These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Computer model of cardiovascular control system responses to exercise  

NASA Technical Reports Server (NTRS)

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.

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

1973-01-01

2

A novel approach to modeling and diagnosing the cardiovascular system  

SciTech Connect

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.

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

3

A Computer Model of the Cardiovascular System for Effective Learning.  

ERIC Educational Resources Information Center

Presents a model of the cardiovascular system which solves a set of interacting, possibly nonlinear, differential equations. Figures present a schematic diagram of the model and printouts that simulate normal conditions, exercise, hemorrhage, reduced contractility. The nine interacting equations used to describe the system are described in the…

Rothe, Carl F.

1980-01-01

4

Silicon Baroreceptors: Modeling Cardiovascular  

E-print Network

Silicon Baroreceptors: Modeling Cardiovascular Pressure Transduction in Analog VLSI John Lazzaro pressure used in a neural control system in the cardiovascular system. The chip computes the representation as a first step to understanding the neural computation of cardiovascular control; we hope to apply

Lazzaro, John

5

A Computer Model of the Cardiovascular System for Effective Learning.  

ERIC Educational Resources Information Center

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)

Rothe, Carl F.

1979-01-01

6

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

E-print Network

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

Wu, Yi

7

A bond graph model of the cardiovascular system  

PubMed Central

The study of the autonomic nervous system (ANS) function has shown to provide useful indicators for risk stratification and early detection on a variety of cardiovascular pathologies. However, data gathered during different tests of the ANS are difficult to analyse, mainly due to the complex mechanisms involved in the autonomic regulation of the cardiovascular system (CVS). Although model-based analysis of ANS data has been already proposed as a way to cope with this complexity, only a few models coupling the main elements involved have been presented in the literature. In this paper, a new model of the CVS, representing the ventricles, the circulatory system and the regulation of the CVS activity by the ANS, is presented. The models of the vascular system and the ventricular activity have been developed using the Bond Graph formalism, as it proposes a unified representation for all energetic domains, facilitating the integration of mechanic and hydraulic phenomena. In order to take into account the electro-mechanical behaviour of both ventricles, an electrophysiologic model of the cardiac action potential, represented by a set of ordinary differential equations, has been integrated. The short-term ANS regulation of heart rate, cardiac contractility and peripheral vasoconstriction is represented by means of continuous transfer functions. These models, represented in different continuous formalisms, are coupled by using a multi-formalism simulation library. Results are presented for two different autonomic tests, namely the Tilt Test and the Valsalva Manoeuvre, by comparing real and simulated signals. PMID:16583271

Le Rolle, Virginie; Hernandez, Alfredo I.; Richard, Pierre-Yves; Buisson, Jean; Carrault, Guy

2005-01-01

8

Mathematical modelling of flow distribution in the human cardiovascular system  

NASA Technical Reports Server (NTRS)

The paper presents a detailed model of the entire human cardiovascular system which aims to study the changes in flow distribution caused by external stimuli, changes in internal parameters, or other factors. The arterial-venous network is represented by 325 interconnected elastic segments. The mathematical description of each segment is based on equations of hydrodynamics and those of stress/strain relationships in elastic materials. Appropriate input functions provide for the pumping of blood by the heart through the system. The analysis employs the finite-element technique which can accommodate any prescribed boundary conditions. Values of model parameters are from available data on physical and rheological properties of blood and blood vessels. As a representative example, simulation results on changes in flow distribution with changes in the elastic properties of blood vessels are discussed. They indicate that the errors in the calculated overall flow rates are not significant even in the extreme case of arteries and veins behaving as rigid tubes.

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

1992-01-01

9

Reintrepreting the cardiovascular system as a mechanical model  

NASA Astrophysics Data System (ADS)

The simulation of the different physiological systems is very useful as a pedagogical tool, allowing a better understanding of the mechanisms and the functions of the processes. The observation of the physiological phenomena through mechanical simulators represents a great asset. Furthermore, the development of these simulators allows reinterpreting physiological systems, with the advantage of using the same transducers and sensors that are commonly used in diagnostic and therapeutic cardiovascular procedures for the monitoring of system' parameters. The cardiovascular system is one of the most important systems of the human body and has been the target of several biomedical studies. The present work describes a mechanical simulation of the cardiovascular system, in particularly, the systemic circulation, which can be described in terms of its hemodynamic variables. From the mechanical process and parameters, physiological system's behavior was reproduced, as accurately as possible.

Lemos, Diogo; Machado, José; Minas, Graça; Soares, Filomena; Barros, Carla; Leăo, Celina Pinto

2013-10-01

10

A mathematic model of a cardiovascular system regulated by the baroreflex  

Microsoft Academic Search

A dynamic, nonlinear, lumped parameter model of the cardiovascular system coupled with a baroreflex model is presented. The cardiovascular system in the model consists of the left heart (ventricle) and systemic load and is represented by a fourth order nonlinear time-varying differential equation. The baroreflex is an important internal feedback mechanism in the body whose function is to regulate and

Shaohui Chen; A. Ferreira; M. A. Simaan; J. F. Antaki

2006-01-01

11

Mathematical modelling of flow distribution in the human cardiovascular system.  

PubMed

The paper presents a detailed model of the entire human cardiovascular system which aims to study the changes in flow distribution caused by external stimuli, changes in internal parameters, or other factors. The arterial-venous network is represented by 325 interconnected elastic segments. The mathematical description of each segment is based on equations of hydrodynamics and those of stress/strain relationships in elastic materials. Appropriate input functions provide for the pumping of blood by the heart through the system. The analysis employs the finite-element technique which can accommodate any prescribed boundary conditions. Values of model parameters are from available data on physical and rheological properties of blood and blood vessels. As a representative example, simulation results on changes in flow distribution with changes in the elastic properties of blood vessels are discussed. They indicate that the errors in the calculated overall flow rates are not significant even in the extreme case of arteries and veins behaving as rigid tubes. PMID:1453803

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

1992-05-01

12

Experimental Models of Renal Disease and the Cardiovascular System  

PubMed Central

Cardiovascular disease is a leading cause of death among patients with end stage renal failure. Animal models have played a crucial role in teasing apart the complex pathological processes involved. This review discusses the principles of using animal models, the history of their use in the study of renal hypertension, the controversies arising from experimental models of non-hypertensive uraemic cardiomyopathy and the lessons learned from these models, and highlights important areas of future research in this field, including de novo cardiomyopathy secondary to renal transplantation. PMID:21258578

Grossman, Rebecca C.

2010-01-01

13

Cardiovascular & Respiratory Modeling, Analysis & Control  

E-print Network

Cardiovascular & Respiratory Systems: Modeling, Analysis & Control J. J. Batzel, F. Kappel, D . . . . . . . . . . . . . . . . 36 1.7.3 Sensitivity analysis . . . . . . . . . . . . . . . . . . . 38 2 Respiratory Modeling 45 2.1 Respiratory Control Physiology . . . . . . . . . . . . . . . . . . 46 2.1.1 General features of respiration

Batzel, Jerry

14

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

E-print Network

, 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

Canic, Suncica

15

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

E-print Network

. 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

Boyer, Edmond

16

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

17

Mathematical modelling of the human cardiovascular system in the presence of stenosis  

NASA Technical Reports Server (NTRS)

This paper reports a theoretical study on the distribution of blood flow in the human cardiovascular system when one or more blood vessels are affected by stenosis. The analysis employs a mathematical model of the entire system based on the finite element method. The arterial-venous network is represented by a large number of interconnected segments in the model. Values for the model parameters are based upon the published data on the physiological and rheological properties of blood. Computational results show how blood flow through various parts of the cardiovascular system is affected by stenosis in different blood vessels. No significant changes in the flow parameters of the cardiovascular system were found to occur when the reduction in the lumen diameter of the stenosed vessels was less than 65%.

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

1993-01-01

18

Adaptive life simulator: A novel approach to modeling the cardiovascular system  

SciTech Connect

In this paper, an adaptive life simulator (ALS) is introduced. The ALS models a subset of the dynamics of the cardiovascular behavior of an individual by using a recurrent artificial neural network. These models are developed for use in applications that require simulations of cardiovascular systems, such as medical mannequins, and in medical diagnostic systems. 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 actual variables of an individual can subsequently be used for diagnosis. This approach also exploits sensor fusion applied to biomedical sensors. Sensor fusion optimizes the utilization of the sensors. The advantage of sensor fusion has been demonstrated in applications including control and diagnostics of mechanical and chemical processes.

Kangas, L.J.; Keller, P.E.; Hashem, S. [and others

1995-06-01

19

Medical Applications of Computer Modelling: Cardiovascular and Ocular Systems  

Microsoft Academic Search

ed T B Martonen WIT Press (2000) 290pp, price: Ł89.00, ISBN: 1 85312 613 6 The rapid growth in computer power in recent years has stimulated great interest in computational modelling of biological systems, and it is now an important growth area. This book aims to provide both reference material for researchers, and educational material for classwork. Although the title

Richard Clayton

2001-01-01

20

Computational Models of the Cardiovascular System and Its Response to Microgravity  

NASA Technical Reports Server (NTRS)

Computational models of the cardiovascular system are powerful adjuncts to ground-based and in-flight experiments. We will provide NSBRI with a model capable of simulating the short-term effects of gravity on cardiovascular function. The model from this project will: (1) provide a rational framework which quantitatively defines interactions among complex cardiovascular parameters and which supports the critical interpretation of experimental results and testing of hypotheses. (2) permit predictions of the impact of specific countermeasures in the context of various hypothetical cardiovascular abnormalities induced by microgravity. Major progress has been made during the first 18 months of the program: (1) We have developed an operational first-order computer model capable of simulating the cardiovascular response to orthostatic stress. The model consists of a lumped parameter hemodynamic model and a complete reflex control system. The latter includes cardiopulmonary and carotid sinus reflex limbs and interactions between the two. (2) We have modeled the physiologic stress of tilt table experiments and lower body negative pressure procedures (LBNP). We have verified our model's predictions by comparing them with experimental findings from the literature. (3) We have established collaborative efforts with leading investigators interested in experimental studies of orthostatic intolerance, cardiovascular control, and physiologic responses to space flight. (4) We have established a standardized method of transferring data to our laboratory from the ongoing NSBRI bedrest studies. We use this data to estimate input parameters to our model and compare our model predictions to actual data to further verify our model. (5) We are in the process of systematically simulating current hypotheses concerning the mechanism underlying orthostatic intolerance by matching our simulations to stand test data from astronauts pre- and post-flight. (6) We are in the process of developing a JAVA version of the simulator which will be distributed amongst the cardiovascular team members. Future work on this project involves modifications of the model to represent a rodent (rat) model, further evaluation of the bedrest astronaut and animal data, and systematic investigation of specific countermeasures.

Kamm, Roger D.

1999-01-01

21

Object-oriented modeling and simulation of the closed loop cardiovascular system by using SIMSCAPE.  

PubMed

The modeling of physiological systems via mathematical equations reflects the calculation procedure more than the structure of the real system modeled, with the simulation environment SIMULINK™ being one of the best suited to this strategy. Nevertheless, object-oriented modeling is spreading in current simulation environments through the use of the individual components of the model and its interconnections to define the underlying dynamic equations. In this paper we describe the use of the SIMSCAPE™ simulation environment in the object-oriented modeling of the closed loop cardiovascular system. The described approach represents a valuable tool in the teaching of physiology for graduate medical students. PMID:23428370

de Canete, J Fernandez; del Saz-Orozco, P; Moreno-Boza, D; Duran-Venegas, E

2013-05-01

22

A Delay Recruitment Model of the Cardiovascular Control System  

E-print Network

of ageing. 1 Introduction Control of blood pressure is critical to human health. Hypertension (high blood system, and use it to explore blood pressure and heart rate variability under short-term baroreflex of baroreflex health, using natural variations in heart rate and blood pressure data, requires a deep

McGuinness, Mark

23

A Functional Cardiovascular Model with Disorders  

Microsoft Academic Search

This paper introduces a functional model of the cardiovascular system that is capable of describing its behavior in normal as well as pathologic cases. The developed model includes all the main compartments of the circulatory system and also the baroreflex-feedback regulatory mechanism. The model response to the incorporation of two critical cardiovascular disorders namely hypertension and acute congestive heart failure

M. E. Hassan; M. A. El-Brawany; M. M. Sharaf

2005-01-01

24

A Closed-Loop Lumped Parameter Computational Model for Human Cardiovascular System  

NASA Astrophysics Data System (ADS)

For purpose of a better understanding of the behavior of the global hemodynamic interactions, a closed-loop lumped parameter computational model was developed for the human cardiovascular system with a detailed compartmental description of the heart and the main vascular circulations. Construction of the model was implemented based on a phenomenological characterization of hemodynamics using an electrical analog method and solution of the governing differential equations of the model was carried out by use of a fourth-order Runge-Kutta method. Most of the hemodynamic parameters predicted by the present model were either consonant with the clinical measurements or within reasonable physiological ranges. Furthermore, the present model was applied to predict the clinical cardiac hemodynamic characteristics observed in patients with heart abnormalities. Reasonable agreements between predictions and measurements indicate that the present computational model can serve as a useful assistant tool for computer-aided diagnosis and surgical treatment, as well as posttreatment prediction.

Liang, Fuyou; Liu, Hao

25

Optimization in Cardiovascular Modeling  

NASA Astrophysics Data System (ADS)

Fluid mechanics plays a key role in the development, progression, and treatment of cardiovascular disease. Advances in imaging methods and patient-specific modeling now reveal increasingly detailed information about blood flow patterns in health and disease. Building on these tools, there is now an opportunity to couple blood flow simulation with optimization algorithms to improve the design of surgeries and devices, incorporating more information about the flow physics in the design process to augment current medical knowledge. In doing so, a major challenge is the need for efficient optimization tools that are appropriate for unsteady fluid mechanics problems, particularly for the optimization of complex patient-specific models in the presence of uncertainty. This article reviews the state of the art in optimization tools for virtual surgery, device design, and model parameter identification in cardiovascular flow and mechanobiology applications. In particular, it reviews trade-offs between traditional gradient-based methods and derivative-free approaches, as well as the need to incorporate uncertainties. Key future challenges are outlined, which extend to the incorporation of biological response and the customization of surgeries and devices for individual patients.

Marsden, Alison L.

2014-01-01

26

Modeling high-order synchronization epochs and transitions in the cardiovascular system  

NASA Astrophysics Data System (ADS)

We study a system consisting of two coupled phase oscillators in the presence of noise. This system is used as a model for the cardiorespiratory interaction in wakefulness and anaesthesia. We show that longrange correlated noise produces transitions between epochs with different n:m synchronisation ratios, as observed in the cardiovascular system. Also, we see that, the smaller the noise (specially the one acting on the slower oscillator), the bigger the synchronisation time, exactly as happens in anaesthesia compared with wakefulness. The dependence of the synchronisation time on the couplings, in the presence of noise, is studied; such dependence is softened by low-frequency noise. We show that the coupling from the slow oscillator to the fast one (respiration to heart) plays a more important role in synchronisation. Finally, we see that the isolines with same synchronisation time seem to be a linear combination of the two couplings.

García-Álvarez, David; Bahraminasab, Alireza; Stefanovska, Aneta; McClintock, Peter V. E.

2007-12-01

27

Simulation of Left Atrial Function Using a Multi-Scale Model of the Cardiovascular System  

PubMed Central

During a full cardiac cycle, the left atrium successively behaves as a reservoir, a conduit and a pump. This complex behavior makes it unrealistic to apply the time-varying elastance theory to characterize the left atrium, first, because this theory has known limitations, and second, because it is still uncertain whether the load independence hypothesis holds. In this study, we aim to bypass this uncertainty by relying on another kind of mathematical model of the cardiac chambers. In the present work, we describe both the left atrium and the left ventricle with a multi-scale model. The multi-scale property of this model comes from the fact that pressure inside a cardiac chamber is derived from a model of the sarcomere behavior. Macroscopic model parameters are identified from reference dog hemodynamic data. The multi-scale model of the cardiovascular system including the left atrium is then simulated to show that the physiological roles of the left atrium are correctly reproduced. This include a biphasic pressure wave and an eight-shaped pressure-volume loop. We also test the validity of our model in non basal conditions by reproducing a preload reduction experiment by inferior vena cava occlusion with the model. We compute the variation of eight indices before and after this experiment and obtain the same variation as experimentally observed for seven out of the eight indices. In summary, the multi-scale mathematical model presented in this work is able to correctly account for the three roles of the left atrium and also exhibits a realistic left atrial pressure-volume loop. Furthermore, the model has been previously presented and validated for the left ventricle. This makes it a proper alternative to the time-varying elastance theory if the focus is set on precisely representing the left atrial and left ventricular behaviors. PMID:23755183

Pironet, Antoine; Dauby, Pierre C.; Paeme, Sabine; Kosta, Sarah; Chase, J. Geoffrey; Desaive, Thomas

2013-01-01

28

Laguerre-model blind system identification: cardiovascular dynamics estimated from multiple peripheral circulatory signals.  

PubMed

This paper presents a method for comparing multiple circulatory waveforms measured at different locations to improve cardiovascular parameter estimation from these signals. The method identifies the distinct vascular dynamics that shape each waveform signal, and estimates the common cardiac flow input shared by them. This signal-processing algorithm uses the Laguerre function series expansion for modeling the hemodynamics of each arterial branch, and identifies unknown parameters in these models from peripheral waveforms using multichannel blind system identification. An effective technique for determining the Laguerre base pole is developed, so that the Laguerre expansion captures and quickly converges to the intrinsic arterial dynamics observed in the two circulatory signals. Furthermore, a novel deconvolution method is developed in order to stably invert the identified dynamic models for estimating the cardiac output (CO) waveform from peripheral pressure waveforms. The method is applied to experimental swine data. A mean error of less than 5% with the measured peripheral pressure waveforms has been achieved using the models and excellent agreement between the estimated CO waveforms and the gold standard measurements have been obtained. PMID:16285393

McCombie, Devin B; Reisner, Andrew T; Asada, Haruhiko Harry

2005-11-01

29

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

PubMed

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

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

2014-11-01

30

[Cardiovascular system and aging].  

PubMed

Aging is one of the most important cardiovascular risk factors. Age-related morphologic changes in large resistance vessels include an intima-media-thickening and increased deposition of matrix substance, ultimately leading to a reduced compliance and an increased stiffness of the vessels. Aging of the heart is mainly characterized by an increase of the left ventricular mass in relation to the chamber volume and a decrease of diastolic function. There is some controversy in regard to the question if these changes in the vessel wall are the consequence of aging or if a decrease in physical activity is a major contributor of this process. With age the cardiovascular profile is changing. Whereas smoking is less prominent, arterial hypertension and diabetes mellitus are more often encountered. Primary and secondary prevention through cardiovascular risk factor management is also very important in the aging population due to the increased risk of acute vascular complications with age. Preventive measures have to include life style factor interventions as well as optimized drug therapy. There is no scientific evidence that vascular aging can be prevented by administration of supplements such as antioxidant vitamins. Aspirin is effective for cardiovascular prevention up to a higher age. Betablockers and ACE-inhibitors are generally underused in older patients after myocardial infarctions. Statins are effective in reducing cardiovascular complications up to an age of 80 years. Myocardial infarction in elderly patients is often characterized by atypical symptoms and may be even silent. Interventional therapy in elderly patients is as successful as in younger patients but has an increased complication rate. Ambulatory cardiac rehabilitation in elderly patients leads to significant improvements of physical capacity, well-being and quality of life and may help to prevent social isolation. PMID:16405288

Saner, H

2005-12-01

31

Conceptual modeling of cardiovascular sounds.  

PubMed

In this paper, it is shown that the main source of mechanical energy of cardiovascular (CV) system i.e., rhythmic heart contraction is transformed to the oscillations of the CV walls and blood flow, and finally CV acoustical waves. These waves propagate through both blood flow (hemodynamical pathways) and tissues (viscoelastical pathways) toward the skin. Nonetheless, the CV walls could be assumed as the source of acoustical waves, since they act as the interface between blood flows and other tissues including skin. After obtaining the approximate accelerations of CV walls from pressure-flow (PF) models, we also needed to model the viscoelastical pathways until the skin. Some improvements on PF models were fulfilled to present small variations of blood pressure such as dicrotic notch. The turbulence occurrence was also noticed to and conceptually modeled. The total homomorphic model could conceptually show the relations of CV sounds with CV characterizations and tissue specifications. Thus, it could be helpful to assess CV system in order to diagnose CV diseases via CV sounds. The CV sounds recorded from the skin of any place (e.g., chest or arm) could be simulated via this model, if the hemodynamical and viscoelastical parameters especially for the region under that place are obtained. PMID:17282696

Pouladian, Majid; Abbaspour Tehrani-Fard, Ali

2005-01-01

32

Cardiovascular Biology of the Incretin System  

PubMed Central

Glucagon-like peptide-1 (GLP-1) is an incretin hormone that enhances glucose-stimulated insulin secretion and exerts direct and indirect actions on the cardiovascular system. GLP-1 and its related incretin hormone, glucose-dependent insulinotropic polypeptide (GIP), are rapidly inactivated by the enzyme dipeptidyl peptidase 4 (DPP-4), a key determinant of incretin bioactivity. Two classes of medications that enhance incretin action, GLP-1R agonists and DPP-4 inhibitors, are used for the treatment of type 2 diabetes mellitus (T2DM). We review herein the cardiovascular biology of GLP-1R agonists and DPP-4 inhibitors, including direct and indirect effects on cardiomyocytes, blood vessels, adipocytes, the control of blood pressure and postprandial lipoprotein secretion. Both GLP-1R activation and DPP-4 inhibition exert multiple cardioprotective actions in preclinical models of cardiovascular dysfunction, and short term studies in human subjects appear to demonstrate modest yet beneficial actions on cardiac function in subjects with ischemic heart disease. Incretin-based agents control body weight, improve glycemic control with a low risk of hypoglycemia, decrease blood pressure, inhibit the secretion of intestinal chylomicrons, and reduce inflammation in preclinical studies. Nevertheless, there is limited information on the cardiovascular actions of these agents in patients with diabetes and established cardiovascular disease. Hence, a more complete understanding of the cardiovascular risk:benefit ratio of incretin-based therapies will require completion of long term cardiovascular outcome studies currently underway in patients with T2DM. PMID:22323472

Ussher, John R.; Drucker, Daniel J.

2012-01-01

33

Animal Models of Cardiovascular Diseases  

PubMed Central

Cardiovascular diseases are the first leading cause of death and morbidity in developed countries. The use of animal models have contributed to increase our knowledge, providing new approaches focused to improve the diagnostic and the treatment of these pathologies. Several models have been developed to address cardiovascular complications, including atherothrombotic and cardiac diseases, and the same pathology have been successfully recreated in different species, including small and big animal models of disease. However, genetic and environmental factors play a significant role in cardiovascular pathophysiology, making difficult to match a particular disease, with a single experimental model. Therefore, no exclusive method perfectly recreates the human complication, and depending on the model, additional considerations of cost, infrastructure, and the requirement for specialized personnel, should also have in mind. Considering all these facts, and depending on the budgets available, models should be selected that best reproduce the disease being investigated. Here we will describe models of atherothrombotic diseases, including expanding and occlusive animal models, as well as models of heart failure. Given the wide range of models available, today it is possible to devise the best strategy, which may help us to find more efficient and reliable solutions against human cardiovascular diseases. PMID:21403831

Zaragoza, Carlos; Gomez-Guerrero, Carmen; Martin-Ventura, Jose Luis; Blanco-Colio, Luis; Lavin, Begońa; Mallavia, Beńat; Tarin, Carlos; Mas, Sebastian; Ortiz, Alberto; Egido, Jesus

2011-01-01

34

[Experimental models of cardiovascular disease].  

PubMed

The present work describes clinically useful experimental models for the study of cardiovascular disease and emphasites the models used to determine the pathophysiologic mechanisms of atherosclerosis, as well as to evaluate the effects of nutritional and pharmacological products on the development of this complex inflammatory process present in many cardiovascular diseases. Animal models in which ahterosclerosis may be induced by dietary changes are reviewed, as well as those in which modification in one or more genes (knock-out and knock-in animals), or the incorporation of foreign genes from other species lead to early cardiovascular disease. On the other hand, some of the cell lines most frequently used in studying molecular mechanisms of atherosclerosis and assessment of substances with nutritional or pharmacological interest are considered. PMID:17416033

Gil Hernández, A; Ramírez Tortosa, M C; Aguilera García, M C; Mesa García, M D

2007-01-01

35

Bioengineering and the cardiovascular system  

PubMed Central

The development of the modern era of bioengineering and the advances in our understanding of the cardiovascular system have been intertwined over the past one-half century. This is true of bioengineering as an area for research in universities. Bioengineering is ultimately the beginning of a new engineering discipline, as well as a new discipline in the medical device industry. PMID:24688999

Nerem, Robert M

2013-01-01

36

The Gross Physiology of the Cardiovascular System  

NSDL National Science Digital Library

This site is the online text of Dr. Robert M. Anderson's book The Gross Physiology of the Cardiovascular System. Even though biomedical knowledge is continually advancing and becoming more specific, Anderson feels that it is important to "have a clear understanding of the gross mechanical function of the cardiovascular system as a whole." This resource is provided as a model to do just that. The text is well organized and easy to navigate; additionally, a video that provides a summary of the online text can be viewed online.

Anderson, Robert M.

37

MODELING BLOOD FLOW IN THE CARDIOVASCULAR  

E-print Network

MODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA325 ­ Spring 2013 Department of Mathematics (Greek),...; Two distinct types of blood were thought to exist: § Nutritive blood was thought to be made by the liver and carried through veins to the organs, where it was consumed § Vital blood was thought

Olufsen, Mette Sofie

38

MODELING BLOOD FLOW IN THE CARDIOVASCULAR  

E-print Network

MODELING BLOOD FLOW IN THE CARDIOVASCULAR SYSTEM MA432 ­ Spring 2013 Department of Mathematics (Greek),...; Two distinct types of blood were thought to exist: § "Nutritive blood" was thought to be made by the liver and carried through veins to the organs, where it was consumed § "Vital blood

Olufsen, Mette Sofie

39

CVSys: A Coordination Framework for Dynamic and Fully Distributed Cardiovascular Modeling and Simulation  

E-print Network

of providing insights to indirectly benefit cardiovascular health care. The complex cardiovascu- lar systemCVSys: A Coordination Framework for Dynamic and Fully Distributed Cardiovascular Modeling framework, CVSys, for dynamic and fully distributed cardiovascular simulation with natural behav- ior flow

California at Irvine, University of

40

Closed-loop real-time simulation model of hemodynamics and oxygen transport in the cardiovascular system  

PubMed Central

Background Computer technology enables realistic simulation of cardiovascular physiology. The increasing number of clinical surgical and medical treatment options imposes a need for better understanding of patient-specific pathology and outcome prediction. Methods A distributed lumped parameter real-time closed-loop model with 26 vascular segments, cardiac modelling with time-varying elastance functions and gradually opening and closing valves, the pericardium, intrathoracic pressure, the atrial and ventricular septum, various pathological states and including oxygen transport has been developed. Results Model output is pressure, volume, flow and oxygen saturation from every cardiac and vascular compartment. The model produces relevant clinical output and validation of quantitative data in normal physiology and qualitative directions in simulation of pathological states show good agreement with published data. Conclusion The results show that it is possible to build a clinically relevant real-time computer simulation model of the normal adult cardiovascular system. It is suggested that understanding qualitative interaction between physiological parameters in health and disease may be improved by using the model, although further model development and validation is needed for quantitative patient-specific outcome prediction. PMID:23842033

2013-01-01

41

Cardiovascular-Respiratory HUT Model including Optimal Control and Comparison to LBNP models  

E-print Network

Cardiovascular-Respiratory HUT Model including Optimal Control and Comparison to LBNP models Martin on the cardiovascular system when the body is in the upright position as compared to the supine position. This report introduces a model of the cardiovascular and respiratory system which is used to simulate orthostatic stress

Batzel, Jerry

42

Cardiovascular system simulation in biomedical engineering education.  

NASA Technical Reports Server (NTRS)

Use of complex cardiovascular system models, in conjunction with a large hybrid computer, in biomedical engineering courses. A cardiovascular blood pressure-flow model, driving a compartment model for the study of dye transport, was set up on the computer for use as a laboratory exercise by students who did not have the computer experience or skill to be able to easily set up such a simulation involving some 27 differential equations running at 'real time' rate. The students were given detailed instructions regarding the model, and were then able to study effects such as those due to septal and valve defects upon the pressure, flow, and dye dilution curves. The success of this experiment in the use of involved models in engineering courses was such that it seems that this type of laboratory exercise might be considered for use in physiology courses as an adjunct to animal experiments.

Rideout, V. C.

1972-01-01

43

Cardiovascular disease in systemic sclerosis  

PubMed Central

Cardiovascular (CV) system involvement is a frequent complication of autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). It still remains unclear if a premature atherosclerosis (ATS) occurs even in systemic sclerosis (SSc). Although microvascular disease is a hallmark of SSc, in the last few years a number of studies highlighted a higher prevalence of macrovascular disease in SSc patients in comparison to healthy individuals and these data have been correlated with a poorer prognosis. The mechanisms promoting ATS in SSc are not fully understood, but it is believed to be secondary to multi-system organ inflammation, endothelial wall damage and vasculopathy. Both traditional risk factors and endothelial dysfunction have been proposed to participate to the onset and progression of ATS in such patients. In particular, endothelial cell injury induced by anti-endothelial antibodies, ischemia/reperfusion damage, immune-mediated cytotoxicity represent the main causes of vascular injury together with an impaired vascular repair mechanism that determine a defective vasculogenesis. Aim of this review is to analyse both causes and clinical manifestations of macrovascular involvement and ATS in SSc.

Cannarile, Francesca; Valentini, Valentina; Mirabelli, Giulia; Alunno, Alessia; Terenzi, Riccardo; Luccioli, Filippo; Bartoloni, Elena

2015-01-01

44

Ultrafast CT and the cardiovascular system  

Microsoft Academic Search

Ultrafast computed tomography (CT) is a new imaging technique that relies on electron beam technology. Its rapid image acquisition speeds make it ideal for evaluating the cardiovascular system. The high-resolution, flow, and cine-modes are unique and provide complimentary information about cardiovascular anatomy, function, and flow dynamics. Ultrafast CT can provide quantitative measurements of cardiac output, ejection fraction, ventricular volumes, and

Mark S. Bleiweis; Demetrios Georgiou; Bruce H. Brundage

1992-01-01

45

Efficacy of Female Rat Models in Translational Cardiovascular Aging Research  

PubMed Central

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

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

2014-01-01

46

A multi-scale cardiovascular system model can account for the load-dependence of the end-systolic pressure-volume relationship  

PubMed Central

Background The end-systolic pressure-volume relationship is often considered as a load-independent property of the heart and, for this reason, is widely used as an index of ventricular contractility. However, many criticisms have been expressed against this index and the underlying time-varying elastance theory: first, it does not consider the phenomena underlying contraction and second, the end-systolic pressure volume relationship has been experimentally shown to be load-dependent. Methods In place of the time-varying elastance theory, a microscopic model of sarcomere contraction is used to infer the pressure generated by the contraction of the left ventricle, considered as a spherical assembling of sarcomere units. The left ventricle model is inserted into a closed-loop model of the cardiovascular system. Finally, parameters of the modified cardiovascular system model are identified to reproduce the hemodynamics of a normal dog. Results Experiments that have proven the limitations of the time-varying elastance theory are reproduced with our model: (1) preload reductions, (2) afterload increases, (3) the same experiments with increased ventricular contractility, (4) isovolumic contractions and (5) flow-clamps. All experiments simulated with the model generate different end-systolic pressure-volume relationships, showing that this relationship is actually load-dependent. Furthermore, we show that the results of our simulations are in good agreement with experiments. Conclusions We implemented a multi-scale model of the cardiovascular system, in which ventricular contraction is described by a detailed sarcomere model. Using this model, we successfully reproduced a number of experiments that have shown the failing points of the time-varying elastance theory. In particular, the developed multi-scale model of the cardiovascular system can capture the load-dependence of the end-systolic pressure-volume relationship. PMID:23363818

2013-01-01

47

The Gross Physiology of the Cardiovascular System  

NSDL National Science Digital Library

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.

Dr. Robert M Anderson (University of Arizona)

2012-01-20

48

Cardiovascular Toxicities from Systemic Breast Cancer Therapy  

PubMed Central

Cardiovascular toxicity is unfortunately a potential short- or long-term sequela of breast cancer therapy. Both conventional chemotherapeutic agents such as anthracyclines and newer targeted agents such as trastuzumab can cause varying degrees of cardiac dysfunction. Type I cardiac toxicity is dose-dependent and irreversible, whereas Type II is not dose-dependent and is generally reversible with cessation of the drug. In this review, we discuss what is currently known about the cardiovascular effects of systemic breast cancer treatments, with a focus on the putative mechanisms of toxicity, the role of biomarkers, and potential methods of preventing and minimizing cardiovascular complications. PMID:25538891

Guo, Shuang; Wong, Serena

2014-01-01

49

Cardiovascular magnetic resonance in systemic hypertension  

PubMed Central

Systemic hypertension is a highly prevalent potentially modifiable cardiovascular risk factor. Imaging plays an important role in the diagnosis of underlying causes for hypertension, in assessing cardiovascular complications of hypertension, and in understanding the pathophysiology of the disease process. Cardiovascular magnetic resonance (CMR) provides accurate and reproducible measures of ventricular volumes, mass, function and haemodynamics as well as uniquely allowing tissue characterization of diffuse and focal fibrosis. In addition, CMR is well suited for exclusion of common secondary causes for hypertension. We review the current and emerging clinical and research applications of CMR in hypertension. PMID:22559053

2012-01-01

50

Acute cardiovascular response to high altitude in healthy and anemic subjects: a mathematical model  

Microsoft Academic Search

The acute cardiovascular response to hypocapnic hypoxia (simulating high altitude condition) is investigated both in healthy and anemic subjects by using a mathematical model of short-term cardiovascular regulation. The model includes a description of the cardiovascular system and several control mechanisms triggered by changes in blood gas content. Hypoxia produces significant rise in cardiac output and heart rate, while arterial

E. Magosso; M. Ursino

2003-01-01

51

Cardiovascular modelling at IMFUFA Jesper Kampmann Larsen1, Viggo Andreasen1, Heine Larsen1, Mette Sofie  

E-print Network

Cardiovascular modelling at IMFUFA Jesper Kampmann Larsen1, Viggo Andreasen1, Heine Larsen1, Mette: The human cardiovascular system including its control mechanisms and on fluid dynamics and valveless flow developments in cardiovascular modelling at IMFUFA. As an alternative to the widespread use of electrical

Olufsen, Mette Sofie

52

On the Track of Syncope induced by Orthostatic Stress -Feedback Mechanisms Regulating the Cardiovascular System  

E-print Network

the Cardiovascular System Ottesen JT.* and Olufsen MS.** *Roskilde University, 4000 Roskilde, Denmark (Tel: (+45 4674-mail: msolufse@unity.ncsu.edu) Abstract: A physiological realistic model of the controlled cardiovascular system. It turns out that this mechanical effect is significant. Keywords: Cardiovascular, control, sit

Olufsen, Mette Sofie

53

Feedback control of mean aortic pressure in a dynamic model of the cardiovascular system.  

PubMed

Orbital measurements of the cardiac function of Space Shuttle crew members have shown an initial increase in cardiac stroke volume upon entry into weightlessness, followed by a gradual reduction in stroke volume to a level approximately 15% less than preflight values. In an effort to explain this response, it was hypothesized that gravity plays a role in cardiac filling. A mock circulatory system was designed to investigate this effect. Preliminary studies carried out with this system on the NASA KC-135 aircraft, which provides brief periods of weightlessness, showed a strong correlation between cardiac filling, stroke volume, and the presence or absence of gravity. The need for extended periods of high quality zero gravity was identified to verify this observation. To accomplish this, the aircraft version of the experiment was reduced in size and fully automated for eventual integration into a Get Away Special canister to conduct an orbital version of the experiment. This article describes the automated system, as well as the development and implementation of a control algorithm for the servoregulation of the mean aortic pressure in the orbital experiment. Three nonlinearities that influence the ability of the apparatus to regulate to a mean aortic pressure of 95 mm Hg were identified and minimized. In preparation for a Space Shuttle flight, the successful function of the servoregulatory scheme was demonstrated during ground tests and additional test flights aboard the KC-135. The control algorithm was successful in carrying out the experimental protocol, including regulation of mean aortic pressure. The algorithm could also be used for the automated operation of long-term tests of circulatory support systems, which may require a scheduled cycling of the pumping conditions on a daily basis. PMID:10593691

O'Leary, D S; Pantalos, G M; Sharp, M K

1999-01-01

54

Cardiovascular Interactions: An Interactive Tutorial and Mathematical Model  

NSDL National Science Digital Library

The maintenance of an adequate cardiac output and systemic arterial blood pressure is a complex process with intricacies that are often difficult to understand. Cardiovascular Interactions is an active learning tool that demonstrates the interactions between the functions of the heart and peripheral circulation. This learning package consists of a Lab Book, a Model, and an Information file. The Lab Book is an interactive tutorial for exploring the relative influences of parameter changes on the cardiovascular system under normal, stressful, or pathophysiological conditions. The learners are guided to predict the direction and relative magnitude of changes of key variables in the cardiovascular system, evaluate the accuracy of their predictions, and describe the cause-and-effect mechanisms involved. Consequences of heart failure, hemorrhage, exercise, and changes in intrathoracic pressure can be explored. The results obtained in the Lab Book are based on a five-compartment mathematical Model, which reflects our current understanding of the basic control of the cardiovascular system. The Model was designed to be complex enough to be realistic, yet not so complex as to be overwhelming. An Information File contains definitions and descriptions of classical physiology about key concepts, including figures, and a detailed description of the Model. Hypertext tags embedded in the Lab Book are used to access the Information File. The Cardiovascular Interactions learning package was designed to run from its CD and so does not need to be installed.

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

2002-06-01

55

The Heart of Our Cardiovascular System  

NSDL National Science Digital Library

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.

2014-09-18

56

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

PubMed

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

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

2014-04-01

57

Mathematical biomarkers for the autonomic regulation of cardiovascular system  

PubMed Central

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

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

2013-01-01

58

MODELING CARDIOVASCULAR AND RESPIRATORY DYNAMICS IN CONGESTIVE HEART FAILURE  

E-print Network

pathophysiological links between sleep-related breathing disorders and cardiovascular diseases have recently receivedMODELING CARDIOVASCULAR AND RESPIRATORY DYNAMICS IN CONGESTIVE HEART FAILURE LAURA M. ELLWEIN1. This study develops a coupled cardiovascular-respiratory model that predicts cerebral blood flow velocity

Olufsen, Mette Sofie

59

Estimation of cardiac output and systemic vascular resistance using a multivariate regression model with features selected from the finger photoplethysmogram and routine cardiovascular measurements  

PubMed Central

Background Cardiac output (CO) and systemic vascular resistance (SVR) are two important parameters of the cardiovascular system. The ability to measure these parameters continuously and noninvasively may assist in diagnosing and monitoring patients with suspected cardiovascular diseases, or other critical illnesses. In this study, a method is proposed to estimate both the CO and SVR of a heterogeneous cohort of intensive care unit patients (N=48). Methods Spectral and morphological features were extracted from the finger photoplethysmogram, and added to heart rate and mean arterial pressure as input features to a multivariate regression model to estimate CO and SVR. A stepwise feature search algorithm was employed to select statistically significant features. Leave-one-out cross validation was used to assess the generalized model performance. The degree of agreement between the estimation method and the gold standard was assessed using Bland-Altman analysis. Results The Bland-Altman bias ±precision (1.96 times standard deviation) for CO was -0.01 ±2.70 L min-1 when only photoplethysmogram (PPG) features were used, and for SVR was -0.87 ±412 dyn.s.cm-5 when only one PPG variability feature was used. Conclusions These promising results indicate the feasibility of using the method described as a non-invasive preliminary diagnostic tool in supervised or unsupervised clinical settings. PMID:23452705

2013-01-01

60

Cardiovascular response to dynamic aerobic exercise: A methematical model  

Microsoft Academic Search

An original mathematical model of the cardiovascular response to dynamic exercise is presented. It includes the pulsating\\u000a heart, the pulmonary and systemic circulation, a separate description of the vascular bed in active tissues, the local metabolic\\u000a vasodilation in these tissues and the mechanical effects of muscular contractions on venous return. Moreover, the model provides\\u000a a description of the ventilatory response

E. Magosso; M. Ursino

2002-01-01

61

Cardiovascular defects in a mouse model of HOXA1 syndrome  

E-print Network

Cardiovascular defects in a mouse model of HOXA1 syndrome Nadja Makki and Mario R. Capecchi Howard Brainstem Dysgenesis Syndrome, Bosley-Salih-Alorainy Syndrome), can cause severe cardiovascular to explore the developmental causes of the human disease. In this study, we identify severe cardiovascular

Capecchi, Mario R.

62

A Pulsatile Cardiovascular Computer Model for Teaching Heart-Blood Vessel Interaction.  

ERIC Educational Resources Information Center

Describes a model which gives realistic predictions of pulsatile pressure, flow, and volume events in the cardiovascular system. Includes computer oriented laboratory exercises for veterinary and graduate students; equations of the dynamic and algebraic models; and a flow chart for the cardiovascular teaching program. (JN)

Campbell, Kenneth; And Others

1982-01-01

63

Cardiovascular Engineering: An International Journal, Vol. 4, No. 1, March 2004 ( C 2004) Modeling Cerebral Blood Flow Control During Posture  

E-print Network

Cardiovascular Engineering: An International Journal, Vol. 4, No. 1, March 2004 ( C 2004) Modeling model against experimental data from a young subject. Key words: cardiovascular system; cerebral blood-term cardiovascular regulation of blood flow to the brain is essential for development of new strategies to prevent

Olufsen, Mette Sofie

64

An electro-fluid-dynamic simulator for the cardiovascular system.  

PubMed

This work presents the initial studies and the proposal for a cardiovascular system electro-fluid-dynamic simulator to be applied in the development of left ventricular assist devices (LVADs). The simulator, which is being developed at University Sao Judas Tadeu and at Institute Dante Pazzanese of Cardiology, is composed of three modules: (i) an electrical analog model of the cardiovascular system operating in the PSpice electrical simulator environment; (ii) an electronic controller, based on laboratory virtual instrumentation engineering workbench (LabVIEW) acquisition and control tool, which will act over the physical simulator; and (iii) the physical simulator: a fluid-dynamic equipment composed of pneumatic actuators and compliance tubes for the simulation of active cardiac chambers and big vessels. The physical simulator (iii) is based on results obtained from the electrical analog model (i) and physiological parameters. PMID:18370952

Felipini, Celso Luiz; de Andrade, Aron José Pazin; Lucchi, Júlio César; da Fonseca, Jeison Willian Gomes; Nicolosi, Denys

2008-04-01

65

Physiological homology between Drosophila melanogaster and vertebrate cardiovascular systems  

E-print Network

The physiology of the Drosophila melanogaster cardiovascular system remains poorly characterized compared with its vertebrate counterparts. Basic measures of physiological performance remain unknown. It also is unclear ...

Choma, Michael A.

66

Space weather and cardiovascular system. New findings  

NASA Astrophysics Data System (ADS)

Researches of last two decades have shown that the cardiovascular system represents the most probable target for influence of helio - and geomagnetic activity. Both cardiovascular system and system of blood are connected very closely: one system cannot exist without another. For the same reason the effects perceived by one system, are easily transferred to another. Laboratory tests such as blood coagulation, platelet aggregation, and capillary blood velocity (CBV) performed in Scientific Clinical Center JSC "Russian Railways in patients suffering from coronary heart disease (CHD) revealed a high dependence with a level of geomagnetic activity. Results of these and other findings allow to assume that blood itself can be a sensor of geomagnetic fields variations because erythrocytes, platelets, and leucocytes bearing electric charge on membranes, and in a comparable magnetic field can change as own properties and properties of blood flow. It is interesting that not only geomagnetic disturbances, but also the periods of very quiet geomagnetic conditions affect a capillary blood velocity, slowing down it. It was shown during long-term experiment with isolation named 'MARS-500' in spatial facility of the Institute of Biomedical Problems in Moscow as imitation of an extended space mission to Mars. Using digital capillaroscope 'Russia', two crewmembers - medical doctors made records of microcirculation parameters at themselves and other four participants of 'Martian' team. Capillary records were performed before, during, and after period of isolation in medical module of MARS-500 facility. At the period of experiment nobody of crewmembers knew about real geomagnetic conditions. In days of active geomagnetic conditions average CBV has registered as 389 ± 167 ?m/s, that statistically significant (p

Gurfinkel, Yury; Breus, Tamara

2014-05-01

67

76 FR 62164 - VASRD Improvement Forum-Updating Disability Criteria for the Respiratory System, Cardiovascular...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Respiratory System, Cardiovascular System, Hearing...Nose and Throat Diseases AGENCY: Department...Respiratory System, Cardiovascular System, Hearing...Nose and Throat Diseases. The purpose...2) the Cardiovascular System (38 CFR...Nose and Throat Diseases (38 CFR...

2011-10-06

68

The human cardiovascular system during space flight  

NASA Astrophysics Data System (ADS)

Purpose of the work is to analyze and to summarize the data of investigations into human hemodynamics performed over 20 years aboard orbital stations Salyut-7 and Mir with participation of 26 cosmonauts on space flights (SF) from 8 to 438 days in duration. The ultrasonic techniques and occlusive plethysmography demonstrated dynamics of changes in the cardiovascular system during SF of various durations. The parameters of general hemodynamics, the pumping function of the heart and arterial circulation in the brain remained stable in all the space flights; however, there were alterations in peripheral circulation associated with blood redistribution and hypovolemie in microgravity. The anti-gravity distribution of the vascular tone decayed gradually as unneeded. The most considerable changes were observed in leg vessels, equally in arteries (decrease in resistance) and veins (increase in maximum capacity). The lower body negative pressure test (LBNP) revealed deterioration of the gravity-dependent reactions that changed for the worse as SF duration extended. The cardiovascular deconditioning showed itself as loss of descent acceleration tolerance and orthostatic instability in the postflight period.

Grigoriev, A. I.; Kotovskaya, A. R.; Fomina, G. A.

2011-05-01

69

Degradation Model of Bioabsorbable Cardiovascular Stents  

PubMed Central

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

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

2014-01-01

70

Corticosteroids: do they damage the cardiovascular system?  

PubMed Central

Since their introduction for the treatment of rheumatoid arthritis, corticosteroids have become widely used as effective agents in the control of inflammatory diseases. Although there have been undoubted benefits upon mortality in diseases such as systemic lupus erythematosus, many patients survive only to suffer a high incidence of premature atherosclerosis. There is also evidence of increased rates of vascular mortality in other corticosteroid-treated diseases, such as rheumatoid arthritis, reversible airways obstruction and transplant recipients. Possible mechanisms of damage include elevated blood pressure, impaired glucose tolerance, dyslipidaemia, and imbalances in thrombosis and fibrinolysis. This paper reviews the clinical evidence supporting the contention that there is an excess cardiovascular mortality in steroid-treated patients and the underlying mechanisms, and points to further areas of research. PMID:7870631

Maxwell, S. R.; Moots, R. J.; Kendall, M. J.

1994-01-01

71

Predictions of cardiovascular responses during STS reentry using mathematical models  

NASA Technical Reports Server (NTRS)

The physiological adaptation to weightless exposure includes cardiovascular deconditioning arising in part from a loss of total circulating blood volume and resulting in a reduction of orthostatic tolerance. The crew of the Shuttle orbiter are less tolerant to acceleration forces in the head-to-foot direction during the reentry phase of the flight at a time they must function at a high level of performance. The factors that contribute to orthostatic intolerance during and following reentry and to predict the likelihood of impaired crew performance are evaluated. A computer simulation approach employing a mathematical model of the cardiovascular system is employed. It is shown that depending on the severity of blood volume loss, the reentry acceleration stress may be detrimental to physiologic function and may place the physiologic status of the crew near the borderline of some type of impairment. They are in agreement with conclusions from early ground-based experiments and from observations of early Shuttle flights.

Leonard, J. I.; Srinivasan, R.

1985-01-01

72

Regulation of sympathetic nervous system function after cardiovascular deconditioning  

NASA Technical Reports Server (NTRS)

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.

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

2001-01-01

73

Olive oil and the cardiovascular system  

Microsoft Academic Search

Olive oil is the primary source of fat in the Mediterranean diet which is associated with a low mortality for cardiovascular disease. In spite of this, data concerning olive oil consumption and primary end points for cardiovascular disease are scarce. However, a large body of knowledge exists providing evidence of the benefits of olive oil consumption on secondary end points

Mar ´ őa-Isabel Covas

2007-01-01

74

Real-time lumped parameter modeling of cardiovascular dynamics using electrocardiogram signals: toward virtual cardiovascular instruments.  

PubMed

We present an approach to deriving a real-time, lumped parameter cardiovascular dynamics model that uses features extracted from online electrocardiogram (ECG) signal recordings to generate certain surrogate hemodynamic signals. The model represents the coupled dynamics of the heart chambers, valves, and pulmonary and systemic blood circulation loops in the form of nonlinear differential equations. The features extracted from ECG signals were used to estimate the timings and amplitudes of the atrioventricular activation input functions as well as other model parameters that capture the effect of cardiac morphological and physiological characteristics. The model was tested using hemodynamic signals from the PhysioNet MGH/MF Waveform database. The results suggest that the model can capture the salient time and frequency patterns of the measured central venous pressure, pulmonary arterial pressure, and respiratory impedance signals (R(2) > 0.65). We have developed a method based on Anderson-Darling statistic and Kullback-Leibler divergence to compare the clinical measures (i.e., systolic and diastolic pressures) estimated from model waveform-extrema with those from actual measurements. The test statistics of the model waveform-extrema were statistically indistinguishable from the measured values with beat-to-beat rejection rates of 10%. The results indicate the potential of a virtual instrument that uses the model-derived signals for clinical diagnosis in lieu of expensive instrumentation. PMID:23559024

Le, Trung Q; Bukkapatnam, Satish T S; Komanduri, Ranga

2013-08-01

75

Model-Referenced Cardiovascular Circulatory Simulator: Construction and Control.  

PubMed

Physiological feasibility is the most important requirement for cardiovascular circulatory simulators (CCSs). However, previous simulators have been validated by a comparison with specific human data sets, which are valid only for very limited conditions, and so it is difficult to validate the fidelity of a CCS for various body conditions. To overcome this critical limitation, we propose a model-referenced CCS that reproduces the behavior of an electrical-analog model of the cardiovascular circulatory system, for which physiological fidelity is well established over a wide range. In this study, the electrical-analog reference model was realized in the hardware simulator using fluidic element modeling and by the feedback control of a mock ventricle. The proposed simulator showed a good match with the reference model behavior, and its physiological validity was thereby verified. The proposed simulator is able to show responsiveness to various body conditions as well. To the best of the author's knowledge, this is the first report of an in vitro CCS verified to be consistent with reference model behavior. PMID:25345617

Gwak, Kwan-Woong

2014-10-27

76

Gravitational Force and the Cardiovascular System  

NASA Technical Reports Server (NTRS)

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.

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

1991-01-01

77

L-arginine and cardiovascular system.  

PubMed

L-arginine is a basic endogenous amino acid. Its significant metabolic role as the product of ammonia detoxification, the urea cycle metabolite, the precursor of proteins, ornithine, urea and creatinine, and the amino acid involved in the formation of active enzyme centers was very well established. The current interest in this amino acid refers mainly to its close relation with an important signal molecule nitric oxide (NO). Literature review demonstrates that L-arginine, the only substrate of the NO production, affects cardiovascular system (blood vessels and heart). The majority of experimental and clinical studies clearly show a beneficial effect of L-arginine on endothelium in conditions associated with its hypofunction and thus with reduced NO synthesis. Some clinical studies involving healthy volunteers or patients suffering from hypertension and diabetes indicate that it may also regulate vascular hemostasis. Moreover, experiments performed on animals and in vitro data also suggest that L-arginine may have a complex antiaggregatory, anticoagulatory and profibrinolytic effect. Therefore, a novel therapeutic potential of L-arginine should be taken into consideration. PMID:15849373

Cylwik, Dorota; Mogielnicki, Andrzej; Buczko, W?odzimierz

2005-01-01

78

Adiponectin Actions in the Cardiovascular System  

PubMed Central

Obesity is strongly associated with the pathogenesis of type 2 diabetes, hypertension, and cardiovascular disease. Levels of the hormone adiponectin are downregulated in obese individuals, and several experimental studies show that adiponectin protects against the development of various obesity-related metabolic and cardiovascular diseases. Adiponectin exhibits favorable effects on atherogenesis, endothelial function, and vascular remodeling by modulation of signaling cascades in cells of the vasculature. More recent findings have shown that adiponectin directly affects signaling in cardiac cells and is beneficial in the setting of pathological cardiac remodeling and acute cardiac injury. Several of these effects of adiponectin have been attributed to the activation of the 5’ AMP-activated protein kinase signaling cascade and other signaling proteins. This review will discuss epidemiological and experimental studies that have elucidated the role of adiponectin in a variety of cardiovascular diseases. PMID:17140553

Hopkins, Teresa A.; Ouchi, Noriyuki; Shibata, Rei; Walsh, Kenneth

2007-01-01

79

Is the cardiovascular system a therapeutic target for cannabidiol?  

PubMed

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

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

2013-02-01

80

Physiological system integrations with emphasis on the respiratory-cardiovascular system  

NASA Technical Reports Server (NTRS)

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.

Gallagher, R. R.

1975-01-01

81

Large Blood Vessels 1.1 Introduction --The Cardiovascular System  

E-print Network

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

Luo, Xiaoyu

82

Bench to Bedside Primer: The Cardiovascular System and Hypertension  

NSDL National Science Digital Library

This bench-to-bedside is a four-page ĂÂprimerĂÂ (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 SocietyĂÂs 2011 Frontiers Online in Physiology Program. For more information on this program, please visit www.frontiersinphys.org.

Jannette Moehlman (Dakota Middle School)

2011-10-07

83

Bench to Bedside Primer: The Cardiovascular System and Heart Arrhythmia  

NSDL National Science Digital Library

This bench-to-bedside is a four-page ĂÂprimerĂÂ (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 SocietyĂÂs 2011 Frontiers Online in Physiology Program. For more information on this program, please visit www.frontiersinphys.org.

Cora James (Haskell High School)

2011-10-07

84

A Cardiovascular Mathematical Model of Graded Head-Up Tilt  

PubMed Central

A lumped parameter model of the cardiovascular system has been developed and optimized using experimental data obtained from 13 healthy subjects during graded head-up tilt (HUT) from the supine position to . The model includes descriptions of the left and right heart, direct ventricular interaction through the septum and pericardium, the systemic and pulmonary circulations, nonlinear pressure volume relationship of the lower body compartment, arterial and cardiopulmonary baroreceptors, as well as autoregulatory mechanisms. A number of important features, including the separate effects of arterial and cardiopulmonary baroreflexes, and autoregulation in the lower body, as well as diastolic ventricular interaction through the pericardium have been included and tested for their significance. Furthermore, the individual effect of parameter associated with heart failure, including LV and RV contractility, baseline systemic vascular resistance, pulmonary vascular resistance, total blood volume, LV diastolic stiffness and reflex gain on HUT response have also been investigated. Our fitted model compares favorably with our experimental measurements and published literature at a range of tilt angles, in terms of both global and regional hemodynamic variables. Compared to the normal condition, a simulated congestive heart failure condition produced a blunted response to HUT with regards to the percentage changes in cardiac output, stroke volume, end diastolic volume and effector response (i.e., heart contractility, venous unstressed volume, systemic vascular resistance and heart rate) with progressive tilting. PMID:24204817

Lim, Einly; Chan, Gregory S. H.; Dokos, Socrates; Ng, Siew C.; Latif, Lydia A.; Vandenberghe, Stijn; Karunanithi, Mohan; Lovell, Nigel H.

2013-01-01

85

Obesity May Shut Down Circadian Clock in the Cardiovascular System  

NSDL National Science Digital Library

Researchers at the Georgia Health Sciences University in Augusta have found that a master clock gene ĂÂ which regulates the cardiovascular system ĂÂ 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.

APS Communications Office (American Physiological Society Communications Office)

2011-04-10

86

Computer modeling of cardiovascular fluidstructure interactions with the deforming-spatial-domain/stabilized  

E-print Network

a number of cardiovascular diseases includ- ing atherosclerosis and aneurysm. Since resolving phenomena between the cardiovascular diseases and the hemodynamic factors. We have devel- oped a computer modeling of cardiovascular diseases. Ă? 2005 Elsevier B.V. All rights reserved. Keywords: Cardiovascular disease; Fluid

Tezduyar, Tayfun E.

87

The emerging role of the endocannabinoid system in cardiovascular disease  

PubMed Central

Endocannabinoids are endogenous bioactive lipid mediators present both in the brain and various peripheral tissues, which exert their biological effects via interaction with specific G-protein-coupled cannabinoid receptors, the CB1 and CB2. Pathological overactivation of the endocannabinoid system (ECS) in various forms of shock and heart failure may contribute to the underlying pathology and cardiodepressive state by the activation of the cardiovascular CB1 receptors. Furthermore, tonic activation of CB1 receptors by endocannabinoids has also been implicated in the development of various cardiovascular risk factors in obesity/metabolic syndrome and diabetes, such as plasma lipid alterations, abdominal obesity, hepatic steatosis, inflammation, and insulin and leptin resistance. In contrast, activation of CB2 receptors in immune cells exerts various immunomodulatory effects, and the CB2 receptors in endothelial and inflammatory cells appear to limit the endothelial inflammatory response, chemotaxis, and inflammatory cell adhesion and activation in atherosclerosis and reperfusion injury. Here, we will overview the cardiovascular actions of endocannabinoids and the growing body of evidence implicating the dysregulation of the ECS in a variety of cardiovascular diseases. We will also discuss the therapeutic potential of the modulation of the ECS by selective agonists/antagonists in various cardiovascular disorders associated with inflammation and tissue injury, ranging from myocardial infarction and heart failure to atherosclerosis and cardiometabolic disorders. PMID:19357846

2009-01-01

88

Hydroxybenzoic acid isomers and the cardiovascular system  

PubMed Central

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

2014-01-01

89

Hydroxybenzoic acid isomers and the cardiovascular system.  

PubMed

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

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

2014-01-01

90

Validity of Cardiovascular Risk Prediction Models in Kidney Transplant Recipients  

PubMed Central

Background. Predicting cardiovascular risk is of great interest in renal transplant recipients since cardiovascular disease is the leading cause of mortality. Objective. To conduct a systematic review to assess the validity of cardiovascular risk prediction models in this population. Methods. Five databases were searched (MEDLINE, EMBASE, SCOPUS, CINAHL, and Web of Science) and cohort studies with at least one year of follow-up were included. Variables that described population characteristics, study design, and prognostic performance were extracted. The Quality in Prognostic Studies (QUIPS) tool was used to evaluate bias. Results. Seven studies met the criteria for inclusion, of which, five investigated the Framingham risk score and three used a transplant-specific model. Sample sizes ranged from 344 to 23,575, and three studies lacked sufficient event rates to confidently reach conclusion. Four studies reported discrimination (as measured by c-statistic), which ranged from 0.701 to 0.75, while only one risk model was both internally and externally validated. Conclusion. The Framingham has underestimated cardiovascular events in renal transplant recipients, but these studies have not been robust. A risk prediction model has been externally validated at least on one occasion, but comprehensive validation in multiple cohorts and impact analysis are recommended before widespread clinical application is advocated. PMID:24977223

Stewart, Samuel Alan; Shoker, Ahmed

2014-01-01

91

Electronic circuit detects left ventricular ejection events in cardiovascular system  

NASA Technical Reports Server (NTRS)

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.

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

1972-01-01

92

Patient-specific modeling of cardiovascular and respiratory dynamics during hypercapnia  

PubMed Central

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

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

2014-01-01

93

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

Microsoft Academic Search

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,

Jean-Baptiste Mathieu; Gilles Beaudoin; Sylvain Martel

2006-01-01

94

Cardiovascular disease in systemic sclerosis - an emerging association?  

PubMed Central

Microvascular disease is a prominent feature of systemic sclerosis (SSc) and leads to Raynaud's phenomenon, pulmonary arterial hypertension, and scleroderma renal crisis. The presence of macrovascular disease is less well established, and, in particular, it is not known whether the prevalence of coronary heart disease in SSc is increased. Furthermore, in terms of cardiac involvement in SSc, there remains conjecture about the relative contributions of atherosclerotic macrovascular disease and myocardial microvascular disease. In this review, we summarize the literature describing cardiovascular disease in SSc, discuss the pathophysiological mechanisms common to SSc and atherosclerosis, and review the surrogate markers of cardiovascular disease which have been examined in SSc. Proposed mediators of the vasculopathy of SSc which have also been implicated in atherosclerosis include endothelial dysfunction, a reduced number of circulating endothelial progenitor cells, and an increased number of microparticles. Excess cardiovascular risk in SSc is suggested by increased arterial stiffness and carotid intima thickening and reduced flow-mediated dilatation. Cohort studies of adequate size are required to resolve whether this translates into an increased incidence of cardiovascular events in patients with SSc. PMID:21888685

2011-01-01

95

Editorial: engineering approaches to study cardiovascular physiology: modeling, estimation, and signal processing  

E-print Network

With cardiovascular diseases being among the main causes of death in the world, quantitative modeling, assessment and monitoring of cardiovascular dynamics, and functioning play a critical role in bringing important ...

Chen, Zhe

96

Cardiovascular Changes in Animal Models of Metabolic Syndrome  

PubMed Central

Metabolic syndrome has been defined as a group of risk factors that directly contribute to the development of cardiovascular disease and/or type 2 diabetes. Insulin resistance seems to have a fundamental role in the genesis of this syndrome. Over the past years to the present day, basic and translational research has used small animal models to explore the pathophysiology of metabolic syndrome and to develop novel therapies that might slow the progression of this prevalent condition. In this paper we discuss the animal models used for the study of metabolic syndrome, with particular focus on cardiovascular changes, since they are the main cause of death associated with the condition in humans. PMID:23691518

Lehnen, Alexandre M.; Rodrigues, Bruno; Irigoyen, Maria Cláudia; De Angelis, Kátia; Schaan, Beatriz D'Agord

2013-01-01

97

Risk Factors for Cardiovascular Disease in Systemic Lupus Erythematosus  

Microsoft Academic Search

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

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

2010-01-01

98

Clinical Application of Stem Cells in the Cardiovascular System  

Microsoft Academic Search

\\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

Christof Stamm; Kristin Klose; Yeong-Hoon Choi

2010-01-01

99

competency Course Objective 1 1a Describe the pathophysiology of common and major diseases of the cardiovascular organ system.  

E-print Network

of common and major diseases of the cardiovascular organ system. 2 1a,1b Recognize abnormalities of these mechanisms produce important cardiovascular diseases. 3 1c Describe of the common cardiovascular disease, including behavioral, pharmacological, and interventional

Myers, Lawrence C.

100

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

NSDL National Science Digital Library

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.

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

2007-03-01

101

A stochastic modelling framework for the reconstruction of cardiovascular signals.  

PubMed

This paper presents a common stochastic modelling framework for physiological signals which allows patient simulation following a synthesis-by-analysis approach. Within this framework, we propose a general model-based methodology able to reconstruct missing or artifacted signal intervals in cardiovascular monitoring applications. The proposed model consists of independent stages which provide high flexibility to incorporate signals of different nature in terms of shape, cross-correlation and variability. The reconstruction methodology is based on model sampling and selection based on a wide range of boundary conditions, which include prior information. Results on real data show how the proposed methodology fits the particular approaches presented so far for electrocardiogram (ECG) reconstruction and how a simple extension within the framework can significantly improve their performance. PMID:25570049

Martin-Martinez, Diego; Casaseca-de-la-Higuera, Pablo; Martin-Fernandez, Marcos; Amira, Abbes; Chunbo Luo; Grecos, Christos; Alberola-Lopez, Carlos

2014-08-01

102

Psoriasis is a systemic disease with multiple cardiovascular and metabolic comorbidities.  

PubMed

There is evidence that patients with moderate to severe psoriasis have an increased risk of conditions such as cardiovascular disease, obesity, diabetes mellitus, and metabolic syndrome. The precise mechanisms underlying the observed increase in cardiovascular disease in psoriasis remain to be defined but inflammatory pathways mutual to both conditions are probably involved. Suppression of systemic inflammation in psoriasis could help reduce cardiovascular inflammation but robust evidence is still lacking evidence is lacking. This article summarizes the current literature on cardiovascular and metabolic comorbidities in psoriasis, identifies research gaps, and suggests management strategies to reduce cardiovascular risk in patients with moderate to severe psoriasis. PMID:25412782

Ryan, Caitriona; Kirby, Brian

2015-01-01

103

Stress, depression, and cardiovascular dysregulation: A review of neurobiological mechanisms and the integration of research from preclinical disease models  

PubMed Central

A bidirectional association between mood disorders such as depression, and cardiovascular diseases such as myocardial infarction and congestive heart failure, has been described; however, the precise neurobiological mechanisms that underlie these associations have not been fully elucidated. This review is focused on the neurobiological processes and mediators that are common to both mood and cardiovascular disorders, with an emphasis on the role of exogenous stressors in addition to: (a) neuroendocrine and neurohumoral changes involving dysfunction of the hypothalamic-pituitary-adrenal axis and activation of the renin-angiotensin-aldosterone system, (b) immune alterations including activation of pro-inflammatory cytokines, (c) autonomic and cardiovascular dysregulation including increased sympathetic drive, withdrawal of parasympathetic tone, cardiac rate and rhythm disturbances, and altered baroreceptor reflex function, (d) central neurotransmitter system dysfunction including dopamine, norepinephrine and serotonin, and (e) behavioral changes including fatigue and physical inactivity. We also focus specifically on experimental investigations with preclinical disease models, conducted to elucidate the neurobiological mechanisms underlying the link between mood disorders and cardiovascular disease. These include: (a) the chronic mild stress model of depression, (b) a model of congestive heart failure, a model of cardiovascular deconditioning, (d) pharmacological manipulations of body fluid and sodium balance, and (e) pharmacological manipulations of the central serotonergic system. In combination with the extensive literature describing findings from human research, the investigation 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 better treatments and interventions for individuals with these co-morbid conditions. PMID:19116888

Grippo, Angela J.; Johnson, Alan Kim

2008-01-01

104

Management of cardiovascular complications in systemic lupus erythematosus  

PubMed Central

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Patients with SLE have an excess risk compared with the general population; this is particularly pronounced in younger women with SLE who have an excess risk of over 50-fold compared with population controls. There is a higher prevalence of subclinical atherosclerosis in patients with SLE compared with controls, as demonstrated by a variety of imaging modalities discussed in this review. The causality of the excess risk of CVD and subclinical atherosclerosis is multifactorial in patients with SLE. While traditional risk factors play a role, after controlling for the traditional Framingham risk factors, the excess risk is still 7.5-fold greater than the general population. This review will also cover novel cardiovascular risk factors and some SLE-specific variables that contribute to CVD risk. This review discusses the risk factor modification and the evidence available for treatment of these risk factors in SLE. There have not yet been any published randomized, controlled trials in patients with SLE with respect to CVD risk factor modifications. Thus, the treatment and management recommendations are based largely on published guidelines for other populations at high risk for CVD. PMID:20305727

Skamra, Carly; Ramsey-Goldman, Rosalind

2010-01-01

105

Neuropeptide control of the cardiovascular system in fish and reptiles.  

PubMed

Accumulating evidence shows the involvement of neuropeptides in cardiovascular control in mammals as well as non-mammalian species. Our own immunohistochemical studies indicate a sparse innervation only in cyclostomes, holostean fish and lungfish, a more extensive variation and distribution in elasmobranchs and teleosts, and a rich and varied innervation of the cardiovascular system in crocodiles and lizards. Vasoactive intestinal polypeptide (VIP), neuropeptie Y (NPY), gastrin releasing peptide (GRP) and tachykinins are present in most vertebrate groups. VIP is vasodilatory in the Atlantic cod (Gadus morhua) as in most mammalian species, but increases gut vascular resistance in the spiny dogfish (Squalus acanthias). NPY potentiates the effect of noradrenaline on skate (Raja rhina) coronary vessels, suggesting an interaction between adrenergic mechanisms and NPY early in evolution, but studies in the spiny dogfish and the crocodile also demonstrate different mechanisms for the action of NPY and adrenaline in some species. Bombesin/GRP increases flow to the gut in the spiny dogfish by an increase in somatic vascular resistance, while visceral resistance remains unchanged. In the caiman (Caiman crocodylus crocodylus) bombesin causes a shunting of blood from the lung to the gut. Substance P and other tachykinins in general increase flow to the gut, and on some occasions also increase somatic blood flow. Flow in the anastomosis of the crocodile (Crocodylus porosus) gut is increased by substance P. The results presented here are a review of several published and unpublished studies. PMID:8728849

Holmgren, S

1995-01-01

106

Prediction models for risk classification in cardiovascular disease.  

PubMed

Risk stratification is an increasingly important tool for the management of patients with different diseases and also for decision making in subjects not yet with overt disease but who are at risk of disease in the short or long term or during their lifetime. Careful risk assessment in the individual patient, based on clinical, laboratory and imaging data, can be helpful for making decisions about treatment or other prevention strategies. As regards cardiovascular disease, many models have been suggested and are available for the prediction of diagnosis and prognosis and there are several algorithms for risk prediction. However, current risk screening methods are not perfect. This review evaluates relative strengths and limitations of traditional and more recent methods for assessing the performance of prediction models. PMID:23053326

Petretta, Mario; Cuocolo, Alberto

2012-12-01

107

Role of cardiovascular imaging in systemic autoimmune diseases  

PubMed Central

Systemic autoimmune diseases are characterized by an excess of cardiovascular (CV) morbidity and mortality compared to the general population, mainly due to chronic inflammation that promotes the development of endothelial dysfunction and enhanced atherosclerosis. Early diagnosis of silent CV involvement is mandatory to improve the long term prognosis of these patients and CV imaging provides valuable information as a reliable diagnostic tool. Transthoracic echocardiography, with several applications (e.g. coronary flow reserve evaluation, tissue Doppler imaging, speckle tracking and the transesophageal approach), represents a first line evaluation, in association with biomarkers of endothelial dysfunction, such as asymmetric dimethylarginine. Nuclear medicine provides useful information on myocardial perfusion. The aim of this editorial is to provide a brief but complete review of the diagnostic tools available for screening and follow up of CV involvement in systemic autoimmune diseases. PMID:21160590

Sitia, Simona; Gianturco, Luigi; Tomasoni, Livio; Turiel, Maurizio

2010-01-01

108

Regulation of Chromatin Structure in the Cardiovascular System  

PubMed Central

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

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

2013-01-01

109

Use of implantable telemetry systems for study of cardiovascular phenomena.  

NASA Technical Reports Server (NTRS)

Preliminary observations of cardiovascular function have been made in four chimpanzees using multichannel implantable units. Measurements of right- and left-sided pressures were periodically made in these animals over a four-month period, including continuous observations for selected 24-hour periods. Pressures recorded with animals in an awake, unanesthetized, unrestrained state were much lower than pressures reported for restrained animals in similar situations. Diurnal variations of pressure tended to occur, but were not as clear-cut as those reported to occur for humans. The ability to implant a transmitter chronically and receive useful multichannel information in the chimpanzee encourages the future use of such implant devices as part of the control system for an artificial heart or directly for use in man.

Sandler, H.; Fryer, T. B.; Westbrook, R. M.; Stone, H. L.

1972-01-01

110

[Impact of aortic stiffness on central hemodynamics and cardiovascular system].  

PubMed

Arterial stiffness increases as a result of degenerative processes accelerated by aging and many risk factors, namely arterial hypertension. Basic clinical examination reveals increased pulse pressure as its hemodynamic manifestation. The most serious consequence of increased vascular stiffness, which cannot be revealed by clinical examination, is a change of central hemodynamics leading to increased load of left ventricle, left ventricular hypertrophy, diastolic dysfunction and to overall increase of cardiovascular risk. This review aimed to point at some patophysiological mechanisms taking part in the development of vascular stiffness, vascular remodeling and hemodynamic consequences of these changes. This work also gives an overview of noninvasive examination methods and their characteristics enabling to evaluate the local, regional and systemic arterial stiffness and central pulse wave analysis and their meaning for central hemodynamics and heart workload. PMID:23808736

Bulas, J; Poto?árová, M; Filková, M; Simková, A; Murín, J

2013-06-01

111

Weighted Hurdle Regression Method for Joint Modeling of Cardiovascular Events Likelihood and Rate in the U.S. Dialysis Population  

PubMed Central

SUMMARY We propose a new weighted hurdle regression method for modeling count data, with particular interest in modeling cardiovascular events in patients on dialysis. Cardiovascular disease remains one of the leading causes of hospitalization and death in this population. Our aim is to jointly model the relationship/association between covariates and (a) the probability of cardiovascular events, a binary process and (b) the rate of events once the realization is positive - when the ‘hurdle’ is crossed - using a zero-truncated Poisson distribution. When the observation period or follow-up time, from the start of dialysis, varies among individuals the estimated probability of positive cardiovascular events during the study period will be biased. Furthermore, when the model contains covariates, then the estimated relationship between the covariates and the probability of cardiovascular events will also be biased. These challenges are addressed with the proposed weighted hurdle regression method. Estimation for the weighted hurdle regression model is a weighted likelihood approach, where standard maximum likelihood estimation can be utilized. The method is illustrated with data from the United States Renal Data System. Simulation studies show the ability of proposed method to successfully adjust for differential follow-up times and incorporate the effects of covariates in the weighting. PMID:24930810

?entürk, Damla; Dalrymple, Lorien S.; Mu, Yi; Nguyen, Danh V.

2014-01-01

112

Influence of physical fields of active geological faults on the human cardiovascular system  

NASA Astrophysics Data System (ADS)

Results of studying the human cardiovascular system within zones of Altai Mountain geological faults are presented. It is shown that features of the geological-geophysical characteristics have an effect on different control circuits of the human cardiovascular system and cause a change in its functioning.

Shitov, A. V.; Borodin, A. S.; Tuzhilkin, D. A.; Apryatkina, M. L.

2014-12-01

113

Prediction and management of cardiovascular outcomes in systemic lupus erythematosus.  

PubMed

Atherosclerosis is the major cause of cardiovascular disease (CVD), which represents the major cause of death. During recent years, it has become clear that atherosclerosis is a chronic inflammatory condition where immunity could play an important role. Usually, it is when atherosclerotic plaques rupture that CVD follows, but some cases of CVD can occur without apparent atherosclerosis. In systemic lupus erythematosus, the risk of CVD is very high and the prevalence of atherosclerotic plaques, including vulnerable ones, is increased. A combination of traditional and non-traditional risk factors is implicated for the prediction of CVD in systemic lupus erythematosus. Traditional risk factors include hypertension, dyslipidemia, smoking and diabetes, though the exact importance of each of these in systemic lupus erythematosus is not clear. Anti-phospholipid antibodies, systemic inflammation and low levels of natural antibodies such as those against phosphorylcholine (anti-PC) are examples of non-traditional risk factors. Control of disease activity and disease manifestations and of established risk factors is important. PMID:25517760

Frostegĺrd, Johan

2015-02-01

114

Polymeric drug delivery systems for treatment of cardiovascular calcification, arrhythmias and restenosis  

Microsoft Academic Search

Cardiovascular controlled release, utilizing drug-polymer composites implanted in direct contact with the heart, has recently come into clinical use with a dexamethasone eluting cardiac pacemaker lead tip. Furthermore, cardiovascular controlled release systems are under active investigation in a number of other areas of possible application. The general working hypothesis of this approach is that regionally administered drug delivered directly to

Robert J. Levy; Vinod Labhasetwar; Cunxian Song; Eyal Lerner; Weiliam Chen; Narendra Vyavahare; Xuan Qu

1995-01-01

115

Effects of Tetrodotoxin on the Mammalian Cardiovascular System  

PubMed Central

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

Zimmer, Thomas

2010-01-01

116

A Simple Ballistocardiographic System for a Medical Cardiovascular Physiology Course  

NSDL National Science Digital Library

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 NewtonĂÂs 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.

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

2003-12-01

117

Computational models of cardiovascular response to orthostatic stress  

E-print Network

The cardiovascular response to changes in posture has been the focus of numerous investigations in the past. Yet despite considerable, targeted experimental effort, the mechanisms underlying orthostatic intolerance (OI) ...

Heldt, Thomas, 1972-

2004-01-01

118

Introduction: Cardiovascular physics  

NASA Astrophysics Data System (ADS)

The number of patients suffering from cardiovascular diseases increases unproportionally high with the increase of the human population and aging, leading to very high expenses in the public health system. Therefore, the challenge of cardiovascular physics is to develop high-sophisticated methods which are able to, on the one hand, supplement and replace expensive medical devices and, on the other hand, improve the medical diagnostics with decreasing the patient's risk. Cardiovascular physics-which interconnects medicine, physics, biology, engineering, and mathematics-is based on interdisciplinary collaboration of specialists from the above scientific fields and attempts to gain deeper insights into pathophysiology and treatment options. This paper summarizes advances in cardiovascular physics with emphasis on a workshop held in Bad Honnef, Germany, in May 2005. The meeting attracted an interdisciplinary audience and led to a number of papers covering the main research fields of cardiovascular physics, including data analysis, modeling, and medical application. The variety of problems addressed by this issue underlines the complexity of the cardiovascular system. It could be demonstrated in this Focus Issue, that data analyses and modeling methods from cardiovascular physics have the ability to lead to significant improvements in different medical fields. Consequently, this Focus Issue of Chaos is a status report that may invite all interested readers to join the community and find competent discussion and cooperation partners.

Wessel, Niels; Kurths, Jürgen; Ditto, William; Bauernschmitt, Robert

2007-03-01

119

Metal ions affecting the pulmonary and cardiovascular systems.  

PubMed

Some metals, such as copper and manganese, are essential to life and play irreplaceable roles in, e.g., the functioning of important enzyme systems. Other metals are xenobiotics, i.e., they have no useful role in human physiology and, even worse, as in the case of lead, may be toxic even at trace levels of exposure. Even those metals that are essential, however, have the potential to turn harmful at very high levels of exposure, a reflection of a very basic tenet of toxicology--"the dose makes the poison." Toxic metal exposure may lead to serious risks to human health. As a result of the extensive use of toxic metals and their compounds in industry and consumer products, these agents have been widely disseminated in the environment. Because metals are not biodegradable, they can persist in the environment and produce a variety of adverse effects. Exposure to metals can lead to damage in a variety of organ systems and, in some cases, metals also have the potential to be carcinogenic. Even though the importance of metals as environmental health hazards is now widely appreciated, the specific mechanisms by which metals produce their adverse effects have yet to be fully elucidated. The unifying factor in determining toxicity and carcinogenicity for most metals is the generation of reactive oxygen and nitrogen species. Metal-mediated formation of free radicals causes various modifications to nucleic acids, enhanced lipid peroxidation, and altered calcium and sulfhydryl homeostasis. Whilst copper, chromium, and cobalt undergo redox-cycling reactions, for metals such as cadmium and nickel the primary route for their toxicity is depletion of glutathione and bonding to sulfhydryl groups of proteins. This chapter attempts to show that the toxic effects of different metallic compounds may be manifested in the pulmonary and cardiovascular systems. The knowledge of health effects due to metal exposure is necessary for practising physicians, and should be assessed by inquiring about present and past occupational history and environmental exposure. PMID:21473377

Corradi, Massimo; Mutti, Antonio

2011-01-01

120

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

PubMed Central

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

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

2012-01-01

121

Pulmonary Complications Resulting from Genetic Cardiovascular Disease in Two Rat Models  

EPA Science Inventory

Underlying cardiovascular disease (CVD) has been considered a risk factor for exacerbation of air pollution health effects. Therefore, rodent models of CVD are increasingly used to examine mechanisms of variation in susceptibility. Pulmonary complications and altered iron homeost...

122

Pulmonary oxidative stress, inflammation and dysregulated iron homeostatis in rat models of cardiovascular disease  

EPA Science Inventory

Underlying cardiovascular disease (CVD) is considered a risk factor for the exacerbation of air pollution health effects. Therefore, rodent models of CVD are increasingly used to examine mechanisms ofvariation in susceptibility. Pulmonary oxidative stress, inflammation and altere...

123

Reduction of NADPH-oxidase activity ameliorates the cardiovascular phenotype in a mouse model of Williams-Beuren Syndrome.  

PubMed

A hallmark feature of Williams-Beuren Syndrome (WBS) is a generalized arteriopathy due to elastin deficiency, presenting as stenoses of medium and large arteries and leading to hypertension and other cardiovascular complications. Deletion of a functional NCF1 gene copy has been shown to protect a proportion of WBS patients against hypertension, likely through reduced NADPH-oxidase (NOX)-mediated oxidative stress. DD mice, carrying a 0.67 Mb heterozygous deletion including the Eln gene, presented with a generalized arteriopathy, hypertension, and cardiac hypertrophy, associated with elevated angiotensin II (angII), oxidative stress parameters, and Ncf1 expression. Genetic (by crossing with Ncf1 mutant) and/or pharmacological (with ang II type 1 receptor blocker, losartan, or NOX inhibitor apocynin) reduction of NOX activity controlled hormonal and biochemical parameters in DD mice, resulting in normalized blood pressure and improved cardiovascular histology. We provide strong evidence for implication of the redox system in the pathophysiology of the cardiovascular disease in a mouse model of WBS. The phenotype of these mice can be ameliorated by either genetic or pharmacological intervention reducing NOX activity, likely through reduced angII-mediated oxidative stress. Therefore, anti-NOX therapy merits evaluation to prevent the potentially serious cardiovascular complications of WBS, as well as in other cardiovascular disorders mediated by similar pathogenic mechanism. PMID:22319452

Campuzano, Victoria; Segura-Puimedon, Maria; Terrado, Verena; Sánchez-Rodríguez, Carolina; Coustets, Mathilde; Menacho-Márquez, Mauricio; Nevado, Julián; Bustelo, Xosé R; Francke, Uta; Pérez-Jurado, Luis A

2012-02-01

124

Regulation of NAD(P)H oxidases by AMPK in cardiovascular systems  

PubMed Central

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are ubiquitously produced in cardiovascular systems. Under physiological conditions, ROS/RNS function as signaling molecules that are essential in maintaining cardiovascular function. Aberrant concentrations of ROS/RNS have been demonstrated in cardiovascular diseases due to increased production or decreased scavenging, which have been considered as common pathways for the initiation and progression of cardiovascular diseases such as atherosclerosis, hypertension, (re)stenosis, and congestive heart failure. NAD(P)H oxidases are primary sources of ROS and can be induced or activated by all known cardiovascular risk factors. Stresses, hormones, vasoactive agents, and cytokines via different signaling cascades control the expression and activity of these enzymes and of their regulatory subunits. But the molecular mechanisms by which NAD(P)H oxidase is regulated in cardiovascular systems remain poorly characterized. Investigations by us and others suggest that adenosine monophosphate-activated protein kinase (AMPK), as an energy sensor and modulator, is highly sensitive to ROS/RNS. We have also obtained convincing evidence that AMPK is a physiological suppressor of NAD(P)H oxidase in multiple cardiovascular cell systems. In this review, we summarize our current understanding of how AMPK functions as a physiological repressor of NAD(P)H oxidase. PMID:22357101

Song, Ping; Zou, Ming-Hui

2012-01-01

125

Oxidative stress-mediated effects of angiotensin II in the cardiovascular system  

PubMed Central

Angiotensin II (Ang II), an endogenous peptide hormone, plays critical roles in the pathophysiological modulation of cardiovascular functions. Ang II is the principle effector of the renin-angiotensin system for maintaining homeostasis in the cardiovascular system, as well as a potent stimulator of NAD(P)H oxidase, which is the major source and primary trigger for reactive oxygen species (ROS) generation in various tissues. Recent accumulating evidence has demonstrated the importance of oxidative stress in Ang II-induced heart diseases. Here, we review the recent progress in the study on oxidative stress-mediated effects of Ang II in the cardiovascular system. In particular, the involvement of Ang II-induced ROS generation in arrhythmias, cell death/heart failure, ischemia/reperfusion injury, cardiac hypertrophy and hypertension are discussed. Ca2+/calmodulin-dependent protein kinase II is an important molecule linking Ang II, ROS and cardiovascular pathological conditions. PMID:24587981

Wen, Hairuo; Gwathmey, Judith K; Xie, Lai-Hua

2014-01-01

126

AptaCDSS-E: A classifier ensemble-based clinical decision support system for cardiovascular disease level prediction  

E-print Network

AptaCDSS-E: A classifier ensemble-based clinical decision support system for cardiovascular disease); Cardiovascular disease; Classifier ensemble; Support vector machines; Neural networks; Decision trees; Bayesian that cardiovascular disease (CVD), which includes heart disease and stroke, is one of the lead- ing causes of death

127

Angiotensin II type-2 receptor-specific effects on the cardiovascular system  

PubMed Central

The renin-angiotensin system (RAS) is intricately involved in cardiovascular homeostasis. It is well known that angiotensin II, the key effector in RAS, contributes to a range of cardiovascular pathologies and diseases via angiotensin II type-1 receptor (AT1R) activation. However, the role of angiotensin II type-2 receptor (AT2R) regulation is less well understood. Recent studies describe the role of the AT2R on cardiovascular function in normal and pathologic conditions. The data describe an important role of AT2R in blood pressure regulation, cardiac hypertrophy and fibrosis, myocardial infarction and vascular homeostasis. PMID:24282697

Li, Ying; Li, Xiao-hui

2012-01-01

128

A common data model to assess cardiovascular hospitalization and mortality in atrial fibrillation patients using administrative claims and medical records  

PubMed Central

Purpose Atrial fibrillation/flutter (AF) is frequently associated with cardiovascular comorbidities. Observational health care databases are commonly used for research purposes in studies of quality of care, health economics, outcomes research, drug safety, and epidemiology. This retrospective cohort study applied a common data model to administrative claims data (Truven Health Analytics MarketScan® claims databases [MS-Claims]) and electronic medical records data (Geisinger Health System’s MedMining electronic medical record database [MG-EMR]) to examine the risk of cardiovascular hospitalization and all-cause mortality in relation to clinical risk factors in recent-onset AF and to assess the consistency of analyses for each data source. Methods Cohorts of patients with newly diagnosed AF (n=105,262 [MS-Claims] and n=3,919 [MG-EMR]) and demographically similar patients without AF (n=105,262 [MS-Claims] and n=3,872 [MG-EMR]) were followed from the qualifying AF diagnosis until cardiovascular hospitalization, death, database disenrollment, or study completion. A common data model standardized the data in structure, format, content, and nomenclature to allow for systematic assessment and comparison of outcomes from two disparate data sets. Results In both databases, AF patients had greater overall baseline comorbidity and higher incidence rates of cardiovascular hospitalization (threefold higher) and all-cause mortality (46% higher) than non-AF patients. For AF patients, incidence rates of cardiovascular hospitalization and all-cause mortality were increased by the concomitant presence of coronary disease, chronic obstructive pulmonary disease, and stroke at baseline. Overall, the pattern of cardiovascular hospitalization in the MS-Claims database was similar to that in the MG-EMR database. Compared with the MS-Claims database, the use of cardiovascular medications and the capture of certain comorbidities among AF patients appeared to be higher in the MG-EMR data set. Conclusion Similar standardized analyses across EMR and Claims databases were consistent in the association of AF with acute morbidity and an increased risk of all-cause mortality. Areas of inconsistency were due to differences in underlying population demographics and cardiovascular risks and completeness of certain data fields.

Panaccio, Mary P; Cummins, Gordon; Wentworth, Charles; Lanes, Stephan; Reynolds, Shannon L; Reynolds, Matthew W; Miao, Raymond; Koren, Andrew

2015-01-01

129

Role of the kallikrein-kinin system in the maturation of cardiovascular phenotype.  

PubMed

Recent studies indicate that during early phases of life the kallikrein-kinin system (KKS) plays a role in kidney development. In the rat kidney, the spatial and temporal pattern of expression of the genes encoding for kallikrein or bradykinin (BK) B2-receptors parallels postnatal nephrogenesis and blood flow redistribution from the inner to the outer renal cortex. Animal models with genetic dysfunction of the renal KKS show alterations in the functional maturation of the kidney, and ultimately develop salt-sensitive hypertension. Kininogen-deficient Brown Norway Katholiek rats have undetectable urinary kinin levels and show an exaggerated blood pressure sensitivity to chronic excess of salt or mineralocorticoids. Another rat model with genetic reduction in urinary kallikrein excretion is characterized by an altered pressure-natriuresis relationship, with this defect being corrected by infusion of purified rat tissue kallikrein. Knockout mice lacking the BK B2-receptor gene show elevated blood pressure and heart rate under basal conditions and enhanced blood pressure sensitivity to salt. In rats, prenatal blockade of the BK B2-receptor by icatibant leads to a cardiovascular phenotype similar to that of animals with genetic defects of the KKS. Delayed renal maturation is observed when high salt intake is associated with icatibant. Collectively, these findings indicate a relevant role of the KKS in the physiologic maturation of renal and cardiovascular phenotypes. Genetic or environmental factors, able to potentiate the activity of the renal KKS, could protect against the development of arterial hypertension. PMID:10560785

Emanueli, C; Madeddu, P

1999-10-01

130

Modelling study of the acute cardiovascular response to hypocapnic hypoxia in healthy and anaemic subjects  

Microsoft Academic Search

The present study analyses the cardiovascular response to acute hypocapnic hypoxia (simulating the effect of respiration at\\u000a high altitude) both in healthy, unacclimatised subjects and in subjects with moderate anaemia, by means of a mathematical\\u000a model of short-term cardiovascular regulation. During severe hypoxia, cardiac output and heart rate (HR) exhibit a significant\\u000a increase compared with the basal level (cardiac output:

E. Magosso; M. Ursino

2004-01-01

131

Comparison between recombinant baculo- and adenoviral-vectors as transfer system in cardiovascular cells  

Microsoft Academic Search

Summary.  The development of effective gene-therapeutic applications for cardiovascular disorders is in part limited by the lack of\\u000a appropriate delivery systems. In an attempt to overcome this deficiency, we investigated the ability of baculoviral vectors\\u000a to transduce human cardiovascular cells, for which data are missing in literature. Additionally, baculovirus ability to transduce\\u000a target cells was compared to that of an adenoviral

G. Grassi; H. Köhn; B. Dapas; R. Farra; J. Platz; S. Engel; S. Cjsareck; R. Kandolf; C. Teutsch; R. Klima; G. Triolo; A. Kuhn

2006-01-01

132

Menstrual Cycle Effects on the Neurohumoral and Autonomic Nervous Systems Regulating the Cardiovascular System  

Microsoft Academic Search

Gonadal hormones may affect homeostatic mechanisms reg- ulating the cardiovascular system. We investigated this rela- tionship at five different crucial hormonal time points along the menstrual cycle. Eight eumenorrheic healthy subjects underwent a battery of autonomic tests, hemodynamics, and volume-regulatory hormone measurements. Fluid-regulatory hormones, plasma renin activity, and aldosterone increased along the luteal phase (P 0.003 and 0.02, respectively), whereas

NIR HIRSHOREN; INNA TZORAN; IGOR MAKRIENKO; YEHUDA EDOUTE; MIKAHL M. PLAWNER; JOSEPH ITSKOVITZ-ELDOR; GIRIS JACOB

133

Autonomic Nervous System Dysfunction and Inflammation Contribute to the Increased Cardiovascular Mortality Risk Associated With Depression  

PubMed Central

Objective To investigate prospectively whether autonomic nervous system (ANS) dysfunction and inflammation play a role in the increased cardiovascular disease (CVD)-related mortality risk associated with depression. Methods Participants in the Cardiovascular Health Study (n = 907; mean age, 71.3 ± 4.6 years; 59.1% women) were evaluated for ANS indices derived from heart rate variability (HRV) analysis (frequency and time domain HRV, and nonlinear indices, including detrended fluctuation analysis (DFA1) and heart rate turbulence). Inflammation markers included C-reactive protein, interleukin-6, fibrinogen, and white blood cell count). Depressive symptoms were assessed, using the 10-item Centers for Epidemiological Studies Depression scale. Cox proportional hazards models were used to investigate the mortality risk associated with depression, ANS, and inflammation markers, adjusting for demographic and clinical covariates. Results Depression was associated with ANS dysfunction (DFA1, p = .018), and increased inflammation markers (white blood cell count, p = .012, fibrinogen p = .043) adjusting for covariates. CVD-related mortality occurred in 121 participants during a median follow-up of 13.3 years. Depression was associated with an increased CVD mortality risk (hazard ratio, 1.88; 95% confidence interval, 1.23–2.86). Multivariable analyses showed that depression was an independent predictor of CVD mortality (hazard ratio, 1.72; 95% confidence interval, 1.05–2.83) when adjusting for independent HRV and inflammation predictors (DFA1, heart rate turbulence, interleukin-6), attenuating the depression-CVD mortality association by 12.7% (p < .001). Conclusion Autonomic dysfunction and inflammation contribute to the increased cardiovascular mortality risk associated with depression, but a large portion of the predictive value of depression remains unexplained by these neuroimmunological measures. PMID:20639389

Kop, Willem J.; Stein, Phyllis K.; Tracy, Russell P.; Barzilay, Joshua I.; Schulz, Richard; Gottdiener, John S.

2011-01-01

134

Thiazolidinediones: effects on insulin resistance and the cardiovascular system  

PubMed Central

Thiazolidinediones (TZDs) have been used for the treatment of hyperglycaemia in type 2 diabetes for the past 10 years. They may delay the development of type 2 diabetes in individuals at high risk of developing the condition, and have been shown to have potentially beneficial effects on cardiovascular risk factors. TZDs act as agonists of peroxisome proliferator-activated receptor-? (PPAR-?) primarily in adipose tissue. PPAR-? receptor activation by TZDs improves insulin sensitivity by promoting fatty acid uptake into adipose tissue, increasing production of adiponectin and reducing levels of inflammatory mediators such as tumour necrosis factor-alpha (TNF-?), plasminogen activator inhibitor-1(PAI-1) and interleukin-6 (IL-6). Clinically, TZDs have been shown to reduce measures of atherosclerosis such as carotid intima-media thickness (CIMT). However, in spite of beneficial effects on markers of cardiovascular risk, TZDs have not been definitively shown to reduce cardiovascular events in patients, and the safety of rosiglitazone in this respect has recently been called into question. Dual PPAR-?/? agonists may offer superior treatment of insulin resistance and cardioprotection, but their safety has not yet been assured. PMID:17906687

Quinn, C E; Hamilton, P K; Lockhart, C J; McVeigh, G E

2007-01-01

135

Echocardiographic characterization of the cardiovascular phenotype in rodent models.  

PubMed

Echocardiographic techniques are commonly utilized to describe the rodent cardiovascular phenotype. These approaches are contrasted with other in vivo methods and are positioned in the assay selection process by a review of studies from our laboratory and others. Although not conventionally considered a biomarker, the technique has the potential to be exploited as a marker of intentional or unanticipated toxic biological effects in the preclinical development of drugs and chemicals. PMID:16507551

Hoit, Brian D

2006-01-01

136

Physiological interdependence of the cardiovascular and postural control systems under orthostatic stress.  

PubMed

The cardiovascular system has been observed to respond to changes in human posture and the environment. On the same lines, frequent fallers have been observed to suffer from cardiovascular deficits. The present article aims to demonstrate the existence of interactions between the cardiovascular and postural control systems. The behavior of the two systems under orthostatic challenge was studied through novel adaptations of signal processing techniques. To this effect, the interactions between the two systems were assessed with two metrics, coherence and phase lock value, based on the wavelet transform. Measurements from the cardiovascular system (blood pressure), lower limb muscles (surface electromyography), and postural sway (center of pressure) were acquired from young healthy adults (n = 28, men = 12, age = 20-28 yr) during quiet stance. The continuous wavelet transform was applied to decompose the representative signals on a time-scale basis in a frequency region of 0.01 to 0.1 Hz. Their linear coupling was quantified through a coherence metric, and the synchrony was characterized via the phase information. The outcomes of this study present evidence that the cardiovascular and postural control systems work together to maintain homeostasis under orthostatic challenge. The inferences open a new direction of study for effects under abnormalities and extreme environmental conditions. PMID:24858845

Garg, Amanmeet; Xu, Da; Laurin, Alexandre; Blaber, Andrew P

2014-07-15

137

Cardiovascular physiology in space flight  

NASA Technical Reports Server (NTRS)

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.

Charles, John B.; Bungo, Michael W.

1991-01-01

138

Adrenoreceptors and nitric oxide in the cardiovascular system  

PubMed Central

Nitric Oxide (NO) is a small molecule that continues to attract much attention from the scientific community. Since its discovery, it has been evident that NO has a crucial role in the modulation of vascular tone. Moreover, NO is involved in multiple signal transduction pathways thus contributing to the regulation of many cellular functions. NO effects can be either dependent or independent on cGMP, and rely also upon several mechanisms such as the amount of NO, the compartmentalization of the enzymes responsible for its biosynthesis (NOS), and the local redox conditions. Several evidences highlighted the correlation among adrenoreceptors activity, vascular redox status and NO bioavailability. It was suggested a possible crosstalk between NO and oxidative stress hallmarks in the endothelium function and adaptation, and in sympathetic vasoconstriction control. Adrenergic vasoconstriction is a balance between a direct vasoconstrictive effect on smooth muscle and an indirect vasorelaxant action caused by ?2- and ?-adrenergic endothelial receptor-triggered NO release. An increased oxidative stress and a reduction of NO bioavailability shifts this equilibrium causing the enhanced vascular adrenergic responsiveness observed in hypertension. The activity of NOS contributes to manage the adrenergic pathway, thus supporting the idea that the endothelium might control or facilitate ?-adrenergic effects on the vessels and the polymorphic variants in ?2-receptors and NOS isoforms could influence aging, some pathological conditions and individual responses to drugs. This seems to be dependent, almost in part, on differences in the control of vascular tone exerted by NO. Given its involvement in such important mechanisms, the NO pathway is implicated in aging process and in both cardiovascular and non-cardiovascular conditions. Thus, it is essential to pinpoint NO involvement in the regulation of vascular tone for the effective clinical/therapeutic management of cardiovascular diseases (CVD). PMID:24223559

Conti, Valeria; Russomanno, Giusy; Corbi, Graziamaria; Izzo, Viviana; Vecchione, Carmine; Filippelli, Amelia

2013-01-01

139

2006-1968: TEACHING BASIC CARDIO-VASCULAR MECHANICS WITH LEGO MODELS: A HIGH SCHOOL CASE STUDY  

E-print Network

of the cardio-vascular system through fluid mechanics. It will explore the human circulatory system, while in Mathematics from the Urals State University and the Ph.D. in computer aided design systems in manufacturing involving the concept of pressure. Students will explore the cardio-vascular system through both computer

140

Mechanisms underlying altered mood and cardiovascular dysfunction: the value of neurobiological and behavioral research with animal models.  

PubMed

A bidirectional association between mood disorders and cardiovascular diseases has been described in humans, yet the precise neurobiological mechanisms that underlie this association are not fully understood. This article is focused on neurobiological processes and mediators in mood and cardiovascular disorders, with an emphasis on common mechanisms including stressor reactivity, neuroendocrine and neurohumoral changes, immune alterations, autonomic and cardiovascular dysregulation, and central neurotransmitter and neuropeptide dysfunction. A discussion of the utility of experimental investigations with rodent models, including those in rats and prairie voles (Microtus ochrogaster), is presented. Specific studies using these models are reviewed, focusing on the analysis of behavioral, physiological and neural mechanisms underlying depressive disorders and cardiovascular disease. Considered in combination with studies using human samples, the investigation of mechanisms underlying depressive behaviors and cardiovascular regulation using animal models will enhance our understanding of the association of depression and cardiovascular disease, and will promote the development of improved interventions for individuals with these detrimental disorders. PMID:18703084

Grippo, Angela J

2009-02-01

141

Imaging the small animal cardiovascular system in real-time with multispectral optoacoustic tomography  

NASA Astrophysics Data System (ADS)

Multispectral Optoacoustic Tomography (MSOT) is an emerging technique for high resolution macroscopic imaging with optical and molecular contrast. We present cardiovascular imaging results from a multi-element real-time MSOT system recently developed for studies on small animals. Anatomical features relevant to cardiovascular disease, such as the carotid arteries, the aorta and the heart, are imaged in mice. The system's fast acquisition time, in tens of microseconds, allows images free of motion artifacts from heartbeat and respiration. Additionally, we present in-vivo detection of optical imaging agents, gold nanorods, at high spatial and temporal resolution, paving the way for molecular imaging applications.

Taruttis, Adrian; Herzog, Eva; Razansky, Daniel; Ntziachristos, Vasilis

2011-03-01

142

Modeling cardiovascular hemodynamics using the lattice Boltzmann method on massively parallel supercomputers  

NASA Astrophysics Data System (ADS)

Accurate and reliable modeling of cardiovascular hemodynamics has the potential to improve understanding of the localization and progression of heart diseases, which are currently the most common cause of death in Western countries. However, building a detailed, realistic model of human blood flow is a formidable mathematical and computational challenge. The simulation must combine the motion of the fluid, the intricate geometry of the blood vessels, continual changes in flow and pressure driven by the heartbeat, and the behavior of suspended bodies such as red blood cells. Such simulations can provide insight into factors like endothelial shear stress that act as triggers for the complex biomechanical events that can lead to atherosclerotic pathologies. Currently, it is not possible to measure endothelial shear stress in vivo, making these simulations a crucial component to understanding and potentially predicting the progression of cardiovascular disease. In this thesis, an approach for efficiently modeling the fluid movement coupled to the cell dynamics in real-patient geometries while accounting for the additional force from the expansion and contraction of the heart will be presented and examined. First, a novel method to couple a mesoscopic lattice Boltzmann fluid model to the microscopic molecular dynamics model of cell movement is elucidated. A treatment of red blood cells as extended structures, a method to handle highly irregular geometries through topology driven graph partitioning, and an efficient molecular dynamics load balancing scheme are introduced. These result in a large-scale simulation of the cardiovascular system, with a realistic description of the complex human arterial geometry, from centimeters down to the spatial resolution of red-blood cells. The computational methods developed to enable scaling of the application to 294,912 processors are discussed, thus empowering the simulation of a full heartbeat. Second, further extensions to enable the modeling of fluids in vessels with smaller diameters and a method for introducing the deformational forces exerted on the arterial flows from the movement of the heart by borrowing concepts from cosmodynamics are presented. These additional forces have a great impact on the endothelial shear stress. Third, the fluid model is extended to not only recover Navier-Stokes hydrodynamics, but also a wider range of Knudsen numbers, which is especially important in micro- and nano-scale flows. The tradeoffs of many optimizations methods such as the use of deep halo level ghost cells that, alongside hybrid programming models, reduce the impact of such higher-order models and enable efficient modeling of extreme regimes of computational fluid dynamics are discussed. Fourth, the extension of these models to other research questions like clogging in microfluidic devices and determining the severity of co-arctation of the aorta is presented. Through this work, a validation of these methods by taking real patient data and the measured pressure value before the narrowing of the aorta and predicting the pressure drop across the co-arctation is shown. Comparison with the measured pressure drop in vivo highlights the accuracy and potential impact of such patient specific simulations. Finally, a method to enable the simulation of longer trajectories in time by discretizing both spatially and temporally is presented. In this method, a serial coarse iterator is used to initialize data at discrete time steps for a fine model that runs in parallel. This coarse solver is based on a larger time step and typically a coarser discretization in space. Iterative refinement enables the compute-intensive fine iterator to be modeled with temporal parallelization. The algorithm consists of a series of prediction-corrector iterations completing when the results have converged within a certain tolerance. Combined, these developments allow large fluid models to be simulated for longer time durations than previously possible.

Randles, Amanda Elizabeth

143

Predictors of the first cardiovascular event in patients with systemic lupus erythematosus - a prospective cohort study  

PubMed Central

Introduction Cardiovascular disease (CVD) is a major cause of premature mortality among Systemic lupus erythematosus (SLE) patients. Many studies have measured and evaluated risk factors for premature subclinical atherosclerosis, but few studies are prospective and few have evaluated risk factors for hard endpoints, i.e. clinically important cardiovascular events (CVE). We investigated the impact of traditional and lupus associated risk factors for the first ever CVE in a longitudinal cohort of SLE patients. Methods A total of 182 SLE patients (mean age 43.9 years) selected to be free of CVE were included. Cardiovascular and autoimmune biomarkers were measured on samples collected after overnight fasting at baseline. Clinical information was collected at baseline and at follow up. End point was the first ever CVE (ischemic heart, cerebrovascular or peripheral vascular disease or death due to CVD). Impact of baseline characteristics/biomarkers on the risk of having a first CVE was evaluated with Cox regression. Results Follow up was 99.5% after a mean time of 8.3 years. Twenty-four patients (13%) had a first CVE. In age-adjusted Cox regression, any positive antiphospholipid antibody (aPL), elevated markers of endothelial activation (von Willebrand factor (vWf), soluble vascular cellular adhesion molecule-1 (sVCAM-1)) and fibrinogen predicted CVEs. Of SLE manifestations, arthritis, pleuritis and previous venous occlusion were positively associated with future CVEs while thrombocytopenia was negatively associated. Among traditional risk factors only age and smoking were significant predictors. In a multivariable Cox regression model age, any positive aPL, vWf and absence of thrombocytopenia were all predictors of the first CVE. Conclusions In addition to age, positive aPL, biomarkers indicating increased endothelial cell activity/damage, and absence of thrombocytopenia were independent predictors of CVEs in this prospective study. Our results indicate that activation of the endothelium and the coagulation system are important features in SLE related CVD. Furthermore, we observed that the risk of CVEs seems to differ between subgroups of SLE patients. PMID:20003285

2009-01-01

144

Implementation strategies of Systems Medicine in clinical research and home care for cardiovascular disease patients.  

PubMed

Insights from the "-omics" science have recently emphasized the need to implement an overall strategy in medical research. Here, the development of Systems Medicine has been indicated as a potential tool for clinical translation of basic research discoveries. Systems Medicine also gives the opportunity of improving different steps in medical practice, from diagnosis to healthcare management, including clinical research. The development of Systems Medicine is still hampered however by several challenges, the main one being the development of computational tools adequate to record, analyze and share a large amount of disparate data. In addition, available informatics tools appear not yet fully suitable for the challenge because they are not standardized, not universally available, or with ethical/legal concerns. Cardiovascular diseases (CVD) are a very promising area for translating Systems Medicine into clinical practice. By developing clinically applied technologies, the collection and analysis of data may improve CV risk stratification and prediction. Standardized models for data recording and analysis can also greatly broaden data exchange, thus promoting a uniform management of CVD patients also useful for clinical research. This advance however requires a great organizational effort by both physicians and health institutions, as well as the overcoming of ethical problems. This narrative review aims at providing an update on the state-of-art knowledge in the area of Systems Medicine as applied to CVD, focusing on current critical issues, providing a road map for its practical implementation. PMID:25283057

Montecucco, Fabrizio; Carbone, Federico; Dini, Frank Lloyd; Fiuza, Manuela; Pinto, Fausto J; Martelli, Antonietta; Palombo, Domenico; Sambuceti, Gianmario; Mach, François; De Caterina, Raffaele

2014-11-01

145

Interactions between immune, stress-related hormonal and cardiovascular systems following strenuous physical exercise.  

PubMed

Physical exercise represents a eustress condition that promotes rapid coordinated adjustments in the immune, stress-related hormonal and cardiovascular systems, for maintaining homeostasis in response to increased metabolic demands. Compared to the tight multisystem coordination during exercise, evidence of between-systems cross talk in the early post exercise is still lacking. This study was aimed at identifying possible interactions between multiple systems following strenuous physical exercise (Ironman race) performed by twenty well-trained triathletes. Cardiac hemodynamics, left ventricle systolic and diastolic function and heart rate variability were measured along with plasma concentrations of immune messengers (cytokines and C-reactive protein) and stress-related hormones (catecholamines and cortisol) both 24h before and within 20 min after the race. Observed changes in antiinflammatory pathways, stress-related hormones and cardiovascular function were in line with previous findings; moreover, correlating parameters' changes (post versus pre-race) highlighted a dependence of cardiovascular function on the post-race biohumoral milieu: in particular, individual post-race variations of heart rate and diastolic function were strongly correlated with individual variations of anti-inflammatory cytokines, while individual baroreflex sensitivity changes were linked to IL-8 increase. Multiple correlations between anti-inflammatory cytokines and catecholamines were also found according with the autonomic regulation of immune function. Observed post-race cytokine and hormone levels were presumptively representative of the increases reached at the effort end while the cardiovascular parameters after the race were measured during the cardiovascular recovery; thus, results suggest that sustained strenuous exercise produced a stereotyped cardiovascular early recovery, whose speed could be conditioned by the immune and stress-related hormonal milieu. PMID:24599630

Menicucci, Danilo; Piarulli, Andrea; Mastorci, Francesca; Sebastiani, Laura; Laurino, Marco; Garbella, Erika; Castagnini, Cinzia; Pellegrini, Silvia; Lubrano, Valter; Bernardi, Giulio; Metelli, Maria; Bedini, Remo; L'abbate, Antonio; Pingitore, Alessandro; Gemignani, Angelo

2013-09-01

146

Matching index of refraction using a diethyl phthalate\\/ethanol solution for in vitro cardiovascular models  

Microsoft Academic Search

Experiments studying cardiovascular geometries require a working fluid that matches the high index of refraction of glass and silicone, has a low viscosity, and is safe and inexpensive. A good candidate working fluid is diethyl phthalate (DEP), diluted with ethanol. Measurements were made of index of refraction and viscosity of varied dilutions at a range of temperatures, and empirical models

P. Miller; K. Danielson; G. Moody; A. Slifka; E. Drexler; J. Hertzberg

2006-01-01

147

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

Microsoft Academic Search

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

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

1999-01-01

148

Elucidation of Cardiovascular System Pathology Using Pulse Wave Phase Space Analysis  

Microsoft Academic Search

Human body pathology and normal states are docu? mented by the World Health Organization. Strict mathe? matical equations and language substitute descriptive and qualitative terms. The goal of this work was to provide express diagno? sis based on twodimensional analysis of cardiovascular system pathology using pulse wave phase space analysis in sphygmography. N. A. Amosov studied contractile myocardium function in

V. I. Volkov; S. A. Ostanin; S. V. Zasorin; V. P. Kulikov

2009-01-01

149

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...

150

Protective actions of melatonin and growth hormone on the aged cardiovascular system.  

PubMed

Abstract Epidemiological studies indicate that certain aspects of lifestyle and genetics act as risk factors for a variety of cardiovascular disorders, including coronary disease, hypertension, heart failure and stroke. Aging, however, appears to be the major contributor for morbidity and mortality of the impaired cardiovascular system. Growth hormone (GH) and melatonin seem to prevent cardiac aging, as they contribute to the recovery of several physiological parameters affected by age. These hormones exhibit antioxidant properties and decrease oxidative stress and apoptosis. This paper summarizes a set of studies related to the potential role that therapy with GH and melatonin may play in the protection of the altered cardiac function due to aging, with a focus on experiments performed in our laboratory using the senescence-accelerated mouse as an aging model. In general, we observed significantly increased inflammation, oxidative stress and apoptosis markers in hearts from senescence-accelerated prone 10-month-old animals compared to 2-month-old controls, while anti-inflammatory and antiapoptotic markers as well as endothelial nitric oxide synthase were decreased. Senescence-accelerated resistant animals showed no significant changes with age. GH or melatonin treatment prevented the age-dependent cardiac alterations observed in the senescence-accelerated prone group. Combined administration of GH plus melatonin reduced the age-related changes in senescence-accelerated prone hearts in an additive fashion that was different to that displayed when administered alone. GH and melatonin may be potential agents for counteracting oxidative stress, apoptosis and inflammation in the aging heart. PMID:25390004

Paredes, Sergio D; Forman, Katherine A; García, Cruz; Vara, Elena; Escames, Germaine; Tresguerres, Jesús A F

2014-05-01

151

Postdoctoral Fellow Neural Cardiovascular Physiology  

E-print Network

Postdoctoral Fellow Neural Cardiovascular Physiology Job Description A postdoctoral position is available at Colorado State University, Department of Biomedical Sciences; Center for Cardiovascular and physiological roles of new components of the renin-angiotensin system in the regulation of cardiovascular

Collett Jr., Jeffrey L.

152

The relationship between subtypes of depression and cardiovascular disease: a systematic review of biological models.  

PubMed

A compelling association has been observed between cardiovascular disease (CVD) and depression, suggesting individuals with depression to be at significantly higher risk for CVD and CVD-related mortality. Systemic immune activation, hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, arterial stiffness and endothelial dysfunction have been frequently implicated in this relationship. Although a differential epidemiological association between CVD and depression subtypes is evident, it has not been determined if this indicates subtype specific biological mechanisms. A comprehensive systematic literature search was conducted using PubMed and PsycINFO databases yielding 147 articles for this review. A complex pattern of systemic immune activation, endothelial dysfunction and HPA axis hyperactivity is suggestive of the biological relationship between CVD and depression subtypes. The findings of this review suggest that diagnostic subtypes rather than a unifying model of depression should be considered when investigating the bidirectional biological relationship between CVD and depression. The suggested model of a subtype-specific biological relationship between depression and CVDs has implications for future research and possibly for diagnostic and therapeutic processes. PMID:22832857

Baune, B T; Stuart, M; Gilmour, A; Wersching, H; Heindel, W; Arolt, V; Berger, K

2012-01-01

153

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

PubMed

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?ą) 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?ą), 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

Joyce, William; Wang, Tobias

2014-08-01

154

Central Nervous System Serotonin and Clustering of Hostility, Psychosocial, Metabolic and Cardiovascular Endophenotypes in Men  

PubMed Central

Objective To use measures of CSF 5HIAA and MAOA-uVNTR genotype to study the role of central nervous system (CNS) serotonin in clustering of hostility, and other psychosocial, metabolic and cardiovascular endophenotypes. Methods In 86 healthy men, we evaluated cerebrospinal fluid (CSF) levels of the primary serotonin metabolite 5-hydroxyindoleacetic acid (5HIAA) and genotype on a functional promoter polymorphism of the monoamine oxidase A gene (M-uVNTR) for association with 29 variables assessing hostility, other psychosocial, metabolic, neuroendocrine and cardiovascular endophenotypes. Results The correlations of 5HIAA with these endophenotypes in men with more active MAOA-uVNTR alleles were significantly different from those with less active alleles for 15 of 29 endophenotypes. MAOA-uVNTR phenotype and CSF 5HIAA interacted to explain 20% and 22% of the variance, respectively, in scores on one factor wherein high scores reflected a less healthy psychosocial profile and a second factor wherein high score reflected increased insulin resistance, BMI, blood pressure and hostility. In men with less active alleles, higher 5HIAA was associated with more favorable profiles of hostility, other psychosocial, metabolic and cardiovascular endophenotypes; in men with more active alleles, higher 5HIAA was associated with less favorable profiles. Conclusions These findings indicate that in men indices of CNS serotonin function influence the expression and clustering of hostility, other psychosocial, metabolic and cardiovascular endophenotypes that have been shown to increase risk of developing cardiovascular disease. The findings are consistent with the hypothesis that increased CNS serotonin is associated with a more favorable psychosocial/metabolic/cardiovascular profile, while decreased CNS serotonin function is associated with a less favorable profile. PMID:20595415

Williams, Redford B.; Surwit, Richard S.; Siegler, Ilene C.; Ashley-Koch, Allison E.; Collins, Ann L.; Helms, Michael J.; Georiades, Anastasia; Boyle, Stephen H.; Brummett, Beverly H.; Barefoot, John C.; Grichnik, Katherine; Stafford-Smith, Mark; Kuhn, Cynthia M.

2013-01-01

155

Telomere biology in cardiovascular disease: the TERC-/- mouse as a model for heart failure and ageing.  

PubMed

Atherosclerosis and heart failure are major causes of morbidity and mortality in Western countries. Recent studies are suggesting involvement of telomere biology in the development and progression of age-associated conditions, including hypertension, atherosclerosis, and heart failure. Whether any of these reported associations are based on causal relationships remains to be elucidated. The construction of telomerase-deficient (telomerase RNA component, TERC(-/-)) mice might provide a potential instrumental model to study the involvement of telomere biology in cardiovascular disease. Here, we review the current available information from all studies performed in TERC(-/-) mice providing information on the cardiovascular phenotypic characteristics. Although this mouse model has proven its value in the understanding of the role of telomere biology in cancer, stem cell, and basic telomere research, only few studies were specifically designed to answer cardiovascular-related questions. The TERC(-/-) mice provide exciting opportunities to expand our knowledge of telomere biology in cardiovascular disease and the potential identification of novel targets of treatment. PMID:19047341

Wong, Liza S M; Oeseburg, Hisko; de Boer, Rudolf A; van Gilst, Wiek H; van Veldhuisen, Dirk J; van der Harst, Pim

2009-02-01

156

Space Weather and a State of Cardiovascular System of Human Being with a Weakened Adaptation System  

NASA Astrophysics Data System (ADS)

As has been shown in [Samsonov et al., 2013] even at the considerable disturbances of space weather parameters a healthy human being did not undergo painful symptoms although measurements of objective physiological indices showed their changes. At the same time the state of health of people with the weakened adaptation system under the same conditions can considerably be deteriorated up to fatal outcome. The analysis of results of the project "Heliomed" and the number of calls for the emergency medical care (EMC) around Yakutsk as to cardiovascular diseases (CVD) has shown:- the total number of calls for EMC concerning myocardial infarction (MI) per year near the geomagnetic disturbance maximum (1992) exceeds the number of calls per year near the geomagnetic activity minimum (1998) by a factor of 1,5 and concerning to strokes - by a factor of 1,8.- maxima of MI are observed during spring and autumn periods coinciding with maxima of geophysical disturbance;- the coincidence of 30-32 daily periods in a power spectrum of MI with the same periods in power spectra of space weather parameters (speeds and density of the solar wind, interplanetary magnetic field, geophysical disturbance);- the existence of 3 maxima of the number of calls for EMC: a) at the moment of disturbance on the Sun; during a geophysical disturbance (in 2-4 days after a disturbance on the Sun); in 2-4 days after a geophysical disturbance;- the availability of coincidence of insignificant disturbances of space weather parameters with changes of the functional state of cardiovascular system of a human being with the weakened adaptation system and the occurrence of MI and strokes at considerable values of such disturbances is explained by a quasi-logarithmic dependence of the response of human being organisms to the environment disturbance intensity.

Samsonov, S. N.

157

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

NASA Technical Reports Server (NTRS)

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).

Hooker, John C.

1991-01-01

158

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

PubMed Central

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

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

2014-01-01

159

A Reporting System for Non-Invasive Cardiovascular Investigations  

PubMed Central

A computer-based system has been developed to support the collection, reporting and storage of data acquired during non-invasive cardiac investigations. Currently the system serves 1-D echocardiography and graded exercise testing. Optical mark forms are used to record information in computer-readable form. A terminal station consisting of a CRT terminal, an optical mark reader and a printer is used for input and output from a central minicomputer database management system. Even when the costs associated with database storage are included, the overall cost of the system compares favorably with the option of using typists to produce reports.

Covvey, H.D.; Van Horik, M.; Hum, J.; Sole, M.J.; Schwartz, L.; Rakowski, H.; Wigle, E.D.

1978-01-01

160

A plausible radiobiological model of cardiovascular disease at low or fractionated doses  

NASA Astrophysics Data System (ADS)

Atherosclerosis is the main cause of coronary heart disease and stroke, the two major causes of death in developed society. There is emerging evidence of excess risk of cardiovascular disease at low radiation doses in various occupationally-exposed groups receiving small daily radia-tion doses. Assuming that they are causal, the mechanisms for effects of chronic fractionated radiation exposures on cardiovascular disease are unclear. We outline a spatial reaction-diffusion model for atherosclerosis, and perform stability analysis, based wherever possible on human data. We show that a predicted consequence of multiple small radiation doses is to cause mean chemo-attractant (MCP-1) concentration to increase linearly with cumulative dose. The main driver for the increase in MCP-1 is monocyte death, and consequent reduction in MCP-1 degradation. The radiation-induced risks predicted by the model are quantitatively consistent with those observed in a number of occupationally-exposed groups. The changes in equilibrium MCP-1 concentrations with low density lipoprotein cholesterol concentration are also consistent with experimental and epidemiologic data. This proposed mechanism would be experimentally testable. If true, it also has substantive implications for radiological protection, which at present does not take cardiovascular disease into account. The Japanese A-bomb survivor data implies that cardiovascular disease and can-cer mortality contribute similarly to radiogenic risk. The major uncertainty in assessing the low-dose risk of cardiovascular disease is the shape of the dose response relationship, which is unclear in the Japanese data. The analysis of the present paper suggests that linear extrapo-lation would be appropriate for this endpoint.

Little, Mark; Vandoolaeghe, Wendy; Gola, Anna; Tzoulaki, Ioanna

161

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

PubMed Central

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

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

2014-01-01

162

Cardiovascular Disease in Systemic Lupus Erythematosus: The Role of Traditional and Lupus Related Risk Factors  

PubMed Central

Atherosclerosis is a chronic inflammatory disorder characterized by immune cell activation, inflammation driven plaque formation and subsequent destabilization. In other disorders of an inflammatory nature, the chronic inflammatory state per se has been linked to acceleration of the atherosclerotic process which is underlined by an increased incidence of cardiovascular disease (CVD) in disorders such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and antiphopholipid (Hughes) syndrome (APS). SLE is an autoimmune disease that may affect any organ. Premature coronary heart disease has emerged as a major cause of morbidity and mortality in SLE. In addition to mortality, cardiovascular morbidity is also markedly increased in these patients, compared with the general population. The increased cardiovascular risk can be explained only partially by an increased prevalence of classical risk factors for cardiovascular disease; it also appears to be related to inflammation. Inflammation is increasingly being considered central to the pathogenesis of atherosclerosis and an important risk factor for vascular disease. Recent epidemiologic and pathogenesis studies have suggested a great deal in common between the pathogenesis of prototypic autoimmune disease such as SLE and that of atherosclerosis. We will review traditional risk factors for CVD in SLE. We will also discuss the role of inflammation in atherosclerosis, as well as possible treatment strategies in these patients. PMID:19936286

Zeller, Carlos Borelli; Appenzeller, Simone

2008-01-01

163

S-Nitrosothiols and the S-Nitrosoproteome of the Cardiovascular System  

PubMed Central

Abstract Significance: Since their discovery in the early 1990's, S-nitrosylated proteins have been increasingly recognized as important determinants of many biochemical processes. Specifically, S-nitrosothiols in the cardiovascular system exert many actions, including promoting vasodilation, inhibiting platelet aggregation, and regulating Ca2+ channel function that influences myocyte contractility and electrophysiologic stability. Recent Advances: Contemporary developments in liquid chromatography–mass spectrometry methods, the development of biotin- and His-tag switch assays, and the availability of cyanide dye-labeling for S-nitrosothiol detection in vitro have increased significantly the identification of a number of cardiovascular protein targets of S-nitrosylation in vivo. Critical Issues: Recent analyses using modern S-nitrosothiol detection techniques have revealed the mechanistic significance of S-nitrosylation to the pathophysiology of numerous cardiovascular diseases, including essential hypertension, pulmonary hypertension, ischemic heart disease, stroke, and congestive heart failure, among others. Future Directions: Despite enhanced insight into S-nitrosothiol biochemistry, translating these advances into beneficial pharmacotherapies for patients with cardiovascular diseases remains a primary as-yet unmet goal for investigators within the field. Antioxid. Redox Signal. 18, 270–287. PMID:22770551

Maron, Bradley A.; Tang, Shiow-Shih

2013-01-01

164

Sex and the cardiovascular system: the intriguing tale of how women and men regulate cardiovascular function differently  

Microsoft Academic Search

SOMETIMES, differences are, simply, annoying. Sometimes, they are illuminating and provide insight into hitherto hidden mech- anisms. So it appears to be when considering the cardiovascu- lar function and dysfunction of women and men. The purpose of this article is to highlight the features of cardiovascular function (e.g., pumping of the heart, blood flow control, pres- sure regulation, and solute

Virginia H. Huxley

2007-01-01

165

Probing Human Cardiovascular Congenital Disease Using Transgenic Mouse Models  

PubMed Central

Congenital heart defects (CHDs) impact in utero embryonic viability, children, and surviving adults. Since the first transfer of genes into mice, transgenic mouse models have enabled researchers to experimentally study and genetically test the roles of genes in development, physiology, and disease progression. Transgenic mice have become a bona fide human CHD pathology model and their use has dramatically increased within the past two decades. Now that the entire mouse and human genomes are known, it is possible to knock out, mutate, misexpress, and/or replace every gene. Not only have transgenic mouse models changed our understanding of normal development, CHD processes, and the complex interactions of genes and pathways required during heart development, but they are also being used to identify new avenues for medical therapy. PMID:21377625

Snider, Paige; Conway, Simon J.

2013-01-01

166

Dynamic three-dimensional reconstruction and modeling of cardiovascular anatomy in children with congenital heart disease using biplane angiography.  

PubMed

Modeling and simulation of cardiovascular biomechanics and fluid dynamics from patient-specific data is a continuing topic of research investigation. Several methodologies utilizing CT, MRI and ultrasound to re-create the three-dimensional anatomy of the cardiovascular system have been examined. Adaptation of these models to pediatric applications has not been studied as extensively. There is significant need for such techniques in pediatric congenital heart disease since local anatomy may exhibit highly unusual geometry, and three-dimensional information would be of significant use for surgical and interventional planning, biomechanical and fluid dynamic simulation, and patient counseling. We report here on the adaptation and application of a three-dimensional reconstruction technique that utilizes bi-plane angiographic images as the base data sets. The method has been validated in a variety of adult imaging situations including coronary artery imaging and intervention. The method uses a skeletonization approach whereby local centerline, diameter, branching and tortuosity of the vasculature are obtained to create the three-dimensional model. Ten patients with a variety of etiology were imaged and 3D reconstructions were obtained. Excellent images were obtained of complex anatomy including the highly branched pulmonary vasculature and Fontan surgical connections. The data were then translated into solid and surface models to facilitate viewing, export into computational fluid dynamic grids, and into files suitable for stereo lithography fabrication (STL). This method appears promising for the dynamic study of complex cardiovascular anatomy found in congenital heart disease. Optimization of the method to facilitate on-line reconstruction and simulation are currently ongoing. PMID:15133958

Lanning, Craig; Chen, S Y; Hansgen, Adam; Chang, Dennis; Chan, K Chen; Shandas, Robin

2004-01-01

167

In vitro cardiovascular system emulator (bioreactor) for the simulation of normal and diseased conditions with and without mechanical circulatory support.  

PubMed

This article presents a new device designed to simulate in vitro flow rates, pressures, and other parameters representing normal and diseased conditions of the human cardiovascular system. Such devices are sometimes called bioreactors or "mock" simulator of cardiovascular loops (SCVLs) in literature. Most SCVLs simulate the systemic circulation only and have inherent limitations in studying the interaction of left and right sides of circulation. Those SCVLs that include both left and right sides of the circulation utilize header reservoirs simulating cycles with constant atrial pressures. The SCVL described in this article includes models for all four chambers of the heart, and the systemic and pulmonary circulation loops. Each heart chamber is accurately activated by a separate linear motor to simulate the suction and ejection stages, thus capturing important features in the perfusion waveforms. Four mechanical heart valves corresponding to mitral, pulmonary, tricuspid, and aortic are used to control the desired unidirectional flow. This SCVL can emulate different physiological and pathological conditions of the human cardiovascular system by controlling the different parameters of blood circulation through the vascular tree (mainly the resistance, compliance, and elastance of the heart chambers). In this study, four cases were simulated: healthy, congestive heart failure, left ventricular diastolic dysfunction conditions, and left ventricular dysfunction with the addition of a mechanical circulatory support (MCS) device. Hemodynamic parameters including resistance, pressure, and flow have been investigated at aortic sinus, carotid artery, and pulmonary artery, respectively. The addition of an MCS device resulted in a significant reduction in mean blood pressure and re-establishment of cardiac output. In all cases, the experimental results are compared with human physiology and numerical simulations. The results show the capability of the SCVL to replicate various physiological and pathological conditions with and without MCS. PMID:23758568

Ruiz, Paula; Rezaienia, Mohammad Amin; Rahideh, Akbar; Keeble, Thomas R; Rothman, Martin T; Korakianitis, Theodosios

2013-06-01

168

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

PubMed Central

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

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

2012-01-01

169

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

ERIC Educational Resources Information Center

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)

Arnaudin, Mary W.; Mintzes, Joel J.

1986-01-01

170

Animal models of human cardiovascular disease, heart failure and hypertrophy  

Microsoft Academic Search

The progress made in our understanding of the pathophysiology and treatment of congestive heart failure (CHF) would not have been possible without a number of animal models of heart failure and hypertrophy, each one having unique advantages as well as disadvantages. The species and interventions used to create CHF depends on the scientific question as well as on factors such

Gerd Hasenfuss

171

Construction of an odds model of coronary heart disease using published information: the Cardiovascular Health Improvement Model (CHIME)  

PubMed Central

Background There is a need for a new cardiovascular disease model that includes a wider range of relevant risk factors, in particular lifestyle factors, to aid targeting of interventions and improve population models of the impact of cardiovascular disease and preventive strategies. The model needs to be applicable to a wider population including different ethnic groups, different countries and to those with and without cardiovascular disease. This paper describes the construction of the Cardiovascular Health Improvement Model that aims to meet these requirements. Method An odds model is used. Information was taken from 2003 mortality statistics for England and Wales, the Health Survey for England 2003 and published data on relative risk in those with and without CVD and mean blood pressure values in hypertensives. The odds ratios used were taken from the INTERHEART study. Results A worked example is given calculating the 10-year coronary heart disease risk for a 57 year-old non-diabetic male with no personal or family history of cardiovascular disease, who smokes 30 cigarettes a day and has a systolic blood pressure of 137 mmHg, a total cholesterol (TC) of 6.2 mmol/l, a high density lipoprotein (HDL) of 1.3 mol/l, and a body mass index of 21. He neither drinks regularly nor exercises. He can give no reliable information about his mental health or fruit and vegetable intake. His 10-year risk of CHD death is 2.47%. Conclusion This paper demonstrates a method for developing a CHD risk model. Further improvements could be made to the model with additional information. The method is applicable to other causes of death. PMID:18976488

Martin, Christopher J; Taylor, Paul; Potts, Henry WW

2008-01-01

172

Differential Distribution of Bradykinin B2 Receptors in the Rat and Human Cardiovascular System  

Microsoft Academic Search

Bradykinin, a major vasodilator peptide, plays an important role in the local regulation of blood pressure, blood flow, and vascular permeability; however, the cellular distribution of the major bradykinin B 2 receptor in the cardiovascular system is not precisely known. Immunoblot analysis with an anti-peptide antibody to the bradykinin B 2 receptor or chemical cross-linkage with (125I)Tyr0-bradykinin revealed a band

Carlos D. Figueroa; Alejandra Marchant; Ulises Novoa; Ulrich Forstermann; Kurt Jarnagin; Bernward Scholkens; Werner Muller-Esterl

173

Have the Renin-Angiotensin-Aldosterone System Perturbations in Cardiovascular Disease Been Exhausted?  

Microsoft Academic Search

The renin-angiotensin-aldosterone system (RAAS) plays an important role in blood pressure control and volume homeostasis.\\u000a Inappropriate activation of the RAAS has been implicated in the pathogenesis of hypertension and related cardiovascular disease.\\u000a Several classes of agents that block RAAS signaling have been shown to be effective antihypertensives and to have cardioprotective\\u000a and renoprotective properties. Because blockade of the RAAS is

Sulaf J. Mansur; Fadi G. Hage; Suzanne Oparil

2010-01-01

174

Spectrofluorimetric methods of stability-indicating assay of certain drugs affecting the cardiovascular system  

Microsoft Academic Search

Two stability-indicating spectrofluorimetric methods have been developed for the determination of ezetimibe and olmesartan medoxomil, drugs affecting the cardiovascular system, and validated in the presence of their degradation products. The first method, for ezetimibe, is based on an oxidative coupling reaction of ezetimibe with 3-methylbenzothiazolin-2-one hydrazone hydrochloride in the presence of cerium (IV) ammonium sulfate in an acidic medium. The

B. A. Moussa; M. F. Mohamed; N. F. Youssef

2011-01-01

175

Spectrofluorimetric methods of stability-indicating assay of certain drugs affecting the cardiovascular system  

Microsoft Academic Search

Two stability-indicating spectrofluorimetric methods have been developed for the determination of ezetimibe and olmesartan\\u000a medoxomil, drugs affecting the cardiovascular system, and validated in the presence of their degradation products. The first\\u000a method, for ezetimibe, is based on an oxidative coupling reaction of ezetimibe with 3-methylbenzothiazolin-2-one hydrazone\\u000a hydrochloride in the presence of cerium (IV) ammonium sulfate in an acidic medium. The

B. A. Moussa; M. F. Mohamed; N. F. Youssef

2011-01-01

176

Numerical fatigue life assessment of cardiovascular stents: A two-scale plasticity-damage model  

NASA Astrophysics Data System (ADS)

Cardiovascular disease has become a major global health care problem in the last decades. To tackle this problem, the use of cardiovascular stents has been considered a promising and effective approach. Numerical simulations to evaluate the in vivo behavior of stents are becoming more and more important to assess potential failures. As the material failure of a stent device has been often associated with fatigue issues, numerical approaches for fatigue life assessment of stents have gained special interest in the engineering community. Numerical fatigue life predictions can be used to modify the design and prevent failure without making and testing numerous physical devices, thus preventing from undesired fatigue failures. We present a numerical fatigue life model for the analysis of cardiovascular balloon-expandable stainless steel stents that can hopefully provide useful information either to be used for product improvement or for clinicians to make life-saving decisions. This model incorporates a two-scale continuum damage mechanics model and the so-called Soderberg fatigue failure criterion. We provide numerical results for both Palmaz-Schatz and Cypher stent designs and demonstrate that a good agreement is found between the numerical and the available experimental results.

Santos, H. A. F. A.; Auricchio, F.; Conti, M.

2013-07-01

177

Development of patient specific cardiovascular models predicting dynamics  

E-print Network

) and a hypertensive elderly (right) subject. 50 55 60 65 70 75 80 85 90 0 20 40 60 80 100 120 140 time [sec) and a hypertensive elderly (right) subject. 3 #12;50 60 70 80 90 40 50 60 70 80 90 100 time [sec] HR[bpm] Model Data elderly subjects, while the pulse velocity (the width - the systolic minus the diastolic value for each

178

Systolic time interval data acquisition system. Specialized cardiovascular studies  

NASA Technical Reports Server (NTRS)

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.

Baker, J. T.

1976-01-01

179

Nnuclear uptake and retention of a synthetic progestin in the cardiovascular system of the baboon  

SciTech Connect

It has long been known that there is a sexual dimorphism in the incidence of coronary heart disease. This observation, together with more recent reports of increased cardiovascular disease associated with the use of oral contraceptives, led to a search for steroid receptors in the cardiovascular system. In this study the nuclear uptake and retention of a synthetic progestin was examined in the cardiovascular system of the baboons. Long term oophorectomized baboons were primed with estradiol benzoate for 3 days before the experiment (50 micrograms/kg, im) and adrenalectomized 2 days before the experiment. On the day of the experiment, the animals were injected under anesthesia with 2.5 micrograms/kg BW (/sup 3/H)ORG 2058 (16 alpha-ethyl-21-hydroxy-19-nor-(6,7-/sup 3/H)pregn-4-ene-3,20-dione) or with (/sup 3/H) ORG 2058 plus a 1000-fold excess of unlabeled progesterone (control). One hour after the injection, the animals were rapidly exsanguinated, and parts of the cardiovascular system were removed and processed for autoradiography. Localization of the synthetic progestin was found in nuclei of between 25-75% of all smooth muscle cells of the media of all arteries examined and to a lesser extent in the nuclei of the fibroblasts and others cells of the adventitia. Localization of the synthetic progestin in the heart was limited to approximately 1% of the myocardial cells and less than 5% of interstitial cell nuclei. The pattern of localization found differs from that for estrogen and androgen and suggests the possible presence of estrogen-independent progesterone receptors in smooth muscle cells of the media of the aorta and coronary arteries.

Sheridan, P.J.; McGill, H.C. Jr.

1984-06-01

180

Effects of exercise training on cardiovascular adrenergic system  

PubMed Central

In heart failure (HF), exercise has been shown to modulate cardiac sympathetic hyperactivation which is one of the earliest features of neurohormonal derangement in this syndrome and correlates with adverse outcome. An important molecular alteration related to chronic sympathetic overstimulation in HF is represented by cardiac ?-adrenergic receptor (?-AR) dysfunction. It has been demonstrated that exercise reverses ?-AR dysfunction by restoring cardiac receptor membrane density and G-protein-dependent adenylyl cyclase activation. In particular, several evidence indicate that exercise reduces levels of cardiac G-protein coupled receptor kinase-2 (GRK2) which is known to be involved in both ?1-AR and ?2-AR dysregulation in HF. Similar alterations of ?-AR system have been described also in the senescent heart. It has also been demonstrated that exercise training restores adrenal GRK2/?-2AR/catecholamine (CA) production axis. At vascular level, exercise shows a therapeutic effect on age-related impairment of vascular reactivity to adrenergic stimulation and restores ?-AR-dependent vasodilatation by increasing vascular ?-AR responsiveness and reducing endothelial GRK2 activity. Sympathetic nervous system overdrive is thought to account for >50% of all cases of hypertension and a lack of balance between parasympathetic and sympathetic modulation has been observed in hypertensive subjects. Non-pharmacological, lifestyle interventions have been associated with reductions in SNS overactivity and blood pressure in hypertension. Several evidence have highlighted the blood pressure lowering effects of aerobic endurance exercise in patients with hypertension and the significant reduction in sympathetic neural activity has been reported as one of the main mechanisms explaining the favorable effects of exercise on blood pressure control. PMID:24348425

Leosco, Dario; Parisi, Valentina; Femminella, Grazia D.; Formisano, Roberto; Petraglia, Laura; Allocca, Elena; Bonaduce, Domenico

2013-01-01

181

A Simple Chinese Risk Score Model for Screening Cardiovascular Autonomic Neuropathy  

PubMed Central

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

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

2014-01-01

182

Vascular Stiffness and Increased Pulse Pressure in the Aging Cardiovascular System  

PubMed Central

Aging leads to a multitude of changes in the cardiovascular system, including systolic hypertension, increased central vascular stiffness, and increased pulse pressure. In this paper we will review the effects of age-associated increased vascular stiffness on systolic blood pressure, pulse pressure, augmentation index, and cardiac workload. Additionally we will describe pulse wave velocity as a method to measure vascular stiffness and review the impact of increased vascular stiffness as an index of vascular health and as a predictor of adverse cardiovascular outcomes. Furthermore, we will discuss the underlying mechanisms and how these may be modified in order to change the outcomes. A thorough understanding of these concepts is of paramount importance and has therapeutic implications for the increasingly elderly population. PMID:21845218

Steppan, Jochen; Barodka, Viachaslau; Berkowitz, Dan E.; Nyhan, Daniel

2011-01-01

183

Mechanosensitive Channels in Striated Muscle and the Cardiovascular System: Not Quite a Stretch Anymore  

PubMed Central

Stretch-activated or mechanosensitive channels transduce mechanical forces into ion fluxes across the cell membrane. These channels have been implicated in several aspects of cardiovascular physiology including regulation of blood pressure, vasoreactivity, and cardiac arrhythmias as well as the adverse remodeling associated with cardiac hypertrophy and heart failure. This review discusses mechanosensitive channels in skeletal muscle and the cardiovascular system and their role in disease pathogenesis. We describe the regulation of gating of mechanosensitive channels including direct mechanisms and indirect activation by signaling pathways, as well as the influence on activation of these channels by the underlying cytoskeleton and scaffolding proteins. We then focus on the role of transient receptor potential channels, several of which have been implicated as mechanosensitive channels, in the pathogenesis of adverse cardiac remodeling and as potential therapeutic targets in the treatment of heart failure. PMID:19597371

Stiber, Jonathan A.; Seth, Malini; Rosenberg, Paul B.

2013-01-01

184

Physical activity ameliorates cardiovascular health in elderly subjects: the functional role of the ? adrenergic system  

PubMed Central

Aging is a complex process characterized by a gradual decline in organ functional reserves, which eventually reduces the ability to maintain homeostasis. An exquisite feature of elderly subjects, which constitute a growing proportion of the world population, is the high prevalence of cardiovascular disorders, which negatively affect both the quality of life and the life expectancy. It is widely acknowledged that physical activity represents one of the foremost interventions capable in reducing the health burden of cardiovascular disease. Interestingly, the benefits of moderate-intensity physical activity have been established both in young and elderly subjects. Herein we provide a systematic and updated appraisal of the literature exploring the pathophysiological mechanisms evoked by physical activity in the elderly, focusing on the functional role of the ? adrenergic system. PMID:23964243

Santulli, Gaetano; Ciccarelli, Michele; Trimarco, Bruno; Iaccarino, Guido

2013-01-01

185

REVIEW Modelling the lymphatic system:  

E-print Network

The lymphatic system is a vital part of the circulatory and immune systems, and plays an important role in homeostasis by controlling extracellular fluid volume and in combating infection. Nevertheless, there is a notable disparity in terms of research effort expended in relation to the treatment of lymphatic diseases in contrast to the cardiovascular system. While similarities to the cardiovascular system exist, there are considerable differences in their anatomy and physiology. This review outlines some of the challenges and opportunities for those engaged in modelling biological systems. The study of the lymphatic system is still in its infancy, the vast majority of the models presented in the literature to date having been developed since 2003. The number of distinct models and their variants are few in number, and only one effort has been made thus far to study the entire lymphatic network; elements of the lymphatic system such as the nodes, which act as pumps and reservoirs, have not been addressed by mathematical models. Clearly, more work will be necessary in combination with experimental verification in order to progress and update the knowledge on the function of the lymphatic system. As our knowledge and understanding of its function increase, new and more effective treatments of lymphatic diseases are bound to emerge.

K. N. Margaris; R. A. Black

2012-01-01

186

Cardiovascular risk  

PubMed Central

Cardiovascular disease is a major, growing, worldwide problem. It is important that individuals at risk of developing cardiovascular disease can be effectively identified and appropriately stratified according to risk. This review examines what we understand by the term risk, traditional and novel risk factors, clinical scoring systems, and the use of risk for informing prescribing decisions. Many different cardiovascular risk factors have been identified. Established, traditional factors such as ageing are powerful predictors of adverse outcome, and in the case of hypertension and dyslipidaemia are the major targets for therapeutic intervention. Numerous novel biomarkers have also been described, such as inflammatory and genetic markers. These have yet to be shown to be of value in improving risk prediction, but may represent potential therapeutic targets and facilitate more targeted use of existing therapies. Risk factors have been incorporated into several cardiovascular disease prediction algorithms, such as the Framingham equation, SCORE and QRISK. These have relatively poor predictive power, and uncertainties remain with regards to aspects such as choice of equation, different risk thresholds and the roles of relative risk, lifetime risk and reversible factors in identifying and treating at-risk individuals. Nonetheless, such scores provide objective and transparent means of quantifying risk and their integration into therapeutic guidelines enables equitable and cost-effective distribution of health service resources and improves the consistency and quality of clinical decision making. PMID:22348281

Payne, Rupert A

2012-01-01

187

Cardiovascular risk.  

PubMed

Cardiovascular disease is a major, growing, worldwide problem. It is important that individuals at risk of developing cardiovascular disease can be effectively identified and appropriately stratified according to risk. This review examines what we understand by the term risk, traditional and novel risk factors, clinical scoring systems, and the use of risk for informing prescribing decisions. Many different cardiovascular risk factors have been identified. Established, traditional factors such as ageing are powerful predictors of adverse outcome, and in the case of hypertension and dyslipidaemia are the major targets for therapeutic intervention. Numerous novel biomarkers have also been described, such as inflammatory and genetic markers. These have yet to be shown to be of value in improving risk prediction, but may represent potential therapeutic targets and facilitate more targeted use of existing therapies. Risk factors have been incorporated into several cardiovascular disease prediction algorithms, such as the Framingham equation, SCORE and QRISK. These have relatively poor predictive power, and uncertainties remain with regards to aspects such as choice of equation, different risk thresholds and the roles of relative risk, lifetime risk and reversible factors in identifying and treating at-risk individuals. Nonetheless, such scores provide objective and transparent means of quantifying risk and their integration into therapeutic guidelines enables equitable and cost-effective distribution of health service resources and improves the consistency and quality of clinical decision making. PMID:22348281

Payne, Rupert A

2012-09-01

188

Simulation of a G-tolerance curve using the pulsatile cardiovascular model  

NASA Technical Reports Server (NTRS)

A computer simulation study, performed to assess the ability of the cardiovascular model to reproduce the G tolerance curve (G level versus tolerance time) is reported. A composite strength duration curve derived from experimental data obtained in human centrifugation studies was used for comparison. The effects of abolishing automomic control and of blood volume loss on G tolerance were also simulated. The results provide additional validation of the model. The need for the presence of autonomic reflexes even at low levels of G is pointed out. The low margin of safety with a loss of blood volume indicated by the simulation results underscores the necessity for protective measures during Shuttle reentry.

Solomon, M.; Srinivasan, R.

1985-01-01

189

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

PubMed Central

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

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

2014-01-01

190

Ventilatory and cardiovascular responses to hypoxia and hypercapnia in multiple system atrophy  

PubMed Central

Objective To determine whether ventilatory and cardiovascular responses to hypercapnia and hypoxia during wakefulness are systematically impaired in multiple system atrophy (MSA). Method Case-control study on minute ventilation, blood pressure, and heart rate responses to hypercapnia and hypoxia in 16 patients with probable MSA and 14 age-matched controls during wakefulness. Hypercapnia was induced by a rebreathing technique and limited to an expiratory partial pressure of CO2 (Pet CO2) ? 65mmHg. Hypoxia was induced by a step-wise increase in inspired nitrogen partial pressure and limited to a minimal oxygen saturation (SaO2) of 80%. Ventilatory responses were assessed as slopes of the regression line relating minute ventilation to changes in SaO2 and PetCO2, respectively. Results Ventilatory responses to hypercapnia and hypoxia where preserved in MSA patients, despite the presence of severe autonomic failure. In contrast, cardiovascular responses to these stimuli were impaired in MSA. Compared to controls, hypercapnia elicited less robust increase in arterial pressure (p < 0.001) and hypoxia elicited a depressor rather than the normal pressor responses (p <0.001). Conclusion Ventilatory responses to hypercapnia and hypoxia during wakefulness may be preserved in MSA patients despite the presence of autonomic failure and impaired cardiovascular responses to these stimuli. This suggests that a critical number of chemosensitive medullary neurons must be lost before development of impaired automatic ventilation during wakefulness in MSA, whereas earlier loss of medullary sympathoexcitatory neurons may contribute to the impaired cardiovascular responses in these patients. PMID:20142529

Lipp, Axel; Schmelzer, James D.; Low, Phillip A.; Johnson, Bruce D.; Benarroch, Eduardo E.

2010-01-01

191

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

PubMed Central

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

Coelho, Ken Russell

2013-01-01

192

Cardiovascular Actions of Neurotrophins  

PubMed Central

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

CAPORALI, ANDREA; EMANUELI, COSTANZA

2010-01-01

193

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

Microsoft Academic Search

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

Stephanie O. Keeling; Michelle Teo; Daisy Fung

194

Methods for establishing a surveillance system for cardiovascular diseases in Indian industrial populations.  

PubMed Central

OBJECTIVE: To establish a surveillance network for cardiovascular diseases (CVD) risk factors in industrial settings and estimate the risk factor burden using standardized tools. METHODS: We conducted a baseline cross-sectional survey (as part of a CVD surveillance programme) of industrial populations from 10 companies across India, situated in close proximity to medical colleges that served as study centres. The study subjects were employees (selected by age and sex stratified random sampling) and their family members. Information on behavioural, clinical and biochemical determinants was obtained through standardized methods (questionnaires, clinical measurements and biochemical analysis). Data collation and analyses were done at the national coordinating centre. FINDINGS: We report the prevalence of CVD risk factors among individuals aged 20-69 years (n = 19 973 for the questionnaire survey, n = 10 442 for biochemical investigations); mean age was 40 years. The overall prevalence of most risk factors was high, with 50.9% of men and 51.9% of women being overweight, central obesity was observed among 30.9% of men and 32.8% of women, and 40.2% of men and 14.9% of women reported current tobacco use. Self-reported prevalence of diabetes (5.3%) and hypertension (10.9%) was lower than when measured clinically and biochemically (10.1% and 27.7%, respectively). There was marked heterogeneity in the prevalence of risk factors among the study centres. CONCLUSION: There is a high burden of CVD risk factors among industrial populations across India. The surveillance system can be used as a model for replication in India as well as other developing countries. PMID:16799730

Reddy, K. S.; Prabhakaran, D.; Chaturvedi, V.; Jeemon, P.; Thankappan, K. R.; Ramakrishnan, L.; Mohan, B. V. M.; Pandav, C. S.; Ahmed, F. U.; Joshi, P. P.; Meera, R.; Amin, R. B.; Ahuja, R. C.; Das, M. S.; Jaison, T. M.

2006-01-01

195

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

PubMed Central

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

da Silva, Maria de Lourdes Costa; Galvăo, 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

196

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

PubMed

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

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

197

Absence of Cardiovascular Manifestations in a Haploinsufficient Tgfbr1 Mouse Model  

PubMed Central

Loeys-Dietz syndrome (LDS) is an autosomal dominant arterial aneurysm disease belonging to the spectrum of transforming growth factor ? (TGF?)-associated vasculopathies. In its most typical form it is characterized by the presence of hypertelorism, bifid uvula/cleft palate and aortic aneurysm and/or arterial tortuosity. LDS is caused by heterozygous loss of function mutations in the genes encoding TGF? receptor 1 and 2 (TGFBR1 and ?2), which lead to a paradoxical increase in TGF? signaling. To address this apparent paradox and to gain more insight into the pathophysiology of aneurysmal disease, we characterized a new Tgfbr1 mouse model carrying a p.Y378* nonsense mutation. Study of the natural history in this model showed that homozygous mutant mice die during embryonic development due to defective vascularization. Heterozygous mutant mice aged 6 and 12 months were morphologically and (immuno)histochemically indistinguishable from wild-type mice. We show that the mutant allele is degraded by nonsense mediated mRNA decay, expected to result in haploinsufficiency of the mutant allele. Since this haploinsufficiency model does not result in cardiovascular malformations, it does not allow further study of the process of aneurysm formation. In addition to providing a comprehensive method for cardiovascular phenotyping in mice, the results of this study confirm that haploinsuffciency is not the underlying genetic mechanism in human LDS. PMID:24587008

Renard, Marjolijn; Trachet, Bram; Casteleyn, Christophe; Campens, Laurence; Cornillie, Pieter; Callewaert, Bert; Deleye, Steven; Vandeghinste, Bert; van Heijningen, Paula M.; Dietz, Harry; De Vos, Filip; Essers, Jeroen; Staelens, Steven; Segers, Patrick; Loeys, Bart; Coucke, Paul; De Paepe, Anne; De Backer, Julie

2014-01-01

198

Absence of cardiovascular manifestations in a haploinsufficient Tgfbr1 mouse model.  

PubMed

Loeys-Dietz syndrome (LDS) is an autosomal dominant arterial aneurysm disease belonging to the spectrum of transforming growth factor ? (TGF?)-associated vasculopathies. In its most typical form it is characterized by the presence of hypertelorism, bifid uvula/cleft palate and aortic aneurysm and/or arterial tortuosity. LDS is caused by heterozygous loss of function mutations in the genes encoding TGF? receptor 1 and 2 (TGFBR1 and -2), which lead to a paradoxical increase in TGF? signaling. To address this apparent paradox and to gain more insight into the pathophysiology of aneurysmal disease, we characterized a new Tgfbr1 mouse model carrying a p.Y378* nonsense mutation. Study of the natural history in this model showed that homozygous mutant mice die during embryonic development due to defective vascularization. Heterozygous mutant mice aged 6 and 12 months were morphologically and (immuno)histochemically indistinguishable from wild-type mice. We show that the mutant allele is degraded by nonsense mediated mRNA decay, expected to result in haploinsufficiency of the mutant allele. Since this haploinsufficiency model does not result in cardiovascular malformations, it does not allow further study of the process of aneurysm formation. In addition to providing a comprehensive method for cardiovascular phenotyping in mice, the results of this study confirm that haploinsuffciency is not the underlying genetic mechanism in human LDS. PMID:24587008

Renard, Marjolijn; Trachet, Bram; Casteleyn, Christophe; Campens, Laurence; Cornillie, Pieter; Callewaert, Bert; Deleye, Steven; Vandeghinste, Bert; van Heijningen, Paula M; Dietz, Harry; De Vos, Filip; Essers, Jeroen; Staelens, Steven; Segers, Patrick; Loeys, Bart; Coucke, Paul; De Paepe, Anne; De Backer, Julie

2014-01-01

199

Age-related changes in pharmacodynamics: focus on drugs acting on central nervous and cardiovascular systems.  

PubMed

Aging is characterized by progressive impairment of functional capacities of all system organs, reduction in homeostatic mechanisms, and altered response to receptor stimulation. These age-related physiologic changes influence both pharmacokinetics and pharmacodynamics of drugs in elderly patients. Pharmacokinetic and pharmacodynamics changes as well as polypharmacy and comorbidities may alter significantly the effect of pharmacological treatment with advancing age. With the same drug concentration at the site of action, significant differences in the response to several drugs have been observed in older patients as compared to younger patients. Elderly patients are particularly suceptibles to the effects of frequently prescribed drugs acting on central nervous system, such as benzodiazepines, antidepressants, antipsychotics and lithium, with high potential for adverse drug reactions. Moreover, in older patients increased sensitivity to warfarin resulting in increased risk of bleeding has been previously documented. On the other hand, reduced effectiveness of conventional doses of cardiovascular drugs, such as diuretics and ?-blockers, has been observed. Due to pharmacodynamic changes, therefore, dose adjustment of the above mentioned cardiovascular and psychotropic drugs is recommended in elderly. Clinicians should be aware of the age-related physiologic changes affecting several organ systems and their implications on the effect of drugs that are commonly prescribed to elderly patients. PMID:21495972

Trifirň, Gianluca; Spina, Edoardo

2011-09-01

200

Space Weather and the State of Cardiovascular System of a Healthy Human Being  

NASA Astrophysics Data System (ADS)

The term "space weather" characterizes a state of the near-Earth environmental space. An organism of human being represents an open system so the change of conditions in the environment including the near-Earth environmental space influences the health state of a human being.In recent years many works devoted to the effect of space weather on the life on the Earth, and the degree of such effect has been represented from a zero-order up to apocalypse. To reveal a real effect of space weather on the health of human being the international Russian- Ukrainian experiment "Geliomed" is carried out since 2005 (http://geliomed.immsp.kiev.ua) [Vishnevsky et al., 2009]. The analysis of observational set of data has allowed to show a synchronism and globality of such effect (simultaneous manifestation of space weather parameters in a state of cardiovascular system of volunteer groups removed from each other at a distance over 6000 km). The response of volunteer' cardiovascular system to the changes of space weather parameters were observed even at insignificant values of the Earth's geomagnetic field. But even at very considerable disturbances of space weather parameters a human being healthy did not feel painful symptoms though measurements of objective physiological indices showed their changes.

Samsonov, S. N.; Manykina, V. I.; Krymsky, G. F.; Petrova, P. G.; Palshina, A. M.; Vishnevsky, V. V.

201

The peripheral-type benzodiazepine receptor and the cardiovascular system. Implications for drug development.  

PubMed

Peripheral-type benzodiazepine receptors (PBRs) are abundant in the cardiovascular system. In the cardiovascular lumen, PBRs are present in platelets, erythrocytes, lymphocytes, and mononuclear cells. In the walls of the cardiovascular system, PBR can be found in the endothelium, the striated cardiac muscle, the vascular smooth muscles, and the mast cells. The subcellular location of PBR is primarily in mitochondria. The PBR complex includes the isoquinoline binding protein (IBP), voltage-dependent anion channel (VDAC), and adenine nucleotide transporter (ANT). Putative endogenous ligands for PBR include protoporphyrin IX, diazepam binding inhibitor (DBI), triakontatetraneuropeptide (TTN), and phospholipase A2 (PLA2). Classical synthetic ligands for PBR are the isoquinoline 1-(2-chlorophenyl)-N-methyl-N-(1-methyl-propyl)-3-isoquinolinecarboxamide (PK 11195) and the benzodiazepine 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one (Ro5 4864). Novel PBR ligands include N,N-di-n-hexyl 2-(4-fluorophenyl)indole-3-acetamide (FGIN-1-27) and 7-chloro-N,N,5-trimethyl-4-oxo-3-phenyl-3,5-dihydro-4H-pyridazino[4,5-b]indole-1-acetamide (SSR180575), both possessing steroidogenic properties, but while FGIN-1-27 is pro-apoptotic, SSR180575 is anti-apoptotic. Putative PBR functions include regulation of steroidogenesis, apoptosis, cell proliferation, the mitochondrial membrane potential, the mitochondrial respiratory chain, voltage-dependent calcium channels, responses to stress, and microglial activation. PBRs in blood vessel walls appear to take part in responses to trauma such as ischemia. The irreversible PBR antagonist, SSR180575, was found to reduce damage correlated with ischemia. Stress, anxiety disorders, and neurological disorders, as well as their treatment, can affect PBR levels in blood cells. PBRs in blood cells appear to play roles in several aspects of the immune response, such as phagocytosis and the secretion of interleukin-2, interleukin-3, and immunoglobulin A (IgA). Thus, alterations in PBR density in blood cells may have immunological consequences in the affected person. In conclusion, PBR in the cardiovascular system may represent a new target for drug development. PMID:16337685

Veenman, Leo; Gavish, Moshe

2006-06-01

202

Major pathways of the reno–cardiovascular link: the sympathetic and renin–angiotensin systems  

PubMed Central

Chronic kidney disease is often characterized by enhanced activity of the renin–angiotensin system (RAS) and the sympathetic nervous system. Independent of their effect on blood pressure, these systems also contribute to the pathogenesis of both structural and functional cardiovascular abnormalities and contribute importantly to clinical outcome. There is much evidence that the diseased kidneys are of central importance in the pathogenesis of both abnormalities. Inhibitors of the RAS also reduce sympathetic overactivity. Future research should be aimed at addressing the pathophysiological mechanisms causing the enhanced activities. Given the fact that even a small kidney lesion can cause enhanced activity of the RAS and the sympathetic nervous system, it is likely that these pathophysiological mechanisms are operational in more disease conditions, including essential hypertension, heart failure, and obesity/metabolic syndrome. PMID:25018897

Blankestijn, Peter J; London, Gerard; Fliser, Danilo; Jager, Kitty J; Lindholm, Bengt; Goldsmith, David; Wiecek, Andrzej; Suleymanlar, Gultekin; Agarwal, Rajiv; Ortiz, Alberto; Massy, Ziad; Martinez-Castelao, Alberto; Covic, Adrian; Dekker, Friedo W; Zoccali, Carmine

2011-01-01

203

IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL. 55, NO. 1, JANUARY 2008 119 Statistical Modeling of Cardiovascular  

E-print Network

of Cardiovascular Signals and Parameter Estimation Based on the Extended Kalman Filter James McNames, Senior Member, IEEE, and Mateo Aboy*, Member, IEEE Abstract--Cardiovascular signals such as arterial blood pres- sure of cardiovascular signals and describe how it can be used with the extended Kalman filter (EKF) to simultaneously

204

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

PubMed Central

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

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

2012-01-01

205

Laser-based optoelectronic system for therapy by medical treatment of cardiovascular diseases  

NASA Astrophysics Data System (ADS)

The method and design of a system for the laser treatment of ischemic heart disease is presented. Our conceptual approach to the development of the system is based on the theoretical and experimental works of the east and west scientists about positive influence of low intensity laser irradiation in the near infrared range by treatment of cardiovascular diseases. The method and system allow active influence on the subepicardial collateral blood circulation with near infrared (NIR) laser irradiation in wavelength ranges of 0.86-1.06 mkm. The presented technique makes it possible to achieve a higher effectiveness of treatment due to individual choice of radiation parameters on the basis of analysis of the patient conditions before and after laser therapy and due to simultaneous affection at several points of the human body. Finally, results of the tests are presented, which prove given methods.

Chtchoupak, Oleg S.; Shpilevoj, Boris N.; Zapaeva, Natlia L.

1996-01-01

206

Laser-based optoelectronic system for therapy by medical treatment of cardiovascular diseases  

NASA Astrophysics Data System (ADS)

The method and system's design for the laser treatment of the heart ischemia is presented. Our conceptual approach to the development of the system is based on the theoretical and experimental works about positive influence of low intensity near infrared laser irradiation by treatment of cardiovascular diseases. The method and system allow it to influence the subepicardial collateral blood circulation with near infrared (NIR) laser irradiation in wavelength ranges of 0.86 - 1.06 mkm. The presented techniques make it possible to achieve a higher effectiveness of treatment. First, due to individual choice of radiation parameters on the basis of analysis of the patient's conditions before and after laser therapy. Second, due to simultaneous influence at several points of the human body. Finally, results of the clinical tests are presented, which confirm the discussed methods.

Chtchoupak, Oleg S.; Spilevoi, Boris N.; Zapaeva, Natlia L.

1996-04-01

207

An optical multi-sensing system for detection of cardiovascular toxicity.  

PubMed

A mini-microscope-based system for multisite detection of cardiovascular toxicity was developed. The mini-microscope consisted of an image sensor and lens module extracted from an inexpensive webcam. The flipped lens module enabled cells to be magnified and monitored during testing. The portability and compactness of this system enables short-term and potential long-term experimentation inside a conventional incubator. The toxicity test results demonstrated that the normalized beating rates of cardiac muscle cells selected from multiple regions increased over time when treated with 100 nM isoprenaline. The presented system could be a promising cost-effective cell-based testing tool for discovering and screening drugs. PMID:24563288

Koo, Kyo-in; Kim, Sang Bok; Kim, Keekyoung; Oh, Jonghyun

2014-05-01

208

Flipped classroom model improves graduate student performance in cardiovascular, respiratory, and renal physiology.  

PubMed

The purpose of this study was to assess the effectiveness of a traditional lecture-based curriculum versus a modified "flipped classroom" curriculum of cardiovascular, respiratory, and renal physiology delivered to first-year graduate students. Students in both courses were provided the same notes and recorded lectures. Students in the modified flipped classroom were required to watch the prerecorded lectures before class and then attend class, where they received a quiz or homework covering material in each lecture (valued at 25% of the final grade) followed by a question and answer/problem-solving period. In the traditional curriculum, attending lectures was optional and there were no quizzes. Evaluation of effectiveness and student performance was achieved by having students in both courses take the same multiple-choice exams. Within a comparable group of graduate students, participants in the flipped course scored significantly higher (P ? 0.05) on the cardiovascular, respiratory, and weighted cumulative sections by an average of >12 percentage points. Exam averages for students in the flipped course also tended to be higher on the renal section by ?11 percentage points (P = 0.06). Based on our experience and responses obtained in blinded student surveys, we propose that the use of homework and in-class quizzes were critical motivating factors that likely contributed to the increase in student exam performance. Taken together, our findings support that the flipped classroom model is a highly effective means in which to disseminate key physiological concepts to graduate students. PMID:24292907

Tune, Johnathan D; Sturek, Michael; Basile, David P

2013-12-01

209

Low-grade systemic inflammation connects aging, metabolic syndrome and cardiovascular disease.  

PubMed

Aging is associated with immunosenescence and accompanied by a chronic inflammatory state which contributes to metabolic syndrome, diabetes and their cardiovascular consequences. Risk factors for cardiovascular diseases (CVDs) and diabetes overlap, leading to the hypothesis that both share an inflammatory basis. Obesity is increased in the elderly population, and adipose tissue induces a state of systemic inflammation partially induced by adipokines. The liver plays a pivotal role in the metabolism of nutrients and exhibits alterations in the expression of genes associated with inflammation, cellular stress and fibrosis. Hepatic steatosis and its related inflammatory state (steatohepatitis) are the main hepatic complications of obesity and metabolic diseases. Aging-linked declines in expression and activity of endoplasmic reticulum molecular chaperones and folding enzymes compromise proper protein folding and the adaptive response of the unfolded protein response. These changes predispose aged individuals to CVDs. CVDs and endothelial dysfunction are characterized by a chronic alteration of inflammatory function and markers of inflammation and the innate immune response, including C-reactive protein, interleukin-6, TNF-?, and several cell adhesion molecules are linked to the occurrence of myocardial infarction and stroke in healthy elderly populations and patients with metabolic diseases. PMID:25341516

Guarner, Verónica; Rubio-Ruiz, Maria Esther

2015-01-01

210

Unusual fistulas and connections in the cardiovascular system: A pictorial review  

PubMed Central

A fistula is an abnormal vascular connection leading to diversion of blood from a high resistance arterial circuit to low resistance venous circuit. Coronary artery fistulas are abnormal communications of the coronary artery with a chamber of the heart, or with any segment of systemic or pulmonary circulation, bypassing the myocardial capillaries. Other unusual fistulas include connection between aorta and the right atrium/superior vena cava, aorta and the inferior vena cava or between a coronary artery bypass graft and a cardiac vein. Abnormal connections also include origin of the coronary artery from the pulmonary artery. In this article, we review the imaging, particularly computed tomography and magnetic resonance imaging of unusual fistulas and connections involving the cardiovascular system, particularly the coronary arteries and the aorta. PMID:24876921

Ghandour, Abed; Rajiah, Prabhakar

2014-01-01

211

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

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

212

The kallikrein-kinin system as a regulator of cardiovascular and renal function.  

PubMed

Autocrine, paracrine, endocrine, and neuroendocrine hormonal systems help regulate cardio-vascular and renal function. Any change in the balance among these systems may result in hypertension and target organ damage, whether the cause is genetic, environmental or a combination of the two. Endocrine and neuroendocrine vasopressor hormones such as the renin-angiotensin system (RAS), aldosterone, and catecholamines are important for regulation of blood pressure and pathogenesis of hypertension and target organ damage. While the role of vasodepressor autacoids such as kinins is not as well defined, there is increasing evidence that they are not only critical to blood pressure and renal function but may also oppose remodeling of the cardiovascular system. Here we will primarily be concerned with kinins, which are oligopeptides containing the aminoacid sequence of bradykinin. They are generated from precursors known as kininogens by enzymes such as tissue (glandular) and plasma kallikrein. Some of the effects of kinins are mediated via autacoids such as eicosanoids, nitric oxide (NO), endothelium-derived hyperpolarizing factor (EDHF), and/or tissue plasminogen activator (tPA). Kinins help protect against cardiac ischemia and play an important part in preconditioning as well as the cardiovascular and renal protective effects of angiotensin-converting enzyme (ACE) and angiotensin type 1 receptor blockers (ARB). But the role of kinins in the pathogenesis of hypertension remains controversial. A study of Utah families revealed that a dominant kallikrein gene expressed as high urinary kallikrein excretion was associated with a decreased risk of essential hypertension. Moreover, researchers have identified a restriction fragment length polymorphism (RFLP) that distinguishes the kallikrein gene family found in one strain of spontaneously hypertensive rats (SHR) from a homologous gene in normotensive Brown Norway rats, and in recombinant inbred substrains derived from these SHR and Brown Norway rats this RFLP cosegregated with an increase in blood pressure. However, humans, rats and mice with a deficiency in one or more components of the kallikrein-kinin-system (KKS) or chronic KKS blockade do not have hypertension. In the kidney, kinins are essential for proper regulation of papillary blood flow and water and sodium excretion. B2-KO mice appear to be more sensitive to the hypertensinogenic effect of salt. Kinins are involved in the acute antihypertensive effects of ACE inhibitors but not their chronic effects (save for mineralocorticoid-salt-induced hypertension). Kinins appear to play a role in the pathogenesis of inflammatory diseases such as arthritis and skin inflammation; they act on innate immunity as mediators of inflammation by promoting maturation of dendritic cells, which activate the body's adaptive immune system and thereby stimulate mechanisms that promote inflammation. On the other hand, kinins acting via NO contribute to the vascular protective effect of ACE inhibitors during neointima formation. In myocardial infarction produced by ischemia/reperfusion, kinins help reduce infarct size following preconditioning or treatment with ACE inhibitors. In heart failure secondary to infarction, the therapeutic effects of ACE inhibitors are partially mediated by kinins via release of NO, while drugs that activate the angiotensin type 2 receptor act in part via kinins and NO. Thus kinins play an important role in regulation of cardiovascular and renal function as well as many of the beneficial effects of ACE inhibitors and ARBs on target organ damage in hypertension. PMID:23737209

Rhaleb, Nour-Eddine; Yang, Xiao-Ping; Carretero, Oscar A

2011-04-01

213

Cardiovascular risk factors and cardiovascular diseases in patients with moderate to severe psoriasis under systemic treatment. PSO-RISK, descriptive study.  

PubMed

Background: The prevalence of cardiovascular risk factors (CVRF) in psoriasis has not been studied in large Spanish samples. Objective: To assess the prevalence of major CVRFs in psoriasis patients requiring systemic treatments. Material and Methods: Cross-sectional study in psoriasis patients from 33 hospital dermatology offices throughout Spain. Blood pressure (BP) was measured and a fasting lab test was performed. Each CVRF was diagnosed according to the recommendations of international societies. Results: In 368 patients (mean age 48 years old, 36% women), 80.2% had at least one CVRF. The prevalence of each CVRF was similar in men and women and slightly higher in patients with psoriatic arthritis and in patients with a history of more severe disease. The percentage of patients treated with drugs to control CVRF was low (?50% of those with each CVRF). A total of 20.7% had experienced some cardiovascular disease (CVD) episode. Conclusion: The prevalence of CVRF was high, higher than in the general Spanish population, and 20% had already suffered CVD. However, the percentage with drug treatments for CVRF was low. PMID:25333326

Vanaclocha, Francisco; Belinchón, Isabel; Sánchez-Carazo, José L; Rivera, Raquel; Carrascosa, José M; Cea-Calvo, Luis; Juliá, Berta; Puig, Lluěs

2014-10-21

214

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

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

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

2009-01-01

215

A practical introduction to the hemodynamic analysis of the cardiovascular system with 4D Flow MRI.  

PubMed

The 4D Flow MRI technique provides a three-dimensional representation of blood flow over time, making it possible to evaluate the hemodynamics of the cardiovascular system both qualitatively and quantitatively. In this article, we describe the application of the 4D Flow technique in a 3T scanner; in addition to the technical parameters, we discuss the advantages and limitations of the technique and its possible clinical applications. We used 4D Flow MRI to study different body areas (chest, abdomen, neck, and head) in 10 volunteers. We obtained 3D representations of the patterns of flow and quantitative hemodynamic measurements. The technique makes it possible to evaluate the pattern of blood flow in large and midsize vessels without the need for exogenous contrast agents. PMID:25447368

Pineda Zapata, J A; Delgado de Bedout, J A; Rascovsky Ramírez, S; Bustamante, C; Mesa, S; Calvo Betancur, V D

2014-01-01

216

Fabrication of polyurethane and polyurethane based composite fibres by the electrospinning technique for soft tissue engineering of cardiovascular system.  

PubMed

Electrospinning is a unique technique, which provides forming of polymeric scaffolds for soft tissue engineering, which include tissue scaffolds for soft tissues of the cardiovascular system. Such artificial soft tissues of the cardiovascular system may possess mechanical properties comparable to native vascular tissues. Electrospinning technique gives the opportunity to form fibres with nm- to ?m-scale in diameter. The arrangement of obtained fibres and their surface determine the biocompatibility of the scaffolds. Polyurethanes (PUs) are being commonly used as a prosthesis of cardiovascular soft tissues due to their excellent biocompatibility, non-toxicity, elasticity and mechanical properties. PUs also possess fine spinning properties. The combination of a variety of PU properties with an electrospinning technique, conducted at the well tailored conditions, gives unlimited possibilities of forming novel polyurethane materials suitable for soft tissue scaffolds applied in cardiovascular tissue engineering. This paper can help researches to gain more widespread and deeper understanding of designing electrospinable PU materials, which may be used as cardiovascular soft tissue scaffolds. In this paper we focus on reagents used in PU synthesis designed to increase PU biocompatibility (polyols) and biodegradability (isocyanates). We also describe suggested surface modifications of electrospun PUs, and the direct influence of surface wettability on providing enhanced biocompatibility of scaffolds. We indicate a great influence of electrospinning parameters (voltage, flow rate, working distance) and used solvents (mostly DMF, THF and HFIP) on fibre alignment and diameter - what impacts the biocompatibility and hemocompatibility of such electrospun PU scaffolds. Moreover, we present PU modifications with natural polymers with novel approach applied in electrospinning of PU scaffolds. This work may contribute with further developing of novel electrospun PUs, which may be applied as soft tissue scaffolds of the cardiovascular system. PMID:25491973

Kucinska-Lipka, J; Gubanska, I; Janik, H; Sienkiewicz, M

2015-01-01

217

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

NASA Astrophysics Data System (ADS)

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 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.

Imanaka-Yoshida, Kyoko; Aoki, Hiroki

2014-07-01

218

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

PubMed Central

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

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

219

SUBCHRONIC PULMONARY PATHOLOGY, IRON-OVERLOAD AND TRANSCRIPTIONAL ACTIVITY AFTER LIBBY AMPHIBOLE EXPOSURE IN RAT MODELS OF CARDIOVASCULAR DISEASE  

EPA Science Inventory

Background: Surface-available iron (Fe) is proposed to contribute to asbestos-induced toxicity through the production of reactive oxygen species.Objective: Our goal was to evaluate the hypothesis that rat models of cardiovascular disease with coexistent Fe overload would be incre...

220

Chronic inhalation of carbon monoxide: Effects on the respiratory and cardiovascular system at doses corresponding to tobacco smoking  

Microsoft Academic Search

Carbon monoxide (CO) is a dangerous poison in high concentrations, but the long-term effects of low doses of CO, as in the gaseous component of tobacco smoke, are not well known. The aims of our study were to evaluate the long-term effects of inhaled CO on the respiratory and cardiovascular system at doses corresponding to tobacco smoking and its effect

Sveinung Sřrhaug; Sigurd Steinshamn; Odd G. Nilsen; Helge L. Waldum

2006-01-01

221

Renal and Cardiovascular Responses to Water Immersion in Essential Hypertension: Is There a Role for the Opioidergic System?  

Microsoft Academic Search

Our study aimed at elucidating the effects of acute central hypervolemia induced by water immersion (WI) on renal hemodynamics, hormonal responses and on cardiovascular control in hypertensive patients, as well as at evaluating the possible role of the opioidergic system (OS) in determining these effects. Thirteen essential hypertensives were studied for 2 h before and for 2 h during WI.

Paolo Coruzzi; Gianfranco Parati; Lorenzo Brambilla; Valerio Brambilla; Massimo Gualerzi; Almerico Novarini; Giuseppe Mancia; Paolo Castiglioni; Marco Di Rienzo

2003-01-01

222

738. Optimizing a Lentiviral Vector System for Efficient Transduction of Primary Rat Cardiovascular Cells In Vitro  

Microsoft Academic Search

Cardiovascular disease (CVD) is the number one cause of mortality in the United States. However, little progress has been made in the development of effective gene therapy treatments for cardiovascular pathologies. Recently, lentiviral vectors based on HIV-1 have been developed and optimized, and have ideal characteristics for gene therapy applications to treat CVD, particularly in myocardium and vascular smooth muscle.

Jody R. Arsenault; Naoichiro Hattan; William M. Chilian; Kurt J. Varner; Frank Park

2004-01-01

223

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

PubMed Central

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

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

224

The role of the cholinergic system of the bed nucleus of the stria terminalis on the cardiovascular responses and the baroreflex modulation in rats  

Microsoft Academic Search

The bed nucleus of the stria terminalis (BST) is a limbic structure involved in cardiovascular regulation and modulation of responses to stress. The BST contains high levels of muscarinic receptors. This study was performed to find the effects of cholinergic system of the BST on the cardiovascular regulation and the baroreflex modulation in rats. Drugs (50–100nl) were microinjected into the

Ali Nasimi; Masoumeh Hatam

2011-01-01

225

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

PubMed Central

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

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

2013-01-01

226

'Decision support system (DSS) for prevention of cardiovascular disease (CVD) among hypertensive (HTN) patients in Andhra Pradesh, India' - a cluster randomised community intervention trial  

E-print Network

AbstractBackgroundVery few studies having decision support systems as an intervention report on patient outcomes for cardiovascular disease in the Western world. The potential role of decision support system for the management of blood pressure...

Anchala, Raghupathy; Pant, Hira; Prabhakaran, Dorairaj; Franco, Oscar H

2012-05-31

227

Using a Telemedicine System to Decrease Cardiovascular Disease Risk in an Underserved Population: Design, Use, and Interim Results  

Microsoft Academic Search

Cardiovascular disease is the leading cause of morbidity and mortality in the USA. Disease management programs, while successful, are intensive and expensive. Follow-up is often inadequate, incomplete, and inconsistent. To address these problems, we developed an Internet- Telemedicine system. Patients send\\/receive data to\\/from their care provider via the Internet. The system optimizes function and minimizes cost (all hardware is off

William P. Santamore; Carol J. Homko; Abul Kashem; Timothy R. McConnell; A. A. Bove

2007-01-01

228

Cardiovascular imaging payment and reimbursement systems: understanding the past and present in order to guide the future.  

PubMed

Uncertainty regarding the future of cardiovascular (CV) services and reimbursement systems in this era of rapid change in health care delivery may lead to further confusion among imagers. This article provides a brief history of national payment and reimbursement systems, and discusses potential changes that will impact CV imaging in the coming years. Data over the last decade are presented on payment and utilization of services to demonstrate the impact of reimbursement reforms and education on imaging use. PMID:24651111

Ferrari, Victor A; Whitman, Brian; Blankenship, James C; Budoff, Matthew J; Costa, Marco; Weissman, Neil J; Cerqueira, Manuel D

2014-03-01

229

SUSCEPTIBILITY TO OZONE-INDUCED INJURY AND ANTIOXIDANT COMPENSATION IN RAT MODELS OF CARDIOVASCULAR DISEASE  

EPA Science Inventory

Increased oxidative stress and compromised antioxidant status are common pathologic factors of cardiovascular diseases (CVD). It is hypothesized that individuals with chronic CVD are more susceptible to environmental exposures due to underlying oxidative stress. To determine the ...

230

ALTERATIONS OF FE HOMEOSTASIS IN RAT CARDIOVASCULAR DISEASE MODELS AND ITS CONTRIBUTION TO CARDIOPULMONARY TOXICITY  

EPA Science Inventory

Introduction: Fe homeostasis can be disrupted in human cardiovascular diseases (CVD). We addressed how dysregulation of Fe homeostasis affected the pulmonary inflammation/oxidative stress response and disease progression after exposure to Libby amphibole (LA), an asbestifonn mine...

231

Cardiovascular responses to external counterpulsation: a computer simulation  

Microsoft Academic Search

A mathematical model of the human cardiovascular system is presented which includes a simulation of cardiac assistance by\\u000a external counterpulsation. The model was established to study the effects of external counterpulsation on cardiovascular haemodynamics.\\u000a The closed simulation includes both the left and the right heart and the pulmonary circulation. The model is able to provide\\u000a data for the behaviour of

J. Bai; K. Ying; D. Jaron

1992-01-01

232

Salud para su Corazón: a community-based Latino cardiovascular disease prevention and outreach model.  

PubMed

Cardiovascular disease (CVD) is the leading cause of death for Latinos living in the United States. This population is generally unaware of important lifestyle or behavioral changes that can prevent CVD. The National Heart, Lung, and Blood Institute (NHLBI) designed and implemented Salud para su Corazón (Health for Your Heart), a culturally appropriate, community-based, theory-driven intervention model. NHLBI's goals were: (1) to design an intervention model appropriate to Latino populations; (2) to pilot test the model in a specific community with the objectives of increasing awareness about heart disease, raising knowledge about CVD prevention, and promoting heart-healthy lifestyles; and (3) to disseminate the model and the materials developed to other communities with similar needs. An agency-community partnership, under the leadership of the Community Alliance for Heart Health, guided all stages of the community intervention project. The multimedia bilingual community intervention included television telenovela format public service announcements (PSAs), radio programs, brochures, recipe booklets, charlas, a promotores training manual, and motivational videos. An evaluation survey assessed the impact of the intervention. A pre-post intervention survey was conducted with more than 300 participants, and results showed that the respondents were substantially more aware of risk factors for CVD, and had greatly increased their knowledge of ways to prevent heart disease. Dissemination efforts have resulted in numerous requests by health organizations, universities, and health maintenance organizations (HMOs) for educational materials and communication strategies produced by Salud para su Corazón. In addition, Univision, the largest Spanish-language broadcast television network, is airing the initiative's PSAs. Also, training seminars for promotores are being conducted in different regions of the United States, and several locations are planning to replicate this study. PMID:10555925

Alcalay, R; Alvarado, M; Balcazar, H; Newman, E; Huerta, E

1999-10-01

233

Image-Based Computational Fluid Dynamics in Blood Vessel Models: Toward Developing a Prognostic Tool to Assess Cardiovascular Function Changes in Prolonged Space Flights  

NASA Technical Reports Server (NTRS)

One of NASA's objectives is to be able to perform a complete, pre-flight, evaluation of cardiovascular changes in astronauts scheduled for prolonged space missions. Computational fluid dynamics (CFD) has shown promise as a method for estimating cardiovascular function during reduced gravity conditions. For this purpose, MRI can provide geometrical information, to reconstruct vessel geometries, and measure all spatial velocity components, providing location specific boundary conditions. The objective of this study was to investigate the reliability of MRI-based model reconstruction and measured boundary conditions for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T Siemens MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction (slice thickness 3 and 5 mm; pixel size 1x1 and 0.5x0.5 square millimeters). Velocity acquisitions provided measured inlet boundary conditions and localized three-directional steady-flow velocity data (0.7-3.0 L/min). The vessel walls were isolated using NIH provided software (ImageJ) and lofted to form the geometric surface. Constructed and idealized geometries were imported into a commercial CFD code for meshing and simulation. 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 less than 10% differences in the local velocity values. CFD results on models reconstructed from different MRI resolution settings showed insignificant differences (less than 5%). This study illustrated, quantitatively, that reliable CFD simulations can be performed with MRI reconstructed models and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system alteration during space travel is feasible.

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

2004-01-01

234

The Effect of Tobacco Control Measures during a Period of Rising Cardiovascular Disease Risk in India: A Mathematical Model of Myocardial Infarction and Stroke  

PubMed Central

Background We simulated tobacco control and pharmacological strategies for preventing cardiovascular deaths in India, the country that is expected to experience more cardiovascular deaths than any other over the next decade. Methods and Findings A microsimulation model was developed to quantify the differential effects of various tobacco control measures and pharmacological therapies on myocardial infarction and stroke deaths stratified by age, gender, and urban/rural status for 2013 to 2022. The model incorporated population-representative data from India on multiple risk factors that affect myocardial infarction and stroke mortality, including hypertension, hyperlipidemia, diabetes, coronary heart disease, and cerebrovascular disease. We also included data from India on cigarette smoking, bidi smoking, chewing tobacco, and secondhand smoke. According to the model's results, smoke-free legislation and tobacco taxation would likely be the most effective strategy among a menu of tobacco control strategies (including, as well, brief cessation advice by health care providers, mass media campaigns, and an advertising ban) for reducing myocardial infarction and stroke deaths over the next decade, while cessation advice would be expected to be the least effective strategy at the population level. In combination, these tobacco control interventions could avert 25% of myocardial infarctions and strokes (95% CI: 17%–34%) if the effects of the interventions are additive. These effects are substantially larger than would be achieved through aspirin, antihypertensive, and statin therapy under most scenarios, because of limited treatment access and adherence; nevertheless, the impacts of tobacco control policies and pharmacological interventions appear to be markedly synergistic, averting up to one-third of deaths from myocardial infarction and stroke among 20- to 79-y-olds over the next 10 y. Pharmacological therapies could also be considerably more potent with further health system improvements. Conclusions Smoke-free laws and substantially increased tobacco taxation appear to be markedly potent population measures to avert future cardiovascular deaths in India. Despite the rise in co-morbid cardiovascular disease risk factors like hyperlipidemia and hypertension in low- and middle-income countries, tobacco control is likely to remain a highly effective strategy to reduce cardiovascular deaths. Please see later in the article for the Editors' Summary PMID:23874160

Basu, Sanjay; Glantz, Stanton; Bitton, Asaf; Millett, Christopher

2013-01-01

235

Defining optimal research study design for cardiovascular imaging using computed tomography angiography as a model.  

PubMed

Patients, physicians, and payers are facing a significant increase in cardiovascular (CV) imaging use, resulting in skyrocketing societal costs, without clear improvement in patient outcomes. The need for studies evaluating the effects of CV imaging that assess appropriate end points is critical to address continued concerns over the lack of well-designed clinical studies. Thus, the investigators propose a framework, using computed tomographic angiography as a model, that should be considered in the optimal design of future imaging research and would potentially provide payers with data to make appropriate reimbursement decisions. The inclusion of risk stratification, randomization, multiple-site participation, and multigeography site enrollment are key elements in the construction of such studies. Meaningful end points with regard to operating characteristics, downstream testing, CV event rates, outcomes, and costs are essential to appropriately evaluate any new imaging technology. Only once better level evidence is formed to support CV imaging can the central issues of quality and appropriateness of CV imaging truly be evaluated. If the CV community does not embrace this type of scientific evaluation of CV imaging modalities and fails to adequately identify the value in these techniques, it may ultimately lose the ability to use them to provide optimal care to its patients. PMID:18805127

Shah, Bimal R; Patel, Manesh R; Peterson, Eric D; Douglas, Pamela S

2008-10-01

236

Spectrofluorimetric methods of stability-indicating assay of certain drugs affecting the cardiovascular system  

NASA Astrophysics Data System (ADS)

Two stability-indicating spectrofluorimetric methods have been developed for the determination of ezetimibe and olmesartan medoxomil, drugs affecting the cardiovascular system, and validated in the presence of their degradation products. The first method, for ezetimibe, is based on an oxidative coupling reaction of ezetimibe with 3-methylbenzothiazolin-2-one hydrazone hydrochloride in the presence of cerium (IV) ammonium sulfate in an acidic medium. The quenching effect of ezetimibe on the fluorescence of excess cerous ions is measured at the emission wavelength, ?em, of 345 nm with the excitation wavelength, ?ex, of 296 nm. Factors affecting the reaction were carefully studied and optimized. The second method, for olmesartan medoxomil, is based on measuring the native fluorescence intensity of olmesartan medoxomil in methanol at ?em = 360 nm with ?ex = 286 nm. Regression plots revealed good linear relationships in the assay limits of 10-120 and 8-112 g/ml for ezetimibe and olmesartan medoxomil, respectively. The validity of the methods was assessed according to the United States Pharmacopeya guidelines. Statistical analysis of the results exposed good Student's t-test and F-ratio values. The introduced methods were successfully applied to the analysis of ezetimibe and olmesartan medoxomil in drug substances and drug products as well as in the presence of their degradation products.

Moussa, B. A.; Mohamed, M. F.; Youssef, N. F.

2011-01-01

237

Development of Anatomophysiologic Knowledge Regarding the Cardiovascular System: From Egyptians to Harvey.  

PubMed

Our knowledge regarding the anatomophysiology of the cardiovascular system (CVS) has progressed since the fourth millennium BC. In Egypt (3500 BC), it was believed that a set of channels are interconnected to the heart, transporting air, urine, air, blood, and the soul. One thousand years later, the heart was established as the center of the CVS by the Hippocratic Corpus in the medical school of Kos, and some of the CVS anatomical characteristics were defined. The CVS was known to transport blood via the right ventricle through veins and the pneuma via the left ventricle through arteries. Two hundred years later, in Alexandria, following the development of human anatomical dissection, Herophilus discovered that arteries were 6 times thicker than veins, and Erasistratus described the semilunar valves, emphasizing that arteries were filled with blood when ventricles were empty. Further, 200 years later, Galen demonstrated that arteries contained blood and not air. With the decline of the Roman Empire, Greco-Roman medical knowledge about the CVS was preserved in Persia, and later in Islam where, Ibn Nafis inaccurately described pulmonary circulation. The resurgence of dissection of the human body in Europe in the 14th century was associated with the revival of the knowledge pertaining to the CVS. The main findings were the description of pulmonary circulation by Servetus, the anatomical discoveries of Vesalius, the demonstration of pulmonary circulation by Colombo, and the discovery of valves in veins by Fabricius. Following these developments, Harvey described blood circulation. PMID:25317863

Bestetti, Reinaldo Bulgarelli; Restini, Carolina Baraldi A; Couto, Lucélio B

2014-10-10

238

Store-operated cation channels in the heart and cells of the cardiovascular system.  

PubMed

In many nonexcitable cells, activation of phospholipase C (PLC)-linked receptors results in a release of Ca(2+) from intracellular stores followed by a transmembrane Ca(2+) entry. This Ca(2+) entry underlies the sustained phase of [Ca(2+)](i) increase, is important for various cellular functions including gene expression, secretion and cell proliferation, and is supported by agonist-activated Ca(2+)-permeable ion channels. Ca(2+)-permeable channels which are activated by store depletion and which are therefore referred to as store- operated channels or SOCs form a major pathway for agonist-induced Ca(2+) influx. So far, the molecular structures of these channels have not been identified. Potential candidates are encoded by members of the TRP family, a class of ion channels initially discovered in Drosophila and involved in the PLC-dependent transduction of visual stimuli. Here, we review recent evidence that agonist-induced Ca(2+) influx and especially SOCs are present in different cell types of the heart and of the cardiovascular system and compare these findings with the possible functions and tissue-specific expression of mammalian TRP proteins. PMID:10575202

Freichel, M; Schweig, U; Stauffenberger, S; Freise, D; Schorb, W; Flockerzi, V

1999-01-01

239

Development of Anatomophysiologic Knowledge Regarding the Cardiovascular System: From Egyptians to Harvey  

PubMed Central

Our knowledge regarding the anatomophysiology of the cardiovascular system (CVS) has progressed since the fourth millennium BC. In Egypt (3500 BC), it was believed that a set of channels are interconnected to the heart, transporting air, urine, air, blood, and the soul. One thousand years later, the heart was established as the center of the CVS by the Hippocratic Corpus in the medical school of Kos, and some of the CVS anatomical characteristics were defined. The CVS was known to transport blood via the right ventricle through veins and the pneuma via the left ventricle through arteries. Two hundred years later, in Alexandria, following the development of human anatomical dissection, Herophilus discovered that arteries were 6 times thicker than veins, and Erasistratus described the semilunar valves, emphasizing that arteries were filled with blood when ventricles were empty. Further, 200 years later, Galen demonstrated that arteries contained blood and not air. With the decline of the Roman Empire, Greco-Roman medical knowledge about the CVS was preserved in Persia, and later in Islam where, Ibn Nafis inaccurately described pulmonary circulation. The resurgence of dissection of the human body in Europe in the 14th century was associated with the revival of the knowledge pertaining to the CVS. The main findings were the description of pulmonary circulation by Servetus, the anatomical discoveries of Vesalius, the demonstration of pulmonary circulation by Colombo, and the discovery of valves in veins by Fabricius. Following these developments, Harvey described blood circulation. PMID:25590934

Bestetti, Reinaldo Bulgarelli; Restini, Carolina Baraldi A.; Couto, Lucélio B.

2014-01-01

240

Impact of Bisphenol A on the Cardiovascular System — Epidemiological and Experimental Evidence and Molecular Mechanisms  

PubMed Central

Bisphenol A (BPA) is a ubiquitous plasticizing agent used in the manufacturing of polycarbonate plastics and epoxy resins. There is well-documented and broad human exposure to BPA. The potential risk that BPA poses to the human health has attracted much attention from regulatory agencies and the general public, and has been extensively studied. An emerging and rapidly growing area in the study of BPA’s toxicity is its impact on the cardiovascular (CV) system. Recent epidemiological studies have shown that higher urinary BPA concentration in humans is associated with various types of CV diseases, including angina, hypertension, heart attack and coronary and peripheral arterial disease. Experimental studies have demonstrated that acute BPA exposure promotes the development of arrhythmias in female rodent hearts. Chronic exposure to BPA has been shown to result in cardiac remodeling, atherosclerosis, and altered blood pressure in rodents. The underlying mechanisms may involve alteration of cardiac Ca2+ handling, ion channel inhibition/activation, oxidative stress, and genome/transcriptome modifications. In this review, we discuss these recent findings that point to the potential CV toxicity of BPA, and highlight the knowledge gaps in this growing research area. PMID:25153468

Gao, Xiaoqian; Wang, Hong-Sheng

2014-01-01

241

Development of anatomophysiologic knowledge regarding the cardiovascular system: from egyptians to harvey.  

PubMed

Our knowledge regarding the anatomophysiology of the cardiovascular system (CVS) has progressed since the fourth millennium BC. In Egypt (3500 BC), it was believed that a set of channels are interconnected to the heart, transporting air, urine, air, blood, and the soul. One thousand years later, the heart was established as the center of the CVS by the Hippocratic Corpus in the medical school of Kos, and some of the CVS anatomical characteristics were defined. The CVS was known to transport blood via the right ventricle through veins and the pneuma via the left ventricle through arteries. Two hundred years later, in Alexandria, following the development of human anatomical dissection, Herophilus discovered that arteries were 6 times thicker than veins, and Erasistratus described the semilunar valves, emphasizing that arteries were filled with blood when ventricles were empty. Further, 200 years later, Galen demonstrated that arteries contained blood and not air. With the decline of the Roman Empire, Greco-Roman medical knowledge about the CVS was preserved in Persia, and later in Islam where, Ibn Nafis inaccurately described pulmonary circulation. The resurgence of dissection of the human body in Europe in the 14th century was associated with the revival of the knowledge pertaining to the CVS. The main findings were the description of pulmonary circulation by Servetus, the anatomical discoveries of Vesalius, the demonstration of pulmonary circulation by Colombo, and the discovery of valves in veins by Fabricius. Following these developments, Harvey described blood circulation. PMID:25590934

Bestetti, Reinaldo Bulgarelli; Restini, Carolina Baraldi A; Couto, Lucélio B

2014-12-01

242

Impact of bisphenol a on the cardiovascular system - epidemiological and experimental evidence and molecular mechanisms.  

PubMed

Bisphenol A (BPA) is a ubiquitous plasticizing agent used in the manufacturing of polycarbonate plastics and epoxy resins. There is well-documented and broad human exposure to BPA. The potential risk that BPA poses to the human health has attracted much attention from regulatory agencies and the general public, and has been extensively studied. An emerging and rapidly growing area in the study of BPA's toxicity is its impact on the cardiovascular (CV) system. Recent epidemiological studies have shown that higher urinary BPA concentration in humans is associated with various types of CV diseases, including angina, hypertension, heart attack and coronary and peripheral arterial disease. Experimental studies have demonstrated that acute BPA exposure promotes the development of arrhythmias in female rodent hearts. Chronic exposure to BPA has been shown to result in cardiac remodeling, atherosclerosis, and altered blood pressure in rodents. The underlying mechanisms may involve alteration of cardiac Ca2+ handling, ion channel inhibition/activation, oxidative stress, and genome/transcriptome modifications. In this review, we discuss these recent findings that point to the potential CV toxicity of BPA, and highlight the knowledge gaps in this growing research area. PMID:25153468

Gao, Xiaoqian; Wang, Hong-Sheng

2014-08-01

243

Does early intensive multifactorial therapy reduce modelled cardiovascular risk in individuals with screen-detected diabetes? Results from the ADDITION-Europe cluster randomized trial  

PubMed Central

Aims Little is known about the long-term effects of intensive multifactorial treatment early in the diabetes disease trajectory. In the absence of long-term data on hard outcomes, we described change in 10-year modelled cardiovascular risk in the 5 years following diagnosis, and quantified the impact of intensive treatment on 10-year modelled cardiovascular risk at 5 years. Methods In a pragmatic, cluster-randomized, parallel-group trial in Denmark, the Netherlands and the UK, 3057 people with screen-detected Type 2 diabetes were randomized by general practice to receive (1) routine care of diabetes according to national guidelines (1379 patients) or (2) intensive multifactorial target-driven management (1678 patients). Ten-year modelled cardiovascular disease risk was calculated at baseline and 5 years using the UK Prospective Diabetes Study Risk Engine (version 3?). Results Among 2101 individuals with complete data at follow up (73.4%), 10-year modelled cardiovascular disease risk was 27.3% (sd 13.9) at baseline and 21.3% (sd 13.8) at 5-year follow-up (intensive treatment group difference –6.9, sd 9.0; routine care group difference –5.0, sd 12.2). Modelled 10-year cardiovascular disease risk was lower in the intensive treatment group compared with the routine care group at 5 years, after adjustment for baseline cardiovascular disease risk and clustering (–2.0; 95% CI –3.1 to –0.9). Conclusions Despite increasing age and diabetes duration, there was a decline in modelled cardiovascular disease risk in the 5 years following diagnosis. Compared with routine care, 10-year modelled cardiovascular disease risk was lower in the intensive treatment group at 5 years. Our results suggest that patients benefit from intensive treatment early in the diabetes disease trajectory, where the rate of cardiovascular disease risk progression may be slowed. PMID:24533664

Black, J A; Sharp, S J; Wareham, N J; Sandbćk, A; Rutten, G E H M; Lauritzen, T; Khunti, K; Davies, M J; Borch-Johnsen, K; Griffin, S J; Simmons, R K

2014-01-01

244

Cardiovascular Research The University of Birmingham  

E-print Network

systemic cardiovascular and respiratory homeostasis in health and disease. The group consists of basic in diseases of metabolism including diabetes and metabolic syndrome; the impact upon cardiovascular regulationCardiovascular Research The University of Birmingham #12;2 Cardiovascular Sciences in Birmingham

Birmingham, University of

245

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

PubMed

The purpose of this study is to evaluate cardiovascular risk assessment at a Canadian rheumatology center and describe the cardiovascular risk of inflammatory arthritis (IA) and systemic lupus erythematosus (SLE) patients using the Framingham risk score. A retrospective chart review of 504 patients attending nine rheumatology practices at the University of Alberta Hospital was performed. A pre-specified case report form detailed patient demographics, cardiac risk factors, variables for the Framingham 2008 score, disease activity, and medication use. In this group of 504 patients, 64 (12.7%) had SLE (male (M) to female (F) ratio?=?60:4) and 440 (87.3%) had an IA (M to F ratio?=?117:323). Of the SLE patients, 31 (48.4%) met four or more American College of Rheumatology (ACR) criteria, 33 (51.6%) had less than four ACR criteria. Of the IA patients, 156 (35.5%) were CCP positive and 257 (58.4%) were RF positive. Utilizing the chart data, retrospective Framingham risk scores were calculable for one (1.6%) SLE patient and three (0.68%) IA patients. The most common cardiac risk factors not documented in the medical records of both the SLE and IA patients included: (1) positive family history of MI, (2) diabetes, and (3) lipid status. The blood pressure was more frequently documented in the SLE patients (93.8%) compared to the IA patients (56.1%). While traditional cardiac risk factors only partially contribute to the increased cardiovascular risk in these patients, cardiovascular risk assessment was suboptimally performed amongst a large group of rheumatologists. A dedicated cardiovascular risk reduction clinic for inflammatory rheumatic diseases has been established at this site to fulfill this need and evaluate treatment strategies. PMID:21503617

Keeling, Stephanie O; Teo, Michelle; Fung, Daisy

2011-10-01

246

Criteria for anatomical compatibility of the total artificial heart: computerized three-dimensional modeling of the cardiovascular anatomy.  

PubMed

A quantitative study of cardiovascular anatomy was performed by obtaining three-dimensional reconstructions from regular computed tomography scan images in 15 patients, all candidates for heart transplantation. Volumetric estimates of the cardiovascular structures were obtained from these three-dimensional reconstructions using data directly related to total artificial heart (TAH) implantations. By using computerized three-dimensional modeling of these structures, reproducible measurements of the parameters defining the shape and the anatomical connections of the intrathoracic space available for TAH implantation could be derived. The results are intended to be used for both technical and clinical applications such as computer-assisted drawing of the pericardial cavity and the anatomical connections (useful for improving the design of TAH) and combined statistical calculations (multiple regressions, cluster algorithm) of the measurement results, which will then enable the best selection to be made among two or three TAH models for each patient. PMID:8110069

Chatel, D; Martin-Bouyer, Y; Vicaut, E; Bouchoucha, H; Achard, F; Sablayrolles, J L; Carpentier, A

1993-12-01

247

Physics-driven CFD modeling of complex anatomical cardiovascular flows-a TCPC case study.  

PubMed

Recent developments in medical image acquisition combined with the latest advancements in numerical methods for solving the Navier-Stokes equations have created unprecedented opportunities for developing simple and reliable computational fluid dynamics (CFD) tools for meeting patient-specific surgical planning objectives. However, for CFD to reach its full potential and gain the trust and confidence of medical practitioners, physics-driven numerical modeling is required. This study reports on the experience gained from an ongoing integrated CFD modeling effort aimed at developing an advanced numerical simulation tool capable of accurately predicting flow characteristics in an anatomically correct total cavopulmonary connection (TCPC). An anatomical intra-atrial TCPC model is reconstructed from a stack of magnetic resonance (MR) images acquired in vivo. An exact replica of the computational geometry was built using transparent rapid prototyping. Following the same approach as in earlier studies on idealized models, flow structures, pressure drops, and energy losses were assessed both numerically and experimentally, then compared. Numerical studies were performed with both a first-order accurate commercial software and a recently developed, second-order accurate, in-house flow solver. The commercial CFD model could, with reasonable accuracy, capture global flow quantities of interest such as control volume power losses and pressure drops and time-averaged flow patterns. However, for steady inflow conditions, both flow visualization experiments and particle image velocimetry (PIV) measurements revealed unsteady, complex, and highly 3D flow structures, which could not be captured by this numerical model with the available computational resources and additional modeling efforts that are described. Preliminary time-accurate computations with the in-house flow solver were shown to capture for the first time these complex flow features and yielded solutions in good agreement with the experimental observations. Flow fields obtained were similar for the studied total cardiac output range (1-3 1/min); however hydrodynamic power loss increased dramatically with increasing cardiac output, suggesting significant energy demand at exercise conditions. The simulation of cardiovascular flows poses a formidable challenge to even the most advanced CFD tools currently available. A successful prediction requires a two-pronged, physics-based approach, which integrates high-resolution CFD tools and high-resolution laboratory measurements. PMID:15868719

Pekkan, Kerem; de Zélicourt, Diane; Ge, Liang; Sotiropoulos, Fotis; Frakes, David; Fogel, Mark A; Yoganathan, Ajit P

2005-03-01

248

Characteristics and popular topics of latest researches into the effects of air particulate matter on cardiovascular system by bibliometric analysis.  

PubMed

In recent years, many epidemiological and toxicological studies have investigated the adverse effects of air particulate matter (PM) on the cardiovascular system. However, it is difficult for the researchers to have a timely and effective overall command of the latest characteristics and popular topics in such a wide field. Different from the previous reviews, in which the research characteristics and trends are empirically concluded by experts, we try to have a comprehensive evaluation of the above topics for the first time by bibliometric analysis, a quantitative tool in information exploration. This study aims to introduce the bibliometric method into the field of PM and cardiovascular system. The articles were selected by searching PubMed/MEDLINE (from 2007 to 2012) using Medical Subject Headings (MeSH) terms "particulate matter" and "cardiovascular system". A total of 935 eligible articles and 1895 MeSH terms were retrieved and processed by the software Thomson Data Analyzer (TDA). The bibliographic information and the MeSH terms of these articles were classified and analyzed to summarize the research characteristics. The top 200 high-frequency MeSH terms (the cumulative frequency percentage was 74.2%) were clustered for popular-topic conclusion. We summarized the characteristics of published articles, of researcher collaborations and of the contents. Ten clusters of MeSH terms are presented. Six popular topics are concluded and elaborated for reference. Our study presents an overview of the characteristics and popular topics in the field of PM and cardiovascular system in the past five years by bibliometric tools, which may provide a new perspective for future researchers. PMID:23480197

Jia, Xiaofeng; Guo, Xinbiao; Li, Haicun; An, Xinying; Zhao, Yingguang

2013-03-01

249

Protein Biomarkers of New-Onset Cardiovascular Disease: A Prospective Study from the Systems Approach to Biomarker Research in Cardiovascular Disease (SABRe CVD) Initiative  

PubMed Central

Objective Incorporation of novel plasma protein biomarkers may improve current models for prediction of atherosclerotic cardiovascular disease (ASCVD) risk. Approach and Results We utilized discovery mass spectrometry (MS) to determine plasma concentrations of 861 proteins in 135 myocardial infarction (MI) cases and 135 matched controls. We then measured 59markers by targeted MS in 336 ASCVD case-control pairs. Associations with MI or ASCVD were tested in single marker and multimarker analyses adjusted for established ASCVD risk factors. Twelve single markers from discovery MS were associated with MI incidence (at p<0.01) adjusting for clinical risk factors. Seven proteins in aggregate (cyclophilin A, CD5 antigen-like, cell surface glycoprotein MUC18, collagen-alpha 1 [XVIII] chain, salivary alpha-amylase 1, C-reactive protein, and multimerin-2) were highly associated with MI (p<0.0001) and significantly improved its prediction compared to a model with clinical risk factors alone (C-statistic of 0.71 vs. 0.84). Through targeted MS, twelve single proteins were predictors of ASCVD (at p<0.05) after adjusting for established risk factors. In multimarker analyses, four proteins in combination (alpha-1-acid glycoprotein 1, paraoxonase 1, tetranectin, and CD5 antigen-like, predicted incident ASCVD (p<0.0001) and moderately improved the C-statistic from the model with clinical covariates alone (C-statistic of 0.69 vs. 0.73). Conclusions Proteomics profiling identified single and multimarker protein panels that are associated with new onset ASCVD and may lead to a better understanding of underlying disease mechanisms. Our findings include many novel protein biomarkers that, if externally validated, may improve risk assessment for MI and ASCVD. PMID:24526693

Yin, Xiaoyan; Subramanian, Subha; Hwang, Shih-Jen; O’Donnell, Christopher J.; Fox, Caroline S.; Courchesne, Paul; Muntendam, Pieter; Adourian, Aram; Juhasz, Peter; Larson, Martin G.; Levy, Daniel

2014-01-01

250

Alterations in the Coagulation System of Active Smokers from the Ludwigshafen Risk and Cardiovascular Health (LURIC) Study.  

PubMed

Smoking is an important and preventable risk factor of cardiovascular diseases with effects on blood coagulation. Our aim was to analyze the influence of smoking on coagulation parameters. Concentrations or activities of blood coagulation factors were compared in 777 active smokers and 1,178 lifetime non-smokers of the Ludwigshafen Risk and Cardiovascular Health (LURIC) study. The association with mortality was examined using Cox regression. The findings show that AS had a tendency toward thrombosis. They displayed significantly higher values for fibrinogen, soluble fibrinogen, factor XIII, and tissue factor pathway inhibitor; whereas FVII, FVIII, FXII, von Willebrand factor (vWF), and thrombomodulin were decreased. The Cox regression analysis showed fibrinogen, FVIII, vWF, thrombomodulin, and tissue factor pathway inhibitor to be independent risk factors for mortality in active smokers with hazard ratios of 1.16 (95 % CI: 1.02-1.31), 1.40 (1.22-1.59), 1.37 (1.22-1.56), 1.19 (1.07-1.31), and 1.22 (1.06-1.40) per increase of one standard deviation. We conclude that active smokers have an increased thrombogenic potential associated with significant changes in the coagulation system. Individual parameters of the coagulation system are independent predictors of mortality. Therefore, parameters of the coagulation system, apart from other risk factors for cardiovascular disease (e.g., lipids or life-style) should be determined for risk prediction in active smokers. PMID:25300683

Delgado, G; Siekmeier, R; Grammer, T B; Boehm, B O; März, W; Kleber, M E

2015-01-01

251

The effect of initial treatment of periodontitis on systemic markers of inflammation and cardiovascular risk: a randomized controlled trial.  

PubMed

Observational studies indicate that chronic periodontal disease is associated with adverse cardiovascular outcomes. The aim of this study was to determine whether initial periodontal treatment has a beneficial effect on systemic markers of inflammation and cardiovascular risk. One hundred and thirty-six adults with chronic periodontitis were allocated to either intervention or control groups in a 3-month randomized controlled intervention study. The intervention group received initial periodontal treatment, whereas the control group did not receive that treatment until after the study. Blood levels of cardiovascular risk factors, and of hematological, inflammatory, and metabolic markers, were measured at the beginning and the end of the study, and differences were calculated. Fibrinogen level was the primary outcome measure. Data for 61 persons in the intervention group and for 64 persons in the control group were available for statistical analysis. Compared with the control group, the intervention group showed a non-significant trend for a lower fibrinogen level. Significant increases in hemoglobin and hematocrit were seen after treatment, showing that initial periodontal treatment, a relatively simple and cost-effective intervention, has systemic effects. PMID:20662907

Taylor, Barbara; Tofler, Geoffrey; Morel-Kopp, Marie-Christine; Carey, Helen; Carter, Torren; Elliott, Margaret; Dailey, Colette; Villata, Luke; Ward, Christopher; Woodward, Mark; Schenck, Karl

2010-08-01

252

Human postmortem device retrieval and analysis--orthopaedic, cardiovascular, and dental systems.  

PubMed

On the basis of decades of analyzing implant devices, tissues, and clinical records from revision surgical explants (called device failure), studies now include postmortem donors and in situ conditions (called success). A key issue has been information exchange from an interdisciplinary team where basic physical and biological studies complement details of the clinical conditions for each device. Overall, the summary information has shown that most revisions were based on factors associated with the patient health, disease, and compliance, with few outcomes directly correlated with technology and device-specific factors. However, because of the large numbers of devices implanted annually (millions), any sampling that reveals adverse circumstances could result in a high level of importance and the need for additional studies of this type. Experience from prior retrieval and analysis demonstrates significant value where peer reviewed results from investigations have altered the discipline and have improved the quality and longevity of health care associated with implanted devices. This report summarizes completed and ongoing studies of cardiovascular, dental, and orthopaedic systems. Endovascular stents from autopsies showed damage including fretting and corrosion from overlapping and intersecting conditions, plus some corrosion and element transfers to tissues from individual stents. Studies are proposed to increase numbers to evaluate clinical significance. Dental implants from postmortem donors that functioned more than 10 years provided evaluations of cobalt alloy devices and calcium phosphate bone graft substitutes originally investigated in the 1970s. Tissue integration and stability correlated with data from prior laboratory in vitro and in vivo investigations. Studies of articulation and fixation from orthopaedic total joint arthroplasties showed some limitations related to surface changes of YTZ zirconia, specific damage due to implantation procedures, which led to modified instrumentation and techniques, and several examples of conditions leading to longer-term device-to-bone fixation. These types of multidisciplinary studies are continuing. PMID:21284591

Lemons, J; Brott, B; Eberhardt, A

2010-01-01

253

Adverse pregnancy outcomes and subsequent risk of cardiovascular disease in women with systemic lupus erythematosus  

PubMed Central

Background/objective Patients with systemic lupus erythematosus (SLE) are at increased risk for adverse pregnancy outcomes and cardiovascular disease (CVD). The objective of this exploratory study was to investigate the association between a history of adverse pregnancy outcomes and subsequent risk of subclinical CVD assessed by imaging studies and verified clinical CVD events in 129 women with SLE. Methods The occurrence of adverse pregnancy outcomes, specifically pre-eclampsia, preterm birth and low birth weight was ascertained by questionnaire. Subclinical CVD was assessed by coronary artery calcium (CAC) as measured by electron beam CT and carotid plaque measured by B mode ultrasound. Clinical CVD events were verified by medical record review. Logistic regression was used to estimate the association of pregnancy complications with occurrence of subclinical CVD and clinical CVD with a priori adjustment for age, which is associated with CVD and SLE disease duration as a measure of SLE disease burden. Results Fifty-six women reported at least one pregnancy complication while 73 had none. Twenty-six women had at least one pregnancy complicated by pre-eclampsia and were more likely to have a CAC score greater than or equal to 10 (adjusted OR=3.7; 95% CI 1.2 to 11.9), but the presence of plaque was not associated with this pregnancy complication, OR=1.1, (95% CI 0.4 to 2.8). Low birth weight and preterm birth were not associated with CAC or plaque. Conclusions Patients with SLE with a history of pre-eclampsia had a higher rate of subclinical CVD as measured by CAC score. Future studies are needed to confirm the relationship between adverse pregnancy outcomes and subsequent subclinical CVD and clinical CVD events. PMID:25379191

Lin, Pin; Rhew, Elisa; Ness, Roberta B; Peaceman, Alan; Dyer, Alan; McPherson, David; Kondos, George T; Edmundowicz, Daniel; Sutton-Tyrrell, Kim; Thompson, Trina; Ramsey-Goldman, Rosalind

2014-01-01

254

The effectiveness and cost effectiveness of dark chocolate consumption as prevention therapy in people at high risk of cardiovascular disease: best case scenario analysis using a Markov model  

PubMed Central

Objective To model the long term effectiveness and cost effectiveness of daily dark chocolate consumption in a population with metabolic syndrome at high risk of cardiovascular disease. Design Best case scenario analysis using a Markov model. Setting Australian Diabetes, Obesity and Lifestyle study. Participants 2013 people with hypertension who met the criteria for metabolic syndrome, with no history of cardiovascular disease and not receiving antihypertensive therapy. Main outcome measures Treatment effects associated with dark chocolate consumption derived from published meta-analyses were used to determine the absolute number of cardiovascular events with and without treatment. Costs associated with cardiovascular events and treatments were applied to determine the potential amount of funding required for dark chocolate therapy to be considered cost effective. Results Daily consumption of dark chocolate (polyphenol content equivalent to 100 g of dark chocolate) can reduce cardiovascular events by 85 (95% confidence interval 60 to 105) per 10?000 population treated over 10 years. $A40 (Ł25; €31; $42) could be cost effectively spent per person per year on prevention strategies using dark chocolate. These results assume 100% compliance and represent a best case scenario. Conclusions The blood pressure and cholesterol lowering effects of dark chocolate consumption are beneficial in the prevention of cardiovascular events in a population with metabolic syndrome. Daily dark chocolate consumption could be an effective cardiovascular preventive strategy in this population. PMID:22653982

2012-01-01

255

CARDIOVASCULAR DISEASES, SUSCEPTIBILITY TO OXIDATIVE INJURY AND COMPENSATORY MECHANISMS: INSIGHTS FROM RODENT MODELS  

EPA Science Inventory

Cardiovascular diseases (CVD) are the number one cause for human mortality and nearly 25% of the population develops chronic CVD at an age of 65 years or older. Environmental and genetic interactions govern pathogenesis. Increased oxidative stress and compromised antioxidant stat...

256

Examination of Susceptibility to Libby Amphibole Asbestos-Induced Injury in Rat Models of Cardiovascular Disease  

EPA Science Inventory

Although cardiovascular disease (CVD) is considered a risk factor for the exacerbation of air pollution health effects, no studies have been done assessing the influence of the disease on the development of lung injury induced by asbestos exposure. In this study we examined lung ...

257

TRC210258, a novel TGR5 agonist, reduces glycemic and dyslipidemic cardiovascular risk in animal models of diabesity  

PubMed Central

Background Patients with diabesity have a significantly increased risk of developing cardiovascular disease. Therefore, therapy addressing the multiple metabolic abnormalities linked with diabesity and leading to further reduction of cardiovascular risk is highly desirable. Activation of the TGR5 receptor holds therapeutic potential for diabesity. In the present study, we evaluated the efficacy of TRC210258, a novel TGR5 agonist, in clinically relevant animal models of diabesity. Methods A novel small molecule, TRC210258 (N-(4-chlorophenyl)-2-(4-fluorophenoxy)-N-methylimidazo (1, 2-a) pyrimidine-3-carboxamide), was synthesized. The in vitro TGR5 receptor activation potential of TRC210258 was assessed by cyclic adenosine monophosphate (cAMP) assay and cAMP-responsive element reporter assay using cells overexpressing the human TGR5 receptor. The effect of TRC210258 on glucagon-like peptide-1 release was evaluated in vitro using a human enteroendocrine cell line. The effect of TRC210258 on energy expenditure and glycemic control was evaluated in high-fat diet-induced obese mice. Additionally, the effect of TRC210258 on dyslipidemic parameters was determined in high fat-fed hamsters. Results TRC210258 demonstrated potent TGR5 agonist activity, with enhanced glucagon-like peptide-1 release and energy expenditure. Treatment with TRC210258 resulted in better glycemic control and improved parameters of dyslipidemia such as plasma triglyceride, low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol levels. Treatment with TRC210258 also improved emerging dyslipidemic cardiovascular risk parameters, including remnant cholesterol and triglyceride clearance. Conclusion This study highlights the potential of TRC210258, a novel TGR5 agonist, to improve dyslipidemic cardiovascular risk beyond glycemic control in patients with type 2 diabetes. PMID:24379686

Zambad, Shitalkumar P; Tuli, Davinder; Mathur, Anoop; Ghalsasi, Sameer A; Chaudhary, Anita R; Deshpande, Shailesh; Gupta, Ramesh C; Chauthaiwale, Vijay; Dutt, Chaitanya

2014-01-01

258

Effects of Cold Modality Application With Static and Intermittent Pneumatic Compression on Tissue Temperature and Systemic Cardiovascular Responses  

PubMed Central

Background: In the therapeutic setting, cryotherapy with varying levels of intermittent cyclical compression often replaces an ice bag and elastic wrap. However, little is known about the cardiovascular strain and tissue temperature decreases associated with cooling and intermittent compression. Hypothesis: The authors hypothesized that higher levels of intermittent compression will result in greater reductions of tissue temperature and that all cold modalities will cause acute increases in cardiovascular strain. Design: Experimental crossover repeated measure design. Methods: Ten healthy subjects (23 ± 3 years) volunteered for 4 cryotherapy sessions (30-minute treatments with 30-minute passive recovery). Treatments included ice with elastic wrap and Game Ready (GR) with no, medium (5-50 mmHg), and high compression (5-75 mmHg). Throughout the experiment, oral, skin surface, and intramuscular quadriceps temperatures were measured along with mean arterial pressure, heart rate, rate pressure product, forearm blood flow, and forearm vascular conductance. Results: Mean arterial pressure increased up to 5 minutes (P < 0.05). Forearm blood flow and forearm vascular conductance decreased after baseline (P < 0.05), but there were no differences between treatments. Peak intramuscular changes from baseline were ?14 ± 2°C (ice), ?11 ± 6°C (GRHIGH), ?10 ± 5°C (GRMED), and ?7 ± 3°C (GRNO). Ice cooled the muscle the most, while GR with medium and high compression cooled more than GR without compression (P < 0.05). Conclusions: The application of cold and intermittent pneumatic compression using GR did not produce acute cardiovascular strain that exceeded the strain produced by standard ice bags/elastic wrap treatment. Greater temperature decreases are achieved with medium- and high-pressure settings when using the GR system. Clinical Relevance: Type of cold and amount of compression affect tissue cooling in healthy lean subjects. All tested cold modalities caused acute increases in cardiovascular strain; however, these increases are no more than what healthy subjects experience with the onset of exercise. PMID:24381698

Holwerda, Seth W.; Trowbridge, Cynthia A.; Womochel, Kathryn S.; Keller, David M.

2013-01-01

259

Effects of betel nut on cardiovascular risk factors in a rat model  

PubMed Central

Background Areca nut (commonly known as betel nut) chewing has been shown to be associated with metabolic syndrome and cardiovascular disease (CVD). The mechanism by which betel nut ingestion could lead to development of CVD is not precisely known; however, dyslipidemia, hyperhomocysteinemia, hypertriglyceridemia and inflammation could be some of the potential risk factors. This study was undertaken to investigate the effects of two dosages of betel nut on homocysteinemia, inflammation and some of the components of metabolic syndrome, such as hypertriglyceridemia, low HDL-cholesterol, obesity and fasting hyperglycemia in a rat model. Methods Thirty-six adult female Sprague Dawley rats, aged 10–12 weeks were divided into three equal groups. Group-1 served as the control group (n = 12) and received water, whereas groups 2 and 3 were given water suspension of betel nut orally in two dosages, 30 mg and 60 mg, respectively for a period of 5 weeks. At the end of the fifth week, the animals were weighed and sacrificed, blood was collected and liver, kidney, spleen and stomach were removed for histological examination. Plasma/serum was analyzed for glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, homocysteine, folate, vitamin B12 and N-acetyl-?-D-glucosaminidase (NAG) – a marker of inflammation. Results When the mean concentration values of 3 groups were compared using one way ANOVA followed by Tukey’s HSD-test, there was a significant increase in the concentration of total cholesterol (p = 0.04) in the group receiving 30 mg/day betel nut compared to the control group. However, administration of a higher dose of betel nut (60 mg/day) had no significant effect on the serum concentrations of glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, and NAG. Histological examination of spleen revealed a dose-dependent extramedullary hematopoiesis. No other remarkable change in the tissues (liver, kidney and stomach) was observed. Mean serum/plasma levels of folate, vitamin B12 and homocysteine were not found to be significantly different in all the groups. Betel nut ingestion had no effect on the mean body weights of rats. Conclusions Low dosage of betel nut is found to be associated with hypercholesterolemia. However, betel nut ingestion is not associated with hyperhomocysteinemia, hypertriglyceridemia, hyperglycemia, inflammation and increase in body weight in a rat model. PMID:23095290

2012-01-01

260

Effects of Mono and Dual Blockade of the Renin-Angiotensin System on Markers of Cardiovascular Status in Hypertensive Patients with Mild and Moderate Renal Failure  

Microsoft Academic Search

Background\\/Aims: Dual renin-angiotensin system (RAS) blockade has no more efficiency to decrease cardiovascular mortality than mono-blockade. Our goal was to explore differences between other cardiovascular markers in patients with RAS blockade. Methods: We analyzed two groups of patients treated with a long-term ACE inhibitor (MONO-group, n = 20) and an ACE inhibitor and angiotensin II receptor blocker (DUAL-group, n =

Gábor Nagy; István A. Szijártó; Balázs Gaszner; Éva Lányi; Lajos Markó; Ákos Mérei; Gergo? A. Molnár; Kinga Németh; József Betlehem; István Wittmann

2011-01-01

261

Emerging anti-cancer therapeutic targets and the cardiovascular system: Is there cause for concern?  

PubMed Central

The race for a cure to cancer continues, fueled by unprecedented discoveries of fundamental biology underlying carcinogenesis and tumorogenesis. The expansion of the target list and tools to approach them is moving the oncology community extraordinarily rapidly to clinical trials, bringing new hope for cancer victims. This effort is also propelling biological discoveries in cardiovascular research as many of the targets being explored in cancer play fundamental roles in the heart and vasculature. The combined efforts of cardiovascular and cancer biologists, along with clinical investigators in these fields, will be needed to understand how to safely exploit these efforts. Here we discuss a few of the many research foci in oncology where we believe such collaboration will be particularly important. PMID:20360265

Peng, Xuyang; Pentassuglia, Laura; Sawyer, Douglas B.

2010-01-01

262

Challenges and opportunities in cardiovascular health informatics.  

PubMed

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

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

2013-03-01

263

Controversies in Cardiovascular Research: Induced pluripotent stem cell-derived cardiomyocytes – boutique science or valuable arrhythmia model?  

PubMed Central

As part of the series on Controversies in Cardiovascular Research, the article reviews the strengths and limitations of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CM) as models of cardiac arrhythmias. Specifically, the article attempts to answer the following questions: Which clinical arrhythmias can be modeled by iPSC-CM? How well can iPSC-CM model adult ventricular myocytes? What are the strengths and limitations of published iPSC-CM arrhythmia models? What new mechanistic insight has been gained? What is the evidence that would support using iPSC-CM to personalize anti-arrhythmic drug therapy? The review also discusses the pros and cons of using the iPSC-CM technology for modeling specific genetic arrhythmia disorders such as long QT syndrome, Brugada Syndrome or Catecholaminergic Polymorphic Ventricular Tachycardia. PMID:23569106

Knollmann, Björn C

2013-01-01

264

Multiple adipose depots increase cardiovascular risk via local and systemic effects  

PubMed Central

Adipose tissue modifies the development of cardiovascular disease in a complex manner: obesity is a major risk factor, but particularly when accompanied with a central fat distribution. For that reason the characteristics of visceral adipose tissue attracted the majority of research interest thus far and measurement of waist circumference is now recommended for everyday clinical practice. However, the direct, causative role of visceral fat in cardiometabolic disease remains to be established. Epidemiological and clinical studies show that accumulation of fat subcutaneously, in the gluteo-femoral area, is protective for cardiovascular disease, but the exact molecular mechanisms remain again unclear. In the last few years, imaging allowed the study of smaller fat depots that may interact locally with important tissues: epicardial fat with the myocardium, perivascular fat with the vessel wall and the developing atherosclerotic plaque, renal sinus fat with the renal artery. Unraveling the heterogeneous fat distribution and metabolic phenotypes in human obesity will facilitate optimal assessment of cardiovascular risk in overweight and obese individuals. PMID:23982264

Karastergiou, Kalypso; Fried, Susan K.

2014-01-01

265

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

PubMed Central

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

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

2012-01-01

266

Inhibiting C-Reactive Protein for the Treatment of Cardiovascular Disease: Promising Evidence from Rodent Models  

PubMed Central

Raised blood C-reactive protein (CRP) level is a predictor of cardiovascular events, but whether blood CRP is causal in the disease process is unknown. The latter would best be defined by pharmacological inhibition of the protein in the context of a randomized case-control study. However, no CRP specific drug is currently available so such a prospective study cannot be performed. Blood CRP is synthesized primarily in the liver and the liver is an organ where antisense oligonucleotide (ASO) drugs accumulate. Taking advantage of this we evaluated the efficacy of CRP specific ASOs in rodents with experimentally induced cardiovascular damage. Treating rats for 4 weeks with a rat CRP-specific ASO achieved >60% reduction of blood CRP. Notably, this effect was associated with improved heart function and pathology following myocardial infarction (induced by ligation of the left anterior descending artery). Likewise in human CRP transgenic mice treated for 2 weeks with a human CRP-specific ASO, blood human CRP was reduced by >70% and carotid artery patency was improved (2 weeks after surgical ligation). CRP specific ASOs might pave the way towards a placebo-controlled trial that could clarify the role of CRP in cardiovascular disease. PMID:24803739

Szalai, Alexander J.; McCrory, Mark A.; Xing, Dongqi; Hage, Fadi G.; Miller, Andrew; Oparil, Suzanne; Chen, Yiu-Fai; Mazzone, Michelle; Early, Richard; Henry, Scott P.; Zanardi, Thomas A.; Graham, Mark J.; Crooke, Rosanne M.

2014-01-01

267

Applications of SPICE for modeling miniaturized biomedical sensor systems  

NASA Technical Reports Server (NTRS)

This paper proposes a model for a miniaturized signal conditioning system for biopotential and ion-selective electrode arrays. The system consists of three main components: sensors, interconnections, and signal conditioning chip. The model for this system is based on SPICE. Transmission-line based equivalent circuits are used to represent the sensors, lumped resistance-capacitance circuits describe the interconnections, and a model for the signal conditioning chip is extracted from its layout. A system for measurements of biopotentials and ionic activities can be miniaturized and optimized for cardiovascular applications based on the development of an integrated SPICE system model of its electrochemical, interconnection, and electronic components.

Mundt, C. W.; Nagle, H. T.

2000-01-01

268

The role of ATP-sensitive potassium channels in cellular function and protection in the cardiovascular system  

PubMed Central

ATP-sensitive potassium channels (KATP) are widely distributed and present in a number of tissues including muscle, pancreatic beta cells and the brain. Their activity is regulated by adenine nucleotides, characteristically being activated by falling ATP and rising ADP levels. Thus, they link cellular metabolism with membrane excitability. Recent studies using genetically modified mice and genomic studies in patients have implicated KATP channels in a number of physiological and pathological processes. In this review, we focus on their role in cellular function and protection particularly in the cardiovascular system. PMID:24102106

Tinker, Andrew; Aziz, Qadeer; Thomas, Alison

2014-01-01

269

Capsaicin-induced metabolic and cardiovascular autonomic improvement in an animal model of the metabolic syndrome.  

PubMed

The metabolic syndrome (MetS) is associated with an increased risk of cardiac mortality, as it is characterised by the clustering of multiple cardiovascular risk factors. Studies have shown that capsaicin (red pepper) may be useful as a nutraceutical, ameliorating metabolic profile and cardiovascular function. The aim of the present study was to investigate the cardiovascular and metabolic effects of orally administered capsaicin in rats with the MetS. Neonate spontaneously hypertensive rats were injected with monosodium glutamate and subjected to one of the following three treatments by oral administration for 14 d, between 27 and 30 weeks: low-dose capsaicin (CAP05, n 18, synthetic capsaicin powder diluted in a vehicle (10 % ethyl alcohol) plus 0·5 mg/kg body weight (BW) of capsaicin); high-dose capsaicin (CAP1, n 19, synthetic capsaicin powder diluted in a vehicle (10 % ethyl alcohol) plus 1 mg/kg BW of capsaicin); control (C, n 18, vehicle). Lee's index, lipid/metabolic profile, and cardiovascular parameters with the rats being conscious, including arterial pressure (AP) and heart rate (HR) variability, as well as aortic wall thickness (haematoxylin and eosin staining) and CD68 (cluster of differentiation 68) antibody levels (monocyte/macrophage immunostaining) were evaluated. Weight, Lee's index, and lipid and metabolic parameters, as well as AP and HR and aortic wall thickness, were similar between the groups. Capsaicin determined HR variability improvement (16·0 (sem 9·0), 31·0 (sem 28·2) and 31·3 (sem 19·0) ms2 for the C, CAP05 and CAP1 groups, respectively, P= 0·003), increased vascular sympathetic drive (low-frequency component of systolic AP variability: 3·3 (sem 2·8), 8·2 (sem 7·7) and 12·1 (sem 8·8) mmHg2 for the C, CAP05 and CAP1 groups, respectively, P< 0·001) and increased ?-index (spontaneous baroreflex sensitivity). The present data show that capsaicin did not improve lipid and glucose abnormalities in rats with the MetS. However, beneficial cardiovascular effects were observed with this nutraceutical. PMID:23968579

Tremarin, Camila da Silva; Casali, Karina Rabello; Meurer, Luise; Schaan, Beatriz D'Agord

2014-01-28

270

Role of the kallikrein–kinin system in the maturation of cardiovascular phenotype  

Microsoft Academic Search

Recent studies indicate that during early phases of life the kallikrein–kinin system (KKS) plays a role in kidney development. In the rat kidney, the spatial and temporal pattern of expression of the genes encoding for kallikrein or bradykinin (BK) B2-receptors parallels postnatal nephrogenesis and blood flow redistribution from the inner to the outer renal cortex. Animal models with genetic dysfunction

Costanza Emanueli; Paolo Madeddu

1999-01-01

271

Validation of a model to investigate the effects of modifying cardiovascular disease (CVD) risk factors on the burden of CVD: the Rotterdam Ischemic Heart Disease and Stroke Computer Simulation (RISC) model  

E-print Network

Abstract Background We developed a Monte Carlo Markov model designed to investigate the effects of modifying cardiovascular disease (CVD) risk factors on the burden of CVD. Internal, predictive, and external validity of the model have not yet been...

van Kempen, Bob JH; Ferket, Bart S; Hofman, Albert; Steyerberg, Ewout W; Colkesen, Ersen B; Boekholdt, S Matthijs; Wareham, Nicholas J; Khaw, Kay-Tee; Hunink, MG M

2012-12-06

272

Mitochondria and Cardiovascular Aging  

PubMed Central

Old age is a major risk factor for cardiovascular diseases. Several lines of evidence in experimental animal models have indicated the central role of mitochondria both in lifespan determination and cardiovascular aging. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and biogenesis as well as the crosstalk between mitochondria and cellular signaling in cardiac and vascular aging. Intrinsic cardiac aging in the murine model closely recapitulates age-related cardiac changes in humans (left ventricular hypertrophy, fibrosis and diastolic dysfunction), while the phenotype of vascular aging include endothelial dysfunction, reduced vascular elasticity and chronic vascular inflammation. Both cardiac and vascular aging involve neurohormonal signaling (e.g. renin-angiotensin, adrenergic, insulin-IGF1 signaling) and cell-autonomous mechanisms. The potential therapeutic strategies to improve mitochondrial function in aging and cardiovascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants, calorie restriction, calorie restriction mimetics and exercise training. PMID:22499901

Dai, Dao-Fu; Ungvari, Zoltan

2013-01-01

273

Mitochondria and cardiovascular aging.  

PubMed

Old age is a major risk factor for cardiovascular diseases. Several lines of evidence in experimental animal models have indicated the central role of mitochondria both in lifespan determination and in cardiovascular aging. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and biogenesis as well as the crosstalk between mitochondria and cellular signaling in cardiac and vascular aging. Intrinsic cardiac aging in the murine model closely recapitulates age-related cardiac changes in humans (left ventricular hypertrophy, fibrosis and diastolic dysfunction), while the phenotype of vascular aging include endothelial dysfunction, reduced vascular elasticity, and chronic vascular inflammation. Both cardiac and vascular aging involve neurohormonal signaling (eg, renin-angiotensin, adrenergic, insulin-IGF1 signaling) and cell-autonomous mechanisms. The potential therapeutic strategies to improve mitochondrial function in aging and cardiovascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants, calorie restriction, calorie restriction mimetics, and exercise training. PMID:22499901

Dai, Dao-Fu; Rabinovitch, Peter S; Ungvari, Zoltan

2012-04-13

274

Macroscopic two-pump two-vasculature cardiovascular model to support treatment of acute heart failure.  

PubMed

Comprehensive understanding of hemodynamics remains a challenge even for expert cardiologists, partially due to a lack of an appropriate macroscopic model. We attempted to amend three major problems of Guyton's conceptual model (unknown left atrial pressure, unilateral heart damage, blood redistribution) and developed a comprehensive macroscopic model of hemodynamics that provides quantitative information. We incorporated a third axis of left atrial pressure, resulting in a 3D coordinate system. Pump functions of left and right heart are expressed by an integrated cardiac output curve, and the capacitive function of total vasculature by a venous return surface. The equations for both the cardiac output curve and venous return surface would facilitate precise diagnosis (especially evaluation of blood volume) and choice of appropriate treatments, including application to autopilot systems. PMID:19965188

Sugimachi, Masaru; Sunagawa, Kenji; Uemura, Kazunori; Kamiya, Atsunori; Shimizu, Shuji; Inagaki, Masashi; Shishido, Toshiaki

2009-01-01

275

HIV and Cardiovascular Disease  

MedlinePLUS

... Select a Language: Fact Sheet 652 HIV and Cardiovascular Disease HIV AND CARDIOVASCULAR DISEASE WHY SHOULD PEOPLE WITH HIV CARE ABOUT CVD? ... OF CVD? WHAT ABOUT CHANGING MEDICATIONS? HIV AND CARDIOVASCULAR DISEASE Cardiovascular disease (CVD) includes a group of problems ...

276

Mouse Models To Study Angiogenesis, Vasculogenesis And Arteriogenesis In The Context Of Cardiovascular Diseases Thierry Couffinhal1,2  

E-print Network

Of Cardiovascular Diseases Thierry Couffinhal1,2 ; Pascale Dufourcq1 , Laurent Barandon1,2 , Lionel Leroux1 in cardiovascular diseases 3. Assessment of angiogenesis, arteriogenesis or vasculogenesis 3.1. Is there an ideal, vasculogenesis and arteriogenesis in the context of cardiovascular diseases. Several quantitative angiogenesis

Paris-Sud XI, Université de

277

Cardiovascular Disease  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cardiovascular disease (CVD), particularly CHD (coronary heart disease) and stroke, remain the leading causes of death of women in America and most developed countries. In recent years the rate of CVD has declined in men but not in women. This is contributed to by an under-recognition of women’s C...

278

[Effects of the 520-day isolation on the functional state of the cardiovascular system].  

PubMed

Purpose of the work was to study the cardiovascular effects of simulated factors in a 520-day crewed mission to Mars, and to validate the diagnostic value of the ultrasonic investigation of microcirculation and endothelium-dependent dilation of the right brachial artery in 6 male volunteers at the age of 28 to 39 years. It appears that 520-d isolation affected intracardiac hemodynamics and endothelium function more dramatically compared with 105-d isolation, increasing the risk of atherosclerosis. These findings add insight into the "cost of human adaptation" to very long isolation. PMID:25365873

Stepanova, G P; Bu?lov, S P; Eshchenko, A I; Skedina, M A; Voronkov, Iu I

2014-01-01

279

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

PubMed

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

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

2014-11-01

280

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

PubMed

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

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

2014-11-27

281

Cardiovascular system in larval zebrafish responds to developmental hypoxia in a family specific manner  

PubMed Central

Background Genetic and environmental variation are both known to influence development. Evolution of a developmental response that is optimized to the environment (adaptive plasticity) requires the existence of genetic variation for that developmental response. In complex traits composed of integrated sets of subsidiary traits, the adaptive process may be slowed by the existence of multiple possible integrated responses. This study tests for family (sibship) specific differences in plastic response to hypoxia in an integrated set of cardiovascular traits in zebrafish. Results Cardiac output, which is the integrated product of several subsidiary traits, varied highly significantly between families, and families differed significantly in the degree and direction of response to developmental oxygen level. The cardiac output response to oxygen environment was entirely family specific with no significant overall trend due to oxygen level. Constituent physiological variables that contribute to cardiac output all showed significant family specific response to hypoxia. Traits that were not directly related to cardiac output, such as arterial and venous diameter, and red blood cell velocities did not respond to hypoxia in a family specific manner. Conclusion Zebrafish families vary in their plastic response to hypoxia. Genetic variation in plastic response to hypoxia may therefore provide the basic ingredient for adaptation to a variable environment. Considerable variation in the degree of familial response to hypoxia exists between different cardiovascular traits that may contribute to cardiac output. It is possible that the integration of several subsidiary traits into cardiac output allows the maintenance of genetic variance in cardiac response. PMID:16539736

Moore, Francisco B-G; Hosey, Michelle; Bagatto, Brian

2006-01-01

282

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

NASA Astrophysics Data System (ADS)

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).

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

2008-03-01

283

Having a Change of Heart: A Lesson on Cardiovascular Anatomy  

NSDL National Science Digital Library

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.

Cynthia Pfirrmann (Scotch Plains-Fanwood High School)

2006-08-01

284

CSU Research Colloquium Cardiovascular Research at CSU  

E-print Network

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

Stephens, Graeme L.

285

Regulation of Cell Physiology and Pathology by Protein S-Glutathionylation: Lessons Learned from the Cardiovascular System  

PubMed Central

Abstract Significance: Reactive oxygen and nitrogen species contributing to homeostatic regulation and the pathogenesis of various cardiovascular diseases, including atherosclerosis, hypertension, endothelial dysfunction, and cardiac hypertrophy, is well established. The ability of oxidant species to mediate such effects is in part dependent on their ability to induce specific modifications on particular amino acids, which alter protein function leading to changes in cell signaling and function. The thiol containing amino acids, methionine and cysteine, are the only oxidized amino acids that undergo reduction by cellular enzymes and are, therefore, prime candidates in regulating physiological signaling. Various reports illustrate the significance of reversible oxidative modifications on cysteine thiols and their importance in modulating cardiovascular function and physiology. Recent Advances: The use of mass spectrometry, novel labeling techniques, and live cell imaging illustrate the emerging importance of reversible thiol modifications in cellular redox signaling and have advanced our analytical abilities. Critical Issues: Distinguishing redox signaling from oxidative stress remains unclear. S-nitrosylation as a precursor of S-glutathionylation is controversial and needs further clarification. Subcellular distribution of glutathione (GSH) may play an important role in local regulation, and targeted tools need to be developed. Furthermore, cellular redundancies of thiol metabolism complicate analysis and interpretation. Future Directions: The development of novel pharmacological analogs that specifically target subcellular compartments of GSH to promote or prevent local protein S-glutathionylation as well as the establishment of conditional gene ablation and transgenic animal models are needed. Antioxid. Redox Signal. 16, 524–542. PMID:22010840

Pimentel, David; Haeussler, Dagmar Johanna; Matsui, Reiko; Burgoyne, Joseph Robert; Cohen, Richard Alan

2012-01-01

286

Sarnoff Cardiovascular Sarnoff Cardiovascular Research Foundation Research Foundation  

E-print Network

Sarnoff Cardiovascular Sarnoff Cardiovascular Research Foundation Research Foundation Medical Student Research Fellowships Inspiring the Physician Sarnoff Cardiovascular Sarnoff Cardiovascular medical Provides medical Sarnoff Cardiovascular Sarnoff Cardiovascular Research Foundation Research

Bushman, Frederic

287

Communication system modeling  

NASA Technical Reports Server (NTRS)

This report presents the results of work on communications systems modeling and covers three different areas of modeling. The first of these deals with the modeling of signals in communication systems in the frequency domain and the calculation of spectra for various modulations. These techniques are applied in determining the frequency spectra produced by a unified carrier system, the down-link portion of the Command and Communications System (CCS). The second modeling area covers the modeling of portions of a communication system on a block basis. A detailed analysis and modeling effort based on control theory is presented along with its application to modeling of the automatic frequency control system of an FM transmitter. A third topic discussed is a method for approximate modeling of stiff systems using state variable techniques.

Holland, L. D.; Walsh, J. R., Jr.; Wetherington, R. D.

1971-01-01

288

Evaluation of the electromechanical properties of the cardiovascular system after prolonged weightlessness  

NASA Technical Reports Server (NTRS)

Devices and techniques for measuring and analyzing systolic time intervals and quantitative phonocardiograms were initiated during Apollo 17. The data show that the systolic time interval from Apollo 17 crewmen remained elevated longer postflight than the response criteria of heart rate, blood pressure, and percent change in leg volume all of which had returned to preflight levels by the second day postflight. Although the systolic time interval values were only slightly outside the preflight fiducial limits, this finding suggested that: the analysis of systolic time intervals may help to identify the mechanisms of postflight orthostatic intolerance by virtue of measuring ventricular function more directly and, the noninvasive technique may prove useful in determining the extent and duration of cardiovascular instability after long duration space flight. The systolic time intervals obtained on the Apollo 17 crewmen during lower body negative pressure were similar to those noted in patients with significant heart disease.

Bergman, S. A., Jr.; Johnson, R. L.; Hoffler, G. W.

1977-01-01

289

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

PubMed Central

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

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

2014-01-01

290

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

PubMed Central

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

Jones, D. R.

1973-01-01

291

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

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

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

292

Cardiovascular Disease-Related Parameters and Oxidative Stress in SHROB Rats, a Model for Metabolic Syndrome  

PubMed Central

SHROB rats have been suggested as a model for metabolic syndrome (MetS) as a situation prior to the onset of CVD or type-2 diabetes, but information on descriptive biochemical parameters for this model is limited. Here, we extensively evaluate parameters related to CVD and oxidative stress (OS) in SHROB rats. SHROB rats were monitored for 15 weeks and compared to a control group of Wistar rats. Body weight was recorded weekly. At the end of the study, parameters related to CVD and OS were evaluated in plasma, urine and different organs. SHROB rats presented statistically significant differences from Wistar rats in CVD risk factors: total cholesterol, LDL-cholesterol, triglycerides, apoA1, apoB100, abdominal fat, insulin, blood pressure, C-reactive protein, ICAM-1 and PAI-1. In adipose tissue, liver and brain, the endogenous antioxidant systems were activated, yet there was no significant oxidative damage to lipids (MDA) or proteins (carbonylation). We conclude that SHROB rats present significant alterations in parameters related to inflammation, endothelial dysfunction, thrombotic activity, insulin resistance and OS measured in plasma as well as enhanced redox defence systems in vital organs that will be useful as markers of MetS and CVD for nutrition interventions. PMID:25115868

Molinar-Toribio, Eunice; Pérez-Jiménez, Jara; Ramos-Romero, Sara; Lluís, Laura; Sánchez-Martos, Vanessa; Taltavull, Núria; Romeu, Marta; Pazos, Manuel; Méndez, Lucía; Miranda, Aníbal; Cascante, Marta; Medina, Isabel; Torres, Josep Lluís

2014-01-01

293

Cardiovascular disease-related parameters and oxidative stress in SHROB rats, a model for metabolic syndrome.  

PubMed

SHROB rats have been suggested as a model for metabolic syndrome (MetS) as a situation prior to the onset of CVD or type-2 diabetes, but information on descriptive biochemical parameters for this model is limited. Here, we extensively evaluate parameters related to CVD and oxidative stress (OS) in SHROB rats. SHROB rats were monitored for 15 weeks and compared to a control group of Wistar rats. Body weight was recorded weekly. At the end of the study, parameters related to CVD and OS were evaluated in plasma, urine and different organs. SHROB rats presented statistically significant differences from Wistar rats in CVD risk factors: total cholesterol, LDL-cholesterol, triglycerides, apoA1, apoB100, abdominal fat, insulin, blood pressure, C-reactive protein, ICAM-1 and PAI-1. In adipose tissue, liver and brain, the endogenous antioxidant systems were activated, yet there was no significant oxidative damage to lipids (MDA) or proteins (carbonylation). We conclude that SHROB rats present significant alterations in parameters related to inflammation, endothelial dysfunction, thrombotic activity, insulin resistance and OS measured in plasma as well as enhanced redox defence systems in vital organs that will be useful as markers of MetS and CVD for nutrition interventions. PMID:25115868

Molinar-Toribio, Eunice; Pérez-Jiménez, Jara; Ramos-Romero, Sara; Lluís, Laura; Sánchez-Martos, Vanessa; Taltavull, Núria; Romeu, Marta; Pazos, Manuel; Méndez, Lucía; Miranda, Aníbal; Cascante, Marta; Medina, Isabel; Torres, Josep Lluís

2014-01-01

294

Multiscale modelling of the circulatory system: a preliminary analysis  

Microsoft Academic Search

.   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

Luca Formaggia; Fabio Nobile; Alfio Quarteroni; Alessandro Veneziani

1999-01-01

295

NEP systems model  

NASA Astrophysics Data System (ADS)

Various aspects of nuclear electric propulsion (NEP) systems analysis and modeling are discussed. The following specific topics are covered: (1) systems analysis challenges; (2) goals for NEP systems analysis; (3) the Nuclear Propulsion Office approach; and (4) NEP subsystem model development. The discussion is presented in vugraph form.

Gilland, Jim; George, Jeffrey A.

296

[Role of endocannabinoid 2-arachidonoylglycerol in the physiology and pathophysiology of the cardiovascular system].  

PubMed

Cannabinoids, the active ingredients of Cannabis sativa var. indica, have been used by humans as recreational and therapeutic agents for thousands of years. This group of substances also includes synthetic ligands and, synthesized in the body of humans and animals, endocannabinoids. The best known compound classified as an endogenous cannabinoid is anandamide. However, recent studies show that another compound of this group, 2-arachidonoylglycerol (2-AG), also performs many important functions in the organism. 2-Arachidonoylglycerol plays an important role in the regulation of the circulatory system via direct and/or indirect, through their metabolites, effects on blood vessels and/or heart. Accumulating evidence reveals that 2-AG is involved in the pathogenesis of various shocks and atherosclerosis. Thus, it may be a novel attractive therapeutic target. However, because of rapid metabolism and opposite effects dependent on the experimental model, the function of 2-AG still remains to be established. PMID:24934539

Karabowicz, Piotr; Grz?da, Emilia; Baranowska-Kuczko, Marta; Malinowska, Barbara

2014-01-01

297

Glyphosate-Based Herbicides Potently Affect Cardiovascular System in Mammals: Review of the Literature.  

PubMed

In glyphosate (G)-based herbicides (GBHs), the declared active principle G is mixed with several adjuvants that help it to penetrate the plants' cell membranes and its stabilization and liposolubility. Its utilization is growing with genetically modified organisms engineered to tolerate GBH. Millions of farmers suffer poisoning and death in developing countries, and occupational exposures and suicide make GBH toxicity a worldwide concern. As GBH is found in human plasma, widespread hospital facilities for measuring it should be encouraged. Plasma determination is an essential prerequisite for risk assessment in GBH intoxication. Only when standard ECGs were performed, at least one abnormal ECG was detected in the large majority of cases after intoxication. QTc prolongation and arrhythmias along with first-degree atrioventricular block were observed after GBH intoxication. Thus, life-threatening arrhythmias might be the cause of death in GBH intoxication. Cardiac cellular effects of GBH were reviewed along with few case reports in men and scanty larger studies. We observed in two mammalian species (rats and rabbits) direct cardiac electrophysiological changes, conduction blocks and arrhythmias among GBH-mediated effects. Plasmatic (and urine) level determinations of G and electrocardiographic Holter monitoring seem warranted to ascertain whether cardiovascular risk among agro-alimentary workers might be defined. PMID:25245870

Gress, Steeve; Lemoine, Sandrine; Séralini, Gilles-Eric; Puddu, Paolo Emilio

2014-09-23

298

The Role of Notch in the Cardiovascular System: Potential Adverse Effects of Investigational Notch Inhibitors  

PubMed Central

Targeting the Notch pathway is a new promising therapeutic approach for cancer patients. Inhibition of Notch is effective in the oncology setting because it causes a reduction of highly proliferative tumor cells and it inhibits survival of cancer stem cells, which are considered responsible for tumor recurrence and metastasis. Additionally, since Delta-like ligand 4 (Dll4)-activated Notch signaling is a major modulator of angiogenesis, anti-Dll4 agents are being investigated to reduce vascularization of the tumor. Notch plays a major role in the heart during the development and, after birth, in response to cardiac damage. Therefore, agents used to inhibit Notch in the tumors (gamma secretase inhibitors and anti-Dll4 agents) could potentially affect myocardial repair. The past experience with trastuzumab and other tyrosine kinase inhibitors used for cancer therapy demonstrates that the possible cardiotoxicity of agents targeting shared pathways between cancer and heart and the vasculature should be considered. To date, Notch inhibition in cancer patients has resulted only in mild gastrointestinal toxicity. Little is known about the potential long-term cardiotoxicity associated to Notch inhibition in cancer patients. In this review, we will focus on mechanisms through which inhibition of Notch signaling could lead to cardiomyocytes and endothelial dysfunctions. These adverse effects could contrast with the benefits of therapeutic responses in cancer cells during times of increased cardiac stress and/or in the presence of cardiovascular risk factor. PMID:25629006

Rizzo, Paola; Mele, Donato; Caliceti, Cristiana; Pannella, Micaela; Fortini, Cinzia; Clementz, Anthony George; Morelli, Marco Bruno; Aquila, Giorgio; Ameri, Pietro; Ferrari, Roberto

2015-01-01

299

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

NASA Astrophysics Data System (ADS)

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.

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

2006-03-01

300

Comparison of equilibrium radionuclide ventriculography with cardiovascular magnetic resonance for assessing the systemic right ventricle after Mustard or Senning procedures for complete transposition of the great arteries  

Microsoft Academic Search

We assessed the utility of equilibrium radionuclide ventriculography for assessing function of the systemic right ventricle by comparing it with cardiovascular magnetic resonance (CMR) in subjects who had undergone the Mustard or Senning operations for complete transposition of the great arteries. The 95% limits of agreement for right ventricular ejection fraction by the 2 techniques were 15.8% to ?16.0%, demonstrating

Tim S. Hornung; Constantinos Anagnostopoulos; Pushan Bhardwaj; Philip J. Kilner; Periklis A. Davlouros; James Bailey; Jane M. Francis; Dudley J. Pennell; S. Richard Underwood; Michael A. Gatzoulis

2003-01-01

301

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...

302

Chronic hypoxic incubation blunts thermally dependent cholinergic tone on the cardiovascular system in embryonic American alligator (Alligator mississippiensis).  

PubMed

Environmental conditions play a major role in shaping reptilian embryonic development, but studies addressing the impact of interactions between chronic and acute environmental stressors on embryonic systems are lacking. In the present study, we investigated thermal dependence of cholinergic and adrenergic cardiovascular tone in embryonic American alligators (Alligator mississippiensis) and assessed possible phenotypic plasticity in a chronic hypoxic incubation treatment. We compared changes in heart rate (f H) and mean arterial blood pressure (P M) for chronically hypoxic and normoxic-incubated embryos after cholinergic and adrenergic blockade following three different acute temperature treatments: (1) 30 °C (control incubation temperature), (2) acute, progressive decrease 30-24 °C then held at 24 °C, and (3) acute, progressive increase 30-36 °C then held at 36 °C. f H progressively fell in response to decreasing temperature and rose in response to increasing temperature. P M did not significantly change with decreasing temperature, but was lowered significantly with increasing acute temperature in the normoxic group at 90 % of development only. Propranolol administration (? adrenergic antagonist) produced a significant f H decrease at 24, 30, and 36 °C that was similar at all temperatures for all groups. For normoxic-incubated embryos at 90 % of development, atropine administration (cholinergic antagonist) significantly increased f H in both 24 and 36 °C treatments, but not in the 30 °C control treatment. This atropine response at 24 and 36 °C demonstrated acute thermally dependent cholinergic tone on f H late in development for normoxic-incubated, but not chronically hypoxic-incubated embryos. Collectively, data indicated that cardiovascular control mechanisms in embryonic alligators may be activated by thermal extremes, and the maturation of control mechanisms was delayed by chronic hypoxia. PMID:23632626

Marks, Chris; Eme, John; Elsey, Ruth M; Crossley, Dane A

2013-10-01

303

A century old renin-angiotensin system still grows with endless possibilities: AT1 receptor signaling cascades in cardiovascular physiopathology.  

PubMed

Ang II, the primary effector pleiotropic hormone of the renin-angiotensin system (RAS) cascade, mediates physiological control of blood pressure and electrolyte balance through its action on vascular tone, aldosterone secretion, renal sodium absorption, water intake, sympathetic activity and vasopressin release. It affects the function of most of the organs far beyond blood pressure control including heart, blood vessels, kidney and brain, thus, causing both beneficial and deleterious effects. However, the protective axis of the RAS composed of ACE2, Ang (1-7), alamandine, and Mas and MargD receptors might oppose some harmful effects of Ang II and might promote beneficial cardiovascular effects. Newly identified RAS family peptides, Ang A and angioprotectin, further extend the complexities in understanding the cardiovascular physiopathology of RAS. Most of the diverse actions of Ang II are mediated by AT1 receptors, which couple to classical Gq/11 protein and activate multiple downstream signals, including PKC, ERK1/2, Raf, tyrosine kinases, receptor tyrosine kinases (EGFR, PDGF, insulin receptor), nuclear factor ?B and reactive oxygen species (ROS). Receptor activation via G12/13 stimulates Rho-kinase, which causes vascular contraction and hypertrophy. The AT1 receptor activation also stimulates G protein-independent signaling pathways such as ?-arrestin-mediated MAPK activation and Src-JAK/STAT. AT1 receptor-mediated activation of NADPH oxidase releases ROS, resulting in the activation of pro-inflammatory transcription factors and stimulation of small G proteins such as Ras, Rac and RhoA. The components of the RAS and the major Ang II-induced signaling cascades of AT1 receptors are reviewed. PMID:25007996

Balakumar, Pitchai; Jagadeesh, Gowraganahalli

2014-10-01

304

A Model of Cardiovascular Disease Giving a Plausible Mechanism for the Effect of Fractionated Low-Dose Ionizing Radiation Exposure  

Microsoft Academic Search

Atherosclerosis is the main cause of coronary heart disease and stroke, the two major causes of death in developed society. There is emerging evidence of excess risk of cardiovascular disease at low radiation doses in various occupationally exposed groups receiving small daily radiation doses. Assuming that they are causal, the mechanisms for effects of chronic fractionated radiation exposures on cardiovascular

Mark P. Little; Anna Gola; Ioanna Tzoulaki

2009-01-01

305

CARDIOVASCULAR Editor, Nature  

E-print Network

CARDIOVASCULAR DISEASE Editor, Nature Philip Campbell Insights Publisher Sarah Greaves Publishing Imaging of atherosclerotic cardiovascular disease J. Sanz & Z. A. Fayad Cover illustration The human heart is increasing in the developing world. Cardiovascular disease usually stems from vascular dysfunction

Cai, Long

306

[Effects of isosorbide 5-mononitrate on cardiovascular function. (I). Effects on the left ventricular system].  

PubMed

Effects of isosorbide 5-mononitrate (5-ISMN) on cardiovascular function were compared with those of isosorbide dinitrate (ISDN), verapamil and propranolol. In anesthetized open-chest dogs, intravenous injection of 5-ISMN (1 mg/kg, 3 mg/kg) scarcely decreased cardiac contractile force (CCF) and heart rate (HR). The systolic blood pressure (SBP) fell in a dose-dependent manner, and the degree of the change was greater than that in diastolic blood pressure (DBP). Especially, left ventricular pressure (LVP) and left ventricular dp/dt (LVdp/dt) were significantly decreased, and a considerable reduction in left ventricular end-diastolic pressure (LVEDP) was also observed. Intravenous injection of verapamil (0.3 mg/kg) considerably lowered DBP. While HR, CCF, LVP and LVdp/dt were markedly decreased, LVEDP showed a moderate increase. Propranolol (0.5 mg/kg, i.v.) greatly decreased LVdp/dt together with HR and CCF. Conversely, LVEDP showed a slight increase. There was no change in SBP, DBP and LVP. The vasodilating potency of 5-ISMN was 150 times smaller than that of ISDN on the contractile response in isolated rabbit thoracic aorta. On the other hand, in terms of decrease in pulse pressure, the potency exhibited by 5-ISMN was about 4 times (intravenous administration in anesthetized dogs) or 1.5 times (oral administration in conscious dogs) smaller than that of ISDN. The present results suggest that 5-ISMN shows a high bioavailability and a potency comparable to ISDN, especially in the case of peroral administration. Taking these results together with the fact that transient left ventricular failure occurs during myocardial ischemia into consideration, it is thought that peroral 5-ISMN preparation may be useful in the therapy of angina pectoris. PMID:4029805

Kogi, K; Saito, T

1985-05-01

307

38 CFR 4.104 - Schedule of ratings-cardiovascular system.  

Code of Federal Regulations, 2012 CFR

...symptomatic, evaluate according to body system affected. Following surgery, evaluate residuals under the body system affected. 7113Arteriovenous fistula...71 FR52460, Sept. 6, 2006] The Digestive...

2012-07-01

308

38 CFR 4.104 - Schedule of ratings-cardiovascular system.  

Code of Federal Regulations, 2013 CFR

...symptomatic, evaluate according to body system affected. Following surgery, evaluate residuals under the body system affected. 7113Arteriovenous fistula...71 FR52460, Sept. 6, 2006] The Digestive...

2013-07-01

309

38 CFR 4.104 - Schedule of ratings-cardiovascular system.  

Code of Federal Regulations, 2014 CFR

...symptomatic, evaluate according to body system affected. Following surgery, evaluate residuals under the body system affected. 7113Arteriovenous fistula...79 FR 2100, Jan. 13, 2014] The Digestive...

2014-07-01

310

38 CFR 4.104 - Schedule of ratings-cardiovascular system.  

Code of Federal Regulations, 2011 CFR

...symptomatic, evaluate according to body system affected. Following surgery, evaluate residuals under the body system affected. 7113Arteriovenous fistula...71 FR52460, Sept. 6, 2006] The Digestive...

2011-07-01

311

38 CFR 4.104 - Schedule of ratings-cardiovascular system.  

Code of Federal Regulations, 2010 CFR

...symptomatic, evaluate according to body system affected. Following surgery, evaluate residuals under the body system affected. 7113Arteriovenous fistula...71 FR52460, Sept. 6, 2006] The Digestive...

2010-07-01

312

MLS: Airplane system modeling  

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

313

Therapeutic manipulation of glucocorticoid metabolism in cardiovascular disease  

PubMed Central

The therapeutic potential for manipulation of glucocorticoid metabolism in cardiovascular disease was revolutionized by the recognition that access of glucocorticoids to their receptors is regulated in a tissue-specific manner by the isozymes of 11?-hydroxysteroid dehydrogenase. Selective inhibitors of 11?-hydroxysteroid dehydrogenase type 1 have been shown recently to ameliorate cardiovascular risk factors and inhibit the development of atherosclerosis. This article addresses the possibility that inhibition of 11?-hydroxsteroid dehydrogenase type 1 activity in cells of the cardiovascular system contributes to this beneficial action. The link between glucocorticoids and cardiovascular disease is complex as glucocorticoid excess is linked with increased cardiovascular events but glucocorticoid administration can reduce atherogenesis and restenosis in animal models. There is considerable evidence that glucocorticoids can interact directly with cells of the cardiovascular system to alter their function and structure and the inflammatory response to injury. These actions may be regulated by glucocorticoid and/or mineralocorticoid receptors but are also dependent on the 11?-hydroxysteroid dehydrogenases which may be expressed in cardiac, vascular (endothelial, smooth muscle) and inflammatory (macrophages, neutrophils) cells. The activity of 11?-hydroxysteroid dehydrogenases in these cells is dependent upon differentiation state, the action of pro-inflammaotory cytokines and the influence of endogenous inhibitors (oxysterols, bile acids). Further investigations are required to clarify the link between glucocorticoid excess and cardiovascular events and to determine the mechanism through which glucocorticoid treatment inhibits atherosclerosis/restenosis. This will provide greater insights into the potential benefit of selective 11?-hydroxysteroid dehydrogenase inhibitors in treatment of cardiovascular disease. PMID:19239478

Hadoke, Patrick WF; Iqbal, Javaid; Walker, Brian R

2009-01-01

314

Marathon run: cardiovascular adaptation and cardiovascular risk.  

PubMed

The first marathon run as an athletic event took place in the context of the Olympic Games in 1896 in Athens, Greece. Today, participation in a 'marathon run' has become a global phenomenon attracting young professional athletes as well as millions of mainly middle-aged amateur athletes worldwide each year. One of the main motives for these amateur marathon runners is the expectation that endurance exercise (EE) delivers profound beneficial health effects. However, with respect to the cardiovascular system, a controversial debate has emerged whether the marathon run itself is healthy or potentially harmful to the cardiovascular system, especially in middle-aged non-elite male amateur runners. In this cohort, exercise-induced increases in cardiac biomarkers-troponin and brain natriuretic peptide-and acute functional cardiac alterations have been observed and interpreted as potential cardiac damage. Furthermore, in the cohort of 40- to 65-year-old males engaged in intensive EE, a significant risk for the development of atrial fibrillation has been identified. Fortunately, recent studies demonstrated a normalization of the cardiac biomarkers and the functional alterations within a short time frame. Therefore, these alterations may be perceived as physiological myocardial reactions to the strenuous exercise and the term 'cardiac fatigue' has been coined. This interpretation is supported by a recent analysis of 10.9 million marathon runners demonstrating that there was no significantly increased overall risk of cardiac arrest during long-distance running races. In conclusion, intensive and long-lasting EE, e.g. running a full-distance Marathon, results in high cardiovascular strain whose clinical relevance especially for middle-aged and older athletes is unclear and remains a matter of controversy. Furthermore, there is a need for evidence-based recommendations with respect to medical screening and training strategies especially in male amateur runners over the age of 35 years engaged in regular and intensive EE. PMID:24408890

Predel, Hans-Georg

2014-11-21

315

General pharmacology of CKD-732, a new anticancer agent: effects on central nervous, cardiovascular, and respiratory system.  

PubMed

CKD-732 [6-O-(4-dimethylaminoethoxy) cinnamoyl fumagillol hemioxalate] is a new fumagillin anticancer drug that belongs to an angiogenesis inhibitor. Its effect on the central nervous system (CNS), general behavior, cardiovascular-respiratory system and the other organ systems were studied. CKD-732 was intravenously administered with the dosages of 10, 30, 40 or 50 mg/kg and the highest dosage of 50 mg/kg prolonged the hexobarbital-induced sleep time. CKD-732 at the dosage of 50 mg/kg, also, caused the decrease of body temperature from 15 to 120 min after the administration, which was recovered at 240 min. In the study of the effects on gastric secretion, CKD-732 induced the increase of pH and decrease of total acidity. However, CKD-732 showed no effect on general behavior, spontaneous locomotor activity, motor coordination, analgesia, convulsion, mean arterial pressure, and cardiac functions except for heart rate of isolated rat heart, respiration, isolated smooth muscle, intestinal charcoal transport and renal function. Based on the results, we suggested that CKD-732 is safe general pharmacologically at clinical supposed dose (1.75 mg/kg) and demonstrated to have much better safety than other fumagillin derivatives. PMID:15684472

Kim, Eun-Joo; Shin, Won-Ho

2005-02-01

316

Ventricular repolarization during cardiovascular autonomic function testing.  

E-print Network

??The autonomic nervous system is an important modulator of ventricular repolarization and arrhythmia vulnerability. This study explored the effects of cardiovascular autonomic function tests on… (more)

Haapalahti, Petri

2008-01-01

317

Coffee: A Selected Overview of Beneficial or Harmful Effects on the Cardiovascular System?  

PubMed

With a history that began in 800 A.D., coffee is the most popular drink known and as a result, the issues regarding its physiologic effects deserve attention. Maintaining alertness is a well-known benefit and in addition, the cardiovascular (CV) effects of the active compounds, which include polyphenols and caffeine, must be considered. Genetics are relevant and where slow caffeine metabolism is inherent, the risk of nonfatal myocardial (MI) has been shown to be increased. Overall risk for coronary heart disease (CHD) is not supported and unless there is excessive intake, congestive heart failure (CHF) is not adversely affected; in moderation, there may be some benefit for CHF. There is no apparent increased risk of sudden cardiac death (SCD). Overall, there also appears to be a beneficial inverse association with all-cause mortality, although this is not absolute for extra heavy intake. Benefit in reducing stroke also has supportive evidence. Hypertension is not increased by coffee. Boiled and unfiltered coffee appears to increase plasma cholesterol and triglycerides but for the overall metabolic syndrome, there appears to be benefit. There is also some evidence that paper-filtered coffee results in an increase in some markers of inflammation. Association of coffee with arrhythmias has been a major concern though in moderation it is not a significant overall problem. Therefore, only if a patient were to associate major arrhythmic symptoms with coffee would cessation have to be advised. Where coffee clearly shines from a CV standpoint is in the established decrease in onset of type 2 diabetes mellitus (DM). Any benefit or harm has always been attributed to caffeine as the apparent major component. However, coffee contains a myriad of compounds, including polyphenols. These other substances may be most relevant for potential benefit or harm and some of these may be partially removed or altered by coffee preparation methods such as paper filtration. Multiple studies support this by what appears to be no CV advantage or disadvantage for decaffeinated coffee. The bottom line on coffee, for those who enjoy the brew, is that it is a wonderful beverage with rare associated CV disadvantage and with much to recommend it from an overall CV standpoint. PMID:25277696

Whayne Jr, Thomas F

2014-10-01

318

Interventional cardiovascular magnetic resonance imaging  

PubMed Central

Magnetic resonance imaging (MRI) provides structural and functional cardiovascular information with excellent soft tissue contrast. Real-time MRI can guide transcatheter cardiovascular interventions in large animal models, and may prove superior to x-ray and adjunct modalities for peripheral vascular, structural heart and cardiac electrophysiology applications. We describe technical considerations, pre-clinical work and early clinical studies in this emerging field. PMID:17662914

Raman, Venkatesh K.; Lederman, Robert J.

2008-01-01

319

Reinforced pericardium as a hybrid material for cardiovascular applications.  

PubMed

Pericardium-based cardiovascular devices are currently bound by a 10-year maximum lifetime due to detrimental calcification and degradation. The goal of this work is to develop a novel synthetic material to create a lasting replacement for malfunctioning or diseased tissue in the cardiovascular system. This study couples poly(propylene fumarate) (PPF) and a natural biomaterial together in an unprecedented hybrid composite and evaluates the composite versus the standard glutaraldehyde-treated tissue. The polymer reinforcement is hypothesized to provide initial physical protection from proteolytic enzymes and degradation, but leave the original collagen and elastin matrix unaltered. The calcification rate and durability of the hybrid material are evaluated in vitro and in an in vivo subdermal animal model. Results demonstrate that PPF is an effective support and leads to significantly less calcium deposition, important metrics when evaluating cardiovascular material. By avoiding chemical crosslinking of the tissue and associated side effects, PPF-reinforced pericardium as a biohybrid material offers a promising potential direction for further development in cardiovascular material alternatives. Eliminating the basis for the majority of cardiovascular prosthetic failures could revolutionize expectations for extent of cardiovascular repair. PMID:25236439

Bracaglia, Laura G; Yu, Li; Hibino, Narutoshi; Fisher, John P

2014-11-01

320

Developmental Programming of Cardiovascular Disease Following Intrauterine Growth Restriction: Findings Utilising A Rat Model of Maternal Protein Restriction  

PubMed Central

Over recent years, studies have demonstrated links between risk of cardiovascular disease in adulthood and adverse events that occurred very early in life during fetal development. The concept that there are embryonic and fetal adaptive responses to a sub-optimal intrauterine environment often brought about by poor maternal diet that result in permanent adverse consequences to life-long health is consistent with the definition of “programming”. The purpose of this review is to provide an overview of the current knowledge of the effects of intrauterine growth restriction (IUGR) on long-term cardiac structure and function, with particular emphasis on the effects of maternal protein restriction. Much of our recent knowledge has been derived from animal models. We review the current literature of one of the most commonly used models of IUGR (maternal protein restriction in rats), in relation to birth weight and postnatal growth, blood pressure and cardiac structure and function. In doing so, we highlight the complexity of developmental programming, with regards to timing, degree of severity of the insult, genotype and the subsequent postnatal phenotype. PMID:25551250

Zohdi, Vladislava; Lim, Kyungjoon; Pearson, James T.; Black, M. Jane

2014-01-01

321

Efficient computation of interacting model systems.  

PubMed

Physiological processes in the human body can be predicted by mathematical models. Medical Decision Support Systems (MDSS) might exploit these predictions when optimizing therapy settings. In critically ill patients depending on mechanical ventilation, these predictions should also consider other organ systems of the human body. In a previously presented framework we combine elements of three model families: respiratory mechanics, cardiovascular dynamics and gas exchange. Computing combinations of moderately complex submodels showed to be computationally costly thus limiting the applicability of those model combinations in an MDSS. A decoupled computing approach was therefore developed, which enables individual evaluation of every submodel. Direct model interaction is not possible in separate calculations. Therefore, interface signals need to be substituted by estimates. These estimates are iteratively improved by increasing model detail in every iteration exploiting the hierarchical structure of the implemented model families. Simulation error converged to a minimum after three iterations. Maximum simulation error showed to be 1.44% compared to the original common coupled computing approach. Simulation error was found to be below measurement noise generally found in clinical data. Simulation time was reduced by factor 34 using one iteration and factor 13 using three iterations. Following the proposed calculation scheme moderately complex model combinations seem to be applicable for model based decision support. PMID:23395682

Kretschmer, J; Schranz, C; Knöbel, C; Wingender, J; Koch, E; Möller, K

2013-06-01

322

Model-Based Systems  

NASA Technical Reports Server (NTRS)

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.

Frisch, Harold P.

2007-01-01

323

Simulation of cardiovascular diseases using electronic circuits  

Microsoft Academic Search

We have developed an electronic circuit to simulate the behavior of the cardiovascular system under normal or pathological conditions. The current, voltage, charge, resistance and capacitance of the circuit correspond to flow, blood pressure, volume, resistance and capacitance of the simulated cardiovascular system, respectively. We have implemented a circuit with two ventricles separated from the systemic and the pulmonary circulation

D. G. Tsalikakis; D. I. Fotiadis; D. Sideris

2003-01-01

324

Quantitative Efficacy of Diagnosis Procedure Combination Payment System in Division of Cardiovascular Surgery  

Microsoft Academic Search

Japanese health care system has been characterized by universal health-insurance coverage, free access to doctors and hospitals, fee-for-service payment system (FFS) by treatment related groups, and prospective payment system (PPS). Recently, the annual medical expenditure has been increasing year by year. It is thought that FFS is a major cause for the expansion of medical costs because of weak incentives

Yuko Fujimura; Hideji Tanii; Kiyofumi Saijoh

2010-01-01

325

Simulating physiological interactions in a hybrid system of mathematical models.  

PubMed

Mathematical models can be deployed to simulate physiological processes of the human organism. Exploiting these simulations, reactions of a patient to changes in the therapy regime can be predicted. Based on these predictions, medical decision support systems (MDSS) can help in optimizing medical therapy. An MDSS designed to support mechanical ventilation in critically ill patients should not only consider respiratory mechanics but should also consider other systems of the human organism such as gas exchange or blood circulation. A specially designed framework allows combining three model families (respiratory mechanics, cardiovascular dynamics and gas exchange) to predict the outcome of a therapy setting. Elements of the three model families are dynamically combined to form a complex model system with interacting submodels. Tests revealed that complex model combinations are not computationally feasible. In most patients, cardiovascular physiology could be simulated by simplified models decreasing computational costs. Thus, a simplified cardiovascular model that is able to reproduce basic physiological behavior is introduced. This model purely consists of difference equations and does not require special algorithms to be solved numerically. The model is based on a beat-to-beat model which has been extended to react to intrathoracic pressure levels that are present during mechanical ventilation. The introduced reaction to intrathoracic pressure levels as found during mechanical ventilation has been tuned to mimic the behavior of a complex 19-compartment model. Tests revealed that the model is able to represent general system behavior comparable to the 19-compartment model closely. Blood pressures were calculated with a maximum deviation of 1.8 % in systolic pressure and 3.5 % in diastolic pressure, leading to a simulation error of 0.3 % in cardiac output. The gas exchange submodel being reactive to changes in cardiac output showed a resulting deviation of less than 0.1 %. Therefore, the proposed model is usable in combinations where cardiovascular simulation does not have to be detailed. Computing costs have been decreased dramatically by a factor 186 compared to a model combination employing the 19-compartment model. PMID:23990270

Kretschmer, Jörn; Haunsberger, Thomas; Drost, Erick; Koch, Edmund; Möller, Knut

2014-12-01

326

Pulmonary Toxicity and Modifications in Iron Homeostasis Following Libby Amphibole Asbestos Exposure in Rat Models of Cardiovascular Disease  

EPA Science Inventory

Rationale: Individuals suffering from cardiovascular disease (CVD) develop iron dysregulation which may influence pulmonary toxicity and injury upon exposure to asbestos. We hypothesized spontaneously hypertensive (SH) and spontaneously hypertensive heart failure (SHHF) rats woul...

327

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 ...

328

Systemic and Vascular Alterations in Healthy and Cardiovascular Compromised Rats Exposed to Libby Amphibole  

EPA Science Inventory

Rationale: Acute pulmonary injury and chronic disease can impact systemic vasculature because the lung capillary network can release inflammogenic and vasoactive mediators into the circulation. Occupational exposure to Libby amphibole (LA) type asbestos is associated with increas...

329

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

NASA Technical Reports Server (NTRS)

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.

Haber, E.

1975-01-01

330

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

PubMed Central

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

2013-01-01

331

Cardiovascular disease in latin american patients with systemic lupus erythematosus: a cross-sectional study and a systematic review.  

PubMed

Objective. This study was performed to determine the prevalence of and associated risk factors for cardiovascular disease (CVD) in Latin American (LA) patients with systemic lupus erythematosus (SLE). Methods. First, a cross-sectional analytical study was conducted in 310 Colombian patients with SLE in whom CVD was assessed. Associated factors were examined by multivariate regression analyses. Second, a systematic review of the literature on CVD in SLE in LA was performed. Results. There were 133 (36.5%) Colombian SLE patients with CVD. Dyslipidemia, smoking, coffee consumption, and pleural effusion were positively associated with CVD. An independent effect of coffee consumption and cigarette on CVD was found regardless of gender and duration of disease. In the systematic review, 60 articles fulfilling the eligibility criteria were included. A wide range of CVD prevalence was found (4%-79.5%). Several studies reported ancestry, genetic factors, and polyautoimmunity as novel risk factors for such a condition. Conclusions. A high rate of CVD is observed in LA patients with SLE. Awareness of the observed risk factors should encourage preventive population strategies for CVD in patients with SLE aimed at facilitating the suppression of cigarette smoking and coffee consumption as well as at the tight control of dyslipidemia and other modifiable risk factors. PMID:24294522

Amaya-Amaya, Jenny; Sarmiento-Monroy, Juan Camilo; Caro-Moreno, Julián; Molano-González, Nicolás; Mantilla, Rubén D; Rojas-Villarraga, Adriana; Anaya, Juan-Manuel

2013-01-01

332

Cardiovascular Disease in Latin American Patients with Systemic Lupus Erythematosus: A Cross-Sectional Study and a Systematic Review  

PubMed Central

Objective. This study was performed to determine the prevalence of and associated risk factors for cardiovascular disease (CVD) in Latin American (LA) patients with systemic lupus erythematosus (SLE). Methods. First, a cross-sectional analytical study was conducted in 310 Colombian patients with SLE in whom CVD was assessed. Associated factors were examined by multivariate regression analyses. Second, a systematic review of the literature on CVD in SLE in LA was performed. Results. There were 133 (36.5%) Colombian SLE patients with CVD. Dyslipidemia, smoking, coffee consumption, and pleural effusion were positively associated with CVD. An independent effect of coffee consumption and cigarette on CVD was found regardless of gender and duration of disease. In the systematic review, 60 articles fulfilling the eligibility criteria were included. A wide range of CVD prevalence was found (4%–79.5%). Several studies reported ancestry, genetic factors, and polyautoimmunity as novel risk factors for such a condition. Conclusions. A high rate of CVD is observed in LA patients with SLE. Awareness of the observed risk factors should encourage preventive population strategies for CVD in patients with SLE aimed at facilitating the suppression of cigarette smoking and coffee consumption as well as at the tight control of dyslipidemia and other modifiable risk factors. PMID:24294522

Amaya-Amaya, Jenny; Caro-Moreno, Julián; Molano-González, Nicolás; Mantilla, Rubén D.; Rojas-Villarraga, Adriana; Anaya, Juan-Manuel

2013-01-01

333

Multiscale Cloud System Modeling  

NASA Technical Reports Server (NTRS)

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.

Tao, Wei-Kuo; Moncrieff, Mitchell W.

2009-01-01

334

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

PubMed

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

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

2014-10-01

335

Effects of intra-aortic balloon pump timing on baroreflex activities in a closed-loop cardiovascular hybrid model.  

PubMed

Despite 50 years of research to assess the intra-aortic balloon pump (IABP) effects on patients' hemodynamics, some issues related to the effects of this therapy are still not fully understood. One of these issues is the effect of IABP, its inflation timing and duration on peripheral circulation autonomic controls. This work provides a systematic analysis of IABP effects on baroreflex using a cardiovascular hybrid model, which consists of computational and hydraulic submodels. The work also included a baroreflex computational model that was connected to a hydraulic model with a 40-cm(3) balloon. The IABP was operated at different inflation trigger timings (-0.14 to 0.31?s) and inflation durations (0.05-0.45?s), with time of the dicrotic notch being taken as t?=?0. Baroreflex-dependent parameters-afferent and efferent pathway activity, heart rate, peripheral resistance, and venous tone-were evaluated at each of the inflation trigger times and durations considered. Balloon early inflation (0.09?s before the dicrotic notch) with inflation duration of 0.25?s generated a maximum net increment of afferent pathway activity of 10%, thus leading to a decrement of efferent sympathetic activity by 15.3% compared with baseline values. These times also resulted in a reduction in peripheral resistance and heart rate by 4 and 4.3% compared with baseline value. We conclude that optimum IABP triggering time results in positive effects on peripheral circulation autonomic controls. Conversely, if the balloon is not properly timed, peripheral resistance and heart rate may even increase, which could lead to detrimental outcomes. PMID:23121229

Fresiello, Libera; Khir, Ashraf William; Di Molfetta, Arianna; Kozarski, Maciej; Ferrari, Gianfranco

2013-03-01

336

Cardiovascular physiology at high altitude.  

PubMed

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

Hooper, T; Mellor, A

2011-03-01

337

Effects of a computerized decision support system in improving pharmacological management in high-risk cardiovascular patients: A cluster-randomized open-label controlled trial.  

PubMed

This study was aimed to investigate the effects of computerized decision support system in improving the prescription of drugs for cardiovascular prevention. A total of 197 Italian general practitioners were randomly allocated to receive either the alerting computerized decision support system integrated into standard software (intervention arm) or the standard software alone (control arm). Data on 21230 patients with diabetes, 3956 with acute myocardial infarction, and 2158 with stroke were analysed. The proportion of patients prescribed with cardiovascular drugs and days of drug-drug interaction exposure were evaluated. Computerized decision support system significantly increased the proportion of patients with diabetes prescribed with antiplatelet drugs (intervention: +2.7% vs. control: +0.15%; p < 0.001) or lipidlowering drugs (+4.2% vs. +2.8%; p = 0.001). A statistically significant decrease in days of potential interactions has been observed only among patients with stroke (-1.2 vs. -0.5 days/person-year; p = 0.001). In conclusion, computerized decision support system significantly increased the use of recommended cardiovascular drugs in diabetic patients, but it did not influence the exposure to potential interactions. PMID:25210009

Mazzaglia, Giampiero; Piccinni, Carlo; Filippi, Alessandro; Sini, Giovanna; Lapi, Francesco; Sessa, Emiliano; Cricelli, Iacopo; Cutroneo, Paola; Trifirň, Gianluca; Cricelli, Claudio; Caputi, Achille Patrizio

2014-09-10

338

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

ERIC Educational Resources Information Center

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…

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

2013-01-01

339

Multimodality Cardiovascular Molecular Imaging Technology  

PubMed Central

Cardiovascular molecular imaging is a new discipline that integrates scientific advances in both functional imaging and molecular probes to improve our understanding of the molecular basis of the cardiovascular system. These advances are driven by in vivo imaging of molecular processes in animals, usually small animals, and are rapidly moving toward clinical applications. Molecular imaging has the potential to revolutionize the diagnosis and treatment of cardiovascular disease. The 2 key components of all molecular imaging systems are the molecular contrast agents and the imaging system providing spatial and temporal localization of these agents within the body. They must deliver images with the appropriate sensitivity and specificity to drive clinical applications. As work in molecular contrast agents matures and highly sensitive and specific probes are developed, these systems will provide the imaging technologies required for translation into clinical tools. This is the promise of molecular medicine. PMID:20457794

O’Donnell, Matthew; McVeigh, Elliot R.; Strauss, H. William; Tanaka, Atsushi; Bouma, Brett E.; Tearney, Guillermo J.; Guttman, Michael A.; Garcia, Ernest V.

2010-01-01

340

Antioxidant-based therapies for angiotensin II-associated cardiovascular diseases  

PubMed Central

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

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

2013-01-01

341

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

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

Don D. Sin; S. F. Paul Man

2003-01-01

342

Reforming Cardiovascular Care in the United States towards High-Quality Care at Lower Cost with Examples from Model Programs in the State of Michigan.  

PubMed

Despite its status as a world leader in treatment innovation and medical education, a quality chasm exists in American health care. Care fragmentation and poor coordination contribute to expensive care with highly variable quality in the United States. The rising costs of health care since 1990 have had a huge impact on individuals, families, businesses, the federal and state governments, and the national budget deficit. The passage of the Affordable Care Act represents a large shift in how health care is financed and delivered in the United States. The objective of this review is to describe some of the economic and social forces driving health care reform, provide an overview of the Patient Protection and Affordable Care Act (ACA), and review model cardiovascular quality improvement programs underway in the state of Michigan. As health care reorganization occurs at the federal level, local and regional efforts can serve as models to accelerate improvement toward achieving better population health and better care at lower cost. Model programs in Michigan have achieved this goal in cardiovascular care through the systematic application of evidence-based care, the utilization of regional quality improvement collaboratives, community-based childhood wellness promotion, and medical device-based competitive bidding strategies. These efforts are examples of the direction cardiovascular care delivery will need to move in this era of the Affordable Care Act. PMID:25120917

Alyeshmerni, Daniel; Froehlich, James B; Lewin, Jack; Eagle, Kim A

2014-07-01

343

Hemodynamic Energy Dissipation in the Cardiovascular System: Generalized Theoretical Analysis on Disease States  

Microsoft Academic Search

Background We present a fundamental theoretical framework for analysis of energy dissipation in any component of the circulatory system\\u000a and formulate the full energy budget for both venous and arterial circulations. New indices allowing disease-specific subject-to-subject\\u000a comparisons and disease-to-disease hemodynamic evaluation (quantifying the hemodynamic severity of one vascular disease type\\u000a to the other) are presented based on this formalism. Methods

Lakshmi P. Dasi; Kerem Pekkan; Diane de Zelicourt; Kartik S. Sundareswaran; Resmi Krishnankutty; Pedro J. Delnido; Ajit P. Yoganathan

2009-01-01

344

A Systems Biology Approach to Understanding the Mechanisms of Action of Chinese Herbs for Treatment of Cardiovascular Disease  

PubMed Central

Traditional Chinese Medicine (TCM) involves a broad range of empirical testing and refinement and plays an important role in the health maintenance for people all over the world. However, due to the complexity of Chinese herbs, a full understanding of TCM’s action mechanisms is still unavailable despite plenty of successful applications of TCM in the treatment of various diseases, including especially cardiovascular diseases (CVD), one of the leading causes of death. Thus in the present work, by incorporating the chemical predictors, target predictors and network construction approaches, an integrated system of TCM has been constructed to systematically uncover the underlying action mechanisms of TCM. From three representative Chinese herbs, i.e., Ligusticum chuanxiong Hort., Dalbergia odorifera T. Chen and Corydalis yanhusuo WT Wang which have been widely used in CVD treatment, by combinational use of drug absorption, distribution, metabolism and excretion (ADME) screening and network pharmacology techniques, we have generated 64 bioactive ingredients and identified 54 protein targets closely associated with CVD, of which 29 are common targets (52.7%) of the three herbs. The result provides new information on the efficiency of the Chinese herbs for the treatment of CVD and also explains one of the basic theories of TCM, i.e., “multiple herbal drugs can treat one disease”. The predicted potential targets were then mapped to target-disease and target-signal pathway connections, which revealed the relationships of the active ingredients with their potential targets, diseases and signal systems. This means that for the first time, the action mechanism of these three important Chinese herbs for the treatment of CVD is uncovered, by generating and identifying both their active ingredients and novel targets specifically related to CVD, which clarifies some of the common conceptions in TCM, and thus provides clues to modernize such specific herbal medicines. PMID:23202964

Li, Bohui; Xu, Xue; Wang, Xia; Yu, Hua; Li, Xiuxiu; Tao, Weiyang; Wang, Yonghua; Yang, Ling

2012-01-01

345

Cardiovascular and behavioral effects produced by administration of liposome-entrapped GABA into the rat central nervous system.  

PubMed

Liposomes are nanosystems that allow a sustained release of entrapped substances. Gamma-aminobutyric acid (GABA) is the most prevalent inhibitory neurotransmitter of the central nervous system (CNS). We developed a liposomal formulation of GABA for application in long-term CNS functional studies. Two days after liposome-entrapped GABA was injected intracerebroventricularly (ICV), Wistar rats were submitted to the following evaluations: (1) changes in mean arterial pressure (MAP), heart rate (HR) and renal sympathetic nerve activity (RSNA) to ICV injection of bicuculline methiodide (BMI) in anesthetized rats; (2) changes in cardiovascular reactivity to air jet stress in conscious rats; and (3) anxiety-like behavior in conscious rats. GABA and saline-containing pegylated liposomes were prepared with a mean diameter of 200nm. Rats with implanted cannulas targeted to lateral cerebral ventricle (n=5-8/group) received either GABA solution (GS), empty liposomes (EL) or GABA-containing liposomes (GL). Following (48h) central microinjection (2?L, 0.09M and 99g/L) of liposomes, animals were submitted to the different protocols. Animals that received GL demonstrated attenuated response of RSNA to BMI microinjection (GS 48±9, EL 43±9, GL 11±8%; P<0.05), blunted tachycardia in the stress trial (?HR: GS 115±14, EL 117±10, GL 74±9bpm; P<0.05) and spent more time in the open arms of elevated plus maze (EL 6±2 vs. GL 18±5%; P=0.028) compared with GS and EL groups. These results indicate that liposome-entrapped GABA can be a potential tool for exploring the chronic effects of GABA in specific regions and pathways of the central nervous system. PMID:25446344

Vaz, G C; Bahia, A P C O; de Figueiredo Müller-Ribeiro, F C; Xavier, C H; Patel, K P; Santos, R A S; Moreira, F A; Frézard, F; Fontes, M A P

2015-01-29

346

Local and Systemic Cardiovascular Effects from Monochromatic Infrared Therapy in Patients with Knee Osteoarthritis: A Double-Blind, Randomized, Placebo-Controlled Study  

PubMed Central

Infrared (IR) therapy is used for pain relief in patients with knee osteoarthritis (OA). However, IR's effects on the cardiovascular system remain uncertain. Therefore, we investigated the local and systemic cardiovascular effects of monochromatic IR therapy on patients with knee OA in a double-blind, randomized, placebo-controlled study. Seventy-one subjects with knee OA received one session of 40?min of active or placebo monochromatic IR treatment (with power output of 6.24?W, wavelength of 890?nm, power density of 34.7?mW/cm2 for 40?min, total energy of 41.6?J/cm2 per knee per session) over the knee joints. Heart rate, blood pressure, and knee arterial blood flow velocity were periodically assessed at the baseline, during, and after treatment. Data were analyzed by repeated-measure analysis of covariance. Compared to baseline, there were no statistically significant group x time interaction effects between the 2 groups for heart rate (P = 0.160), blood pressure (systolic blood pressure: P = 0.861; diastolic blood pressure: P = 0.757), or mean arterial blood flow velocity (P = 0.769) in follow-up assessments. The present study revealed that although there was no increase of knee arterial blood flow velocity, monochromatic IR therapy produced no detrimental systemic cardiovascular effects. PMID:22792125

Hsieh, Ru-Lan; Liao, Wei-Cheng; Lee, Wen-Chung

2012-01-01

347

A tethering system for direct measurement of cardiovascular function in the caged baboon  

NASA Technical Reports Server (NTRS)

A device suitable for the continuous measurement of physiological activity in large, conscious monkeys has permitted the direct recording of systemic arterial blood pressure and heart rate in caged baboons. The device comprises a lightweight fiberglass backpack, retained in place on the baboon by a thoracic elastic band and shoulder straps, and a flexible stainless steel tether connecting the pack to an electrocannular slip-ring in the top center of the baboon's cage. A chronically indwelling arterial catheter inserted retrograde into the abdominal aorta via the internal iliac artery and connected to a small pressure transducer on the pack provides direct measurement of blood pressure and heart rate. Body fluids can be sampled or drugs administered via an indwelling catheter in the inferior vena cava. Electrical and fluid connections between the fiberglass pack and recording and infusion equipment located outside the cage pass through the flexible tether and remain protected from the subject. The reliability of the tethering system has been demonstrated in physiological, pharmacological, and behavioral experiments with baboons.

Byrd, L. D.

1979-01-01

348

Molecular MRI of the Cardiovascular System in the Post-NSF Era  

PubMed Central

Two new molecular MRI agents have been approved for clinical use within the last 3 years, and a third agent has completed phase-2 clinical trials. A wealth of preclinical data is also emerging on the general safety of many molecular MR imaging agents. In addition, since the guidelines to avoid nephrogenic systemic fibrosis (NSF) were adopted, at most institutions no new cases of NSF have been reported. Nevertheless, in the post-NSF environment, both those developing and using molecular MR imaging agents need to be increasingly aware of safety issues. This awareness should begin with the design of the agent and, even in early preclinical studies, the demonstration of safety and efficacy should both be given high priority. In this review we discuss some of the issues relevant to the design of safe molecular MR imaging agents and highlight the excellent safety profile of those agents that have been used clinically to date. PMID:23504765

Sosnovik, David E.; Caravan, Peter

2013-01-01

349

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

PubMed Central

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

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

350

Effect of age on complexity and causality of the cardiovascular control: comparison between model-based and model-free approaches.  

PubMed

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

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

351

Copernican System Model  

NSDL National Science Digital Library

The Ejs Copernican System model illustrates Copernicus' system of planetary motions. The entire system is centered on the center of Earth's uniform, circular orbit. Sun is placed near, but not at, this center point. The orbit of each planet (other than Earth) consists of a deferent circle, centered on a point some distance from the center (at the eccentric point). Attached to this deferent is the center of a much smaller circle, the epicycle (or epicyclet). The radius of the epicycle is 1/3 the eccentricity of the deferent. The planet moves along the epicycle at a constant angular speed equal to twice the angular speed along the deferent. This model produces retrograde motion and changes in brightness that are always properly correlated with the location of Sun. In this simulation, the planet is assumed to move in the plane of the ecliptic, so its latitude is always zero. You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting "Open Ejs Model" from the pop-up menu item. Ejs Copernican System model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_astronomy_CopernicanSystem.jar file will run the program if Java is installed. Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models. Additional Ejs models for astronomy are available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Timberlake, Todd

2009-08-19

352

[The modeling of physiological systems of organism in 1970-1980s: to history of issue].  

PubMed

The article analyzes models, conditions, types and technologies of imitation modeling under investigations of physiological systems of organism (cardiovascular and respiratory systems) in 1970-1980s. The results of study are presented concerning history of application of imitation model during elaboration of algorithms and programs in clinic for treatment, objective need and advantages of this technique under implementation as an additional tool of physician for proper decision making. PMID:25373304

Serebrianny?, R S

2014-01-01

353

Climate system modeling program  

SciTech Connect

The Climate System Modeling Project is a component activity of NSF's Climate Modeling, Analysis and Prediction Program, supported by the Atmospheric Sciences Program, Geosciences Directorate. Its objective is to accelerate progress toward reliable prediction of global and regional climate changes in the decades ahead. CSMP operates through workshops, support for post-docs and graduate students and other collaborative activities designed to promote interdisciplinary and strategic work in support of the overall objective (above) and specifically in three areas, (1) Causes of interdecadal variability in the climate system, (2) Interactions of regional climate forcing with global processes, and (3) Scientific needs of climate assessment.

NONE

1995-12-31

354

Modeling the earth system  

SciTech Connect

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.

Ojima, D. [ed.

1992-12-31

355

Subchronic Pulmonary Pathology, Iron Overload, and Transcriptional Activity after Libby Amphibole Exposure in Rat Models of Cardiovascular Disease  

PubMed Central

Background: Surface-available iron (Fe) is proposed to contribute to asbestos-induced toxicity through the production of reactive oxygen species. Objective: Our goal was to evaluate the hypothesis that rat models of cardiovascular disease with coexistent Fe overload would be increasingly sensitive to Libby amphibole (LA)-induced subchronic lung injury. Methods: Male healthy Wistar Kyoto (WKY), spontaneously hypertensive (SH), and SH heart failure (SHHF) rats were intratracheally instilled with 0.0, 0.25, or 1.0 mg LA (with saline as the vehicle). We examined bronchoalveolar lavage fluid (BALF) and histological lung sections after 1 week, 1 month, or 3 months for pulmonary biomarkers and pathology. SHHF rats were also assessed at 6 months for pathological changes. Results: All animals developed concentration- and time-dependent interstitial fibrosis. Time-dependent Fe accumulation occurred in LA-laden macrophages in all strains but was exacerbated in SHHF rats. LA-exposed SHHF rats developed atypical hyperplastic lesions of bronchiolar epithelial cell origin at 3 and 6 months. Strain-related baseline differences existed in gene expression at 3 months, with persistent LA effects in WKY but not SH or SHHF rats. LA exposure altered genes for a number of pathways, including inflammation, immune regulation, and cell-cycle control. Cell-cycle control genes were inhibited after LA exposure in SH and SHHF but not WKY rats, whereas tumor suppressor genes were induced only in WKY rats. The inflammatory gene expression also was apparent only in WKY rats. Conclusion: These data show that in Fe-overload conditions, progressive Fe accumulation occurs in fiber-laden macrophages within LA-induced lesions. Fe overload does not appear to contribute to chronic inflammation, and its role in hyperplastic lesion development requires further examination. PMID:21979745

Shannahan, Jonathan H.; Nyska, Abraham; Cesta, Mark; Schladweiler, Mette C.J.; Vallant, Beena D.; Ward, William O.; Ghio, Andrew J.; Gavett, Stephen H.

2011-01-01

356

The deleterious effects of arteriovenous fistula-creation on the cardiovascular system: a longitudinal magnetic resonance imaging study  

PubMed Central

Aim Arteriovenous fistula-formation remains critical for the provision of hemodialysis in end-stage renal failure patients. Its creation results in a significant increase in cardiac output, with resultant alterations in cardiac stroke volume, systemic blood flow, and vascular resistance. The impact of fistula-formation on cardiac and vascular structure and function has not yet been evaluated via “gold standard” imaging techniques in the modern era of end-stage renal failure care. Methods A total of 24 patients with stage 5 chronic kidney disease undergoing fistula-creation were studied in a single-arm pilot study. Cardiovascular magnetic resonance imaging was undertaken at baseline, and prior to and 6 months following fistula-creation. This gold standard imaging modality was used to evaluate, via standard brachial flow-mediated techniques, cardiac structure and function, aortic distensibility, and endothelial function. Results At follow up, left ventricular ejection fraction remained unchanged, while mean cardiac output increased by 25.0% (P<0.0001). Significant increases in left and right ventricular end-systolic volumes (21% [P=0.014] and 18% [P<0.01]), left and right atrial area (11% [P<0.01] and 9% [P<0.01]), and left ventricular mass were observed (12.7% increase) (P<0.01). Endothelial-dependent vasodilation was significantly decreased at follow up (9.0%±9% vs 3.0%±6%) (P=0.01). No significant change in aortic distensibility was identified. Conclusion In patients with end-stage renal failure, fistula-formation is associated with an increase in cardiac output, dilation of all cardiac chambers and deterioration in endothelial function. PMID:25258554

Dundon, Benjamin K; Torpey, Kim; Nelson, Adam J; Wong, Dennis TL; Duncan, Rae F; Meredith, Ian T; Faull, Randall J; Worthley, Stephen G; Worthley, Matthew I

2014-01-01

357

[Effects of erythropoietin on the cardiovascular system and the intradialytic hemodynamic behavior].  

PubMed

The aim of the study was to evaluate, before and after hemodialysis (HD), the effects of partial correction of anemia with erythropoietin on: cardiac index (CI), stroke index (SI), heart rate (HR), ventricular ejection index (EVI), mean arterial pressure (PAM) and systemic vascular resistance index (SVRI). Cardiac parameters were gathered by means of transthoracic bioimpedance (BoMed). Twelve patients (6 M, 6 F) aged 50.6 +/- 5 years, on HD for 92.8 +/- 15.9 months, were studied twice (basal, end of follow-up). Before rHuEPO therapy, 6 patients had a "pathologic" cardiac response to HD (defined as an increase of CI despite the reduction of pre-load). After rHuEPO, 5 out of 6 patients with a "pathologic" response reverted to a "normal" response, and 1 hypertensive patient from a "normal" to a "pathologic" response. The EVI, CI and SI of patients with "pathological" response significantly improved after rHuEPO as compared with pre rHuEPO values (EVI 1.36 +/- 0.14 vs 1.07 +/- 0.08, p = 0.023; CI 3.18 +/- 0.24 vs 1.78 +/- 0.27, p less than 0.01; SI 43 +/- 3.7 vs 24 +/- 3.8, p less than 0.01). In conclusion, partial correction of anemia with rHuEPO induces an improvement of myocardial performance, without significant hemodynamic adverse effects. Our results suggest also that anemia could play a significant role in the pathogenesis of myocardial disfunction in HD patients. PMID:1817333

Quarello, F; Martina, G; Beltrame, G; Boero, R; Forneris, G; Borca, M; Iadarola, G M; Stramignoni, E; Maffei, S; Piccoli, G

1991-01-01

358

Cardiovascular Variability Analysis under Gradually Guided Breathing Protocol  

Microsoft Academic Search

Slow and regular breathing can make beneficial effects on cardiovascular system and autonomic nerve system. Many researches studied the cardiovascular variabilities under paced breathing rate of 0.25 Hz and 0.1 Hz, but few quantitative data are available describing the relationships between the cardiovascular variables during the slow and regular breathing procedure, and mechanism of the beneficial effects behind the slow

Zhengbo Zhang; Weidong Wang; Buqing Wang; Hao Wu; Qing Ang; Hongyun Liu; Yukai Zhang

2009-01-01

359

[Stress and cardiovascular disease].  

PubMed

Risk factors of cardiovascular disease (CVD) have been studied intensely since the 1950s. Results on stress as a risk factor for CVD have been inconsistent, but mainly positive. The risk is mediated through lifestyle, but more direct physiological mechanisms (e.g. autonomous nervous system and hypothalamic-pituitary-adrenal axis) are also found. Personality and general coping resources influence stress-appraisal, stress-coping and stress-response. Future studies should integrate stress as a cause (stressor), as a subjective reaction (perception), and as a physiological reaction in the same longitudinal studies with repeated measures. PMID:22277363

Ebstrup, Jeanette Frost; Jřrgensen, Torben

2012-01-23

360

PPAR? Activity in Cardiovascular Diseases: A Potential Pharmacological Target  

PubMed Central

Activation of peroxisome proliferator-activated receptors (PPARs), and particularly of PPAR? and PPAR?, using selective agonists, is currently used in the treatment of metabolic diseases such as hypertriglyceridemia and type 2 diabetes mellitus. PPAR? and PPAR? anti-inflammatory, antiproliferative and antiangiogenic properties in cardiovascular cells were extensively clarified in a variety of in vitro and in vivo models. In contrast, the role of PPAR? in cardiovascular system is poorly understood. Prostacyclin, the predominant prostanoid released by vascular cells, is a putative endogenous agonist for PPAR?, but only recently PPAR? selective synthetic agonists were found, improving studies about the physiological and pathophysiological roles of PPAR? activation. Recent reports suggest that the PPAR? activation may play a pivotal role to regulate inflammation, apoptosis, and cell proliferation, suggesting that this transcriptional factor could become an interesting pharmacological target to regulate cardiovascular cell apoptosis, proliferation, inflammation, and metabolism. PMID:19325917

Tesse, Angela; Andriantsitohaina, Ramaroson; Ragot, Thierry

2009-01-01

361

Non-invasive assessment of Alterations in Cardiovascular regulation and function and susceptibility to ventricular arrhythmias resulting from microgravity exposure  

NASA Astrophysics Data System (ADS)

Alterations in cardiovascular regulation and function that occur during and after space flight have been reported. These alterations are manifested, for example, by reduced orthostatic tolerance upon reentry to the earth's gravity from space. However, the precise physiologic mechanisms responsible for these alterations remain to be fully elucidated. Perhaps as a result, fully effective countermeasures have yet to be developed. The National Space Biomedical Research Institute Cardiovascular Alterations Team is currently conducting a head-down tilt bed rest study in Boston. These studies involve the application of two powerful new methodologies developed at the NASA Center for Quantitative Cardiovascular Physiology, Modeling and Data Analysis at the Massachusetts Institute of Technology-cardiovascular system identification and T Wave Alternans analysis-for the study of the effects of simulated microgravity on the cardiovascular system. This study is being used as a basis for developing effective countermeasures against microgravity induced orthostatic hypotension and ventricular arrhythmias. .

Ramsdell, Craig D.; Sundby, Grete H.; Sherman, Derin; Maa, Ming; Baskin, Jacquelyn L.; Williams, Gordon H.; Cohen, Richard J.

2000-01-01

362

INTEGRATED GLOBAL SYSTEM MODEL  

EPA Science Inventory

The MIT Integrated Global System Model (IGSM) is designed for simulating the global environmental changes that may arise as a result of anthropogenic causes, the uncertainties associated with the projected changes, and the effect of proposed policies on such changes. As described...

363

Non-antibacterial tetracyclines modulate mediators of periodontitis and atherosclerotic cardiovascular disease: A mechanistic link between local and systemic inflammation  

Microsoft Academic Search

Periodontitis, one of the most common chronic inflammatory diseases afflicting man, is increasingly being recognized as a risk factor for atherosclerotic cardiovascular disease (ASCVD). Non-antimicrobial tetracyclines are known to have inhibitory effects on inflammatory mediators and effector molecules, including cytokines and matrix metalloproteinases (MMPs), associated with both diseases. In this paper, we discuss the evidence that doxycycline and related non-antibiotic

Ying Gu; Hsi-Ming Lee; Timo Sorsa; Aino Salminen; Maria E. Ryan; Marvin J. Slepian; Lorne M. Golub

2011-01-01

364

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

E-print Network

Laser Doppler flowmetry signals to quantify effects of isoflurane on the peripheral cardiovascular; published online 27 December 2007 The optical Doppler effect resulting from interactions between laser light increases. These findings demonstrate the usefulness of the optical Doppler effect in physiological

Chapeau-Blondeau, François

365

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 cardiovascular disease (CVD) and diabetes. Heart diseases and stroke are ...

366

Understanding cardiovascular disease  

MedlinePLUS

Cardiovascular disease is the broad term for problems with the heart and blood vessels. These problems are often ... and tissue. High blood pressure (hypertension) is a cardiovascular disease that can lead to other problems, such as ...

367

Closed-loop minimal model analysis of the cardiovascular response to transient arousal from sleep in healthy humans  

Microsoft Academic Search

In a previous work we reported discrepancies in the cardiovascular response to arousal from NREM sleep between OSAS patients and healthy controls. The long lasting cardiac sympathetic increase observed in normals was not present in the OSAS group, whereas the peripheral vasculature reaction was similar between the two groups. Analysis of REM arousal revealed that there was a similar temporary

A. Blasi; J. Jo; E. Valladares; R. Juarez; A. Baydur; M. C. K. Khoo

2004-01-01

368

Cardiovascular Disease and Cancer: Student Awareness Activities.  

ERIC Educational Resources Information Center

Awareness activities pertaining to cancer and cardiovascular disease are presented as a supplement for high school science classes. The exercises can be used to enrich units of study dealing with the circulatory system, the cell, or human diseases. Eight activities deal with the following topics: (1) cardiovascular disease risk factors; (2)…

Meyer, James H., Comp.

369

Systemic vasculopathy with altered vasoreactivity in a transgenic mouse model of scleroderma  

Microsoft Academic Search

INTRODUCTION: Vasculopathy, including altered vasoreactivity and abnormal large vessel biomechanics, is a hallmark of systemic sclerosis (SSc). However, the pathogenic link with other aspects of the disease is less clear. To assess the potential role of transforming growth factor beta (TGF-?) overactivity in driving these cardiovascular abnormalities, we studied a novel transgenic mouse model characterized by ligand-dependent activation of TGF-?

Emma C Derrett-Smith; Audrey Dooley; Korsa Khan; Xu Shi-wen; David J Abraham; Christopher P Denton

2010-01-01

370

Short-Term Complexity of Cardiac Autonomic Control during Sleep: REM as a Potential Risk Factor for Cardiovascular System in Aging  

PubMed Central

Introduction Sleep is a complex phenomenon characterized by important modifications throughout life and by changes of autonomic cardiovascular control. Aging is associated with a reduction of the overall heart rate variability (HRV) and a decrease of complexity of autonomic cardiac regulation. The aim of our study was to evaluate the HRV complexity using two entropy-derived measures, Shannon Entropy (SE) and Corrected Conditional Entropy (CCE), during sleep in young and older subjects. Methods A polysomnographic study was performed in 12 healthy young (21.1±0.8 years) and 12 healthy older subjects (64.9±1.9 years). After the sleep scoring, heart period time series were divided into wake (W), Stage 1–2 (S1-2), Stage 3–4 (S3-4) and REM. Two complexity indexes were assessed: SE(3) measuring the complexity of a distribution of 3-beat patterns (SE(3) is higher when all the patterns are identically distributed and it is lower when some patterns are more likely) and CCEmin measuring the minimum amount of information that cannot be derived from the knowledge of previous values. Results Across the different sleep stages, young subjects had similar RR interval, total variance, SE(3) and CCEmin. In the older group, SE(3) and CCEmin were reduced during REM sleep compared to S1-2, S3-4 and W. Compared to young subjects, during W and sleep the older subjects showed a lower RR interval and reduced total variance as well as a significant reduction of SE(3) and CCEmin. This decrease of entropy measures was more evident during REM sleep. Conclusion Our study indicates that aging is characterized by a reduction of entropy indices of cardiovascular variability during wake/sleep cycle, more evident during REM sleep. We conclude that during aging REM sleep is associated with a simplification of cardiac control mechanisms that could lead to an impaired ability of the cardiovascular system to react to cardiovascular adverse events. PMID:21544202

Chellappa, Sarah L.; Casali, Karina Rabello; Porta, Alberto; Montano, Nicola

2011-01-01

371

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

PubMed Central

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

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

372

Genetic analysis of the cardiac methylome at single nucleotide resolution in a model of human cardiovascular disease.  

PubMed

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

Johnson, Michelle D; Mueller, Michael; 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

2014-12-01

373

Internal Medicine Cardiovascular Medicine ------------------------------------------------------------------------------  

E-print Network

methods, and novel therapeutic measures of various cardiovascular diseases (ischemic heart disease, heart of cardiovascular diseases ·Imaging techniques (echocardiography, MRI, CT, RI, NOGA) in cardiovas- cular diseases polymorphisms and risk factors in cardiovascular disease ·Differentiation of smooth muscle cells

Miyashita, Yasushi

374

UK Centre for Cardiovascular  

E-print Network

of cardiovascular disease and diabetes to improve human life It is an important team effort between the UniversityT AGAINST hEART DISEASE 7 #12;CARDIOVASCULAR DISEASE AND DIAbETES IS A GLObAL ChALLENGE Diabetes-centre imaging trials. Our work showing the superiority of MRI for diagnosing cardiovascular disease has

Berzins, M.

375

Sixth Annual Cardiovascular  

E-print Network

Feinberg School of Medicine EarthphotoscourtesyofNASA #12;CARDIOVASCULAR DISEASE is still the leading cause cardiovascular disease as their major health problem and thus fail to partner with their healthcare providers in cardiovascular disease. Recognition of these differences requires communication of this information to women

MacIver, Malcolm A.

376

FRONTIERS IN CARDIOVASCULAR  

E-print Network

FRONTIERS IN CARDIOVASCULAR SCIENCE SPON S ORED BY LOCATION/TIME Li Ka Shing Center for Learning at 11:45 a.m. TUESDAy, SEpTEmbER 11, 2012 Raising HDL: Will it Work to Prevent Cardiovascular Events-14, 2012 CVI AnnuAl MeMber retreAt Robert Harrington, MD Stanford University Cardiovascular Clinical

Puglisi, Joseph

377

Assistant, Associate & Full Professor Division of Cardiovascular Medicine  

E-print Network

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

Quake, Stephen R.

378

Down Syndrome: A Cardiovascular Perspective  

ERIC Educational Resources Information Center

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…

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

379

Down syndrome: a cardiovascular perspective  

Microsoft Academic Search

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 skilful management of cardiac problems in patients with Down syndrome. Epidemiology of congenital heart defects, cardiovascular aspects and thyroid-related cardiac impairment in patients with Down syndrome will be discussed.

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

2009-01-01

380

Cardiovascular risk factors among Chamorros  

Microsoft Academic Search

BACKGROUND: Little is known regarding the cardiovascular disease risk factors among Chamorros residing in the United States. METHODS: The Chamorro Directory International and the CDC's Behavioral Risk Factor Surveillance System Questionnaire (BRFSS) were used to assess the health related practices and needs of a random sample of 228 Chamorros. RESULTS: Inactivity, hypertension, elevated cholesterol and diabetes mellitus were more prevalent

Binh Chiem; Victoria Nguyen; Phillis L Wu; Celine M Ko; Lee Ann Cruz; Georgia Robins Sadler

2006-01-01

381

Significant associations between hemostatic/fibrinolytic systems and accumulation of cardiovascular risk factors in Japanese elementary schoolchildren.  

PubMed

The aim of this study was to establish the reference values of hemostatic/fibrinolytic markers and investigate their relationship with physical constitution and cardiovascular risk factors in a normal schoolchildren population. This study comprised 148 healthy Japanese children aged 9-10 years (males 73; females 75). We performed laboratory tests including blood levels of leptin, high-sensitive C-reactive protein (hs-CRP), hemostatic and fibrinolytic markers [plasminogen activator inhibitor 1 (PAI-1), coagulation factor VII (FVII), coagulation factor X (FX), fibrinogen (Fbg), protein C, protein S], as well as common biochemical markers in the morning after an overnight fast. We investigated the mean, 10th, 50th and 90th percentile values of these markers. All parameters were compared between two groups, that is those with body mass index (BMI) 90th percentile or higher and BMI less than 90th percentile, and between subgroups based on the number of cardiovascular risk factors. Multiple-linear regression was used to assess associations between these hematological parameters and the components related to metabolic syndrome (MetS). Alanine aminotransferase (ALT), uric acid, leptin, hs-CRP, and all hemostatic/fibrinolytic markers (PAI-1, FVII, FX, Fbg, protein C, protein S) tested were significantly higher in the group with BMI 90th percentile or higher, and increased with accumulation of cardiovascular risk factors. Multiple-linear regression analysis showed that these values were associated with one or more components related to MetS. Reference values of hemostatic/fibrinolytic markers in Japanese schoolchildren were obtained. Many hemostatic/fibrinolytic markers showed significant association with BMI and accumulation of cardiovascular risk factors in normal Japanese schoolchildren. PMID:25185676

Lin, Lisheng; Horigome, Hitoshi; Kato, Yoshiaki; Kikuchi, Toshihiro; Nakahara, Satoko; Sumazaki, Ryo

2015-01-01

382

An intelligent mobile cardiovascular monitoring device based on pulse wave  

Microsoft Academic Search

Originated from the pulse diagnosis of Traditional Chinese Medicine (TCM) and promoted by the advanced signal processing technologies, the research on hemodynamic analysis of pulse wave makes it promising to develop the novel mobile cardiovascular monitoring device, which can comprehensively assess the health condition of cardiovascular system. Here an intelligent cardiovascular monitoring device, implemented on an ARM-based mobile platform, is

Bing-Nan Li; Ming-Chui Dong; Vai Mang; Mak Peng Un

2005-01-01

383

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

PubMed Central

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

Onal, Bulent

2013-01-01

384

Arsenic in public water supplies and cardiovascular mortality in Spain  

SciTech Connect

Background: High-chronic arsenic exposure in drinking water is associated with increased cardiovascular disease risk. At low-chronic levels, as those present in Spain, evidence is scarce. In this ecological study, we evaluated the association of municipal drinking water arsenic concentrations during the period 1998-2002 with cardiovascular mortality in the population of Spain. Methods: Arsenic concentrations in drinking water were available for 1721 municipalities, covering 24.8 million people. Standardized mortality ratios (SMRs) for cardiovascular (361,750 deaths), coronary (113,000 deaths), and cerebrovascular (103,590 deaths) disease were analyzed for the period 1999-2003. Two-level hierarchical Poisson models were used to evaluate the association of municipal drinking water arsenic concentrations with mortality adjusting for social determinants, cardiovascular risk factors, diet, and water characteristics at municipal or provincial level in 651 municipalities (200,376 cardiovascular deaths) with complete covariate information. Results: Mean municipal drinking water arsenic concentrations ranged from <1 to 118 {mu}g/L. Compared to the overall Spanish population, sex- and age-adjusted mortality rates for cardiovascular (SMR 1.10), coronary (SMR 1.18), and cerebrovascular (SMR 1.04) disease were increased in municipalities with arsenic concentrations in drinking water >10 {mu}g/L. Compared to municipalities with arsenic concentrations <1 {mu}g/L, fully adjusted cardiovascular mortality rates were increased by 2.2% (-0.9% to 5.5%) and 2.6% (-2.0% to 7.5%) in municipalities with arsenic concentrations between 1-10 and>10 {mu}g/L, respectively (P-value for trend 0.032). The corresponding figures were 5.2% (0.8% to 9.8%) and 1.5% (-4.5% to 7.9%) for coronary heart disease mortality, and 0.3% (-4.1% to 4.9%) and 1.7% (-4.9% to 8.8%) for cerebrovascular disease mortality. Conclusions: In this ecological study, elevated low-to-moderate arsenic concentrations in drinking water were associated with increased cardiovascular mortality at the municipal level. Prospective cohort studies with individual measures of arsenic exposure, standardized cardiovascular outcomes, and adequate adjustment for confounders are needed to confirm these ecological findings. Our study, however, reinforces the need to implement arsenic remediation treatments in water supply systems above the World Health Organization safety standard of 10 {mu}g/L.

Medrano, Ma Jose, E-mail: pmedrano@isciii.es [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain); Boix, Raquel; Pastor-Barriuso, Roberto [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain)] [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain); Palau, Margarita [Subdireccion General de Sanidad Ambiental y Salud Laboral, Direccion General de Salud Publica y Sanidad Exterior, Ministerio de Sanidad y Politica Social, Madrid (Spain)] [Subdireccion General de Sanidad Ambiental y Salud Laboral, Direccion General de Salud Publica y Sanidad Exterior, Ministerio de Sanidad y Politica Social, Madrid (Spain); Damian, Javier [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain)] [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain); Ramis, Rebeca [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain) [Centro Nacional de Epidemiologia, Instituto de Salud Carlos III, Sinesio Delgado 6, 28029 Madrid (Spain); CIBER en Epidemiologia y Salud Publica (CIBERESP), Madrid (Spain); Barrio, Jose Luis del [Departamento de Salud Publica, Universidad Rey Juan Carlos, Madrid (Spain)] [Departamento de Salud Publica, Universidad Rey Juan Carlos, Madrid (Spain); Navas-Acien, Ana [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States) [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States); Department of Epidemiology, Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD (United States)

2010-07-15

385

Comparison of equilibrium radionuclide ventriculography with cardiovascular magnetic resonance for assessing the systemic right ventricle after Mustard or Senning procedures for complete transposition of the great arteries.  

PubMed

We assessed the utility of equilibrium radionuclide ventriculography for assessing function of the systemic right ventricle by comparing it with cardiovascular magnetic resonance (CMR) in subjects who had undergone the Mustard or Senning operations for complete transposition of the great arteries. The 95% limits of agreement for right ventricular ejection fraction by the 2 techniques were 15.8% to -16.0%, demonstrating that equilibrium radionuclide ventriculography has good agreement with CMR and provides a good alternative in cases in which CMR is not available or appropriate. PMID:12943898

Hornung, Tim S; Anagnostopoulos, Constantinos; Bhardwaj, Pushan; Kilner, Philip J; Davlouros, Periklis A; Bailey, James; Francis, Jane M; Pennell, Dudley J; Underwood, S Richard; Gatzoulis, Michael A

2003-09-01

386

Semaphorins in cardiovascular medicine.  

PubMed

During organogenesis, patterning is primarily achieved by the combined actions of morphogens. Among these, semaphorins represent a general system for establishing the appropriate wiring architecture of biological nets. Originally discovered as evolutionarily conserved steering molecules for developing axons, subsequent studies on semaphorins expanded their functions to the cardiovascular and immune systems. Semaphorins participate in cardiac organogenesis and control physiological vasculogenesis and angiogenesis, which result from a balance between pro- and anti-angiogenic signals. These signals are altered in several diseases. In this review, we discuss the role of semaphorins in vascular biology, emphasizing the mechanisms by which these molecules control vascular patterning and lymphangiogenesis, as well as in genetically inherited and degenerative vascular diseases. PMID:25154329

Corŕ, Davide; Astanina, Elena; Giraudo, Enrico; Bussolino, Federico

2014-10-01

387

User Models in Dialog Systems  

Microsoft Academic Search

This chapter surveys the field of user modeling in artificial intelligence dialog systems. First, reasons why user modeling has become so important in the last few years are pointed out, and definitions are proposed for the terms 'user model' and 'user modeling component'. Research within and outside of artificial intelligence which is related to user modeling in dialog systems is

Wolfgang Wahlster; Alfred Kobsa

1988-01-01

388

Preliminary Study of Cardiovascular Manifestations and Cardiac Severity Scale in 58 Patients with Systemic Sclerosis in Iran Using the Medsger Scale  

PubMed Central

Background: Cardiac involvement in systemic sclerosis (SSc) is more prevalent than previously thought. In this study, the frequency and severity of cardiovascular involvement were assessed in SSc patients referred to Firouzgar Hospital. Methods: Fifty-eight patients with SSc, selected from the data bank of SSc patients, were reviewed for the frequency and severity of 8 organ involvements in this case series. The preliminary severity scale, published by international SSc study groups, was employed for the determination of the severity grade in the cardiovascular system. In the cardiac scoring scale, grade 0 represents normal heart (no cardiac involvement), grade 1 denotes mild involvement [electrocardiography (ECG) conduction defect and a left ventricular ejection fraction (LVEF) of 45–49%)], grade 2 signifies moderate involvement (arrhythmia, LVEF = 40–44%), grade 3 indicates severe involvement (LVEF <40%)], and grade 4 stands for end stage (congestive heart failure and arrhythmia requiring treatment). Results: In this study, 24 (41.4%) patients were in the diffuse cutaneous (dcSSc) subset. The female to male ratio was 10.5:1, and the mean duration from symptom onset to diagnosis was 7.35 years for the dcSSc subset and 8.41 years for the limited cutaneous (lcSSc) subset of disease, there being no significant difference. Cardiac involvement in this series was seen in 13 (22.4%) cases; and there was no significant difference in terms of frequency and severity between the two disease subgroups (p value = 0.96 and p value = 0.46 respectively). Conclusion: Our findings showed that the cardiac involvement in this series was infrequent and that there was no significant difference in the severity of cardiovascular involvement between the two subtypes of SSc in the late stage of the disease. PMID:23074562

Poormoghim, Hadi; Poorkarim, Mohamad Ali; Lakeh, Maziar Moradi; Heshmati, Behnaz Nozary; Almasi, Simin; Hakim, Mojtaba

2010-01-01

389

Cardiovascular lymphoscintigraphy  

SciTech Connect

The technique of lymphoscintigraphy when applied to the heart and blood vessels correlates well with results of anatomic investigations of arterial and cardiac lymphatic vessels reported in the literature. Five dogs and eight rabbits underwent lymphoscintigraphy of the heart and aorta, as well as the iliac, femoral, and tibial arteries. After surgical exposure, approximately 500 microCi of /sup 99m/Tc-labelled antimony sulfide was injected into the myocardium or the adventitial-medial plane of an artery. The colloid particle size of 4 to 12 m mu causes resorption and transport only via the lymphatic vessels. Twenty-one preparations were imaged from 2 to 48 hours after administration. This method provides a functional demonstration that the tibial and femoral arteries of both species are invested with lymphatics. The first echelon of lymph nodes which drain muscular arteries are imaged within 2 hours. Regional lymph nodes could not be seen to drain the aorta or iliac arteries. Anterior left ventricular myocardial injection in the dog showed a single cardiac lymph node. This drainage pattern has been described previously by other investigators. In the rabbit a similarly placed injection visualized a group of regional cardiac nodes. Ligation of the collecting ducts afferent to the cardiac node in the dog prevented removal of the isotope from the heart at 3, 6, and 9 hours. At 24 hours the liver and spleen were imaged, the radiocolloid gaining entrance to the blood vascular system presumably via myocardial lymphaticovenous anastomoses. Lymphoscintigraphy reflects physiologic processes such as lymph transport, filtration, and reticuloendothelial function. It defines regional patterns of cardiac and arterial lymph drainage. It can confirm experimentally produced impairment of lymph drainage from a defined area of tissue. Lymphoscintigraphy should be useful in the investigation of the significance of lymph drainage to diseases of the heart and blood vessels.

Castronuovo, J.J. Jr.; Lopez-Majano, V.; Flanigan, P.; Schuler, J.J.; Jonasson, O.

1983-08-01

390

Cardiovascular adverse effects of newer antidepressants.  

PubMed

Newer antidepressants that are more selective in their neurotransmitter effects include the selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and others (agomelatine, bupropion, mirtazapine, reboxetine, vilazodone, vortioxetine). This article systematically reviews data from a variety of sources regarding the potential adverse effects of these medications on various cardiovascular parameters. Potential biochemical mechanisms by which these antidepressants may adversely affect the cardiovascular system are also discussed. Antidepressants that are associated with higher cardiovascular risk (SNRIs, reboxetine), lower risk (SSRIs), and without current evidence of cardiovascular risk (agomelatine, mirtazapine, vilazodone, vortioxetine) are identified. The FDA's recommendations regarding citalopram are organized and summarized, and situations with higher risk of cardiovascular adverse effects are identified. PMID:24738823

Mago, Rajnish; Tripathi, Neeta; Andrade, Chittaranjan

2014-05-01

391

Development and Validation of a Coronary Risk Prediction Model for Older U.S. and European Persons in the Cardiovascular Health Study and the Rotterdam Study  

PubMed Central

Background Risk scores for prediction of coronary heart disease (CHD) in older adults are needed. Objective To develop a sex-specific CHD risk prediction model for older adults that accounts for competing risks for death. Design 2 observational cohort studies, using data from 4946 participants in the Cardiovascular Health Study (CHS) and 4303 participants in the Rotterdam Study (RS). Setting Community settings in the United States (CHS) and Rotterdam, the Netherlands (RS). Participants Persons aged 65 years or older who were free of cardiovascular disease. Measurements A composite of nonfatal myocardial infarction and coronary death. Results During a median follow-up of 16.5 and 14.9 years, 1166 CHS and 698 RS participants had CHD events, respectively. Deaths from noncoronary causes largely exceeded the number of CHD events, complicating accurate CHD risk predictions. The prediction model had moderate ability to discriminate between events and nonevents (c-statistic, 0.63 in both U.S. and European men and 0.67 and 0.68 in U.S. and European women). The model was well-calibrated; predicted risks were in good agreement with observed risks. Compared with the Framingham point scores, the prediction model classified elderly U.S. persons into higher risk categories but elderly European persons into lower risk categories. Differences in classification accuracy were not consistent and depended on cohort and sex. Adding newer cardiovascular risk markers to the model did not substantially improve performance. Limitation The model may be less applicable in nonwhite populations, and the comparison Framingham model was not designed for adults older than 79 years. Conclusion A CHD risk prediction model that accounts for deaths from noncoronary causes among older adults provided well-calibrated risk estimates but was not substantially more accurate than Framingham point scores. Moreover, adding newer risk markers did not improve accuracy. These findings emphasize the difficulties of predicting CHD risk in elderly persons and the need to improve these predictions. Primary Funding Source National Heart, Lung, and Blood Institute; National Institute of Neurological Disorders and Stroke; The Netherlands Organisation for Scientific Research; and the Netherlands Organisation for Health Research and Development. PMID:22986376

Koller, Michael T.; Leening, Maarten J.G.; Wolbers, Marcel; Steyerberg, Ewout W.; Hunink, M.G. Myriam; Schoop, Rotraut; Hofman, Albert; Bucher, Heiner C.; Psaty, Bruce M.; Lloyd-Jones, Donald M.; Witteman, Jacqueline C.M.

2013-01-01

392

Cardiovascular reactivity, stress, and physical activity  

PubMed Central

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

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

2013-01-01

393

Obesity and cardiovascular disease.  

PubMed

Cardiovascular disease is the most common cause of mortality in rich countries and today it has the same meaning for health care as the epidemics of past centuries had for medicine in earlier times: 50% of the population in these countries die of cardiovascular disease. The amount of cardiovascular disease is also increasing in the developing countries together with economic growth. By 2015 one in three deaths will globally be due to cardiovascular diseases. Coronary heart disease is a chronic disease that starts in childhood, even if the symptoms first occur in the middle age. The risks for coronary heart disease are well-known: lipid disorders, especially high serum LDL-cholesterol concentration, high blood pressure, tobacco smoking, obesity, diabetes, male gender and physical inactivity. Obesity is both an independent risk factor for cardiovascular disease but is also closely connected with several other risk factors. This review focuses on the connection between overweight or obesity and cardiovascular disease. PMID:25387321

Jokinen, E

2015-03-01

394

The insulin-like growth factor I system: Physiological and pathophysiological implication in cardiovascular diseases associated with metabolic syndrome.  

PubMed

Metabolic syndrome is a cluster of risk factors including obesity, dyslipidemia, hypertension, and insulin resistance. A number of theories have been speculated for the pathogenesis of metabolic syndrome including impaired glucose and lipid metabolism, lipotoxicity, oxidative stress, interrupted neurohormonal regulation and compromised intracellular Ca(2+) handling. Recent evidence has revealed that adults with severe growth hormone (GH) and insulin-like growth factor I (IGF-1) deficiency such as Laron syndrome display increased risk of stroke and cardiovascular diseases. IGF-1 signaling may regulate contractility, metabolism, hypertrophy, apoptosis, autophagy, stem cell regeneration and senescence in the heart to maintain cardiac homeostasis. An inverse relationship between plasma IGF-1 levels and prevalence of metabolic syndrome as well as associated cardiovascular complications has been identified, suggesting the clinical promises of IGF-1 analogues or IGF-1 receptor activation in the management of metabolic and cardiovascular diseases. However, the underlying pathophysiological mechanisms between IGF-1 and metabolic syndrome are still poorly understood. This mini-review will discuss the role of IGF-1 signaling cascade in the prevalence of metabolic syndrome in particular the susceptibility to overnutrition and sedentary life style-induced obesity, dyslipidemia, insulin resistance and other features of metabolic syndrome. Special attention will be dedicated in IGF-1-associated changes in cardiac responses in various metabolic syndrome components such as insulin resistance, obesity, hypertension and dyslipidemia. The potential risk of IGF-1 and IGF-1R stimulation such as tumorigenesis is discussed. Therapeutic promises of IGF-1 and IGF-1 analogues including mecasermin, mecasermin rinfabate and PEGylated IGF-1 will be discussed. PMID:25541285

Ren, Jun; Anversa, Piero

2015-02-15

395

Modeling the Effects of Indoor Passive Smoking at Home, Work, or Other Households on Adult Cardiovascular and Mental Health: The Scottish Health Survey, 2008–2011  

PubMed Central

Passive smoking has contributed increased risks of cardiovascular disease, mental health, and mortality, but the cumulative effects from work or other households were less studied. Therefore, it was aimed to model the effects of indoor passive smoking from own home, work, and other households in a country-wide, population-based setting. Data in the Scottish Health Survey between 2008 and 2011 after the law banning smoking in public places were analyzed. Information including demographics, lifestyle factors, and self-reported cardiovascular disease and mental health was obtained by household interview. Analyses included chi-square test and survey-weighted logistic regression modeling. After full adjustment, it was observed that being exposed to indoor passive smoking, in particular in more than two places of exposure, was significantly associated with risks of stroke, angina, heart attack, abnormal heart rhythms, and GHQ ? 12. The significance remained for angina, GHQ ? 12 and probably heart attack in never smokers. The cumulative risks also impacted on sleep problems, self-recognition, making decisions, self-confidence, under strain constantly, depressed, happiness and self-worth. The significance remained for sleep problems, self-confidence, under strain constantly, depressed, and happiness in never smokers. Elimination of indoor passive smoking from different sources should still be a focus in future public health programs. PMID:24633145

Shiue, Ivy

2014-01-01

396

Research opportunities in cardiovascular deconditioning, phase 1  

NASA Technical Reports Server (NTRS)

The deconditioning of the cardiovascular system that occurs during spaceflight, NASA's current and projected research program, and the conclusions and suggestions of the ad hoc Working Group are summarized.

Levy, M. N. (editor); Talbot, J. M. (editor)

1983-01-01

397

Home and Clinical Cardiovascular Care Center (H4C): a Framework for Integrating Body Sensor Networks and QTRU Cryptography System.  

PubMed

Quick responds to heart attack patients before arriving to hospital is a very important factor. In this paper, a combined model of Body Sensor Network and Personal Digital Access using QTRU cipher algorithm in Wifi networks is presented to efficiently overcome these life threatening attacks. The algorithm for optimizing the routing paths between sensor nodes and an algorithm for reducing the power consumption are also applied for achieving the best performance by this model. This system is consumes low power and has encrypting and decrypting processes. It also has an efficient routing path in a fast manner. PMID:24252988

Zakerolhosseini, Ali; Sokouti, Massoud; Pezeshkian, Massoud

2013-01-01

398

Tobacco and Cardiovascular Health.  

PubMed

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

Mainali, Prajeena; Pant, Sadip; Rodriguez, Alexis Phillip; Deshmukh, Abhishek; Mehta, Jawahar L

2014-09-16

399

Cardiovascular involvement in leptospirosis.  

PubMed

Cardiovascular involvement was studied in 50 patients with serologically proved leptospirosis. Twelve (24%) patients had dyspnoea and 18 (36%) had transient hypotension during the illness. None of them had cardiac enlargement, development of new murmur or pericardial rub. Various electrocardiographic abnormalities occurred in 70 percent of patients. Atrial fibrillation was the most common major arrhythmia (14%). Conduction system abnormalities were seen in 36 percent of patients. T-wave changes were observed in 30 percent of patients. Left ventricular function as assessed by echocardiography and Doppler examination was normal. Three (6%) patients died due to renal failure. In conclusion, even though ECG abnormalities were frequently seen in leptospirosis, there was no data to support associated left ventricular dysfunction. Dyspnoea and hypotension occurring in patients of leptospirosis must be due to a noncardiac mechanism. PMID:9062020

Rajiv, C; Manjuran, R J; Sudhayakumar, N; Haneef, M

1996-01-01

400

Certain peculiarities of the functioning of the cardiovascular system in bedrest conditions during horizontal and antiorthostatic body positions  

NASA Technical Reports Server (NTRS)

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.

1978-01-01

401

Cardiomyopathy in murine models of systemic sclerosis.  

PubMed

Objectives. Cardiomyopathy has emerged as a leading cause of death in systemic sclerosis (SSc). However, the pathogenesis of SSc-related cardiomyopathy is poorly understood and new therapies as well as platforms for testing are needed. Here, we aimed to characterize the histopathological features of cardiomyopathy in SSc patients and in common mouse models of SSc. Methods. The histopathological features in myocardial tissues of five patients with SSc and five controls matched for sex, age and cardiovascular risk factors were evaluated and compared to those of three common mouse models of SSc with systemic manifestations: Fra-2 transgenic (Fra-2 tg) mice, mice with sclerodermatous chronic Graft versus Host disease (cGvHD) and tight skin 1 (Tsk-1) mice. Results: Myocardial tissues of SSc patients without clinically manifest cardiac involvement showed endothelial cell apoptosis with reduced capillary density, perivascular inflammation, myofibroblast differentiation and accumulation of collagen. The cGvHD and Tsk-1 models displayed only selected features of SSc-related cardiomyopathy. However, myocardial tissue of Fra-2 tg mice mimicked all features of SSc-related cardiomyopathy and also demonstrated comparable vascular, inflammatory and fibrotic manifestations. Of note, the expression of Fra-2 was also increased in the myocardium of SSc patients. Conclusions. We demonstrate that all typical manifestations of SSc-related cardiomyopathy are mimicked by Fra-2 tg mice. Moreover, the overexpression of Fra-2 in the myocardium of SSc patients may suggest similar underlying pathomechanisms. Thus, Fra-2 tg mice might be a suitable preclinical model to study the mechanisms and therapeutic approaches of myocardial involvement in SSc. \\ © 2014 American College of Rheumatology. PMID:25371068

Venalis, Paulius; Kumánovics, Gábor; Schulze-Koops, Hendrik; Distler, Alfiya; Dees, Clara; Zerr, Pawel; Palumbo-Zerr, Katrin; Czirják, László; Mackevic, Zygmunt; Lundberg, Ingrid E; Distler, Oliver; Schett, Georg; Distler, Jörg H W

2014-11-01

402

Laser therapy in cardiovascular disease  

NASA Astrophysics Data System (ADS)

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.

Rindge, David

2009-02-01

403

Cost effectiveness of strategies to combat cardiovascular disease, diabetes, and tobacco use in sub-Saharan Africa and South East Asia: mathematical modelling study  

PubMed Central

Objective To determine the relative costs and health effects of interventions to combat cardiovascular disease, diabetes, and tobacco related disease in order to guide the allocation of resources in developing countries. Design Cost effectiveness analysis of 123 single or combined prevention and treatment strategies for cardiovascular disease, diabetes, and smoking by means of a lifetime population model. Setting Two World Health Organization sub-regions of the world: countries in sub-Saharan Africa with very high adult and high child mortality (AfrE) and countries in South East Asia with high adult and high child mortality (SearD). Data sources Demographic and epidemiological data were taken from the WHO databases of mortality and global burden of disease. Estimates of intervention coverage, effectiveness, and resource needs were drawn from clinical trials, observational studies, and treatment guidelines. Unit costs were taken from the WHO-CHOICE (Choosing Interventions that are Cost-Effective) price database. Main outcome measures Cost per disability adjusted life year (DALY) averted, expressed in international dollars ($Int) for the year 2005. Results Most of the interventions studied were considered highly cost effective, meaning they generate one healthy year of life at a cost of <$Int2000 (which is the gross domestic product per capita of the two regions considered here). Interventions that offer particularly good monetary value, and which could be considered for prioritised implementation or scale up, include demand reduction strategies of the Framework Convention for Tobacco Control (<$Int950 and <$Int200 per DALY averted in AfrE and SearD respectively); combination drug therapy for people with a >25% chance of experiencing a cardiovascular event over the next decade, either alone or together with specific multidrug regimens for the secondary prevention of post-acute ischaemic heart disease and stroke (<$Int150 and <$Int230 per DALY averted in AfrE and SearD respectively); and retinopathy screening and glycaemic control for patients with diabetes (<$Int2100 and <$Int950 per DALY averted in AfrE and SearD respectively). Conclusion This comparative economic assessment has identified a set of population-wide and individual strategies for prevention and control of cardiovascular disease that are inexpensive and cost effective in low resource settings. PMID:22389337

2012-01-01

404

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

PubMed

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.Hypertension Research advance online publication, 16 October 2014; doi:10.1038/hr.2014.151. PMID:25319599

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

2014-10-16

405

Bile Acids Regulate Cardiovascular Function  

PubMed Central

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

Khurana, Sandeep; Raufman, Jean-Pierre; Pallone, Thomas L.

2011-01-01

406

Cardiovascular physiology and diseases of amphibians.  

PubMed

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

Heinz-Taheny, Kathleen M

2009-01-01

407

Cardiovascular Diseases (and Oral Health)  

MedlinePLUS

Cardiovascular Diseases Periodontal Disease and Cardiovascular Conditions Heart Disease and Dental Treatment Myocardial Infarction (Heart Attack) High Blood ... it is a current list. Periodontal Disease and Cardiovascular Conditions Periodontal disease can affect your overall health. Over time, it ...

408

Sponsored by: Bluhm Cardiovascular Institute  

E-print Network

Prentice Women's Hospital, Chicago IL The Bluhm Cardiovascular Institute's Center for Vascular Disease and limitations of imaging techniques in various cardiovascular diseases. #12;TARGET AUDIENCE This continuingSponsored by: Bluhm Cardiovascular Institute of Northwestern Memorial Hospital Northwestern

409

Geochemistry and Cardiovascular Diseases  

Microsoft Academic Search

Deficiencies or excesses in the content or availability of trace elements in rocks and soils, or in water flowing through them, is hypothesized as a possible cause of certain chronic diseases, including cardiovascular diseases. Geographic distribution of cardiovascular diseases is often associated with geochemical differences. This trend is particularly evident in the United States and in Europe, with higher rates

R. Masironi; J. R. Todd; P. Elwood; D. B. R. Poole

1979-01-01

410

Androgens and Cardiovascular Disease  

Microsoft Academic Search

Globally, cardiovascular disease will continue causing most human deaths for the foreseeable future. The consistent gen- der gap in life span of approximately 5.6 yr in all advanced economies must derive from gender differences in age- specific cardiovascular death rates, which rise steeply in par- allel for both genders but 5-10 yr earlier in men. The lack of inflection point

PETER Y. LIU; ALISON K. DEATH; DAVID J. HANDELSMAN

2003-01-01

411

Relationship between pain sensitivity, cardiovascular reactivity to cold pressor test and indexes of activity of the adrenergic and opioid system.  

PubMed

An association between increased blood pressure levels and hypoalgesia has been reported in the experimental animal and in man. The relation between pain perception and cardiovascular function is however still obscure. In order to gain some insight into this aspect, normotensive subjects with low and high tolerance to pain, as assessed by tooth pulp stimulation, were compared for blood pressure and heart rate during cold pressor test, 24 hr urinary catecholamines, supine and upright PRA and plasma beta-endorphin levels. No significant difference was observed between the two groups for casual blood pressure, heart rate and PRA. Compared to subjects with low tolerance to pain, those with high tolerance to pain were significantly older and had: 1) significantly higher levels of diastolic blood pressure and of beta endorphin levels during cold pressor test; 2) significantly higher beta-endorphin levels after cold pressor test; 3) a significantly higher excretion of noradrenaline (but not of adrenaline and dopamine). PMID:3072126

Rosa, C; Ghione, S; Mezzasalma, L; Pellegrini, M; Basile Fasolo, C; Giaconi, S; Gazzetti, P; Ferdeghini, M

1988-01-01

412

Salt, Arterial Pressure, and Cardiovascular and Renal Damage  

PubMed Central

This brief review deals with some novel developments regarding the possible role of salt in the pathogenesis of cardiovascular and renal disorders. Studies in both humans and experimental animals are discussed. Increased salt intake is usually associated with an increase in arterial pressure although some controversies still exist. Salt sensitivity of arterial pressure (defined as an increase in arterial pressure on dietary salt overload) was demonstrated in many animal species as well as in humans. However, findings in rats, the most often used animal model, also demonstrated that this salt sensitivity was not uniform; some strains are salt sensitive, while other strains are salt resistant. Salt sensitivity of arterial pressure in humans is also not uniform; less than one-third of normotensive individuals and less than one-half of hypertensive individuals are salt sensitive. Of great importance are findings that excessive salt intake may damage target organs (cardiovascular system and kidneys) irrespective of arterial pressure. Together with an ever-growing consensus that sodium intake in acculturated societies is high, these findings also emphasize the need for reduction in salt intake. Therefore, the adverse cardiovascular and renal effects of salt continue to be a subject of intense study. Current data indicate that a reduction in salt intake should ameliorate, if not prevent, cardiovascular and renal morbidity and mortality, particularly among individuals with hypertension. PMID:21603444

Susic, Dinko; Fares, Hassan; Frohlich, Edward D.

2009-01-01

413

Vitamin D and cardiovascular disease.  

PubMed

It has long been known from case series that vitamin D excess can lead to atherosclerosis and vascular calcification in humans. In the 1980s, ecological studies provided data that deficient human vitamin D status may also increase the risk of developing cardiovascular disease (CVD). The assumption of a biphasic vitamin D effect on CVD is supported by experimental studies: Numerous studies have demonstrated positive effects of the vitamin D hormone (1,25-dihydroxyviramin D) on the cardiovascular system. However, the effects and mechanisms that lead to vascular calcification by vitamin D excess could also be confirmed. Large prospective observational studies support the hypothesis of a U-shaped association between vitamin D and CVD. These studies indicate that deficient circulating 25-hydroxyvitamin D levels (<30 nmol/l) are independently-associated with increased CVD morbidity and mortality. They also suggest that those circulating 25-hydroxyvitamin D levels, which have long been considered to be safe (100-150 nmol/l), are associated with an increased CVD risk. Meanwhile, numerous randomized controlled trials have investigated the effects of vitamin D supplements or ultraviolet B radiation on biochemical cardiovascular risk markers, cardiovascular physiology, and cardiovascular outcomes. Overall, results are mixed with the majority of studies reporting neither beneficial nor adverse vitamin D effects. Several limitations in the study design, which may have prevented beneficial vitamin D effects, are discussed. In conclusion, it must be stated that the role of vitamin D in the prevention and management of CVD as well as the dose-response relationship of potentially harmful effects still remain to be established. PMID:25202039

Zittermann, Armin

2014-09-01

414

DIAGNOSIS NUMBER OF CASES CARDIOVASCULAR  

E-print Network

DIAGNOSIS NUMBER OF CASES CARDIOVASCULAR Cardiovascular disease .........................................................36 Crop Disorder.....................................................12 Digestive