors and that the incidence of arrhythmias in absence of coexisting risk factors is very low, examines recently published studies describing the relative risk of arrhythmias from macrolides, and concludes that this risk has been overestimated and suggests an approach to patient evaluation that should reduce the relative risk and the incidence of arrhythmias to the point that chronic macrolides can be used safely in the majority of subjects for whom they are recommended. PMID:24707986

  3. Cardiac arrhythmias in hypokalemic periodic paralysis: Hypokalemia as only cause?

    PubMed

    Stunnenberg, Bas C; Deinum, Jaap; Links, Thera P; Wilde, Arthur A; Franssen, Hessel; Drost, Gea

    2014-09-01

    It is unknown how often cardiac arrhythmias occur in hypokalemic periodic paralysis (HypoPP) and if they are caused by hypokalemia alone or other factors. This systematic review shows that cardiac arrhythmias were reported in 27 HypoPP patients. Cases were confirmed genetically (13 with an R528H mutation in CACNA1S, 1 an R669H mutation in SCN4A) or had a convincing clinical diagnosis of HypoPP (13 genetically undetermined) if reported prior to the availability of genetic testing. Arrhythmias occurred during severe hypokalemia (11 patients), between attacks at normokalemia (4 patients), were treatment-dependent (2 patients), or unspecified (10 patients). Nine patients died from arrhythmia. Convincing evidence for a pro-arrhythmogenic factor other than hypokalemia is still lacking. The role of cardiac expression of defective skeletal muscle channels in the heart of HypoPP patients remains unclear. Clinicians should be aware of and prevent treatment-induced cardiac arrhythmia in HypoPP.

  4. Macrolide antibiotics and the risk of cardiac arrhythmias.

    PubMed

    Albert, Richard K; Schuller, Joseph L

    2014-05-15

    Randomized, controlled trials have demonstrated that chronic therapy with macrolide antibiotics reduces the morbidity of patients with cystic fibrosis, non-cystic fibrosis bronchiectasis, chronic obstructive pulmonary disease, and nontuberculous mycobacterial infections. Lower levels of evidence indicate that chronic macrolides are also effective in treating patients with panbronchiolitis, bronchiolitis obliterans, and rejection after lung transplant. Macrolides are known to cause torsade des pointes and other ventricular arrhythmias, and a recent observational study prompted the FDA to strengthen the Warnings and Precautions section of azithromycin drug labels. This summary describes the electrophysiological effects of macrolides, reviews literature indicating that the large majority of subjects experiencing cardiac arrhythmias from macrolides have coexisting risk factors and that the incidence of arrhythmias in absence of coexisting risk factors is very low, examines recently published studies describing the relative risk of arrhythmias from macrolides, and concludes that this risk has been overestimated and suggests an approach to patient evaluation that should reduce the relative risk and the incidence of arrhythmias to the point that chronic macrolides can be used safely in the majority of subjects for whom they are recommended.

  5. Natural versus anthropogenic subsidence of Venice: investigation of the present occurrence by PSI

    NASA Astrophysics Data System (ADS)

    Tosi, Luigi; Strozzi, Tazio; Teatini, Pietro

    2014-05-01

    We detected land displacements of Venice by Persistent Scatterer Interferometry (PSI) using ERS and ENVISAT C-band and TerraSAR-X and COSMO-SkyMed X-band acquisitions over the periods 1992-2010 and 2008-2011, respectively. PSI provides the cumulative land displacements (natural plus anthropogenic) of the investigated area independently of the radar band. The natural subsidence rate depends on the reference period and, due to the present elevation of Venice with respect to the sea level, it is much more interesting for the city to evaluate the natural displacement over the last few decades, i.e. the present natural land subsidence, than that averaged over geological periods. Concerning anthropogenic land subsidence the contribution due to activities characterized by large scale and long term effects, e.g., that caused by groundwater withdrawals, ended a few decades ago. Today, the anthropogenic component of the land subsidence is only due to local, short-time interventions such as restoration works and inherent deformations of historical structures. By reason of the larger observation period, the C-band sensors were used to quantify the long-term movements, i.e. the subsidence component primarily ascribed to natural processes. The high resolution, short revisiting time X-band satellites reveal a high effectiveness to monitor short-time movements as those induced by human activities. The statistical analysis of the displacement distributions measured by PSI points out that the average rates, i.e. the natural component of the subsidence, are almost equal with the C-band and X-band satellites. Conversely, the standard deviation with X-band acquisitions (1.6 mm/yr) is characterized by a value significantly larger than that detected with C-band images (0.7 mm/yr). The larger X-band variability superposes to a background velocity similar to that given by ERS/ENVISAT. It is reasonable to assume that the difference between the movements provided by ERS/ENVISAT and Terra

  6. Remediation of heavy metal contaminated sites in the Venice lagoon and conterminous areas (Northern Italy)

    NASA Astrophysics Data System (ADS)

    Bini, Claudio; Wahsha, Mohammad; Fontana, Silvia; Maleci, Laura

    2013-04-01

    The lagoon of Venice and the conterminous land are affected by heavy contamination of anthropogenic origin, and for this reason the whole area has been classified as site of national interest, and must be restored. Heavy metals (As, Cd, Cr, Cu, Hg, Mn, Pb, Sb, Se, Zn) and organic compounds (IPA, PCB, Dioxine) have been identified as the main contaminants at various sites, owing to agriculture and industrial wastes discharged on soils and convoyed to the lagoon. Five case studies of soil remediation are here reported. S. Giuliano is a former palustrine area reclaimed since the 60's with various human transported materials (HTM). In this area, hot spots overpassing the reference limits for residential and green areas have been recorded for Cd, Cu, Pb, Zn and IPA. Campalto is a site bordering the Venice lagoon and subjected to oscillating water level, that enhances metal mobility; diffuse contamination by heavy metals, particularly Pb, has been recorded at this site, utilized since 30 years for military and sport (skate) activities. Marghera is dramatically famous for its numerous factories and for oil refineries that affected the lagoon sediments since the 50's. Sediments proved heavily contaminated by As (up to 137 mgkg-1), Cd (57 mgkg-1), Hg (30mgkg-1), Ni, Pb (700 mgkg-1), Zn (5818 mgkg-1). Murano is a small island where many glass factories (the most famous all over the world) are running since XIII century. Glass is stained with several metals and, moreover, some substances are used to regulate fusion temperature, purity, etc., and therefore the surrounding environment is heavily contaminated by these substances. Mean concentrations of As (429 mgkg-1), Cd (1452 mgkg-1), Pb (749 mgkg-1), Zn (1624 mgkg-1), Se (341 mgkg-1), Sb (74 mgkg-1) widely overpass the reference values for both residential and industrial areas in national guidelines. Molo Serbatoi is a former oil container currently under restoration in the port of Venice. Soil contamination by As, Hg, Zn and

  7. BMP-Smad 1/5/8 signalling in the development of the nervous system.

    PubMed

    Hegarty, Shane V; O'Keeffe, Gerard W; Sullivan, Aideen M

    2013-10-01

    The transcription factors, Smad1, Smad5 and Smad8, are the pivotal intracellular effectors of the bone morphogenetic protein (BMP) family of proteins. BMPs and their receptors are expressed in the nervous system (NS) throughout its development. This review focuses on the actions of Smad 1/5/8 in the developing NS. The mechanisms by which these Smad proteins regulate the induction of the neuroectoderm, the central nervous system (CNS) primordium, and finally the neural crest, which gives rise to the peripheral nervous system (PNS), are reviewed herein. We describe how, following neural tube closure, the most dorsal aspect of the tube becomes a signalling centre for BMPs, which directs the pattern of the development of the dorsal spinal cord (SC), through the action of Smad1, Smad5 and Smad8. The direct effects of Smad 1/5/8 signalling on the development of neuronal and non-neuronal cells from various neural progenitor cell populations are then described. Finally, this review discusses the neurodevelopmental abnormalities associated with the knockdown of Smad 1/5/8.

  8. Risk of land degradation due to saltwater intrusion along the Venice coastland, Italy

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Manoli, G.; Scudiero, E.; Deiana, R.; Perri, M.; Braga, F.; Tosi, L.; Putti, M.; Morari, F.

    2012-12-01

    The southern portion of the Venice coastland includes a very precarious environment. Due to an elevation down to 4 m below msl, the Venice Lagoon and Adriatic Sea proximity, and the encroachment of seawater from the mouth of the river network up to 20 km inland, salt contamination of land and groundwater is a severe problem that is seriously impacting the farmland productivity. An interdisciplinary multi-scale research is ongoing with the aim of understanding the contamination process, quantifying the effect of the saltwater intrusion of the crop production, and proposing possible mitigation strategies. A 25 ha basin cultivated with maize crop and representative of the area has been deeply monitored at various scales ranging from a few square meter plots up to the whole basin. Geophysical surveys, lab testing on soil and water samples, continuous measurements of hydrological parameters, physiological crop parameters, proximal sensing and multi-spectral remote sensing acquisitions, together with precise crop yield distribution were performed and acquired from 2010 to 2012. Geomorphological investigations, seismic and geo-electrical surveys combined with salt concentration measurements in the surficial waterbodies and groundwater (down to 10 m deep) are used to delineate the major pathways of seawater intrusion. Relationships existing between soil, water, crop factors and crop yield were identified, helping to assess plant stress at both the canopy and landscape level. The dataset is now used to set-up a three-dimensional numerical model of saturated/unsaturated water dynamics coupled with a crop-growth model. The model is applied at the basin scale to investigate the effects of water stress and soil contamination on the crop production. Once calibrated on hydrological records (e.g., groundwater levels, capillary pressure, etc.), crop growth, and yield production, the model will be applied to investigate expected scenarios related with the change of natural

  9. Saltwater contamination in the Venice Lagoon margin. Effects on soil productivity

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Scudiero, E.; Braga, F.; Piragnolo, D.; Deiana, R.; Manoli, G.; Berti, A.; Morari, F.

    2011-12-01

    The Venice watershed includes a very precarious coastal environment subject to both natural and anthropogenic changes with a significant and economically important fraction of the coastal farmland presently below mean sea level. In the hydrogeological context of the Venice coastland, a large risk of saltwater contamination characterizes the southernmost area because of the geomorphological setting of the coastal plain. Salt contamination is influenced also by the activity of several pumping stations used to keep drained the area, groundwater withdrawals, irrigation and freshwater releases during summer dry months. The impact of salt intrusion from the salty water bodies on soil productivity has been studied in the years 2010-2011. In a 25 ha basin cultivated with maize crop, soil salinity (electrical conductivity 1:2) and the main physical-chemical properties of the soil (e.g. texture, pH, organic carbon and CSC) were measured along the 1.5 m soil profile in 120 positions. Maps of apparent electrical conductivity (ECa) at three different investigation depths (0 - 0.75 m; 0-1.50 m; 0- 6.00 m) were also obtained in April 2010 and April 2011 with a CMD electromagnetic conductivity meter (GF Instruments) associated to a DGPS. During the 2-year period some physiological crop parameters, in particular leaf reflectance (i.e. Spectrascan, Photoresearch) and leaf ions content were monitored across the study area. Moreover, maps of NDVI were obtained by proximal sensing (three dates each year) using an active spectral radiometer (Crop Circle, Holland Scientific) and remote sensing acquiring WorldView-2 satellite images at the end of July 2010 and beginning of July 2011. Finally, maps of the crop yield were obtained at the end of the growing seasons by a yield mapping system mounted on a combine harvester. Relationships existing between soil, crop factors and crop yield were identified applying a multivariate spatial model, helping to assess plant stress at both the canopy

  10. Electrocardiographic abnormalities and cardiac arrhythmias in chronic obstructive pulmonary disease.

    PubMed

    Goudis, Christos A; Konstantinidis, Athanasios K; Ntalas, Ioannis V; Korantzopoulos, Panagiotis

    2015-11-15

    Chronic obstructive pulmonary disease (COPD) is independently associated with an increased burden of cardiovascular disease. Besides coronary artery disease (CAD) and congestive heart failure (CHF), specific electrocardiographic (ECG) abnormalities and cardiac arrhythmias seem to have a significant impact on cardiovascular prognosis of COPD patients. Disturbances of heart rhythm include premature atrial contractions (PACs), premature ventricular contractions (PVCs), atrial fibrillation (AF), atrial flutter (AFL), multifocal atrial tachycardia (MAT), and ventricular tachycardia (VT). Of note, the identification of ECG abnormalities and the evaluation of the arrhythmic risk may have significant implications in the management and outcome of patients with COPD. This article provides a concise overview of the available data regarding ECG abnormalities and arrhythmias in these patients, including an elaborated description of the underlying arrhythmogenic mechanisms. The clinical impact and prognostic significance of ECG abnormalities and arrhythmias in COPD as well as the appropriate antiarrhythmic therapy and interventions in this setting are also discussed.

  11. Role of adipose tissue in the pathogenesis of cardiac arrhythmias.

    PubMed

    Samanta, Rahul; Pouliopoulos, Jim; Thiagalingam, Aravinda; Kovoor, Pramesh

    2016-01-01

    Epicardial adipose tissue is present in normal healthy individuals. It is a unique fat depot that, under physiologic conditions, plays a cardioprotective role. However, excess epicardial adipose tissue has been shown to be associated with prevalence and severity of atrial fibrillation. In arrhythmogenic right ventricular cardiomyopathy and myotonic dystrophy, fibrofatty infiltration of the myocardium is associated with ventricular arrhythmias. In the ovine model of ischemic cardiomyopathy, the presence of intramyocardial adipose or lipomatous metaplasia has been associated with increased propensity to ventricular tachycardia. These observations suggest a role of adipose tissue in the pathogenesis of cardiac arrhythmias. In this article, we review the role of cardiac adipose tissue in various cardiac arrhythmias and discuss the possible pathophysiologic mechanisms.

  12. Cascade Classification with Adaptive Feature Extraction for Arrhythmia Detection.

    PubMed

    Park, Juyoung; Kang, Mingon; Gao, Jean; Kim, Younghoon; Kang, Kyungtae

    2017-01-01

    Detecting arrhythmia from ECG data is now feasible on mobile devices, but in this environment it is necessary to trade computational efficiency against accuracy. We propose an adaptive strategy for feature extraction that only considers normalized beat morphology features when running in a resource-constrained environment; but in a high-performance environment it takes account of a wider range of ECG features. This process is augmented by a cascaded random forest classifier. Experiments on data from the MIT-BIH Arrhythmia Database showed classification accuracies from 96.59% to 98.51%, which are comparable to state-of-the art methods.

  13. Cardiac arrhythmias and conduction defects in systemic sclerosis.

    PubMed

    Vacca, Alessandra; Meune, Christophe; Gordon, Jessica; Chung, Lorinda; Proudman, Susanna; Assassi, Shervin; Nikpour, Mandana; Rodriguez-Reyna, Tatiana S; Khanna, Dinesh; Lafyatis, Robert; Matucci-Cerinic, Marco; Distler, Oliver; Allanore, Yannick

    2014-07-01

    Signs and symptoms of arrhythmias or conduction defects are frequently reported in patients with SSc. These rhythm disorders may have several origins (i.e., related to primary heart involvement, pericardial disease, valvular regurgitation or pulmonary arterial hypertension) and may negatively affect the overall prognosis of these patients. It is therefore important to identify patients at high risk for cardiac arrhythmias with a complete cardiological evaluation and to identify the underlying heart disease, including SSc-related myocardial involvement. In addition, some therapeutic options in SSc patients may differ from those recommended in other populations.

  14. Histopathology and stress biomarkers in the clam Venerupis philippinarum from the Venice Lagoon (Italy).

    PubMed

    Boscolo Papo, Michele; Bertotto, Daniela; Quaglio, Francesco; Vascellari, Marta; Pascoli, Francesco; Negrato, Elena; Binato, Giovanni; Radaelli, Giuseppe

    2014-07-01

    The aim of this study was to evaluate the histomorphology and the stress response in the bivalve Venerupis philippinarum sampled in four differently polluted sites of the Venice Lagoon (Palude del Monte, Marghera, Ca' Roman and Val di Brenta). This species is often used as bioindicator of environmental pollution since it can bioaccumulate a large variety of pollutants because of its filter feeding. Chemical analyses for heavy metals (Cd, Cu, Hg and Pb) and polycyclic aromatic hydrocarbons (PAHs) were performed on whole soft tissues of V. philippinarum. The histological evaluation of clams revealed the presence of Perkinsus sp. infection in animals from all sites, although a very high prevalence of parasites was evidenced in clams from Ca' Roman. Perkinsus sp. were systemically distributed in the mantle, in the intestine and digestive gland, in gonads and gills. The trophozoites of Perkinsus sp. were found isolated or in cluster surrounded by a heavy hemocitical response. Haemocytes always exhibited an immunopositivity to cytochrome P4501A (CYP1A), heat shock protein 70 (HSP70), 4-hydroxy-2-nonenal (HNE) and nitrotyrosine (NT) antibodies. The digestive gland of animals from Palude del Monte showed the highest malondialdehyde (MDA) concentration, whereas clams from Ca' Roman exhibited the highest quantity of metallothioneins.

  15. Mind the costs: rescaling and multi-level environmental governance in Venice lagoon.

    PubMed

    Roggero, Matteo; Fritsch, Oliver

    2010-07-01

    Competences over environmental matters are distributed across agencies at different scales on a national-to-local continuum. This article adopts a transaction costs economics perspective in order to explore the question whether, in the light of a particular problem, the scale at which a certain competence is attributed can be reconsidered. Specifically, it tests whether a presumption of least-cost operation concerning an agency at a given scale can hold. By doing so, it investigates whether the rescaling of certain tasks, aiming at solving a scale-related problem, is likely to produce an increase in costs for day-to-day agency operations as compared to the status quo. The article explores such a perspective for the case of Venice Lagoon. The negative aspects of the present arrangement concerning fishery management and morphological remediation are directly linked to the scale of the agencies involved. The analysis suggests that scales have been chosen correctly, at least from the point of view of the costs incurred to the agencies involved. Consequently, a rescaling of those agencies does not represent a viable option.

  16. Evaluation of Corophium orientale as bioindicator for Venice Lagoon: sensitivity assessment and toxicity-score proposal.

    PubMed

    Picone, Marco; Bergamin, Martina; Novelli Alessandra, Arizzi; Noventa, Seta; Delaney, Eugenia; Barbanti, Andrea; Ghirardini, Annamaria Volpi

    2008-05-01

    The 96-h water-only exposure and 10-d sediment toxicity tests with the amphipod Corophium orientale were performed in order to enhance the knowledge about its overall sensitivity and its applicability to Venice Lagoon sediments. The values obtained with cadmium as reference toxicant demonstrated a certain variability of the LC(50); the higher value was found in spring and the lower in late summer. Tests with other pure chemicals (Ni, Total Ammonia, Sodium Dodecyl-Sulphate) showed good discriminatory power; the toxicity gradient observed was: Cd (LC(50) of 3.3 mg/L)>SDS (LC(50) of 8.7 mg/L)>total ammonia (LC(50) of 126mg/L)>Ni (LC(50) of 352 mg/L). Sediment toxicity test results were used to obtain information on non-treatment factors (grain-size, TOC content) that could act as confounding factors, and to develop a site-specific toxicity-score based on minimum significant difference approach. Confounding factors seem not to affect test results. The procedure to develop the toxicity score took into account the relatively lower sensitivity of C. orientale with respect to other amphipods commonly used in toxicity tests (Ampelisca abdita and Rhepoxynius abronius).

  17. Understanding the association of Escherichia coli with diverse macroalgae in the lagoon of Venice

    NASA Astrophysics Data System (ADS)

    Quero, Grazia M.; Fasolato, Luca; Vignaroli, Carla; Luna, Gian Marco

    2015-06-01

    Recent studies provided evidence that the macroalga Cladopohora in lakes hosts associated Escherichia coli, with consequences on the environmental and human health. We expanded these investigations to other macroalgae (Ulva spp., Sargassum muticum and Undaria pinnatifida) widespread in the lagoon of Venice (Italy). Attached E. coli were abundant, accounting up to 3,250 CFU gram-1 of alga. Macroalgal-associated isolates belonged to all E. coli phylogroups, including pathogenic ones, and to Escherichia cryptic clades. Attached E. coli showed potential to grow even at in situ temperature on macroalgal extracts as only source of carbon and nutrients, and ability to produce biofilm in vitro. The genotypic diversity of the attached isolates was high, with significant differences between algae and the overlying water. Our evidences suggest that attached populations consist of both resident and transient strains, likely resulting from the heterogeneous input of fecal bacteria from the city. We report that cosmopolitan and invasive macroalgae may serve as source of E. coli, including pathogenic genotypes, and that this habitat can potentially support their growth. Considering the global diffusion of the macroalgae here studied, this phenomenon is likely occurring in other coastal cities worldwide and deserves further investigations from either the sanitary and ecological perspectives.

  18. Understanding the association of Escherichia coli with diverse macroalgae in the lagoon of Venice.

    PubMed

    Quero, Grazia M; Fasolato, Luca; Vignaroli, Carla; Luna, Gian Marco

    2015-06-04

    Recent studies provided evidence that the macroalga Cladopohora in lakes hosts associated Escherichia coli, with consequences on the environmental and human health. We expanded these investigations to other macroalgae (Ulva spp., Sargassum muticum and Undaria pinnatifida) widespread in the lagoon of Venice (Italy). Attached E. coli were abundant, accounting up to 3,250 CFU gram(-1) of alga. Macroalgal-associated isolates belonged to all E. coli phylogroups, including pathogenic ones, and to Escherichia cryptic clades. Attached E. coli showed potential to grow even at in situ temperature on macroalgal extracts as only source of carbon and nutrients, and ability to produce biofilm in vitro. The genotypic diversity of the attached isolates was high, with significant differences between algae and the overlying water. Our evidences suggest that attached populations consist of both resident and transient strains, likely resulting from the heterogeneous input of fecal bacteria from the city. We report that cosmopolitan and invasive macroalgae may serve as source of E. coli, including pathogenic genotypes, and that this habitat can potentially support their growth. Considering the global diffusion of the macroalgae here studied, this phenomenon is likely occurring in other coastal cities worldwide and deserves further investigations from either the sanitary and ecological perspectives.

  19. Habitat distribution model for European flounder juveniles in the Venice lagoon

    NASA Astrophysics Data System (ADS)

    Zucchetta, Matteo; Franco, Anita; Torricelli, Patrizia; Franzoi, Piero

    2010-07-01

    In order to identify nursery habitats for Platichthys flesus in the Venice lagoon we developed a generalized additive model relating juvenile flounder's distribution to environmental variables. A field survey was conducted between March 2004 and June 2005 and between February and October 2008 in the central and Northern sub-basins of the lagoon. Each station was sampled by means of a beach seine net and characterized collecting the main chemico-physical variables, such as water temperature, salinity, turbidity, dissolved oxygen content and bottom grain size. Main winds fetches were also considered, and estimated in a GIS environment. A logistic model was fitted, and evaluated on an independent dataset. The response curves allowed to identify the role of the environmental parameters in explaining the distribution of the juvenile flounder: turbidity, salinity and sand content revealed to be the most important factors, showing the preference for mesohaline turbid waters together with a low sand content of the sediment. The application of this model to continuous surfaces of the environmental variables allowed the creation of potential habitat distribution maps. In this way it has been possible to recognize several areas covering a key role for the juveniles of flounder, located mainly in the inner part of the lagoon.

  20. Groundwater flow in the Venice lagoon and remediation of the Porto Marghera industrial area (Italy)

    NASA Astrophysics Data System (ADS)

    Beretta, Giovanni Pietro; Terrenghi, Jacopo

    2016-12-01

    This study aims to determine the groundwater flow in a large area of the Venice (northeast Italy) lagoon that is under great anthropogenic pressure, which is influencing the regional flow in the surficial aquifer (about 30 m depth). The area presents several elements that condition the groundwater flow: extraction by means of drainage pumps and wells; tidal fluctuation; impermeable barriers that define part of the coastline, rivers and artificial channels; precipitation; recharge, etc. All the elements were studied separately, and then they were brought together in a numerical groundwater flow model to estimate the impact of each one. Identification of the impact of each element will help to optimise the characteristics of the Porto Marghera remediation systems. Longstanding industrial activity has had a strong impact on the soil and groundwater quality, and expensive and complex emergency remediation measures in problematic locations have been undertaken to ensure the continuity of industrial and maritime activities. The land reclamation and remediation works withdraw 56-74% of the water budget, while recharge from the river accounts for about 21-48% of the input. Only 21-42% of groundwater in the modelled area is derived from natural recharge sources, untouched by human activity. The drop of the piezometric level due to the realization of the upgradient impermeable barrier can be counteracted with the reduction of the pumping rate of the remediation systems.

  1. Road Asphalt Pavements Analyzed by Airborne Thermal Remote Sensing: Preliminary Results of the Venice Highway

    PubMed Central

    Pascucci, Simone; Bassani, Cristiana; Palombo, Angelo; Poscolieri, Maurizio; Cavalli, Rosa

    2008-01-01

    This paper describes a fast procedure for evaluating asphalt pavement surface defects using airborne emissivity data. To develop this procedure, we used airborne multispectral emissivity data covering an urban test area close to Venice (Italy).For this study, we first identify and select the roads' asphalt pavements on Multispectral Infrared Visible Imaging Spectrometer (MIVIS) imagery using a segmentation procedure. Next, since in asphalt pavements the surface defects are strictly related to the decrease of oily components that cause an increase of the abundance of surfacing limestone, the diagnostic absorption emissivity peak at 11.2μm of the limestone was used for retrieving from MIVIS emissivity data the areas exhibiting defects on asphalt pavements surface.The results showed that MIVIS emissivity allows establishing a threshold that points out those asphalt road sites on which a check for a maintenance intervention is required. Therefore, this technique can supply local government authorities an efficient, rapid and repeatable road mapping procedure providing the location of the asphalt pavements to be checked. PMID:27879765

  2. Understanding the association of Escherichia coli with diverse macroalgae in the lagoon of Venice

    PubMed Central

    Quero, Grazia M.; Fasolato, Luca; Vignaroli, Carla; Luna, Gian Marco

    2015-01-01

    Recent studies provided evidence that the macroalga Cladopohora in lakes hosts associated Escherichia coli, with consequences on the environmental and human health. We expanded these investigations to other macroalgae (Ulva spp., Sargassum muticum and Undaria pinnatifida) widespread in the lagoon of Venice (Italy). Attached E. coli were abundant, accounting up to 3,250 CFU gram−1 of alga. Macroalgal-associated isolates belonged to all E. coli phylogroups, including pathogenic ones, and to Escherichia cryptic clades. Attached E. coli showed potential to grow even at in situ temperature on macroalgal extracts as only source of carbon and nutrients, and ability to produce biofilm in vitro. The genotypic diversity of the attached isolates was high, with significant differences between algae and the overlying water. Our evidences suggest that attached populations consist of both resident and transient strains, likely resulting from the heterogeneous input of fecal bacteria from the city. We report that cosmopolitan and invasive macroalgae may serve as source of E. coli, including pathogenic genotypes, and that this habitat can potentially support their growth. Considering the global diffusion of the macroalgae here studied, this phenomenon is likely occurring in other coastal cities worldwide and deserves further investigations from either the sanitary and ecological perspectives. PMID:26043415

  3. Mind the Costs: Rescaling and Multi-Level Environmental Governance in Venice Lagoon

    PubMed Central

    Fritsch, Oliver

    2010-01-01

    Competences over environmental matters are distributed across agencies at different scales on a national-to-local continuum. This article adopts a transaction costs economics perspective in order to explore the question whether, in the light of a particular problem, the scale at which a certain competence is attributed can be reconsidered. Specifically, it tests whether a presumption of least-cost operation concerning an agency at a given scale can hold. By doing so, it investigates whether the rescaling of certain tasks, aiming at solving a scale-related problem, is likely to produce an increase in costs for day-to-day agency operations as compared to the status quo. The article explores such a perspective for the case of Venice Lagoon. The negative aspects of the present arrangement concerning fishery management and morphological remediation are directly linked to the scale of the agencies involved. The analysis suggests that scales have been chosen correctly, at least from the point of view of the costs incurred to the agencies involved. Consequently, a rescaling of those agencies does not represent a viable option. PMID:20162274

  4. Biodiversity of prokaryotic communities in sediments of different sub-basins of the Venice lagoon.

    PubMed

    Borin, Sara; Brusetti, Lorenzo; Daffonchio, Daniele; Delaney, Eugenia; Baldi, Franco

    2009-06-01

    Microbial community structure and diversity in the wide and shallow Venice lagoon were assessed, prior to construction of mobile dams, at nine stations representative of four different sub-basins previously selected on the basis of international guidelines for sediment quality. The sediments were mainly anoxic and were colonized by microbial communities the species richness of which was quantitatively correlated with total elemental sulfur and acid-volatile sulfide. Automated ribosomal intergenic spacer analysis clustered the stations into three groups. One station for each group was hence analyzed in detail for bacterial and archaeal diversity by screening of 16S rRNA gene clone libraries. The dominance of Gammaproteobacteria clones (84% with a high proportion of Vibrionaceae, indicator of urban pollution) determined significant divergence of the station adjacent to industrial and metropolitan areas. Bacteroidetes were widespread, especially where prairies of aquatic plants are located. The other two analyzed stations were dominated by bacterial taxa implicated in the sulfur cycle: the anoxygenic photosynthetic Chromatiales, sulfate- and sulfur-reducing Desulfobacterales and Desulfuromonadales, and members of the Alpha- and Epsilonproteobacteria.

  5. Postmortem interval (PMI) determined by study sarcophagous biocenoses: three cases from the province of Venice (Italy).

    PubMed

    Turchetto, M; Lafisca, S; Costantini, G

    2001-08-15

    This paper presents and discusses three cases of cadavers found, unburied, in the province of Venice, Northern Italy. In each case, all insect species playing some role in carrion decay processes, both sarcophagous and their predators, found on or in the bodies, were collected and determined. In one case, many larvae of the black soldier fly, Hermetia illucens L. (Diptera: Stratiomyidae) were found and are reported, for the first time in Italy, as necrophagous. Experimental breeding of some fly species was also carried out in controlled temperature and humidity conditions. In particular, it was of interest to know how the Neotropical black soldier fly modified its life-cycle to adapt to a temperate climate. It was thus possible to establish the rate of larval growth and timing of pupation, emergence, oviposition and hatching in various external conditions. The postmortem interval (PMI) established by identifying the life-cycle stages of dipterofauna were later confirmed in all cases through police investigations and the results of forensic analyses.

  6. Tapes philippinarum seed exposure to metals in polluted areas of the Venice lagoon

    NASA Astrophysics Data System (ADS)

    Sfriso, A.; Argese, E.; Bettiol, C.; Facca, C.

    2008-09-01

    The concentration changes of 12 metals (As, Hg, Cd, Cr, Co, Cu, Pb, Mn, Ni, V, Zn, Fe, and Hg) in the soft tissues of Tapes philippinarum during growth were investigated. Clams were seeded in two contaminated areas of the Venice lagoon (San Giuliano and Fusina) and in an area of the Marano lagoon (Lignano Sabbiadoro) close to the clam-farm where the seed was produced. Metal trends were very different according to the considered element, the study site and the growth period. Arsenic was always higher in clam tissues than in surface sediments and suspended particles in all the three stations. Mercury, Cd and Cu were higher in the clams from Marano and Fusina but not in those from San Giuliano. Zinc and Co in clams exceeded the concentrations in the sediment and suspended particles only at Marano. The other elements (Cr, Pb, Mn, Ni, and Fe) were always higher in SPM and sediments. In general metal concentrations in clams were more highly correlated to concentrations in the suspended particles rather than in the surface sediments and in suspended clams rather than in bottom clams, nevertheless significant differences between stations and contaminants were found. Metal concentrations in clams were always lower than the European regulatory limits.

  7. Long-term groundwater dynamics in the coastal confined aquifers of Venice (Italy)

    NASA Astrophysics Data System (ADS)

    Da Lio, Cristina; Tosi, Luigi; Zambon, Giuseppe; Vianello, Andrea; Baldin, Giorgio; Lorenzetti, Giuliano; Manfè, Giorgia; Teatini, Pietro

    2013-12-01

    A more than 40-year monitoring effort has allowed assessment of the long-term evolution of the piezometric levels in the coastal multi-aquifer system of Venice, Italy. We collected, homogenized, and analyzed piezometric data recorded since the early 1970s in wells almost homogeneously distributed in the lagoon area and the adjacent inland. Both the long-term yearly trend and the seasonal evolution of the hydraulic heads of the main artesian aquifers were investigated. It has been observed that the recovering of the water levels has continued over the last decades in the zones affected by aquifer overexploitation mainly during the 1960s. However, the records show that, up till now, the water levels have not grown to the natural values measured in the beginning of the past century. The superposition of a few factors accounts for this. First, the groundwater withdrawals resumed since the 1990s in some areas; then, a reduction of the natural aquifer recharge due to climatic variations. Lastly, the leakage from approximately 400 deep abandoned boreholes in the industrial area, improperly plugged in the 1970s, that are likely to be preferential conduits for groundwater flow toward the shallowest phreatic aquifers.

  8. Polychlorinated naphthalenes in the gas-phase of the Venice Lagoon atmosphere

    NASA Astrophysics Data System (ADS)

    Manodori, L.; Gambaro, A.; Zangrando, R.; Turetta, C.; Cescon, P.

    The gas-phase concentrations of polychlorinated naphthalenes (PCNs) (16 congeners) were investigated over 1 year at two sites in the Venice Lagoon ('marine' and 'industrial') and at a mainland station ('rural'). ΣPCN concentrations were mainly composed of lighter congeners and ranged from 191 to 3415 fg m -3 with values comparable with those of 'background' air. The lowest ΣPCN concentration was detected at the 'marine' site while no significant differences were found between the 'industrial' and 'rural' stations. The presence of combustion marker congeners in most samples suggests that this is the main source of PCN at all sites. The variation of ΣPCN concentrations over the year showed that the highest values occurred from autumn to early spring months at the 'industrial' and 'marine' sites, while at the 'rural' station the values were quite homogeneous, with some peaks in summer. The temperature-PCN relationship was statistically significant only at the 'marine' station, but with a weak correlation. The linear regression between PCN, PAH and PCB, and the seasonal evolution of their ratios was investigated to gain a better understanding of the potential sources of PCNs. At the 'marine' site, it may be supposed that combustion processes constitute PCN sources, with a substantial sea influence. At the 'rural' site, continuous PCN sources from distant points of emission are hypothesized while the 'industrial' site may be supposed to feature an unidentifiable continuous source as well as other seasonal sources.

  9. Temporal distribution of intertidal macrozoobenthic assemblages in a Nanozostera noltii-dominated area (Lagoon of Venice).

    PubMed

    Tagliapietra, D; Pessa, G; Cornello, M; Zitelli, A; Magni, P

    2016-03-01

    We describe the temporal distribution of intertidal macrozoobenthic assemblages in a small marsh pond of the Lagoon of Venice colonized by the seagrass Nanozostera noltii (Hornemman) Tomlinson et Posluzny. Three stations ranging in the degree of N. noltii cover were selected about 100 m apart and sampled 9 times at regular intervals from March 1996 to March 1997. We applied the concepts of resistance and resilience to "natural stress" (e.g. extent of protection from seagrass meadows, exposure of macrozoobenthic assemblages to high temperatures in summer) with the aim to assess the stability of a community along a gradient of seagrass coverage. Results showed that the most structured and taxa-rich macrozoobenthic assemblage occurred at the station covered by a continuous stand of N. noltii, where permanent taxa (i.e. found in 100% of samples) were almost double than those found at the other stations. During the annual cycle, the macrozoobenthic assemblages showed a cyclical pattern, with temporal fluctuations increasing as they moved further away from the seagrass beds. We propose the role of N. noltii offering structural complexity and stability as the more probable explanation to the observed differences between stations in the intertidal assemblages.

  10. Measurement of sputtered efflux from 5-, 8-, and 30-cm diameter mercury ion thrusters

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Mirtich, M. J.

    1975-01-01

    A study was undertaken to investigate the sputtered efflux from 5-, 8-, and 30-cm diameter mercury ion thrusters. Quartz crystal microbalances and fused silica samples were used to analyze the sputtered flux. Spectral transmittance measurements and spectrographic analysis of the samples were made after they were exposed to different thruster effluence by operating the thrusters at various conditions and durations of time. These measurements were used to locate the source of the efflux and determine its accumulated effect at various locations near the thruster. Comparisons of in situ and ex situ transmittance measurements of samples exposed to thruster efflux are also presented.

  11. 78 FR 36787 - Rechanneling the Current Cardiac Risk Paradigm: Arrhythmia Risk Assessment During Drug...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration Rechanneling the Current Cardiac Risk Paradigm: Arrhythmia... the Current Cardiac Risk Paradigm: Arrhythmia Risk Assessment During Drug Development Without...

  12. Acute cardiac arrhythmias following surgery for congenital heart disease: mechanisms, diagnostic tools, and management.

    PubMed

    Payne, Linda; Zeigler, Vicki L; Gillette, Paul C

    2011-06-01

    This article focuses on the management of those cardiac arrhythmias most commonly seen in the immediate postoperative period. They include ventricular tachycardia, ventricular fibrillation, atrial flutter, junctional ectopic tachycardia, bradycardia, and atrioventricular block. The mechanisms of cardiac arrhythmias are reviewed followed by a brief overview of the predominant acute arrhythmias, tools used for the diagnostic evaluation of these arrhythmias, management strategies, and, finally, nursing considerations.

  13. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  14. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  15. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  16. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  17. 21 CFR 870.1025 - Arrhythmia detector and alarm (including ST-segment measurement and alarm).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Arrhythmia detector and alarm (including ST... Diagnostic Devices § 870.1025 Arrhythmia detector and alarm (including ST-segment measurement and alarm). (a) Identification. The arrhythmia detector and alarm device monitors an electrocardiogram and is designed to...

  18. Exercise and Arrhythmias: A Double-Edged Sword.

    PubMed

    Manolis, Antonis S; Manolis, Antonis A

    2016-07-01

    Ample evidence indicates that moderate regular exercise is beneficial for both normal individuals and patients with cardiovascular (CV) disease. However, intense and strenuous exercise in individuals with evident or occult underlying CV abnormalities may have adverse effects with provocation and exacerbation of arrhythmias that may lead to life-threatening situations. Both of these aspects of exercise-induced effects are herein reviewed.

  19. Channelopathies - Emerging Trends in The Management of Inherited Arrhythmias

    PubMed Central

    Chockalingam, Priya; Mizusawa, Yuka; Wilde, Arthur A.M.

    2016-01-01

    In spite of their relative rarity, inheritable arrhythmias have come to the forefront as a group of potentially fatal but preventable cause of sudden cardiac death in children and (young) adults. Comprehensive management of inherited arrhythmias includes diagnosing and treating the proband and identifying and protecting affected family members. This has been made possible by the vast advances in the field of molecular biology enabling better understanding of the genetic underpinnings of some of these disease groups, namely congenital long QT syndrome, catecholaminergic polymorphic ventricular tachycardia and Brugada syndrome. The ensuing knowledge of the genotype-phenotype correlations enables us to risk-stratify, prognosticate and treat based on the genetic test results. The various diagnostic modalities currently available to us, including clinical tools and genetic technologies, have to be applied judiciously in order to promptly identify those affected and to spare the emotional burden of a potentially lethal disease in the unaffected individuals. The therapeutic armamentarium of inherited arrhythmias includes pharmacological agents, device therapies and surgical interventions. A treatment strategy keeping in mind the risk profile of the patients, the local availability of drugs and the expertise of the treating personnel is proving effective. While opportunities for research are numerous in this expanding field of medicine, there is also tremendous scope for incorporating the emerging trends in managing patients and families with inherited arrhythmias in the Indian subcontinent. PMID:25852242

  20. Reduction in dynamin-2 is implicated in ischaemic cardiac arrhythmias.

    PubMed

    Shi, Dan; Xie, Duanyang; Zhang, Hong; Zhao, Hong; Huang, Jian; Li, Changming; Liu, Yi; Lv, Fei; The, Erlinda; Liu, Yuan; Yuan, Tianyou; Wang, Shiyi; Chen, Jinjin; Pan, Lei; Yu, Zuoren; Liang, Dandan; Zhu, Weidong; Zhang, Yuzhen; Li, Li; Peng, Luying; Li, Jun; Chen, Yi-Han

    2014-10-01

    Ischaemic cardiac arrhythmias cause a large proportion of sudden cardiac deaths worldwide. The ischaemic arrhythmogenesis is primarily because of the dysfunction and adverse remodelling of sarcolemma ion channels. However, the potential regulators of sarcolemma ion channel turnover and function in ischaemic cardiac arrhythmias remains unknown. Our previous studies indicate that dynamin-2 (DNM2), a cardiac membrane-remodelling GTPase, modulates ion channels membrane trafficking in the cardiomyocytes. Here, we have found that DNM2 plays an important role in acute ischaemic arrhythmias. In rat ventricular tissues and primary cardiomyocytes subjected to acute ischaemic stress, the DNM2 protein and transcription levels were markedly down-regulated. This DNM2 reduction was coupled with severe ventricular arrhythmias. Moreover, we identified that the down-regulation of DNM2 within cardiomyocytes increases the action potential amplitude and prolongs the re-polarization duration by depressing the retrograde trafficking of Nav1.5 and Kir2.1 channels. These effects are likely to account for the DNM2 defect-induced arrhythmogenic potentials. These results suggest that DNM2, with its multi-ion channel targeting properties, could be a promising target for novel antiarrhythmic therapies.

  1. Infant Visual Sustained Attention and Respiratory Sinus Arrhythmia.

    ERIC Educational Resources Information Center

    Richards, John E.

    1987-01-01

    Tested the model which posits that heart-rate deceleration and respiratory sinus arrhythmia are indices of infant attention. Infants studied cross-sectionally at 14, 20, and 26 weeks of age were presented with complex patterns on a TV screen which were accompanied by an "interrupting stumulus". (Author/BN)

  2. Fetal cardiac arrhythmia detection and in utero therapy

    PubMed Central

    Strasburger, Janette F.; Wakai, Ronald T.

    2010-01-01

    The human fetal heart develops arrhythmias and conduction disturbances in response to ischemia, inflammation, electrolyte disturbances, altered load states, structural defects, inherited genetic conditions, and many other causes. Yet sinus rhythm is present without altered rate or rhythm in some of the most serious electrophysiological diseases, which makes detection of diseases of the fetal conduction system challenging in the absence of magnetocardiographic or electrocardiographic recording techniques. Life-threatening changes in QRS or QT intervals can be completely unrecognized if heart rate is the only feature to be altered. For many fetal arrhythmias, echocardiography alone can assess important clinical parameters for diagnosis. Appropriate treatment of the fetus requires awareness of arrhythmia characteristics, mechanisms, and potential associations. Criteria to define fetal bradycardia specific to gestational age are now available and may allow detection of ion channelopathies, which are associated with fetal and neonatal bradycardia. Ectopic beats, once thought to be entirely benign, are now recognized to have important pathologic associations. Fetal tachyarrhythmias can now be defined precisely for mechanism-specific therapy and for subsequent monitoring of response. This article reviews the current and future diagnostic techniques and pharmacologic treatments for fetal arrhythmia. PMID:20418904

  3. Severe Hypothermia Causing Ventricular Arrhythmia in Organophosphorus Poisoning.

    PubMed

    Munta, Kartik; Santosh, Paiullah; Surath, Manimala Rao

    2017-02-01

    Organophosphorus poisoning cases are routinely treated across all Intensive Care Units adjoining the rural areas where agriculture is the main source of income. We present a unique case of severe hypothermia seen in a case of organophosphorus poisoning, which led to electrocardiogram disturbances and life-threatening arrhythmias.

  4. Ventricular arrhythmia incidence in the rat is reduced by naloxone.

    PubMed

    Pugsley, M K; Hayes, E S; Wang, W Q; Walker, M J A

    2015-07-01

    This study characterized the antiarrhythmic effects of the opioid receptor antagonist naloxone in rats subject to electrically induced and ischemic arrhythmias. Naloxone (2, 8 and 32 μmol/kg/min) was examined on heart rate, blood pressure, and the electrocardiogram (EKG) as well as for effectiveness against arrhythmias produced by occlusion of the left anterior descending coronary artery or electrical stimulation of the left ventricle. Naloxone reduced blood pressure at the highest dose tested while heart rate was dose-dependently reduced. Naloxone dose-dependently prolonged the P-R and QRS intervals and increased the RSh amplitude indicative of effects on cardiac sodium (Na) channels. Naloxone prolonged the Q-T interval suggesting a delay in repolarization. Naloxone effects were comparable to the comparator quinidine. Naloxone (32 μmol/kg/min) reduced ventricular fibrillation (VF) incidence to 38% (from 100% in controls). This same dose significantly increased the threshold for induction of ventricular fibrillation (VFt), prolonged the effective refractory period (ERP) and reduced the maximal following frequency (MFF). The patterns of ECG changes, reduction in ischemic arrhythmia (VF) incidence and changes in electrically induced arrhythmia parameters at high doses of naloxone suggest that it directly blocks cardiac Na and potassium (K) ion channels.

  5. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.

    PubMed

    Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios

    2013-07-31

    Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies.

  6. Severe Hypothermia Causing Ventricular Arrhythmia in Organophosphorus Poisoning

    PubMed Central

    Munta, Kartik; Santosh, Paiullah; Surath, Manimala Rao

    2017-01-01

    Organophosphorus poisoning cases are routinely treated across all Intensive Care Units adjoining the rural areas where agriculture is the main source of income. We present a unique case of severe hypothermia seen in a case of organophosphorus poisoning, which led to electrocardiogram disturbances and life-threatening arrhythmias. PMID:28250607

  7. Atrial Arrhythmias in Astronauts - Summary of a NASA Summit

    NASA Technical Reports Server (NTRS)

    Barr, Yael R.; Watkins, Sharmila D.; Polk, J. D.

    2010-01-01

    Background and Problem Definition: To evaluate NASA s current standards and practices related to atrial arrhythmias in astronauts, Space Medicine s Advanced Projects Section at the Johnson Space Center was tasked with organizing a summit to discuss the approach to atrial arrhythmias in the astronaut cohort. Since 1959, 11 cases of atrial fibrillation, atrial flutter, or supraventricular tachycardia have been recorded among active corps crewmembers. Most of the cases were paroxysmal, although a few were sustained. While most of the affected crewmembers were asymptomatic, those slated for long-duration space flight underwent radiofrequency ablation treatment to prevent further episodes of the arrhythmia. The summit was convened to solicit expert opinion on screening, diagnosis, and treatment options, to identify gaps in knowledge, and to propose relevant research initiatives. Summit Meeting Objectives: The Atrial Arrhythmia Summit brought together a panel of six cardiologists, including nationally and internationally renowned leaders in cardiac electrophysiology, exercise physiology, and space flight cardiovascular physiology. The primary objectives of the summit discussions were to evaluate cases of atrial arrhythmia in the astronaut population, to understand the factors that may predispose an individual to this condition, to understand NASA s current capabilities for screening, diagnosis, and treatment, to discuss the risks associated with treatment of crewmembers assigned to long-duration missions or extravehicular activities, and to discuss recommendations for prevention or management of future cases. Summary of Recommendations: The summit panel s recommendations were grouped into seven categories: Epidemiology, Screening, Standards and Selection, Treatment of Atrial Fibrillation Manifesting Preflight, Atrial Fibrillation during Flight, Prevention of Atrial Fibrillation, and Future Research

  8. Amiodarone in the treatment of refractory supraventricular and ventricular arrhythmias

    PubMed Central

    Wheeler, P. J.; Ingram, D. V.; Puritz, R.; Chamberlain, D. A.

    1979-01-01

    Amiodarone is an antiarrhythmic agent unrelated to other drugs in current use. It has been little used in Britain, and no formal clinical trials have been possible because the drug has not been licensed by the Committee on Safety of Medicines. Nevertheless it has unique properties which can be valuable in the treatment of a wide spectrum of arrhythmias, particularly supraventricular tachycardias. Amiodarone has a slow onset of action and is cumulative. A sustained action is therefore achieved without the need for frequent maintenance dosage. Fifty patients have been treated with amiodarone in maintenance doses ranging from 200 mg on alternate days to 200 mg twice daily either alone, or in combination with conventional therapy. All were resistant to conventional therapy alone or could not be treated with usual agents because of unwanted drug effects. Of 27 patients with supraventricular arrhythmias, 18 were completely controlled and the other 9 were markedly improved. Six of 8 patients with recurrent life-threatening ventricular arrhythmias were well controlled symptomatically. Results were predictably less satisfactory in 15 high risk post-infarction patients with malignant arrhythmias and severe myocardial damage, but 6 were probably improved as a result of amiodarone. All patients on maintenance therapy for 3 months or more developed corneal microdeposits. None has any visual symptoms or other ocular defect, and treatment has not been curtailed as a result of this well recognized effect which is believed to be reversible and benign. Amiodarone can control patients with otherwise refractory arrhythmias including some which are life-threatening. Formal clinical trials are needed to define accurately its future role in the prevention and treatment of serious rhythm disorders of the heart. PMID:432163

  9. Association between Hypophosphatemia and Cardiac Arrhythmias in the Early Stage of Sepsis: Could Phosphorus Replacement Treatment Reduce the Incidence of Arrhythmias?

    PubMed

    Schwartz, Andrei; Brotfain, Evgeni; Koyfman, Leonid; Kutz, Ruslan; Gruenbaum, Shaun E; Klein, Moti; Zlotnik, Alexander

    2014-06-01

    It is well known that new-onset arrhythmias are common in septic patients. It is thought that hypophosphatemia in the early stages of sepsis may contribute to the development of new arrhythmias. In this study, we hypothesized that intravenous (IV) phosphorus replacement may reduce the incidence of arrhythmias in critically ill patients. 34 adult septic patients with hypophosphatemia admitted to the general intensive care unit were treated with IV phosphorus replacement per ICU protocol, and the incidence of new arrhythmias were compared with 16 patients from previously published data. IV phosphorus replacement was associated with a significantly reduced incidence of arrhythmias (38% vs. 63%, p=0.04). There were no differences in observed mortality between subgroups, which may be due to the small sample size. This study demonstrated that IV phosphorus replacement might be effective in reducing the incidence of new arrhythmias in septic patients.

  10. Response Of A Tidal Environment To Changes In The Forcing: Insights From The Southern Venice Lagoon (Italy)

    NASA Astrophysics Data System (ADS)

    Roner, M.; D'Alpaos, A.; Ghinassi, M.; Fedi, M.; Bellucci, L. G.; Vigliotti, L.

    2014-12-01

    The Venice Lagoon represents an outstanding example of man-landscape co-existence, where salt marshes are currently exposed to possibly irreversible transformations due to the effects of climate changes and human activity. The increasing rate of relative sea level rise and the decreasing sediment supply are the dominant forcings controlling salt-marshes survival, as in other cases worldwide. Analysing signatures of landscape changes in the stratigraphic record is crucial to refine our knowledge of tidal landform dynamics and it is a first step to develop predictive morphodynamic models. The southern Venice lagoon is suited to analyze the response of tidal landscape to changes in environmental forcing. The upper part of the Holocene sedimentary succession accumulated as the effect of a "human-induced transgression", which caused a considerable salt-marshes contraction since the 16th century. In the southern Venice lagoon, re-directions of the Brenta River during 16th and the 19th century caused significant changes in terms of freshwater and sediment supply. To analyze the paleomorphodynamic response to these main changes, we collected 25 cores (1.0 to 1.5 m deep) along a NE-SW linear transect about 5 km long cutting through salt-marsh, tidal-flat and subtidal-platform deposits. Through sedimentological analyses we defined the spatial arrangement of swamp, salt-marsh, wave-worked and tidal-flat mud deposits along this transect. Magnetic susceptibility and organic/inorganic content were measured in the study succession, which was dated through 14C and 137Cs geochronological analyses. Our results suggest that salt-marsh sedimentation occurred above deltaic deposits since the 14th century. Salt-marsh aggradation stemmed out from both mud settling and organic accumulation, although magnetic susceptibility revealed some intervals during which the inorganic deposition dominates over organic accumulation. Salt-marsh aggradation occurred in parallel with the decrease in salt

  11. Measuring the economic value of alternative clam fishing management practices in the Venice Lagoon: results from a conjoint valuation application

    NASA Astrophysics Data System (ADS)

    Nunes, Paulo A. L. D.; Rossetto, Luca; de Blaeij, Arianne

    2004-11-01

    This article focuses on the economic valuation of alternative clam management practices in the Venice Lagoon. The proposed valuation method is characterized by the design of a survey questionnaire applied to the fishermen population. In each questionnaire, two fishing alternatives are described. The respondent is asked to choose one of them. This valuation method, referred in the article as conjoint valuation, gives sufficient flexibility to set, alter, and combine the valuation of different clam management practices. Furthermore, this approach presents an important advantage to the well-known contingent valuation method since it makes the monetary valuation of each management attribute possible. Estimation results show that all three attributes used in the questionnaire to describe and value different clam management practices—price of the annual permit and fishing technological system—are statistically robust, indicating that fishermen bear a utility change whenever these attributes change. In particular, fishermen's willingness to pay for a larger clam fishing area ranges between 568 and 811 € per year. In addition, an individual's willingness to pay for a fishing practice exclusively based on the vibrant rake system ranges between 1005 and 2456 €. Finally, the adoption of a clam fish management practice in the Venice Lagoon that is exclusively based on the use of manual rakes, which is associated with the lowest damage to the lagoon ecosystem, will represent a welfare loss of 5904 € per fisherman per year. Combining such a value estimate with the total number of fishermen currently operating in the Lagoon of Venice, the welfare loss associated with the adoption of this type of clam management policy amounts to 11.8 € million per year. This figure can be regarded as an upper bound to the cost of implementation of a clam fishing system anchored in the use of manual, ecosystem friendly rakes.

  12. Increased stream discharge after the 3 September 2016 Mw 5.8 Pawnee, Oklahoma earthquake

    NASA Astrophysics Data System (ADS)

    Manga, Michael; Wang, Chi-Yuen; Shirzaei, Manoochehr

    2016-11-01

    Earthquakes influence hydrogeological processes and properties in Earth's crust, some of which affect surface waters. We document increased discharge in a stream after the 3 September 2016 Mw 5.8 earthquake near Pawnee, Oklahoma, an event likely induced by underground wastewater disposal. Discharge increased by an order of magnitude and remained elevated until the change was obscured by rain 1 week later. Given the earthquake magnitude and distance from the stream, by comparison with previous examples of responses to earthquakes, increased discharge after this earthquake is expected. While the mechanism increasing discharge cannot be confirmed, the observations require changes in physical properties of the subsurface. Fluid injection may thus influence hydrogeological properties of shallow groundwater systems and aquifers indirectly by inducing seismicity, if the induced seismic events are large enough.

  13. Initial assessment of the intensity distribution of the 2011 Mw5.8 Mineral, Virginia, earthquake

    USGS Publications Warehouse

    Hough, Susan E.

    2012-01-01

    The intensity data collected by the U.S. Geological Survey (USGS) "Did You Feel It?" (DYFI) Website (USGS, DYFI; http://earthquake.usgs.gov/earthquakes/dyfi/events/se/082311a/us/index.html, last accessed Sept 2011) for the Mw5.8 Mineral, Virginia, earthquake, are unprecedented in their spatial richness and geographical extent. More than 133,000 responses were received during the first week following the earthquake. Although intensity data have traditionally been regarded as imprecise and generally suspect (e.g., Hough 2000), there is a growing appreciation for the potential utility of spatially rich, systematically determined DYFI data to address key questions in earthquake ground-motions science (Atkinson and Wald, 2007; Hauksson et al., 2008).

  14. Dependence of 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen photoaddition on the conformation of ribonucleic acid

    SciTech Connect

    Thompson, J.F.; Bachellerie, J.P.; Hall, K.; Hearst, J.E.

    1982-03-16

    The photoaddition of 4'-(hydroxymethyl)-4,5',8-trimethylpsoralen (HMT) to different conformational states of RNA was studied. Poly(U), poly(A,U) (random copolymer), poly(A-U) (alternating copolymer), poly(A)-poly(U) (double stranded), and poly(U)-poly(A)-poly(U) (triple stranded) were reacted with HMT at different temperatures and salt concentrations. The conformation of the polymers was monitored by UV absorption and circular dichroism. It was found that the rate of HMT photoaddition changed dramatically at structural transitions in the RNA. The alternating copolymer poly(A-U) was found to have the highest rate of addition. Low salt and temperature produced maximal incorporation.

  15. Development of a 14-vane, double-strapped, 5.8-GHz magnetron oscillator

    NASA Astrophysics Data System (ADS)

    Choi, Jin Joo; Lee, Han Seoul; Jang, Kwang Ho; Sim, Sung Hun; Choi, Heung Sik

    2016-08-01

    Experiments on a 14-vane, double-strapped magnetron oscillator were performed to demonstrate high-power, high-efficiency coherent radiation at 5.8 GHz. The double-strapped magnetron was designed by using the Buneman-Hatree resonance condition, electromagnetic simulations and non-linear three-dimensional particle-in-cell (PIC) simulations. Experiments showed an oscillation output power of 5.3 kW at 5.79 GHz, corresponding to a DC-RF conversion efficiency of 57%. The cathode voltage was 9.2 kV, the collected anode current was 1 A, and the external magnetic field is 7.5 kG. Experimental results for the RF power, oscillation frequency, and efficiency were in good agreement with the corresponding values from non-linear three-dimensional PIC simulations.

  16. "The Root is Hidden and the Material Uncertain": the challenges of prosecuting witchcraft in early modern Venice.

    PubMed

    Seitz, Jonathan

    2009-01-01

    The rich archival records of the Holy Office of the Inquisition in Venice have yielded much information about early modern society and culture. The transcripts of witchcraft trials held before the Inquisition reveal the complexities of early modern conceptions of natural and supernatural. The tribunal found itself entirely unable to convict individuals charged with performing harmful magic, or maleficio, as different worldviews clashed in the courtroom. Physicians, exorcists, and inquisitors all had different approaches to distinguishing natural phenomena from supernatural, and without a consensus guilty verdicts could not be obtained.

  17. The land subsidence of the Venice historical center: twenty years of monitoring by SAR-based interferometry

    NASA Astrophysics Data System (ADS)

    Tosi, L.; Strozzi, T.; Teatini, P.

    2012-12-01

    The subsidence of Venice, one of the most beautiful and famous cities in the world, is well known not by reason of the magnitude of the ground movement, which amounts to less than 15 cm over the last century, but because it has seriously compromised the ground safety level of the city in relation of its small elevation above the sea. The lowering of Venice is still today a subject of debates with large rumours on press releases every time a scientific paper is published on the topic. Over the last two decades, satellites instrumented with SAR sensors provided excellent data for detecting land displacements by inteferometric processing. In particular, the accuracy achieved by Persistent Scatterer Interferometry (PSI) and the impressive number of detected measurement points have progressively reduced the use of in situ traditional measurements, i.e. leveling survey, for monitoring land displacements of Venice. In fact, the intensive urban development makes the historical center an optimal site for PSI. On the other hand, the correct interpretation of the PSI outcomes, which provide the relative movement of single churches, palaces, bridges with millimetric precision and metric spatial resolution, require a deep knowledge of the city and its subsoil due to the peculiarity of this urban area developed over the centuries within the sea. We investigate the movements of Venice by Interferometric Point Target Analysis (IPTA) over the last 20 years using SAR acquisitions of the ERS-1/2, ENVISAT, TerraSAR-X, and Cosmo-SkyMed satellites. The density of detected scatterers is one order of magnitude larger with the newest very high resolution X-band sensors from TerraSAR-X and Cosmo-SkyMed, but by reason of the larger observation period the accuracy of the mean displacement rate of the C-band ERS and ENVISAT is higher. IPTA results have been calibrated using leveling and permanent GPS stations to correct the so-called flattening problem, i.e. the slight phase tilt resulting by

  18. Remote sensing retrieval of water constituents in shallow coastal waters with applications to the Venice lagoon

    NASA Astrophysics Data System (ADS)

    Zhou, X.; Marani, M.; Albertson, J. D.; Silvestri, S.

    2013-12-01

    Lagoons and estuaries worldwide are experiencing accelerated ecosystem degradation due to increased direct and indirect anthropogenic pressure. Monitoring the environmental state and trends in such environment would benefit from the use of remote sensing techniques, which can access a wide range of spatial and temporal scales. However, most remote sensors are not suitable for monitoring shallow and optically-complex waters, because of their low spatial and spectral-resolution and of the uncertainties associated with the contribution of the bottom sediment to the observed remote sensing signal. We apply here a remote sensing-based approach to mapping suspended sediment and chlorophyll concentrations in the shallow Venice lagoon, which integrates hyperspectral remote sensing data, a simplified radiative transfer model, and in-situ water quality measurements. First, we calibrate and validate the key parameters of the model, such as bottom albedo and absorption/backscattering coefficients of sediment, by comparing remote sensing derived water constituent concentrations with in-situ data. We then determine the statistics of those parameters, and the associated estimation uncertainty, by applying a bootstrapping technique. Finally, the lagoon-wide distribution of water constituent concentrations, and of the estimation uncertainty, is derived by inverting the model. The estimates are consistent with measured concentrations and their known optical properties, particularly for the suspended sediment concentrations, while chlorophyll concentration estimates remain more uncertain. Our analyses show that remote sensing methods can provide reliable water constituent concentrations at the system scale and that uncertainties become overwhelming only in particularly shallow areas (water depths indicatively lower than 1 m in the present application). Importantly, the joint use of radiative transfer models, in situ observations, and statistical techniques allows the production of

  19. Understanding relationships between morphology and ecosystem structure in a shallow tidal basins of Venice lagoon

    NASA Astrophysics Data System (ADS)

    Giuseppina Persichillo, Maria; Taramelli, Andrea; Valentini, Emiliana; Filipponi, Federico; Meisina, Claudia; Zucca, Francesco

    2014-05-01

    Coastal wetlands represent complex ecosystems prone to continue fluctuation of their internal equilibrium. They are valuable natural resources characterized by the continue interactions between geomorphological and biological components. Their adaptation to changing conditions is highly dependent on the rate and extent of spatial and temporal processes and their responses are still poorly understood. According to this, the vulnerability assessment to natural and human made hazard have became fundamental to analyse the resilience of these areas, their ability to cope with the impacts from externally driven forces or the efforts needed to minimize the impacts (Gitay et al., 2011). The objective of this research is to develop a comprehensive and replicable method through the application of Multi-Source data analysis, based on the integration of Earth Observation data and field survey, to analyse a shallow tidal basin of salt marshes, located in the northern part of the Venice lagoon. The study site is characterised by relatively elevated areas colonized by halophytic vegetation, and tidal flats, with not vegetated areas, characterized by lower elevations. Sub-pixel processing techniques (Spectral Mixing Analysis - SMA) were used to analyse the spatial distribution of both vegetation and sediments typology. Furthermore the classifications were assayed in terms of spatial (Power law) and temporal (Empirical Orthogonal Functions) patterns, in order to find the main characteristics of the aforementioned spatial trends and their variation over time. The principal aim is to study the spatio-temporal evolution of this coastal wetland area, in order to indentify tipping points, namely thresholds, beyond which the system reaches critical state and the main climatic, hydrodynamic and morphological variables that may influence and increase this behaviour. This research represents a new approach to study the geomorphological processes and to improve the management and

  20. Aerosol fine fraction in the Venice Lagoon: Particle composition and sources

    NASA Astrophysics Data System (ADS)

    Prodi, F.; Belosi, F.; Contini, D.; Santachiara, G.; Di Matteo, L.; Gambaro, A.; Donateo, A.; Cesari, D.

    2009-04-01

    The work presents a characterisation of aerosol sampled during three campaigns conducted in the Venice Lagoon from 30 June to 21 July 2004, from 15 February to 10 March 2005 and from 8 May to 25 May 2006. The results yield information about the physical-chemical characteristics of fine aerosol, the possible sources and its fate. Sulphate (SO 42-), nitrate (NO 3-) and ammonium (NH 4+) are identified as the main water soluble components. The sum of these ions in the spring campaign 2006 varies from 51% to nearly 100% of PM2.5 fraction aerosol. NH 4+ is found to be significantly correlated to non-sea-salt sulphate (nss-SO 42-) and NO 3-, thus indicating the prevalent presence of ammonium nitrate and sulphate. The overall lack of a clear diurnal and seasonal cycle of sulphate suggests a transport from the Po Valley, while the diurnal and seasonal profile of nitrate concentrations suggests a prevalence of local generation. Sulphates from sea water through oxidation of dimethylsulfide (DMS) are not negligible (about 10% of the anthropogenic sulphate). The marine aerosol contribution to PM1 and PM2.5 fractions, calculated using Na + as a tracer of sea-salts, is low (range 1-6%). In some cases chlorine depletion is observed. The content of chlorine in the aerosol particle is mostly higher than expected for marine environments (considered on the basis of Cl -/Na + ratio). Therefore, specific sources for the element have been suggested. Oxalic acid anion, which accounts for 55% of the organic compounds examined, presents mean values 180 ng m - 3 and 161 ng m - 3 in the winter and spring campaigns, comparable with reported values in low polluted urban areas. In the winter campaign there is a high correlation between formate and acetate ( R2 = 0.93), suggesting that a common source makes a high contribution to the measured concentrations.

  1. 31 CFR 5.8 - When will Treasury entities suspend or terminate debt collection on a Treasury debt?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false When will Treasury entities suspend or terminate debt collection on a Treasury debt? 5.8 Section 5.8 Money and Finance: Treasury Office of the Secretary of the Treasury TREASURY DEBT COLLECTION Procedures To Collect Treasury Debts §...

  2. 18 CFR 5.8 - Notice of commencement of proceeding and scoping document, or of approval to use traditional...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... alternative procedures. 5.8 Section 5.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE FEDERAL POWER ACT INTEGRATED LICENSE APPLICATION...) The decision of the Director of the Office of Energy Projects on any request to use the...

  3. Risk of ventricular arrhythmias associated with nonsedating antihistamine drugs

    PubMed Central

    José de Abajo, Francisco; Rodríguez, Luis Alberto García

    1999-01-01

    Aims To quantify and compare the incidence of ventricular arrhythmias associated with the use of five nonsedating antihistamines: acrivastine, astemizole, cetirizine, loratadine and terfenadine. The effects of age, sex, dose, duration of treatment, and the interaction with P450 inhibitor drugs were also examined. Methods We carried out a cohort study with a nested case-control analysis using the UK-based General Practice Research Database (GPRD). The study cohort included persons aged less than 80 years old who received their first prescription for any of the five study drugs between January 1, 1992 and September 30, 1996. We estimated relative risks and 95% confidence intervals of idiopathic ventricular arrhythmias with current use of antihistamines as compared with non use. Results The study cohort included 197 425 persons who received 513 012 prescriptions. Over the study period 18 valid cases of idiopathic ventricular arrhythmias were detected. Nine occurred during the current use of any antihistamine, resulting in a crude incidence of 1.9 per 10 000 person-years (95%CI: 1.0–3.6) and a relative risk of 4.2 (95%CI: 1.5–11.8) as compared with non use. Astemizole presented the highest relative risk (RR = 19.0; 95%CI: 4.8–76.0) of all study drugs, while terfenadine (RR = 2.1; 95%CI:0.5–8.5) was in the range of other nonsedating antihistamines. Older age was associated with a greater risk of ventricular arrhythmias (RR = 7.4; 95%CI: 2.6–21.4) and seemed to increase the effect of antihistamines (RR = 6.4; 95%CI: 1.7–24.8). The proportions of high dose terfenadine and the concomitant use with P450 inhibitors among current users of terfenadine were 2.7% and 3.4%, respectively over the study period with no single case of ventricular arrhythmias occurring in the presence of these two risk factors. Conclusions The use of nonsedating antihistamines increases the risk of ventricular arrhythmias by a factor of four in the general population. Yet, the absolute

  4. COSMO-SkyMed vs RADARSAT-2 for Monitoring Natural and Anthropogenic Components of the Land Movement in Venice

    NASA Astrophysics Data System (ADS)

    Tosi, Luigi; Da Lio, Cristina; Strozzi, Tazio; Teatini, Pietro

    2016-08-01

    We present the result of a test aimed at evaluating the capability of RADARSAT-2 and COSMO-SkyMed to map the natural subsidence and ground movements induced by anthropogenic activities in the historical center of Venice. Firstly, ground movements have been retrieved at quite long- and short-term by the Persistent Scattered Interferometry (PSI) on 2008-2015 RADARSA T-2 and 2013-2015 COSMO-SkyMed image stacks, respectively. Secondly, PSI has been calibrated at regional scale using the records of permanent GPS stations. Thirdly, considering that over the last two decades "in the historical center of Venice" natural land movements are primarily ascribed to long- term processes, and those induced by human activities act at short-term, we have properly resampled 83-month RADARSA T-2 C-band and 27-month COSMO- SkyMed X-band interferometric products by a common grid and processed the outcome to estimate the two components of the displacements. Results show that the average natural subsidence is generally in the range of 0.9 - 1.1 mm/yr and the anthropogenic ground movements are up to 2 mm/yr.

  5. Regulation of the fishing activities in the lagoon of Venice, Italy: Results from a socio-economic study

    NASA Astrophysics Data System (ADS)

    Nunes, Paulo A. L. D.; Silvestri, Silvia; Pellizzato, Michele; Boatto, Vasco

    2008-10-01

    In the last years, the overall fish industry in the lagoon of Venice has shown a gradual decline. In order to better understand this process, we carry out a socio-economic questionnaire next to the fisherman population. Questionnaire contains significant qualitative and quantitative data that allow us to evaluate the social and the cultural profile of the respondents, including information with respect to the different technological fishing characteristics involved, type and amount of the species harvested as well as the overall productivity of the activity. Furthermore, the questionnaire contains an economic valuation exercise so as to assess in monetary terms the preferences of the fishermen with respect to different alternative policy options that may characterize a future regulation of this economic activity. Estimation results show that fishermen welcome any regulation initiative that is characterized by: (1) banning all fishing activities during the night, (2) allocating fishing concessions areas to each fishermen in a way that minimize the distance between the fishing area and the harbor, and (3) by introducing of a labeling mechanism that certifies the origin of the product. Moreover, the underlying economic valuation mechanism reveals to sensitive to respondent's motivational profile, including the overall trust and confidence that fisherman community places on the current institutional bodies. This result reveals to be of particular significance when attempting the design of an efficient, widely supported regulation of the fishing activity in the lagoon of Venice.

  6. Biomonitoring approach with mussel Mytilus galloprovincialis (Lmk) and clam Ruditapes philippinarum (Adams and Reeve, 1850) in the Lagoon of Venice.

    PubMed

    Moschino, Vanessa; Delaney, Eugenia; Meneghetti, Francesca; Ros, Luisa Da

    2011-06-01

    Transplanted Mytilus galloprovincialis and native Ruditapes philippinarum were deployed in 10 sampling stations with different pollution impact within the Lagoon of Venice to evaluate the temporal variations and the suitability of the following cytochemical and histochemical biomarkers just as indicators of environmental stress: lysosomal membrane stability, lipofuscins, neutral lipids and lysosome to cytoplasm volume ratio. The physiological status of the organisms was also investigated by determining the survival in air capability and the reburrowing rate (clams). The biological parameters were assessed in June and October. Furthermore, for a better definition of the environmental aspects of the study sites, heavy metal, PAH and PCB concentrations were also evaluated in the sediments. As a whole, the biological responses examined in both species from all the sampling sites showed significant differences between the two seasonal campaigns, only lysosomal membrane stability exhibited less variability. Pollutants in sediments generally showed low-intermediate contamination levels, few hotspots persisting mostly in the inner areas of the lagoon, the most influenced by the industrial zone. Transplanted mussels were more responsive than native clams and the biological responses of both species varied temporally. The range of the spatial variability was always narrow and reflected only partially the broader variability shown by the chemical content in the sediments. In this sense, biological responses seemed to be particularly influenced by the high temporal and spatial heterogeneity that characterise the Lagoon of Venice, as well as most of the transitional environments.

  7. Annual growth and environmental relationships of the invasive species Sargassum muticum and Undaria pinnatifida in the lagoon of Venice

    NASA Astrophysics Data System (ADS)

    Sfriso, A.; Facca, C.

    2013-09-01

    The growth and autoecology of two alien invasive species: Sargassum muticum and Undaria pinnatifida spreading in the Venice Lagoon were studied monthly, during one year, in two sites of different depth. S. muticum was present year-round and reached its largest size (485 cm) and maximum growth (8.33 cm d-1) at the deepest station. U. pinnatifida was present only from November to May, reaching the highest size (130 cm) in March-April in the shallow station with growth peaks of 2.32 cm d-1. The growth of both species was mainly regulated by water temperature, nutrient concentration, especially nitrogen, and water turbidity. The study highlights the different ecological role already observed for the two species: U. pinnatifida prefers eutrophic areas and is not present along the sea-coastline. Its total standing crop does not exceed 0.2 ktonnes fwt for all the Venice Lagoon. Conversely, S. muticum colonizes areas with a lower eutrophication level, such as the lagoon inlets, reaching a total lagoon standing crop of 4-6 ktonnes fwt.

  8. The direct influence of ship traffic on atmospheric PM2.5, PM10 and PAH in Venice.

    PubMed

    Contini, D; Gambaro, A; Belosi, F; De Pieri, S; Cairns, W R L; Donateo, A; Zanotto, E; Citron, M

    2011-09-01

    The direct influence of ship traffic on atmospheric levels of coarse and fine particulate matter (PM(2.5), PM(10)) and fifteen polycyclic aromatic hydrocarbons (PAHs) has been estimated in the urban area of Venice. Data analysis has been performed on results collected at three sites over the summer, when ship traffic is at a maximum. Results indicate that monitoring of the PM daily concentrations is not sufficiently detailed for the evaluation of this contribution, even though it could be useful for specific markers such as PAHs. Therefore a new methodology, based on high temporal resolution measurements coupled with wind direction information and the database of ship passages of the Harbour Authority of Venice has been developed. The sampling sites were monitored with optical detectors (DustTrack(®) and Mie pDR-1200) operating at a high temporal resolution (20s and 1s respectively) for PM(2.5) and PM(10). PAH in the particulate and gas phases were recovered from quartz fibre filters and polyurethane foam plugs using pressurised solvent extraction, the extracts were then analysed by gas chromatography- high-resolution mass spectrometry. Our results shows that the direct contribution of ships traffic to PAHs in the gas phase is 10% while the contribution to PM(2.5) and to PM(10) is from 1% up to 8%.

  9. Microbial deterioration of artistic tiles from the façade of the Grande Albergo Ausonia & Hungaria (Venice, Italy).

    PubMed

    Giacomucci, Lucia; Bertoncello, Renzo; Salvadori, Ornella; Martini, Ilaria; Favaro, Monica; Villa, Federica; Sorlini, Claudia; Cappitelli, Francesca

    2011-08-01

    The Grande Albergo Ausonia & Hungaria (Venice Lido, Italy) has an Art Nouveau polychrome ceramic coating on its façade, which was restored in 2007. Soon after the conservation treatment, many tiles of the façade decoration showed coloured alterations putatively attributed to the presence of microbial communities. To confirm the presence of the biological deposit and the stratigraphy of the Hungaria tiles, stereomicroscope, optical and environmental scanning electron microscope observations were made. The characterisation of the microbial community was performed using a PCR-DGGE approach. This study reported the first use of a culture-independent approach to identify the total community present in biodeteriorated artistic tiles. The case study examined here reveals that the coloured alterations on the tiles were mainly due to the presence of cryptoendolithic cyanobacteria. In addition, we proved that the microflora present on the tiles was generally greatly influenced by the environment of the Hungaria hotel. We found several microorganisms related to the alkaline environment, which is in the range of the tile pH, and related to the aquatic environment, the presence of the acrylic resin Paraloid B72® used during the 2007 treatment and the pollutants of the Venice lagoon.

  10. Effect of exogenous 5,8,11,14,17-eicosapentaenoic acid on cardiac anaphylaxis.

    PubMed Central

    Juan, H.; Peskar, B. A.; Simmet, T.

    1987-01-01

    The effects of infusions of eicosapentaenoic acid (EPA) (6 X 10(-8) mol min-1 and 15 X 10(-8) mol min-1) on the coronary constriction and the release of immunoreactive sulphidopeptide-leukotrienes (SP-LT), thromboxane B2(TXB2) and 6-keto-prostaglandin F1 alpha (PGF1 alpha) from perfused anaphylactic guinea-pig hearts were investigated. EPA dose-dependently inhibited the profound early coronary flow reduction after antigen injection. The less pronounced late phase of anaphylactic coronary flow reduction was, however, not significantly affected. EPA (15 X 10(-8) mol min-1) significantly shortened the average duration of antigen-induced arrhythmias. EPA dose-dependently decreased release of immunoreactive TXB2 and 6-keto-PGF1 alpha from anaphylactic guinea-pig hearts. Release of immunoreactive SP-LT was dose-dependently increased after antigen challenge in the presence of EPA. Inhibiton of the release of SP-LT by the lipoxygenase inhibitor esculetin (1 X 10(-7) mol min-1) was accompanied by a significant attenuation of flow reduction during the late phase of anaphylactic vasoconstriction. Reversed phase h.p.l.c. of perfusates from anaphylactic guinea-pig hearts revealed immunoreactivity comigrating with authentic leukotriene C4 (LTC4), LTD4, and LTE4. In perfusates from hearts treated with EPA infusions, additional immunoreactivity was detected comigrating with LTC5, LTD5 and LTE5. In addition to immunoreactivity migrating with LTB4, as observed in control heart perfusates, in perfusates from EPA-treated hearts, a second peak was observed, which coincides with the retention time described for LTB5. Exogenous LTC5 (1 X 10(-12) mol min-1 and 20 X 10(-12) mol min-1) induced dose-dependent reductions of coronary flow and was found to be a slightly weaker constrictor than LTC4, but no significant differences were observed. Coronary vasoconstriction elicited by infusion of exogenous LTC4 (20 X 10(-12) mol min-1) was dose-dependently inhibited by infusions of EPA. However

  11. The 5.8 T Cryogen-Free Gyrotron Superconducting Magnet System on HL-2A

    NASA Astrophysics Data System (ADS)

    Xia, Donghui; Huang, Mei; Zhou, Jun; Bai, Xingyu; Zheng, Tieliu; Rao, Jun; Zhuang, Ge

    2014-04-01

    A 5.8 T cryogen-free superconducting magnet (SCM) system with a warm bore hole of 160 mm in diameter, used for gyrotrons operating in the frequency range from 68 GHz to 140 GHz, is installed on the site of the HL-2A tokamak. The SCM consists of two separate solenoidal magnetic coils connected in series, a 4.2 K Gifford-McMahon (GM) refrigerator, a compressor, a coil power supply and two temperature monitors. The performance, test and preliminary experimental results of this SCM system are described in this paper. The magnetic field distribution was measured along the axis, and a dummy tube was used for adjusting the magnet system. Finally, the magnet was used for the operation of a 68 GHz/500 kW gyrotron, which is part of an electron cyclotron resonance heating (ECRH) system. With an additional auxiliary coil and after adjusting the magnet system, a maximum output power for the ECRH system of up to 400 kW was achieved.

  12. Smad1/5/8 are myogenic regulators of murine and human mesoangioblasts

    PubMed Central

    Costamagna, Domiziana; Quattrocelli, Mattia; van Tienen, Florence; Umans, Lieve; de Coo, Irineus F. M.; Zwijsen, An; Huylebroeck, Danny; Sampaolesi, Maurilio

    2016-01-01

    Mesoangioblasts (MABs) are vessel-associated stem cells that express pericyte marker genes and participate in skeletal muscle regeneration. Molecular circuits that regulate the myogenic commitment of MABs are still poorly characterized. The critical role of bone morphogenetic protein (BMP) signalling during proliferation and differentiation of adult myogenic precursors, such as satellite cells, has recently been established. We evaluated whether BMP signalling impacts on the myogenic potential of embryonic and adult MABs both in vitro and in vivo. Addition of BMP inhibited MAB myogenic differentiation, whereas interference with the interactions between BMPs and receptor complexes induced differentiation. Similarly, siRNA-mediated knockdown of Smad8 in Smad1/5-null MABs or inhibition of SMAD1/5/8 phosphorylation with Dorsomorphin (DM) also improved myogenic differentiation, demonstrating a novel role of SMAD8. Moreover, using a transgenic mouse model of Smad8 deletion, we demonstrated that the absence of SMAD8 protein improved MAB myogenic differentiation. Furthermore, once injected into α-Sarcoglycan (Sgca)-null muscles, DM-treated MABs were more efficacious to restore α-sarcoglycan (αSG) protein levels and re-establish functional muscle properties. Similarly, in acute muscle damage, DM-treated MABs displayed a better myogenic potential compared with BMP-treated and untreated cells. Finally, SMADs also control the myogenic commitment of human MABs (hMABs). BMP signalling antagonists are therefore novel candidates to improve the therapeutic effects of hMABs. PMID:26450990

  13. Proliferative response patterns of human fibroblasts after photoinjury with 4,5',8-trimethylpsoralen

    SciTech Connect

    Cohen, S.R.; Carter, D.M.; Gala, M.

    1981-01-01

    The extent of growth suppression and recovery following exposure to 4,5',8-trimethylpsoralen plus uv-A irradiation was studied in 3 diploid human fibroblast strains. Inhibition of cellular proliferation was dose-dependent within the concentration range of TMP that was tested, using a constant level of uv-A. The population generation times for all cell strains were progressively lengthened under these conditions while maximal cell densities were reduced. At 2 to 4 x 10(-7) M TMP in the presence of uv-A, there was a triphasic pattern of growth which consisted of proliferative activity during the first 24 to 36 h, followed by complete growth inhibition for variable periods of time and a recovery period of log phase proliferation that was not as vigorous as measured for untreated cells. There were also declines in the percentage of cells labeled with 3H-Tdr at various times after TMP-uv-A treatment. These measurements were essentially identical for the three fibroblast strains evaluated. In that the cells employed for these investigations were derived from embryonic pulmonary tissue, neonatal foreskin and the buttock skin of an adult male, it seems unlikely that donor age and tissue source were important variables in determining growth response patterns after TMP-uv-A exposure. Because proliferative recovery was attenuated after this photochemical injury, researchers conclude that the biologic effect(s) of TMP-uv-A extend beyond the known period of psoralen-DNA cross-link removal.

  14. Human platelets produce 14,15-oxido-5,8,11-eicosatrienoic acid from phosphatidylinositol

    SciTech Connect

    Ballou, L.R.; Lam, B.K.; Wong, P.Y.K.; Cheung, W.Y.

    1987-05-01

    Human platelets contain a soluble enzyme or enzyme system which catalyzes the formation of a compound more polar than arachidonate from 2-arachidonyl-sn-phosphatidylinositol (PtdIns). The C-value and mass spectrum of the compound appears similar to the reported values of 14,15-oxido-5,8,11-eicosatrienoic acid (EET). 2-Arachidonyl-sn-phosphatidylcholine, 2-arachidonyl-sn-phosphatidylethanolamine and arachidonic acid were not substrates for EET production. The reaction was Ca/sup 2 +/-dependent and insensitive to aspirin, mepacrin and indomethacin. EET formation was greatly reduced under nitrogen or carbon monoxide, however, exposure to atmospheric air rapidly restored EET production to a rate comparable to that under air. Further, neither NADPH nor cyanide affected EET formation, suggesting that a cytochrome P-450 system was not involved. Intact platelets prelabeled with (/sup 14/C)arachidonic acid generated at least 0.5 nmole of EET/10/sup 9/ platelets in response to thrombin; other agonists such as collagen, epinephrine, ADP or ionophore A23187 were not effective. Collectively, these data suggest that human platelets possess an enzyme system which appears to catalyze epoxidation of the arachidonyl moiety of PtdIns and its subsequent hydrolysis to yield EET.

  15. Geotechnical aspects in the epicentral region of the 2011, Mw5.8 Mineral, Virginia earthquake

    USGS Publications Warehouse

    Green, Russell A.; Lasley, Samuel; Carter, Mark W.; Munsey, Jeffrey W.; Maurer, Brett W.; Tuttle, Martitia P.

    2015-01-01

    A reconnaissance team documented the geotechnical and geological aspects in the epicentral region of the Mw (moment magnitude) 5.8 Mineral, Virginia (USA), earthquake of 23 August 2011. Tectonically and seismically induced ground deformations, evidence of liquefaction, rock slides, river bank slumps, ground subsidence, performance of earthen dams, damage to public infrastructure and lifelines, and other effects of the earthquake were documented. This moderate earthquake provided the rare opportunity to collect data to help assess current geoengineering practices in the region, as well as to assess seismic performance of the aging infrastructure in the region. Ground failures included two marginal liquefaction sites, a river bank slump, four minor rockfalls, and a ~4-m-wide, ~12-m-long, ~0.3-m-deep subsidence on a residential property. Damage to lifelines included subsidence of the approaches for a bridge and a water main break to a heavily corroded, 5-cm-diameter valve in Mineral, Virginia. Observed damage to dams, landfills, and public-use properties included a small, shallow slide in the temporary (“working”) clay cap of the county landfill, damage to two earthen dams (one in the epicentral region and one further away near Bedford, Virginia), and substantial structural damage to two public school buildings.

  16. Image features of spectral correlation function for arrhythmia classification.

    PubMed

    Khalaf, Aya F; Owis, Mohammed I; Yassine, Inas A

    2015-01-01

    Recently, computerized arrhythmia classification tools have been intensively used to aid physicians to recognize different irregular heartbeats. In this paper, we introduce arrhythmia CAD system exploiting cyclostationary signal analysis through estimation of the spectral correlation function for 5 different beat types. Two experiments were performed. Raw spectral correlation data were used as features in the first experiment while the other experiment which dealt with the spectral correlation coefficients as image included extraction of wavelet and shape features followed by fisher score for dimensionality reduction. As for the classification task, Support Vector Machine (SVM) with linear kernel was used for both experiments. The experimental results showed that both proposed approaches are superior compared to several state of the art methods. This approach achieved sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of 99.20%, 99.70%, 98.60%, 99.90% and 97.60% respectively.

  17. [Treatment of bradycardiac arrhythmias with depot-orciprenaline (author's transl)].

    PubMed

    So, C S; Volger, E

    1976-07-02

    24 patients with bradycardiac arrhythmias of various origin were treated with a new depot preparation of orciprenaline. The special galenical preparation guarantees effectiveness ofr 8-10 hours. In 21 patients (87%), therefore, one dragee morning and evening was sufficient to obtain a mean rise in frequency of 57%. The preparation had to be discontinued in 3 cases because of side effects such as increase in ventricular extrasystoles, anginal complaints and critical rise of blood pressure in hypertension. Because of its trouble-free administration in a depot form the preparation not only offers a practical advantage over the short-acting commercial preparations, but also shows a reliable efficacy. It can therefore be given under regular supervision in all forms of bradycardiac arrhythmias with stable ventricular frequency and satisfactory cardiac output.

  18. ECG Signal Analysis and Arrhythmia Detection using Wavelet Transform

    NASA Astrophysics Data System (ADS)

    Kaur, Inderbir; Rajni, Rajni; Marwaha, Anupma

    2016-12-01

    Electrocardiogram (ECG) is used to record the electrical activity of the heart. The ECG signal being non-stationary in nature, makes the analysis and interpretation of the signal very difficult. Hence accurate analysis of ECG signal with a powerful tool like discrete wavelet transform (DWT) becomes imperative. In this paper, ECG signal is denoised to remove the artifacts and analyzed using Wavelet Transform to detect the QRS complex and arrhythmia. This work is implemented in MATLAB software for MIT/BIH Arrhythmia database and yields the sensitivity of 99.85 %, positive predictivity of 99.92 % and detection error rate of 0.221 % with wavelet transform. It is also inferred that DWT outperforms principle component analysis technique in detection of ECG signal.

  19. Recent molecular insights from mutated IKS channels in cardiac arrhythmia.

    PubMed

    Dvir, Meidan; Peretz, Asher; Haitin, Yoni; Attali, Bernard

    2014-04-01

    Co-assembly of KCNQ1 with KCNE1 generates the IKS potassium current that is vital for the proper repolarization of the cardiac action potential. Mutations in either KCNQ1 or KCNE1 genes lead to life-threatening cardiac arrhythmias causing long QT syndrome, short QT syndrome, sinus bradycardia and atrial fibrillation. Findings emerging from recent studies are beginning to provide a picture of how gain-of-function and loss-of-function mutations are associated with pleiotropic cardiac phenotypes in the clinics. In this review, we discuss recent molecular insights obtained from mutations altering different structural modules of the channel complex that are essential for proper IKS function. We present the possible molecular mechanisms underlying mutations impairing the voltage sensing functions, as well as those altering the channel regulation by phosphatidylinositol-4,5-bisphosphate, calmodulin and protein kinase A. We also discuss the significance of diseased IKS channels for adequate pharmacological targeting of cardiac arrhythmias.

  20. Organical residue and agriculture like energetic reservoir: Study of economic and environmental effects in electricity production from biomass in Venice county

    SciTech Connect

    Bertoni, G.; Tromboni, S.

    1996-12-31

    The study proposes, through a technical analysis of feasibility, the individulation of a concrete solution that allows an reduction of pollution`s fonts that they burden on the Venice`s basin. This area, for his particular formation and position, contains a strongs intrinsic brittleness that progressively gets worse because of organic nature environmental pollution. This particularly forms of pollution are provoked by the agricultural activity and by other economic activity. This study examine an alternative and integrated system to utilize organic material coming from livestock farming, urban communities and various production activities that gravitates on the Venice`s logoon. This research exploits an innovative context where {open_quotes}waste implementation{close_quotes} by different methodologies is none of the most powerful means to defend the environment and to recuperate their potential energetical resources. In the present study we will try to transform the current concept of {open_quotes}eliminating and destroying{close_quotes} into a more progressive one where organic wastes take the role of raw material to be converted in energy. The loss of a high quantity of the potential energy that they present can be avoided by technologies and know-how, now available, by which we are able to transform such latent energy in alternative forms that can be directly utilized.

  1. Carbon monoxide exposure of subjects with documented cardiac arrhythmias

    SciTech Connect

    Chaitman, B.R.; Dahms, T.E.; Byers, S.; Carroll, L.W.; Younis, L.T.; Wiens, R.D. )

    1992-09-01

    The impact of low-level carbon monoxide exposure on ventricular arrhythmia frequency in patients with ischemic heart disease has not been thoroughly studied. The issue is of concern because of the potential proarrhythmic effect of carbon monoxide in patients with ischemic heart disease. We studied 30 subjects with well-documented coronary artery disease who had an average of at least 30 ventricular ectopic beats per hour over a 20-hour monitoring interval. By using appropriate inclusion and exclusion criteria, subjects were selected and enrolled in a randomized double-blind study to determine the effects of carbon monoxide exposure on ventricular arrhythmia frequency at rest, during exercise, and during ambulatory activities. The carbon monoxide exposure was designed to result in 3% or 5% carboxyhemoglobin levels, as measured by gas chromatography. The carbon monoxide exposure protocol produced target levels in 60 minutes, and the levels were maintained for an additional 90 minutes to provide adequate time to assess the impact of carbon monoxide on the frequency of ventricular ectopic beats. The data on total and repetitive ventricular arrhythmias were analyzed for seven specific time intervals: (1) two hours before carbon monoxide exposure; (2) during the two-hour carbon monoxide or air exposure; (3) during a two-hour rest period; (4) during an exercise period; (5) during an exercise recovery period; (6) six hours after carbon monoxide or air exposure; and (7) approximately 10 hours after exposure, or the remaining recording interval on the Holter monitor. There was no increase in ventricular arrhythmia frequency after carbon monoxide exposure, regardless of the level of carboxyhemoglobin or the type of activity.

  2. Amiodarone for refractory cardiac arrhythmias: 10-year study.

    PubMed Central

    Leak, D; Eydt, J N

    1986-01-01

    Over a 10-year period 130 patients with drug-resistant cardiac arrhythmias associated mainly with coronary artery disease and its complications were treated with amiodarone. The drug controlled all the tachyarrhythmias associated with the Wolff-Parkinson-White syndrome, 95% of the ventricular arrhythmias, including recurrent ventricular tachycardia and fibrillation, and 92% of the supraventricular arrhythmias. The maximum duration of therapy was 111 months and the mean 34 months. Side effects occurred in 34% of the patients, and there was one withdrawal from therapy per 15.3 patient-years of treatment. The commonest cause of withdrawal was nausea, which was significantly related (p less than 0.01) to a drug interaction with digoxin and diuretics. Reversible neurologic complications occurred in eight patients (6%), and acute myositis was recognized for the first time. Pulmonary infiltration developed in four patients (3%), who were receiving 600 mg of amiodarone per day. The rates of side effects and of withdrawal from therapy differed significantly between the patients whose maintenance doses were 600 and 200 mg/d, at 59% v. 6% (p less than 0.01) and 32% v. 0% (p less than 0.05) respectively. Thus, amiodarone is a very effective antiarrhythmic that can be administered over long periods with acceptable rates of side effects and withdrawal provided the minimal effective dose is used; 400 mg/d or less is desirable. PMID:3948063

  3. Emergency therapy of maternal and fetal arrhythmias during pregnancy

    PubMed Central

    Trappe, Hans-Joachim

    2010-01-01

    Atrial premature beats are frequently diagnosed during pregnancy (PR); supraventricular tachycardia (SVT) (atrial tachycardia, AV-nodal reentrant tachycardia, circus movement tachycardia) is less frequently diagnosed. For acute therapy, electrical cardioversion with 50–100 J is indicated in all unstable patients (pts). In stable SVT, the initial therapy includes vagal maneuvers to terminate tachycardias. For short-term management, when vagal maneuvers fail, intravenous adenosine is the first choice drug and may safely terminate the arrhythmia. Ventricular premature beats are also frequently present during PR and benign in most of the pts; however, malignant ventricular tachyarrhythmias (sustained ventricular tachycardia [VT], ventricular flutter [VFlut] or ventricular fibrillation [VF]) may occur. Electrical cardioversion is necessary in all pts who are in hemodynamically unstable situation with life-threatening ventricular tachyarrhythmias. In hemodynamically stable pts, initial therapy with ajmaline, procainamide or lidocaine is indicated. In pts with syncopal VT, VF, VFlut or aborted sudden death, an implantable cardioverter-defibrillator is indicated. In pts with symptomatic bradycardia, a pacemaker can be implanted using echocardiography at any stage of PR. The treatment of the pregnant patient with cardiac arrhythmias requires important modifications of the standard practice of arrhythmia management. The goal of therapy is to protect the patient and fetus through delivery, after which chronic or definitive therapy can be administered. PMID:20606792

  4. Small Conductance Ca2+-Activated K+ Channels and Cardiac Arrhythmias

    PubMed Central

    Zhang, Xiao-Dong; Lieu, Deborah K.; Chiamvimonvat, Nipavan

    2015-01-01

    Small conductance Ca2+-activated K+ (SK, KCa2) channels are unique in that they are gated solely by changes in intracellular Ca2+ and hence, function to integrate intracellular Ca2+ and membrane potentials on a beat-to-beat basis. Recent studies have provided evidence for the existence and functional significance of SK channels in the heart. Indeed, our knowledge of cardiac SK channels has been greatly expanded over the past decade. Interests in cardiac SK channels are further driven by recent studies suggesting the critical roles of SK channels in human atrial fibrillation, SK channel as a possible novel therapeutic target in atrial arrhythmias and up-regulation of SK channels in heart failure (HF) in animal models and human HF. However, there remain critical gaps in our knowledge. Specifically, blockade of SK channels in cardiac arrhythmias has been shown to be both anti-arrhythmic and proarrhythmic. This contemporary review will provide an overview of the literature on the role of cardiac SK channels in cardiac arrhythmias and to serve as a discussion platform for the current clinical perspectives. At the translational level, development of SK channel blockers as a new therapeutic target in the treatment of atrial fibrillation and the possible pro-arrhythmic effects merit further considerations and investigations. PMID:25956967

  5. Cardiac arrhythmias and sudden unexpected death in epilepsy (SUDEP).

    PubMed

    Velagapudi, Poonam; Turagam, Mohit; Laurence, Thomas; Kocheril, Abraham

    2012-03-01

    Sudden unexpected death in epilepsy (SUDEP) is a major clinical problem in epilepsy patients in the United States, especially those with chronic, uncontrolled epilepsy. Several pathophysiological events contributing to SUDEP include cardiac arrhythmias, respiratory dysfunction, and dysregulation of systemic or cerebral circulation. There is a significant body of literature suggesting the prominent role of cardiac arrhythmias in the pathogenesis of SUDEP. There is evidence to say that long-standing epilepsy can cause physiological and anatomical autonomic instability resulting in life-threatening arrhythmias. Tachyarrhythmias, bradyarrhythmias, and asystole are commonly seen during ictal, interictal, and postictal phase in epilepsy patients. It is unclear if these rhythm disturbances need attention as some of them may be just benign findings. Evidence regarding prolonged cardiovascular monitoring or the benefit of pacemaker/defibrillator implantation for primary or secondary prevention in epilepsy patients is limited. Awareness regarding pathophysiology, cardiac effects, and management options of SUDEP will become useful in guiding more individualized treatment in the near future. (PACE 2011; 1-8).

  6. A telemetry system for the study of spontaneous cardiac arrhythmias.

    PubMed

    Rollins, D L; Killingsworth, C R; Walcott, G P; Justice, R K; Ideker, R E; Smith, W M

    2000-07-01

    The characteristics of spontaneous cardiac arrhythmias leading to sudden cardiac death are largely unknown. To study arrhythmias in animal models, an eight-channel implantable radio telemetry system has been developed to record continuously cardiac electrograms over a period of weeks to months, with maintenance restricted to changing batteries. The inputs are connected in a unipolar manner. Each channel has a gain of fifty and is AC coupled, band limited to 0.07-260 Hz. The signals are digitized with 12 bits resolution at 1000 samples/s. The amplifiers, analog-to-digital converter, and control logic are packaged in an implantable unit. An umbilical cable is passed through the skin to an external backpack unit for power and data transmission. A custom serial interface card, a PC/104 form factor 25-MHz 80386-based single-board computer with a PCMCIA wireless local area network (WLAN) card, and battery power supply make up the backpack. Data are read into the parallel port of the computer, buffered, then transmitted over the WLAN to the laboratory network where it can be analyzed and archived. Approximately 12 h of 14,000 bytes/s data can be collected with each set of batteries. The system is suitable for continuous monitoring of animal models of spontaneous arrhythmias and sudden cardiac death.

  7. Statistical Versus Individual Forecasting Of Life-Threatening Cardiac Arrhythmias

    NASA Astrophysics Data System (ADS)

    Wessel, Niels; Meyerfeldt, Udo; Ziehmann, Christine; Schirdewan, Alexander; Kurths, Jürgen

    2002-07-01

    Ventricular tachycardia or fibrillation (VT) as fatal cardiac arrhythmias are the main factors triggering sudden cardiac death. The objective of this investigation is to find early signs of sustained VT in patients with an implanted cardioverter-defibrillator (ICD). These devices are able to safeguard patients by returning their hearts to a normal rhythm via strong defibrillatory shocks; additionally, they are able to store at least 1000 beat-to-beat intervals immediately before the onset of a life-threatening arrhythmia. We study these 1000 beat-to-beat intervals of 63 chronic heart failure ICD patients before the onset of a life-threatening arrhythmia and at a control time, i.e. without VT event. To characterize these rather short data sets, we calculate heart rate variability (HRV) parameters from time and frequency domain, from symbolic dynamics as well as the finite-time growth rates. We find that no linear parameter shows significant differences in HRV between the VT and the control time series. However, the nonlinear parameters detected a significant increase in short phases with low variability before the onset of VT (p<0.05, for time series with less than 10% ectopy). Finally, we are investigating whether these results may lead to individual predictions of VT.

  8. Rescue of mutated cardiac ion channels in inherited arrhythmia syndromes.

    PubMed

    Balijepalli, Sadguna Y; Anderson, Corey L; Lin, Eric C; January, Craig T

    2010-08-01

    Inherited arrhythmia syndromes comprise an increasingly complex group of diseases involving mutations in multiple genes encoding ion channels, ion channel accessory subunits and channel interacting proteins, and various regulatory elements. These mutations serve to disrupt normal electrophysiology in the heart, leading to increased arrhythmogenic risk and death. These diseases have added impact as they often affect young people, sometimes without warning. Although originally thought to alter ion channel function, it is now increasingly recognized that mutations may alter ion channel protein and messenger RNA processing, to reduce the number of channels reaching the surface membrane. For many of these mutations, it is also known that several interventions may restore protein processing of mutant channels to increase their surface membrane expression toward normal. In this article, we reviewed inherited arrhythmia syndromes, focusing on long QT syndrome type 2, and discuss the complex biology of ion channel trafficking and pharmacological rescue of disease-causing mutant channels. Pharmacological rescue of misprocessed mutant channel proteins, or their transcripts providing appropriate small molecule drugs can be developed, has the potential for novel clinical therapies in some patients with inherited arrhythmia syndromes.

  9. Computational approaches to understand cardiac electrophysiology and arrhythmias

    PubMed Central

    Roberts, Byron N.; Yang, Pei-Chi; Behrens, Steven B.; Moreno, Jonathan D.

    2012-01-01

    Cardiac rhythms arise from electrical activity generated by precisely timed opening and closing of ion channels in individual cardiac myocytes. These impulses spread throughout the cardiac muscle to manifest as electrical waves in the whole heart. Regularity of electrical waves is critically important since they signal the heart muscle to contract, driving the primary function of the heart to act as a pump and deliver blood to the brain and vital organs. When electrical activity goes awry during a cardiac arrhythmia, the pump does not function, the brain does not receive oxygenated blood, and death ensues. For more than 50 years, mathematically based models of cardiac electrical activity have been used to improve understanding of basic mechanisms of normal and abnormal cardiac electrical function. Computer-based modeling approaches to understand cardiac activity are uniquely helpful because they allow for distillation of complex emergent behaviors into the key contributing components underlying them. Here we review the latest advances and novel concepts in the field as they relate to understanding the complex interplay between electrical, mechanical, structural, and genetic mechanisms during arrhythmia development at the level of ion channels, cells, and tissues. We also discuss the latest computational approaches to guiding arrhythmia therapy. PMID:22886409

  10. Ventricular repolarization markers for predicting malignant arrhythmias in clinical practice

    PubMed Central

    Castro-Torres, Yaniel; Carmona-Puerta, Raimundo; Katholi, Richard E

    2015-01-01

    Malignant cardiac arrhythmias which result in sudden cardiac death may be present in individuals apparently healthy or be associated with other medical conditions. The way to predict their appearance represents a challenge for the medical community due to the tragic outcomes in most cases. In the last two decades some ventricular repolarization (VR) markers have been found to be useful to predict malignant cardiac arrhythmias in several clinical conditions. The corrected QT, QT dispersion, Tpeak-Tend, Tpeak-Tend dispersion and Tp-e/QT have been studied and implemented in clinical practice for this purpose. These markers are obtained from 12 lead surface electrocardiogram. In this review we discuss how these markers have demonstrated to be effective to predict malignant arrhythmias in medical conditions such as long and short QT syndromes, Brugada syndrome, early repolarization syndrome, acute myocardial ischemia, heart failure, hypertension, diabetes mellitus, obesity and highly trained athletes. Also the main pathophysiological mechanisms that explain the arrhythmogenic predisposition in these diseases and the basis for the VR markers are discussed. However, the same results have not been found in all conditions. Further studies are needed to reach a global consensus in order to incorporate these VR parameters in risk stratification of these patients. PMID:26301231

  11. The role of the Arrhythmia Team, an integrated, multidisciplinary approach to treatment of patients with cardiac arrhythmias: results of the European Heart Rhythm Association survey.

    PubMed

    Fumagalli, Stefano; Chen, Jian; Dobreanu, Dan; Madrid, Antonio Hernandez; Tilz, Roland; Dagres, Nikolaos

    2016-04-01

    Management of patients with cardiac arrhythmias is increasingly complex because of continuous technological advance and multifaceted clinical conditions associated with ageing of the population, the presence of co-morbidities and the need for polypharmacy. The aim of this European Heart Rhythm Association Scientific Initiatives Committee survey was to provide an insight into the role of the Arrhythmia Team, an integrated, multidisciplinary approach to management of patients with cardiac arrhythmias. Forty-eight centres from 18 European countries replied to the Web-based questionnaire. The presence of an Arrhythmia Team was reported by 44% of the respondents, whereas 17% were not familiar with this term. Apart from the electrophysiologist, health professionals who should belong to such teams, according to the majority of the respondents, include a clinical cardiologist, a nurse, a cardiac surgeon, a heart failure specialist, a geneticist, and a geriatrician. Its main activity should be dedicated to the management of patients with complex clinical conditions or refractory or inherited forms of arrhythmias. When present, the Arrhythmia Team was considered helpful by 95% of respondents; the majority of centres (79%) agreed that it should be implemented. The Arrhythmia Team seems to be connected to important expectations in the management of cardiac arrhythmias. The efficacy of such an integrated and multidisciplinary approach should be encouraged and tested in clinical practice.

  12. The role of the autonomic nervous system in arrhythmias and sudden cardiac death.

    PubMed

    Franciosi, Sonia; Perry, Frances K G; Roston, Thomas M; Armstrong, Kathryn R; Claydon, Victoria E; Sanatani, Shubhayan

    2017-03-31

    The autonomic nervous system (ANS) is complex and plays an important role in cardiac arrhythmia pathogenesis. A deeper understanding of the anatomy and development of the ANS has shed light on its involvement in cardiac arrhythmias. Alterations in levels of Sema-3a and NGF, both growth factors involved in innervation patterning during development of the ANS, leads to cardiac arrhythmias. Dysregulation of the ANS, including polymorphisms in genes involved in ANS development, have been implicated in sudden infant death syndrome. Disruptions in the sympathetic and/or parasympathetic systems of the ANS can lead to cardiac arrhythmias and can vary depending on the type of arrhythmia. Simultaneous stimulation of both the sympathetic and parasympathetic systems is thought to lead to atrial fibrillation whereas increased sympathetic stimulation is thought to lead to ventricular fibrillation or ventricular tachycardia. In inherited arrhythmia syndromes, such as Long QT and Catecholaminergic Polymorphic Ventricular Tachycardia, sympathetic system stimulation is thought to lead to ventricular tachycardia, subsequent arrhythmias, and in severe cases, cardiac death. On the other hand, arrhythmic events in Brugada Syndrome have been associated with periods of high parasympathetic tone. Increasing evidence suggests that modulation of the ANS as a therapeutic strategy in the treatment of cardiac arrhythmias is safe and effective. Further studies investigating the involvement of the ANS in arrhythmia pathogenesis and its modulation for the treatment of cardiac arrhythmias is warranted.

  13. Hurricane Irene's Impacts on the Aftershock Sequence of the 2011 Mw5.8 Virginia Earthquake

    NASA Astrophysics Data System (ADS)

    Meng, X.; Peng, Z.; Yang, H.; Allman, S.

    2013-12-01

    Recent studies have shown that typhoon could trigger shallow slow-slip events in Taiwan. However, it is unclear whether such extreme weather events could affect the occurrence of regular earthquakes as well. A good opportunity to test this hypothesis occurred in 2011 when an Mw 5.8 earthquake struck Louisa County, Virginia. This event ruptured a shallow, reverse fault. Roughly 5 days later, hurricane Irene struck the coast of Norfolk, Virginia, which is near the epicentral region of the Virginia mainshock. Because aftershocks listed in the ANSS catalog were incomplete immediately after the main shock, it is very difficult to find the genuine correlation between the seismicity rate changes and hurricane Irene. Hence, we use a recently developed waveform matched filter technique to scan through the continuous seismic data to detect small aftershocks that are previously unidentified. A mixture of 7 temporary stations from the IRIS Ramp deployment and 8 temporary stations deployed by Virginia Tech is used. The temporary stations were set up between 24 to 72 hours following the main shock around its immediate vicinity, which provides us a unique dataset recording the majority aftershock sequence of an intraplate earthquake. We us 80 aftershocks identified by Chapman [2013] as template events and scan through the continuous data from 23 August 2011 through 10 September 2011. So far, we have detected 704 events using a threshold of 12 times the median absolute deviation (MAD), which is ~25 times more than listed in the ANSS catalog. The aftershock rate generally decayed with time as predicted by the Omori's law. A statistically significant increase of seismicity rate is found when hurricane Irene passed by the epicentral region. A possible explanation is that the atmosphere pressure drop unloaded the surface, which brought the reverse faults closer to failure. However, we also identified similar fluctuations of seismicity rate changes at other times. Hence, it is still

  14. The Final Step in 5.8S rRNA Processing Is Cytoplasmic in Saccharomyces cerevisiae▿ †

    PubMed Central

    Thomson, Emma; Tollervey, David

    2010-01-01

    The 18S rRNA component of yeast (Saccharomyces cerevisiae) 40S ribosomes undergoes cytoplasmic 3′ cleavage following nuclear export, whereas exported pre-60S subunits were believed to contain only mature 5.8S and 25S rRNAs. However, in situ hybridization detected 3′-extended forms of 5.8S rRNA in the cytoplasm, which were lost when Crm1-dependent preribosome export was blocked by treatment with leptomycin B (LMB). LMB treatment rapidly blocked processing of 6S pre-rRNA to 5.8S rRNA, leading to TRAMP-dependent pre-rRNA degradation. The 6S pre-rRNA was coprecipitated with the 60S export adapter Nmd3 and cytoplasmic 60S synthesis factor Lsg1. The longer 5.8S+30 pre-rRNA (a form of 5.8S rRNA 3′ extended by ∼30 nucleotides) is processed to 6S by the nuclear exonuclease Rrp6, and nuclear pre-rRNA accumulated in the absence of Rrp6. In contrast, 6S to 5.8S processing requires the cytoplasmic exonuclease Ngl2, and cytoplasmic pre-rRNA accumulated in strains lacking Ngl2. We conclude that nuclear pre-60S particles containing the 6S pre-rRNA bind Nmd3 and Crm1 and are exported to the cytoplasm prior to final maturation by Ngl2. PMID:20008552

  15. Using high resolution data to reveal depth-dependent mechanisms that drive land subsidence: The Venice coast, Italy

    NASA Astrophysics Data System (ADS)

    Tosi, L.; Teatini, P.; Carbognin, L.; Brancolini, G.

    2009-09-01

    Recent research has provided a high-resolution map that depicts the effect of land subsidence on the Venice coastal plain of Italy. The map, which covers the decade of 1992 to 2002, was obtained by an innovative "Subsidence Integrated Monitoring System" (SIMS), which efficiently merges the different displacement measurements obtained by high precision-leveling, differential and continuous Global Positing System data (GPS), and Synthetic Aperture Radar (SAR)-based interferometry. The displacement rates exhibit significant spatial variability, ranging from a slight 1 to 2 mm/yr uplift, to a serious subsidence of more than 10 mm/yr. This paper aims to describe the many natural and anthropogenic mechanisms that drive the pattern of the ground displacement. The movement sources are presented based on their depth of occurrence. Deep causes act at depths generally greater than 400 m below m.s.l. (mean sea level), and are recognizable in the movement of the pre-Quaternary basement. Medium causes act at depths between 400 and 50 m below m.s.l., and include geological features, such as a major presence of compressible clay layers in the southern and northern portions of the study area and groundwater withdrawals, mainly in the north-eastern coastland and western mainland. Shallow causes, i.e. those occurring from a depth of 50 m up to the ground surface, are related to the architecture and geomechanical properties of the Pleistocene and Holocene deposits, which are more thick and compressible approaching the littoral belt; geochemical compaction, due to the increasing salt concentration in the clayey sediments; and oxidation of the outcropping organic soils drained by land reclamation. These two latter factors primarily involve the southern portion of the Venice coast. The building loads in newly developed areas also cause local compaction of shallow deposits. We conclude that the consolidation of Holocene deposits and anthropogenic activities (groundwater withdrawal, land

  16. Interventional and surgical treatment of cardiac arrhythmias in adults with congenital heart disease.

    PubMed

    Koyak, Zeliha; de Groot, Joris R; Mulder, Barbara J M

    2010-12-01

    Arrhythmias are a major cause of morbidity, mortality and hospital admission in adults with congenital heart disease (CHD). The etiology of arrhythmias in this population is often multifactorial and includes electrical disturbances as part of the underlying defect, surgical intervention or hemodynamic abnormalities. Despite the numerous existing arrhythmia management tools including drug therapy, pacing and ablation, management of arrhythmias in adults with CHD remains difficult and challenging. Owing to improvement in mapping and ablation techniques, ablation and arrhythmia surgery are being performed more frequently in adults with CHD. However, there is little information on the long-term results of these treatment strategies. The purpose of this article is therefore to review the available data on nonpharmacological treatment of cardiac arrhythmias in adult patients with CHD and to give an overview of the available data on the early and late outcomes of these treatment strategies.

  17. [Reply to “Did the Italian Government approve an obsolete project to save Venice?” by P.A. Pirazzoli] Obsolete? No. Necessary! Yes. The gates will save Venice

    NASA Astrophysics Data System (ADS)

    Bras, Rafael L.; Harleman, Donald R. F.; Rinaldo, Andrea; Rizzoli, Paolo

    We are confused by Paolo Antonio Pirazzoli's argument in these pages that the proposed sea gates to protect Venice from flooding by exceptional tides will not work in the event of sea-level rise. In fact, the two case studies he provides show that they would protect the city. In his examples, Pirazzoli arbitrarily adds a very large, 50-cm sea-level rise to the peak level of the October 1976 flood, which was a week-long event. A 50-cm rise in sea level corresponds to the Intergovernmental Panel on Climate Change's central value within an extraordinary range that he cites as 9-88 cm of sea-level rise at the end of 100 years. Even if one accepts this number, given the range of uncertainty, recall that it is the assumed sea-level rise at the end of 100 years.

  18. Surveillance of fetal arrhythmias in the outpatient setting: current limitations and call for action.

    PubMed

    Freire, Grace

    2015-12-01

    Surveillance of fetal arrhythmias in the outpatient setting remains limited by lack of monitoring modalities. Despite technological advances made in the field of obstetrics, existing devices are not currently suitable to monitor fetal arrhythmias. In this report, the author describes the current and developing fetal heart rate monitoring technologies including the recent introduction of hand-held Doppler monitors for outpatient surveillance of fetal arrhythmias.

  19. Catheter Ablation of Ventricular Arrhythmias Arising from the Left Ventricular Summit.

    PubMed

    Santangeli, Pasquale; Lin, David; Marchlinski, Francis E

    2016-03-01

    The left ventricular summit is a common site of origin of idiopathic ventricular arrhythmias. These arrhythmias are most commonly ablated within the coronary venous system or from other adjacent structures, such as the right ventricular and left ventricular outflow tract or coronary cusp region. When ablation from adjacent structures fails, a percutaneous epicardial approach can be considered, but is rarely successful in eliminating the arrhythmias due to proximity to major coronary vessels and/or epicardial fat.

  20. Pleiotropic Effects of Myocardial MMP-9 Inhibition to Prevent Ventricular Arrhythmia

    PubMed Central

    Weng, Ching-Hui; Chung, Fa-Po; Chen, Yao-Chang; Lin, Shien-Fong; Huang, Po-Hsun; Kuo, Terry B. J.; Hsu, Wei-Hsuan; Su, Wen-Cheng; Sung, Yen-Ling; Lin, Yenn-Jiang; Chang, Shih-Lin; Lo, Li-Wei; Yeh, Hung-I; Chen, Yi-Jen; Hong, Yi-Ren; Chen, Shih-Ann; Hu, Yu-Feng

    2016-01-01

    Observational studies have established a strong association between matrix metalloproteinase-9 (MMP-9) and ventricular arrhythmia. However, whether MMP-9 has a causal link to ventricular arrhythmia, as well as the underlying mechanism, remains unclear. Here, we investigated the mechanistic involvement of myocardial MMP-9 in the pathophysiology of ventricular arrhythmia. Increased levels of myocardial MMP-9 are linked to ventricular arrhythmia attacks after angiotensin II (Ang II) treatment. MMP-9-deficient mice were protected from ventricular arrhythmia. Increased expressions of protein kinase A (PKA) and ryanodine receptor phosphorylation at serine 2808 (pS2808) were correlated with inducible ventricular arrhythmia. MMP-9 deficiency consistently prevented PKA and pS2808 increases after Ang II treatment and reduced ventricular arrhythmia. Calcium dynamics were examined via confocal imaging in isolated murine cardiomyocytes. MMP-9 inhibition prevents calcium leakage from the sarcoplasmic reticulum and reduces arrhythmia-like irregular calcium transients via protein kinase A and ryanodine receptor phosphorylation. Human induced pluripotent stem cell-derived cardiomyocytes similarly show that MMP-9 inhibition prevents abnormal calcium leakage. Myocardial MMP-9 inhibition prevents ventricular arrhythmia through pleiotropic effects, including the modulation of calcium homeostasis and reduced calcium leakage. PMID:27966586

  1. Left ventricular function in patients with ventricular arrhythmias and aortic valve disease

    SciTech Connect

    Santinga, J.T.; Kirsh, M.M.; Brady, T.J.; Thrall, J.; Pitt, B.

    1983-02-01

    Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease.

  2. Accumulation and distribution of petroleum hydrocarbons found in mussels (Mytilus galloprovincialis) in the canals of Venice, Italy.

    PubMed

    Wetzel, Dana L; Van Vleet, Edward S

    2004-05-01

    Petroleum contamination was assessed in indigenous and transplanted mussels for three types of environments within the Venice Lagoon and its associated interior canals. Indigenous and transplanted mussels were least impacted by petroleum contamination at open-water stations, but more affected in partially-enclosed areas indicating that physical processes of tidal or wind activities can remove organic contaminants such as petroleum from these areas more effectively. Limited tidal flushing of the interior canals resulted in contaminated locations unable to support indigenous mussels. Clean mussels transplanted to these highly impacted sites accumulated the highest levels of petroleum hydrocarbons. The distribution of polycyclic aromatic hydrocarbons (PAHs) indicated mainly combustion-related activities from sources such as the nearby industrial zones and boat traffic, with some evidence of fresher petroleum inputs. Total hydrocarbons found in all mussels could be related to concentrations found in the surrounding sediments as reported in an earlier study.

  3. Characterization of hourly NOx atmospheric concentrations near the Venice International Airport with additive semi-parametric statistical models

    NASA Astrophysics Data System (ADS)

    Valotto, Gabrio; Varin, Cristiano

    2016-01-01

    An additive modeling approach is employed to provide a statistical description of hourly variation in concentrations of NOx measured in proximity of the Venice "Marco Polo" International Airport, Italy. Differently from several previous studies on airport emissions based on daily time series, the paper analyzes hourly data because variations of NOx concentrations during the day are informative about the prevailing emission source. The statistical analysis is carried out using a one-year time series. Confounder effects due to seasonality, meteorology and airport traffic volume are accounted for by suitable covariates. Four different model specifications of increasing complexity are considered. The model with the aircraft source expressed as the NOx emitted near the airport is found to have the best predictive quality. Although the aircraft source is statistically significant, the comparison of model-based predictions suggests that the relative impact of aircraft emissions to ambient NOx concentrations is limited and the road traffic is the likely dominant source near the sampling point.

  4. Source apportionment of PAHs and n-alkanes bound to PM1 collected near the Venice highway.

    PubMed

    Valotto, Gabrio; Rampazzo, Giancarlo; Gonella, Francesco; Formenton, Gianni; Ficotto, Silvia; Giraldo, Giorgia

    2017-04-01

    n-Alkanes and polycyclic aromatic hydrocarbons (PAHs) bound to atmospheric particulate matter (PM1) were investigated in a traffic site located in an urban area of Venice Province (Eastern Po Valley, Italy) during the cold season. Considering the critical situation affecting the Veneto Region concerning the atmospheric pollution and the general lack of information on PM1 composition and emission in this area, this experimental study aims at determining the source profile, their relative contributions and the dispersion of finer particles. Four sources were identified and quantified using the Positive Matrix Factorization receptor model: (1) mixed combustions related to the residential activities, (2) agricultural biomass burning in addition to the resuspension of anthropogenic and natural debris carried by the wind, (3) gasoline and (4) diesel traffic-related combustions. The role of local atmospheric circulation was also investigated to identify the pollutant sources.

  5. Farmland productivity under stress conditions: a field scale monitoring and modeling study on the Venice coastland, Italy

    NASA Astrophysics Data System (ADS)

    Manoli, Gabriele; Scudiero, Elia; Putti, Mario; Morari, Francesco; Teatini, Pietro

    2014-05-01

    The Venice coastland, Italy, is a precarious environment jeopardized by both natural and anthropogenic factors. Due to a land elevation below sea level and the presence of sandy paleo-channels, salinization of soil and shallow groundwater is posing a serious threat to the agricultural productivity of the region. In order to identify and quantify the impacts of the saltwater contamination on crop productivity an integrated monitoring and modeling approach is used. A representative 21 ha basin cultivated with maize crop has been extensively studied by soil sampling, geophysical surveys, continuous hydrological monitoring and crop yield distribution. Based on field observations a field-scale model of soil moisture dynamics coupled with plant transpiration, photosynthesis and growth has been developed and applied at the site.

  6. Subcutaneous Nerve Activity and Spontaneous Ventricular Arrhythmias in Ambulatory Dogs

    PubMed Central

    Doytchinova, Anisiia; Patel, Jheel; Zhou, Shengmei; Chen, Lan S.; Lin, Hongbo; Shen, Changyu; Everett, Thomas H; Lin, Shien-Fong; Chen, Peng-Sheng

    2014-01-01

    Background Stellate ganglion nerve activity (SGNA) is important in ventricular arrhythmogenesis. However, because thoracotomy is needed to access the stellate ganglion, it is difficult to use SGNA for risk stratification. Objective To test the hypothesis that subcutaneous nerve activity (SCNA) in canines can be used to estimate SGNA and predict ventricular arrhythmia. Methods We implanted radio transmitters to continuously monitor left stellate ganglion and subcutaneous electrical activities in 7 ambulatory dogs with myocardial infarction, complete heart block and nerve growth factor infusion to the left stellate ganglion. Results Spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) was documented in each dog. SCNA preceded a combined 61 episodes of VT and VF, 61 frequent bigeminy or couplets and 61 premature ventricular contractions within 15 s in 70%, 59% and 61% of arrhythmias, respectively. Similar incidence of 75%, 69% and 62% was noted for SGNA. Progressive increase in SCNA (48.9 (95% CI 39.3–58.5) vs. 61.8 (95% CI 45.9–77.6) vs. 75.1 (95% CI 57.5–92.7) mV-s) and SGNA (48.6 (95% CI 40.9–56.3) vs. 58.5 (95% CI 47.5–69.4) vs. 69.0 (95% CI 53.8–84.2) mV-s) integrated over 20 s intervals was demonstrated 60 s, 40 s and 20 s prior to VT/VF (p<0.05). The Pearson’s correlation coefficient for integrated SCNA and SGNA was 0.73±0.18 (p<0.0001 for all dogs, n=5). Both SCNA and SGNA exhibited circadian variation. Conclusions SCNA can be used as an estimate of SGNA to predict susceptibility to VT and VF in a canine model of ventricular arrhythmia and sudden cardiac death. PMID:25460171

  7. Role of CaMKII in cardiac arrhythmias

    PubMed Central

    Hund, Thomas J.; Mohler, Peter J.

    2014-01-01

    Protein phosphorylation is a central mechanism in vertebrates for the regulation of signaling. With regard to the cardiovascular system, phosphorylation of myocyte targets is critical for the regulation of excitation contraction coupling, metabolism, intracellular calcium regulation, mitochondrial activity, transcriptional regulation, and cytoskeletal dynamics. In fact, pathways that tune protein kinase signaling have been a mainstay for cardiovascular therapies for the past 60 years. The calcium/calmodulin-dependent protein kinase II (CaMKII) is a multifunctional serine/threonine kinase with numerous roles in human physiology. Dysfunction in CaMKII-based signaling has been linked with a host of cardiovascular phenotypes including heart failure and arrhythmia, and CaMKII levels are elevated in human and animal disease models of heart disease. While nearly a decade has been invested in targeting CaMKII for the treatment of heart failure and arrhythmia phenotypes, to date, approaches to target the molecule for antiarrhythmic benefit have been unsuccessful for reasons that are still not entirely clear, although (1) lack of compound specificity and (2) the multitude of downstream targets are likely contributing factors. This review will provide an update on current pathways regulated by CaMKII with the goal of illustrating potential upstream regulatory mechanisms and downstream targets that may be modulated for the prevention of cardiac electrical defects. While the review will cover multiple aspects of CaMKII dysfunction in cardiovascular disease, we have given special attention to the potential of CaMKII-associated late Na+ current as a novel therapeutic target for cardiac arrhythmia. PMID:25577293

  8. Distribution of Escherichia coli in a coastal lagoon (Venice, Italy): Temporal patterns, genetic diversity and the role of tidal forcing.

    PubMed

    Perini, L; Quero, G M; García, E Serrano; Luna, G M

    2015-12-15

    Despite its worldwide importance as fecal indicator in aquatic systems, little is known about the diversity of Escherichia coli in the environment and the factors driving its spatial distribution. The city of Venice (Italy), lying at the forefront of a large European lagoon, is an ideal site to study the mechanisms driving the fate of fecal bacteria, due to the huge fluxes of tourists, the city's unique architecture (causing poor efficiency of sewages treatment), and the long branching network of canals crossing the city. We summarize the results of a multi-year investigation to study the temporal dynamics of E. coli around the city, describe the population structure (by assigning isolates to their phylogenetic group) and the genotypic diversity, and explore the role of environmental factors in determining its variability. E. coli abundance in water was highly variable, ranging from being undetectable up to 10(4) Colony Forming Units (CFU) per 100 ml. Abundance did not display significant relationships with the water physico-chemical variables. The analysis of the population structure showed the presence of all known phylogroups, including extra-intestinal and potentially pathogenic ones. The genotypic diversity was very high, as likely consequence of the heterogeneous input of fecal bacteria from the city, and showed site-specific patterns. Intensive sampling during the tidal fluctuations highlighted the prominent role of tides, rather than environmental variables, as source of spatial variation, with a more evident influence in water than sediments. These results, the first providing information on the genetic properties, spatial heterogeneity and influence of tides on E. coli populations around Venice, have implications to manage the fecal pollution, and the associated waterborne disease risks, in coastal cities lying in front of lagoons and semi-enclosed basins.

  9. The VENICE Project : A GPS Network to Monitor the Deformation of Western Provence and Eastern Languedoc (Southern France)

    NASA Astrophysics Data System (ADS)

    Masson, F.; Collard, P.; Chéry, J.; Ritz, J.-F.; Doerflinger, E.; Bellier, O.; Chardon, D.; Flouzat, M.

    2003-04-01

    The present-day tectonic activity of the Western Provence - Eastern Languedoc region is demonstrated by moderate seismicity (magnitudes of 5-6.5 and recurrence periods of several tens of thousands of years for the strongest events) and sparse geological and geomorphological observations of recent deformation. It probably results from the convergence between Africa and Europe which proceeds at a rate of ~0.6 cm/year around the Western Mediterranean region. It includes E-trending fold and thrust belts (Mont-Ventoux, Luberon, Costes, Trévaresse) and NNE-trending left-lateral strike-slip faults (Moyenne Durance, Nîmes and possibly Cévennes). Regional stress field determined from inversion of earthquake focal mechanisms suggests a drastic change in the stress regime from West to East. It is extensional with an E-trending s3 axis in the western zone, along the Rhône Valley, while it is compressional in the eastern part, with an about N- to NNE-trending s1. However the present-day kinematics of the deformation in the region are still largely unknown. GPS measurements provide unique data sets for assessing crustal deformation in regions of low strain rates. In 2001, we started the implementation of a network of 15 GPS stations measured each six months during a period of 2-3 weeks (VENICE - Ventoux/Nîmes/Cévennes - semipermanent network). We are complementing this network by stations implemented around the Trevaresse ridge, reactivated by the 1909 Lambesc (M=6) earthquake. The network is designed to surround most of the faults and to be able to record co-seismic displacement in case of low magnitude earthquakes (magnitude 5-5.5). We will present the objectives of the VENICE project, the GPS networks and the first results quantifying the quality of the data by a careful study of the repeatability.

  10. Optogenetic Light Crafting Tools for the Control of Cardiac Arrhythmias.

    PubMed

    Richter, Claudia; Christoph, Jan; Lehnart, Stephan E; Luther, Stefan

    2016-01-01

    The control of spatiotemporal dynamics in biological systems is a fundamental problem in nonlinear sciences and has important applications in engineering and medicine. Optogenetic tools combined with advanced optical technologies provide unique opportunities to develop and validate novel approaches to control spatiotemporal complexity in neuronal and cardiac systems. Understanding of the mechanisms and instabilities underlying the onset, perpetuation, and control of cardiac arrhythmias will enable the development and translation of novel therapeutic approaches. Here we describe in detail the preparation and optical mapping of transgenic channelrhodopsin-2 (ChR2) mouse hearts, cardiac cell cultures, and the optical setup for photostimulation using digital light processing.

  11. Decreased respiratory sinus arrhythmia in individuals with deceptive intent.

    PubMed

    Aikins, Deane E; Martin, Daniel J; Morgan, C A

    2010-07-01

    In detecting deception, the Cognitive Load hypothesis states that lying requires more cognitive resources compared to truth telling. Further, increases in cognitive load are predicted to decrease respiratory sinus arrhythmia (RSA). We evaluated the impact of cognitive tasks and the intent to deceive on RSA in 40 male, native Arabic-speaking participants quasi-randomized into truthful (n=14) or deceptive (n=26) groups. Participants donned an ambulatory physiologic recording device and completed cognitive testing after receiving translated instructions about their role in an impending mock crime. The results show that a decrease in RSA recorded during the cognitive testing was greater in individuals who were about to commit a deceptive act.

  12. Arrhythmia ECG Noise Reduction by Ensemble Empirical Mode Decomposition

    PubMed Central

    Chang, Kang-Ming

    2010-01-01

    A novel noise filtering algorithm based on ensemble empirical mode decomposition (EEMD) is proposed to remove artifacts in electrocardiogram (ECG) traces. Three noise patterns with different power—50 Hz, EMG, and base line wander – were embedded into simulated and real ECG signals. Traditional IIR filter, Wiener filter, empirical mode decomposition (EMD) and EEMD were used to compare filtering performance. Mean square error between clean and filtered ECGs was used as filtering performance indexes. Results showed that high noise reduction is the major advantage of the EEMD based filter, especially on arrhythmia ECGs. PMID:22219702

  13. Cardiac arrhythmias produced by ultrasound and contrast agents

    NASA Astrophysics Data System (ADS)

    Rota, Claudio

    Ultrasound is used widely in medicine for both diagnostic and therapeutic applications. Ultrasound contrast agents are suspensions of gas-filled microbubbles used to enhance diagnostic imaging. Microbubble contrast agents can increase the likelihood of bioeffects of ultrasound associated with acoustic cavitation. Under certain exposure conditions, the interaction of ultrasound with cardiac tissues can produce cardiac arrhythmias. The general objective of this thesis was to develop a greater understanding of ultrasound-induced premature cardiac beats. The hypothesis guiding this work was that acoustic cavitation is the physical mechanism for the production of arrhythmias with ultrasound. This hypothesis was tested through a series of experiments with mice in vivo and theoretical investigations. Results of this research supported the acoustic cavitation hypothesis. The acoustic pressure threshold for premature beats was significantly lower with microbubble contrast agents present in the blood than without. With microbubbles, the threshold for premature beats was below the current output limits of diagnostic devices. The threshold was not significantly dependent upon contrast agent type and was not influenced by contrast agent dose over three orders of magnitude. Furthermore, the dependence of the threshold on acoustic frequency was consistent with the frequency dependence of acoustic cavitation. Experimentally determined thresholds for premature beats in vivo were in excellent agreement with theoretically estimated thresholds for inertial cavitation. A passive cavitation detector (PCD) was used to measure the acoustic emissions produced by cavitating microbubbles in vivo. A direct correlation between the amplitude of the PCD and the percentage of ultrasound pulses producing a premature beat was consistent with cavitation as a mechanism for this bioeffect. Although this thesis focused on the mechanistic understanding of ultrasound-induced arrhythmias, more persistent

  14. Anger, Emotion, and Arrhythmias: from Brain to Heart

    PubMed Central

    Taggart, Peter; Boyett, Mark R.; Logantha, Sunil Jit R. J.; Lambiase, Pier D.

    2011-01-01

    Strong emotion and mental stress are now recognized as playing a significant role in severe and fatal ventricular arrhythmias. The mechanisms, although incompletely understood, include central processing at the cortical and brain stem level, the autonomic nerves and the electrophysiology of the myocardium. Each of these is usually studied separately by investigators from different disciplines. However, many are regulatory processes which incorporate interactive feedforward and feedback mechanisms. In this review we consider the whole as an integrated interactive brain–heart system. PMID:22022314

  15. Survey and Modelling for the Bim of Basilica of San Marco in Venice

    NASA Astrophysics Data System (ADS)

    Fregonese, L.; Taffurelli, L.; Adami, A.; Chiarini, S.; Cremonesi, S.; Helder, J.; Spezzoni, A.

    2017-02-01

    The Basilica of San Marco is a singular case in the field of Cultural heritage, as it constitutes a construction site always active for the maintenance and preservation of the basilica itself. The continuous intervention of conservation, due to the particular environmental conditions of Venice and the opening to the public, together with the complexity of the building itself, imposes the need to identify an optimized management system. For this reason, in 2013 the Procurator of St. Marco Basilica commissioned the construction of a 3D model of the Basilica to be used for the creation of a BIM. The model must meet the required precision of the scale of 1:50, and should also include, in addition to the geometric description, a description of the mosaic and marble surfaces of the basilica through high resolution orthophoto which are essential for the restoration of the mosaics. The complexity of the church and the large and continuous flow of public led to work in non-optimal conditions especially for the acquisition stage. The basilica has certain peculiarities that led to some important choices, for example the use of photogrammetry instead of laser scanning technique. The same technique was preferred also by the need to realize, in addition to the geometric model, high-resolution orthophotos of marbles and mosaic surfaces. The modelling of the basilica has highlighted a number of problems related to the building features. The basilica, indeed, is the result of the juxtaposition of elements (capitals, columns) with different origin, which therefore cannot be standardized in special libraries. Moreover, especially in the extensive mosaic areas, there are not edges that characterize the architecture, but only beveled surfaces. This has resulted in a change also in the modeling paradigm with the need to identify alternative systems even for the construction of simple elements. Therefore, we decided to model using NURBS since it is the method that allows greater

  16. Anthropogenic Venice uplift by seawater pumping into a heterogeneous aquifer system

    NASA Astrophysics Data System (ADS)

    Teatini, P.; Ferronato, M.; Gambolati, G.; Baã¹, D.; Putti, M.

    2010-11-01

    In recent years, a project of anthropogenic Venice uplift caused by seawater injection into a 600-850 m deep brackish aquifer underlying the lagoon has been advanced. While an extensive data set based on marker measurements from a number of gas-producing wells of the northern Adriatic is available for a realistic evaluation of the geomechanical properties of the injected geologic formation, permeability data are very scarce and sparse throughout the area. Previous finite element (FE) predictions relying on a uniform hydraulic conductivity K as derived from pumping tests suggest that a flat uplift of the city is produced over 10 years from the inception of injection. However, it is well-known and widely recognized that in natural porous media very seldom K exhibits an even spatial distribution. In this study, a random distribution is then assumed to address the influence of a variable K on the uniformity of the city uplift. To limit the otherwise prohibitive computational burden, the study is performed relative to the pilot project designed to raise a reduced area at the margin of the lagoon. Monte Carlo groundwater flow simulations are performed using a FE discretization of the injected aquifer system based upon a hydraulic conductivity distribution characterized by a lognormal, stationary random process. The resulting pore overpressure is then implemented into a deterministic FE geomechanical model. A sensitivity analysis is performed to account for the uncertainty on the stochastic process, reflected by both the log K variance σ2 and the correlation length λ over the ranges 0.2-1.0 and 20-1000 m, respectively, which are quite plausible for normally consolidated sedimentary formations such as the Northern Adriatic basin. The cumulative distribution function (CDF) of the ground surface uplift, uz, and its horizontal gradient, ρz, are computed and used to evaluate the probability for ρz to be larger than a few significant threshold values as discussed later. It

  17. Eight years of groundwater monitoring at the building site of the MOSE system for the safeguard of Venice

    NASA Astrophysics Data System (ADS)

    Casasso, Alessandro; Sethi, Rajandrea; Di Molfetta, Antonio

    2015-04-01

    The survival of Venice is threatened by the continuous increase of frequency and intensity of tidal floods. To prevent these events, a safeguarding system known as MOSE is under construction at the inlets of the Lagoon of Venice. Four arrays of mobile barriers will be lifted in the case of exceptionally high tides (>1.10 m) to insulate the Lagoon. The prefabrication of the mobile barriers required a large construction area close to the final installation sites. Given the lack of space in the inlets of Lido and Chioggia, two basins of the future navigation locks were used for this purpose, and a system of water pumps and wells was therefore installed in each site to ensure the accessibility and safety of the construction areas. The impact of dewatering on the aquifers on the mainland in Punta Sabbioni (inlet of Lido) was monitored by means of continuous hydraulic head measurements in a network 25 piezometers, 11 screened in the phreatic aquifer and 14 in the shallowest confined aquifer. These aquifers are separated by a 5 m thick clayey aquiclude, and a 30 m thick impervious layer isolates them from the underlying confined aquifers, which were therefore not monitored. Each monitoring well was equipped with an automatic water pressure transducer and the hourly recorded hydraulic heads were compensated with the barometric pressure. The time series were compared with the natural driving forces (tides, rainfall, evapotranspiration) and the anthropogenic impact sources (dewatering pumping, slurry walls, land reclamation channels). The dynamics of seawater intrusion were also studied through monthly measurements of the vertical profiles of the electrical conductivity (EC) of groundwater. The monitoring activity was successful in assessing the impacts of the construction works. A drawdown was observed in the confined aquifer due to the dewatering pumping, with a maximum displacement of some 5 m on the mainland and an extension of some 1000 m from the dewatered basin. By

  18. 2-Aroylquinoline-5,8-diones as potent anticancer agents displaying tubulin and heat shock protein 90 (HSP90) inhibition.

    PubMed

    Nepali, Kunal; Kumar, Sunil; Huang, Hsiang-Ling; Kuo, Fei-Chiao; Lee, Cheng-Hsin; Kuo, Ching-Chuan; Yeh, Teng-Kuang; Li, Yu-Hsuan; Chang, Jang-Yang; Liou, Jing-Ping; Lee, Hsueh-Yun

    2016-01-14

    This study reports the synthesis of a series of 2-aroylquinoline-5,8-diones (11-23) on the basis of scaffold hopping. The presence of a methoxy group at C6 assists the highly regioselective incorporation with various amines, and simplifies the structural identification process. Among the synthetic compounds, 6-dimethylamino-2-(3,4,5-trimethoxybenzoyl)-quinoline-5,8-dione (12) and 7-pyrrolidin-1-yl-2-(3,4,5-trimethoxybenzoyl)-quinoline-5,8-dione (23) exhibit remarkable anti-proliferative activity against the cancer cell lines tested with mean IC50 values of 0.14 and 0.27 μM, respectively. Compound 23 showed moderate inhibitory activity against tubulin polymerization with an IC50 value of 5.9 μM. In a western blot analysis, 23 caused induction of HSP70 and degradation of Akt, revealing that it possesses HSP90 inhibitory activity.

  19. Design of 4x1 microstrip patch antenna array for 5.8 GHz ISM band applications

    NASA Astrophysics Data System (ADS)

    Valjibhai, Gohil Jayesh; Bhatia, Deepak

    2013-01-01

    This paper describes the new design of four element antenna array using corporate feed technique. The proposed antenna array is developed on the Rogers 5880 dielectric material. The antenna array works on 5.8 GHz ISM band. The industrial, scientific and medical (ISM) radio bands are radio bands (portions of the radio spectrum) reserved internationally for the use of radio frequency (RF) energy for industrial, scientific and medical purposes other than communications. The array antennas have VSWR < 1.6 from 5.725 - 5.875 GHz. The simulated return loss characteristic of the antenna array is - 39.3 dB at 5.8 GHz. The gain of the antenna array is 12.3 dB achieved. The directivity of the broadside radiation pattern is 12.7 dBi at the 5.8 GHz operating frequency. The antenna array is simulated using High frequency structure simulation software.

  20. Effects of angiotensin (5-8) microinfusions into the ventrolateral periaqueductal gray on defensive behaviors in rats.

    PubMed

    Genaro, Karina; Juliano, Maria A; Prado, Wiliam A; Brandão, Marcus L; Martins, Antônio R

    2013-11-01

    Peptides of the renin-angiotensin system modulate blood pressure and hydro-electrolyte composition. Angiotensin (Ang) receptors are localized in brain areas related to the regulation of autonomic and endocrine control and involved in sensory perception, memory process and behavioral responses. Among these areas, the ventrolateral periaqueductal gray (vlPAG) is one of the most important structures of the neuronal circuitry controlling the autonomic and behavioral components of emotional states. Although Ang II metabolism in the vlPAG forms several Ang-peptides including Ang (5-8), the role of this tetrapeptide in the organization of defensive responses has not yet been described. To address this issue, the purpose of the present study was to determine the effects of intra-vlPAG injections of Ang (5-8) (0.2, 0.4 and 0.8 nmol/0.25 μL) in rats submitted to the elevated plus-maze (EPM) test. Additionally, it was evaluated the effects of intra-vlPAG Ang (5-8) on the expression of conditioned fear, assessed by the fear-potentiated startle and contextual conditioned freezing tests. The results showed that Ang (5-8) produced an intense, dose-related reduction in the entries into and time spent in the open arms of the EPM, decreased direct exploration and increased risk assessment behaviors. Moreover, intra-vlPAG injections of Ang (5-8) before the test session promoted pro-aversive effects in the FPS and enhanced contextual freezing. Taken together, these results point out to an important anxiogenic-like action for Ang (5-8) in the mediation of defensive behaviors organized in the vlPAG.

  1. Process for manufacturing bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene

    DOEpatents

    Rasmussen, Paul George; Lawton, Richard Graham

    2014-06-03

    A process to manufacture substituted tetracyano-hexaazatricyclics with the substitutions occurring at the 9 and 10 hydrogens. The process begins with 2,3-dichloro-5,6-dicyanopyrazine, which is reacted to form the desired tetracyano-hexaazatricyclic. Different process embodiments enable different reaction paths to the desired tetracyano-hexaazatricyclic. Different tetracyano-hexaazatricyclic embodiments include bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene and bis(2-methoxyethoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracen- e.

  2. An ECG analysis interactive training system for understanding arrhythmias.

    PubMed

    Lessard, Yvon; Sinteff, Jean-Paul; Siregar, Pridi; Julen, Nathalie; Hannouche, Frédéric; Rio, Stéphane; Le Beux, Pierre

    2009-01-01

    The ECG remains a daily diagnostic tool for the detection of numerous cardiovascular diseases. Our goal was to use a computerized qualitative model (QM) of heart in order to build cases of simple arrhythmias dedicated to initial and more advanced medical teaching. The original QM is able to generate videograms of many cardiac disturbances. A Flash player is used to view ECG, synchronous Lewis diagram and chromatic 2D cardiac animation of a specific case. OAAT is a standardized 18 yes/no answers questionnaire which allows the learner to diagnose five main types of arrhythmias that can be compared with normal sinus rhythm (NSR) analysis. This new tool has been recently used by medical students during practical sessions. Based on medical reasoning learning on NSR video and upon trying to recognize an abnormal cardiac rhythm, all users can reach the 100% winning score since they can perform as many attempts as they like. We believe that unlimited case review with questionnaire answering, ECG and Lewis diagram replay and step-by-step visualization of the abnormal propagation of the cardiac impulse on the 2D heart videos are a highly efficient means to help students understand even complex arrhythmic mechanisms.

  3. Review of complementary and alternative medical treatment of arrhythmias.

    PubMed

    Brenyo, Andrew; Aktas, Mehmet K

    2014-03-01

    Complementary and alternative medical (CAM) therapies are commonly used by patients for the treatment of medical conditions spanning the full spectrum of severity and chronicity. The use of alternative remedies, both herbal and others, for conditions lacking effective medical treatment, is on the increase. Included within this categorization, arrhythmic disease-absent effective catheter-based therapy or with medical therapy limited by the toxicities of contemporary antiarrhythmic agents is frequently managed by patients with CAM therapies without their practitioner's knowledge and in the face of potential herb-drug toxicities. This study reviews 9 CAM therapies: 7 individual herbal therapies along with acupuncture and yoga that have been studied and reported as having an antiarrhythmic effect. The primary focuses are the proposed antiarrhythmic mechanism of each CAM agent along with interactions between the CAM therapies and commonly prescribed medical therapy for arrhythmia patients. We stress persistent vigilance on the part of the provider in discussing the use of herbal or other CAM agents within the arrhythmia population.

  4. Insulin tolerance test causes hypokalaemia and can provoke cardiac arrhythmias.

    PubMed

    Binder, Gerhard; Bosk, Axel; Gass, Matthias; Ranke, Michael B; Heidemann, Peter H

    2004-01-01

    We report the observation and analysis of a new adverse event during the insulin tolerance test (ITT) and propose additional safety procedures. An 8-year-old girl with growth hormone insufficiency had a cardiac arrest due to ventricular flutter when she was tested for growth hormone deficiency by the ITT. Severe hypokalaemia (K+ 2.6 mmol/l) was observed after resuscitation. Ergometry ECG revealed catecholaminergic polymorphic ventricular tachycardia, a hereditary arrhythmogenic disease. Consecutive measurements of serum potassium during ITT in 29 short children (21 boys) with growth failure revealed a mean decrease of serum potassium by 1.1 +/- 0.4 mmol/l with the nadir at 30 min after the insulin bolus. Hypokalaemia (serum potassium < 3.5 mmol/l) occurred in all but one child; severe hypokalaemia (serum potassium < 2.9 mmol/l) was measured in every third child. This observation indicates that acute hypokalaemia which is induced by insulin and catecholamine excess occurs frequently in ITT. The case shows that the combination of acute hypokalaemia and the adrenergic counterregulation in ITT is a strong trigger of cardiac arrhythmias, which can become life-threatening if the child has an arrhythmogenic disease. Therefore, we recommend ECG monitoring during ITT to enhance the detection of cardiac arrhythmias. In addition, in the case of a comatose child during ITT the determination of the glucose and potassium level as well as adequate treatment are necessary.

  5. Detection and Prevention of Cardiac Arrhythmias During Space Flight

    NASA Technical Reports Server (NTRS)

    Pillai, Dilip; Rosenbaum, David S.; Liszka, Kathy J.; York, David W.; Mackin, Michael A.; Lichter, Michael J.

    2004-01-01

    There have been reports suggesting that long-duration space flight might lead to an increased risk of potentially serious heart rhythm disturbances. If space flight does, in fact, significantly decrease cardiac electrical stability, the effects could be catastrophic, potentially leading to sudden cardiac death. It will be important to determine the mechanisms underlying this phenomenon in order to prepare for long-term manned lunar and interplanetary missions and to develop appropriate countermeasures. Electrical alternans affecting the ST segment and T-wave have been demonstrated to be common among patients at increased risk for ventricular arrhythmias. Subtle electrical alternans on the ECG may serve as a noninvasive marker of vulnerability to ventricular arrhythmias. We are studying indices of electrical instability in the heart for long term space missions by non-invasively measuring microvolt level T-wave alternans in a reduced gravity environment. In this investigation we are using volunteer subjects on the KC-135 aircraft as an initial study of the effect of electrical adaptation of the heart to microgravity. T-wave alternans will be analyzed for heart rate variability and QT restitution curve plotting will be compared for statistical significance.

  6. Postural effect on respiratory sinus arrhythmia with various respiratory frequencies.

    PubMed

    Kobayashi, H

    1996-03-01

    Heart rate variations during steady state respiration with various frequencies were studied on seven healthy male students at two different body positions. Respiration was controlled at four different frequencies (0.083, 0.100, 0.200, 0.250Hz), and the tidal volume was simultaneously controlled at 1500ml (0.083, 0.100Hz) or 1000ml (0.200, 0.250Hz). A tilting bed was used for changing body position, and the measurements were conducted at horizontal and vertical position. RSA (respiratory sinus arrhythmia) amplitude at 0.250Hz was significantly decreased at vertical position compared with horizontal position. At 0.200Hz the significant decrease could not be obtained although some tendency of decrease appeared. Contrary to these high frequencies, the amplitudes at low frequencies (0.083, 0.100Hz) were significantly increased (p < 0.01) during vertical position. This postural effect on the low frequency RSA could be regarded as a similar result on MWSA (Mayer wave relate sinus arrhythmia) which reflects sympathetic nervous activity. Furthermore, the ratio between the amplitude at 0.100Hz and that at 0.250Hz was significantly correlated with mean heart rate (n = 56, r = 0.73). From these results it was assumed that the RSA amplitude at low frequency associate a with not only parasympathetic nerves but also sympathetic nerves whereas the amplitude at high frequency was solely mediated by parasympathetic nerves.

  7. BPC 157: The counteraction of succinylcholine, hyperkalemia, and arrhythmias.

    PubMed

    Stambolija, Vasilije; Stambolija, Tamara Perleta; Holjevac, Jadranka Katancic; Murselovic, Tamara; Radonic, Jelena; Duzel, Viktor; Duplancic, Bozidar; Uzun, Sandra; Zivanovic-Posilovic, Gordana; Kolenc, Danijela; Drmic, Domagoj; Romic, Zeljko; Seiwerth, Sven; Sikiric, Predrag

    2016-06-15

    After the demonstration of its life-saving effect in severe hyperkalemia and the recovery of skeletal muscle after injury, pentadecapeptide BPC 157 has been shown to attenuate the local paralytic effect induced by succinylcholine, in addition to systemic muscle disability (and consequent muscle damage). Hyperkalemia, arrhythmias and a rise in serum enzyme values, were counteracted in rats. Assessments were made at 3 and 30min and 1, 3, 5, and 7 days after succinylcholine administration (1.0mg/kg into the right anterior tibial muscle). BPC 157 (10µg/kg, 10ng/kg) (given intraperitoneally 30min before or immediately after succinylcholine or per-orally in drinking water through 24h until succinylcholine administration) mitigated both local and systemic disturbances. BPC 157 completely eliminated hyperkalemia and arrhythmias, markedly attenuated or erradicated behavioral agitation, muscle twitches, motionless resting and completely eliminated post-succinylcholine hyperalgesia. BPC 157 immediately eliminated leg contractures and counteracted both edema and the decrease in muscle fibers in the diaphragm and injected/non-injected anterior tibial muscles. Therefore, the depolarizing neuromuscular blocker effects of succinylcholine were successfully antagonized.

  8. Arrhythmias, Sudden Cardiac Death and incapacitation of pilots

    PubMed Central

    Mantziari, L; Styliadis, C; Kourtidou-Papadeli, C; Styliadis, I

    2008-01-01

    Inflight medical emergencies occur at a rate of 20 to 100 per million passengers, with a death rate of 0.1 to 1 per million. Cardiac, neurologic, and respiratory complaints comprise the more serious emergencies, as defined by aircraft diversion or use of ground-based medical assistance. In this paper, we review changes seen in the resting electrocardiogram in normal individuals exposed to high altitude, alongside important implications for patients with heart diseases in high altitude exposures and the possible effects of high altitude to permanent cardiac pacemakers. Arrhythmias in pilots and public safety are revisited together with the guidelines of the Joint Aviation Requirements (JAR) in Europe. The situation of Military flights is also discussed. Physicians ought to become knowledgeable about the specific medical job standards for their patients when asked to render opinions regarding fitness to fly. A database must be established to obtain prospective data that defines the risk of accidents in patients who are or were being treated for arrhythmias. Current guidelines could then be updated and revised as appropriate. PMID:19050752

  9. Applying non-linear dynamics to atrial appendage flow data to understand and characterize atrial arrhythmia

    SciTech Connect

    Chandra, S.; Grimm, R.A.; Katz, R.; Thomas, J.D.

    1996-06-01

    The aim of this study was to better understand and characterize left atrial appendage flow in atrial fibrillation. Atrial fibrillation and flutter are the most common cardiac arrhythmias affecting 15% of the older population. The pulsed Doppler velocity profile data was recorded from the left atrial appendage of patients using transesophageal echocardiography. The data was analyzed using Fourier analysis and nonlinear dynamical tools. Fourier analysis showed that appendage mechanical frequency ({ital f{sub f}}) for patients in sinus rhythm was always lower (around1 Hz) than that in atrial fibrillation (5-8 Hz). Among patients with atrial fibrillation spectral power below {ital f{sub f}} was significantly different suggesting variability within this group of patients. Results that suggested the presence of nonlinear dynamics were: a) the existence of two arbitrary peak frequencies {ital f{sub 1}, f{sub 2}}, and other peak frequencies as linear combinations thereof ({ital mf{sub 1}{+-}nf{sub 2}}), and b) the similarity between the spectrum of patient data and that obtained using the Lorenz equation. Nonlinear analysis tools, including Phase plots and differential radial plots, were also generated from the velocity data using a delay of 10. In the phase plots, some patients displayed a torus-like structure, while others had a more random-like pattern. In the differential radial plots, the first set of patients (with torus-like phase plots) showed fewer values crossing an arbitrary threshold of 10 than did the second set (8 vs. 27 in one typical example). The outcome of cardioversion was different for these two set of patients. Fourier analysis helped to: differentiate between sinus rhythm and atrial fibrillation, understand the characteristics of the wide range of atrial fibrillation patients, and provide hints that atrial fibrillation could be a nonlinear process. Nonlinear dynamical tools helped to further characterize and sub-classify atrial fibrillation.

  10. Cardiac arrhythmias associated with a liquid protein diet for the treatment of obesity

    SciTech Connect

    Lantigua, R.A.; Amatruda, J.M.; Biddle, T.L.; Forbes, G.B.; Lockwood, D.H.

    1980-09-25

    Our data demonstrate that a liquid protein diet is frequently associated with potentially life-threatening arrhythmias that are not detected on routine electrocardiography. Several studies of metabolic balance failed to reveal a cause for these arrhythmias. We recommended that the use of liquid protein diets should be terminated pending further investigation of the causes and prevention of the cardiac toxicity.

  11. Sex differences in cardiac electrophysiology and clinical arrhythmias: epidemiology, therapeutics, and mechanisms.

    PubMed

    Tadros, Rafik; Ton, Anh-Tuan; Fiset, Céline; Nattel, Stanley

    2014-07-01

    Sex differences in cardiac electrophysiological properties and arrhythmias are evident in epidemiologic and investigative studies as well as in daily patient care. At the supraventricular level, women are at increased risk of sick sinus syndrome and atrioventricular (AV) node re-entrant tachycardia, whereas men manifest more AV block and accessory pathway-mediated arrhythmias. At the ventricular level, women are generally at higher risk of long QT-associated arrhythmias, whereas men are more likely to present with early repolarization, idiopathic ventricular fibrillation, and Brugada syndromes. Great advances have been made in unraveling the fundamental mechanisms underlying sex differences in ventricular arrhythmias, particularly those associated with abnormal repolarization. Conversely, the basis for male-predominant arrhythmia risk in structural heart disease and differences in supraventricular arrhythmia susceptibility are poorly understood. Beyond biological differences, arrhythmia occurrence and patient care decisions are also influenced by gender-related factors. This article reviews the current knowledge regarding the nature and underlying mechanisms of sex differences in basic cardiac electrophysiology and clinical arrhythmias.

  12. Discriminative sparse coding of ECG during ventricular arrhythmias using LC-K-SVD approach.

    PubMed

    Kalaji, I; Balasundaram, K; Umapathy, K

    2015-01-01

    Ventricular tachycardia (VT) and ventricular fibrillation (VF) are two major types of ventricular arrhythmias that results due to abnormalities in the electrical activation in the ventricles of the heart. VF is the lethal of the two arrhythmias, which may lead to sudden cardiac death. The treatment options for the two arrhythmias are different. Therefore, detection and characterization of the two arrhythmias is critical to choose appropriate therapy options. Due to the time-varying nature of the signal content during cardiac arrhythmias, modeling and extracting information from them using time and frequency localized functions would be ideal. To this effect, in this work, we perform discriminative sparse coding of the ECG during ventricular arrhythmia with hybrid time-frequency dictionaries using the recently introduced Label consistent K-SVD (LC-K-SVD) approach. Using 944 segments of ventricular arrhythmias extracted from 23 patients in the Malignant Ventricular Ectopy and Creighton University Tachy-Arrhythmia databases, an overall classification accuracy of 71.55% was attained with a hybrid dictionary of Gabor and symlet4 atoms. In comparison, for the same database and non-trained dictionary (i.e the original dictionary) the classification accuracy was found to be 62.71%. In addition, the modeling error using the trained dictionary from LC-K-SVD approach was found to be significantly lower to the one using the non-trained dictionary.

  13. Hypokalemic periodic paralysis, facial dysmorphism and ventricular arrhythmia (clinical triad of Andersen-Tawil syndrome).

    PubMed

    Thakkar, Mitesh; Biswas, T K; Desle, Hrishikesh B

    2012-11-01

    Andersen-Tawil Syndrome (ATS) is a rare potassium channel disorder, characterized by episodic weakness, ventricular arrhythmias and dysmorphic features (short stature, scoliosis, clinodactyly, hypertelorism, small or prominent low set ears, micrognathia and broad forehead). We report a case of hypokalemic periodic paralysis with dysmorphic facial features and ventricular arrhythmia resembling Andersen-Tawil syndrome.

  14. Cardiac arrhythmias in recently diagnosed hypertensive patients at first presentation: an electrocardiographic-based study.

    PubMed

    Ejim, E C; Ike, S O; Anisiuba, B C; Essien, I O; Onwubere, B J; Ikeh, V O

    2012-01-01

    Various forms of cardiac arrhythmias have been documented in hypertensive subjects, and hypertension is an important risk factor for the development of atrial and ventricular arrhythmias and sudden death. Electrocardiography at rest easily documents significant arrhythmias in patients, and this study was carried out to determine the types and frequency of arrhythmias in hypertensive subjects at first presentation in the Hypertension Clinics of the University of Nigeria Teaching Hospital (UNTH) Enugu, Nigeria. The study was hospitalbased and retrospective in nature. The resting 12lead ECG reports of 346 consecutive hypertensive subjects seen at the Hypertension clinics of the UNTH Enugu over a 14 month period were retrieved from the case files and studied. Other information obtained from the case files included the age and gender of the subjects. The mean age of the subjects was 57.3 years. Ninety-five of the subjects had arrhythmias representing 27% of the study population, out of which fifty-five were males (57.9%) and forty were females (42.1%). However 26.9% of all the male subjects had arrhythmias while 28.2% of all the females had arrhythmias. Multiple ventricular ectopics, sinus tachycardia, sinus bradycardia and atrial fibrillation were the most prevalent arrhythmias. This study showed that a significant proportion of hypertensive subjects present initially with significant rhythm disturbances.

  15. Maximizing the Effectiveness of Ablation for Arrhythmias in the Congenital Heart Patients.

    PubMed

    Arujuna, Aruna; de Bono, Joseph

    2016-07-01

    Arrhythmias are common in adults with congenital heart disease and account for a large proportion of hospitalizations. The complex anatomical heterogeneity, often in the presence of a delicate hemodynamic system, presents a significant electrophysiological challenge. This review outlines current clinical practice and advances in maximizing the effectiveness of ablation for arrhythmias in congenital heart patients.

  16. The current state of introduction of human papillomavirus vaccination into national immunisation schedules in Europe: first results of the VENICE2 2010 survey.

    PubMed

    Dorleans, F; Giambi, C; Dematte, L; Cotter, S; Stefanoff, P; Mereckiene, J; O'Flanagan, D; Lopalco, P L; D'Ancona, F; Levy-Bruhl, D

    2010-11-25

    The Venice 2 human papillomavirus vaccination survey evaluates the state of introduction of the HPV vaccination into the national immunisation schedules in the 29 participating countries. As of July 2010, 18 countries have integrated this vaccination. The vaccination policy and achievements vary among those countries regarding target age groups, delivery infrastructures and vaccination coverage reached. Financial constraints remain the major obstacle for the 11 countries who have not yet introduced the vaccination.

  17. Aconitine "challenge" test reveals a single whole-body exposure to diesel exhaust increases cardiac arrhythmia risk in hypertensive rats

    EPA Science Inventory

    Epidemiological studies demonstrate a significant association between cardiac electrical dysfunction, arrhythmias and air pollution exposure. Sensitivity to aconitine-induced arrhythmia has been used repeatedly to examine the factors that increase the risk of such cardiac electri...

  18. Aconitine Challenge Test Reveals a Single Exposure to Air Pollution Causes Increased Cardiac Arrhythmia Risk in Hypertensive Rats - Abstract

    EPA Science Inventory

    Epidemiological studies demonstrate a significant association between arrhythmias and air pollution exposure. Sensitivity to aconitine-induced arrhythmia has been used repeatedly to examine the factors that increase the risk of such cardiac electrical dysfunction. In this study, ...

  19. Mice with cardiac overexpression of PPARγ have impaired repolarization and spontaneous fatal ventricular arrhythmias (Morrow, PPARγ overexpression induces fatal arrhythmias)

    PubMed Central

    Morrow, John P.; Katchman, Alexander; Son, Ni-Huiping; Trent, Chad M.; Khan, Raffay; Shiomi, Takayuki; Huang, Haiyan; Amin, Vaibhav; Lader, Joshua M.; Vasquez, Carolina; Morley, Gregory E.; D'Armiento, Jeanine; Homma, Shunichi; Goldberg, Ira J.; Marx, Steven O.

    2011-01-01

    Background Diabetes and obesity, which confer an increased risk of sudden cardiac death, are associated with cardiomyocyte lipid accumulation and altered cardiac electrical properties, manifested by prolongation of the QRS duration and QT interval. It is difficult to distinguish the contribution of cardiomyocyte lipid accumulation versus the contribution of global metabolic defects to the increased incidence of sudden death and electrical abnormalities. Methods and Results In order to study the effects of metabolic abnormalities on arrhythmias without the complex systemic effects of diabetes and obesity, we studied cardiac-specific transgenic mice expressing PPARγ1 via the cardiac α-myosin heavy-chain promoter. The PPARγ-transgenic mice develop abnormal accumulation of intracellular lipids and die as young adults, prior to a significant reduction in systolic function. Using implantable ECG telemeters, we found that these mice have prolongation of the QRS and QT intervals, and spontaneous ventricular arrhythmias, including polymorphic ventricular tachycardia and ventricular fibrillation. Isolated cardiomyocytes demonstrated prolonged action potential duration caused by reduced expression and function of the potassium channels responsible for repolarization. Short-term exposure to pioglitazone, a PPARγ agonist, had no effect on mortality or rhythm in WT mice, but further exacerbated the arrhythmic phenotype and increased the mortality in the PPARγ TG mice. Conclusions Our findings support an important link between PPARγ activation, cardiomyocyte lipid accumulation, ion channel remodeling and increased cardiac mortality. PMID:22124376

  20. International Guidelines on Sexuality Education and Their Relevance to a Contemporary Curriculum for Children Aged 5-8 Years

    ERIC Educational Resources Information Center

    Goldman, Juliette D. G.

    2013-01-01

    This paper evaluates UNESCO's recommended sexuality educational framework for junior school students aged 5-8 years. It also compares it to an existing state-designed Health and Physical Education curriculum that includes sexual and reproductive health for the same cohort. Based on the universal values of respect and human rights, UNESCO's"…

  1. Into Adolescence: A Menu for Good Health. A Curriculum for Grades 5-8. Contemporary Health Series.

    ERIC Educational Resources Information Center

    Laing, Susan J.

    This module, oriented toward middle school students in grades 5-8, includes nine lessons designed to help students synthesize nutritional information and use it to improve their health. In lesson 1, students look at factors that influence food choices. Lesson 2 uses creative expression activities to help students learn about the role of nutrients.…

  2. Math Around the World: Grades 5-8. Teachers' Guide. Great Explorations in Math and Science (GEMS).

    ERIC Educational Resources Information Center

    Braxton, Beverly; And Others

    This document is a collection of eight games from four continents. Students use mathematics that is directly relevant to them as they take part in the games. The first five games (NIM, Kalah, Tower of Hanoi, Shongo Networks, and Magic Squares) feature presentation instructions that describe multiple-session classroom activities for grades 5-8.…

  3. Into Adolescence: Caring for Our Planet and Our Health. A Curriculum for Grades 5-8. Contemporary Health Series.

    ERIC Educational Resources Information Center

    Hunter, Lisa K.

    This module, written for middle school students in grades 5-8, is oriented toward informing students about environmental issues in relation to their own health and well-being. It is deliberately focused on a few issues that will interest young adolescents, and is not intended to be comprehensive. The six lessons stress individual action and…

  4. The relationship of arrhythmias to walking activity during mobilization after myocardial infarction.

    PubMed Central

    Roland, J. M.; Banks, D. C.; Edwards, B.; Fentem, P. H.

    1986-01-01

    The extent to which everyday walking activity is responsible for ventricular arrhythmias in the first 6 weeks after suspected myocardial infarction has been studied by simultaneous 24-hour recordings of electrocardiogram and walking activity. Forty-eight recordings from 46 patients were identified which contained couplets, ventricular tachycardia or R-on-T extrasystoles. In 24 recordings (50%) all the arrhythmias occurred whilst the patient was at rest and in a further four recordings there were fewer arrhythmias during activity than would have been expected by chance. Nineteen recordings (40%) contained arrhythmias which may have been induced by activity but in only three of these was the relationship definite. Clear evidence of arrhythmias precipitated by walking was found in only a minority of patients mobilizing after suspected myocardial infarction. PMID:3714618

  5. A Novel Automatic Detection System for ECG Arrhythmias Using Maximum Margin Clustering with Immune Evolutionary Algorithm

    PubMed Central

    Zhu, Bohui; Ding, Yongsheng; Hao, Kuangrong

    2013-01-01

    This paper presents a novel maximum margin clustering method with immune evolution (IEMMC) for automatic diagnosis of electrocardiogram (ECG) arrhythmias. This diagnostic system consists of signal processing, feature extraction, and the IEMMC algorithm for clustering of ECG arrhythmias. First, raw ECG signal is processed by an adaptive ECG filter based on wavelet transforms, and waveform of the ECG signal is detected; then, features are extracted from ECG signal to cluster different types of arrhythmias by the IEMMC algorithm. Three types of performance evaluation indicators are used to assess the effect of the IEMMC method for ECG arrhythmias, such as sensitivity, specificity, and accuracy. Compared with K-means and iterSVR algorithms, the IEMMC algorithm reflects better performance not only in clustering result but also in terms of global search ability and convergence ability, which proves its effectiveness for the detection of ECG arrhythmias. PMID:23690875

  6. [Analysis of the heart sound with arrhythmia based on nonlinear chaos theory].

    PubMed

    Ding, Xiaorong; Guo, Xingming; Zhong, Lisha; Xiao, Shouzhong

    2012-10-01

    In this paper, a new method based on the nonlinear chaos theory was proposed to study the arrhythmia with the combination of the correlation dimension and largest Lyapunov exponent, through computing and analyzing these two parameters of 30 cases normal heart sound and 30 cases with arrhythmia. The results showed that the two parameters of the heart sounds with arrhythmia were higher than those with the normal, and there was significant difference between these two kinds of heart sounds. That is probably due to the irregularity of the arrhythmia which causes the decrease of predictability, and it's more complex than the normal heart sound. Therefore, the correlation dimension and the largest Lyapunov exponent can be used to analyze the arrhythmia and for its feature extraction.

  7. Addition polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and Bis-dienes. 2: Evidence for thermal dehydration occurring in the cure process

    NASA Technical Reports Server (NTRS)

    Meador, Mary Ann B.; Olshavsky, Michael A.; Meador, Michael A.; Ahn, Myong-Ku

    1988-01-01

    Diels-Alder cycloaddition copolymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and anthracene end-capped polyimide oligomers appear, by thermogravimetric analysis (TGA), to undergo dehydration at elevated temperatures. This would produce thermally stable pentiptycene units along the polymer backbone, and render the polymers incapable of unzipping through a retro-Diels-Alder pathway. High resolution solid 13C nuclear magnetic resonance (NMR) of one formulation of the polymer system before and after heating at elevated temperatures, shows this to indeed be the case. NMR spectra of solid samples of the polymer before and after heating correlated well with those of the parent pentiptycene model compound before and after acid-catalyzed dehydration. Isothermal gravimetric analyses and viscosities of the polymer before and after heat treatment support dehydration as a mechanism for the cure reaction.

  8. Anatomical Consideration in Catheter Ablation of Idiopathic Ventricular Arrhythmias.

    PubMed

    Yamada, Takumi; Kay, G Neal

    2016-01-01

    Idiopathic ventricular arrhythmias (VAs) are ventricular tachycardias (VTs) or premature ventricular contractions (PVCs) with a mechanism that is not related to myocardial scar. The sites of successful catheter ablation of idiopathic VA origins have been progressively elucidated and include both the endocardium and, less commonly, the epicardium. Idiopathic VAs usually originate from specific anatomical structures such as the ventricular outflow tracts, aortic root, atrioventricular (AV) annuli, papillary muscles, Purkinje network and so on, and exhibit characteristic electrocardiograms based on their anatomical background. Catheter ablation of idiopathic VAs is usually safe and highly successful, but can sometimes be challenging because of the anatomical obstacles such as the coronary arteries, epicardial fat pads, intramural and epicardial origins, AV conduction system and so on. Therefore, understanding the relevant anatomy is important to achieve a safe and successful catheter ablation of idiopathic VAs. This review describes the anatomical consideration in the catheter ablation of idiopathic VAs.

  9. Flecainide: Current status and perspectives in arrhythmia management

    PubMed Central

    Andrikopoulos, George K; Pastromas, Sokratis; Tzeis, Stylianos

    2015-01-01

    Flecainide acetate is a class IC antiarrhythmic agent and its clinical efficacy has been confirmed by the results of several clinical trials. Nowadays, flecainide is recommended as one of the first line therapies for pharmacological conversion as well as maintenance of sinus rhythm in patients with atrial fibrillation and/or supraventricular tachycardias. Based on the Cardiac Arrhythmia Suppression Trial study results, flecainide is not recommended in patients with structural heart disease due to high proarrhythmic risk. Recent data support the role of flecainide in preventing ventricular tachyarrhythmias in patients with catecholaminergic polymorphic ventricular tachycardia associated both with ryanodine receptor and calsequestrin mutations. We herein review the current clinical data related to flecainide use in clinical practice and some concerns about its role in the management of patients with coronary artery disease. PMID:25717355

  10. New bipolar leads for the study of atrial arrhythmias.

    PubMed Central

    Brenes-Pereira, C

    1997-01-01

    The electrocardiography study of atrial arrhythmias has been hindered by the frequent occurrence of a "hidden". P wave in standard lead recordings. We present a modified method of surface electrocardiography that proved helpful in our prospective study of 26 consecutive patients in whom traditional surface recordings did not show the atrial mechanism. We recorded leads I, II, and III in their customary positions, except that we repositioned a pertinent limb electrode at a precordial site, in order to identify a P wave. The 4 alternative sites that we found most helpful were at the high and low parasternal positions, both to the right and to the left of the sternum. Confirmatory examples are submitted. PMID:9205986

  11. Electrophysiological assessment of amiodarone in treatment of resistant supraventricular arrhythmias.

    PubMed Central

    Rowland, E; Krikler, D M

    1980-01-01

    Oral amiodarone has been used to treat 21 patients with various supraventricular arrhythmias; 13 had Wolff-Parkinson-White syndrome, which was complicated by atrial fibrillation and re-entry atrioventricular tachycardia in four, and re-entry tachycardia alone in the other nine. The remaining eight patients had paroxysmal atrial fibrillation or flutter without pre-excitation. All were refractory to conventional treatment and had undergone intracardiac electrophysiological study. Fifteen have been controlled with amiodarone, this treatment proving most effective in atrial fibrillation or flutter with or without pre-excitation. Amiodarone was successful in only four of the nine patients with re-entry atrioventricular tachycardia. In two patients who responded well the drug had to be discontinued because of side effects. Images PMID:7426165

  12. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias.

    PubMed

    Karagueuzian, Hrayr S; Nguyen, Thao P; Qu, Zhilin; Weiss, James N

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death.

  13. Spectral analysis of sinus arrhythmia - A measure of mental effort

    NASA Technical Reports Server (NTRS)

    Vicente, Kim J.; Craig Thornton, D.; Moray, Neville

    1987-01-01

    The validity of the spectral analysis of sinus arrhythmia as a measure of mental effort was investigated using a computer simulation of a hovercraft piloted along a river as the experimental task. Strong correlation was observed between the subjective effort-ratings and the heart-rate variability (HRV) power spectrum between 0.06 and 0.14 Hz. Significant correlations were observed not only between subjects but, more importantly, within subjects as well, indicating that the spectral analysis of HRV is an accurate measure of the amount of effort being invested by a subject. Results also indicate that the intensity of effort invested by subjects cannot be inferred from the objective ratings of task difficulty or from performance.

  14. Coregulation of respiratory sinus arrhythmia in adult romantic partners.

    PubMed

    Helm, Jonathan L; Sbarra, David A; Ferrer, Emilio

    2014-06-01

    Questions surrounding physiological interdependence in romantic relationships are gaining increased attention in the research literature. One specific form of interdependence, coregulation, can be defined as the bidirectional linkage of oscillating signals within optimal bounds. Conceptual and theoretical work suggests that physiological coregulation should be instantiated in romantic couples. Although these ideas are appealing, the central tenets of most coregulatory models await empirical evaluation. In the current study, we evaluate the covariation of respiratory sinus arrhythmia (RSA) in 32 romantic couples during a series of laboratory tasks using a cross-lagged panel model. During the tasks, men's and women's RSA were associated with their partners' previous RSA responses, and this pattern was stronger for those couples with higher relationship satisfaction. The findings are discussed in terms of their implications for attachment theory, as well as the association between relationships and health.

  15. Oxidative stress, fibrosis, and early afterdepolarization-mediated cardiac arrhythmias

    PubMed Central

    Karagueuzian, Hrayr S.; Nguyen, Thao P.; Qu, Zhilin; Weiss, James N.

    2013-01-01

    Animal and clinical studies have demonstrated that oxidative stress, a common pathophysiological factor in cardiac disease, reduces repolarization reserve by enhancing the L-type calcium current, the late Na, and the Na-Ca exchanger, promoting early afterdepolarizations (EADs) that can initiate ventricular tachycardia and ventricular fibrillation (VT/VF) in structurally remodeled hearts. Increased ventricular fibrosis plays a key facilitatory role in allowing oxidative-stress induced EADs to manifest as triggered activity and VT/VF, since normal non-fibrotic hearts are resistant to arrhythmias when challenged with similar or higher levels of oxidative stress. The findings imply that antifibrotic therapy, in addition to therapies designed to suppress EAD formation at the cellular level, may be synergistic in reducing the risk of sudden cardiac death. PMID:23423152

  16. A Powerful Algorithm to aid Cardiac Arrhythmia Diagnosis.

    PubMed

    Bereksi-Reguig, F.; Hadj Slimane, Z. E.

    2000-01-01

    The Electrocardiogram (ECG), represents the electrical activity of the heart. It is characterised by a number of waves P, QRS, T which are correlated to the status of the heart activity. In this paper, the aim is to present a powerful algorithm to aid cardiac diagnosis. The approach used is based on a determinist method, that of the tree decision. However, the different waves of the ECG signal need to be identified and then measured following a signal to noise enhancement. Signal to noise enhancement is performed by a combiner linear adaptive filter whereas P, QRS, T wave identification and measurement are performed by a derivative approach. Results obtained on simulated and real ECG signals are shown to be highly, satisfactory in the aid of cardiac arrhythmia diagnosis, such as junctionnal escapes, blocks, etc.

  17. Anatomical Consideration in Catheter Ablation of Idiopathic Ventricular Arrhythmias

    PubMed Central

    Kay, G Neal

    2016-01-01

    Idiopathic ventricular arrhythmias (VAs) are ventricular tachycardias (VTs) or premature ventricular contractions (PVCs) with a mechanism that is not related to myocardial scar. The sites of successful catheter ablation of idiopathic VA origins have been progressively elucidated and include both the endocardium and, less commonly, the epicardium. Idiopathic VAs usually originate from specific anatomical structures such as the ventricular outflow tracts, aortic root, atrioventricular (AV) annuli, papillary muscles, Purkinje network and so on, and exhibit characteristic electrocardiograms based on their anatomical background. Catheter ablation of idiopathic VAs is usually safe and highly successful, but can sometimes be challenging because of the anatomical obstacles such as the coronary arteries, epicardial fat pads, intramural and epicardial origins, AV conduction system and so on. Therefore, understanding the relevant anatomy is important to achieve a safe and successful catheter ablation of idiopathic VAs. This review describes the anatomical consideration in the catheter ablation of idiopathic VAs. PMID:28116086

  18. Disruption of cardiac cholinergic neurons enhances susceptibility to ventricular arrhythmias

    PubMed Central

    Jungen, Christiane; Scherschel, Katharina; Eickholt, Christian; Kuklik, Pawel; Klatt, Niklas; Bork, Nadja; Salzbrunn, Tim; Alken, Fares; Angendohr, Stephan; Klene, Christiane; Mester, Janos; Klöcker, Nikolaj; Veldkamp, Marieke W.; Schumacher, Udo; Willems, Stephan; Nikolaev, Viacheslav O.; Meyer, Christian

    2017-01-01

    The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular electrophysiology is unclear. Here we show that cardiac cholinergic neurons modulate ventricular electrophysiology. Mechanical disruption or pharmacological blockade of parasympathetic innervation shortens ventricular refractory periods, increases the incidence of ventricular arrhythmia and decreases ventricular cAMP levels in murine hearts. Immunohistochemistry confirmed ventricular cholinergic innervation, revealing parasympathetic fibres running from the atria to the ventricles parallel to sympathetic fibres. In humans, catheter ablation of atrial fibrillation, which is accompanied by accidental parasympathetic and concomitant sympathetic denervation, raises the burden of premature ventricular complexes. In summary, our results demonstrate an influence of cardiac cholinergic neurons on the regulation of ventricular function and arrhythmogenesis. PMID:28128201

  19. Novel Calmodulin (CALM2) Mutations Associated with Congenital Arrhythmia Susceptibility

    PubMed Central

    Makita, Naomasa; Yagihara, Nobue; Crotti, Lia; Johnson, Christopher N.; Beckmann, Britt-Maria; Roh, Michelle S.; Shigemizu, Daichi; Lichtner, Peter; Ishikawa, Taisuke; Aiba, Takeshi; Homfray, Tessa; Behr, Elijah R.; Klug, Didier; Denjoy, Isabelle; Mastantuono, Elisa; Theisen, Daniel; Tsunoda, Tatsuhiko; Satake, Wataru; Toda, Tatsushi; Nakagawa, Hidewaki; Tsuji, Yukiomi; Tsuchiya, Takeshi; Yamamoto, Hirokazu; Miyamoto, Yoshihiro; Endo, Naoto; Kimura, Akinori; Ozaki, Kouichi; Motomura, Hideki; Suda, Kenji; Tanaka, Toshihiro; Schwartz, Peter J.; Meitinger, Thomas; Kääb, Stefan; Guicheney, Pascale; Shimizu, Wataru; Bhuiyan, Zahurul A.; Watanabe, Hiroshi; Chazin, Walter J.; George, Alfred L.

    2014-01-01

    Background Genetic predisposition to life-threatening cardiac arrhythmias such as in congenital long-QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT) represent treatable causes of sudden cardiac death in young adults and children. Recently, mutations in calmodulin (CALM1, CALM2) have been associated with severe forms of LQTS and CPVT, with life-threatening arrhythmias occurring very early in life. Additional mutation-positive cases are needed to discern genotype-phenotype correlations associated with calmodulin mutations. Methods and Results We employed conventional and next-generation sequencing approaches including exome analysis in genotype-negative LQTS probands. We identified five novel de novo missense mutations in CALM2 in three subjects with LQTS (p.N98S, p.N98I, p.D134H) and two subjects with clinical features of both LQTS and CPVT (p.D132E, p.Q136P). Age of onset of major symptoms (syncope or cardiac arrest) ranged from 1–9 years. Three of five probands had cardiac arrest and one of these subjects did not survive. Although all probands had LQTS, two subjects also exhibited electrocardiographic features consistent with CPVT. The clinical severity among subjects in this series was generally less than that originally reported for CALM1 and CALM2 associated with recurrent cardiac arrest during infancy. Four of five probands responded to β-blocker therapy whereas one subject with mutation p.Q136P died suddenly during exertion despite this treatment. Mutations affect conserved residues located within calcium binding loops III (p.N98S, p.N98I) or IV (p.D132E, p.D134H, p.Q136P) and caused reduced calcium binding affinity. Conclusions CALM2 mutations can be associated with LQTS and with overlapping features of LQTS and CPVT. PMID:24917665

  20. Phylogenetic relationships of the Culicomorpha inferred from 18S and 5.8S ribosomal DNA sequences. (Diptera:Nematocera).

    PubMed

    Miller, B R; Crabtree, M B; Savage, H M

    1997-05-01

    We investigated the evolutionary origins of the mosquito family Culicidae by examination of 18S and 5.8S ribosomal gene sequence divergence. Phylogenetic analyses demonstrated that within the infraorder Culicomorpha, taxa in the families Corethrellidae, Chaoboridae and Culicidae formed a monophyletic group; there was support for a sister relationship between this lineage and a representative of the Chironomidae. A chaoborid midge was the closest relative of the mosquitoes. Taxa from four genera of mosquitoes formed a monophyletic group; lack of a spacer in the 5.8S gene was unique to members of the Culicidae. A member of the genus Anopheles formed the most basal lineage among the mosquitoes analysed. Phylogenetic relationships were unresolved for representatives in the families Dixidae, Simuliidae and Ceratopogonidae.

  1. An ameliorative protocol for the quantification of purine 5',8-cyclo-2'-deoxynucleosides in oxidized DNA

    NASA Astrophysics Data System (ADS)

    Terzidis, Michael; Chatgilialoglu, Chryssostomos

    2015-07-01

    5',8-Cyclo-2'-deoxyadenosine (cdA) and 5',8-cyclo-2'-deoxyguanosine (cdG) are lesions resulting from hydroxyl radical (HO•) attack on the 5'H of the nucleoside sugar moiety and exist in both 5'R and 5'S diastereomeric forms. Increased levels of cdA and cdG are linked to Nucleotide Excision Repair mechanism deficiency and mutagenesis. Discrepancies in the damage measurements reported over recent years indicated the weakness of the actual protocols, in particular for ensuring the quantitative release of these lesions from the DNA sample and the appropriate method for their analysis. Herein we report the detailed revision leading to a cost-effective and efficient protocol for the DNA damage measurement, consisting of the nuclease benzonase and nuclease P1 enzymatic combination for DNA digestion followed by liquid chromatography isotope dilution tandem mass spectrometry analysis.

  2. Iron does not cause arrhythmias in the guinea pig model of transfusional iron overload.

    PubMed

    Kaiser, Lana; Davis, John; Patterson, Jon; Boyd, Ryan F; Olivier, N Bari; Bohart, George; Schwartz, Kenneth A

    2007-08-01

    Cardiac events, including heart failure and arrhythmias, are the leading cause of death in patients with beta thalassemia. Although cardiac arrhythmias in humans are believed to result from iron overload, excluding confounding factors in the human population is difficult. The goal of the current study was to determine whether cardiac arrhythmias occurred in the guinea pig model of secondary iron overload. Electrocardiograms were recorded by using surgically implanted telemetry devices in guinea pigs loaded intraperitoneally with iron dextran (test animals) or dextran alone (controls). Loading occurred over approximately 6 wk. Electrocardiograms were recorded for 1 wk prior to loading, throughout loading, and for approximately 4 wk after loading was complete. Cardiac and liver iron concentrations were significantly increased in the iron-loaded animals compared with controls and were in the range of those reported for humans with thalassemia. Arrhythmias were rare in both iron-loaded and control guinea pigs. No life-threatening arrhythmias were detected in either group. These data suggest that iron alone may be insufficient to cause cardiac arrhythmias in the iron-loaded guinea pig model and that arrhythmias detected in human patients with iron overload may be the result of a complex interplay of factors.

  3. Two Phase Transitions of Octa(ethylsilsesquioxane) (C2H5SIO1.5)8 (PREPRINT)

    DTIC Science & Technology

    2006-05-30

    molecular motion in the crystal slows to a rigid limit. This transition from phase I to phase II lowers the symmetry from rhombohedral to triclinic ...per asymmetric unit in phase III, which is also triclinic . Even though the transition to phase III destroys the crystal, warming it to temperatures...E-mail: pmueller@mit.edu Synopsis Crystal structures of the ethyl substituted octa-silsesquioxane (C2H5SiO1.5)8 were determined at three different

  4. Sequence analysis of the ITS region and 5.8S rDNA of Porphyra haitanensis

    NASA Astrophysics Data System (ADS)

    Li, Yanyan; Shen, Songdong; He, Lihong; Xu, Pu; Wang, Guangce

    2009-09-01

    The sequences of the ITS (internal transcribed spacer) and 5.8S rDNA of three cultivated strains of Porphyra haitanensis thalli (NB, PT and ST) were amplified, sequenced and analyzed. In addition, the phylogenic relationships of the sequences identified in this study with those of other Porphyra retrieved from GenBank were evaluated. The results are as follows: the sequences of the ITS and 5.8S rDNA were essentially identical among the three strains. The sequences of ITS1 were 331 bp to 334 bp, while those of the 5.8S rDNA were 158 bp and the sequences of ITS2 ranged from 673 bp to 681 bp. The sequences of the ITS had a high level of homology (up to 99.5%) with that of P. haitanensis (DQ662228) retrieved from GenBank, but were only approximately 50% homologous with those of other species of Porphyra. The results obtained when a phylogenetic tree was constructed coincided with the results of the homology analysis. These results suggest that the three cultivated strains of P. haitanensis evolved conservatively and that the ITS showed evolutionary consistency. However, the sequences of the ITS and 5.8S rDNA of different Porphyra species showed great variations. Therefore, the relationship of Porphyra interspecies phyletic evolution could be judged, which provides the proof for Porphyra identification study. However, proper classifications of the subspecies and the populations of Porphyra should be determined through the use of other molecular techniques to determine the genetic variability and rational phylogenetic relationships.

  5. Proposition of novel classification approach and features for improved real-time arrhythmia monitoring.

    PubMed

    Kim, Yoon Jae; Heo, Jeong; Park, Kwang Suk; Kim, Sungwan

    2016-08-01

    Arrhythmia refers to a group of conditions in which the heartbeat is irregular, fast, or slow due to abnormal electrical activity in the heart. Some types of arrhythmia such as ventricular fibrillation may result in cardiac arrest or death. Thus, arrhythmia detection becomes an important issue, and various studies have been conducted. Additionally, an arrhythmia detection algorithm for portable devices such as mobile phones has recently been developed because of increasing interest in e-health care. This paper proposes a novel classification approach and features, which are validated for improved real-time arrhythmia monitoring. The classification approach that was employed for arrhythmia detection is based on the concept of ensemble learning and the Taguchi method and has the advantage of being accurate and computationally efficient. The electrocardiography (ECG) data for arrhythmia detection was obtained from the MIT-BIH Arrhythmia Database (n=48). A novel feature, namely the heart rate variability calculated from 5s segments of ECG, which was not considered previously, was used. The novel classification approach and feature demonstrated arrhythmia detection accuracy of 89.13%. When the same data was classified using the conventional support vector machine (SVM), the obtained accuracy was 91.69%, 88.14%, and 88.74% for Gaussian, linear, and polynomial kernels, respectively. In terms of computation time, the proposed classifier was 5821.7 times faster than conventional SVM. In conclusion, the proposed classifier and feature showed performance comparable to those of previous studies, while the computational complexity and update interval were highly reduced.

  6. The electrocardiogram in the assessment of the effect of drugs on cardiac arrhythmias.

    PubMed Central

    Reid, D S

    1978-01-01

    The search for the ideal antiarrhythmic drug continues since none of the available agents offers optimum antiarrhythmic therapy. The continuing search coupled with the interest in the mechanisms of cardiac arrhythmias has led to the development of new techniques for the study of arrhythmias and antiarrhythmic drugs. In this article it is proposed to discuss the electrocardiographic methods used in the assessment of antiarrhythmic drugs. Firstly, to discuss the electrocardiogram in the assessment of the clinical electrophysiological properties of a drug and secondly, the electrocardiogram in the assessment of the value of the drug in the management of cardiac arrhythmias in man. PMID:365208

  7. Intraoperative MRI electrical noise and monitor ECG filters affect arrhythmia detection and identification.

    PubMed

    Bailey, Melissa; Kirchen, Gwynne; Bonaventura, Bridget; Rosborough, Kelly; Abdel-Rasoul, Mahmoud; Dzwonczyk, Roger

    2012-06-01

    Most electrical equipment in the modern operating room (OR) radiates electrical noise (EN) that can interfere with patient monitors. We have described the EN that an intraoperative magnetic resonance imaging (iMRI) system emits and have shown that this high-energy EN diminishes the quality of the ECG waveform during iMRI scans in our neurosurgical OR. We have also shown that the ECG signal filters in our iMRI-compatible patient monitor reduce this interference but, in the process, disturb the true morphology of the displayed waveform. This simulation study evaluates how iMRI-generated EN affects the ability of the anesthetist to detect and identify ECG arrhythmias and whether the patient monitor's ECG signal filters can improve arrhythmia recognition. Using an ECG simulator, we generated Lead II and V5 ECG signal segments that contained either no arrhythmia or one of four common cardiac arrhythmias. We filtered the ECG segments with four filters available on our iMRI-compatible monitor (Veris MR, MEDRAD Inc., Indianola, PA USA). We then digitized the segments and mixed simulated iMRI EN into the resultant tracings. With institutional approval and written informed consent, board-certified anesthesiologists reviewed the tracings, determined if an arrhythmia was present and identified the arrhythmia. We conducted the study anonymously. We reported the data as percent correct arrhythmia detection and correct arrhythmia identification. Thirty-one anesthesiologists completed the study. Overall, the participants correctly detected 79.5% (95% CI: 77.2, 81.7%) of the arrhythmias and correctly identified 62.5% (95% CI: 59.8, 65.3%) of the arrhythmias, regardless of EN presence. Although the proportions among monitor noise filters studied were not significant, the manufacturer-designated MR5 Veris MR filter optimized arrhythmia detection and arrhythmia identification for our participants, regardless if EN was present in the ECG tracings. In the neurosurgical OR, the

  8. Non-invasive cardiac mapping in clinical practice: Application to the ablation of cardiac arrhythmias.

    PubMed

    Dubois, Rémi; Shah, Ashok J; Hocini, Mélèze; Denis, Arnaud; Derval, Nicolas; Cochet, Hubert; Sacher, Frédéric; Bear, Laura; Duchateau, Josselin; Jais, Pierre; Haissaguerre, Michel

    2015-01-01

    Ten years ago, electrocardiographic imaging (ECGI) started to demonstrate its efficiency in clinical settings. The initial application to localize focal ventricular arrhythmias such as ventricular premature beats was probably the easiest to challenge and validates the concept. Our clinical experience in using this non-invasive mapping technique to identify the sources of electrical disorders and guide catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats) and ventricular pre-excitation (Wolff-Parkinson-White syndrome) is described here.

  9. Double hazards of ischemia and reperfusion arrhythmias in a patient with variant angina pectoris.

    PubMed

    Xu, Mingzhu; Yang, Xiangjun

    2015-01-01

    Variant angina pectoris, also called Prinzmetal's angina, is a syndrome caused by vasospasms of the coronary arteries. It can lead to myocardial infarction, ventricular arrhythmias, atrioventricular block and even sudden cardiac death. We report the case of a 53 year-old male patient with recurrent episodes of chest pain and arrhythmias in the course of related variant angina pectoris. It is likely that the reperfusion following myocardial ischemia was responsible for the ventricular fibrillation while the ST-segment returned to the baseline. This case showed that potential lethal arrhythmias could arise due to variant angina pectoris. It also indicated that ventricular fibrillation could be self-terminated.

  10. Environmental and traffic-related parameters affecting road dust composition: A multi-technique approach applied to Venice area (Italy)

    NASA Astrophysics Data System (ADS)

    Valotto, Gabrio; Rampazzo, Giancarlo; Visin, Flavia; Gonella, Francesco; Cattaruzza, Elti; Glisenti, Antonella; Formenton, Gianni; Tieppo, Paulo

    2015-12-01

    Road dust is a non-exhaust source of atmospheric particulate by re-suspension. It is composed of particles originating from natural sources as well as other non-exhaust source such as tire, brake and asphalt wear. The discrimination between atmospheric particles directly emitted from abrasion process and those related to re-suspension is therefore an open issue, as far as the percentage contribution of non-exhaust emissions is becoming more considerable due also to the recent policy actions and the technological upgrades in the automotive field, focused on the reduction of exhaust emissions. In this paper, road dust collected along the bridge that connects Venice (Italy) to the mainland is characterized with a multi-technique approach in order to determine its composition depending on environmental as well as traffic-related conditions. Six pollutant sources of road dust particles were identified by cluster analysis: brake, railway, tire, asphalt, soil + marine, and mixed combustions. Considering the lack of information on this matrix in this area, this study is intended to provide useful information for future identification of road dust re-suspension source in atmospheric particulate.

  11. From Point Cloud to Digital Fabrication: a Tangible Reconstruction of Ca' Venier Dei Leoni, the Guggenheim Museum in Venice

    NASA Astrophysics Data System (ADS)

    Balletti, C.; D'Agnano, F.; Guerra, F.; Vernier, P.

    2016-06-01

    The paper describes how new digital methodologies can be used within the field of Cultural Heritage, not only with the aim of documenting the actual state of an architecture but to review the past transformations it has undergone, conserving and representing these histories as well. The premise to conservation and enhancement of our Heritage is a deep study in terms of position, shape, colour, and also of the historical and artistic features. Survey methods have acquired data acquisition techniques in line with technological progress: today's electronic and IT technologies, that are the tools of modern Geomatics, allow the effective survey and representation of 3D objects, from architectural structures to sculptures or archaeological finds. Over the last few years, the methodologies of acquisition and integrated representation for 3D patrimony documentation have developed and consolidated considerably: the possibilities of the digital realm can augment the understanding and the valorisation of a monument. The specific case offered in the present paper, Ca' Venier dei Leoni, the palace where is the Guggenheim Museum in Venice, is a significant example. It suggests not only the theme of the "no longer existing", or better never built, but also the opportunity to formulate hypotheses regarding its implementation and the impact that the palace would have had in the Venetian contest.

  12. Microplastic particles in sediments of Lagoon of Venice, Italy: First observations on occurrence, spatial patterns and identification

    NASA Astrophysics Data System (ADS)

    Vianello, A.; Boldrin, A.; Guerriero, P.; Moschino, V.; Rella, R.; Sturaro, A.; Da Ros, L.

    2013-09-01

    In order to improve knowledge of the identification, distribution and abundances of microplastic particles of 1 mm or less (S-MPPs) in the coastal area of the Mediterranean region, a preliminary monitoring survey was carried out in a transitional environment along the north-eastern Italian coasts, the Lagoon of Venice. S-MPPs were evaluated in sediments collected from 10 sites chosen in shallow areas variously affected by natural conditions and anthropogenic influences (i.e., landward stations influenced by freshwater inputs, seaward areas near sea inlets, and sites influenced by the presence of aquaculture farms, industry and city centers). S-MPPs, extracted from bulk sediments by density separation, were counted and identified by Fourier-Transform Infrared Micro-spectroscopy (μFT-IR). The μFT-IR process included automatic surface chemical mapping and references to an infrared library database to identify the compositional spectra of particles. S-MPPs were recovered from all samples - a fact which emphasizes their extensive distribution throughout the Lagoon. Total abundances varied from 2175 to 672 S-MPPs kg-1 d.w., higher concentrations generally being observed in landward sites. Of the ten polymer types identified, the most abundant, accounting for more than 82% of total S-MPPs, were polyethylene and polypropylene. The most frequent size (93% of observed microplastics) was in the range 30-500 μm. Total S-MPP values were significantly correlated with the finer sediment fraction and with the metal pollution index.

  13. Hyperspectral Sensor Data Capability for Retrieving Complex Urban Land Cover in Comparison with Multispectral Data: Venice City Case Study (Italy)

    PubMed Central

    Cavalli, Rosa Maria; Fusilli, Lorenzo; Pascucci, Simone; Pignatti, Stefano; Santini, Federico

    2008-01-01

    This study aims at comparing the capability of different sensors to detect land cover materials within an historical urban center. The main objective is to evaluate the added value of hyperspectral sensors in mapping a complex urban context. In this study we used: (a) the ALI and Hyperion satellite data, (b) the LANDSAT ETM+ satellite data, (c) MIVIS airborne data and (d) the high spatial resolution IKONOS imagery as reference. The Venice city center shows a complex urban land cover and therefore was chosen for testing the spectral and spatial characteristics of different sensors in mapping the urban tissue. For this purpose, an object-oriented approach and different common classification methods were used. Moreover, spectra of the main anthropogenic surfaces (i.e. roofing and paving materials) were collected during the field campaigns conducted on the study area. They were exploited for applying band-depth and sub-pixel analyses to subsets of Hyperion and MIVIS hyperspectral imagery. The results show that satellite data with a 30m spatial resolution (ALI, LANDSAT ETM+ and HYPERION) are able to identify only the main urban land cover materials. PMID:27879879

  14. Occurrence and use of ground water in the Venice-Englewood area, Sarasota and Charlotte counties, Florida

    USGS Publications Warehouse

    Sutcliffe, Horace; Thompson, Thomas H.

    1983-01-01

    In a 75-square-mile area of coastal Sarasota and Charlotte Counties, demand for water is increasing. Groundwater, the principal source of supply, is distributed largely by public water systems. Principal water-bearing formations in descending order, include the surficial aquifer, artesian zone 1 in the Tamiami Formation, zone 2 in the upper part of the Hawthorn Formation, zone 3 in the lower part of the Hawthorn Formation and upper part of the Tampa Limestone, and zones 4 and 5 which comprise the Floridan aquifer. The surficial aquifer, except near tidewater, provides limited supplies of freshwater to wells. Artesian zone 1 is the major aquifer for public supply. It is contaminated by saline water in some areas, either as a result of inundation by storm-driven tides or by upwar leakage of mineralized water from underlying aquifers through uncased or improperly constructed wells. The city of Venice obtains some water from zone 2, but the water is brackish in much of the area. The water is suitable for irrigation in parts of the area. Except for local use of water for watering livestock and maintaining ponds, the water from zones 3, 4, and 5 is little used because of its poor quality. (USGS)

  15. Saltwater contamination in the managed low-lying farmland of the Venice coast, Italy: An assessment of vulnerability.

    PubMed

    Da Lio, Cristina; Carol, Eleonora; Kruse, Eduardo; Teatini, Pietro; Tosi, Luigi

    2015-11-15

    The original morphology and hydrogeology of many low-lying coastlands worldwide have been significantly modified over the last century through river diversion, embankment built-up, and large-scale land reclamation projects. This led to a progressive shifting of the groundwater-surficial water exchanges from naturally to anthropogenically driven. In this human-influenced hydrologic landscape, the saltwater contamination usually jeopardizes the soil productivity. In the coastland south of Venice (Italy), several well log measurements, chemical and isotope analyses have been performed over the last decade to characterize the occurrence of the salt contamination. The processing of this huge dataset highlights a permanent variously-shaped saline contamination up to 20km inland, with different conditions in relation with the various geomorphological features of the area. The results point out the important role of the land reclamation in shaping the present-day salt contamination and reveal the contribution of precipitation, river discharge, lagoon and sea water to the shallow groundwater in the various coastal sectors. Moreover, an original vulnerability map to salt contamination in relation to the farmland productivity has been developed taking into account the electrical conductivity of the upper aquifer in the worst condition, the ground elevation, and the distance from salt and fresh surface water sources. Finally, the study allows highlighting the limit of traditional investigations in monitoring saltwater contamination at the regional scale in managed Holocene coastal environments. Possible improvements are outlined.

  16. Sequential toxicity identification evaluation (TIE) for characterizing toxicity of Venice Lagoon sediments: comparison of two different approaches.

    PubMed

    Picone, Marco; Bergamin, Martina; Volpato, Elisa; Delaney, Eugenia; Turetta, Clara; Ranaldo, Martina; Capodaglio, Gabriele; Nasci, Cristina

    2009-02-01

    A toxicity identification evaluation phase-I (TIE-1) procedure was carried out on five pore water samples extracted from sediments of the Venice Lagoon previously investigated to assess both chemical contamination and toxic effects on the biota. Two different sequential TIE procedures were tested. A first sequence (TIE-1) provided for adding Na2S2O3, adding Na-EDTA, filtering, elution through a C18-SPE column and removing ammonia using the macroalgae Ulva rigida Agardh 1823, while a second procedure (TIE-2) was set up using U. rigida treatment for ammonia removal as first step, keeping unchanged the sequence of the other manipulations. Two different exposure time to the macroalgae were tested (3-h and 15-h). Sperm-cell toxicity test with the echinoid Paracentrotus lividus and embryotoxicity tests with the bivalves Mytilus galloprovincialis and Crassostrea gigas were performed on pore-water samples to assess the effect of the sequential treatments on the overall toxicity. The results confirmed that ammonia contribution to toxicity is strong in most of the samples and that metals, specially Cu, are of concern at least in three sites. The TIE-2 procedure provided more reliable results for the samples characterized by high ammonia contribution to the overall toxicity, whereas the results of TIE-1 and TIE-2 were equivalent for the samples where ammonia contribution was not prevailing. Chemical analyses and test results showed that a 3-h U. rigida exposure is suitable to remove ammonia toxicity minimizing potential metal up-take.

  17. Fetal arrhythmias: the Saint-Justine hospital experience.

    PubMed

    Fouron, Jean-Claude

    2004-12-30

    We intend to review our experience with the investigation and management of foetal arrhythmia on the basis of superior vena cava/ascending aorta (SVC/AA) Doppler flow velocity recordings. Irregular rhythms n = 307. Premature atrial and ventricular contractions were easily identified and generally self-limited in time. Sustained bradycardia n = 19. Four had sinus bradycardia, six presented with blocked atrial bigeminism, three showed 2:1, and five had a complete atrio-ventricular (AV) block. Another foetus that presented with first-degree AV block developed a Luciani-Wenckebach phenomenon 1 week later. These different types of bradycardia were all identified on SVC/AA Doppler recordings. Tachyarrhythmia n = 30. Five types of tachyarrhythmia were observed: Type I: Short ventriculo-atrial (VA) tachycardia (VA < AV), n = 11. Ten foetuses of this group presented a distinctive Doppler flow velocity pattern characterised by 1:1 AV conduction and a tall atrial wave ('a' wave) superimposed on the aortic ejection wave. They were considered to have re-entrant tachycardia through a fast-conducting AV accessory pathway; all 10 responded to digoxin therapy. The eleventh foetus with short VA tachycardia had atrial ectopic tachycardia with AV node dysfunction; he was treated successfully with sotalol. Type II: Long VA tachycardia (VA > AV): n = 8. In seven cases, an 'a' wave of normal amplitude with normal AV time interval could be clearly identified in front of the aortic ejection wave: one foetus in this group was considered to be in sinus tachycardia based on the variability of its heart rate; in another, sudden onset of tachycardia triggered by extrasystoles led to the possibility of permanent junctional reciprocating tachycardia (PJRT). The five other foetuses had atrial ectopic tachycardia. The last foetus presented with AV and VA intervals of the same duration and a heart rate of 210 beats/min; he did not respond either to digoxin or to sotalol, and was found after birth to

  18. Effect of fish oil on arrhythmias and mortality: systematic review

    PubMed Central

    León, Hernando; Shibata, Marcelo C; Sivakumaran, Soori; Dorgan, Marlene; Chatterley, Trish

    2008-01-01

    Objective To synthesise the literature on the effects of fish oil—docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)—on mortality and arrhythmias and to explore dose response and formulation effects. Design Systematic review and meta-analysis. Data sources Medline, Embase, the Cochrane Library, PubMed, CINAHL, IPA, Web of Science, Scopus, Pascal, Allied and Complementary Medicine, Academic OneFile, ProQuest Dissertations and Theses, Evidence-Based Complementary Medicine, and LILACS. Studies reviewed Randomised controlled trials of fish oil as dietary supplements in humans. Data extraction The primary outcomes of interest were the arrhythmic end points of appropriate implantable cardiac defibrillator intervention and sudden cardiac death. The secondary outcomes were all cause mortality and death from cardiac causes. Subgroup analyses included the effect of formulations of EPA and DHA on death from cardiac causes and effects of fish oil in patients with coronary artery disease or myocardial infarction. Data synthesis 12 studies totalling 32 779 patients met the inclusion criteria. A neutral effect was reported in three studies (n=1148) for appropriate implantable cardiac defibrillator intervention (odds ratio 0.90, 95% confidence interval 0.55 to 1.46) and in six studies (n=31 111) for sudden cardiac death (0.81, 0.52 to 1.25). 11 studies (n=32 439 and n=32 519) provided data on the effects of fish oil on all cause mortality (0.92, 0.82 to 1.03) and a reduction in deaths from cardiac causes (0.80, 0.69 to 0.92). The dose-response relation for DHA and EPA on reduction in deaths from cardiac causes was not significant. Conclusions Fish oil supplementation was associated with a significant reduction in deaths from cardiac causes but had no effect on arrhythmias or all cause mortality. Evidence to recommend an optimal formulation of EPA or DHA to reduce these outcomes is insufficient. Fish oils are a heterogeneous product, and the optimal formulations

  19. Brainstem sources of cardiac vagal tone and respiratory sinus arrhythmia

    PubMed Central

    Farmer, David G.S.; Dutschmann, Mathias; Paton, Julian F.R.; Pickering, Anthony E.

    2016-01-01

    Key points Cardiac vagal tone is a strong predictor of health, although its central origins are unknown.Respiratory‐linked fluctuations in cardiac vagal tone give rise to respiratory sinus arryhthmia (RSA), with maximum tone in the post‐inspiratory phase of respiration.In the present study, we investigated whether respiratory modulation of cardiac vagal tone is intrinsically linked to post‐inspiratory respiratory control using the unanaesthetized working heart‐brainstem preparation of the rat.Abolition of post‐inspiration, achieved by inhibition of the pontine Kolliker‐Fuse nucleus, removed post‐inspiratory peaks in efferent cardiac vagal activity and suppressed RSA, whereas substantial cardiac vagal tone persisted. After transection of the caudal pons, part of the remaining tone was removed by inhibition of nucleus of the solitary tract.We conclude that cardiac vagal tone depends upon at least 3 sites of the pontomedullary brainstem and that a significant proportion arises independently of RSA. Abstract Cardiac vagal tone is a strong predictor of health, although its central origins are unknown. The rat working heart‐brainstem preparation shows strong cardiac vagal tone and pronounced respiratory sinus arrhythmia. In this preparation, recordings from the cut left cardiac vagal branch showed efferent activity that peaked in post‐inspiration, ∼0.5 s before the cyclic minimum in heart rate (HR). We hypothesized that respiratory modulation of cardiac vagal tone and HR is intrinsically linked to the generation of post‐inspiration. Neurons in the pontine Kölliker‐Fuse nucleus (KF) were inhibited with bilateral microinjections of isoguvacine (50–70 nl, 10 mm) to remove the post‐inspiratory phase of respiration. This also abolished the post‐inspiratory peak of cardiac vagal discharge (and cyclical HR modulation), although a substantial level of activity remained. In separate preparations with intact cardiac vagal branches but

  20. Dipyridamole-thallium tests are predictive of severe cardiac arrhythmias in patients with left ventricular hypertrophy

    SciTech Connect

    Saragoca, M.A.; Canziani, M.E.; Gil, M.A.; Castiglioni, M.L.; Cassiolato, J.L.; Barbieri, A.; Lima, V.C.; Draibe, S.A.; Martinez, E.E. )

    1991-01-01

    In a population of patients with chronic renal failure (CRF) and a high prevalence of left ventricular hypertrophy (LVH) undergoing chronic hemodialysis, the authors investigated the association between the results of dipyridamole-thallium tests (DTTs) and the occurrence of ventricular arrhythmias. They observed a positive significant association between positive DTTs and the occurrence of severe forms of ventricular arrhythmias. A significant association was also observed between the presence of severe LVH and the occurrence of severe ventricular arrhythmias. However, no association was found between the presence of LVH and the positivity of the DTT. As most of their patients with positive DTTs had unimpaired coronary circulations, they conclude that positive DTTs, although falsely indicative of impaired myocardial blood supply, does have an important clinical relevance, indicating increased risk of morbidity (and, possibly, mortality) due to ventricular arrhythmias in a population of CRF patients submitted to chronic renal function replacement program.

  1. Induced pluripotent stem cell-derived cardiomyocytes: boutique science or valuable arrhythmia model?

    PubMed

    Knollmann, Björn C

    2013-03-15

    This article reviews the strengths and limitations of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) as models of cardiac arrhythmias. Specifically, the article attempts to answer the following questions: Which clinical arrhythmias can be modeled by iPSC-CM? How well can iPSC-CM model adult ventricular myocytes? What are the strengths and limitations of published iPSC-CM arrhythmia models? What new mechanistic insight has been gained? What is the evidence that would support using iPSC-CM to personalize antiarrhythmic drug therapy? The review also discusses the pros and cons of using the iPSC-CM technology for modeling specific genetic arrhythmia disorders, such as long QT syndrome, Brugada Syndrome, or Catecholaminergic Polymorphic Ventricular Tachycardia.

  2. Extracellular photosensitization reaction progress and effect on myocardial cell necrosis for arrhythmia treatment application

    NASA Astrophysics Data System (ADS)

    Ogawa, Emiyu; Takahashi, Mei; Ito, Arisa; Arai, Tsunenori

    2013-06-01

    We investigated detailed extracellular photosensitization reaction effect on rat myocardial cells and the photosensitization reaction progress in a well to study a new application of photodynamic therapy for arrhythmia therapy.

  3. Combination of opium smoking and hypercholesterolemia augments susceptibility for lethal cardiac arrhythmia and atherogenesis in rabbit.

    PubMed

    Najafipour, Hamid; Joukar, Siyavash

    2012-09-01

    Opium consumption is increasing in some eastern societies, where it is grown. We investigated the effect of opium smoking on plasma atherogenic index and incidence of lethal cardiac arrhythmia, i.e. ventricular tachycardia (VT) and ventricular fibrillation (VF) in rabbits. Animals were divided into two-, normo- and hyper-cholesterolemic main groups fed with normal or high cholesterol diet prior and during short-term and long-term exposure to opium smoke. Then, isoproterenol (3mg/kg, i.p.) was injected to induce cardiac ischemia and animals were followed for 3h for counting of lethal arrhythmia incidence. Long-term opium smoking significantly increased the plasma atherogenic index. In ischemic hearts, opium smoking along with hypercholesterolemia significantly enhanced the incidence of fatal arrhythmia. This vulnerability was not mediated by changes in QT interval. These data suggest that opium smoking, especially in hypercholesterolemic conditions, can be a predisposing factor for atherogenesis and lethal arrhythmia.

  4. [Magnesium deficiency and therapy in cardiac arrhythmias: recommendations of the German Society for Magnesium Research].

    PubMed

    Vierling, W; Liebscher, D-H; Micke, O; von Ehrlich, B; Kisters, K

    2013-05-01

    Aim of the recommendations of the German Society for Magnesium Research: Recognition and compensation of magnesium deficiency in patients with risk factors for cardiac arrhythmias or manifest rhythm disturbances. Prevention of arrhythmias by administration of magnesium. Therapeutic administration of magnesium in patients with arrhythmias with and without magnesium deficiency. The current state of knowledge claims for considering the status of magnesium and the possibility of a therapeutic intervention with magnesium within the concept of the treatment of cardiovascular diseases. The use of magnesium as single agent or as an adjunct to other therapeutic actions in the prevention and therapy of cardiac arrhythmias can be effective and, in case of oral administration, very safe. In case of parenteral administration, it is important to use adequate doses, monitor cardiovascular and neuromuscular parameters and to consider contraindications.

  5. Effect of Cardiac Arrhythmia Simulation on Nursing Students' Knowledge Acquisition and Retention.

    PubMed

    Tubaishat, Ahmad; Tawalbeh, Loai I

    2015-09-01

    The realistic and practical environment that simulation provides is an extremely useful part of the teaching process. Simulation is widely used in health and nursing education today. This study aims to evaluate the effect of simulation-based teaching on the acquisition and retention of arrhythmia-related knowledge among nursing students. A randomized controlled design involving a pretest-posttest was used. Nursing students were allocated randomly either to the experimental group (n = 47), who attended simulation scenarios on cardiac arrhythmia, or to the control group (n = 44) who received a traditional lecture on the same topic. A paired t test showed that the mean knowledge score at the posttest was significantly higher than at the pretest for both groups. However, participants in the experimental group demonstrated significantly increased knowledge of cardiac arrhythmia in the first and the second posttest compared with those in the control group. Thus, simulation is superior and significantly improves students' arrhythmia knowledge.

  6. Updates from the British Association of Dermatologists 85th annual meeting, 5-8 July 2005, Glasgow, U.K.

    PubMed

    Eedy, D J; English, J S C; Coulson, I H

    2006-06-01

    The conference highlighted the progress made in understanding recent biological, epidemiological and therapeutic advances in dermatology. Here we provide a synopsis of the main research and clinical findings presented at the meeting of the British Association of Dermatologists (BAD) held during 5-8 July 2005, in Glasgow, U.K., drawing attention to the most important advances and summaries. The BAD meeting was held at the Scottish Exhibition and Conference Centre, Glasgow (Fig. 1). The annual dinner was held in the wonderful setting of Stirling Castle, with Dr Robin Graham-Brown as host.

  7. Nucleotide sequence of the internal transcribed spacers and 5.8S region of ribosomal DNA in Pinus pinea L.

    PubMed

    Marrocco, R; Gelati, M T; Maggini, F

    1996-01-01

    The nucleotide sequence of the first internal transcribed spacer (ITS1) belonging to different ribosomal RNA genes from Pinus pinea are reported. The analyzed ITS1 can be distinguished on the basis of their length, being one 2631 bp and the other 271 bp long. Nucleotide comparison of these regions did not show appreciable sequence homology. The larger ITS1 contains five tandem arranged subrepeats with size ranging between 219 bp and 237 bp. The nucleotide sequence of the 5.8S and the ITS2 regions belonging to the larger ribosomal RNA gene are also reported.

  8. Intracavity-pumped, cascaded AgGaSe₂ optical parametric oscillator tunable from 5.8 to 18 µm.

    PubMed

    Boyko, Andrey A; Marchev, Georgi M; Petrov, Valentin; Pasiskevicius, Valdas; Kolker, Dmitry B; Zukauskas, Andrius; Kostyukova, Nadezhda Y

    2015-12-28

    A AgGaSe2 nonlinear crystal placed in a coupled cavity is intracavity pumped by the ~1.85-µm signal pulses of a 1.064-µm pumped Rb:PPKTP doubly-resonant optical parametric oscillator (OPO) operating at a repetition rate of 100 Hz. Using two samples cut for type-I and II phase-matching, the overall idler tunability of the singly-resonant AgGeSe2 OPO covers an unprecedented spectral range from 5.8 to ~18 µm in the mid-IR.

  9. Stabilisation of medically refractory ventricular arrhythmia by intra-aortic balloon counterpulsation

    PubMed Central

    Fotopoulos, G; Mason, M; Walker, S; Jepson, N; Patel, D; Mitchell, A; Ilsley, C; Paul, V

    1999-01-01

    OBJECTIVE—To review the efficacy of intra-aortic balloon counterpulsation (IABCP) in medically refractory ventricular arrhythmia.
DESIGN—Retrospective analysis of the outcome of patients with ventricular arrhythmia treated with IABCP after transfer between 1992 and 1997.
SETTING—Tertiary cardiac referral centre.
PATIENTS—21 patients (mean age 58 years) who underwent IABCP for control of ventricular arrhythmia. All had significant left ventricular impairment (mean ejection fraction 28.6%); 18 had coronary artery disease.
RESULTS—Before IABCP, 10 patients had incessant monomorphic ventricular tachycardia and 11 had paroxysmal ventricular tachycardia and/or ventricular fibrillation (VT/VF). IABCP resulted in suppression of ventricular arrhythmia in 18 patients, of whom 13 were weaned from IABCP. After stabilisation of ventricular arrhythmia, 10 patients were maintained on medical treatment alone and one underwent endocardial resection. IABCP was maintained until cardiac transplantation in five patients. One patient had a fatal arrest before discharge and one died from progressive heart failure. IABCP failed to control ventricular arrhythmia in three patients and was subsequently discontinued. A cardiac assist device was employed in one of these until cardiac transplantation; the other two were eventually stabilised on medical treatment. Nineteen patients were discharged from hospital. Overall survival was 95% at mean follow up of 25.7 months.
CONCLUSIONS—IABCP can be an effective means of controlling refractory ventricular arrhythmia, allowing time for the institution of more definitive treatment.


Keywords: ventricular arrhythmia; intra-aortic balloon counterpulsation PMID:10377318

  10. Inhibition of Angiotensin-II Production Increases Susceptibility to Acute Ischemia/Reperfusion Arrhythmia

    PubMed Central

    Taskin, Eylem; Tuncer, Kadir Ali; Guven, Celal; Kaya, Salih Tunc; Dursun, Nurcan

    2016-01-01

    Background Myocardial ischemia and reperfusion lead to impairment of electrolyte balance and, eventually, lethal arrhythmias. The aim of this study was to investigate the effects of pharmacological inhibition of angiotensin-II (Ang-II) production on heart tissue with ischemia-reperfusion damage, arrhythmia, and oxidative stress. Material/Methods Rats were divided into 4 groups: only ischemia/reperfusion (MI/R), captopril (CAP), aliskiren (AL), and CAP+AL. The drugs were given by gavage 30 min before anesthesia. Blood pressure and electrocardiography (ECG) were recorded during MI/R procedures. The heart tissue and plasma was kept so as to evaluate the total oxidant (TOS), antioxidant status (TAS), and creatine kinase-MB (CK-MB). Results Creatine kinase-MB was not different among the groups. Although TAS was not affected by inhibition of Ang-II production, TOS was significantly lower in the CAP and/or AL groups than in the MI/R group. Furthermore, oxidative stress index was significantly attenuated in the CAP and/or AL groups. Captopril significantly increased the duration of VT during ischemia; however, it did not have any effect on the incidence of arrhythmias. During reperfusion periods, aliskiren and its combinations with captopril significantly reduced the incidence of other types of arrhythmias. Captopril alone had no effect on the incidence of arrhythmias, but significantly increased arrhythmias score and durations of arrhythmias during reperfusion. MAP and heart rate did not show changes in any groups during ischemic and reperfusion periods. Conclusions Angiotensin-II production appears to be associated with elevated levels of reactive oxygen species, but Ang-II inhibitions increases arrhythmia, mainly by initiating ventricular ectopic beats. PMID:27889788

  11. Severity of nocturnal cardiac arrhythmias correlates with intensity of sleep apnea in men.

    PubMed

    Szaboova, E; Holoubek, D; Tomori, Z; Szabo, P; Donic, V; Stancak, B

    2013-01-01

    Various cardiac arrhythmias frequently occur in patients with sleep apnea, but complex analysis of the relationship between their severity and the probable arrhythmogenic risk factors is conflicting. The question is what cardiovascular risk factors and how strongly they are associated with the severity of cardiac arrhythmias in sleep apnea. Adult males (33 with and 16 without sleep apnea), matched for cardiovascular co-morbidity were studied by polysomnography with simultaneous ECG monitoring. Arrhythmia severity was evaluated for each subject by a special 7-degree scoring system. Laboratory, clinical, echocardiographic, carotid ultrasonographic, ambulatory blood pressure, and baroreflex sensitivity values were also assessed. Moderate sleep apnea patients had benign, but more exaggerated cardiac arrhythmias than control subjects (2.53 ± 2.49 vs. 1.13 ± 1.64 degrees of cumulative severity, p < 0.05). We confirmed strong correlations between the arrhythmia severity and known arrhythmogenic risk factors (left ventricular ejection fraction and dimensions, right ventricular diameter, baroreflex sensitivity, carotid intima-media thickness, age, previous myocardial infarction, and also apnea-hypopnea index). In multivariate modelling only the apnea-hypopnea index indicating the sleep apnea intensity remained highly significantly correlated with the cumulative arrhythmia severity (beta = 0.548, p < 0.005). In conclusion, sleep apnea modifying cardiovascular risk factors and structures or functions provoked various nocturnal arrhythmias. The proposed scoring system allowed a complex analysis of the contribution of various triggers to arrhythmogenesis and confirmed the apnea-hypopnea index as an independent risk for nocturnal cardiac arrhythmia severity in sleep apnea.

  12. Arrhythmias Following Comprehensive Stage II Surgical Palliation in Single Ventricle Patients.

    PubMed

    Wilhelm, Carolyn M; Paulus, Diane; Cua, Clifford L; Kertesz, Naomi J; Cheatham, John P; Galantowicz, Mark; Fernandez, Richard P

    2016-03-01

    Post-operative arrhythmias are common in pediatric patients following cardiac surgery. Following hybrid palliation in single ventricle patients, a comprehensive stage II palliation is performed. The incidence of arrhythmias in patients following comprehensive stage II palliation is unknown. The purpose of this study is to determine the incidence of arrhythmias following comprehensive stage II palliation. A single-center retrospective chart review was performed on all single ventricle patients undergoing a comprehensive stage II palliation from January 2010 to May 2014. Pre-operative, operative, and post-operative data were collected. A clinically significant arrhythmia was defined as an arrhythmia which led to cardiopulmonary resuscitation or required treatment with either pacing or antiarrhythmic medication. Statistical analysis was performed with Wilcoxon rank-sum test and Fisher's exact test with p < 0.05 significant. Forty-eight single ventricle patients were reviewed (32 hypoplastic left heart syndrome, 16 other single ventricle variants). Age at surgery was 185 ± 56 days. Cardiopulmonary bypass time was 259 ± 45 min. Average vasoactive-inotropic score was 5.97 ± 7.58. Six patients (12.5 %) had clinically significant arrhythmias: four sinus bradycardia, one 2:1 atrioventricular block, and one slow junctional rhythm. No tachyarrhythmias were documented for this patient population. Presence of arrhythmia was associated with elevated lactate (p = 0.04) and cardiac arrest (p = 0.002). Following comprehensive stage II palliation, single ventricle patients are at low risk for development of tachyarrhythmias. The most frequent arrhythmia seen in these patients was sinus bradycardia associated with respiratory compromise.

  13. Electromechanical coupling in the cardiac myocyte; stretch-arrhythmia feedback.

    PubMed

    ter Keurs, Henk E D J

    2011-07-01

    The macroscopic hallmarks of the normal heartbeat are rapid onset of contraction and rapid relaxation and an inotropic response to both increased end diastolic volume and increased heart rate. At the microscopic level, the calcium ion (Ca(2+)) plays a crucial role in normal cardiac contraction. This paper reviews the cycle of Ca(2+) fluxes during the normal heartbeat, which underlie the coupling between excitation and contraction (ECC) and permit a highly synchronized action of cardiac sarcomeres. Length dependence of the response of the regulatory sarcomeric proteins mediates the Frank-Starling Law of the heart. However, Ca(2+) transport may go astray in heart disease and both jeopardize the exquisite mechanism of systole and diastole and triggering arrhythmias. The interplay between weakened and strong segments in nonuniform cardiac muscle may further lead to mechanoelectric feedback-or reverse excitation contraction coupling (RECC) mediating an early diastolic Ca(2+) transient caused by the rapid force decrease during the relaxation phase. These rapid force changes in nonuniform muscle may cause arrhythmogenic Ca(2+) waves to propagate by activation of neighbouring SR by diffusing Ca(2+) ions.

  14. Real-Time Analytics for the Healthcare Industry: Arrhythmia Detection.

    PubMed

    Agneeswaran, Vijay Srinivas; Mukherjee, Joydeb; Gupta, Ashutosh; Tonpay, Pranay; Tiwari, Jayati; Agarwal, Nitin

    2013-09-01

    It is time for the healthcare industry to move from the era of "analyzing our health history" to the age of "managing the future of our health." In this article, we illustrate the importance of real-time analytics across the healthcare industry by providing a generic mechanism to reengineer traditional analytics expressed in the R programming language into Storm-based real-time analytics code. This is a powerful abstraction, since most data scientists use R to write the analytics and are not clear on how to make the data work in real-time and on high-velocity data. Our paper focuses on the applications necessary to a healthcare analytics scenario, specifically focusing on the importance of electrocardiogram (ECG) monitoring. A physician can use our framework to compare ECG reports by categorization and consequently detect Arrhythmia. The framework can read the ECG signals and uses a machine learning-based categorizer that runs within a Storm environment to compare different ECG signals. The paper also presents some performance studies of the framework to illustrate the throughput and accuracy trade-off in real-time analytics.

  15. The Brugada Syndrome: A Rare Arrhythmia Disorder with Complex Inheritance.

    PubMed

    Gourraud, Jean-Baptiste; Barc, Julien; Thollet, Aurélie; Le Scouarnec, Solena; Le Marec, Hervé; Schott, Jean-Jacques; Redon, Richard; Probst, Vincent

    2016-01-01

    For the last 10 years, applying new sequencing technologies to thousands of whole exomes has revealed the high variability of the human genome. Extreme caution should thus be taken to avoid misinterpretation when associating rare genetic variants to disease susceptibility. The Brugada syndrome (BrS) is a rare inherited arrhythmia disease associated with high risk of sudden cardiac death in the young adult. Familial inheritance has long been described as Mendelian, with autosomal dominant mode of transmission and incomplete penetrance. However, all except 1 of the 23 genes previously associated with the disease have been identified through a candidate gene approach. To date, only rare coding variants in the SCN5A gene have been significantly associated with the syndrome. However, the genotype/phenotype studies conducted in families with SCN5A mutations illustrate the complex mode of inheritance of BrS. This genetic complexity has recently been confirmed by the identification of common polymorphic alleles strongly associated with disease risk. The implication of both rare and common variants in BrS susceptibility implies that one should first define a proper genetic model for BrS predisposition prior to applying molecular diagnosis. Although long remains the way to personalized medicine against BrS, the high phenotype variability encountered in familial forms of the disease may partly find an explanation into this specific genetic architecture.

  16. Intravenous and oral amiodarone for arrhythmias in children.

    PubMed Central

    Bucknall, C A; Keeton, B R; Curry, P V; Tynan, M J; Sutherland, G R; Holt, D W

    1986-01-01

    Oral amiodarone was administered to 30 children (aged one week to 14 years) for treatment of resistant or life threatening tachycardias. Five children received initial intravenous medication. The mean duration of oral treatment ranged from two weeks to 64 months (mean 23 months). Infants required a higher oral dose than older children when this was calculated on the basis of body weight but not when it was calculated on the basis of body surface area, indicating that the prescribed dose of amiodarone for infants should be calculated on the basis of body surface area. Although plasma concentrations of amiodarone were similar in infants and children, the plasma concentration of the metabolite desethylamiodarone was lower in infants. The arrhythmias were effectively controlled, by amiodarone alone in 19 and by amiodarone in combination with other drugs in nine children; amiodarone was ineffective in the remaining two children. Unwanted effects were common but were not significantly related to the dose, duration of treatment, or plasma concentration of amiodarone when group results were analysed. Grey facial skin pigmentation developed in two patients who received high cumulative doses of amiodarone and in whom plasma concentrations of amiodarone were high. Four children with biochemical hepatic dysfunction had high plasma concentrations of amiodarone and a further four children who experienced sleep disturbance had required high doses of amiodarone. Images Fig 1 Fig 2 PMID:3756044

  17. Cardiac arrhythmia in Wilson's disease: An oversighted and overlooked entity!

    PubMed Central

    Bajaj, Bhupender Kumar; Wadhwa, Ankur; Singh, Richa; Gupta, Saurabh

    2016-01-01

    Wilson's disease is a multisystem disorder which manifests with hepatic, neurological, musculoskeletal, hematological, renal, and cardiac symptoms. The hepatic and neurological manifestations often overshadow the other system involvement including cardiac symptoms and signs, which may prove fatal. We report a case of a young female who presented with progressive parkinsonian features and dystonia for around 4 months followed 2 months later by the complaint of episodes of light-headedness. She was diagnosed to have Wilson's disease based on the presence of Kayser–Fleischer ring and laboratory parameters of copper metabolism. Electrocardiography of the patient incidentally revealed 2nd degree Mobitz type-1 atrioventricular block explaining her episodes of light-headedness. She was started on penicillamine and trihexyphenidyl. The heart block improved spontaneously. Cardiac autonomic function tests including blood pressure response to standing and heart rate response to standing were observed to be normal. We review the literature on cardiac manifestations of Wilson's disease and emphasize that patients with Wilson's disease should be assessed for cardiac arrhythmia and cardiac dysfunction as these may have therapeutic and prognostic implications. PMID:27695244

  18. Normalization of respiratory sinus arrhythmia by factoring in tidal volume.

    PubMed

    Kobayashi, H

    1998-09-01

    The amplitude of respiratory sinus arrhythmia (RSA) was measured in eight healthy young male students with special reference to the effect of tidal volume (Vt). Under simultaneously controlled respiratory frequency and Vt, the heart rate variability (HRV) of the subjects was measured. While the respiratory frequency was adjusted to either 0.25 or 0.10 Hz, the Vt was controlled at 13 different volumes for each frequency. Linear relationships between RSA amplitude and Vt were observed and close correlations were obtained for 0.25 Hz compared with 0.10 Hz. However, regression equations showed a marked variation among subjects. Furthermore, RSA amplitude was related to vital capacity. Subjects who had lower vital capacity tended to show higher RSA amplitudes at the same Vt. Therefore, the ratio (% Vt) of Vt to vital capacity is a more effective index in normalizing RSA than raw tidal volume. From these results, we have proposed a normalized RSA (RSA amplitude/% Vt) as a new index of autonomic activity that provides a constant value regardless of Vt.

  19. [Management of patients with arrhythmias undergoing thoracic surgery].

    PubMed

    Ishibashi, H; Okubo, K

    2012-07-01

    Recentry, surgical candidates have become older and have more surgical risk factors, perioperative patient management become more important than before. In the patients with significant arrhythmia observed in the preoperative period, examination of the baseline heart disease, i.e. myocardial ischemia or congestive heart failure, is mandatory and, if necessary, adequate treatment such as defibrillator, the implantation of a pacemaker, anticoagulation therapy, or other medical therapy should be performed. In the patients with atrial fibrillation, clinical prediction rules such as the congestive heart failure, hypertension, age>75, diabetes, previous stroke or transient ischemic attack (TIA) [CHADS 2] score have been developed to identify those patients at highest risk for thrombo-embolism and can be used when assessing the need for bridging anticoagulation by heparin prior to surgery. The electrical stimulus from electrocautery may inhibit demand pacemakers or may reprogram the pacemaker. An asynchronous or non-sensing pacemaker mode is recommended in patients who are pacemaker dependent and whose underlying rhythm is unreliable. The device has to be checked to ensure appropriate programming and sensing pacing thresholds after surgery. The implantable cardioverter defibrillator should be turned off during surgery and switched on in the recovery phase before discharge to the ward.

  20. Exact coherent structures: from fluid turbulence to cardiac arrhythmias

    NASA Astrophysics Data System (ADS)

    Grigoriev, Roman; Marcotte, Christopher; Byrne, Gregory

    2014-03-01

    Ventricular fibrillation, a life threatening cardiac arrhythmia, is an example of spatiotemporally chaotic state dominated by multiple interacting spiral waves. Recent studies of weak fluid turbulence suggest that spatiotemporal chaos in general can be understood as a walk among exact unstable regular solutions (exact coherent states, ECS) of nonlinear evolution equations. Several classes of ECS are believed to play a dominant role; most typically these are equilibria and periodic orbits or relative equilibria and relative periodic orbits for systems with global continuous symmetries. Numerical methods originally developed in the context of fluid turbulence can also be applied to models of cardiac dynamics which possess translational and rotational symmetries and, indeed, allowed us to identify relative equilibria and periodic orbits describing isolated spirals with, respectively, fixed and drifting cores. In order to find regular solutions featuring multiple interacting spirals a new approach is required that takes into consideration the dynamics of slowly drifting cores associated with local, rather than global, symmetries. We describe how local symmetries can be reduced and more general types of ECS computed that dominate spiral wave chaos in models of cardiac tissue.

  1. The Role of Late INa in Development of Cardiac Arrhythmias

    PubMed Central

    Antzelevitch, Charles; Nesterenko, Vladislav; Shryock, John C.; Rajamani, Sridharan; Song, Yejia; Belardinelli, Luiz

    2014-01-01

    Late INa is an integral part of the sodium current, which persists long after the fast-inactivating component. The magnitude of the late INa is relatively small in all species and in all types of cardiomyocytes as compared with the amplitude of the fast sodium current, but it contributes significantly to the shape and duration of the action potential. This late component had been shown to increase in several acquired or congenital conditions, including hypoxia, oxidative stress, and heart failure, or due to mutations in SCN5A, which encodes the α-subunit of the sodium channel, as well as in channel-interacting proteins, including multiple β subunits and anchoring proteins. Patients with enhanced late INa exhibit the type-3 long QT syndrome (LQT3) characterized by high propensity for the life-threatening ventricular arrhythmias, such as Torsade de Pointes (TdP), as well as for atrial fibrillation. There are several distinct mechanisms of arrhythmogenesis due to abnormal late INa, including abnormal automaticity, early and delayed afterdepolarization-induced triggered activity, and dramatic increase of ventricular dispersion of repolarization. Many local anesthetic and antiarrhythmic agents have a higher potency to block late INa as compared with fast INa. Several novel compounds, including ranolazine, GS-458967, and F15845, appear to be the most selective inhibitors of cardiac late INa reported to date. Selective inhibition of late INa is expected to be an effective strategy for correcting these acquired and congenital channelopathies. PMID:24737235

  2. Clinical impact of genetic studies in lethal inherited cardiac arrhythmias.

    PubMed

    Shimizu, Wataru

    2008-12-01

    Over the past decade, molecular genetic studies have established a link between a number of inherited cardiac arrhythmias, including congenital long QT syndrome (LQTS) and Brugada syndrome (BrS), and mutations in genes encoding for ion channels or other membrane components. Twelve forms of LQTS have been identified in 50-70% of clinically affected patients. Genotype-phenotype correlations have been rigorously investigated in LQT1, LQT2 and LQT3 syndromes, which constitute more than 90% of genotyped LQTS patients, enabling stratification of risk and effective treatment of genotyped patients. Genotype-specific triggers for both the cardiac events and the clinical course have been reported, and genotype-specific therapy has been already introduced. More recently, mutation site-specific differences in the clinical phenotype have been reported in LQT1 and LQT2 patients, indicating the possibility of mutation site-specific management or treatment. In contrast, only one-third of BrS patients can be genotyped, and data on genotype-phenotype relationships in clinical studies are limited. A Haplotype B consisting of 6 individual DNA polymorphisms within the proximal promoter region of the SCN5A gene was recently identified only in Asians (frequency 22%). Individuals with Haplotype B show significantly longer duration of both PQ and QRS than those without Haplotype B, indicating that Haplotype B likely contributes to the higher incidence of BrS in Asian populations.

  3. Ryanodine receptor-mediated arrhythmias and sudden cardiac death

    PubMed Central

    Blayney, Lynda M.; Lai, F. Anthony

    2009-01-01

    The cardiac ryanodine receptor-Ca2+ release channel (RyR2) is an essential sarcoplasmic reticulum (SR) transmembrane protein that plays a central role in excitation–contraction coupling (ECC) in cardiomyocytes. Aberrant spontaneous, diastolic Ca2+ leak from the SR due to dysfunctional RyR2 contributes to the formation of delayed after-depolarisations, which are thought to underlie the fatal arrhythmia that occurs in both heart failure (HF) and in catecholaminergic polymorphic ventricular tachycardia (CPVT). CPVT is an inherited disorder associated with mutations in either the RyR2 or a SR luminal protein, calsequestrin. RyR2 shows normal function at rest in CPVT but the RyR2 dysfunction is unmasked by physical exercise or emotional stress, suggesting abnormal RyR2 activation as an underlying mechanism. Several potential mechanisms have been advanced to explain the dysfunctional RyR2 observed in HF and CPVT, including enhanced RyR2 phosphorylation status, altered RyR2 regulation at luminal/cytoplasmic sites and perturbed RyR2 intra/inter-molecular interactions. This review considers RyR2 dysfunction in the context of the structural and functional modulation of the channel, and potential therapeutic strategies to stabilise RyR2 function in cardiac pathology. PMID:19345240

  4. Beyond pure parasystole: promises and problems in modeling complex arrhythmias.

    PubMed

    Courtemanche, M; Glass, L; Rosengarten, M D; Goldberger, A L

    1989-08-01

    The dynamics of pure parasystole, a cardiac arrhythmia in which two competing pacemakers fire independently, have recently been fully characterized. This model is now extended in an attempt to account for the more complex dynamics occurring with modulated parasystole, in which there exists nonlinear interaction between the sinus node and the ectopic ventricular focus. Theoretical analysis of modulated parasystole reveals three types of dynamics: entrainment, quasiperiodicity, and chaos. Rhythms associated with quasiperiodicity obey a set of rules derived from pure parasystole. This model is applied to the interpretation of continuous electrocardiographic data sets from three patients with complicated patterns of ventricular ectopic activity. We describe several new statistical properties of these records, related to the number of intervening sinus beats between ectopic events, that are essential in characterizing the dynamics and testing mathematical models. Detailed comparison between data and theory in these cases show substantial areas of agreement as well as potentially important discrepancies. These findings have implications for understanding the dynamics of the heartbeat in normal and pathological conditions.

  5. Zygotic LvBMP5-8 is required for skeletal patterning and for left-right but not dorsal-ventral specification in the sea urchin embryo.

    PubMed

    Piacentino, Michael L; Chung, Oliver; Ramachandran, Janani; Zuch, Daniel T; Yu, Jia; Conaway, Evan A; Reyna, Arlene E; Bradham, Cynthia A

    2016-04-01

    Skeletal patterning in the sea urchin embryo requires coordinated signaling between the pattern-dictating ectoderm and the skeletogenic primary mesenchyme cells (PMCs); recent studies have begun to uncover the molecular basis for this process. Using an unbiased RNA-Seq-based screen, we have previously identified the TGF-ß superfamily ligand, LvBMP5-8, as a skeletal patterning gene in Lytechinus variegatus embryos. This result is surprising, since both BMP5-8 and BMP2/4 ligands have been implicated in sea urchin dorsal-ventral (DV) and left-right (LR) axis specification. Here, we demonstrate that zygotic LvBMP5-8 is required for normal skeletal patterning on the left side, as well as for normal PMC positioning during gastrulation. Zygotic LvBMP5-8 is required for expression of the left-side marker soxE, suggesting that LvBMP5-8 is required for left-side specification. Interestingly, we also find that LvBMP5-8 knockdown suppresses serotonergic neurogenesis on the left side. While LvBMP5-8 overexpression is sufficient to dorsalize embryos, we find that zygotic LvBMP5-8 is not required for normal DV specification or development. In addition, ectopic LvBMP5-8 does not dorsalize LvBMP2/4 morphant embryos, indicating that, in the absence of BMP2/4, BMP5-8 is insufficient to specify dorsal. Taken together, our data demonstrate that zygotic LvBMP5-8 signaling is essential for left-side specification, and for normal left-side skeletal and neural patterning, but not for DV specification. Thus, while both BMP2/4 and BMP5-8 regulate LR axis specification, BMP2/4 but not zygotic BMP5-8 regulates DV axis specification in sea urchin embryos.

  6. Sympathetic restraint of respiratory sinus arrhythmia: implications for vagal-cardiac tone assessment in humans

    NASA Technical Reports Server (NTRS)

    Taylor, J. A.; Myers, C. W.; Halliwill, J. R.; Seidel, H.; Eckberg, D. L.

    2001-01-01

    Clinicians and experimentalists routinely estimate vagal-cardiac nerve traffic from respiratory sinus arrhythmia. However, evidence suggests that sympathetic mechanisms may also modulate respiratory sinus arrhythmia. Our study examined modulation of respiratory sinus arrhythmia by sympathetic outflow. We measured R-R interval spectral power in 10 volunteers that breathed sequentially at 13 frequencies, from 15 to 3 breaths/min, before and after beta-adrenergic blockade. We fitted changes of respiratory frequency R-R interval spectral power with a damped oscillator model: frequency-dependent oscillations with a resonant frequency, generated by driving forces and modified by damping influences. beta-Adrenergic blockade enhanced respiratory sinus arrhythmia at all frequencies (at some, fourfold). The damped oscillator model fit experimental data well (39 of 40 ramps; r = 0.86 +/- 0.02). beta-Adrenergic blockade increased respiratory sinus arrhythmia by amplifying respiration-related driving forces (P < 0.05), without altering resonant frequency or damping influences. Both spectral power data and the damped oscillator model indicate that cardiac sympathetic outflow markedly reduces heart period oscillations at all frequencies. This challenges the notion that respiratory sinus arrhythmia is mediated simply by vagal-cardiac nerve activity. These results have important implications for clinical and experimental estimation of human vagal cardiac tone.

  7. Risk of cardiac arrhythmias during hypoglycemia in patients with type 2 diabetes and cardiovascular risk.

    PubMed

    Chow, Elaine; Bernjak, Alan; Williams, Scott; Fawdry, Robert A; Hibbert, Steve; Freeman, Jenny; Sheridan, Paul J; Heller, Simon R

    2014-05-01

    Recent trials of intensive glycemic control suggest a possible link between hypoglycemia and excess cardiovascular mortality in patients with type 2 diabetes. Hypoglycemia might cause arrhythmias through effects on cardiac repolarization and changes in cardiac autonomic activity. Our aim was to study the risk of arrhythmias during spontaneous hypoglycemia in type 2 diabetic patients with cardiovascular risk. Twenty-five insulin-treated patients with type 2 diabetes and a history of cardiovascular disease or two or more risk factors underwent simultaneous continuous interstitial glucose and ambulatory electrocardiogram monitoring. Frequency of arrhythmias, heart rate variability, and markers of cardiac repolarization were compared between hypoglycemia and euglycemia and between hyperglycemia and euglycemia matched for time of day. There were 134 h of recording at hypoglycemia, 65 h at hyperglycemia, and 1,258 h at euglycemia. Bradycardia and atrial and ventricular ectopic counts were significantly higher during nocturnal hypoglycemia compared with euglycemia. Arrhythmias were more frequent during nocturnal versus daytime hypoglycemia. Excessive compensatory vagal activation after the counterregulatory phase may account for bradycardia and associated arrhythmias. QT intervals, corrected for heart rate, >500 ms and abnormal T-wave morphology were observed during hypoglycemia in some participants. Hypoglycemia, frequently asymptomatic and prolonged, may increase the risk of arrhythmias in patients with type 2 diabetes and high cardiovascular risk. This is a plausible mechanism that could contribute to increased cardiovascular mortality during intensive glycemic therapy.

  8. Toluene and benzene inhalation influences on ventricular arrhythmias in the rat.

    PubMed

    Magos, G A; Lorenzana-Jiménez, M; Vidrio, H

    1990-01-01

    We have previously found that toluene did not share the capacity of benzene for increasing the arrhythmogenic action of epinephrine in the rat, but appeared to elicit the opposite effect. The present experiments were carried out to verify this observation in rats subjected to more severe ventricular arrhythmias. In animals previously inhaling either air, toluene or benzene and anesthetized with pentobarbital, arrhythmias were produced by coronary ligation or aconitine. In both models, toluene decreased and benzene increased the number of ectopic ventricular beats in the 30 min following induction of arrhythmia. Gas chromatographic measurement of toluene levels in the heart during and after inhalation revealed essentially constant concentrations at the time of arrhythmia evaluation, equivalent to approximately one-third the peak levels observed at the end of inhalation. Although the mechanism of the effect of toluene on arrhythmia could not be ascertained, nonspecific membrane stabilization or central serotonergic stimulation were considered as possible explanations. Since both mechanisms could be operant also in the case of benzene, the opposite effects of the solvents on arrhythmia could not be readily accounted for.

  9. Temporal changes and spatial variation of soil oxygen consumption, nitrification and denitrification rates in a tidal salt marsh of the Lagoon of Venice, Italy

    NASA Astrophysics Data System (ADS)

    Eriksson, P. G.; Svensson, J. M.; Carrer, G. M.

    2003-12-01

    The aim of the present study was to investigate seasonal and spatial patterns of soil oxygen consumption, nitrification, denitrification and fluxes of dissolved inorganic nitrogen (DIN) in a tidal salt marsh of the Lagoon of Venice, Italy. In the salt marsh, intact soil cores including overlying water were collected monthly at high tide from April to October in salt marsh creeks and in areas covered by the dominant vegetation, Limonium serotinum. In May, cores were also collected in areas with vegetation dominated by Juncus maritimus and Halimione portulacoides. In laboratory incubations at in situ temperature in the dark, flux rates of oxygen and DIN were monitored in the overlying water of the intact cores. 15N-nitrate was added to the overlying water and nitrification and denitrification were measured using isotope-dilution and -pairing techniques. The results show that highest soil oxygen consumption coincided with the highest water temperature in June and July. The highest denitrification rates were recorded in spring and autumn coinciding with the highest nitrate concentrations. Soil oxygen consumption and nitrification rates differed between sampling sites, but denitrification rates were similar among the different vegetation types. The highest rates were recorded in areas covered with L. serotinum. Burrowing soil macrofauna enhanced oxygen consumption, nitrification and denitrification in April and May. The data presented in this study indicate high temporal as well as spatial variations in the flux of oxygen and DIN, and nitrogen transformations in the tidal salt marshes of the Venice lagoon during the growth season. The results identify the salt marshes of the Venice lagoon as being metabolically very active ecosystems with a high capacity to process nitrogen.

  10. Broadband carbon monoxide laser system operating in the wavelength range of 2.5 - 8.3 {mu}m

    SciTech Connect

    Andreev, Yu M; Ionin, Andrei A; Kinyaevsky, I O; Klimachev, Yu M; Kozlov, A Yu; Kotkov, A A; Lanskii, G V; Shaiduko, A V

    2013-02-28

    A two-cascade frequency conversion of CO-laser radiation is demonstrated in a single sample of a nonlinear ZnGeP{sub 2} crystal. The crystal is pumped by a repetitively pulsed cryogenic lowpressure CO laser operating on {approx}150 vibration - rotational transitions in the wavelength range 5.0 - 7.5 {mu}m, which corresponds to the frequency range of a half octave. In the first conversion cascade, generation of second harmonic and sum frequencies of various pairs of CO-laser radiation give {approx}350 emission lines in the wavelength range 2.5 - 3.7 {mu}m. In the second cascade, by mixing the radiation converted in the first cascade with the residual radiation of the CO laser we have obtained {approx}90 lines in the range 4.3 - 5.0 {mu}m and more than 80 lines in the range 7.5 - 8.3 {mu}m. Thus, using a single sample of the nonlinear ZnGeP{sub 2} crystal pumped by the radiation of a single CO laser we have produced a source of broadband (more than one and a half octaves) laser radiation, simultaneously operating at {approx}670 lines in the wavelength range 2.5 - 8.3 {mu}m. (lasers)

  11. A Real-Time PCR Assay Based on 5.8S rRNA Gene (5.8S rDNA) for Rapid Detection of Candida from Whole Blood Samples.

    PubMed

    Guo, Yi; Yang, Jing-Xian; Liang, Guo-Wei

    2016-06-01

    The prevalence of Candida in bloodstream infections (BSIs) has increased. To date, the identification of Candida in BSIs still mainly relies on blood culture and serological tests, but they have various limitations. Therefore, a real-time PCR assay for the detection of Candida from whole blood is presented. The unique primers/probe system was designed on 5.8S rRNA gene (5.8S rDNA) of Candida genus. The analytical sensitivity was determined by numbers of positive PCRs in 12 repetitions. At the concentration of 10(1) CFU/ml blood, positive PCR rates of 100 % were obtained for C. albicans, C. parapsilosis, C. tropicalis, and C. krusei. The detection rate for C. glabrata was 75 % at 10(1) CFU/ml blood. The reaction specificity was 100 % when evaluating the assay using DNA samples from clinical isolates and human blood. The maximum CVs of intra-assay and inter-assay for the detection limit were 1.22 and 2.22 %, respectively. To assess the clinical applicability, 328 blood samples from 82 patients were prospectively tested and real-time PCR results were compared with results from blood culture. Diagnostic sensitivity of the PCR was 100 % using as gold standard blood culture, and specificity was 98.4 %. Our data suggest that the developed assay can be used in clinical laboratories as an accurate and rapid screening test for the Candida from whole blood. Although further evaluation is warranted, our assay holds promise for earlier diagnosis of candidemia.

  12. Relationships between hydrodynamic parameters and grain size in two contrasting transitional environments: The Lagoons of Venice and Cabras, Italy

    NASA Astrophysics Data System (ADS)

    Molinaroli, E.; Guerzoni, S.; De Falco, G.; Sarretta, A.; Cucco, A.; Como, S.; Simeone, S.; Perilli, A.; Magni, P.

    2009-07-01

    A comparison was made of shallow water sediments from the Lagoon of Venice (LV) and the Lagoon of Cabras (LC), comparing depositional environments and exploring the relationships between hydrodynamics and sedimentological parameters . The two water bodies are very different in size (LV: 360 km 2; LC: 22 km 2), and the sediments predominantly consist of silty-clay (LV: Mz ≈ 26 μm; LC: Mz ≈ 6 μm). However, there are large differences between the two lagoons with respect to sand (LV: mean 19%; LC: mean ~ 3%) and clay (LV: mean 20%; LC: mean 45%) contents. The Lagoon of Venice (mean depth ~ 1 m) can be considered a tidal basin, whereas the Lagoon of Cabras (mean depth ~ 2 m) has the character of a coastal lake in which wind is the main hydrodynamic forcing factor. A comparison of sediment grain-size distributions with water circulation patterns in different parts of the lagoons highlighted some interesting differences. Grain-size analyses of samples reveal a deficiency of particles around 8 μm in the LC, which is interpreted as reflecting the transition between cohesive flocs/aggregates and non-cohesive coarser silt particles, while the transition limit in the LV is ~ 20 μm. Thus, particles are cohesive below 8 μm in the LC and below ~ 20 μm in the LV. This is probably because of the differences in the clay/silt ratio, which is much lower in the LV (~ 0.3) than in LC (~ 1), conferring a "silt-dominated network structure" on most of the LV sediments. The hydrographical data used were root mean square velocity (RMSV) and water residence time (WRT), computed under the main forcing conditions. The results show a general correlation between RMSV and sortable silt in the LC, and between RMSV and coarser sediments (63-105 μm) in the LV. Some significant differences between the lagoons were detected in the degree of correlation between WRT and grain size. Root mean square velocity (~ 7 cm s - 1 in the LV and ~ 3 cm s - 1 in the LC) was a greater forcing factor in

  13. Source apportionment of wide range particle size spectra and black carbon collected at the airport of Venice (Italy)

    NASA Astrophysics Data System (ADS)

    Masiol, Mauro; Vu, Tuan V.; Beddows, David C. S.; Harrison, Roy M.

    2016-08-01

    Atmospheric particles are of high concern due to their toxic properties and effects on climate, and large airports are known as significant sources of particles. This study investigates the contribution of the Airport of Venice (Italy) to black carbon (BC), total particle number concentrations (PNC) and particle number size distributions (PNSD) over a large range (14 nm-20 μm). Continuous measurements were conducted between April and June 2014 at a site located 110 m from the main taxiway and 300 m from the runway. Results revealed no significantly elevated levels of BC and PNC, but exhibited characteristic diurnal profiles. PNSD were then analysed using both k-means cluster analysis and positive matrix factorization. Five clusters were extracted and identified as midday nucleation events, road traffic, aircraft, airport and nighttime pollution. Six factors were apportioned and identified as probable sources according to the size profiles, directional association, diurnal variation, road and airport traffic volumes and their relationships to micrometeorology and common air pollutants. Photochemical nucleation accounted for ∼44% of total number, followed by road + shipping traffic (26%). Airport-related emissions accounted for ∼20% of total PNC and showed a main mode at 80 nm and a second mode beyond the lower limit of the SMPS (<14 nm). The remaining factors accounted for less than 10% of number counts, but were relevant for total volume concentrations: nighttime nitrate, regional pollution and local resuspension. An analysis of BC levels over different wind sectors revealed no especially significant contributions from specific directions associated with the main local sources, but a potentially significant role of diurnal dynamics of the mixing layer on BC levels. The approaches adopted in this study have identified and apportioned the main sources of particles and BC at an international airport located in area affected by a complex emission scenario. The

  14. Variability of cannabis potency in the Venice area (Italy): a survey over the period 2010-2012.

    PubMed

    Zamengo, Luca; Frison, Giampietro; Bettin, Chiara; Sciarrone, Rocco

    2014-01-01

    Cannabis is the most widely used illicit substance globally, with an estimated annual prevalence in 2010 of 2.6-5.0% of the adult population. Concerns have been expressed about increases in the potency of cannabis products. A high tetrahydrocannabinol (THC) content can increase anxiety, depression, and psychotic symptoms, and can increase the risk of dependence and adverse effects on the respiratory and cardiovascular systems in regular users. The aim of this study was to report statistical data about the potency of cannabis products seized in the north-east of Italy, in a geographical area centred in Venice and extending for more than 10,000  km(2) with a population of more than two million, by investigating the variability observed in THC levels of about 4000 samples of cannabis products analyzed over the period 2010-2012. Overall median THC content showed an increasing trend over the study period from about 6.0% to 8.1% (6.2-8.9% for cannabis resin, 5.1-7.6% for herbal cannabis). The variation in the THC content of individual samples was very large, ranging from 0.3% to 31% for cannabis resin and from 0.1 to 19% for herbal cannabis. Median CBN:THC ratios showed a slightly decreasing trend over the study period, from 0.09 (2010) to 0.03 (2012), suggesting an increasing freshness of submitted materials. Median CBD:THC ratios also showed a decreasing trend over the study from about 0.52 (2010) to 0.18 (2012), likely due to the increase in submissions of materials from indoor and domestic cultivation with improved breeding methods.

  15. The effects of clam fishing on the properties of surface sediments in the lagoon of Venice, Italy

    NASA Astrophysics Data System (ADS)

    Aspen, R. J.; Vardy, S.; Perkins, R. G.; Davidson, I. R.; Bates, R.; Paterson, D. M.

    Harvesting of clams(Tapes philippinarum) has important socio-economic and environmental implications for the Venice lagoon area, Italy. Clam harvesting disrupts the structure of benthic communities but the effects upon sediment stability and surface structure remain unclear. The effect of clam fishing on the sediment properties of the lagoon bed was investigated at two different sites, a heavily fished site (San Angelo) and an infrequently fished site (San Giaccomo). Both sites were assessed for immediate impacts of fishing, using indicators of biogenic sediment stabilisation. Samples were taken at three points along three 100 m linear transects at each site prior to and post fishing. Paired samples were also taken parallel to each transect at a distance of 5m, to allow for temporal variation. Sediment stability, measured with a cohesive strength meter (CSM), was significantly higher at the less impacted site (F1,34 = 6.23, p < 0.018), was correlated with indicators of biogenic sediment stabilisation and decreased by approximately 50% following the trawling event. Concomitant decreases in chlorophyll a (chl a), colloidal-S carbohydrate and dry bulk density were observed on the transect after fishing but not adjacent to the fishing path. At the heavily impacted site, clam fishing by trawling had, in general, no significant effect on the biological and physical properties (although chl a did decrease significantly after fishing). The lack of a significant impact from fishing at the impacted site was attributed to the higher frequency of fishing occurring in this area. Hence, frequent fishing of the lagoon prevents establishment of biotic communities, preventing biostabilisation and thus reduces the stability of the surface sediment.

  16. Noninvasive Cardiac Screening in Young Athletes With Ventricular Arrhythmias

    PubMed Central

    Steriotis, Alexandros Klavdios; Nava, Andrea; Rigato, Ilaria; Mazzotti, Elisa; Daliento, Luciano; Thiene, Gaetano; Basso, Cristina; Corrado, Domenico; Bauce, Barbara

    2013-01-01

    The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Results of ECG were normal in most athletes (85%). VAs were initially detected prevalently during exercise testing (85%) and in the remaining cases on ECG and Holter monitoring. Premature ventricular complexes disappeared during exercise in 56% of subjects. Premature ventricular complexes during Holter monitoring averaged 4,700 per day, predominantly monomorphic (88%), single, and/or in couplets (79%). The most important echocardiographic findings were mitral valve prolapse in 29 patients (20%), congenital heart disease in 4 (3%), and right ventricular regional kinetic abnormalities in 5 (3.5%). On cardiac magnetic resonance imaging, right ventricular regional kinetic abnormalities were detected in 9 of 30 athletes and were diagnostic of arrhythmogenic right ventricular cardiomyopathy in only 1 athlete. Overall, 30% of athletes were judged to have potentially dangerous VAs. In asymptomatic athletes with prevalently normal ECG, most VAs can be identified by adding an exercise test during preparticipation screening. In conclusion, cardiac screening with noninvasive examinations remains a fundamental tool for the identification of a possible pathologic substrate and for the characterization of electrical instability. PMID:23219000

  17. Exploiting periodicity to extract the atrial activity in atrial arrhythmias

    NASA Astrophysics Data System (ADS)

    Llinares, Raul; Igual, Jorge

    2011-12-01

    Atrial fibrillation disorders are one of the main arrhythmias of the elderly. The atrial and ventricular activities are decoupled during an atrial fibrillation episode, and very rapid and irregular waves replace the usual atrial P-wave in a normal sinus rhythm electrocardiogram (ECG). The estimation of these wavelets is a must for clinical analysis. We propose a new approach to this problem focused on the quasiperiodicity of these wavelets. Atrial activity is characterized by a main atrial rhythm in the interval 3-12 Hz. It enables us to establish the problem as the separation of the original sources from the instantaneous linear combination of them recorded in the ECG or the extraction of only the atrial component exploiting the quasiperiodic feature of the atrial signal. This methodology implies the previous estimation of such main atrial period. We present two algorithms that separate and extract the atrial rhythm starting from a prior estimation of the main atrial frequency. The first one is an algebraic method based on the maximization of a cost function that measures the periodicity. The other one is an adaptive algorithm that exploits the decorrelation of the atrial and other signals diagonalizing the correlation matrices at multiple lags of the period of atrial activity. The algorithms are applied successfully to synthetic and real data. In simulated ECGs, the average correlation index obtained was 0.811 and 0.847, respectively. In real ECGs, the accuracy of the results was validated using spectral and temporal parameters. The average peak frequency and spectral concentration obtained were 5.550 and 5.554 Hz and 56.3 and 54.4%, respectively, and the kurtosis was 0.266 and 0.695. For validation purposes, we compared the proposed algorithms with established methods, obtaining better results for simulated and real registers.

  18. Detection and Prevention of Cardiac Arrhythmias During Space Flight

    NASA Technical Reports Server (NTRS)

    Pillai, Dilip; Rosenbaum, David S.; Liszka, Kathy J.; York, David W.; Mackin, Michael A.; Lichter, Michael J.

    2004-01-01

    There have been reports suggesting that long-duration space flight might lead to an increased risk of potentially serious heart rhythm disturbances. If space flight does, in fact, significantly decrease cardiac electrical stability, the effects could be catastrophic, potentially leading to sudden cardiac death. It will be important to determine the mechanisms underlying this phenomenon in order to prepare for long-term manned lunar and interplanetary missions and to develop appropriate countermeasures. Our hypothesis is that prolonged exposure to microgravity will alter T wave alternans measurements, decrease heart rate variance, increase QT dispersion, decrease heart rate recovery and alter QT restitution curve. A recently published study has shown that long duration spaceflights prolong cardiac conduction and repolarization. They concluded that long duration flight is associated with QT interval prolongation and may increase arrhythmia susceptibility. We propose using computer technology as a noninvasive clinical tool to detect and study clinically significant TWA during standard exercise testing using electrode systems specifically adapted for the purpose of obtaining and measuring TWA. A population of approximately 15 healthy men and 5 healthy women subjects, representative of the astronaut cohort will be asked to voluntarily participate in this study. Their blood pressure and ECG/TWA will be measured pre-flight and in-flight. Prior to flight, subjects will be asked to participate in an orientation session. Still photos will be taken of the skin where the conductive gel is used for the multi-segment sensors. Photos will be recorded preflight, immediately postflight, and several times during the proceeding week until it has been determined that any skin reaction has disappeared or that no rash is present and will not appear.

  19. A possible mechanism of halocarbon-induced cardiac sensitization arrhythmias

    PubMed Central

    Jiao, Zhe; De Jesús, Víctor R.; Iravanian, Shahriar; Campbell, Daniel P.; Xu, Jie; Vitali, Juan A.; Banach, Kathrin; Fahrenbach, John; Dudley, Samuel C.

    2011-01-01

    Cardiac sensitization is the term used for malignant ventricular arrhythmias associated with exposure to inhaled halocarbons in the presence of catecholamines. We investigated the electrophysiological changes associated with cardiomyocyte exposure to epinephrine and a halocarbon known to be associated with cardiac sensitization (halon 1301, CF3Br). Cardiomyocytes (CMs) were isolated from neonatal rats and grown on multielectrode arrays (MEAs). Upon exposure to epinephrine, the CM inter-spike interval (ISI) was decreased 14% at 10 µg/L (P<0.05) and 27% at 100 µg/L (P<0.05) as compared to baseline. Halon alone (50 mg/L) mildly prolonged the field potential (FP) duration (7%). CMs exposed to combinations of epinephrine (100 µg/L) and halon (50 mg/L) for 15 min showed a blunted increase in the ISI (35±12%) and a 38% decrease in conduction velocity (P<0.05) when compared to epinephrine alone. There was no change in field potential properties, but dephosphorylated connexin 43 (Cx43) was increased 60±16% with the combination as compared to epinephrine alone (P<0.05). Treatment with okadaic acid, a phosphatase inhibitor, prevented the Cx43 dephosphorylation and the reduction in conduction velocity upon exposure to halon and epinephrine. Moreover, the electrophysiological changes induced by epinephrine and halon were indistinguishable from those seen with the gap junction inhibitor heptanol. In conclusion, the combination of a halocarbon and epinephrine results in a unique electrophysiological signature including slow conduction that may explain, in part, the basis for cardiac sensitization. The slowing of conduction is most likely related to changes in the phosphorylation state of Cx43. PMID:16919292

  20. Effect of Different Pranayamas on Respiratory Sinus Arrhythmia

    PubMed Central

    Raj, Jeneth Berlin; Ramanathan, Meena; Trakroo, Madanmohan

    2016-01-01

    Introduction Respiratory Sinus Arrhythmia (RSA) is the differential change of Heart Rate (HR) in response to inspiration and expiration. This is a noninvasive sensitive index of parasympathetic cardiac control. Aim To evaluate changes in RSA by utilizing a simple and cost-effective analysis of electrocardiographic (ECG) tracings obtained during performance of four pranayama techniques. Materials and Methods Fifty two trained volunteers performed the following pranayamas with different ratios for inspiration and expiration: sukha (1:1), traditional (1:2), pranava (1:3) and savitri (2:1:2:1) and ECG was recorded while performing the techniques with rest period of 5 minutes in-between. HR was calculated and maximum HR during inspiration (Imax), minimum HR during expiration (Emin), differences between Imax and Emin (Δ), percentage differences between Imax and Emin (Δ%) and expiration: inspiration ratio (E:I) calculated by respective formulae. Statistical analysis was carried out using repeated measures of ANOVA with Tukey-Kramer multiple comparisons test. Results There were significant differences between groups in all five aspects namely: p= 0.0093 for mean Imax, p = 0.0009 for mean Emin, and p < 0.0001 for Δ HR (I-E), Δ% HR (I-E) and E:I ratio. Pranava pranayama produced the greatest changes in all five comparisons. Conclusion We suggest that further short and long term studies be undertaken with pranava pranayama in patients to further qualitatively and quantitatively evaluate inherent mechanisms of this simple technique. Addition of these cost-effective techniques to the medical armory will help patients of rhythm disorders and other cardiovascular conditions. PMID:27134863

  1. 5,8,11,14-Eicosatetraynoic acid-induced destruction of mitochondria in human prostate cells (PC-3).

    SciTech Connect

    Anderson, K. M.; Seed, T. M.; Wilson, D. E.; Harris, J. E.; Biological and Medical Research; Rush Medical Coll.

    1992-01-01

    Culturing human prostate PC-3 cells for 4, 24, or 72 h in the presence of 5,8,11,14-eicosatetraynoic acid (ETYA), an inhibitor of arachidonic acid metabolism and cholesterol biosynthesis, markedly altered the morphology and reduced the number of mitochondria in the treated cells. Using quantitative electron microscopic morphometry, we documented changes in the number, form, area, matrix density, and integrity of the cristae and limiting membranes of mitochondria in cells cultured with ETYA. The inhibition of cholesterol synthesis or the substitution of ETYA for polyunsaturated fatty acids in the inner membrane may participate in the disruption of the mitochondria, which resembles the morphologic sequelae of oxidative stress. If sufficiently extensive, these changes could contribute to the inhibition of cellular proliferation by ETYA.

  2. Psoralen-deoxyribonucleic acid photoreaction. Characterization of the monoaddition products from 8-methoxypsoralen and 4,5',8-trimethylpsoralen

    SciTech Connect

    Kanne, D.; Straub, K.; Rapoport, H.; Hearst, J.E.

    1982-01-01

    The isolation and structural characterization are described of the major monoaddition products formed in the photoreaction of two naturally occurring psoralens, 8-methoxypsoralen and 4,5',8-trimethylpsoralen, with high molecular weight, double-stranded DNA. Hydrolysis of the psoralen-modified DNA and subsequent chromatography resulted in the isolation of four modified nucleosides from each psoralen. Structural characterization was accomplished by mass spectrometry and /sup 1/H NMR analysis. The major products, accounting for 44 to 52% of the covalently bound psoralen, are two diastereomeric thymidine adducts formed by cycloaddition between the 5,6 double bond of the pyrimidine and the 4',5' (furan) double bond of the psoralen. All of the isolated adducts have cis-syn stereochemistry. The stereochemistry and product distribution of the adducts are determined in part by the constraints imposed by the DNA helix on the geometry of the noncovalent intercalation complex formed by psoralen and DNA prior to irradiation.

  3. Repair of 4,5',8-trimethylpsoralen monoadducts and cross-links by the Escherichia coli UvrABC endonuclease

    SciTech Connect

    Jones, B.K.; Yeung, A.T. )

    1988-11-01

    Using an oligonucleotide model substrate, the authors observed two unusual mechanisms of UvrABC endonuclease in the repair of 4,5',8-trimethylpsoralen monaddducts and cross-links. (i) UvrABC endonuclease usually incises a psoralen monadduct only on the damaged strand. However, for one of the monadducts they studied, incision on the complementary undamaged strand was also observed at a very low frequency, as though the adduct were on the thymine across from the damaged strand. Although the details of the erroneous incision are not yet know, such erroneous incision is potentially mutagenic. (ii) In cross-link repair, they observed that the UvrABC endonuclease incises the cross-linked DNA on either the furan side strand or the pyrone side strand. The incisions are not equally efficient. These data suggest that the structure of a psoralen cross-link, as seen by a repair enzyme, varies with the DNA sequence.

  4. Texture and anisotropy of yield strength in multistep isothermally forged Mg-5.8Zn-0.65Zr alloy

    NASA Astrophysics Data System (ADS)

    Nugmanov, D. R.; Sitdikov, O. Sh; Markushev, M. V.

    2015-04-01

    The effect of multistep isothermal forging (MIF) on microstructure, texture and anisotropy of ambient temperature yield strength of MA14 (Mg-5.8Mg-0.65Zr (%, wt)) magnesium alloy hot-pressed rod was analyzed. It has been found that the initial axial texture is quite stable under 1st MIF step up to strain e∼4.2 at 400°C and has been gradually transformed into much weaker single-peak one at further processing at 300 and 200°C to total strain of 10.2. Such texture changes were accompanied by strong grain refinement, along with significant reduction of the alloy strength anisotropy.

  5. Experimental Investigation of the Low-Speed Aerodynamic Characteristics of a 5.8-Percent Scale Hybrid Wing Body Configuration

    NASA Technical Reports Server (NTRS)

    Gatlin, Gregory M.; Vicroy, Dan D.; Carter, Melissa B.

    2012-01-01

    A low-speed experimental investigation has been conducted on a 5.8-percent scale Hybrid Wing Body configuration in the NASA Langley 14- by 22-Foot Subsonic Tunnel. This Hybrid Wing Body (HWB) configuration was designed with specific intention to support the NASA Environmentally Responsible Aviation (ERA) Project goals of reduced noise, emissions, and fuel burn. This HWB configuration incorporates twin, podded nacelles mounted on the vehicle upper surface between twin vertical tails. Low-speed aerodynamic characteristics were assessed through the acquisition of force and moment, surface pressure, and flow visualization data. Longitudinal and lateral-directional characteristics were investigated on this multi-component model. The effects of a drooped leading edge, longitudinal flow-through nacelle location, vertical tail shape and position, elevon deflection, and rudder deflection have been studied. The basic configuration aerodynamics, as well as the effects of these configuration variations, are presented in this paper.

  6. Synthesis and Evaluation of Antitumor Activity of Novel N-Acyllavendamycin Analogues and Quinoline -5,8- diones

    PubMed Central

    Behforouz, Mohammad; Cai, Wen; Mohammadi, Farahnaz; Stocksdale, Mark G.; Gu, Zhengxiang; Ahmadian, Mohammad; Baty, Darric E.; Etling, Michele R.; Al-Anzi, Charmaine H.; Swiftney, Tyson M.; Tanzer, Lee R.; Merriman, Ronald R.; Behforouz, Nancy C.

    2007-01-01

    A series of 7-N-acyllavendamycins with zero, one or two substitutents at the C-2′, C-3′ and C-11′ were synthesized through short and efficient methods. Pictet-Spengler condensation of 7-N-acylamino-2-formylquinoline-5,8-diones with tryptamine or tryptophans produced the desired lavendamycins. Screening data on a panel of three ras oncogene transformed cell lines and the non-transformed parent cell line showed that a significant number of these analogues are potent antitumor agents and appear to be particularly active against K-ras transformed cells. Compared with the corresponding quinolinediones, these novel lavendamycins are much more inhibitory toward the transformed cells indicating that the β-carboline moiety of the lavendamycin analogues plays an important role in its potency and selective toxicity. PMID:17035024

  7. Loop mediated isothermal amplification of 5.8S rDNA for specific detection of Tritrichomonas foetus.

    PubMed

    Oyhenart, Jorge; Martínez, Florencia; Ramírez, Rosana; Fort, Marcelo; Breccia, Javier D

    2013-03-31

    Tritrichomonas foetus is the causative agent of bovine trichomonosis, a sexually transmitted disease leading to infertility and abortion. A test based on loop mediated isothermal amplification (LAMP) targeting the 5.8S rDNA subunit was designed for the specific identification of T. foetus. The LAMP assay was validated using 28 T. foetus and 35 non-T. foetus trichomonads strains. It did not exhibit cross-reaction with closely related parasites commonly found in smegma cultures like Tetratrichomonas spp. and Pentatrichomonas hominis. Bovine smegma did not show interferences for the detection of the parasite and, the sensitivity of the method (4×10(3) CFU/mL, approximately 10 cells/reaction) was slightly higher than that found for PCR amplification with TFR3 and TFR4 primers. The LAMP approach has potential applications for diagnosis and control of T. foetus and, practical use for low skill operators in rural areas.

  8. Structural and dynamical characterization of the Miz-1 zinc fingers 5-8 by solution-state NMR.

    PubMed

    Bernard, David; Bédard, Mikaël; Bilodeau, Josée; Lavigne, Pierre

    2013-10-01

    Myc-interacting zinc finger protein-1 (Miz-1) is a BTB/POZ transcription factor that activates the transcription of cytostatic genes, such as p15(INK4B) or p21(CIP1). The C-terminus of Miz-1 contains 13 consensus C2H2 zinc finger domains (ZF). ZFs 1-4 have been shown to interact with SMAD3/4, while the remaining ZFs are expected to bind the promoters of target genes. We have noted unusual features in ZF 5 and the linker between ZFs 5 and 6. Indeed, a glutamate is found instead of the conserved basic residue two positions before the second zinc-coordinating histidine on the ZF 5 helix, and the linker sequence is DTDKE in place of the classical TGEKP sequence. In a canonical ββα fold, such unusual primary structure elements should cause severe electrostatic repulsions. In this context, we have characterized the structure and the dynamics of a Miz-1 construct comprising ZFs 5-8 (Miz 5-8) by solution-state NMR. Whilst ZFs 5, 7 and 8 were shown to adopt the classical ββα fold for C2H2 ZFs, the number of long-range NOEs was insufficient to define a classical fold for ZF 6. We show by using (15)N-relaxation dispersion experiments that this lack of NOEs is due to the presence of extensive motions on the μs-ms timescale. Since this negatively charged region would have to be located near the phosphodiester backbone in a DNA complex, we propose that in addition to promoting conformational searches, it could serve as a hinge region to keep ZFs 1-4 away from DNA.

  9. The Matching of Sinus Arrhythmia to Respiration: Are Trauma Patients without Serious Injury Comparable to Healthy Laboratory Subjects?

    DTIC Science & Technology

    2014-08-01

    the correlation between sinus arrhythmia (SA) rate, heart rate (HR), and respiratory rate (RR). Most segments with 2.4 ≤ HR/RR < 4.8 exhibited SA...variation (sinus arrhythmia [SA]; rhythmic fluctuations in heart rate [HR]) is wholly driven by the respiratory rate (RR), such that their rates will be...The Matching of Sinus Arrhythmia to Respiration: Are Trauma Patients without Serious Injury Comparable to Healthy Laboratory Subjects? Xiaoxiao

  10. Mandatory and recommended vaccination in the EU, Iceland and Norway: results of the VENICE 2010 survey on the ways of implementing national vaccination programmes.

    PubMed

    Haverkate, M; D'Ancona, F; Giambi, C; Johansen, K; Lopalco, P L; Cozza, V; Appelgren, E

    2012-05-31

    This report provides an updated overview of recommended and mandatory vaccinations in the European Union (EU), Iceland and Norway, considering the differences in vaccine programme implementation between countries. In 2010, the Vaccine European New Integrated Collaboration Effort (VENICE) network, conducted a survey among the VENICE project gatekeepers to learn more about how national vaccination programmes are implemented, whether recommended or mandatory. Information was collected from all 27 EU Member States, Iceland and Norway. In total 15 countries do not have any mandatory vaccinations; the remaining 14 have at least one mandatory vaccination included in their programme. Vaccination against polio is mandatory for both children and adults in 12 countries; diphtheria and tetanus vaccination in 11 countries and hepatitis B vaccination in 10 countries. For eight of the 15 vaccines considered, some countries have a mixed strategy of recommended and mandatory vaccinations. Mandatory vaccination may be considered as a way of improving compliance to vaccination programmes. However, compliance with many programmes in Europe is high, using only recommendations. More information about the diversity in vaccine offer at European level may help countries to adapt vaccination strategies based on the experience of other countries. However, any proposal on vaccine strategies should be developed taking into consideration the local context habits.

  11. Clinical Profile of Cardiac Arrhythmias in Children Attending the Out Patient Department of a Tertiary Paediatric Care Centre in Chennai

    PubMed Central

    Sundararajan, Premkumar; Sangaralingam, Thangavelu

    2016-01-01

    Introduction The presentation of symptoms of paediatric arrhythmias vary depending on the age and underlying heart disease. Physical examination of children with important arrhythmias may be entirely normal. Aim Aim is to study the characteristics of cardiac arrhythmias in paediatric patients in a tertiary paediatric care centre in Chennai, India. Materials and Methods The participants (n=60) were from birth to 12 years of age. Patients with sinus arrhythmias, sinus tachycardia and sinus bradycardia were excluded. Proportions of various parameters of interest like clinical features, age and sex distribution and underlying heart disease of children presenting with cardiac arrhythmias were arrived. Statistical analysis was performed using SPSS version 16.0. Results Ventricular ectopics were the most common type of arrhythmias observed in the present study followed by Sinus Node Dysfunction (SND). The most common type of SND was sino atrial arrest. Supra ventricular tachycardia was the most frequently sustained tachyarrhythmia in the present study. An increased association of WPW (Wolf Parkinson White Syndrome) with specific congenital cardiac defects was noted. Conclusion Cardiac arrhythmias in children can present at anytime from fetal life to adolescence and their recognition requires high index of suspicion. While majority of children with arrhythmias have structurally normal heart, they are frequently encountered in children with underlying heart disease. Treatment of paediatric arrhythmias should be guided by the severity of the patient, the structure and function of the heart. PMID:28208963

  12. MS-551 and KCB-328, two class III drugs aggravated adrenaline-induced arrhythmias.

    PubMed

    Xue, Y; Yamada, C; Aye, N N; Hashimoto, K

    1998-08-01

    We investigated the proarrhythmic effects of MS-551 and KCB-328, class III antiarrhythmic drugs using adrenaline-induced arrhythmia models in halothane anaesthetized, closed-chest dogs. In the control period, adrenaline, starting from a low dose of 0.25 to up to 1.0 microg/kg/50 s i.v., was injected to determine the arrhythmia inducing dose and the non-inducing dose. After MS-551 or KCB-328 administration, the adrenaline injection was repeated and the interval between the injection and the occurrence of arrhythmia (latent interval), the changes in arrhythmic ratio (as calculated by dividing the number of ventricular premature contraction by the number of the total heart rate) and the severity of arrhythmia were observed. MS-551 infusion, 1 mg/kg/30 min, decreased the heart rate (HR) by 16% (P<0.01) and prolonged the QTc interval by 20% (P<0.01). During the 30 min of MS-551 infusion, arrhythmias occurred in three out of seven dogs (torsades de pointes (TdP) type VT in one dog). After these arrhythmias disappeared, MS-551 decreased the latent interval of the adrenaline arrhythmias produced by the inducing dose (30+/-2 s compared with 43+/-3 s of the control interval, P < 0.05), increased the arrhythmic ratio (P<0.05) and induced arrhythmias by non-inducing adrenaline doses (P<0.05). Effect of a new class III drug KCB-328 infusion, 0.3 mg/kg/30 min, was compared witih MS-551 using the same model. KCB-328 decreased the HR by 21% (P<0.01) and prolonged the QTc interval by 25% (P<0.01). During the 30 min of infusion, arrhythmias occurred in five out of seven dogs (TdP in two dogs). KCB-328 also decreased the latent interval of the adrenaline arrhythmias produced by the inducing doses (31+/-3 s compared with 49+/-7 s of the control period, P<0.05), but did not significantly alter the arrhythmic ratio. Adrenaline induced TdP only after MS-551 or KCB-328 was administered, i.e. after MS-551, 1 mg/kg/30 min, 3/7 versus 0/7 in the control; KCB, 0.3 mg/kg/30 min, 3/7 versus 0

  13. Oral fluoroquinolone use and serious arrhythmia: bi-national cohort study

    PubMed Central

    Svanström, Henrik; Melbye, Mads; Pasternak, Björn; Hviid, Anders

    2016-01-01

    Objective To evaluate if oral fluoroquinolone use is associated with an increased risk of serious arrhythmia. Design Bi-national cohort study, linking register data on filled prescriptions, cases of serious arrhythmia, and patient characteristics. Setting Denmark, 1997-2011; Sweden, 2006-13. Participants The study cohort was derived from a source population of all Danish and Swedish adults, aged 40 to 79 years. 909 656 courses of fluoroquinolone use (ciprofloxacin 82.6%, norfloxacin 12.1%, ofloxacin 3.2%, moxifloxacin 1.2%, and other fluoroquinolones 0.9%) and 909 656 courses of penicillin V use, matched 1:1 on propensity score, were included. Main outcome measure The main outcome was risk of serious arrhythmia (fatal and non-fatal), comparing courses of fluoroquinolone use with courses of penicillin V use (an antibiotic with no pro-arrhythmic effect). The risk period of interest was current use, defined as days 0-7 of treatment. Subgroup analyses were conducted according to country, sex, age, underlying cardiovascular disease, concomitant use of drugs known to increase the risk of torsades de pointes, fluoroquinolone type, and levels of arrhythmia risk score. Results 144 cases of serious arrhythmia occurred during follow-up, 66 among current fluoroquinolone users (incidence rate 3.4 per 1000 person years) and 78 among current penicillin users (4.0 per 1000 person years); comparing oral fluoroquinolone treatment with penicillin V, the rate ratio was 0.85 (95% confidence interval 0.61 to 1.18). Compared with penicillin V, the absolute risk difference was −13 (95% confidence interval −35 to 16) cases of serious arrhythmia per 1 000 000 courses of fluoroquinolones. The risk of serious arrhythmia was not statistically significantly increased in any of the subgroups, including analyses by fluoroquinolone type. Conclusions Contrary to previous reports, oral fluoroquinolone treatment was not associated with an increased risk of serious arrhythmia in the

  14. Prolonged Oral Administration of Oleuropein Might Protect Heart against Aconitine-induced Arrhythmia

    PubMed Central

    Esmailidehaj, Mansour; Mirhosseini, Seyed-Jalil; Rezvani, Mohammad Ebrahim; Rasoulian, Bahram; Mosaddeghmehrjardi, Mohammad Hossein; Haghshenas, Damoon

    2012-01-01

    In this study, it was surveyed to know whether an oral single dose of oleuropein could mimic the cardiac preconditioning in rats’ hearts or whether its prolonged oral administration could protect the heart against the aconitine-induced arrhythmia in rats. Eighty male Wistar rats were divided into two series (n = 8 in each group). In the first series, all groups (except the control (Con) group) were given a single oral dose of oleuropein (20 mg/Kg) 1, 3, 24 and 48 h before the infusion of aconitine. In the second series, except the Con group, the other four groups were given oral oleuropein (20 mg/Kg/day) for 3, 7, 14 and 28 days, before the infusion of aconitine. Electrocardiogram was recorded to monitor arrhythmia. Data of the first series showed that the initiation time of arrhythmia, the initiation of ventricular tachycardia (VT), the numbers of reversible ventricular fibrillation (VF) and the death time had no significant difference compared with Con group. In the second series, a significant protection was occurred only in the 28 days group that was evident with increased initiation time of arrhythmia, increased initiation time of VT, and increased the number of reversible VF and death time in compared to the Con group. The findings of this study show that the oral administration of a single dose of oleuropein could not mimic the preconditioning effects in rat hearts, but the prolonged administration of oleuropein for about four weeks could protect the heart against aconitine-induced arrhythmia. PMID:24250560

  15. Severe hypoglycemia-induced lethal cardiac arrhythmias are mediated by sympathoadrenal activation.

    PubMed

    Reno, Candace M; Daphna-Iken, Dorit; Chen, Y Stefanie; VanderWeele, Jennifer; Jethi, Krishan; Fisher, Simon J

    2013-10-01

    For people with insulin-treated diabetes, severe hypoglycemia can be lethal, though potential mechanisms involved are poorly understood. To investigate how severe hypoglycemia can be fatal, hyperinsulinemic, severe hypoglycemic (10-15 mg/dL) clamps were performed in Sprague-Dawley rats with simultaneous electrocardiogram monitoring. With goals of reducing hypoglycemia-induced mortality, the hypotheses tested were that: 1) antecedent glycemic control impacts mortality associated with severe hypoglycemia; 2) with limitation of hypokalemia, potassium supplementation could limit hypoglycemia-associated deaths; 3) with prevention of central neuroglycopenia, brain glucose infusion could prevent hypoglycemia-associated arrhythmias and deaths; and 4) with limitation of sympathoadrenal activation, adrenergic blockers could prevent hypoglycemia-induced arrhythmic deaths. Severe hypoglycemia-induced mortality was noted to be worsened by diabetes, but recurrent antecedent hypoglycemia markedly improved the ability to survive an episode of severe hypoglycemia. Potassium supplementation tended to reduce mortality. Severe hypoglycemia caused numerous cardiac arrhythmias including premature ventricular contractions, tachycardia, and high-degree heart block. Intracerebroventricular glucose infusion reduced severe hypoglycemia-induced arrhythmias and overall mortality. β-Adrenergic blockade markedly reduced cardiac arrhythmias and completely abrogated deaths due to severe hypoglycemia. Under conditions studied, sudden deaths caused by insulin-induced severe hypoglycemia were mediated by lethal cardiac arrhythmias triggered by brain neuroglycopenia and the marked sympathoadrenal response.

  16. Protective effects of isorhynchophylline on cardiac arrhythmias in rats and guinea pigs.

    PubMed

    Gan, Runtao; Dong, Guo; Yu, Jiangbo; Wang, Xu; Fu, Songbin; Yang, Shusen

    2011-09-01

    As one important constituent extracted from a traditional Chinese medicine, Uncaria Rhynchophylla Miq Jacks, isorhynchophylline has been used to treat hypertension, epilepsy, headache, and other illnesses. Whether isorhynchophylline protects hearts against cardiac arrhythmias is still incompletely investigated. This study was therefore aimed to examine the preventive effects of isorhynchophylline on heart arrhythmias in guinea pigs and rats and then explore their electrophysiological mechanisms. In vivo, ouabain and calcium chloride were used to establish experimental arrhythmic models in guinea pigs and rats. In vitro, the whole-cell patch-lamp technique was used to study the effect of isorhynchophylline on action potential duration and calcium channels in acutely isolated guinea pig and rat cardiomyocytes. The dose of ouabain required to induce cardiac arrhythmias was much larger in guinea pigs administered with isorhynchophylline. Additionally, the onset time of cardiac arrhythmias induced by calcium chloride was prolonged, and the duration was shortened in rats pretreated with isorhynchophylline. The further study showed that isorhynchophylline could significantly decrease action potential duration and inhibit calcium currents in isolated guinea pig and rat cardiomyocytes in a dose-dependent manner. In summary, isorhynchophylline played a remarkably preventive role in cardiac arrhythmias through the inhibition of calcium currents in rats and guinea pigs.

  17. Electrical alternans during rest and exercise as predictors of vulnerability to ventricular arrhythmias

    NASA Technical Reports Server (NTRS)

    Estes, N. A. 3rd; Michaud, G.; Zipes, D. P.; El-Sherif, N.; Venditti, F. J.; Rosenbaum, D. S.; Albrecht, P.; Wang, P. J.; Cohen, R. J.

    1997-01-01

    This investigation was performed to evaluate the feasibility of detecting repolarization alternans with the heart rate elevated with a bicycle exercise protocol. Sensitive spectral signal-processing techniques are able to detect beat-to-beat alternation of the amplitude of the T wave, which is not visible on standard electrocardiogram. Previous animal and human investigations using atrial or ventricular pacing have demonstrated that T-wave alternans is a marker of vulnerability to ventricular arrhythmias. Using a spectral analysis technique incorporating noise reduction signal-processing software, we evaluated electrical alternans at rest and with the heart rate elevated during a bicycle exercise protocol. In this study we defined optimal criteria for electrical alternans to separate patients from those without inducible arrhythmias. Alternans and signal-averaged electrocardiographic results were compared with the results of vulnerability to ventricular arrhythmias as defined by induction of sustained ventricular tachycardia or fibrillation at electrophysiologic evaluation. In 27 patients alternans recorded at rest and with exercise had a sensitivity of 89%, specificity of 75%, and overall clinical accuracy of 80% (p <0.003). In this patient population the signal-averaged electrocardiogram was not a significant predictor of arrhythmia vulnerability. This is the first study to report that repolarization alternans can be detected with heart rate elevated with a bicycle exercise protocol. Alternans measured using this technique is an accurate predictor of arrhythmia inducibility.

  18. Cardiac Arrhythmias in Patients with Chronic Kidney Disease: Implications of Renal Failure for Antiarrhythmic Drug Therapy.

    PubMed

    Potpara, Tatjana S; Jokic, Vera; Dagres, Nikolaos; Marin, Francisco; Prostran, Milica S; Blomstrom-Lundqvist, Carina; Lip, Gregory Y H

    2016-01-01

    The kidney has numerous complex interactions with the heart, including shared risk factors (e.g., hypertension, dyslipidemia, etc.) and mutual amplification of morbidity and mortality. Both cardiovascular diseases and chronic kidney disease (CKD) may cause various alterations in cardiovascular system, metabolic homeostasis and autonomic nervous system that may facilitate the occurrence of cardiac arrhythmias. Also, pre-existent or incident cardiac arrhythmias such as atrial fibrillation (AF) may accelerate the progression of CKD. Patients with CKD may experience various cardiac rhythm disturbances including sudden cardiac death. Contemporary management of cardiac arrhythmias includes the use of antiarrhythmic drugs (AADs), catheter ablation and cardiac implantable electronic devices (CIEDs). Importantly, AADs are not used only as the principal treatment strategy, but also as an adjunct therapy in combination with CIEDs, to facilitate their effects or to minimize inappropriate device activation in selected patients. Along with their principal antiarrhythmic effect, AADs may also induce cardiac arrhythmias and the risk for such proarrhythmic effect(s) is particularly increased in patients with reduced left ventricular systolic function or in the setting of electrolyte imbalance. Moreover, CKD itself can induce profound alterations in the pharmacokinetics and pharmacodynamics of many drugs including AADs, thus facilitating the drug accumulation and increased exposure. Hence, the use of AADs in patients with CKD may be challenging. In this review article, we provide an overview of the characteristics of arrhythmogenesis in patients with CKD with special emphasis on the complexity of pharmacokinetics and risk for proarrhythmias when using AADs in patients with cardiac arrhythmias and CKD.

  19. Arrhythmia Management in the Elderly-Implanted Cardioverter Defibrillators and Prevention of Sudden Death.

    PubMed

    Manian, Usha; Gula, Lorne J

    2016-09-01

    We present an overview of arrhythmia management in elderly patients as it pertains to implantable cardioverter defibrillator (ICD) therapy and prevention of sudden death. Treatment of arrhythmia in elderly patients is fraught with challenges pertaining to goals of care and patient frailty. With an ever increasing amount of technology available, realistic expectations of therapy need to balance quality and quantity of life. The ICD is an important treatment option for selected patients at risk of ventricular arrhythmia and sudden cardiac death. However, the incidence of sudden death as a percentage of all-cause mortality decreases with age. Studies have reported that 20% of elderly patients might die within 1 year of an episode of life-threatening ventricular arrhythmia, but most because of nonarrhythmic causes. This illustrates the 'sudden cardiac death paradox,' with a great proportion of death in elderly patients, even those at risk for ventricular arrhythmias, attributable to medical conditions that cannot be addressed by an ICD. We discuss current practices in ICD therapy in elderly patients, existing evidence from registries and clinical trials, approaches to risk stratification, and important ethical considerations. Although the decision on whether ICD insertion is appropriate in the elderly population remains an area of uncertainty from an evidence-based and ethical perspective, we offer insight on potential clinical and research strategies for this growing population.

  20. Detection of atrial arrhythmia for cardiac rhythm management by implantable devices.

    PubMed

    Morris, M M; KenKnight, B H; Lang, D J

    2000-01-01

    Implantable atrial defibrillators (IAD) should provide pacing therapy whenever appropriate (ie, typical atrial flutter) to minimize shock-related patient discomfort. Additionally, IADs should provide diagnostics regarding atrial arrhythmia type and frequency of occurrence to enable improved physician management of atrial arrhythmia. To achieve this, IADs should accurately classify atrial arrhythmia such as atrial fibrillation (AF) and atrial flutter (AFL) This article evaluates the performance of an algorithm, atrial rhythm classification (ARC), designed to classify AF and AFL. The ARC algorithm uses maximum rate, standard deviation, and range of the 12 most recent atrial cycle lengths to plot a point in a three-dimensional space. A decision boundary divides the space into 2 regions--faster/unstable atrial cycle lengths (AF) or slower/stable cycle lengths (AFL). Classifications are made on a sliding window of 12 consecutive cycles until the end of the episode is reached. In this way, continuous episode feedback is provided that can be used to help guide device therapy, measure arrhythmia type and frequency of occurrence. Bipolar (1-cm) electrogram episodes of AF (n = 16) and AFL (n = 7) were acquired from 20 patients and retrospectively analyzed using the ARC algorithm. The sensitivity and specificity in this study was 0.993 and 0.982, respectively. The ARC algorithm would have appropriately guided atrial therapy and minimized discomfort associated with defibrillation shocks in this small patient data set warranting further studies. The ARC algorithm may also be beneficial as a diagnostic tool to assist physician management of atrial arrhythmia.

  1. Postoperative Arrhythmias after Cardiac Surgery: Incidence, Risk Factors, and Therapeutic Management

    PubMed Central

    Cianflone, Domenico

    2014-01-01

    Arrhythmias are a known complication after cardiac surgery and represent a major cause of morbidity, increased length of hospital stay, and economic costs. However, little is known about incidence, risk factors, and treatment of early postoperative arrhythmias. Both tachyarrhythmias and bradyarrhythmias can present in the postoperative period. In this setting, atrial fibrillation is the most common heart rhythm disorder. Postoperative atrial fibrillation is often self-limiting, but it may require anticoagulation therapy and either a rate or rhythm control strategy. However, ventricular arrhythmias and conduction disturbances can also occur. Sustained ventricular arrhythmias in the recovery period after cardiac surgery may warrant acute treatment and long-term preventive strategy in the absence of reversible causes. Transient bradyarrhythmias may be managed with temporary pacing wires placed at surgery, but significant and persistent atrioventricular block or sinus node dysfunction can occur with the need for permanent pacing. We provide a complete and updated review about mechanisms, risk factors, and treatment strategies for the main postoperative arrhythmias. PMID:24511410

  2. Metabolic syndrome remodels electrical activity of the sinoatrial node and produces arrhythmias in rats.

    PubMed

    Albarado-Ibañez, Alondra; Avelino-Cruz, José Everardo; Velasco, Myrian; Torres-Jácome, Julián; Hiriart, Marcia

    2013-01-01

    In the last ten years, the incidences of metabolic syndrome and supraventricular arrhythmias have greatly increased. The metabolic syndrome is a cluster of alterations, which include obesity, hypertension, hypertriglyceridemia, glucose intolerance and insulin resistance, that increase the risk of developing, among others, atrial and nodal arrhythmias. The aim of this study is to demonstrate that metabolic syndrome induces electrical remodeling of the sinus node and produces arrhythmias. We induced metabolic syndrome in 2-month-old male Wistar rats by administering 20% sucrose in the drinking water. Eight weeks later, the rats were anesthetized and the electrocardiogram was recorded, revealing the presence of arrhythmias only in treated rats. Using conventional microelectrode and voltage clamp techniques, we analyzed the electrical activity of the sinoatrial node. We observed that in the sinoatrial node of "metabolic syndrome rats", compared to controls, the spontaneous firing of all cells decreased, while the slope of the diastolic depolarization increased only in latent pacemaker cells. Accordingly, the pacemaker currents If and Ist increased. Furthermore, histological analysis showed a large amount of fat surrounding nodal cardiomyocytes and a rise in the sympathetic innervation. Finally, Poincaré plot denoted irregularity in the R-R and P-P ECG intervals, in agreement with the variability of nodal firing potential recorded in metabolic syndrome rats. We conclude that metabolic syndrome produces a dysfunction SA node by disrupting normal architecture and the electrical activity, which could explain the onset of arrhythmias in rats.

  3. New Analysis of the ν_3 Band of HDCO (monodeuterated Formaldehyde) in the 5.8 μm Region

    NASA Astrophysics Data System (ADS)

    Gomez, L.; Perrin, A.; Mellau, G. C.

    2009-06-01

    Using high-resolution Fourier transform spectra of mono deuterated formaldehyde (HDCO) recorded in the 5.8 μm spectral range at Giessen (Germany), we carried out an extensive analysis of the strong ν_3 fundamental band (carbonyl stretching mode) at 1724.2676 cm^{-1}, starting from results of a previous analysis. For this hybrid band (with both A- and B-type transitions) the analysis was pursued up to high rotational quantum numbers. In this way, it was possible to evidence resonances which perturb the ν_3 lines which are due to the existence of the 2ν_5 (at 2059 cm^{-1}) and ν_5+ν_6 (at 2087 cm^{-1}) dark bands. In addition a local resonance is perturbing the 3^1 levels which is due to a crossing with the 4^1 energy levels. However the 4^1 state is also involved in strong vibration-rotation interactions coupling the {5^1,6^1,4^1} system of resonating states of HDCO J. Mol. Spectrosc. 216, 214 (2002)}. Therefore the final energy levels calculation which was performed for the {5^1,6^1,4^1,3^1,5^2,5^16^1} resonating states accounts for the observed A- type, B- type C-type Coriolis (and/or) Fermi resonances. In this way it was possible to reproduce the observed line positions, within their experimental uncertainties. Finally using a ν_3 band intensity available in the literature we generated, for the first time, a list of line parameters (positions and intensities) for the 5.8 μm band of HDCO. [1] Johns JWC, McKellar ARW., J Mol Spectrosc 1977; 64: 327-339 [2] ν_4, ν_5 and ν_6 correspond to the CHD bending (at 1396 cm^{-1}), the CHD rocking (at 1028 cm^{-1}) and the CHD out of plane (at 1059 cm^{-1}) modes, respectively}. [3] A. Perrin, J. M. Flaud, L. Margulès, J. Demaison, H. Mäder and S. Wörmke, J. Mol. Spectrosc. 216, 214 (2002) [4] Gratien, Nilsson, Doussin, Johnson, Nielsen, Stenstrom and Picquet-Varrault, J. Phys. Chem. 111, 11506 (2007)

  4. Assessment of sediment toxicity in the Lagoon of Venice (Italy) using a multi-species set of bioassays.

    PubMed

    Picone, Marco; Bergamin, Martina; Losso, Chiara; Delaney, Eugenia; Arizzi Novelli, Alessandra; Ghirardini, Annamaria Volpi

    2016-01-01

    Within the framework of a Weight of Evidence (WoE) approach, a set of four toxicity bioassays involving the amphipod Corophium volutator (10 d lethality test on whole sediment), the sea urchin Paracentrotus lividus (fertilization and embryo toxicity tests on elutriate) and the pacific oyster Crassostrea gigas (embryo toxicity test on elutriate) was applied to sediments from 10 sampling sites of the Venice Lagoon (Italy). Sediments were collected during three campaigns carried out in May 2004 (spring campaign), October 2004 (autumn campaign) and February 2005 (winter campaign). Toxicity tests were performed on all sediment samples. Sediment grain-size and chemistry were measured during spring and autumn campaigns. This research investigated (i) the ability of toxicity tests in discriminating among sites with different contamination level, (ii) the occurrence of a gradient of effect among sampling sites, (iii) the possible correlation among toxicity tests, sediment chemistry, grain size and organic carbon, and (iv) the possible occurrence of toxicity seasonal variability. Sediment contamination levels were from low to moderate. No acute toxicity toward amphipods was observed, while sea urchin fertilization was affected only in few sites in just a single campaign. Short-term effects on larval development of sea urchin and oyster evidenced a clear spatial trend among sites, with increasing effects along the axis connecting the sea-inlets with the industrial area. The set of bioassays allowed the identification of a spatial gradient of effect, with decreasing toxicity from the industrial area toward the sea-inlets. Multivariate data analysis showed that the malformations of oyster embryos were significantly correlated to the industrial contamination (metals, polynuclear aromatic hydrocarbons, hexachlorobenzene and polychlorinated biphenyls), while sea urchin development to sediment concentrations of As, Cr and organic carbon. Both embryo toxicity tests were

  5. Monitoring the saltwater intrusion by time lapse electrical resistivity tomography: The Chioggia test site (Venice Lagoon, Italy)

    NASA Astrophysics Data System (ADS)

    de Franco, R.; Biella, G.; Tosi, L.; Teatini, P.; Lozej, A.; Chiozzotto, B.; Giada, M.; Rizzetto, F.; Claude, C.; Mayer, A.; Bassan, V.; Gasparetto-Stori, G.

    2009-12-01

    A novel experiment of time lapse electrical resistivity tomography (TL-ERT) aimed at monitoring the dynamics of the saltwater intrusion in the coastland bounding the southern Venice Lagoon is presented. A dedicated apparatus was developed and operated for about 9 months from November 2005. The system acquired ten resistivity tomograms per day, five of which with high resolution by a 97.5 m long and 2.5 m electrode spacing ERT line, and five by a 300 m long and 5 m electrode spacing line down to 50-60 m depth. The stratigraphy of a 50 m deep borehole drilled in the nearby of the ERT-TL alignment outlines the presence of a shallow phreatic aquifer in the shallower 12 m thick unit, followed by a semi-confined aquifer between 18 and 38 m depth and a locally confined aquifer down to the bottom. The shallow aquifer is the most contaminated by the salt intrusion with a minimum value of the formation resistivity equal to 1.0 ohm m corresponding to a salinity of 25-30 gr/l. A seasonal resistivity fluctuation is observed, with the saltwater front that intrudes landward during the autumn-winter season and moves back seaward in spring-summer. The first semi-confined aquifer is characterized by resistivity value of about 5 ohm m, while the confined aquifer is less contaminated showing resistivity values greater than 7.5 ohm m. For both the two confined aquifers the resistivity value rises at the beginning of the summer probably due to the seasonal fresh water recharge supplied regionally from the mainland. The TL-ERT data have been correlated with a number of environmental variables. A relationship is found between the resistivity in the upper 3-4 m of the phreatic aquifer and the rainfalls, and between the water level in the adjacent main channel and the resistivity down to about 10 m depth. With respect to the tidal regime, a daily/weekly correlation with resistivity changes is not evidenced, while a significant negative correlation coefficient exists at monthly to seasonal

  6. Convective and global stability analysis of a Mach 5.8 boundary layer grazing a compliant surface

    NASA Astrophysics Data System (ADS)

    Dettenrieder, Fabian; Bodony, Daniel

    2016-11-01

    Boundary layer transition on high-speed vehicles is expected to be affected by unsteady surface compliance. The stability properties of a Mach 5.8 zero-pressure-gradient laminar boundary layer grazing a nominally-flat thermo-mechanically compliant panel is considered. The linearized compressible Navier-Stokes equations describe small amplitude disturbances in the fluid while the panel deformations are described by the Kirchhoff-Love plate equation and its thermal state by the transient heat equation. Compatibility conditions that couple disturbances in the fluid to those in the solid yield simple algebraic and robin boundary conditions for the velocity and thermal states, respectively. A local convective stability analysis shows that the panel can modify both the first and second Mack modes when, for metallic-like panels, the panel thickness exceeds the lengthscale δ99 Rex- 0 . 5 . A global stability analysis, which permits finite panel lengths with clamped-clamped boundary conditions, shows a rich eigenvalue spectrum with several branches. Unstable modes are found with streamwise-growing panel deformations leading to Mach wave-type radiation. Stable global modes are also found and have distinctly different panel modes but similar radiation patterns. Air Force Office of Scientific Research.

  7. Mutant GDF5 enhances ameloblast differentiation via accelerated BMP2-induced Smad1/5/8 phosphorylation

    PubMed Central

    Liu, Jia; Saito, Kan; Maruya, Yuriko; Nakamura, Takashi; Yamada, Aya; Fukumoto, Emiko; Ishikawa, Momoko; Iwamoto, Tsutomu; Miyazaki, Kanako; Yoshizaki, Keigo; Ge, Lihong; Fukumoto, Satoshi

    2016-01-01

    Bone morphogenetic proteins (BMPs) regulate hard tissue formation, including bone and tooth. Growth differentiation factor 5 (GDF5), a known BMP, is expressed in cartilage and regulates chondrogenesis, and mutations have been shown to cause osteoarthritis. Notably, GDF5 is also expressed in periodontal ligament tissue; however, its role during tooth development is unclear. Here, we used cell culture and in vivo analyses to determine the role of GDF5 during tooth development. GDF5 and its associated BMP receptors are expressed at the protein and mRNA levels during postnatal tooth development, particularly at a stage associated with enamel formation. Furthermore, whereas BMP2 was observed to induce evidently the differentiation of enamel-forming ameloblasts, excess GDF5 induce mildly this differentiation. A mouse model harbouring a mutation in GDF5 (W408R) showed enhanced enamel formation in both the incisors and molars, but not in the tooth roots. Overexpression of the W408R GDF5 mutant protein was shown to induce BMP2-mediated mRNA expression of enamel matrix proteins and downstream phosphorylation of Smad1/5/8. These results suggest that mutant GDF5 enhances ameloblast differentiation via accelerated BMP2-signalling. PMID:27030100

  8. Right Ventricular Outflow Tract Arrhythmias: Benign Or Early Stage Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia?

    PubMed

    Lin Md, Tina; Conti Md, Sergio; Cipolletta Md, Laura; Marino Md, Vittoria; Zucchetti Md, Martina; Russo Md, Eleonora; Pizzamiglio Md, Francesca; Al-Mohani Md, Ghaliah; Pala Be, Salvatore; Catto Be PhD, Valentina; Di Biase Md PhD, Luigi; Natale Md, Andrea; Tondo Md PhD Fesc, Claudio; Carbucicchio Md, Corrado

    2014-12-01

    Ventricular arrhythmias (VAs) arising from the right ventricular outflow tract (RVOT) are a common and heterogeneous entity. Idiopathic right ventricular arrhythmias (IdioVAs) are generally benign, with excellent ablation outcomes and long-term arrhythmia-free survival, and must be distinguished from other conditions associated with VAs arising from the right ventricle: the differential diagnosis with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is therefore crucial because VAs are one of the most important causes of sudden cardiac death (SCD) in young individuals even with early stage of the disease. Radiofrequency catheter ablation (RFCA) is a current option for the treatment of VAs but important differences must be considered in terms of indication, purposes and procedural strategies in the treatment of the two conditions. In this review, we comprehensively discuss clinical and electrophysiological features, diagnostic and therapeutic techniques in a compared analysis of these two entities.

  9. Ubiquitous health monitoring and real-time cardiac arrhythmias detection: a case study.

    PubMed

    Li, Jian; Zhou, Haiying; Zuo, Decheng; Hou, Kun-Mean; De Vaulx, Christophe

    2014-01-01

    As the symptoms and signs of heart diseases that cause sudden cardiac death, cardiac arrhythmia has attracted great attention. Due to limitations in time and space, traditional approaches to cardiac arrhythmias detection fail to provide a real-time continuous monitoring and testing service applicable in different environmental conditions. Integrated with the latest technologies in ECG (electrocardiograph) analysis and medical care, the pervasive computing technology makes possible the ubiquitous cardiac care services, and thus brings about new technical challenges, especially in the formation of cardiac care architecture and realization of the real-time automatic ECG detection algorithm dedicated to care devices. In this paper, a ubiquitous cardiac care prototype system is presented with its architecture framework well elaborated. This prototype system has been tested and evaluated in all the clinical-/home-/outdoor-care modes with a satisfactory performance in providing real-time continuous cardiac arrhythmias monitoring service unlimitedly adaptable in time and space.

  10. Method and apparatus for the guided ablative therapy of fast ventricular arrhythmia

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J. (Inventor); Barley, Maya (Inventor)

    2010-01-01

    Method and apparatus for guiding ablative therapy of abnormal biological electrical excitation. The excitation from the previous excitatory wave is significant at the beginning of the next excitation. In particular, it is designed for treatment of fast cardiac arrhythmias. Electrical signals are acquired from recording electrodes, and an inverse dipole method is used to identify the site of origin of an arrhythmia. The location of the tip of an ablation catheter is similarly localized from signals acquired from the recording electrodes while electrical pacing energy is delivered to the tip of the catheter close to or in contact with the cardiac tissue. The catheter tip is then guided to the site of origin of the arrhythmia, and ablative radio frequency energy is delivered to its tip to ablate the site.

  11. Calcium and voltage imaging in arrhythmia models by high-speed microscopy

    NASA Astrophysics Data System (ADS)

    de Mauro, C.; Cecchetti, C. A.; Alfieri, D.; Borile, G.; Urbani, A.; Mongillo, M.; Pavone, F. S.

    2014-03-01

    Alterations in intracellular cardiomyocyte calcium handling have a key role in initiating and sustaining arrhythmias. Arrhythmogenic calcium leak from sarcoplasmic reticulum (SR) can be attributed to all means by which calcium exits the SR store in an abnormal fashion. Abnormal SR calcium exit maymanifest as intracellular Ca2+ sparks and/or Ca2+ waves. Ca2+ signaling in arrhythmogenesis has been mainly studied in isolated cardiomyocytes and given that the extracellular matrix influences both Ca2+ and membrane potential dynamics in the intact heart and underlies environmentally mediated changes, understanding how Ca2+ and voltage are regulated in the intact heart will represent a tremendous advancement in the understanding of arrhythmogenic mechanisms. Using novel high-speed multiphoton microscopy techinques, such as multispot and random access, we investigated animal models with inherited and acquired arrhythmias to assess the role of Ca2+ and voltage signals as arrhythmia triggers in cell and subcellular components of the intact heart and correlate these with electrophysiology.

  12. Macrophage-dependent IL-1β production induces cardiac arrhythmias in diabetic mice

    PubMed Central

    Monnerat, Gustavo; Alarcón, Micaela L.; Vasconcellos, Luiz R.; Hochman-Mendez, Camila; Brasil, Guilherme; Bassani, Rosana A.; Casis, Oscar; Malan, Daniela; Travassos, Leonardo H.; Sepúlveda, Marisa; Burgos, Juan Ignacio; Vila-Petroff, Martin; Dutra, Fabiano F.; Bozza, Marcelo T.; Paiva, Claudia N.; Carvalho, Adriana Bastos; Bonomo, Adriana; Fleischmann, Bernd K.; de Carvalho, Antonio Carlos Campos; Medei, Emiliano

    2016-01-01

    Diabetes mellitus (DM) encompasses a multitude of secondary disorders, including heart disease. One of the most frequent and potentially life threatening disorders of DM-induced heart disease is ventricular tachycardia (VT). Here we show that toll-like receptor 2 (TLR2) and NLRP3 inflammasome activation in cardiac macrophages mediate the production of IL-1β in DM mice. IL-1β causes prolongation of the action potential duration, induces a decrease in potassium current and an increase in calcium sparks in cardiomyocytes, which are changes that underlie arrhythmia propensity. IL-1β-induced spontaneous contractile events are associated with CaMKII oxidation and phosphorylation. We further show that DM-induced arrhythmias can be successfully treated by inhibiting the IL-1β axis with either IL-1 receptor antagonist or by inhibiting the NLRP3 inflammasome. Our results establish IL-1β as an inflammatory connection between metabolic dysfunction and arrhythmias in DM. PMID:27882934

  13. Light-based Approaches to Cardiac Arrhythmia Research: From Basic Science to Translational Applications

    PubMed Central

    Karathanos, Thomas V.; Boyle, Patrick M.; Trayanova, Natalia A.

    2016-01-01

    Light has long been used to image the heart, but now it can be used to modulate its electrophysiological function. Imaging modalities and techniques have long constituted an indispensable part of arrhythmia research and treatment. Recently, advances in the fields of optogenetics and photodynamic therapy have provided scientists with more effective approaches for probing, studying and potentially devising new treatments for cardiac arrhythmias. This article is a review of research toward the application of these techniques. It contains (a) an overview of advancements in technology and research that have contributed to light-based cardiac applications and (b) a summary of current and potential future applications of light-based control of cardiac cells, including modulation of heart rhythm, manipulation of cardiac action potential morphology, quantitative analysis of arrhythmias, defibrillation and cardiac ablation. PMID:27840581

  14. Carbon Monoxide Induces Cardiac Arrhythmia via Induction of the Late Na+ Current

    PubMed Central

    Dallas, Mark L.; Yang, Zhaokang; Boyle, John P.; Boycott, Hannah E.; Scragg, Jason L.; Milligan, Carol J.; Elies, Jacobo; Duke, Adrian; Thireau, Jérôme; Reboul, Cyril; Richard, Sylvain; Bernus, Olivier; Steele, Derek S.

    2012-01-01

    Rationale: Clinical reports describe life-threatening cardiac arrhythmias after environmental exposure to carbon monoxide (CO) or accidental CO poisoning. Numerous case studies describe disruption of repolarization and prolongation of the QT interval, yet the mechanisms underlying CO-induced arrhythmias are unknown. Objectives: To understand the cellular basis of CO-induced arrhythmias and to indentify an effective therapeutic approach. Methods: Patch-clamp electrophysiology and confocal Ca2+ and nitric oxide (NO) imaging in isolated ventricular myocytes was performed together with protein S-nitrosylation to investigate the effects of CO at the cellular and molecular levels, whereas telemetry was used to investigate effects of CO on electrocardiogram recordings in vivo. Measurements and Main Results: CO increased the sustained (late) component of the inward Na+ current, resulting in prolongation of the action potential and the associated intracellular Ca2+ transient. In more than 50% of myocytes these changes progressed to early after-depolarization–like arrhythmias. CO elevated NO levels in myocytes and caused S-nitrosylation of the Na+ channel, Nav1.5. All proarrhythmic effects of CO were abolished by the NO synthase inhibitor l-NAME, and reversed by ranolazine, an inhibitor of the late Na+ current. Ranolazine also corrected QT variability and arrhythmias induced by CO in vivo, as monitored by telemetry. Conclusions: Our data indicate that the proarrhythmic effects of CO arise from activation of NO synthase, leading to NO-mediated nitrosylation of NaV1.5 and to induction of the late Na+ current. We also show that the antianginal drug ranolazine can abolish CO-induced early after-depolarizations, highlighting a novel approach to the treatment of CO-induced arrhythmias. PMID:22822026

  15. 3D X-ray imaging methods in support catheter ablations of cardiac arrhythmias.

    PubMed

    Stárek, Zdeněk; Lehar, František; Jež, Jiří; Wolf, Jiří; Novák, Miroslav

    2014-10-01

    Cardiac arrhythmias are a very frequent illness. Pharmacotherapy is not very effective in persistent arrhythmias and brings along a number of risks. Catheter ablation has became an effective and curative treatment method over the past 20 years. To support complex arrhythmia ablations, the 3D X-ray cardiac cavities imaging is used, most frequently the 3D reconstruction of CT images. The 3D cardiac rotational angiography (3DRA) represents a modern method enabling to create CT like 3D images on a standard X-ray machine equipped with special software. Its advantage lies in the possibility to obtain images during the procedure, decreased radiation dose and reduction of amount of the contrast agent. The left atrium model is the one most frequently used for complex atrial arrhythmia ablations, particularly for atrial fibrillation. CT data allow for creation and segmentation of 3D models of all cardiac cavities. Recently, a research has been made proving the use of 3DRA to create 3D models of other cardiac (right ventricle, left ventricle, aorta) and non-cardiac structures (oesophagus). They can be used during catheter ablation of complex arrhythmias to improve orientation during the construction of 3D electroanatomic maps, directly fused with 3D electroanatomic systems and/or fused with fluoroscopy. An intensive development in the 3D model creation and use has taken place over the past years and they became routinely used during catheter ablations of arrhythmias, mainly atrial fibrillation ablation procedures. Further development may be anticipated in the future in both the creation and use of these models.

  16. Risk of Ventricular Arrhythmia with Citalopram and Escitalopram: A Population-Based Study

    PubMed Central

    Qirjazi, Elena; McArthur, Eric; Nash, Danielle M.; Dixon, Stephanie N.; Weir, Matthew A.; Vasudev, Akshya; Jandoc, Racquel; Gula, Lorne J.; Oliver, Matthew J.; Wald, Ron; Garg, Amit X.

    2016-01-01

    Background The risk of ventricular arrhythmia with citalopram and escitalopram is controversial. In this study we investigated the association between these two drugs and the risk of ventricular arrhythmia. Methods We conducted a population-based retrospective cohort study of older adults (mean age 76 years) from 2002 to 2012 in Ontario, Canada, newly prescribed citalopram (n = 137 701) or escitalopram (n = 38 436), compared to those prescribed referent antidepressants sertraline or paroxetine (n = 96 620). After inverse probability of treatment weighting using a propensity score, the baseline characteristics of the comparison groups were similar. The primary outcome was a hospital encounter with ventricular arrhythmia within 90 days of a new prescription, assessed using hospital diagnostic codes. The secondary outcome was all-cause mortality within 90 days. Results Citalopram was associated with a higher risk of a hospital encounter with ventricular arrhythmia compared with referent antidepressants (0.06% vs. 0.04%, relative risk [RR] 1.53, 95% confidence intervals [CI]1.03 to 2.29), and a higher risk of mortality (3.49% vs. 3.12%, RR 1.12, 95% CI 1.06 to 1.18). Escitalopram was not associated with a higher risk of ventricular arrhythmia compared with the referent antidepressants (0.03% vs. 0.04%, RR 0.84, 95% CI 0.42 to 1.68), but was associated with a higher risk of mortality (2.86% vs. 2.63%, RR 1.09, 95% CI 1.01 to 1.18). Conclusion Among older adults, initiation of citalopram compared to two referent antidepressants was associated with a small but statistically significant increase in the 90-day risk of a hospital encounter for ventricular arrhythmia. PMID:27513855

  17. Arrhythmia recognition and classification using combined linear and nonlinear features of ECG signals.

    PubMed

    Elhaj, Fatin A; Salim, Naomie; Harris, Arief R; Swee, Tan Tian; Ahmed, Taqwa

    2016-04-01

    Arrhythmia is a cardiac condition caused by abnormal electrical activity of the heart, and an electrocardiogram (ECG) is the non-invasive method used to detect arrhythmias or heart abnormalities. Due to the presence of noise, the non-stationary nature of the ECG signal (i.e. the changing morphology of the ECG signal with respect to time) and the irregularity of the heartbeat, physicians face difficulties in the diagnosis of arrhythmias. The computer-aided analysis of ECG results assists physicians to detect cardiovascular diseases. The development of many existing arrhythmia systems has depended on the findings from linear experiments on ECG data which achieve high performance on noise-free data. However, nonlinear experiments characterize the ECG signal more effectively sense, extract hidden information in the ECG signal, and achieve good performance under noisy conditions. This paper investigates the representation ability of linear and nonlinear features and proposes a combination of such features in order to improve the classification of ECG data. In this study, five types of beat classes of arrhythmia as recommended by the Association for Advancement of Medical Instrumentation are analyzed: non-ectopic beats (N), supra-ventricular ectopic beats (S), ventricular ectopic beats (V), fusion beats (F) and unclassifiable and paced beats (U). The characterization ability of nonlinear features such as high order statistics and cumulants and nonlinear feature reduction methods such as independent component analysis are combined with linear features, namely, the principal component analysis of discrete wavelet transform coefficients. The features are tested for their ability to differentiate different classes of data using different classifiers, namely, the support vector machine and neural network methods with tenfold cross-validation. Our proposed method is able to classify the N, S, V, F and U arrhythmia classes with high accuracy (98.91%) using a combined support

  18. Prevention and management of perioperative arrhythmias in the thoracic surgical population.

    PubMed

    Amar, David

    2008-06-01

    Although bradyarrhythmias or malignant ventricular tachyarrhythmias have been reported in less than 1% of patients following noncardiac surgery, rapid atrial arrhythmias more frequently affect the elderly who undergo thoracic operations. This article focuses on new issues leading to the improved understanding of the pathophysiology and mechanisms of postoperative atrial arrhythmias. It discusses new risk factors and a prediction rule for postthoracotomy atrial fibrillation (AF), reviews prophylaxis and acute therapeutic interventions for postthoracotomy AF, and highlights the most recent recommendations of the American Heart Association Task Force on the management of patients who have AF with emphasis on preventing thromboembolic events.

  19. The role of viruses, inflammation and myocardial macrophages in the development of idiopathic arrhythmia

    NASA Astrophysics Data System (ADS)

    Rebenkova, M.; Gombozhapova, A.; Shurupov, V.; Rogovskaya, Yu.; Botalov, R.; Ryabov, V.; Popov, S.; Karpov, R.

    2015-11-01

    We studied viral antigens, inflammation, and macrophages in the endomyocardial biopsies of patients with idiopathic arrhythmias. Immunohistological study was performed to identify the antigens of cardiotropic viruses and the types of lymphocytes and macrophages. We observed the presence of viral antigens in the myocardium of patients with and without histological criteria of myocarditis. Heart failure and ventricular arrhythmias were associated with small focal infiltration of the myocardium with macrophages. The presence of viral antigens in the myocardium was associated with fewer number of myocardial M2 macrophages. Severity of myocardial interstitial fibrosis correlated with small-focal infiltration of M2 macrophages.

  20. Non-Invasive Assessment of Susceptibility to Ventricular Arrhythmias During Simulated Microgravity

    NASA Technical Reports Server (NTRS)

    Cohen, Richard J.

    1999-01-01

    The Cardiovascular Alterations Team is currently conducting studies to determine what alterations in hemodynamic regulation result from sixteen days of simulated microgravity exposure in normal human subjects. In this project we make additional measurements on these same study subjects in order to determine whether there is an increase in susceptibility to ventricular arrhythmias resulting from simulated microgravity exposure. Numerous anecdotal and documented reports from the past 30 years suggest that the incidence of ventricular arrhythmias among astronauts is increased during space flight. For example, documented runs of ventricular tachycardia have been recorded from crew members of Skylab and Mir, there was much attention given by the lay press to Mir Commander Vasily Tslbliyev's complaints of heart rhythm irregularities in July of 1997, and cardiovascular mechanisms may have been causal in the recent death of an experimental primate shortly after return from space. In 1986, a Mir cosmonaut, Alexander Laveikin, was brought home and replaced with an alternate cosmonaut as a result of cardiac dysrhythmias that began during extravehicular activity. Furthermore, at a joint NASA/NSBRI workshop held in January 1998, cardiac arrhythmias were identified as the highest priority cardiovascular risk to a human Mars mission. Despite the evidence for the risk of a potentially lethal arrhythmia resulting from microgravity exposure, the effects of space flight and the associated physiologic stresses on cardiac conduction processes are not known, and an increase in cardiac susceptibility to arrhythmias has never been quantified. In this project, we are determining whether simulated space flight increases the risk of developing life-threatening heart rhythm disturbances such as sustained ventricular tachycardia (defined as ventricular tachycardia lasting at least 30 seconds or resulting in hemodynamic collapse) and ventricular fibrillation. We are obtaining measures of

  1. Immediate effect on cardiac output of reversion to sinus rhythm from rapid arrhythmias.

    PubMed

    Wright, J S; Fabian, J; Epstein, E J

    1970-08-08

    Cardiac output was estimated immediately before and after conversion to sinus rhythm in nine patients with rapid arrhythmias. Conversion was by synchronized direct-current shock in eight patients, and by direct atrial wall stimulation in the other. In seven patients there was an immediate increase in cardiac output after restoration of sinus rhythm. The percentage increase in output was directly proportional to the rate of the arrhythmia immediately before conversion (r=0.91, P<0.01). The critical heart rate, above which an immediate increase in cardiac output might be expected on conversion to sinus rhythm, appeared in these patients to be about 160 beats per minute.

  2. GPU based cloud system for high-performance arrhythmia detection with parallel k-NN algorithm.

    PubMed

    Tae Joon Jun; Hyun Ji Park; Hyuk Yoo; Young-Hak Kim; Daeyoung Kim

    2016-08-01

    In this paper, we propose an GPU based Cloud system for high-performance arrhythmia detection. Pan-Tompkins algorithm is used for QRS detection and we optimized beat classification algorithm with K-Nearest Neighbor (K-NN). To support high performance beat classification on the system, we parallelized beat classification algorithm with CUDA to execute the algorithm on virtualized GPU devices on the Cloud system. MIT-BIH Arrhythmia database is used for validation of the algorithm. The system achieved about 93.5% of detection rate which is comparable to previous researches while our algorithm shows 2.5 times faster execution time compared to CPU only detection algorithm.

  3. Mechanisms and clinical significance of early recurrences of atrial arrhythmias after catheter ablation for atrial fibrillation

    PubMed Central

    Liang, Jackson J; Dixit, Sanjay; Santangeli, Pasquale

    2016-01-01

    Early recurrence of atrial arrhythmias (ERAA) after ablation is common and strongly predicts late recurrences and ablation failure. However, since arrhythmia may eventually resolve in up to half of patients with ERAA, guidelines do not recommend immediate reintervention for ERAA episodes occurring during a 3-mo post-ablation blanking period. Certain clinical demographic, electrophysiologic, procedural, and ERAA-related characteristics may predict a higher likelihood of long-term ablation failure. In this review, we aim to discuss potential mechanisms of ERAA, and to summarize the clinical significance, prognostic implications, and treatment options for ERAA. PMID:27957250

  4. Ventricular arrhythmias induced by long-term use of ephedrine in two competitive athletes.

    PubMed

    Casella, Michela; Dello Russo, Antonio; Izzo, Gennaro; Pieroni, Maurizio; Andreini, Daniele; Russo, Eleonora; Colombo, Daniele; Bologna, Fabrizio; Bolognese, Leonardo; Zeppilli, Paolo; Tondo, Claudio

    2015-03-01

    Ephedrine is a sympathomimetic substance used by sportsmen as a doping substance because of its stimulating and slimming effects. We report two cases of ventricular arrhythmias induced by abuse of ephedrine in two competitive athletes. Endomyocardial biopsies guided by electroanatomic mapping revealed contraction-band necrosis, a myocardial injury frequently observed in cases of catecholamine excess. Our cases suggest that long-term abuse of ephedrine may result in myocardial damage, and that these structural alterations may promote areas of slow conduction favoring re-entrant ventricular tachyarrhythmias and a long-lasting risk of ventricular arrhythmias.

  5. [The anti-arrhythmia action of an extract of Rhodiola rosea and of n-tyrosol in models of experimental arrhythmias].

    PubMed

    Maĭmeskulova, L A; Maslov, L N

    1998-01-01

    A daily 8-day course of Rhodiolae fluidum extract (1 ml/kg; ED50 = 0.43 ml/kg)--a preparation from the group of adaptogens caused a marked preventive antiarrhythmic effect on models of adrenaline and CaCl2-induced, but not acontine, arrhythmias. Aglycone--n-tyrosol demonstrated a lower antiarrhythmic activity (ED50 = 16 mg/kg) than that of Rhodiola extract.

  6. Reduced 4,5',8-trimethylpsoralen cross-linking of left-handed Z-DNA stabilized by DNA supercoiling

    SciTech Connect

    Sinden, R.R.; Kochel, T.J.

    1987-03-10

    Z-DNA-forming sequences, (GT)/sub 21/, (GT)/sub 12/ATGT, and (CG)/sub 6/TA(CG)/sub 6/, were cloned into plasmids. These sequences formed left-handed Z-DNA conformations under torsional tension from negative supercoiling of DNA. (/sup 3/H)4,5',8-Trimethylpsoralen, on absorption of 360-nm light, forms monoadducts and interstrand cross-links in DNA that exists in the B-helical conformation. Trimethylpsoralen cross-links were introduced into the potential Z-DNA-forming sequences in relaxed DNA when these sequences existed as B-form DNA. In supercoiled DNA when these sequences existed in the Z conformation, the rate of cross-linking was greatly reduced, and trimethylpsoralen did not form monoadducts appreciably to Z-DNA. As an internal control in these experiments, the rates of cross-linking of the Z-DNA-forming sequences were measured relative to that of an adjacent, cloned sequence that could not adopt a Z conformation. The initial relative rates of cross-linking to Z-DNA-forming sequences were dependent on the superhelical density of the DNA, and the rates were ultimately reduced by factors of 10-15 for Z-DNA in highly supercoiled plasmids. This differential rate of cross-linking provides a novel assay for Z-DNA. Initial application of this assay in vivo suggests that a substantial fraction of (CG)/sub 6/TA(CG)/sub 6/, which existed as Z-DNA in plasmid molecules purified from cells, existed in the B conformation in vivo.

  7. The Association between Arrhythmia and Helicobacter pylori Infection: A Meta-Analysis of Case-Control Studies

    PubMed Central

    Yan, Jin; She, Qiang; Zhang, Yifeng; Cui, Chang; Zhang, Guoxin

    2016-01-01

    Arrhythmia is a common disease around the world and Helicobacter pylori (H. pylori) is a bacterium infecting 28% to 84% of subjects, depending on the population tested. However, the implication of H. pylori in cardiac arrhythmia is poorly understood. We performed this meta-analysis with an aim to identify the association between arrhythmia and H. pylori. We searched PubMed, Embase, Web of Science, and the Cochrane library databases to select studies on the association between arrhythmia and H. pylori. In the arrhythmia group, 392 (58.1%) were H. pylori-positive and in the control group 640 (47.8%) were H. pylori-positive. Compared to the controls, the infection rate of H. pylori was higher in patients with arrhythmia than in controls (odds ratio (OR) = 1.797, 95% confidence interval (CI): 1.081–2.988, p < 0.05). Subgroup analysis indicated that H. pylori infection was a risk factor for atrial fibrillation in Asia and Africa. Therefore, a correlation between H. pylori infection and arrhythmia may exist and H. pylori eradication may decrease the occurrence of arrhythmia, especially in Asia and Africa. PMID:27854353

  8. The Association between Arrhythmia and Helicobacter pylori Infection: A Meta-Analysis of Case-Control Studies.

    PubMed

    Yan, Jin; She, Qiang; Zhang, Yifeng; Cui, Chang; Zhang, Guoxin

    2016-11-16

    Arrhythmia is a common disease around the world and Helicobacter pylori (H. pylori) is a bacterium infecting 28% to 84% of subjects, depending on the population tested. However, the implication of H. pylori in cardiac arrhythmia is poorly understood. We performed this meta-analysis with an aim to identify the association between arrhythmia and H. pylori. We searched PubMed, Embase, Web of Science, and the Cochrane library databases to select studies on the association between arrhythmia and H. pylori. In the arrhythmia group, 392 (58.1%) were H. pylori-positive and in the control group 640 (47.8%) were H. pylori-positive. Compared to the controls, the infection rate of H. pylori was higher in patients with arrhythmia than in controls (odds ratio (OR) = 1.797, 95% confidence interval (CI): 1.081-2.988, p < 0.05). Subgroup analysis indicated that H. pylori infection was a risk factor for atrial fibrillation in Asia and Africa. Therefore, a correlation between H. pylori infection and arrhythmia may exist and H. pylori eradication may decrease the occurrence of arrhythmia, especially in Asia and Africa.

  9. Relationship of ventricular arrhythmias to the angiographically and scintigraphically estimated extent of ventricular damage late after myocardial infarction

    SciTech Connect

    Huikuri, H.V.; Korhonen, U.R.; Linnaluoto, M.K.; Takkunen, J.T.

    1987-03-01

    In order to study the quantitative relationship of ventricular arrhythmias to myocardial damage and ischemia, 61 patients with a previous myocardial infarction (at least 6 months previously) were studied by 24-hour ambulatory ECG monitoring, cardiac catheterization, and thallium-201 scintigraphy. Thirty-five patients (57%) had no ectopic beats or only infrequent, unifocal ones and 26 patients (43%) had complex ventricular arrhythmias. Left ventricular function was lower in the latter, but the number of diseased vessels did not differ in the two groups. The reduction of thallium activity in the infarct area was more marked in patients with complex arrhythmias. Multiple thallium defects were not more common in arrhythmia patients, however. These data support the view that complex ventricular arrhythmias are more closely related to the severity of ventricular damage than the presence of myocardial ischemia remote to the area of previous infarction.

  10. [Analysis of the sequences of internal transcribed spacers ITS1, ITS2 and the 5.8S ribosomal gene of species of the Amaranthus genus].

    PubMed

    Slugina, M A; Torres Minho, K; Filiushin, M A

    2014-01-01

    Analysis of the sequence ITS1-5.8S-ITS2 in 11 samples of the amaranth species (Amaranthus caudatus, A. cruentus, A. hybridus, A. tricolor, A. paniculatus, A. hypohondriacus) was performed. It has been shown that the variability of the sequences of the intergenic spacers ITS1, ITS2 and 5.8S rRNA gene of the amaranth species analyzed is extremely low. A possible secondary structure of the 5.8S rRNA molecule was determined for the first time; three conservative motifs were identified. A single nucleotide substitution found in A. hybridus did not change the loop topology. In the sample of Celosia cristata taken as an external group, a four-nucleotide insertion in the 5'-end of the gene and a one-nucleotide deletion in the fourth hairpin not affecting the general topology of the 5.8S rRNA molecule were found.

  11. Icariin regulates systemic iron metabolism by increasing hepatic hepcidin expression through Stat3 and Smad1/5/8 signaling.

    PubMed

    Zhang, Miao; Liu, Jing; Guo, Wenli; Liu, Xin; Liu, Sijin; Yin, Huijun

    2016-05-01

    Systemic iron homeostasis is strictly controlled under normal conditions to ensure a balance between the absorption, utilization, storage and recycling of iron. The hepcidin-ferroportin (FPN) axis is of critical importance in the maintenance of iron homeostasis. Hepcidin deficiency gives rise to enhanced dietary iron absorption, as well as to increased iron release from macrophages, and this in turn results in iron accumulation in the plasma and organs, and is associated with a range of tissue pathologies. Low hepcidin levels have been demonstrated in most forms of hereditary hemochromatosis (HH), as well as in β-thalassemia. Therapies that increase hepcidin concentrations may potentially play a role in the treatment of these iron overload-related diseases. To date, natural compounds have not been extensively investigated for this purpose, to the best of our knowledge. Thus, in the present study, we screened natural compounds that have the potential to regulate hepcidin expression. By performing hepcidin promoter-luciferase assay, RT-qPCR and animal experiments, we demonstrated that icariin and berberine were potent stimulators of hepcidin transcription. Mechanistic experiments indicated that icariin and berberine increased hepcidin expression by activating the signal transducer and activator of transcription 3 (Stat3) and Smad1/5/8 signaling pathways. The induction of hepcidin was confirmed in mice following icariin administration, coupled with associated changes in serum and tissue iron concentrations. In support of these findings, the icariin analogues, epimedin A, B and C, also increased hepatic hepcidin expression. However, these changes were not observed in hepcidin-deficient [Hamp1-/- or Hamp1‑knockout (KO)] mice following icariin administration, thereby verifying hepatic hepcidin as the target of icariin. Although berberine exhibited a robust capacity to promote hepcidin expression in vitro, it failed to alter hepcidin expression in mice. Taken together

  12. Phylogenetic relationships in genus Arachis based on ITS and 5.8S rDNA sequences

    PubMed Central

    2010-01-01

    Background The genus Arachis comprises 80 species and it is subdivided into nine taxonomic sections (Arachis, Caulorrhizae, Erectoides, Extranervosae, Heteranthae, Procumbentes, Rhizomatosae, Trierectoides, and Triseminatae). This genus is naturally confined to South America and most of its species are native to Brazil. In order to provide a better understanding of the evolution of the genus, we reconstructed the phylogeny of 45 species using the variation observed on nucleotide sequences in internal transcribed spacer regions (ITS1 and ITS2) and 5.8 S of nuclear ribosomal DNA. Results Intraspecific variation was detected, but in general it was not enough to place accessions of the same species in different clades. Our data support the view that Arachis is a monophyletic group and suggested Heteranthae as the most primitive section of genus Arachis. The results confirmed the circumscriptions of some sections (Caulorrhizae, Extranervosae), but raised questions about others. Sections Erectoides, Trierectoides and Procumbentes were not well defined, while sections Arachis and Rhizomatosae seem to include species that could be moved to different sections. The division of section Arachis into A and B genome species was also observed in the phylogenetic tree and these two groups of species may not have a monophyletic origin. The 2n = 2x = 18 species of section Arachis (A. praecox, A. palustris and A. decora) were all placed in the same clade, indicating they are closely related to each other, and their genomes are more related to B genome than to the A genome. Data also allowed insights on the origin of tetraploid A. glabrata, suggesting rhizome appeared twice within the genus and raising questions about the placement of that species in section Rhizomatosae. Conclusion The main clades established in this study in general agreed with many other studies that have used other types of evidences and sets of species, being some of them included in our study and some not. Thus

  13. Anti-proliferative actions of 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone in vascular smooth muscle cells

    SciTech Connect

    Lee, Jung-Jin; Zhang, Wei-Yun; Yi, Hyoseok; Kim, Yohan; Kim, In-Su; Shen, Gui-Nan; Song, Gyu-Yong; Myung, Chang-Seon

    2011-07-22

    Highlights: {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced VSMC proliferation in a dose-dependent manner with no apparent cytotoxicity. {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced phosphorylation of Erk1/2 and PLC{gamma}1. {yields} 2-Decylamino-DMNQ arrested a G{sub 0}/G{sub 1} cell cycle progression in association with pRb phosphorylation and PCNA expression. {yields} Both U0126, an Erk inhibitor, and U73122, a PLC{gamma} inhibitor, arrested a G{sub 0}/G{sub 1} phase of the cell cycle. -- Abstract: Naphthoquinone derivatives have been reported to possess various pharmacological activities, such as antiplatelet, anticancer, antifungal, and antiviral properties. In this study, we investigated the effects of a newly-synthesized naphthoquinone derivative, 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone (2-decylamino-DMNQ), on VSMC proliferation and examined the molecular basis of the underlying mechanism. In a dose-dependent manner, 2-decylamino-DMNQ inhibited PDGF-stimulated VSMC proliferation with no apparent cytotoxic effect. While 2-decylamino-DMNQ did not affect PDGF-R{beta} or Akt, it did inhibit the phosphorylation of Erk1/2 and PLC{gamma}1 induced by PDGF. Moreover, 2-decylamino-DMNQ suppressed DNA synthesis through the arrest of cell cycle progression at the G{sub 0}/G{sub 1} phase, including the suppression of pRb phosphorylation and a decrease in PCNA expression, which was related to the downregulation of cell cycle regulatory factors, such as cyclin D1/E and CDK 2/4. It was demonstrated that both U0126, an Erk1/2 inhibitor, and U73122, a PLC{gamma} inhibitor, increased the proportion of cells in the G{sub 0}/G{sub 1} phase of the cell cycle. Thus, these results suggest that 2-decylamino DMNQ has an inhibitory effect on PDGF-induced VSMC proliferation and the mechanism of this action is through cell cycle arrest at the G{sub 0}/G{sub 1} phase. This may be a useful tool for studying interventions for vascular restenosis in coronary

  14. Reduced expression of the mouse ribosomal protein Rpl17 alters the diversity of mature ribosomes by enhancing production of shortened 5.8S rRNA

    PubMed Central

    Wang, Minshi; Parshin, Andrey V.; Shcherbik, Natalia; Pestov, Dimitri G.

    2015-01-01

    Processing of rRNA during ribosome assembly can proceed through alternative pathways but it is unclear whether this could affect the structure of the ribosome. Here, we demonstrate that shortage of a ribosomal protein can change pre-rRNA processing in a way that over time alters ribosome diversity in the cell. Reducing the amount of Rpl17 in mouse cells led to stalled 60S subunit maturation, causing degradation of most of the synthesized precursors. A fraction of pre-60S subunits, however, were able to complete maturation, but with a 5′-truncated 5.8S rRNA, which we named 5.8SC. The 5′ exoribonuclease Xrn2 is involved in the generation of both 5.8SC and the canonical long form of 5.8S rRNA. Ribosomes containing 5.8SC rRNA are present in various mouse and human cells and engage in translation. These findings uncover a previously undescribed form of mammalian 5.8S rRNA and demonstrate that perturbations in ribosome assembly can be a source of heterogeneity in mature ribosomes. PMID:25995445

  15. Reduced expression of the mouse ribosomal protein Rpl17 alters the diversity of mature ribosomes by enhancing production of shortened 5.8S rRNA.

    PubMed

    Wang, Minshi; Parshin, Andrey V; Shcherbik, Natalia; Pestov, Dimitri G

    2015-07-01

    Processing of rRNA during ribosome assembly can proceed through alternative pathways but it is unclear whether this could affect the structure of the ribosome. Here, we demonstrate that shortage of a ribosomal protein can change pre-rRNA processing in a way that over time alters ribosome diversity in the cell. Reducing the amount of Rpl17 in mouse cells led to stalled 60S subunit maturation, causing degradation of most of the synthesized precursors. A fraction of pre-60S subunits, however, were able to complete maturation, but with a 5'-truncated 5.8S rRNA, which we named 5.8SC. The 5' exoribonuclease Xrn2 is involved in the generation of both 5.8S(C) and the canonical long form of 5.8S rRNA. Ribosomes containing 5.8S(C) rRNA are present in various mouse and human cells and engage in translation. These findings uncover a previously undescribed form of mammalian 5.8S rRNA and demonstrate that perturbations in ribosome assembly can be a source of heterogeneity in mature ribosomes.

  16. Polycyclic aromatic hydrocarbons (PAHs) in transplanted Manila clams (Tapes philippinarum) from the Lagoon of Venice as assessed by PAHs/shell weight index: a preliminary study.

    PubMed

    Boscolo, Rossella; Cacciatore, Federica; Giovanardi, Otello

    2007-01-01

    Variation of polycyclic aromatic hydrocarbons (PAHs) levels was assessed in Tapes philippinarum from the Lagoon of Venice. Clams were transplanted from a polluted area next to Porto Marghera to two rearing areas of the Southern Lagoon. Analyses of PAHs were made in sediments and clams by GC/MS at first sampling and after 30, 60 and 180 days. Principal component analysis was performed to elucidate bioaccumulation and depuration pattern and input sources. Biota-Sediment-Accumulation-Factor (BSAF) was applied to evaluate the PAHs input sources from sediment. Condition index was calculated to compare the seasonal variation of clam tissue to PAHs levels. To propose results not affected by seasonal changes in flesh weight of clams, the approach based on the calculation of PAHs/SW index was applied. From the results, it was concluded that PAHs/SW index is more recommendable to asses temporal variation of PAHs levels in Manila clams.

  17. Multi-edge X-ray absorption spectroscopy study of road dust samples from a traffic area of Venice using stoichiometric and environmental references

    NASA Astrophysics Data System (ADS)

    Valotto, Gabrio; Cattaruzza, Elti; Bardelli, Fabrizio

    2017-02-01

    The appropriate selection of representative pure compounds to be used as reference is a crucial step for successful analysis of X-ray absorption near edge spectroscopy (XANES) data, and it is often not a trivial task. This is particularly true when complex environmental matrices are investigated, being their elemental speciation a priori unknown. In this paper, an investigation on the speciation of Cu, Zn, and Sb based on the use of conventional (stoichiometric compounds) and non-conventional (environmental samples or relevant certified materials) references is explored. This method can be useful in when the effectiveness of XANES analysis is limited because of the difficulty in obtaining a set of references sufficiently representative of the investigated samples. Road dust samples collected along the bridge connecting Venice to the mainland were used to show the potentialities and the limits of this approach.

  18. Melanocyte-like cells in the heart and pulmonary veins contribute to atrial arrhythmia triggers

    PubMed Central

    Levin, Mark D.; Lu, Min Min; Petrenko, Nataliya B.; Hawkins, Brian J.; Gupta, Tara H.; Lang, Deborah; Buckley, Peter T.; Jochems, Jeanine; Liu, Fang; Spurney, Christopher F.; Yuan, Li J.; Jacobson, Jason T.; Brown, Christopher B.; Huang, Li; Beermann, Friedrich; Margulies, Kenneth B.; Madesh, Muniswamy; Eberwine, James H.; Epstein, Jonathan A.; Patel, Vickas V.

    2009-01-01

    Atrial fibrillation is the most common clinical cardiac arrhythmia. It is often initiated by ectopic beats arising from the pulmonary veins and atrium, but the source and mechanism of these beats remains unclear. The melanin synthesis enzyme dopachrome tautomerase (DCT) is involved in intracellular calcium and reactive species regulation in melanocytes. Given that dysregulation of intracellular calcium and reactive species has been described in patients with atrial fibrillation, we investigated the role of DCT in this process. Here, we characterize a unique DCT-expressing cell population within murine and human hearts that populated the pulmonary veins, atria, and atrioventricular canal. Expression profiling demonstrated that this population expressed adrenergic and muscarinic receptors and displayed transcriptional profiles distinct from dermal melanocytes. Adult mice lacking DCT displayed normal cardiac development but an increased susceptibility to atrial arrhythmias. Cultured primary cardiac melanocyte-like cells were excitable, and those lacking DCT displayed prolonged repolarization with early afterdepolarizations. Furthermore, mice with mutations in the tyrosine kinase receptor Kit lacked cardiac melanocyte-like cells and did not develop atrial arrhythmias in the absence of DCT. These data suggest that dysfunction of melanocyte-like cells in the atrium and pulmonary veins may contribute to atrial arrhythmias. PMID:19855129

  19. Simulation of Cardiac Arrhythmias Using a 2D Heterogeneous Whole Heart Model

    PubMed Central

    Balakrishnan, Minimol; Chakravarthy, V. Srinivasa; Guhathakurta, Soma

    2015-01-01

    Simulation studies of cardiac arrhythmias at the whole heart level with electrocardiogram (ECG) gives an understanding of how the underlying cell and tissue level changes manifest as rhythm disturbances in the ECG. We present a 2D whole heart model (WHM2D) which can accommodate variations at the cellular level and can generate the ECG waveform. It is shown that, by varying cellular-level parameters like the gap junction conductance (GJC), excitability, action potential duration (APD) and frequency of oscillations of the auto-rhythmic cell in WHM2D a large variety of cardiac arrhythmias can be generated including sinus tachycardia, sinus bradycardia, sinus arrhythmia, sinus pause, junctional rhythm, Wolf Parkinson White syndrome and all types of AV conduction blocks. WHM2D includes key components of the electrical conduction system of the heart like the SA (Sino atrial) node cells, fast conducting intranodal pathways, slow conducting atriovenctricular (AV) node, bundle of His cells, Purkinje network, atrial, and ventricular myocardial cells. SA nodal cells, AV nodal cells, bundle of His cells, and Purkinje cells are represented by the Fitzhugh-Nagumo (FN) model which is a reduced model of the Hodgkin-Huxley neuron model. The atrial and ventricular myocardial cells are modeled by the Aliev-Panfilov (AP) two-variable model proposed for cardiac excitation. WHM2D can prove to be a valuable clinical tool for understanding cardiac arrhythmias. PMID:26733873

  20. Optogenetic defibrillation terminates ventricular arrhythmia in mouse hearts and human simulations

    PubMed Central

    Boyle, Patrick M.; Vogt, Christoph C.; Karathanos, Thomas V.; Arevalo, Hermenegild J.; Fleischmann, Bernd K.; Trayanova, Natalia A.

    2016-01-01

    Ventricular arrhythmias are among the most severe complications of heart disease and can result in sudden cardiac death. Patients at risk currently receive implantable defibrillators that deliver electrical shocks to terminate arrhythmias on demand. However, strong electrical shocks can damage the heart and cause severe pain. Therefore, we have tested optogenetic defibrillation using expression of the light-sensitive channel channelrhodopsin-2 (ChR2) in cardiac tissue. Epicardial illumination effectively terminated ventricular arrhythmias in hearts from transgenic mice and from WT mice after adeno-associated virus–based gene transfer of ChR2. We also explored optogenetic defibrillation for human hearts, taking advantage of a recently developed, clinically validated in silico approach for simulating infarct-related ventricular tachycardia (VT). Our analysis revealed that illumination with red light effectively terminates VT in diseased, ChR2-expressing human hearts. Mechanistically, we determined that the observed VT termination is due to ChR2-mediated transmural depolarization of the myocardium, which causes a block of voltage-dependent Na+ channels throughout the myocardial wall and interrupts wavefront propagation into illuminated tissue. Thus, our results demonstrate that optogenetic defibrillation is highly effective in the mouse heart and could potentially be translated into humans to achieve nondamaging and pain-free termination of ventricular arrhythmia. PMID:27617859