Sample records for cardiovascular system model

  1. Computer model of cardiovascular control system responses to exercise

    NASA Technical Reports Server (NTRS)

    Croston, R. C.; Rummel, J. A.; Kay, F. J.

    1973-01-01

    Approaches of systems analysis and mathematical modeling together with computer simulation techniques are applied to the cardiovascular system in order to simulate dynamic responses of the system to a range of exercise work loads. A block diagram of the circulatory model is presented, taking into account arterial segments, venous segments, arterio-venous circulation branches, and the heart. A cardiovascular control system model is also discussed together with model test results.

  2. A novel approach to modeling and diagnosing the cardiovascular system

    SciTech Connect

    Keller, P.E.; Kangas, L.J.; Hashem, S.; Kouzes, R.T. [Pacific Northwest Lab., Richland, WA (United States); Allen, P.A. [Life Link, Richland, WA (United States)

    1995-07-01

    A novel approach to modeling and diagnosing the cardiovascular system is introduced. A model exhibits a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. Potentially, a model will be incorporated into a cardiovascular diagnostic system. This approach is unique in that each cardiovascular model is developed from physiological measurements of an individual. Any differences between the modeled variables and the variables of an individual at a given time are used for diagnosis. This approach also exploits sensor fusion to optimize the utilization of biomedical sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

  3. Exact Modeling of Cardiovascular System Using Lumped Method

    E-print Network

    Ghasemalizadeh, Omid; Firoozabadi, Bahar; Hassani, Kamran

    2014-01-01

    Electrical analogy (Lumped method) is an easy way to model human cardiovascular system. In this paper Lumped method is used for simulating a complete model. It describes a 36-vessel model and cardiac system of human body with details that could show hydrodynamic parameters of cardiovascular system. Also this paper includes modeling of pulmonary, atrium, left and right ventricles with their equivalent circuits. Exact modeling of right and left ventricles pressure increases the accuracy of our simulation. In this paper we show that a calculated pressure for aorta from our complex circuit is near to measured pressure by using advanced medical instruments.

  4. A Computer Model of the Cardiovascular System for Effective Learning.

    ERIC Educational Resources Information Center

    Rothe, Carl F.

    1979-01-01

    Described is a physiological model which solves a set of interacting, possibly nonlinear, differential equations through numerical integration on a digital computer. Sample printouts are supplied and explained for effects on the components of a cardiovascular system when exercise, hemorrhage, and cardiac failure occur. (CS)

  5. Cardiovascular simulation using a multiple modeling method on a digital computer—Simulation of interaction between the cardiovascular system and angiotensin II

    Microsoft Academic Search

    Toru Masuzawa; Yasuhiro Fukui; N. Ty Smith

    1991-01-01

    A cardiovascular system model that simulates interactive responses to drugs has been developed on a small digital computer. The overall model basically consists of three models. The first is a momentum transport model that represents relations between blood pressure and flow in the cardiovascular system. In this model, the cardiovascular system is divided into 14 components and modeled by using

  6. Modeling, Estimation and Control of Cardiovascular Systems with A Left Ventricular Assist Device

    E-print Network

    Wu, Yi

    to approximate the response of human cardiovascular circulatory system. This system model has one critical time as test environments for human cardiovascular circulatory systems with a left ventric- ular assist device patient are restored back to the normal physiologic range. Keywords: Cardiovascular circulatory system

  7. Mathematical modeling of human cardiovascular system for simulation of orthostatic response

    NASA Technical Reports Server (NTRS)

    Melchior, F. M.; Srinivasan, R. S.; Charles, J. B.

    1992-01-01

    This paper deals with the short-term response of the human cardiovascular system to orthostatic stresses in the context of developing a mathematical model of the overall system. It discusses the physiological issues involved and how these issues have been handled in published cardiovascular models for simulation of orthostatic response. Most of the models are stimulus specific with no demonstrated capability for simulating the responses to orthostatic stimuli of different types. A comprehensive model incorporating all known phenomena related to cardiovascular regulation would greatly help to interpret the various orthostatic responses of the system in a consistent manner and to understand the interactions among its elements. This paper provides a framework for future efforts in mathematical modeling of the entire cardiovascular system.

  8. Space physiology IV: mathematical modeling of the cardiovascular system in space exploration.

    PubMed

    Keith Sharp, M; Batzel, Jerry Joseph; Montani, Jean-Pierre

    2013-08-01

    Mathematical modeling represents an important tool for analyzing cardiovascular function during spaceflight. This review describes how modeling of the cardiovascular system can contribute to space life science research and illustrates this process via modeling efforts to study postflight orthostatic intolerance (POI), a key issue for spaceflight. Examining this application also provides a context for considering broader applications of modeling techniques to the challenges of bioastronautics. POI, which affects a large fraction of astronauts in stand tests upon return to Earth, presents as dizziness, fainting and other symptoms, which can diminish crew performance and cause safety hazards. POI on the Moon or Mars could be more critical. In the field of bioastronautics, POI has been the dominant application of cardiovascular modeling for more than a decade, and a number of mechanisms for POI have been investigated. Modeling approaches include computational models with a range of incorporated factors and hemodynamic sophistication, and also physical models tested in parabolic and orbital flight. Mathematical methods such as parameter sensitivity analysis can help identify key system mechanisms. In the case of POI, this could lead to more effective countermeasures. Validation is a persistent issue in modeling efforts, and key considerations and needs for experimental data to synergistically improve understanding of cardiovascular responses are outlined. Future directions in cardiovascular modeling include subject-specific assessment of system status, as well as research on integrated physiological responses, leading, for instance, to assessment of subject-specific susceptibility to POI or effects of cardiovascular alterations on muscular, vision and cognitive function. PMID:23539439

  9. Cardiovascular & Respiratory Modeling, Analysis & Control

    E-print Network

    Batzel, Jerry

    . . . . . . . . . . . . . . . . 36 1.7.3 Sensitivity analysis . . . . . . . . . . . . . . . . . . . 38 2 Respiratory Modeling 45 2Cardiovascular & Respiratory Systems: Modeling, Analysis & Control J. J. Batzel, F. Kappel, D.1 Respiratory Control Physiology . . . . . . . . . . . . . . . . . . 46 2.1.1 General features of respiration

  10. A Mathematical Model for the First-Pass Dynamics of Antibiotics Acting on the Cardiovascular System

    E-print Network

    delivered to the lungs on a first circulatory pass. Key words: Compartmental model, circulatory system, drugA Mathematical Model for the First-Pass Dynamics of Antibiotics Acting on the Cardiovascular System compounds to the lungs and heart. We use a compartmental mass balance approach to develop a system

  11. A bond graph model of the cardiovascular system Le Rolle Virginie 1 2

    E-print Network

    Boyer, Edmond

    . In this paper, a new model of the CVS, representing the ventricles, the circulatory system and the regulation activity, the circulatory system and evidently the autonomic baroreflex loop includingi) ii) iii) affereA bond graph model of the cardiovascular system Le Rolle Virginie 1 2 , Hernandez Alfredo I. 1

  12. from SIAM News, Volume 34, Number 6 Modeling the Cardiovascular System--

    E-print Network

    Canic, Suncica

    , and are certainly not applicable to the circulatory system as a whole1 from SIAM News, Volume 34, Number 6 Modeling the Cardiovascular System-- A Mathematical Adventure system, and the difficulty of coupling the different mathematical models appropriate for the different

  13. A cardiovascular system model for lower-body negative pressure response

    NASA Technical Reports Server (NTRS)

    Mitchell, B. A., Jr.; Giese, R. P.

    1971-01-01

    Mathematical models used to study complex physiological control systems are discussed. Efforts were made to modify a model of the cardiovascular system for use in studying lower body negative pressure. A computer program was written which allows orderly, straightforward expansion to include exercise, metabolism (thermal stress), respiration, and other body functions.

  14. Confronting a Cardiovascular System Model with Heart Rate and Blood Pressure Data

    E-print Network

    McSharry, Patrick E.

    Confronting a Cardiovascular System Model with Heart Rate and Blood Pressure Data PE McSharry1 fluctuations in the heart rate, blood pressure and rate of respiration. Its time evolution is governed this control mechanism and to explore the interactions between the heart rate and blood pressure. In this model

  15. Confronting a Cardiovascular System Model with Heart Rate and Blood Pressure Data

    E-print Network

    McSharry, Patrick E.

    Confronting a Cardiovascular System Model with Heart Rate and Blood Pressure Data PE McSharry 1 fluctuations in the heart rate, blood pressure and rate of respiration. Its time evolution is governed this control mechanism and to explore the interactions between the heart rate and blood pressure. In this model

  16. Modeling the cardiovascular system using a nonlinear additive autoregressive model with exogenous input

    NASA Astrophysics Data System (ADS)

    Riedl, M.; Suhrbier, A.; Malberg, H.; Penzel, T.; Bretthauer, G.; Kurths, J.; Wessel, N.

    2008-07-01

    The parameters of heart rate variability and blood pressure variability have proved to be useful analytical tools in cardiovascular physics and medicine. Model-based analysis of these variabilities additionally leads to new prognostic information about mechanisms behind regulations in the cardiovascular system. In this paper, we analyze the complex interaction between heart rate, systolic blood pressure, and respiration by nonparametric fitted nonlinear additive autoregressive models with external inputs. Therefore, we consider measurements of healthy persons and patients suffering from obstructive sleep apnea syndrome (OSAS), with and without hypertension. It is shown that the proposed nonlinear models are capable of describing short-term fluctuations in heart rate as well as systolic blood pressure significantly better than similar linear ones, which confirms the assumption of nonlinear controlled heart rate and blood pressure. Furthermore, the comparison of the nonlinear and linear approaches reveals that the heart rate and blood pressure variability in healthy subjects is caused by a higher level of noise as well as nonlinearity than in patients suffering from OSAS. The residue analysis points at a further source of heart rate and blood pressure variability in healthy subjects, in addition to heart rate, systolic blood pressure, and respiration. Comparison of the nonlinear models within and among the different groups of subjects suggests the ability to discriminate the cohorts that could lead to a stratification of hypertension risk in OSAS patients.

  17. Interactive Cardiovascular System Map

    NSDL National Science Digital Library

    The cardiovascular portion of the InnerBody website is a road map to the human cardiovascular system. It displays all of the main veins and arteries of the human body allowing the user to click on various parts of body and dozens of links to the many different systems appear. Users can hover over the links to discover what each part is named, or click on the link to be brought to a thorough definition and description of the selected system. Users may also �zoom in� on certain parts to view more detail. In addition to the interactive �map,� InnerBody also has images and descriptions about common issues that arise within the cardiovascular system.

  18. A simplified computer model of cardiovascular system with an arm branch.

    PubMed

    Chen, Baoming; Song, Tianyi; Guo, Tao; Xiang, Haiyan; Liu, Yanyong; Qin, Yufei; Cao, Zhengtao; Yu, Mengsun

    2014-01-01

    Non-invasive pressure simulators that regenerate oscillometric waveforms promise an alternative to expensive clinical trials for validating oscillometric noninvasive blood pressure devices. However, existing simulators only provide oscillometric pressure in cuff and thus have a limited accuracy. It is promising to build a physical simulator that contains a synthetic arm with a built-in brachial artery and an affiliated hydraulic model of cardiovascular system. To guide the construction of this kind of simulator, this paper presents a computer model of cardiovascular system with a relatively simple structure, where the distribution of pressures and flows in aorta root and brachial artery can be simulated, and the produced waves are accordant with the physical data. This model can be used to provide the parameters and structure that will be needed to build the new simulator. PMID:25226957

  19. Computational flow dynamics in patient specific model of cardiovascular system using CT and MRI

    NASA Astrophysics Data System (ADS)

    Yamamoto, S.; Bartsch, H.; Maruyama, S.; Yoneyama, S.; Wada, S.; Yamaguchi, T.; Naito, H.

    2006-03-01

    After introduction on a new multislice computed tomography (MSCT) scanner, it has become possible to produce highspeed CT angiography (CTA) that selected preferred method for imaging in emergent vascular conditions. On the other hand, the imaging of blood vessels is often referred to as magnetic resonance angiography (MRA). Both of angiography offers the good quality of three-dimensional information of the vessels. In this study, patient specific model were reconstructed using multi-slice computed tomography (CT) and magnetic resonance imaging (MRI). The optimal transit time from intravenous injection to enhancement cardiovascular system was determined using a contrast bolus tracking technique with CT examination and phase contrast magnetic resonance angiography (PC-MRA). The purpose of this study was to describe a novel blood flow visualization and analysis in the human cardiovascular system in more detail by constructing actual three-dimensional (3D) flow and simulated model using Computational flow dynamics (CFD) methods. CFD streamlines were displayed using a special illumination technique with blood pressure display, which gives a much better spatial understanding of the field's structure than ordinary constant-colored lines. Real vector display using PC-MRA was also expressed to compare with the CFD simulation. On conclusion, Patient specific approach using actual blood flow with PC-MRA and CFD were effective to estimate blood flow state of the cardiovascular system.

  20. [A hardware-in-the-loop simulation model of the cardiovascular system for ventricular assist device evaluation].

    PubMed

    Honglei, Li; Ming, Yang; Shiyang, Li

    2010-01-01

    This paper presents a novel technique for evaluating the performance of ventricular assist devices in vitro, innovatively combining dynamic physical testing of assist devices with a mature, numerical human cardiovascular model. Based on this technique, one self-made direct mechanical ventricular assistance (DMVA) prototype is tested. With the true representation of device performance in vivo, the real-time interactions between DMVA and the cardiovascular system are captured and studied. Hemodynamic simulations under DMVA are performed. Experimental results demonstrate that it provides a useful tool for the study of device assist impact on the cardiovascular system as well as the improvement of device structure and effectiveness of control mechanism. PMID:20391921

  1. Cardiovascular Risk in Rheumatoid Arthritis and Systemic Autoimmune Rheumatic Disorders: a Suggested Model of Preventive Strategy

    Microsoft Academic Search

    Elena Bartoloni; Alessia Alunno; Onelia Bistoni; Roberto Gerli

    The pathogenesis of accelerated cardiovascular damage commonly characterizing patients affected by systemic chronic inflammatory\\u000a and autoimmune rheumatic disorders is quite complex and still not fully clarified. However, it is well accepted that a strong\\u000a relationship between multiple factors, including both traditional cardiovascular risk factors and disease-related inflammatory\\u000a and autoimmune mechanisms, may in part explain the precocious atherosclerotic vessel damage and

  2. Velocity profile method for time varying resistance in minimal cardiovascular system models.

    PubMed

    Smith, Bram W; Chase, J Geoffrey; Nokes, Roger I; Shaw, Geoffrey M; David, Tim

    2003-10-21

    This paper investigates the fluid dynamics governing arterial flow used in lumped parameter cardiovascular system (CVS) models, particularly near the heart where arteries are large. Assumptions made in applying equations conventionally used in lumped parameter models are investigated, specifically that of constant resistance to flow. The Womersley number is used to show that the effects of time varying resistance must be modelled in the pulsatile flow through the large arteries near the heart. It is shown that the equation commonly used to include inertial effects in fluid flow calculations is inappropriate for including time varying resistance. A method of incorporating time varying resistance into a lumped parameter model is developed that uses the Navier-Stokes equations to track the velocity profile. Tests on a single-chamber model show a 17.5% difference in cardiac output for a single-chamber ventricle model when comparing constant resistance models with the velocity profile tracking method modelling time varying resistance. This increase in precision can be achieved using 20 nodes with only twice the computational time required. The method offers a fluid dynamically and physiologically accurate method of calculating large Womersley number pulsatile fluid flows in large arteries around the heart and valves. The proposed velocity profile tracking method can be easily incorporated into existing lumped parameter CVS models, improving their clinical application by increasing their accuracy. PMID:14620064

  3. Development of the Patient-specific Cardiovascular Modeling System Using Immersed Boundary Technique

    NASA Astrophysics Data System (ADS)

    Tay, Wee-Beng; Lin, Liang-Yu; Tseng, Wen-Yih; Tseng, Yu-Heng

    2010-05-01

    A computational fluid dynamics (CFD) based, patient-specific cardiovascular modeling system is under-developed. The system can identify possible diseased conditions and facilitate physicians' diagnosis at early stage through the hybrid CFD simulation and time-resolved magnetic resonance imaging (MRI). The CFD simulation is initially based on the three-dimensional heart model developed by McQueen and Peskin, which can simultaneously compute fluid motions and elastic boundary motions using the immersed boundary method. We extend and improve the three-dimensional heart model for the clinical application by including the patient-specific hemodynamic information. The flow features in the ventricles and their responses are investigated under different inflow and outflow conditions during diastole and systole phases based on the quasi-realistic heart model, which takes advantage of the observed flow scenarios. Our results indicate distinct differences between the two groups of participants, including the vortex formation process in the left ventricle (LV), as well as the flow rate distributions at different identified sources such as the aorta, vena cava and pulmonary veins/artery. We further identify some key parameters which may affect the vortex formation in the LV. Thus it is hypothesized that disease-related dysfunctions in intervals before complete heart failure can be observed in the dynamics of transmitral blood flow during early LV diastole.

  4. Weightlessness simulations for cardiovascular and muscle systems: validity of rat models.

    PubMed

    Musacchia, X J; Fagette, S

    1997-10-01

    Animal models are widely used to evoke responses comparable to those obtained during weightlessness. Two models are reviewed; one examines cardiovascular responses and cephalad fluid shifts in head down tilting (HDT), and the other examines atrophy in load bearing muscles by unloading the hind limbs. Cephalad fluid shifts result in diuresis, natriuresis, and kaliuresis. Reversals are rapid, within one week. Reports of cardiovascular responses are not similar among various laboratories, probably due to variations in protocols. Blood pressures (MAP, SP and DP) and heart rates measured with direct aorta cannulations become elevated as early as one and three days of HDT; recovery occurs within several hours; the response is a transient hypertension. The role of central and peripheral sympathetic nervous activity in flight and suspended rats is examined. Rats show little or no evidence of cardiac deconditioning. Direct blood pressures have not been made in flight rats, precluding direct comparisons with earth side experiments. Muscle atrophy and load bearing (slow twitch fibers) and non-load bearing (fast twitch fibers) muscle responses with hind limb unloading and recovery are compared with flight animal responses. Soleus muscle in response to whole body suspension (WBS), tail suspension (TS) or flight exposure consistently shows significant weight loss. In contrast, the extensor digitorum longus and vastus medialis show less marked responses. More specifically, slow twitch fibers in all these muscles show the greatest loss in mass (e.g. cross sectional areas). The conclusion is that both WBS or TS systems are useful in predicting and comparing changes due to weightless flight. PMID:11541869

  5. Modeling of short-term mechanism of arterial pressure control in the cardiovascular system: object-oriented and acausal approach.

    PubMed

    Kulhánek, Tomáš; Kofránek, Ji?í; Mateják, Marek

    2014-11-01

    This letter introduces an alternative approach to modeling the cardiovascular system with a short-term control mechanism published in Computers in Biology and Medicine, Vol. 47 (2014), pp. 104-112. We recommend using abstract components on a distinct physical level, separating the model into hydraulic components, subsystems of the cardiovascular system and individual subsystems of the control mechanism and scenario. We recommend utilizing an acausal modeling feature of Modelica language, which allows model variables to be expressed declaratively. Furthermore, the Modelica tool identifies which are the dependent and independent variables upon compilation. An example of our approach is introduced on several elementary components representing the hydraulic resistance to fluid flow and the elastic response of the vessel, among others. The introduced model implementation can be more reusable and understandable for the general scientific community. PMID:25240104

  6. MODELING BLOOD FLOW IN THE CARDIOVASCULAR

    E-print Network

    Olufsen, Mette Sofie

    to be produced and consumed at the ends of a transport system whereas idea of a circulatory blood system of the circulatory cardiovasclar system § Harvey discovered the circulation of blood 46 year before the discoveryMODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA325 ­ Spring 2013 Department of Mathematics

  7. MODELING BLOOD FLOW IN THE CARDIOVASCULAR

    E-print Network

    Olufsen, Mette Sofie

    was thought to be produced and consumed at the ends of a transport system whereas idea of a circulatory blood the discovery of the circulatory cardiovasclar system § Harvey discovered the circulation of blood 46 yearMODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA432 ­ Spring 2013 Department of Mathematics

  8. Mathematical multi-scale model of the cardiovascular system including mitral valve dynamics. Application to ischemic mitral insufficiency

    PubMed Central

    2011-01-01

    Background Valve dysfunction is a common cardiovascular pathology. Despite significant clinical research, there is little formal study of how valve dysfunction affects overall circulatory dynamics. Validated models would offer the ability to better understand these dynamics and thus optimize diagnosis, as well as surgical and other interventions. Methods A cardiovascular and circulatory system (CVS) model has already been validated in silico, and in several animal model studies. It accounts for valve dynamics using Heaviside functions to simulate a physiologically accurate "open on pressure, close on flow" law. However, it does not consider real-time valve opening dynamics and therefore does not fully capture valve dysfunction, particularly where the dysfunction involves partial closure. This research describes an updated version of this previous closed-loop CVS model that includes the progressive opening of the mitral valve, and is defined over the full cardiac cycle. Results Simulations of the cardiovascular system with healthy mitral valve are performed, and, the global hemodynamic behaviour is studied compared with previously validated results. The error between resulting pressure-volume (PV) loops of already validated CVS model and the new CVS model that includes the progressive opening of the mitral valve is assessed and remains within typical measurement error and variability. Simulations of ischemic mitral insufficiency are also performed. Pressure-Volume loops, transmitral flow evolution and mitral valve aperture area evolution follow reported measurements in shape, amplitude and trends. Conclusions The resulting cardiovascular system model including mitral valve dynamics provides a foundation for clinical validation and the study of valvular dysfunction in vivo. The overall models and results could readily be generalised to other cardiac valves. PMID:21942971

  9. Towards patient-specific cardiovascular modeling system using the immersed boundary technique

    PubMed Central

    2011-01-01

    Background Previous research shows that the flow dynamics in the left ventricle (LV) reveal important information about cardiac health. This information can be used in early diagnosis of patients with potential heart problems. The current study introduces a patient-specific cardiovascular-modelling system (CMS) which simulates the flow dynamics in the LV to facilitate physicians in early diagnosis of patients before heart failure. Methods The proposed system will identify possible disease conditions and facilitates early diagnosis through hybrid computational fluid dynamics (CFD) simulation and time-resolved magnetic resonance imaging (4-D MRI). The simulation is based on the 3-D heart model, which can simultaneously compute fluid and elastic boundary motions using the immersed boundary method. At this preliminary stage, the 4-D MRI is used to provide an appropriate comparison. This allows flexible investigation of the flow features in the ventricles and their responses. Results The results simulate various flow rates and kinetic energy in the diastole and systole phases, demonstrating the feasibility of capturing some of the important characteristics of the heart during different phases. However, some discrepancies exist in the pulmonary vein and aorta flow rate between the numerical and experimental data. Further studies are essential to investigate and solve the remaining problems before using the data in clinical diagnostics. Conclusions The results show that by using a simple reservoir pressure boundary condition (RPBC), we are able to capture some essential variations found in the clinical data. Our approach establishes a first-step framework of a practical patient-specific CMS, which comprises a 3-D CFD model (without involving actual hemodynamic data yet) to simulate the heart and the 4-D PC-MRI system. At this stage, the 4-D PC-MRI system is used for verification purpose rather than input. This brings us closer to our goal of developing a practical patient-specific CMS, which will be pursued next. We anticipate that in the future, this hybrid system can potentially identify possible disease conditions in LV through comprehensive analysis and facilitates physicians in early diagnosis of probable cardiac problems. PMID:21682851

  10. PPARs and the Cardiovascular System

    PubMed Central

    Hamblin, Milton; Chang, Lin; Fan, Yanbo; Zhang, Jifeng

    2009-01-01

    Abstract Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone-receptor superfamily. Originally cloned in 1990, PPARs were found to be mediators of pharmacologic agents that induce hepatocyte peroxisome proliferation. PPARs also are expressed in cells of the cardiovascular system. PPAR? appears to be highly expressed during atherosclerotic lesion formation, suggesting that increased PPAR? expression may be a vascular compensatory response. Also, ligand-activated PPAR? decreases the inflammatory response in cardiovascular cells, particularly in endothelial cells. PPAR?, similar to PPAR?, also has pleiotropic effects in the cardiovascular system, including antiinflammatory and antiatherosclerotic properties. PPAR? activation inhibits vascular smooth muscle proinflammatory responses, attenuating the development of atherosclerosis. However, PPAR? overexpression may lead to elevated macrophage inflammation and atherosclerosis. Conversely, PPAR? ligands are shown to attenuate the pathogenesis of atherosclerosis by improving endothelial cell proliferation and survival while decreasing endothelial cell inflammation and vascular smooth muscle cell proliferation. Furthermore, the administration of PPAR ligands in the form of TZDs and fibrates has been disappointing in terms of markedly reducing cardiovascular events in the clinical setting. Therefore, a better understanding of PPAR-dependent and -independent signaling will provide the foundation for future research on the role of PPARs in human cardiovascular biology. Antioxid. Redox Signal. 11, 1415–1452. PMID:19061437

  11. Cardiovascular Magnetic Resonance Imaging in Experimental Models

    PubMed Central

    Price, Anthony N.; Cheung, King K.; Cleary, Jon O; Campbell, Adrienne E; Riegler, Johannes; Lythgoe, Mark F

    2010-01-01

    Cardiovascular magnetic resonance (CMR) imaging is the modality of choice for clinical studies of the heart and vasculature, offering detailed images of both structure and function with high temporal resolution. Small animals are increasingly used for genetic and translational research, in conjunction with models of common pathologies such as myocardial infarction. In all cases, effective methods for characterising a wide range of functional and anatomical parameters are crucial for robust studies. CMR is the gold-standard for the non-invasive examination of these models, although physiological differences, such as rapid heart rate, make this a greater challenge than conventional clinical imaging. However, with the help of specialised magnetic resonance (MR) systems, novel gating strategies and optimised pulse sequences, high-quality images can be obtained in these animals despite their small size. In this review, we provide an overview of the principal CMR techniques for small animals for example cine, angiography and perfusion imaging, which can provide measures such as ejection fraction, vessel anatomy and local blood flow, respectively. In combination with MR contrast agents, regional dysfunction in the heart can also be identified and assessed. We also discuss optimal methods for analysing CMR data, particularly the use of semi-automated tools for parameter measurement to reduce analysis time. Finally, we describe current and emerging methods for imaging the developing heart, aiding characterisation of congenital cardiovascular defects. Advanced small animal CMR now offers an unparalleled range of cardiovascular assessments. Employing these methods should allow new insights into the structural, functional and molecular basis of the cardiovascular system. PMID:21331311

  12. [Altitude and the cardiovascular system].

    PubMed

    Richalet, Jean-Paul

    2012-06-01

    A stay at high altitude exposes an individual to various environmental changes (cold, exercise, isolation) but the most stressful for the body is hypoxia. However, the cardiovascular system yields some efficient mechanisms of acclimatization to oxygen lack. Hypoxia activates the adrenergic system and induces a tachycardia that decreases during a prolonged stay at altitude. The desensitization of the adrenergic system leads to a decrease in maximal heart rate and a protection of the myocardium against an energy disequilibrium that could be potentially harmful for the heart. Hypoxia induces a peripheral vasodilation and a pulmonary vasoconstriction, leading to few changes in systemic blood pressure and an increase in pulmonary blood pressure (PHT) that can contribute to a high altitude pulmonary edema. Advice to a cardiac patient who plans to go to high altitude should take into account that all diseases aggravated by increased adrenergic activity or associated with a PHT or a hypoxemia (right-to-left shunt) will be aggravated at high altitude. As altitude increases, a patient with a coronary disease will present an ischemic threshold for a lower power output during an EKG exercise test. The only test allowing predicting the tolerance to high altitude is the hypoxia exercise test realized at 30% of maxVO(2)and at an equivalent altitude of 4,800m. PMID:22421600

  13. Efficacy of Female Rat Models in Translational Cardiovascular Aging Research

    PubMed Central

    Rice, K. M.; Fannin, J. C.; Gillette, C.; Blough, E. R.

    2014-01-01

    Cardiovascular disease is the leading cause of death in women in the United States. Aging is a primary risk factor for the development of cardiovascular disease as well as cardiovascular-related morbidity and mortality. Aging is a universal process that all humans undergo; however, research in aging is limited by cost and time constraints. Therefore, most research in aging has been done in primates and rodents; however it is unknown how well the effects of aging in rat models translate into humans. To compound the complication of aging gender has also been indicated as a risk factor for various cardiovascular diseases. This review addresses the systemic pathophysiology of the cardiovascular system associated with aging and gender for aging research with regard to the applicability of rat derived data for translational application to human aging. PMID:25610649

  14. Cardiovascular Interactions Model and Demonstration

    NSDL National Science Digital Library

    PhD Carl F. Rothe (Indiana University School of Medicine Department of Cellular and Integrative Physiology)

    2005-06-22

    The Cardiovascular Interactions Project is an electronic active learning tool that demonstrates the complex and intricate interactions between the functions of the heart and peripheral circulation to provide an adequate cardiac output during various stresses.

  15. The Gross Physiology of the Cardiovascular System

    NSDL National Science Digital Library

    Dr. Robert M Anderson (University of Arizona)

    2012-01-20

    A global analysis of the mechanical function of the cardiovascular system that explains fundamental concepts, such as: The unique hydraulic characteristics of the heart as a pump and the cardiovascular system; the determinants of cardiac output; the mechanism that maintains blood volume equilibrium between the systemic and pulmonary circuits; and the primary contribution of the atria to circulation rate. Free downloadable text and online video available.

  16. Targets of oxidative stress in cardiovascular system

    Microsoft Academic Search

    Sajal Chakraborti; Tapati Chakraborti; John R. Michael; Sandip K. Batabyal; Salil K. Ghosh

    1998-01-01

    Although oxidants such as superoxide (O2.-) and hydrogen peroxide (H2O2) play a role in host-mediated destruction of foreign pathogens yet excessive generation of oxidants may lead to a variety of pathological complications in the cardiovascular system. An important mechanism by which oxidants cause dysfunction of the cardiovascular system appears to be due to the increase in intracellular free Ca2+ concentration.

  17. Systems-based approaches to cardiovascular disease

    PubMed Central

    MacLellan, W. Robb; Wang, Yibin; Lusis, Aldons J.

    2013-01-01

    Common cardiovascular diseases, such as atherosclerosis and congestive heart failure, are exceptionally complex, involving a multitude of environmental and genetic factors that often show nonlinear interactions as well as being highly dependent on sex, age, and even the maternal environment. Although focused, reductionistic approaches have led to progress in elucidating the pathophysiology of cardiovascular diseases, such approaches are poorly powered to address complex interactions. Over the past decade, technological advances have made it possible to interrogate biological systems on a global level, raising hopes that, in combination with computational approaches, it may be possible to more fully address the complexities of cardiovascular diseases. In this Review, we provide an overview of such systems-based approaches to cardiovascular disease and discuss their translational implications. PMID:22231714

  18. Exercise and the Cardiovascular System

    PubMed Central

    Golbidi, Saeid; Laher, Ismail

    2012-01-01

    There are alarming increases in the incidence of obesity, insulin resistance, type II diabetes, and cardiovascular disease. The risk of these diseases is significantly reduced by appropriate lifestyle modifications such as increased physical activity. However, the exact mechanisms by which exercise influences the development and progression of cardiovascular disease are unclear. In this paper we review some important exercise-induced changes in cardiac, vascular, and blood tissues and discuss recent clinical trials related to the benefits of exercise. We also discuss the roles of boosting antioxidant levels, consequences of epicardial fat reduction, increases in expression of heat shock proteins and endoplasmic reticulum stress proteins, mitochondrial adaptation, and the role of sarcolemmal and mitochondrial potassium channels in the contributing to the cardioprotection offered by exercise. In terms of vascular benefits, the main effects discussed are changes in exercise-induced vascular remodeling and endothelial function. Exercise-induced fibrinolytic and rheological changes also underlie the hematological benefits of exercise. PMID:22701195

  19. Mathematical modelling of the human foetal cardiovascular system based on Doppler ultrasound data

    Microsoft Academic Search

    G. Pennati; M. Bellotti; R. Fumero

    1997-01-01

    A lumped parameter model of the human foetal circulation primarily based on blood velocity data derived from the Doppler analysis was developed in this study. It consists of two major parts, the heart and the foetal vascular circulation. The heart model accounts for both ventricular and atrial contractility. The circulation was divided into 19 compliant vascular compartments in order to

  20. A population model of integrative cardiovascular physiology.

    PubMed

    Pruett, William A; Husband, Leland D; Husband, Graham; Dakhlalla, Muhammad; Bellamy, Kyle; Coleman, Thomas G; Hester, Robert L

    2013-01-01

    We present a small integrative model of human cardiovascular physiology. The model is population-based; rather than using best fit parameter values, we used a variant of the Metropolis algorithm to produce distributions for the parameters most associated with model sensitivity. The population is built by sampling from these distributions to create the model coefficients. The resulting models were then subjected to a hemorrhage. The population was separated into those that lost less than 15 mmHg arterial pressure (compensators), and those that lost more (decompensators). The populations were parametrically analyzed to determine baseline conditions correlating with compensation and decompensation. Analysis included single variable correlation, graphical time series analysis, and support vector machine (SVM) classification. Most variables were seen to correlate with propensity for circulatory collapse, but not sufficiently to effect reasonable classification by any single variable. Time series analysis indicated a single significant measure, the stressed blood volume, as predicting collapse in situ, but measurement of this quantity is clinically impossible. SVM uncovered a collection of variables and parameters that, when taken together, provided useful rubrics for classification. Due to the probabilistic origins of the method, multiple classifications were attempted, resulting in an average of 3.5 variables necessary to construct classification. The most common variables used were systemic compliance, baseline baroreceptor signal strength and total peripheral resistance, providing predictive ability exceeding 90%. The methods presented are suitable for use in any deterministic mathematical model. PMID:24058546

  1. MODELING CARDIOVASCULAR AND RESPIRATORY DYNAMICS IN CONGESTIVE HEART FAILURE

    E-print Network

    Olufsen, Mette Sofie

    ]. Respiratory changes duiring sleep combined with these cardiovascular and control sensitivity changes can, Respiratory modeling, Parameter estimation, Model validation, Sensitivity analysis, Subset selection. 1 #12MODELING CARDIOVASCULAR AND RESPIRATORY DYNAMICS IN CONGESTIVE HEART FAILURE LAURA M. ELLWEIN1

  2. Acute pneumonia and the cardiovascular system.

    PubMed

    Corrales-Medina, Vicente F; Musher, Daniel M; Shachkina, Svetlana; Chirinos, Julio A

    2013-02-01

    Although traditionally regarded as a disease confined to the lungs, acute pneumonia has important effects on the cardiovascular system at all severities of infection. Pneumonia tends to affect individuals who are also at high cardiovascular risk. Results of recent studies show that about a quarter of adults admitted to hospital with pneumonia develop a major acute cardiac complication during their hospital stay, which is associated with a 60% increase in short-term mortality. These findings suggest that outcomes of patients with pneumonia can be improved by prevention of the development and progression of associated cardiac complications. Before this hypothesis can be tested, however, an adequate mechanistic understanding of the cardiovascular changes that occur during pneumonia, and their role in the trigger of various cardiac complications, is needed. In this Review, we summarise knowledge about the burden of cardiac complications in adults with acute pneumonia, the cardiovascular response to this infection, the potential effects of commonly used cardiovascular and anti-infective drugs on these associations, and possible directions for future research. PMID:23332146

  3. Exercise and the Cardiovascular System: Clinical Science and Cardiovascular Outcomes.

    PubMed

    Lavie, Carl J; Arena, Ross; Swift, Damon L; Johannsen, Neil M; Sui, Xuemei; Lee, Duck-Chul; Earnest, Conrad P; Church, Timothy S; O'Keefe, James H; Milani, Richard V; Blair, Steven N

    2015-07-01

    Substantial evidence has established the value of high levels of physical activity, exercise training (ET), and overall cardiorespiratory fitness in the prevention and treatment of cardiovascular diseases. This article reviews some basics of exercise physiology and the acute and chronic responses of ET, as well as the effect of physical activity and cardiorespiratory fitness on cardiovascular diseases. This review also surveys data from epidemiological and ET studies in the primary and secondary prevention of cardiovascular diseases, particularly coronary heart disease and heart failure. These data strongly support the routine prescription of ET to all patients and referrals for patients with cardiovascular diseases, especially coronary heart disease and heart failure, to specific cardiac rehabilitation and ET programs. PMID:26139859

  4. The Heart of Our Cardiovascular System

    NSDL National Science Digital Library

    Bio-Inspired Technology and Systems (BITS) RET,

    Students learn about the heart and its role at the center of the human cardiovascular system. In the associated activity, students play out a scenario in which they are biomedical engineers asked to design artificial hearts. They learn about the path of blood flow through the heart and use that knowledge to evaluate designs of artificial hearts on the market.

  5. Modeling and simulating human cardiovascular response to acceleration

    E-print Network

    Zamanian, Sam Ahmad

    2007-01-01

    The human cardiovascular system routinely encounters conditions that cause it to adapt. For example, when an astronaut enters microgravity, his/her cardiovascular system adapts rapidly to the weightless environment with ...

  6. Modelling of long-term and short-term mechanisms of arterial pressure control in the cardiovascular system: an object-oriented approach.

    PubMed

    Fernandez de Canete, J; Luque, J; Barbancho, J; Munoz, V

    2014-04-01

    A mathematical model that provides an overall description of both the short- and long-term mechanisms of arterial pressure regulation is presented. Short-term control is exerted through the baroreceptor reflex while renal elimination plays a role in long-term control. Both mechanisms operate in an integrated way over the compartmental model of the cardiovascular system. The whole system was modelled in MODELICA, which uses a hierarchical object-oriented modelling strategy, under the DYMOLA simulation environment. The performance of the controlled system was analysed by simulation in light of the existing hypothesis and validation tests previously performed with physiological data, demonstrating the effectiveness of both regulation mechanisms under physiological and pathological conditions. PMID:24561348

  7. Modeling Cardiovascular Anatomy from Patient-Specific Imaging Data

    E-print Network

    Texas at Austin, University of

    Modeling Cardiovascular Anatomy from Patient-Specific Imaging Data Chandrajit Bajaj1 and Samrat Introduction The importance of modern imaging techniques for capturing detailed struc- tural information of a biological system cannot be understated. Unfortunately images do not reveal the "full functional story

  8. Mathematical biomarkers for the autonomic regulation of cardiovascular system.

    PubMed

    Campos, Luciana A; Pereira, Valter L; Muralikrishna, Amita; Albarwani, Sulayma; Brás, Susana; Gouveia, Sónia

    2013-01-01

    Heart rate and blood pressure are the most important vital signs in diagnosing disease. Both heart rate and blood pressure are characterized by a high degree of short term variability from moment to moment, medium term over the normal day and night as well as in the very long term over months to years. The study of new mathematical algorithms to evaluate the variability of these cardiovascular parameters has a high potential in the development of new methods for early detection of cardiovascular disease, to establish differential diagnosis with possible therapeutic consequences. The autonomic nervous system is a major player in the general adaptive reaction to stress and disease. The quantitative prediction of the autonomic interactions in multiple control loops pathways of cardiovascular system is directly applicable to clinical situations. Exploration of new multimodal analytical techniques for the variability of cardiovascular system may detect new approaches for deterministic parameter identification. A multimodal analysis of cardiovascular signals can be studied by evaluating their amplitudes, phases, time domain patterns, and sensitivity to imposed stimuli, i.e., drugs blocking the autonomic system. The causal effects, gains, and dynamic relationships may be studied through dynamical fuzzy logic models, such as the discrete-time model and discrete-event model. We expect an increase in accuracy of modeling and a better estimation of the heart rate and blood pressure time series, which could be of benefit for intelligent patient monitoring. We foresee that identifying quantitative mathematical biomarkers for autonomic nervous system will allow individual therapy adjustments to aim at the most favorable sympathetic-parasympathetic balance. PMID:24109456

  9. Mathematical biomarkers for the autonomic regulation of cardiovascular system

    PubMed Central

    Campos, Luciana A.; Pereira, Valter L.; Muralikrishna, Amita; Albarwani, Sulayma; Brás, Susana; Gouveia, Sónia

    2013-01-01

    Heart rate and blood pressure are the most important vital signs in diagnosing disease. Both heart rate and blood pressure are characterized by a high degree of short term variability from moment to moment, medium term over the normal day and night as well as in the very long term over months to years. The study of new mathematical algorithms to evaluate the variability of these cardiovascular parameters has a high potential in the development of new methods for early detection of cardiovascular disease, to establish differential diagnosis with possible therapeutic consequences. The autonomic nervous system is a major player in the general adaptive reaction to stress and disease. The quantitative prediction of the autonomic interactions in multiple control loops pathways of cardiovascular system is directly applicable to clinical situations. Exploration of new multimodal analytical techniques for the variability of cardiovascular system may detect new approaches for deterministic parameter identification. A multimodal analysis of cardiovascular signals can be studied by evaluating their amplitudes, phases, time domain patterns, and sensitivity to imposed stimuli, i.e., drugs blocking the autonomic system. The causal effects, gains, and dynamic relationships may be studied through dynamical fuzzy logic models, such as the discrete-time model and discrete-event model. We expect an increase in accuracy of modeling and a better estimation of the heart rate and blood pressure time series, which could be of benefit for intelligent patient monitoring. We foresee that identifying quantitative mathematical biomarkers for autonomic nervous system will allow individual therapy adjustments to aim at the most favorable sympathetic-parasympathetic balance. PMID:24109456

  10. Opto-physiological modeling applied to photoplethysmographic cardiovascular assessment.

    PubMed

    Hu, Sijung; Azorin-Peris, Vicente; Zheng, Jia

    2013-01-01

    This paper presents opto-physiological (OP) modeling and its application in cardiovascular assessment techniques based on photoplethysmography (PPG). Existing contact point measurement techniques, i.e., pulse oximetry probes, are compared with the next generation non-contact and imaging implementations, i.e., non-contact reflection and camera-based PPG. The further development of effective physiological monitoring techniques relies on novel approaches to OP modeling that can better inform the design and development of sensing hardware and applicable signal processing procedures. With the help of finite-element optical simulation, fundamental research into OP modeling of photoplethysmography is being exploited towards the development of engineering solutions for practical biomedical systems. This paper reviews a body of research comprising two OP models that have led to significant progress in the design of transmission mode pulse oximetry probes, and approaches to 3D blood perfusion mapping for the interpretation of cardiovascular performance. PMID:24287429

  11. TEMPORAL ASSOCIATION BETWEEN PULMONARY AND SYSTEMIC EFFECTS OF PARTICULATE MATTER IN HEALTHY AND CARDIOVASCULAR COMPROMISED RATS

    Microsoft Academic Search

    Urmila P. Kodavanti; Mette C. Schladweiler; Allen D. Ledbetter; Russ Hauser; David C. Christiani; John McGee; Judy R. Richards; Daniel L. Costa

    2002-01-01

    Exposure to particulate matter (PM) has been associated with increased morbidity and mortality among individuals with cardiovascular disease. It is hypothesized that systemic alterations occur concurrent to pulmonary injury\\/inflammation, and contribute to cardiac events in compromised hosts. We explored this hypothesis using a rat model for human hypertension and cardiovascular disease (spontaneously hypertensive, SH), and normotensive Wistar Kyoto (WKY) rats.

  12. Development of the National Cardiovascular Information System (NCIS) in Ireland

    Microsoft Academic Search

    M. Rachel Flynn; Moira Lonergan; Peter Kearney; Emer Shelley

    2005-01-01

    The National Cardiovascular Information System (NCIS) is described as a series of integrated cardiology care registers designed to collect data on the clinical care of patients with cardiac disease in acute hospitals in Ireland. The aim of this paper is to provide information on the National Cardiovascular Information System (NCIS), including the background to the development of the system and

  13. Degradation Model of Bioabsorbable Cardiovascular Stents

    PubMed Central

    Luo, Qiyi; Liu, Xiangkun; Li, Zhonghua; Huang, Chubo; Zhang, Wen; Meng, Juan; Chang, Zhaohua; Hua, Zezhao

    2014-01-01

    This study established a numerical model to investigate the degradation mechanism and behavior of bioabsorbable cardiovascular stents. In order to generate the constitutive degradation material model, the degradation characteristics were characterized with user-defined field variables. The radial strength bench test and analysis were used to verify the material model. In order to validate the numerical degradation model, in vitro bench test and in vivo implantation studies were conducted under physiological and normal conditions. The results showed that six months of degradation had not influenced the thermodynamic properties and mechanical integrity of the stent while the molecular weight of the stents implanted in the in vivo and in vitro models had decreased to 61.8% and 68.5% respectively after six month's implantation. It was also found that the degradation rate, critical locations and changes in diameter of the stents in the numerical model were in good consistency in both in vivo and in vitro studies. It implies that the numerical degradation model could provide useful physical insights and prediction of the stent degradation behavior and evaluate, to some extent, the in-vivo performance of the stent. This model could eventually be used for design and optimization of bioabsorbable stent. PMID:25365310

  14. Shear forces and blood vessel radii in the cardiovascular system

    Microsoft Academic Search

    M. ZAMIR

    1977-01-01

    A B S TR A C T What mathematical or physiological principles govern the radii of blood vessels in the cardiovascular system and by what mechanisms are these principles implemented? This question is studied in the contexts of fluid dynamics and physiology of the cardiovascular system, and a possible answer is examined in the light of empirical data.

  15. Regulation of sympathetic nervous system function after cardiovascular deconditioning

    NASA Technical Reports Server (NTRS)

    Hasser, E. M.; Moffitt, J. A.

    2001-01-01

    Humans subjected to prolonged periods of bed rest or microgravity undergo deconditioning of the cardiovascular system, characterized by resting tachycardia, reduced exercise capability, and a predisposition for orthostatic intolerance. These changes in cardiovascular function are likely due to a combination of factors, including changes in control of body fluid balance or cardiac alterations resulting in inadequate maintenance of stroke volume, altered arterial or venous vascular function, reduced activation of cardiovascular hormones, and diminished autonomic reflex function. There is evidence indicating a role for each of these mechanisms. Diminished reflex activation of the sympathetic nervous system and subsequent vasoconstriction appear to play an important role. Studies utilizing the hindlimb-unloaded (HU) rat, an animal model of deconditioning, evaluated the potential role of altered arterial baroreflex control of the sympathetic nervous system. These studies indicate that HU results in blunted baroreflex-mediated activation of both renal and lumbar sympathetic nerve activity in response to a hypotensive stimulus. HU rats are less able to maintain arterial pressure during hemorrhage, suggesting that diminished ability to increase sympathetic activity has functional consequences for the animal. Reflex control of vasopressin secretion appears to be enhanced following HU. Blunted baroreflex-mediated sympathoexcitation appears to involve altered central nervous system function. Baroreceptor afferent activity in response to changes in arterial pressure is unaltered in HU rats. However, increases in efferent sympathetic nerve activity for a given decrease in afferent input are blunted after HU. This altered central nervous system processing of baroreceptor inputs appears to involve an effect at the rostral ventrolateral medulla (RVLM). Specifically, it appears that tonic GABAA-mediated inhibition of the RVLM is enhanced after HU. Augmented inhibition apparently arises from sources other than the caudal ventrolateral medulla. If similar alterations in control of the sympathetic nervous system occur in humans in response to cardiovascular deconditioning, it is likely that they play an important role in the observed tendency for orthostatic intolerance. Combined with potential changes in vascular function, cardiac function, and hypovolemia, the predisposition for orthostatic intolerance following cardiovascular deconditioning would be markedly enhanced by blunted ability to reflexly activate the sympathetic nervous system.

  16. A mock circulation model for cardiovascular device evaluation.

    PubMed

    Schampaert, S; Pennings, K A M A; van de Molengraft, M J G; Pijls, N H J; van de Vosse, F N; Rutten, M C M

    2014-04-01

    The aim of this study was to develop an integrated mock circulation system that functions in a physiological manner for testing cardiovascular devices under well-controlled circumstances. In contrast to previously reported mock loops, the model includes a systemic, pulmonary, and coronary circulation, an elaborate heart contraction model, and a realistic heart rate control model. The behavior of the presented system was tested in response to changes in left ventricular contractile states, loading conditions, and heart rate. For validation purposes, generated hemodynamic parameters and responses were compared to literature. The model was implemented in a servo-motor driven mock loop, together with a relatively simple lead-lag controller. The pressure and flow signals measured closely mimicked human pressure under both physiological and pathological conditions. In addition, the system's response to changes in preload, afterload, and heart rate indicate a proper implementation of the incorporated feedback mechanisms (frequency and cardiac function control). Therefore, the presented mock circulation allows for generic in vitro testing of cardiovascular devices under well-controlled circumstances. PMID:24622168

  17. Molecular Biology of the Cardiovascular System MED/BENG 238

    E-print Network

    Gleeson, Joseph G.

    Molecular Biology of the Cardiovascular System MED/BENG 238 4 Units Winter Quarter 2011 January 4th/17 Roles of Fluid Mechanics in Cardiovascular Molecular Biology Prof. Shu Chien 02/22 - 02/24 Molecular Biology of Atherosclerosis Prof. Wulf Palinski 03/01 ­ 03/03 Molecular Biology of Lipoproteins Prof. Sam

  18. 76 FR 47143 - Approval for Manufacturing Authority, Foreign-Trade Zone 153; Abbott Cardiovascular Systems, Inc...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ...Authority, Foreign-Trade Zone 153; Abbott Cardiovascular Systems, Inc., (Cardiovascular Devices), Riverside County, CA Pursuant...manufacturing authority on behalf of Abbott Cardiovascular Systems, Inc., within Sites 11-13 of...

  19. The CardioVascular System in Space

    Microsoft Academic Search

    Gilles Clément

    \\u000a One of the major concerns for both short- and long-duration spaceflight is the phenomenon of cardio-vascular deconditioning.\\u000a Exercise deconditioning during spaceflight may significantly affect a crewmember’s ability to perform strenuous or prolonged\\u000a tasks during and after a spaceflight mission, respond to an emergency situation, or assist a crewmate who might be incapacitated.\\u000a This chapter introduces the principles of cardio-vascular fluid

  20. Electronic Records with Cardiovascular Monitoring System

    Microsoft Academic Search

    Angelmar Constantino Roman; Hugo Bulegon; Silvio Bortoleto; Nelson Ebecken

    Cardiovascular diseases are the most responsible for the deaths of adults in most parts of the world. To facilitate its clinical\\u000a management in primary health care is fundamental to improving the efficiency and seeks to reduce the morbidity and mortality.\\u000a This article describes a software focused on the management of major cardiovascular risk factors (diabetes, hypertension,\\u000a Dyslipidemia, smoking). Starting by

  1. Gravitational Force and the Cardiovascular System

    NASA Technical Reports Server (NTRS)

    Pendergast, D. R.; Olszowka, A. J.; Rokitka, M. A.; Farhi, L. E.

    1991-01-01

    Cardiovascular responses to changes in gravitational force are considered. Man is ideally suited to his 1-g environment. Although cardiovascular adjustments are required to accommodate to postural changes and exercise, these are fully accomplished for short periods (min). More challenging stresses are those of short-term microgravity (h) and long-term microgravity (days) and of gravitational forces greater than that of Earth. The latter can be simulated in the laboratory and quantitative studies can be conducted.

  2. Mechanisms of Lipotoxicity in the Cardiovascular System

    PubMed Central

    Wende, Adam R.; Symons, J. David; Abel, E. Dale

    2012-01-01

    Cardiovascular diseases account for approximately one third of all deaths globally. Obese and diabetic patients have a high likelihood of dying from complications associated with cardiovascular dysfunction. Obesity and diabetes increase circulating lipids that upon tissue uptake, may be stored as triglyceride, or may be metabolized in other pathways, leading to the generation of toxic intermediates. Excess lipid utilization or activation of signaling pathways by lipid metabolites may disrupt cellular homeostasis and contribute to cell death, defining the concept of lipotoxicity. Lipotoxicity occurs in multiple organs, including cardiac and vascular tissues, and a number of specific mechanisms have been proposed to explain lipotoxic tissue injury. In addition, recent data suggests that increased tissue lipids may also be protective in certain contexts. This review will highlight recent progress toward elucidating the relationship between nutrient oversupply, lipotoxicity, and cardiovascular dysfunction. The review will focus in two sections on the vasculature and cardiomyocytes respectively. PMID:23054891

  3. Computational model of cardiovascular function during orthostatic stress.

    PubMed

    Heldt, T; Shim, E B; Kamm, R D; Mark, R G

    2000-01-01

    Orthostatic intolerance following spaceflight remains a critical problem in the current life-science space program. The study presented in this paper is part of an ongoing effort to use mathematical models to investigate the effects of gravitational stresses on the cardiovascular system of normals and microgravity adapted individuals. We employ a twelve compartment lumped parameter representation of the hemodynamic system coupled to set-point models of the arterial baroreflex and the cardiopulmonary reflex to investigate the transient response of heart rate to orthostatic stress. We simulate current hypotheses concerning the mechanisms underlying post-spaceflight orthostatic intolerance over a range of physiologically reasonable values and compare the simulations to astronaut stand-test data pre- and post-flight. Furthermore, we explore the effects of a potential countermeasure. PMID:11806418

  4. Is the cardiovascular system a therapeutic target for cannabidiol?

    PubMed

    Stanley, Christopher P; Hind, William H; O'Sullivan, Saoirse E

    2013-02-01

    Cannabidiol (CBD) has beneficial effects in disorders as wide ranging as diabetes, Huntington's disease, cancer and colitis. Accumulating evidence now also suggests that CBD is beneficial in the cardiovascular system. CBD has direct actions on isolated arteries, causing both acute and time-dependent vasorelaxation. In vitro incubation with CBD enhances the vasorelaxant responses in animal models of impaired endothelium-dependent vasorelaxation. CBD protects against the vascular damage caused by a high glucose environment, inflammation or the induction of type 2 diabetes in animal models and reduces the vascular hyperpermeability associated with such environments. A common theme throughout these studies is the anti-inflammatory and anti-oxidant effect of CBD. In the heart, in vivo CBD treatment protects against ischaemia-reperfusion damage and against cardiomyopathy associated with diabetes. Similarly, in a different model of ischaemia-reperfusion, CBD has been shown to reduce infarct size and increase blood flow in animal models of stroke, sensitive to 5HT(1A) receptor antagonism. Although acute or chronic CBD treatment seems to have little effect on haemodynamics, CBD reduces the cardiovascular response to models of stress, applied either systemically or intracranially, inhibited by a 5HT(1A) receptor antagonist. In blood, CBD influences the survival and death of white blood cells, white blood cell migration and platelet aggregation. Taken together, these preclinical data appear to support a positive role for CBD treatment in the heart, and in peripheral and cerebral vasculature. However, further work is required to strengthen this hypothesis, establish mechanisms of action and whether similar responses to CBD would be observed in humans. PMID:22670794

  5. Simulation of the human cardiovascular system for real-time physical interaction with an assist device

    Microsoft Academic Search

    Ben M. Hanson; Martin C. Levesley; Kevin Watterson; P. G. Walker

    2005-01-01

    In the development of left ventricular assist devices (LVADs), numerical simulations of the cardiovascular (CV) system have been widely used. Further, electrohydraulic simulations have been developed to evaluate the performance of a physical LVAD prototype against a numerical model of the CV system. The effects of dynamic cardiac compression (DCC) have been less well modeled. This paper considers the interaction

  6. [Changes in the cardiovascular system in selected endocrinopathies in children].

    PubMed

    Semeran, Kornel; Bossowski, Artur

    2011-01-01

    Hormones have influence on many tissues and organs including the cardiovascular system. This article analyzes fluctuations that happen in a child's cardiovascular system in selected endocrinopathies. We are pointing out the higher risk, in the course of diabetes, of development of arterial hypertension and atherosclerosis including participating mechanisms in their pathogenesis - disorders of the lipid metabolism, hiperinsulinaemia, insulin resistance or/and autonomic neuropathy. We are describing how the increased and reduced action of thyroid hormones on certain molecular pathways in the heart and vasculature causes relevant cardiovascular derangement. In the article, we are signaling also that the cardiovascular consequences of cortisol excess are elevation of blood pressure, obesity, hyperinsulinemia and/or dyslipidemia. This review analyzes the relationship of cortisol excess to these cardiovascular risk factors and to putative mechanisms for hypertension. In reference to clinical studies we are describing how the deficiency of the growth hormone is connected with a development of risk factors of cardiovascular diseases. In conclusion we underlined that early diagnosis and proper treatment of illnesses of the endocrine system can protect our pediatric patients from serious cardiac complications in later years. PMID:21489356

  7. Physiological system integrations with emphasis on the respiratory-cardiovascular system

    NASA Technical Reports Server (NTRS)

    Gallagher, R. R.

    1975-01-01

    The integration of two types of physiological system simulations is presented. The long term model is a circulatory system model which simulates long term blood flow variations and compartmental fluid shifts. The short term models simulate transient phenomena of the respiratory, thermoregulatory, and pulsatile cardiovascular systems as they respond to stimuli such as LBNP, exercise, and environmental gaseous variations. An overview of the interfacing approach is described. Descriptions of the variable interface for long term to short term and between the three short term models are given.

  8. The Role of Shear Stress on ET-1, KLF2, and NOS-3 Expression in the Developing Cardiovascular System of Chicken Embryos in a Venous Ligation Model

    NSDL National Science Digital Library

    2007-12-01

    In this review, the role of wall shear stress in the chicken embryonic heart is analyzed to determine its effect on cardiac development through regulating gene expression. Therefore, background information is provided for fluid dynamics, normal chicken and human heart development, cardiac malformations, cardiac and vitelline blood flow, and a chicken model to induce cardiovascular anomalies. A set of endothelial shear stress-responsive genes coding for endothelin-1 (ET-1), lung Krüppel-like factor (LKLF/KLF2), and endothelial nitric oxide synthase (eNOS/NOS-3) are active in development and are specifically addressed.

  9. Large Blood Vessels 1.1 Introduction --The Cardiovascular System

    E-print Network

    Luo, Xiaoyu

    Chapter 1 Large Blood Vessels 1.1 Introduction -- The Cardiovascular System The heart is a pump that circulates blood to the lungs for oxygenation (pul- monary circulation) and then throughout the systemic arterial system with a total cycle time of about one minute. From the left ventricle of the heart, blood

  10. Cardiovascular and nervous system changes during meditation

    PubMed Central

    Steinhubl, Steven R.; Wineinger, Nathan E.; Patel, Sheila; Boeldt, Debra L.; Mackellar, Geoffrey; Porter, Valencia; Redmond, Jacob T.; Muse, Evan D.; Nicholson, Laura; Chopra, Deepak; Topol, Eric J.

    2015-01-01

    Background: A number of benefits have been described for the long-term practice of meditation, yet little is known regarding the immediate neurological and cardiovascular responses to meditation. Wireless sensor technology allows, for the first time, multi-parameter and quantitative monitoring of an individual's responses during meditation. The present study examined inter-individual variations to meditation through continuous monitoring of EEG, blood pressure, heart rate and its variability (HRV) in novice and experienced meditators. Methods: Participants were 20 experienced and 20 novice meditators involved in a week-long wellness retreat. Monitoring took place during meditation sessions on the first and last full days of the retreat. All participants wore a patch that continuously streamed ECG data, while half of them also wore a wireless EEG headset plus a non-invasive continuous blood pressure monitor. Results: Meditation produced variable but characteristic EEG changes, significantly different from baseline, even among novice meditators on the first day. In addition, although participants were predominately normotensive, the mean arterial blood pressure fell a small (2–3 mmHg) but significant (p < 0.0001) amount during meditation. The effect of meditation on HRV was less clear and influenced by calculation technique and respiration. No clear relationship between EEG changes, HRV alterations, or mean blood pressure during meditation was found. Conclusion: This is the first study to investigate neurological and cardiovascular responses during meditation in both novice and experienced meditators using novel, wearable, wireless devices. Meditation produced varied inter-individual physiologic responses. These results support the need for further investigation of the short- and long-term cardiovascular effects of mental calm and individualized ways to achieve it. PMID:25852526

  11. Bench to Bedside Primer: The Cardiovascular System and Hypertension

    NSDL National Science Digital Library

    Jannette Moehlman (Dakota Middle School)

    2011-10-07

    This bench-to-bedside is a four-page Â?primerÂ? (a booklet of basic principles) that highlights cardiovascular physiology. This primer should be readable by your students or the general public to help inform them about the organ system, diseases that affect it, and basic and clinical research being done on it. It could also be used as a teaching model your students could follow in creating their own bench-to-beside primer.This teaching resource was developed by a K-12 science teacher in the American Physiological SocietyÂ?s 2011 Frontiers Online in Physiology Program. For more information on this program, please visit www.frontiersinphys.org.

  12. Effects of apelin on the cardiovascular system.

    PubMed

    Folino, Anna; Montarolo, Pier Giorgio; Samaja, Michele; Rastaldo, Raffaella

    2015-07-01

    Apelin is an endogenous peptide acting on the APJ receptor. It consists of several isoforms characterized by different numbers of amino acids. The number of amino acids in the active isoforms range from 36 to 12. Apelin-13 and, to a lesser extent, apelin-36 are considered the most active isoforms with the greatest activity on the cardiovascular homeostasis. The effects normally exerted by the basal level of endogenous apelin can be enhanced not only by its up-regulation, but may also by its exogenous administration. The present review considers the effects of apelin on various aspects of the cardiovascular function, such as cardiac development, vasomotor tone, angiogenesis, myocardial inotropy in healthy and failing hearts as well as the prevention of ischemia-reperfusion injury, cardiac fibrosis and remodeling. Also the biphasic changes in apelin level during the evolution of heart failure are considered. Although the positive inotropic effect exerted by apelin in normal and failing hearts would suggest the use of this peptide in the treatment of heart failure, the limited duration and extent of its effect do not support this possibility, unless a long-lasting (6 h) infusion is performed to overcome the limit of its short life. However, although the data on the characteristics of the inotropic activity do not provide a strong support for the treatment of active heart failure, apelin may be used in the prevention of heart failure because of its activity in limiting the consequences of myocardial ischemia such as infarct size and cardiac remodeling. PMID:25652330

  13. Computational modeling of cardiovascular response to orthostatic stress

    NASA Technical Reports Server (NTRS)

    Heldt, Thomas; Shim, Eun B.; Kamm, Roger D.; Mark, Roger G.

    2002-01-01

    The objective of this study is to develop a model of the cardiovascular system capable of simulating the short-term (< or = 5 min) transient and steady-state hemodynamic responses to head-up tilt and lower body negative pressure. The model consists of a closed-loop lumped-parameter representation of the circulation connected to set-point models of the arterial and cardiopulmonary baroreflexes. Model parameters are largely based on literature values. Model verification was performed by comparing the simulation output under baseline conditions and at different levels of orthostatic stress to sets of population-averaged hemodynamic data reported in the literature. On the basis of experimental evidence, we adjusted some model parameters to simulate experimental data. Orthostatic stress simulations are not statistically different from experimental data (two-sided test of significance with Bonferroni adjustment for multiple comparisons). Transient response characteristics of heart rate to tilt also compare well with reported data. A case study is presented on how the model is intended to be used in the future to investigate the effects of post-spaceflight orthostatic intolerance.

  14. Recipes for Creating Animal Models of Diabetic Cardiovascular Disease

    Microsoft Academic Search

    Karin E. Bornfeldt; Willa Hsueh; E. Dale Abel; Jan L. Breslow; Nobuyo Maeda; Richard C. Davis; Edward A. Fisher; Hayes Dansky; Donald A. McClain; Richard McIndoe; Momtaz K. Wassef; Cristina Rabadan-Diehl; Ira J. Goldberg

    2010-01-01

    For more than 50 years, investigators have unsuccessfully tried to recreate in experimental animals the cardiovascular complications of diabetes seen in humans. In particular, accelerated atherosclerosis and dilated cardiomyopathy, the major causes of mortality in patients with diabetes, have been conspicuously absent in many mouse models of the disease. Under the auspices of the NIH, the Animal Models of Diabetic

  15. Developing through a Modeling of the Database: an Implementation of PEP for Cardiovascular Monitoring

    Microsoft Academic Search

    Hugo Bulegon; Silvio Bortoleto; Angelmar Constantino Roman

    2009-01-01

    The modeling data is very important in building systems, it gives an idea of the complete operation and helps in the process of mining data. From this information, a system was developed to facilitate the clinical management in primary health care, improving efficiency in reducing the morbidity and mortality. The software is focused on major cardiovascular risk factors: diabetes, hypertension,

  16. Obesity May Shut Down Circadian Clock in the Cardiovascular System

    NSDL National Science Digital Library

    APS Communications Office (American Physiological Society Communications Office)

    2011-04-10

    Researchers at the Georgia Health Sciences University in Augusta have found that a master clock gene Â? which regulates the cardiovascular system Â? does not fluctuate regularly as it does in non-obese animals. This means that a key gene clock of the cardiovascular system does not work properly when obesity is present. These findings are believed to be the first of their kind. The study was conducted by Shuiqing Qiu, Eric Belin de Chantemele, James Mintz, David J. Fulton, R. Daniel Rudic and David W. Stepp.

  17. Clinical Application of Stem Cells in the Cardiovascular System

    NASA Astrophysics Data System (ADS)

    Stamm, Christof; Klose, Kristin; Choi, Yeong-Hoon

    Regenerative medicine encompasses "tissue engineering" - the in vitro fabrication of tissues and/or organs using scaffold material and viable cells - and "cell therapy" - the transplantation or manipulation of cells in diseased tissue in vivo. In the cardiovascular system, tissue engineering strategies are being pursued for the development of viable replacement blood vessels, heart valves, patch material, cardiac pacemakers and contractile myocardium. Anecdotal clinical applications of such vessels, valves and patches have been described, but information on systematic studies of the performance of such implants is not available, yet. Cell therapy for cardiovascular regeneration, however, has been performed in large series of patients, and numerous clinical studies have produced sometimes conflicting results. The purpose of this chapter is to summarize the clinical experience with cell therapy for diseases of the cardiovascular system, and to analyse possible factors that may influence its outcome.

  18. Contraceptive Steroids, age, and the cardiovascular system.

    PubMed

    Plunkett, E R

    1982-03-15

    There is evidence that women who use oral contraceptives may be at slightly greater risk of cardiovascular complications as their age increased beyond 35 years. Popular opinion has held that these risks were largely estrogen-related. At the same time, however, postmenopausal women taking natural estrogen alone or in association with minimal amounts of progestogen have not exhibited these increased risk when compared with untreated control subjects. New clinical data indicate that there is a progestogen dose-related decrease in high-density lipoprotein cholesterol. There is also some evidence that relates progestogen dosage to morbidity rates from circulatory disease. Therefore the smallest dose of both estrogen and progestogen consistent with contraceptive efficacy and reasonable cycle control must be sought for all steroid combinations. This applies particularly to oral contraception for the woman beyond 35 years of age. PMID:7065055

  19. A Genomic-Systems Biology Map for Cardiovascular Function

    Microsoft Academic Search

    Monika Stoll; Allen W. Cowley; Peter J. Tonellato; Andrew S. Greene; Mary L. Kaldunski; Richard J. Roman; Pierre Dumas; Nicholas J. Schork; Zhitao Wang; Howard J. Jacob

    2001-01-01

    With the draft sequence of the human genome available, there is a need to better define gene function in the context of systems biology. We studied 239 cardiovascular and renal phenotypes in 113 male rats derived from an F2 intercross and mapped 81 of these traits onto the genome. Aggregates of traits were identified on chromosomes 1, 2, 7, and

  20. Electronic circuit detects left ventricular ejection events in cardiovascular system

    NASA Technical Reports Server (NTRS)

    Gebben, V. D.; Webb, J. A., Jr.

    1972-01-01

    Electronic circuit processes arterial blood pressure waveform to produce discrete signals that coincide with beginning and end of left ventricular ejection. Output signals provide timing signals for computers that monitor cardiovascular systems. Circuit operates reliably for heart rates between 50 and 200 beats per minute.

  1. Hydroxybenzoic acid isomers and the cardiovascular system.

    PubMed

    Juurlink, Bernhard H J; Azouz, Haya J; Aldalati, Alaa M Z; AlTinawi, Basmah M H; Ganguly, Paul

    2014-01-01

    Today we are beginning to understand how phytochemicals can influence metabolism, cellular signaling and gene expression. The hydroxybenzoic acids are related to salicylic acid and salicin, the first compounds isolated that have a pharmacological activity. In this review we examine how a number of hydroxyphenolics have the potential to ameliorate cardiovascular problems related to aging such as hypertension, atherosclerosis and dyslipidemia. The compounds focused upon include 2,3-dihydroxybenzoic acid (Pyrocatechuic acid), 2,5-dihydroxybenzoic acid (Gentisic acid), 3,4-dihydroxybenzoic acid (Protocatechuic acid), 3,5-dihydroxybenzoic acid (?-Resorcylic acid) and 3-monohydroxybenzoic acid. The latter two compounds activate the hydroxycarboxylic acid receptors with a consequence there is a reduction in adipocyte lipolysis with potential improvements of blood lipid profiles. Several of the other compounds can activate the Nrf2 signaling pathway that increases the expression of antioxidant enzymes, thereby decreasing oxidative stress and associated problems such as endothelial dysfunction that leads to hypertension as well as decreasing generalized inflammation that can lead to problems such as atherosclerosis. It has been known for many years that increased consumption of fruits and vegetables promotes health. We are beginning to understand how specific phytochemicals are responsible for such therapeutic effects. Hippocrates' dictum of 'Let food be your medicine and medicine your food' can now be experimentally tested and the results of such experiments will enhance the ability of nutritionists to devise specific health-promoting diets. PMID:24943896

  2. Mutations affecting the formation and function of the cardiovascular system in the zebrafish embryo

    Microsoft Academic Search

    J N Chen; M A Mohideen; L Solnica-Krezel; A F Schier; J Malicki

    1996-01-01

    Abstract As part of a large-scale mutagenesis screen of the zebrafish genome, we have identified 58 mutations that affect the formation and function of the cardiovascular system. The cardiovascular system is

  3. Parasympathetic Stimuli on Bronchial and Cardiovascular Systems in Humans

    PubMed Central

    Zannin, Emanuela; Pellegrino, Riccardo; Di Toro, Alessandro; Antonelli, Andrea; Dellacà, Raffaele L.; Bernardi, Luciano

    2015-01-01

    Background It is not known whether parasympathetic outflow simultaneously acts on bronchial tone and cardiovascular system waxing and waning both systems in parallel, or, alternatively, whether the regulation is more dependent on local factors and therefore independent on each system. The aim of this study was to evaluate the simultaneous effect of different kinds of stimulations, all associated with parasympathetic activation, on bronchomotor tone and cardiovascular autonomic regulation. Methods Respiratory system resistance (Rrs, forced oscillation technique) and cardio-vascular activity (heart rate, oxygen saturation, tissue oxygenation index, blood pressure) were assessed in 13 volunteers at baseline and during a series of parasympathetic stimuli: O2 inhalation, stimulation of the carotid sinus baroreceptors by neck suction, slow breathing, and inhalation of methacholine. Results Pure cholinergic stimuli, like O2 inhalation and baroreceptors stimulation, caused an increase in Rrs and a reduction in heart rate and blood pressure. Slow breathing led to bradycardia and hypotension, without significant changes in Rrs. However slow breathing was associated with deep inhalations, and Rrs evaluated at the baseline lung volumes was significantly increased, suggesting that the large tidal volumes reversed the airways narrowing effect of parasympathetic activation. Finally inhaled methacholine caused marked airway narrowing, while the cardiovascular variables were unaffected, presumably because of the sympathetic activity triggered in response to hypoxemia. Conclusions All parasympathetic stimuli affected bronchial tone and moderately affected also the cardiovascular system. However the response differed depending on the nature of the stimulus. Slow breathing was associated with large tidal volumes that reversed the airways narrowing effect of parasympathetic activation. PMID:26046774

  4. The Representative Porcine Model for Human Cardiovascular Disease

    PubMed Central

    Suzuki, Yoriyasu; Yeung, Alan C.; Ikeno, Fumiaki

    2011-01-01

    To improve human health, scientific discoveries must be translated into practical applications. Inherent in the development of these technologies is the role of preclinical testing using animal models. Although significant insight into the molecular and cellular basis has come from small animal models, significant differences exist with regard to cardiovascular characteristics between these models and humans. Therefore, large animal models are essential to develop the discoveries from murine models into clinical therapies and interventions. This paper will provide an overview of the more frequently used large animal models, especially porcine models for preclinical studies. PMID:21253493

  5. Differential Role of Leptin and Adiponectin in Cardiovascular System

    PubMed Central

    Ghantous, C. M.; Azrak, Z.; Hanache, S.; Abou-Kheir, W.; Zeidan, A.

    2015-01-01

    Leptin and adiponectin are differentially expressed adipokines in obesity and cardiovascular diseases. Leptin levels are directly associated with adipose tissue mass, while adiponectin levels are downregulated in obesity. Although significantly produced by adipocytes, leptin is also produced by vascular smooth muscle cells and cardiomyocytes. Plasma leptin concentrations are elevated in cases of cardiovascular diseases, such as hypertension, congestive heart failure, and myocardial infarction. As for the event of left ventricular hypertrophy, researchers have been stirring controversy about the role of leptin in this form of cardiac remodeling. In this review, we discuss how leptin has been shown to play an antihypertrophic role in the development of left ventricular hypertrophy through in vitro experiments, population-based cross-sectional studies, and longitudinal cohort studies. Conversely, we also examine how leptin may actually promote left ventricular hypertrophy using in vitro analysis and human-based univariate and multiple linear stepwise regression analysis. On the other hand, as opposed to leptin's generally detrimental effects on the cardiovascular system, adiponectin is a cardioprotective hormone that reduces left ventricular and vascular hypertrophy, oxidative stress, and inflammation. In this review, we also highlight adiponectin signaling and its protective actions on the cardiovascular system.

  6. Patient-specific modeling of cardiovascular and respiratory dynamics during hypercapnia

    PubMed Central

    Ellwein, L.M.; Pope, S.R.; Xie, A.; Batzel, J.J.; Kelley, C.T.; Olufsen, M.S.

    2014-01-01

    This study develops a lumped cardiovascular-respiratory system-level model that incorporates patient-specific data to predict cardiorespiratory response to hyper-capnia (increased CO2 partial pressure) for a patient with congestive heart failure (CHF). In particular, the study focuses on predicting cerebral CO2 reactivity, which can be defined as the ability of vessels in the cerebral vasculature to expand or contract in response CO2 induced challenges. It is difficult to characterize cerebral CO2 reactivity directly from measurements, since no methods exist to dynamically measure vasomotion of vessels in the cerebral vasculature. In this study we show how mathematical modeling can be combined with available data to predict cerebral CO2 reactivity via dynamic predictions of cerebral vascular resistance, which can be directly related to vasomotion of vessels in the cerebral vasculature. To this end we have developed a coupled cardiovascular and respiratory model that predicts blood pressure, flow, and concentration of gasses (CO2 and O2) in the systemic, cerebral, and pulmonary arteries and veins. Cerebral vascular resistance is incorporated via a model parameter separating cerebral arteries and veins. The model was adapted to a specific patient using parameter estimation combined with sensitivity analysis and subset selection. These techniques allowed estimation of cerebral vascular resistance along with other cardiovascular and respiratory parameters. Parameter estimation was carried out during eucapnia (breathing room air), first for the cardiovascular model and then for the respiratory model. Then, hypercapnia was introduced by increasing inspired CO2 partial pressure. During eucapnia, 7 cardiovascular parameters and 4 respiratory parameters was be identified and estimated, including cerebral and systemic resistance. During the transition from eucapnia to hypercapnia, the model predicted a drop in cerebral vascular resistance consistent with cerebral vasodilation. PMID:23046704

  7. Method of Propulsion of a Ferromagnetic Core in the Cardiovascular System Through Magnetic Gradients Generated by an MRI System

    Microsoft Academic Search

    Jean-Baptiste Mathieu; Gilles Beaudoin; Sylvain Martel

    2006-01-01

    This paper reports the use of a magnetic resonance imaging (MRI) system to propel a ferromagnetic core. The con- cept was studied for future development of microdevices designed to perform minimally invasive interventions in remote sites acces- sible through the human cardiovascular system. A mathematical model is described taking into account various parameters such as the size of blood vessels,

  8. Method of propulsion of a ferromagnetic core in the cardiovascular system through magnetic gradients generated by an MRI system

    Microsoft Academic Search

    Jean-Baptiste Mathieu; Gilles Beaudoin; Sylvain Martel

    2006-01-01

    This paper reports the use of a magnetic resonance imaging (MRI) system to propel a ferromagnetic core. The concept was studied for future development of microdevices designed to perform minimally invasive interventions in remote sites accessible through the human cardiovascular system. A mathematical model is described taking into account various parameters such as the size of blood vessels, the velocities

  9. Hardware-in-the-loop-simulation of the cardiovascular system, with assist device testing application.

    PubMed

    Hanson, B M; Levesley, M C; Watterson, K; Walker, P G

    2007-04-01

    This paper presents a technique for evaluating the performance of biomedical devices by combining physical (mechanical) testing with a numerical, computerised model of a biological system. This technique is developed for evaluation of a cardiac assist device prior to in vivo trials. This device will wrap around a failing heart and provide physical beating assistance (dynamic cardiac compression). In vitro, the device to be tested is placed around a simulator comprising a mechanical simulation of the beating ventricles. This hardware model interfaces with a computerised (software) model of the cardiovascular system. In real time the software model calculates the effect of the assistance on the cardiovascular system and controls the beating motion of the hardware heart simulator appropriately. The software model of the cardiovascular system can represent ventricles in various stages of heart failure, and/or hardened or congested blood vessels as required. The software displays physiological traces showing the cardiac output, depending on the natural function of the modelled heart together with the physical assist power provided. This system was used to evaluate the effectiveness of control techniques applied to the assist device. Experimental results are presented showing the efficacy of prototype assist on healthy and weakened hearts, and the effect of asynchronous assist. PMID:16815728

  10. Human Induced Pluripotent Stem Cell Models of Inherited Cardiovascular Diseases.

    PubMed

    Jiang, Wenjian; Lan, Feng; Zhang, Hongjia

    2014-10-16

    Cardiovascular cells derived from patient specific induced Pluripotent Stem Cell (iPSC) harbor gene mutations associated with the pathogenesis of inherited cardiac diseases and congenital heart diseases (CHD). Numerous reports have demonstrated the utilization of human induced Pluripotent Stem Cell (hiPSC) to model cardiac diseases as a means of investigating their underlying mechanisms. So far, they have been shown to investigate the molecular mechanisms of many cardiac disorders, such as long-QT syndrome (LQT), catecholaminergic polymorphic ventricular tachycardia (CPVT), dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), LEOPARD syndrome (LS), arrhythmogenic cardiomyopathy (ACM), Friedreich ataxia (FRDA), Barth syndrome (BTHS), hypoplastic left heart syndrome (HLHS), Marfan syndrome (MFS) and other CHD. This article summarizes the growing body of research related to modeling various cardiac diseases using hiPSCs. Moreover, by reviewing the methods used in previous studies, we propose multiple novel applications of hiPSCs to investigate comprehensive cardiovascular disorders and facilitate drug discovery. PMID:25322695

  11. Clinical Application of Stem Cells in the Cardiovascular System

    Microsoft Academic Search

    Christof Stamm; Kristin Klose; Yeong-Hoon Choi

    2010-01-01

    \\u000a Regenerative medicine encompasses “tissue engineering” – the in vitro fabrication of tissues and\\/or organs using scaffold\\u000a material and viable cells – and “cell therapy” – the transplantation or manipulation of cells in diseased tissue in vivo.\\u000a In the cardiovascular system, tissue engineering strategies are being pursued for the development of viable replacement blood\\u000a vessels, heart valves, patch material, cardiac pacemakers

  12. Therapy Insight: cardiovascular disease in pediatric systemic lupus erythematosus

    Microsoft Academic Search

    Stacy P Ardoin; Laura Schanberg; Christy Sandborg

    2008-01-01

    In 15–20% of cases, systemic lupus erythematosus (SLE) presents before the age of 18 years, and such early-onset SLE seems to be particularly severe. SLE is an independent risk factor for premature atherosclerosis and death in young, premenopausal women with SLE, even after controlling for traditional cardiovascular risk factors. Children and adolescents with SLE are particularly susceptible to this long-term

  13. Risk Factors for Cardiovascular Disease in Systemic Lupus Erythematosus

    Microsoft Academic Search

    Elisabet Svenungsson; Kerstin Jensen-Urstad; Mikael Heimbürger; Angela Silveira; Anders Hamsten; Joseph L. Witztum; Johan Frostegård

    2010-01-01

    Background—Cardiovascular disease (CVD) is overrepresented in patients with systemic lupus erythematosus (SLE). We determined the prevalence of traditional and nontraditional risk factors for CVD in SLE patients with and without CVD compared with controls. Methods and Results—Twenty-six women (aged 528.2 years) with SLE and a history of CVD (SLE cases) were compared with 26 age-matched women with SLE but without

  14. Redox modification of cell signaling in the cardiovascular system

    PubMed Central

    Shao, Dan; Oka, Shin-ichi; Brady, Christopher D.; Haendeler, Judith; Eaton, Philip; Sadoshima, Junichi

    2011-01-01

    Oxidative stress is presumed to be involved in the pathogenesis of many diseases, including cardiovascular disease. However, oxidants are also generated in healthy cells, and increasing evidence suggests that they can work as signaling molecules. Intracellular reduction-oxidation (redox) status is tightly regulated by oxidant and antioxidant systems. Imbalance between them causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, leading to dysregulation. In this review, we will briefly summarize the aspects of ROS generation and neutralization mechanisms in the cardiovascular system. ROS can regulate cell signaling through oxidation and reduction of specific amino acids within proteins. Structural changes during post-translational modification allow modification of protein activity which can result in alteration of cellular function. We will focus on the molecular basis of redox protein modification and how this regulatory mechanism affects signal transduction in the cardiovascular system. Finally, we will discuss some techniques applied to monitoring redox status and identifying redox-sensitive proteins in the heart. PMID:21945521

  15. Redox modification of cell signaling in the cardiovascular system.

    PubMed

    Shao, Dan; Oka, Shin-ichi; Brady, Christopher D; Haendeler, Judith; Eaton, Philip; Sadoshima, Junichi

    2012-03-01

    Oxidative stress is presumed to be involved in the pathogenesis of many diseases, including cardiovascular disease. However, oxidants are also generated in healthy cells, and increasing evidence suggests that they can act as signaling molecules. The intracellular reduction-oxidation (redox) status is tightly regulated by oxidant and antioxidant systems. Imbalance between them causes oxidative or reductive stress which triggers cellular damage or aberrant signaling, leading to dysregulation. In this review, we will briefly summarize the aspects of ROS generation and neutralization mechanisms in the cardiovascular system. ROS can regulate cell signaling through oxidation and reduction of specific amino acids within proteins. Structural changes during post-translational modification allow modification of protein activity which can result in altered cellular function. We will focus on the molecular basis of redox protein modification and how this regulatory mechanism affects signal transduction in the cardiovascular system. Finally, we will discuss some techniques applied to monitoring redox status and identifying redox-sensitive proteins in the heart. This article is part of a Special Section entitled "Post-translational Modification." PMID:21945521

  16. Rational macromodeling of 1D blood flow in the human cardiovascular system.

    PubMed

    Ferranti, Francesco; Tamburrelli, Vincenzopio; Antonini, Giulio

    2015-03-01

    In this paper, we present a novel rational macromodeling approach for the description of 1D blood flow in the human cardiovascular system, which is suitable for time-domain simulations. Using the analogy of the blood flow propagation problem with transmission lines and considering the hypothesis of linearized Navier-Stokes equations, a frequency-domain rational macromodel for each arterial segment has been built. The poles and the residues of each arterial segment macromodel have been calculated by means of the Vector Fitting technique. Finally, the rational macromodel of the whole cardiovascular system is obtained by properly combining the macromodels of the single arterial segments using an interconnect matrix. The rational form of the proposed cardiovascular model leads to a state-space or electrical circuit model suitable for time-domain analysis. The stability and passivity properties of the global cardiovascular model are discussed to guarantee stable time-domain simulations. The proposed macromodeling approach has been validated by pertinent numerical results. Copyright © 2015?John Wiley & Sons, Ltd. PMID:25656004

  17. Perspectives of induced pluripotent stem cells for cardiovascular system regeneration.

    PubMed

    Csöbönyeiová, Mária; Polák, Štefan; Danišovi?, L'uboš

    2015-05-01

    Induced pluripotent stem cells (iPSCs) hold great promise for basic research and regenerative medicine. They offer the same advantages as embryonic stem cells (ESCs) and moreover new perspectives for personalized medicine. iPSCs can be generated from adult somatic tissues by over-expression of a few defined transcription factors, including Oct4, Sox2, Klf4, and c-myc. For regenerative medicine in particular, the technology provides great hope for patients with incurable diseases or potentially fatal disorders such as heart failure. The endogenous regenerative potentials of adult hearts are extremely limited and insufficient to compensate for myocardial loss occurring after myocardial infarction. Recent discoveries have demonstrated that iPSCs have the potential to significantly advance future cardiovascular regenerative therapies. Moreover, iPSCs can be generated from somatic cells of patients with genetic basis for their disease. This human iPSC derivates offer tremendous potential for new disease models. This paper reviews current applications of iPSCs in cardiovascular regenerative medicine and discusses progress in modeling cardiovascular diseases using iPSCs-derived cardiac cells. PMID:25595188

  18. The human cardiovascular system in the absence of gravity

    NASA Technical Reports Server (NTRS)

    Bungo, M. W.; Charles, J. B.

    1985-01-01

    The data collected from a Space Shuttle crew to investigate cardiovascular changes due to microgravity are presented. The experimental procedures which involved preflight, immediate postflight, and one week following postflight echocardiograms of 13 individuals are described. The immediate postflight results reveal a 20 percent decrease in stroke volume, a 16 percent decrease in left ventricular diastolic volume index (LVDVI), no change in systolic volume, blood pressure, or cardiac index, and a 24 percent increase in heart rate. One week later a 17 percent stroke volume increase, a 29 percent increase in cardiac index, and normal blood pressure, and LVDVI were observed. It is concluded that upon reexposure to gravity a readaptation process for the cardiovascular system occurs.

  19. Efficient anisotropic adaptive discretization of the cardiovascular system O. Sahni a,*, J. Muller a

    E-print Network

    Frey, Pascal

    , a challenging but important quantity in the understanding of cardiovascular disease. The general anisotropicEfficient anisotropic adaptive discretization of the cardiovascular system O. Sahni a,*, J. Mu how computational efficiency can be increased when applying it to the simulation of cardiovascular

  20. Mathematical modeling of acute and chronic cardiovascular changes during Extended Duration Orbiter (EDO) flights.

    PubMed

    White, R J; Leonard, J I; Srinivasan, R S; Charles, J B

    1991-01-01

    The Extended Duration Orbiter (EDO) program aims to extend the capability of the Shuttle orbiter beyond its current 7-10 day limit on mission duration. This goal is to be accomplished in steps, partly due to our limited knowledge of the physiological changes resulting from long-term exposure to weightlessness and their likely influence on critical mission operations involved in EDO flights. Answers to questions related to physiologic adaptation to weightlessness are being actively sought at the present time to help implement the EDO program. In the cardiovascular area, the loss of orthostatic tolerance is a medical concern because of its potential adverse effects on crew performance and safety during reentry and following return to earth. Flight and ground-based physiologic studies are being planned to understand the mechanism and time course of spaceflight-induced orthostatic intolerance and to develop effective countermeasures for improving post-flight cardiovascular performance. Where feasible, these studies are aided by theoretical analyses using mathematical modeling and computer simulation of physiological systems. This paper is concerned with the application of proven models of circulatory and cardiovascular systems in the analysis of chronic cardiovascular changes under weightless conditions. PMID:11537147

  1. Sex and the Cardiovascular System: The Intriguing Tale of How Women and Men Regulate Cardiovascular Function Differently

    NSDL National Science Digital Library

    PhD Virginia H. Huxley (University of Missouri School of Medicine Department of Medical Pharmacology and Physiology)

    2007-03-01

    The ability to recognize and appreciate from a reproductive standpoint that males and females possess different attributes has been long standing. Only more recently have we begun to look more deeply into both the similarities and differences between men and women, as well as between boys and girls, with respect to the structure and function of other organ systems. This article focuses on the cardiovascular system, with examples of sex differences in the control of coronary function, blood pressure, and volume. Recognizing the differences between the sexes with respect to cardiovascular function facilitates understanding of the mechanisms whereby homeostasis can be achieved using different contributions or components of the living system. Furthermore, recognition of the differences as well as the similarities permits the design of appropriate diagnostic instruments, recognition of sex-specific pathophysiology, and implementation of appropriate treatment of cardiovascular disease in men and women.

  2. Consequences of Circadian and Sleep Disturbances for the Cardiovascular System.

    PubMed

    Alibhai, Faisal J; Tsimakouridze, Elena V; Reitz, Cristine J; Pyle, W Glen; Martino, Tami A

    2015-07-01

    Circadian rhythms play a crucial role in our cardiovascular system. Importantly, there has been a recent flurry of clinical and experimental studies revealing the profound adverse consequences of disturbing these rhythms on the cardiovascular system. For example, circadian disturbance worsens outcome after myocardial infarction with implications for patients in acute care settings. Moreover, disturbing rhythms exacerbates cardiac remodelling in heart disease models. Also, circadian dyssynchrony is a causal factor in the pathogenesis of heart disease. These discoveries have profound implications for the cardiovascular health of shift workers, individuals with circadian and sleep disorders, or anyone subjected to the 24/7 demands of society. Moreover, these studies give rise to 2 new frontiers for translational research: (1) circadian rhythms and the cardiac sarcomere, which sheds new light on our understanding of myofilament structure, signalling, and electrophysiology; and (2) knowledge translation, which includes biomarker discovery (chronobiomarkers), timing of therapies (chronotherapy), and other new promising approaches to improve the management and treatment of cardiovascular disease. Reconsidering circadian rhythms in the clinical setting benefits repair mechanisms, and offers new promise for patients. PMID:26031297

  3. Anthrax toxin: pathologic effects on the cardiovascular system.

    PubMed

    Golden, Honey B; Watson, Linley E; Lal, Hind; Verma, Suresh K; Foster, Donald M; Kuo, Shu-Ru; Sharma, Avadhesh; Frankel, Arthur; Dostal, David E

    2009-01-01

    Anthrax is a disease caused by infection with spores from the bacteria Bacillus anthracis. After entering the body, the spores germinate into bacteria and secrete a toxin that causes local edema and, in systemic infections, cardiovascular collapse and death. The toxin is a tripartite polypeptide, consisting of protective antigen (PA), lethal factor (LF) and edema factor (EF), which have key roles in the bacterial pathogenesis and disease progression. PA facilitates transfer of LF and EF to the cytosol. Lethal toxin is a zinc metalloproteinase, which has the capacity to inactivate mitogen-activated protein (MAP) kinase kinase (MEK) and stimulates the release of sepsis-related cytokines tumor necrosis factor-alpha and interleukin-1beta. Edema factor is a calmodulin (CaM)-dependent adenylate cyclase, which increases levels of cyclic AMP, causing impaired neutrophil function and disruption of water balance that ultimately results in massive tissue edema. Together, the toxins effectively inhibit host innate and adaptive immune responses, allowing the bacteria to grow unrestrained and overwhelming any resistance. Clinically, inhalational anthrax presents in a biphasic pattern with initial nonspecific "flu-like" symptoms nausea and vomiting 1 to 4 days after exposure, followed by severe illness with dyspnea, high fever and circulatory shock. The latter symptoms represent a terminal stage and treatment is often ineffective when started at that time. Key indicators of early anthrax cardiovascular-related pathogenesis include mediastinal widening in association with pleural effusion and edema. In this review, we describe the current understanding of anthrax toxins on cellular function in the context of cardiovascular function and discuss potential therapeutic strategies. PMID:19273204

  4. Animal Models in Cardiovascular Diseases: New Insights from Conditional Models

    Microsoft Academic Search

    A. Nguyen Din Cat; Y. Sainte-Marie; F. Jaisser

    Conditional systems have proven to be efficient and powerful to delineate several aspects of cardiac pathophysiology and diseases. The possibility of addressing a particular time point in animal life is certainly an important breakthrough allowed by conditional strategies with temporal control of either transgene expression or gene modifications. The purpose of this review is to present various mouse models for

  5. Animal Models in Cardiovascular Research: Hypertension and Atherosclerosis

    PubMed Central

    Ng, Chun-Yi; Jaarin, Kamsiah

    2015-01-01

    Hypertension and atherosclerosis are among the most common causes of mortality in both developed and developing countries. Experimental animal models of hypertension and atherosclerosis have become a valuable tool for providing information on etiology, pathophysiology, and complications of the disease and on the efficacy and mechanism of action of various drugs and compounds used in treatment. An animal model has been developed to study hypertension and atherosclerosis for several reasons. Compared to human models, an animal model is easily manageable, as compounding effects of dietary and environmental factors can be controlled. Blood vessels and cardiac tissue samples can be taken for detailed experimental and biomolecular examination. Choice of animal model is often determined by the research aim, as well as financial and technical factors. A thorough understanding of the animal models used and complete analysis must be validated so that the data can be extrapolated to humans. In conclusion, animal models for hypertension and atherosclerosis are invaluable in improving our understanding of cardiovascular disease and developing new pharmacological therapies.

  6. Regulation of Chromatin Structure in the Cardiovascular System

    PubMed Central

    Rosa-Garrido, Manuel; Karbassi, Elaheh; Monte, Emma; Vondriska, Thomas M

    2013-01-01

    It has been appreciated for some time that cardiovascular disease involves large-scale transcriptional changes in various cell types. What has become increasingly clear only in the last few years, however, is the role of chromatin remodeling in cardiovascular phenotypes in normal physiology as well as in development and disease. This review summarizes the state of the chromatin field in terms of distinct mechanisms to regulate chromatin structure in vivo, identifying when these modes of regulation have been demonstrated in cardiovascular tissues. We describe areas in which a better understanding of chromatin structure is leading to new insights into the fundamental biology of cardiovascular disease. PMID:23575346

  7. Surveillance of cardiovascular diseases using a multivariate dynamic screening system.

    PubMed

    Qiu, Peihua; Xiang, Dongdong

    2015-06-30

    In the SHARe Framingham Heart Study of the National Heart, Lung and Blood Institute, one major task is to monitor several health variables (e.g., blood pressure and cholesterol level) so that their irregular longitudinal pattern can be detected as soon as possible and some medical treatments applied in a timely manner to avoid some deadly cardiovascular diseases (e.g., stroke). To handle this kind of applications effectively, we propose a new statistical methodology called multivariate dynamic screening system (MDySS) in this paper. The MDySS method combines the major strengths of the multivariate longitudinal data analysis and the multivariate statistical process control, and it makes decisions about the longitudinal pattern of a subject by comparing it with other subjects cross sectionally and by sequentially monitoring it as well. Numerical studies show that MDySS works well in practice. Copyright © 2015 John Wiley & Sons, Ltd. PMID:25757653

  8. Melatonin and clock genes expression in the cardiovascular system.

    PubMed

    Zeman, Michal; Herichova, Iveta

    2013-01-01

    Generation of circadian oscillations is based on rhythmic expression of clock genes and subsequent post-transcriptional and post-translational modifications. In addition to the central circadian oscillator - the suprachiasmatic nucleus (SCN), peripheral oscillators have been demonstrated in many tissues, including the heart and blood vessels. Melatonin mediates cyclic lighting conditions to rhythmic endocrine signal and is able to synchronize neuronal firing in the SCN via membrane receptors. Clock gene expression is melatonin sensitive in the pars tuberalis, genes cry1 and tim1 respond to single injection while neurod1 and npas4 are influenced via long lasting mechanisms. In the rat heart, melatonin phase advanced expression of per2 and bmal1 independently from its effects on the SCN. Melatonin is an important endogenous signal able to synchronize circadian oscillations in the cardiovascular system. It may be effective especially in situations when the circadian control is weakened or organism must adapt to rapid changes in rhythmic environmental conditions. PMID:23277083

  9. Risk Factors in Cardiovascular Disease in Systemic Lupus Erythematosus

    PubMed Central

    Sinicato, Nailú Angélica; Cardoso, Priscila Aparecida da Silva; Appenzeller, Simone

    2013-01-01

    Systemic lupus erythematosus (SLE) is a chronic and multisystemic autoimmune disorder which predominantly affecting women. The most common cause of death in SLE patients affected by disease for more than 5 years is cardiovascular disease (CVD). Epidemiological observations suggest that, together with classical conventional risk factors, other mechanisms (non-conventional/disease-specific factors) promote accelerated atherosclerosis in inflammatory diseases like SLE. Traditional CVD risk factors included age, hypertension, diabetes mellitus, dyslipidemia, previous vascular event defined as previous history of cerebrovascular accidents or ischemic heart disease, menopause and smoking. The non-traditional factors presents in SLE are disease-specific like renal disease manifestation as Lupus nephritis (LN), presence of pro-inflammatory cytokines, some of inflammatory mediators, antiphospholipid antibodies, anti-oxLDL antibodies, corticosteroid uses and cumulative dose of glucocorticoids. We will review traditional and non-traditional risk factors associated with CVD in SLE patients. PMID:23463953

  10. Monitoring and treating the cardiovascular system in neonatal foals

    Microsoft Academic Search

    Kevin T. T. Corley

    2003-01-01

    Hemodynamic disturbances are common in critically ill foals. Foals do not always show the expected protective physiological response to cardiovascular changes, which can delay the identification of problems and increase the associated morbidity and mortality. Overall cardiovascular function can be assessed by clinical examination, urine output, and markers of oxygen delivery such as pulse oximetry and markers of tissue oxygenation

  11. Neural Control of the Cardiovascular System in Space

    NASA Technical Reports Server (NTRS)

    Levine, Benjamin D.; Pawelczyk, James A.; Zuckerman, Julie; Zhang, Rong; Fu, Qi; Iwasaki, Kenichi; Ray, Chet; Blomqvist, C. Gunnar; Lane, Lynda D.; Giller, Cole A.

    2003-01-01

    During the acute transition from lying supine to standing upright, a large volume of blood suddenly moves from the chest into the legs. To prevent fainting, the blood pressure control system senses this change immediately, and rapidly adjusts flow (by increasing heart rate) and resistance to flow (by constricting the blood vessels) to restore blood pressure and maintain brain blood flow. If this system is inadequate, the brain has a backup plan. Blood vessels in the brain can adjust their diameter to keep blood flow constant. If blood pressure drops, the brain blood vessels dilate; if blood pressure increases, the brain blood vessels constrict. This process, which is called autoregulation, allows the brain to maintain a steady stream of oxygen, even when blood pressure changes. We examined what changes in the blood pressure control system or cerebral autoregulation contribute to the blood pressure control problems seen after spaceflight. We asked: (1) does the adaptation to spaceflight cause an adaptation in the blood pressure control system that impairs the ability of the system to constrict blood vessels on return to Earth?; (2) if such a defect exists, could we pinpoint the neural pathways involved?; and (3) does cerebral autoregulation become abnormal during spaceflight, impairing the body s ability to maintain constant brain blood flow when standing upright on Earth? We stressed the blood pressure control system using lower body negative pressure, upright tilt, handgrip exercise, and cold stimulation of the hand. Standard cardiovascular parameters were measured along with sympathetic nerve activity (the nerve activity causing blood vessels to constrict) and brain blood flow. We confirmed that the primary cardiovascular effect of spaceflight was a postflight reduction in upright stroke volume (the amount of blood the heart pumps per beat). Heart rate increased appropriately for the reduction in stroke volume, thereby showing that changes in heart rate regulation alone cannot be responsible for orthostatic hypotension after spaceflight. All of the astronauts in our study had an increase in sympathetic nerve activity during upright tilting on Earth postflight. This increase was well calibrated for the reduction in stroke volume induced by the upright posture. The results obtained from stimulating the sympathetic nervous system using handgrip exercise or cold stress were also entirely normal during and after spaceflight. No astronaut had reduced cerebral blood flow during upright tilt, and cerebral autoregulation was normal or even enhanced inflight. These experiments show that the cardiovascular adaptation to spaceflight does not lead to a defect in the regulation of blood vessel constriction via sympathetic nerve activity. In addition, cerebral autoregulation is well-maintained. It is possible that despite the increased sympathetic nerve activity, blood vessels did not respond with a greater degree of constriction than occurred preflight, possibly uncovering a limit of vasoconstrictor reserve.

  12. Temporal association between pulmonary and systemic effects of particulate matter in healthy and cardiovascular compromised rats.

    PubMed

    Kodavanti, Urmila P; Schladweiler, Mette C; Ledbetter, Allen D; Hauser, Russ; Christiani, David C; McGee, John; Richards, Judy R; Costa, Daniel L

    2002-10-25

    Exposure to particulate matter (PM) has been associated with increased morbidity and mortality among individuals with cardiovascular disease. It is hypothesized that systemic alterations occur concurrent to pulmonary injury/inflammation, and contribute to cardiac events in compromised hosts. We explored this hypothesis using a rat model for human hypertension and cardiovascular disease (spontaneously hypertensive, SH), and normotensive Wistar Kyoto (WKY) rats. SH and WKY rats (12-13 wk old) were exposed either intratracheally (IT; 0.0, 1.0, or 5.0 mg/kg in saline) or nose-only (15 mg/m(3) x 6 h/d x 3 d/wk x 1, 2 or 4 wk) to combustion source residual oil fly ash (ROFA) with low metal content, and examined 1, 2 or 4 d later. Bronchoalveolar lavage fluid (BALF) albumin and neutrophils increased (SH approximately equal WKY) at d 1 following ROFA IT. With inhalation exposure, both strains experienced progressive histological lung damage and increases in BALF albumin and neutrophils during 1 to 4 wk (SH > WKY). Acute lung injury from ROFA IT was temporally associated with increases in plasma fibrinogen in both strains, but only the SH rats responded to the acute 1-wk ROFA inhalation. Longer term (2 or 4 wk) ROFA caused progressive lung injury (SH > WKY), but did not sustain the increase in fibrinogen. BALF glutathione increased in a temporal fashion similar to fibrinogen; however, only WKY rats demonstrated this response. There was a small but consistent decrease in blood lymphocytes and an increase in blood neutrophils in SH rats exposed to ROFA acutely. In conclusion, acute PM exposure can provoke an acute systemic thrombogenic response associated with pulmonary injury/inflammation and oxidative stress in cardiovascular compromised rats. This evidence is consistent with greater cardiovascular events during acute PM episodes in compromised humans. PMID:12396868

  13. Laser Doppler flowmetry signals to quantify effects of isoflurane on the peripheral cardiovascular system of healthy rats

    E-print Network

    Chapeau-Blondeau, François

    the peripheral cardiovascular system. Our work, there- fore, aims at bringing information on this area, an halogenated volatile anesthetic, on the peripheral cardiovascular system. After having recorded laser Doppler of the modifications brought by pharmaco- logical agents on the cardiovascular system has become an active area

  14. A Simple Ballistocardiographic System for a Medical Cardiovascular Physiology Course

    NSDL National Science Digital Library

    Antonio Eblen-Zajjur (Universidad de Carabobo Departamento Ciencias Fisiológicas)

    2003-12-01

    Ballistocardiography is an old, noninvasive technique used to record the movements of the body synchronous with the heartbeat due to left ventricular pump activity. Despite the fact that this technique to measure cardiac output has been superseded by more advanced and precise techniques, it is useful for teaching cardiac cycle physiology in an undergraduate practical course because of its noninvasive application in humans, clear physiological and physiopathological analysis, and practical approach to considering cardiac output issues. In the present report, a simple, low cost, easy-to-build ballistocardiography system is implemented together with a theoretical and practical session that includes NewtonÂ?s laws, cardiac output, cardiac pump activity, anatomy and physiology of the vessel circulation, vectorial composition, and signal transduction, which makes cardiovascular physiology easy to understand and focuses on the study of cardiac output otherwise seen only with the help of computer simulation or echocardiography. The proposed system is able to record body displacement or force as ballistocardiography traces and its changes caused by different physiological factors. The ballistocardiography session was included in our medical physiology course six years ago with very high acceptance and approval rates from the students.

  15. Theory and Developments in an Unobtrusive Cardiovascular System Representation: Ballistocardiography

    PubMed Central

    Pinheiro, Eduardo; Postolache, Octavian; Girão, Pedro

    2010-01-01

    Due to recent technological improvements, namely in the field of piezoelectric sensors, ballistocardiography – an almost forgotten physiological measurement – is now being object of a renewed scientific interest. Transcending the initial purposes of its development, ballistocardiography has revealed itself to be a useful informative signal about the cardiovascular system status, since it is a non-intrusive technique which is able to assess the body’s vibrations due to its cardiac, and respiratory physiological signatures. Apart from representing the outcome of the electrical stimulus to the myocardium – which may be obtained by electrocardiography – the ballistocardiograph has additional advantages, as it can be embedded in objects of common use, such as a bed or a chair. Moreover, it enables measurements without the presence of medical staff, factor which avoids the stress caused by medical examinations and reduces the patient’s involuntary psychophysiological responses. Given these attributes, and the crescent number of systems developed in recent years, it is therefore pertinent to revise all the information available on the ballistocardiogram’s physiological interpretation, its typical waveform information, its features and distortions, as well as the state of the art in device implementations. PMID:21673836

  16. Effects of Tetrodotoxin on the Mammalian Cardiovascular System

    PubMed Central

    Zimmer, Thomas

    2010-01-01

    The human genome encodes nine functional voltage-gated Na+ channels. Three of them, namely Nav1.5, Nav1.8, and Nav1.9, are resistant to nanomolar concentrations of tetrodotoxin (TTX; IC50 ? 1 ?M). The other isoforms, which are predominantly expressed in the skeletal muscle and nervous system, are highly sensitive to TTX (IC50 ~ 10 nM). During the last two decades, it has become evident that in addition to the major cardiac isoform Nav1.5, several of those TTX sensitive isoforms are expressed in the mammalian heart. Whereas immunohistochemical and electrophysiological methods demonstrated functional expression in various heart regions, the physiological importance of those isoforms for cardiac excitation in higher mammals is still debated. This review summarizes our knowledge on the systemic cardiovascular effects of TTX in animals and humans, with a special focus on cardiac excitation and performance at lower concentrations of this marine drug. Altogether, these data strongly suggest that TTX sensitive Na+ channels, detected more recently in various heart tissues, are not involved in excitation phenomena in the healthy adult heart of higher mammals. PMID:20411124

  17. The Utility of Animal Models in Understanding Links between Psychosocial Processes and Cardiovascular Health

    PubMed Central

    Grippo, Angela J.

    2011-01-01

    A bidirectional association between mood disorders and cardiovascular disease has been described; however, the neurobiological mechanisms that underlie this link have not been fully elucidated. The purpose of this review is first to describe some of the important behavioral neurobiological processes that are common to both mood and cardiovascular disorders. Second, this review focuses on the value of conducting research with animal models (primarily rodents) to investigate potential behavioral, physiological, and neural processes involved in the association of mood disorders and cardiovascular disease. In combination with findings from human research, the study of mechanisms underlying mood and cardiovascular regulation using animal models will enhance our understanding of the association of depression and cardiovascular disease, and can promote the development of novel interventions for individuals with these comorbid conditions. PMID:21949540

  18. The Sympathetic Nervous System and the Renin–Angiotensin–Aldosterone System in Cardiovascular Disease

    Microsoft Academic Search

    Robert J. Cody

    1997-01-01

    Both the sympathetic nervous system and the renin–angiotensin–aldosterone system (RAAS) have central roles in vascular adaptive processes. Stimulation of the 2 systems has been demonstrated in a range of cardiovascular disorders, including congestive heart failure and hypertension. However, elucidation regarding the interactions of the many factors involved in these 2 systems is lacking. Angiotensin-converting enzyme inhibitors have been used to

  19. Effect of sildenafil citrate on the cardiovascular system.

    PubMed

    Shinlapawittayatorn, K; Chattipakorn, S; Chattipakorn, N

    2005-09-01

    Sildenafil citrate is a drug commonly used to manage erectile dysfunction. It is designated chemically as 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H -pyrazolo[4,3-d]pyrimidin-5-yl)-4 ethoxyphenyl] sulfonyl]-4-methylpiperazine citrate (C22H30N6(O4)S). It is a highly selective inhibitor of cyclic guanine monophosphate-specific phosphodiesterase type 5. In late March through mid-November 1998, the US Food and Drug Administration (FDA) published a report on 130 confirmed deaths among men (mean age, 64 years) who received prescriptions for sildenafil citrate, a period during which >6 million outpatient prescriptions (representing about 50 million tablets) were dispensed. The US FDA recently reported that significant cardiovascular events, including sudden cardiac death, have occurred in men with erectile dysfunction who were taking sildenafil citrate. These reports have raised concerns that sildenafil citrate may increase the risk of cardiovascular events, particularly fatal arrhythmias, in patients with cardiovascular disease. In the past few years, the cardiac electrophysiological effects of sildenafil citrate have been investigated extensively in both animal and clinical studies. According to extensive data available to date, sildenafil citrate has been shown to pose minimal cardiovascular risks to healthy people taking this drug. Some precautions are needed for patients with cardiovascular diseases. However, the only absolute contraindication for sildenafil citrate is the concurrent use of nitrates. This article is intended to review sildenafil citrate's cardiovascular effects, as well as current debates about its arrhythmogenic effects. PMID:16138212

  20. Vasopressin and oxytocin in control of the cardiovascular system.

    PubMed

    Japundži?-Žigon, Nina

    2013-03-01

    Vasopressin (VP) and oxytocin (OT) are mainly synthesized in the magnocellular neurons of the paraventricular (PVN) and supraoptic nucleus (SON) of the hypothalamus. Axons from the magnocellular part of the PVN and SON project to neurohypophysis where VP and OT are released in blood to act like hormones. Axons from the parvocellular part of PVN project to extra-hypothalamic brain areas (median eminence, limbic system, brainstem and spinal cord) where VP and OT act like neurotransmitters/modulators. VP and OT act in complementary manner in cardiovascular control, both as hormones and neurotransmitters. While VP conserves water and increases circulating blood volume, OT eliminates sodium. Hyperactivity of VP neurons and quiescence of OT neurons in PVN underlie osmotic adjustment to pregnancy. In most vascular beds VP is a potent vasoconstrictor, more potent than OT, except in the umbilical artery at term. The vasoconstriction by VP and OT is mediated via V1aR. In some vascular beds, i.e. the lungs and the brain, VP and OT produce NO dependent vasodilatation. Peripherally, VP has been found to enhance the sensitivity of the baro-receptor while centrally, VP and OT increase sympathetic outflow, suppresse baro-receptor reflex and enhance respiration. Whilst VP is an important mediator of stress that triggers ACTH release, OT exhibits anti-stress properties. Moreover, VP has been found to contribute considerably to progression of hypertension and heart failure while OT has been found to decrease blood pressure and promote cardiac healing. PMID:23997756

  1. Biochemistry, Physiology and Pathophysiology of NADPH Oxidases in the Cardiovascular System

    PubMed Central

    Lassègue, Bernard; San Martín, Alejandra; Griendling, Kathy K.

    2012-01-01

    The NADPH oxidase (Nox) enzymes are critical mediators of cardiovascular physiology and pathophysiology. These proteins are expressed in virtually all cardiovascular cells, and regulate such diverse functions as differentiation, proliferation, apoptosis, senescence, inflammatory responses and oxygen sensing. They target a number of important signaling molecules, including kinases, phosphatases, transcription factors, ion channels and proteins that regulate the cytoskeleton. Nox enzymes have been implicated in many different cardiovascular pathologies: atherosclerosis, hypertension, cardiac hypertrophy and remodeling, angiogenesis and collateral formation, stroke and heart failure. In this review, we discuss in detail the biochemistry of Nox enzymes expressed in the cardiovascular system (Nox1, 2, 4 and 5), their roles in cardiovascular cell biology, and their contributions to disease development. PMID:22581922

  2. The impact of the circadian timing system on cardiovascular and metabolic function

    PubMed Central

    Morris, Christopher J.; Yang, Jessica N.; Scheer, Frank A. J. L.

    2013-01-01

    Epidemiological studies show that adverse cardiovascular events peak in the morning (i.e., between 6 AM and noon) and that shift work is associated with cardiovascular disease, obesity, and diabetes. The endogenous circadian timing system modulates certain cardiovascular risk markers to be highest (e.g., cortisol, nonlinear dynamic heart rate control, and platelet activation) or to respond most unfavorably to stressors such as exercise (e.g., epinephrine, norepinephrine, and vagal cardiac modulation) at an internal body time corresponding to the time of day when adverse cardiovascular events most likely occur. This indicates that the circadian timing system and its interaction with external cardiovascular stressors (e.g., physical activity) could contribute to the morning peak in adverse cardiovascular events. Moreover, circadian misalignment and simulated night work have adverse effects on cardiovascular and metabolic function. This suggests that misalignment between the behavioral cycle and the circadian timing system in shift workers contributes to that population’s increased risk for cardiometabolic disease. PMID:22877674

  3. Thioredoxin in the Cardiovascular System—Towards a Thioredoxin-Based Antioxidative Therapy

    Microsoft Academic Search

    Bradford C. Berk

    \\u000a Oxidative stress results from an imbalance between the production of reactive oxygen species (ROS) and the endogenous antioxidant\\u000a systems, which detoxify the reactive intermediates. Diseases of the cardiovascular system, including atherosclerosis, diabetes,\\u000a cardiac hypertrophy, and congestive heart disease are characterized by enhanced production of ROS. In these conditions ROS\\u000a promote cardiovascular pathology in part by activating inflammatory signaling pathways. One

  4. Designing an outcome-oriented computer decision-support system for cardiovascular ICU—A preliminary report

    Microsoft Academic Search

    Francis Lau; Daniel Vincent; Don Fenna; Randy Goebel; Dennis Modry

    1991-01-01

    This paper describes the conceptual framework and preliminary results of an outcome-oriented decision-support system prototype for the cardiovascular intensive care unit (CVICU). The major characteristics of this design include: (1) its problem-based approach to solving clinical problems; (2) an integrated structure with the hospital information system in terms of its data, model and knowledge bases; (3) proposed alternative modes of

  5. Computer systems analysis of the cardiovascular mechanisms of reentry orthostasis in astronauts.

    PubMed

    Summers, R L; Coleman, T G

    2002-01-01

    Reentry orthostasis secondary to a prolonged exposure to microgravity is a common problem among astronauts. However, the physiologic mechanisms are poorly understood due to the many control systems involved. In this study an advanced computer model of cardiovascular functioning was employed in a systems analysis approach to clarify the relative importance of some of the adaptive physiologic processes engaged when humans return from space. After simulation of the conditions of zero gravity for one month, the model predicted that the change in capacitance of the lower extremity veins resulting from a loss of external fluid forces in the dehydrated extracellular compartment was the dominant mechanism associated with reentry orthostasis. This condition appears accentuated in women due to their inherent lower center of gravity and proportionately larger mass in the lower extremities. PMID:14686452

  6. Modeling Cardiovascular Anatomy from Patient-Specific Imaging

    NASA Astrophysics Data System (ADS)

    Bajaj, Chandrajit; Goswami, Samrat

    The importance of modern imaging techniques for capturing detailed structural information of a biological system cannot be understated. Unfortunately images do not reveal the "full functional story" and a spatially realistic computer model is often necessary for a comprehensive understanding of the complicated structural and physiological properties of the biological system's entities under investigation [1]. Deeper insights into structure-to-function relationships of different entities is achieved via finite element simulations of the modeled biomedical process. A 3D (three dimensional) finite element meshed computer model of the biological system is therefore a first step to perform such simulations.

  7. The effects of metabolic diseases on the cardiovascular system.

    PubMed

    Gilbert, E F

    1987-01-01

    Many metabolic diseases result in pathological changes within the cardiovascular system, often with the most severe effects on the function of the heart and great vessels. Metabolic disorders affecting the heart include disorders of amino acid metabolism, storage diseases, neuromuscular diseases, diseases of metal and pigment metabolism, carnitine deficiency, and connective tissue disorders. Several inborn errors of metabolism may involve the myocardium due to the accumulation of abnormal metabolites in the myocardial cells. In addition, the heart valves and coronary vessels may be involved. If the predominant effect is in the myocardial cell, it will be manifested clinically as a cardiomyopathy. Some disorders, in particular oxalosis, may involve the conduction system as a result of the deposition of oxalate crystals and result in conduction disturbances such as in alkaptonuria, primary oxalosis, and homocystinuria. Myocardial involvement may result in cardiomyopathy of the three functional types: (1) congestive, as in Fabry's disease, (2) hypertrophic, as in glycogen storage disease, type II, or (3) restrictive, as in Gaucher's disease. In the storage disease severe valvular as well as myocardial involvement occur predominantly in the glycogen storage diseases, types II-IV, mucolipidoses, sphingolipidoses, and neuronal ceroid lipofuscinosis. There are a variety of neuromuscular disorders that may be associated with cardiomyopathy, including the muscular dystrophies, Friedreich's ataxia, and Kugelberg-Welander syndrome. The pathological features of these conditions are not specific, but result usually in a congestive form of cardiomyopathy. Patients with metal and pigment metabolic disorders include iron storage disease, either hemochromatosis or transfusional hemosiderosis, Menkes' kinky hair syndrome, and Dubin-Johnson syndrome. Either a restrictive or a congestive form of cardiomyopathy may occur. The systemic form of carnitine deficiency is an autosomal recessive disorder and may present as a cardiomyopathy with congestive heart failure and lipid accumulation in the myocardial cells. Connective tissue disorders are generalized diseases that may involve the heart and valvular tissue, but also the blood vessels. These include Marfan's syndrome, Ehlers-Danlos syndrome, osteogenesis imperfecta, and pseudo-xanthoma elasticum. PMID:3333140

  8. [Adverse effects of ultrafine particles on the cardiovascular system and its mechanisms].

    PubMed

    Yi, Tie-ci; Li, Jian-ping

    2014-12-18

    Cardiovascular disease is one of the major threats to human. Air pollution, which , as it become a problem too serious to be ignored in China, is known to be an important risk factor for cardiovascular disease. Among all pollutants, ultrafine particles ( UFPs) , defined as particles with their diameter less than 0. 1 f.Lm, are a specific composition. They are very small in size, large in quantity and surface area, and most important, capable of passing through the air-blood barrier. These unique features of UFPs make them special in their impact on cardiovascular system. Nowadays, the influence of UFPs on the cardiovascular system has become a hot topic. On the one side, studies have shown that UFPs can cause inflammation and oxidative stress in the lung, and then induce systemic inflammation by releasing cytokine and reactive oxygen species into the circulation. On the other side, UFPs themselves can "spillout"into the circulation and interact with their targets. By this way, UFPs directly affect endothelial cells, myocardial cells and the autonomic nervous system, which ultimately result in increased cardiovascular events. We intend to make an overview about the recent progress about the influence of UFPs on human cardiovascular disease and the related mechanisms, and argue for more attention to this issue. PMID:25651605

  9. Circadian Rhythm in the Cardiovascular System: Considerations in Non-Invasive Electrophysiology

    Microsoft Academic Search

    Yi-Fang Guo; Phyllis K. Stein

    2002-01-01

    Most cardiovascular activities show a circadian rhythm, as do electrophysiological phenomenon. Under theinfluence of both external stimuli and endogenous homoeostatic mechanisms, cardiac electrophysiologicalproperties change diurnally and enable the cardiovascular system adapt to rest-exercise cycles. According torecent reports, almost all non-invasive electrophysiological phenomena, such as electrocardiographic indices,cardiac refractoriness and conduction, pacing and defibrillation threshold, heart rate variability indices, andeven Q-T dispersion

  10. Statistical Modelling of Cardiovascular Data. An Introduction to Linear Mixed Models

    Microsoft Academic Search

    Paulo Goncalves; Christophe Lenoir; Christophe Heymes; Bernard Swynghedauw; Christian Lavergne

    Abstract: Most of statistical approaches,in cardiovascular research were based on variance analysis (ANOVA). However, most of the time, the assumption that data are independent,is violated since several measures,are performed,on the same,subject (repeated measures). In addition, the presence of intra- and inter-observers variability can potentially obscure significant differences. The linear mixed model (LMM) is an extended multivariate linear regression method of

  11. Cardiovascular physiology in space flight

    NASA Technical Reports Server (NTRS)

    Charles, John B.; Bungo, Michael W.

    1991-01-01

    The effects of space flight on the cardiovascular system have been studied since the first manned flights. In several instances, the results from these investigations have directly contradicted the predictions based on established models. Results suggest associations between space flight's effects on other organ systems and those on the cardiovascular system. Such findings provide new insights into normal human physiology. They must also be considered when planning for the safety and efficiency of space flight crewmembers.

  12. Cardiovascular consequences of loss of supraspinal control of the sympathetic nervous system after spinal cord injury

    Microsoft Academic Search

    Robert W. Teasell; J. Malcolm O. Arnold; Andrei Krassioukov; Gail A. Delaney

    2000-01-01

    Teasell RW, Arnold JMO, Krassioukov A, Delaney GA. Cardiovascular consequences of loss of supraspinal control of the sympathetic nervous system after spinal cord injury. Arch Phys Med Rehabil 2000;81:506-16. Spinal cord injury (SCI) with resultant quadriplegia or high paraplegia is associated with significant dysfunction of the sympathetic nervous system. This alteration of sympathetic nervous system activity occurs as a consequence

  13. Imbalance between endothelial damage and repair: a gateway to cardiovascular disease in systemic lupus erythematosus.

    PubMed

    Mak, Anselm; Kow, Nien Yee

    2014-01-01

    Atherosclerosis is accelerated in patients with systemic lupus erythematosus (SLE) and it leads to excessive cardiovascular complications in these patients. Despite the improved awareness of cardiovascular disease and advent of clinical diagnostics, the process of atherogenesis in most patients remains clinically silent until symptoms and signs of cardiovascular complications develop. As evidence has demonstrated that vascular damage is already occurring before clinically overt cardiovascular disease develops in lupus patients, intervention at the preclinical stage of atherogenesis would be plausible. Indeed, endothelial dysfunction, one of the earliest steps of atherogenesis, has been demonstrated to occur in lupus patients even when they are naïve for cardiovascular disease. Currently known "endothelium-toxic" factors including type 1 interferon, proinflammatory cytokines, inflammatory cells, immune complexes, costimulatory molecules, neutrophils extracellular traps, lupus-related autoantibodies, oxidative stress, and dyslipidemia, coupled with the aberrant functions of the endothelial progenitor cells (EPC) which are crucial to vascular repair, likely tip the balance towards endothelial dysfunction and propensity to develop cardiovascular disease in lupus patients. In this review, altered physiology of the endothelium, factors leading to perturbed vascular repair contributed by lupus EPC and the impact of proatherogenic factors on the endothelium which potentially lead to atherosclerosis in lupus patients will be discussed. PMID:24790989

  14. Imbalance between Endothelial Damage and Repair: A Gateway to Cardiovascular Disease in Systemic Lupus Erythematosus

    PubMed Central

    2014-01-01

    Atherosclerosis is accelerated in patients with systemic lupus erythematosus (SLE) and it leads to excessive cardiovascular complications in these patients. Despite the improved awareness of cardiovascular disease and advent of clinical diagnostics, the process of atherogenesis in most patients remains clinically silent until symptoms and signs of cardiovascular complications develop. As evidence has demonstrated that vascular damage is already occurring before clinically overt cardiovascular disease develops in lupus patients, intervention at the preclinical stage of atherogenesis would be plausible. Indeed, endothelial dysfunction, one of the earliest steps of atherogenesis, has been demonstrated to occur in lupus patients even when they are naïve for cardiovascular disease. Currently known “endothelium-toxic” factors including type 1 interferon, proinflammatory cytokines, inflammatory cells, immune complexes, costimulatory molecules, neutrophils extracellular traps, lupus-related autoantibodies, oxidative stress, and dyslipidemia, coupled with the aberrant functions of the endothelial progenitor cells (EPC) which are crucial to vascular repair, likely tip the balance towards endothelial dysfunction and propensity to develop cardiovascular disease in lupus patients. In this review, altered physiology of the endothelium, factors leading to perturbed vascular repair contributed by lupus EPC and the impact of proatherogenic factors on the endothelium which potentially lead to atherosclerosis in lupus patients will be discussed. PMID:24790989

  15. Regulators and effectors of bone morphogenetic protein signalling in the cardiovascular system.

    PubMed

    Luo, Jiang-Yun; Zhang, Yang; Wang, Li; Huang, Yu

    2015-07-15

    Bone morphogenetic proteins (BMPs) play key roles in the regulation of cell proliferation, differentiation and apoptosis in various tissues and organs, including the cardiovascular system. BMPs signal through both Smad-dependent and -independent cascades to exert a wide spectrum of biological activities. Cardiovascular disorders such as abnormal angiogenesis, atherosclerosis, pulmonary hypertension and cardiac hypertrophy have been linked to aberrant BMP signalling. To correct the dysregulated BMP signalling in cardiovascular pathogenesis, it is essential to get a better understanding of how the regulators and effectors of BMP signalling control cardiovascular function and how the dysregulated BMP signalling contributes to cardiovascular dysfunction. We hence highlight several key regulators of BMP signalling such as extracellular regulators of ligands, mechanical forces, microRNAs and small molecule drugs as well as typical BMP effectors like direct downstream target genes, mitogen-activated protein kinases, reactive oxygen species and microRNAs. The insights into these molecular processes will help target both the regulators and important effectors to reverse BMP-associated cardiovascular pathogenesis. PMID:25952563

  16. The effects of exercise on blood flow with reference to the human cardiovascular system: a finite element study

    NASA Technical Reports Server (NTRS)

    Sud, V. K.; Srinivasan, R. S.; Charles, J. B.; Bungo, M. W.

    1992-01-01

    This paper reports on a theoretical investigation into the effects of vasomotion on blood through the human cardiovascular system. The finite element method has been used to analyse the model. Vasoconstriction and vasodilation may be effected either through the action of the central nervous system or autoregulation. One of the conditions responsible for vasomotion is exercise. The proposed model has been solved and quantitative results of flows and pressures due to changing the conductances of specific networks of arterioles, capillaries and venules comprising the arms, legs, stomach and their combinations have been obtained.

  17. Exploratory and developmental studies leading toward optimization of acoustical holography imaging of cardiovascular system, volume 2

    Microsoft Academic Search

    B. B. Brenden; J. L. Deichman

    1975-01-01

    The objectives of the second phase of this program were to better the imaging capability of the liquid surface acoustical holography system as it relates to the cardiovascular system, to continue the safety study involved with insonification of fertilized fish eggs and to explore the feasibility of using electron spin resonance (ESR) to detect tissue damage from ultrasonic insonification. Lens

  18. Implementation of a computerized cardiovascular information system in a private hospital setting

    Microsoft Academic Search

    Gregory S. Taylor; Joseph B. Muhlestein; Galen S. Wagner; Tami L. Bair; Patty Li; Jeffrey L. Anderson

    1998-01-01

    Background The use of clinical databases improves quality of care, reduces operating costs, helps secure managed care contracts, and assists in clinical research. Because of the large physician input required to maintain these systems, private institutions have often found them difficult to implement. At LDS Hospital in Salt Lake City, Utah, we developed a cardiovascular information system (LDS-CIS) patterned after

  19. Effectiveness and cost effectiveness of cardiovascular disease prevention in whole populations: modelling study

    PubMed Central

    2011-01-01

    Objective To estimate the potential cost effectiveness of a population-wide risk factor reduction programme aimed at preventing cardiovascular disease. Design Economic modelling analysis. Setting England and Wales. Population Entire population. Model Spreadsheet model to quantify the reduction in cardiovascular disease over a decade, assuming the benefits apply consistently for men and women across age and risk groups. Main outcome measures Cardiovascular events avoided, quality adjusted life years gained, and savings in healthcare costs for a given effectiveness; estimates of how much it would be worth spending to achieve a specific outcome. Results A programme across the entire population of England and Wales (about 50 million people) that reduced cardiovascular events by just 1% would result in savings to the health service worth at least £30m (€34m; $48m) a year compared with no additional intervention. Reducing mean cholesterol concentrations or blood pressure levels in the population by 5% (as already achieved by similar interventions in some other countries) would result in annual savings worth at least £80m to £100m. Legislation or other measures to reduce dietary salt intake by 3 g/day (current mean intake approximately 8.5 g/day) would prevent approximately 30?000 cardiovascular events, with savings worth at least £40m a year. Legislation to reduce intake of industrial trans fatty acid by approximately 0.5% of total energy content might gain around 570?000 life years and generate NHS savings worth at least £230m a year. Conclusions Any intervention that achieved even a modest population-wide reduction in any major cardiovascular risk factor would produce a net cost saving to the NHS, as well as improving health. Given the conservative assumptions used in this model, the true benefits would probably be greater. PMID:21798967

  20. A Follow-Up Study of Medical Students' Biomedical Understanding and Clinical Reasoning Concerning the Cardiovascular System

    ERIC Educational Resources Information Center

    Ahopelto, Ilona; Mikkila-Erdmann, Mirjamaija; Olkinuora, Erkki; Kaapa, Pekka

    2011-01-01

    Novice medical students usually hold initial conceptions concerning medical domains, such as the cardiovascular system, which may contradict scientific explanations and thus hinder learning. The purpose of this study was to investigate which kinds of biomedical representations medical students constructed of the central cardiovascular system in…

  1. Depressive and cardiovascular disease comorbidity in a rat model of social stress: a putative role for corticotropin-releasing factor

    PubMed Central

    McFadden, Kile V.; Grigoriadis, Dimitri; Bhatnagar, Seema; Valentino, Rita J.

    2013-01-01

    Rationale Depression is associated with medical comorbidities, particularly cardiovascular disease. However, mechanisms linking depression and cardiovascular disease remain unclear. Objectives This study investigated whether the rat resident–intruder model of social stress would elicit behavioral dysfunctions and autonomic changes characteristic of psychiatric/cardiovascular comorbidity. Furthermore, the efficacy of the corticotropin-releasing factor-1 (CRF1) receptor antagonist, NBI-30775 (NBI), or the tricyclic antidepressant, desipramine (DMI), to prevent social stress-induced behavioral, neuroendocrine, and cardiovascular changes were evaluated. Methods Adult male rats were exposed to resident–intruder stress (seven consecutive days) and systemically administered NBI (10 mg/kg/7 days), DMI (10 mg/kg/14 days), or vehicle. The efficacy of NBI and DMI to alter the behavioral and neuroendocrine responses to social stress was assessed. Furthermore, their effects on stress-induced forced swim behavior (FST), bladder and adrenal weight, and heart rate variability (HRV) were examined. Results NBI, but not DMI, increased time spent in an upright, defensive posture and the latency to submit to the resident. Additionally, only NBI reduced social stress-induced adrenocorticotropic hormone and corticosterone release. Social stress increased FST immobility, caused bladder and adrenal hypertrophy, and decreased HRV. Both NBI and DMI blocked stress-induced increases in immobility during the FST. However, only NBI inhibited social stress-induced adrenal and bladder hypertrophy and decreases in heart rate variability. Conclusions Rat resident–intruder stress paradigm models aspects of psychiatric/medical comorbidity. Furthermore, the CRF system may contribute to both the behavioral response during social stress and its behavioral and autonomic consequences, offering insight into potential therapy to treat these comorbid conditions. PMID:22322324

  2. Role Models and the Psychological Characteristics That Buffer Low-Socioeconomic-Status Youth from Cardiovascular Risk

    ERIC Educational Resources Information Center

    Chen, Edith; Lee, William K.; Cavey, Lisa; Ho, Amanda

    2013-01-01

    Little is understood about why some youth from low-socioeconomic-status (SES) environments exhibit good health despite adversity. This study tested whether role models and "shift-and-persist" approaches (reframing stressors more benignly while persisting with future optimism) protect low-SES youth from cardiovascular risk. A total of 163…

  3. TEMPORAL ASSOCIATION BETWEEN PULMONARY AND SYSTEMIC EFFECTS OF PARTICULATE MATTER IN HEALTHY AND CARDIOVASCULAR COMPROMISED RATS

    EPA Science Inventory

    Temporal association between pulmonary and systemic effects of particulate matter in healthy and cardiovascular compromised ratsUrmila P. Kodavanti, Mette C. Schladweiler, Allen D. Ledbetter, Russ Hauser*, David C. Christiani*, John McGee, Judy R. Richards, Daniel L. Co...

  4. Dexmedetomidine Modulates Cardiovascular Responses to Stimulation of Central Nervous System Pressor Sites

    Microsoft Academic Search

    Neil E. Farber; Enric Samso; Michael Staunton; David Schwabe; William T. Schmeling

    1999-01-01

    Halothane attenuates the alterations in arterial pressure (BP) and heart rate (HR) produced by central nervous system (CNS) stimulation. We examined the effects of the a2-adrenergic agonist dexmedetomidine, with and without halothane, on cardiovascular regulation dur- ing CNS pressor site stimulation in chronically instru- mented cats. Stimuli trains via bipolar stimulating elec- trodes in the hypothalamus and reticular formation elicited

  5. Electrode structures for acquisition and neural stimulation controlling the cardiovascular system.

    PubMed

    Steltenkamp, Siegfried; Becher, Kai; Doerge, Thomas; Ruff, Roman; Hoffmann, Klaus-Peter

    2009-01-01

    In this study we present an innovative electrode system, for many different applications in the field of cardiovascular diseases. It is a combination of intelligent communicating dry-surface electrodes, which are able to interact with different sensors especially with an invasive, ultra flexible electrode-system. Dry and smart surface electrodes, which can be integrated in textiles and therefore such electrode are almost "invisible" for patients, are used for ECG acquisition and can be integrated in a communication network. In combination with a pulse oximeter or impedance spectroscopy the pulse transit time (PTT) can be calculated. Additionally, with invasive electrodes the nervous vagus can be stimulated and therefore cardiovascular functions can be controlled. The association of an implanted stimulator with an interacting and smart monitoring system results into a cardiovascular controlling. In this work we will focus on the feasibility, suitability, fabrication and characterization of invasive and dry-surface electrode systems as a basic element and foundation for cardiovascular regulation in a closed loop. PMID:19965045

  6. Hydrogen Peroxide Sensing and Signaling by Protein Kinases in the Cardiovascular System

    PubMed Central

    Burgoyne, Joseph R.; Oka, Shin-ichi; Ale-Agha, Niloofar

    2013-01-01

    Abstract Significance: Oxidants were once principally considered perpetrators of injury and disease. However, this has become an antiquated view, with cumulative evidence showing that the oxidant hydrogen peroxide serves as a signaling molecule. Hydrogen peroxide carries vital information about the redox state of the cell and is crucial for homeostatic regulation during health and adaptation to stress. Recent Advances: In this review, we examine the contemporary concepts for how hydrogen peroxide is sensed and transduced into a biological response by introducing post-translational oxidative modifications on select proteins. Oxidant sensing and signaling by kinases are of particular importance as they integrate oxidant signals into phospho-regulated pathways. We focus on CAMKII, PKA, and PKG, kinases whose redox regulation has notable impact on cardiovascular function. Critical Issues: In addition, we examine the mechanism for regulating intracellular hydrogen peroxide, considering the net concentrations that may accumulate. The effects of endogenously generated oxidants are often modeled by applying exogenous hydrogen peroxide to cells or tissues. Here we consider whether model systems exposed to exogenous hydrogen peroxide have relevance to systems where the oxidant is generated endogenously, and if so, what concentration can be justified in terms of relevance to health and disease. Future Directions: Improving our understanding of hydrogen peroxide signaling and the sensor proteins that it can modify will help us develop new strategies to regulate intracellular signaling to prevent disease. Antioxid. Redox Signal. 18, 1042–1052. PMID:22867279

  7. System identification of closed-loop cardiovascular control: effects of posture and autonomic blockade

    NASA Technical Reports Server (NTRS)

    Mullen, T. J.; Appel, M. L.; Mukkamala, R.; Mathias, J. M.; Cohen, R. J.

    1997-01-01

    We applied system identification to the analysis of fluctuations in heart rate (HR), arterial blood pressure (ABP), and instantaneous lung volume (ILV) to characterize quantitatively the physiological mechanisms responsible for the couplings between these variables. We characterized two autonomically mediated coupling mechanisms [the heart rate baroreflex (HR baroreflex) and respiratory sinus arrhythmia (ILV-HR)] and two mechanically mediated coupling mechanisms [the blood pressure wavelet generated with each cardiac contraction (circulatory mechanics) and the direct mechanical effects of respiration on blood pressure (ILV-->ABP)]. We evaluated the method in humans studied in the supine and standing postures under control conditions and under conditions of beta-sympathetic and parasympathetic pharmacological blockades. Combined beta-sympathetic and parasympathetic blockade abolished the autonomically mediated couplings while preserving the mechanically mediated coupling. Selective autonomic blockade and postural changes also altered the couplings in a manner consistent with known physiological mechanisms. System identification is an "inverse-modeling" technique that provides a means for creating a closed-loop model of cardiovascular regulation for an individual subject without altering the underlying physiological control mechanisms.

  8. Influence of mitochondrion-toxic agents on the cardiovascular system.

    PubMed

    Finsterer, Josef; Ohnsorge, Peter

    2013-12-01

    Cardiovascular disease may be induced or worsened by mitochondrion-toxic agents. Mitochondrion-toxic agents may be classified as those with or without a clinical effect, those which induce cardiac disease only in humans or animals or both, as prescribed drugs, illicit drugs, exotoxins, or nutritiants, as those which affect the heart exclusively or also other organs, as those which are effective only in patients with a mitochondrial disorder or cardiac disease or also in healthy subjects, or as solid, liquid, or volatile agents. In humans, cardiotoxic agents due to mitochondrial dysfunction include anthracyclines (particularly doxorubicin), mitoxantrone, cyclophosphamide, cisplatin, fluorouracil, imatinib, bortezomib, trastuzumab, arsenic trioxide, cyclosporine-A, zidovudine, lamotrigine, glycosides, lidocain, isoproterenol, nitroprusside, pivalic acid, alcohol, cocaine, pesticides, cadmium, mycotoxins, cyanotoxins, meat meal, or carbon monoxide. Even more agents exhibit cardiac abnormalities due to mitochondrion-toxicity only in animals or tissue cultures. The mitochondrion-toxic effect results from impairment of the respiratory chain, the oxidative phosphorylation, the Krebs cycle, or the ?-oxidation, from decrease of the mitochondrion-membrane potential, from increased oxidative stress, reduced anti-oxidative capacity, or from induction of apoptosis. Cardiac abnormalities induced via these mechanisms include cardiomyopathy, myocarditis, coronary heart disease, arrhythmias, heart failure, or Takotsubo syndrome. Discontinuation of the cardiotoxic agent results in complete recovery in the majority of the cases. Antioxidants and nutritiants may be of additional help. Particularly coenzyme-Q, riboflavin, vitamin-E, vitamin-C, L-carnitine, vitamin-D, thiamin, folic acid, omega-3 fatty acids, and D-ribose may alleviate mitochondrial cardiotoxic effects. PMID:24036395

  9. Adenosinergic regulation of the cardiovascular system in the red-eared slider Trachemys scripta.

    PubMed

    Joyce, William; Wang, Tobias

    2014-08-01

    Few studies have investigated adenosinergic regulation of the cardiovascular system in reptiles. The haemodynamic effect of a bolus intra-arterial adenosine injection (2.5 ?M kg?¹) was investigated in nine anaesthetised red-eared sliders (Trachemys scripta). Adenosine caused a transient bradycardia, which was accompanied by systemic vasodilatation as evidenced by an increase in systemic flow and a decrease in systemic pressure. Meanwhile, pulmonary flow fell significantly. Both the bradycardia and increase in systemic conductance were significantly attenuated by theophylline (4 mg kg?¹), demonstrating an involvement of P? receptors. These results suggest that adenosine is likely to play a significant role in reptile cardiovascular physiology. In turtles specifically, adenosinergic regulation may be particularly relevant during periods of apnoea. PMID:24726607

  10. 25-Hydroxyvitamin D and Cardiovascular Risk Factors in Women with Systemic Lupus Erythematosus

    PubMed Central

    Wu, Peggy W.; Rhew, Elisa Y.; Dyer, Alan R.; Dunlop, Dorothy D.; Langman, Craig B.; Price, Heather; Sutton-Tyrrell, Kim; McPherson, David D.; Edmundowicz, Daniel; Kondos, George T.; Ramsey-Goldman, Rosalind

    2009-01-01

    Objective Low serum levels of 25-hydroxyvitamin D (25[OH]D, vitamin D) are associated with a higher frequency of cardiovascular disease and risk factors in the general population. Vitamin D deficiency has been noted in systemic lupus erythematosus (SLE). The objective of this study was to evaluate the associations of serum 25(OH)D levels with cardiovascular risk factors in women with SLE. Methods Data collected in 181 women with SLE included demographics, SLE activity and damage assessments, cardiovascular risk factors, medications, and laboratory assessments of inflammatory markers and 25(OH)D levels. Multiple linear and logistic regressions were used to estimate the association of 25(OH)D with cardiovascular risk factors. Results Mean age and disease duration were 43.2 and 11.9 years, respectively. Mean 25(OH)D was 27.1 ng/ml and 62.2% had 25(OH)D levels <30 ng/ml. In unadjusted analyses, lower 25(OH)D levels were significantly associated with higher diastolic blood pressure, low density lipoprotein cholesterol (LDL-c), lipoprotein (a), body mass index (BMI), and fibrinogen levels, as well as self-reported hypertension and diabetes. Lower 25(OH)D levels were also significantly associated with higher SLE disease activity and damage scores. After adjustment for age, seasonal variation, and race/ethnicity, lower 25(OH)D levels were also significantly related to higher fasting serum glucose. With further adjustment for BMI, associations between 25(OH)D and cardiovascular risk factors were no longer significant. Conclusion This study demonstrates that vitamin D levels are low in women with SLE and significant associations exist with selected cardiovascular risk factors although most of these associations can be explained by BMI. PMID:19790113

  11. Experimental Models of Oxidative Stress Related to Cardiovascular Diseases and Diabetes

    Microsoft Academic Search

    Maria D. Mesa; Concepcion M. Aguilera; Angel Gil

    \\u000a In this chapter we summarize the commonly used animal models employed in the study of cardiovascular diseases and diabetes,\\u000a two of the most prevalent oxidative stress-induced diseases. A number of animal models of atherosclerosis support the notion\\u000a that reactive oxygen and nitrogen species have a causal role in atherosclerosis and other vascular diseases. Experimental\\u000a atherosclerosis is induced by specific lipid-rich

  12. Cardiovascular and other dynamic systems in long-term space flight

    NASA Technical Reports Server (NTRS)

    Tipton, David A.

    1987-01-01

    The paper examines the physiology of the cardiovascular system, and to a lesser extent the endocrine, renal, and hematopoietic systems. The paper highlights the aspects of these areas that are most pertinent to space manufacturing, i.e., working in space. Areas covered include the physiological costs of working in microgravity and partial gravity (e.g., the moon or Mars), countermeasures to potentially adverse physiological adaptations, and problems associated with return to earth after long periods of weightlessness.

  13. The Applicability of Nonlinear Systems Dynamics Chaos Measures to Cardiovascular Physiology Variables

    NASA Technical Reports Server (NTRS)

    Hooker, John C.

    1991-01-01

    Three measures of nonlinear chaos (fractal dimension, Approximate Entropy (ApEn), and Lyapunov exponents) were studied as potential measures of cardiovascular condition. It is suggested that these measures have potential in the assessment of cardiovascular condition in environments of normal cardiovascular stress (normal gravity on the Earth surface), cardiovascular deconditioning (microgravity of space), and increased cardiovascular stress (lower body negative pressure (LBNP) treatments).

  14. Mathematical modeling of cardiovascular coupling: Central autonomic commands and baroreflex control.

    PubMed

    Silvani, Alessandro; Magosso, Elisa; Bastianini, Stefano; Lenzi, Pierluigi; Ursino, Mauro

    2011-07-01

    The cross-correlation function (CCF) yields the correlation coefficient between spontaneous fluctuations of heart period and blood pressure as a function of the time shift between these variables. Two CCF patterns occur in humans: I) positive correlation between heart period and previous pressure values; II) negative correlation between heart period and subsequent pressure values. These patterns may result from the baroreflex and central autonomic commands (CAC), respectively. The aim of this study was to test this interpretation with a non-linear mathematical model of the human cardiovascular system. CAC were modeled as either phasic changes or random fluctuations of vagal and sympathetic activities with opposite sign. CCF pattern I resulted from baroreflex buffering of blood pressure changes elicited by vascular resistance fluctuations. When cardiac baroreflex control was absent or outweighed by CAC to the heart, simulations resulted in CCF pattern II only. In intermediate conditions when cardiac baroreflex interacted with CAC to the heart, CCF patterns I and II coexisted because the coupling between heart period and blood pressure varied with time. CAC to the heart decreased in magnitude the correlation coefficient and lengthened the time shift of CCF pattern I, thus apparently slowing and blunting baroreflex effects. Conversely, the baroreflex decreased in magnitude the correlation coefficient of CCF pattern II, thus blunting CAC effects. These results provide theoretical evidence in favor of application of the CCF analysis to investigate the balance between central autonomic and baroreflex cardiac control. PMID:21550860

  15. Projections of preventable risks for cardiovascular disease in Canada to 2021: a microsimulation modelling approach

    PubMed Central

    Manuel, Douglas G.; Tuna, Meltem; Hennessy, Deirdre; Okhmatovskaia, Anya; Finès, Philippe; Tanuseputro, Peter; Tu, Jack V.; Flanagan, William

    2014-01-01

    Background Reductions in preventable risks associated with cardiovascular disease have contributed to a steady decrease in its incidence over the past 50 years in most developed countries. However, it is unclear whether this trend will continue. Our objective was to examine future risk by projecting trends in preventable risk factors in Canada to 2021. Methods We created a population-based microsimulation model using national data on births, deaths and migration; socioeconomic data; cardiovascular disease risk factors; and algorithms for changes in these risk factors (based on sociodemographic characteristics and previous cardiovascular disease risk). An initial population of 22.5 million people, representing the Canadian adult population in 2001, had 13 characteristics including the risk factors used in clinical risk prediction. There were 6.1 million potential exposure profiles for each person each year. Outcome measures included annual prevalence of risk factors (smoking, obesity, diabetes, hypertension and lipid levels) and of co-occurring risks. Results From 2003 to 2009, the projected risks of cardiovascular disease based on the microsimulation model closely approximated those based on national surveys. Except for obesity and diabetes, all risk factors were projected to decrease through to 2021. The largest projected decreases were for the prevalence of smoking (from 25.7% in 2001 to 17.7% in 2021) and uncontrolled hypertension (from 16.1% to 10.8%). Between 2015 and 2017, obesity was projected to surpass smoking as the most prevalent risk factor. Interpretation Risks of cardiovascular disease are projected to decrease modestly in Canada, leading to a likely continuing decline in its incidence. PMID:25077135

  16. Sinapic Acid Prevents Hypertension and Cardiovascular Remodeling in Pharmacological Model of Nitric Oxide Inhibited Rats

    PubMed Central

    Silambarasan, Thangarasu; Manivannan, Jeganathan; Krishna Priya, Mani; Suganya, Natarajan; Chatterjee, Suvro; Raja, Boobalan

    2014-01-01

    Objectives Hypertensive heart disease is a constellation of abnormalities that includes cardiac fibrosis in response to elevated blood pressure, systolic and diastolic dysfunction. The present study was undertaken to examine the effect of sinapic acid on high blood pressure and cardiovascular remodeling. Methods An experimental hypertensive animal model was induced by L-NAME intake on rats. Sinapic acid (SA) was orally administered at a dose of 10, 20 and 40 mg/kg body weight (b.w.). Blood pressure was measured by tail cuff plethysmography system. Cardiac and vascular function was evaluated by Langendorff isolated heart system and organ bath studies, respectively. Fibrotic remodeling of heart and aorta was assessed by histopathologic analyses. Oxidative stress was measured by biochemical assays. mRNA and protein expressions were assessed by RT-qPCR and western blot, respectively. In order to confirm the protective role of SA on endothelial cells through its antioxidant property, we have utilized the in vitro model of H2O2-induced oxidative stress in EA.hy926 endothelial cells. Results Rats with hypertension showed elevated blood pressure, declined myocardial performance associated with myocardial hypertrophy and fibrosis, diminished vascular response, nitric oxide (NO) metabolites level, elevated markers of oxidative stress (TBARS, LOOH), ACE activity, depleted antioxidant system (SOD, CAT, GPx, reduced GSH), aberrant expression of TGF-?, ?-MHC, eNOS mRNAs and eNOS protein. Remarkably, SA attenuated high blood pressure, myocardial, vascular dysfunction, cardiac fibrosis, oxidative stress and ACE activity. Level of NO metabolites, antioxidant system, and altered gene expression were also repaired by SA treatment. Results of in vitro study showed that, SA protects endothelial cells from oxidative stress and enhance the production of NO in a concentration dependent manner. Conclusions Taken together, these results suggest that SA may have beneficial role in the treatment of hypertensive heart disease by attenuating fibrosis and oxidative stress through its antioxidant potential. PMID:25531679

  17. A new oxidative stress model, 2,2-azobis(2-amidinopropane) dihydrochloride induces cardiovascular damages in chicken embryo.

    PubMed

    He, Rong-Rong; Li, Yan; Li, Xiao-Di; Yi, Ruo-Nan; Wang, Xiao-Yu; Tsoi, Bun; Lee, Kenneth Ka Ho; Abe, Keiichi; Yang, Xuesong; Kurihara, Hiroshi

    2013-01-01

    It is now well established that the developing embryo is very sensitive to oxidative stress, which is a contributing factor to pregnancy-related disorders. However, little is known about the effects of reactive oxygen species (ROS) on the embryonic cardiovascular system due to a lack of appropriate ROS control method in the placenta. In this study, a small molecule called 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH), a free radicals generator, was used to study the effects of oxidative stress on the cardiovascular system during chick embryo development. When nine-day-old (stage HH 35) chick embryos were treated with different concentrations of AAPH inside the air chamber, it was established that the LD50 value for AAPH was 10 µmol/egg. At this concentration, AAPH was found to significantly reduce the density of blood vessel plexus that was developed in the chorioallantoic membrane (CAM) of HH 35 chick embryos. Impacts of AAPH on younger embryos were also examined and discovered that it inhibited the development of vascular plexus on yolk sac in HH 18 embryos. AAPH also dramatically repressed the development of blood islands in HH 3+ embryos. These results implied that AAPH-induced oxidative stress could impair the whole developmental processes associated with vasculogenesis and angiogenesis. Furthermore, we observed heart enlargement in the HH 40 embryo following AAPH treatment, where the left ventricle and interventricular septum were found to be thickened in a dose-dependent manner due to myocardiac cell hypertrophy. In conclusion, oxidative stress, induced by AAPH, could lead to damage of the cardiovascular system in the developing chick embryo. The current study also provided a new developmental model, as an alternative for animal and cell models, for testing small molecules and drugs that have anti-oxidative activities. PMID:23469224

  18. Characterization of Coherent Structures in the Cardiovascular System

    PubMed Central

    Shadden, Shawn C.; Taylor, Charles A.

    2013-01-01

    Recent advances in blood flow modeling have provided highly resolved, four-dimensional data of fluid mechanics in large vessels. The motivation for such modeling is often to better understand how flow conditions relate to health and disease, or to evaluate interventions that affect, or are affected by, blood flow mechanics. Vessel geometry and the pulsatile pumping of blood leads to complex flow, which is often difficult to characterize. This article discusses a computational method to better characterize blood flow kinematics. In particular, we compute Lagrangian coherent structures (LCS) to study flow in large vessels. We demonstrate that LCS can be used to characterize flow stagnation, flow separation, partitioning of fluid to downstream vasculature, and mechanisms governing stirring and mixing in vascular models. This perspective allows valuable under-standing of flow features in large vessels beyond methods traditionally considered. PMID:18437573

  19. Vascular anatomy of the developing medaka, Oryzias latipes: a complementary fish model for cardiovascular research on vertebrates.

    PubMed

    Fujita, Misato; Isogai, Sumio; Kudo, Akira

    2006-03-01

    The zebrafish has become a very useful vertebrate model for cardiovascular research, but detailed morphogenetic studies have revealed that it differs from mammals in certain aspects of the primary circulatory system, in particular, the early vitelline circulation. We searched for another teleost species that might serve as a complementary model for the formation of these early primary vessels. Here (and online at http://www.shigen.nig.ac.jp/medaka/atlas/), we present a detailed characterization of the vascular anatomy of the developing medaka embryo from the stage 24 (1 day 20 hr) through stage 30 (3 days 10 hr). Three-dimensional images using confocal microangiography show that the medaka, Oryzias latipes, follows the common embryonic circulatory pattern consisting of ventral aorta, aortic arches, dorsal aorta, transverse vessels, vitelline capillary plexus, and marginal veins. The medaka, thus, may serve as a valuable model system for genetic analysis of the primary vasculature of vertebrates. PMID:16450400

  20. A Systems Biology Approach to Uncovering Pharmacological Synergy in Herbal Medicines with Applications to Cardiovascular Disease

    PubMed Central

    Wang, Xia; Xu, Xue; Tao, Weiyang; Li, Yan; Wang, Yonghua; Yang, Ling

    2012-01-01

    Background. Clinical trials reveal that multiherb prescriptions of herbal medicine often exhibit pharmacological and therapeutic superiority in comparison to isolated single constituents. However, the synergistic mechanisms underlying this remain elusive. To address this question, a novel systems biology model integrating oral bioavailability and drug-likeness screening, target identification, and network pharmacology method has been constructed and applied to four clinically widely used herbs Radix Astragali Mongolici, Radix Puerariae Lobatae, Radix Ophiopogonis Japonici, and Radix Salviae Miltiorrhiza which exert synergistic effects of combined treatment of cardiovascular disease (CVD). Results. The results show that the structural properties of molecules in four herbs have substantial differences, and each herb can interact with significant target proteins related to CVD. Moreover, the bioactive ingredients from different herbs potentially act on the same molecular target (multiple-drug-one-target) and/or the functionally diverse targets but with potentially clinically relevant associations (multiple-drug-multiple-target-one-disease). From a molecular/systematic level, this explains why the herbs within a concoction could mutually enhance pharmacological synergy on a disease. Conclusions. The present work provides a new strategy not only for the understanding of pharmacological synergy in herbal medicine, but also for the rational discovery of potent drug/herb combinations that are individually subtherapeutic. PMID:23243453

  1. Nonlinear systems dynamics in cardiovascular physiology: The heart rate delay map and lower body negative pressure

    NASA Technical Reports Server (NTRS)

    Hooker, John C.

    1990-01-01

    A preliminary study of the applicability of nonlinear dynamic systems analysis techniques to low body negative pressure (LBNP) studies. In particular, the applicability of the heart rate delay map is investigated. It is suggested that the heart rate delay map has potential as a supplemental tool in the assessment of subject performance in LBNP tests and possibly in the determination of susceptibility to cardiovascular deconditioning with spaceflight.

  2. Occupational exposure to noise and the cardiovascular system: A meta-analysis

    Microsoft Academic Search

    G. Tomei; M. Fioravanti; D. Cerratti; A. Sancini; E. Tomao; M. V. Rosati; D. Vacca; T. Palitti; M. Di Famiani; R. Giubilati; S. De Sio; F. Tomei

    2010-01-01

    The aim of our meta-analysis is to evaluate the association between the modifications of the cardiovascular system and chronic exposure to noise in occupationally exposed subjects.We considered the articles published from 1950 to May 2008. Only 15 papers were conforming to the inclusion criteria identified for this meta-analysis. A total of 18,658 workers were divided in three groups according to

  3. What Research Says: The Cardiovascular System: Children's Conceptions and Misconceptions.

    ERIC Educational Resources Information Center

    Arnaudin, Mary W.; Mintzes, Joel J.

    1986-01-01

    Reports findings of a study on children's perceptions and alternate conceptions about the human circulatory system. Summarizes the responses of fifth and eighth grade students on questions dealing with the heart and blood. Offers examples of hands-on activities and confrontation strategies that address common misconceptions on circulation. (ML)

  4. Of mice and men: Sparse statistical modeling in cardiovascular genomics

    Microsoft Academic Search

    David M. Seo; Pascal J. Goldschmidt-Clermont; Mike West

    2007-01-01

    In high-throughput genomics, large-scale designed experiments are becoming common, and analysis approaches based on highly multivariate regression and anova concepts are key tools. Shrinkage models of one form or another can provide comprehensive approaches to the problems of simultaneous inference that involve implicit multiple comparisons over the many, many parameters representing effects of design factors and covariates. We use such

  5. Methodological Issues in Cardiovascular Epidemiology: The Risk of Determining Absolute Risk Through Statistical Models

    PubMed Central

    Panagiotakos, Demosthenes B; Stavrinos, Vassilis

    2006-01-01

    During the past years there has been increasing interest in the development of cardiovascular disease functions that predict future events at individual level. However, this effort has not been so far very successful, since several investigators have reported large differences in the estimation of the absolute risk among different populations. For example, it seems that predictive models that have been derived from US or north European populations overestimate the incidence of cardiovascular events in south European and Japanese populations. A potential explanation could be attributed to several factors such as geographical, cultural, social, behavioral, as well as genetic variations between the investigated populations in addition to various methodological, statistical, issues relating to the estimation of these predictive models. Based on current literature it can be concluded that, while risk prediction of future cardiovascular events is a useful tool and might be valuable in controlling the burden of the disease in a population, further work is required to improve the accuracy of the present predictive models. PMID:17326336

  6. Characterization of Cardiovascular Outcomes in a Type 2 Diabetes Glucose Supply and Insulin Demand Model

    PubMed Central

    Monte, Scott V.; Schentag, Jerome J.; Adelman, Martin H.; Paladino, Joseph A.

    2010-01-01

    Background The nonsignificant reduction in macrovascular outcomes observed in Action to Control Cardiovascular Risk in Diabetes; Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation; and the Veterans Affairs Diabetes Trial have collectively created uncertainty with respect toward the proper extent of blood glucose reduction and also the optimal therapeutic choice to attain the reduction. In the article entitled “Glucose Supply and Insulin Demand Dynamics of Antidiabetic Agents” in this issue of Journal of Diabetes Science and Technology, we presented data for a pharmacokinetic/pharmacodynamic model that characterizes the effect of conventional antidiabetic therapies on the glucose supply and insulin demand dynamic. Here, it is our objective to test the hypothesis that, in conjunction with hemoglobin A1c (HbA1c), patients managed on the glucose supply side of the model would have fewer cardiovascular events versus those managed on the insulin demand side. Methods To test this hypothesis, the electronic medical records of a group model health maintenance organization were queried to compile a population of patients meeting the following inclusion criteria: (1) type 2 diabetes mellitus (T2DM), (2) known date of T2DM diagnosis; (3) ICD-9 or CPT code identification and chart review confirmation of a first major cardiovascular event (myocardial infarction, coronary artery bypass graft, or angioplasty),(4) five years of continuous eligibility, and (5) on antidiabetic therapy at the beginning of the 5-year observation period. These patients were subsequently matched (1:1) to T2DM patients meeting the same criteria who had not experienced an event and were analyzed for differences in glucose control (HbA1C), the glucose supply:insulin demand dynamic (SD ratio), and categorical combinations of both parameters. Results Fifty cardiovascular event patients met inclusion criteria and were matched to controls. No difference was observed for the average HbA1c or SD ratio between patients experiencing an event and controls (7.5 ± 1.0% versus 7.3 ± 0.9%, p = .275, and 1.2 ± 0.3 versus 1.3 ± 0.3, p = .205, respectively). Likewise, for categorical representations, there were no differences in event rate at the pre-identified breakpoints (HbA1c ?7% versus <7%; 72% versus 64%, p = .391, and SD ratio ?1 versus <1; 68% versus 76%, p = .373, ?1.25 versus <1.25; 42% versus 56%, p = .161, ?1.5 versus <1.5; 22% versus 30%, p = .362, respectively). Analyzing the combined effect of glucose control and the SD dynamic, patients managed at higher glucose values and on the insulin demand side of the model (HbA1c ?7% and SD ratio <1.25) tended to have greater cardiovascular risk than those managed at an HbA1c <7%, or HbA1c ?7% with an SD ratio ?1.25 (61% versus 39%; p = .096). Conclusion Independently, more aggressive HbA1c reduction and higher SD ratio values were not independently associated with a reduction in cardiovascular outcomes. Combining the parameters, it would appear that patients managed at higher glucose values and on the insulin demand side of the model may have increased cardiovascular risk. Based on these findings, it is pertinent to conduct subsequent works to refine SD ratio estimates and apply the model to larger, long-term T2DM cardiovascular outcome trials. J Diabetes Sci Technol 2010;4(2):382-390 PMID:20307400

  7. Technological Innovations in the Development of Cardiovascular Clinical Information Systems

    Microsoft Academic Search

    Nan-Chen Hsieh; Chung-Yi Chang; Kuo-Chen Lee; Jeen-Chen Chen; Chien-Hui Chan

    Recent studies have shown that computerized clinical case management and decision support systems can be used to assist surgeons\\u000a in the diagnosis of disease, optimize surgical operation, aid in drug therapy and decrease the cost of medical treatment.\\u000a Therefore, medical informatics has become an extensive field of research and many of these approaches have demonstrated potential\\u000a value for improving medical

  8. Systolic time interval data acquisition system. Specialized cardiovascular studies

    NASA Technical Reports Server (NTRS)

    Baker, J. T.

    1976-01-01

    The development of a data acquisition system for noninvasive measurement of systolic time intervals is described. R-R interval from the ECG determines instantaneous heart rate prior to the beat to be measured. Total electromechanical systole (Q-S2) is measured from the onset of the ECG Q-wave to the onset of the second heart sound (S2). Ejection time (ET or LVET) is measured from the onset of carotid upstroke to the incisure. Pre-ejection period (PEP) is computed by subtracting ET from Q-S2. PEP/ET ratio is computed directly.

  9. A Simple Chinese Risk Score Model for Screening Cardiovascular Autonomic Neuropathy

    PubMed Central

    Zeng, Fangfang; Tang, Zi-Hui; Wang, Ying-Wei

    2014-01-01

    Background The purpose of the present study was to develop and evaluate a risk score to predict people at high risk of cardiovascular autonomic dysfunction neuropathy (CAN) in Chinese population. Methods and Materials A population-based sample of 2,092 individuals aged 30–80 years, without previously diagnosed CAN, was surveyed between 2011 and 2012. All participants underwent short-term HRV test. The risk score was derived from an exploratory set. The risk score was developed by stepwise backward multiple logistic regression. The coefficients from this model were transformed into components of a CAN score. This score was tested in a validation and entire sample. Results The final risk score included age, body mass index, hypertension, resting hear rate, items independently and significantly (P<0.05) associated with the presence of previously undiagnosed CAN. The area under the receiver operating curve was 0.726 (95% CI 0.686–0.766) for exploratory set, 0.784 (95% CI 0.749–0.818) for validation set, and 0.756 (95% CI 0.729–0.782) for entire sample. In validation set, at optimal cutoff score of 5 of 10, the risk score system has the sensitivity, specificity, and percentage that needed subsequent testing were 69, 78, and 30%, respectively. Conclusion We developed a CAN risk score system based on a set of variables not requiring laboratory tests. The score system is simple fast, inexpensive, noninvasive, and reliable tool that can be applied to early intervention to delay or prevent the disease in China. PMID:24621478

  10. Injected nanoparticles: the combination of experimental systems to assess cardiovascular adverse effects.

    PubMed

    Vlasova, Maria A; Tarasova, Olga S; Riikonen, Joakim; Raula, Janne; Lobach, Anatoly S; Borzykh, Anna A; Smirin, Boris V; Kauppinen, Esko I; Eletskii, Alexander V; Herzig, Karl-Heinz; Salonen, Jarno; Tavi, Pasi; Lehto, Vesa-Pekka; Järvinen, Kristiina

    2014-05-01

    When nanocarriers are used for drug delivery they can often achieve superior therapeutic outcomes over standard drug formulations. However, concerns about their adverse effects are growing due to the association between exposure to certain nanosized particles and cardiovascular events. Here we examine the impact of intravenously injected drug-free nanocarriers on the cardiovasculature at both the systemic and organ levels. We combine in vivo and in vitro methods to enable monitoring of hemodynamic parameters in conscious rats, assessments of the function of the vessels after sub-chronic systemic exposure to nanocarriers and evaluation of the direct effect of nanocarriers on vascular tone. We demonstrate that nanocarriers can decrease blood pressure and increase heart rate in vivo via various mechanisms. Depending on the type, nanocarriers induce the dilation of the resistance arteries and/or change the responses induced by vasoconstrictor or vasodilator drugs. No direct correlation between physicochemical properties and cardiovascular effects of nanoparticles was observed. The proposed combination of methods empowers the studies of cardiovascular adverse effects of the nanocarriers. PMID:24530427

  11. OCT imaging of the musculoskeletal and cardiovascular systems

    NASA Astrophysics Data System (ADS)

    Li, Xing D.; Stamper, Debra L.; Patel, Nirlep A.; Saunders, Kathleen; Plummer, Sam; Schenck, John; Rogowska, Ika; Fujimoto, James G.; Brezinski, Mark E.

    2002-07-01

    In this presentation, the application of optical coherence tomography (OCT) to the prevention of myocardial infarction and early identification of osteoarthritis is discussed. Myocardial infarction or a heart attack is the leading cause of death worldwide. It results from an acute loss of blood flow to a region of the heart resulting in death to that heart tissue. Most heart attacks are caused by small, thin walled lipid filled plaques which can not be detected by currently available imaging technologies. This paper outlines some of the advances demonstrating the potential of OCT for the identification of high risk plaque. Osteoarthritis is a major cause of mobility in the industrialized world. The hallmark of the disease is a degradation of articular cartilage. As new therapeutics have been shown to be effective in animal models, there effectiveness in humans remains unclear as there is no effective method for accurate monitoring changes in cartilage. In the second part of this manuscript, the effectiveness of OCT for monitoring articular cartilage is described.

  12. Improving the Prevention of Cardiovascular Disease in Primary Health Care: The Model for Prevention Study Protocol

    PubMed Central

    Davey, Rachel C; Cochrane, Thomas; Williams, Lauren T; Clancy, Tanya

    2014-01-01

    Background Cardiovascular disease (CVD) is the leading cause of death globally, and accounted for nearly 31% of all deaths in Australia in 2011. The primary health care sector is at the frontline for addressing CVD, however, an evidence-to-practice gap exists in CVD risk assessment and management. General practice plays a key role in CVD risk assessment and management, but this sector cannot provide ongoing lifestyle change support in isolation. Community-based lifestyle modification services and programs provided outside the general practice setting have a key role in supporting and sustaining health behavior change. Fostering linkages between the health sector and community-based lifestyle services, and creating sustainable systems that support these sectors is important. Objective The objective of the study Model for Prevention (MoFoP) is to take a case study approach to examine a CVD risk reduction intervention in primary health care, with the aim of identifying the key elements required for an effective and sustainable approach to coordinate CVD risk reduction across the health and community sectors. These elements will be used to consider a new systems-based model for the prevention of CVD that informs future practice. Methods The MoFoP study will use a mixed methods approach, comprising two complementary research elements: (1) a case study, and (2) a pre/post quasi-experimental design. The case study will consider the organizations and systems involved in a CVD risk reduction intervention as a single case. The pre/post experimental design will be used for HeartLink, the intervention being tested, where a single cohort of patients between 45 and 74 years of age (or between 35 and 74 years of age if Aboriginal or Torres Strait Islander) considered to be at high risk for a CVD event will be recruited through general practice, provided with enhanced usual care and additional health behavior change support. A range of quantitative and qualitative data will be collected. This will include individual health and well being data collected at baseline and again at 12 months for HeartLink participants, and systems related data collected over the period of the intervention to inform the case study. Results The intervention is currently underway, with results expected in late 2015. Conclusions Gaining a better understanding of CVD prevention in primary health care requires a research approach that can capture and express its complexity. The MoFoP study aims to identify the key elements for effective CVD prevention across the health and community sectors, and to develop a model to better inform policy and practice in this key health priority area for Australia. PMID:25008232

  13. Short-term couplings of the cardiovascular system in pregnant women suffering from pre-eclampsia.

    PubMed

    Riedl, Maik; Suhrbier, Alexander; Stepan, Holger; Kurths, Jürgen; Wessel, Niels

    2010-05-13

    Pre-eclampsia (PE), a serious pregnancy-specific disorder, causes significant neonatal and maternal morbidity and mortality. Recent studies showed that cardiovascular variability parameters as well as the baroreflex sensitivity remarkably improve its early diagnosis. For a better understanding of the dynamical changes caused by PE, in this study the coupling between respiration, systolic and diastolic blood pressure, and heart rate is investigated. Thirteen datasets of healthy pregnant women and 10 of subjects suffering from PE are included. Nonlinear additive autoregressive models with external input are used for a model-based coupling analysis following the idea of Granger causality. To overcome the problem of misdetections of standard methods in systems with a dominant driver, a heuristic ensemble approach is used here. A coupling is assumed to be real when existent in more than 80 per cent of the ensemble members, and otherwise denoted as artefacts. As the main result, we found that the coupling structure between heart rate, systolic blood pressure, diastolic blood pressure and respiration for healthy subjects and PE patients is the same and reliable. As a pathological mechanism, however, a significant increased respiratory influence on the diastolic blood pressure could be found for PE patients (p=0.003). Moreover, the nonlinear form of the respiratory influence on the heart rate is significantly different between the two groups (p=0.002). Interestingly, the influence of systolic blood pressure on the heart rate is not selected, which indicates that the baroreflex sensitivity estimation strongly demands the consideration of causal relationships between heart rate, blood pressure and respiration. Finally, our results point to a potential role of respiration for understanding the pathogenesis of PE. PMID:20368244

  14. Cardiovascular Actions of Neurotrophins

    PubMed Central

    CAPORALI, ANDREA; EMANUELI, COSTANZA

    2010-01-01

    Neurotrophins were christened in consideration of their actions on the nervous system and, for a long time, they were the exclusive interest of neuroscientists. However, more recently, this family of proteins has been shown to possess essential cardiovascular functions. During cardiovascular development, neurotrophins and their receptors are essential factors in the formation of the heart and critical regulator of vascular development. Postnatally, neurotrophins control the survival of endothelial cells, vascular smooth muscle cells, and cardiomyocytes and regulate angiogenesis and vasculogenesis, by autocrine and paracrine mechanisms. Recent studies suggest the capacity of neurotrophins, via their tropomyosin-kinase receptors, to promote therapeutic neovascularization in animal models of hindlimb ischemia. Conversely, the neurotrophin low-affinity p75NTR receptor induces apoptosis of endothelial cells and vascular smooth muscle cells and impairs angiogenesis. Finally, nerve growth factor looks particularly promising in treating microvascular complications of diabetes or reducing cardiomyocyte apoptosis in the infarcted heart. These seminal discoveries have fuelled basic and translational research and thus opened a new field of investigation in cardiovascular medicine and therapeutics. Here, we review recent progress on the molecular signaling and roles played by neurotrophins in cardiovascular development, function, and pathology, and we discuss therapeutic potential of strategies based on neurotrophin manipulation. PMID:19126759

  15. Clinical Perspectives and Fundamental Aspects of Local Cardiovascular and Renal Renin-Angiotensin Systems

    PubMed Central

    De Mello, Walmor C.; Frohlich, Edward D.

    2014-01-01

    Evidence for the potential role of organ specific cardiovascular renin–angiotensin systems (RAS) has been demonstrated experimentally and clinically with respect to certain cardiovascular and renal diseases. These findings have been supported by studies involving pharmacological inhibition during ischemic heart disease, myocardial infarction, cardiac failure; hypertension associated with left ventricular ischemia, myocardial fibrosis and left ventricular hypertrophy; structural and functional changes of the target organs associated with prolonged dietary salt excess; and intrarenal vascular disease associated with end-stage renal disease. Moreover, the severe structural and functional changes induced by these pathological conditions can be prevented and reversed by agents producing RAS inhibition (even when not necessarily coincident with alterations in arterial pressure). In this review, we discuss specific fundamental and clinical aspects and mechanisms related to the activation or inhibition of local RAS and their implications for cardiovascular and renal diseases. Fundamental aspects involving the role of angiotensins on cardiac and renal functions including the expression of RAS components in the heart and kidney and the controversial role of angiotensin-converting enzyme 2 on angiotensin peptide metabolism in humans, were discussed. PMID:24600438

  16. Induced pluripotent stem cell-derived cardiomyocytes for cardiovascular disease modeling and drug screening

    PubMed Central

    2013-01-01

    Human induced pluripotent stem cells (hiPSCs) have emerged as a novel tool for drug discovery and therapy in cardiovascular medicine. hiPSCs are functionally similar to human embryonic stem cells (hESCs) and can be derived autologously without the ethical challenges associated with hESCs. Given the limited regenerative capacity of the human heart following myocardial injury, cardiomyocytes derived from hiPSCs (hiPSC-CMs) have garnered significant attention from basic and translational scientists as a promising cell source for replacement therapy. However, ongoing issues such as cell immaturity, scale of production, inter-line variability, and cell purity will need to be resolved before human clinical trials can begin. Meanwhile, the use of hiPSCs to explore cellular mechanisms of cardiovascular diseases in vitro has proven to be extremely valuable. For example, hiPSC-CMs have been shown to recapitulate disease phenotypes from patients with monogenic cardiovascular disorders. Furthermore, patient-derived hiPSC-CMs are now providing new insights regarding drug efficacy and toxicity. This review will highlight recent advances in utilizing hiPSC-CMs for cardiac disease modeling in vitro and as a platform for drug validation. The advantages and disadvantages of using hiPSC-CMs for drug screening purposes will be explored as well. PMID:24476344

  17. Significance of the Development of a Cardiovascular Disease Surveillance and Reporting System in India

    PubMed Central

    Coelho, Ken Russell

    2013-01-01

    Cardiovascular disease (CVD) is the single largest cause of global morbidity and mortality and is the leading cause of death in the Indian subcontinent projected to contribute to deaths expected to double by 2015. The social and economic impact of these staggering projections highlight the need for a centralized effort to monitor and evaluate behavioral and physiological risk factors for CVD. Limited evidence on existing surveillance systems suggest that the key to an effective monitoring and evaluation (M and E) program for CVD surveillance in India relies upon the World Health Organization's STEP-wise model. Key recommendations for the Ministry of Health include the development of a national CVD surveillance program with expertise and a quality-improvement mechanism to receive continuous input from similar surveillance programs in likeminded countries. Structure of the surveillance system would include; (1) the development of process measures for CVD risk factor’ based surveillance M and E systems for early detection of CVD at the local-level, (2) the development of trigger based data reporting responsibilities to State-based monitoring teams including incentives for accuracy in data reporting and the use of data-driven evidence to target risk specific intervention and prevention on Central Government monitoring teams with reporting feedback to the State and local-levels and (3) the creation of health policy to require the use of data to target risk specific prevention for intervention and developing local technical capacity. Such a system would provide significant cost and social benefits, presenting an evidence based data driven cost-effective business case for scale-up and potential use in areas comprising similar demographics. Future research should focus on the inclusion of a systematic critique of the reported data for the challenges to surveillance systems in India and the examination of the effect of an incentivized reporting system on the states. Further inquiry into the types of reporting and lessons from other countries’ surveillance programs with alternative strategies to a national approach should address potential imitations at the ground or peripheral levels. PMID:24347902

  18. Lack of cardiovascular risk assessment in inflammatory arthritis and systemic lupus erythematosus patients at a tertiary care center

    Microsoft Academic Search

    Stephanie O. Keeling; Michelle Teo; Daisy Fung

    The purpose of this study is to evaluate cardiovascular risk assessment at a Canadian rheumatology center and describe the\\u000a cardiovascular risk of inflammatory arthritis (IA) and systemic lupus erythematosus (SLE) patients using the Framingham risk\\u000a score. A retrospective chart review of 504 patients attending nine rheumatology practices at the University of Alberta Hospital\\u000a was performed. A pre-specified case report form

  19. Air pollution and autonomic and vascular dysfunction in patients with cardiovascular disease: interactions of systemic inflammation, overweight, and gender.

    PubMed

    Huang, Wei; Zhu, Tong; Pan, Xiaochuan; Hu, Min; Lu, Shou-En; Lin, Yong; Wang, Tong; Zhang, Yuanhang; Tang, Xiaoyan

    2012-07-15

    The authors conducted a 2-year follow-up of 40 cardiovascular disease patients (mean age = 65.6 years (standard deviation, 5.8)) who underwent repeated measurements of cardiovascular response before and during the 2008 Beijing Olympics (Beijing, China), when air pollution was strictly controlled. Ambient levels of particulate matter with an aerodynamic diameter less than 2.5 µm (PM(2.5)), black carbon, nitrogen dioxide, sulfur dioxide, ozone, and carbon monoxide were measured continuously, with validation of concurrent real-time measurements of personal exposure to PM(2.5) and carbon monoxide. Linear mixed-effects models were used with adjustment for individual risk factors, time-varying factors, and meteorologic effects. Significant heart rate variability reduction and blood pressure elevation were observed in association with exposure to air pollution. Specifically, interquartile-range increases of 51.8 µg/m(3), 2.02 µg/m(3), and 13.7 ppb in prior 4-hour exposure to PM(2.5), black carbon, and nitrogen dioxide were associated with significant reductions in the standard deviation of the normal-to-normal intervals of 4.2% (95% confidence interval (CI): 1.9, 6.4), 4.2% (95% CI: 1.8, 6.6), and 3.9% (95% CI: 2.2, 5.7), respectively. Greater heart rate variability declines were observed among subjects with C-reactive protein values above the 90th percentile, subjects with a body mass index greater than 25, and females. The authors conclude that autonomic and vascular dysfunction may be one of the mechanisms through which air pollution exposure can increase cardiovascular disease risk, especially among persons with systemic inflammation and overweight. PMID:22763390

  20. Can oral vitamin D prevent the cardiovascular diseases among migrants in Australia? Provider perspective using Markov modelling.

    PubMed

    Ruwanpathirana, Thilanga; Owen, Alice; Renzaho, Andre Mn; Zomer, Ella; Gambhir, Manoj; Reid, Christopher M

    2015-06-01

    The study was designed to model the effectiveness and cost effectiveness of oral Vitamin D supplementation as a primary prevention strategy for cardiovascular disease among a migrant population in Australia. It was carried out in the Community Health Service, Kensington, Melbourne. Best-case scenario analysis using a Markov model was employed to look at the health care providers' perspective. Adult migrants who were vitamin D deficient and free from cardiovascular disease visiting the medical centre at least once during the period from 1 January 2010 to 31 December 2012 were included in the study. The blood pressure-lowering effect of vitamin D was taken from a published meta-analysis and applied in the Framingham 10 year cardiovascular risk algorithm (with and without oral vitamin D supplements) to generate the probabilities of cardiovascular events. A Markov decision model was used to estimate the provider costs associated with the events and treatments. Uncertainties were derived by Monte Carlo simulation. Vitamin D oral supplementation (1000 IU/day) for 10 years could potentially prevent 31 (interquartile range (IQR) 26 to 37) non-fatal and 11 (IQR 10 to 15) fatal cardiovascular events in a migrant population of 10 000 assuming 100% compliance. The provider perspective incremental cost effectiveness per year of life saved was AU$3,992 (IQR 583 to 8558). This study suggests subsidised supplementation of oral vitamin D may be a cost effective intervention to reduce non-fatal and fatal cardiovascular outcomes in high-risk migrant populations. PMID:25854647

  1. Model-Based Assessment of Cardiovascular Autonomic Control in Children with Obstructive Sleep Apnea

    PubMed Central

    Chaicharn, Jarree; Lin, Zheng; Chen, Maida L.; Ward, Sally L.D.; Keens, Thomas; Khoo, Michael C. K.

    2009-01-01

    Study Objectives: To quantitatively assess daytime autonomic cardiovascular control in pediatric subjects with and without obstructive sleep apnea syndrome (OSAS). Design: Respiration, R-R intervals, and noninvasive continuous blood pressure were monitored in awake subjects in the supine and standing postures, as well as during cold face stimulation. Setting: Sleep disorders laboratory in a hospital setting. Participants: Ten pediatric patients (age 11.4 ± 3.6 years) with moderate to severe OSAS (obstructive apnea-hypopnea index = 21.0 ± 6.6/ h) before treatment and 10 age-matched normal control subjects (age 11.5 ± 3.7 years). Measurements and Results: Spectral analysis of heart rate variability revealed that high-frequency power was similar and the ratio of low- to high-frequency power was lower in subjects with OSAS vs control subjects. The closed-loop minimal model allowed heart rate variability to be partitioned into a component mediated by respiratory-cardiac coupling and a baroreflex component, whereas blood pressure variability was assumed to result from the direct effects of respiration and fluctuations in cardiac output. Baroreflex gain was lower in subjects with OSAS vs control subjects. Under orthostatic stress, respiratory-cardiac coupling gain decreased in both subject groups, but baroreflex gain decreased only in controls. The model was extended to incorporate time-varying parameter changes for analysis of the data collected during cold face stimulation: cardiac output gain increased in controls but remained unchanged in OSAS. Conclusions: Our findings suggest that vagal modulation of the heart remains relatively normal in pediatric subjects with OSAS. However, baseline cardiovascular sympathetic activity is elevated, and reactivity to autonomic challenges is impaired. Citation: Chaicharn J; Lin Z; Chen ML; Ward SLD; Keens T; Khoo MCK. Model-based assessment of cardiovascular autonomic control in children with obstructive sleep apnea. SLEEP 2009;32(7):927-938. PMID:19639756

  2. Women with cardiovascular risk after preeclampsia: is there follow-up within the Unified Health System in Brazil?

    PubMed Central

    da Silva, Maria de Lourdes Costa; Galvão, Ana Cristina Araújo de Andrade; de Souza, Nilba Lima; de Azevedo, George Dantas; Jerônimo, Selma Maria Bezerra; de Araújo, Ana Cristina Pinheiro Fernandes

    2014-01-01

    Objectives to identify women with cardiovascular risk, five years after a preeclampsic episode (PE), and identify the follow-up of these women within the Unified Health System (Sistema Único de Saúde - SUS), in the city of Natal/RN. Methods a quantitative and exploratory study conducted at the Januário Cicco University Maternity Ward/RN. The sample consisted of 130 women, 65 with a PE episode and 65 who were normotensive. Results we found statistical significance with regard to body mass index, weight, family history of cardiovascular disease (CVD) and cardiovascular complications when comparing women with previous PE to normotensive women. The groups were unaware of their cardiovascular risk factors and, in addition, they reported difficulties in accessing primary health care (PHC) services. Conclusions women with a PE history are at increased risk of developing CVD, unaware of late PE complications, and lacked customized care when compared to normotensive patients. PMID:24553708

  3. The circadian organization of the cardiovascular system in health and disease.

    PubMed

    Portaluppi, Francesco

    2014-05-01

    In normal conditions, the temporal organization of blood pressure (BP) is mainly controlled by neuroendocrine mechanisms. Above all, the monoaminergic systems (including variations in activity of the autonomous nervous system, and in secretion of biogenic amines) appear to integrate the major driving factors of temporal variability, but evidence is available also for a role of the hypothalamic-pituitary-adrenal, hypothalamic-pituitary-thyroid, opioid, renin-angiotensin-aldosterone, and endothelial systems, as well as other vasoactive peptides. Many hormones with established actions on the cardiovascular system (arginine vasopressin, vasoactive intestinal peptide, melatonin, somatotropin, insulin, steroids, serotonin, CRF, ACTH, TRH, endogenous opioids, and prostaglandin E2) are also involved in sleep induction or arousal, which in turn affects BP regulation. Hence, physical, mental, and pathological stimuli which may drive activation or inhibition of these neuroendocrine effectors of biological rhythmicity, may also interfere with the temporal BP structure. On the other hand, the immediate adaptation of the exogenous components of BP rhythms to the demands of the environment are modulated by the circadian-time-dependent responsiveness of the biological oscillators and their neuroendocrine effectors. These notions may contribute to a better understanding of the pathophysiology and therapeutics of hypertension, myocardial ischemia and infarction, cardiac arrhythmias and all kind of acute cardiovascular accidents. For instance, the normal temporal balance between external stimuli and neurohumoral influences with endogenous rhythmicity is preserved in uncomplicated, essential hypertension, whereas it is frequently lost in complicated and secondary forms of hypertension where gross alterations are found in the circadian profile of BP. When all the gates of the critical physiologic functions are aligned at the same time, the susceptibility, and thus risk, of adverse events becomes extremely high, even in the presence of minor environmental stimuli that could be usually harmless, and circadian rhythms of cardiovascular events are observed. This implies that one cannot afford to miss what happens during day but also night. Moreover, the requirement for preventive and therapeutic interventions varies predictably during the 24 h, suggesting that the delivery of protective or preventive medications should be synchronized in time in proportion to need, as determined by established rhythmic patterns in cardiovascular function as well as risk, in a manner that will avert or minimize their undesired side effects. PMID:24851400

  4. Reproduction of continuous flow left ventricular assist device experimental data by means of a hybrid cardiovascular model with baroreflex control.

    PubMed

    Fresiello, Libera; Zieli?ski, Krzysztof; Jacobs, Steven; Di Molfetta, Arianna; Pa?ko, Krzysztof Jakub; Bernini, Fabio; Martin, Michael; Claus, Piet; Ferrari, Gianfranco; Trivella, Maria Giovanna; Górczy?ska, Krystyna; Darowski, Marek; Meyns, Bart; Kozarski, Maciej

    2014-06-01

    Long-term mechanical circulatory assistance opened new problems in ventricular assist device-patient interaction, especially in relation to autonomic controls. Modeling studies, based on adequate models, could be a feasible approach of investigation. The aim of this work is the exploitation of a hybrid (hydronumerical) cardiovascular simulator to reproduce and analyze in vivo experimental data acquired during a continuous flow left ventricular assistance. The hybrid cardiovascular simulator embeds three submodels: a computational cardiovascular submodel, a computational baroreflex submodel, and a hydronumerical interface submodel. The last one comprises two impedance transformers playing the role of physical interfaces able to provide a hydraulic connection with specific cardiovascular sites (in this article, the left atrium and the ascending/descending aorta). The impedance transformers are used to connect a continuous flow pump for partial left ventricular support (Synergy Micropump, CircuLite, Inc., Saddlebrooke, NJ, USA) to the hybrid cardiovascular simulator. Data collected from five animals in physiological, pathological, and assisted conditions were reproduced using the hybrid cardiovascular simulator. All parameters useful to characterize and tune the hybrid cardiovascular simulator to a specific hemodynamic condition were extracted from experimental data. Results show that the simulator is able to reproduce animal-specific hemodynamic status both in physiological and pathological conditions, to reproduce cardiovascular left ventricular assist device (LVAD) interaction and the progressive unloading of the left ventricle for different pump speeds, and to investigate the effects of the LVAD on baroreflex activity. Results in chronic heart failure conditions show that an increment of LVAD speed from 20?000 to 22?000?rpm provokes a decrement of left ventricular flow of 35% (from 2 to 1.3?L/min). Thanks to its flexibility and modular structure, the simulator is a platform potentially useful to test different assist devices, thus providing clinicians additional information about LVAD therapy strategy. PMID:24117988

  5. Targeting heme oxygenase: therapeutic implications for diseases of the cardiovascular system.

    PubMed

    Peterson, Stephen J; Frishman, William H; Abraham, Nader G

    2009-01-01

    Heme oxygenase (HO) is important in attenuating the overall production of reactive oxygen species through its ability to degrade heme and to produce carbon monoxide, biliverdin/bilirubin, and release of free iron. Excess free heme catalyzes the formation of reactive oxygen species, which leads to endothelial cell (EC) dysfunction as seen in numerous pathologic vascular conditions including systemic hypertension and diabetes, as well as in ischemia/reperfusion injury.The up-regulation of HO-1 can be achieved through the use of pharmaceutical agents such as metalloporphyrins and statins. In addition, atrial natriuretic peptide and nitric oxide donors are important modulators of the heme-HO system, either through induction of HO-1 or the increased biologic activity of its products. Gene therapy and gene transfer, including site- and organ-specific targeted gene transfer have become powerful tools for studying the potential role of the 2 isoforms of HO, HO-1/HO-2, in the treatment of cardiovascular disease, as well as diabetes. HO-1 induction by pharmacological agents or the in vitro gene transfer of human HO-1 into ECs increases cell cycle progression and attenuates angiotensin II, tumor necrosis factor-alpha, and heme-mediated DNA damage; administration in vivo corrects blood pressure elevation after angiotensin II exposure. Delivery of human HO-1 to hyperglycemic rats significantly lowers superoxide levels and prevents EC damage and sloughing of vascular EC into the circulation. In addition, administration of human HO-1 to rats in advance of ischemia/reperfusion injury considerably reduces tissue damage.The ability to up-regulate HO-1 either through pharmacological means or through the use of gene therapy may offer therapeutic strategies for the prevention of cardiovascular disease in the future. This review discusses the implications of HO-1 delivery during the early stages of cardiovascular system injury or in early vascular pathology, and suggests that pharmacological agents that regulate HO activity or HO-1 gene delivery itself may become powerful tools for preventing the onset or progression of various cardiovascular diseases. PMID:19384082

  6. Study of nanosensor systems for hypertension associated cerebrovascular and cardiovascular disorders

    NASA Astrophysics Data System (ADS)

    Ramasamy, Mouli; Varadan, Vijay K.

    2015-04-01

    Hypertension and hypertension associated cerebrovascular and cardiovascular diseases are on a rise. At-least 970 million people in the world and Seventy percent of the American adults are affected by high blood pressure, also known as hypertension. Even though blood pressure monitoring systems are readily available, the number of people being affected has been increasing. Most of the blood pressure monitoring systems require cumbersome approaches. Even the noninvasive techniques have not lowered the number of people affected nor did at-least increase the user base of these systems. Uncontrolled or untreated hypertension may lead to various cerebrovascular disorders including stroke, hypertensive crisis, lacunar infarcts intracerebral damage, microaneurysm, and cardiovascular disorders including heart failure, myocardial infraction, and ischemic heart disease. Hypertension is rated as the one of the most important causes of premature death in spite of the technical advances in biomedical technology. This paper briefs a review of the widely adopted blood pressure monitoring methods, research techniques, and finally, proposes a concept of implementing nanosensors and wireless communication for real time non-invasive blood pressure monitoring.

  7. The fentanyl/etomidate-anaesthetised beagle (FEAB) dog: a versatile in vivo model in cardiovascular safety research.

    PubMed

    Van Deuren, Bruno; Van Ammel, Karel; Somers, Yves; Cools, Frank; Straetemans, Roel; van der Linde, Henk J; Gallacher, David J

    2009-01-01

    The purpose of conducting cardiovascular safety pharmacology studies is to investigate the pharmacological profiles of new molecular entities (NMEs) and provide data that can be used for optimization of a possible new drug, and help make a selection of NMEs for clinical development. An anaesthetised dog preparation has been used for more than two decades by our department to measure multiple cardiovascular and respiratory parameters and to evaluate different scientific models, leading to more in-depth evaluation of drug-induced cardiovascular effects. An anaesthetic regime developed in house (induction with lofentanil, scopolamine and succinylcholine, and maintenance with fentanyl and etomidate) gives us a preparation free of pain and stress, with minimal effects on the cardiovascular system. This anaesthetic regime had minimal influences on circulating catecholamine levels, on the baroreflex sensitivity, and on all measured basal parameters compared to conscious dogs. All parameters were stable for at least 3 h, with acceptable tolerance intervals, evaluated over 99 safety studies with 3 vehicle treatments (saline, 10% and 20% hydroxypropyl-beta-cyclodextrin). This translates into a highly sensitive model for detecting possible drug-induced effects of NMEs with different mechanisms of action such as: Ca-, Na-, I(Kr)-, I(Ks)-channel blockers, K- and Ca-channel activators, alpha1- and beta-agonists, and muscarinic antagonists. Fentanyl in combination with etomidate is a successful anaesthetic regime in humans [Stockham, R.J., Stanley, T.H., Pace, N.L., King, K., Groen, F. & Gillmor, S.T. (1987). Induction of anaesthesia with fentanyl or fentanyl plus etomidate in high-risk patients. Journal of Cardiothoracic Anesthesia. 1(1), 19-23.]. In the anaesthetised dog, QT correction factors (Van de Water correction and body temperature correction) and risk factors (total, short-term and long-term instability) have been evaluated, using this regime [Van de Water, A., Verheyen, J., Xhonneux, R. & Reneman, R. (1989). An improved method to correct the QT interval of the electrocardiogram for changes in heart rate. Journal of Pharmacological Methods, 22, 207-217.; van der Linde, H.J., Van Deuren, B., Teisman, A., Towart, R. & Gallacher, D.J. (2008). The effect of changes in core body temperature on the QT interval in beagle dogs: A previously ignored phenomenon, with a method for correction. British Journal of Pharmacology, 154, 1474-1481.; van der Linde, H.J., Van de Water, A., Loots, W., Van Deuren, B., Lu, H.R., Van Ammel, K., et al. (2005) A new method to calculate the beat-to-beat instability of QT duration in drug-induced long QT in anaesthetised dogs. Journal of Pharmacological and Toxicological Methods, 52, 168-177.]. Furthermore, this anaesthetic protocol has been used to create different scientific models (long QT, short QT) with different specific end-points (ventricular fibrillation, adrenergic- or pause-dependent TdP) and also their specific precursors: e.g. aftercontractions, phase 2 EADs, phase 3 EADs, DADs, T-wave morphology changes, T-wave alternans, R-on-T, transmural and interventricular dispersion [Gallacher, D.J., Van de Water, A., van der Linde, H.J., Hermans, A.N., Lu, H.R., Towart, R., et al. (2007). In vivo mechanisms precipitating torsade de pointes in canine model of drug-induced long QT1 syndrome. Cardiovascular Research, 76-2, 247-256.]. This paper gives a brief overview of the stability, reproducibility, sensitivity and utility of a well-validated anaesthetised dog model. PMID:19422925

  8. Qualitative-fuzzy decision support system for monitoring patients with cardiovascular risk

    Microsoft Academic Search

    Cesar Uribe; Claudia Isaza; Jose F. Florez-Arango

    2011-01-01

    Cardiovascular diseases are increasingly common in many countries. Cardiovascular risk (CVR) patients can continue their daily activities, but they must be monitored continuously in order to detect and respond to cardiovascular emergencies in the shortest possible time. Monitoring provides information to the medical personnel, which helps them make a diagnosis and decide upon a tailored treatment. This paper proposes a

  9. Structural identifiability analysis and reparameterisation (parameter reduction) of a cardiovascular feedback model.

    PubMed

    Cheung, S Y Amy; Majid, Oneeb; Yates, James W T; Aarons, Leon

    2012-07-16

    Structural identifiability should be considered when developing mathematical models. A globally or at least locally identifiable model has to be obtained in order to have some chance of obtaining unique parameter estimates when real data are available. An indicator of structural unidentifiability may be that some unknown parameter estimates are found to be not well determined from parameter estimation of a model. An example is discussed in this paper to illustrate the procedures involved when such situations arise. Problems with parameter estimation were observed for a PKPD model for an ?1A/1L-adrenoceptor partial agonist developed for the treatment of stress urinary incontinence The regulation of the side effects of the increased peripheral resistance, induced by the constriction of the blood vessels, was modelled by adapting a previous cardiovascular nonlinear PKPD model proposed by Franchetau and co-workers. Structural identifiability analysis confirmed that the model was unidentifiable. The model was then reparameterised (parameter list reduction) to obtain a globally identifiable model. Simulation studies confirm the superiority of the reduced parameterisation with respect to parameter estimation. The simulation study also confirms the models behave indistinguishably with respect to the input-output behaviour. The example demonstrates the importance of recognising an unidentifiable model and illustrates step by step identifiability analysis, reparameterisation and validation of reparameterised model against the original model. PMID:22343490

  10. High sensitivity C-reactive protein, disease activity and cardiovascular risk factors in systemic lupus erythematosus

    PubMed Central

    Mok, CC; Birmingham, Daniel J.; Ho, Ling Yin; Hebert, Lee A; Rovin, Brad H

    2012-01-01

    Objectives To study the level of high-sensitivity C-reactive protein (hsCRP) and its relationship with disease activity, damage and cardiovascular risk factors in patients with systemic lupus erythematosus (SLE). Method Consecutive patients who fulfilled ?4 ACR criteria for SLE but did not have concurrent infection were recruited. Blood was assayed for hsCRP and disease activity, organ damage of SLE and cardiovascular risk factors were assessed. Linear regression was performed for the relationship among hsCRP, SLE activity, damage and cardiovascular risk factors. Results 289 patients were studied (94% women; age 39.0±13.1 years; SLE duration 7.8±6.7 years). The mean SLEDAI score was 4.9±5.6 and clinically active SLE was present in 122(42%) patients. The mean hsCRP level was 4.87±12.7mg/L, and 28(23%) patients with active SLE had undetectable hsCRP (<0.3mg/L). Linear regression revealed a significant correlation between hsCRP and musculoskeletal (Beta=0.21), hematological (Beta=0.19), serosal (Beta=0.46) and clinical SLEDAI score (Beta=0.24), adjusting for age, sex, body mass index, creatinine and the use of various medications (p<0.005 in all). Levels of hsCRP correlated significantly with anti-dsDNA titer (Beta=0.33;p<0.001) but not with complement C3 (Beta=0.07;p=0.26). Significantly more patients with hsCRP >3.0mg/L were men and chronic smokers, and had diabetes mellitus, higher atherogenic index and history of arterial thrombosis. hsCRP levels correlated significantly with pulmonary and endocrine damage score. Conclusions hsCRP is detectable in 77% of SLE patients with clinically active disease and correlates with SLEDAI scores, particularly serositis and in the musculoskeletal and hematological systems. Elevated hsCRP in SLE is associated with certain cardiovascular risk factors and history of arterial thromboembolism. PMID:22949303

  11. Role of MicroRNAs in Renin-Angiotensin-Aldosterone System-Mediated Cardiovascular Inflammation and Remodeling

    PubMed Central

    Tchounwou, Paul B.

    2015-01-01

    MicroRNAs are endogenous regulators of gene expression either by inhibiting translation or protein degradation. Recent studies indicate that microRNAs play a role in cardiovascular disease and renin-angiotensin-aldosterone system- (RAAS-) mediated cardiovascular inflammation, either as mediators or being targeted by RAAS pharmacological inhibitors. The exact role(s) of microRNAs in RAAS-mediated cardiovascular inflammation and remodeling is/are still in early stage of investigation. However, few microRNAs have been shown to play a role in RAAS signaling, particularly miR-155, miR-146a/b, miR-132/122, and miR-483-3p. Identification of specific microRNAs and their targets and elucidating microRNA-regulated mechanisms associated RAS-mediated cardiovascular inflammation and remodeling might lead to the development of novel pharmacological strategies to target RAAS-mediated vascular pathologies. This paper reviews microRNAs role in inflammatory factors mediating cardiovascular inflammation and RAAS genes and the effect of RAAS pharmacological inhibition on microRNAs and the resolution of RAAS-mediated cardiovascular inflammation and remodeling. Also, this paper discusses the advances on microRNAs-based therapeutic approaches that may be important in targeting RAAS signaling.

  12. Comparing the cardiovascular therapeutic indices of glycopyrronium and tiotropium in an integrated rat pharmacokinetic, pharmacodynamic and safety model.

    PubMed

    Trifilieff, Alexandre; Ethell, Brian T; Sykes, David A; Watson, Kenny J; Collingwood, Steve; Charlton, Steven J; Kent, Toby C

    2015-08-15

    Long acting inhaled muscarinic receptor antagonists, such as tiotropium, are widely used as bronchodilator therapy for chronic obstructive pulmonary disease (COPD). Although this class of compounds is generally considered to be safe and well tolerated in COPD patients the cardiovascular safety of tiotropium has recently been questioned. We describe a rat in vivo model that allows the concurrent assessment of muscarinic antagonist potency, bronchodilator efficacy and a potential for side effects, and we use this model to compare tiotropium with NVA237 (glycopyrronium bromide), a recently approved inhaled muscarinic antagonist for COPD. Anaesthetized Brown Norway rats were dosed intratracheally at 1 or 6h prior to receiving increasing doses of intravenous methacholine. Changes in airway resistance and cardiovascular function were recorded and therapeutic indices were calculated against the ED50 values for the inhibition of methacholine-induced bronchoconstriction. At both time points studied, greater therapeutic indices for hypotension and bradycardia were observed with glycopyrronium (19.5 and 28.5 fold at 1h; >200 fold at 6h) than with tiotropium (1.5 and 4.2 fold at 1h; 4.6 and 5.5 fold at 6h). Pharmacokinetic, protein plasma binding and rat muscarinic receptor binding properties for both compounds were determined and used to generate an integrated model of systemic M2 muscarinic receptor occupancy, which predicted significantly higher M2 receptor blockade at ED50 doses with tiotropium than with glycopyrronium. In our preclinical model there was an improved safety profile for glycopyrronium when compared with tiotropium. PMID:26026369

  13. Three-dimensional optical coherence tomography of the embryonic murine cardiovascular system

    NASA Astrophysics Data System (ADS)

    Luo, Wei; Marks, Daniel L.; Ralston, Tyler S.; Boppart, Stephen A.

    2006-03-01

    Optical coherence tomography (OCT) is an emerging high-resolution real-time biomedical imaging technology that has potential as a novel investigational tool in developmental biology and functional genomics. In this study, murine embryos and embryonic hearts are visualized with an OCT system capable of 2-µm axial and 15-µm lateral resolution and with real-time acquisition rates. We present, to our knowledge, the first sets of high-resolution 2- and 3-D OCT images that reveal the internal structures of the mammalian (murine) embryo (E10.5) and embryonic (E14.5 and E17.5) cardiovascular system. Strong correlations are observed between OCT images and corresponding hematoxylin- and eosin-stained histological sections. Real-time in vivo embryonic (E10.5) heart activity is captured by spectral-domain optical coherence tomography, processed, and displayed at a continuous rate of five frames per second. With the ability to obtain not only high-resolution anatomical data but also functional information during cardiovascular development, the OCT technology has the potential to visualize and quantify changes in murine development and in congenital and induced heart disease, as well as enable a wide range of basic in vitro and in vivo research studies in functional genomics.

  14. Modeling the impact of scaffold architecture and mechanical loading on collagen turnover in engineered cardiovascular tissues.

    PubMed

    Argento, G; de Jonge, N; Söntjens, S H M; Oomens, C W J; Bouten, C V C; Baaijens, F P T

    2015-06-01

    The anisotropic collagen architecture of an engineered cardiovascular tissue has a major impact on its in vivo mechanical performance. This evolving collagen architecture is determined by initial scaffold microstructure and mechanical loading. Here, we developed and validated a theoretical and computational microscale model to quantitatively understand the interplay between scaffold architecture and mechanical loading on collagen synthesis and degradation. Using input from experimental studies, we hypothesize that both the microstructure of the scaffold and the loading conditions influence collagen turnover. The evaluation of the mechanical and topological properties of in vitro engineered constructs reveals that the formation of extracellular matrix layers on top of the scaffold surface influences the mechanical anisotropy on the construct. Results show that the microscale model can successfully capture the collagen arrangement between the fibers of an electrospun scaffold under static and cyclic loading conditions. Contact guidance by the scaffold, and not applied load, dominates the collagen architecture. Therefore, when the collagen grows inside the pores of the scaffold, pronounced scaffold anisotropy guarantees the development of a construct that mimics the mechanical anisotropy of the native cardiovascular tissue. PMID:25319256

  15. Cardiovascular Autonomic Nervous System Function and Aerobic Capacity in Type 1 Diabetes

    PubMed Central

    Hägglund, Harriet; Uusitalo, Arja; Peltonen, Juha E.; Koponen, Anne S.; Aho, Jyrki; Tiinanen, Suvi; Seppänen, Tapio; Tulppo, Mikko; Tikkanen, Heikki O.

    2012-01-01

    Impaired cardiovascular autonomic nervous system (ANS) function has been reported in type 1 diabetes (T1D) patients. ANS function, evaluated by heart rate variability (HRV), systolic blood pressure variability (SBPV), and baroreflex sensitivity (BRS), has been linked to aerobic capacity (VO2peak) in healthy subjects, but this relationship is unknown in T1D. We examined cardiovascular ANS function at rest and during function tests, and its relations to VO2peak in T1D individuals. Ten T1D patients (34?±?7?years) and 11 healthy control (CON; 31?±?6?years) age and leisure-time physical activity-matched men were studied. ANS function was recorded at rest and during active standing and handgrip. Determination of VO2peak was obtained with a graded cycle ergometer test. During ANS recordings SBPV, BRS, and resting HRV did not differ between groups, but alpha1 responses to maneuvers in detrended fluctuation analyses were smaller in T1D (active standing; 32%, handgrip; 20%, medians) than in CON (active standing; 71%, handgrip; 54%, p?cardiovascular ANS function at rest compared with CON. Resting parasympathetic cardiac activity correlated with VO2peak in CON but not in T1D. Detrended fluctuation analysis could be a sensitive detector of changes in cardiac ANS function in T1D. PMID:22973238

  16. Milan PM1 Induces Adverse Effects on Mice Lungs and Cardiovascular System

    PubMed Central

    Farina, Francesca; Sancini, Giulio; Longhin, Eleonora; Mantecca, Paride; Camatini, Marina; Palestini, Paola

    2013-01-01

    Recent studies have suggested a link between inhaled particulate matter (PM) exposure and increased mortality and morbidity associated with cardiorespiratory diseases. Since the response to PM1 has not yet been deeply investigated, its impact on mice lungs and cardiovascular system is here examined. A repeated exposure to Milan PM1 was performed on BALB/c mice. The bronchoalveolar lavage fluid (BALf) and the lung parenchyma were screened for markers of inflammation (cell counts, tumor necrosis factor-? (TNF-?); macrophage inflammatory protein-2 (MIP-2); heme oxygenase-1 (HO-1); nuclear factor kappa-light-chain-enhancer of activated B cells p50 subunit (NF?B-p50); inducible nitric oxide synthetase (iNOS); endothelial-selectin (E-selectin)), cytotoxicity (lactate dehydrogenase (LDH); alkaline phosphatase (ALP); heat shock protein 70 (Hsp70); caspase-8-p18), and a putative pro-carcinogenic marker (cytochrome 1B1 (Cyp1B1)). Heart tissue was tested for HO-1, caspase-8-p18, NF?B-p50, iNOS, E-selectin, and myeloperoxidase (MPO); plasma was screened for markers of platelet activation and clot formation (soluble platelet-selectin (sP-selectin); fibrinogen; plasminogen activator inhibitor 1 (PAI-1)). PM1 triggers inflammation and cytotoxicity in lungs. A similar cytotoxic effect was observed on heart tissues, while plasma analyses suggest blood-endothelium interface activation. These data highlight the importance of lung inflammation in mediating adverse cardiovascular events following increase in ambient PM1 levels, providing evidences of a positive correlation between PM1 exposure and cardiovascular morbidity. PMID:23509745

  17. Arterial hypertension and cardiovascular prognosis after successful repair of aortic coarctation: a clinical model for the study of vascular function.

    PubMed

    de Divitiis, Marcello; Rubba, Paolo; Calabrò, Raffaele

    2005-10-01

    Despite successful surgical repair, aortic coarctation is associated with unfavourable prognosis mainly due to cardiovascular disease. Late timing of repair and arterial hypertension represent adverse prognostic factors. Arterial hypertension can recur after coarctation repair, despite the absence of residual obstruction, with a prevalence of up to 45%. Furthermore, even subjects with normal blood pressure values at rest may show an abnormal blood pressure elevation during exercise and daily life activities. The pathophysiology of such abnormal blood pressure behaviour is unclear. Different mechanisms have been proposed: resetting of the renin-angiotensin system, neurological dysfunction and impaired vascular reactivity and/or elastic properties. Several studies have supported these hypotheses, although the suggestion of a causative role of vascular dysfunction persisting late after coarctation repair has recently become more popular. Further studies are needed to investigate this issue; this particular syndrome may represent an important study model for the understanding of systolic hypertension. PMID:16216725

  18. Endothelin receptor polymorphisms in the cardiovascular system: potential implications for therapy and screening.

    PubMed

    Holzhauser, Luise; Zolty, Ronald

    2014-11-01

    Since its discovery in 1988, the endothelin system has been employed in multiple physiological and pathological roles. Endothelin-1 (ET-1) is not only a major regulator of vascular tone and cardiac contractility but also exerts mitogenic effects and is involved in inflammatory responses. ET-1 acts via two endothelin receptors located mainly on smooth muscle and endothelial cells through complex intracellular pathways differing between receptors and cell types. Polymorphisms of the endothelin receptor A have been associated not only with the risk in pulmonary arterial hypertension (PAH), systolic heart failure and systemic hypertension but are also of prognostic significance in dilated cardiomyopathy. Polymorphisms of endothelin receptors might lead to altered endothelin signaling and influence the response to endothelin receptor antagonist therapy in PAH in light of pharmacogenetics. This review will summarize the role of ET-1 within major cardiovascular pathologies and discuss endothelin receptor polymorphisms with special emphasis on potential therapeutic and screening implications. PMID:24570333

  19. The effect of blood volume loss on cardiovascular response to lower body negative pressure using a mathematical model

    NASA Technical Reports Server (NTRS)

    Karam, E. H.; Srinivasan, R. S.; Charles, J. B.; Fortney, S. M.

    1994-01-01

    Different mathematical models of varying complexity have been proposed in recent years to study the cardiovascular (CV) system. However, only a few of them specifically address the response to lower body negative pressure (LBNP), a stress that can be applied in weightlessness to predict changes in orthostatic tolerance. Also, the simulated results produced by these models agree only partially with experimental observations. In contrast, the model proposed by Melchior et al., and modified by Karam et al. is a simple representation of the CV system capable of accurately reproducing observed LBNP responses up to presyncopal levels. There are significant changes in LBNP response due to a loss of blood volume and other alterations that occur in weightlessness and related one-g conditions such as bedrest. A few days of bedrest can cause up to 15% blood volume loss (BVL), with consequent decreases in both stroke volume and cardiac output, and increases in heart rate, mean arterial pressure, and total peripheral resistance. These changes are more pronounced at higher levels of LBNP. This paper presents the results of a simulation study using our CV model to examine the effect of BVL on LBNP response.

  20. Results of a Markov model analysis to assess the cost-effectiveness of statin therapy for the primary prevention of cardiovascular disease in Korea: The Korean Individual-Microsimulation Model for Cardiovascular Health Interventions

    Microsoft Academic Search

    Hye-Young Kang; Su-Kyoung Ko; Danny Liew

    2009-01-01

    Background: Although hyperlipidemia is well recognized as a risk factor for cardiovascular disease (CVD), there has been no appraisal of the economic impact of statin therapy in Korea.Objective: The aim of this model analysis was to determine the cost-effectiveness of statin therapy versus no treatment for the primary prevention of CVD over a lifetime in Korea, from a health care

  1. Roles of the Chemokine System in Development of Obesity, Insulin Resistance, and Cardiovascular Disease

    PubMed Central

    Yao, Longbiao; Herlea-Pana, Oana; Heuser-Baker, Janet; Chen, Yitong; Barlic-Dicen, Jana

    2014-01-01

    The escalating epidemic of obesity has increased the incidence of obesity-induced complications to historically high levels. Adipose tissue is a dynamic energy depot, which stores energy and mobilizes it during nutrient deficiency. Excess nutrient intake resulting in adipose tissue expansion triggers lipid release and aberrant adipokine, cytokine and chemokine production, and signaling that ultimately lead to adipose tissue inflammation, a hallmark of obesity. This low-grade chronic inflammation is thought to link obesity to insulin resistance and the associated comorbidities of metabolic syndrome such as dyslipidemia and hypertension, which increase risk of type 2 diabetes and cardiovascular disease. In this review, we focus on and discuss members of the chemokine system for which there is clear evidence of participation in the development of obesity and obesity-induced pathologies. PMID:24741577

  2. Tenascin-C and mechanotransduction in the development and diseases of cardiovascular system

    PubMed Central

    Imanaka-Yoshida, Kyoko; Aoki, Hiroki

    2014-01-01

    Living tissue is composed of cells and extracellular matrix (ECM). In the heart and blood vessels, which are constantly subjected to mechanical stress, ECM molecules form well-developed fibrous frameworks to maintain tissue structure. ECM is also important for biological signaling, which influences various cellular functions in embryonic development, and physiological/pathological responses to extrinsic stimuli. Among ECM molecules, increased attention has been focused on matricellular proteins. Matricellular proteins are a growing group of non-structural ECM proteins highly up-regulated at active tissue remodeling, serving as biological mediators. Tenascin-C (TNC) is a typical matricellular protein, which is highly expressed during embryonic development, wound healing, inflammation, and cancer invasion. The expression is tightly regulated, dependent on the microenvironment, including various growth factors, cytokines, and mechanical stress. In the heart, TNC appears in a spatiotemporal-restricted manner during early stages of development, sparsely detected in normal adults, but transiently re-expressed at restricted sites associated with tissue injury and inflammation. Similarly, in the vascular system, TNC is strongly up-regulated during embryonic development and under pathological conditions with an increase in hemodynamic stress. Despite its intriguing expression pattern, cardiovascular system develops normally in TNC knockout mice. However, deletion of TNC causes acute aortic dissection (AAD) under strong mechanical and humoral stress. Accumulating reports suggest that TNC may modulate the inflammatory response and contribute to elasticity of the tissue, so that it may protect cardiovascular tissue from destructive stress responses. TNC may be a key molecule to control cellular activity during development, adaptation, or pathological tissue remodeling. PMID:25120494

  3. A cardiovascular disease policy model that predicts life expectancy taking into account socioeconomic deprivation

    PubMed Central

    Lewsey, J D; Lawson, K D; Ford, I; Fox, K A A; Ritchie, L D; Tunstall-Pedoe, H; Watt, G C M; Woodward, M; Kent, S; Neilson, M; Briggs, A H

    2015-01-01

    Objectives A policy model is a model that can evaluate the effectiveness and cost-effectiveness of interventions and inform policy decisions. In this study, we introduce a cardiovascular disease (CVD) policy model which can be used to model remaining life expectancy including a measure of socioeconomic deprivation as an independent risk factor for CVD. Design A state transition model was developed using the Scottish Heart Health Extended Cohort (SHHEC) linked to Scottish morbidity and death records. Individuals start in a CVD-free state and can transit to three CVD event states plus a non-CVD death state. Individuals who have a non-fatal first event are then followed up until death. Taking a competing risk approach, the cause-specific hazards of a first event are modelled using parametric survival analysis. Survival following a first non-fatal event is also modelled parametrically. We assessed discrimination, validation and calibration of our model. Results Our model achieved a good level of discrimination in each component (c-statistics for men (women)—non-fatal coronary heart disease (CHD): 0.70 (0.74), non-fatal cerebrovascular disease (CBVD): 0.73 (0.76), fatal CVD: 0.77 (0.80), fatal non-CVD: 0.74 (0.72), survival after non-fatal CHD: 0.68 (0.67) and survival after non-fatal CBVD: 0.65 (0.66)). In general, our model predictions were comparable with observed event rates for a Scottish randomised statin trial population which has an overlapping follow-up period with SHHEC. After applying a calibration factor, our predictions of life expectancy closely match those published in recent national life tables. Conclusions Our model can be used to estimate the impact of primary prevention interventions on life expectancy and can assess the impact of interventions on inequalities. PMID:25324535

  4. The degeneration of biological cardiovascular prostheses under pro-calcific metabolic conditions in a small animal model.

    PubMed

    Assmann, Alexander; Zwirnmann, Kai; Heidelberg, Friederike; Schiffer, Franziska; Horstkötter, Kim; Munakata, Hiroshi; Gremse, Felix; Barth, Mareike; Lichtenberg, Artur; Akhyari, Payam

    2014-08-01

    In order to allow for a comparative evaluation of the in vivo degeneration of biological and tissue-engineered heart valves and vascular grafts, a small animal model of accelerated cardiovascular calcification is desired. Wistar rats (n = 102; 6 groups) were fed ad libitum with regular chow and 5 different regimens of pro-calcific diet supplemented with combinations of vitamin D (VD), cholesterol (CH) and dicalcium phosphate (PH). Moreover, cryopreserved (n = 7) or detergent-decellularized rat aortic conduit grafts (n = 6) were infrarenally implanted in Wistar rats under severely pro-calcific conditions. The follow-up lasted up to 12 weeks. High-dose application of VD (300,000 IU/kg), CH (2%) and PH (1.5%) resulted in elevated serum calcium and cholesterol levels as well as LDL/HDL ratio. It increased the tissue MMP activity visualized by in situ zymography and caused significantly aggravated calcification of the native aortic valve as well as the aortic wall as assessed by histology and micro-computed tomography. (Immuno)histology and quantitative real-time PCR revealed chondro-osteogenic cell transformation, lipid deposition, nitrosative stress and low-level inflammation to be involved in the formation of calcific lesions. Despite pro-calcific in vivo conditions, decellularization significantly reduced calcification, inflammation and intimal hyperplasia in aortic conduit implants. A well balanced dietary trigger for pathologic metabolic conditions may represent an appropriate mid-term treatment to induce calcifying degeneration of aortic valves as well as vascular structures in the systemic circulation in rats. With respect to experimental investigation focusing on calcifying degeneration of native or prosthetic tissue, this regimen may serve as a valuable tool with a rapid onset and multi-facetted character of cardiovascular degeneration. PMID:24917029

  5. Implementation of the chronic care model in small medical practices improves cardiovascular risk but not glycemic control.

    PubMed

    Frei, Anja; Senn, Oliver; Chmiel, Corinne; Reissner, Josiane; Held, Ulrike; Rosemann, Thomas

    2014-04-01

    OBJECTIVE To test whether the implementation of elements of the Chronic Care Model (CCM) via a specially trained practice nurse leads to an improved cardiovascular risk profile among type 2 diabetes patients. RESEARCH DESIGN AND METHODS This cluster randomized controlled trial with primary care physicians as the unit of randomization was conducted in the German part of Switzerland. Three hundred twenty-six type 2 diabetes patients (age >18 years; at least one glycosylated hemoglobin [HbA1c] level of ?7.0% [53 mmol/mol] in the preceding year) from 30 primary care practices participated. The intervention included implementation of CCM elements and involvement of practice nurses in the care of type 2 diabetes patients. Primary outcome was HbA1c levels. The secondary outcomes were blood pressure (BP), LDL cholesterol, accordance with CCM (assessed by Patient Assessment of Chronic Illness Care [PACIC] questionnaire), and quality of life (assessed by the 36-item short-form health survey [SF-36]). RESULTS After 1 year, HbA1c levels decreased significantly in both groups with no significant difference between groups (-0.05% [-0.60 mmol/mol]; P = 0.708). Among intervention group patients, systolic BP (-3.63; P = 0.050), diastolic BP (-4.01; P < 0.001), LDL cholesterol (-0.21; P = 0.033), and PACIC subscores (P < 0.001 to 0.048) significantly improved compared with control group patients. No differences between groups were shown in the SF-36 subscales. CONCLUSIONS A chronic care approach according to the CCM and involving practice nurses in diabetes care improved the cardiovascular risk profile and is experienced by patients as a better structured care. Our study showed that care according to the CCM can be implemented even in small primary care practices, which still represent the usual structure in most European health care systems. PMID:24513589

  6. A System-Level Investigation into the Mechanisms of Chinese Traditional Medicine: Compound Danshen Formula for Cardiovascular Disease Treatment

    PubMed Central

    Li, Xiuxiu; Xu, Xue; Wang, Jinan; Yu, Hua; Wang, Xia; Yang, Hongjun; Xu, Haiyu; Tang, Shihuan; Li, Yan; Yang, Ling; Huang, Luqi; Wang, Yonghua; Yang, Shengli

    2012-01-01

    Compound Danshen Formula (CDF) is a widely used Traditional Chinese Medicine (TCM) which has been extensively applied in clinical treatment of cardiovascular diseases (CVDs). However, the underlying mechanism of clinical administrating CDF on CVDs is not clear. In this study, the pharmacological effect of CDF on CVDs was analyzed at a systemic point of view. A systems-pharmacological model based on chemical, chemogenomics and pharmacological data is developed via network reconstruction approach. By using this model, we performed a high-throughput in silico screen and obtained a group of compounds from CDF which possess desirable pharmacodynamical and pharmacological characteristics. These compounds and the corresponding protein targets are further used to search against biological databases, such as the compound-target associations, compound-pathway connections and disease-target interactions for reconstructing the biologically meaningful networks for a TCM formula. This study not only made a contribution to a better understanding of the mechanisms of CDF, but also proposed a strategy to develop novel TCM candidates at a network pharmacology level. PMID:22962593

  7. Marine and soil derived natural products: a new source of novel cardiovascular protective agents targeting the endothelin system.

    PubMed

    Planes, Nadir; Caballero-George, Catherina

    2015-06-01

    Inhibition of the endothelin system is a recognized therapeutic approach for treating complex cardiovascular diseases. The search for natural inhibitors of the endothelin system has focused mainly on land, with recent, emerging data suggesting the underestimated potential of marine microorganisms for producing leads with cardioprotective potential. The present work reviews natural products identified as inhibitors of the endothelin system, their origin, their mechanism of action, and their ecological significance. PMID:25654407

  8. Developing an Implementation through a Modeling of the Database for Cardiovascular Monitoring

    Microsoft Academic Search

    Hugo Bulegon; Silvio Bortoleto; Angelmar Constantino Roman

    2009-01-01

    The cardiovascular diseases are the most responsible for the deaths among adults in most of the world. Facilitate the clinical management in primary health care is essential to improve efficiency and to reduce morbidity and mortality. This article describes about a software focused on the management of major cardiovascular risk factors - CRF (diabetes, hypertension, dyslipidemia, smoking and others). After

  9. Polyphenols: Benefits to the Cardiovascular System in Health and in Aging

    PubMed Central

    Khurana, Sandhya; Venkataraman, Krishnan; Hollingsworth, Amanda; Piche, Matthew; Tai, T. C.

    2013-01-01

    Numerous studies have demonstrated the importance of naturally occurring dietary polyphenols in promoting cardiovascular health and emphasized the significant role these compounds play in limiting the effects of cellular aging. Polyphenols such as resveratrol, epigallocatechin gallate (EGCG), and curcumin have been acknowledged for having beneficial effects on cardiovascular health, while some have also been shown to be protective in aging. This review highlights the literature surrounding this topic on the prominently studied and documented polyphenols as pertaining to cardiovascular health and aging. PMID:24077237

  10. Targeted versus universal prevention. a resource allocation model to prioritize cardiovascular prevention

    PubMed Central

    2011-01-01

    Background Diabetes mellitus brings an increased risk for cardiovascular complications and patients profit from prevention. This prevention also suits the general population. The question arises what is a better strategy: target the general population or diabetes patients. Methods A mathematical programming model was developed to calculate optimal allocations for the Dutch population of the following interventions: smoking cessation support, diet and exercise to reduce overweight, statins, and medication to reduce blood pressure. Outcomes were total lifetime health care costs and QALYs. Budget sizes were varied and the division of resources between the general population and diabetes patients was assessed. Results Full implementation of all interventions resulted in a gain of 560,000 QALY at a cost of €640 per capita, about €12,900 per QALY on average. The large majority of these QALY gains could be obtained at incremental costs below €20,000 per QALY. Low or high budgets (below €9 or above €100 per capita) were predominantly spent in the general population. Moderate budgets were mostly spent in diabetes patients. Conclusions Major health gains can be realized efficiently by offering prevention to both the general and the diabetic population. However, a priori setting a specific distribution of resources is suboptimal. Resource allocation models allow accounting for capacity constraints and program size in addition to efficiency. PMID:21974836

  11. Pharmacogenomics and cardiovascular drugs: Need for integrated biological system with phenotypes and proteomic markers

    Microsoft Academic Search

    Gérard Siest; Jean-Brice Marteau; Sandy Maumus; Hind Berrahmoune; Elise Jeannesson; Anastasia Samara; Anne-Marie Batt; Sophie Visvikis-Siest

    2005-01-01

    Personalized medicine is based on a better knowledge of biological variability, considering the important part due to genetics. When trying to identify involved genes and their products in differential cardiovascular drug responses, a five-step strategy is to be followed:(1)Pharmacokinetic-related genes and phenotypes(2)Pharmacodynamic targets, genes and products(3)Cardiovascular diseases and risks depending on specific or large metabolic cycles(4)Physiological variations of previously identified

  12. Image-based computational fluid dynamics in blood vessel models: toward developing a prognostic tool to assess cardiovascular function changes in prolonged space flights

    NASA Astrophysics Data System (ADS)

    Chatzimavroudis, George P.; Spirka, Thomas A.; Setser, Randolph M.; Myers, Jerry G.

    2005-04-01

    One of NASA"s objectives is to be able to perform a complete pre-flight evaluation of possible cardiovascular changes in astronauts scheduled for prolonged space missions. Blood flow is an important component of cardiovascular function. Lately, attention has focused on using computational fluid dynamics (CFD) to analyze flow with realistic vessel geometries. MRI can provide detailed geometrical information and is the only clinical technique to measure all three spatial velocity components. The objective of this study was to investigate the reliability of MRI-based model reconstruction for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction using different resolution settings. The vessel walls were identified and the geometry was reconstructed using existing software. The geometry was then imported into a commercial CFD package for meshing and numerical solution. MRI velocity acquisitions provided true inlet boundary conditions for steady flow, as well as three-directional velocity data at several locations. In addition, an idealized version of each geometry was created from the model drawings. Contour and vector plots of the velocity showed identical features between the MRI velocity data, the MRI-based CFD data, and the idealized-geometry CFD data, with mean differences <10%. CFD results from different MRI resolution settings did not show significant differences (<5%). This study showed quantitatively that reliable CFD simulations can be performed in models reconstructed from MRI acquisitions and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system is possible.

  13. Evaluation of the Educational Value of YouTube Videos About Physical Examination of the Cardiovascular and Respiratory Systems

    PubMed Central

    2013-01-01

    Background A number of studies have evaluated the educational contents of videos on YouTube. However, little analysis has been done on videos about physical examination. Objective This study aimed to analyze YouTube videos about physical examination of the cardiovascular and respiratory systems. It was hypothesized that the educational standards of videos on YouTube would vary significantly. Methods During the period from November 2, 2011 to December 2, 2011, YouTube was searched by three assessors for videos covering the clinical examination of the cardiovascular and respiratory systems. For each video, the following information was collected: title, authors, duration, number of viewers, and total number of days on YouTube. Using criteria comprising content, technical authority, and pedagogy parameters, videos were rated independently by three assessors and grouped into educationally useful and non-useful videos. Results A total of 1920 videos were screened. Only relevant videos covering the examination of adults in the English language were identified (n=56). Of these, 20 were found to be relevant to cardiovascular examinations and 36 to respiratory examinations. Further analysis revealed that 9 provided useful information on cardiovascular examinations and 7 on respiratory examinations: scoring mean 14.9 (SD 0.33) and mean 15.0 (SD 0.00), respectively. The other videos, 11 covering cardiovascular and 29 on respiratory examinations, were not useful educationally, scoring mean 11.1 (SD 1.08) and mean 11.2 (SD 1.29), respectively. The differences between these two categories were significant (P<.001 for both body systems). The concordance between the assessors on applying the criteria was 0.89, with a kappa score >.86. Conclusions A small number of videos about physical examination of the cardiovascular and respiratory systems were identified as educationally useful; these videos can be used by medical students for independent learning and by clinical teachers as learning resources. The scoring system utilized by this study is simple, easy to apply, and could be used by other researchers on similar topics. PMID:24225171

  14. Dietary Maillard reaction products and their fermented products reduce cardiovascular risk in an animal model.

    PubMed

    Oh, N S; Park, M R; Lee, K W; Kim, S H; Kim, Y

    2015-08-01

    This study examined the effects of Maillard reaction products (MRP) and MRP fermented by lactic acid bacteria on antioxidants and their enhancement of cardiovascular health in ICR mouse and rat models. In previous in vitro studies, the selected lactic acid bacteria were shown to significantly affect the activity of MRP. The expression of genes (e.g., superoxide dismutase, catalase, and glutathione peroxidase) related to antioxidant activity was upregulated by Maillard-reacted sodium caseinate (cMRP), and cMRP fermented by Lactobacillus fermentum H9 (F-cMRP) synergistically increased the expression of catalase and superoxide dismutase when compared with the high-cholesterol-diet group. Bleeding time, the assay for determination of antithrombotic activity, was significantly prolonged by Maillard-reacted whey protein concentration (wMRP) and wMRP fermented by Lactobacillus gasseri H10 (F-wMRP), similar to the bleeding time of the aspirin group (positive control). In addition, the acute pulmonary thromboembolism-induced mice overcame severe body paralysis or death in both the wMRP and the F-wMRP groups. In the serum-level experiment, cMRP and F-cMRP significantly reduced the serum total and low-density lipoprotein cholesterol levels and triglycerides but had only a slight effect on high-density lipoprotein cholesterol. The levels of aspartate transaminase and alanine transaminase also declined in the cMRP and F-cMRP intake groups compared with the high-cholesterol-diet group. In particular, F-cMRP showed the highest reducing effects on triglycerides, aspartate transaminase, and alanine transaminase. Moreover, the expression of cholesterol-related genes in the F-cMRP group demonstrated greater effects than for the cMRP group in the level of cholesterol 7 ?-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), and low-density lipoprotein receptors compared with the high-cholesterol-diet group. The protective role of cMRP and F-cMRP in the high-cholesterol group may have been the result of an antioxidative defense mechanism that regulated cholesterol synthesis and metabolism. Therefore, F-cMRP and cMRP have the potential to play preventive and therapeutic roles in the management of cardiovascular disease. PMID:26004833

  15. Using an Informal Cardiovascular System Activity to Study the Effectiveness of Science Education in Unexpected Places

    NASA Astrophysics Data System (ADS)

    Monzack, Elyssa Lynne; Petersen, Greta M. Zenner

    2011-08-01

    Venues for informal science education are usually those sought out by people who are specifically looking for an educational experience. Whether planning a trip to a museum or choosing a television program, these individuals are actively seeking an informal educational experience; they are a self-selected group. This paper investigates whether members of the public will respond to an informal science activity that is placed in a location where learning about science would be unexpected. This project developed and used an activity about the cardiovascular system in which participants were able to walk the path of blood flow through the heart, body, and lungs. This activity was tested in two types of settings: where science was either expected or unexpected. A non-traditional assessment method was used to evaluate the effectiveness of the activity in the unexpected versus the expected settings. Ultimately, the activity was found to be equally effective in both settings, providing evidence for success in bringing informal science education to the general population in non-traditional venues.

  16. [Biological role of Interleukin 33 and its importance in pathophysiology of cardiovascular system].

    PubMed

    Czyzewska-Buczy?ska, Agnieszka; Zuk, Natalia; Romanowska-Micherda, Katarzyna; Witkiewicz, Wojciech

    2014-01-01

    Interleukin 33 (IL-33) is a member of the IL-1 cytokin family. It is expressed by various cells and tissues, mainly epithelial and endothelial cells. It is a cytokine with dual function. It may act both as a traditional cytokine and as intracellular nuclear factor, functioning as transcription regulator. Its biological effect via interaction with membrane-bound ST2 receptor and IL-1 receptor accessory protein (IL-1RAcP) is associated with the induction of Th2-type immune response and IL-5 and IL-13 synthesis. IL-33 has a strong immunoregulatory properties. Depending on the type of activated cells, microenvironment, and costimulatory factors, IL-33 can act either as a pro- or anti-inflammatory cytokine. Recent studies indicate various protective effect of IL-33/ST2 sygnaling in atherosclerosis, obesity, disorders in glucose homeostasis and in heart diseases. The paper presents current state of knowledge about the structure and biological function of IL-33 and its receptor ST2, with particular emphasis on its role in pathophysiology of cardiovascular system. PMID:24988604

  17. Cardiovascular and organ responses and adaptation responses to hypogravity in an experimental animal model.

    NASA Astrophysics Data System (ADS)

    Biondi, R.; Capodicasa, E.; Tassi, C.; Mezzasomal, L.; Benedetti, C.; Valiani, M.; Marconi, P.; Rossi, R.

    1995-10-01

    The head-down suspension (i.e antiorthostatic hypokinesia) rat is used to simulate weightlessness. However, little is known about cardiovascular and organ adaptation responses which, over a long time, can become pathologically significant. The purpose of this study was therefore to evaluate regional changes in the hematology parameters, Endotheline-1 (ET-1) concentration and urinary excretion of N-acetyl-?-D-glucosaminidase (EC 3.2.1.30) (NAG) in an experimental antiorthostatic rat model. The data indicate significant variations in the plasma ET-1 level in time, in the superior and inferior cava vessel blood of animals maintained for 10 days in hypogravity with respect to controls. These changes do not seem to be due to hemoconcentration. The increase in urinary NAG was observed during the first 24h of experiment, indicating renal stress, probably due to adverse blood flow variations within the organ. We conclude that the plasma ET-1 level changes could be responsible, overall for the blood flow variations in the kidney and renal stress could be the consequence of extended antiorthostatic hypokinesia. The ET-1 behaviour and urinary NAG excretion in rats exposed to antiorthostatic hypokjnetic hydynamia offer possibilities for understanding if these changes might be reversible or when they become pathological. This could give some relevant information about the effects of prolonged hypogravity during the space voyage.

  18. Asymmetric Dimethylarginine as a Surrogate Marker of Endothelial Dysfunction and Cardiovascular Risk in Patients with Systemic Rheumatic Diseases

    PubMed Central

    Dimitroulas, Theodoros; Sandoo, Aamer; Kitas, George D.

    2012-01-01

    The last few decades have witnessed an increased life expectancy of patients suffering with systemic rheumatic diseases, mainly due to improved management, advanced therapies and preventative measures. However, autoimmune disorders are associated with significantly enhanced cardiovascular morbidity and mortality not fully explained by traditional cardiovascular disease (CVD) risk factors. It has been suggested that interactions between high-grade systemic inflammation and the vasculature lead to endothelial dysfunction and atherosclerosis, which may account for the excess risk for CVD events in this population. Diminished nitric oxide synthesis—due to down regulation of endothelial nitric oxide synthase—appears to play a prominent role in the imbalance between vasoactive factors, the consequent impairment of the endothelial hemostasis and the early development of atherosclerosis. Asymmetric dimethylarginine (ADMA) is one of the most potent endogenous inhibitors of the three isoforms of nitric oxide synthase and it is a newly discovered risk factor in the setting of diseases associated with endothelial dysfunction and adverse cardiovascular events. In the context of systemic inflammatory disorders there is increasing evidence that ADMA contributes to the vascular changes and to endothelial cell abnormalities, as several studies have revealed derangement of nitric oxide/ADMA pathway in different disease subsets. In this article we discuss the role of endothelial dysfunction in patients with rheumatic diseases, with a specific focus on the nitric oxide/ADMA system and we provide an overview on the literature pertaining to ADMA as a surrogate marker of subclinical vascular disease. PMID:23202900

  19. Systemic inflammation and cardiovascular risk factors predict rapid progression of atherosclerosis in rheumatoid arthritis

    PubMed Central

    del Rincón, Inmaculada; Polak, Joseph F; O’Leary, Daniel H; Battafarano, Daniel F; Erikson, John M; Restrepo, Jose F; Molina, Emily; Escalante, Agustín

    2014-01-01

    Objective To estimate atherosclerosis progression and identify influencing factors in rheumatoid arthritis (RA). Methods We used carotid ultrasound to measure intima-media thickness (IMT) in RA patients, and ascertained cardiovascular (CV) risk factors, inflammation markers and medications. A second ultrasound was performed approximately 3 years later. We calculated the progression rate by subtracting the baseline from the follow-up IMT, divided by the time between the two scans. We used logistic regression to identify baseline factors predictive of rapid progression. We tested for interactions of erythrocyte sedimentation rate (ESR) with CV risk factors and medication use. Results Results were available for 487 RA patients. The mean (SD) common carotid IMT at baseline was 0.571 mm (0.151). After a mean of 2.8 years, the IMT increased by 0.050 mm (0.055), p?0.001, a progression rate of 0.018 mm/year (95% CI 0.016 to 0.020). Baseline factors associated with rapid progression included the number of CV risk factors (OR 1.27 per risk factor, 95% CI 1.01 to 1.61), and the ESR (OR 1.12 per 10 mm/h, 95% CI 1.02 to 1.23). The ESR×CV risk factor and ESR×medication product terms were significant, suggesting these variables modify the association between the ESR and IMT progression. Conclusions Systemic inflammation and CV risk factors were associated with rapid IMT progression. CV risk factors may modify the role of systemic inflammation in determining IMT progression over time. Methotrexate and antitumour necrosis factor agents may influence IMT progression by reducing the effect of the systemic inflammation on the IMT. PMID:24845391

  20. An isolated perfused pig heart model for the development, validation and translation of novel cardiovascular magnetic resonance techniques

    PubMed Central

    2010-01-01

    Background Novel cardiovascular magnetic resonance (CMR) techniques and imaging biomarkers are often validated in small animal models or empirically in patients. Direct translation of small animal CMR protocols to humans is rarely possible, while validation in humans is often difficult, slow and occasionally not possible due to ethical considerations. The aim of this study is to overcome these limitations by introducing an MR-compatible, free beating, blood-perfused, isolated pig heart model for the development of novel CMR methodology. Methods 6 hearts were perfused outside of the MR environment to establish preparation stability. Coronary perfusion pressure (CPP), coronary blood flow (CBF), left ventricular pressure (LVP), arterial blood gas and electrolyte composition were monitored over 4 hours. Further hearts were perfused within 3T (n = 3) and 1.5T (n = 3) clinical MR scanners, and characterised using functional (CINE), perfusion and late gadolinium enhancement (LGE) imaging. Perfusion imaging was performed globally and selectively for the right (RCA) and left coronary artery (LCA). In one heart the RCA perfusion territory was determined and compared to infarct size after coronary occlusion. Results All physiological parameters measured remained stable and within normal ranges. The model proved amenable to CMR at both field strengths using typical clinical acquisitions. There was good agreement between the RCA perfusion territory measured by selective first pass perfusion and LGE after coronary occlusion (37% versus 36% of the LV respectively). Conclusions This flexible model allows imaging of cardiac function in a controllable, beating, human-sized heart using clinical MR systems. It should aid further development, validation and clinical translation of novel CMR methodologies, and imaging sequences. PMID:20849589

  1. [Short-term adaptation of cardiovascular system of children of 5-7 years to mental loading].

    PubMed

    Sharapov, A N; Bezobrazova, V N; Zinenko, E S; Kmit', G V

    2010-01-01

    For the purpose of revealing of adaptable possibilities of cardiovascular system research of 150 children of 5-7 years by a method oftetrapolar reography on Kubichek at rest and at mental loading. Research has shown that from 5 to 7 years there are essential changes of parameters of central haemodynamics: increase systolic and diastolic arterial pressure (SAP and DAP), increase stroke volume (SV) and the minute blood volume (MBV), and as decrease heart rate (HR). Mental loading causes two variants of reaction of stroke volume. The first variant was characterized by increase SV, the second - decreaseb SVand increase DAP. Short-term Adaptation to mental loading at the majority of children of 5-7 years independently of and orientation of changes SVwas not accompanied by pressure of regulation's mechanisms of cardiovascular system and had favorable character. At 13-15% of all surveyed children short-term adaptation to mental loading was characterized by considerable pressure of regulation's mechanisms of cardiovascular system. It was expressed in increase the SAP, DAP, HR, GPVR, SPVR, decrease SVand MBV, and also the long period of reconstraction the majority of parameters of central haemodynamics. PMID:20586305

  2. A farnesyltransferase inhibitor prevents both the onset and late progression of cardiovascular disease in a progeria mouse model

    PubMed Central

    Capell, Brian C.; Olive, Michelle; Erdos, Michael R.; Cao, Kan; Faddah, Dina A.; Tavarez, Urraca L.; Conneely, Karen N.; Qu, Xuan; San, Hong; Ganesh, Santhi K.; Chen, Xiaoyan; Avallone, Hedwig; Kolodgie, Frank D.; Virmani, Renu; Nabel, Elizabeth G.; Collins, Francis S.

    2008-01-01

    Hutchinson-Gilford progeria syndrome (HGPS) is the most dramatic form of human premature aging. Death occurs at a mean age of 13 years, usually from heart attack or stroke. Almost all cases of HGPS are caused by a de novo point mutation in the lamin A (LMNA) gene that results in production of a mutant lamin A protein termed progerin. This protein is permanently modified by a lipid farnesyl group, and acts as a dominant negative, disrupting nuclear structure. Treatment with farnesyltransferase inhibitors (FTIs) has been shown to prevent and even reverse this nuclear abnormality in cultured HGPS fibroblasts. We have previously created a mouse model of HGPS that shows progressive loss of vascular smooth muscle cells in the media of the large arteries, in a pattern that is strikingly similar to the cardiovascular disease seen in patients with HGPS. Here we show that the dose-dependent administration of the FTI tipifarnib (R115777, Zarnestra) to this HGPS mouse model can significantly prevent both the onset of the cardiovascular phenotype as well as the late progression of existing cardiovascular disease. These observations provide encouraging evidence for the current clinical trial of FTIs for this rare and devastating disease. PMID:18838683

  3. Type I Interferons Are Associated with Subclinical Markers of Cardiovascular Disease in a Cohort of Systemic Lupus Erythematosus Patients

    PubMed Central

    Somers, Emily C.; Zhao, Wenpu; Lewis, Emily E.; Wang, Lu; Wing, Jeffrey J.; Sundaram, Baskaran; Kazerooni, Ella A.

    2012-01-01

    Background Systemic lupus erythematosus (SLE) patients have a striking increase in cardiovascular (CV) comorbidity not fully explained by the Framingham risk score. Recent evidence from in vitro studies suggests that type I interferons (IFN) could promote premature CV disease (CVD) in SLE. We assessed the association of type I IFN signatures with functional and anatomical evidence of vascular damage, and with biomarkers of CV risk in a cohort of lupus patients without overt CVD. Methodology/Principal Findings Serum type I IFN activity (induction of five IFN-inducible genes; IFIGs) from 95 SLE patient and 38 controls was quantified by real-time PCR. Flow mediated dilatation (FMD) of the brachial artery and carotid intima media thickness (CIMT) were quantified by ultrasound, and coronary calcification by computed tomography. Serum vascular biomarkers were measured by ELISA. We evaluated the effect of type I IFNs on FMD, CIMT and coronary calcification by first applying principal components analysis to combine data from five IFIGs into summary components that could be simultaneously modeled. Three components were derived explaining 97.1% of the total IFIG variation. Multivariable linear regression was utilized to investigate the association between the three components and other covariates, with the outcomes of FMD and CIMT; zero-inflated Poisson regression was used for modeling of coronary calcification. After controlling for traditional CV risk factors, enhanced serum IFN activity was significantly associated with decreased endothelial function in SLE patients and controls (p<0.05 for component 3), increased CIMT among SLE patients (p<0.01 for components 1 and 2), and severity of coronary calcification among SLE patients (p<0.001 for component 3). Conclusions Type I IFNs are independently associated with atherosclerosis development in lupus patients without history of overt CVD and after controlling for Framingham risk factors. This study further supports the hypothesis that type I IFNs promote premature vascular damage in SLE. PMID:22606325

  4. 78 FR 36702 - Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems (IABP) for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ...Counterpulsion in High Risk OPCAB Surgery: A Prospective Randomised...Journal of Cardiac Surgery, vol. 18, pp. 286...Balloon Pump in High-Risk Patients Undergoing Coronary...Cardiovascular and Thoracic Surgery, vol. 9, pp. 291-294...Federal Food, Drug, and Cosmetic Act and under...

  5. Pathophysiology of isoprostanes in the cardiovascular system: implications of isoprostane-mediated thromboxane A2 receptor activation

    PubMed Central

    Bauer, Jochen; Ripperger, Anne; Frantz, Stefan; Ergün, Süleyman; Schwedhelm, Edzard; Benndorf, Ralf A

    2014-01-01

    Isoprostanes are free radical-catalysed PG-like products of unsaturated fatty acids, such as arachidonic acid, which are widely recognized as reliable markers of systemic lipid peroxidation and oxidative stress in vivo. Moreover, activation of enzymes, such as COX-2, may contribute to isoprostane formation. Indeed, formation of isoprostanes is considerably increased in various diseases which have been linked to oxidative stress, such as cardiovascular disease (CVD), and may predict the atherosclerotic burden and the risk of cardiovascular complications in the latter patients. In addition, several isoprostanes may directly contribute to the functional consequences of oxidant stress via activation of the TxA2 prostanoid receptor (TP), for example, by affecting endothelial cell function and regeneration, vascular tone, haemostasis and ischaemia/reperfusion injury. In this context, experimental and clinical data suggest that selected isoprostanes may represent important alternative activators of the TP receptor when endogenous TxA2 levels are low, for example, in aspirin-treated individuals with CVD. In this review, we will summarize the current understanding of isoprostane formation, biochemistry and (patho) physiology in the cardiovascular context. PMID:24646155

  6. Influence of Air Pollution on Cardiovascular Diseases Prevalence in Developing Countries: An Eco-Social Model

    Microsoft Academic Search

    Lateef O. Olayanju; Raouf N. G. Naguib; Quynh T. Nguyen; Mohyi H. Shaker; Jerry S. Pantuvo

    2011-01-01

    Over the years, there has been increased concern about the apparent rise in the occurrence of Cardiovascular Diseases (CVDs), particularly in developing countries. Research conducted, mainly in developed countries, has suggested possible links between the occurrence of these diseases and air pollution exposures, different risk estimates that support policy making on air pollution regulation in these regions have also been

  7. Sheep (Ovis aries) as a Model for Cardiovascular Surgery and Management before, during, and after Cardiopulmonary Bypass

    PubMed Central

    DiVincenti, Louis; Westcott, Robin; Lee, Candice

    2014-01-01

    Because of its similarity to humans in important respects, sheep (Ovis aries) are a common animal model for translational research in cardiovascular surgery. However, some unique aspects of sheep anatomy and physiology present challenges to its use in these complicated experiments. In this review, we discuss relevant anatomy and physiology of sheep and discuss management before, during, and after procedures requiring cardiopulmonary bypass to provide a concise source of information for veterinarians, technicians, and researchers developing and implementing protocols with this model. PMID:25255065

  8. Long?Term Renal Denervation Normalizes Disrupted Blood Pressure Circadian Rhythm and Ameliorates Cardiovascular Injury in a Rat Model of Metabolic Syndrome

    PubMed Central

    Katayama, Tetsuji; Sueta, Daisuke; Kataoka, Keiichiro; Hasegawa, Yu; Koibuchi, Nobutaka; Toyama, Kensuke; Uekawa, Ken; MingJie, Ma; Nakagawa, Takashi; Maeda, Masanobu; Ogawa, Hisao; Kim?Mitsuyama, Shokei

    2013-01-01

    Background Although renal denervation significantly reduces blood pressure in patients with resistant hypertension, the role of the renal nerve in hypertension with metabolic syndrome is unknown. We investigated the impact of long?term renal denervation on SHR/NDmcr?cp(+/+) (SHRcp) rats, a useful rat model of metabolic syndrome, to determine the role of the renal nerve in hypertension with metabolic syndrome. Methods and Results SHRcp rats were divided into (1) a renal denervation (RD) group and (2) a sham operation group (control) to examine the effects of long?term RD on blood pressure circadian rhythm, renal sodium retention?related molecules, the renin?angiotensin?aldosterone system, metabolic disorders, and organ injury. RD in SHRcp rats not only significantly reduced blood pressure but also normalized blood pressure circadian rhythm from the nondipper to the dipper type, and this improvement was associated with an increase in urinary sodium excretion and the suppression of renal Na+?Cl? cotransporter upregulation. RD significantly reduced plasma renin activity. RD significantly prevented cardiovascular remodeling and impairment of vascular endothelial function and attenuated cardiovascular oxidative stress. However, RD failed to ameliorate obesity, metabolic disorders, and renal injury and failed to reduce systemic sympathetic activity in SHRcp rats. Conclusions By including the upregulation of the Na+?Cl? cotransporter, the renal sympathetic nerve is involved in the disruption of blood pressure circadian rhythm as well as hypertension in metabolic syndrome. Thus, RD seems to be a useful therapeutic strategy for hypertension with metabolic syndrome. PMID:23974905

  9. Challenges and opportunities in cardiovascular health informatics.

    PubMed

    Zhang, Yuan-Ting; Zheng, Ya-Li; Lin, Wan-Hua; Zhang, He-Ye; Zhou, Xiao-Lin

    2013-03-01

    Cardiovascular health informatics is a rapidly evolving interdisciplinary field concerning the processing, integration/interpretation, storage, transmission, acquisition, and retrieval of information from cardiovascular systems for the early detection, early prediction, early prevention, early diagnosis, and early treatment of cardiovascular diseases (CVDs). Based on the first author's presentation at the first IEEE Life Sciences Grand Challenges Conference, held on October 4-5, 2012, at the National Academy of Sciences, Washington, DC, USA, this paper, focusing on coronary arteriosclerotic disease, will discuss three significant challenges of cardiovascular health informatics, including: 1) to invent unobtrusive and wearable multiparameter sensors with higher sensitivity for the real-time monitoring of physiological states; 2) to develop fast multimodal imaging technologies with higher resolution for the quantification and better understanding of structure, function, metabolism of cardiovascular systems at the different levels; and 3) to develop novel multiscale information fusion models and strategies with higher accuracy for the personalized predication of the CVDs. At the end of this paper, a summary is given to suggest open discussions on these three and more challenges that face the scientific community in this field in the future. PMID:23380853

  10. Introducing a model of cardiovascular prevention in Nairobi's slums by integrating a public health and private-sector approach: the SCALE-UP study

    PubMed Central

    van de Vijver, Steven; Oti, Samuel; Tervaert, Thijs Cohen; Hankins, Catherine; Kyobutungi, Catherine; Gomez, Gabriela B.; Brewster, Lizzy; Agyemang, Charles; Lange, Joep

    2013-01-01

    Introduction Cardiovascular disease (CVD) is a leading cause of death in sub-Saharan Africa (SSA), with annual deaths expected to increase to 2 million by 2030. Currently, most national health systems in SSA are not adequately prepared for this epidemic. This is especially so in slum settlements where access to formal healthcare and resources is limited. Objective To develop and introduce a model of cardiovascular prevention in the slums of Nairobi by integrating public health and private sector approaches. Study design Two non-profit organizations that conduct public health research, Amsterdam Institute for Global Health and Development (AIGHD) and African Population and Health Research Center (APHRC), collaborated with private-sector Boston Consulting Group (BCG) to develop a service delivery package for CVD prevention in slum settings. A theoretic model was designed based on the integration of public and private sector approaches with the focus on costs and feasibility. Results The final model includes components that aim to improve community awareness, a home-based screening service, patient and provider incentives to seek and deliver treatment specifically for hypertension, and adherence support. The expected outcomes projected by this model could prove potentially cost effective and affordable (1 USD/person/year). The model is currently being implemented in a Nairobi slum and is closely followed by key stakeholders in Kenya including the Ministry of Health, the World Health Organization (WHO), and leading non-governmental organizations (NGOs). Conclusion Through the collaboration of public health and private sectors, a theoretically cost-effective model was developed for the prevention of CVD and is currently being implemented in the slums of Nairobi. If results are in line with the theoretical projections and first impressions on the ground, scale-up of the service delivery package could be planned in other poor urban areas in Kenya by relevant policymakers and NGOs. PMID:24149078

  11. Vanadate as factor of cardiovascular regulation by interactions with the catecholamine and nitric oxide systems

    Microsoft Academic Search

    Marco Carmignani; Anna Rita Volpe; Oliviero Masci; Paolo Boscolo; Franco Di Giacomo; Alfredo Grilli; Goffredo del Rosso; Mario Felaco

    1996-01-01

    The effects of 1 ?g\\/ mL of vanadium, given for 12 mo as sodium metavanadate in drinking water, on cardiovascular and biochemical\\u000a indices of male rabbits were investigated. At the end of the exposure period, vanadium was more accumulated in bones and kidneys\\u000a than in spleen and liver; the cardiac ventricles and the aorta contained similar amounts of this element.

  12. From form to function: the role of Nox4 in the cardiovascular system

    PubMed Central

    Chen, Feng; Haigh, Stephen; Barman, Scott; Fulton, David J. R.

    2012-01-01

    The NADPH oxidase (Nox) family of proteins is comprised of seven members, including Noxes1–5 and the Duoxes 1 and 2. Nox4 is readily distinguished from the other Nox isoforms by its high level of expression in cardiovascular tissues and unique enzymatic properties. Nox4 is constitutively active and the amount of reactive oxygen species (ROS) contributed by Nox4 is primarily regulated at the transcriptional level although there is recent evidence for post-translational control. Nox4 emits a different pattern of ROS and its subcellular localizations, tissue distribution and influence over signaling pathways is different from the other Nox enzymes. Previous investigations have revealed that Nox4 is involved in oxygen sensing, vasomotor control, cellular proliferation, differentiation, migration, apoptosis, senescence, fibrosis, and angiogenesis. Elevated expression of Nox4 has been reported in a number of cardiovascular diseases, including atherosclerosis, pulmonary fibrosis, and hypertension, cardiac failure and ischemic stroke. However, many important questions remain regarding the functional significance of Nox4 in health and disease, including the role of Nox4 subcellular localization and its downstream targets. The goal of this review is to summarize the recent literature on the genetic and enzymatic regulation, subcellular localization, signaling pathways, and the role of Nox4 in cardiovascular disease states. PMID:23125837

  13. MicroRNAs and Cardiovascular Diseases

    PubMed Central

    Ono, Koh; Kuwabara, Yasuhide; Han, Jiahuai

    2011-01-01

    MicroRNAs (miRNAs) are a class of small noncoding RNAs that have gained status as important regulators of gene expression. Recent studies have demonstrated that miRNAs are aberrantly expressed in the cardiovascular system under some pathological conditions. Gain- and loss-of-function studies using in vitro and in vivo models have revealed distinct roles for specific miRNAs in cardiovascular development and physiological function. The implications of miRNAs in cardiovascular disease have recently been recognized, representing the most rapidly evolving research field. In the present article, the currently relevant findings on the role of miRNAs in cardiac diseases will be updated and the target genes of these miRNAs are summarized. PMID:21395978

  14. NADPH oxidases in cardiovascular disease: insights from in vivo models and clinical studies

    Microsoft Academic Search

    Alexander Sirker; Min Zhang; Ajay M. Shah

    NADPH oxidase family enzymes (or NOXs) are the major sources of reactive oxygen species (ROS) that are implicated in the pathophysiology\\u000a of many cardiovascular diseases. These enzymes appear to be especially important in the modulation of redox-sensitive signalling\\u000a pathways that underlie key cellular functions such as growth, differentiation, migration and proliferation. Seven distinct\\u000a members of the family have been identified

  15. Taurine Supplementation Reduces Oxidative Stress and Improves Cardiovascular Function in an Iron-Overload Murine Model

    Microsoft Academic Search

    Gavin Y. Oudit; Maria G. Trivieri; Neelam Khaper; Taneya Husain; Greg J. Wilson; Peter Liu; Michael J. Sole; Peter H. Backx

    2010-01-01

    Background—Iron overload has an increasing worldwide prevalence and is associated with significant cardiovascular morbidity and mortality. Elevated iron levels in the myocardium lead to impaired systolic and diastolic function and elevated oxidative stress. Taurine accounts for 25% to 50% of the amino acid pool in myocardium, possesses antioxidant properties, and can inhibit L-type Ca2 channels. Thus, we hypothesized that this

  16. Laser Doppler flowmetry signals to quantify effects of isoflurane on the peripheral cardiovascular system of healthy rats

    NASA Astrophysics Data System (ADS)

    Humeau, Anne; Fizanne, Lionel; Roux, Jérôme; Asfar, Pierre; Cales, Paul; Rousseau, David; Chapeau-Blondeau, François

    2007-12-01

    The optical Doppler effect resulting from interactions between laser light photons and red blood cells of the microcirculation is used to characterize the influence of isoflurane, an halogenated volatile anesthetic, on the peripheral cardiovascular system. After having recorded laser Doppler flowmetry blood perfusion signals on isoflurane-induced anesthetized healthy rats, wavelet analyses show a significant decrease of the myogenic and neurogenic activities when isoflurane dose increases from 1.5% to 3%. Moreover, the approximate entropy shows a weak decrease of signal irregularity when dose of isoflurane increases. These findings demonstrate the usefulness of the optical Doppler effect in physiological and pharmacological applications.

  17. Postdoctoral Fellow Neural Cardiovascular Physiology

    E-print Network

    Collett Jr., Jeffrey L.

    or ancestry, sex, gender, disability, veteran status, genetic information, sexual orientation, or genderPostdoctoral Fellow Neural Cardiovascular Physiology Job Description A postdoctoral position and physiological roles of new components of the renin-angiotensin system in the regulation of cardiovascular

  18. BE 508: Quantitative Studies of Respiratory and Cardiovascular Systems Spring Semester, 2013

    E-print Network

    Vajda, Sandor

    3. To introduce quantitative models of the cardio-pulmonary systems 4. To introduce instrumentation and measurement techniques for assessing cardio-pulmonary function Main Topics: 1. Basic anatomy and physiology) Laboratory: A comprehensive set of laboratory exercises will be given including the following topics

  19. Mechanism of tissue-selective drug action in the cardiovascular system.

    PubMed

    Barrett, Terrance D; Triggle, David J; Walker, Michael J A; Maurice, Donald H

    2005-04-01

    Analysis of the human genome project tells us that there may be as few as 3000 genes that are likely to be good drug targets. Although the number of targets is still very large, these data have been interpreted by some to mean that the pharmaceutical industry may someday run out of novel drug targets. Despite the doom and gloom of such analysis, there is considerable reason for optimism. Drugs may exhibit selectivity of action beyond that predicted by target expression alone. Drugs that act at a single molecular target may have very different pharmacology and, as a result, different therapeutic uses. Three well-characterized model systems are highlighted to illustrate this point. The first model system is exemplified by nifedipine and verapamil, both of which act on L-type calcium channels. Both drugs are used to treat hypertension, but only verapamil can be used to produce atrioventricular block in patients with atrial fibrillation. The second model system describes the therapeutic exploitation of unusual conditions that occur in the ischemic myocardium to produce drugs that are more effective for suppressing ischemia-induced arrhythmias. The third model system discusses the mechanisms through which phosphodiesterase-5 (PDE5) inhibitors act selectively to facilitate penile erection while having little effect in the non-penile vasculature that also expresses PDE5. PMID:15821157

  20. Periodontal disease in relation to selected parameters of the cardiovascular system in a group of patients with stable angina pectoris

    PubMed Central

    W?osowicz, Monika; Górska, Renata

    2014-01-01

    Introduction Periodontal diseases (PD), which are the cause of chronic inflammatory processes, can develop increased susceptibility to vascular diseases through atherosclerosis. Due to the raised inflammatory and thrombotic risk, PD can have a significant influence on the course and results of stable angina pectoris (SAP). Objectives The aim of the study is to evaluate the influence of chosen PD parameters on selected cardiovascular system parameters, and the correlation between chosen parameters of periodontitis and cardiovascular system parameters. Material and methods The case group included 67 patients with SAP, ? 60 years of age. The occurrence of well-known cardiovascular disease risk factors was evaluated on the basis of the clinical interview, clinical examination and laboratory tests. The occurrence of known risk factors for cardiovascular diseases (CVD) was established on the basis of the interview, clinical research and laboratory tests. Periodontal examination included API (approximal plaque index), CAL (clinical attachment level), PD (pocket depth), and BI (bleeding index). IMT (intima-media thickness) and the size of atherosclerotic plaque in carotid arteries were assessed by ultrasound examination. Segmental contractility abnormalities were assessed on the basis of echocardiography examination, presence of the single-vessel vascular and multi-vessel vascular disease on the basis of angiographic examination. Results In the study group of patients, numerous risk factors and a higher level of API, CAL, PD and BI were observed. A higher prevalence of multi-vessel disease (75%) than single-vessel disease (25%) was noted on the basis of angiographic examination. Patients with contractility abnormalities demonstrated also poor oral cavity health. In addition, a higher concentration of CRP (3.2 mg/dl), fibrinogen (3.3 g/l)) and the progression of atherosclerosis, e.g. increased IMT (2.1 mm) and formation of atherosclerotic plaques were noted. Results of multivariate logistic regression demonstrated that API and PD had a significant influence on IMT. In patients with BMI ? 30 kg/m2, the risk of increased IMT (OR = 4.67) was fourfold higher. Summary Periodontitis may influence the occurrence and course of the atherosclerotic process in persons with stable angina.

  1. Role of endotoxemia in cardiovascular dysfunction and mortality. Escherichia coli and Staphylococcus aureus challenges in a canine model of human septic shock.

    PubMed Central

    Natanson, C; Danner, R L; Elin, R J; Hosseini, J M; Peart, K W; Banks, S M; MacVittie, T J; Walker, R I; Parrillo, J E

    1989-01-01

    Using different types of bacteria and a canine model simulating human septic shock, we investigated the role of endotoxin in cardiovascular dysfunction and mortality. Either Escherichia coli (a microorganism with endotoxin) or Staphylococcus aureus (a microorganism without endotoxin) were placed in an intraperitoneal clot in doses of viable or formalin-killed bacteria. Cardiovascular function of conscious animals was studied using simultaneous radionuclide heart scans and thermodilution cardiac outputs. Serial plasma endotoxin levels were measured. S. aureus produced a pattern of reversible cardiovascular dysfunction over 7-10 d that was concordant (P less than 0.01) with that of E. coli. Although this cardiovascular pattern was not altered by formalin killing (S. aureus and E. coli), formalin-killed organisms produced a lower mortality and less myocardial depression (P less than 0.01). S. aureus, compared to E. coli, produced higher postmortem concentrations of microorganisms and higher mortality (P less than 0.025). E. coli produced significant endotoxemia (P less than 0.01), though viable organisms (versus nonviable) resulted in higher endotoxin blood concentrations (P less than 0.05). Significant endotoxemia did not occur with S. aureus. Thus, in the absence of endotoxemia, S. aureus induced the same cardiovascular abnormalities of septic shock as E. coli. These findings indicate that structurally and functionally distinct microorganisms, with or without endotoxin, can activate a common pathway resulting in similar cardiovascular injury and mortality. PMID:2642920

  2. Should non-cardiovascular mortality be considered in the SCORE model? Findings from the Prevention of Renal and Vascular End-stage Disease (PREVEND) cohort.

    PubMed

    Demissei, Biniyam G; Postmus, Douwe; Valente, Mattia A; van der Harst, Pim; van Gilst, Wijk H; Van den Heuvel, Edwin R; Hillege, Hans L

    2015-01-01

    Competing non-cardiovascular related deaths were not accounted for in the Systematic COronary Risk Evaluation (SCORE) model. In this study we assessed the impact of non-cardiovascular related deaths on the prognostic performance and yield of the SCORE model. 5,752 participants from the Prevention of Renal and Vascular End stage Disease cohort aged 40 years and older who were free of atherosclerotic cardiovascular disease (CVD) at baseline were included. A cause-specific hazards (CSH) CVD-related mortality prediction model that accounted for non-CVD-related deaths was developed. The prognostic performance of this model was then compared with a refitted SCORE model. During a median follow-up period of 12.5 years, 139 CVD and 495 non-CVD-related deaths were reported. Discriminatory performance was comparable between the models (C-index = 0.64). The models showed good calibration although the CSH model underestimated risk in the highest decile while the refitted SCORE model showed overestimation. The CSH model classified more non-events into the low risk group compared to the refitted SCORE model (n = 51), yet it was accompanied by a misclassification of six events into the low risk group. The refitted SCORE model classified more individuals as high risk. However, the potential overtreatment that may result from utilizing the refitted SCORE model, when compared with the CSH model, still falls within acceptable limits. Our findings do not support the incorporation of non-cardiovascular mortality into the estimation of total cardiovascular risk in the SCORE model. PMID:25377534

  3. Intra-articular administration of lidocaine in anaesthetized dogs: pharmacokinetic profile and safety on cardiovascular and nervous systems.

    PubMed

    Di Salvo, A; Bufalari, A; De Monte, V; Cagnardi, P; Marenzoni, M L; Catanzaro, A; Vigorito, V; Della Rocca, G

    2015-08-01

    The intra-articular administration of lidocaine is a frequent practice in human orthopaedic surgical procedures, but an eventual absorption of the drug into the bloodstream can lead to toxicity, mainly concerning the central nervous system and the cardiovascular systems. The purpose of this study was to determine the pharmacokinetic profile and the safety, in terms of cardiovascular and CNS toxicity, of lidocaine after intra-articular administration to anesthetized dogs undergoing arthroscopy. Lidocaine 2% was administered to eight dogs before surgery in differing amounts, depending on the volume of the joints involved, and blood samples were taken at predetermined time points. The maximum serum concentration of lidocaine ranged from 0.50 to 3.01 ?g/mL (mean ± SD: 2.18 ± 0.91 ?g/mL), and the time to reach it was 28.75 ± 15.74 min. No signs of cardiac toxicity were detected during the entire procedure, and possible signs of CNS toxicity were masked by the anaesthesia. However, concentrations reported in literature as responsible for neurotoxicity in dog were achieved in three of eight investigated subjects. Pending further studies, veterinarians should consider the possibility of side effects occurring following the intra-articular administration of local anaesthetics. PMID:25428796

  4. Adrenergic System Activation Mediates Changes in Cardiovascular and Psychomotoric Reactions in Young Individuals after Red Bull© Energy Drink Consumption

    PubMed Central

    Cavka, Ana; Stupin, Marko; Panduric, Ana; Plazibat, Ana; Cosic, Anita; Rasic, Lidija; Debeljak, Zeljko; Martinovic, Goran; Drenjancevic, Ines

    2015-01-01

    Objectives. To assess the effect of Red Bull© on (1) blood glucose and catecholamine levels, (2) cardiovascular and respiratory function changes before, during, and after exercise, (3) reaction time, (4) cognitive functions, and (5) response to mental stress test and emotions in young healthy individuals (N=38). Methods. Heart rate (HR) and arterial blood pressure (ABP), blood glucose, adrenaline, and noradrenalin plasma levels were measured before and after Red Bull© intake. Participants were subjected to 4 different study protocols by randomized order, before and 30 minutes after consumption of 500?mL of Red Bull©. Results. Mean ABP and HR were significantly increased at rest after Red Bull© intake. Blood glucose level and plasma catecholamine levels significantly increased after Red Bull© consumption. Heart rate, respiration rate, and respiratory flow rate were significantly increased during exercise after Red Bull© consumption compared to control condition. Intake of Red Bull© significantly improved reaction time, performance in immediate memory test, verbal fluency, and subject's attention as well as performance in mental stress test. Conclusion. This study demonstrated that Red Bull© has beneficial effect on some cognitive functions and effect on cardiovascular and respiratory system at rest and during exercise by increasing activity of the sympathetic nervous system.

  5. CSU Research Colloquium Cardiovascular Research at CSU

    E-print Network

    Stephens, Graeme L.

    that focuses on understanding the cellular and molecular bases of cardiovascular function in health and disease-top to bed-side efforts to understand and develop new interventions for cardiovascular disease in people CSU Research Colloquium Cardiovascular Research at CSU: Molecules, Models and Mankind Hilton Fort

  6. Having a Change of Heart: A Lesson on Cardiovascular Anatomy

    NSDL National Science Digital Library

    Cynthia Pfirrmann (Scotch Plains-Fanwood High School)

    2006-08-01

    This teaching resource was developed by a K-12 science teacher in the American Physiologycal Society's 2006 Frontiers in Physiology Program. For more information on this program, please visit www.frontiersinphys.org. The purpose of this activity is to investigate and develop a model of the normal anatomy of the human heart/circulatory system and then to explore and model the effects of several cardiovascular disease processes. Students should understand basic cellular respiration. Upon completion of this activity, students will be able to: plan and design a model of a human heart with basic systemic circulation and evaluate impact of cardiovascular diseases on normal circulation.

  7. Cardiovascular Effects Of Weightlessness

    NASA Technical Reports Server (NTRS)

    Sandler, Harold

    1992-01-01

    NASA technical memorandum presents study of effects of weightlessness and simulations upon cardiovascular systems of humans and animals. Reviews research up to year 1987 in United States and Soviet space programs on such topics as physiological changes induced by weightlessness in outer space and by subsequent return to Earth gravity and also reviews deconditioning effects of prolonged bed rest on ground.

  8. Optimal prehospital cardiovascular care

    Microsoft Academic Search

    Jane H. Brice; Terence Valenzuela; Joseph P. Ornato; Robert A. Swor; Jerry Overton; Ronald G. Pirrallo; James Dunford; Robert M. Domeier

    2001-01-01

    Optimal prehospital cardiovascular care may improve the morbidity and mortality associated with acute myocardial infarctions (AMIs) that begin in the community. Reducing the time delays from AMI symptom onset to intervention begins with maximizing effective patient education to reduce patient delay in recognizing symptoms and seeking assistance. Transportation delays can be minimized by appropriate use of 911 systems and improving

  9. Molecular mechanisms mediating mitochondrial dynamics and mitophagy and their functional roles in the cardiovascular system.

    PubMed

    Ikeda, Yoshiyuki; Shirakabe, Akihiro; Brady, Christopher; Zablocki, Daniela; Ohishi, Mitsuru; Sadoshima, Junichi

    2015-01-01

    Mitochondria are essential organelles that produce the cellular energy source, ATP. Dysfunctional mitochondria are involved in the pathophysiology of heart disease, which is associated with reduced levels of ATP and excessive production of reactive oxygen species. Mitochondria are dynamic organelles that change their morphology through fission and fusion in order to maintain their function. Fusion connects neighboring depolarized mitochondria and mixes their contents to maintain membrane potential. In contrast, fission segregates damaged mitochondria from intact ones, where the damaged part of mitochondria is subjected to mitophagy whereas the intact part to fusion. It is generally believed that mitochondrial fusion is beneficial for the heart, especially under stress conditions, because it consolidates the mitochondria's ability to supply energy. However, both excessive fusion and insufficient fission disrupt the mitochondrial quality control mechanism and potentiate cell death. In this review, we discuss the role of mitochondrial dynamics and mitophagy in the heart and the cardiomyocytes therein, with a focus on their roles in cardiovascular disease. This article is part of a Special Issue entitled "Mitochondria: From Basic Mitochondrial Biology to Cardiovascular Disease". PMID:25305175

  10. Continuous system modeling

    NASA Technical Reports Server (NTRS)

    Cellier, Francois E.

    1991-01-01

    A comprehensive and systematic introduction is presented for the concepts associated with 'modeling', involving the transition from a physical system down to an abstract description of that system in the form of a set of differential and/or difference equations, and basing its treatment of modeling on the mathematics of dynamical systems. Attention is given to the principles of passive electrical circuit modeling, planar mechanical systems modeling, hierarchical modular modeling of continuous systems, and bond-graph modeling. Also discussed are modeling in equilibrium thermodynamics, population dynamics, and system dynamics, inductive reasoning, artificial neural networks, and automated model synthesis.

  11. Assessing influence of conductivity in heart modelling with the aim of studying cardiovascular diseases

    NASA Astrophysics Data System (ADS)

    Sebastian, Rafael; Ordas, Sebastian; Plank, Gernot; Rodriguez, Blanca; Vigmond, Edward J.; Frangi, Alejandro F.

    2008-03-01

    The bidomain/monodomain equations have been widely used to model electrical activity in cardiac tissue. Here we present a sensitivity study of a crucial parameter in the bidomain model, the tissue conductivity. This study is necessary since there is no general agreement on the actual values that should be employed, mainly due to inconsistencies between the few sources of empirical information existent in the literature. Furthermore, estimates of this parameter from either imaging techniques or from experiments on isolated cardiac tissue have been inconsistent. For this study, a 3D biventricular model built from Multi-Detector Computer Tomography was used with the most relevant electrical structures, such as myocardial fiber orientation and the Purkinje system, were included. Specific ionic models for normal myocardium and for the Purkinje system were taken into account. Finite Element methods were used to solve the monodomain equation for a number of different conductivity settings. Comparative results using isochronal maps are shown in combination with statistical tests to measure changes in the sequence of electrical activation in the myocardium, conduction velocities (CV), and local activation times (LAT).

  12. [Cardiovascular pharmacogenomics].

    PubMed

    Scibona, Paula; Angriman, Federico; Simonovich, Ventura; Heller, Martina M; Belloso, Waldo H

    2014-01-01

    Cardiovascular disease remains a major cause of morbidity and mortality worldwide. Current medical practice takes into account information based on population studies and benefits observed in large populations or cohorts. However, individual patients present great differences in both toxicity and clinical efficacy that can be explained by variations in adherence, unknown drug to drug interactions and genetic variability. The latter seems to explain from 20% up to 95% of patient to patient variability. Treating patients with cardiovascular disorders faces the clinician with the challenge to include genomic analysis into daily practice. There are several examples within cardiovascular disease of treatments that can vary in toxicity or clinical usefulness based on genetic changes. One of the main factors affecting the efficacy of Clopidogrel is the phenotype associated with polymorphisms in the gene CYP 2C9. Furthermore, regarding oral anticoagulants, changes in CYP2C9 and VKORC1 play an important role in changing the clinical response to anticoagulation. When analyzing statin treatment, one of their main toxicities (myopathy) can be predicted by the SLCO1B1 polymorphism. The potential for prediction of toxicity and clinical efficacy from the use of genetic analysis warrants further studies aiming towards its inclusion in daily clinical practice. PMID:24636047

  13. Society for Cardiovascular Magnetic Resonance guidelines for reporting cardiovascular magnetic resonance examinations

    PubMed Central

    Hundley, W Gregory; Bluemke, David; Bogaert, Jan G; Friedrich, Matthias G; Higgins, Charles B; Lawson, Mark A; McConnell, Michael V; Raman, Subha V; van Rossum, Albert C; Flamm, Scott; Kramer, Christopher M; Nagel, Eike; Neubauer, Stefan

    2009-01-01

    These reporting guidelines are recommended by the Society for Cardiovascular Magnetic Resonance (SCMR) to provide a framework for healthcare delivery systems to disseminate cardiac and vascular imaging findings related to the performance of cardiovascular magnetic resonance (CMR) examinations. PMID:19257889

  14. Model performance evaluation (validation and calibration) in model-based studies of therapeutic interventions for cardiovascular diseases : a review and suggested reporting framework.

    PubMed

    Haji Ali Afzali, Hossein; Gray, Jodi; Karnon, Jonathan

    2013-04-01

    Decision analytic models play an increasingly important role in the economic evaluation of health technologies. Given uncertainties around the assumptions used to develop such models, several guidelines have been published to identify and assess 'best practice' in the model development process, including general modelling approach (e.g., time horizon), model structure, input data and model performance evaluation. This paper focuses on model performance evaluation. In the absence of a sufficient level of detail around model performance evaluation, concerns regarding the accuracy of model outputs, and hence the credibility of such models, are frequently raised. Following presentation of its components, a review of the application and reporting of model performance evaluation is presented. Taking cardiovascular disease as an illustrative example, the review investigates the use of face validity, internal validity, external validity, and cross model validity. As a part of the performance evaluation process, model calibration is also discussed and its use in applied studies investigated. The review found that the application and reporting of model performance evaluation across 81 studies of treatment for cardiovascular disease was variable. Cross-model validation was reported in 55 % of the reviewed studies, though the level of detail provided varied considerably. We found that very few studies documented other types of validity, and only 6 % of the reviewed articles reported a calibration process. Considering the above findings, we propose a comprehensive model performance evaluation framework (checklist), informed by a review of best-practice guidelines. This framework provides a basis for more accurate and consistent documentation of model performance evaluation. This will improve the peer review process and the comparability of modelling studies. Recognising the fundamental role of decision analytic models in informing public funding decisions, the proposed framework should usefully inform guidelines for preparing submissions to reimbursement bodies. PMID:23456647

  15. SMARTHealth India: Development and Field Evaluation of a Mobile Clinical Decision Support System for Cardiovascular Diseases in Rural India

    PubMed Central

    Patel, Anushka; Raghu, Arvind; Clifford, Gari D; Maulik, Pallab K; Mohammad Abdul, Ameer; Mogulluru, Kishor; Tarassenko, Lionel; MacMahon, Stephen; Peiris, David

    2014-01-01

    Background Cardiovascular disease (CVD) is the major cause of premature death and disability in India and yet few people at risk of CVD are able to access best practice health care. Mobile health (mHealth) is a promising solution, but very few mHealth interventions have been subjected to robust evaluation in India. Objective The objectives were to develop a multifaceted, mobile clinical decision support system (CDSS) for CVD management and evaluate it for use by public nonphysician health care workers (NPHWs) and physicians in a rural Indian setting. Methods Plain language clinical rules were developed based on standard guidelines and programmed into a computer tablet app. The algorithm was validated and field-tested in 11 villages in Andhra Pradesh, involving 11 NPHWs and 3 primary health center (PHC) physicians. A mixed method evaluation was conducted comprising clinical and survey data and in-depth patient and staff interviews to understand barriers and enablers to the use of the system. Then this was thematically analyzed using NVivo 10. Results During validation of the algorithm, there was an initial agreement for 70% of the 42 calculated variables between the CDSS and SPSS software outputs. Discrepancies were identified and amendments were made until perfect agreement was achieved. During field testing, NPHWs and PHC physicians used the CDSS to screen 227 and 65 adults, respectively. The NPHWs identified 39% (88/227) of patients for referral with 78% (69/88) of these having a definite indication for blood pressure (BP)-lowering medication. However, only 35% (24/69) attended a clinic within 1 month of referral, with 42% (10/24) of these reporting continuing medications at 3-month follow-up. Physicians identified and recommended 17% (11/65) of patients for BP-lowering medications. Qualitative interviews identified 3 interrelated interview themes: (1) the CDSS had potential to change prevailing health care models, (2) task-shifting to NPHWs was the central driver of change, and (3) despite high acceptability by end users, actual transformation was substantially limited by system-level barriers such as patient access to doctors and medicines. Conclusions A tablet-based CDSS implemented within primary health care systems has the potential to help improve CVD outcomes in India. However, system-level barriers to accessing medical care limit its full impact. These barriers need to be actively addressed for clinical innovations to be successful. Trial Registration Clinical Trials Registry of India: CTRI/2013/06/003753; http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=6259&EncHid=51761.70513&userName=CTRI/2013/06/003753 (Archived by WebCite at http://www.webcitation.org/6UBDlrEuq). PMID:25487047

  16. Systemic arterial baroreceptors in ducks and the consequences of their denervation on some cardiovascular responses to diving

    PubMed Central

    Jones, D. R.

    1973-01-01

    1. In the duck systemic arterial baroreceptors which cause bradycardia in response to induced hypertension are located in the walls of the ascending aorta, innervated by the depressor nerves. 2. The location of the baroreceptors was confirmed both histologically and by recording activity from the depressor nerve. Stimulation of the central cut end of a depressor nerve caused transient bradycardia and a fall in blood pressure which was maintained throughout the period of stimulation. 3. Cardiovascular adjustments to submergence of 2 min duration were monitored in intact, sham-operated and denervated ducks. The sham-operated and denervated ducks were used in the experiments some 20-50 days post-operation. The denervations were checked at post-mortem. 4. In the first series of experiments on young ducks mean arterial pressure during a 2 min dive fell by 30% in intact, 17·5% in sham-operated, and 48% in denervated ducks. In all ducks heart rate was reduced by 84-85%. 5. In a second series of experiments on older ducks sciatic artery blood flow was also recorded and mean arterial blood pressure fell by 9·2% in intact and by 53% in denervated animals, although there were no significant differences in heart rate during the 2 min dives. In normal animals sciatic vascular resistance increased after 2 min submergence by 7·86 ± 1·7 times, whereas in denervated ducks it increased by only 2·32 ± 0·5 times. 6. The role of systemic arterial baroreceptors in generation of the cardiovascular responses to submergence in ducks is discussed in terms of the input supplied by the baroreceptors to the central nervous system. ImagesPlate 1 PMID:4764429

  17. Persistent release of IL-1s from skin is associated with systemic cardio-vascular disease, emaciation and systemic amyloidosis: the potential of anti-IL-1 therapy for systemic inflammatory diseases.

    PubMed

    Yamanaka, Keiichi; Nakanishi, Takehisa; Saito, Hiromitsu; Maruyama, Junko; Isoda, Kenichi; Yokochi, Ayumu; Imanaka-Yoshida, Kyoko; Tsuda, Kenshiro; Kakeda, Masato; Okamoto, Ryuji; Fujita, Satoshi; Iwakura, Yoichiro; Suzuki, Noboru; Ito, Masaaki; Maruyama, Kazuo; Gabazza, Esteban C; Yoshida, Toshimichi; Shimaoka, Motomu; Mizutani, Hitoshi

    2014-01-01

    The skin is an immune organ that contains innate and acquired immune systems and thus is able to respond to exogenous stimuli producing large amount of proinflammatory cytokines including IL-1 and IL-1 family members. The role of the epidermal IL-1 is not limited to initiation of local inflammatory responses, but also to induction of systemic inflammation. However, association of persistent release of IL-1 family members from severe skin inflammatory diseases such as psoriasis, epidermolysis bullosa, atopic dermatitis, blistering diseases and desmoglein-1 deficiency syndrome with diseases in systemic organs have not been so far assessed. Here, we showed the occurrence of severe systemic cardiovascular diseases and metabolic abnormalities including aberrant vascular wall remodeling with aortic stenosis, cardiomegaly, impaired limb and tail circulation, fatty tissue loss and systemic amyloid deposition in multiple organs with liver and kidney dysfunction in mouse models with severe dermatitis caused by persistent release of IL-1s from the skin. These morbid conditions were ameliorated by simultaneous administration of anti-IL-1? and IL-1? antibodies. These findings may explain the morbid association of arteriosclerosis, heart involvement, amyloidosis and cachexia in severe systemic skin diseases and systemic autoinflammatory diseases, and support the value of anti-IL-1 therapy for systemic inflammatory diseases. PMID:25119884

  18. Persistent Release of IL-1s from Skin Is Associated with Systemic Cardio-Vascular Disease, Emaciation and Systemic Amyloidosis: The Potential of Anti-IL-1 Therapy for Systemic Inflammatory Diseases

    PubMed Central

    Yamanaka, Keiichi; Nakanishi, Takehisa; Saito, Hiromitsu; Maruyama, Junko; Isoda, Kenichi; Yokochi, Ayumu; Imanaka-Yoshida, Kyoko; Tsuda, Kenshiro; Kakeda, Masato; Okamoto, Ryuji; Fujita, Satoshi; Iwakura, Yoichiro; Suzuki, Noboru; Ito, Masaaki; Maruyama, Kazuo; Gabazza, Esteban C.; Yoshida, Toshimichi; Shimaoka, Motomu; Mizutani, Hitoshi

    2014-01-01

    The skin is an immune organ that contains innate and acquired immune systems and thus is able to respond to exogenous stimuli producing large amount of proinflammatory cytokines including IL-1 and IL-1 family members. The role of the epidermal IL-1 is not limited to initiation of local inflammatory responses, but also to induction of systemic inflammation. However, association of persistent release of IL-1 family members from severe skin inflammatory diseases such as psoriasis, epidermolysis bullosa, atopic dermatitis, blistering diseases and desmoglein-1 deficiency syndrome with diseases in systemic organs have not been so far assessed. Here, we showed the occurrence of severe systemic cardiovascular diseases and metabolic abnormalities including aberrant vascular wall remodeling with aortic stenosis, cardiomegaly, impaired limb and tail circulation, fatty tissue loss and systemic amyloid deposition in multiple organs with liver and kidney dysfunction in mouse models with severe dermatitis caused by persistent release of IL-1s from the skin. These morbid conditions were ameliorated by simultaneous administration of anti-IL-1? and IL-1? antibodies. These findings may explain the morbid association of arteriosclerosis, heart involvement, amyloidosis and cachexia in severe systemic skin diseases and systemic autoinflammatory diseases, and support the value of anti-IL-1 therapy for systemic inflammatory diseases. PMID:25119884

  19. Examination of the use of human sera as an exposure agent for in vitro studies investigating the effects of cigarette smoking on cellular cardiovascular disease models.

    PubMed

    McQuillan, Karina; Carr, Tony; Taylor, Mark; Bishop, Emma; Fearon, Ian M

    2015-08-01

    In vitro models of smoking-related diseases and disease processes are valuable for mechanistic understanding and assessment of novel tobacco products. Many laboratories have used particulate phase or aqueous extracts of cigarette smoke as an exposure system for in vitro models. However, this may not be the most relevant method of exposing cells to smoke and its toxicants. Here we have examined the use of human serum as an exposure system. Cultured human umbilical vein endothelial cells were exposed in vitro to sera (50% dilution in culture media) from human volunteers (9 smokers; 10 non-smokers) for 20h. Statistically-significant differential changes were detected in endothelial migration in an endothelial damage repair model, such that smokers' sera had an inhibitory effect on migration compared with sera from non-smokers (p<0.05). We further observed several statistically-significant differences in cardiovascular disease (CVD)-relevant gene expression between cells exposed to smokers' and non-smokers' sera, as well as differences in levels of cytokines secreted from endothelial cells. Our data demonstrate that human sera from smokers and non-smokers can differentially regulate endothelial function. We suggest that human serum provides a relevant exposure medium for in vitro studies assessing the impact of cigarette smoking on CVD risk potential. PMID:25800949

  20. The actions of the renin-angiotensin system on cardiovascular and osmoregulatory function in embryonic chickens (Gallus gallus domesticus).

    PubMed

    Mueller, Casey A; Crossley, Dane A; Burggren, Warren W

    2014-12-01

    Using embryonic chickens (Gallus gallus domesticus), we examined the role of the renin-angiotensin system (RAS) in cardiovascular and osmotic homeostasis through chronic captopril, an angiotensin-converting enzyme (ACE) inhibitor. Captopril (5 mg kg?¹ embryo wet mass) or saline (control) was delivered via the egg air cell daily from embryonic day 5-18. Mean arterial pressure (MAP), heart rate (ƒ(H)), fluid osmolality and ion concentration, and embryonic and organ masses were measured on day 19. Exogenous angiotensin I (ANG I) injection did not change MAP or ƒ(H) in captopril-treated embryos, confirming ACE inhibition. Captopril-treated embryos were significantly hypotensive, with MAP 15% lower than controls, which we attributed to the loss of vasoconstrictive ANG II action. Exogenous ANG II induced a relatively greater hypertensive response in captopril-treated embryos compared to controls. Changes in response to ANG II following pre-treatment with phentolamine (?-adrenergic antagonist) indicated a portion of the ANG II response was due to circulating catecholamines in captopril-treated embryos. An increase in MAP and ƒ(H) in response to hexamethonium indicated vagal tone was also increased in the absence of ACE activity. Captopril-treated embryos had lower osmolality, lower Na? and higher K? concentration in the blood, indicating osmoregulatory changes. Larger kidney mass in captopril-treated embryos suggests disrupting the RAS may stimulate kidney growth by decreasing resistance at the efferent arteriole and increasing the fraction of cardiac output to the kidneys. This study suggests that the RAS, most likely through ANG II action, influences the development of the cardiovascular and osmoregulatory systems. PMID:25149042

  1. Body mass index trajectories and predictors among 3rd to 12th graders using growth curve mixture modeling the Child and Adolescent Trial for Cardiovascular Health (CATCH) study

    Microsoft Academic Search

    Hao T Duong

    2009-01-01

    This dissertation examined body mass index (BMI) growth trajectories and the effects of gender, ethnicity, dietary intake, and physical activity (PA) on BMI growth trajectories among 3rd to 12th graders (9-18 years of age). Growth curve model analysis was performed using data from The Child and Adolescent Trial for Cardiovascular Health (CATCH) study. The study population included 2909 students who

  2. Problem Set 4 for Biomath 213: Due March 5, 2011 1. Calculate the KortewegMoens velocity for the canine cardiovascular system,

    E-print Network

    Grether, Gregory

    for the canine cardiovascular system, given that the canine aorta has a vessel wall thickness of 2 mm, a radius this information, what value of R corresponds to |k|R=1 for a shrew? How does this answer compare to 2 c? c

  3. Relationship of plasma interleukin-18 concentrations to traditional and non-traditional cardiovascular risk factors in patients with systemic lupus erythematosus

    Microsoft Academic Search

    Tim K. Tso; Wen-Nan Huang; Hui-Yu Huang; Chen-Kang Chang

    2006-01-01

    Objectives. Systemic lupus erythematosus (SLE) is associated with premature atherosclerosis. Recent studies indicated that the concentrations of circulating interleukin (IL)-18, a novel proinflammatory T helper-1 cytokine, in SLE patients were significantly higher than those in healthy control subjects. The objective of this study was to examine the relationship between IL-18 and cardiovascular risk factors in patients with SLE. Methods. Both

  4. Comparing Different Policy Scenarios to Reduce the Consumption of Ultra-Processed Foods in UK: Impact on Cardiovascular Disease Mortality Using a Modelling Approach

    PubMed Central

    Moreira, Patricia V. L.; Baraldi, Larissa Galastri; Moubarac, Jean-Claude; Monteiro, Carlos Augusto; Newton, Alex; Capewell, Simon; O’Flaherty, Martin

    2015-01-01

    Background The global burden of non-communicable diseases partly reflects growing exposure to ultra-processed food products (UPPs). These heavily marketed UPPs are cheap and convenient for consumers and profitable for manufacturers, but contain high levels of salt, fat and sugars. This study aimed to explore the potential mortality reduction associated with future policies for substantially reducing ultra-processed food intake in the UK. Methods and Findings We obtained data from the UK Living Cost and Food Survey and from the National Diet and Nutrition Survey. By the NOVA food typology, all food items were categorized into three groups according to the extent of food processing: Group 1 describes unprocessed/minimally processed foods. Group 2 comprises processed culinary ingredients. Group 3 includes all processed or ultra-processed products. Using UK nutrient conversion tables, we estimated the energy and nutrient profile of each food group. We then used the IMPACT Food Policy model to estimate reductions in cardiovascular mortality from improved nutrient intakes reflecting shifts from processed or ultra-processed to unprocessed/minimally processed foods. We then conducted probabilistic sensitivity analyses using Monte Carlo simulation. Results Approximately 175,000 cardiovascular disease (CVD) deaths might be expected in 2030 if current mortality patterns persist. However, halving the intake of Group 3 (processed) foods could result in approximately 22,055 fewer CVD related deaths in 2030 (minimum estimate 10,705, maximum estimate 34,625). An ideal scenario in which salt and fat intakes are reduced to the low levels observed in Group 1 and 2 could lead to approximately 14,235 (minimum estimate 6,680, maximum estimate 22,525) fewer coronary deaths and approximately 7,820 (minimum estimate 4,025, maximum estimate 12,100) fewer stroke deaths, comprising almost 13% mortality reduction. Conclusions This study shows a substantial potential for reducing the cardiovascular disease burden through a healthier food system. It highlights the crucial importance of implementing healthier UK food policies. PMID:25679527

  5. Phase dependencies between longitudinal corneal apex displacement of human eye and cardiovascular system

    NASA Astrophysics Data System (ADS)

    Danielewska, M.; Kowalska, M.; Kasprzak, H.

    2008-12-01

    Intraocular pressure (IOP) varies quasi-periodically due to blood pulsation in vessels inside the eye globe. This variations cause the eye deformations and displacements of the outer surface of the eye. The aim of this paper is to calculate the correlation between longitudinal corneal apex displacement and cardiovascular activity. Using ultrasound transducer at sampling frequency of 100Hz we have measured longitudinal corneal apex displacement (LCAD) of the left eye for 5 subjects. Synchronically we have registered ECG and blood pulsation signals at the same sampling frequency. Cross-correlation function was applied to investigate dependencies between these signals. To find time shift between LCAD and ECG or pulse, the time window of 3 seconds length have been chosen from all signals and had been shifting with the step of 0.01 seconds from 0 to 7s. For each shift the cross-correlation function and its extrema were calculated in the window area. We have obtained information about extrema position of cross-correlation function and its stability in time for particular subjects. The time shift between LCAD and ECG or pulse is individual feature of each subject. Such calculations may lead us to better understanding of pulse propagation in human eye and creation a non invasive method of eye hemodynamics and ocular diagnosis.

  6. Adeno-associated virus vectors as therapeutic and investigational tools in the cardiovascular system.

    PubMed

    Zacchigna, Serena; Zentilin, Lorena; Giacca, Mauro

    2014-05-23

    The use of vectors based on the small parvovirus adeno-associated virus has gained significant momentum during the past decade. Their high efficiency of transduction of postmitotic tissues in vivo, such as heart, brain, and retina, renders these vectors extremely attractive for several gene therapy applications affecting these organs. Besides functional correction of different monogenic diseases, the possibility to drive efficient and persistent transgene expression in the heart offers the possibility to develop innovative therapies for prevalent conditions, such as ischemic cardiomyopathy and heart failure. Therapeutic genes are not only restricted to protein-coding complementary DNAs but also include short hairpin RNAs and microRNA genes, thus broadening the spectrum of possible applications. In addition, several spontaneous or engineered variants in the virus capsid have recently improved vector efficiency and expanded their tropism. Apart from their therapeutic potential, adeno-associated virus vectors also represent outstanding investigational tools to explore the function of individual genes or gene combinations in vivo, thus providing information that is conceptually similar to that obtained from genetically modified animals. Finally, their single-stranded DNA genome can drive homology-directed gene repair at high efficiency. Here, we review the main molecular characteristics of adeno-associated virus vectors, with a particular view to their applications in the cardiovascular field. PMID:24855205

  7. Adrenomedullin gene expression and levels in the cardiovascular system after treatment with lipopolysaccharide.

    PubMed

    Li, Yuk-Yin; Cheung, Bernard M Y; Wong, Louisa Y F; Hwang, Isabel S S; Kumana, Cyrus R; Tang, Fai

    2005-04-01

    To study the effect of septicaemia, the temporal changes in tissue adrenomedullin (AM) and preproAM mRNA levels were studied in the heart and blood vessels after lipopolysaccharide (LPS) injection. Radioimmunoassay and solution hybridization-RNase protection assays were used to follow the changes in AM and its mRNA levels respectively after intraperitoneal injection of 10 mg/kg LPS in rats. The preproAM mRNA levels increased at 1 h in the right atrium after LPS injection, while the AM contents decreased at 1 h in the left atrium. The preproAM mRNA levels increased at 3 and 6 h in the left ventricle, whereas it increased at 6 h in the right ventricles after LPS injection. There was an increase in preproAM mRNA levels at 1 and 3 h in the mesenteric artery, while AM levels were increased at 1, 3 and 6 h. However, there were no such changes in the thoracic aorta. There were also increases in tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta and IL-6 in the heart, and in the mesenteric artery (TNF-alpha and IL-1beta) and in thoracic aorta (IL-1beta and IL-6). The present results suggest that the biosynthesis and secretion of AM may be increased in cardiovascular tissues of rats injected with LPS, and that AM may play multiple roles in inflammation. PMID:15752540

  8. Fluorophore-mediated, fiber-optic, multi-analyte, immunosensing system for rapid diagnosis and prognosis of cardiovascular diseases

    NASA Astrophysics Data System (ADS)

    Tang, Liang; Ren, Yongjie; Hong, Bin; Kang, Kyung A.

    2006-03-01

    A prototype of a fiber-optic, multi-analyte, immunobiosensing system was developed to simultaneously quantify disease-representing biomarkers in blood plasma. This system was for simultaneous quantification of two different groups of multi-biomarkers related to cardiovascular diseases (CVD): anticoagulants (protein C, protein S, antithrombin III, and plasminogen) for deficiency diagnosis; and cardiac markers (B-type natriuretic peptide, cardiac troponin I, myoglobin, and C-reactive protein) for coronary heart disease diagnosis. As an initial effort towards the development of a disposable and easy-to-use sensing cartridge as a rapid diagnostic tool for CVD related diseases, a prototype of a flow control system was also developed to automatically perform simultaneous four-analyte quantification. Currently, the system is capable of quantifying the multiple anticoagulants in their clinically significant sensing ranges within 5 minutes, at an average signal-to-noise (S/N) ratio of 25. A simultaneous assay of the four cardiac markers can be performed within 10 min, at an average S/N ratio of 20. When this highly portable multi-analyte sensing system is completed and successfully tested for CVD patient's plasma, it can provide rapid (<10 min) and reliable diagnostic and prognostic information at a patient's bedside.

  9. Multiscale modelling of the circulatory system: a preliminary analysis

    Microsoft Academic Search

    Luca Formaggia; Fabio Nobile; Alfio Quarteroni; Alessandro Veneziani

    1999-01-01

    .   In this paper we show how numerical solutions of human cardiovascular system may be devised by coupling models having different\\u000a physical dimensions. One of the aspects of circulatory system is indeed its multiscale nature. Local flow features may have\\u000a a global effect on circulation. For instance, a stenosis caused by an atherosclerotic plaque may change the overall characteristic\\u000a of

  10. Earth System Modeling

    NASA Astrophysics Data System (ADS)

    Jöckel, Patrick

    Earth system models are important research tools for improving understanding of the climate system and for simulating climate projections. This chapter is devoted to the basic construction principles and challenges of such models, whereas application examples are provided in companion chapters. Since they still do not incorporate the full complexity of the real climate system (and maybe never will), Earth system models nowadays typically focus on specific aspects, for instance on the role of chemically active substances in the climate system.

  11. System Design Conceptual Model

    Microsoft Academic Search

    Kari Tiensyrjä; Jean Mermet

    This chapter presents the foundations of the System Design Conceptual Model (SDCM). The SDCM is a meta-model that serves as\\u000a a reference model of, and gives a global view and perspective on system design. The SDCM is used to describe system design\\u000a from the viewpoints of the System Design Process (SDP) and the System Under Design (SUD). The SDP and

  12. Modelling Distributed Systems

    E-print Network

    Yonezawa, Akinori

    1977-06-01

    Distributed systems are multi-processor information processing systems which do not rely on the central shared memory for communication. This paper presents ideas and techniques in modelling distributed systems and ...

  13. Effect of docosahexaenoic acid monoacylglyceride on systemic hypertension and cardiovascular dysfunction.

    PubMed

    Morin, Caroline; Rousseau, Eric; Blier, Pierre U; Fortin, Samuel

    2015-07-01

    ?-3 Fatty acid supplementation has been associated with lower blood pressure. Cardiovascular diseases are also known to be linked directly to an increase in ?-6 and a reduction in ?-3 fatty acid levels in blood circulation and tissues. To determine the effect of docosahexaenoic acid monoglycerides (MAG-DHA) on blood pressure, lipid profiles, and vascular remodeling in rats fed a high-fat/high-carbohydrate (HFHC) diet. Studies were performed in male rats subjected to 8 wk of HFHC diet supplemented or not with 3 g/day MAG-DHA. After 8 wk of daily MAG-DHA treatment, rats in the HFHC + MAG-DHA group had lower arterial blood pressure and heart rate compared with the HFHC group. Moreover, MAG-DHA prevented the increase aortic wall thickness, whereas lipid analysis of aortic tissues revealed an increase in DHA/AA ratio correlated with the production of resolvin D2 and D3 metabolites. Histological analysis revealed that MAG-DHA prevented the development of LVH in the HFHC group. Serum lipid profile analysis further showed a decrease in total cholesterol (TC) and LDL, including very low-density lipoprotein (VLDL) and triglyceride (TG) levels, together with an increase in HDL levels after 8 wk of MAG-DHA treatment compared with the HFHC group. Furthermore, daily MAG-DHA treatment resulted in reduced proinflammatory marker levels such as CRP, IL-6, TNF?, and IL-1?. Altogether, these findings revealed that per os administration of MAG-DHA prevents HFHC-diet induced hypertension and LVH in rats. PMID:25910811

  14. [Quality management in cardiovascular echography].

    PubMed

    Gullace, Giuseppe

    2002-12-01

    The quality management of an organization can be defined as the ability to identify, plan and implement programs of measure, analysis, verification and control that allow to monitor management, resources, activities, processes and output/outcome of the same organization, including the satisfaction of the customers. Whatever the model used, it is demonstrated that the management-quality system, either for professional quality or for organization, turns out to be effective even in the health organizations within and to any level of organizational-structural complexity. The present paper concerns the experience of the Italian Society of Cardiovascular Echography (SIEC) on quality certification, both as a scientific society compared to other health organizations and to cardiovascular echo laboratories, and the definition of minimum requirements for the accreditation of the same laboratories. The model most frequently used for quality management is represented by the ISO 9000: Vision 2000, that is a management model with specific reference to the organization and the customer satisfaction. The model applied to the health structure needs a rapid change in mentality that addresses the operators to define, share and achieve objectives to be brought on by means of an active collaboration, group activity and deep sense of belonging necessary to the attainment of expected objectives. When the model is applied by a scientific society, it is necessary to take into account the different structural and functional organization, the constitution and the operators differing on the point of view of origin, experiences, mentality, and roles. The ISO 9000: Vision 2000 model can be applied also to the cardiovascular echo laboratory which may be compared to a simple organization; for its corrected functioning, SIEC has defined minimal requirements for the accreditation, realization and modalities to carry out and manage quality. The quality system represents a new way of operating of an organization that enhances capability and performance of the operators, stimulates their creativity and facilitates the activities of all, to guarantee both the quality of the product and the satisfaction of operators and customers at the same time. PMID:12611211

  15. Adiponectin and cardiovascular inflammatory responses

    Microsoft Academic Search

    Yukihiro Takemura; Kenneth Walsh; Noriyuki Ouchi

    2007-01-01

    Obesity is recognized as a cause of many metabolic and cardiovascular disorders through its ability to promote chronic systemic\\u000a inflammation. Recent studies have found that adipose tissues secrete numerous cytokines that are referred to as adipokines.\\u000a Although most adipokines induce inflammation, adiponectin inhibits inflammatory reactions and protects against metabolic and\\u000a cardiovascular diseases. This review focuses on the anti-inflammatory properties of

  16. Patient interaction in homecare systems to treat cardiovascular diseases in the long term.

    PubMed

    Peinado, Ignacio; Arredondo, Maria Teresa; Villalba, Elena; Salvi, Dario; Ottaviano, Manuel

    2009-01-01

    The rapid aging of the population worldwide will dramatically increase the number of people affected by chronic diseases in the next years. This social situation makes it necessary a paradigm shift from reactive care to preventive care. New technological paradigms, like Ambient Intelligence and Ubiquitous Computing, allow the development of Personal Health Systems (PHS) that guarantee the continuity of care and a better use of health resources. Therefore, patients should become the centre of the health care process, and PHS should be designed to fulfill the patient's goals and needs. User-centred methodologies provide a good framework for designing general use applications, but they do not usually take into account factors like the context where the interaction is taking place or the medical, social and business contexts that surround the patient. This paper presents a model for designing user's interaction in medical applications. The final goal is to develop highly usable user interfaces and to improve the user experience, aiming to guarantee the patient's adherence to the medical protocols and recommendations. PMID:19964214

  17. Pharmacogenomics and Cardiovascular Disease

    PubMed Central

    Weeke, Peter; Roden, Dan M.

    2014-01-01

    Variability in drug responsiveness is a sine qua non of modern therapeutics, and the contribution of genomic variation is increasingly recognized. Investigating the genomic basis for variable responses to cardiovascular therapies has been a model for pharmacogenomics in general and has established critical pathways and specific loci modulating therapeutic responses to commonly used drugs such as clopidogrel, warfarin, and statins. In addition, genomic approaches have defined mechanisms and genetic variants underlying important toxicities with these and other drugs. These findings have not only resulted in changes to the product labels but also have led to development of initial clinical guidelines that consider how to facilitate incorporating genetic information to the bedside. This review summarizes the state of knowledge in cardiovascular pharmacogenomics and considers how variants described to date might be deployed in clinical decision making. PMID:23689943

  18. [The significance of sympathovagal balance in the forming of respiration-dependent oscillations in cardiovascular system in human].

    PubMed

    Krasnikov, G V; Tiurina, M ?; Tankanag, A V; Piskunova, G M; Cheremis, N K

    2014-01-01

    The effect of deep breathing controlled in both rate and amplitude on the heart rate variability (HRV) and respiration-dependent blood flow oscillations of forearm and finger-pad skin has been studied in 29 young healthy volunteers from 18 to 25 years old. To reveal the effect of the segments of the vegetative autonomic nervous system on the amplitudes of HRV and respiration-dependent oscillations of skin blood flow we estimated the parameters of the cardiovascular system into two groups of participants: with formally high and low sympathovagal balance values. The sympathovagal balance value was judged by the magnitude of LF/HF power ratio calculated for each participant using the spontaneous breathing rhythmogram. It was found what the participants with predominant parasympathetic tonus had statistically significant higher amplitudes of H R V and skin blood flow oscillations in the breathing rate less than 4 cycles per min than the subjects with predominant sympathetic tonus. In the forearm skin, where the density of sympathetic innervations is low comparatively to that in the finger skin, no statistically significant differences in the amplitude of respiratory skin blood flow oscillations was found between the two groups of participants. PMID:25272770

  19. Personalized Medicine in Cardiovascular Diseases

    PubMed Central

    Lee, Moo-Sik; Flammer, Andreas J.; Lerman, Lilach O.

    2012-01-01

    Personalized medicine is a novel medical model with all decisions and practices being tailored to individual patients in whatever ways possible. In the era of genomics, personalized medicine combines the genetic information for additional benefit in preventive and therapeutic strategies. Personalized medicine may allow the physician to provide a better therapy for patients in terms of efficiency, safety and treatment length to reduce the associated costs. There was a remarkable growth in scientific publication on personalized medicine within the past few years in the cardiovascular field. However, so far, only very few cardiologists in the USA are incorporating personalized medicine into clinical treatment. We review the concepts, strengths, limitations and challenges of personalized medicine with a particular focus on cardiovascular diseases (CVDs). There are many challenges from both scientific and policy perspectives to personalized medicine, which can overcome them by comprehensive concept and understanding, clinical application, and evidence based practices. Individualized medicine serves a pivotal role in the evolution of national and global healthcare reform, especially, in the CVDs fields. Ultimately, personalized medicine will affect the entire landscape of health care system in the near future. PMID:23091501

  20. Experimental study and constitutive modelling of the passive mechanical properties of the porcine carotid artery and its relation to histological analysis: Implications in animal cardiovascular device trials.

    PubMed

    García, A; Peña, E; Laborda, A; Lostalé, F; De Gregorio, M A; Doblaré, M; Martínez, M A

    2011-07-01

    The present study focusses on the determination, comparison and constitutive modelling of the passive mechanical properties of the swine carotid artery over very long stretches in both proximal and distal regions. Special attention is paid to the histological and mechanical variations of these properties depending on the proximity to the heart. The results can have clinical relevance, especially in the research field of intravascular device design. Before the final clinical trials on humans, research in the vascular area is conducted on animal models, swine being the most common due to the similarities between the human and swine cardiovascular systems as well as the fact that the swine size is suitable for testing devices, in this case endovascular carotid systems. The design of devices usually involves numerical techniques, and an important feature is the appropriate modelling of the mechanical properties of the vessel. Fourteen carotid swine arteries were harvested just after sacrifice and cyclic uniaxial tension tests in longitudinal and circumferential directions were performed for distal and proximal samples. The stress-stretch curves obtained were fitted with a hyperelastic anisotropic model. Stress-free configuration states were also analyzed. Finally, human and swine samples were processed in a histological laboratory and images were used to quantify their microconstituents. The statistical analysis revealed significant differences between the mechanical behavior of proximal and distal locations in the circumferential but not in the longitudinal direction. Circumferential direction samples show clear differences both in residual stretches and tensile curves between the two locations, while the features of longitudinal specimens are independent of the axial position. The statistical analysis provides significant evidence of changes depending on the position of the sample, mainly in elastin and SMC quantification. PMID:21371929

  1. Modular Modeling System Model Builder

    SciTech Connect

    McKim, C.S.; Matthews, M.T. [Framatome Technologies, Lynchburg, VA (United States)

    1996-12-31

    The latest release of the Modular Modeling System (MMS) Model Builder adds still more time-saving features to an already powerful MMS dynamic-simulation tool set. The Model Builder takes advantage of 32-bit architecture within the Microsoft Windows 95/NT{trademark} Operating Systems to better integrate a mature library of power-plant components. In addition, the MMS Library of components can now be modified and extended with a new tool named MMS CompGen{trademark}. The MMS Model Builder allows the user to quickly build a graphical schematic representation for a plant by selecting from a library of predefined power plant components to dynamically simulate their operation. In addition, each component has a calculation subroutine stored in a dynamic-link library (DLL), which facilitates the determination of a steady-state condition and performance of routine calculations for the component. These calculations, termed auto-parameterization, help avoid repetitive and often tedious hand calculations for model initialization. In striving to meet the needs for large models and increase user productivity, the MMS Model Builder has been completely revamped to make power plant model creation and maintainability easier and more efficient.

  2. Large Scale Expansion of Human Umbilical Cord Cells in a Rotating Bed System Bioreactor for Cardiovascular Tissue Engineering Applications

    PubMed Central

    Reichardt, Anne; Polchow, Bianca; Shakibaei, Mehdi; Henrich, Wolfgang; Hetzer, Roland; Lueders, Cora

    2013-01-01

    Widespread use of human umbilical cord cells for cardiovascular tissue engineering requires production of large numbers of well-characterized cells under controlled conditions. In current research projects, the expansion of cells to be used to create a tissue construct is usually performed in static cell culture systems which are, however, often not satisfactory due to limitations in nutrient and oxygen supply. To overcome these limitations dynamic cell expansion in bioreactor systems under controllable conditions could be an important tool providing continuous perfusion for the generation of large numbers of viable pre-conditioned cells in a short time period. For this purpose cells derived from human umbilical cord arteries were expanded in a rotating bed system bioreactor for up to 9 days. For a comparative study, cells were cultivated under static conditions in standard culture devices. Our results demonstrated that the microenvironment in the perfusion bioreactor was more favorable than that of the standard cell culture flasks. Data suggested that cells in the bioreactor expanded 39 fold (38.7 ± 6.1 fold) in comparison to statically cultured cells (31.8 ± 3.0 fold). Large-scale production of cells in the bioreactor resulted in more than 3 x 108 cells from a single umbilical cord fragment within 9 days. Furthermore cell doubling time was lower in the bioreactor system and production of extracellular matrix components was higher. With this study, we present an appropriate method to expand human umbilical cord artery derived cells with high cellular proliferation rates in a well-defined bioreactor system under GMP conditions. PMID:23847691

  3. Modeling of geothermal systems

    SciTech Connect

    Bodvarsson, G.S.; Pruess, K.; Lippmann, M.J.

    1985-03-01

    During the last decade the use of numerical modeling for geothermal resource evaluation has grown significantly, and new modeling approaches have been developed. In this paper we present a summary of the present status in numerical modeling of geothermal systems, emphasizing recent developments. Different modeling approaches are described and their applicability discussed. The various modeling tasks, including natural-state, exploitation, injection, multi-component and subsidence modeling, are illustrated with geothermal field examples. 99 refs., 14 figs.

  4. Exposure Analysis Modeling System

    EPA Science Inventory

    The Exposure Analysis Modeling System (EXAMS) is an interactive software application for formulating aquatic ecosystem models and evaluating the fate, transport, and exposure concentrations of synthetic organic chemicals including pesticides, industrial materials, and leachates f...

  5. Rat Models of Cardiovascular Disease Demonstrate Distinctive Pulmonary Gene Expressions for Vascular Response Genes: Impact of Ozone Exposure

    EPA Science Inventory

    Comparative gene expression profiling of multiple tissues from rat strains with genetic predisposition to diverse cardiovascular diseases (CVD) can help decode the transcriptional program that governs organ-specific functions. We examined expressions of CVD genes in the lungs of ...

  6. Cardiovascular physiology at high altitude.

    PubMed

    Hooper, T; Mellor, A

    2011-03-01

    The role of the cardiovascular system is to deliver oxygenated blood to the tissues and remove metabolic effluent. It is clear that this complex system will have to adapt to maintain oxygen deliver in the profound hypoxia of high altitude. The literature on the adaptation of both the systemic and pulmonary circulations to high altitude is reviewed. PMID:21465906

  7. Developmental plasticity in the cardiovascular system of fish, with special reference to the zebrafish

    Microsoft Academic Search

    Bernd Pelster

    2002-01-01

    During development the circulatory system of vertebrates typically starts operating earlier than any other organ. In these early stages, however, blood flow is not yet linked to metabolic requirements of tissues, as is well established for adults. While the autonomic nervous system becomes functional only quite late during development, in the early stages control of blood flow appears to be

  8. Control and interaction of the cardiovascular and respiratory systems in anuran amphibians

    Microsoft Academic Search

    Tobias Wang; Michael S. Hedrick; Younis M. Ihmied; Edwin W. Taylor

    1999-01-01

    In anuran amphibians, respiratory rhythm is generated within the central nervous system (CNS) and is modulated by chemo- and mechanoreceptors located in the vascular system and within the CNS. The site for central respiratory rhythmogenesis and the role of various neurotransmitters and neuromodulators is described. Ventilatory air flow is generated by a positive pressure, buccal force pump driven by efferent

  9. 77 FR 8117 - Medical Devices; Cardiovascular Devices; Classification of the Endovascular Suturing System

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ...fixation and sealing between an endovascular graft and the native artery. The system is comprised of the implant device and an endovascular...fixation and sealing between an endovascular graft and the native artery. The system is comprised of the implant device and an...

  10. The Systems Integration Modeling System

    SciTech Connect

    Danker, W.J.; Williams, J.R. [USDOE Office of Civilian Radioactive Waste Management, Washington, DC (United States)

    1990-10-01

    This paper discusses the systems integration modeling system (SIMS), an analysis tool for the detailed evaluation of the structure and related performance of the Federal Waste Management System (FWMS) and its interface with waste generators. It`s use for evaluations in support of system-level decisions as to FWMS configurations, the allocation, sizing, balancing and integration of functions among elements, and the establishment of system-preferred waste selection and sequencing methods and other operating strategies is presented. SIMS includes major analysis submodels which quantify the detailed characteristics of individual waste items, loaded casks and waste packages, simulate the detailed logistics of handling and processing discrete waste items and packages, and perform detailed cost evaluations.

  11. A novel video technique for visualizing flow structures in cardiovascular models

    Microsoft Academic Search

    A. P. Shortland; R. A. Black; J. C. Jarvis; S. Salmons

    1996-01-01

    We describe a video system that produces good quality images of particle trajectories in seeded fluid flows. The operation of a liquid crystal optical shutter and a modified charge-coupled device (CCD) camera were synchronized to generate images of particle trajectories which were stored in a framegrabber before being transferred to S-VHS tape. The camera system is particularly appropriate for visualizing

  12. Antioxidant-based therapies for angiotensin II-associated cardiovascular diseases

    PubMed Central

    Rosenbaugh, Erin G.; Savalia, Krupa K.; Manickam, Devika S.

    2013-01-01

    Cardiovascular diseases, including hypertension and heart failure, are associated with activation of the renin-angiotensin system (RAS) and increased circulating and tissue levels of ANG II, a primary effector peptide of the RAS. Through its actions on various cell types and organ systems, ANG II contributes to the pathogenesis of cardiovascular diseases by inducing cardiac and vascular hypertrophy, vasoconstriction, sodium and water reabsorption in kidneys, sympathoexcitation, and activation of the immune system. Cardiovascular research over the past 15–20 years has clearly implicated an important role for elevated levels of reactive oxygen species (ROS) in mediating these pathophysiological actions of ANG II. As such, the use of antioxidants, to reduce the elevated levels of ROS, as potential therapies for various ANG II-associated cardiovascular diseases has been intensely investigated. Although some antioxidant-based therapies have shown therapeutic impact in animal models of cardiovascular disease and in human patients, others have failed. In this review, we discuss the benefits and limitations of recent strategies, including gene therapy, dietary sources, low-molecular-weight free radical scavengers, polyethylene glycol conjugation, and nanomedicine-based technologies, which are designed to deliver antioxidants for the improved treatment of cardiovascular diseases. Although much work has been completed, additional research focusing on developing specific antioxidant molecules or proteins and identifying the ideal in vivo delivery system for such antioxidants is necessary before the use of antioxidant-based therapies for cardiovascular diseases become a clinical reality. PMID:23552499

  13. Radiotherapy and anthracyclines – cardiovascular toxicity

    PubMed Central

    Wo?niewski, Marek

    2014-01-01

    The subject of this paper is to analyze the impact of radiotherapy and anthracyclines on the cardiovascular system, based on a survey of contemporary literature. Currently, high efficiency of anticancer therapies has increased the rate of survival in patients treated for cancer. It should be emphasized, however, that these treatments damage not only the affected but also the healthy tissue. Consequently, with the increase of survival rate in these patients, the number of patients with complaints regarding numerous organs and systems also increases as a result of earlier treatment. Thus, during the first decade of the 21st century, a number of concerns about the relationship between cancer treatment and dysfunction of the cardiovascular system were resolved. Anthracyclines, as well as radiotherapy, are capable of damaging the cardiovascular system, both at the central level, by the deterioration of cardiac function, and at peripheral levels, by increasing the hemodynamic and thrombotic changes.

  14. Determination of the effects of pulmonary arterial hypertension and therapy on the cardiovascular system of rats by impedance cardiography

    PubMed Central

    Buyukakilli, Belgin; Gurgul, Serkan; C?t?r?k, Derya; Hallioglu, Olgu; Ozeren, Murat; Tasdelen, Bahar

    2014-01-01

    Aim To evaluate the effects of bosentan, sildenafil, and combined therapy on the cardiovascular system using impedance cardiography (ICG) in rats with monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Methods Seventy male Wistar-albino rats were randomized into five groups. A single dose of MCT was given to all rats, except to the control group. After 4 weeks, bosentan, sildenafil, and combined treatment was started and lasted for 3 weeks. The last group that developed PAH did not receive any medication. Echocardiographic evaluation was performed to determine the PAH development. Thoracic fluid content index (TFCI), stroke volume index (SI), heart rate (HR), cardiac index (CI), and myocardial contractility index (IC) were determined. All procedures were performed at the baseline and after 4 and 7 weeks. Results Echocardiographic parameters showed that the all MCT-injected rats developed PAH. There were no significant inter- and intra-group differences in TFCI, SI, and IC (P?>?0.05), but at the 7th week, CI value in the sildenafil-treated PAH rats was significantly higher than in other groups and HR of PAH rats with combined therapy was significantly lower than in other groups. Conclusion PAH did not have an effect on LV function of rats, or if it did, the effect was compensated by physiological processes. Also, sildenafil treatment deteriorated the LV cardiac index. PMID:25358882

  15. Dual renin-angiotensin system inhibition for prevention of renal and cardiovascular events: do the latest trials challenge existing evidence?

    PubMed Central

    2013-01-01

    Circulatory and tissue renin-angiotensin systems (RAS) play a central role in cardiovascular (CV) and renal pathophysiology, making RAS inhibition a logical therapeutic approach in the prevention of CV and renal disease in patients with hypertension. The cardio- and renoprotective effects observed with angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) monotherapy, together with the availability of a direct renin inhibitor (DRI), led to the investigation of the potential benefits of dual RAS inhibition. In small studies, ARB and ACE inhibitor combinations were shown to be beneficial in patients with CV or renal disease, with improvement in surrogate markers. However, in larger outcome trials, involving combinations of ACE inhibitors, ARBs or DRIs, dual RAS inhibition did not show reduction in mortality in patients with diabetes, heart failure, coronary heart disease or after myocardial infarction, and was in fact, associated with increased harm. A recent meta-analysis of all major trials conducted over the past 22 years involving dual RAS inhibition has clearly shown that the risk-benefit ratio argues against the use of dual RAS inhibition. Hence, the recent evidence clearly advocates against the use of dual RAS inhibition, and single RAS inhibition appears to be the most suitable approach to controlling blood pressure and improving patient outcomes. PMID:23866091

  16. MLS: Airplane system modeling

    NASA Technical Reports Server (NTRS)

    Thompson, A. D.; Stapleton, B. P.; Walen, D. B.; Rieder, P. F.; Moss, D. G.

    1981-01-01

    Analysis, modeling, and simulations were conducted as part of a multiyear investigation of the more important airplane-system-related items of the microwave landing system (MLS). Particular emphasis was placed upon the airplane RF system, including the antenna radiation distribution, the cabling options from the antenna to the receiver, and the overall impact of the airborne system gains and losses upon the direct-path signal structure. In addition, effort was expended toward determining the impact of the MLS upon the airplane flight management system and developing the initial stages of a fast-time MLS automatic control system simulation model. Results ot these studies are presented.

  17. Patient-specific assessment of cardiovascular function by combination of clinical data and computational model with applications to patients undergoing Fontan operation.

    PubMed

    Liang, Fuyou; Sughimoto, Koichi; Matsuo, Kozo; Liu, Hao; Takagi, Shu

    2014-10-01

    The assessment of cardiovascular function is becoming increasingly important for the care of patients with single-ventricle defects. However, most measurement methods available in the clinical setting cannot provide a separate measure of cardiac function and loading conditions. In the present study, a numerical method has been proposed to compensate for the limitations of clinical measurements. The main idea was to estimate the parameters of a cardiovascular model by fitting model simulations to patient-specific clinical data via parameter optimization. Several strategies have been taken to establish a well-posed parameter optimization problem, including clinical data-matched model development, parameter selection based on an extensive sensitivity analysis, and proper choice of parameter optimization algorithm. The numerical experiments confirmed the ability of the proposed parameter optimization method to uniquely determine the model parameters given an arbitrary set of clinical data. The method was further tested in four patients undergoing the Fontan operation. Obtained results revealed a prevalence of ventricular abnormalities in the patient cohort and at the same time demonstrated the presence of marked inter-patient differences and preoperative to postoperative changes in cardiovascular function. Because the method allows a quick assessment and makes use of clinical data available in clinical practice, its clinical application is promising. PMID:24753499

  18. The importance of the renin-angiotensin system in normal cardiovascular homeostasis

    NASA Technical Reports Server (NTRS)

    Haber, E.

    1975-01-01

    Studies were carried out on adult mongrel dogs (20 to 30 kilograms) to investigate the importance of the renin-angiotensin system. Results indicate that the renin-angiotensin system plays a major role in the maintenance of circulatory homeostasis when extracellular fluid volume is depleted. It was also found that angiotensin II concentration, in addition to renal perfusion pressure, is a factor in the regulation of renin release.

  19. 77 FR 39924 - Effective Date of Requirement for Premarket Approval for Cardiovascular Permanent Pacemaker...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ...for Premarket Approval for Cardiovascular Permanent Pacemaker Electrode...protocol (PDP) for the cardiovascular permanent pacemaker electrode...established a comprehensive system for the regulation of medical...completion of a PDP for the cardiovascular permanent pacemaker...

  20. Integrated Workforce Modeling System

    NASA Technical Reports Server (NTRS)

    Moynihan, Gary P.

    2000-01-01

    There are several computer-based systems, currently in various phases of development at KSC, which encompass some component, aspect, or function of workforce modeling. These systems may offer redundant capabilities and/or incompatible interfaces. A systems approach to workforce modeling is necessary in order to identify and better address user requirements. This research has consisted of two primary tasks. Task 1 provided an assessment of existing and proposed KSC workforce modeling systems for their functionality and applicability to the workforce planning function. Task 2 resulted in the development of a proof-of-concept design for a systems approach to workforce modeling. The model incorporates critical aspects of workforce planning, including hires, attrition, and employee development.

  1. The Intelligent System of Cardiovascular Disease Diagnosis Based on Extension Data Mining

    NASA Astrophysics Data System (ADS)

    Sun, Baiqing; Li, Yange; Zhang, Lin

    This thesis gives the general definition of the concepts of extension knowledge, extension data mining and extension data mining theorem in high dimension space, and also builds the IDSS integrated system by the rough set, expert system and neural network, develops the relevant computer software. From the diagnosis tests, according to the common diseases of myocardial infarctions, angina pectoris and hypertension, and made the test result with physicians, the results shows that the sensitivity, specific and accuracy diagnosis by the IDSS are all higher than the physicians. It can improve the rate of the accuracy diagnosis of physician with the auxiliary help of this system, which have the obvious meaning in low the mortality, disability rate and high the survival rate, and has strong practical values and further social benefits.

  2. Why are patients with chronic obstructive pulmonary disease at increased risk of cardiovascular diseases? The potential role of systemic inflammation in chronic obstructive pulmonary disease

    Microsoft Academic Search

    Don D. Sin; S. F. Paul Man

    2003-01-01

    Background—Chronic obstructive pulmonary disease (COPD) increases the risk of cardiovascular disease 2- to 3- fold. The factors responsible for this association remain largely unknown. Methods and Results—We analyzed data from participants, 50 years of age, of the Third National Health and Nutrition Examination Survey (n6629) to determine whether C-reactive protein (CRP) and other systemic inflammatory markers are present in participants

  3. The chick embryo as an expanding experimental model for cancer and cardiovascular research.

    PubMed

    Kain, Kristin H; Miller, James W I; Jones-Paris, Celestial R; Thomason, Rebecca T; Lewis, John D; Bader, David M; Barnett, Joey V; Zijlstra, Andries

    2014-02-01

    A long and productive history in biomedical research defines the chick as a model for human biology. Fundamental discoveries, including the description of directional circulation propelled by the heart and the link between oncogenes and the formation of cancer, indicate its utility in cardiac biology and cancer. Despite the more recent arrival of several vertebrate and invertebrate animal models during the last century, the chick embryo remains a commonly used model for vertebrate biology and provides a tractable biological template. With new molecular and genetic tools applied to the avian genome, the chick embryo is accelerating the discovery of normal development and elusive disease processes. Moreover, progress in imaging and chick culture technologies is advancing real-time visualization of dynamic biological events, such as tissue morphogenesis, angiogenesis, and cancer metastasis. A rich background of information, coupled with new technologies and relative ease of maintenance, suggest an expanding utility for the chick embryo in cardiac biology and cancer research. PMID:24357262

  4. Investigating Autonomic Control of the Cardiovascular System: A Battery of Simple Tests

    ERIC Educational Resources Information Center

    Johnson, Christopher D.; Roe, Sean; Tansey, Etain A.

    2013-01-01

    Sympathetic and parasympathetic divisions of the autonomic nervous system constantly control the heart (sympathetic and parasympathetic divisions) and blood vessels (predominantly the sympathetic division) to maintain appropriate blood pressure and organ blood flow over sometimes widely varying conditions. This can be adversely affected by…

  5. The Spontaneously Hypertensive Rat as a Model of Human Cardiovascular Disease: Evidence of Exacerbated Cardiopulmonary Injury and Oxidative Stress from Inhaled Emission Particulate Matter

    Microsoft Academic Search

    Urmila P. Kodavanti; Mette C. Schladweiler; Allen D. Ledbetter; William P. Watkinson; Matthew J. Campen; Darrell W. Winsett; Judy R. Richards; Kay M. Crissman; Gary E. Hatch; Daniel L. Costa

    2000-01-01

    Cardiovascular disease is considered a probable risk factor of particulate matter (PM)-related mortality and morbidity. It was hypothesized that rats with hereditary systemic hypertension and underlying cardiac disease would be more susceptible than healthy normotensive rats to pulmonary injury from inhaled residual oil fly ash (ROFA) PM. Eight spontaneously hypertensive (SH) and eight normotensive Wistar–Kyoto (WKY) rats (12–13 weeks old)

  6. The Earth System Model

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark; Rood, Richard B.; Hildebrand, Peter; Raymond, Carol

    2003-01-01

    The Earth System Model is the natural evolution of current climate models and will be the ultimate embodiment of our geophysical understanding of the planet. These models are constructed from components - atmosphere, ocean, ice, land, chemistry, solid earth, etc. models and merged together through a coupling program which is responsible for the exchange of data from the components. Climate models and future earth system models will have standardized modules, and these standards are now being developed by the ESMF project funded by NASA. The Earth System Model will have a variety of uses beyond climate prediction. The model can be used to build climate data records making it the core of an assimilation system, and it can be used in OSSE experiments to evaluate. The computing and storage requirements for the ESM appear to be daunting. However, the Japanese ES theoretical computing capability is already within 20% of the minimum requirements needed for some 2010 climate model applications. Thus it seems very possible that a focused effort to build an Earth System Model will achieve succcss.

  7. Dysfunction of the ubiquitin-proteasome system in atherosclerotic cardiovascular disease

    PubMed Central

    Wang, Feilong; Lerman, Amir; Herrmann, Joerg

    2015-01-01

    The ubiquitin-proteasome system (UPS) is an integral part of the protein metabolism and protein quality control in eukaryotic cells. It is involved in a number of biological processes of significance for vascular biology and pathology such as oxidative stress, inflammation, foam cell formation, and apoptosis. This review summarizes both indirect and direct lines of evidence for a role of the UPS in atherosclerosis from the initiation to the progression and complication stage and concludes with a future perspective.

  8. Gene Therapy in Large Animal Models of Human Cardiovascular Genetic Disease

    Microsoft Academic Search

    Meg M. Sleeper; Lawrence T. Bish; H. Lee Sweeney

    2009-01-01

    Several naturally occurring animal models for human genetic heart diseases offer an excellent opportunity to evaluate poten- tial novel therapies, including gene therapy. Some of these diseases—especially those that result in a structural defect during development (e.g., patent ductus arteriosus, pulmonic stenosis)—would likely be diffi cult to treat with a therapeutic gene transfer approach. However, the ability to transduce a

  9. Model-Based Systems

    NASA Technical Reports Server (NTRS)

    Frisch, Harold P.

    2007-01-01

    Engineers, who design systems using text specification documents, focus their work upon the completed system to meet Performance, time and budget goals. Consistency and integrity is difficult to maintain within text documents for a single complex system and more difficult to maintain as several systems are combined into higher-level systems, are maintained over decades, and evolve technically and in performance through updates. This system design approach frequently results in major changes during the system integration and test phase, and in time and budget overruns. Engineers who build system specification documents within a model-based systems environment go a step further and aggregate all of the data. They interrelate all of the data to insure consistency and integrity. After the model is constructed, the various system specification documents are prepared, all from the same database. The consistency and integrity of the model is assured, therefore the consistency and integrity of the various specification documents is insured. This article attempts to define model-based systems relative to such an environment. The intent is to expose the complexity of the enabling problem by outlining what is needed, why it is needed and how needs are being addressed by international standards writing teams.

  10. Biomechanics of the cardiovascular system: the aorta as an illustratory example

    PubMed Central

    Kassab, Ghassan S

    2006-01-01

    Biomechanics relates the function of a physiological system to its structure. The objective of biomechanics is to deduce the function of a system from its geometry, material properties and boundary conditions based on the balance laws of mechanics (e.g. conservation of mass, momentum and energy). In the present review, we shall outline the general approach of biomechanics. As this is an enormously broad field, we shall consider a detailed biomechanical analysis of the aorta as an illustration. Specifically, we will consider the geometry and material properties of the aorta in conjunction with appropriate boundary conditions to formulate and solve several well-posed boundary value problems. Among other issues, we shall consider the effect of longitudinal pre-stretch and surrounding tissue on the mechanical status of the vessel wall. The solutions of the boundary value problems predict the presence of mechanical homeostasis in the vessel wall. The implications of mechanical homeostasis on growth, remodelling and postnatal development of the aorta are considered. PMID:17015300

  11. [Peripheral effector mechanism hypothesis on cardiovascular dysfunction after spaceflight].

    PubMed

    Zhang, L F; Yu, Z B; Ma, J; Mao, Q W

    2001-01-01

    In the years of 1990's, we systematically studied the adaptational changes in structure and function of both the heart and the vessels during simulated weightlessness. In our serial work, the tail-suspension rat model was used to simulate the microgravity-induced cephalad shift and redistribution of blood. On the basis of the facts we observed and the more recent advances in space and ground-based studies in 1990's, we put forward a hypothesis to offer a possible explanation for the frequent occurrence of postflight cardiovascular dysfunction. It states that, in addition to the factor of hypovolemia, the microgravity-induced adaptational changes in the structure and function of the two main effectors of the cardiovascular system, i.e., the arterial smooth muscle and the cardiac muscle might be one of the most important mechanisms accounting for postflight cardiovascular dysfunction. PMID:12545770

  12. Cardiovascular consequences of sleep apnea.

    PubMed

    Golbidi, Saeid; Badran, Mohammad; Ayas, Najib; Laher, Ismail

    2012-04-01

    Sleep apnea is a common health concern that is characterized by repetitive episodes of asphyxia. This condition has been linked to serious long-term adverse effects such as hypertension, metabolic dysregulation, and cardiovascular disease. Although the mechanism for the initiation and aggravation of cardiovascular disease has not been fully elucidated, oxidative stress and subsequent endothelial dysfunction play major roles. Animal models, which have the advantage of being free of comorbidities and/or behavioral variables (that commonly occur in humans), allow invasive measurements under well-controlled experimental conditions, and as such are useful tools in the study of the pathophysiological mechanisms of sleep apnea. This review summarizes currently available information on the cardiovascular consequences of sleep apnea and briefly describes common experimental approaches useful to sleep apnea in different animal models. PMID:22048845

  13. Cardiovascular Safety Pharmacology of Sibutramine.

    PubMed

    Yun, Jaesuk; Chung, Eunyong; Choi, Ki Hwan; Cho, Dae Hyun; Song, Yun Jeong; Han, Kyoung Moon; Cha, Hey Jin; Shin, Ji Soon; Seong, Won-Keun; Kim, Young-Hoon; Kim, Hyung Soo

    2015-07-01

    Sibutramine is an anorectic that has been banned since 2010 due to cardiovascular safety issues. However, counterfeit drugs or slimming products that include sibutramine are still available in the market. It has been reported that illegal sibutramine-contained pharmaceutical products induce cardiovascular crisis. However, the mechanism underlying sibutramine-induced cardiovascular adverse effect has not been fully evaluated yet. In this study, we performed cardiovascular safety pharmacology studies of sibutramine systemically using by hERG channel inhibition, action potential duration, and telemetry assays. Sibutramine inhibited hERG channel current of HEK293 cells with an IC50 of 3.92 ?M in patch clamp assay and increased the heart rate and blood pressure (76 ?bpm in heart rate and 51 ?mmHg in blood pressure) in beagle dogs at a dose of 30 mg/kg (per oral), while it shortened action potential duration (at 10 ?M and 30 ?M, resulted in 15% and 29% decreases in APD50, and 9% and 17% decreases in APD90, respectively) in the Purkinje fibers of rabbits and had no effects on the QTc interval in beagle dogs. These results suggest that sibutramine has a considerable adverse effect on the cardiovascular system and may contribute to accurate drug safety regulation. PMID:26157557

  14. Cardiovascular Safety Pharmacology of Sibutramine

    PubMed Central

    Yun, Jaesuk; Chung, Eunyong; Choi, Ki Hwan; Cho, Dae Hyun; Song, Yun Jeong; Han, Kyoung Moon; Cha, Hey Jin; Shin, Ji Soon; Seong, Won-Keun; Kim, Young-Hoon; Kim, Hyung Soo

    2015-01-01

    Sibutramine is an anorectic that has been banned since 2010 due to cardiovascular safety issues. However, counterfeit drugs or slimming products that include sibutramine are still available in the market. It has been reported that illegal sibutramine-contained pharmaceutical products induce cardiovascular crisis. However, the mechanism underlying sibutramine-induced cardiovascular adverse effect has not been fully evaluated yet. In this study, we performed cardiovascular safety pharmacology studies of sibutramine systemically using by hERG channel inhibition, action potential duration, and telemetry assays. Sibutramine inhibited hERG channel current of HEK293 cells with an IC50 of 3.92 ?M in patch clamp assay and increased the heart rate and blood pressure (76 ?bpm in heart rate and 51 ?mmHg in blood pressure) in beagle dogs at a dose of 30 mg/kg (per oral), while it shortened action potential duration (at 10 ?M and 30 ?M, resulted in 15% and 29% decreases in APD50, and 9% and 17% decreases in APD90, respectively) in the Purkinje fibers of rabbits and had no effects on the QTc interval in beagle dogs. These results suggest that sibutramine has a considerable adverse effect on the cardiovascular system and may contribute to accurate drug safety regulation.

  15. euHeart: personalized and integrated cardiac care using patient-specific cardiovascular modelling

    PubMed Central

    Smith, Nic; de Vecchi, Adelaide; McCormick, Matthew; Nordsletten, David; Camara, Oscar; Frangi, Alejandro F.; Delingette, Hervé; Sermesant, Maxime; Relan, Jatin; Ayache, Nicholas; Krueger, Martin W.; Schulze, Walther H. W.; Hose, Rod; Valverde, Israel; Beerbaum, Philipp; Staicu, Cristina; Siebes, Maria; Spaan, Jos; Hunter, Peter; Weese, Juergen; Lehmann, Helko; Chapelle, Dominique; Rezavi, Reza

    2011-01-01

    The loss of cardiac pump function accounts for a significant increase in both mortality and morbidity in Western society, where there is currently a one in four lifetime risk, and costs associated with acute and long-term hospital treatments are accelerating. The significance of cardiac disease has motivated the application of state-of-the-art clinical imaging techniques and functional signal analysis to aid diagnosis and clinical planning. Measurements of cardiac function currently provide high-resolution datasets for characterizing cardiac patients. However, the clinical practice of using population-based metrics derived from separate image or signal-based datasets often indicates contradictory treatments plans owing to inter-individual variability in pathophysiology. To address this issue, the goal of our work, demonstrated in this study through four specific clinical applications, is to integrate multiple types of functional data into a consistent framework using multi-scale computational modelling. PMID:22670205

  16. The extra-pancreatic effects of GLP-1 receptor agonists: a focus on the cardiovascular, gastrointestinal and central nervous systems.

    PubMed

    Seufert, J; Gallwitz, B

    2014-08-01

    The glucagon-like peptide-1 receptor agonists (GLP-1RAs) exenatide, liraglutide and lixisenatide have been shown to improve glycaemic control and beta-cell function with a low risk of hypoglycaemia in people with type 2 diabetes. GLP-1 receptors are also expressed in extra-pancreatic tissues and trial data suggest that GLP-1RAs also have effects beyond their glycaemic actions. Preclinical studies using native GLP-1 or GLP-1RAs provide substantial evidence for cardioprotective effects, while clinical trial data have shown beneficial actions on hypertension and dyslipidaemia in people with type 2 diabetes. Significant weight loss has been reported with GLP-1RAs in both people with type 2 diabetes and obese people without diabetes. GLP-1RAs also slow down gastric emptying, but preclinical data suggest that the main mechanism behind GLP-1RA-induced weight loss is more likely to involve their effects on appetite signalling in the brain. GLP-1RAs have also been shown to exert a neuroprotective role in rodent models of stroke, Alzheimer's disease and Parkinson's disease. These extra-pancreatic effects of GLP-1RAs could provide multi-factorial benefits to people with type 2 diabetes. Potential adverse effects of GLP-1RA treatment are usually manageable but may include gastrointestinal effects, increased heart rate and renal injury. While extensive further research is still required, early data suggest that GLP-1RAs may also have the potential to favourably impact cardiovascular disease, obesity or neurological disorders in people without diabetes in the future. PMID:24373150

  17. Effect of Age on Complexity and Causality of the Cardiovascular Control: Comparison between Model-Based and Model-Free Approaches

    PubMed Central

    Porta, Alberto; Faes, Luca; Bari, Vlasta; Marchi, Andrea; Bassani, Tito; Nollo, Giandomenico; Perseguini, Natália Maria; Milan, Juliana; Minatel, Vinícius; Borghi-Silva, Audrey; Takahashi, Anielle C. M.; Catai, Aparecida M.

    2014-01-01

    The proposed approach evaluates complexity of the cardiovascular control and causality among cardiovascular regulatory mechanisms from spontaneous variability of heart period (HP), systolic arterial pressure (SAP) and respiration (RESP). It relies on construction of a multivariate embedding space, optimization of the embedding dimension and a procedure allowing the selection of the components most suitable to form the multivariate embedding space. Moreover, it allows the comparison between linear model-based (MB) and nonlinear model-free (MF) techniques and between MF approaches exploiting local predictability (LP) and conditional entropy (CE). The framework was applied to study age-related modifications of complexity and causality in healthy humans in supine resting (REST) and during standing (STAND). We found that: 1) MF approaches are more efficient than the MB method when nonlinear components are present, while the reverse situation holds in presence of high dimensional embedding spaces; 2) the CE method is the least powerful in detecting age-related trends; 3) the association of HP complexity on age suggests an impairment of cardiac regulation and response to STAND; 4) the relation of SAP complexity on age indicates a gradual increase of sympathetic activity and a reduced responsiveness of vasomotor control to STAND; 5) the association from SAP to HP on age during STAND reveals a progressive inefficiency of baroreflex; 6) the reduced connection from HP to SAP with age might be linked to the progressive exploitation of Frank-Starling mechanism at REST and to the progressive increase of peripheral resistances during STAND; 7) at REST the diminished association from RESP to HP with age suggests a vagal withdrawal and a gradual uncoupling between respiratory activity and heart; 8) the weakened connection from RESP to SAP with age might be related to the progressive increase of left ventricular thickness and vascular stiffness and to the gradual decrease of respiratory sinus arrhythmia. PMID:24586796

  18. Pretransplant cardiovascular evaluation and posttransplant cardiovascular risk

    Microsoft Academic Search

    James B Young; Hans-Hellmut Neumayer; Robert D Gordon

    2010-01-01

    Modern immunosuppression has expanded access to kidney transplantation by limiting the risk of rejection. However, cardiovascular disease (CVD) remains the principal cause of death with a functioning graft, threatening the long-term survival of transplant recipients. The article reviews the leading risk factors for cardiovascular morbidity both before and after kidney transplantation. Evidence linking poor renal function to CVD is discussed.

  19. Adaptive responses of the cardiovascular system to prolonged spaceflight conditions: assessment with Holter monitoring

    NASA Technical Reports Server (NTRS)

    Baevsky, R. M.; Bennett, B. S.; Bungo, M. W.; Charles, J. B.; Goldberger, A. L.; Nikulina, G. A.

    1997-01-01

    This article presents selected findings obtained with Holter monitoring from two crew members of the expedition, performed during a 175-day space mission on board orbital space station "MIR." Using mathematical processing of daily cardiointervals files, 5-minute sections of records were analyzed consecutively. Then, the average daily values of indices, the average-per-every-eight-hours values (morning, evening, night) and mean values per hour were computed. The results of analysis showed that prolonged exposure of man to microgravity conditions leads to important functional alteration in human neuroautonomic regulatory mechanisms. Both crew members had significant increase of heart rate, the rise of stress index, the decrease in power of the spectrum in the range of respiratory sinus arrhythmia. These marked signs of activation of the sympathetic section of the vegetative nervous system showed individual variations. The analysis of the daily collection of cardiointervals with Holter monitoring allows us to understand and forecast the functional feasibilities of the human organism under a variety of stress conditions associated with acute and chronic microgravity exposure.

  20. Thyroid Hormones and Antioxidant Systems: Focus on Oxidative Stress in Cardiovascular and Pulmonary Diseases

    PubMed Central

    Mancini, Antonio; Raimondo, Sebastiano; Di Segni, Chantal; Persano, Mariasara; Gadotti, Giovanni; Silvestrini, Andrea; Festa, Roberto; Tiano, Luca; Pontecorvi, Alfredo; Meucci, Elisabetta

    2013-01-01

    In previous works we demonstrated an inverse correlation between plasma Coenzyme Q10 (CoQ10) and thyroid hormones; in fact, CoQ10 levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ10 is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q10. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions. PMID:24351864

  1. Intermedin (adrenomedullin-2): a novel counter-regulatory peptide in the cardiovascular and renal systems

    PubMed Central

    Bell, D; McDermott, B J

    2008-01-01

    Intermedin (IMD) is a novel peptide related to calcitonin gene-related peptide (CGRP) and adrenomedullin (AM). Proteolytic processing of a larger precursor yields a series of biologically active C-terminal fragments, IMD1–53, IMD1–47 and IMD8–47. IMD shares a family of receptors with AM and CGRP composed of a calcitonin-receptor like receptor (CALCRL) associated with one of three receptor activity modifying proteins (RAMP). Compared to CGRP, IMD is less potent at CGRP1 receptors but more potent at AM1 receptors and AM2 receptors; compared to AM, IMD is more potent at CGRP1 receptors but less potent at AM1 and AM2 receptors. The cellular and tissue distribution of IMD overlaps in some aspects with that of CGRP and AM but is distinct from both. IMD is present in neonatal but absent or expressed sparsely, in adult heart and vasculature and present at low levels in plasma. The prominent localization of IMD in hypothalamus and pituitary and in kidney is consistent with a physiological role in the central and peripheral regulation of the circulation and water-electrolyte homeostasis. IMD is a potent systemic and pulmonary vasodilator, influences regional blood flow and augments cardiac contractility. IMD protects myocardium from the deleterious effects of oxidative stress associated with ischaemia-reperfusion injury and exerts an anti-growth effect directly on cardiomyocytes to oppose the influence of hypertrophic stimuli. The robust increase in expression of the peptide in hypertrophied and ischaemic myocardium indicates an important protective role for IMD as an endogenous counter-regulatory peptide in the heart. PMID:17965749

  2. Omega-3 fatty acids: role in metabolism and cardiovascular disease.

    PubMed

    Gerber, Philipp A; Gouni-Berthold, Ioanna; Berneis, Kaspar

    2013-01-01

    The inverse association of cardiovascular risk with intake of omega-3 polyunsaturated fatty acids was suspected early in populations that are known to have a high consumption of fish and fish oil. Subsequent cohort studies confirmed such associations in other populations. Further evidence of possible beneficial effects on metabolism and cardiovascular health was provided by many studies that were able to show specific mechanisms that may underlie these observations. These include improvement of the function of tissues involved in the alterations occurring during the development of obesity and the metabolic syndrome, as adipose tissue, the liver and skeletal muscle. Direct action on the cardiovascular system was not only shown regarding vascular function and the formation of atherosclerotic plaques, but also by providing antiarrhythmic effects on the heart. Data on these effects come from in vitro as well as in vivo studies that were conducted in animal models of disease, in healthy humans and in humans suffering from cardiovascular disease. To define prophylactic as well as treatment options in primary and secondary prevention, large clinical trial assessed the effect of omega-3 polyunsaturated fatty acids on end points as cardiovascular morbidity and mortality. However, so far these trials provided ambiguous data that do allow recommendations regarding the use of omega-3 polyunsaturated fatty acids in higher dosages and beyond the dietary advice of regular fish intake only in few clinical situations, such as severe hypertriglyceridemia. PMID:23317405

  3. Multiscale Cloud System Modeling

    NASA Technical Reports Server (NTRS)

    Tao, Wei-Kuo; Moncrieff, Mitchell W.

    2009-01-01

    The central theme of this paper is to describe how cloud system resolving models (CRMs) of grid spacing approximately 1 km have been applied to various important problems in atmospheric science across a wide range of spatial and temporal scales and how these applications relate to other modeling approaches. A long-standing problem concerns the representation of organized precipitating convective cloud systems in weather and climate models. Since CRMs resolve the mesoscale to large scales of motion (i.e., 10 km to global) they explicitly address the cloud system problem. By explicitly representing organized convection, CRMs bypass restrictive assumptions associated with convective parameterization such as the scale gap between cumulus and large-scale motion. Dynamical models provide insight into the physical mechanisms involved with scale interaction and convective organization. Multiscale CRMs simulate convective cloud systems in computational domains up to global and have been applied in place of contemporary convective parameterizations in global models. Multiscale CRMs pose a new challenge for model validation, which is met in an integrated approach involving CRMs, operational prediction systems, observational measurements, and dynamical models in a new international project: the Year of Tropical Convection, which has an emphasis on organized tropical convection and its global effects.

  4. Homocysteine and cardiovascular disease

    Microsoft Academic Search

    Arduino A Mangoni; Stephen H. D Jackson

    2002-01-01

    Hyperhomocysteinemia is an independent risk factor for cardiovascular disease. Despite the well-known effectiveness of vitamin supplementation in reducing homocysteine levels, it is not known whether lowering of homocysteine levels is associated with a reduction in cardiovascular morbidity and mortality. The aim of this review is to discuss the epidemiologic evidence about the relation between homocysteine and cardiovascular disease, the pathophysiologic

  5. Modeling adaptive biological systems.

    PubMed

    Bagley, R J; Farmer, J D; Kauffman, S A; Packard, N H; Perelson, A S; Stadnyk, I M

    1989-01-01

    During the evolution of many systems found in nature, both the system composition and the interactions between components will vary. Equating the dimension with the number of different components, a system which adds or deletes components belongs to a class of dynamical systems with a finite dimensional phase space of variable dimension. We present two models of biochemical systems with a variable phase space, a model of autocatalytic reaction networks in the prebiotic soup and a model of the idiotypic network of the immune system. Each model contains characteristic meta-dynamical rules for constructing equations of motion from component properties. The simulation of each model occurs on two levels. On one level, the equations of motion are integrated to determine the state of each component. On a second level, algorithms which approximate physical processes in the real system are employed to change the equations of motion. Models with meta-dynamical rules possess several advantages for the study of evolving systems. First, there are no explicit fitness functions to determine how the components of the model rank in terms of survivability. The success of any component is a function of its relationship to the rest of the system. A second advantage is that since the phase space representation of the system is always finite but continually changing, we can explore a potentially infinite phase space which would otherwise be inaccessible with finite computer resources. Third, the enlarged capacity of systems with meta-dynamics for variation allows us to conduct true evolution experiments. The modeling methods presented here can be applied to many real biological systems. In the two studies we present, we are investigating two apparent properties of adaptive networks. With the simulation of the prebiotic soup, we are most interested in how a chemical reaction network might emerge from an initial state of relative disorder. With the study of the immune system, we study the self-regulation of the network including its ability to distinguish between species which are part of the network and those which are not. PMID:2627562

  6. Modeling Systemic Dependencies through

    E-print Network

    California at Los Angeles, University of

    Modeling Systemic Dependencies through Attack Surface Analysis! Eric Osterweil! Danny Mc dependencies and attack surfaces?! #12;3 !Verisign Public ! What networked systems do I need to tweet to 50're often only discovered reactively! · We turn to attack surface ::= what could feasibly be used to attack

  7. Systems Theory and Modeling

    NSDL National Science Digital Library

    Division of Science and Environmental Policy at California State University, Monterey Bay

    From the website: 'This site is for teachers, students, and anyone else who would like a very brief, general introduction to systems thinking and systems modeling. It was written primarily as a teaching resource for college and high school instructors who are short on time, but dedicated to helping students frame and focus their thinking on environmental issues or other complicated, interdisciplinary topics. The site assumes no prior knowledge of systems theory or modeling techniques and covers only the basics, but it includes references to more advanced information for anyone who wants to study this subject in greater depth.'

  8. Short-term use of telmisartan attenuates oxidation and improves Prdx2 expression more than antioxidant ?-blockers in the cardiovascular systems of spontaneously hypertensive rats.

    PubMed

    Yoo, Sae Mi; Choi, Sung Hyun; Jung, Monica Dha Yea; Lim, Sung Cil; Baek, Sang Hong

    2015-02-01

    Reactive oxygen species (ROS) and antioxidant enzymes are required to maintain homeostasis. The loss of this balance can cause excessive ROS production and damage to the cardiovascular tissues. Angiotensin II receptor blockers (ARBs) and ?-blockers with antioxidant effects may inhibit ROS in the cardiovascular system. In this study, we directly compared the effects of ARBs and ?-blockers with antioxidant properties on cardiovascular protection and the regulation of endothelial progenitor cell (EPC) numbers in the setting of oxidative stress in hypertensive rats. To compare the effects of the drugs, animals were divided into the following groups: Wistar-Kyoto rats (WKY), untreated spontaneously hypertensive rats (SHR) and SHR treated with tempol (TEMP, 5?mg?kg(-1) per day), trichlorothiazide (TCTZ, 1.6?mg?kg(-1) per day), atenolol (25?mg?kg(-1) per day), nebivolol (NEBL, 5?mg?kg(-1) per day), carvedilol (CVDL, 30?mg?kg(-1) per day) or telmisartan (TERT, 5?mg?kg(-1) per day). Following 2 weeks of treatment, blood pressures (BPs) and aortic wall thicknesses were similarly reduced in each antihypertensive drug-treated group. Superoxide anion and malondialdehyde levels were significantly reduced following treatment with NEBL, CVDL and TERT. Additionally, the expression levels of NADPH oxidase subunits were also reduced in the TERT-, CVDL- and NEBL-treated groups. Furthermore, these drugs improved both EPC numbers and the expression levels of peroxiredoxin 2 (Prdx2), an antioxidant enzyme, in the heart and kidneys but not the aorta. Cardiac Prdx2 expression, in particular, was markedly improved by TERT, NEBL and CVDL treatment, and renal Prdx2 expression was enhanced by TEMP. Our data indicate that short-term treatment with TERT may have more beneficial effects on cardiovascular protection, EPC number improvements and Prdx2 expression compared with CVDL and NEBL. In conclusion, TERT may positively modulate the balance between oxidative stress and antioxidant properties and demonstrate capabilities beyond its BP-lowering effects. PMID:25319599

  9. Hypothetical exposure limits for oil-based metalworking fluids and cardiovascular mortality in a cohort of autoworkers: structural accelerated failure time models in a public health framework.

    PubMed

    Picciotto, Sally; Peters, Annette; Eisen, Ellen A

    2015-04-15

    Occupational exposure to aerosolized particles of oil-based metalworking fluid was recently linked to deaths from ischemic heart disease. The current recommended exposure limits might be insufficient. Studying cardiovascular mortality is challenging because symptoms can induce sicker workers to reduce their exposure, causing healthy-worker survivor bias. G-estimation of accelerated failure time models reduces this bias and permits comparison of multiple exposure interventions. Michigan autoworkers from the United AutoWorkers-General Motors cohort (n = 38,666) were followed from 1941 through 1994. Separate binary variables indicated whether annual exposure exceeded a series of potential limits. Separate g-estimation analyses for each limit yielded the total number of life-years that could have been saved among persons who died from specific cardiovascular causes by enforcing that exposure limit. Banning oil-based fluids would have saved an estimated 4,003 (95% confidence interval: 2,200, 5,807) life-years among those who died of ischemic heart disease. Estimates for cardiovascular disease overall, acute myocardial infarction, and cerebrovascular disease were 3,500 (95% confidence interval: 1,350, 5,651), 2,932 (95% confidence interval: 1,587, 4,277), and 917 (95% confidence interval: -80, 1,913) life-years, respectively. A limit of 0.01 mg/m(3) would have had a similar impact on cerebrovascular disease but one only half as great on ischemic heart disease. Analyses suggest that limiting exposure to metalworking fluids could have saved many life-years lost to cardiovascular diseases in this cohort. PMID:25816818

  10. Hypothetical Exposure Limits for Oil-Based Metalworking Fluids and Cardiovascular Mortality in a Cohort of Autoworkers: Structural Accelerated Failure Time Models in a Public Health Framework

    PubMed Central

    Picciotto, Sally; Peters, Annette; Eisen, Ellen A.

    2015-01-01

    Occupational exposure to aerosolized particles of oil-based metalworking fluid was recently linked to deaths from ischemic heart disease. The current recommended exposure limits might be insufficient. Studying cardiovascular mortality is challenging because symptoms can induce sicker workers to reduce their exposure, causing healthy-worker survivor bias. G-estimation of accelerated failure time models reduces this bias and permits comparison of multiple exposure interventions. Michigan autoworkers from the United AutoWorkers–General Motors cohort (n = 38,666) were followed from 1941 through 1994. Separate binary variables indicated whether annual exposure exceeded a series of potential limits. Separate g-estimation analyses for each limit yielded the total number of life-years that could have been saved among persons who died from specific cardiovascular causes by enforcing that exposure limit. Banning oil-based fluids would have saved an estimated 4,003 (95% confidence interval: 2,200, 5,807) life-years among those who died of ischemic heart disease. Estimates for cardiovascular disease overall, acute myocardial infarction, and cerebrovascular disease were 3,500 (95% confidence interval: 1,350, 5,651), 2,932 (95% confidence interval: 1,587, 4,277), and 917 (95% confidence interval: ?80, 1,913) life-years, respectively. A limit of 0.01 mg/m3 would have had a similar impact on cerebrovascular disease but one only half as great on ischemic heart disease. Analyses suggest that limiting exposure to metalworking fluids could have saved many life-years lost to cardiovascular diseases in this cohort. PMID:25816818

  11. Undergraduates Understanding of Cardiovascular Phenomena

    NSDL National Science Digital Library

    PhD Joel A. Michael (Rush Medical College Department of Molecular Biophysics and Physiology)

    2002-06-01

    Undergraduates students in 12 courses at 8 different institutions were surveyed to determine the prevalence of 13 different misconceptions (conceptual difficulties) about cardiovascular function. The prevalence of these misconceptions ranged from 20 to 81% and, for each misconception, was consistent across the different student populations. We also obtained explanations for the studentsÂ? answers either as free responses or with follow-up multiple-choice questions. These results suggest that students have a number of underlying conceptual difficulties about cardiovascular phenomena. One possible source of some misconceptions is the studentsÂ? inability to apply simple general models to specific cardiovascular phenomena. Some implications of these results for teachers of physiology are discussed.

  12. ESMDIS: Earth System Model Data Information System

    Microsoft Academic Search

    Yuechen Chi; Carlos R. Mechoso; Michael Stonebraker; Keith Sklower; Richard Troy; Richard R. Muntz; Edmond Mesrobian

    1997-01-01

    The goal of the development of the Earth System Model Data Information System (ESMDIS) are to provide Earth scientists with: 1) an output management system of Earth System Model (ESM) to browse the metadata and retrieve a desired subset of ESM output; 2) an analysis system of ESM output and other related datasets; 3) an automated pipelining system for ESM

  13. Genetic Analysis of the Cardiac Methylome at Single Nucleotide Resolution in a Model of Human Cardiovascular Disease

    PubMed Central

    Adamowicz-Brice, Martyna; Collins, Melissa J.; Gellert, Pascal; Maratou, Klio; Srivastava, Prashant K.; Rotival, Maxime; Butt, Shahena; Game, Laurence; Atanur, Santosh S.; Silver, Nicholas; Norsworthy, Penny J.; Langley, Sarah R.; Petretto, Enrico; Pravenec, Michal; Aitman, Timothy J.

    2014-01-01

    Epigenetic marks such as cytosine methylation are important determinants of cellular and whole-body phenotypes. However, the extent of, and reasons for inter-individual differences in cytosine methylation, and their association with phenotypic variation are poorly characterised. Here we present the first genome-wide study of cytosine methylation at single-nucleotide resolution in an animal model of human disease. We used whole-genome bisulfite sequencing in the spontaneously hypertensive rat (SHR), a model of cardiovascular disease, and the Brown Norway (BN) control strain, to define the genetic architecture of cytosine methylation in the mammalian heart and to test for association between methylation and pathophysiological phenotypes. Analysis of 10.6 million CpG dinucleotides identified 77,088 CpGs that were differentially methylated between the strains. In F1 hybrids we found 38,152 CpGs showing allele-specific methylation and 145 regions with parent-of-origin effects on methylation. Cis-linkage explained almost 60% of inter-strain variation in methylation at a subset of loci tested for linkage in a panel of recombinant inbred (RI) strains. Methylation analysis in isolated cardiomyocytes showed that in the majority of cases methylation differences in cardiomyocytes and non-cardiomyocytes were strain-dependent, confirming a strong genetic component for cytosine methylation. We observed preferential nucleotide usage associated with increased and decreased methylation that is remarkably conserved across species, suggesting a common mechanism for germline control of inter-individual variation in CpG methylation. In the RI strain panel, we found significant correlation of CpG methylation and levels of serum chromogranin B (CgB), a proposed biomarker of heart failure, which is evidence for a link between germline DNA sequence variation, CpG methylation differences and pathophysiological phenotypes in the SHR strain. Together, these results will stimulate further investigation of the molecular basis of locally regulated variation in CpG methylation and provide a starting point for understanding the relationship between the genetic control of CpG methylation and disease phenotypes. PMID:25474312

  14. Distribution of cardiovascular disease and retinopathy in patients with type 2 diabetes according to different classification systems for chronic kidney disease: a cross-sectional analysis of the renal insufficiency and cardiovascular events (RIACE) Italian multicenter study

    PubMed Central

    2014-01-01

    Background The National Kidney Foundation’s Kidney Disease Outcomes Quality Initiative (NKF’s KDOQI) staging system for chronic kidney disease (CKD) is based primarily on estimated GFR (eGFR). This study aimed at assessing whether reclassification of subjects with type 2 diabetes using two recent classifications based on both eGFR and albuminuria, the Alberta Kidney Disease Network (AKDN) and the Kidney Disease: Improving Global Outcomes (KDIGO), provides a better definition of burden from cardiovascular disease (CVD) and diabetic retinopathy (DR) than the NKF’s KDOQI classification. Methods This is a cross-sectional analysis of patients with type 2 diabetes (n?=?15,773) from the Renal Insufficiency And Cardiovascular Events Italian Multicenter Study, consecutively visiting 19 Diabetes Clinics throughout Italy in years 2007-2008. Exclusion criteria were dialysis or renal transplantation. CKD was defined based on eGFR, as calculated from serum creatinine by the simplified Modification of Diet in Renal Disease Study equation, and albuminuria, as measured by immunonephelometry or immunoturbidimetry. DR was assessed by dilated fundoscopy. Prevalent CVD, total and by vascular bed, was assessed from medical history by recording previous documented major acute events. Results Though prevalence of complications increased with increasing CKD severity with all three classifications, it differed significantly between NKF’s KDOQI stages and AKDN or KDIGO risk categories. The AKDN and KDIGO systems resulted in appropriate reclassification of uncomplicated patients in the lowest risk categories and a more graded independent association with CVD and DR than the NKF’s KDOQI classification. However, CVD, but not DR prevalence was higher in the lowest risk categories of the new classifications than in the lowest stages of the NKF’s KDOQI, due to the inclusion of subjects with reduced eGFR without albuminuria. CVD prevalence differed also among eGFR and albuminuria categories grouped into AKDN and KDIGO risk category 1 and moderate, respectively, and to a lesser extent into higher risk categories. Conclusions Though the new systems perform better than the NKF’s KDOQI in grading complications and identifying diabetic subjects without complications, they might underestimate CVD burden in patients assigned to lower risk categories and should be tested in large prospective studies. Trial registration ClinicalTrials.gov; NCT00715481 PMID:24624891

  15. Cardiovascular Disease, Mitochondria, and Traditional Chinese Medicine

    PubMed Central

    Wang, Jie; Guo, Li-li; Xiong, Xing-jiang; Fan, Xun

    2015-01-01

    Recent studies demonstrated that mitochondria play an important role in the cardiovascular system and mutations of mitochondrial DNA affect coronary artery disease, resulting in hypertension, atherosclerosis, and cardiomyopathy. Traditional Chinese medicine (TCM) has been used for thousands of years to treat cardiovascular disease, but it is not yet clear how TCM affects mitochondrial function. By reviewing the interactions between the cardiovascular system, mitochondrial DNA, and TCM, we show that cardiovascular disease is negatively affected by mutations in mitochondrial DNA and that TCM can be used to treat cardiovascular disease by regulating the structure and function of mitochondria via increases in mitochondrial electron transport and oxidative phosphorylation, modulation of mitochondrial-mediated apoptosis, and decreases in mitochondrial ROS. However further research is still required to identify the mechanism by which TCM affects CVD and modifies mitochondrial DNA.

  16. Assistant, Associate & Full Professor Division of Cardiovascular Medicine

    E-print Network

    Quake, Stephen R.

    of cardiovascular disease. The applicant will have M.D., Ph.D., or M.D. /Ph.D degrees and will be appointed of the risk for cardiovascular disease, including the use of novel animal models and the use of modern humanAssistant, Associate & Full Professor Division of Cardiovascular Medicine Department of Medicine

  17. Down Syndrome: A Cardiovascular Perspective

    ERIC Educational Resources Information Center

    Vis, J. C.; Duffels, M. G. J.; Winter, M. M.; Weijerman, M. E.; Cobben, J. M.; Huisman, S. A.; Mulder, B. J. M.

    2009-01-01

    This review focuses on the heart and vascular system in patients with Down syndrome. A clear knowledge on the wide spectrum of various abnormalities associated with this syndrome is essential for skillful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and…

  18. Optical systems integrated modeling

    NASA Technical Reports Server (NTRS)

    Shannon, Robert R.; Laskin, Robert A.; Brewer, SI; Burrows, Chris; Epps, Harlan; Illingworth, Garth; Korsch, Dietrich; Levine, B. Martin; Mahajan, Vini; Rimmer, Chuck

    1992-01-01

    An integrated modeling capability that provides the tools by which entire optical systems and instruments can be simulated and optimized is a key technology development, applicable to all mission classes, especially astrophysics. Many of the future missions require optical systems that are physically much larger than anything flown before and yet must retain the characteristic sub-micron diffraction limited wavefront accuracy of their smaller precursors. It is no longer feasible to follow the path of 'cut and test' development; the sheer scale of these systems precludes many of the older techniques that rely upon ground evaluation of full size engineering units. The ability to accurately model (by computer) and optimize the entire flight system's integrated structural, thermal, and dynamic characteristics is essential. Two distinct integrated modeling capabilities are required. These are an initial design capability and a detailed design and optimization system. The content of an initial design package is shown. It would be a modular, workstation based code which allows preliminary integrated system analysis and trade studies to be carried out quickly by a single engineer or a small design team. A simple concept for a detailed design and optimization system is shown. This is a linkage of interface architecture that allows efficient interchange of information between existing large specialized optical, control, thermal, and structural design codes. The computing environment would be a network of large mainframe machines and its users would be project level design teams. More advanced concepts for detailed design systems would support interaction between modules and automated optimization of the entire system. Technology assessment and development plans for integrated package for initial design, interface development for detailed optimization, validation, and modeling research are presented.

  19. Assessment of distribution and evolution of Mechanical dyssynchrony in a porcine model of myocardial infarction by cardiovascular magnetic resonance

    PubMed Central

    2012-01-01

    Background We sought to investigate the relationship between infarct and dyssynchrony post- myocardial infarct (MI), in a porcine model. Mechanical dyssynchrony post-MI is associated with left ventricular (LV) remodeling and increased mortality. Methods Cine, gadolinium-contrast, and tagged cardiovascular magnetic resonance (CMR) were performed pre-MI, 9 ± 2 days (early post-MI), and 33 ± 10 days (late post-MI) post-MI in 6 pigs to characterize cardiac morphology, location and extent of MI, and regional mechanics. LV mechanics were assessed by circumferential strain (eC). Electro-anatomic mapping (EAM) was performed within 24 hrs of CMR and prior to sacrifice. Results Mean infarct size was 21 ± 4% of LV volume with evidence of post-MI remodeling. Global eC significantly decreased post MI (-27 ± 1.6% vs. -18 ± 2.5% (early) and -17 ± 2.7% (late), p < 0.0001) with no significant change in peri-MI and MI segments between early and late time-points. Time to peak strain (TTP) was significantly longer in MI, compared to normal and peri-MI segments, both early (440 ± 40 ms vs. 329 ± 40 ms and 332 ± 36 ms, respectively; p = 0.0002) and late post-MI (442 ± 63 ms vs. 321 ± 40 ms and 355 ± 61 ms, respectively; p = 0.012). The standard deviation of TTP in 16 segments (SD16) significantly increased post-MI: 28 ± 7 ms to 50 ± 10 ms (early, p = 0.012) to 54 ± 19 ms (late, p = 0.004), with no change between early and late post-MI time-points (p = 0.56). TTP was not related to reduction of segmental contractility. EAM revealed late electrical activation and greatly diminished conduction velocity in the infarct (5.7 ± 2.4 cm/s), when compared to peri-infarct (18.7 ± 10.3 cm/s) and remote myocardium (39 ± 20.5 cm/s). Conclusions Mechanical dyssynchrony occurs early after MI and is the result of delayed electrical and mechanical activation in the infarct. PMID:22226320

  20. Modeling the earth system

    SciTech Connect

    Ojima, D. [ed.

    1992-12-31

    The 1990 Global Change Institute (GCI) on Earth System Modeling is the third of a series organized by the Office for Interdisciplinary Earth Studies to look in depth at particular issues critical to developing a better understanding of the earth system. The 1990 GCI on Earth System Modeling was organized around three themes: defining critical gaps in the knowledge of the earth system, developing simplified working models, and validating comprehensive system models. This book is divided into three sections that reflect these themes. Each section begins with a set of background papers offering a brief tutorial on the subject, followed by working group reports developed during the institute. These reports summarize the joint ideas and recommendations of the participants and bring to bear the interdisciplinary perspective that imbued the institute. Since the conclusion of the 1990 Global Change Institute, research programs, nationally and internationally, have moved forward to implement a number of the recommendations made at the institute, and many of the participants have maintained collegial interactions to develop research projects addressing the needs identified during the two weeks in Snowmass.

  1. Cellular mechanisms underlying the cardiovascular actions of oestrogens.

    PubMed

    Ling, Shanhong; Komesaroff, Paul; Sudhir, Krishnankutty

    2006-08-01

    Although pre-menopausal women enjoy relative cardiovascular protection, hormone (oestrogen+/-progestin)-replacement therapy has not shown cardiovascular benefits in post-menopausal women, suggesting that the effects of oestrogens on the cardiovascular system are much more complex than previously expected. Endothelial cells, smooth muscle cells, cardiac myocytes and fibroblasts, the cellular components of blood vessels and the heart, play important roles in cardiovascular health and disease. During the development and progression of cardiovascular disease, changes occur both in the structure and function of these cells, resulting in a wide range of abnormalities, which affect growth, death and physiological function. These cells contain functional oestrogen receptors and are targets for oestrogen action. This review focuses on recent studies on the effects of oestrogen on cardiovascular cell function. Oestrogens, particularly 17beta-oestradiol, exert multiple effects on cardiovascular cells, and these effects may contribute to the gender-associated protection against cardiovascular diseases. PMID:16831130

  2. Rationale for the Use of Anticholinergic Agents in Overactive Bladder With Regard to Central Nervous System and Cardiovascular System Side Effects

    PubMed Central

    Onal, Bulent

    2013-01-01

    Purpose Central nervous system (CNS) and cardiovascular system (CVS) side effects of anticholinergic agents used to treat overactive bladder (OAB) are underreported. Hence, this review aimed to focus on the mechanisms of CNS and CVS side effects of anticholinergic drugs used in OAB treatment, which may help urologists in planning the rationale for OAB treatment. Materials and Methods PubMed/MEDLINE was searched for the key words "OAB," "anticholinergics," "muscarinic receptor selectivity," "blood-brain barrier," "CNS," and "CVS side effects." Additional relevant literature was determined by examining the reference lists of articles identified through the search. Results CNS and CVS side effects, pharmacodynamic and pharmacokinetic properties, the metabolism of these drugs, and the clinical implications for their use in OAB are presented and discussed in this review. Conclusions Trospium, 5-hydroxymethyl tolterodine, darifenacin, and solifenacin seem to have favorable pharmacodynamic and pharmacokinetic properties with regard to CNS side effects, whereas the pharmacodynamic features of darifenacin, solifenacin, and oxybutynin appear to have an advantage over the other anticholinergic agents (tolterodine, fesoterodine, propiverine, and trospium) with regard to CVS side effects. To determine the real-life situation, head-to-head studies focusing especially on CNS and CVS side effects of OAB anticholinergic agents are urgently needed. PMID:24363860

  3. Role of carbon monxide in cardiovascular function

    PubMed Central

    Durante, William; Johnson, Fruzsina K; Johnson, Robert A

    2006-01-01

    Carbon monoxide (CO) is an endogenously derived gas formed from the breakdown of heme by the enzyme heme oxygenase. Although long considered an insignificant and potentially toxic waste product of heme catabolism, CO is now recognized as a key signaling molecule that regulates numerous cardiovascular functions. Interestingly, alterations in CO synthesis are associated with many cardiovascular disorders, including atherosclerosis, septic shock, hypertension, metabolic syndrome, and ischemia-reperfusion injury. Significantly, restoration of physiologic CO levels exerts a beneficial effect in many of these settings, suggesting a crucial role for CO in maintaining cardiovascular homeostasis. In this review, we outline the actions of CO in the cardiovascular system and highlight this gas as a potential therapeutic target in treating a multitude of cardiovascular disorders. PMID:16989727

  4. Security system throughput modeling

    Microsoft Academic Search

    K. Leone

    2002-01-01

    One of the keys to integrating 100% checked bag screening into airports is identifying realistic throughput rates of various explosive detection system (EDS) machines available to Transportation Security Administration (TSA) planners. This study discusses some of the issues associated with the implementation of EDS equipment and performs an analysis on the throughput of the equipment using modeling and discrete event

  5. The Challenge of Cardiovascular Diseases and Diabetes to Public Health: A Study Based on Qualitative Systemic Approach

    PubMed Central

    Carvalho, Marilia Sá; Coeli, Claudia Medina; Chor, Dóra; Pinheiro, Rejane Sobrino; da Fonseca, Maria de Jesus Mendes; de Sá Carvalho, Luiz Carlos

    2015-01-01

    The most common modeling approaches to understanding incidence, prevalence and control of chronic diseases in populations, such as statistical regression models, are limited when it comes to dealing with the complexity of those problems. Those complex adaptive systems have characteristics such as emerging properties, self-organization and feedbacks, which structure the system stability and resistance to changes. Recently, system science approaches have been proposed to deal with the range, complexity, and multifactor nature of those public health problems. In this paper we applied a multilevel systemic approach to create an integrated, coherent, and increasingly precise conceptual framework, capable of aggregating different partial or specialized studies, based on the challenges of the Longitudinal Study of Adult Health – ELSA-Brasil. The failure to control blood pressure found in several of the study's subjects was discussed, based on the proposed model, analyzing different loops, time lags, and feedback that influence this outcome in a population with high educational level, with reasonably good health services access. We were able to identify the internal circularities and cycles that generate the system’s resistance to change. We believe that this study can contribute to propose some new possibilities of the research agenda and to the discussion of integrated actions in the field of public health. PMID:26171854

  6. Cardiovascular reactivity, stress, and physical activity

    PubMed Central

    Huang, Chun-Jung; Webb, Heather E.; Zourdos, Michael C.; Acevedo, Edmund O.

    2013-01-01

    Psychological stress has been proposed as a major contributor to the progression of cardiovascular disease (CVD). Acute mental stress can activate the sympathetic-adrenal-medullary (SAM) axis, eliciting the release of catecholamines (NE and EPI) resulting in the elevation of heart rate (HR) and blood pressure (BP). Combined stress (psychological and physical) can exacerbate these cardiovascular responses, which may partially contribute to the elevated risk of CVD and increased proportionate mortality risks experienced by some occupations (e.g., firefighting and law enforcement). Studies have supported the benefits of physical activity on physiological and psychological health, including the cardiovascular response to acute stress. Aerobically trained individuals exhibit lower sympathetic nervous system (e.g., HR) reactivity and enhanced cardiovascular efficiency (e.g., lower vascular reactivity and decreased recovery time) in response to physical and/or psychological stress. In addition, resistance training has been demonstrated to attenuate cardiovascular responses and improve mental health. This review will examine stress-induced cardiovascular reactivity and plausible explanations for how exercise training and physical fitness (aerobic and resistance exercise) can attenuate cardiovascular responses to stress. This enhanced functionality may facilitate a reduction in the incidence of stroke and myocardial infarction. Finally, this review will also address the interaction of obesity and physical activity on cardiovascular reactivity and CVD. PMID:24223557

  7. Molecular mechanisms and clinical applications of ginseng root for cardiovascular disease.

    PubMed

    Zhou, Wei; Chai, Hong; Lin, Peter H; Lumsden, Alan B; Yao, Qizhi; Chen, Changyi Johnny

    2004-08-01

    Ginseng root is used extensively in traditional Chinese medicine for its alleged tonic effect and possible curative and restorative properties. There are increasing evidences in the literature on the potential role of ginseng in treating cardiovascular diseases. We herein examine the history of ginseng usage and review the current literature on a myriad pharmacological function of ginseng on the cardiovascular system. From the published studies involving cell cultures and animal models, ginseng is shown to have potential benefits on the cardiovascular system through diverse mechanisms, including antioxidant, modifying vasomotor function, reducing platelet adhesion, influencing ion channels, altering autonomic neurotransmitters release, improving lipid profiles, and involving in glucose metabolism and glycemic control. In addition, the relevant clinical trials regarding the effects of ginseng on the cardiovascular disease are summarized, particularly in managing hypertension and improving cardiovascular function. Finally, the controversies in the literature and the possible adverse interactions between ginseng and other drugs are discussed. This review underscores the potential benefit effects of ginseng on cardiovascular diseases, highlights the gaps in our current research, and emphasizes the necessity for more rigorous systemic investigation. PMID:15278009

  8. Lipoprotein metabolism indicators improve cardiovascular risk prediction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Cardiovascular disease risk increases when lipoprotein metabolism is dysfunctional. We have developed a computational model able to derive indicators of lipoprotein production, lipolysis, and uptake processes from a single lipoprotein profile measurement. This is the first study to inves...

  9. Investigation of the cardiovascular effects of apelin 

    E-print Network

    Hamilton-Smith, Katherine Mary; Smith, Katherine Mary Hamilton

    2011-07-05

    Apelin was discovered in 1998 as the endogenous peptide ligand of the orphan APJ receptor. The apelin system is well conserved across vertebrate species and is reported to have cardiovascular effects including positive ...

  10. Peripheral effector mechanism hypothesis of postflight cardiovascular dysfunction.

    PubMed

    Zhang, L F; Yu, Z B; Ma, J; Mao, Q W

    2001-06-01

    Studies on the mechanisms of cardiovascular dysfunction after space-flight are important to illustrate the cardiovascular effect of microgravity and develop appropriate multi-system countermeasures for future long-duration spaceflights. Over the past 10 yr, we have systematically studied the adaptational changes in structure and function of both the heart and vessels, using the tail-suspension rat model to simulate microgravity effects. Our results indicate that simulated microgravity induced atrophic changes and reduced contractility of the heart muscle, and upward- and downward-regulation in structure, function, and innervation state of vessels in the brain and hind body of the rat. In addition, more recent advances in relevant ground-based and space-flight studies from different laboratories have also been reviewed. Based on these studies, it has been speculated that, in addition to hypovolemia, the microgravity-induced adaptational changes in the structure and function of the two main effectors of the cardiovascular system, i.e., the arterial smooth muscle and the cardiac muscle, might be among the most important mechanisms responsible for postflight cardiovascular dysfunction and orthostatic intolerance. In this paper we will review the available evidence with comments. PMID:11396563

  11. Adiponectin and Cardiovascular Disease

    Microsoft Academic Search

    Medhavi Jogi; Mandeep Bajaj

    Adiponectin, an adipocytokine secreted by adipose tissue, enhances insulin sensitivity and inhibits vascular inflammation.\\u000a Hypoadiponectinemia is associated with endothelial dysfunction, hypertension, coronary heart disease, and other cardiovascular\\u000a complications. Furthermore, enhancing adiponectin concentrations by lifestyle changes or pharmacological therapy can have\\u000a cardiovascular-protective effects. In this chapter, we review the association between adiponectin and cardiovascular disease\\u000a and discuss treatment strategies to ameliorate

  12. Imaging in Cardiovascular Research

    Microsoft Academic Search

    Michael Schäfers; Klaus Tiemann; Michael Kuhlmann; Lars Stegger; Klaus Schäfers; Sven Hermann

    \\u000a Despite enormous investment into cardiovascular research on all levels worldwide, cardiovascular events such as myocardial\\u000a infarction, heart failure, tachyarrhythmia or stroke remain the major causes for death and inability in all developed countries.\\u000a Conventional clinical cardiovascular imaging nowadays provides high-resolution visualization of the morphology of vessels\\u000a and the myocardium. To translate the available patient imaging technologies into animals, especially mice

  13. A new current-based control model of the combined cardiovascular and Rotary Left Ventricular Assist Device

    Microsoft Academic Search

    George Faragallah; Yu Wang; Eduardo Divo; Marwan A. Simaan

    2011-01-01

    Rotary Left Ventricular Assist Devices (LVAD) are mechanical pumps implanted in patients with congestive heart failure to assist their heart in pumping the required amount of blood in the circulatory system. Until recently, the combined mathematical model of the LVAD coupled with the left ventricle has assumed the availability of the rotational speed of the pump as the independent control

  14. Tobacco and cardiovascular health.

    PubMed

    Mainali, Prajeena; Pant, Sadip; Rodriguez, Alexis Phillip; Deshmukh, Abhishek; Mehta, Jawahar L

    2015-04-01

    Tobacco consumption has been inextricably intertwined with society and its evolution. At one time, centuries ago, thought to be a sign of refinement and nobility, fortunately, this perception has been changing worldwide. Currently, this change in perception has been so dramatic that laws are enacted to limit tobacco exposure through second-hand smokers. Countless studies continue to emerge on tobacco's healthcare toll to the point that we now consider indisputable facts that smokers have a higher incidence of coronary artery disease, peripheral vascular disease, chronic obstructive pulmonary disease, stroke, among many others. However, there are other less well-known emerging facts that still require close attention such as the effect on the immune and hematopoietic systems. Tobacco smoke is injurious to all major organs in our bodies. With over 30 known carcinogens, it should not be surprising that it affects all aspects of human health. In this chapter, we will focus on the effects of tobacco on cardiovascular health. PMID:25225032

  15. Immersed finite element method and its applications to biological systems

    E-print Network

    Texas at Austin, University of

    ; Cytoskeletal dynamics; Red blood cell; Aggregation; Thrombosis; Cardiovascular system; Micro-circulation; Nano research efforts have been directed to the development of modeling and simulation approaches for fluid

  16. Laser therapy in cardiovascular disease

    NASA Astrophysics Data System (ADS)

    Rindge, David

    2009-02-01

    Cardiovascular disease is the number one cause of death worldwide. It is broadly defined to include anything which adversely affects the heart or blood vessels. One-third of Americans have one or more forms of it. By one estimate, average human life expectancy would increase by seven years if it were eliminated. The mainstream medical model seeks mostly to "manage" cardiovascular disease with pharmaceuticals or to surgically bypass or reopen blocked vessels via angioplasty. These methods have proven highly useful and saved countless lives. Yet drug therapy may be costly and ongoing, and it carries the risk of side effects while often doing little or nothing to improve underlying health concerns. Similarly, angioplasty or surgery are invasive methods which entail risk. Laser therapy1 regenerates tissue, stimulates biological function, reduces inflammation and alleviates pain. Its efficacy and safety have been increasingly well documented in cardiovascular disease of many kinds. In this article we will explore the effects of laser therapy in angina, atherosclerosis, coronary artery disease, hypertension, hyperlipidemia, myocardial infarction, stroke and other conditions. The clinical application of various methods of laser therapy, including laserpuncture and transcutaneous, supravascular and intravenous irradiation of blood will be discussed. Implementing laser therapy in the treatment of cardiovascular disease offers the possibility of increasing the health and wellbeing of patients while reducing the costs and enhancing safety of medical care.

  17. Bile Acids Regulate Cardiovascular Function

    PubMed Central

    Khurana, Sandeep; Raufman, Jean-Pierre; Pallone, Thomas L.

    2011-01-01

    Research over the last decade has uncovered roles for bile acids (BAs) that extend beyond their traditional functions in regulating lipid digestion and cholesterol metabolism. BAs are now recognized as signaling molecules that interact with both plasma membrane and nuclear receptors. Emerging evidence indicates that by interacting with these receptors BAs regulate their own synthesis, glucose and energy homeostasis, and other important physiological events. Herein, we provide a comprehensive review of the actions of BAs on cardiovascular function. In the heart and the systemic circulation, BAs interact with plasma membrane G-protein coupled receptors, e.g. TGR5 and muscarinic receptors, and nuclear receptors, e.g. the farnesoid (FXR) and pregnane (PXR) xenobiotic receptors. BA receptors are expressed in cardiovascular tissue, however, the mechanisms underlying BA-mediated regulation of cardiovascular function remain poorly understood. BAs reduce heart rate by regulating channel conductance and calcium dynamics in sino-atrial and ventricular cardiomyocytes, and regulate vascular tone via both endothelium-dependent and -independent mechanisms. End-stage-liver disease, obstructive jaundice and intrahepatic cholestasis of pregnancy are prominent conditions in which elevated serum BAs alter vascular dynamics. This review focuses on BAs as newly-recognized signaling molecules that modulate cardiovascular function. PMID:21707953

  18. Cardiovascular Toxicities Upon Manganese Exposure

    PubMed Central

    Jiang, Yueming; Zheng, Wei

    2014-01-01

    Manganese (Mn)-induced Parkinsonism has been well documented; however, little attention has been devoted to Mn-induced cardiovascular dysfunction. This review summarizes literature data from both animal and human studies on Mn’s effect on cardiovascular function. Clinical and epidemiological evidence suggests that the incidence of abnormal electrocardiogram (ECG) is significantly higher in Mn-exposed workers than that in the control subjects. The main types of abnormal ECG include sinus tachycardia, sinus bradycardia, sinus arrhythmia, sinister megacardia, and ST-T changes. The accelerated heartbeat and shortened P-R interval appear to be more prominent in female exposed workers than in their male counterparts. Mn-exposed workers display a mean diastolic blood pressure that is significantly lower than that of the control subjects, especially in the young and female exposed workers. Animal studies indicate that Mn is capable of quickly accumulating in heart tissue, resulting in acute or sub-acute cardiovascular disorders, such as acute cardiodepression and hypotension. These toxic outcomes appear to be associated with Mn-induced mitochondrial damage and interaction with the calcium channel in the cardiovascular system. PMID:16382172

  19. Cardiovascular physiology and diseases of amphibians.

    PubMed

    Heinz-Taheny, Kathleen M

    2009-01-01

    The class Amphibia includes three orders of amphibians: the anurans (frogs and toads), urodeles (salamanders, axolotls, and newts), and caecilians. The diversity of lifestyles across these three orders has accompanying differences in the cardiovascular anatomy and physiology allowing for adaptations to aquatic or terrestrial habitats, pulmonic or gill respiration, hibernation, and body elongation (in the caecilian). This article provides a review of amphibian cardiovascular anatomy and physiology with discussion of unique species adaptations. In addition, amphibians as cardiovascular animal models and commonly encountered natural diseases are covered. PMID:19131029

  20. Effect of Piper sarmentosum Extract on the Cardiovascular System of Diabetic Sprague-Dawley Rats: Electron Microscopic Study

    PubMed Central

    Thent, Zar Chi; Seong Lin, Teoh; Das, Srijit; Zakaria, Zaiton

    2012-01-01

    Although Piper sarmentosum (PS) is known to possess the antidiabetic properties, its efficacy towards diabetic cardiovascular tissues is still obscured. The present study aimed to observe the electron microscopic changes on the cardiac tissue and proximal aorta of experimental rats treated with PS extract. Thirty-two male Sprague-Dawley rats were divided into four groups: untreated control group (C), PS-treated control group (CTx), untreated diabetic group (D), and PS-treated diabetic group (DTx). Intramuscular injection of streptozotocin (STZ, 50?mg/kg body weight) was given to induce diabetes. Following 28 days of diabetes induction, PS extract (0.125?g/kg body weight) was administered orally for 28 days. Body weight, fasting blood glucose, and urine glucose levels were measured at 4-week interval. At the end of the study, cardiac tissues and the aorta were viewed under transmission electron microscope (TEM). DTx group showed increase in body weight and decrease in fasting blood glucose and urine glucose level compared to the D group. Under TEM study, DTx group showed lesser ultrastructural degenerative changes in the cardiac tissues and the proximal aorta compared to the D group. The results indicate that PS restores ultrastructural integrity in the diabetic cardiovascular tissues. PMID:23304208

  1. Certain peculiarities of the functioning of the cardiovascular system in bedrest conditions during horizontal and antiorthostatic body positions

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The adequate modeling of physiological reactions inherent to the state of weightlessness has become a matter of particular urgency in space medicine. This modeling is necessary for studying the phenomenology and degree of disorders, prognostication of the crew's health, and developing the various preventive measures employed in space flights. A comparison is made of the physiological effects brought about by bed rest in a horizontal and antiorthostatic body position. A study is done of the influence of brief antiorthostatic hypokinesia, simulating the acute period of adaptation to weightlessness, on circulation and on a number of involved analytical systems. The basic model accepted is antiorthostatic hypokinesia with a body position declination angle of 4 deg (head lower than feet). The experiment's duration is dictated by the objectives of the research.

  2. Cardiovascular Disease in Women

    Microsoft Academic Search

    W. L ANE DUVALL

    2003-01-01

    Almost 62 million Americans have one or more types of cardiovascular disease and, of these, more than 32 million are female. This translates into an average of 1 in 5 women, making cardiovascular disease the leading killer of women in the U.S., responsible for more than half a million deaths a year. While it has been known for some time

  3. Cardiovascular Disease and Diabetes

    MedlinePLUS

    Cardiovascular Disease & Diabetes Updated:Jan 31,2013 The following statistics speak loud and clear that there is a strong correlation between ... content was last reviewed on 7/5/2012. Diabetes • Home • About Diabetes • Why Diabetes Matters Introduction Cardiovascular ...

  4. Simultaneous changes of rhythmic organization in brainstem neurons, respiration, cardiovascular system and EEG between 0.05 Hz and 0.5 Hz.

    PubMed

    Lambertz, M; Langhorst, P

    1998-01-19

    Several neurons from different regions of the brainstem of anesthetized dogs were simultaneously recorded, together with various parameters of the cardiovascular system, respiration, efferent sympathetic neural activities and cortical activity. Often rhythmic changes of activity in the range 0.05-0.5 Hz could be observed in the simultaneously recorded signals. The rhythms were analysed in time domain and by power spectra and their changes depicted over the time. The most striking rhythms between 0.05 Hz and 0.5 Hz are the respiratory rhythm and those rhythms that originate in reticular neurons of the common brainstem system as well as their respective harmonics, i.e. the ranges around the integer multiple frequencies of these basic rhythms. The observed oscillations can vanish and reappear at times. Frequencies of basic oscillations and harmonics and their amplitudes are subject to distinct slow modulations. These modulations can have irregular as well as regular courses. The different rhythms can appear separately or simultaneously in the single signals. The most important phenomenon to be observed is that the rhythms mutually influence their frequencies, which follows the rules of 'relative coordination' as described by E. v. Holst. Such changes of rhythmic activities generally also concern the ranges of harmonics of the basic rhythms. Rhythmic influences on peripheral functional systems, e.g. the cardiovascular system, are most distinct at times when the different rhythms overlap in their frequency ranges. This holds not only for the ranges of basic frequencies, but also for the ranges of their harmonics. Further it was found that rhythms with the same basic frequencies may not only appear simultaneously, but also at various times in the different functional systems. The temporal course of changes of these rhythms, their interactions and their influence on the processing of cardiac rhythmic neuronal discharge patterns is demonstrated. The meaning of the mutually influencing rhythms for the functional organization of central nervous structures is discussed. PMID:9531446

  5. Sodium heat transfer system modeling

    NASA Astrophysics Data System (ADS)

    Baker, A. F.; Fewell, M. E.

    1983-11-01

    The sodium heat transfer system of the international energy agency (IEA) small solar power systems (SSPS) central receiver system (CRS), which includes the heliostat field, receiver, hot and cold storage vessels, and sodium/water steam generator was modeled. The computer code SOLTES (simulator of large thermal energy systems), was used to model this system. The results from SOLTES are compared to measured data.

  6. Cardiovascular health informatics: risk screening and intervention.

    PubMed

    Hartley, Craig J; Naghavi, Morteza; Parodi, Oberdan; Pattichis, Constantinos S; Poon, Carmen C Y; Zhang, Yuan-Ting

    2012-09-01

    Despite enormous efforts to prevent cardiovascular disease (CVD) in the past, it remains the leading cause of death in most countries worldwide. Around two-thirds of these deaths are due to acute events, which frequently occur suddenly and are often fatal before medical care can be given. New strategies for screening and early intervening CVD, in addition to the conventional methods, are therefore needed in order to provide personalized and pervasive healthcare. In this special issue, selected emerging technologies in health informatics for screening and intervening CVDs are reported. These papers include reviews or original contributions on 1) new potential genetic biomarkers for screening CVD outcomes and high-throughput techniques for mining genomic data; 2) new imaging techniques for obtaining faster and higher resolution images of cardiovascular imaging biomarkers such as the cardiac chambers and atherosclerotic plaques in coronary arteries, as well as possible automatic segmentation, identification, or fusion algorithms; 3) new physiological biomarkers and novel wearable and home healthcare technologies for monitoring them in daily lives; 4) new personalized prediction models of plaque formation and progression or CVD outcomes; and 5) quantifiable indices and wearable systems to measure them for early intervention of CVD through lifestyle changes. It is hoped that the proposed technologies and systems covered in this special issue can result in improved CVD management and treatment at the point of need, offering a better quality of life to the patient. PMID:22997187

  7. Cardiovascular Health Informatics: Risk Screening and Intervention

    PubMed Central

    Hartley, Craig J.; Naghavi, Morteza; Parodi, Oberdan; Pattichis, Constantinos S.; Poon, Carmen C. Y.; Zhang, Yuan-Ting

    2014-01-01

    Despite enormous efforts to prevent cardiovascular disease (CVD) in the past, it remains the leading cause of death in most countries worldwide. Around two-thirds of these deaths are due to acute events, which frequently occur suddenly and are often fatal before medical care can be given. New strategies for screening and early intervening CVD, in addition to the conventional methods, are therefore needed in order to provide personalized and pervasive healthcare. In this special issue, selected emerging technologies in health informatics for screening and intervening CVDs are reported. These papers include reviews or original contributions on 1) new potential genetic biomarkers for screening CVD outcomes and high-throughput techniques for mining genomic data; 2) new imaging techniques for obtaining faster and higher resolution images of cardiovascular imaging biomarkers such as the cardiac chambers and atherosclerotic plaques in coronary arteries, as well as possible automatic segmentation, identification, or fusion algorithms; 3) new physiological biomarkers and novel wearable and home healthcare technologies for monitoring them in daily lives; 4) new personalized prediction models of plaque formation and progression or CVD outcomes; and 5) quantifiable indices and wearable systems to measure them for early intervention of CVD through lifestyle changes. It is hoped that the proposed technologies and systems covered in this special issue can result in improved CVD management and treatment at the point of need, offering a better quality of life to the patient. PMID:22997187

  8. Interventional cardiovascular magnetic resonance: still tantalizing

    PubMed Central

    Ratnayaka, Kanishka; Faranesh, Anthony Z; Guttman, Michael A; Kocaturk, Ozgur; Saikus, Christina E; Lederman, Robert J

    2008-01-01

    The often touted advantages of MR guidance remain largely unrealized for cardiovascular interventional procedures in patients. Many procedures have been simulated in animal models. We argue these opportunities for clinical interventional MR will be met in the near future. This paper reviews technical and clinical considerations and offers advice on how to implement a clinical-grade interventional cardiovascular MR (iCMR) laboratory. We caution that this reflects our personal view of the "state of the art." PMID:19114017

  9. The Clinical Performance of an Office-Based Risk Scoring System for Fatal Cardiovascular Diseases in North-East of Iran

    PubMed Central

    Sepanlou, Sadaf G.; Malekzadeh, Reza; Poustchi, Hossein; Sharafkhah, Maryam; Ghodsi, Saeed; Malekzadeh, Fatemeh; Etemadi, Arash; Pourshams, Akram; Pharoah, Paul D.; Abnet, Christian C.; Brennan, Paul; Boffetta, Paolo; Dawsey, Sanford M.; Kamangar, Farin

    2015-01-01

    Background Cardiovascular diseases (CVD) are becoming major causes of death in developing countries. Risk scoring systems for CVD are needed to prioritize allocation of limited resources. Most of these risk score algorithms have been based on a long array of risk factors including blood markers of lipids. However, risk scoring systems that solely use office-based data, not including laboratory markers, may be advantageous. In the current analysis, we validated the office-based Framingham risk scoring system in Iran. Methods The study used data from the Golestan Cohort in North-East of Iran. The following risk factors were used in the development of the risk scoring method: sex, age, body mass index, systolic blood pressure, hypertension treatment, current smoking, and diabetes. Cardiovascular risk functions for prediction of 10-year risk of fatal CVDs were developed. Results A total of 46,674 participants free of CVD at baseline were included. Predictive value of estimated risks was examined. The resulting Area Under the ROC Curve (AUC) was 0.774 (95% CI: 0.762-0.787) in all participants, 0.772 (95% CI: 0.753-0.791) in women, and 0.763 (95% CI: 0.747-0.779) in men. AUC was higher in urban areas (0.790, 95% CI: 0.766-0.815). The predicted and observed risks of fatal CVD were similar in women. However, in men, predicted probabilities were higher than observed. Conclusion The AUC in the current study is comparable to results of previous studies while lipid profile was replaced by body mass index to develop an office-based scoring system. This scoring algorithm is capable of discriminating individuals at high risk versus low risk of fatal CVD. PMID:26011607

  10. Prevalence of stroke/cardiovascular risk factors in Hungary

    NASA Astrophysics Data System (ADS)

    Bodo, M.; Sipos, K.; Thuroczy, G.; Panczel, G.; Ilias, L.; Szonyi, P.; Bodo, M., Jr.; Nebella, T.; Banyasz, A.; Nagy, Z.

    2010-04-01

    A cross-sectional survey was conducted in Hungary using the Cerberus system which includes: 1) a questionnaire addressing the risk factors for stroke/cardiovascular disease; 2) amplifiers to record the pulse waves of cerebral arteries (rheoencephalography) and peripheral arteries, electrocardiogram and electroencephalogram. Additionally, subjects were measured for carotid stenosis by Doppler ultrasound and 12-lead electrocardiogram; subjects were also screened for blood cholesterol, glucose, and triglyceride levels. Prevalence of the following stroke risk factors was identified: overweight, 63.25%; sclerotic brain arteries (by rheoencephalogram), 54.29%; heart disease, 37.92%; pathologic carotid flow, 34.24%; smoking, 30.55%; high blood cholesterol, 28.70%; hypertension, 27.83%; high triglyceride, 24.35%; abnormality in electrocardiogram, 20%; high glucose, 15.95%; symptoms of transient ischemic attack, 16.07%; alcohol abuse, 6.74%; and diabetes, 4.53%. The study demonstrates a possible model for primary cardiovascular disease/stroke prevention. This method offers a standardizable, cost effective, practical technique for mass screenings by identifying the population at high risk for cardiovascular disturbances, especially cerebrovascular disease (primary prevention). In this model, the rheoencephalogram can detect cerebrovascular arteriosclerosis in the susceptibility/presymptomatic phase, earlier than the Doppler ultrasound technique. The method also provides a model for storing analog physiological signals in a computer-based medical record and is a first step in applying an expert system to stroke prevention.

  11. A Computational Model of the Circulating Renin-Angiotensin System and Blood Pressure Regulation

    Microsoft Academic Search

    François Guillaud; Patrick Hannaert

    2010-01-01

    The renin-angiotensin system (RAS) is critical in sodium and blood pressure (BP) regulation, and in cardiovascular-renal (CVR)\\u000a diseases and therapeutics. As a contribution to SAPHIR project, we present a realistic computer model of renin production\\u000a and circulating RAS, integrated into Guyton’s circulatory model (GCM). Juxtaglomerular apparatus, JGA, and Plasma modules were implemented in C ++\\/M2SL (Multi-formalism Multi-resolution Simulation Library) for fusion

  12. MicroRNAs as mediators of cardiovascular disease: Targets to be manipulated.

    PubMed

    Lee, Seahyoung; Choi, Eunhyun; Kim, Sung-Man; Hwang, Ki-Chul

    2015-05-26

    Cardiovascular disease has been the leading cause of death worldwide for the last few decades. Even with the rapid progression of the biomedical field, conquering/managing cardiovascular disease is not an easy task because it is multifactorial disease. One of the key players of the development and progression of numerous diseases is microRNA (miRNA). These small, non-coding RNAs bind to target mRNAs to inhibit translations of and/or degrade the target mRNAs, thus acting as negative regulators of gene expressions. Accumulating evidence indicates that non-physiological expressions of miRNAs contribute to both development and progression of cardiovascular diseases. Since even a single miRNA can have multiple targets, dysregulation of miRNAs can lead to catastrophic changes of proteins that may be important for maintaining physiologic conditions of cells, tissues, and organs. Current knowledge on the role of miRNAs in cardiovascular disease is mostly based on the observational data such as microarray of miRNAs in animal disease models, thus relatively lacking insight of how such dysregulation of miRNAs is initiated and regulated. Consequently, future research should aim to elucidate the more comprehensive mechanisms of miRNA dysregulation during pathogenesis of the cardiovascular system so that appropriate counter-measures to prevent/manage cardiovascular disease can be developed. PMID:26009702

  13. Imaging of cardiovascular dynamics in early mouse embryos with swept source optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Larina, Irina V.; Liebling, Michael; Dickinson, Mary E.; Larin, Kirill V.

    2009-02-01

    Congenital cardiovascular defects are very common, occurring in 1% of live births, and cardiovascular failures are the leading cause of birth defect-related deaths in infants. To improve diagnostics, prevention and treatment of cardiovascular abnormalities, we need to understand not only how cells form the heart and vessels but also how physical factors such as heart contraction and blood flow influence heart development and changes in the circulatory network. Mouse models are an excellent resource for studying cardiovascular development and disease because of the resemblance to humans, rapid generation time, and availability of mutants with cardiovascular defects linked to human diseases. In this work, we present results on development and application of Doppler Swept Source Optical Coherence Tomography (DSS-OCT) for imaging of cardiovascular dynamics and blood flow in the mouse embryonic heart and vessels. Our studies demonstrated that the spatial and temporal resolution of the DSS-OCT makes it possible to perform sensitive measurements of heart and vessel wall movements and to investigate how contractile waves facilitate the movement of blood through the circulatory system.

  14. Modelling of Pathways Systems Biology

    E-print Network

    Timmer, Jens

    Modelling of Pathways Systems Biology Jens Timmer Center for Systems Biology Center for Data;Outline · Systems Biology · JAK-STAT pathway of the Epo receptor · A dynamical model for JAK-STAT pathway · Observing the unobservable · In silico biology: Predicting a new experiment · Infer systems' properties 2

  15. Testosterone and cardiovascular risk.

    PubMed

    Tirabassi, Giacomo; Gioia, Angelo; Giovannini, Lara; Boscaro, Marco; Corona, Giovanni; Carpi, Angelo; Maggi, Mario; Balercia, Giancarlo

    2013-04-01

    Cardiovascular (CV) disease is one of the most common causes of death in the western populations and, nowadays, its incidence is increasing even in the developing countries; although CV disease affects both sexes, it is more frequent in males in whom it shortens the average life expectancy. In this regard, this difference has been wrongly attributed for many years to the negative effects of testosterone (T); however, nowadays, a large amount of evidence suggests that this hormone may have protective effects on the CV system and that, indeed, the low levels of T could be associated with an increased CV risk and with an augmentation of morbidity and mortality in males. Such an aspect gains great relevance in light of the consideration that T decrease, besides occurring as a consequence of rare pathological conditions, can often take place with natural aging, causing a state of "male menopause", also called late-onset hypogonadism. In this review, we aimed to summarize the present state of the art concerning the association between T deficit and CV disease by analyzing the protective role of T on CV system and the relationship of this hormonal lack with metabolic syndrome, CV morbidity and mortality, and with the CV complications, such as ischemic heart disease, heart failure and stroke, that frequently occur in T deficiency. PMID:23475207

  16. Identification of Multichannel Cardiovascular Dynamics Using Dual Laguerre Basis Functions for Noninvasive Cardiovascular Monitoring

    E-print Network

    McCombie, D. B.

    This paper presents a novel method to identify the cardiovascular (CV) system using two distinct peripheral blood pressure (BP) signals. The method can characterize the distinct arterial path dynamics that shape each of ...

  17. Model-free causality analysis of cardiovascular variability detects the amelioration of autonomic control in Parkinson's disease patients undergoing mechanical stimulation.

    PubMed

    Bassani, Tito; Bari, Vlasta; Marchi, Andrea; Tassin, Stefano; Dalla Vecchia, Laura; Canesi, Margherita; Barbic, Franca; Furlan, Raffaello; Porta, Alberto

    2014-07-01

    We tested the hypothesis that causality analysis, applied to the spontaneous beat-to-beat variability of heart period (HP) and systolic arterial pressure (SAP), can identify the improvement of autonomic control linked to plantar mechanical stimulation in patients with Parkinson's disease (PD). A causality index, measuring the strength of the association from SAP to HP variability, and derived according to the Granger paradigm (i.e. SAP causes HP if the inclusion of SAP into the set of signals utilized to describe cardiovascular interactions improves the prediction of HP series), was calculated using both linear model-based (MB) and nonlinear model-free (MF) approaches. Univariate HP and SAP variability indices in time and frequency domains, and bivariate descriptors of the HP-SAP variability interactions were computed as well. We studied ten PD patients (age range: 57-78 years; Hoehn-Yahr scale: 2-3; six males, four females) without orthostatic hypotension or symptoms of orthostatic intolerance and 'on-time' according to their habitual pharmacological treatment. PD patients underwent recordings at rest in a supine position and during a head-up tilt before, and 24 h after, mechanical stimulation was applied to the plantar surface of both feet. The MF causality analysis indicated a greater involvement of baroreflex in regulating HP-SAP variability interactions after mechanical stimulation. Remarkably, MB causality and more traditional univariate or bivariate techniques could not detect changes in cardiovascular regulation after mechanical stimulation, thus stressing the importance of accounting for nonlinear dynamics in PD patients. Due to the higher statistical power of MF causality we suggest its exploitation to monitor the baroreflex control improvement in PD patients, and we encourage the clinical application of the Granger causality approach to evaluate the modification of the autonomic control in relation to the application of a pharmacological treatment, a rehabilitation procedure or external intervention. PMID:24875165

  18. Cardiovascular Interactions CVI Project

    NSDL National Science Digital Library

    PhD Carl F. Rothe (Indiana University School of Medicine Department of Cellular and Integrative Physiology)

    2005-06-22

    The Cardiovascular Interactions Project is an electronic active learning tool that demonstrates the complex and intricate interactions between the functions of the heart and peripheral circulation to provide an adequate cardiac output during various stresses.

  19. Interventional Cardiovascular MRI

    Microsoft Academic Search

    Milind Y. Desai; Albert C. Lardo; Joao A. C. Lima

    Cardiovascular disease continues to be the leading cause of death in the Western world and the incidence is projected to increase\\u000a in the future (1). Traditionally, X-ray techniques have been the mainstay in terms of imaging modality for diagnostic and therapeutic cardiovascular\\u000a procedures. However, there are inherent limitations to this technology including inability to perform three-dimensional imaging,\\u000a poor soft tissue

  20. Avocado Oil Supplementation Modifies Cardiovascular Risk Profile Markers in a Rat Model of Sucrose-Induced Metabolic Changes

    PubMed Central

    Carvajal-Zarrabal, Octavio; Nolasco-Hipolito, Cirilo; Aguilar-Uscanga, M. Guadalupe; Melo-Santiesteban, Guadalupe; Hayward-Jones, Patricia M.; Barradas-Dermitz, Dulce M.

    2014-01-01

    The purpose of this study was to evaluate the effects of avocado oil administration on biochemical markers of cardiovascular risk profile in rats with metabolic changes induced by sucrose ingestion. Twenty-five rats were divided into five groups: a control group (CG; basic diet), a sick group (MC; basic diet plus 30% sucrose solution), and three other groups (MCao, MCac, and MCas; basic diet plus 30% sucrose solution plus olive oil and avocado oil extracted by centrifugation or using solvent, resp.). Glucose, total cholesterol, triglycerides, phospholipids, low- and high-density lipoproteins (LDL, HDL), very low-density lipoprotein (VLDL), lactic dehydrogenase, creatine kinase, and high sensitivity C-reactive protein concentration were analyzed. Avocado oil reduces TG, VLDL, and LDL levels, in the LDL case significantly so, without affecting HDL levels. An effect was exhibited by avocado oil similar to olive oil, with no significant difference between avocado oil extracted either by centrifugation or solvent in myocardial injury biochemical indicators. Avocado oil decreased hs-CRP levels, indicating that inflammatory processes were partially reversed. These findings suggested that avocado oil supplementation has a positive health outcome because it reduces inflammatory events and produces positive changes in the biochemical indicators studied, related to the development of metabolic syndrome. PMID:24719499

  1. Cardiovascular supply cost negotiations: partnering for the future.

    PubMed

    Keast, Robert K; Maxwell, Stephen G; Barkman, Sandy; Chetcuti, Stanley; Oral, Hakan; Eagle, Kim A

    2010-01-01

    As a major expense driver to cardiovascular programs, supply costs related to electrophysiology and cardiac catheterization procedures directly link to the overall financial health of organizations associated with those programs. Because of this, it is important that institutions establish a logical and resolute approach to obtaining supply pricing that maximizes cost-saving opportunities, buffers their organizations from escalating costs related to the advances in available technologies, defines supply chain expectations while preserving clinicians' access to high-quality cardiovascular supplies, and maintains the availability of the full spectrum of products to our physicians, referring physicians, and patients. In a joint effort with physicians, administration, and suppliers, and in the spirit of partnership, the University of Michigan Health System has developed and implemented such a model that illustrates the opportunities to be gained. PMID:20145470

  2. [Homocysteine and cardiovascular risk].

    PubMed

    Lutteri, L; Chapelle, J P; Gielen, J

    1999-06-01

    Homocystinuria is an uncommon genetic disease characterized by a marked increase of serum homocysteine (HCY), an intermediate of methionine metabolism. In patients with homocystinuria, hyperhomocysteinemia promotes the development of atherosclerotic lesions and is responsible for premature coronary artery disease. Recently, several studies have also demonstrated that moderate hyperhomocysteinemia--not necessarily linked to an inborn metabolic defect--may also be considered as an independant risk factor for cardiovascular disease. The main mechanisms of HCY atherogenic action are thought to be LDL oxydation, inhibition of vascular endothelium growth combined with stimulation of smooth muscular cells proliferation, and interference with the coagulation and fibrinolytic systems. Cofactors of key enzymes in HCY metabolism, folic acid, vitamin B12 and vitamin B6, may be given, alone or in combination, for the treatment of hyperhomocysteinemia. Homocysteinemia can be assessed by basal plasma HCY concentration and/or by HCY levels measured after a methionine loading test. Mainly measured till now in specialized laboratories using rather complex techniques (HPLC, GCMS, amino acid analyser ...), HCY determination is today spreading widely owing to the development of automated immunoassays. PMID:10446525

  3. Cardiovascular Dementia - A Different Perspective

    PubMed Central

    Kumari, Udhaya; Heese, Klaus

    2010-01-01

    The number of dementia patients has been growing in recent years and dementia represents a significant threat to aging people all over the world. Recent research has shown that the number of people affected by Alzheimer’s disease (AD) and dementia is growing at an epidemic pace. The rapidly increasing financial and personal costs will affect the world's economies, health care systems, and many families. Researchers are now exploring a possible connection among AD, vascular dementia (VD), diabetes mellitus (type 2, T2DM) and cardiovascular diseases (CD). This correlation may be due to a strong association of cardiovascular risk factors with AD and VD, suggesting that these diseases share some biologic pathways. Since heart failure is associated with an increased risk of AD and VD, keeping the heart healthy may prove to keep the brain healthy as well. The risk for dementia is especially high when diabetes mellitus is comorbid with severe systolic hypertension or heart disease. In addition, the degree of coronary artery disease (CAD) is independently associated with cardinal neuropathological lesions of AD. Thus, the contribution of T2DM and CD to AD and VD implies that cardiovascular therapies may prove useful in preventing AD and dementia. PMID:20448820

  4. Cardiovascular dementia - a different perspective.

    PubMed

    Kumari, Udhaya; Heese, Klaus

    2010-01-01

    The number of dementia patients has been growing in recent years and dementia represents a significant threat to aging people all over the world. Recent research has shown that the number of people affected by Alzheimer's disease (AD) and dementia is growing at an epidemic pace. The rapidly increasing financial and personal costs will affect the world's economies, health care systems, and many families. Researchers are now exploring a possible connection among AD, vascular dementia (VD), diabetes mellitus (type 2, T2DM) and cardiovascular diseases (CD). This correlation may be due to a strong association of cardiovascular risk factors with AD and VD, suggesting that these diseases share some biologic pathways. Since heart failure is associated with an increased risk of AD and VD, keeping the heart healthy may prove to keep the brain healthy as well. The risk for dementia is especially high when diabetes mellitus is comorbid with severe systolic hypertension or heart disease. In addition, the degree of coronary artery disease (CAD) is independently associated with cardinal neuropathological lesions of AD. Thus, the contribution of T2DM and CD to AD and VD implies that cardiovascular therapies may prove useful in preventing AD and dementia. PMID:20448820

  5. Optimization of nanoparticles for cardiovascular tissue engineering

    NASA Astrophysics Data System (ADS)

    Izadifar, Mohammad; Kelly, Michael E.; Haddadi, Azita; Chen, Xiongbiao

    2015-06-01

    Nano-particulate delivery systems have increasingly been playing important roles in cardiovascular tissue engineering. Properties of nanoparticles (e.g. size, polydispersity, loading capacity, zeta potential, morphology) are essential to system functions. Notably, these characteristics are regulated by fabrication variables, but in a complicated manner. This raises a great need to optimize fabrication process variables to ensure the desired nanoparticle characteristics. This paper presents a comprehensive experimental study on this matter, along with a novel method, the so-called Geno-Neural approach, to analyze, predict and optimize fabrication variables for desired nanoparticle characteristics. Specifically, ovalbumin was used as a protein model of growth factors used in cardiovascular tissue regeneration, and six fabrication variables were examined with regard to their influence on the characteristics of nanoparticles made from high molecular weight poly(lactide-co-glycolide). The six-factor five-level central composite rotatable design was applied to the conduction of experiments, and based on the experimental results, a geno-neural model was developed to determine the optimum fabrication conditions. For desired particle sizes of 150, 200, 250 and 300 nm, respectively, the optimum conditions to achieve the low polydispersity index, higher negative zeta potential and higher loading capacity were identified based on the developed geno-neural model and then evaluated experimentally. The experimental results revealed that the polymer and the external aqueous phase concentrations and their interactions with other fabrication variables were the most significant variables to affect the size, polydispersity index, zeta potential, loading capacity and initial burst release of the nanoparticles, while the electron microscopy images of the nanoparticles showed their spherical geometries with no sign of large pores or cracks on their surfaces. The release study revealed that the onset of the third phase of release can be affected by the polymer concentration. Circular dichroism spectroscopy indicated that ovalbumin structural integrity is preserved during the encapsulation process. Findings from this study would greatly contribute to the design of high molecular weight poly(lactide-co-glycolide) nanoparticles for prolonged release patterns in cardiovascular engineering.

  6. Sex Differences in the Developmental Origins of Cardiovascular Disease

    PubMed Central

    Intapad, Suttira; Ojeda, Norma B.; Dasinger, John Henry

    2014-01-01

    The Developmental Origins of Health and Disease (DOHaD) proposes that adverse events during early life program an increased risk for cardiovascular disease. Experimental models provide proof of concept but also indicate that insults during early life program sex differences in adult blood pressure and cardiovascular risk. This review will highlight the potential mechanisms that contribute to the etiology of sex differences in the developmental programming of cardiovascular disease. PMID:24583768

  7. System of systems modeling and simulation.

    SciTech Connect

    Lawton, Craig R.; Campbell, James E.; Anderson, Dennis James; Thompson, Bruce Miles; Longsine, Dennis E. (Intera, Inc., Austin, TX.); Shirah, Donald N.; Cranwell, Robert M.

    2005-02-01

    Analyzing the performance of a complex System of Systems (SoS) requires a systems engineering approach. Many such SoS exist in the Military domain. Examples include the Army's next generation Future Combat Systems 'Unit of Action' or the Navy's Aircraft Carrier Battle Group. In the case of a Unit of Action, a system of combat vehicles, support vehicles and equipment are organized in an efficient configuration that minimizes logistics footprint while still maintaining the required performance characteristics (e.g., operational availability). In this context, systems engineering means developing a global model of the entire SoS and all component systems and interrelationships. This global model supports analyses that result in an understanding of the interdependencies and emergent behaviors of the SoS. Sandia National Laboratories will present a robust toolset that includes methodologies for developing a SoS model, defining state models and simulating a system of state models over time. This toolset is currently used to perform logistics supportability and performance assessments of the set of Future Combat Systems (FCS) for the U.S. Army's Program Manager Unit of Action.

  8. Serum FGF23 and Risk of Cardiovascular Events in Relation to Mineral Metabolism and Cardiovascular Pathology

    PubMed Central

    Ärnlöv, Johan; Carlsson, Axel C.; Sundström, Johan; Ingelsson, Erik; Larsson, Anders; Lind, Lars

    2013-01-01

    Summary Background and objectives Circulating fibroblast growth factor-23 is associated with adverse cardiovascular outcomes in CKD and non-CKD individuals, but the underlying mechanism remains unclear. This study tested whether this association is independent of mineral metabolism and indices of subclinical cardiovascular pathology. Design, setting, participants, & measurements The prospective association between fibroblast growth factor-23 and major cardiovascular events (a composite of hospital-treated myocardial infarction, hospital-treated stroke, or all-cause mortality) was investigated in the community-based Prospective Investigation of the Vasculature in Uppsala Seniors (n=973; mean age=70 years, 50% women) using multivariate logistic regression. Subjects were recruited between January of 2001 and June of 2004. Results During follow-up (median=5.1 years), 112 participants suffered a major cardiovascular event. In logistic regression models adjusted for age, sex, and estimated GFR, higher fibroblast growth factor-23 was associated with increased risk for major cardiovascular events (odds ratio for tertiles 2 and 3 versus tertile 1=1.92, 95% confidence interval=1.19–3.09, P<0.01). After additional adjustments in the model, adding established cardiovascular risk factors, confounders of mineral metabolism (calcium, phosphate, parathyroid hormone, and 25(OH)-vitamin D), and indices of subclinical pathology (flow-mediated vasodilation, endothelial-dependent and -independent vasodilation, arterial stiffness, and atherosclerosis and left ventricular mass) attenuated this relationship, but it remained significant (odds ratio for tertiles 2 and 3 versus tertile 1=1.69, 95% confidence interval=1.01–2.82, P<0.05). Conclusions Fibroblast growth factor-23 is an independent predictor of cardiovascular events in the community, even after accounting for mineral metabolism abnormalities and subclinical cardiovascular damage. Circulating fibroblast growth factor-23 may reflect novel and important aspects of cardiovascular risk yet to be unraveled. PMID:23335040

  9. EXPOSURE ANALYSIS MODELING SYSTEM (EXAMS)

    EPA Science Inventory

    The Exposure Analysis Modeling System (EXAMS), first published in 1982 (EPA-600/3-82-023), provides interactive computer software for formulating aquatic ecosystem models and rapidly evaluating the fate, transport, and exposure concentrations of synthetic organic chemicals--pesti...

  10. Public Health Options for Improving Cardiovascular Health Among Older Americans

    PubMed Central

    Keenan, Nora L.; Clayton, Paula F.; Pandey, Dilip K.; Hong, Yuling

    2012-01-01

    Life expectancy at birth has increased from 74 years in 1980 to 78 years in 2006. Older adults (aged 65 years and older) are living longer with cardiovascular conditions, which are leading causes of death and disability and thus an important public health concern. We describe several major issues, including the impact of comorbidities, the role of cognitive health, prevention and intervention approaches, and opportunities for collaboration to strengthen the public health system. Prevention can be effective at any age, including for older adults. Public health models focusing on policy, systems, and environmental change approaches have the goal of providing social and physical environments and promoting healthy choices. PMID:22698028

  11. Modelling STATCOM into power systems

    Microsoft Academic Search

    H. F. Wang

    1999-01-01

    This paper establishes the linearized Phillips-Heffron model of a power system installed with a STATCOM (static synchronous compensator) and demonstrates the applications of the model in analysing the damping effect of the STATCOM and designing a STATCOM stabilizer to improve power system oscillation stability. Both cases of single-machine infinite-bus and multi-machine power systems are studied and an example power system

  12. Metabolic syndrome in Spanish patients with psoriasis needing systemic therapy: Prevalence and association with cardiovascular disease in PSO-RISK, a cross-sectional study.

    PubMed

    Belinchón, I; Vanaclocha, F; de la Cueva-Dobao, P; Coto-Segura, P; Labandeira, J; Herranz, P; Taberner, R; Juliá, B; Cea-Calvo, L; Puig, L

    2014-11-28

    Abstract Background: Increasing evidence indicates a relationship between psoriasis and metabolic syndrome (MS). We evaluated the prevalence of MS in patients receiving systemic treatment for psoriasis in Spain, and its relationship to cardiovascular disease (CVD). Methods: This cross-sectional, multicenter, non-interventional study enrolled 368 patients with moderate-to-severe psoriasis requiring systemic treatment. Clinical parameters for psoriasis, CV risk factors, MS and CVD were assessed. Descriptive and logistic regression analyses were performed. Results: 352 patients were included (median psoriasis duration: 18 years, plaque psoriasis [95.7%], psoriatic arthritis [22.8%]). Overall, 132 patients (37.5%) fulfilled diagnostic criteria for MS; the most prevalent MS components were high blood pressure and increased waist circumference. Patients with MS were older, more likely to be obese and to have a sedentary lifestyle and hypercholesterolemia than those without MS. CVD was more prevalent in patients with MS than in those without (29.5% versus 15.9%, p?=?0.002), particularly coronary heart disease (CHD), myocardial infarction and heart failure. MS was independently associated with CVD (OR 1.98, p?=?0.018) and CHD (OR 2.02, p?=?0.044). Conclusion: The prevalence of MS was high among patients with moderate-to-severe psoriasis requiring systemic treatment, and was associated with a higher prevalence of CVD. Dermatologists should consider implementing simple screening protocols. PMID:25362972

  13. Statistical validation of system models

    SciTech Connect

    Barney, P. [Sandia National Labs., Albuquerque, NM (United States); Ferregut, C.; Perez, L.E. [Texas Univ., El Paso, TX (United States); Hunter, N.F. [Los Alamos National Lab., NM (United States); Paez, T.L. [Sandia National Labs., Albuquerque, NM (United States)

    1997-01-01

    It is common practice in system analysis to develop mathematical models for system behavior. Frequently, the actual system being modeled is also available for testing and observation, and sometimes the test data are used to help identify the parameters of the mathematical model. However, no general-purpose technique exists for formally, statistically judging the quality of a model. This paper suggests a formal statistical procedure for the validation of mathematical models of systems when data taken during operation of the system are available. The statistical validation procedure is based on the bootstrap, and it seeks to build a framework where a statistical test of hypothesis can be run to determine whether or not a mathematical model is an acceptable model of a system with regard to user-specified measures of system behavior. The approach to model validation developed in this study uses experimental data to estimate the marginal and joint confidence intervals of statistics of interest of the system. These same measures of behavior are estimated for the mathematical model. The statistics of interest from the mathematical model are located relative to the confidence intervals for the statistics obtained from the experimental data. These relative locations are used to judge the accuracy of the mathematical model. An extension of the technique is also suggested, wherein randomness may be included in the mathematical model through the introduction of random variable and random process terms. These terms cause random system behavior that can be compared to the randomness in the bootstrap evaluation of experimental system behavior. In this framework, the stochastic mathematical model can be evaluated. A numerical example is presented to demonstrate the application of the technique.

  14. Cardiovascular regulation during sleep quantified by symbolic coupling traces

    NASA Astrophysics Data System (ADS)

    Suhrbier, A.; Riedl, M.; Malberg, H.; Penzel, T.; Bretthauer, G.; Kurths, J.; Wessel, N.

    2010-12-01

    Sleep is a complex regulated process with short periods of wakefulness and different sleep stages. These sleep stages modulate autonomous functions such as blood pressure and heart rate. The method of symbolic coupling traces (SCT) is used to analyze and quantify time-delayed coupling of these measurements during different sleep stages. The symbolic coupling traces, defined as the symmetric and diametric traces of the bivariate word distribution matrix, allow the quantification of time-delayed coupling. In this paper, the method is applied to heart rate and systolic blood pressure time series during different sleep stages for healthy controls as well as for normotensive and hypertensive patients with sleep apneas. Using the SCT, significant different cardiovascular mechanisms not only between the deep sleep and the other sleep stages but also between healthy subjects and patients can be revealed. The SCT method is applied to model systems, compared with established methods, such as cross correlation, mutual information, and cross recurrence analysis and demonstrates its advantages especially for nonstationary physiological data. As a result, SCT proves to be more specific in detecting delays of directional interactions than standard coupling analysis methods and yields additional information which cannot be measured by standard parameters of heart rate and blood pressure variability. The proposed method may help to indicate the pathological changes in cardiovascular regulation and also the effects of continuous positive airway pressure therapy on the cardiovascular system.

  15. Cardiovascular disease mortality.

    PubMed Central

    Onwuanyi, Anekwe E.; Clarke, Aubrey; Vanderbush, Eric

    2003-01-01

    Although mortality from cardiovascular diseases (CVDs) has been declining, it remains the leading cause of death among urban U.S. blacks. McCord and Freeman reported CVD as the major contributor to excess mortality in Central Harlem. However the disease-specific CVD mortality was not assessed. Thus, it was unclear what the distribution of specific CVDs was in Central Harlem and their contribution to excess mortality. We reviewed the vital statistics records of New York City (NYC) Department of Health for 1990 and identified all cases in which the cause of death was coded as cardiovascular (International Classification of Diseases-ICD, 9th Revision, codes 391, 393-398, 401-404, 410, 411, 414-417, 420-438 and 440-444). The total and disease-specific CVD mortality for NYC and Central Harlem were calculated using the appropriate 1990 census data as the denominator. Central Harlem residents aged between 25-64 years were at least twice as likely to die from cardiovascular causes, compared to NYC residents. Hypertension-related deaths, ICD codes 401 (essential hypertension), 402 (hypertensive heart disease), 403 (hypertensive renal disease), and 404 (hypertensive heart and renal disease), were the major cause of excess death for men and women in Central Harlem. These findings show the importance of hypertension as the main determinant of the excess cardiovascular mortality in urban blacks and suggest an increased risk of cardiovascular death in blacks residing in Central Harlem. PMID:14717470

  16. Nutrition and cardiovascular health.

    PubMed

    Berciano, Silvia; Ordovás, José M

    2014-09-01

    A multitude of studies have been published on the relationship between cardiovascular disease risk and a variety of nutrients, foods, and dietary patterns. Despite the well-accepted notion that diet has a significant influence on the development and prevention of cardiovascular disease, the foods considered healthy and harmful have varied over the years. This review aims to summarize the current scientific evidence on the cardioprotective effect of those foods and nutrients that have been considered healthy as well as those that have been deemed unhealthy at any given time in history. For this purpose, we reviewed the most recent literature using as keywords foods and nutrients (ie, meat, omega-3) and cardiovascular disease-related terms (ie, cardiovascular diseases, stroke). Emphasis has been placed on meta-analyses and Cochrane reviews. In general, there is a paucity of intervention studies with a high level of evidence supporting the benefits of healthy foods (ie, fruits and vegetables), whereas the evidence supporting the case against those foods considered less healthy (ie, saturated fat) seems to be weakened by most recent evidence. In summary, most of the evidence supporting the benefits and harms of specific foods and nutrients is based on observational epidemiological studies. The outcome of randomized clinical trials reveals a more confusing picture with most studies providing very small effects in one direction or another; the strongest evidence comes from dietary patterns. The current status of the relationship between diet and cardiovascular disease risk calls for more tailored recommendations based on genomic technologies. PMID:25172070

  17. Anthocyanins in Cardiovascular Disease1

    PubMed Central

    Wallace, Taylor C.

    2011-01-01

    Anthocyanins are a group of abundant and widely consumed flavonoid constituents that occur ubiquitously in the plant kingdom, providing the bright red-orange to blue-violet colors present in many fruit- and vegetable-based food products. Their intake has been estimated to be up to 9-fold higher than that of other dietary flavonoids. Anthocyanins have become increasingly important to the food industry as their use as natural alternatives to artificial colors has become widespread and knowledge of their health-promoting properties has become more evident. Epidemiological studies suggest that increased consumption of anthocyanins lowers the risk of cardiovascular disease (CVD), the most common cause of mortality among men and women. Anthocyanins frequently interact with other phytochemicals, exhibiting synergistic biological effects but making contributions from individual components difficult to decipher. Over the past 2 decades, many peer-reviewed publications have demonstrated that in addition to their noted in vitro antioxidant activity, anthocyanins may regulate different signaling pathways involved in the development of CVD. This review summarizes the latest developments on the bioavailability/bioactivity and CVD preventative activities of anthocyanins, including results from in vitro cell culture and in vivo animal model systems as related to their multiple proposed mechanisms of action. Limited yet promising data from epidemiological studies and human clinical trials are also presented. Future studies aimed at enhancing the absorption of anthocyanins and characterizing their metabolic and/or breakdown products are necessary to ultimately evaluate their use for protection/prevention against the development of CVD. PMID:22211184

  18. Structural dynamics system model reduction

    NASA Technical Reports Server (NTRS)

    Chen, J. C.; Rose, T. L.; Wada, B. K.

    1987-01-01

    Loads analysis for structural dynamic systems is usually performed by finite element models. Because of the complexity of the structural system, the model contains large number of degree-of-freedom. The large model is necessary since details of the stress, loads and responses due to mission environments are computed. However, a simplified model is needed for other tasks such as pre-test analysis for modal testing, and control-structural interaction studies. A systematic method of model reduction for modal test analysis is presented. Perhaps it will be of some help in developing a simplified model for the control studies.

  19. Modeling formalisms in Systems Biology

    PubMed Central

    2011-01-01

    Systems Biology has taken advantage of computational tools and high-throughput experimental data to model several biological processes. These include signaling, gene regulatory, and metabolic networks. However, most of these models are specific to each kind of network. Their interconnection demands a whole-cell modeling framework for a complete understanding of cellular systems. We describe the features required by an integrated framework for modeling, analyzing and simulating biological processes, and review several modeling formalisms that have been used in Systems Biology including Boolean networks, Bayesian networks, Petri nets, process algebras, constraint-based models, differential equations, rule-based models, interacting state machines, cellular automata, and agent-based models. We compare the features provided by different formalisms, and discuss recent approaches in the integration of these formalisms, as well as possible directions for the future. PMID:22141422

  20. A Model for Systemic Control

    NASA Astrophysics Data System (ADS)

    Schwaninger, Markus; Ambroz, Kristjan; Olaya, Camilo

    2006-06-01

    Where should one begin with a design for the self-control of social systems? That is the question addressed by this paper. The traditional concepts of control rest on the feedback loop; control is essential to the attainment of goals. However, the simple feedback loop is insufficient for the modeling of a control system for an organization or other social system. For those systems, which search for multiple goals, it is necessary to design multilevel control systems incorporating the notion of pre-control. This eminently anticipatory function has hardly been considered by past research. Pre-control as understood here is a higher-order control that takes place between different logical levels of a control system. The Model of Systemic Control (MSC), a framework for multilevel control with pre-control relationships, is expounded and illustrated by means of a System Dynamics model.

  1. Modelling Message Handling System

    Microsoft Academic Search

    Insu Song; Pushkar Piggott

    2003-01-01

    \\u000a This paper introduces a new approach to designing a Message Handling Assistant (MA). It provides a generic model of an MA\\u000a and an intention extraction function for text messages using speech act theory and the belief-desire-intention (BDI) model\\u000a of rational agency. The model characterizes the desired behaviors of an MA and the relationships between the MA, its user,\\u000a and other

  2. SP-100 control system modeling

    NASA Technical Reports Server (NTRS)

    Meyer, R. A.; Halfen, F. J.; Alley, A. D.

    1987-01-01

    SP-100 Control Systems modeling was done using a thermal hydraulic transient analysis model called ARIES-S. The ARIES-S Computer Simulation provides a basis for design, integration and analysis of the reactor including the control and protection systems. It is a modular digital computer simulation written in FORTRAN that operates interactively in real time on a VAX minicomputer.

  3. Space: Modeling the Solar System

    NSDL National Science Digital Library

    2010-01-01

    In this activity, students compare and contrast the diameters of the other planets in the solar system to that of the Earth, create a scale factor based on a reasonable size for the Earth's model and build a scale model of the solar system.

  4. Open Systems Interconnection (OSI) Model

    NSDL National Science Digital Library

    Castro, Tony

    Created by Tony Castro of the Information and Communications Technologies Center (ICT), this simulation demonstrates network architecture and all its layers based on the Open Systems Interconnection (OSI) model. This resource is a helpful addition to any course on information and communications technologies as it allows students to see exactly how the model works in information systems.

  5. The Community Climate System Model

    Microsoft Academic Search

    Maurice Blackmon; Byron Boville; Frank Bryan; Robert Dickinson; Peter Gent; Jeffrey Kiehl; Richard Moritz; David Randall; Jagadish Shukla; Susan Solomon; Gordon Bonan; Scott Doney; Inez Fung; James Hack; Elizabeth Hunke; James Hurrell; John Kutzbach; Jerry Meehl; Bette Otto-Bliesner; R. Saravanan; Edwin K. Schneider; Lisa Sloan; Michael Spall; Karl Taylor; Joseph Tribbia; Warren Washington

    2001-01-01

    The Community Climate System Model (CCSM) has been created to represent the principal components of the climate system and their interactions. Development and applications of the model are carried out by the U.S. climate research community, thus taking advantage of both wide intellectual participation and computing capabilities beyond those available to most individual U.S. institutions. This article outlines the history

  6. Cardiovascular and pulmonary adverse events in patients treated with BCR-ABL inhibitors: Data from the FDA Adverse Event Reporting System.

    PubMed

    Cortes, Jorge; Mauro, Michael; Steegmann, Juan Luis; Saglio, Giuseppe; Malhotra, Rachpal; Ukropec, Jon A; Wallis, Nicola T

    2015-04-01

    Rare but serious cardiovascular and pulmonary adverse events (AEs) have been reported in patients with chronic myeloid leukemia treated with BCR-ABL inhibitors. Clinical trial data may not reflect the full AE profile of BCR-ABL inhibitors because of stringent study entry criteria, relatively small sample size, and limited duration of follow-up. To determine the utility of the FDA AE Reporting System (FAERS) surveillance database for identifying AEs possibly associated with the BCR-ABL inhibitors imatinib, dasatinib, and nilotinib in the postmarketing patient population, we conducted Multi-Item Gamma Poisson Shrinker disproportionality analyses of FAERS reports on AEs in relevant system organ classes. Signals consistent with the known safety profiles of these agents as well as signals for less well-described AEs were detected. Bone marrow necrosis, conjunctival hemorrhage, and peritoneal fluid retention events were uniquely associated with imatinib. AEs that most commonly reached the threshold for dasatinib consisted of terms relating to hemorrhage and fluid retention, including pleural effusion and pericardial effusion. Most terms that reached the threshold solely with nilotinib were related to peripheral and cardiac vascular events. Although this type of analysis cannot determine AE incidence or establish causality, these findings elucidate the AEs reported in patients treated with BCR-ABL inhibitors across multiple clinical trials and in the community setting for all approved and nonapproved indications, suggesting drug-AE associations warrant further investigation. These findings emphasize the need to consider patient comorbidities when selecting amongst BCR-ABL inhibitors. PMID:25580915

  7. Lipoprotein Metabolism Indicators Improve Cardiovascular Risk Prediction

    PubMed Central

    van Schalkwijk, Daniël B.; de Graaf, Albert A.; Tsivtsivadze, Evgeni; Parnell, Laurence D.; van der Werff-van der Vat, Bianca J. C.; van Ommen, Ben; van der Greef, Jan; Ordovás, José M.

    2014-01-01

    Background Cardiovascular disease risk increases when lipoprotein metabolism is dysfunctional. We have developed a computational model able to derive indicators of lipoprotein production, lipolysis, and uptake processes from a single lipoprotein profile measurement. This is the first study to investigate whether lipoprotein metabolism indicators can improve cardiovascular risk prediction and therapy management. Methods and Results We calculated lipoprotein metabolism indicators for 1981 subjects (145 cases, 1836 controls) from the Framingham Heart Study offspring cohort in which NMR lipoprotein profiles were measured. We applied a statistical learning algorithm using a support vector machine to select conventional risk factors and lipoprotein metabolism indicators that contributed to predicting risk for general cardiovascular disease. Risk prediction was quantified by the change in the Area-Under-the-ROC-Curve (?AUC) and by risk reclassification (Net Reclassification Improvement (NRI) and Integrated Discrimination Improvement (IDI)). Two VLDL lipoprotein metabolism indicators (VLDLE and VLDLH) improved cardiovascular risk prediction. We added these indicators to a multivariate model with the best performing conventional risk markers. Our method significantly improved both CVD prediction and risk reclassification. Conclusions Two calculated VLDL metabolism indicators significantly improved cardiovascular risk prediction. These indicators may help to reduce prescription of unnecessary cholesterol-lowering medication, reducing costs and possible side-effects. For clinical application, further validation is required. PMID:24667559

  8. Propulsive Reaction Control System Model

    NASA Technical Reports Server (NTRS)

    Brugarolas, Paul; Phan, Linh H.; Serricchio, Frederick; San Martin, Alejandro M.

    2011-01-01

    This software models a propulsive reaction control system (RCS) for guidance, navigation, and control simulation purposes. The model includes the drive electronics, the electromechanical valve dynamics, the combustion dynamics, and thrust. This innovation follows the Mars Science Laboratory entry reaction control system design, and has been created to meet the Mars Science Laboratory (MSL) entry, descent, and landing simulation needs. It has been built to be plug-and-play on multiple MSL testbeds [analysis, Monte Carlo, flight software development, hardware-in-the-loop, and ATLO (assembly, test and launch operations) testbeds]. This RCS model is a C language program. It contains two main functions: the RCS electronics model function that models the RCS FPGA (field-programmable-gate-array) processing and commanding of the RCS valve, and the RCS dynamic model function that models the valve and combustion dynamics. In addition, this software provides support functions to initialize the model states, set parameters, access model telemetry, and access calculated thruster forces.

  9. Mitochondrial Dynamics in Cardiovascular Health and Disease

    PubMed Central

    Ong, Sang-Bing; Hall, Andrew R.

    2013-01-01

    Abstract Significance: Mitochondria are dynamic organelles capable of changing their shape and distribution by undergoing either fission or fusion. Changes in mitochondrial dynamics, which is under the control of specific mitochondrial fission and fusion proteins, have been implicated in cell division, embryonic development, apoptosis, autophagy, and metabolism. Although the machinery for modulating mitochondrial dynamics is present in the cardiovascular system, its function there has only recently been investigated. In this article, we review the emerging role of mitochondrial dynamics in cardiovascular health and disease. Recent Advances: Changes in mitochondrial dynamics have been implicated in vascular smooth cell proliferation, cardiac development and differentiation, cardiomyocyte hypertrophy, myocardial ischemia-reperfusion injury, cardioprotection, and heart failure. Critical Issues: Many of the experimental studies investigating mitochondrial dynamics in the cardiovascular system have been confined to cardiac cell lines, vascular cells, or neonatal cardiomyocytes, in which mitochondria are distributed throughout the cytoplasm and are free to move. However, in the adult heart where mitochondrial movements are restricted by their tightly-packed distribution along myofibrils or beneath the subsarcolemma, the relevance of mitochondrial dynamics is less obvious. The investigation of transgenic mice deficient in cardiac mitochondrial fission or fusion proteins should help elucidate the role of mitochondrial dynamics in the adult heart. Future Directions: Investigating the role of mitochondrial dynamics in cardiovascular health and disease should result in the identification of novel therapeutic targets for treating patients with cardiovascular disease, the leading cause of death and disability globally. Antioxid. Redox Signal. 19, 400—414. PMID:22793879

  10. Development of a hydraulic model of the human systemic circulation

    NASA Technical Reports Server (NTRS)

    Sharp, M. K.; Dharmalingham, R. K.

    1999-01-01

    Physical and numeric models of the human circulation are constructed for a number of objectives, including studies and training in physiologic control, interpretation of clinical observations, and testing of prosthetic cardiovascular devices. For many of these purposes it is important to quantitatively validate the dynamic response of the models in terms of the input impedance (Z = oscillatory pressure/oscillatory flow). To address this need, the authors developed an improved physical model. Using a computer study, the authors first identified the configuration of lumped parameter elements in a model of the systemic circulation; the result was a good match with human aortic input impedance with a minimum number of elements. Design, construction, and testing of a hydraulic model analogous to the computer model followed. Numeric results showed that a three element model with two resistors and one compliance produced reasonable matching without undue complication. The subsequent analogous hydraulic model included adjustable resistors incorporating a sliding plate to vary the flow area through a porous material and an adjustable compliance consisting of a variable-volume air chamber. The response of the hydraulic model compared favorably with other circulation models.

  11. Modeling of component based systems

    Microsoft Academic Search

    Weizhong Shao; Gang Huang; Haiyan Zhao

    2006-01-01

    Component based software development (CBSD) becomes a popular paradigm for Internet based systems. Compared to other popular paradigms, CBSD supports the development from reusable components other than the development from the scratch. Consequently, modeling becomes more important than programming and the modeling techniques in traditional paradigms have to be changed more or less. Particularly, improper selection and misuse of modeling

  12. Sodium heat transfer system modeling

    SciTech Connect

    Baker, A.F.; Fewell, M.E.

    1983-01-01

    The sodium heat transfer system of the International Energy Agency (IEA) Small Solar Power Systems (SSPS) Central Receiver System (CRS), which includes the heliostat field, receiver, hot and cold storage vessels, and sodium/water steam generator has been modeled. The computer code SOLTES (Simulator of Large Thermal Energy Systems), developed by Sandia National Laboratories, was used to model this system. Based on data provided to Sandia by the IEA-SSPS/CRS project, the results from SOLTES are compared to measured data. The comparison between measured data and predictions from SOLTES is very good for the day evaluated.

  13. Information Systems Outsourcing Relationship Model

    Microsoft Academic Search

    Richard Flemming; Graham Low

    2007-01-01

    Increasing attention is being paid to what determines the success of an information systems outsourcing arrangement. The current research aims to provide an improved understanding of the factors influencing the outcome of an information systems outsourcing relationship and to provide a preliminary validation of an extended outsourcing relationship model by interviews with information systems outsourcing professionals in both the client

  14. Adaptive Patient Education Framework Featuring Personalized Cardiovascular Risk Management

    E-print Network

    Abidi, Syed Sibte Raza

    Adaptive Patient Education Framework Featuring Personalized Cardiovascular Risk Management Interventions Selena Davis and Syed Sibte Raza Abidi Health Informatics Laboratory, Faculty of Computer Science of cardiovascular risk. We present a web-based adaptive hypermedia system to create and deliver the personalized

  15. Does cardiovascular reactivity during speech reflect self-construction processes?

    Microsoft Academic Search

    A. C. Lyons; J. Spicer; K. Tuffin; K. Chamberlain

    2000-01-01

    Substantial empirical research has been undertaken on cardiovascular reactivity (CVR). however interpretation of this research is hampered by a lack of theoretical frameworks. This paper develops a framework initially stimulated by evidence demonstrating that the cardiovascular system increases in activity during communication, and that the extent of this activation depends upon numerous and diverse psychosocial factors. We attempt to account

  16. Cardiovascular and Cerebrovascular Control on Return from ISS

    NASA Technical Reports Server (NTRS)

    Hughson, Richard Lee; Shoemaker, Joel Kevin; Blaber, Andrew Philip; Arbeille, Philippe; Greaves, Danielle Kathleen

    2008-01-01

    Cardiovascular and Cerebrovascular Control on Return from ISS (CCISS) will study the effects of long-duration spaceflight on crew members' heart functions and their blood vessels that supply the brain. Learning more about the cardiovascular and cerebrovascular systems could lead to specific countermeasures that might better protect future space travelers. This experiment is collaborative with the Canadian Space Agency.

  17. [Nutrition and cardiovascular mortality].

    PubMed

    Fehér, János; Lengyel, Gabriella

    2006-08-13

    About 17 million persons die in cardiovascular disease yearly in the world. Most part of this disease can be prevented by the elimination of primary risk factors, thus by the abolishment of unhealthy nutrition, physical inactivity and by the absence of smoking. The cost-effective national program, as well as the life style with decreasing individual risk factors can give a trend to decrease the cardiovascular mortality. Individually the usual blood pressure and cholesterol control, the inhibition of obesity and the life style without smoking are able to decrease the organic changes, which produce the lethal consequences of this disease. The different kinds of diets can significantly influence the development of human diseases. The Western diet has atherogenic effect, increases the risk of myocardial infarction. The Mediterranean diet beneficially influences the life expectancy at birth. The Far-East Japanese diet could specially be important from the viewpoint of nutrition, because the longest life expectancy at birth and the smallest cardiovascular mortality can be found there. The quality nutrition factors (vitamins, vitamin like materials, polyphenols in wine and fruit juices, trace elements, omega-3 fatty acids) play an important role in the decreasing of oxidative stress and cardiovascular mortality. PMID:16981422

  18. Cardiovascular Health, Part 2

    PubMed Central

    Baman, Timir S.; Gupta, Sanjaya; Day, Sharlene M.

    2010-01-01

    Context: An athlete’s health may be endangered if he or she continues to compete after diagnosis of certain cardiovascular conditions. The most worrisome risk is sudden cardiac death; the annual rate in US athletes is 1 in 50 000 to 200 000. Evidence Acquisition: Part 2 of this review highlights the current guidelines and controversies surrounding compatibility of participation with a variety of cardiac conditions in competitive and recreational athletics. Data sources were limited to peer-reviewed publications from 1984 to the April 2009. Results: The guidelines published by the American College of Cardiology and the European Society of Cardiology provide a framework for safe competitive and recreational sports participation in athletes with a broad spectrum of inherited and acquired cardiovascular disorders. These guidelines are necessarily conservative because it is not currently possible to individualize risk prediction. Few data are available in many areas, particularly in the noncompetitive arena or in older athletes. Conclusions: Published national guidelines are currently the foundation governing return-to-play decisions in athletes with cardiovascular conditions. Further studies are needed to refine risk stratification algorithms to allow athletes with cardiovascular conditions to reap the health benefits of regular exercise and sports participation without undue risk. PMID:23015920

  19. Tomatoes and Cardiovascular Health

    Microsoft Academic Search

    Joye K. Willcox; George L. Catignani; Sheryl Lazarus

    2003-01-01

    Diet is believed to play a complex role in the development of cardiovascular disease, the leading cause of death in the Western world. Tomatoes, the second most produced and consumed vegetable nationwide, are a rich source of lycopene, beta-carotene, folate, potassium, vitamin C, flavonoids, and vitamin E. The processing of tomatoes may significantly affect the bioavailability of these nutrients. Homogenization,

  20. Cardiovascular sequelae of tobacco smoking.

    PubMed

    Rempher, Kenneth J

    2006-03-01

    Smoking is a known risk factor for cardiovascular disease and has been implicated in sudden cardiac death. Hypertension, hypercholesterolemia, physical inactivity, and smoking are the leading contributors to poor cardiovascular health. This article reviews the cardiovascular pathology inherent with smoking and provide insight to help develop an appropriate plan of care. PMID:16546004

  1. Emerging issues in radiogenic cataracts and cardiovascular disease.

    PubMed

    Hamada, Nobuyuki; Fujimichi, Yuki; Iwasaki, Toshiyasu; Fujii, Noriko; Furuhashi, Masato; Kubo, Eri; Minamino, Tohru; Nomura, Takaharu; Sato, Hitoshi

    2014-09-01

    In 2011, the International Commission on Radiological Protection issued a statement on tissue reactions (formerly termed non-stochastic or deterministic effects) to recommend lowering the threshold for cataracts and the occupational equivalent dose limit for the crystalline lens of the eye. Furthermore, this statement was the first to list circulatory disease (cardiovascular and cerebrovascular disease) as a health hazard of radiation exposure and to assign its threshold for the heart and brain. These changes have stimulated various discussions and may have impacts on some radiation workers, such as those in the medical sector. This paper considers emerging issues associated with cataracts and cardiovascular disease. For cataracts, topics dealt with herein include (i) the progressive nature, stochastic nature, target cells and trigger events of lens opacification, (ii) roles of lens protein denaturation, oxidative stress, calcium ions, tumor suppressors and DNA repair factors in cataractogenesis, (iii) dose rate effect, radiation weighting factor, and classification systems for cataracts, and (iv) estimation of the lens dose in clinical settings. Topics for cardiovascular disease include experimental animal models, relevant surrogate markers, latency period, target tissues, and roles of inflammation and cellular senescence. Future research needs are also discussed. PMID:24824673

  2. Prevalence of traditional cardiovascular risk factors in African-American women with systemic lupus erythematosus (SLE): findings from the breakfast with a buddy biomarkers of lupus study.

    PubMed

    Williams, Edith; Dorn, Joan; Crespo, Carlos

    2008-07-01

    African-American women are at high risk for systemic lupus erythematosus (SLE). Women with SLE are 5 to 8 times more likely to develop cardiovascular disease (CVD). The objective of this study was to characterize the prevalence of traditional CVD risk factors and the markers of sub-clinical atherosclerosis between African-American SLE cases (n=28) and controls (n=73). Significant differences were observed between SLE cases and controls in the areas of high blood pressure (68% of SLE cases, 42% of controls, p = 0.02), current smoking (18% of SLE cases, 15% of controls, p = 0.01), and average fasting glucose (85 mg/dL in SLE cases, 98 mg/dL in controls, p = 0.02). SLE cases displayed non-significantly higher HDL-c levels, lower LDL-c levels, and lower BMI. These results must be interpreted cautiously since the study sample was small and highly select. Larger studies are recommended to elucidate non-traditional mechanisms that may modulate some of the increased risk for CVD associated with SLE in women. PMID:18807776

  3. Coupling vascular and myocardial inflammatory injury into a common phenotype of cardiovascular dysfunction: systemic inflammation and aging - a mini-review.

    PubMed

    Puntmann, Valentina O; Taylor, Peter C; Mayr, Manuel

    2011-01-01

    The rising epidemic of cardiovascular (CV) disease is fuelled by obesity, hypertension and diabetes and, independently and cumulatively, by an aging population. Extensive research identified immunoinflammatory mechanisms as key drivers in the initiation and progression of the disease, from early asymptomatic stages of vascular and myocardial injury leading to the clinically manifest dysfunction and remodeling in advanced stages. Underlying processes include endothelial dysfunction and extracellular matrix restructuration leading to increased vascular stiffness, as well as myocardial remodeling with dilatation and wall thinning. In this, overproduction of tumor necrosis factor-?, amongst others, contributes to generalized CV injury and dysfunction. Moreover, recent insights into the involvement of innate and adaptive immunity in atherosclerosis have shed light on many interesting parallels with chronic systemic inflammatory conditions, such as rheumatoid arthritis, with aggravated inflammation-induced vascular and myocardial injury. Besides, chronologic age has been identified as a potent, independent risk for reduced CV capacity and a plethora of heart diseases, with other modifiable risk factors acting as accelerators. We discuss the available evidence and propose that characterization of inflammatory CV responses might reveal a distinctive CV inflammatory phenotype. A comprehensive noninvasive bio-signature, comprising immunomic biomarkers and integrated noninvasive imaging, may serve as a potential tool in the early diagnosis and prognostication of CV risk. PMID:20551624

  4. Long-term effect of prazosin and losartan administration on blood pressure, heart, carotid artery, and acetylcholine induced dilation of cardiovascular system of young Wistar rats and SHR.

    PubMed

    Kristek, Frantisek; Malekova, Magdalena; Cacanyiova, Sona

    2013-06-01

    The long-term effects of prazosin and losartan administration on blood pressure, trophicity of the heart and carotid arteries, and responses of the cardiovascular system to acetylcholine, were studied in Wistar rats and spontaneously hypertensive rats (SHRs). Four-week-old rats were treated with prazosin (10 mg/kg b.w./day in tap water) or losartan (20 mg/kg b.w./day in tap water) for 5-6 weeks. BP was measured by plethysmographic method. Ten animals of each group were subjected to in vivo studies and subsequent to morphological investigations. The right jugular vein was cannulated for administration of acetylcholine (0.1, 1, and 10 µg). After perfusion with a glutaraldehyde fixative (120 mmHg), the carotid arteries were embedded in Durcupan ACM, and the inner diameter (ID), wall thickness (WT) (tunica intima and media), cross sectional area (CSA) (tunica intima and media), and WT/ID ratio were calculated. In Wistar rats and SHRs, prazosin and losartan administration produced a decrease in the blood pressure and trophicity of the heart. In Wistar rats, both drugs decreased the WT, CSA, and the WT/ID ratio. In addition, these drugs increased the circumferential stress of the artery without affecting the ID. In contrast, in the SHRs, only losartan administration produced these effects. Importantly, both the drugs improved the responses to acetylcholine in SHRs. PMID:23682024

  5. Effects of acute and chronic sleep deprivation on cardiovascular regulation.

    PubMed

    Tobaldini, E; Pecis, M; Montano, N

    2014-09-01

    Sleep is a fundamental physiological process, characterized by the activation of several cortical and subcortical neural networks. The relation between sleep and cardiovascular system is complex and bidirectional: sleep disor- ders may alter cardiovascular system, leading to an increased cardiovascular risk, while, on the contrary, cardio- vascular diseases are characterized by an alteration of physiological sleep. Autonomic nervous system (ANS) plays a key role in the regulation of cardiovascular functions during different sleep stages, with sympatho-vagal balance dynamically shifting towards sympathetic or vagal predominance across different sleep stages. Sleep deprivation (SD) has becoming one of the most relevant health problem in modern societies. SD can be related to aging, which is associated with increased sleep fragmentation, and to sleep disorders, such as sleep disordered breathing and neurological disorders. Experimental studies in animals showed that SD significantly affects cardiovascular functions, altering heart rate and blood pressure responses, and increasing sympathetic activity and neuroendocrine response to stressor stimu- li. Clinical studies in humans have shown that SD, either due to experimental sleep loss and to sleep disorders, can affect different biological pathways, such as cardiovascular autonomic control, inflammation, immunity responses and metabolism. All these alterations may predispose subjects with SD to an increased cardiovascular risk. Hence, it is fundamental to identify the presence of a sleep disorder, which could be per se responsible for sleep loss, or the presence of sleep deprivation due to other factors, such as social life, habits etc., in order to identify subjects at high risk for cardiovascular events. PMID:25828682

  6. Pathophysiologic Mechanisms of Cardiovascular Disease in Obstructive Sleep Apnea Syndrome

    PubMed Central

    Zamarrón, Carlos; Valdés Cuadrado, Luis; Álvarez-Sala, Rodolfo

    2013-01-01

    Obstructive sleep apnea syndrome (OSAS) is a highly prevalent sleep disorder, characterized by repeated disruptions of breathing during sleep. This disease has many potential consequences including excessive daytime sleepiness, neurocognitive deterioration, endocrinologic and metabolic effects, and decreased quality of life. Patients with OSAS experience repetitive episodes of hypoxia and reoxygenation during transient cessation of breathing that provoke systemic effects. Furthermore, there may be increased levels of biomarkers linked to endocrine-metabolic and cardiovascular alterations. Epidemiological studies have identified OSAS as an independent comorbid factor in cardiovascular and cerebrovascular diseases, and physiopathological links may exist with onset and progression of heart failure. In addition, OSAS is associated with other disorders and comorbidities which worsen cardiovascular consequences, such as obesity, diabetes, and metabolic syndrome. Metabolic syndrome is an emerging public health problem that represents a constellation of cardiovascular risk factors. Both OSAS and metabolic syndrome may exert negative synergistic effects on the cardiovascular system through multiple mechanisms (e.g., hypoxemia, sleep disruption, activation of the sympathetic nervous system, and inflammatory activation). It has been found that CPAP therapy for OSAS provides an objective improvement in symptoms and cardiac function, decreases cardiovascular risk, improves insulin sensitivity, and normalises biomarkers. OSAS contributes to the pathogenesis of cardiovascular disease independently and by interaction with comorbidities. The present review focuses on indirect and direct evidence regarding mechanisms implicated in cardiovascular disease among OSAS patients. PMID:23936649

  7. Blood flow mechanics in cardiovascular development.

    PubMed

    Boselli, Francesco; Freund, Jonathan B; Vermot, Julien

    2015-07-01

    Hemodynamic forces are fundamental to development. Indeed, much of cardiovascular morphogenesis reflects a two-way interaction between mechanical forces and the gene network activated in endothelial cells via mechanotransduction feedback loops. As these interactions are becoming better understood in different model organisms, it is possible to identify common mechanogenetic rules, which are strikingly conserved and shared in many tissues and species. Here, we discuss recent findings showing how hemodynamic forces potentially modulate cardiovascular development as well as the underlying fluid and tissue mechanics, with special attention given to the flow characteristics that are unique to the small scales of embryos. PMID:25801176

  8. Stochastic models of chaotic systems

    SciTech Connect

    Leith, C.E.

    1995-09-01

    Nonlinear dynamical systems, although strictly deterministic, often exhibit chaotic behavior which appears to be random. The determination of the probabilistic properties of such systems is, in general, an open problem. Closure approximations for moment expansion methods have been unsatisfactory. More successful has been approximation on the dynamics level by the use of linear stochastic models that attempt to generate the probabilistic properties of the original nonlinear chaotic system as closely as possible. Examples are reviewed of this approach to simple nonlinear systems, to turbulence, and to large-eddy simulation. A stochastic model that simulates the transient energy spectrum of the global atmosphere is developed.

  9. The Cardiovascular Physiology of Sports and Exercise.

    PubMed

    Opondo, Mildred A; Sarma, Satyam; Levine, Benjamin D

    2015-07-01

    Athletes represent the extremes of human performance. Many of their remarkable abilities stem from a cardiovascular system that has adapted to meet the metabolic needs of exercising muscle. A large and compliant heart is a hallmark feature of athletes who engage in highly aerobic events. Despite high fitness levels, athletes may present with symptoms that limit performance. Understanding and dissecting these limitations requires a strong background in sports science and the factors that determine sports capabilities. This article reviews the basic principles of exercise physiology, cardiovascular adaptations unique to the "athlete's heart," and the utility of exercise testing in athletes. PMID:26100417

  10. Metabolic biomarkers for predicting cardiovascular disease

    PubMed Central

    Montgomery, Jana E; Brown, Jeremiah R

    2013-01-01

    Cardiac and peripheral vascular biomarkers are increasingly becoming targets of both research and clinical practice. As of 2008, cardiovascular-related medical care accounts for greater than 20% of all the economic costs of illness in the United States. In the age of burgeoning financial pressures on the entire health care system, never has it been more important to try to understand who is at risk for cardiovascular disease in order to prevent new events. In this paper, we will discuss the cost of cardiovascular disease to society, clarify the definition of and need for biomarkers, offer an example of a current biomarker, namely high-sensitivity C-reactive protein, and finally examine the approval process for utilizing these in clinical practice. PMID:23386789

  11. Preparing nurses for leadership roles in cardiovascular disease prevention.

    PubMed

    Lanuza, Dorothy M; Davidson, Patricia M; Dunbar, Sandra B; Hughes, Suzanne; De Geest, Sabina

    2011-07-01

    Cardiovascular disease (CVD) is a critical global health issue, and cardiovascular nurses play a vital role in decreasing the global burden and contributing to improving outcomes in individuals and communities. Cardiovascular nurses require the knowledge, skills, and resources that will enable them to function as leaders in CVD. This article addresses the education, training, and strategies that are needed to prepare nurses for leadership roles in preventing and managing CVD. Building on the World Health Organization core competencies for 21st-century health care workers, the specific competencies of cardiovascular nurses working in prevention are outlined. These can be further strengthened by investing in the development of cultural, system change and leadership competencies. Mentorship is proposed as a powerful strategy for promoting the cardiovascular nursing role and equipping individual nurses to contribute meaningfully to health system reform and community engagement in CVD risk reduction. PMID:21762853

  12. Preparing nurses for leadership roles in cardiovascular disease prevention.

    PubMed

    Lanuza, Dorothy M; Davidson, Patricia M; Dunbar, Sandra B; Hughes, Suzanne; De Geest, Sabina

    2011-01-01

    Cardiovascular disease (CVD) is a critical global health issue, and cardiovascular nurses play a vital role in decreasing the global burden and contributing to improving outcomes in individuals and communities. Cardiovascular nurses require the knowledge, skills, and resources that will enable them to function as leaders in CVD. This article addresses the education, training, and strategies that are needed to prepare nurses for leadership roles in preventing and managing CVD. Building on the World Health Organization core competencies for 21st-century health care workers, the specific competencies of cardiovascular nurses working in prevention are outlined. These can be further strengthened by investing in the development of cultural, system change and leadership competencies. Mentorship is proposed as a powerful strategy for promoting the cardiovascular nursing role and equipping individual nurses to contribute meaningfully to health system reform and community engagement in CVD risk reduction. PMID:21659815

  13. CVSim: An Open-Source Cardiovascular Simulator for Teaching and Research

    PubMed Central

    Heldt, Thomas; Mukkamala, Ramakrishna; Moody, George B.; Mark, Roger G.

    2011-01-01

    CVSim is a lumped-parameter model of the human cardiovascular system that has been developed and used for research and for teaching quantitative physiology courses at MIT and Harvard Medical School since 1984. We present a brief historical background of lumped-parameter cardiovascular system models, followed by an overview of the development of the major versions of CVSim over a 25-year period in our laboratory. We describe the features and differences of four versions of CVSim that are freely available in open-source form via PhysioNet (http://physionet.org). These include a six-compartment cardiovascular model with an arterial baroreflex system, implemented in C for efficiency, with an X-based graphical user interface; a six-compartment model with a more extensive short-term regulatory system and incorporating resting physiologic perturbations, available as a stand-alone MATLAB application; and a pair of elaborated versions consisting of 6- and 21-compartment computational models implemented in C, with a separate and enhanced Java graphical user interface. We conclude with a discussion of the educational and research applications for which we have used CVSim. PMID:21949555

  14. Model systems in neurotoxicology

    SciTech Connect

    Shahar, A. (Israel Institute for Biological Research, Ness-Ziona, (IL)); Goldberg, A.M. (Johns Hopkins, Univ., Baltimore, MD (US))

    1987-01-01

    This book contains 33 papers. Some of the titles are: Establishment of cell lines from primary cultures by transfection with SV40 large T antigen gene; Molecular cloning of human cholinesterase genes: Potential applications in neurotoxicology; Neurotoxicity testing of chlorinated hydrocarbons by measuring specific neuronal and glial cell functions; Genetic and pharmacological models of muscle inactivity; and Overexpression of the human CuZnSOD gene in transfected cells: Implication to Down Syndrome.

  15. A FLUID-CELL INTERACTION AND ADHESION ALGORITHM FOR TISSUE-COATING OF CARDIOVASCULAR IMPLANTS

    E-print Network

    Canic, Suncica

    A FLUID-CELL INTERACTION AND ADHESION ALGORITHM FOR TISSUE-COATING OF CARDIOVASCULAR IMPLANTS JIAN and adhesion algorithm applied to modeling the cell coating of artificial surfaces of cardiovascular implants describing cell coating of cardiovascular implants are presented in Section 2. To study this problem we

  16. Cardiac repair in a porcine model of acute myocardial infarction with human induced pluripotent stem cell-derived cardiovascular cells.

    PubMed

    Ye, Lei; Chang, Ying-Hua; Xiong, Qiang; Zhang, Pengyuan; Zhang, Liying; Somasundaram, Porur; Lepley, Mike; Swingen, Cory; Su, Liping; Wendel, Jacqueline S; Guo, Jing; Jang, Albert; Rosenbush, Daniel; Greder, Lucas; Dutton, James R; Zhang, Jianhua; Kamp, Timothy J; Kaufman, Dan S; Ge, Ying; Zhang, Jianyi

    2014-12-01

    Human induced pluripotent stem cells (hiPSCs) hold promise for myocardial repair following injury, but preclinical studies in large animal models are required to determine optimal cell preparation and delivery strategies to maximize functional benefits and to evaluate safety. Here, we utilized a porcine model of acute myocardial infarction (MI) to investigate the functional impact of intramyocardial transplantation of hiPSC-derived cardiomyocytes, endothelial cells, and smooth muscle cells, in combination with a 3D fibrin patch loaded with insulin growth factor (IGF)-encapsulated microspheres. hiPSC-derived cardiomyocytes integrated into host myocardium and generated organized sarcomeric structures, and endothelial and smooth muscle cells contributed to host vasculature. Trilineage cell transplantation significantly improved left ventricular function, myocardial metabolism, and arteriole density, while reducing infarct size, ventricular wall stress, and apoptosis without inducing ventricular arrhythmias. These findings in a large animal MI model highlight the potential of utilizing hiPSC-derived cells for cardiac repair. PMID:25479750

  17. RIGOROUS MODELING AND SIMULATION OF MECHATRONIC SYSTEMS

    E-print Network

    Taylor, James H.

    RIGOROUS MODELING AND SIMULATION OF MECHATRONIC SYSTEMS James H. Taylor Professor Emeritus, Systems on mechatronic systems. Emphasis is placed on rigorous techniques and selecting the most appropriate method mentioned above for mechatronic systems. Key Words: Mechatronic systems, modeling, simulation, numerical

  18. Cardiovascular Simulator for the Undergraduate Physics Laboratory.

    ERIC Educational Resources Information Center

    Bruner, L. J.

    1979-01-01

    Described is a cardiovascular simulator which illustrates the use of a catheter-coupled external transducer for dynamic pressure measurements in the circulatory system. With the simulator, students can observe the effects of stroke volume and rate upon maximum, minimum, and mean arterial pressure. (Author/GA)

  19. Human cardiovascular responses to passive heat stress.

    PubMed

    Crandall, Craig G; Wilson, Thad E

    2015-01-01

    Heat stress increases human morbidity and mortality compared to normothermic conditions. Many occupations, disease states, as well as stages of life are especially vulnerable to the stress imposed on the cardiovascular system during exposure to hot ambient conditions. This review focuses on the cardiovascular responses to heat stress that are necessary for heat dissipation. To accomplish this regulatory feat requires complex autonomic nervous system control of the heart and various vascular beds. For example, during heat stress cardiac output increases up to twofold, by increases in heart rate and an active maintenance of stroke volume via increases in inotropy in the presence of decreases in cardiac preload. Baroreflexes retain the ability to regulate blood pressure in many, but not all, heat stress conditions. Central hypovolemia is another cardiovascular challenge brought about by heat stress, which if added to a subsequent central volumetric stress, such as hemorrhage, can be problematic and potentially dangerous, as syncope and cardiovascular collapse may ensue. These combined stresses can compromise blood flow and oxygenation to important tissues such as the brain. It is notable that this compromised condition can occur at cardiac outputs that are adequate during normothermic conditions but are inadequate in heat because of the increased systemic vascular conductance associated with cutaneous vasodilation. Understanding the mechanisms within this complex regulatory system will allow for the development of treatment recommendations and countermeasures to reduce risks during the ever-increasing frequency of severe heat events that are predicted to occur. PMID:25589263

  20. DIETARY EFFECTS OF CARDIOVASCULAR RISK FACTORS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the beginning of the 21st century, as in the latter half of the 20th century, diseases of the cardiovascular system are the leading cause of death and disability in developed counties. In 2004, a report from the World Health Organization sounded the alarm, indicating that countries in transition ...

  1. Systems Biology: Models and Logics

    Microsoft Academic Search

    Carla Piazza; Alberto Policriti

    2008-01-01

    The field of systems biology focuses on creating a finely detailed picture of biological mechanisms. Recently, the need has\\u000a arisen for more and more sophisticated and mathematically well founded computational tools, capable of analyzing those models\\u000a that are and will be at the core of Systems Biology. The challenge consists in faithfully implementing such computational\\u000a models in software packages exploiting

  2. Slow breathing and cardiovascular disease.

    PubMed

    Chaddha, Ashish

    2015-01-01

    Cardiovascular disease is the leading cause of death for both men and women worldwide. Much emphasis has been placed on the primary and secondary prevention of cardiovascular disease. While depression and anxiety increase the risk of developing cardiovascular disease, cardiovascular disease also increases the risk of developing anxiety and depression. Thus, promoting optimal mental health may be important for both primary and secondary prevention of cardiovascular disease. Like lowering blood pressure, lipids, and body weight, lowering anger and hostility and improving depression and anxiety may also be an important intervention in preventive cardiology. As we strive to further improve cardiovascular outcomes, the next bridge to cross may be one of offering patients nonpharmacologic means for combating daily mental stress and promoting mental health, such as yoga and pranayama. Indeed, the best preventive cardiovascular medicine may be a blend of both Western and Eastern medicine. PMID:26170595

  3. Status of cardiovascular issues related to space flight: Implications for future research directions

    Microsoft Academic Search

    Victor A. Convertino

    2009-01-01

    Compromised cardiovascular performance, occurrence of serious cardiac dysrhythmias, cardiac atrophy, orthostatic intolerance, reduced aerobic capacity, operational impacts of regular physical exercise, and space radiation are risks of space flight to the cardiovascular system identified in the 2007 NASA Human Integrated Research Program. An evidence-based approach to identify the research priorities needed to resolve those cardiovascular risks that could most likely

  4. Factors Predicting Nutrition and Physical Activity Behaviors Due to Cardiovascular Disease in Tehran University Students: Application of Health Belief Model

    PubMed Central

    Rahmati-Najarkolaei, Fatemeh; Tavafian, Sedigheh Sadat; Gholami Fesharaki, Mohammad; Jafari, Mohammad Reza

    2015-01-01

    Background: Disease preventing methods focus mostly on lifestyle factors such as physical activity, healthy diet and not smoking. Previous studies verified using theory and models to change unhealthy behaviors, so that health belief model (HBM) is a useful framework for describing the healthy nutrition behavior. Objectives: This study aimed to predict factors related to unhealthy nutrition and inactive life in students of Tehran University, Tehran, Iran based on the Health Belief Model (HBM). Patients and Methods: In this cross sectional study, proportional quota sampling from three different educational levels was conducted from October to December 2012. A self-administered validated instrument based on the Health Belief Model (HBM) with 69 items and four sections was used to collect data. In this study through using linear and logistic regression, the effect of body mass index, age, gender, marriage, self-efficacy, cues to action, knowledge, perceived severity, susceptibility, benefits and barriers on nutrition and physical activity behavior were assessed. SPSS version 18 was used to analyze data. Results: Totally, 368 students including 318 female students (86.4%) and 50 male students (13.6%) with a mean age of 24.9 years (SD = 4.55) took part in the study. Among all independent variables, gender (P < 0.001), knowledge (P = 0.023) and perceived barriers (P = 0.004) predicted nutrition behavior. In case of physical activity, knowledge (P = 0.011), perceived severity (P = 0.009), perceived barriers (P = 0.019) and self-efficacy (P = 0.033) had significance association with physical activity behavior. Conclusions: This study indicated that health belief model contrasts could predict the risky behavior of university students due to heart disease. However, more researches are needed to verify the predictors of high risky behaviors in students. PMID:26019896

  5. WATER QUALITY MODELING DISTRIBUTION SYSTEMS

    EPA Science Inventory

    This paper reviews the use of models for predicting water quality in distribution systems. esults of an extensive field study conducted by the USEPA and North Penn Mater Authority are examined. A case study of the model application to a waterborne disease outbreak in Cabool, Miss...

  6. Altered TGF? signaling and cardiovascular manifestations in patients with autosomal recessive cutis laxa type I caused by fibulin-4 deficiency

    Microsoft Academic Search

    Marjolijn Renard; Tammy Holm; Regan Veith; Bert L Callewaert; Lesley C Adès; Osman Baspinar; Angela Pickart; Majed Dasouki; Juliane Hoyer; Anita Rauch; Pamela Trapane; Michael G Earing; Paul J Coucke; Lynn Y Sakai; Harry C Dietz; Anne M De Paepe; Bart L Loeys

    2010-01-01

    Fibulin-4 is a member of the fibulin family, a group of extracellular matrix proteins prominently expressed in medial layers of large veins and arteries. Involvement of the FBLN4 gene in cardiovascular pathology was shown in a murine model and in three patients affected with cutis laxa in association with systemic involvement. To elucidate the contribution of FBLN4 in human disease,

  7. A model of reservation systems

    Microsoft Academic Search

    Jorma T. Virtamo

    1992-01-01

    The author considers the performance evaluation of an advanced capacity reservation system using the CCITT defined reserved call establishment mode. A simple model for the traffic process is introduced: calls are assumed to be offered uniformly to the reservation book. The state of the system can then be described statistically in terms of the population of various types of islands

  8. Transgenerational Epigenetics: The Role of Maternal Effects in Cardiovascular Development

    PubMed Central

    Ho, Dao H.

    2014-01-01

    Transgenerational epigenetics, the study of non-genetic transfer of information from one generation to the next, has gained much attention in the past few decades due to the fact that, in many instances, epigenetic processes outweigh direct genetic processes in the manifestation of aberrant phenotypes across several generations. Maternal effects, or the influences of maternal environment, phenotype, and/or genotype on offsprings’ phenotypes, independently of the offsprings’ genotypes, are a subcategory of transgenerational epigenetics. Due to the intimate role of the mother during early development in animals, there is much interest in investigating the means by which maternal effects can shape the individual. Maternal effects are responsible for cellular organization, determination of the body axis, initiation and maturation of organ systems, and physiological performance of a wide variety of species and biological systems. The cardiovascular system is the first to become functional and can significantly influence the development of other organ systems. Thus, it is important to elucidate the role of maternal effects in cardiovascular development, and to understand its impact on adult cardiovascular health. Topics to be addressed include: (1) how and when do maternal effects change the developmental trajectory of the cardiovascular system to permanently alter the adult’s cardiovascular phenotype, (2) what molecular mechanisms have been associated with maternally induced cardiovascular phenotypes, and (3) what are the evolutionary implications of maternally mediated changes in cardiovascular phenotype? PMID:24813463

  9. Model Course: Microcomputer Operating Systems

    NSDL National Science Digital Library

    This site includes a model course from the CyberWatch Center. The site does not currently include any educational materials, but does provide a model framework for structuring a course on this topic. The course aims to help students learn more about DOS and Windows operating environments, including basic and advanced operations and use of system utilities. Topics include common system utilities, creating and editing text files, GUI environments, creating application shortcuts and other useful skills. A detailed course outline is included. Users must register to view the model course, but registration is free and easy.

  10. Translating metabolomics to cardiovascular biomarkers.

    PubMed

    Senn, Todd; Hazen, Stanley L; Tang, W H Wilson

    2012-01-01

    Metabolomics is the systematic study of the unique chemical fingerprints of small molecules or metabolite profiles that are related to a variety of cellular metabolic processes in a cell, organ, or organism. Although messenger RNA gene expression data and proteomic analyses do not tell the whole story of what might be happening in a cell, metabolic profiling provides direct and indirect physiologic insights that can potentially be detectable in a wide range of biospecimens. Although not specific to cardiac conditions, translating metabolomics to cardiovascular biomarkers has followed the traditional path of biomarker discovery from identification and confirmation to clinical validation and bedside testing. With technological advances in metabolomic tools (such as nuclear magnetic resonance spectroscopy and mass spectrometry) and more sophisticated bioinformatics and analytical techniques, the ability to measure low-molecular-weight metabolites in biospecimens provides a unique insight into established and novel metabolic pathways. Systemic metabolomics may provide physiologic understanding of cardiovascular disease states beyond traditional profiling and may involve descriptions of metabolic responses of an individual or population to therapeutic interventions or environmental exposures. PMID:22824112

  11. Thiazolidinediones and cardiovascular disease

    Microsoft Academic Search

    Robert Chilton; Elaine Chiquette

    2005-01-01

    Thiazolidinediones hold promise for reducing cardiovascular events and human atherosclerosis. Similar to statins and angiotensin-converting\\u000a enzyme inhibitors, peroxisome proliferator activated receptor ? (PPAR?) exerts anti-inflammatory and antiatherosclerotic actions\\u000a in the vessel wall. A number of clinical trials in subjects with or without diabetes have shown that thiazolidinedione therapy\\u000a can reduce in-stent restenosis and delay progression of atherosclerosis measured by carotid

  12. Phytoestrogens and Cardiovascular Disorders

    Microsoft Academic Search

    Ricky Y. K. Man; Susan W. S. Leung; Hwee Teoh; Adrian Quan; Wendy Keung; Mary Y. K. Lee

    \\u000a Dietary intake of phytoestrogens has been associated with a reduction in risk of cardiovascular disorders including coronary\\u000a heart disease, hypertension and atherosclerosis. Phytoestrogens have long been found to be structurally similar to the female\\u000a sex hormone, 17ß-estradiol, and have a wide range of estrogenic effects. Like 17ß-estradiol, phytoestrogens such as genistein\\u000a have been suggested to exert its cardioprotective actions through

  13. Time to re-evaluate effects of renin-angiotensin system inhibitors on renal and cardiovascular outcomes in diabetic nephropathy.

    PubMed

    Suzuki, Hiromichi; Kikuta, Tomohiro; Inoue, Tsutomu; Hamada, Ukihiro

    2015-02-01

    The use of renin-angiotensin system (RAS) inhibitors, such angiotensin converting enzyme inhibitors/angiotensin-II receptor blockers, to slow progression of chronic kidney disease (CKD) in a large group dominated by elderly people in the real world is not supported by available evidence. Large-scale clinical trials had many faults, among them a lack of focus on the elderly. However, it would be difficult to conduct clinical trials of a similar scale in elderly CKD patients. Besides, progression of kidney disease is often slow in elderly persons, and the vast majority of older adults with CKD will die before reaching end stage renal disease. Moreover, since it is not clear that progression of kidney disease, and even of proteinuric diabetic nephropathy, is not inhibited through the use of RAS inhibitors, the most patient-centric goal of therapy for many elderly individuals should be individualized. PMID:25664254

  14. Cardiovascular Deconditioning in Humans: Human Studies Core

    NASA Technical Reports Server (NTRS)

    Williams, Gordon

    1999-01-01

    Major cardiovascular problems, secondary to cardiovascular deconditioning, may occur on extended space missions. While it is generally assumed that the microgravity state is the primary cause of cardiovascular deconditioning, sleep deprivation and disruption of diurnal rhythms may also play an important role. Factors that could be modified by either or both of these perturbations include: autonomic function and short-term cardiovascular reflexes, vasoreactivity, circadian rhythm of cardiovascular hormones (specifically the renin-angiotensin system) and renal sodium handling and hormonal influences on that process, venous compliance, cardiac mass, and cardiac conduction processes. The purpose of the Human Studies Core is to provide the infrastructure to conduct human experiments which will allow for the assessment of the likely role of such factors in the space travel associated cardiovascular deconditioning process and to develop appropriate countermeasures. The Core takes advantage of a newly-created Intensive Physiologic Monitoring (IPM) Unit at the Brigham and Women's Hospital, Boston, MA, to perform these studies. The Core includes two general experimental protocols. The first protocol involves a head down tilt bed-rest study to simulate microgravity. The second protocol includes the addition of a disruption of circadian rhythms to the simulated microgravity environment. Before and after each of these environmental manipulations, the subjects will undergo acute stressors simulating changes in volume and/or stress, which could occur in space and on return to Earth. The subjects are maintained in a rigidly controlled environment with fixed light/dark cycles, activity pattern, and dietary intake of nutrients, fluids, ions and calories.

  15. Moderate inappropriately high aldosterone/NaCl constellation in mice: cardiovascular effects and the role of cardiovascular epidermal growth factor receptor.

    PubMed

    Schreier, Barbara; Rabe, Sindy; Winter, Sabrina; Ruhs, Stefanie; Mildenberger, Sigrid; Schneider, Bettina; Sibilia, Maria; Gotthardt, Michael; Kempe, Sabine; Mäder, Karsten; Grossmann, Claudia; Gekle, Michael

    2014-01-01

    Non-physiological activation of the mineralocorticoid receptor (MR), e.g. by aldosterone under conditions of high salt intake, contributes to the pathogenesis of cardiovascular diseases, although beneficial effects of aldosterone also have been described. The epidermal growth factor receptor (EGFR) contributes to cardiovascular alterations and mediates part of the MR effects. Recently, we showed that EGFR is required for physiological homeostasis and function of heart and arteries in adult animals. We hypothesize that moderate high aldosterone/NaCl, at normal blood pressure, affects the cardiovascular system depending on cardiovascular EGFR. Therefore we performed an experimental series in male and female animals each, using a recently established mouse model with EGFR knockout in vascular smooth muscle cells and cardiomyocytes and determined the effects of a mild-high aldosterone-to-NaCl constellation on a.o. marker gene expression, heart size, systolic blood pressure, impulse conduction and heart rate. Our data show that (i) cardiac tissue of male but not of female mice is sensitive to mild aldosterone/NaCl treatment, (ii) EGFR knockout induces stronger cardiac disturbances in male as compared to female animals and (iii) mild aldosterone/NaCl treatment requires the EGFR in order to disturb cardiac tissue homeostasis whereas beneficial effects of aldosterone seem to be independent of EGFR. PMID:25503263

  16. Moderate inappropriately high aldosterone/NaCl constellation in mice: cardiovascular effects and the role of cardiovascular epidermal growth factor receptor

    PubMed Central

    Schreier, Barbara; Rabe, Sindy; Winter, Sabrina; Ruhs, Stefanie; Mildenberger, Sigrid; Schneider, Bettina; Sibilia, Maria; Gotthardt, Michael; Kempe, Sabine; Mäder, Karsten; Grossmann, Claudia; Gekle, Michael

    2014-01-01

    Non-physiological activation of the mineralocorticoid receptor (MR), e.g. by aldosterone under conditions of high salt intake, contributes to the pathogenesis of cardiovascular diseases, although beneficial effects of aldosterone also have been described. The epidermal growth factor receptor (EGFR) contributes to cardiovascular alterations and mediates part of the MR effects. Recently, we showed that EGFR is required for physiological homeostasis and function of heart and arteries in adult animals. We hypothesize that moderate high aldosterone/NaCl, at normal blood pressure, affects the cardiovascular system depending on cardiovascular EGFR. Therefore we performed an experimental series in male and female animals each, using a recently established mouse model with EGFR knockout in vascular smooth muscle cells and cardiomyocytes and determined the effects of a mild-high aldosterone-to-NaCl constellation on a.o. marker gene expression, heart size, systolic blood pressure, impulse conduction and heart rate. Our data show that (i) cardiac tissue of male but not of female mice is sensitive to mild aldosterone/NaCl treatment, (ii) EGFR knockout induces stronger cardiac disturbances in male as compared to female animals and (iii) mild aldosterone/NaCl treatment requires the EGFR in order to disturb cardiac tissue homeostasis whereas beneficial effects of aldosterone seem to be independent of EGFR. PMID:25503263

  17. Modeling an Operating System Kernel

    NASA Astrophysics Data System (ADS)

    Börger, Egon; Craig, Iain

    We define a high-level model of an operating system (OS) kernel which can be refined to concrete systems in various ways, reflecting alternative design decisions. We aim at an exposition practitioners and lecturers can use effectively to communicate (document and teach) design ideas for operating system functionality at a conceptual level. The operational and rigorous nature of our definition provides a basis for the practitioner to validate and verify precisely stated system properties of interest, thus helping to make OS code reliable. As a by-product we introduce a novel combination of parallel and interruptable sequential Abstract State Machine steps.

  18. Protocol for the modeling the epidemiologic transition study: a longitudinal observational study of energy balance and change in body weight, diabetes and cardiovascular disease risk

    PubMed Central

    2011-01-01

    Background The prevalence of obesity has increased in societies of all socio-cultural backgrounds. To date, guidelines set forward to prevent obesity have universally emphasized optimal levels of physical activity. However there are few empirical data to support the assertion that low levels of energy expenditure in activity is a causal factor in the current obesity epidemic are very limited. Methods/Design The Modeling the Epidemiologic Transition Study (METS) is a cohort study designed to assess the association between physical activity levels and relative weight, weight gain and diabetes and cardiovascular disease risk in five population-based samples at different stages of economic development. Twenty-five hundred young adults, ages 25-45, were enrolled in the study; 500 from sites in Ghana, South Africa, Seychelles, Jamaica and the United States. At baseline, physical activity levels were assessed using accelerometry and a questionnaire in all participants and by doubly labeled water in a subsample of 75 per site. We assessed dietary intake using two separate 24-hour recalls, body composition using bioelectrical impedance analysis, and health history, social and economic indicators by questionnaire. Blood pressure was measured and blood samples collected for measurement of lipids, glucose, insulin and adipokines. Full examination including physical activity using accelerometry, anthropometric data and fasting glucose will take place at 12 and 24 months. The distribution of the main variables and the associations between physical activity, independent of energy intake, glucose metabolism and anthropometric measures will be assessed using cross-section and longitudinal analysis within and between sites. Discussion METS will provide insight on the relative contribution of physical activity and diet to excess weight, age-related weight gain and incident glucose impairment in five populations' samples of young adults at different stages of economic development. These data should be useful for the development of empirically-based public health policy aimed at the prevention of obesity and associated chronic diseases. PMID:22168992

  19. Effects of Emotional Stimuli on Cardiovascular Responses in Patients with Essential Hypertension Based on Brain/Behavioral Systems

    PubMed Central

    Taban Sadeghi, Mohammadreza; Namdar, Hossein; Vahedi, Shahram; Aslanabadi, Naser; Ezzati, Davoud; Sadeghi, Babak

    2013-01-01

    Introduction: Effects of emotional stimuli on hemodynamics in patients with essential hypertension based on brain/behavioral systems have not been studied broadly. Methods: Eighty five essential hypertensive male patients who had completed Carver-White BIS/BAS scale were enrolled to the study. Later, 25 BIS and 25 BAS patients were selected and their blood pressure and heart rate were recorded prior to stimuli induction. Participants were then exposed to stressor pictures. After that, 15 minutes of relaxation and cognitive tasks were performed. Finally, the participants were exposed to pleasant pictures. The blood pressure and heart rate were recorded after presenting of 2 stimuli. Results: Our study showed that BIS patients achieved higher scores in diastolic blood pressure and heart rate in comparison with BAS patients after presenting stressful stimuli. Also, BAS patients achieved lower scores in systolic blood pressure and heart rate in comparison with BIS patients after presenting pleasant stimuli. Conclusion: In summary, BIS patients experience negative emotions more than BAS patients. Therefore, the role of induced mood states is important in relation to physical health. PMID:24404349

  20. Arsenic exposure and cardiovascular disorders: an overview.

    PubMed

    Balakumar, Pitchai; Kaur, Jagdeep

    2009-12-01

    The incidence of arsenic toxicity has been observed in various countries including Taiwan, Bangladesh, India, Argentina, Australia, Chile, China, Hungary, Peru, Thailand, Mexico and United States of America. Arsenic is a ubiquitous element present in drinking water, and its exposure is associated with various cardiovascular disorders. Arsenic exposure plays a key role in the pathogenesis of vascular endothelial dysfunction as it inactivates endothelial nitric oxide synthase, leading to reduction in the generation and bioavailability of nitric oxide. In addition, the chronic arsenic exposure induces high oxidative stress, which may affect the structure and function of cardiovascular system. Further, the arsenic exposure has been noted to induce atherosclerosis by increasing the platelet aggregation and reducing fibrinolysis. Moreover, arsenic exposure may cause arrhythmia by increasing the QT interval and accelerating the cellular calcium overload. The chronic exposure to arsenic upregulates the expression of tumor necrosis factor-alpha, interleukin-1, vascular cell adhesion molecule and vascular endothelial growth factor to induce cardiovascular pathogenesis. The present review critically discussed the detrimental role of arsenic in the cardiovascular system. PMID:19787300

  1. Cardiovascular Risk in Women With PCOS

    PubMed Central

    Scicchitano, Pietro; Dentamaro, Ilaria; Carbonara, Rosa; Bulzis, Gabriella; Dachille, Annamaria; Caputo, Paola; Riccardi, Roberta; Locorotondo, Manuela; Mandurino, Cosimo; Matteo Ciccone, Marco

    2012-01-01

    Polycystic ovary syndrome (PCOS), or Stein-Leventhal syndrome, is a common endocrine disorder defined by two of the three following features: i) oligoovulation or anovulation, ii) clinical and/or biochemical signs of hyperandrogenism, or iii) polycystic ovaries, once the related endocrinological and gynaecological disorders have been excluded. PCOS does not exclusively involve the reproductive apparatus , it has a complex number of systemic relevancy symptoms. It leads to Metabolic Syndrome, with severe consequences on the cardiovascular apparatus. Many clinical studies have underlined the connection between PCOS and the cardiovascular risk profile of such female patients, due to a lipid/glucose altered metabolism, hypertension, systemic inflammatory condition (assessable by markers such as VES, TNF-alfa, citokines and C-reactive protein (hsPCR) levels), and vascular injuries. Considering the early onset of the disease, PCOS could be considered as a real cardiovascular risk factor which affects the quality of life seriously. The current review aimed to point out the main connections between PCOS and cardiovascular risk factors according to the latest findings coming from literature data analysis, and try to depict the great influences that such a common disease can have on the patients’ health integrity. PMID:23843832

  2. CARDIOVASCULAR AND BLOOD COAGULATION EFFECTS OF PULMONARY ZINC EXPOSURE

    EPA Science Inventory

    Cardiovascular damage induced by pulmonary exposure to environmental chemicals can result from direct action or, secondarily, from pulmonary injury. We have developed a rat model of pulmonary exposure to zinc to demonstrate cardiac, coagulative, and fibrinolytic alterations. Mal...

  3. Role of toll-like receptors in cardiovascular diseases.

    PubMed

    Vallejo, Jesus G

    2011-07-01

    The discovery and characterization of the TLR (Toll-like receptor) family has led to a better understanding of the innate immune system. The strategy of innate immune recognition is based on the detection of constitutive and conserved products of micro-organisms. However, host molecules that are released during injury can also activate TLRs. Engagement of TLRs by microbial or host-derived molecules induces the expression of pro-inflammatory cytokines, which may have both beneficial and detrimental effects on the host. In addition to being expressed in immune cells, TLRs are expressed in other tissues such as those of the cardiovascular system. In the present review, the role of TLRs in septic cardiomyopathy, viral myocarditis, atherosclerosis, ischaemia/reperfusion injury and cardiac remodelling after myocardial infarction are outlined, with attention paid to genetically modified murine models. Although much has been learned about stress-induced TLR activation in the tissues of the cardiovascular system, the role of individual TLRs in initiating and integrating homoeostatic responses within the heart remains to be defined. Accumulating evidence indicates that TLRs may play an important role in the pathogenesis of atherosclerosis, viral myocarditis, dilated cardiomyopathy, cardiac allograft rejection and sepsis-induced left ventricular dysfunction. Moreover, heart failure of diverse aetiology is also now recognized to have an important immune component, with TLR signalling influencing the process of cardiac remodelling and prognosis. In the present review, we outline the biology of TLRs as well as the current experimental and clinical evidence for the role of TLRs in cardiovascular diseases. PMID:21413930

  4. Obesity reduces left ventricular strains, torsion, and synchrony in mouse models: a cine displacement encoding with stimulated echoes (DENSE) cardiovascular magnetic resonance study

    PubMed Central

    2013-01-01

    Background Obesity affects a third of adults in the US and results in an increased risk of cardiovascular mortality. While the mechanisms underlying this increased risk are not well understood, animal models of obesity have shown direct effects on the heart such as steatosis and fibrosis, which may affect cardiac function. However, the effect of obesity on cardiac function in animal models is not well-defined. We hypothesized that diet-induced obesity in mice reduces strain, torsion, and synchrony in the left ventricle (LV). Methods Ten 12-week-old C57BL/6 J mice were randomized to a high-fat or low-fat diet. After 5 months on the diet, mice were imaged with a 7 T ClinScan using a cine DENSE protocol. Three short-axis and two long-axis slices were acquired for quantification of strains, torsion and synchrony in the left ventricle. Results Left ventricular mass was increased by 15% (p?=?0.032) with no change in volumes or ejection fraction. Subepicardial strain was lower in the obese mice with a 40% reduction in circumferential strain (p?=?0.008) a 53% reduction in radial strain (p?=?0.032) and a trend towards a 19% reduction in longitudinal strain (p?=?0.056). By contrast, subendocardial strain was modestly reduced in the obese mice in the circumferential direction by 12% (p?=?0.028), and no different in the radial (p?=?0.690) or longitudinal (p?=?0.602) directions. Peak torsion was reduced by 34% (p?=?0.028). Synchrony of contraction was also reduced (p?=?0.032) with a time delay in the septal-to-lateral direction. Conclusions Diet-induced obesity reduces left ventricular strains and torsion in mice. Reductions in cardiac strain are mostly limited to the subepicardium, with relative preservation of function in the subendocardium. Diet-induced obesity also leads to reduced synchrony of contraction and hypertrophy in mouse models. PMID:24380567

  5. Effect of Ghrelin on Mortality and Cardiovascular Outcomes in Experimental Rat and Mice Models of Heart Failure: A Systematic Review and Meta-Analysis

    PubMed Central

    Khatib, Mahalaqua Nazli; Shankar, Anuraj; Kirubakaran, Richard; Agho, Kingsley; Simkhada, Padam; Gaidhane, Shilpa; Saxena, Deepak; B, Unnikrishnan; Gode, Dilip; Gaidhane, Abhay; Zahiruddin, Syed Quazi

    2015-01-01

    Background Heart failure (HF) continues to be a challenging condition in terms of prevention and management of the disease. Studies have demonstrated various cardio-protective effects of Ghrelin. The aim of the study is to determine the effect of Ghrelin on mortality and cardiac function in experimental rats/mice models of HF. Methods Data sources: PUBMED, Scopus. We searched the Digital Dissertations and conference proceedings on Web of Science. Search methods: We systematically searched for all controlled trials (upto November 2014) which assessed the effects of Ghrelin (irrespective of dose, form, frequency, duration and route of administration) on mortality and cardiac function in rats/ mice models of HF. Ghrelin administration irrespective of dose, form, frequency, duration and route of administration. Data collection and analysis: Two authors independently assessed each abstract for eligibility and extracted data on characteristics of the experimental model used, intervention and outcome measures. We assessed the methodological quality by SYRCLE’s risk of bias tool for all studies and the quality of evidence by GRADEpro. We performed meta-analysis using RevMan 5.3. Results A total of 325 animals (rats and mice) were analyzed across seven studies. The meta-analysis revealed that the mortality in Ghrelin group was 31.1% and in control group was 40% (RR 0.83, 95% CI 0.46 to 1.47) i.e Ghrelin group had 68 fewer deaths per 1000 (from 216 fewer to 188 more) as compared to the control group. The meta-analysis reveals that the heart rate in rats/mice on Ghrelin was higher (MD 13.11, 95% CI 1.14 to 25.08, P=0.66) while the mean arterial blood pressure (MD -1.38, 95% CI -5.16 to 2.41, P=0.48) and left ventricular end diastolic pressure (MD -2.45, 95% CI -4.46 to -0.43, P=0.02) were lower as compared to the those on placebo. There were insignificant changes in cardiac output (SMD 0.28, 95% CI -0.24 to 0.80, P=0.29) and left ventricular end systolic pressure (MD 1.48, 95% CI -3.86 to 6.82, P=0.59). Conclusions The existing data provides evidence to suggest that Ghrelin may lower the risk of mortality and improve cardiovascular outcomes. However; the quality of evidence as assessed by GRADEpro is low to very low. Clinical judgments to administer Ghrelin to patients with HF must be made on better designed animal studies. PMID:26016489

  6. Cardiovascular determinants of life span

    Microsoft Academic Search

    Yi Shi; Giovanni G. Camici; Thomas F. Lüscher

    2010-01-01

    The prevalence of cardiovascular diseases rises with aging and is one of the main causes of mortality in western countries.\\u000a In view of the progressively aging population, there is an urge for a better understanding of age-associated cardiovascular\\u000a diseases and its underlying molecular mechanisms. The risk factors for cardiovascular diseases include unhealthy diet, diabetes,\\u000a obesity, smoking, alcohol consumption, physical inactivity,

  7. Sleep Apnea and Cardiovascular Disease

    Microsoft Academic Search

    Alexander G. Logan; T. Douglas Bradley

    2010-01-01

    Cardiovascular disease is still the leading cause of death in North America. To improve outcomes, it will likely be necessary\\u000a to identify new potentially treatable conditions. Sleep apnea affects approximately 50% of patients with cardiovascular disease\\u000a and is associated with increased cardiovascular risk. Continuous positive airway pressure is currently the treatment of choice\\u000a and has many short-term favorable effects. The

  8. System model of an image stabilization system

    NASA Astrophysics Data System (ADS)

    Carmona, Manuel; Gómez, José María.; Roma, David; Casas, Albert; López, Manel; Bosch, José; Herms, Atilà; Sabater, Josep; Volkmer, Reiner; Heidecke, Frank; Maue, Thorsten; Nakai, Eiji; Schmidt, Wolfgang

    2014-08-01

    The Polarimetric and Helioseismic Imager (PHI) instrument is part of the remote instruments for the ESA Solar Orbiter (SO), which is scheduled to launch in 2017. PHI captures polarimetric images from the Sun to better understand our nearest star, the Sun. A set of images is acquired with different polarizations, and afterwards is processed to extract the Stokes parameters. As Stokes parameters require the subtraction of the image values, in order to get the desired quality it is necessary to have good contrast in the image and very small displacements between them. As a result an Image Stabilization System (ISS) is required. This paper is focused in the behavior and the main characteristics of this system. This ISS is composed of a camera, a tip-tilt mirror and a control system. The camera is based on a STAR1000 sensor that includes a 10 bits resolution high-speed Analog-to-Digital Converter (ADC). The control system includes a Correlation Tracking (CT) algorithm that determines the necessary corrections. The tip-tilt mirror is moved based on this corrections to minimize the effects of the spacecraft (S/C) drift and jitter with respect to the Sun. Due to its stringent requirements, a system model has been developed in order to verify that the required parameters can be satisfied. The results show that the ISS is feasible, although the margins are very small.

  9. Mathematical models of endocrine systems

    Microsoft Academic Search

    Lewis Danziger; George L. Elmergreen

    1957-01-01

    There is proposed a generalized mathematical model of endocrine systems, consisting of a set of differential equations which\\u000a describe a chain of chemical reactions. The product of each reaction stimulates or inhibits some other reaction in the chain\\u000a except possibly the last, which may or may not influence the system. At least one reaction must be independent and able to

  10. The cardiovascular response to the AGS

    NASA Technical Reports Server (NTRS)

    Cardus, David; Mctaggart, Wesley G.

    1993-01-01

    This paper reports the preliminary results of experiments on human subjects conducted to study the cardiovascular response to various g-levels and exposure times using an artificial gravity simulator (AGS). The AGS is a short arm centrifuge consisting of a turntable, a traction system, a platform and four beds. Data collection hardware is part of the communication system. The AGS provides a steep acceleration gradient in subjects in the supine position.

  11. [Sleep rhythm and cardiovascular diseases].

    PubMed

    Maemura, Koji

    2012-07-01

    Sleep disturbance is a common problem in general adult population. Recent evidence suggests the link between the occurrence of cardiovascular events and several sleep disturbances including sleep apnea syndrome, insomnia and periodic limb movements during sleep. Sleep duration may affect the cardiovascular outcome. Shift work also may increase the risk of ischemic heart disease. Normalization of sleep rhythm has a potential to be a therapeutic target of ischemic heart diseases, although further study is required to evaluate the preventive effect on cardiovascular events. Here we describe the current understandings regarding the roles of sleep disorders during the pathogenesis of cardiovascular events. PMID:22844804

  12. Oxidative Stress in Cardiovascular Disease

    PubMed Central

    Csányi, Gábor; Miller, Francis J.

    2014-01-01

    In the special issue “Oxidative Stress in Cardiovascular Disease” authors were invited to submit papers that investigate key questions in the field of cardiovascular free radical biology. The original research articles included in this issue provide important information regarding novel aspects of reactive oxygen species (ROS)-mediated signaling, which have important implications in physiological and pathophysiological cardiovascular processes. The issue also included a number of review articles that highlight areas of intense research in the fields of free radical biology and cardiovascular medicine. PMID:24722571

  13. Cardiovascular Adjustments to Gravitational Stress

    NASA Technical Reports Server (NTRS)

    Blomqvist, C. Gunnar; Stone, H. Lowell

    1991-01-01

    The effects of gravity on the cardiovascular system must be taken into account whenever a hemodynamic assessment is made. All intravascular pressure have a gravity-dependent hydrostatic component. The interaction between the gravitational field, the position of the body, and the functional characteristics of the blood vessels determines the distribution of intravascular volume. In turn this distribution largely determines cardiac pump function. Multiple control mechanisms are activated to preserve optimal tissue perfusion when the magnitude of the gravitational field or its direction relative to the body changes. Humans are particularly sensitive to such changes because of the combination of their normally erect posture and the large body mass and blood volume below the level of the heart. Current aerospace technology also exposes human subjects to extreme variations in the gravitational forces that range from zero during space travel to as much an nine-times normal during operation of high-performance military aircraft. This chapter therefore emphasizes human physiology.

  14. Video distribution system cost model

    NASA Technical Reports Server (NTRS)

    Gershkoff, I.; Haspert, J. K.; Morgenstern, B.

    1980-01-01

    A cost model that can be used to systematically identify the costs of procuring and operating satellite linked communications systems is described. The user defines a network configuration by specifying the location of each participating site, the interconnection requirements, and the transmission paths available for the uplink (studio to satellite), downlink (satellite to audience), and voice talkback (between audience and studio) segments of the network. The model uses this information to calculate the least expensive signal distribution path for each participating site. Cost estimates are broken downy by capital, installation, lease, operations and maintenance. The design of the model permits flexibility in specifying network and cost structure.

  15. CRP in Cardiovascular Disease

    Microsoft Academic Search

    Mahir Karakas; Wolfgang Koenig

    2009-01-01

    \\u000a Abstract\\u000a   In primary prevention, traditional risk factors are a useful\\u000a first step in determining who is at cardiovascular\\u000a risk, however, it has been noted that a considerable\\u000a number of those at risk cannot be identified on the basis\\u000a of traditional risk factors alone. Among blood biomarkers,\\u000a C-reactive protein (CRP), measured by\\u000a high-sensitivity assays (hsCRP), has received widespread\\u000a interest and a

  16. Nonlinear dynamics of cardiovascular ageing

    PubMed Central

    Shiogai, Y.; Stefanovska, A.; McClintock, P.V.E.

    2010-01-01

    The application of methods drawn from nonlinear and stochastic dynamics to the analysis of cardiovascular time series is reviewed, with particular reference to the identification of changes associated with ageing. The natural variability of the heart rate (HRV) is considered in detail, including the respiratory sinus arrhythmia (RSA) corresponding to modulation of the instantaneous cardiac frequency by the rhythm of respiration. HRV has been intensively studied using traditional spectral analyses, e.g. by Fourier transform or autoregressive methods, and, because of its complexity, has been used as a paradigm for testing several proposed new methods of complexity analysis. These methods are reviewed. The application of time–frequency methods to HRV is considered, including in particular the wavelet transform which can resolve the time-dependent spectral content of HRV. Attention is focused on the cardio-respiratory interaction by introduction of the respiratory frequency variability signal (RFV), which can be acquired simultaneously with HRV by use of a respiratory effort transducer. Current methods for the analysis of interacting oscillators are reviewed and applied to cardio-respiratory data, including those for the quantification of synchronization and direction of coupling. These reveal the effect of ageing on the cardio-respiratory interaction through changes in the mutual modulation of the instantaneous cardiac and respiratory frequencies. Analyses of blood flow signals recorded with laser Doppler flowmetry are reviewed and related to the current understanding of how endothelial-dependent oscillations evolve with age: the inner lining of the vessels (the endothelium) is shown to be of crucial importance to the emerging picture. It is concluded that analyses of the complex and nonlinear dynamics of the cardiovascular system can illuminate the mechanisms of blood circulation, and that the heart, the lungs and the vascular system function as a single entity in dynamical terms. Clear evidence is found for dynamical ageing. PMID:20396667

  17. Nonlinear dynamics of cardiovascular ageing

    NASA Astrophysics Data System (ADS)

    Shiogai, Y.; Stefanovska, A.; McClintock, P. V. E.

    2010-03-01

    The application of methods drawn from nonlinear and stochastic dynamics to the analysis of cardiovascular time series is reviewed, with particular reference to the identification of changes associated with ageing. The natural variability of the heart rate (HRV) is considered in detail, including the respiratory sinus arrhythmia (RSA) corresponding to modulation of the instantaneous cardiac frequency by the rhythm of respiration. HRV has been intensively studied using traditional spectral analyses, e.g. by Fourier transform or autoregressive methods, and, because of its complexity, has been used as a paradigm for testing several proposed new methods of complexity analysis. These methods are reviewed. The application of time-frequency methods to HRV is considered, including in particular the wavelet transform which can resolve the time-dependent spectral content of HRV. Attention is focused on the cardio-respiratory interaction by introduction of the respiratory frequency variability signal (RFV), which can be acquired simultaneously with HRV by use of a respiratory effort transducer. Current methods for the analysis of interacting oscillators are reviewed and applied to cardio-respiratory data, including those for the quantification of synchronization and direction of coupling. These reveal the effect of ageing on the cardio-respiratory interaction through changes in the mutual modulation of the instantaneous cardiac and respiratory frequencies. Analyses of blood flow signals recorded with laser Doppler flowmetry are reviewed and related to the current understanding of how endothelial-dependent oscillations evolve with age: the inner lining of the vessels (the endothelium) is shown to be of crucial importance to the emerging picture. It is concluded that analyses of the complex and nonlinear dynamics of the cardiovascular system can illuminate the mechanisms of blood circulation, and that the heart, the lungs and the vascular system function as a single entity in dynamical terms. Clear evidence is found for dynamical ageing.

  18. Proceedings of the ECCOMAS Thematic International Conference on Simulation and Modeling of Biological Flows (SIMBIO 2011)

    E-print Network

    cardiovascular system [1]. However, the complexity of the circulatory system makes modeling and simulation on the main component of the circulatory system: the heart. More specifically, we are interested

  19. Molecular determinants for a cardiovascular collapse in anthrax.

    PubMed

    Brojatsch, Jurgen; Casadevall, Arturo; Goldman, David L

    2014-01-01

    Bacillus anthracis releases two bipartite proteins, lethal toxin and edema factor, that contribute significantly to the progression of anthrax-associated shock. As blocking the anthrax toxins prevents disease, the toxins are considered the main virulence factors of the bacterium. The anthrax bacterium and the anthrax toxins trigger multi-organ failure associated with enhanced vascular permeability, hemorrhage and cardiac dysfunction in animal challenge models. A recent study using mice that either lacked the anthrax toxin receptor in specific cells and corresponding mice expressing the receptor in specific cell types demonstrated that cardiovascular cells are critical for disease mediated by anthrax lethal toxin. These studies are consistent with involvement of the cardiovascular system, and with an increase of cardiac failure markers observed in human anthrax and in animal models using B. anthracis and anthrax toxins. This review discusses the current state of knowledge regarding the pathophysiology of anthrax and tries to provide a mechanistic model and molecular determinants for the circulatory shock in anthrax. PMID:24389148

  20. Molecular determinants for a cardiovascular collapse in anthrax

    PubMed Central

    Brojatsch, Jurgen; Casadevall, Arturo; Goldman, David L.

    2015-01-01

    Bacillus anthracis releases two bipartite proteins, lethal toxin and edema factor, that contribute significantly to the progression of anthrax-associated shock. As blocking the anthrax toxins prevents disease, the toxins are considered the main virulence factors of the bacterium. The anthrax bacterium and the anthrax toxins trigger multiorgan failure associated with enhanced vascular permeability, hemorrhage and cardiac dysfunction in animal challenge models. A recent study using mice that either lacked the anthrax toxin receptor in specific cells and corresponding mice expressing the receptor in specific cell types demonstrated that cardiovascular cells are critical for disease mediated by anthrax lethal toxin. These studies are consistent with involvement of the cardiovascular system, and with an increase of cardiac failure markers observed in human anthrax and in animal models using B. anthracis and anthrax toxins. This review discusses the current state of knowledge regarding the pathophysiology of anthrax and tries to provide a mechanistic model and molecular determinants for the circulatory shock in anthrax. PMID:24389148

  1. Models for multimegawatt space power systems

    SciTech Connect

    Edenburn, M.W.

    1990-06-01

    This report describes models for multimegawatt, space power systems which Sandia's Advanced Power Systems Division has constructed to help evaluate space power systems for SDI's Space Power Office. Five system models and models for associated components are presented for both open (power system waste products are exhausted into space) and closed (no waste products) systems: open, burst mode, hydrogen cooled nuclear reactor -- turboalternator system; open, hydrogen-oxygen combustion turboalternator system; closed, nuclear reactor powered Brayton cycle system; closed, liquid metal Rankine cycle system; and closed, in-core, reactor therminonic system. The models estimate performance and mass for the components in each of these systems. 17 refs., 8 figs., 15 tabs.

  2. Heat waves, aging, and human cardiovascular health.

    PubMed

    Kenney, W Larry; Craighead, Daniel H; Alexander, Lacy M

    2014-10-01

    This brief review is based on a President's Lecture presented at the Annual Meeting of the American College of Sports Medicine in 2013. The purpose of this review was to assess the effects of climate change and consequent increases in environmental heat stress on the aging cardiovascular system. The earth's average global temperature is slowly but consistently increasing, and along with mean temperature changes come increases in heat wave frequency and severity. Extreme passive thermal stress resulting from prolonged elevations in ambient temperature and prolonged physical activity in hot environments creates a high demand on the left ventricle to pump blood to the skin to dissipate heat. Even healthy aging is accompanied by altered cardiovascular function, which limits the extent to which older individuals can maintain stroke volume, increase cardiac output, and increase skin blood flow when exposed to environmental extremes. In the elderly, the increased cardiovascular demand during heat waves is often fatal because of increased strain on an already compromised left ventricle. Not surprisingly, excess deaths during heat waves 1) occur predominantly in older individuals and 2) are overwhelmingly cardiovascular in origin. Increasing frequency and severity of heat waves coupled with a rapidly growing at-risk population dramatically increase the extent of future untoward health outcomes. PMID:24598696

  3. Focus On: The Cardiovascular System

    PubMed Central

    Mochly-Rosen, Daria; Zakhari, Samir

    2010-01-01

    Although heavy alcohol consumption has deleterious effects on heart health, moderate drinking is thought to have cardioprotective effects, reducing the risk of coronary artery disease and improving prognosis after a myocardial infarction. It still is unclear, however, if this effect can be achieved with all types of alcoholic beverages and results from the alcohol itself, from other compounds found in alcoholic beverages, or both. For example, the polyphenolic compound resveratrol, which is found particularly in red wine, can reduce the risk of atherosclerosis; however, it is not clear if the resveratrol levels present in wine are sufficient to achieve this result. Alcohol itself contributes to cardioprotection through several mechanisms. For example, it can improve the cholesterol profile, increasing the levels of “good” cholesterol and reducing the levels of “bad” cholesterol. Alcohol also may contribute to blood clot dissolution and may induce a phenomenon called pre-conditioning, whereby exposure to moderate alcohol levels (like short bouts of blood supply disruption [i.e., ischemia]), and result in reduced damage to the heart tissue after subsequent prolonged ischemia. Finally, the enzyme aldehyde dehydrogenase (ALDH) 2, which is involved in alcohol metabolism, also may contribute to alcohol-related cardioprotection by metabolizing other harmful aldehydes that could damage the heart muscle. PMID:23579938

  4. Protein O-GlcNAcylation and cardiovascular (patho)physiology.

    PubMed

    Marsh, Susan A; Collins, Helen E; Chatham, John C

    2014-12-12

    Our understanding of the role of protein O-GlcNAcylation in the regulation of the cardiovascular system has increased rapidly in recent years. Studies have linked increased O-GlcNAc levels to glucose toxicity and diabetic complications; conversely, acute activation of O-GlcNAcylation has been shown to be cardioprotective. However, it is also increasingly evident that O-GlcNAc turnover plays a central role in the delicate regulation of the cardiovascular system. Therefore, the goals of this minireview are to summarize our current understanding of how changes in O-GlcNAcylation influence cardiovascular pathophysiology and to highlight the evidence that O-GlcNAc cycling is critical for normal function of the cardiovascular system. PMID:25336635

  5. Abdominal Problems in Children with Congenital Cardiovascular Abnormalities

    PubMed Central

    Güney, Lütfi Hakan; Araz, Co?kun; Beyazp?nar, Deniz Sarp; Arda, ?rfan Serdar; Arslan, Esra Elif; Hiçsönmez, Akgün

    2015-01-01

    Background: Congenital cardiovascular abnormality is an important cause of morbidity and mortality in childhood. Both the type of congenital cardiovascular abnormality and cardiopulmonary bypass are responsible for gastrointestinal system problems. Aims: Intra-abdominal problems, such as paralytic ileus, necrotizing enterocolitis, and intestinal perforation, are common in patients who have been operated or who are being followed for congenital cardiovascular abnormalities. Besides the primary congenital cardiovascular abnormalities, ischemia secondary to cardiac catheterization or surgery contributes to the incidence of these problems. Study Design: Cross-sectional study. Methods: In this study, we aimed to screen the intra-abdominal problems seen in patients with congenital cardiovascular abnormalities who had undergone surgical or angiographical intervention(s). Patients with congenital cardiovascular abnormalities who had been treated medically or surgically between 2000 and 2014 were analyzed retrospectively in terms of intra-abdominal problems. The patients’ demographic data, type of congenital cardiovascular abnormalities, the intervention applied (surgical, angiographic), the incidence of intra-abdominal problem(s), the interventions applied for the intra-abdominal problems, and the results were evaluated. Results: Fourteen (Group I) of the 76 patients with congenital cardiovascular abnormalities diagnosis were operated due to intra-abdominal problems, and 62 (Group II) were followed-up clinically for intra-abdominal problems. In Group I (10 boys and 4 girls), 11 patients were aged between 0 and 12 months, and three patients were older than 12 months. Group II included 52 patients aged between 0 and 12 months and 10 patients older than 12 months. Cardiovascular surgical interventions had been applied to six patients in Group I and 40 patients in Group II. The most frequent intra-abdominal problems were necrotizing enterocolitis and intestinal perforation in Group I, and paralytic ileus in Group II. Seven of the Group I patients and 22 of the Group II patients died. The patients who died in both groups had more than three congenital cardiovascular abnormalities in the same patient, and 80% of these patients had been operated for congenital cardiovascular abnormalities. Conclusion: The gastrointestinal system is involved in important complications experienced by patients with congenital cardiovascular abnormalities. The mortality rate was higher in operated patients due to gastrointestinal complications. Gastrointestinal complications are more frequent in patients with cyanotic anomalies. The presence of more than one congenital cardiovascular abnormality in a patient increased the mortality rate. PMID:26185717

  6. Modeling distributed hybrid systems in Ptolemy II

    Microsoft Academic Search

    Jie Liu; Xiaojun Liu; Edward A. Lee

    2001-01-01

    We present Ptolemy II as a modeling and simulation environment for distributed hybrid systems. In Ptolemy II, a distributed hybrid system is specified as a hierarchy of models: an event-based top level and distributed islands of hybrid systems. Each hybrid system is in turn a hierarchy of continuous-time models and finite state machines. A variety of models of computation was

  7. Cardiovascular medication: improving adherence

    PubMed Central

    2011-01-01

    Introduction Adherence to medication is generally defined as the extent to which people take medications as prescribed by their healthcare providers. It can be assessed in many ways (e.g., by self-reporting, pill counting, direct observation, electronic monitoring, or by pharmacy records). This review reports effects of intervention on adherence to cardiovascular medications however adherence has been measured. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of interventions to improve adherence to long-term medication for cardiovascular disease in adults? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 39 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: patient health education, prescriber education, prompting mechanisms, reminder packaging (calendar [blister] packs, multi-dose pill boxes), and simplified dosing. PMID:21481286

  8. Cardiovascular medication: improving adherence

    PubMed Central

    2009-01-01

    Introduction Adherence to medication is generally defined as the extent to which people take medications as prescribed by their healthcare providers. It can be assessed in many ways (e.g., by self-reporting, pill counting, direct observation, electronic monitoring, or by pharmacy records). This review reports effects of intervention on adherence to cardiovascular medications however adherence has been measured. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical question: What are the effects of interventions to improve adherence to long-term medication for cardiovascular disease in adults? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 39 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: patient health education; prescriber education; prompting mechanisms; reminder packaging (calendar [blister] packs; multi-dose pill boxes); and simplified dosing.

  9. Cardiovascular effects of sub-daily levels of ambient fine particles: a systematic review

    PubMed Central

    2010-01-01

    Background While the effects of daily fine particulate exposure (PM) have been well reviewed, the epidemiological and physiological evidence of cardiovascular effects associated to sub-daily exposures has not. We performed a theoretical model-driven systematic non-meta-analytical literature review to document the association between PM sub-daily exposures (?6 hours) and arrhythmia, ischemia and myocardial infarction (MI) as well as the likely mechanisms by which sub-daily PM exposures might induce these acute cardiovascular effects. This review was motivated by the assessment of the risk of exposure to elevated sub-daily levels of PM during fireworks displays. Methods Medline and Elsevier's EMBase were consulted for the years 1996-2008. Search keywords covered potential cardiovascular effects, the pollutant of interest and the short duration of the exposure. Only epidemiological and experimental studies of adult humans (age > 18 yrs) published in English were reviewed. Information on design, population and PM exposure characteristics, and presence of an association with selected cardiovascular effects or physiological assessments was extracted from retrieved articles. Results Of 231 articles identified, 49 were reviewed. Of these, 17 addressed the relationship between sub-daily exposures to PM and cardiovascular effects: five assessed ST-segment depression indicating ischemia, eight assessed arrhythmia or fibrillation and five considered MI. Epidemiologic studies suggest that exposure to sub-daily levels of PM is associated with MI and ischemic events in the elderly. Epidemiological studies of sub-daily exposures suggest a plausible biological mechanism involving the autonomic nervous system while experimental studies suggest that vasomotor dysfunction may also relate to the occurrence of MI and ischemic events. Conclusions Future studies should clarify associations between cardiovascular effects of sub-daily PM exposure with PM size fraction and concurrent gaseous pollutant exposures. Experimental studies appear more promising for elucidating the physiological mechanisms, time courses and causes than epidemiological studies which employ central pollution monitors for measuring effects and for assessing their time course. Although further studies are needed to strengthen the evidence, given that exposure to sub-daily high levels of PM (for a few hours) is frequent and given the suggestive evidence that sub-daily PM exposures are associated with the occurrence of cardiovascular effects, we recommend that persons with cardiovascular diseases avoid such situations. PMID:20550697

  10. Association of myeloperoxidase with total and cardiovascular mortality in individuals undergoing coronary angiography—The LURIC study

    PubMed Central

    Scharnagl, Hubert; Kleber, Marcus E.; Genser, Bernd; Kickmaier, Sandra; Renner, Wilfried; Weihrauch, Gisela; Grammer, Tanja; Rossmann, Christine; Winkelmann, Bernhard R.; Boehm, Bernhard O.; Sattler, Wolfgang; März, Winfried; Malle, Ernst

    2014-01-01

    Background The phagocytic enzyme myeloperoxidase (MPO) acts as a front-line defender against microorganisms. However, increased MPO levels have been found to be associated with complex and calcified atherosclerotic lesions and incident cardiovascular disease. Therefore, this study aimed to investigate a predictive role of MPO, a biomarker of inflammation and oxidative stress, for total and cardiovascular mortality in patients referred to coronary angiography. Methods and results MPO plasma concentrations along with eight MPO polymorphisms were determined in 3036 participants of the Ludwigshafen Risk and Cardiovascular Health study (median follow-up 7.75 years). MPO concentrations were positively associated with age, diabetes, smoking, markers of systemic inflammation (interleukin-6, fibrinogen, C-reactive protein, serum amyloid A) and vascular damage (vascular cellular adhesion molecule-1 and intercellular adhesion molecule-1) but negatively associated with HDL-cholesterol and apolipoprotein A-I. After adjustment for cardiovascular risk factors MPO concentrations in the highest versus the lowest quartile were associated with a 1.34-fold risk (95% CI: 1.09–1.67) for total mortality. In the adjusted model the hazard ratio for cardiovascular mortality in the highest MPO quartile was 1.42 (95% CI: 1.07–1.88). Five MPO polymorphisms were positively associated with MPO concentrations but not with mortality. Using Mendelian randomization, we did not obtain evidence for a causal association of MPO with either total or cardiovascular mortality. Conclusions MPO concentrations but not genetic variants at the MPO locus are independently associated with risk for total and cardiovascular mortality in coronary artery disease patients. PMID:24746542

  11. Managed care challenges and opportunities for cardiovascular advanced practice nurses.

    PubMed

    Urban, N

    1997-02-01

    The aggressive changes in the health-care system are mandating revolutionary new approaches in patient-care delivery. Cardiovascular care, in particular, is under scrutiny due to its high cost and wide variation in outcome. The need to comprehensively coordinate cardiac surgical care and aggressively manage complex cases has resulted in growing interest in using cardiovascular advanced practice nurses (APNs) to ensure high-quality, yet cost-effective patient care. The unique skills of the cardiovascular APN as practitioner, consultant, educator, researcher, and change agent ensure optimal outcomes for patients and their families as well the staff, physicians, and the hospital's bottom line. PMID:9086921

  12. Quantitative Predictive Models for Systemic Toxicity (SOT)

    EPA Science Inventory

    Models to identify systemic and specific target organ toxicity were developed to help transition the field of toxicology towards computational models. By leveraging multiple data sources to incorporate read-across and machine learning approaches, a quantitative model of systemic ...

  13. The emergent neural modeling system.

    PubMed

    Aisa, Brad; Mingus, Brian; O'Reilly, Randy

    2008-10-01

    Emergent (http://grey.colorado.edu/emergent) is a powerful tool for the simulation of biologically plausible, complex neural systems that was released in August 2007. Inheriting decades of research and experience in network algorithms and modeling principles from its predecessors, PDP++ and PDP, Emergent has been redesigned as an efficient workspace for academic research and an engaging, easy-to-navigate environment for students. The system provides a modern and intuitive interface for programming and visualization centered around hierarchical, tree-based navigation and drag-and-drop reorganization. Emergent contains familiar, high-level simulation constructs such as Layers and Projections, a wide variety of algorithms, general-purpose data handling and analysis facilities and an integrated virtual environment for developing closed-loop cognitive agents. For students, the traditional role of a textbook has been enhanced by wikis embedded in every project that serve to explain, document, and help newcomers engage the interface and step through models using familiar hyperlinks. For advanced users, the software is easily extensible in all respects via runtime plugins, has a powerful shell with an integrated debugger, and a scripting language that is fully symmetric with the interface. Emergent strikes a balance between detailed, computationally expensive spiking neuron models and abstract, Bayesian or symbolic systems. This middle level of detail allows for the rapid development and successful execution of complex cognitive models while maintaining biological plausibility. PMID:18684591

  14. Cardiovascular Malformations Among Preterm Infants

    Microsoft Academic Search

    Kirsty Tanner; Nilofer Sabrine; Christopher Wren

    2010-01-01

    Objective. Preterm birth and cardiovas- cular malformations are the 2 most common causes of neonatal and infant death, but there are no published population-based reports on the relationship between them. We undertook this study to determine the preva- lence and spectrum of cardiovascular malformations in a preterm population, the prevalence of prematurity among infants with cardiovascular malformations, and the influence

  15. Cardiovascular risk factors in centenarians

    Microsoft Academic Search

    Antonio Galioto; Ligia J. Dominguez; Antonella Pineo; Anna Ferlisi; Ernesto Putignano; Mario Belvedere; Giuseppe Costanza; Mario Barbagallo

    Several studies have shown that centenarians have better cardiovascular risk profiles compared to younger old people. Some reports have revealed that cardiovascular diseases (i.e. hypertension, diabetes, angina and\\/or myocardial infarction) are less common in cente- narians respect to 70 and 80 years old persons. In order to explain this evidence, there is a growing number of hypothesis that consider a

  16. Cardiovascular involvement in relapsing polychondritis

    Microsoft Academic Search

    Attilio Del Rosso; Nunzia Rosa Petix; Mauro Pratesi; Alessandro Bini

    1997-01-01

    Relapsing polychondritis is an inflammatory disease that characteristically involves cartilagenous tissues. Cardiovascular involvement is a fairly common complication and the second most frequent cause of mortality in this disease. The case of a man with a progressive cardiac involvement, aortic incompetence, mitral regurgitation, and finally complete atrioventricular block offered the opportunity of reviewing the cardiovascular complications in relapsing polychondritis. The

  17. The Cardiovascular Curriculum Education Project

    ERIC Educational Resources Information Center

    White, R. C.; And Others

    1977-01-01

    The National Heart and Blood Vessel Research and Demonstration Center has developed a program called the Cardiovascular Curriculum Education Project, designed for secondary school students, which consists of self-instructional education units on cardiovascular disease and associated risk factors. Describes its three major components and method of…

  18. Oxidant-mediated activation of mitogen-activated protein kinases and nuclear transcription factors in the cardiovascular system: a brief overview.

    PubMed

    Chakraborti, S; Chakraborti, T

    1998-11-01

    In response to oxidant stress, the cardiovascular system is known to express a number of genes, which could occur owing to the participation of mitogen-activated protein kinases such as MAPKs, ERK and JNK (SAPK) followed by stimulation of at least two well-defined transcription factors NF-KB and AP-1 (c-Fos and c-Jun). Oxidants activate cytosolic and membrane-bound PLA2 activities with the subsequent production of AA metabolites such as HETEs, which subsequently stimulate ERK and JNK (SAPK) activities leading to the activation of transcriptional factors and the ultimate stimulation of the transcription of several mitogen-stress-responsive genes. LacCer, a ceramide analogue present in atherosclerotic plaques, has been found to induce proliferation of aortic smooth muscle cells. LacCer is involved in Ras-GTP loading, activation of kinase cascades (MEK, Raf, p44 MAPK) and c-fos expression. TNF-alpha, on the other hand, induces c-fos, c-myc and c-jun expression. Recent investigations link ceramide and its analogues to the extracellular signal-regulated kinase (ERK) cascade, stress-activated protein kinase-c-Jun kinase (SAPK/JNK) cascade and apoptotic responses. These critical steps in the signalling pathways are sensitive to intracellular thiol-redox and protease(s)-antiprotease(s) status, both of which can be modified by oxidants. Because mobilisation of intracellular Ca2+ caused by a variety of signals also plays a role in the activation of the signalling pathways, an important aspect of future work will be to ascertain the roles of oxidants and Ca2+ individually and in combination in the activation of the signalling pathways. The following two important questions also deserve future attention: (1) How does NF-kB shield cells from apoptotic death? and (2) By what mechanisms does the activated NF-kB cause cellular transformation? Furthermore, the role of AP-1 acting as transcriptional activator seems clear, but the target genes remain to be defined. PMID:9884018

  19. Non-invasive assessment of cardiac function and pulmonary vascular resistance in an canine model of acute thromboembolic pulmonary hypertension using 4D flow cardiovascular magnetic resonance

    PubMed Central

    2014-01-01

    Background The purpose of this study was to quantify right (RV) and left (LV) ventricular function, pulmonary artery flow (QP), tricuspid valve regurgitation velocity (TRV), and aorta flow (QS) from a single 4D flow cardiovascular magnetic resonance (CMR) (time-resolved three-directionally motion encoded CMR) sequence in a canine model of acute thromboembolic pulmonary hypertension (PH). Methods Acute PH was induced in six female beagles by microbead injection into the right atrium. Pulmonary arterial (PAP) and pulmonary capillary wedge (PCWP) pressures and cardiac output (CO) were measured by right heart catheterization (RHC) at baseline and following induction of acute PH. Pulmonary vascular resistance (PVRRHC) was calculated from RHC values of PAP, PCWP and CO (PVRRHC?=?(PAP-PCWP)/CO). Cardiac magnetic resonance (CMR) was performed on a 3 T scanner at baseline and following induction of acute PH. RV and LV end-diastolic (EDV) and end-systolic (ESV) volumes were determined from both CINE balanced steady-state free precession (bSSFP) and 4D flow CMR magnitude images. QP, TRV, and QS were determined from manually placed cutplanes in the 4D flow CMR flow-sensitive images in the main (MPA), right (RPA), and left (LPA) pulmonary arteries, the tricuspid valve (TRV), and aorta respectively. MPA, RPA, and LPA flow was also measured using two-dimensional flow-sensitive (2D flow) CMR. Results Biases between 4D flow CMR and bSSFP were 0.8 mL and 1.6 mL for RV EDV and RV ESV, respectively, and 0.8 mL and 4 mL for LV EDV and LV ESV, respectively. Flow in the MPA, RPA, and LPA did not change after induction of acute PAH (p?=?0.42-0.81). MPA, RPA, and LPA flow determined with 4D flow CMR was significantly lower than with 2D flow (p?

  20. Results From the Periodontitis and Vascular Events (PAVE) Study: A Pilot Multicentered, Randomized, Controlled Trial to Study Effects of Periodontal Therapy in a Secondary Prevention Model of Cardiovascular Disease

    PubMed Central

    Offenbacher, Steven; Beck, James D.; Moss, Kevin; Mendoza, Luisito; Paquette, David W.; Barrow, David A.; Couper, David J.; Stewart, Dawn D.; Falkner, Karen L.; Graham, Susan P.; Grossi, Sara; Gunsolley, John C.; Madden, Theresa; Maupome, Gerardo; Trevisan, Maurizio; Van Dyke, Thomas E.; Genco, Robert J.

    2009-01-01

    Background In the Periodontitis and Vascular Events (PAVE) pilot study, periodontal therapy was provided as an intervention in a secondary cardiac event prevention model through five coordinated cardiac– dental centers. Methods Subjects were randomized to either community care or protocol provided scaling and root planing to evaluate effects on periodontal status and systemic levels of high-sensitivity C-reactive protein (hs-CRP). Results After 6 months, there was a significant reduction in mean probing depth and extent of 4- or 5-mm pockets. However, there were no significant differences in attachment levels, bleeding upon probing, or extent of subgingival calculus comparing subjects assigned to protocol therapy (n = 151) to those assigned to community care (n = 152). Using intent-to-treat analyses, there was no significant effect on serum hs-CRP levels at 6 months. However, 48% of the subjects randomized to community care received preventive or periodontal treatments. Secondary analyses demonstrated that consideration of any preventive or periodontal care (i.e., any treatment) compared to no treatment showed a significant reduction in the percentage of people with elevated hs-CRP (values >3 mg/l) at 6 months. However, obesity nullified the periodontal treatment effects on hs-CRP reduction. The adjusted odds ratio for hs-CRP levels >3 mg/l at 6 months for any treatment versus no treatment among non-obese individuals was 0.26 (95%confidence interval: 0.09 to 0.72), adjusting for smoking, marital status, and gender. Conclusion This pilot study demonstrated the critical role of considering obesity as well as rigorous preventive and periodontal care in trials designed to reduce cardiovascular risk. PMID:19186958